projects/linux·commit b9500546

ST SPEAr: PCIE gadget suppport

b9500546 · Pratyush Anand <[email protected]> · 2011-03-22 16:33:58 -07:00

This is a configurable gadget.  can be configured by configfs interface.
Any IP available at PCIE bus can be programmed to be used by host
controller.It supoorts both INTX and MSI.

By default, the gadget is configured for INTX and SYSRAM1 is mapped to
BAR0 with size 0x1000

Signed-off-by: Pratyush Anand <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Jesse Barnes <[email protected]>
Cc: Viresh Kumar <[email protected]>
Cc: Shiraz Hashim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Commit
b9500546d5f85b56359657e1f78334db8de851fd
Parents
45bff2ea

Changes

5 files changed · +1080 −0

Only the first 600 diff lines are shown. Download the complete patch.

Documentation/ABI/testing/configfs-spear-pcie-gadget

View file
diff --git a/Documentation/ABI/testing/configfs-spear-pcie-gadget b/Documentation/ABI/testing/configfs-spear-pcie-gadget
new file mode 100644
index 0000000..8759881
--- /dev/null
+++ b/Documentation/ABI/testing/configfs-spear-pcie-gadget
@@ -0,0 +1,31 @@
+What: /config/pcie-gadget
+Date: Feb 2011
+KernelVersion: 2.6.37
+Contact: Pratyush Anand <[email protected]>
+Description:
+
+ Interface is used to configure selected dual mode PCIe controller
+ as device and then program its various registers to configure it
+ as a particular device type.
+ This interfaces can be used to show spear's PCIe device capability.
+
+ Nodes are only visible when configfs is mounted. To mount configfs
+ in /config directory use:
+ # mount -t configfs none /config/
+
+ For nth PCIe Device Controller
+ /config/pcie-gadget.n/
+ link ... used to enable ltssm and read its status.
+ int_type ...used to configure and read type of supported
+ interrupt
+ no_of_msi ... used to configure number of MSI vector needed and
+ to read no of MSI granted.
+ inta ... write 1 to assert INTA and 0 to de-assert.
+ send_msi ... write MSI vector to be sent.
+ vendor_id ... used to write and read vendor id (hex)
+ device_id ... used to write and read device id (hex)
+ bar0_size ... used to write and read bar0_size
+ bar0_address ... used to write and read bar0 mapped area in hex.
+ bar0_rw_offset ... used to write and read offset of bar0 where
+ bar0_data will be written or read.
+ bar0_data ... used to write and read data at bar0_rw_offset.

