diff --git a/Documentation/admin-guide/tainted-kernels.rst b/Documentation/admin-guide/tainted-kernels.rst
index 700aa72..a0cc017 100644
--- a/Documentation/admin-guide/tainted-kernels.rst
+++ b/Documentation/admin-guide/tainted-kernels.rst
@@ -101,6 +101,7 @@ Bit  Log  Number  Reason that got the kernel tainted
  16  _/X   65536  auxiliary taint, defined for and used by distros
  17  _/T  131072  kernel was built with the struct randomization plugin
  18  _/N  262144  an in-kernel test has been run
+ 19  _/J  524288  userspace used a mutating debug operation in fwctl
 ===  ===  ======  ========================================================
 
 Note: The character ``_`` is representing a blank in this table to make reading
@@ -184,3 +185,7 @@ More detailed explanation for tainting
      build time.
 
  18) ``N`` if an in-kernel test, such as a KUnit test, has been run.
+
+ 19) ``J`` if userpace opened /dev/fwctl/* and performed a FWTCL_RPC_DEBUG_WRITE
+     to use the devices debugging features. Device debugging features could
+     cause the device to malfunction in undefined ways.
diff --git a/Documentation/userspace-api/fwctl/fwctl-cxl.rst b/Documentation/userspace-api/fwctl/fwctl-cxl.rst
new file mode 100644
index 0000000..670b43b
--- /dev/null
+++ b/Documentation/userspace-api/fwctl/fwctl-cxl.rst
@@ -0,0 +1,142 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+================
+fwctl cxl driver
+================
+
+:Author: Dave Jiang
+
+Overview
+========
+
+The CXL spec defines a set of commands that can be issued to the mailbox of a
+CXL device or switch. It also left room for vendor specific commands to be
+issued to the mailbox as well. fwctl provides a path to issue a set of allowed
+mailbox commands from user space to the device moderated by the kernel driver.
+
+The following 3 commands will be used to support CXL Features:
+CXL spec r3.1 8.2.9.6.1 Get Supported Features (Opcode 0500h)
+CXL spec r3.1 8.2.9.6.2 Get Feature (Opcode 0501h)
+CXL spec r3.1 8.2.9.6.3 Set Feature (Opcode 0502h)
+
+The "Get Supported Features" return data may be filtered by the kernel driver to
+drop any features that are forbidden by the kernel or being exclusively used by
+the kernel. The driver will set the "Set Feature Size" of the "Get Supported
+Features Supported Feature Entry" to 0 to indicate that the Feature cannot be
+modified. The "Get Supported Features" command and the "Get Features" falls
+under the fwctl policy of FWCTL_RPC_CONFIGURATION.
+
+For "Set Feature" command, the access policy currently is broken down into two
+categories depending on the Set Feature effects reported by the device. If the
+Set Feature will cause immediate change to the device, the fwctl access policy
+must be FWCTL_RPC_DEBUG_WRITE_FULL. The effects for this level are
+"immediate config change", "immediate data change", "immediate policy change",
+or "immediate log change" for the set effects mask. If the effects are "config
+change with cold reset" or "config change with conventional reset", then the
+fwctl access policy must be FWCTL_RPC_DEBUG_WRITE or higher.
+
+fwctl cxl User API
+==================
+
+.. kernel-doc:: include/uapi/fwctl/cxl.h
+
+1. Driver info query
+--------------------
+
+First step for the app is to issue the ioctl(FWCTL_CMD_INFO). Successful
+invocation of the ioctl implies the Features capability is operational and
+returns an all zeros 32bit payload. A ``struct fwctl_info`` needs to be filled
+out with the ``fwctl_info.out_device_type`` set to ``FWCTL_DEVICE_TYPE_CXL``.
+The return data should be ``struct fwctl_info_cxl`` that contains a reserved
+32bit field that should be all zeros.
+
+2. Send hardware commands
+-------------------------
+
+Next step is to send the 'Get Supported Features' command to the driver from
+user space via ioctl(FWCTL_RPC). A ``struct fwctl_rpc_cxl`` is pointed to
+by ``fwctl_rpc.in``. ``struct fwctl_rpc_cxl.in_payload`` points to
+the hardware input structure that is defined by the CXL spec. ``fwctl_rpc.out``
+points to the buffer that contains a ``struct fwctl_rpc_cxl_out`` that includes
+the hardware output data inlined as ``fwctl_rpc_cxl_out.payload``. This command
+is called twice. First time to retrieve the number of features supported.
+A second time to retrieve the specific feature details as the output data.
+
+After getting the specific feature details, a Get/Set Feature command can be
+appropriately programmed and sent. For a "Set Feature" command, the retrieved
+feature info contains an effects field that details the resulting
+"Set Feature" command will trigger. That will inform the user whether
+the system is configured to allowed the "Set Feature" command or not.
+
+Code example of a Get Feature
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
+        static int cxl_fwctl_rpc_get_test_feature(int fd, struct test_feature *feat_ctx,
+                                                  const uint32_t expected_data)
+        {
+                struct cxl_mbox_get_feat_in *feat_in;
+                struct fwctl_rpc_cxl_out *out;
+                struct fwctl_rpc rpc = {0};
+                struct fwctl_rpc_cxl *in;
+                size_t out_size, in_size;
+                uint32_t val;
+                void *data;
+                int rc;
+
+                in_size = sizeof(*in) + sizeof(*feat_in);
+                rc = posix_memalign((void **)&in, 16, in_size);
+                if (rc)
+                        return -ENOMEM;
+                memset(in, 0, in_size);
+                feat_in = &in->get_feat_in;
+
+                uuid_copy(feat_in->uuid, feat_ctx->uuid);
+                feat_in->count = feat_ctx->get_size;
+
+                out_size = sizeof(*out) + feat_ctx->get_size;
+                rc = posix_memalign((void **)&out, 16, out_size);
+                if (rc)
+                        goto free_in;
+                memset(out, 0, out_size);
+
+                in->opcode = CXL_MBOX_OPCODE_GET_FEATURE;
+                in->op_size = sizeof(*feat_in);
+
+                rpc.size = sizeof(rpc);
+                rpc.scope = FWCTL_RPC_CONFIGURATION;
+                rpc.in_len = in_size;
+                rpc.out_len = out_size;
+                rpc.in = (uint64_t)(uint64_t *)in;
+                rpc.out = (uint64_t)(uint64_t *)out;
+
+                rc = send_command(fd, &rpc, out);
+                if (rc)
+                        goto free_all;
+
+                data = out->payload;
+                val = le32toh(*(__le32 *)data);
+                if (memcmp(&val, &expected_data, sizeof(val)) != 0) {
+                        rc = -ENXIO;
+                        goto free_all;
+                }
+
+        free_all:
+                free(out);
+        free_in:
+                free(in);
+                return rc;
+        }
+
+Take a look at CXL CLI test directory
+<https://github.com/pmem/ndctl/tree/main/test/fwctl.c> for a detailed user code
+for examples on how to exercise this path.
+
+
+fwctl cxl Kernel API
+====================
+
+.. kernel-doc:: drivers/cxl/core/features.c
+   :export:
+.. kernel-doc:: include/cxl/features.h
diff --git a/Documentation/userspace-api/fwctl/fwctl.rst b/Documentation/userspace-api/fwctl/fwctl.rst
new file mode 100644
index 0000000..fdcfe41
--- /dev/null
+++ b/Documentation/userspace-api/fwctl/fwctl.rst
@@ -0,0 +1,286 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===============
+fwctl subsystem
+===============
+
+:Author: Jason Gunthorpe
+
+Overview
+========
+
+Modern devices contain extensive amounts of FW, and in many cases, are largely
+software-defined pieces of hardware. The evolution of this approach is largely a
+reaction to Moore's Law where a chip tape out is now highly expensive, and the
+chip design is extremely large. Replacing fixed HW logic with a flexible and
+tightly coupled FW/HW combination is an effective risk mitigation against chip
+respin. Problems in the HW design can be counteracted in device FW. This is
+especially true for devices which present a stable and backwards compatible
+interface to the operating system driver (such as NVMe).
+
+The FW layer in devices has grown to incredible size and devices frequently
+integrate clusters of fast processors to run it. For example, mlx5 devices have
+over 30MB of FW code, and big configurations operate with over 1GB of FW managed
+runtime state.
+
+The availability of such a flexible layer has created quite a variety in the
+industry where single pieces of silicon are now configurable software-defined
+devices and can operate in substantially different ways depending on the need.
+Further, we often see cases where specific sites wish to operate devices in ways
+that are highly specialized and require applications that have been tailored to
+their unique configuration.
+
+Further, devices have become multi-functional and integrated to the point they
+no longer fit neatly into the kernel's division of subsystems. Modern
+multi-functional devices have drivers, such as bnxt/ice/mlx5/pds, that span many
+subsystems while sharing the underlying hardware using the auxiliary device
+system.
+
+All together this creates a challenge for the operating system, where devices
+have an expansive FW environment that needs robust device-specific debugging
+support, and FW-driven functionality that is not well suited to “generic”
+interfaces. fwctl seeks to allow access to the full device functionality from
+user space in the areas of debuggability, management, and first-boot/nth-boot
+provisioning.
+
+fwctl is aimed at the common device design pattern where the OS and FW
+communicate via an RPC message layer constructed with a queue or mailbox scheme.
+In this case the driver will typically have some layer to deliver RPC messages
+and collect RPC responses from device FW. The in-kernel subsystem drivers that
+operate the device for its primary purposes will use these RPCs to build their
+drivers, but devices also usually have a set of ancillary RPCs that don't really
+fit into any specific subsystem. For example, a HW RAID controller is primarily
+operated by the block layer but also comes with a set of RPCs to administer the
+construction of drives within the HW RAID.
+
+In the past when devices were more single function, individual subsystems would
+grow different approaches to solving some of these common problems. For instance
+monitoring device health, manipulating its FLASH, debugging the FW,
+provisioning, all have various unique interfaces across the kernel.
+
+fwctl's purpose is to define a common set of limited rules, described below,
+that allow user space to securely construct and execute RPCs inside device FW.
+The rules serve as an agreement between the operating system and FW on how to
+correctly design the RPC interface. As a uAPI the subsystem provides a thin
+layer of discovery and a generic uAPI to deliver the RPCs and collect the
+response. It supports a system of user space libraries and tools which will
+use this interface to control the device using the device native protocols.
+
+Scope of Action
+---------------
+
+fwctl drivers are strictly restricted to being a way to operate the device FW.
+It is not an avenue to access random kernel internals, or other operating system
+SW states.
+
+fwctl instances must operate on a well-defined device function, and the device
+should have a well-defined security model for what scope within the physical
+device the function is permitted to access. For instance, the most complex PCIe
+device today may broadly have several function-level scopes:
+
+ 1. A privileged function with full access to the on-device global state and
+    configuration
+
+ 2. Multiple hypervisor functions with control over itself and child functions
+    used with VMs
+
+ 3. Multiple VM functions tightly scoped within the VM
+
+The device may create a logical parent/child relationship between these scopes.
+For instance a child VM's FW may be within the scope of the hypervisor FW. It is
+quite common in the VFIO world that the hypervisor environment has a complex
+provisioning/profiling/configuration responsibility for the function VFIO
+assigns to the VM.
+
+Further, within the function, devices often have RPC commands that fall within
+some general scopes of action (see enum fwctl_rpc_scope):
+
+ 1. Access to function & child configuration, FLASH, etc. that becomes live at a
+    function reset. Access to function & child runtime configuration that is
+    transparent or non-disruptive to any driver or VM.
+
+ 2. Read-only access to function debug information that may report on FW objects
+    in the function & child, including FW objects owned by other kernel
+    subsystems.
+
+ 3. Write access to function & child debug information strictly compatible with
+    the principles of kernel lockdown and kernel integrity protection. Triggers
+    a kernel Taint.
+
+ 4. Full debug device access. Triggers a kernel Taint, requires CAP_SYS_RAWIO.
+
+User space will provide a scope label on each RPC and the kernel must enforce the
+above CAPs and taints based on that scope. A combination of kernel and FW can
+enforce that RPCs are placed in the correct scope by user space.
+
+Denied behavior
+---------------
+
+There are many things this interface must not allow user space to do (without a
+Taint or CAP), broadly derived from the principles of kernel lockdown. Some
+examples:
+
+ 1. DMA to/from arbitrary memory, hang the system, compromise FW integrity with
+    untrusted code, or otherwise compromise device or system security and
+    integrity.
+
+ 2. Provide an abnormal “back door” to kernel drivers. No manipulation of kernel
+    objects owned by kernel drivers.
+
+ 3. Directly configure or otherwise control kernel drivers. A subsystem kernel
+    driver can react to the device configuration at function reset/driver load
+    time, but otherwise must not be coupled to fwctl.
+
+ 4. Operate the HW in a way that overlaps with the core purpose of another
+    primary kernel subsystem, such as read/write to LBAs, send/receive of
+    network packets, or operate an accelerator's data plane.
+
+fwctl is not a replacement for device direct access subsystems like uacce or
+VFIO.
+
+Operations exposed through fwctl's non-taining interfaces should be fully
+sharable with other users of the device. For instance exposing a RPC through
+fwctl should never prevent a kernel subsystem from also concurrently using that
+same RPC or hardware unit down the road. In such cases fwctl will be less
+important than proper kernel subsystems that eventually emerge. Mistakes in this
+area resulting in clashes will be resolved in favour of a kernel implementation.
+
+fwctl User API
+==============
+
+.. kernel-doc:: include/uapi/fwctl/fwctl.h
+.. kernel-doc:: include/uapi/fwctl/mlx5.h
+.. kernel-doc:: include/uapi/fwctl/pds.h
+
+sysfs Class
+-----------
+
+fwctl has a sysfs class (/sys/class/fwctl/fwctlNN/) and character devices
+(/dev/fwctl/fwctlNN) with a simple numbered scheme. The character device
+operates the iotcl uAPI described above.
+
+fwctl devices can be related to driver components in other subsystems through
+sysfs::
+
+    $ ls /sys/class/fwctl/fwctl0/device/infiniband/
+    ibp0s10f0
+
+    $ ls /sys/class/infiniband/ibp0s10f0/device/fwctl/
+    fwctl0/
+
+    $ ls /sys/devices/pci0000:00/0000:00:0a.0/fwctl/fwctl0
+    dev  device  power  subsystem  uevent
+
+User space Community
+--------------------
+
+Drawing inspiration from nvme-cli, participating in the kernel side must come
+with a user space in a common TBD git tree, at a minimum to usefully operate the
+kernel driver. Providing such an implementation is a pre-condition to merging a
+kernel driver.
+
+The goal is to build user space community around some of the shared problems
+we all have, and ideally develop some common user space programs with some
+starting themes of:
+
+ - Device in-field debugging
+
+ - HW provisioning
+
+ - VFIO child device profiling before VM boot
+
+ - Confidential Compute topics (attestation, secure provisioning)
+
+that stretch across all subsystems in the kernel. fwupd is a great example of
+how an excellent user space experience can emerge out of kernel-side diversity.
+
+fwctl Kernel API
+================
+
+.. kernel-doc:: drivers/fwctl/main.c
+   :export:
+.. kernel-doc:: include/linux/fwctl.h
+
+fwctl Driver design
+-------------------
+
+In many cases a fwctl driver is going to be part of a larger cross-subsystem
+device possibly using the auxiliary_device mechanism. In that case several
+subsystems are going to be sharing the same device and FW interface layer so the
+device design must already provide for isolation and cooperation between kernel
+subsystems. fwctl should fit into that same model.
+
+Part of the driver should include a description of how its scope restrictions
+and security model work. The driver and FW together must ensure that RPCs
+provided by user space are mapped to the appropriate scope. If the validation is
+done in the driver then the validation can read a 'command effects' report from
+the device, or hardwire the enforcement. If the validation is done in the FW,
+then the driver should pass the fwctl_rpc_scope to the FW along with the command.
+
+The driver and FW must cooperate to ensure that either fwctl cannot allocate
+any FW resources, or any resources it does allocate are freed on FD closure.  A
+driver primarily constructed around FW RPCs may find that its core PCI function
+and RPC layer belongs under fwctl with auxiliary devices connecting to other
+subsystems.
+
+Each device type must be mindful of Linux's philosophy for stable ABI. The FW
+RPC interface does not have to meet a strictly stable ABI, but it does need to
+meet an expectation that userspace tools that are deployed and in significant
+use don't needlessly break. FW upgrade and kernel upgrade should keep widely
+deployed tooling working.
+
+Development and debugging focused RPCs under more permissive scopes can have
+less stabilitiy if the tools using them are only run under exceptional
+circumstances and not for every day use of the device. Debugging tools may even
+require exact version matching as they may require something similar to DWARF
+debug information from the FW binary.
+
+Security Response
+=================
+
+The kernel remains the gatekeeper for this interface. If violations of the
+scopes, security or isolation principles are found, we have options to let
+devices fix them with a FW update, push a kernel patch to parse and block RPC
+commands or push a kernel patch to block entire firmware versions/devices.
+
+While the kernel can always directly parse and restrict RPCs, it is expected
+that the existing kernel pattern of allowing drivers to delegate validation to
+FW to be a useful design.
+
+Existing Similar Examples
+=========================
+
+The approach described in this document is not a new idea. Direct, or near
+direct device access has been offered by the kernel in different areas for
+decades. With more devices wanting to follow this design pattern it is becoming
+clear that it is not entirely well understood and, more importantly, the
+security considerations are not well defined or agreed upon.
+
+Some examples:
+
+ - HW RAID controllers. This includes RPCs to do things like compose drives into
+   a RAID volume, configure RAID parameters, monitor the HW and more.
+
+ - Baseboard managers. RPCs for configuring settings in the device and more
+
+ - NVMe vendor command capsules. nvme-cli provides access to some monitoring
+   functions that different products have defined, but more exist.
+
+ - CXL also has a NVMe-like vendor command system.
+
+ - DRM allows user space drivers to send commands to the device via kernel
+   mediation
+
+ - RDMA allows user space drivers to directly push commands to the device
+   without kernel involvement
+
+ - Various “raw” APIs, raw HID (SDL2), raw USB, NVMe Generic Interface, etc.
+
+The first 4 are examples of areas that fwctl intends to cover. The latter three
+are examples of denied behavior as they fully overlap with the primary purpose
+of a kernel subsystem.
+
+Some key lessons learned from these past efforts are the importance of having a
+common user space project to use as a pre-condition for obtaining a kernel
+driver. Developing good community around useful software in user space is key to
+getting companies to fund participation to enable their products.
diff --git a/Documentation/userspace-api/fwctl/index.rst b/Documentation/userspace-api/fwctl/index.rst
new file mode 100644
index 0000000..316ac45
--- /dev/null
+++ b/Documentation/userspace-api/fwctl/index.rst
@@ -0,0 +1,14 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Firmware Control (FWCTL) Userspace API
+======================================
+
+A framework that define a common set of limited rules that allows user space
+to securely construct and execute RPCs inside device firmware.
+
+.. toctree::
+   :maxdepth: 1
+
+   fwctl
+   fwctl-cxl
+   pds_fwctl
diff --git a/Documentation/userspace-api/fwctl/pds_fwctl.rst b/Documentation/userspace-api/fwctl/pds_fwctl.rst
new file mode 100644
index 0000000..b5a31f8
--- /dev/null
+++ b/Documentation/userspace-api/fwctl/pds_fwctl.rst
@@ -0,0 +1,46 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+================
+fwctl pds driver
+================
+
+:Author: Shannon Nelson
+
+Overview
+========
+
+The PDS Core device makes a fwctl service available through an
+auxiliary_device named pds_core.fwctl.N.  The pds_fwctl driver binds to
+this device and registers itself with the fwctl subsystem.  The resulting
+userspace interface is used by an application that is a part of the
+AMD Pensando software package for the Distributed Service Card (DSC).
+
+The pds_fwctl driver has little knowledge of the firmware's internals.
+It only knows how to send commands through pds_core's message queue to the
+firmware for fwctl requests.  The set of fwctl operations available
+depends on the firmware in the DSC, and the userspace application
+version must match the firmware so that they can talk to each other.
+
+When a connection is created the pds_fwctl driver requests from the
+firmware a list of firmware object endpoints, and for each endpoint the
+driver requests a list of operations for that endpoint.
+
+Each operation description includes a firmware defined command attribute
+that maps to the FWCTL scope levels.  The driver translates those firmware
+values into the FWCTL scope values which can then be used for filtering the
+scoped user requests.
+
+pds_fwctl User API
+==================
+
+Each RPC request includes the target endpoint and the operation id, and in
+and out buffer lengths and pointers.  The driver verifies the existence
+of the requested endpoint and operations, then checks the request scope
+against the required scope of the operation.  The request is then put
+together with the request data and sent through pds_core's message queue
+to the firmware, and the results are returned to the caller.
+
+The RPC endpoints, operations, and buffer contents are defined by the
+particular firmware package in the device, which varies across the
+available product configurations.  The details are available in the
+specific product SDK documentation.
diff --git a/Documentation/userspace-api/index.rst b/Documentation/userspace-api/index.rst
index 9cbe439..b8c73be 100644
--- a/Documentation/userspace-api/index.rst
+++ b/Documentation/userspace-api/index.rst
@@ -46,6 +46,7 @@ Devices and I/O
    accelerators/ocxl
    dma-buf-heaps
    dma-buf-alloc-exchange
+   fwctl/index
    gpio/index
    iommufd
    media/index
diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index 3cf4183..3d1cd7a 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -333,6 +333,7 @@ Code  Seq#    Include File                                           Comments
 0x97  00-7F  fs/ceph/ioctl.h                                         Ceph file system
 0x99  00-0F                                                          537-Addinboard driver
                                                                      <mailto:buk@buks.ipn.de>
+0x9A  00-0F  include/uapi/fwctl/fwctl.h
 0xA0  all    linux/sdp/sdp.h                                         Industrial Device Project
                                                                      <mailto:kenji@bitgate.com>
 0xA1  0      linux/vtpm_proxy.h                                      TPM Emulator Proxy Driver
diff --git a/MAINTAINERS b/MAINTAINERS
index 3347bd1..8506132 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5886,6 +5886,7 @@ M:	Dan Williams <dan.j.williams@intel.com>
 L:	linux-cxl@vger.kernel.org
 S:	Maintained
 F:	Documentation/driver-api/cxl
+F:	Documentation/userspace-api/fwctl/fwctl-cxl.rst
 F:	drivers/cxl/
 F:	include/cxl/
 F:	include/uapi/linux/cxl_mem.h
@@ -9686,6 +9687,31 @@ F:	kernel/futex/*
 F:	tools/perf/bench/futex*
 F:	tools/testing/selftests/futex/
 
+FWCTL SUBSYSTEM
+M:	Dave Jiang <dave.jiang@intel.com>
+M:	Jason Gunthorpe <jgg@nvidia.com>
+M:	Saeed Mahameed <saeedm@nvidia.com>
+R:	Jonathan Cameron <Jonathan.Cameron@huawei.com>
+S:	Maintained
+F:	Documentation/userspace-api/fwctl/
+F:	drivers/fwctl/
+F:	include/linux/fwctl.h
+F:	include/uapi/fwctl/
+
+FWCTL MLX5 DRIVER
+M:	Saeed Mahameed <saeedm@nvidia.com>
+R:	Itay Avraham <itayavr@nvidia.com>
+L:	linux-kernel@vger.kernel.org
+S:	Maintained
+F:	drivers/fwctl/mlx5/
+
+FWCTL PDS DRIVER
+M:	Brett Creeley <brett.creeley@amd.com>
+R:	Shannon Nelson <shannon.nelson@amd.com>
+L:	linux-kernel@vger.kernel.org
+S:	Maintained
+F:	drivers/fwctl/pds/
+
 GALAXYCORE GC0308 CAMERA SENSOR DRIVER
 M:	Sebastian Reichel <sre@kernel.org>
 L:	linux-media@vger.kernel.org
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 7bdad83..7c556c5 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -21,6 +21,8 @@ source "drivers/connector/Kconfig"
 
 source "drivers/firmware/Kconfig"
 
+source "drivers/fwctl/Kconfig"
+
 source "drivers/gnss/Kconfig"
 
 source "drivers/mtd/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 45d1c3e..b5749cf 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -135,6 +135,7 @@ obj-y				+= ufs/
 obj-$(CONFIG_MEMSTICK)		+= memstick/
 obj-$(CONFIG_INFINIBAND)	+= infiniband/
 obj-y				+= firmware/
+obj-$(CONFIG_FWCTL)		+= fwctl/
 obj-$(CONFIG_CRYPTO)		+= crypto/
 obj-$(CONFIG_SUPERH)		+= sh/
 obj-y				+= clocksource/
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
index 876469e..8ac1e9d 100644
--- a/drivers/cxl/Kconfig
+++ b/drivers/cxl/Kconfig
@@ -7,6 +7,7 @@ menuconfig CXL_BUS
 	select PCI_DOE
 	select FIRMWARE_TABLE
 	select NUMA_KEEP_MEMINFO if NUMA_MEMBLKS
+	select FWCTL if CXL_FEATURES
 	help
 	  CXL is a bus that is electrically compatible with PCI Express, but
 	  layers three protocols on that signalling (CXL.io, CXL.cache, and
@@ -102,6 +103,17 @@ config CXL_MEM
 
 	  If unsure say 'm'.
 