Documentation/misc-devices/spear-pcie-gadget.txt

View file
diff --git a/Documentation/misc-devices/spear-pcie-gadget.txt b/Documentation/misc-devices/spear-pcie-gadget.txt
new file mode 100644
index 0000000..02c13ef
--- /dev/null
+++ b/Documentation/misc-devices/spear-pcie-gadget.txt
@@ -0,0 +1,130 @@
+Spear PCIe Gadget Driver:
+
+Author
+=============
+Pratyush Anand ([email protected])
+
+Location
+============
+driver/misc/spear13xx_pcie_gadget.c
+
+Supported Chip:
+===================
+SPEAr1300
+SPEAr1310
+
+Menuconfig option:
+==========================
+Device Drivers
+ Misc devices
+ PCIe gadget support for SPEAr13XX platform
+purpose
+===========
+This driver has several nodes which can be read/written by configfs interface.
+Its main purpose is to configure selected dual mode PCIe controller as device
+and then program its various registers to configure it as a particular device
+type. This driver can be used to show spear's PCIe device capability.
+
+Description of different nodes:
+=================================
+
+read behavior of nodes:
+------------------------------
+link :gives ltssm status.
+int_type :type of supported interrupt
+no_of_msi :zero if MSI is not enabled by host. A positive value is the
+ number of MSI vector granted.
+vendor_id :returns programmed vendor id (hex)
+device_id :returns programmed device id(hex)
+bar0_size: :returns size of bar0 in hex.
+bar0_address :returns address of bar0 mapped area in hex.
+bar0_rw_offset :returns offset of bar0 for which bar0_data will return value.
+bar0_data :returns data at bar0_rw_offset.
+
+write behavior of nodes:
+------------------------------
+link :write UP to enable ltsmm DOWN to disable
+int_type :write interrupt type to be configured and (int_type could be
+ INTA, MSI or NO_INT). Select MSI only when you have programmed
+ no_of_msi node.
+no_of_msi :number of MSI vector needed.
+inta :write 1 to assert INTA and 0 to de-assert.
+send_msi :write MSI vector to be sent.
+vendor_id :write vendor id(hex) to be programmed.
+device_id :write device id(hex) to be programmed.
+bar0_size :write size of bar0 in hex. default bar0 size is 1000 (hex)
+ bytes.
+bar0_address :write address of bar0 mapped area in hex. (default mapping of
+ bar0 is SYSRAM1(E0800000). Always program bar size before bar
+ address. Kernel might modify bar size and address for alignment, so
+ read back bar size and address after writing to cross check.
+bar0_rw_offset :write offset of bar0 for which bar0_data will write value.
+bar0_data :write data to be written at bar0_rw_offset.
+
+Node programming example
+===========================
+Program all PCIe registers in such a way that when this device is connected
+to the PCIe host, then host sees this device as 1MB RAM.
+#mount -t configfs none /Config
+For nth PCIe Device Controller
+# cd /config/pcie_gadget.n/
+Now you have all the nodes in this directory.
+program vendor id as 0x104a
+# echo 104A >> vendor_id
+
+program device id as 0xCD80
+# echo CD80 >> device_id
+
+program BAR0 size as 1MB
+# echo 100000 >> bar0_size
+
+check for programmed bar0 size
+# cat bar0_size
+
+Program BAR0 Address as DDR (0x2100000). This is the physical address of
+memory, which is to be made visible to PCIe host. Similarly any other peripheral
+can also be made visible to PCIe host. E.g., if you program base address of UART
+as BAR0 address then when this device will be connected to a host, it will be
+visible as UART.
+# echo 2100000 >> bar0_address
+
+program interrupt type : INTA
+# echo INTA >> int_type
+
+go for link up now.
+# echo UP >> link
+
+It will have to be insured that, once link up is done on gadget, then only host
+is initialized and start to search PCIe devices on its port.
+
+/*wait till link is up*/
+# cat link
+wait till it returns UP.
+
+To assert INTA
+# echo 1 >> inta
+
+To de-assert INTA
+# echo 0 >> inta
+
+if MSI is to be used as interrupt, program no of msi vector needed (say4)
+# echo 4 >> no_of_msi
+
+select MSI as interrupt type
+# echo MSI >> int_type
+
+go for link up now
+# echo UP >> link
+
+wait till link is up
+# cat link
+An application can repetitively read this node till link is found UP. It can
+sleep between two read.
+
+wait till msi is enabled
+# cat no_of_msi
+Should return 4 (number of requested MSI vector)
+
+to send msi vector 2
+# echo 2 >> send_msi
+#cd -

drivers/misc/Kconfig

View file
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 203500d..4e007c6 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -402,6 +402,16 @@ config DS1682
This driver can also be built as a module. If so, the module
will be called ds1682.
+config SPEAR13XX_PCIE_GADGET
+ bool "PCIe gadget support for SPEAr13XX platform"
+ depends on ARCH_SPEAR13XX
+ default n
+ help
+ This option enables gadget support for PCIe controller. If
+ board file defines any controller as PCIe endpoint then a sysfs
+ entry will be created for that controller. User can use these
+ sysfs node to configure PCIe EP as per his requirements.
+
config TI_DAC7512
tristate "Texas Instruments DAC7512"
depends on SPI && SYSFS

drivers/misc/Makefile

View file
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 804f421..f546860 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_IWMC3200TOP) += iwmc3200top/
obj-$(CONFIG_HMC6352) += hmc6352.o
obj-y += eeprom/
obj-y += cb710/
+obj-$(CONFIG_SPEAR13XX_PCIE_GADGET) += spear13xx_pcie_gadget.o
obj-$(CONFIG_VMWARE_BALLOON) += vmw_balloon.o
obj-$(CONFIG_ARM_CHARLCD) += arm-charlcd.o
obj-$(CONFIG_PCH_PHUB) += pch_phub.o