+config CXL_FEATURES
+	bool "CXL: Features"
+	depends on CXL_PCI
+	help
+	  Enable support for CXL Features. A CXL device that includes a mailbox
+	  supports commands that allows listing, getting, and setting of
+	  optionally defined features such as memory sparing or post package
+	  sparing. Vendors may define custom features for the device.
+
+	  If unsure say 'n'
+
 config CXL_PORT
 	default CXL_BUS
 	tristate
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index 9259bcc..b0bfbd9 100644
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -16,3 +16,4 @@ cxl_core-y += pmu.o
 cxl_core-y += cdat.o
 cxl_core-$(CONFIG_TRACING) += trace.o
 cxl_core-$(CONFIG_CXL_REGION) += region.o
+cxl_core-$(CONFIG_CXL_FEATURES) += features.o
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 800466f..17e99a2 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -4,6 +4,8 @@
 #ifndef __CXL_CORE_H__
 #define __CXL_CORE_H__
 
+#include <cxl/mailbox.h>
+
 extern const struct device_type cxl_nvdimm_bridge_type;
 extern const struct device_type cxl_nvdimm_type;
 extern const struct device_type cxl_pmu_type;
@@ -65,9 +67,9 @@ static inline void cxl_region_exit(void)
 
 struct cxl_send_command;
 struct cxl_mem_query_commands;
-int cxl_query_cmd(struct cxl_memdev *cxlmd,
+int cxl_query_cmd(struct cxl_mailbox *cxl_mbox,
 		  struct cxl_mem_query_commands __user *q);
-int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s);
+int cxl_send_cmd(struct cxl_mailbox *cxl_mbox, struct cxl_send_command __user *s);
 void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr,
 				   resource_size_t length);
 
@@ -115,4 +117,15 @@ bool cxl_need_node_perf_attrs_update(int nid);
 int cxl_port_get_switch_dport_bandwidth(struct cxl_port *port,
 					struct access_coordinate *c);
 
+#ifdef CONFIG_CXL_FEATURES
+size_t cxl_get_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid,
+		       enum cxl_get_feat_selection selection,
+		       void *feat_out, size_t feat_out_size, u16 offset,
+		       u16 *return_code);
+int cxl_set_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid,
+		    u8 feat_version, const void *feat_data,
+		    size_t feat_data_size, u32 feat_flag, u16 offset,
+		    u16 *return_code);
+#endif
+
 #endif /* __CXL_CORE_H__ */
diff --git a/drivers/cxl/core/features.c b/drivers/cxl/core/features.c
new file mode 100644
index 0000000..f4daefe
--- /dev/null
+++ b/drivers/cxl/core/features.c
@@ -0,0 +1,708 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2024-2025 Intel Corporation. All rights reserved. */
+#include <linux/fwctl.h>
+#include <linux/device.h>
+#include <cxl/mailbox.h>
+#include <cxl/features.h>
+#include <uapi/fwctl/cxl.h>
+#include "cxl.h"
+#include "core.h"
+#include "cxlmem.h"
+
+/* All the features below are exclusive to the kernel */
+static const uuid_t cxl_exclusive_feats[] = {
+	CXL_FEAT_PATROL_SCRUB_UUID,
+	CXL_FEAT_ECS_UUID,
+	CXL_FEAT_SPPR_UUID,
+	CXL_FEAT_HPPR_UUID,
+	CXL_FEAT_CACHELINE_SPARING_UUID,
+	CXL_FEAT_ROW_SPARING_UUID,
+	CXL_FEAT_BANK_SPARING_UUID,
+	CXL_FEAT_RANK_SPARING_UUID,
+};
+
+static bool is_cxl_feature_exclusive_by_uuid(const uuid_t *uuid)
+{
+	for (int i = 0; i < ARRAY_SIZE(cxl_exclusive_feats); i++) {
+		if (uuid_equal(uuid, &cxl_exclusive_feats[i]))
+			return true;
+	}
+
+	return false;
+}
+
+static bool is_cxl_feature_exclusive(struct cxl_feat_entry *entry)
+{
+	return is_cxl_feature_exclusive_by_uuid(&entry->uuid);
+}
+
+inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds)
+{
+	return cxlds->cxlfs;
+}
+EXPORT_SYMBOL_NS_GPL(to_cxlfs, "CXL");
+
+static int cxl_get_supported_features_count(struct cxl_mailbox *cxl_mbox)
+{
+	struct cxl_mbox_get_sup_feats_out mbox_out;
+	struct cxl_mbox_get_sup_feats_in mbox_in;
+	struct cxl_mbox_cmd mbox_cmd;
+	int rc;
+
+	memset(&mbox_in, 0, sizeof(mbox_in));
+	mbox_in.count = cpu_to_le32(sizeof(mbox_out));
+	memset(&mbox_out, 0, sizeof(mbox_out));
+	mbox_cmd = (struct cxl_mbox_cmd) {
+		.opcode = CXL_MBOX_OP_GET_SUPPORTED_FEATURES,
+		.size_in = sizeof(mbox_in),
+		.payload_in = &mbox_in,
+		.size_out = sizeof(mbox_out),
+		.payload_out = &mbox_out,
+		.min_out = sizeof(mbox_out),
+	};
+	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
+	if (rc < 0)
+		return rc;
+
+	return le16_to_cpu(mbox_out.supported_feats);
+}
+
+static struct cxl_feat_entries *
+get_supported_features(struct cxl_features_state *cxlfs)
+{
+	int remain_feats, max_size, max_feats, start, rc, hdr_size;
+	struct cxl_mailbox *cxl_mbox = &cxlfs->cxlds->cxl_mbox;
+	int feat_size = sizeof(struct cxl_feat_entry);
+	struct cxl_mbox_get_sup_feats_in mbox_in;
+	struct cxl_feat_entry *entry;
+	struct cxl_mbox_cmd mbox_cmd;
+	int user_feats = 0;
+	int count;
+
+	count = cxl_get_supported_features_count(cxl_mbox);
+	if (count <= 0)
+		return NULL;
+
+	struct cxl_feat_entries *entries __free(kvfree) =
+		kvmalloc(struct_size(entries, ent, count), GFP_KERNEL);
+	if (!entries)
+		return NULL;
+
+	struct cxl_mbox_get_sup_feats_out *mbox_out __free(kvfree) =
+		kvmalloc(cxl_mbox->payload_size, GFP_KERNEL);
+	if (!mbox_out)
+		return NULL;
+
+	hdr_size = struct_size(mbox_out, ents, 0);
+	max_size = cxl_mbox->payload_size - hdr_size;
+	/* max feat entries that can fit in mailbox max payload size */
+	max_feats = max_size / feat_size;
+	entry = entries->ent;
+
+	start = 0;
+	remain_feats = count;
+	do {
+		int retrieved, alloc_size, copy_feats;
+		int num_entries;
+
+		if (remain_feats > max_feats) {
+			alloc_size = struct_size(mbox_out, ents, max_feats);
+			remain_feats = remain_feats - max_feats;
+			copy_feats = max_feats;
+		} else {
+			alloc_size = struct_size(mbox_out, ents, remain_feats);
+			copy_feats = remain_feats;
+			remain_feats = 0;
+		}
+
+		memset(&mbox_in, 0, sizeof(mbox_in));
+		mbox_in.count = cpu_to_le32(alloc_size);
+		mbox_in.start_idx = cpu_to_le16(start);
+		memset(mbox_out, 0, alloc_size);
+		mbox_cmd = (struct cxl_mbox_cmd) {
+			.opcode = CXL_MBOX_OP_GET_SUPPORTED_FEATURES,
+			.size_in = sizeof(mbox_in),
+			.payload_in = &mbox_in,
+			.size_out = alloc_size,
+			.payload_out = mbox_out,
+			.min_out = hdr_size,
+		};
+		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
+		if (rc < 0)
+			return NULL;
+
+		if (mbox_cmd.size_out <= hdr_size)
+			return NULL;
+
+		/*
+		 * Make sure retrieved out buffer is multiple of feature
+		 * entries.
+		 */
+		retrieved = mbox_cmd.size_out - hdr_size;
+		if (retrieved % feat_size)
+			return NULL;
+
+		num_entries = le16_to_cpu(mbox_out->num_entries);
+		/*
+		 * If the reported output entries * defined entry size !=
+		 * retrieved output bytes, then the output package is incorrect.
+		 */
+		if (num_entries * feat_size != retrieved)
+			return NULL;
+
+		memcpy(entry, mbox_out->ents, retrieved);
+		for (int i = 0; i < num_entries; i++) {
+			if (!is_cxl_feature_exclusive(entry + i))
+				user_feats++;
+		}
+		entry += num_entries;
+		/*
+		 * If the number of output entries is less than expected, add the
+		 * remaining entries to the next batch.
+		 */
+		remain_feats += copy_feats - num_entries;
+		start += num_entries;
+	} while (remain_feats);
+
+	entries->num_features = count;
+	entries->num_user_features = user_feats;
+
+	return no_free_ptr(entries);
+}
+
+static void free_cxlfs(void *_cxlfs)
+{
+	struct cxl_features_state *cxlfs = _cxlfs;
+	struct cxl_dev_state *cxlds = cxlfs->cxlds;
+
+	cxlds->cxlfs = NULL;
+	kvfree(cxlfs->entries);
+	kfree(cxlfs);
+}
+
+/**
+ * devm_cxl_setup_features() - Allocate and initialize features context
+ * @cxlds: CXL device context
+ *
+ * Return 0 on success or -errno on failure.
+ */
+int devm_cxl_setup_features(struct cxl_dev_state *cxlds)
+{
+	struct cxl_mailbox *cxl_mbox = &cxlds->cxl_mbox;
+
+	if (cxl_mbox->feat_cap < CXL_FEATURES_RO)
+		return -ENODEV;
+
+	struct cxl_features_state *cxlfs __free(kfree) =
+		kzalloc(sizeof(*cxlfs), GFP_KERNEL);
+	if (!cxlfs)
+		return -ENOMEM;
+
+	cxlfs->cxlds = cxlds;
+
+	cxlfs->entries = get_supported_features(cxlfs);
+	if (!cxlfs->entries)
+		return -ENOMEM;
+
+	cxlds->cxlfs = cxlfs;
+
+	return devm_add_action_or_reset(cxlds->dev, free_cxlfs, no_free_ptr(cxlfs));
+}
+EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_features, "CXL");
+
+size_t cxl_get_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid,
+		       enum cxl_get_feat_selection selection,
+		       void *feat_out, size_t feat_out_size, u16 offset,
+		       u16 *return_code)
+{
+	size_t data_to_rd_size, size_out;
+	struct cxl_mbox_get_feat_in pi;
+	struct cxl_mbox_cmd mbox_cmd;
+	size_t data_rcvd_size = 0;
+	int rc;
+
+	if (return_code)
+		*return_code = CXL_MBOX_CMD_RC_INPUT;
+
+	if (!feat_out || !feat_out_size)
+		return 0;
+
+	size_out = min(feat_out_size, cxl_mbox->payload_size);
+	uuid_copy(&pi.uuid, feat_uuid);
+	pi.selection = selection;
+	do {
+		data_to_rd_size = min(feat_out_size - data_rcvd_size,
+				      cxl_mbox->payload_size);
+		pi.offset = cpu_to_le16(offset + data_rcvd_size);
+		pi.count = cpu_to_le16(data_to_rd_size);
+
+		mbox_cmd = (struct cxl_mbox_cmd) {
+			.opcode = CXL_MBOX_OP_GET_FEATURE,
+			.size_in = sizeof(pi),
+			.payload_in = &pi,
+			.size_out = size_out,
+			.payload_out = feat_out + data_rcvd_size,
+			.min_out = data_to_rd_size,
+		};
+		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
+		if (rc < 0 || !mbox_cmd.size_out) {
+			if (return_code)
+				*return_code = mbox_cmd.return_code;
+			return 0;
+		}
+		data_rcvd_size += mbox_cmd.size_out;
+	} while (data_rcvd_size < feat_out_size);
+
+	if (return_code)
+		*return_code = CXL_MBOX_CMD_RC_SUCCESS;
+
+	return data_rcvd_size;
+}
+
+/*
+ * FEAT_DATA_MIN_PAYLOAD_SIZE - min extra number of bytes should be
+ * available in the mailbox for storing the actual feature data so that
+ * the feature data transfer would work as expected.
+ */
+#define FEAT_DATA_MIN_PAYLOAD_SIZE 10
+int cxl_set_feature(struct cxl_mailbox *cxl_mbox,
+		    const uuid_t *feat_uuid, u8 feat_version,
+		    const void *feat_data, size_t feat_data_size,
+		    u32 feat_flag, u16 offset, u16 *return_code)
+{
+	size_t data_in_size, data_sent_size = 0;
+	struct cxl_mbox_cmd mbox_cmd;
+	size_t hdr_size;
+
+	if (return_code)
+		*return_code = CXL_MBOX_CMD_RC_INPUT;
+
+	struct cxl_mbox_set_feat_in *pi __free(kfree) =
+			kzalloc(cxl_mbox->payload_size, GFP_KERNEL);
+	if (!pi)
+		return -ENOMEM;
+
+	uuid_copy(&pi->uuid, feat_uuid);
+	pi->version = feat_version;
+	feat_flag &= ~CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK;
+	feat_flag |= CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET;
+	hdr_size = sizeof(pi->hdr);
+	/*
+	 * Check minimum mbox payload size is available for
+	 * the feature data transfer.
+	 */
+	if (hdr_size + FEAT_DATA_MIN_PAYLOAD_SIZE > cxl_mbox->payload_size)
+		return -ENOMEM;
+
+	if (hdr_size + feat_data_size <= cxl_mbox->payload_size) {
+		pi->flags = cpu_to_le32(feat_flag |
+					CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER);
+		data_in_size = feat_data_size;
+	} else {
+		pi->flags = cpu_to_le32(feat_flag |
+					CXL_SET_FEAT_FLAG_INITIATE_DATA_TRANSFER);
+		data_in_size = cxl_mbox->payload_size - hdr_size;
+	}
+
+	do {
+		int rc;
+
+		pi->offset = cpu_to_le16(offset + data_sent_size);
+		memcpy(pi->feat_data, feat_data + data_sent_size, data_in_size);
+		mbox_cmd = (struct cxl_mbox_cmd) {
+			.opcode = CXL_MBOX_OP_SET_FEATURE,
+			.size_in = hdr_size + data_in_size,
+			.payload_in = pi,
+		};
+		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
+		if (rc < 0) {
+			if (return_code)
+				*return_code = mbox_cmd.return_code;
+			return rc;
+		}
+
+		data_sent_size += data_in_size;
+		if (data_sent_size >= feat_data_size) {
+			if (return_code)
+				*return_code = CXL_MBOX_CMD_RC_SUCCESS;
+			return 0;
+		}
+
+		if ((feat_data_size - data_sent_size) <= (cxl_mbox->payload_size - hdr_size)) {
+			data_in_size = feat_data_size - data_sent_size;
+			pi->flags = cpu_to_le32(feat_flag |
+						CXL_SET_FEAT_FLAG_FINISH_DATA_TRANSFER);
+		} else {
+			pi->flags = cpu_to_le32(feat_flag |
+						CXL_SET_FEAT_FLAG_CONTINUE_DATA_TRANSFER);
+		}
+	} while (true);
+}
+
+/* FWCTL support */
+
+static inline struct cxl_memdev *fwctl_to_memdev(struct fwctl_device *fwctl_dev)
+{
+	return to_cxl_memdev(fwctl_dev->dev.parent);
+}
+
+static int cxlctl_open_uctx(struct fwctl_uctx *uctx)
+{
+	return 0;
+}
+
+static void cxlctl_close_uctx(struct fwctl_uctx *uctx)
+{
+}
+
+static struct cxl_feat_entry *
+get_support_feature_info(struct cxl_features_state *cxlfs,
+			 const struct fwctl_rpc_cxl *rpc_in)
+{
+	struct cxl_feat_entry *feat;
+	const uuid_t *uuid;
+
+	if (rpc_in->op_size < sizeof(uuid))
+		return ERR_PTR(-EINVAL);
+
+	uuid = &rpc_in->set_feat_in.uuid;
+
+	for (int i = 0; i < cxlfs->entries->num_features; i++) {
+		feat = &cxlfs->entries->ent[i];
+		if (uuid_equal(uuid, &feat->uuid))
+			return feat;
+	}
+
+	return ERR_PTR(-EINVAL);
+}
+
+static void *cxlctl_get_supported_features(struct cxl_features_state *cxlfs,
+					   const struct fwctl_rpc_cxl *rpc_in,
+					   size_t *out_len)
+{
+	const struct cxl_mbox_get_sup_feats_in *feat_in;
+	struct cxl_mbox_get_sup_feats_out *feat_out;
+	struct cxl_feat_entry *pos;
+	size_t out_size;
+	int requested;
+	u32 count;
+	u16 start;
+	int i;
+
+	if (rpc_in->op_size != sizeof(*feat_in))
+		return ERR_PTR(-EINVAL);
+
+	feat_in = &rpc_in->get_sup_feats_in;
+	count = le32_to_cpu(feat_in->count);
+	start = le16_to_cpu(feat_in->start_idx);
+	requested = count / sizeof(*pos);
+
+	/*
+	 * Make sure that the total requested number of entries is not greater
+	 * than the total number of supported features allowed for userspace.
+	 */
+	if (start >= cxlfs->entries->num_features)
+		return ERR_PTR(-EINVAL);
+
+	requested = min_t(int, requested, cxlfs->entries->num_features - start);
+
+	out_size = sizeof(struct fwctl_rpc_cxl_out) +
+		struct_size(feat_out, ents, requested);
+
+	struct fwctl_rpc_cxl_out *rpc_out __free(kvfree) =
+		kvzalloc(out_size, GFP_KERNEL);
+	if (!rpc_out)
+		return ERR_PTR(-ENOMEM);
+
+	rpc_out->size = struct_size(feat_out, ents, requested);
+	feat_out = &rpc_out->get_sup_feats_out;
+	if (requested == 0) {
+		feat_out->num_entries = cpu_to_le16(requested);
+		feat_out->supported_feats =
+			cpu_to_le16(cxlfs->entries->num_features);
+		rpc_out->retval = CXL_MBOX_CMD_RC_SUCCESS;
+		*out_len = out_size;
+		return no_free_ptr(rpc_out);
+	}
+
+	for (i = start, pos = &feat_out->ents[0];
+	     i < cxlfs->entries->num_features; i++, pos++) {
+		if (i - start == requested)
+			break;
+
+		memcpy(pos, &cxlfs->entries->ent[i], sizeof(*pos));
+		/*
+		 * If the feature is exclusive, set the set_feat_size to 0 to
+		 * indicate that the feature is not changeable.
+		 */
+		if (is_cxl_feature_exclusive(pos)) {
+			u32 flags;
+
+			pos->set_feat_size = 0;
+			flags = le32_to_cpu(pos->flags);
+			flags &= ~CXL_FEATURE_F_CHANGEABLE;
+			pos->flags = cpu_to_le32(flags);
+		}
+	}
+
+	feat_out->num_entries = cpu_to_le16(requested);
+	feat_out->supported_feats = cpu_to_le16(cxlfs->entries->num_features);
+	rpc_out->retval = CXL_MBOX_CMD_RC_SUCCESS;
+	*out_len = out_size;
+
+	return no_free_ptr(rpc_out);
+}
+
+static void *cxlctl_get_feature(struct cxl_features_state *cxlfs,
+				const struct fwctl_rpc_cxl *rpc_in,
+				size_t *out_len)
+{
+	struct cxl_mailbox *cxl_mbox = &cxlfs->cxlds->cxl_mbox;
+	const struct cxl_mbox_get_feat_in *feat_in;
+	u16 offset, count, return_code;
+	size_t out_size = *out_len;
+
+	if (rpc_in->op_size != sizeof(*feat_in))
+		return ERR_PTR(-EINVAL);
+
+	feat_in = &rpc_in->get_feat_in;
+	offset = le16_to_cpu(feat_in->offset);
+	count = le16_to_cpu(feat_in->count);
+
+	if (!count)
+		return ERR_PTR(-EINVAL);
+
+	struct fwctl_rpc_cxl_out *rpc_out __free(kvfree) =
+		kvzalloc(out_size, GFP_KERNEL);
+	if (!rpc_out)
+		return ERR_PTR(-ENOMEM);
+
+	out_size = cxl_get_feature(cxl_mbox, &feat_in->uuid,
+				   feat_in->selection, rpc_out->payload,
+				   count, offset, &return_code);
+	*out_len = sizeof(struct fwctl_rpc_cxl_out);
+	if (!out_size) {
+		rpc_out->size = 0;
+		rpc_out->retval = return_code;
+		return no_free_ptr(rpc_out);
+	}
+
+	rpc_out->size = out_size;
+	rpc_out->retval = CXL_MBOX_CMD_RC_SUCCESS;
+	*out_len += out_size;
+
+	return no_free_ptr(rpc_out);
+}
+
+static void *cxlctl_set_feature(struct cxl_features_state *cxlfs,
+				const struct fwctl_rpc_cxl *rpc_in,
+				size_t *out_len)
+{
+	struct cxl_mailbox *cxl_mbox = &cxlfs->cxlds->cxl_mbox;
+	const struct cxl_mbox_set_feat_in *feat_in;
+	size_t out_size, data_size;
+	u16 offset, return_code;
+	u32 flags;
+	int rc;
+
+	if (rpc_in->op_size <= sizeof(feat_in->hdr))
+		return ERR_PTR(-EINVAL);
+
+	feat_in = &rpc_in->set_feat_in;
+
+	if (is_cxl_feature_exclusive_by_uuid(&feat_in->uuid))
+		return ERR_PTR(-EPERM);
+
+	offset = le16_to_cpu(feat_in->offset);
+	flags = le32_to_cpu(feat_in->flags);
+	out_size = *out_len;
+
+	struct fwctl_rpc_cxl_out *rpc_out __free(kvfree) =
+		kvzalloc(out_size, GFP_KERNEL);
+	if (!rpc_out)
+		return ERR_PTR(-ENOMEM);
+
+	rpc_out->size = 0;
+
+	data_size = rpc_in->op_size - sizeof(feat_in->hdr);
+	rc = cxl_set_feature(cxl_mbox, &feat_in->uuid,
+			     feat_in->version, feat_in->feat_data,
+			     data_size, flags, offset, &return_code);
+	if (rc) {
+		rpc_out->retval = return_code;
+		return no_free_ptr(rpc_out);
+	}
+
+	rpc_out->retval = CXL_MBOX_CMD_RC_SUCCESS;
+	*out_len = sizeof(*rpc_out);
+
+	return no_free_ptr(rpc_out);
+}
+
+static bool cxlctl_validate_set_features(struct cxl_features_state *cxlfs,
+					 const struct fwctl_rpc_cxl *rpc_in,
+					 enum fwctl_rpc_scope scope)
+{
+	u16 effects, imm_mask, reset_mask;
+	struct cxl_feat_entry *feat;
+	u32 flags;
+
+	feat = get_support_feature_info(cxlfs, rpc_in);
+	if (IS_ERR(feat))
+		return false;
+
+	/* Ensure that the attribute is changeable */
+	flags = le32_to_cpu(feat->flags);
+	if (!(flags & CXL_FEATURE_F_CHANGEABLE))
+		return false;
+
+	effects = le16_to_cpu(feat->effects);
+
+	/*
+	 * Reserved bits are set, rejecting since the effects is not
+	 * comprehended by the driver.
+	 */
+	if (effects & CXL_CMD_EFFECTS_RESERVED) {
+		dev_warn_once(cxlfs->cxlds->dev,
+			      "Reserved bits set in the Feature effects field!\n");
+		return false;
+	}
+
+	/* Currently no user background command support */
+	if (effects & CXL_CMD_BACKGROUND)
+		return false;
+
+	/* Effects cause immediate change, highest security scope is needed */
+	imm_mask = CXL_CMD_CONFIG_CHANGE_IMMEDIATE |
+		   CXL_CMD_DATA_CHANGE_IMMEDIATE |
+		   CXL_CMD_POLICY_CHANGE_IMMEDIATE |
+		   CXL_CMD_LOG_CHANGE_IMMEDIATE;
+
+	reset_mask = CXL_CMD_CONFIG_CHANGE_COLD_RESET |
+		     CXL_CMD_CONFIG_CHANGE_CONV_RESET |
+		     CXL_CMD_CONFIG_CHANGE_CXL_RESET;
+
+	/* If no immediate or reset effect set, The hardware has a bug */
+	if (!(effects & imm_mask) && !(effects & reset_mask))
+		return false;
+
+	/*
+	 * If the Feature setting causes immediate configuration change
+	 * then we need the full write permission policy.
+	 */
+	if (effects & imm_mask && scope >= FWCTL_RPC_DEBUG_WRITE_FULL)
+		return true;
+
+	/*
+	 * If the Feature setting only causes configuration change
+	 * after a reset, then the lesser level of write permission
+	 * policy is ok.
+	 */
+	if (!(effects & imm_mask) && scope >= FWCTL_RPC_DEBUG_WRITE)
+		return true;
+
+	return false;
+}
+
+static bool cxlctl_validate_hw_command(struct cxl_features_state *cxlfs,
+				       const struct fwctl_rpc_cxl *rpc_in,
+				       enum fwctl_rpc_scope scope,
+				       u16 opcode)
+{
+	struct cxl_mailbox *cxl_mbox = &cxlfs->cxlds->cxl_mbox;
+
+	switch (opcode) {
+	case CXL_MBOX_OP_GET_SUPPORTED_FEATURES:
+	case CXL_MBOX_OP_GET_FEATURE:
+		if (cxl_mbox->feat_cap < CXL_FEATURES_RO)
+			return false;
+		if (scope >= FWCTL_RPC_CONFIGURATION)
+			return true;
+		return false;
+	case CXL_MBOX_OP_SET_FEATURE:
+		if (cxl_mbox->feat_cap < CXL_FEATURES_RW)
+			return false;
+		return cxlctl_validate_set_features(cxlfs, rpc_in, scope);
+	default:
+		return false;
+	}
+}
+
+static void *cxlctl_handle_commands(struct cxl_features_state *cxlfs,
+				    const struct fwctl_rpc_cxl *rpc_in,
+				    size_t *out_len, u16 opcode)
+{
+	switch (opcode) {
+	case CXL_MBOX_OP_GET_SUPPORTED_FEATURES:
+		return cxlctl_get_supported_features(cxlfs, rpc_in, out_len);
+	case CXL_MBOX_OP_GET_FEATURE:
+		return cxlctl_get_feature(cxlfs, rpc_in, out_len);
+	case CXL_MBOX_OP_SET_FEATURE:
+		return cxlctl_set_feature(cxlfs, rpc_in, out_len);
+	default:
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+}
+
+static void *cxlctl_fw_rpc(struct fwctl_uctx *uctx, enum fwctl_rpc_scope scope,
+			   void *in, size_t in_len, size_t *out_len)
+{
+	struct fwctl_device *fwctl_dev = uctx->fwctl;
+	struct cxl_memdev *cxlmd = fwctl_to_memdev(fwctl_dev);
+	struct cxl_features_state *cxlfs = to_cxlfs(cxlmd->cxlds);
+	const struct fwctl_rpc_cxl *rpc_in = in;
+	u16 opcode = rpc_in->opcode;
+
+	if (!cxlctl_validate_hw_command(cxlfs, rpc_in, scope, opcode))
+		return ERR_PTR(-EINVAL);
+
+	return cxlctl_handle_commands(cxlfs, rpc_in, out_len, opcode);
+}
+
+static const struct fwctl_ops cxlctl_ops = {
+	.device_type = FWCTL_DEVICE_TYPE_CXL,
+	.uctx_size = sizeof(struct fwctl_uctx),
+	.open_uctx = cxlctl_open_uctx,
+	.close_uctx = cxlctl_close_uctx,
+	.fw_rpc = cxlctl_fw_rpc,
+};
+
+DEFINE_FREE(free_fwctl_dev, struct fwctl_device *, if (_T) fwctl_put(_T))
+
+static void free_memdev_fwctl(void *_fwctl_dev)
+{
+	struct fwctl_device *fwctl_dev = _fwctl_dev;
+
+	fwctl_unregister(fwctl_dev);
+	fwctl_put(fwctl_dev);
+}
+
+int devm_cxl_setup_fwctl(struct cxl_memdev *cxlmd)
+{
+	struct cxl_dev_state *cxlds = cxlmd->cxlds;
+	struct cxl_features_state *cxlfs;
+	int rc;
+
+	cxlfs = to_cxlfs(cxlds);
+	if (!cxlfs)
+		return -ENODEV;
+
+	/* No need to setup FWCTL if there are no user allowed features found */
+	if (!cxlfs->entries->num_user_features)
+		return -ENODEV;
+
+	struct fwctl_device *fwctl_dev __free(free_fwctl_dev) =
+		_fwctl_alloc_device(&cxlmd->dev, &cxlctl_ops, sizeof(*fwctl_dev));
+	if (!fwctl_dev)
+		return -ENOMEM;
+
+	rc = fwctl_register(fwctl_dev);
+	if (rc)
+		return rc;
+
+	return devm_add_action_or_reset(&cxlmd->dev, free_memdev_fwctl,
+					no_free_ptr(fwctl_dev));
+}
+EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_fwctl, "CXL");
+
+MODULE_IMPORT_NS("FWCTL");
diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 548564c..78c5346 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -349,40 +349,39 @@ static bool cxl_payload_from_user_allowed(u16 opcode, void *payload_in)
 	return true;
 }
 
-static int cxl_mbox_cmd_ctor(struct cxl_mbox_cmd *mbox,
-			     struct cxl_memdev_state *mds, u16 opcode,
+static int cxl_mbox_cmd_ctor(struct cxl_mbox_cmd *mbox_cmd,
+			     struct cxl_mailbox *cxl_mbox, u16 opcode,
 			     size_t in_size, size_t out_size, u64 in_payload)
 {
-	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
-	*mbox = (struct cxl_mbox_cmd) {
+	*mbox_cmd = (struct cxl_mbox_cmd) {
 		.opcode = opcode,
 		.size_in = in_size,
 	};
 
 	if (in_size) {
-		mbox->payload_in = vmemdup_user(u64_to_user_ptr(in_payload),
-						in_size);
-		if (IS_ERR(mbox->payload_in))
-			return PTR_ERR(mbox->payload_in);
+		mbox_cmd->payload_in = vmemdup_user(u64_to_user_ptr(in_payload),
+						    in_size);
+		if (IS_ERR(mbox_cmd->payload_in))
+			return PTR_ERR(mbox_cmd->payload_in);
 
-		if (!cxl_payload_from_user_allowed(opcode, mbox->payload_in)) {
-			dev_dbg(mds->cxlds.dev, "%s: input payload not allowed\n",
+		if (!cxl_payload_from_user_allowed(opcode, mbox_cmd->payload_in)) {
+			dev_dbg(cxl_mbox->host, "%s: input payload not allowed\n",
 				cxl_mem_opcode_to_name(opcode));
-			kvfree(mbox->payload_in);
+			kvfree(mbox_cmd->payload_in);
 			return -EBUSY;
 		}
 	}
 
 	/* Prepare to handle a full payload for variable sized output */
 	if (out_size == CXL_VARIABLE_PAYLOAD)
-		mbox->size_out = cxl_mbox->payload_size;
+		mbox_cmd->size_out = cxl_mbox->payload_size;
 	else
-		mbox->size_out = out_size;
+		mbox_cmd->size_out = out_size;
 
-	if (mbox->size_out) {
-		mbox->payload_out = kvzalloc(mbox->size_out, GFP_KERNEL);
-		if (!mbox->payload_out) {
-			kvfree(mbox->payload_in);
+	if (mbox_cmd->size_out) {
+		mbox_cmd->payload_out = kvzalloc(mbox_cmd->size_out, GFP_KERNEL);
+		if (!mbox_cmd->payload_out) {
+			kvfree(mbox_cmd->payload_in);
 			return -ENOMEM;
 		}
 	}
@@ -397,10 +396,8 @@ static void cxl_mbox_cmd_dtor(struct cxl_mbox_cmd *mbox)
 
 static int cxl_to_mem_cmd_raw(struct cxl_mem_command *mem_cmd,
 			      const struct cxl_send_command *send_cmd,
-			      struct cxl_memdev_state *mds)
+			      struct cxl_mailbox *cxl_mbox)
 {
-	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
-
 	if (send_cmd->raw.rsvd)
 		return -EINVAL;
 
@@ -415,7 +412,7 @@ static int cxl_to_mem_cmd_raw(struct cxl_mem_command *mem_cmd,
 	if (!cxl_mem_raw_command_allowed(send_cmd->raw.opcode))
 		return -EPERM;
 
-	dev_WARN_ONCE(mds->cxlds.dev, true, "raw command path used\n");
+	dev_WARN_ONCE(cxl_mbox->host, true, "raw command path used\n");
 
 	*mem_cmd = (struct cxl_mem_command) {
 		.info = {
@@ -431,7 +428,7 @@ static int cxl_to_mem_cmd_raw(struct cxl_mem_command *mem_cmd,
 
 static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd,
 			  const struct cxl_send_command *send_cmd,
-			  struct cxl_memdev_state *mds)
+			  struct cxl_mailbox *cxl_mbox)
 {
 	struct cxl_mem_command *c = &cxl_mem_commands[send_cmd->id];
 	const struct cxl_command_info *info = &c->info;
@@ -446,11 +443,11 @@ static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd,
 		return -EINVAL;
 
 	/* Check that the command is enabled for hardware */
-	if (!test_bit(info->id, mds->enabled_cmds))
+	if (!test_bit(info->id, cxl_mbox->enabled_cmds))
 		return -ENOTTY;
 
 	/* Check that the command is not claimed for exclusive kernel use */
-	if (test_bit(info->id, mds->exclusive_cmds))
+	if (test_bit(info->id, cxl_mbox->exclusive_cmds))
 		return -EBUSY;
 
 	/* Check the input buffer is the expected size */
@@ -479,7 +476,7 @@ static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd,
 /**
  * cxl_validate_cmd_from_user() - Check fields for CXL_MEM_SEND_COMMAND.
  * @mbox_cmd: Sanitized and populated &struct cxl_mbox_cmd.
- * @mds: The driver data for the operation
+ * @cxl_mbox: CXL mailbox context
  * @send_cmd: &struct cxl_send_command copied in from userspace.
  *
  * Return:
@@ -494,10 +491,9 @@ static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd,
  * safe to send to the hardware.
  */
 static int cxl_validate_cmd_from_user(struct cxl_mbox_cmd *mbox_cmd,
-				      struct cxl_memdev_state *mds,
+				      struct cxl_mailbox *cxl_mbox,
 				      const struct cxl_send_command *send_cmd)
 {
-	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
 	struct cxl_mem_command mem_cmd;
 	int rc;
 
@@ -514,24 +510,23 @@ static int cxl_validate_cmd_from_user(struct cxl_mbox_cmd *mbox_cmd,
 
 	/* Sanitize and construct a cxl_mem_command */
 	if (send_cmd->id == CXL_MEM_COMMAND_ID_RAW)
-		rc = cxl_to_mem_cmd_raw(&mem_cmd, send_cmd, mds);
+		rc = cxl_to_mem_cmd_raw(&mem_cmd, send_cmd, cxl_mbox);
 	else
-		rc = cxl_to_mem_cmd(&mem_cmd, send_cmd, mds);
+		rc = cxl_to_mem_cmd(&mem_cmd, send_cmd, cxl_mbox);
 
 	if (rc)
 		return rc;
 
 	/* Sanitize and construct a cxl_mbox_cmd */
-	return cxl_mbox_cmd_ctor(mbox_cmd, mds, mem_cmd.opcode,
+	return cxl_mbox_cmd_ctor(mbox_cmd, cxl_mbox, mem_cmd.opcode,
 				 mem_cmd.info.size_in, mem_cmd.info.size_out,
 				 send_cmd->in.payload);
 }
 
-int cxl_query_cmd(struct cxl_memdev *cxlmd,
+int cxl_query_cmd(struct cxl_mailbox *cxl_mbox,
 		  struct cxl_mem_query_commands __user *q)
 {
-	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
-	struct device *dev = &cxlmd->dev;
+	struct device *dev = cxl_mbox->host;
 	struct cxl_mem_command *cmd;
 	u32 n_commands;
 	int j = 0;
@@ -552,9 +547,9 @@ int cxl_query_cmd(struct cxl_memdev *cxlmd,
 	cxl_for_each_cmd(cmd) {
 		struct cxl_command_info info = cmd->info;
 
-		if (test_bit(info.id, mds->enabled_cmds))
+		if (test_bit(info.id, cxl_mbox->enabled_cmds))
 			info.flags |= CXL_MEM_COMMAND_FLAG_ENABLED;
-		if (test_bit(info.id, mds->exclusive_cmds))
+		if (test_bit(info.id, cxl_mbox->exclusive_cmds))
 			info.flags |= CXL_MEM_COMMAND_FLAG_EXCLUSIVE;
 
 		if (copy_to_user(&q->commands[j++], &info, sizeof(info)))
@@ -569,7 +564,7 @@ int cxl_query_cmd(struct cxl_memdev *cxlmd,
 
 /**
  * handle_mailbox_cmd_from_user() - Dispatch a mailbox command for userspace.
- * @mds: The driver data for the operation
+ * @cxl_mbox: The mailbox context for the operation.
  * @mbox_cmd: The validated mailbox command.
  * @out_payload: Pointer to userspace's output payload.
  * @size_out: (Input) Max payload size to copy out.
@@ -590,13 +585,12 @@ int cxl_query_cmd(struct cxl_memdev *cxlmd,
  *
  * See cxl_send_cmd().
  */
-static int handle_mailbox_cmd_from_user(struct cxl_memdev_state *mds,
+static int handle_mailbox_cmd_from_user(struct cxl_mailbox *cxl_mbox,
 					struct cxl_mbox_cmd *mbox_cmd,
 					u64 out_payload, s32 *size_out,
 					u32 *retval)
 {
-	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
-	struct device *dev = mds->cxlds.dev;
+	struct device *dev = cxl_mbox->host;
 	int rc;
 
 	dev_dbg(dev,
@@ -633,10 +627,9 @@ out:
 	return rc;
 }
 
-int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s)
+int cxl_send_cmd(struct cxl_mailbox *cxl_mbox, struct cxl_send_command __user *s)
 {
-	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
-	struct device *dev = &cxlmd->dev;
+	struct device *dev = cxl_mbox->host;
 	struct cxl_send_command send;
 	struct cxl_mbox_cmd mbox_cmd;
 	int rc;
@@ -646,11 +639,11 @@ int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s)
 	if (copy_from_user(&send, s, sizeof(send)))
 		return -EFAULT;
 
-	rc = cxl_validate_cmd_from_user(&mbox_cmd, mds, &send);
+	rc = cxl_validate_cmd_from_user(&mbox_cmd, cxl_mbox, &send);
 	if (rc)
 		return rc;
 
-	rc = handle_mailbox_cmd_from_user(mds, &mbox_cmd, send.out.payload,
+	rc = handle_mailbox_cmd_from_user(cxl_mbox, &mbox_cmd, send.out.payload,
 					  &send.out.size, &send.retval);
 	if (rc)
 		return rc;
@@ -713,6 +706,35 @@ static int cxl_xfer_log(struct cxl_memdev_state *mds, uuid_t *uuid,
 	return 0;
 }
 
+static int check_features_opcodes(u16 opcode, int *ro_cmds, int *wr_cmds)
+{
+	switch (opcode) {
+	case CXL_MBOX_OP_GET_SUPPORTED_FEATURES:
+	case CXL_MBOX_OP_GET_FEATURE:
+		(*ro_cmds)++;
+		return 1;
+	case CXL_MBOX_OP_SET_FEATURE:
+		(*wr_cmds)++;
+		return 1;
+	default:
+		return 0;
+	}
+}
+
+/* 'Get Supported Features' and 'Get Feature' */
+#define MAX_FEATURES_READ_CMDS	2
+static void set_features_cap(struct cxl_mailbox *cxl_mbox,
+			     int ro_cmds, int wr_cmds)
+{
+	/* Setting up Features capability while walking the CEL */
+	if (ro_cmds == MAX_FEATURES_READ_CMDS) {
+		if (wr_cmds)
+			cxl_mbox->feat_cap = CXL_FEATURES_RW;
+		else
+			cxl_mbox->feat_cap = CXL_FEATURES_RO;
+	}
+}
+
 /**
  * cxl_walk_cel() - Walk through the Command Effects Log.
  * @mds: The driver data for the operation
@@ -724,10 +746,11 @@ static int cxl_xfer_log(struct cxl_memdev_state *mds, uuid_t *uuid,
  */
 static void cxl_walk_cel(struct cxl_memdev_state *mds, size_t size, u8 *cel)
 {
+	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
 	struct cxl_cel_entry *cel_entry;
 	const int cel_entries = size / sizeof(*cel_entry);
 	struct device *dev = mds->cxlds.dev;
-	int i;
+	int i, ro_cmds = 0, wr_cmds = 0;
 
 	cel_entry = (struct cxl_cel_entry *) cel;
 
@@ -737,10 +760,13 @@ static void cxl_walk_cel(struct cxl_memdev_state *mds, size_t size, u8 *cel)
 		int enabled = 0;
 
 		if (cmd) {
-			set_bit(cmd->info.id, mds->enabled_cmds);
+			set_bit(cmd->info.id, cxl_mbox->enabled_cmds);
 			enabled++;
 		}
 
+		enabled += check_features_opcodes(opcode, &ro_cmds,
+						  &wr_cmds);
+
 		if (cxl_is_poison_command(opcode)) {
 			cxl_set_poison_cmd_enabled(&mds->poison, opcode);
 			enabled++;
@@ -754,6 +780,8 @@ static void cxl_walk_cel(struct cxl_memdev_state *mds, size_t size, u8 *cel)
 		dev_dbg(dev, "Opcode 0x%04x %s\n", opcode,
 			enabled ? "enabled" : "unsupported by driver");
 	}
+
+	set_features_cap(cxl_mbox, ro_cmds, wr_cmds);
 }
 
 static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct cxl_memdev_state *mds)
@@ -807,6 +835,7 @@ static const uuid_t log_uuid[] = {
  */
 int cxl_enumerate_cmds(struct cxl_memdev_state *mds)
 {
+	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
 	struct cxl_mbox_get_supported_logs *gsl;
 	struct device *dev = mds->cxlds.dev;
 	struct cxl_mem_command *cmd;
@@ -845,7 +874,7 @@ int cxl_enumerate_cmds(struct cxl_memdev_state *mds)
 		/* In case CEL was bogus, enable some default commands. */
 		cxl_for_each_cmd(cmd)
 			if (cmd->flags & CXL_CMD_FLAG_FORCE_ENABLE)
-				set_bit(cmd->info.id, mds->enabled_cmds);
+				set_bit(cmd->info.id, cxl_mbox->enabled_cmds);
 
 		/* Found the required CEL */
 		rc = 0;
@@ -1448,6 +1477,7 @@ struct cxl_memdev_state *cxl_memdev_state_create(struct device *dev)
 	mutex_init(&mds->event.log_lock);
 	mds->cxlds.dev = dev;
 	mds->cxlds.reg_map.host = dev;
+	mds->cxlds.cxl_mbox.host = dev;
 	mds->cxlds.reg_map.resource = CXL_RESOURCE_NONE;
 	mds->cxlds.type = CXL_DEVTYPE_CLASSMEM;
 	mds->ram_perf.qos_class = CXL_QOS_CLASS_INVALID;
diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
index ae3dfcb..2e2e035 100644
--- a/drivers/cxl/core/memdev.c
+++ b/drivers/cxl/core/memdev.c
@@ -564,9 +564,11 @@ EXPORT_SYMBOL_NS_GPL(is_cxl_memdev, "CXL");
 void set_exclusive_cxl_commands(struct cxl_memdev_state *mds,
 				unsigned long *cmds)
 {
+	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
+
 	down_write(&cxl_memdev_rwsem);
-	bitmap_or(mds->exclusive_cmds, mds->exclusive_cmds, cmds,
-		  CXL_MEM_COMMAND_ID_MAX);
+	bitmap_or(cxl_mbox->exclusive_cmds, cxl_mbox->exclusive_cmds,
+		  cmds, CXL_MEM_COMMAND_ID_MAX);
 	up_write(&cxl_memdev_rwsem);
 }
 EXPORT_SYMBOL_NS_GPL(set_exclusive_cxl_commands, "CXL");
@@ -579,9 +581,11 @@ EXPORT_SYMBOL_NS_GPL(set_exclusive_cxl_commands, "CXL");
 void clear_exclusive_cxl_commands(struct cxl_memdev_state *mds,
 				  unsigned long *cmds)
 {
+	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
+
 	down_write(&cxl_memdev_rwsem);
-	bitmap_andnot(mds->exclusive_cmds, mds->exclusive_cmds, cmds,
-		      CXL_MEM_COMMAND_ID_MAX);
+	bitmap_andnot(cxl_mbox->exclusive_cmds, cxl_mbox->exclusive_cmds,
+		      cmds, CXL_MEM_COMMAND_ID_MAX);
 	up_write(&cxl_memdev_rwsem);
 }
 EXPORT_SYMBOL_NS_GPL(clear_exclusive_cxl_commands, "CXL");
@@ -656,11 +660,14 @@ err:
 static long __cxl_memdev_ioctl(struct cxl_memdev *cxlmd, unsigned int cmd,
 			       unsigned long arg)
 {
+	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
+	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
+
 	switch (cmd) {
 	case CXL_MEM_QUERY_COMMANDS:
-		return cxl_query_cmd(cxlmd, (void __user *)arg);
+		return cxl_query_cmd(cxl_mbox, (void __user *)arg);
 	case CXL_MEM_SEND_COMMAND:
-		return cxl_send_cmd(cxlmd, (void __user *)arg);
+		return cxl_send_cmd(cxl_mbox, (void __user *)arg);
 	default:
 		return -ENOTTY;
 	}
@@ -994,10 +1001,11 @@ static void cxl_remove_fw_upload(void *fwl)
 int devm_cxl_setup_fw_upload(struct device *host, struct cxl_memdev_state *mds)
 {
 	struct cxl_dev_state *cxlds = &mds->cxlds;
+	struct cxl_mailbox *cxl_mbox = &cxlds->cxl_mbox;
 	struct device *dev = &cxlds->cxlmd->dev;
 	struct fw_upload *fwl;
 
-	if (!test_bit(CXL_MEM_COMMAND_ID_GET_FW_INFO, mds->enabled_cmds))
+	if (!test_bit(CXL_MEM_COMMAND_ID_GET_FW_INFO, cxl_mbox->enabled_cmds))
 		return 0;
 
 	fwl = firmware_upload_register(THIS_MODULE, dev, dev_name(dev),
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 2a25d19..dd2b706 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -106,42 +106,6 @@ static inline struct cxl_ep *cxl_ep_load(struct cxl_port *port,
 	return xa_load(&port->endpoints, (unsigned long)&cxlmd->dev);
 }
 
-/**
- * struct cxl_mbox_cmd - A command to be submitted to hardware.
- * @opcode: (input) The command set and command submitted to hardware.
- * @payload_in: (input) Pointer to the input payload.
- * @payload_out: (output) Pointer to the output payload. Must be allocated by
- *		 the caller.
- * @size_in: (input) Number of bytes to load from @payload_in.
- * @size_out: (input) Max number of bytes loaded into @payload_out.
- *            (output) Number of bytes generated by the device. For fixed size
- *            outputs commands this is always expected to be deterministic. For
- *            variable sized output commands, it tells the exact number of bytes
- *            written.
- * @min_out: (input) internal command output payload size validation
- * @poll_count: (input) Number of timeouts to attempt.
- * @poll_interval_ms: (input) Time between mailbox background command polling
- *                    interval timeouts.
- * @return_code: (output) Error code returned from hardware.
- *
- * This is the primary mechanism used to send commands to the hardware.
- * All the fields except @payload_* correspond exactly to the fields described in
- * Command Register section of the CXL 2.0 8.2.8.4.5. @payload_in and
- * @payload_out are written to, and read from the Command Payload Registers
- * defined in CXL 2.0 8.2.8.4.8.
- */
-struct cxl_mbox_cmd {
-	u16 opcode;
-	void *payload_in;
-	void *payload_out;
-	size_t size_in;
-	size_t size_out;
-	size_t min_out;
-	int poll_count;
-	int poll_interval_ms;
-	u16 return_code;
-};
-
 /*
  * Per CXL 3.0 Section 8.2.8.4.5.1
  */
@@ -428,6 +392,7 @@ struct cxl_dpa_perf {
  * @serial: PCIe Device Serial Number
  * @type: Generic Memory Class device or Vendor Specific Memory device
  * @cxl_mbox: CXL mailbox context
+ * @cxlfs: CXL features context
  */
 struct cxl_dev_state {
 	struct device *dev;
@@ -443,6 +408,9 @@ struct cxl_dev_state {
 	u64 serial;
 	enum cxl_devtype type;
 	struct cxl_mailbox cxl_mbox;
+#ifdef CONFIG_CXL_FEATURES
+	struct cxl_features_state *cxlfs;
+#endif
 };
 
 static inline struct cxl_dev_state *mbox_to_cxlds(struct cxl_mailbox *cxl_mbox)
@@ -461,8 +429,6 @@ static inline struct cxl_dev_state *mbox_to_cxlds(struct cxl_mailbox *cxl_mbox)
  * @lsa_size: Size of Label Storage Area
  *                (CXL 2.0 8.2.9.5.1.1 Identify Memory Device)
  * @firmware_version: Firmware version for the memory device.
- * @enabled_cmds: Hardware commands found enabled in CEL.
- * @exclusive_cmds: Commands that are kernel-internal only
  * @total_bytes: sum of all possible capacities
  * @volatile_only_bytes: hard volatile capacity
  * @persistent_only_bytes: hard persistent capacity
@@ -485,8 +451,6 @@ struct cxl_memdev_state {
 	struct cxl_dev_state cxlds;
 	size_t lsa_size;
 	char firmware_version[0x10];
-	DECLARE_BITMAP(enabled_cmds, CXL_MEM_COMMAND_ID_MAX);
-	DECLARE_BITMAP(exclusive_cmds, CXL_MEM_COMMAND_ID_MAX);
 	u64 total_bytes;
 	u64 volatile_only_bytes;
 	u64 persistent_only_bytes;
@@ -530,6 +494,9 @@ enum cxl_opcode {
 	CXL_MBOX_OP_GET_LOG_CAPS	= 0x0402,
 	CXL_MBOX_OP_CLEAR_LOG           = 0x0403,
 	CXL_MBOX_OP_GET_SUP_LOG_SUBLIST = 0x0405,
+	CXL_MBOX_OP_GET_SUPPORTED_FEATURES	= 0x0500,
+	CXL_MBOX_OP_GET_FEATURE		= 0x0501,
+	CXL_MBOX_OP_SET_FEATURE		= 0x0502,
 	CXL_MBOX_OP_IDENTIFY		= 0x4000,
 	CXL_MBOX_OP_GET_PARTITION_INFO	= 0x4100,
 	CXL_MBOX_OP_SET_PARTITION_INFO	= 0x4101,
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index a96e54c..993fa60 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -997,6 +997,10 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	if (rc)
 		return rc;
 
+	rc = devm_cxl_setup_features(cxlds);
+	if (rc)
+		dev_dbg(&pdev->dev, "No CXL Features discovered\n");
+
 	cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlds);
 	if (IS_ERR(cxlmd))
 		return PTR_ERR(cxlmd);
@@ -1009,6 +1013,10 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	if (rc)
 		return rc;
 