drivers/misc/spear13xx_pcie_gadget.c

View file
diff --git a/drivers/misc/spear13xx_pcie_gadget.c b/drivers/misc/spear13xx_pcie_gadget.c
new file mode 100644
index 0000000..ec3b8c9
--- /dev/null
+++ b/drivers/misc/spear13xx_pcie_gadget.c
@@ -0,0 +1,908 @@
+/*
+ * drivers/misc/spear13xx_pcie_gadget.c
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * Pratyush Anand<[email protected]>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pci_regs.h>
+#include <linux/configfs.h>
+#include <mach/pcie.h>
+#include <mach/misc_regs.h>
+
+#define IN0_MEM_SIZE (200 * 1024 * 1024 - 1)
+/* In current implementation address translation is done using IN0 only.
+ * So IN1 start address and IN0 end address has been kept same
+*/
+#define IN1_MEM_SIZE (0 * 1024 * 1024 - 1)
+#define IN_IO_SIZE (20 * 1024 * 1024 - 1)
+#define IN_CFG0_SIZE (12 * 1024 * 1024 - 1)
+#define IN_CFG1_SIZE (12 * 1024 * 1024 - 1)
+#define IN_MSG_SIZE (12 * 1024 * 1024 - 1)
+/* Keep default BAR size as 4K*/
+/* AORAM would be mapped by default*/
+#define INBOUND_ADDR_MASK (SPEAR13XX_SYSRAM1_SIZE - 1)
+
+#define INT_TYPE_NO_INT 0
+#define INT_TYPE_INTX 1
+#define INT_TYPE_MSI 2
+struct spear_pcie_gadget_config {
+ void __iomem *base;
+ void __iomem *va_app_base;
+ void __iomem *va_dbi_base;
+ char int_type[10];
+ ulong requested_msi;
+ ulong configured_msi;
+ ulong bar0_size;
+ ulong bar0_rw_offset;
+ void __iomem *va_bar0_address;
+};
+
+struct pcie_gadget_target {
+ struct configfs_subsystem subsys;
+ struct spear_pcie_gadget_config config;
+};
+
+struct pcie_gadget_target_attr {
+ struct configfs_attribute attr;
+ ssize_t (*show)(struct spear_pcie_gadget_config *config,
+ char *buf);
+ ssize_t (*store)(struct spear_pcie_gadget_config *config,
+ const char *buf,
+ size_t count);
+};
+
+static void enable_dbi_access(struct pcie_app_reg __iomem *app_reg)
+{
+ /* Enable DBI access */
+ writel(readl(&app_reg->slv_armisc) | (1 << AXI_OP_DBI_ACCESS_ID),
+ &app_reg->slv_armisc);
+ writel(readl(&app_reg->slv_awmisc) | (1 << AXI_OP_DBI_ACCESS_ID),
+ &app_reg->slv_awmisc);
+
+}
+
+static void disable_dbi_access(struct pcie_app_reg __iomem *app_reg)
+{
+ /* disable DBI access */
+ writel(readl(&app_reg->slv_armisc) & ~(1 << AXI_OP_DBI_ACCESS_ID),
+ &app_reg->slv_armisc);
+ writel(readl(&app_reg->slv_awmisc) & ~(1 << AXI_OP_DBI_ACCESS_ID),
+ &app_reg->slv_awmisc);
+
+}
+
+static void spear_dbi_read_reg(struct spear_pcie_gadget_config *config,
+ int where, int size, u32 *val)
+{
+ struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+ ulong va_address;
+
+ /* Enable DBI access */
+ enable_dbi_access(app_reg);
+
+ va_address = (ulong)config->va_dbi_base + (where & ~0x3);
+
+ *val = readl(va_address);
+
+ if (size == 1)
+ *val = (*val >> (8 * (where & 3))) & 0xff;
+ else if (size == 2)
+ *val = (*val >> (8 * (where & 3))) & 0xffff;
+
+ /* Disable DBI access */
+ disable_dbi_access(app_reg);
+}
+
+static void spear_dbi_write_reg(struct spear_pcie_gadget_config *config,
+ int where, int size, u32 val)
+{
+ struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+ ulong va_address;
+
+ /* Enable DBI access */
+ enable_dbi_access(app_reg);
+
+ va_address = (ulong)config->va_dbi_base + (where & ~0x3);
+
+ if (size == 4)