+	rc = devm_cxl_setup_fwctl(cxlmd);
+	if (rc)
+		dev_dbg(&pdev->dev, "No CXL FWCTL setup\n");
+
 	pmu_count = cxl_count_regblock(pdev, CXL_REGLOC_RBI_PMU);
 	if (pmu_count < 0)
 		return pmu_count;
diff --git a/drivers/fwctl/Kconfig b/drivers/fwctl/Kconfig
new file mode 100644
index 0000000..b5583b1
--- /dev/null
+++ b/drivers/fwctl/Kconfig
@@ -0,0 +1,33 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig FWCTL
+	tristate "fwctl device firmware access framework"
+	help
+	  fwctl provides a userspace API for restricted access to communicate
+	  with on-device firmware. The communication channel is intended to
+	  support a wide range of lockdown compatible device behaviors including
+	  manipulating device FLASH, debugging, and other activities that don't
+	  fit neatly into an existing subsystem.
+
+if FWCTL
+config FWCTL_MLX5
+	tristate "mlx5 ConnectX control fwctl driver"
+	depends on MLX5_CORE
+	help
+	  MLX5 provides interface for the user process to access the debug and
+	  configuration registers of the ConnectX hardware family
+	  (NICs, PCI switches and SmartNIC SoCs).
+	  This will allow configuration and debug tools to work out of the box on
+	  mainstream kernel.
+
+	  If you don't know what to do here, say N.
+
+config FWCTL_PDS
+	tristate "AMD/Pensando pds fwctl driver"
+	depends on PDS_CORE
+	help
+	  The pds_fwctl driver provides an fwctl interface for a user process
+	  to access the debug and configuration information of the AMD/Pensando
+	  DSC hardware family.
+
+	  If you don't know what to do here, say N.
+endif
diff --git a/drivers/fwctl/Makefile b/drivers/fwctl/Makefile
new file mode 100644
index 0000000..c093b5f
--- /dev/null
+++ b/drivers/fwctl/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_FWCTL) += fwctl.o
+obj-$(CONFIG_FWCTL_MLX5) += mlx5/
+obj-$(CONFIG_FWCTL_PDS) += pds/
+
+fwctl-y += main.o
diff --git a/drivers/fwctl/main.c b/drivers/fwctl/main.c
new file mode 100644
index 0000000..cb1ac9c
--- /dev/null
+++ b/drivers/fwctl/main.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024-2025, NVIDIA CORPORATION & AFFILIATES
+ */
+#define pr_fmt(fmt) "fwctl: " fmt
+#include <linux/fwctl.h>
+
+#include <linux/container_of.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+
+#include <uapi/fwctl/fwctl.h>
+
+enum {
+	FWCTL_MAX_DEVICES = 4096,
+	MAX_RPC_LEN = SZ_2M,
+};
+static_assert(FWCTL_MAX_DEVICES < (1U << MINORBITS));
+
+static dev_t fwctl_dev;
+static DEFINE_IDA(fwctl_ida);
+static unsigned long fwctl_tainted;
+
+struct fwctl_ucmd {
+	struct fwctl_uctx *uctx;
+	void __user *ubuffer;
+	void *cmd;
+	u32 user_size;
+};
+
+static int ucmd_respond(struct fwctl_ucmd *ucmd, size_t cmd_len)
+{
+	if (copy_to_user(ucmd->ubuffer, ucmd->cmd,
+			 min_t(size_t, ucmd->user_size, cmd_len)))
+		return -EFAULT;
+	return 0;
+}
+
+static int copy_to_user_zero_pad(void __user *to, const void *from,
+				 size_t from_len, size_t user_len)
+{
+	size_t copy_len;
+
+	copy_len = min(from_len, user_len);
+	if (copy_to_user(to, from, copy_len))
+		return -EFAULT;
+	if (copy_len < user_len) {
+		if (clear_user(to + copy_len, user_len - copy_len))
+			return -EFAULT;
+	}
+	return 0;
+}
+
+static int fwctl_cmd_info(struct fwctl_ucmd *ucmd)
+{
+	struct fwctl_device *fwctl = ucmd->uctx->fwctl;
+	struct fwctl_info *cmd = ucmd->cmd;
+	size_t driver_info_len = 0;
+
+	if (cmd->flags)
+		return -EOPNOTSUPP;
+
+	if (!fwctl->ops->info && cmd->device_data_len) {
+		if (clear_user(u64_to_user_ptr(cmd->out_device_data),
+			       cmd->device_data_len))
+			return -EFAULT;
+	} else if (cmd->device_data_len) {
+		void *driver_info __free(kfree) =
+			fwctl->ops->info(ucmd->uctx, &driver_info_len);
+		if (IS_ERR(driver_info))
+			return PTR_ERR(driver_info);
+
+		if (copy_to_user_zero_pad(u64_to_user_ptr(cmd->out_device_data),
+					  driver_info, driver_info_len,
+					  cmd->device_data_len))
+			return -EFAULT;
+	}
+
+	cmd->out_device_type = fwctl->ops->device_type;
+	cmd->device_data_len = driver_info_len;
+	return ucmd_respond(ucmd, sizeof(*cmd));
+}
+
+static int fwctl_cmd_rpc(struct fwctl_ucmd *ucmd)
+{
+	struct fwctl_device *fwctl = ucmd->uctx->fwctl;
+	struct fwctl_rpc *cmd = ucmd->cmd;
+	size_t out_len;
+
+	if (cmd->in_len > MAX_RPC_LEN || cmd->out_len > MAX_RPC_LEN)
+		return -EMSGSIZE;
+
+	switch (cmd->scope) {
+	case FWCTL_RPC_CONFIGURATION:
+	case FWCTL_RPC_DEBUG_READ_ONLY:
+		break;
+
+	case FWCTL_RPC_DEBUG_WRITE_FULL:
+		if (!capable(CAP_SYS_RAWIO))
+			return -EPERM;
+		fallthrough;
+	case FWCTL_RPC_DEBUG_WRITE:
+		if (!test_and_set_bit(0, &fwctl_tainted)) {
+			dev_warn(
+				&fwctl->dev,
+				"%s(%d): has requested full access to the physical device device",
+				current->comm, task_pid_nr(current));
+			add_taint(TAINT_FWCTL, LOCKDEP_STILL_OK);
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	void *inbuf __free(kvfree) = kvzalloc(cmd->in_len, GFP_KERNEL_ACCOUNT);
+	if (!inbuf)
+		return -ENOMEM;
+	if (copy_from_user(inbuf, u64_to_user_ptr(cmd->in), cmd->in_len))
+		return -EFAULT;
+
+	out_len = cmd->out_len;
+	void *outbuf __free(kvfree) = fwctl->ops->fw_rpc(
+		ucmd->uctx, cmd->scope, inbuf, cmd->in_len, &out_len);
+	if (IS_ERR(outbuf))
+		return PTR_ERR(outbuf);
+	if (outbuf == inbuf) {
+		/* The driver can re-use inbuf as outbuf */
+		inbuf = NULL;
+	}
+
+	if (copy_to_user(u64_to_user_ptr(cmd->out), outbuf,
+			 min(cmd->out_len, out_len)))
+		return -EFAULT;
+
+	cmd->out_len = out_len;
+	return ucmd_respond(ucmd, sizeof(*cmd));
+}
+
+/* On stack memory for the ioctl structs */
+union fwctl_ucmd_buffer {
+	struct fwctl_info info;
+	struct fwctl_rpc rpc;
+};
+
+struct fwctl_ioctl_op {
+	unsigned int size;
+	unsigned int min_size;
+	unsigned int ioctl_num;
+	int (*execute)(struct fwctl_ucmd *ucmd);
+};
+
+#define IOCTL_OP(_ioctl, _fn, _struct, _last)                               \
+	[_IOC_NR(_ioctl) - FWCTL_CMD_BASE] = {                              \
+		.size = sizeof(_struct) +                                   \
+			BUILD_BUG_ON_ZERO(sizeof(union fwctl_ucmd_buffer) < \
+					  sizeof(_struct)),                 \
+		.min_size = offsetofend(_struct, _last),                    \
+		.ioctl_num = _ioctl,                                        \
+		.execute = _fn,                                             \
+	}
+static const struct fwctl_ioctl_op fwctl_ioctl_ops[] = {
+	IOCTL_OP(FWCTL_INFO, fwctl_cmd_info, struct fwctl_info, out_device_data),
+	IOCTL_OP(FWCTL_RPC, fwctl_cmd_rpc, struct fwctl_rpc, out),
+};
+
+static long fwctl_fops_ioctl(struct file *filp, unsigned int cmd,
+			       unsigned long arg)
+{
+	struct fwctl_uctx *uctx = filp->private_data;
+	const struct fwctl_ioctl_op *op;
+	struct fwctl_ucmd ucmd = {};
+	union fwctl_ucmd_buffer buf;
+	unsigned int nr;
+	int ret;
+
+	nr = _IOC_NR(cmd);
+	if ((nr - FWCTL_CMD_BASE) >= ARRAY_SIZE(fwctl_ioctl_ops))
+		return -ENOIOCTLCMD;
+
+	op = &fwctl_ioctl_ops[nr - FWCTL_CMD_BASE];
+	if (op->ioctl_num != cmd)
+		return -ENOIOCTLCMD;
+
+	ucmd.uctx = uctx;
+	ucmd.cmd = &buf;
+	ucmd.ubuffer = (void __user *)arg;
+	ret = get_user(ucmd.user_size, (u32 __user *)ucmd.ubuffer);
+	if (ret)
+		return ret;
+
+	if (ucmd.user_size < op->min_size)
+		return -EINVAL;
+
+	ret = copy_struct_from_user(ucmd.cmd, op->size, ucmd.ubuffer,
+				    ucmd.user_size);
+	if (ret)
+		return ret;
+
+	guard(rwsem_read)(&uctx->fwctl->registration_lock);
+	if (!uctx->fwctl->ops)
+		return -ENODEV;
+	return op->execute(&ucmd);
+}
+
+static int fwctl_fops_open(struct inode *inode, struct file *filp)
+{
+	struct fwctl_device *fwctl =
+		container_of(inode->i_cdev, struct fwctl_device, cdev);
+	int ret;
+
+	guard(rwsem_read)(&fwctl->registration_lock);
+	if (!fwctl->ops)
+		return -ENODEV;
+
+	struct fwctl_uctx *uctx __free(kfree) =
+		kzalloc(fwctl->ops->uctx_size, GFP_KERNEL_ACCOUNT);
+	if (!uctx)
+		return -ENOMEM;
+
+	uctx->fwctl = fwctl;
+	ret = fwctl->ops->open_uctx(uctx);
+	if (ret)
+		return ret;
+
+	scoped_guard(mutex, &fwctl->uctx_list_lock) {
+		list_add_tail(&uctx->uctx_list_entry, &fwctl->uctx_list);
+	}
+
+	get_device(&fwctl->dev);
+	filp->private_data = no_free_ptr(uctx);
+	return 0;
+}
+
+static void fwctl_destroy_uctx(struct fwctl_uctx *uctx)
+{
+	lockdep_assert_held(&uctx->fwctl->uctx_list_lock);
+	list_del(&uctx->uctx_list_entry);
+	uctx->fwctl->ops->close_uctx(uctx);
+}
+
+static int fwctl_fops_release(struct inode *inode, struct file *filp)
+{
+	struct fwctl_uctx *uctx = filp->private_data;
+	struct fwctl_device *fwctl = uctx->fwctl;
+
+	scoped_guard(rwsem_read, &fwctl->registration_lock) {
+		/*
+		 * NULL ops means fwctl_unregister() has already removed the
+		 * driver and destroyed the uctx.
+		 */
+		if (fwctl->ops) {
+			guard(mutex)(&fwctl->uctx_list_lock);
+			fwctl_destroy_uctx(uctx);
+		}
+	}
+
+	kfree(uctx);
+	fwctl_put(fwctl);
+	return 0;
+}
+
+static const struct file_operations fwctl_fops = {
+	.owner = THIS_MODULE,
+	.open = fwctl_fops_open,
+	.release = fwctl_fops_release,
+	.unlocked_ioctl = fwctl_fops_ioctl,
+};
+
+static void fwctl_device_release(struct device *device)
+{
+	struct fwctl_device *fwctl =
+		container_of(device, struct fwctl_device, dev);
+
+	ida_free(&fwctl_ida, fwctl->dev.devt - fwctl_dev);
+	mutex_destroy(&fwctl->uctx_list_lock);
+	kfree(fwctl);
+}
+
+static char *fwctl_devnode(const struct device *dev, umode_t *mode)
+{
+	return kasprintf(GFP_KERNEL, "fwctl/%s", dev_name(dev));
+}
+
+static struct class fwctl_class = {
+	.name = "fwctl",
+	.dev_release = fwctl_device_release,
+	.devnode = fwctl_devnode,
+};
+
+static struct fwctl_device *
+_alloc_device(struct device *parent, const struct fwctl_ops *ops, size_t size)
+{
+	struct fwctl_device *fwctl __free(kfree) = kzalloc(size, GFP_KERNEL);
+	int devnum;
+
+	if (!fwctl)
+		return NULL;
+
+	devnum = ida_alloc_max(&fwctl_ida, FWCTL_MAX_DEVICES - 1, GFP_KERNEL);
+	if (devnum < 0)
+		return NULL;
+
+	fwctl->dev.devt = fwctl_dev + devnum;
+	fwctl->dev.class = &fwctl_class;
+	fwctl->dev.parent = parent;
+
+	init_rwsem(&fwctl->registration_lock);
+	mutex_init(&fwctl->uctx_list_lock);
+	INIT_LIST_HEAD(&fwctl->uctx_list);
+
+	device_initialize(&fwctl->dev);
+	return_ptr(fwctl);
+}
+
+/* Drivers use the fwctl_alloc_device() wrapper */
+struct fwctl_device *_fwctl_alloc_device(struct device *parent,
+					 const struct fwctl_ops *ops,
+					 size_t size)
+{
+	struct fwctl_device *fwctl __free(fwctl) =
+		_alloc_device(parent, ops, size);
+
+	if (!fwctl)
+		return NULL;
+
+	cdev_init(&fwctl->cdev, &fwctl_fops);
+	/*
+	 * The driver module is protected by fwctl_register/unregister(),
+	 * unregister won't complete until we are done with the driver's module.
+	 */
+	fwctl->cdev.owner = THIS_MODULE;
+
+	if (dev_set_name(&fwctl->dev, "fwctl%d", fwctl->dev.devt - fwctl_dev))
+		return NULL;
+
+	fwctl->ops = ops;
+	return_ptr(fwctl);
+}
+EXPORT_SYMBOL_NS_GPL(_fwctl_alloc_device, "FWCTL");
+
+/**
+ * fwctl_register - Register a new device to the subsystem
+ * @fwctl: Previously allocated fwctl_device
+ *
+ * On return the device is visible through sysfs and /dev, driver ops may be
+ * called.
+ */
+int fwctl_register(struct fwctl_device *fwctl)
+{
+	return cdev_device_add(&fwctl->cdev, &fwctl->dev);
+}
+EXPORT_SYMBOL_NS_GPL(fwctl_register, "FWCTL");
+
+/**
+ * fwctl_unregister - Unregister a device from the subsystem
+ * @fwctl: Previously allocated and registered fwctl_device
+ *
+ * Undoes fwctl_register(). On return no driver ops will be called. The
+ * caller must still call fwctl_put() to free the fwctl.
+ *
+ * Unregister will return even if userspace still has file descriptors open.
+ * This will call ops->close_uctx() on any open FDs and after return no driver
+ * op will be called. The FDs remain open but all fops will return -ENODEV.
+ *
+ * The design of fwctl allows this sort of disassociation of the driver from the
+ * subsystem primarily by keeping memory allocations owned by the core subsytem.
+ * The fwctl_device and fwctl_uctx can both be freed without requiring a driver
+ * callback. This allows the module to remain unlocked while FDs are open.
+ */
+void fwctl_unregister(struct fwctl_device *fwctl)
+{
+	struct fwctl_uctx *uctx;
+
+	cdev_device_del(&fwctl->cdev, &fwctl->dev);
+
+	/* Disable and free the driver's resources for any still open FDs. */
+	guard(rwsem_write)(&fwctl->registration_lock);
+	guard(mutex)(&fwctl->uctx_list_lock);
+	while ((uctx = list_first_entry_or_null(&fwctl->uctx_list,
+						struct fwctl_uctx,
+						uctx_list_entry)))
+		fwctl_destroy_uctx(uctx);
+
+	/*
+	 * The driver module may unload after this returns, the op pointer will
+	 * not be valid.
+	 */
+	fwctl->ops = NULL;
+}
+EXPORT_SYMBOL_NS_GPL(fwctl_unregister, "FWCTL");
+
+static int __init fwctl_init(void)
+{
+	int ret;
+
+	ret = alloc_chrdev_region(&fwctl_dev, 0, FWCTL_MAX_DEVICES, "fwctl");
+	if (ret)
+		return ret;
+
+	ret = class_register(&fwctl_class);
+	if (ret)
+		goto err_chrdev;
+	return 0;
+
+err_chrdev:
+	unregister_chrdev_region(fwctl_dev, FWCTL_MAX_DEVICES);
+	return ret;
+}
+
+static void __exit fwctl_exit(void)
+{
+	class_unregister(&fwctl_class);
+	unregister_chrdev_region(fwctl_dev, FWCTL_MAX_DEVICES);
+}
+
+module_init(fwctl_init);
+module_exit(fwctl_exit);
+MODULE_DESCRIPTION("fwctl device firmware access framework");
+MODULE_LICENSE("GPL");
diff --git a/drivers/fwctl/mlx5/Makefile b/drivers/fwctl/mlx5/Makefile
new file mode 100644
index 0000000..139a23e
--- /dev/null
+++ b/drivers/fwctl/mlx5/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_FWCTL_MLX5) += mlx5_fwctl.o
+
+mlx5_fwctl-y += main.o
diff --git a/drivers/fwctl/mlx5/main.c b/drivers/fwctl/mlx5/main.c
new file mode 100644
index 0000000..f93aa0c
--- /dev/null
+++ b/drivers/fwctl/mlx5/main.c
@@ -0,0 +1,411 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/*
+ * Copyright (c) 2024-2025, NVIDIA CORPORATION & AFFILIATES
+ */
+#include <linux/fwctl.h>
+#include <linux/auxiliary_bus.h>
+#include <linux/mlx5/device.h>
+#include <linux/mlx5/driver.h>
+#include <uapi/fwctl/mlx5.h>
+
+#define mlx5ctl_err(mcdev, format, ...) \
+	dev_err(&mcdev->fwctl.dev, format, ##__VA_ARGS__)
+
+#define mlx5ctl_dbg(mcdev, format, ...)                             \
+	dev_dbg(&mcdev->fwctl.dev, "PID %u: " format, current->pid, \
+		##__VA_ARGS__)
+
+struct mlx5ctl_uctx {
+	struct fwctl_uctx uctx;
+	u32 uctx_caps;
+	u32 uctx_uid;
+};
+
+struct mlx5ctl_dev {
+	struct fwctl_device fwctl;
+	struct mlx5_core_dev *mdev;
+};
+DEFINE_FREE(mlx5ctl, struct mlx5ctl_dev *, if (_T) fwctl_put(&_T->fwctl));
+
+struct mlx5_ifc_mbox_in_hdr_bits {
+	u8 opcode[0x10];
+	u8 uid[0x10];
+
+	u8 reserved_at_20[0x10];
+	u8 op_mod[0x10];
+
+	u8 reserved_at_40[0x40];
+};
+
+struct mlx5_ifc_mbox_out_hdr_bits {
+	u8 status[0x8];
+	u8 reserved_at_8[0x18];
+
+	u8 syndrome[0x20];
+
+	u8 reserved_at_40[0x40];
+};
+
+enum {
+	MLX5_UCTX_OBJECT_CAP_TOOLS_RESOURCES = 0x4,
+};
+
+enum {
+	MLX5_CMD_OP_QUERY_DRIVER_VERSION = 0x10c,
+	MLX5_CMD_OP_QUERY_OTHER_HCA_CAP = 0x10e,
+	MLX5_CMD_OP_QUERY_RDB = 0x512,
+	MLX5_CMD_OP_QUERY_PSV = 0x602,
+	MLX5_CMD_OP_QUERY_DC_CNAK_TRACE = 0x716,
+	MLX5_CMD_OP_QUERY_NVMF_BACKEND_CONTROLLER = 0x722,
+	MLX5_CMD_OP_QUERY_NVMF_NAMESPACE_CONTEXT = 0x728,
+	MLX5_CMD_OP_QUERY_BURST_SIZE = 0x813,
+	MLX5_CMD_OP_QUERY_DIAGNOSTIC_PARAMS = 0x819,
+	MLX5_CMD_OP_SET_DIAGNOSTIC_PARAMS = 0x820,
+	MLX5_CMD_OP_QUERY_DIAGNOSTIC_COUNTERS = 0x821,
+	MLX5_CMD_OP_QUERY_DELAY_DROP_PARAMS = 0x911,
+	MLX5_CMD_OP_QUERY_AFU = 0x971,
+	MLX5_CMD_OP_QUERY_CAPI_PEC = 0x981,
+	MLX5_CMD_OP_QUERY_UCTX = 0xa05,
+	MLX5_CMD_OP_QUERY_UMEM = 0xa09,
+	MLX5_CMD_OP_QUERY_NVMF_CC_RESPONSE = 0xb02,
+	MLX5_CMD_OP_QUERY_EMULATED_FUNCTIONS_INFO = 0xb03,
+	MLX5_CMD_OP_QUERY_REGEXP_PARAMS = 0xb05,
+	MLX5_CMD_OP_QUERY_REGEXP_REGISTER = 0xb07,
+	MLX5_CMD_OP_USER_QUERY_XRQ_DC_PARAMS_ENTRY = 0xb08,
+	MLX5_CMD_OP_USER_QUERY_XRQ_ERROR_PARAMS = 0xb0a,
+	MLX5_CMD_OP_ACCESS_REGISTER_USER = 0xb0c,
+	MLX5_CMD_OP_QUERY_EMULATION_DEVICE_EQ_MSIX_MAPPING = 0xb0f,
+	MLX5_CMD_OP_QUERY_MATCH_SAMPLE_INFO = 0xb13,
+	MLX5_CMD_OP_QUERY_CRYPTO_STATE = 0xb14,
+	MLX5_CMD_OP_QUERY_VUID = 0xb22,
+	MLX5_CMD_OP_QUERY_DPA_PARTITION = 0xb28,
+	MLX5_CMD_OP_QUERY_DPA_PARTITIONS = 0xb2a,
+	MLX5_CMD_OP_POSTPONE_CONNECTED_QP_TIMEOUT = 0xb2e,
+	MLX5_CMD_OP_QUERY_EMULATED_RESOURCES_INFO = 0xb2f,
+	MLX5_CMD_OP_QUERY_RSV_RESOURCES = 0x8000,
+	MLX5_CMD_OP_QUERY_MTT = 0x8001,
+	MLX5_CMD_OP_QUERY_SCHED_QUEUE = 0x8006,
+};
+
+static int mlx5ctl_alloc_uid(struct mlx5ctl_dev *mcdev, u32 cap)
+{
+	u32 out[MLX5_ST_SZ_DW(create_uctx_out)] = {};
+	u32 in[MLX5_ST_SZ_DW(create_uctx_in)] = {};
+	void *uctx;
+	int ret;
+	u16 uid;
+
+	uctx = MLX5_ADDR_OF(create_uctx_in, in, uctx);
+
+	mlx5ctl_dbg(mcdev, "%s: caps 0x%x\n", __func__, cap);
+	MLX5_SET(create_uctx_in, in, opcode, MLX5_CMD_OP_CREATE_UCTX);
+	MLX5_SET(uctx, uctx, cap, cap);
+
+	ret = mlx5_cmd_exec(mcdev->mdev, in, sizeof(in), out, sizeof(out));
+	if (ret)
+		return ret;
+
+	uid = MLX5_GET(create_uctx_out, out, uid);
+	mlx5ctl_dbg(mcdev, "allocated uid %u with caps 0x%x\n", uid, cap);
+	return uid;
+}
+
+static void mlx5ctl_release_uid(struct mlx5ctl_dev *mcdev, u16 uid)
+{
+	u32 in[MLX5_ST_SZ_DW(destroy_uctx_in)] = {};
+	struct mlx5_core_dev *mdev = mcdev->mdev;
+	int ret;
+
+	MLX5_SET(destroy_uctx_in, in, opcode, MLX5_CMD_OP_DESTROY_UCTX);
+	MLX5_SET(destroy_uctx_in, in, uid, uid);
+
+	ret = mlx5_cmd_exec_in(mdev, destroy_uctx, in);
+	mlx5ctl_dbg(mcdev, "released uid %u %pe\n", uid, ERR_PTR(ret));
+}
+
+static int mlx5ctl_open_uctx(struct fwctl_uctx *uctx)
+{
+	struct mlx5ctl_uctx *mfd =
+		container_of(uctx, struct mlx5ctl_uctx, uctx);
+	struct mlx5ctl_dev *mcdev =
+		container_of(uctx->fwctl, struct mlx5ctl_dev, fwctl);
+	int uid;
+
+	/*
+	 * New FW supports the TOOLS_RESOURCES uid security label
+	 * which allows commands to manipulate the global device state.
+	 * Otherwise only basic existing RDMA devx privilege are allowed.
+	 */
+	if (MLX5_CAP_GEN(mcdev->mdev, uctx_cap) &
+	    MLX5_UCTX_OBJECT_CAP_TOOLS_RESOURCES)
+		mfd->uctx_caps |= MLX5_UCTX_OBJECT_CAP_TOOLS_RESOURCES;
+
+	uid = mlx5ctl_alloc_uid(mcdev, mfd->uctx_caps);
+	if (uid < 0)
+		return uid;
+
+	mfd->uctx_uid = uid;
+	return 0;
+}
+
+static void mlx5ctl_close_uctx(struct fwctl_uctx *uctx)
+{
+	struct mlx5ctl_dev *mcdev =
+		container_of(uctx->fwctl, struct mlx5ctl_dev, fwctl);
+	struct mlx5ctl_uctx *mfd =
+		container_of(uctx, struct mlx5ctl_uctx, uctx);
+
+	mlx5ctl_release_uid(mcdev, mfd->uctx_uid);
+}
+
+static void *mlx5ctl_info(struct fwctl_uctx *uctx, size_t *length)
+{
+	struct mlx5ctl_uctx *mfd =
+		container_of(uctx, struct mlx5ctl_uctx, uctx);
+	struct fwctl_info_mlx5 *info;
+
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return ERR_PTR(-ENOMEM);
+
+	info->uid = mfd->uctx_uid;
+	info->uctx_caps = mfd->uctx_caps;
+	*length = sizeof(*info);
+	return info;
+}
+
+static bool mlx5ctl_validate_rpc(const void *in, enum fwctl_rpc_scope scope)
+{
+	u16 opcode = MLX5_GET(mbox_in_hdr, in, opcode);
+	u16 op_mod = MLX5_GET(mbox_in_hdr, in, op_mod);
+
+	/*
+	 * Currently the driver can't keep track of commands that allocate
+	 * objects in the FW, these commands are safe from a security
+	 * perspective but nothing will free the memory when the FD is closed.
+	 * For now permit only query commands and set commands that don't alter
+	 * objects. Also the caps for the scope have not been defined yet,
+	 * filter commands manually for now.
+	 */
+	switch (opcode) {
+	case MLX5_CMD_OP_POSTPONE_CONNECTED_QP_TIMEOUT:
+	case MLX5_CMD_OP_QUERY_ADAPTER:
+	case MLX5_CMD_OP_QUERY_ESW_FUNCTIONS:
+	case MLX5_CMD_OP_QUERY_HCA_CAP:
+	case MLX5_CMD_OP_QUERY_HCA_VPORT_CONTEXT:
+	case MLX5_CMD_OP_QUERY_OTHER_HCA_CAP:
+	case MLX5_CMD_OP_QUERY_ROCE_ADDRESS:
+	case MLX5_CMD_OPCODE_QUERY_VUID:
+	/*
+	 * FW limits SET_HCA_CAP on the tools UID to only the other function
+	 * mode which is used for function pre-configuration
+	 */
+	case MLX5_CMD_OP_SET_HCA_CAP:
+		return true; /* scope >= FWCTL_RPC_CONFIGURATION; */
+
+	case MLX5_CMD_OP_FPGA_QUERY_QP_COUNTERS:
+	case MLX5_CMD_OP_FPGA_QUERY_QP:
+	case MLX5_CMD_OP_NOP:
+	case MLX5_CMD_OP_QUERY_AFU:
+	case MLX5_CMD_OP_QUERY_BURST_SIZE:
+	case MLX5_CMD_OP_QUERY_CAPI_PEC:
+	case MLX5_CMD_OP_QUERY_CONG_PARAMS:
+	case MLX5_CMD_OP_QUERY_CONG_STATISTICS:
+	case MLX5_CMD_OP_QUERY_CONG_STATUS:
+	case MLX5_CMD_OP_QUERY_CQ:
+	case MLX5_CMD_OP_QUERY_CRYPTO_STATE:
+	case MLX5_CMD_OP_QUERY_DC_CNAK_TRACE:
+	case MLX5_CMD_OP_QUERY_DCT:
+	case MLX5_CMD_OP_QUERY_DELAY_DROP_PARAMS:
+	case MLX5_CMD_OP_QUERY_DIAGNOSTIC_COUNTERS:
+	case MLX5_CMD_OP_QUERY_DIAGNOSTIC_PARAMS:
+	case MLX5_CMD_OP_QUERY_DPA_PARTITION:
+	case MLX5_CMD_OP_QUERY_DPA_PARTITIONS:
+	case MLX5_CMD_OP_QUERY_DRIVER_VERSION:
+	case MLX5_CMD_OP_QUERY_EMULATED_FUNCTIONS_INFO:
+	case MLX5_CMD_OP_QUERY_EMULATED_RESOURCES_INFO:
+	case MLX5_CMD_OP_QUERY_EMULATION_DEVICE_EQ_MSIX_MAPPING:
+	case MLX5_CMD_OP_QUERY_EQ:
+	case MLX5_CMD_OP_QUERY_ESW_VPORT_CONTEXT:
+	case MLX5_CMD_OP_QUERY_FLOW_COUNTER:
+	case MLX5_CMD_OP_QUERY_FLOW_GROUP:
+	case MLX5_CMD_OP_QUERY_FLOW_TABLE_ENTRY:
+	case MLX5_CMD_OP_QUERY_FLOW_TABLE:
+	case MLX5_CMD_OP_QUERY_GENERAL_OBJECT:
+	case MLX5_CMD_OP_QUERY_HCA_VPORT_GID:
+	case MLX5_CMD_OP_QUERY_HCA_VPORT_PKEY:
+	case MLX5_CMD_OP_QUERY_ISSI:
+	case MLX5_CMD_OP_QUERY_L2_TABLE_ENTRY:
+	case MLX5_CMD_OP_QUERY_LAG:
+	case MLX5_CMD_OP_QUERY_MAD_DEMUX:
+	case MLX5_CMD_OP_QUERY_MATCH_SAMPLE_INFO:
+	case MLX5_CMD_OP_QUERY_MKEY:
+	case MLX5_CMD_OP_QUERY_MODIFY_HEADER_CONTEXT:
+	case MLX5_CMD_OP_QUERY_MTT:
+	case MLX5_CMD_OP_QUERY_NIC_VPORT_CONTEXT:
+	case MLX5_CMD_OP_QUERY_NVMF_BACKEND_CONTROLLER:
+	case MLX5_CMD_OP_QUERY_NVMF_CC_RESPONSE:
+	case MLX5_CMD_OP_QUERY_NVMF_NAMESPACE_CONTEXT:
+	case MLX5_CMD_OP_QUERY_PACKET_REFORMAT_CONTEXT:
+	case MLX5_CMD_OP_QUERY_PAGES:
+	case MLX5_CMD_OP_QUERY_PSV:
+	case MLX5_CMD_OP_QUERY_Q_COUNTER:
+	case MLX5_CMD_OP_QUERY_QP:
+	case MLX5_CMD_OP_QUERY_RATE_LIMIT:
+	case MLX5_CMD_OP_QUERY_RDB:
+	case MLX5_CMD_OP_QUERY_REGEXP_PARAMS:
+	case MLX5_CMD_OP_QUERY_REGEXP_REGISTER:
+	case MLX5_CMD_OP_QUERY_RMP:
+	case MLX5_CMD_OP_QUERY_RQ:
+	case MLX5_CMD_OP_QUERY_RQT:
+	case MLX5_CMD_OP_QUERY_RSV_RESOURCES:
+	case MLX5_CMD_OP_QUERY_SCHED_QUEUE:
+	case MLX5_CMD_OP_QUERY_SCHEDULING_ELEMENT:
+	case MLX5_CMD_OP_QUERY_SF_PARTITION:
+	case MLX5_CMD_OP_QUERY_SPECIAL_CONTEXTS:
+	case MLX5_CMD_OP_QUERY_SQ:
+	case MLX5_CMD_OP_QUERY_SRQ:
+	case MLX5_CMD_OP_QUERY_TIR:
+	case MLX5_CMD_OP_QUERY_TIS:
+	case MLX5_CMD_OP_QUERY_UCTX:
+	case MLX5_CMD_OP_QUERY_UMEM:
+	case MLX5_CMD_OP_QUERY_VHCA_MIGRATION_STATE:
+	case MLX5_CMD_OP_QUERY_VHCA_STATE:
+	case MLX5_CMD_OP_QUERY_VNIC_ENV:
+	case MLX5_CMD_OP_QUERY_VPORT_COUNTER:
+	case MLX5_CMD_OP_QUERY_VPORT_STATE:
+	case MLX5_CMD_OP_QUERY_WOL_ROL:
+	case MLX5_CMD_OP_QUERY_XRC_SRQ:
+	case MLX5_CMD_OP_QUERY_XRQ_DC_PARAMS_ENTRY:
+	case MLX5_CMD_OP_QUERY_XRQ_ERROR_PARAMS:
+	case MLX5_CMD_OP_QUERY_XRQ:
+	case MLX5_CMD_OP_USER_QUERY_XRQ_DC_PARAMS_ENTRY:
+	case MLX5_CMD_OP_USER_QUERY_XRQ_ERROR_PARAMS:
+		return scope >= FWCTL_RPC_DEBUG_READ_ONLY;
+
+	case MLX5_CMD_OP_SET_DIAGNOSTIC_PARAMS:
+		return scope >= FWCTL_RPC_DEBUG_WRITE;
+
+	case MLX5_CMD_OP_ACCESS_REG:
+	case MLX5_CMD_OP_ACCESS_REGISTER_USER:
+		if (op_mod == 0) /* write */
+			return true; /* scope >= FWCTL_RPC_CONFIGURATION; */
+		return scope >= FWCTL_RPC_DEBUG_READ_ONLY;
+	default:
+		return false;
+	}
+}
+
+static void *mlx5ctl_fw_rpc(struct fwctl_uctx *uctx, enum fwctl_rpc_scope scope,
+			    void *rpc_in, size_t in_len, size_t *out_len)
+{
+	struct mlx5ctl_dev *mcdev =
+		container_of(uctx->fwctl, struct mlx5ctl_dev, fwctl);
+	struct mlx5ctl_uctx *mfd =
+		container_of(uctx, struct mlx5ctl_uctx, uctx);
+	void *rpc_out;
+	int ret;
+
+	if (in_len < MLX5_ST_SZ_BYTES(mbox_in_hdr) ||
+	    *out_len < MLX5_ST_SZ_BYTES(mbox_out_hdr))
+		return ERR_PTR(-EMSGSIZE);
+
+	mlx5ctl_dbg(mcdev, "[UID %d] cmdif: opcode 0x%x inlen %zu outlen %zu\n",
+		    mfd->uctx_uid, MLX5_GET(mbox_in_hdr, rpc_in, opcode),
+		    in_len, *out_len);
+
+	if (!mlx5ctl_validate_rpc(rpc_in, scope))
+		return ERR_PTR(-EBADMSG);
+
+	/*
+	 * mlx5_cmd_do() copies the input message to its own buffer before
+	 * executing it, so we can reuse the allocation for the output.
+	 */
+	if (*out_len <= in_len) {
+		rpc_out = rpc_in;
+	} else {
+		rpc_out = kvzalloc(*out_len, GFP_KERNEL);
+		if (!rpc_out)
+			return ERR_PTR(-ENOMEM);
+	}
+
+	/* Enforce the user context for the command */
+	MLX5_SET(mbox_in_hdr, rpc_in, uid, mfd->uctx_uid);
+	ret = mlx5_cmd_do(mcdev->mdev, rpc_in, in_len, rpc_out, *out_len);
+
+	mlx5ctl_dbg(mcdev,
+		    "[UID %d] cmdif: opcode 0x%x status 0x%x retval %pe\n",
+		    mfd->uctx_uid, MLX5_GET(mbox_in_hdr, rpc_in, opcode),
+		    MLX5_GET(mbox_out_hdr, rpc_out, status), ERR_PTR(ret));
+
+	/*
+	 * -EREMOTEIO means execution succeeded and the out is valid,
+	 * but an error code was returned inside out. Everything else
+	 * means the RPC did not make it to the device.
+	 */
+	if (ret && ret != -EREMOTEIO) {
+		if (rpc_out != rpc_in)
+			kfree(rpc_out);
+		return ERR_PTR(ret);
+	}
+	return rpc_out;
+}
+
+static const struct fwctl_ops mlx5ctl_ops = {
+	.device_type = FWCTL_DEVICE_TYPE_MLX5,
+	.uctx_size = sizeof(struct mlx5ctl_uctx),
+	.open_uctx = mlx5ctl_open_uctx,
+	.close_uctx = mlx5ctl_close_uctx,
+	.info = mlx5ctl_info,
+	.fw_rpc = mlx5ctl_fw_rpc,
+};
+
+static int mlx5ctl_probe(struct auxiliary_device *adev,
+			 const struct auxiliary_device_id *id)
+
+{
+	struct mlx5_adev *madev = container_of(adev, struct mlx5_adev, adev);
+	struct mlx5_core_dev *mdev = madev->mdev;
+	struct mlx5ctl_dev *mcdev __free(mlx5ctl) = fwctl_alloc_device(
+		&mdev->pdev->dev, &mlx5ctl_ops, struct mlx5ctl_dev, fwctl);
+	int ret;
+
+	if (!mcdev)
+		return -ENOMEM;
+
+	mcdev->mdev = mdev;
+
+	ret = fwctl_register(&mcdev->fwctl);
+	if (ret)
+		return ret;
+	auxiliary_set_drvdata(adev, no_free_ptr(mcdev));
+	return 0;
+}
+
+static void mlx5ctl_remove(struct auxiliary_device *adev)
+{
+	struct mlx5ctl_dev *mcdev = auxiliary_get_drvdata(adev);
+
+	fwctl_unregister(&mcdev->fwctl);
+	fwctl_put(&mcdev->fwctl);
+}
+
+static const struct auxiliary_device_id mlx5ctl_id_table[] = {
+	{.name = MLX5_ADEV_NAME ".fwctl",},
+	{}
+};
+MODULE_DEVICE_TABLE(auxiliary, mlx5ctl_id_table);
+
+static struct auxiliary_driver mlx5ctl_driver = {
+	.name = "mlx5_fwctl",
+	.probe = mlx5ctl_probe,
+	.remove = mlx5ctl_remove,
+	.id_table = mlx5ctl_id_table,
+};
+
+module_auxiliary_driver(mlx5ctl_driver);
+
+MODULE_IMPORT_NS("FWCTL");
+MODULE_DESCRIPTION("mlx5 ConnectX fwctl driver");
+MODULE_AUTHOR("Saeed Mahameed <saeedm@nvidia.com>");
+MODULE_LICENSE("Dual BSD/GPL");
diff --git a/drivers/fwctl/pds/Makefile b/drivers/fwctl/pds/Makefile
new file mode 100644
index 0000000..cc2317c
--- /dev/null
+++ b/drivers/fwctl/pds/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_FWCTL_PDS) += pds_fwctl.o
+
+pds_fwctl-y += main.o
diff --git a/drivers/fwctl/pds/main.c b/drivers/fwctl/pds/main.c
new file mode 100644
index 0000000..284c416
--- /dev/null
+++ b/drivers/fwctl/pds/main.c
@@ -0,0 +1,536 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) Advanced Micro Devices, Inc */
+
+#include <linux/module.h>
+#include <linux/auxiliary_bus.h>
+#include <linux/pci.h>
+#include <linux/vmalloc.h>
+#include <linux/bitfield.h>
+
+#include <uapi/fwctl/fwctl.h>
+#include <uapi/fwctl/pds.h>
+#include <linux/fwctl.h>
+
+#include <linux/pds/pds_common.h>
+#include <linux/pds/pds_core_if.h>
+#include <linux/pds/pds_adminq.h>
+#include <linux/pds/pds_auxbus.h>
+
+struct pdsfc_uctx {
+	struct fwctl_uctx uctx;
+	u32 uctx_caps;
+};
+
+struct pdsfc_rpc_endpoint_info {
+	u32 endpoint;
+	dma_addr_t operations_pa;
+	struct pds_fwctl_query_data *operations;
+	struct mutex lock;	/* lock for endpoint info management */
+};
+
+struct pdsfc_dev {
+	struct fwctl_device fwctl;
+	struct pds_auxiliary_dev *padev;
+	u32 caps;
+	struct pds_fwctl_ident ident;
+	dma_addr_t endpoints_pa;
+	struct pds_fwctl_query_data *endpoints;
+	struct pdsfc_rpc_endpoint_info *endpoint_info;
+};
+
+static int pdsfc_open_uctx(struct fwctl_uctx *uctx)
+{
+	struct pdsfc_dev *pdsfc = container_of(uctx->fwctl, struct pdsfc_dev, fwctl);
+	struct pdsfc_uctx *pdsfc_uctx = container_of(uctx, struct pdsfc_uctx, uctx);
+
+	pdsfc_uctx->uctx_caps = pdsfc->caps;
+
+	return 0;
+}
+
+static void pdsfc_close_uctx(struct fwctl_uctx *uctx)
+{
+}
+
+static void *pdsfc_info(struct fwctl_uctx *uctx, size_t *length)
+{
+	struct pdsfc_uctx *pdsfc_uctx = container_of(uctx, struct pdsfc_uctx, uctx);
+	struct fwctl_info_pds *info;
+
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return ERR_PTR(-ENOMEM);
+
+	info->uctx_caps = pdsfc_uctx->uctx_caps;
+
+	return info;
+}
+
+static int pdsfc_identify(struct pdsfc_dev *pdsfc)
+{
+	struct device *dev = &pdsfc->fwctl.dev;
+	union pds_core_adminq_comp comp = {0};
+	union pds_core_adminq_cmd cmd;
+	struct pds_fwctl_ident *ident;
+	dma_addr_t ident_pa;
+	int err;
+
+	ident = dma_alloc_coherent(dev->parent, sizeof(*ident), &ident_pa, GFP_KERNEL);
+	if (!ident) {
+		dev_err(dev, "Failed to map ident buffer\n");
+		return -ENOMEM;
+	}
+
+	cmd = (union pds_core_adminq_cmd) {
+		.fwctl_ident = {
+			.opcode = PDS_FWCTL_CMD_IDENT,
+			.version = 0,
+			.len = cpu_to_le32(sizeof(*ident)),
+			.ident_pa = cpu_to_le64(ident_pa),
+		}
+	};
+
+	err = pds_client_adminq_cmd(pdsfc->padev, &cmd, sizeof(cmd), &comp, 0);
+	if (err)
+		dev_err(dev, "Failed to send adminq cmd opcode: %u err: %d\n",
+			cmd.fwctl_ident.opcode, err);
+	else
+		pdsfc->ident = *ident;
+
+	dma_free_coherent(dev->parent, sizeof(*ident), ident, ident_pa);
+
+	return err;
+}
+
+static void pdsfc_free_endpoints(struct pdsfc_dev *pdsfc)
+{
+	struct device *dev = &pdsfc->fwctl.dev;
+	int i;
+
+	if (!pdsfc->endpoints)
+		return;
+
+	for (i = 0; pdsfc->endpoint_info && i < pdsfc->endpoints->num_entries; i++)
+		mutex_destroy(&pdsfc->endpoint_info[i].lock);
+	vfree(pdsfc->endpoint_info);
+	pdsfc->endpoint_info = NULL;
+	dma_free_coherent(dev->parent, PAGE_SIZE,
+			  pdsfc->endpoints, pdsfc->endpoints_pa);
+	pdsfc->endpoints = NULL;
+	pdsfc->endpoints_pa = DMA_MAPPING_ERROR;
+}
+
+static void pdsfc_free_operations(struct pdsfc_dev *pdsfc)
+{
+	struct device *dev = &pdsfc->fwctl.dev;
+	u32 num_endpoints;
+	int i;
+
+	num_endpoints = le32_to_cpu(pdsfc->endpoints->num_entries);
+	for (i = 0; i < num_endpoints; i++) {
+		struct pdsfc_rpc_endpoint_info *ei = &pdsfc->endpoint_info[i];
+
+		if (ei->operations) {
+			dma_free_coherent(dev->parent, PAGE_SIZE,
+					  ei->operations, ei->operations_pa);
+			ei->operations = NULL;
+			ei->operations_pa = DMA_MAPPING_ERROR;
+		}
+	}
+}
+
+static struct pds_fwctl_query_data *pdsfc_get_endpoints(struct pdsfc_dev *pdsfc,
+							dma_addr_t *pa)
+{
+	struct device *dev = &pdsfc->fwctl.dev;
+	union pds_core_adminq_comp comp = {0};
+	struct pds_fwctl_query_data *data;
+	union pds_core_adminq_cmd cmd;
+	dma_addr_t data_pa;
+	int err;
+
+	data = dma_alloc_coherent(dev->parent, PAGE_SIZE, &data_pa, GFP_KERNEL);
+	if (!data) {
+		dev_err(dev, "Failed to map endpoint list\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	cmd = (union pds_core_adminq_cmd) {
+		.fwctl_query = {
+			.opcode = PDS_FWCTL_CMD_QUERY,
+			.entity = PDS_FWCTL_RPC_ROOT,
+			.version = 0,
+			.query_data_buf_len = cpu_to_le32(PAGE_SIZE),
+			.query_data_buf_pa = cpu_to_le64(data_pa),
+		}
+	};
+
+	err = pds_client_adminq_cmd(pdsfc->padev, &cmd, sizeof(cmd), &comp, 0);
+	if (err) {
+		dev_err(dev, "Failed to send adminq cmd opcode: %u entity: %u err: %d\n",
+			cmd.fwctl_query.opcode, cmd.fwctl_query.entity, err);
+		dma_free_coherent(dev->parent, PAGE_SIZE, data, data_pa);
+		return ERR_PTR(err);
+	}
+
+	*pa = data_pa;
+
+	return data;
+}
+
+static int pdsfc_init_endpoints(struct pdsfc_dev *pdsfc)
+{
+	struct pds_fwctl_query_data_endpoint *ep_entry;
+	u32 num_endpoints;
+	int i;
+
+	pdsfc->endpoints = pdsfc_get_endpoints(pdsfc, &pdsfc->endpoints_pa);
+	if (IS_ERR(pdsfc->endpoints))
+		return PTR_ERR(pdsfc->endpoints);
+
+	num_endpoints = le32_to_cpu(pdsfc->endpoints->num_entries);
+	pdsfc->endpoint_info = vcalloc(num_endpoints,
+				       sizeof(*pdsfc->endpoint_info));
+	if (!pdsfc->endpoint_info) {
+		pdsfc_free_endpoints(pdsfc);
+		return -ENOMEM;
+	}
+
+	ep_entry = (struct pds_fwctl_query_data_endpoint *)pdsfc->endpoints->entries;
+	for (i = 0; i < num_endpoints; i++) {
+		mutex_init(&pdsfc->endpoint_info[i].lock);
+		pdsfc->endpoint_info[i].endpoint = ep_entry[i].id;
+	}
+
+	return 0;
+}
+
+static struct pds_fwctl_query_data *pdsfc_get_operations(struct pdsfc_dev *pdsfc,
+							 dma_addr_t *pa, u32 ep)
+{
+	struct pds_fwctl_query_data_operation *entries;
+	struct device *dev = &pdsfc->fwctl.dev;
+	union pds_core_adminq_comp comp = {0};
+	struct pds_fwctl_query_data *data;
+	union pds_core_adminq_cmd cmd;
+	dma_addr_t data_pa;
+	int err;
+	int i;
+
+	/* Query the operations list for the given endpoint */
+	data = dma_alloc_coherent(dev->parent, PAGE_SIZE, &data_pa, GFP_KERNEL);
+	if (!data) {
+		dev_err(dev, "Failed to map operations list\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	cmd = (union pds_core_adminq_cmd) {
+		.fwctl_query = {
+			.opcode = PDS_FWCTL_CMD_QUERY,
+			.entity = PDS_FWCTL_RPC_ENDPOINT,
+			.version = 0,
+			.query_data_buf_len = cpu_to_le32(PAGE_SIZE),
+			.query_data_buf_pa = cpu_to_le64(data_pa),
+			.ep = cpu_to_le32(ep),
+		}
+	};
+
+	err = pds_client_adminq_cmd(pdsfc->padev, &cmd, sizeof(cmd), &comp, 0);
+	if (err) {
+		dev_err(dev, "Failed to send adminq cmd opcode: %u entity: %u err: %d\n",
+			cmd.fwctl_query.opcode, cmd.fwctl_query.entity, err);
+		dma_free_coherent(dev->parent, PAGE_SIZE, data, data_pa);
+		return ERR_PTR(err);
+	}
+
+	*pa = data_pa;
+
+	entries = (struct pds_fwctl_query_data_operation *)data->entries;
+	dev_dbg(dev, "num_entries %d\n", data->num_entries);
+	for (i = 0; i < data->num_entries; i++) {
+
+		/* Translate FW command attribute to fwctl scope */
+		switch (entries[i].scope) {
+		case PDSFC_FW_CMD_ATTR_READ:
+		case PDSFC_FW_CMD_ATTR_WRITE:
+		case PDSFC_FW_CMD_ATTR_SYNC:
+			entries[i].scope = FWCTL_RPC_CONFIGURATION;
+			break;
+		case PDSFC_FW_CMD_ATTR_DEBUG_READ:
+			entries[i].scope = FWCTL_RPC_DEBUG_READ_ONLY;
+			break;
+		case PDSFC_FW_CMD_ATTR_DEBUG_WRITE:
+			entries[i].scope = FWCTL_RPC_DEBUG_WRITE;
+			break;
+		default:
+			entries[i].scope = FWCTL_RPC_DEBUG_WRITE_FULL;
+			break;
+		}
+		dev_dbg(dev, "endpoint %d operation: id %x scope %d\n",
+			ep, entries[i].id, entries[i].scope);
+	}
+
+	return data;
+}
+
+static int pdsfc_validate_rpc(struct pdsfc_dev *pdsfc,
+			      struct fwctl_rpc_pds *rpc,
+			      enum fwctl_rpc_scope scope)
+{
+	struct pds_fwctl_query_data_operation *op_entry;
+	struct pdsfc_rpc_endpoint_info *ep_info = NULL;
+	struct device *dev = &pdsfc->fwctl.dev;
+	int i;
+
+	/* validate rpc in_len & out_len based
+	 * on ident.max_req_sz & max_resp_sz
+	 */
+	if (rpc->in.len > pdsfc->ident.max_req_sz) {
+		dev_dbg(dev, "Invalid request size %u, max %u\n",
+			rpc->in.len, pdsfc->ident.max_req_sz);
+		return -EINVAL;
+	}
+
+	if (rpc->out.len > pdsfc->ident.max_resp_sz) {
+		dev_dbg(dev, "Invalid response size %u, max %u\n",
+			rpc->out.len, pdsfc->ident.max_resp_sz);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < pdsfc->endpoints->num_entries; i++) {
+		if (pdsfc->endpoint_info[i].endpoint == rpc->in.ep) {
+			ep_info = &pdsfc->endpoint_info[i];
+			break;
+		}
+	}
+	if (!ep_info) {
+		dev_dbg(dev, "Invalid endpoint %d\n", rpc->in.ep);
+		return -EINVAL;
+	}
+
+	/* query and cache this endpoint's operations */
+	mutex_lock(&ep_info->lock);
+	if (!ep_info->operations) {
+		struct pds_fwctl_query_data *operations;
+
+		operations = pdsfc_get_operations(pdsfc,
+						  &ep_info->operations_pa,
+						  rpc->in.ep);
+		if (IS_ERR(operations)) {
+			mutex_unlock(&ep_info->lock);
+			return -ENOMEM;
+		}
+		ep_info->operations = operations;
+	}
+	mutex_unlock(&ep_info->lock);
+
+	/* reject unsupported and/or out of scope commands */
+	op_entry = (struct pds_fwctl_query_data_operation *)ep_info->operations->entries;
+	for (i = 0; i < ep_info->operations->num_entries; i++) {
+		if (PDS_FWCTL_RPC_OPCODE_CMP(rpc->in.op, op_entry[i].id)) {
+			if (scope < op_entry[i].scope)
+				return -EPERM;
+			return 0;
+		}
+	}
+
+	dev_dbg(dev, "Invalid operation %d for endpoint %d\n", rpc->in.op, rpc->in.ep);
+
+	return -EINVAL;
+}
+
+static void *pdsfc_fw_rpc(struct fwctl_uctx *uctx, enum fwctl_rpc_scope scope,
+			  void *in, size_t in_len, size_t *out_len)
+{
+	struct pdsfc_dev *pdsfc = container_of(uctx->fwctl, struct pdsfc_dev, fwctl);
+	struct device *dev = &uctx->fwctl->dev;
+	union pds_core_adminq_comp comp = {0};
+	dma_addr_t out_payload_dma_addr = 0;
+	dma_addr_t in_payload_dma_addr = 0;
+	struct fwctl_rpc_pds *rpc = in;
+	union pds_core_adminq_cmd cmd;
+	void *out_payload = NULL;
+	void *in_payload = NULL;
+	void *out = NULL;
+	int err;
+
+	err = pdsfc_validate_rpc(pdsfc, rpc, scope);
+	if (err)
+		return ERR_PTR(err);
+
+	if (rpc->in.len > 0) {
+		in_payload = kzalloc(rpc->in.len, GFP_KERNEL);
+		if (!in_payload) {
+			dev_err(dev, "Failed to allocate in_payload\n");
+			err = -ENOMEM;
+			goto err_out;
+		}
+
+		if (copy_from_user(in_payload, u64_to_user_ptr(rpc->in.payload),
+				   rpc->in.len)) {
+			dev_dbg(dev, "Failed to copy in_payload from user\n");
+			err = -EFAULT;
+			goto err_in_payload;
+		}
+
+		in_payload_dma_addr = dma_map_single(dev->parent, in_payload,
+						     rpc->in.len, DMA_TO_DEVICE);
+		err = dma_mapping_error(dev->parent, in_payload_dma_addr);
+		if (err) {
+			dev_dbg(dev, "Failed to map in_payload\n");
+			goto err_in_payload;
+		}
+	}
+
+	if (rpc->out.len > 0) {
+		out_payload = kzalloc(rpc->out.len, GFP_KERNEL);
+		if (!out_payload) {
+			dev_dbg(dev, "Failed to allocate out_payload\n");
+			err = -ENOMEM;
+			goto err_out_payload;
+		}
+
+		out_payload_dma_addr = dma_map_single(dev->parent, out_payload,
+						      rpc->out.len, DMA_FROM_DEVICE);
+		err = dma_mapping_error(dev->parent, out_payload_dma_addr);
+		if (err) {
+			dev_dbg(dev, "Failed to map out_payload\n");
+			goto err_out_payload;
+		}
+	}
+
+	cmd = (union pds_core_adminq_cmd) {
+		.fwctl_rpc = {
+			.opcode = PDS_FWCTL_CMD_RPC,
+			.flags = PDS_FWCTL_RPC_IND_REQ | PDS_FWCTL_RPC_IND_RESP,
+			.ep = cpu_to_le32(rpc->in.ep),
+			.op = cpu_to_le32(rpc->in.op),
+			.req_pa = cpu_to_le64(in_payload_dma_addr),
+			.req_sz = cpu_to_le32(rpc->in.len),
+			.resp_pa = cpu_to_le64(out_payload_dma_addr),
+			.resp_sz = cpu_to_le32(rpc->out.len),
+		}
+	};
+
+	err = pds_client_adminq_cmd(pdsfc->padev, &cmd, sizeof(cmd), &comp, 0);
+	if (err) {
+		dev_dbg(dev, "%s: ep %d op %x req_pa %llx req_sz %d req_sg %d resp_pa %llx resp_sz %d resp_sg %d err %d\n",
+			__func__, rpc->in.ep, rpc->in.op,
+			cmd.fwctl_rpc.req_pa, cmd.fwctl_rpc.req_sz, cmd.fwctl_rpc.req_sg_elems,
+			cmd.fwctl_rpc.resp_pa, cmd.fwctl_rpc.resp_sz, cmd.fwctl_rpc.resp_sg_elems,
+			err);
+		goto done;
+	}
+
+	dynamic_hex_dump("out ", DUMP_PREFIX_OFFSET, 16, 1, out_payload, rpc->out.len, true);
+
+	if (copy_to_user(u64_to_user_ptr(rpc->out.payload), out_payload, rpc->out.len)) {
+		dev_dbg(dev, "Failed to copy out_payload to user\n");
+		out = ERR_PTR(-EFAULT);
+		goto done;
+	}
+
+	rpc->out.retval = le32_to_cpu(comp.fwctl_rpc.err);
+	*out_len = in_len;
+	out = in;
+
+done:
+	if (out_payload_dma_addr)
+		dma_unmap_single(dev->parent, out_payload_dma_addr,
+				 rpc->out.len, DMA_FROM_DEVICE);
+err_out_payload:
+	kfree(out_payload);
+
+	if (in_payload_dma_addr)
+		dma_unmap_single(dev->parent, in_payload_dma_addr,
+				 rpc->in.len, DMA_TO_DEVICE);
+err_in_payload:
+	kfree(in_payload);
+err_out:
+	if (err)
+		return ERR_PTR(err);
+
+	return out;
+}
+
+static const struct fwctl_ops pdsfc_ops = {
+	.device_type = FWCTL_DEVICE_TYPE_PDS,
+	.uctx_size = sizeof(struct pdsfc_uctx),
+	.open_uctx = pdsfc_open_uctx,
+	.close_uctx = pdsfc_close_uctx,
+	.info = pdsfc_info,
+	.fw_rpc = pdsfc_fw_rpc,
+};
+
+static int pdsfc_probe(struct auxiliary_device *adev,
+		       const struct auxiliary_device_id *id)
+{
+	struct pds_auxiliary_dev *padev =
+			container_of(adev, struct pds_auxiliary_dev, aux_dev);
+	struct device *dev = &adev->dev;
+	struct pdsfc_dev *pdsfc;
+	int err;
+
+	pdsfc = fwctl_alloc_device(&padev->vf_pdev->dev, &pdsfc_ops,
+				   struct pdsfc_dev, fwctl);
+	if (!pdsfc)
+		return dev_err_probe(dev, -ENOMEM, "Failed to allocate fwctl device struct\n");
+	pdsfc->padev = padev;
+
+	err = pdsfc_identify(pdsfc);
+	if (err) {
+		fwctl_put(&pdsfc->fwctl);
+		return dev_err_probe(dev, err, "Failed to identify device\n");
+	}
+
+	err = pdsfc_init_endpoints(pdsfc);
+	if (err) {
+		fwctl_put(&pdsfc->fwctl);
+		return dev_err_probe(dev, err, "Failed to init endpoints\n");
+	}
+
+	pdsfc->caps = PDS_FWCTL_QUERY_CAP | PDS_FWCTL_SEND_CAP;
+
+	err = fwctl_register(&pdsfc->fwctl);
+	if (err) {
+		pdsfc_free_endpoints(pdsfc);
+		fwctl_put(&pdsfc->fwctl);
+		return dev_err_probe(dev, err, "Failed to register device\n");
+	}
+
+	auxiliary_set_drvdata(adev, pdsfc);
+
+	return 0;
+}
+
+static void pdsfc_remove(struct auxiliary_device *adev)
+{
+	struct pdsfc_dev *pdsfc = auxiliary_get_drvdata(adev);
+
+	fwctl_unregister(&pdsfc->fwctl);
+	pdsfc_free_operations(pdsfc);
+	pdsfc_free_endpoints(pdsfc);
+
+	fwctl_put(&pdsfc->fwctl);
+}
+
+static const struct auxiliary_device_id pdsfc_id_table[] = {
+	{.name = PDS_CORE_DRV_NAME "." PDS_DEV_TYPE_FWCTL_STR },
+	{}
+};
+MODULE_DEVICE_TABLE(auxiliary, pdsfc_id_table);
+
+static struct auxiliary_driver pdsfc_driver = {
+	.name = "pds_fwctl",
+	.probe = pdsfc_probe,
+	.remove = pdsfc_remove,
+	.id_table = pdsfc_id_table,
+};
+
+module_auxiliary_driver(pdsfc_driver);
+
+MODULE_IMPORT_NS("FWCTL");
+MODULE_DESCRIPTION("pds fwctl driver");
+MODULE_AUTHOR("Shannon Nelson <shannon.nelson@amd.com>");
+MODULE_AUTHOR("Brett Creeley <brett.creeley@amd.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/ethernet/amd/pds_core/auxbus.c b/drivers/net/ethernet/amd/pds_core/auxbus.c
index 2babea1..eeb72b1 100644
--- a/drivers/net/ethernet/amd/pds_core/auxbus.c
+++ b/drivers/net/ethernet/amd/pds_core/auxbus.c
@@ -175,34 +175,32 @@ static struct pds_auxiliary_dev *pdsc_auxbus_dev_register(struct pdsc *cf,
 	return padev;
 }
 