+ writel(val, va_address);
+ else if (size == 2)
+ writew(val, va_address + (where & 2));
+ else if (size == 1)
+ writeb(val, va_address + (where & 3));
+
+ /* Disable DBI access */
+ disable_dbi_access(app_reg);
+}
+
+#define PCI_FIND_CAP_TTL 48
+
+static int pci_find_own_next_cap_ttl(struct spear_pcie_gadget_config *config,
+ u32 pos, int cap, int *ttl)
+{
+ u32 id;
+
+ while ((*ttl)--) {
+ spear_dbi_read_reg(config, pos, 1, &pos);
+ if (pos < 0x40)
+ break;
+ pos &= ~3;
+ spear_dbi_read_reg(config, pos + PCI_CAP_LIST_ID, 1, &id);
+ if (id == 0xff)
+ break;
+ if (id == cap)
+ return pos;
+ pos += PCI_CAP_LIST_NEXT;
+ }
+ return 0;
+}
+
+static int pci_find_own_next_cap(struct spear_pcie_gadget_config *config,
+ u32 pos, int cap)
+{
+ int ttl = PCI_FIND_CAP_TTL;
+
+ return pci_find_own_next_cap_ttl(config, pos, cap, &ttl);
+}
+
+static int pci_find_own_cap_start(struct spear_pcie_gadget_config *config,
+ u8 hdr_type)
+{
+ u32 status;
+
+ spear_dbi_read_reg(config, PCI_STATUS, 2, &status);
+ if (!(status & PCI_STATUS_CAP_LIST))
+ return 0;
+
+ switch (hdr_type) {
+ case PCI_HEADER_TYPE_NORMAL:
+ case PCI_HEADER_TYPE_BRIDGE:
+ return PCI_CAPABILITY_LIST;
+ case PCI_HEADER_TYPE_CARDBUS:
+ return PCI_CB_CAPABILITY_LIST;
+ default:
+ return 0;
+ }
+
+ return 0;
+}
+
+/*
+ * Tell if a device supports a given PCI capability.
+ * Returns the address of the requested capability structure within the
+ * device's PCI configuration space or 0 in case the device does not
+ * support it. Possible values for @cap:
+ *
+ * %PCI_CAP_ID_PM Power Management
+ * %PCI_CAP_ID_AGP Accelerated Graphics Port
+ * %PCI_CAP_ID_VPD Vital Product Data
+ * %PCI_CAP_ID_SLOTID Slot Identification
+ * %PCI_CAP_ID_MSI Message Signalled Interrupts
+ * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
+ * %PCI_CAP_ID_PCIX PCI-X
+ * %PCI_CAP_ID_EXP PCI Express
+ */
+static int pci_find_own_capability(struct spear_pcie_gadget_config *config,
+ int cap)
+{
+ u32 pos;
+ u32 hdr_type;
+
+ spear_dbi_read_reg(config, PCI_HEADER_TYPE, 1, &hdr_type);
+
+ pos = pci_find_own_cap_start(config, hdr_type);
+ if (pos)
+ pos = pci_find_own_next_cap(config, pos, cap);
+
+ return pos;
+}
+
+static irqreturn_t spear_pcie_gadget_irq(int irq, void *dev_id)
+{
+ return 0;
+}
+
+/*
+ * configfs interfaces show/store functions
+ */
+static ssize_t pcie_gadget_show_link(
+ struct spear_pcie_gadget_config *config,
+ char *buf)
+{
+ struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+
+ if (readl(&app_reg->app_status_1) & ((u32)1 << XMLH_LINK_UP_ID))
+ return sprintf(buf, "UP");
+ else
+ return sprintf(buf, "DOWN");
+}
+
+static ssize_t pcie_gadget_store_link(
+ struct spear_pcie_gadget_config *config,
+ const char *buf, size_t count)
+{
+ struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+
+ if (sysfs_streq(buf, "UP"))
+ writel(readl(&app_reg->app_ctrl_0) | (1 << APP_LTSSM_ENABLE_ID),
+ &app_reg->app_ctrl_0);
+ else if (sysfs_streq(buf, "DOWN"))
+ writel(readl(&app_reg->app_ctrl_0)
+ & ~(1 << APP_LTSSM_ENABLE_ID),
+ &app_reg->app_ctrl_0);
+ else
+ return -EINVAL;
+ return count;
+}
+
+static ssize_t pcie_gadget_show_int_type(
+ struct spear_pcie_gadget_config *config,
+ char *buf)
+{
+ return sprintf(buf, "%s", config->int_type);