-int pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf)
+void pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf,
+			 struct pds_auxiliary_dev **pd_ptr)
 {
 	struct pds_auxiliary_dev *padev;
-	int err = 0;
 
-	if (!cf)
-		return -ENODEV;
+	if (!*pd_ptr)
+		return;
 
 	mutex_lock(&pf->config_lock);
 
-	padev = pf->vfs[cf->vf_id].padev;
-	if (padev) {
-		pds_client_unregister(pf, padev->client_id);
-		auxiliary_device_delete(&padev->aux_dev);
-		auxiliary_device_uninit(&padev->aux_dev);
-		padev->client_id = 0;
-	}
-	pf->vfs[cf->vf_id].padev = NULL;
+	padev = *pd_ptr;
+	pds_client_unregister(pf, padev->client_id);
+	auxiliary_device_delete(&padev->aux_dev);
+	auxiliary_device_uninit(&padev->aux_dev);
+	padev->client_id = 0;
+	*pd_ptr = NULL;
 
 	mutex_unlock(&pf->config_lock);
-	return err;
 }
 
-int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
+int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf,
+			enum pds_core_vif_types vt,
+			struct pds_auxiliary_dev **pd_ptr)
 {
 	struct pds_auxiliary_dev *padev;
 	char devname[PDS_DEVNAME_LEN];
-	enum pds_core_vif_types vt;
 	unsigned long mask;
 	u16 vt_support;
 	int client_id;
@@ -211,6 +209,9 @@ int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
 	if (!cf)
 		return -ENODEV;
 
+	if (vt >= PDS_DEV_TYPE_MAX)
+		return -EINVAL;
+
 	mutex_lock(&pf->config_lock);
 
 	mask = BIT_ULL(PDSC_S_FW_DEAD) |
@@ -222,17 +223,10 @@ int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
 		goto out_unlock;
 	}
 
-	/* We only support vDPA so far, so it is the only one to
-	 * be verified that it is available in the Core device and
-	 * enabled in the devlink param.  In the future this might
-	 * become a loop for several VIF types.
-	 */
-
 	/* Verify that the type is supported and enabled.  It is not
-	 * an error if there is no auxbus device support for this
-	 * VF, it just means something else needs to happen with it.
+	 * an error if the firmware doesn't support the feature, the
+	 * driver just won't set up an auxiliary_device for it.
 	 */
-	vt = PDS_DEV_TYPE_VDPA;
 	vt_support = !!le16_to_cpu(pf->dev_ident.vif_types[vt]);
 	if (!(vt_support &&
 	      pf->viftype_status[vt].supported &&
@@ -258,7 +252,7 @@ int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
 		err = PTR_ERR(padev);
 		goto out_unlock;
 	}
-	pf->vfs[cf->vf_id].padev = padev;
+	*pd_ptr = padev;
 
 out_unlock:
 	mutex_unlock(&pf->config_lock);
diff --git a/drivers/net/ethernet/amd/pds_core/core.c b/drivers/net/ethernet/amd/pds_core/core.c
index 536635e..1eb0d92 100644
--- a/drivers/net/ethernet/amd/pds_core/core.c
+++ b/drivers/net/ethernet/amd/pds_core/core.c
@@ -402,6 +402,9 @@ err_out_uninit:
 }
 
 static struct pdsc_viftype pdsc_viftype_defaults[] = {
+	[PDS_DEV_TYPE_FWCTL] = { .name = PDS_DEV_TYPE_FWCTL_STR,
+				 .vif_id = PDS_DEV_TYPE_FWCTL,
+				 .dl_id = -1 },
 	[PDS_DEV_TYPE_VDPA] = { .name = PDS_DEV_TYPE_VDPA_STR,
 				.vif_id = PDS_DEV_TYPE_VDPA,
 				.dl_id = DEVLINK_PARAM_GENERIC_ID_ENABLE_VNET },
@@ -428,6 +431,10 @@ static int pdsc_viftypes_init(struct pdsc *pdsc)
 
 		/* See what the Core device has for support */
 		vt_support = !!le16_to_cpu(pdsc->dev_ident.vif_types[vt]);
+
+		if (vt == PDS_DEV_TYPE_FWCTL)
+			pdsc->viftype_status[vt].enabled = true;
+
 		dev_dbg(pdsc->dev, "VIF %s is %ssupported\n",
 			pdsc->viftype_status[vt].name,
 			vt_support ? "" : "not ");
diff --git a/drivers/net/ethernet/amd/pds_core/core.h b/drivers/net/ethernet/amd/pds_core/core.h
index 14522d6..0bf320c 100644
--- a/drivers/net/ethernet/amd/pds_core/core.h
+++ b/drivers/net/ethernet/amd/pds_core/core.h
@@ -156,6 +156,7 @@ struct pdsc {
 	struct dentry *dentry;
 	struct device *dev;
 	struct pdsc_dev_bar bars[PDS_CORE_BARS_MAX];
+	struct pds_auxiliary_dev *padev;
 	struct pdsc_vf *vfs;
 	int num_vfs;
 	int vf_id;
@@ -303,8 +304,11 @@ void pdsc_health_thread(struct work_struct *work);
 int pdsc_register_notify(struct notifier_block *nb);
 void pdsc_unregister_notify(struct notifier_block *nb);
 void pdsc_notify(unsigned long event, void *data);
-int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf);
-int pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf);
+int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf,
+			enum pds_core_vif_types vt,
+			struct pds_auxiliary_dev **pd_ptr);
+void pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf,
+			 struct pds_auxiliary_dev **pd_ptr);
 
 void pdsc_process_adminq(struct pdsc_qcq *qcq);
 void pdsc_work_thread(struct work_struct *work);
diff --git a/drivers/net/ethernet/amd/pds_core/devlink.c b/drivers/net/ethernet/amd/pds_core/devlink.c
index 44971e7..c5c787d 100644
--- a/drivers/net/ethernet/amd/pds_core/devlink.c
+++ b/drivers/net/ethernet/amd/pds_core/devlink.c
@@ -56,8 +56,11 @@ int pdsc_dl_enable_set(struct devlink *dl, u32 id,
 	for (vf_id = 0; vf_id < pdsc->num_vfs; vf_id++) {
 		struct pdsc *vf = pdsc->vfs[vf_id].vf;
 
-		err = ctx->val.vbool ? pdsc_auxbus_dev_add(vf, pdsc) :
-				       pdsc_auxbus_dev_del(vf, pdsc);
+		if (ctx->val.vbool)
+			err = pdsc_auxbus_dev_add(vf, pdsc, vt_entry->vif_id,
+						  &pdsc->vfs[vf_id].padev);
+		else
+			pdsc_auxbus_dev_del(vf, pdsc, &pdsc->vfs[vf_id].padev);
 	}
 
 	return err;
diff --git a/drivers/net/ethernet/amd/pds_core/main.c b/drivers/net/ethernet/amd/pds_core/main.c
index 660268f..4843f92 100644
--- a/drivers/net/ethernet/amd/pds_core/main.c
+++ b/drivers/net/ethernet/amd/pds_core/main.c
@@ -190,7 +190,8 @@ static int pdsc_init_vf(struct pdsc *vf)
 	devl_unlock(dl);
 
 	pf->vfs[vf->vf_id].vf = vf;
-	err = pdsc_auxbus_dev_add(vf, pf);
+	err = pdsc_auxbus_dev_add(vf, pf, PDS_DEV_TYPE_VDPA,
+				  &pf->vfs[vf->vf_id].padev);
 	if (err) {
 		devl_lock(dl);
 		devl_unregister(dl);
@@ -264,6 +265,10 @@ static int pdsc_init_pf(struct pdsc *pdsc)
 
 	mutex_unlock(&pdsc->config_lock);
 
+	err = pdsc_auxbus_dev_add(pdsc, pdsc, PDS_DEV_TYPE_FWCTL, &pdsc->padev);
+	if (err)
+		goto err_out_stop;
+
 	dl = priv_to_devlink(pdsc);
 	devl_lock(dl);
 	err = devl_params_register(dl, pdsc_dl_params,
@@ -272,7 +277,7 @@ static int pdsc_init_pf(struct pdsc *pdsc)
 		devl_unlock(dl);
 		dev_warn(pdsc->dev, "Failed to register devlink params: %pe\n",
 			 ERR_PTR(err));
-		goto err_out_stop;
+		goto err_out_del_dev;
 	}
 
 	hr = devl_health_reporter_create(dl, &pdsc_fw_reporter_ops, 0, pdsc);
@@ -295,6 +300,8 @@ static int pdsc_init_pf(struct pdsc *pdsc)
 err_out_unreg_params:
 	devlink_params_unregister(dl, pdsc_dl_params,
 				  ARRAY_SIZE(pdsc_dl_params));
+err_out_del_dev:
+	pdsc_auxbus_dev_del(pdsc, pdsc, &pdsc->padev);
 err_out_stop:
 	pdsc_stop(pdsc);
 err_out_teardown:
@@ -417,7 +424,7 @@ static void pdsc_remove(struct pci_dev *pdev)
 
 		pf = pdsc_get_pf_struct(pdsc->pdev);
 		if (!IS_ERR(pf)) {
-			pdsc_auxbus_dev_del(pdsc, pf);
+			pdsc_auxbus_dev_del(pdsc, pf, &pf->vfs[pdsc->vf_id].padev);
 			pf->vfs[pdsc->vf_id].vf = NULL;
 		}
 	} else {
@@ -426,6 +433,7 @@ static void pdsc_remove(struct pci_dev *pdev)
 		 * shut themselves down.
 		 */
 		pdsc_sriov_configure(pdev, 0);
+		pdsc_auxbus_dev_del(pdsc, pdsc, &pdsc->padev);
 
 		timer_shutdown_sync(&pdsc->wdtimer);
 		if (pdsc->wq)
@@ -482,7 +490,10 @@ static void pdsc_reset_prepare(struct pci_dev *pdev)
 
 		pf = pdsc_get_pf_struct(pdsc->pdev);
 		if (!IS_ERR(pf))
-			pdsc_auxbus_dev_del(pdsc, pf);
+			pdsc_auxbus_dev_del(pdsc, pf,
+					    &pf->vfs[pdsc->vf_id].padev);
+	} else {
+		pdsc_auxbus_dev_del(pdsc, pdsc, &pdsc->padev);
 	}
 
 	pdsc_unmap_bars(pdsc);
@@ -527,7 +538,11 @@ static void pdsc_reset_done(struct pci_dev *pdev)
 
 		pf = pdsc_get_pf_struct(pdsc->pdev);
 		if (!IS_ERR(pf))
-			pdsc_auxbus_dev_add(pdsc, pf);
+			pdsc_auxbus_dev_add(pdsc, pf, PDS_DEV_TYPE_VDPA,
+					    &pf->vfs[pdsc->vf_id].padev);
+	} else {
+		pdsc_auxbus_dev_add(pdsc, pdsc, PDS_DEV_TYPE_FWCTL,
+				    &pdsc->padev);
 	}
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
index 9a79674..891bbbb 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/dev.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
@@ -228,8 +228,15 @@ enum {
 	MLX5_INTERFACE_PROTOCOL_VNET,
 
 	MLX5_INTERFACE_PROTOCOL_DPLL,
+	MLX5_INTERFACE_PROTOCOL_FWCTL,
 };
 
+static bool is_fwctl_supported(struct mlx5_core_dev *dev)
+{
+	/* fwctl is most useful on PFs, prevent fwctl on SFs for now */
+	return MLX5_CAP_GEN(dev, uctx_cap) && !mlx5_core_is_sf(dev);
+}
+
 static const struct mlx5_adev_device {
 	const char *suffix;
 	bool (*is_supported)(struct mlx5_core_dev *dev);
@@ -252,6 +259,8 @@ static const struct mlx5_adev_device {
 					   .is_supported = &is_mp_supported },
 	[MLX5_INTERFACE_PROTOCOL_DPLL] = { .suffix = "dpll",
 					   .is_supported = &is_dpll_supported },
+	[MLX5_INTERFACE_PROTOCOL_FWCTL] = { .suffix = "fwctl",
+					    .is_supported = &is_fwctl_supported },
 };
 
 int mlx5_adev_idx_alloc(void)
diff --git a/include/cxl/features.h b/include/cxl/features.h
new file mode 100644
index 0000000..a3bb346
--- /dev/null
+++ b/include/cxl/features.h
@@ -0,0 +1,87 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright(c) 2024-2025 Intel Corporation. */
+#ifndef __CXL_FEATURES_H__
+#define __CXL_FEATURES_H__
+
+#include <linux/uuid.h>
+#include <linux/fwctl.h>
+#include <uapi/cxl/features.h>
+
+/* Feature UUIDs used by the kernel */
+#define CXL_FEAT_PATROL_SCRUB_UUID						\
+	UUID_INIT(0x96dad7d6, 0xfde8, 0x482b, 0xa7, 0x33, 0x75, 0x77, 0x4e,	\
+		  0x06, 0xdb, 0x8a)
+
+#define CXL_FEAT_ECS_UUID							\
+	UUID_INIT(0xe5b13f22, 0x2328, 0x4a14, 0xb8, 0xba, 0xb9, 0x69, 0x1e,	\
+		  0x89, 0x33, 0x86)
+
+#define CXL_FEAT_SPPR_UUID							\
+	UUID_INIT(0x892ba475, 0xfad8, 0x474e, 0x9d, 0x3e, 0x69, 0x2c, 0x91,	\
+		  0x75, 0x68, 0xbb)
+
+#define CXL_FEAT_HPPR_UUID							\
+	UUID_INIT(0x80ea4521, 0x786f, 0x4127, 0xaf, 0xb1, 0xec, 0x74, 0x59,	\
+		  0xfb, 0x0e, 0x24)
+
+#define CXL_FEAT_CACHELINE_SPARING_UUID						\
+	UUID_INIT(0x96C33386, 0x91dd, 0x44c7, 0x9e, 0xcb, 0xfd, 0xaf, 0x65,	\
+		  0x03, 0xba, 0xc4)
+
+#define CXL_FEAT_ROW_SPARING_UUID						\
+	UUID_INIT(0x450ebf67, 0xb135, 0x4f97, 0xa4, 0x98, 0xc2, 0xd5, 0x7f,	\
+		  0x27, 0x9b, 0xed)
+
+#define CXL_FEAT_BANK_SPARING_UUID						\
+	UUID_INIT(0x78b79636, 0x90ac, 0x4b64, 0xa4, 0xef, 0xfa, 0xac, 0x5d,	\
+		  0x18, 0xa8, 0x63)
+
+#define CXL_FEAT_RANK_SPARING_UUID						\
+	UUID_INIT(0x34dbaff5, 0x0552, 0x4281, 0x8f, 0x76, 0xda, 0x0b, 0x5e,	\
+		  0x7a, 0x76, 0xa7)
+
+/* Feature commands capability supported by a device */
+enum cxl_features_capability {
+	CXL_FEATURES_NONE = 0,
+	CXL_FEATURES_RO,
+	CXL_FEATURES_RW,
+};
+
+/**
+ * struct cxl_features_state - The Features state for the device
+ * @cxlds: Pointer to CXL device state
+ * @entries: CXl feature entry context
+ */
+struct cxl_features_state {
+	struct cxl_dev_state *cxlds;
+	struct cxl_feat_entries {
+		int num_features;
+		int num_user_features;
+		struct cxl_feat_entry ent[] __counted_by(num_features);
+	} *entries;
+};
+
+struct cxl_mailbox;
+struct cxl_memdev;
+#ifdef CONFIG_CXL_FEATURES
+inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds);
+int devm_cxl_setup_features(struct cxl_dev_state *cxlds);
+int devm_cxl_setup_fwctl(struct cxl_memdev *cxlmd);
+#else
+static inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds)
+{
+	return NULL;
+}
+
+static inline int devm_cxl_setup_features(struct cxl_dev_state *cxlds)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int devm_cxl_setup_fwctl(struct cxl_memdev *cxlmd)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
+#endif
diff --git a/include/cxl/mailbox.h b/include/cxl/mailbox.h
index bacd111..c4e99e2 100644
--- a/include/cxl/mailbox.h
+++ b/include/cxl/mailbox.h
@@ -3,24 +3,66 @@
 #ifndef __CXL_MBOX_H__
 #define __CXL_MBOX_H__
 #include <linux/rcuwait.h>
+#include <cxl/features.h>
+#include <uapi/linux/cxl_mem.h>
 