+}
+
+static ssize_t pcie_gadget_store_int_type(
+ struct spear_pcie_gadget_config *config,
+ const char *buf, size_t count)
+{
+ u32 cap, vec, flags;
+ ulong vector;
+
+ if (sysfs_streq(buf, "INTA"))
+ spear_dbi_write_reg(config, PCI_INTERRUPT_LINE, 1, 1);
+
+ else if (sysfs_streq(buf, "MSI")) {
+ vector = config->requested_msi;
+ vec = 0;
+ while (vector > 1) {
+ vector /= 2;
+ vec++;
+ }
+ spear_dbi_write_reg(config, PCI_INTERRUPT_LINE, 1, 0);
+ cap = pci_find_own_capability(config, PCI_CAP_ID_MSI);
+ spear_dbi_read_reg(config, cap + PCI_MSI_FLAGS, 1, &flags);
+ flags &= ~PCI_MSI_FLAGS_QMASK;
+ flags |= vec << 1;
+ spear_dbi_write_reg(config, cap + PCI_MSI_FLAGS, 1, flags);
+ } else
+ return -EINVAL;
+
+ strcpy(config->int_type, buf);
+
+ return count;
+}
+
+static ssize_t pcie_gadget_show_no_of_msi(
+ struct spear_pcie_gadget_config *config,
+ char *buf)
+{
+ struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+ u32 cap, vec, flags;
+ ulong vector;
+
+ if ((readl(&app_reg->msg_status) & (1 << CFG_MSI_EN_ID))
+ != (1 << CFG_MSI_EN_ID))
+ vector = 0;
+ else {
+ cap = pci_find_own_capability(config, PCI_CAP_ID_MSI);
+ spear_dbi_read_reg(config, cap + PCI_MSI_FLAGS, 1, &flags);
+ flags &= ~PCI_MSI_FLAGS_QSIZE;
+ vec = flags >> 4;
+ vector = 1;
+ while (vec--)
+ vector *= 2;
+ }
+ config->configured_msi = vector;
+
+ return sprintf(buf, "%lu", vector);
+}
+
+static ssize_t pcie_gadget_store_no_of_msi(
+ struct spear_pcie_gadget_config *config,
+ const char *buf, size_t count)
+{
+ if (strict_strtoul(buf, 0, &config->requested_msi))
+ return -EINVAL;
+ if (config->requested_msi > 32)
+ config->requested_msi = 32;
+
+ return count;
+}
+
+static ssize_t pcie_gadget_store_inta(
+ struct spear_pcie_gadget_config *config,
+ const char *buf, size_t count)
+{
+ struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+ ulong en;
+
+ if (strict_strtoul(buf, 0, &en))
+ return -EINVAL;
+
+ if (en)
+ writel(readl(&app_reg->app_ctrl_0) | (1 << SYS_INT_ID),
+ &app_reg->app_ctrl_0);
+ else
+ writel(readl(&app_reg->app_ctrl_0) & ~(1 << SYS_INT_ID),
+ &app_reg->app_ctrl_0);
+
+ return count;
+}
+
+static ssize_t pcie_gadget_store_send_msi(
+ struct spear_pcie_gadget_config *config,
+ const char *buf, size_t count)
+{
+ struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+ ulong vector;
+ u32 ven_msi;
+
+ if (strict_strtoul(buf, 0, &vector))
+ return -EINVAL;
+
+ if (!config->configured_msi)
+ return -EINVAL;
+
+ if (vector >= config->configured_msi)
+ return -EINVAL;
+
+ ven_msi = readl(&app_reg->ven_msi_1);
+ ven_msi &= ~VEN_MSI_FUN_NUM_MASK;
+ ven_msi |= 0 << VEN_MSI_FUN_NUM_ID;
+ ven_msi &= ~VEN_MSI_TC_MASK;
+ ven_msi |= 0 << VEN_MSI_TC_ID;
+ ven_msi &= ~VEN_MSI_VECTOR_MASK;
+ ven_msi |= vector << VEN_MSI_VECTOR_ID;
+
+ /* generating interrupt for msi vector */
+ ven_msi |= VEN_MSI_REQ_EN;
+ writel(ven_msi, &app_reg->ven_msi_1);
+ udelay(1);
+ ven_msi &= ~VEN_MSI_REQ_EN;
+ writel(ven_msi, &app_reg->ven_msi_1);
+
+ return count;
+}
+
+static ssize_t pcie_gadget_show_vendor_id(
+ struct spear_pcie_gadget_config *config,
+ char *buf)
+{
+ u32 id;
+
+ spear_dbi_read_reg(config, PCI_VENDOR_ID, 2, &id);

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