-struct cxl_mbox_cmd;
+/**
+ * struct cxl_mbox_cmd - A command to be submitted to hardware.
+ * @opcode: (input) The command set and command submitted to hardware.
+ * @payload_in: (input) Pointer to the input payload.
+ * @payload_out: (output) Pointer to the output payload. Must be allocated by
+ *		 the caller.
+ * @size_in: (input) Number of bytes to load from @payload_in.
+ * @size_out: (input) Max number of bytes loaded into @payload_out.
+ *            (output) Number of bytes generated by the device. For fixed size
+ *            outputs commands this is always expected to be deterministic. For
+ *            variable sized output commands, it tells the exact number of bytes
+ *            written.
+ * @min_out: (input) internal command output payload size validation
+ * @poll_count: (input) Number of timeouts to attempt.
+ * @poll_interval_ms: (input) Time between mailbox background command polling
+ *                    interval timeouts.
+ * @return_code: (output) Error code returned from hardware.
+ *
+ * This is the primary mechanism used to send commands to the hardware.
+ * All the fields except @payload_* correspond exactly to the fields described in
+ * Command Register section of the CXL 2.0 8.2.8.4.5. @payload_in and
+ * @payload_out are written to, and read from the Command Payload Registers
+ * defined in CXL 2.0 8.2.8.4.8.
+ */
+struct cxl_mbox_cmd {
+	u16 opcode;
+	void *payload_in;
+	void *payload_out;
+	size_t size_in;
+	size_t size_out;
+	size_t min_out;
+	int poll_count;
+	int poll_interval_ms;
+	u16 return_code;
+};
 
 /**
  * struct cxl_mailbox - context for CXL mailbox operations
  * @host: device that hosts the mailbox
+ * @enabled_cmds: mailbox commands that are enabled by the driver
+ * @exclusive_cmds: mailbox commands that are exclusive to the kernel
  * @payload_size: Size of space for payload
  *                (CXL 3.1 8.2.8.4.3 Mailbox Capabilities Register)
  * @mbox_mutex: mutex protects device mailbox and firmware
  * @mbox_wait: rcuwait for mailbox
  * @mbox_send: @dev specific transport for transmitting mailbox commands
+ * @feat_cap: Features capability
  */
 struct cxl_mailbox {
 	struct device *host;
+	DECLARE_BITMAP(enabled_cmds, CXL_MEM_COMMAND_ID_MAX);
+	DECLARE_BITMAP(exclusive_cmds, CXL_MEM_COMMAND_ID_MAX);
 	size_t payload_size;
 	struct mutex mbox_mutex; /* lock to protect mailbox context */
 	struct rcuwait mbox_wait;
 	int (*mbox_send)(struct cxl_mailbox *cxl_mbox, struct cxl_mbox_cmd *cmd);
+	enum cxl_features_capability feat_cap;
 };
 
 int cxl_mailbox_init(struct cxl_mailbox *cxl_mbox, struct device *host);
diff --git a/include/linux/fwctl.h b/include/linux/fwctl.h
new file mode 100644
index 0000000..5d61fc8
--- /dev/null
+++ b/include/linux/fwctl.h
@@ -0,0 +1,135 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2024-2025, NVIDIA CORPORATION & AFFILIATES
+ */
+#ifndef __LINUX_FWCTL_H
+#define __LINUX_FWCTL_H
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/cleanup.h>
+#include <uapi/fwctl/fwctl.h>
+
+struct fwctl_device;
+struct fwctl_uctx;
+
+/**
+ * struct fwctl_ops - Driver provided operations
+ *
+ * fwctl_unregister() will wait until all excuting ops are completed before it
+ * returns. Drivers should be mindful to not let their ops run for too long as
+ * it will block device hot unplug and module unloading.
+ */
+struct fwctl_ops {
+	/**
+	 * @device_type: The drivers assigned device_type number. This is uABI.
+	 */
+	enum fwctl_device_type device_type;
+	/**
+	 * @uctx_size: The size of the fwctl_uctx struct to allocate. The first
+	 * bytes of this memory will be a fwctl_uctx. The driver can use the
+	 * remaining bytes as its private memory.
+	 */
+	size_t uctx_size;
+	/**
+	 * @open_uctx: Called when a file descriptor is opened before the uctx
+	 * is ever used.
+	 */
+	int (*open_uctx)(struct fwctl_uctx *uctx);
+	/**
+	 * @close_uctx: Called when the uctx is destroyed, usually when the FD
+	 * is closed.
+	 */
+	void (*close_uctx)(struct fwctl_uctx *uctx);
+	/**
+	 * @info: Implement FWCTL_INFO. Return a kmalloc() memory that is copied
+	 * to out_device_data. On input length indicates the size of the user
+	 * buffer on output it indicates the size of the memory. The driver can
+	 * ignore length on input, the core code will handle everything.
+	 */
+	void *(*info)(struct fwctl_uctx *uctx, size_t *length);
+	/**
+	 * @fw_rpc: Implement FWCTL_RPC. Deliver rpc_in/in_len to the FW and
+	 * return the response and set out_len. rpc_in can be returned as the
+	 * response pointer. Otherwise the returned pointer is freed with
+	 * kvfree().
+	 */
+	void *(*fw_rpc)(struct fwctl_uctx *uctx, enum fwctl_rpc_scope scope,
+			void *rpc_in, size_t in_len, size_t *out_len);
+};
+
+/**
+ * struct fwctl_device - Per-driver registration struct
+ * @dev: The sysfs (class/fwctl/fwctlXX) device
+ *
+ * Each driver instance will have one of these structs with the driver private
+ * data following immediately after. This struct is refcounted, it is freed by
+ * calling fwctl_put().
+ */
+struct fwctl_device {
+	struct device dev;
+	/* private: */
+	struct cdev cdev;
+
+	/* Protect uctx_list */
+	struct mutex uctx_list_lock;
+	struct list_head uctx_list;
+	/*
+	 * Protect ops, held for write when ops becomes NULL during unregister,
+	 * held for read whenever ops is loaded or an ops function is running.
+	 */
+	struct rw_semaphore registration_lock;
+	const struct fwctl_ops *ops;
+};
+
+struct fwctl_device *_fwctl_alloc_device(struct device *parent,
+					 const struct fwctl_ops *ops,
+					 size_t size);
+/**
+ * fwctl_alloc_device - Allocate a fwctl
+ * @parent: Physical device that provides the FW interface
+ * @ops: Driver ops to register
+ * @drv_struct: 'struct driver_fwctl' that holds the struct fwctl_device
+ * @member: Name of the struct fwctl_device in @drv_struct
+ *
+ * This allocates and initializes the fwctl_device embedded in the drv_struct.
+ * Upon success the pointer must be freed via fwctl_put(). Returns a 'drv_struct
+ * \*' on success, NULL on error.
+ */
+#define fwctl_alloc_device(parent, ops, drv_struct, member)               \
+	({                                                                \
+		static_assert(__same_type(struct fwctl_device,            \
+					  ((drv_struct *)NULL)->member)); \
+		static_assert(offsetof(drv_struct, member) == 0);         \
+		(drv_struct *)_fwctl_alloc_device(parent, ops,            \
+						  sizeof(drv_struct));    \
+	})
+
+static inline struct fwctl_device *fwctl_get(struct fwctl_device *fwctl)
+{
+	get_device(&fwctl->dev);
+	return fwctl;
+}
+static inline void fwctl_put(struct fwctl_device *fwctl)
+{
+	put_device(&fwctl->dev);
+}
+DEFINE_FREE(fwctl, struct fwctl_device *, if (_T) fwctl_put(_T));
+
+int fwctl_register(struct fwctl_device *fwctl);
+void fwctl_unregister(struct fwctl_device *fwctl);
+
+/**
+ * struct fwctl_uctx - Per user FD context
+ * @fwctl: fwctl instance that owns the context
+ *
+ * Every FD opened by userspace will get a unique context allocation. Any driver
+ * private data will follow immediately after.
+ */
+struct fwctl_uctx {
+	struct fwctl_device *fwctl;
+	/* private: */
+	/* Head at fwctl_device::uctx_list */
+	struct list_head uctx_list_entry;
+};
+
+#endif
diff --git a/include/linux/panic.h b/include/linux/panic.h
index 54d90b6..2494d51 100644
--- a/include/linux/panic.h
+++ b/include/linux/panic.h
@@ -74,7 +74,8 @@ static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
 #define TAINT_AUX			16
 #define TAINT_RANDSTRUCT		17
 #define TAINT_TEST			18
-#define TAINT_FLAGS_COUNT		19
+#define TAINT_FWCTL			19
+#define TAINT_FLAGS_COUNT		20
 #define TAINT_FLAGS_MAX			((1UL << TAINT_FLAGS_COUNT) - 1)
 
 struct taint_flag {
diff --git a/include/linux/pds/pds_adminq.h b/include/linux/pds/pds_adminq.h
index 4b4e9a9..ddd111f 100644
--- a/include/linux/pds/pds_adminq.h
+++ b/include/linux/pds/pds_adminq.h
@@ -1179,6 +1179,274 @@ struct pds_lm_host_vf_status_cmd {
 	u8     status;
 };
 
+enum pds_fwctl_cmd_opcode {
+	PDS_FWCTL_CMD_IDENT = 70,
+	PDS_FWCTL_CMD_RPC   = 71,
+	PDS_FWCTL_CMD_QUERY = 72,
+};
+
+/**
+ * struct pds_fwctl_cmd - Firmware control command structure
+ * @opcode: Opcode
+ * @rsvd:   Reserved
+ * @ep:     Endpoint identifier
+ * @op:     Operation identifier
+ */
+struct pds_fwctl_cmd {
+	u8     opcode;
+	u8     rsvd[3];
+	__le32 ep;
+	__le32 op;
+} __packed;
+
+/**
+ * struct pds_fwctl_comp - Firmware control completion structure
+ * @status:     Status of the firmware control operation
+ * @rsvd:       Reserved
+ * @comp_index: Completion index in little-endian format
+ * @rsvd2:      Reserved
+ * @color:      Color bit indicating the state of the completion
+ */
+struct pds_fwctl_comp {
+	u8     status;
+	u8     rsvd;
+	__le16 comp_index;
+	u8     rsvd2[11];
+	u8     color;
+} __packed;
+
+/**
+ * struct pds_fwctl_ident_cmd - Firmware control identification command structure
+ * @opcode:   Operation code for the command
+ * @rsvd:     Reserved
+ * @version:  Interface version
+ * @rsvd2:    Reserved
+ * @len:      Length of the identification data
+ * @ident_pa: Physical address of the identification data
+ */
+struct pds_fwctl_ident_cmd {
+	u8     opcode;
+	u8     rsvd;
+	u8     version;
+	u8     rsvd2;
+	__le32 len;
+	__le64 ident_pa;
+} __packed;
+
+/* future feature bits here
+ * enum pds_fwctl_features {
+ * };
+ * (compilers don't like empty enums)
+ */
+
+/**
+ * struct pds_fwctl_ident - Firmware control identification structure
+ * @features:    Supported features (enum pds_fwctl_features)
+ * @version:     Interface version
+ * @rsvd:        Reserved
+ * @max_req_sz:  Maximum request size
+ * @max_resp_sz: Maximum response size
+ * @max_req_sg_elems:  Maximum number of request SGs
+ * @max_resp_sg_elems: Maximum number of response SGs
+ */
+struct pds_fwctl_ident {
+	__le64 features;
+	u8     version;
+	u8     rsvd[3];
+	__le32 max_req_sz;
+	__le32 max_resp_sz;
+	u8     max_req_sg_elems;
+	u8     max_resp_sg_elems;
+} __packed;
+
+enum pds_fwctl_query_entity {
+	PDS_FWCTL_RPC_ROOT	= 0,
+	PDS_FWCTL_RPC_ENDPOINT	= 1,
+	PDS_FWCTL_RPC_OPERATION	= 2,
+};
+
+#define PDS_FWCTL_RPC_OPCODE_CMD_SHIFT	0
+#define PDS_FWCTL_RPC_OPCODE_CMD_MASK	GENMASK(15, PDS_FWCTL_RPC_OPCODE_CMD_SHIFT)
+#define PDS_FWCTL_RPC_OPCODE_VER_SHIFT	16
+#define PDS_FWCTL_RPC_OPCODE_VER_MASK	GENMASK(23, PDS_FWCTL_RPC_OPCODE_VER_SHIFT)
+
+#define PDS_FWCTL_RPC_OPCODE_GET_CMD(op)  FIELD_GET(PDS_FWCTL_RPC_OPCODE_CMD_MASK, op)
+#define PDS_FWCTL_RPC_OPCODE_GET_VER(op)  FIELD_GET(PDS_FWCTL_RPC_OPCODE_VER_MASK, op)
+
+#define PDS_FWCTL_RPC_OPCODE_CMP(op1, op2) \
+	(PDS_FWCTL_RPC_OPCODE_GET_CMD(op1) == PDS_FWCTL_RPC_OPCODE_GET_CMD(op2) && \
+	 PDS_FWCTL_RPC_OPCODE_GET_VER(op1) <= PDS_FWCTL_RPC_OPCODE_GET_VER(op2))
+
+/*
+ * FW command attributes that map to the FWCTL scope values
+ */
+#define PDSFC_FW_CMD_ATTR_READ               0x00
+#define PDSFC_FW_CMD_ATTR_DEBUG_READ         0x02
+#define PDSFC_FW_CMD_ATTR_WRITE              0x04
+#define PDSFC_FW_CMD_ATTR_DEBUG_WRITE        0x08
+#define PDSFC_FW_CMD_ATTR_SYNC               0x10
+
+/**
+ * struct pds_fwctl_query_cmd - Firmware control query command structure
+ * @opcode: Operation code for the command
+ * @entity:  Entity type to query (enum pds_fwctl_query_entity)
+ * @version: Version of the query data structure supported by the driver
+ * @rsvd:    Reserved
+ * @query_data_buf_len: Length of the query data buffer
+ * @query_data_buf_pa:  Physical address of the query data buffer
+ * @ep:      Endpoint identifier to query  (when entity is PDS_FWCTL_RPC_ENDPOINT)
+ * @op:      Operation identifier to query (when entity is PDS_FWCTL_RPC_OPERATION)
+ *
+ * This structure is used to send a query command to the firmware control
+ * interface. The structure is packed to ensure there is no padding between
+ * the fields.
+ */
+struct pds_fwctl_query_cmd {
+	u8     opcode;
+	u8     entity;
+	u8     version;
+	u8     rsvd;
+	__le32 query_data_buf_len;
+	__le64 query_data_buf_pa;
+	union {
+		__le32 ep;
+		__le32 op;
+	};
+} __packed;
+
+/**
+ * struct pds_fwctl_query_comp - Firmware control query completion structure
+ * @status:     Status of the query command
+ * @rsvd:       Reserved
+ * @comp_index: Completion index in little-endian format
+ * @version:    Version of the query data structure returned by firmware. This
+ *		 should be less than or equal to the version supported by the driver
+ * @rsvd2:      Reserved
+ * @color:      Color bit indicating the state of the completion
+ */
+struct pds_fwctl_query_comp {
+	u8     status;
+	u8     rsvd;
+	__le16 comp_index;
+	u8     version;
+	u8     rsvd2[2];
+	u8     color;
+} __packed;
+
+/**
+ * struct pds_fwctl_query_data_endpoint - query data for entity PDS_FWCTL_RPC_ROOT
+ * @id: The identifier for the data endpoint
+ */
+struct pds_fwctl_query_data_endpoint {
+	__le32 id;
+} __packed;
+
+/**
+ * struct pds_fwctl_query_data_operation - query data for entity PDS_FWCTL_RPC_ENDPOINT
+ * @id:    Operation identifier
+ * @scope: Scope of the operation (enum fwctl_rpc_scope)
+ * @rsvd:  Reserved
+ */
+struct pds_fwctl_query_data_operation {
+	__le32 id;
+	u8     scope;
+	u8     rsvd[3];
+} __packed;
+
+/**
+ * struct pds_fwctl_query_data - query data structure
+ * @version:     Version of the query data structure
+ * @rsvd:        Reserved
+ * @num_entries: Number of entries in the union
+ * @entries:     Array of query data entries, depending on the entity type
+ */
+struct pds_fwctl_query_data {
+	u8      version;
+	u8      rsvd[3];
+	__le32  num_entries;
+	u8      entries[] __counted_by_le(num_entries);
+} __packed;
+
+/**
+ * struct pds_fwctl_rpc_cmd - Firmware control RPC command
+ * @opcode:        opcode PDS_FWCTL_CMD_RPC
+ * @rsvd:          Reserved
+ * @flags:         Indicates indirect request and/or response handling
+ * @ep:            Endpoint identifier
+ * @op:            Operation identifier
+ * @inline_req0:   Buffer for inline request
+ * @inline_req1:   Buffer for inline request
+ * @req_pa:        Physical address of request data
+ * @req_sz:        Size of the request
+ * @req_sg_elems:  Number of request SGs
+ * @req_rsvd:      Reserved
+ * @inline_req2:   Buffer for inline request
+ * @resp_pa:       Physical address of response data
+ * @resp_sz:       Size of the response
+ * @resp_sg_elems: Number of response SGs
+ * @resp_rsvd:     Reserved
+ */
+struct pds_fwctl_rpc_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 flags;
+#define PDS_FWCTL_RPC_IND_REQ		0x1
+#define PDS_FWCTL_RPC_IND_RESP		0x2
+	__le32 ep;
+	__le32 op;
+	u8 inline_req0[16];
+	union {
+		u8 inline_req1[16];
+		struct {
+			__le64 req_pa;
+			__le32 req_sz;
+			u8     req_sg_elems;
+			u8     req_rsvd[3];
+		};
+	};
+	union {
+		u8 inline_req2[16];
+		struct {
+			__le64 resp_pa;
+			__le32 resp_sz;
+			u8     resp_sg_elems;
+			u8     resp_rsvd[3];
+		};
+	};
+} __packed;
+
+/**
+ * struct pds_sg_elem - Transmit scatter-gather (SG) descriptor element
+ * @addr:	DMA address of SG element data buffer
+ * @len:	Length of SG element data buffer, in bytes
+ * @rsvd:	Reserved
+ */
+struct pds_sg_elem {
+	__le64 addr;
+	__le32 len;
+	u8     rsvd[4];
+} __packed;
+
+/**
+ * struct pds_fwctl_rpc_comp - Completion of a firmware control RPC
+ * @status:     Status of the command
+ * @rsvd:       Reserved
+ * @comp_index: Completion index of the command
+ * @err:        Error code, if any, from the RPC
+ * @resp_sz:    Size of the response
+ * @rsvd2:      Reserved
+ * @color:      Color bit indicating the state of the completion
+ */
+struct pds_fwctl_rpc_comp {
+	u8     status;
+	u8     rsvd;
+	__le16 comp_index;
+	__le32 err;
+	__le32 resp_sz;
+	u8     rsvd2[3];
+	u8     color;
+} __packed;
+
 union pds_core_adminq_cmd {
 	u8     opcode;
 	u8     bytes[64];
@@ -1216,6 +1484,11 @@ union pds_core_adminq_cmd {
 	struct pds_lm_dirty_enable_cmd	  lm_dirty_enable;
 	struct pds_lm_dirty_disable_cmd	  lm_dirty_disable;
 	struct pds_lm_dirty_seq_ack_cmd	  lm_dirty_seq_ack;
+
+	struct pds_fwctl_cmd		  fwctl;
+	struct pds_fwctl_ident_cmd	  fwctl_ident;
+	struct pds_fwctl_rpc_cmd	  fwctl_rpc;
+	struct pds_fwctl_query_cmd	  fwctl_query;
 };
 
 union pds_core_adminq_comp {
@@ -1243,6 +1516,10 @@ union pds_core_adminq_comp {
 
 	struct pds_lm_state_size_comp	  lm_state_size;
 	struct pds_lm_dirty_status_comp	  lm_dirty_status;
+
+	struct pds_fwctl_comp		  fwctl;
+	struct pds_fwctl_rpc_comp	  fwctl_rpc;
+	struct pds_fwctl_query_comp	  fwctl_query;
 };
 
 #ifndef __CHECKER__
diff --git a/include/linux/pds/pds_common.h b/include/linux/pds/pds_common.h
index 5802e1d..b193adb 100644
--- a/include/linux/pds/pds_common.h
+++ b/include/linux/pds/pds_common.h
@@ -29,6 +29,7 @@ enum pds_core_vif_types {
 	PDS_DEV_TYPE_ETH	= 3,
 	PDS_DEV_TYPE_RDMA	= 4,
 	PDS_DEV_TYPE_LM		= 5,
+	PDS_DEV_TYPE_FWCTL	= 6,
 
 	/* new ones added before this line */
 	PDS_DEV_TYPE_MAX	= 16   /* don't change - used in struct size */
@@ -40,6 +41,7 @@ enum pds_core_vif_types {
 #define PDS_DEV_TYPE_ETH_STR	"Eth"
 #define PDS_DEV_TYPE_RDMA_STR	"RDMA"
 #define PDS_DEV_TYPE_LM_STR	"LM"
+#define PDS_DEV_TYPE_FWCTL_STR	"fwctl"
 
 #define PDS_VDPA_DEV_NAME	PDS_CORE_DRV_NAME "." PDS_DEV_TYPE_VDPA_STR
 #define PDS_VFIO_LM_DEV_NAME	PDS_CORE_DRV_NAME "." PDS_DEV_TYPE_LM_STR "." PDS_DEV_TYPE_VFIO_STR
diff --git a/include/uapi/cxl/features.h b/include/uapi/cxl/features.h
new file mode 100644
index 0000000..d6db898
--- /dev/null
+++ b/include/uapi/cxl/features.h
@@ -0,0 +1,170 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2024,2025, Intel Corporation
+ *
+ * These are definitions for the mailbox command interface of CXL subsystem.
+ */
+#ifndef _UAPI_CXL_FEATURES_H_
+#define _UAPI_CXL_FEATURES_H_
+
+#include <linux/types.h>
+#ifndef __KERNEL__
+#include <uuid/uuid.h>
+#else
+#include <linux/uuid.h>
+#endif
+
+/*
+ * struct cxl_mbox_get_sup_feats_in - Get Supported Features input
+ *
+ * @count: bytes of Feature data to return in output
+ * @start_idx: index of first requested Supported Feature Entry, 0 based.
+ * @reserved: reserved field, must be 0s.
+ *
+ * Get Supported Features (0x500h) CXL r3.2 8.2.9.6.1 command.
+ * Input block for Get support Feature
+ */
+struct cxl_mbox_get_sup_feats_in {
+	__le32 count;
+	__le16 start_idx;
+	__u8 reserved[2];
+} __attribute__ ((__packed__));
+
+/* CXL spec r3.2 Table 8-87 command effects */
+#define CXL_CMD_CONFIG_CHANGE_COLD_RESET	BIT(0)
+#define CXL_CMD_CONFIG_CHANGE_IMMEDIATE		BIT(1)
+#define CXL_CMD_DATA_CHANGE_IMMEDIATE		BIT(2)
+#define CXL_CMD_POLICY_CHANGE_IMMEDIATE		BIT(3)
+#define CXL_CMD_LOG_CHANGE_IMMEDIATE		BIT(4)
+#define CXL_CMD_SECURITY_STATE_CHANGE		BIT(5)
+#define CXL_CMD_BACKGROUND			BIT(6)
+#define CXL_CMD_BGCMD_ABORT_SUPPORTED		BIT(7)
+#define CXL_CMD_EFFECTS_VALID			BIT(9)
+#define CXL_CMD_CONFIG_CHANGE_CONV_RESET	BIT(10)
+#define CXL_CMD_CONFIG_CHANGE_CXL_RESET		BIT(11)
+#define CXL_CMD_EFFECTS_RESERVED		GENMASK(15, 12)
+
+/*
+ * struct cxl_feat_entry - Supported Feature Entry
+ * @uuid: UUID of the Feature
+ * @id: id to identify the feature. 0 based
+ * @get_feat_size: max bytes required for Get Feature command for this Feature
+ * @set_feat_size: max bytes required for Set Feature command for this Feature
+ * @flags: attribute flags
+ * @get_feat_ver: Get Feature version
+ * @set_feat_ver: Set Feature version
+ * @effects: Set Feature command effects
+ * @reserved: reserved, must be 0
+ *
+ * CXL spec r3.2 Table 8-109
+ * Get Supported Features Supported Feature Entry
+ */
+struct cxl_feat_entry {
+	uuid_t uuid;
+	__le16 id;
+	__le16 get_feat_size;
+	__le16 set_feat_size;
+	__le32 flags;
+	__u8 get_feat_ver;
+	__u8 set_feat_ver;
+	__le16 effects;
+	__u8 reserved[18];
+} __attribute__ ((__packed__));
+
+/* @flags field for 'struct cxl_feat_entry' */
+#define CXL_FEATURE_F_CHANGEABLE		BIT(0)
+#define CXL_FEATURE_F_PERSIST_FW_UPDATE		BIT(4)
+#define CXL_FEATURE_F_DEFAULT_SEL		BIT(5)
+#define CXL_FEATURE_F_SAVED_SEL			BIT(6)
+
+/*
+ * struct cxl_mbox_get_sup_feats_out - Get Supported Features output
+ * @num_entries: number of Supported Feature Entries returned
+ * @supported_feats: number of supported Features
+ * @reserved: reserved, must be 0s.
+ * @ents: Supported Feature Entries array
+ *
+ * CXL spec r3.2 Table 8-108
+ * Get supported Features Output Payload
+ */
+struct cxl_mbox_get_sup_feats_out {
+	__struct_group(cxl_mbox_get_sup_feats_out_hdr, hdr, /* no attrs */,
+		__le16 num_entries;
+		__le16 supported_feats;
+		__u8 reserved[4];
+	);
+	struct cxl_feat_entry ents[] __counted_by_le(num_entries);
+} __attribute__ ((__packed__));
+
+/*
+ * Get Feature CXL spec r3.2 Spec 8.2.9.6.2
+ */
+
+/*
+ * struct cxl_mbox_get_feat_in - Get Feature input
+ * @uuid: UUID for Feature
+ * @offset: offset of the first byte in Feature data for output payload
+ * @count: count in bytes of Feature data returned
+ * @selection: 0 current value, 1 default value, 2 saved value
+ *
+ * CXL spec r3.2 section 8.2.9.6.2 Table 8-99
+ */
+struct cxl_mbox_get_feat_in {
+	uuid_t uuid;
+	__le16 offset;
+	__le16 count;
+	__u8 selection;
+} __attribute__ ((__packed__));
+
+/*
+ * enum cxl_get_feat_selection - selection field of Get Feature input
+ */
+enum cxl_get_feat_selection {
+	CXL_GET_FEAT_SEL_CURRENT_VALUE,
+	CXL_GET_FEAT_SEL_DEFAULT_VALUE,
+	CXL_GET_FEAT_SEL_SAVED_VALUE,
+	CXL_GET_FEAT_SEL_MAX
+};
+
+/*
+ * Set Feature CXL spec r3.2  8.2.9.6.3
+ */
+
+/*
+ * struct cxl_mbox_set_feat_in - Set Features input
+ * @uuid: UUID for Feature
+ * @flags: set feature flags
+ * @offset: byte offset of Feature data to update
+ * @version: Feature version of the data in Feature Data
+ * @rsvd: reserved, must be 0s.
+ * @feat_data: raw byte stream of Features data to update
+ *
+ * CXL spec r3.2 section 8.2.9.6.3 Table 8-101
+ */
+struct cxl_mbox_set_feat_in {
+	__struct_group(cxl_mbox_set_feat_hdr, hdr, /* no attrs */,
+		uuid_t uuid;
+		__le32 flags;
+		__le16 offset;
+		__u8 version;
+		__u8 rsvd[9];
+	);
+	__u8 feat_data[];
+}  __packed;
+
+/*
+ * enum cxl_set_feat_flag_data_transfer - Set Feature flags field
+ */
+enum cxl_set_feat_flag_data_transfer {
+	CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER = 0,
+	CXL_SET_FEAT_FLAG_INITIATE_DATA_TRANSFER,
+	CXL_SET_FEAT_FLAG_CONTINUE_DATA_TRANSFER,
+	CXL_SET_FEAT_FLAG_FINISH_DATA_TRANSFER,
+	CXL_SET_FEAT_FLAG_ABORT_DATA_TRANSFER,
+	CXL_SET_FEAT_FLAG_DATA_TRANSFER_MAX
+};
+
+#define CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK		GENMASK(2, 0)
+#define CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET	BIT(3)
+
+#endif
diff --git a/include/uapi/fwctl/cxl.h b/include/uapi/fwctl/cxl.h
new file mode 100644
index 0000000..43f522f
--- /dev/null
+++ b/include/uapi/fwctl/cxl.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2024-2025 Intel Corporation
+ *
+ * These are definitions for the mailbox command interface of CXL subsystem.
+ */
+#ifndef _UAPI_FWCTL_CXL_H_
+#define _UAPI_FWCTL_CXL_H_
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <cxl/features.h>
+
+/**
+ * struct fwctl_rpc_cxl - ioctl(FWCTL_RPC) input for CXL
+ * @opcode: CXL mailbox command opcode
+ * @flags: Flags for the command (input).
+ * @op_size: Size of input payload.
+ * @reserved1: Reserved. Must be 0s.
+ * @get_sup_feats_in: Get Supported Features input
+ * @get_feat_in: Get Feature input
+ * @set_feat_in: Set Feature input
+ */
+struct fwctl_rpc_cxl {
+	__struct_group(fwctl_rpc_cxl_hdr, hdr, /* no attrs */,
+		__u32 opcode;
+		__u32 flags;
+		__u32 op_size;
+		__u32 reserved1;
+	);
+	union {
+		struct cxl_mbox_get_sup_feats_in get_sup_feats_in;
+		struct cxl_mbox_get_feat_in get_feat_in;
+		struct cxl_mbox_set_feat_in set_feat_in;
+	};
+};
+
+/**
+ * struct fwctl_rpc_cxl_out - ioctl(FWCTL_RPC) output for CXL
+ * @size: Size of the output payload
+ * @retval: Return value from device
+ * @get_sup_feats_out: Get Supported Features output
+ * @payload: raw byte stream of payload
+ */
+struct fwctl_rpc_cxl_out {
+	__struct_group(fwctl_rpc_cxl_out_hdr, hdr, /* no attrs */,
+		__u32 size;
+		__u32 retval;
+	);
+	union {
+		struct cxl_mbox_get_sup_feats_out get_sup_feats_out;
+		__DECLARE_FLEX_ARRAY(__u8, payload);
+	};
+};
+
+#endif
diff --git a/include/uapi/fwctl/fwctl.h b/include/uapi/fwctl/fwctl.h
new file mode 100644
index 0000000..716ac0e
--- /dev/null
+++ b/include/uapi/fwctl/fwctl.h
@@ -0,0 +1,141 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Copyright (c) 2024-2025, NVIDIA CORPORATION & AFFILIATES.
+ */
+#ifndef _UAPI_FWCTL_H
+#define _UAPI_FWCTL_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+#define FWCTL_TYPE 0x9A
+
+/**
+ * DOC: General ioctl format
+ *
+ * The ioctl interface follows a general format to allow for extensibility. Each
+ * ioctl is passed a structure pointer as the argument providing the size of
+ * the structure in the first u32. The kernel checks that any structure space
+ * beyond what it understands is 0. This allows userspace to use the backward
+ * compatible portion while consistently using the newer, larger, structures.
+ *
+ * ioctls use a standard meaning for common errnos:
+ *
+ *  - ENOTTY: The IOCTL number itself is not supported at all
+ *  - E2BIG: The IOCTL number is supported, but the provided structure has
+ *    non-zero in a part the kernel does not understand.
+ *  - EOPNOTSUPP: The IOCTL number is supported, and the structure is
+ *    understood, however a known field has a value the kernel does not
+ *    understand or support.
+ *  - EINVAL: Everything about the IOCTL was understood, but a field is not
+ *    correct.
+ *  - ENOMEM: Out of memory.
+ *  - ENODEV: The underlying device has been hot-unplugged and the FD is
+ *            orphaned.
+ *
+ * As well as additional errnos, within specific ioctls.
+ */
+enum {
+	FWCTL_CMD_BASE = 0,
+	FWCTL_CMD_INFO = 0,
+	FWCTL_CMD_RPC = 1,
+};
+
+enum fwctl_device_type {
+	FWCTL_DEVICE_TYPE_ERROR = 0,
+	FWCTL_DEVICE_TYPE_MLX5 = 1,
+	FWCTL_DEVICE_TYPE_CXL = 2,
+	FWCTL_DEVICE_TYPE_PDS = 4,
+};
+
+/**
+ * struct fwctl_info - ioctl(FWCTL_INFO)
+ * @size: sizeof(struct fwctl_info)
+ * @flags: Must be 0
+ * @out_device_type: Returns the type of the device from enum fwctl_device_type
+ * @device_data_len: On input the length of the out_device_data memory. On
+ *	output the size of the kernel's device_data which may be larger or
+ *	smaller than the input. Maybe 0 on input.
+ * @out_device_data: Pointer to a memory of device_data_len bytes. Kernel will
+ *	fill the entire memory, zeroing as required.
+ *
+ * Returns basic information about this fwctl instance, particularly what driver
+ * is being used to define the device_data format.
+ */
+struct fwctl_info {
+	__u32 size;
+	__u32 flags;
+	__u32 out_device_type;
+	__u32 device_data_len;
+	__aligned_u64 out_device_data;
+};
+#define FWCTL_INFO _IO(FWCTL_TYPE, FWCTL_CMD_INFO)
+
+/**
+ * enum fwctl_rpc_scope - Scope of access for the RPC
+ *
+ * Refer to fwctl.rst for a more detailed discussion of these scopes.
+ */
+enum fwctl_rpc_scope {
+	/**
+	 * @FWCTL_RPC_CONFIGURATION: Device configuration access scope
+	 *
+	 * Read/write access to device configuration. When configuration
+	 * is written to the device it remains in a fully supported state.
+	 */
+	FWCTL_RPC_CONFIGURATION = 0,
+	/**
+	 * @FWCTL_RPC_DEBUG_READ_ONLY: Read only access to debug information
+	 *
+	 * Readable debug information. Debug information is compatible with
+	 * kernel lockdown, and does not disclose any sensitive information. For
+	 * instance exposing any encryption secrets from this information is
+	 * forbidden.
+	 */
+	FWCTL_RPC_DEBUG_READ_ONLY = 1,
+	/**
+	 * @FWCTL_RPC_DEBUG_WRITE: Writable access to lockdown compatible debug information
+	 *
+	 * Allows write access to data in the device which may leave a fully
+	 * supported state. This is intended to permit intensive and possibly
+	 * invasive debugging. This scope will taint the kernel.
+	 */
+	FWCTL_RPC_DEBUG_WRITE = 2,
+	/**
+	 * @FWCTL_RPC_DEBUG_WRITE_FULL: Write access to all debug information
+	 *
+	 * Allows read/write access to everything. Requires CAP_SYS_RAW_IO, so
+	 * it is not required to follow lockdown principals. If in doubt
+	 * debugging should be placed in this scope. This scope will taint the
+	 * kernel.
+	 */
+	FWCTL_RPC_DEBUG_WRITE_FULL = 3,
+};
+
+/**
+ * struct fwctl_rpc - ioctl(FWCTL_RPC)
+ * @size: sizeof(struct fwctl_rpc)
+ * @scope: One of enum fwctl_rpc_scope, required scope for the RPC
+ * @in_len: Length of the in memory
+ * @out_len: Length of the out memory
+ * @in: Request message in device specific format
+ * @out: Response message in device specific format
+ *
+ * Deliver a Remote Procedure Call to the device FW and return the response. The
+ * call's parameters and return are marshaled into linear buffers of memory. Any
+ * errno indicates that delivery of the RPC to the device failed. Return status
+ * originating in the device during a successful delivery must be encoded into
+ * out.
+ *
+ * The format of the buffers matches the out_device_type from FWCTL_INFO.
+ */
+struct fwctl_rpc {
+	__u32 size;
+	__u32 scope;
+	__u32 in_len;
+	__u32 out_len;
+	__aligned_u64 in;
+	__aligned_u64 out;
+};
+#define FWCTL_RPC _IO(FWCTL_TYPE, FWCTL_CMD_RPC)
+
+#endif
diff --git a/include/uapi/fwctl/mlx5.h b/include/uapi/fwctl/mlx5.h
new file mode 100644
index 0000000..6258191
--- /dev/null
+++ b/include/uapi/fwctl/mlx5.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2024-2025, NVIDIA CORPORATION & AFFILIATES
+ *
+ * These are definitions for the command interface for mlx5 HW. mlx5 FW has a
+ * User Context mechanism which allows the FW to understand a security scope.
+ * FWCTL binds each FD to a FW user context and then places the User Context ID
+ * (UID) in each command header. The created User Context has a capability set
+ * that is appropriate for FWCTL's security model.
+ *
+ * Command formation should use a copy of the structs in mlx5_ifc.h following
+ * the Programmers Reference Manual. A open release is available here:
+ *
+ *  https://network.nvidia.com/files/doc-2020/ethernet-adapters-programming-manual.pdf
+ *
+ * The device_type for this file is FWCTL_DEVICE_TYPE_MLX5.
+ */
+#ifndef _UAPI_FWCTL_MLX5_H
+#define _UAPI_FWCTL_MLX5_H
+
+#include <linux/types.h>
+
+/**
+ * struct fwctl_info_mlx5 - ioctl(FWCTL_INFO) out_device_data
+ * @uid: The FW UID this FD is bound to. Each command header will force
+ *	this value.
+ * @uctx_caps: The FW capabilities that are enabled for the uid.
+ *
+ * Return basic information about the FW interface available.
+ */
+struct fwctl_info_mlx5 {
+	__u32 uid;
+	__u32 uctx_caps;
+};
+
+#endif
diff --git a/include/uapi/fwctl/pds.h b/include/uapi/fwctl/pds.h
new file mode 100644
index 0000000..66be324
--- /dev/null
+++ b/include/uapi/fwctl/pds.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Copyright(c) Advanced Micro Devices, Inc */
+
+/*
+ * fwctl interface info for pds_fwctl
+ */
+
+#ifndef _UAPI_FWCTL_PDS_H_
+#define _UAPI_FWCTL_PDS_H_
+
+#include <linux/types.h>
+
+/**
+ * struct fwctl_info_pds
+ * @uctx_caps:  bitmap of firmware capabilities
+ *
+ * Return basic information about the FW interface available.
+ */
+struct fwctl_info_pds {
+	__u32 uctx_caps;
+};
+
+/**
+ * enum pds_fwctl_capabilities
+ * @PDS_FWCTL_QUERY_CAP: firmware can be queried for information
+ * @PDS_FWCTL_SEND_CAP:  firmware can be sent commands
+ */
+enum pds_fwctl_capabilities {
+	PDS_FWCTL_QUERY_CAP = 0,
+	PDS_FWCTL_SEND_CAP,
+};
+
+/**
+ * struct fwctl_rpc_pds
+ * @in.op:       requested operation code
+ * @in.ep:       firmware endpoint to operate on
+ * @in.rsvd:     reserved
+ * @in.len:      length of payload data
+ * @in.payload:  address of payload buffer
+ * @in:          rpc in parameters
+ * @out.retval:  operation result value
+ * @out.rsvd:    reserved
+ * @out.len:     length of result data buffer
+ * @out.payload: address of payload data buffer
+ * @out:         rpc out parameters
+ */
+struct fwctl_rpc_pds {
+	struct {
+		__u32 op;
+		__u32 ep;
+		__u32 rsvd;
+		__u32 len;
+		__aligned_u64 payload;
+	} in;
+	struct {
+		__u32 retval;
+		__u32 rsvd[2];
+		__u32 len;
+		__aligned_u64 payload;
+	} out;
+};
+#endif /* _UAPI_FWCTL_PDS_H_ */
diff --git a/kernel/panic.c b/kernel/panic.c
index d8635d5..0c55eec 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -511,6 +511,7 @@ const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = {
 	TAINT_FLAG(AUX,				'X', ' ', true),
 	TAINT_FLAG(RANDSTRUCT,			'T', ' ', true),
 	TAINT_FLAG(TEST,			'N', ' ', true),
+	TAINT_FLAG(FWCTL,			'J', ' ', true),
 };
 
 #undef TAINT_FLAG
diff --git a/tools/debugging/kernel-chktaint b/tools/debugging/kernel-chktaint
index 279be06..e7da090 100755
--- a/tools/debugging/kernel-chktaint
+++ b/tools/debugging/kernel-chktaint
@@ -204,6 +204,14 @@ else
 	echo " * an in-kernel test (such as a KUnit test) has been run (#18)"
 fi
 
+T=`expr $T / 2`
+if [ `expr $T % 2` -eq 0 ]; then
+	addout " "
+else
+	addout "J"
+	echo " * fwctl's mutating debug interface was used (#19)"
+fi
+
 echo "For a more detailed explanation of the various taint flags see"
 echo " Documentation/admin-guide/tainted-kernels.rst in the Linux kernel sources"
 echo " or https://kernel.org/doc/html/latest/admin-guide/tainted-kernels.html"
diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
index b1256fe..0a6572a 100644
--- a/tools/testing/cxl/Kbuild
+++ b/tools/testing/cxl/Kbuild
@@ -63,6 +63,7 @@ cxl_core-y += $(CXL_CORE_SRC)/pmu.o
 cxl_core-y += $(CXL_CORE_SRC)/cdat.o
 cxl_core-$(CONFIG_TRACING) += $(CXL_CORE_SRC)/trace.o
 cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o
+cxl_core-$(CONFIG_CXL_FEATURES) += $(CXL_CORE_SRC)/features.o
 cxl_core-y += config_check.o
 cxl_core-y += cxl_core_test.o
 cxl_core-y += cxl_core_exports.o
diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
index 8d731bd..9495dbc 100644
--- a/tools/testing/cxl/test/mem.c
+++ b/tools/testing/cxl/test/mem.c
@@ -45,6 +45,18 @@ static struct cxl_cel_entry mock_cel[] = {
 		.effect = CXL_CMD_EFFECT_NONE,
 	},
 	{
+		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_SUPPORTED_FEATURES),
+		.effect = CXL_CMD_EFFECT_NONE,
+	},
+	{
+		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_FEATURE),
+		.effect = CXL_CMD_EFFECT_NONE,
+	},
+	{
+		.opcode = cpu_to_le16(CXL_MBOX_OP_SET_FEATURE),
+		.effect = cpu_to_le16(EFFECT(CONF_CHANGE_IMMEDIATE)),
+	},
+	{
 		.opcode = cpu_to_le16(CXL_MBOX_OP_IDENTIFY),
 		.effect = CXL_CMD_EFFECT_NONE,
 	},
@@ -145,6 +157,10 @@ struct mock_event_store {
 	u32 ev_status;
 };
 
+struct vendor_test_feat {
+	__le32 data;
+} __packed;
+
 struct cxl_mockmem_data {
 	void *lsa;
 	void *fw;
@@ -161,6 +177,7 @@ struct cxl_mockmem_data {
 	u8 event_buf[SZ_4K];
 	u64 timestamp;
 	unsigned long sanitize_timeout;
+	struct vendor_test_feat test_feat;
 };
 
 static struct mock_event_log *event_find_log(struct device *dev, int log_type)
@@ -1354,6 +1371,151 @@ static int mock_activate_fw(struct cxl_mockmem_data *mdata,
 	return -EINVAL;
 }
 
+#define CXL_VENDOR_FEATURE_TEST							\
+	UUID_INIT(0xffffffff, 0xffff, 0xffff, 0xff, 0xff, 0xff, 0xff, 0xff,	\
+		  0xff, 0xff, 0xff)
+
+static void fill_feature_vendor_test(struct cxl_feat_entry *feat)
+{
+	feat->uuid = CXL_VENDOR_FEATURE_TEST;
+	feat->id = 0;
+	feat->get_feat_size = cpu_to_le16(0x4);
+	feat->set_feat_size = cpu_to_le16(0x4);
+	feat->flags = cpu_to_le32(CXL_FEATURE_F_CHANGEABLE |
+				  CXL_FEATURE_F_DEFAULT_SEL |
+				  CXL_FEATURE_F_SAVED_SEL);
+	feat->get_feat_ver = 1;
+	feat->set_feat_ver = 1;
+	feat->effects = cpu_to_le16(CXL_CMD_CONFIG_CHANGE_COLD_RESET |
+				    CXL_CMD_EFFECTS_VALID);
+}
+
+#define MAX_CXL_TEST_FEATS	1
+
+static int mock_get_test_feature(struct cxl_mockmem_data *mdata,
+				 struct cxl_mbox_cmd *cmd)
+{
+	struct vendor_test_feat *output = cmd->payload_out;
+	struct cxl_mbox_get_feat_in *input = cmd->payload_in;
+	u16 offset = le16_to_cpu(input->offset);
+	u16 count = le16_to_cpu(input->count);
+	u8 *ptr;
+
+	if (offset > sizeof(*output)) {
+		cmd->return_code = CXL_MBOX_CMD_RC_INPUT;
+		return -EINVAL;
+	}
+
+	if (offset + count > sizeof(*output)) {
+		cmd->return_code = CXL_MBOX_CMD_RC_INPUT;
+		return -EINVAL;
+	}
+
+	ptr = (u8 *)&mdata->test_feat + offset;
+	memcpy((u8 *)output + offset, ptr, count);
+
+	return 0;
+}
+
+static int mock_get_feature(struct cxl_mockmem_data *mdata,
+			    struct cxl_mbox_cmd *cmd)
+{
+	struct cxl_mbox_get_feat_in *input = cmd->payload_in;
+
+	if (uuid_equal(&input->uuid, &CXL_VENDOR_FEATURE_TEST))
+		return mock_get_test_feature(mdata, cmd);
+
+	cmd->return_code = CXL_MBOX_CMD_RC_UNSUPPORTED;
+
+	return -EOPNOTSUPP;
+}
+
+static int mock_set_test_feature(struct cxl_mockmem_data *mdata,
+				 struct cxl_mbox_cmd *cmd)
+{
+	struct cxl_mbox_set_feat_in *input = cmd->payload_in;
+	struct vendor_test_feat *test =
+		(struct vendor_test_feat *)input->feat_data;
+	u32 action;
+
+	action = FIELD_GET(CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK,
+			   le32_to_cpu(input->hdr.flags));
+	/*
+	 * While it is spec compliant to support other set actions, it is not
+	 * necessary to add the complication in the emulation currently. Reject
+	 * anything besides full xfer.
+	 */
+	if (action != CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER) {
+		cmd->return_code = CXL_MBOX_CMD_RC_INPUT;
+		return -EINVAL;
+	}
+
+	/* Offset should be reserved when doing full transfer */
+	if (input->hdr.offset) {
+		cmd->return_code = CXL_MBOX_CMD_RC_INPUT;
+		return -EINVAL;
+	}
+
+	memcpy(&mdata->test_feat.data, &test->data, sizeof(u32));
+
+	return 0;
+}
+
+static int mock_set_feature(struct cxl_mockmem_data *mdata,
+			    struct cxl_mbox_cmd *cmd)
+{
+	struct cxl_mbox_set_feat_in *input = cmd->payload_in;
+
+	if (uuid_equal(&input->hdr.uuid, &CXL_VENDOR_FEATURE_TEST))
+		return mock_set_test_feature(mdata, cmd);
+
+	cmd->return_code = CXL_MBOX_CMD_RC_UNSUPPORTED;
+
+	return -EOPNOTSUPP;
+}
+
+static int mock_get_supported_features(struct cxl_mockmem_data *mdata,
+				       struct cxl_mbox_cmd *cmd)
+{
+	struct cxl_mbox_get_sup_feats_in *in = cmd->payload_in;
+	struct cxl_mbox_get_sup_feats_out *out = cmd->payload_out;
+	struct cxl_feat_entry *feat;
+	u16 start_idx, count;
+
+	if (cmd->size_out < sizeof(*out)) {
+		cmd->return_code = CXL_MBOX_CMD_RC_PAYLOADLEN;
+		return -EINVAL;
+	}
+
+	/*
+	 * Current emulation only supports 1 feature
+	 */
+	start_idx = le16_to_cpu(in->start_idx);
+	if (start_idx != 0) {
+		cmd->return_code = CXL_MBOX_CMD_RC_INPUT;
+		return -EINVAL;
+	}
+
+	count = le16_to_cpu(in->count);
+	if (count < struct_size(out, ents, 0)) {
+		cmd->return_code = CXL_MBOX_CMD_RC_PAYLOADLEN;
+		return -EINVAL;
+	}
+
+	out->supported_feats = cpu_to_le16(MAX_CXL_TEST_FEATS);
+	cmd->return_code = 0;
+	if (count < struct_size(out, ents, MAX_CXL_TEST_FEATS)) {
+		out->num_entries = 0;
+		return 0;
+	}
+
+	out->num_entries = cpu_to_le16(MAX_CXL_TEST_FEATS);
+	feat = out->ents;
+	fill_feature_vendor_test(feat);
+
+	return 0;
+}
+
 static int cxl_mock_mbox_send(struct cxl_mailbox *cxl_mbox,
 			      struct cxl_mbox_cmd *cmd)
 {
@@ -1439,6 +1601,15 @@ static int cxl_mock_mbox_send(struct cxl_mailbox *cxl_mbox,
 	case CXL_MBOX_OP_ACTIVATE_FW:
 		rc = mock_activate_fw(mdata, cmd);
 		break;
+	case CXL_MBOX_OP_GET_SUPPORTED_FEATURES:
+		rc = mock_get_supported_features(mdata, cmd);
+		break;
+	case CXL_MBOX_OP_GET_FEATURE:
+		rc = mock_get_feature(mdata, cmd);
+		break;
+	case CXL_MBOX_OP_SET_FEATURE:
+		rc = mock_set_feature(mdata, cmd);
+		break;
 	default:
 		break;
 	}
@@ -1486,6 +1657,11 @@ static int cxl_mock_mailbox_create(struct cxl_dev_state *cxlds)
 	return 0;
 }
 
+static void cxl_mock_test_feat_init(struct cxl_mockmem_data *mdata)
+{
+	mdata->test_feat.data = cpu_to_le32(0xdeadbeef);
+}
+
 static int cxl_mock_mem_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -1558,6 +1734,10 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	if (rc)
 		return rc;
 
+	rc = devm_cxl_setup_features(cxlds);
+	if (rc)
+		dev_dbg(dev, "No CXL Features discovered\n");
+
 	cxl_mock_add_event_logs(&mdata->mes);
 
 	cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlds);
@@ -1572,7 +1752,12 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	if (rc)
 		return rc;
 
+	rc = devm_cxl_setup_fwctl(cxlmd);
+	if (rc)
+		dev_dbg(dev, "No CXL FWCTL setup\n");
+
 	cxl_mem_get_event_records(mds, CXLDEV_EVENT_STATUS_ALL);
+	cxl_mock_test_feat_init(mdata);
 
 	return 0;
 }
