Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock
Merge commit. Changes below are compared with the first parent: 30307c69.
Changes
11 files changed · +516 −226
| File | Status | Add | Del | Content |
|---|---|---|---|---|
| Documentation/hwspinlock.txt | modified | +44 | −30 | View file |
| MAINTAINERS | modified | +14 | −0 | View file |
| arch/arm/mach-omap2/hwspinlock.c | modified | +8 | −1 | View file |
| drivers/hwspinlock/Kconfig | modified | +18 | −9 | View file |
| drivers/hwspinlock/Makefile | modified | +1 | −0 | View file |
| drivers/hwspinlock/hwspinlock_core.c | modified | +127 | −77 | View file |
| drivers/hwspinlock/hwspinlock_internal.h | modified | +28 | −12 | View file |
| drivers/hwspinlock/omap_hwspinlock.c | modified | +43 | −84 | View file |
| drivers/hwspinlock/u8500_hsem.c | added | +198 | −0 | View file |
| drivers/mmc/host/omap_hsmmc.c | modified | +1 | −1 | View file |
| include/linux/hwspinlock.h | modified | +34 | −12 | View file |
Only the first 600 diff lines are shown. Download the complete patch.
Documentation/hwspinlock.txt
View filediff --git a/Documentation/hwspinlock.txt b/Documentation/hwspinlock.txt
index 7dcd1a4..a903ee5 100644
--- a/Documentation/hwspinlock.txt
+++ b/Documentation/hwspinlock.txt
@@ -39,23 +39,20 @@ independent, drivers.
in case an unused hwspinlock isn't available. Users of this
API will usually want to communicate the lock's id to the remote core
before it can be used to achieve synchronization.
- Can be called from an atomic context (this function will not sleep) but
- not from within interrupt context.
+ Should be called from a process context (might sleep).
struct hwspinlock *hwspin_lock_request_specific(unsigned int id);
- assign a specific hwspinlock id and return its address, or NULL
if that hwspinlock is already in use. Usually board code will
be calling this function in order to reserve specific hwspinlock
ids for predefined purposes.
- Can be called from an atomic context (this function will not sleep) but
- not from within interrupt context.
+ Should be called from a process context (might sleep).
int hwspin_lock_free(struct hwspinlock *hwlock);
- free a previously-assigned hwspinlock; returns 0 on success, or an
appropriate error code on failure (e.g. -EINVAL if the hwspinlock
is already free).
- Can be called from an atomic context (this function will not sleep) but
- not from within interrupt context.
+ Should be called from a process context (might sleep).
int hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int timeout);
- lock a previously-assigned hwspinlock with a timeout limit (specified in
@@ -230,45 +227,62 @@ int hwspinlock_example2(void)
4. API for implementors
- int hwspin_lock_register(struct hwspinlock *hwlock);
+ int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
+ const struct hwspinlock_ops *ops, int base_id, int num_locks);
- to be called from the underlying platform-specific implementation, in
- order to register a new hwspinlock instance. Can be called from an atomic
- context (this function will not sleep) but not from within interrupt
- context. Returns 0 on success, or appropriate error code on failure.
+ order to register a new hwspinlock device (which is usually a bank of
+ numerous locks). Should be called from a process context (this function
+ might sleep).
+ Returns 0 on success, or appropriate error code on failure.
- struct hwspinlock *hwspin_lock_unregister(unsigned int id);
+ int hwspin_lock_unregister(struct hwspinlock_device *bank);
- to be called from the underlying vendor-specific implementation, in order
- to unregister an existing (and unused) hwspinlock instance.
- Can be called from an atomic context (will not sleep) but not from
- within interrupt context.
+ to unregister an hwspinlock device (which is usually a bank of numerous
+ locks).
+ Should be called from a process context (this function might sleep).
Returns the address of hwspinlock on success, or NULL on error (e.g.
if the hwspinlock is sill in use).
-5. struct hwspinlock
+5. Important structs
-This struct represents an hwspinlock instance. It is registered by the
-underlying hwspinlock implementation using the hwspin_lock_register() API.
+struct hwspinlock_device is a device which usually contains a bank
+of hardware locks. It is registered by the underlying hwspinlock
+implementation using the hwspin_lock_register() API.
/**
- * struct hwspinlock - vendor-specific hwspinlock implementation
- *
- * @dev: underlying device, will be used with runtime PM api
- * @ops: vendor-specific hwspinlock handlers
- * @id: a global, unique, system-wide, index of the lock.
- * @lock: initialized and used by hwspinlock core
- * @owner: underlying implementation module, used to maintain module ref count
+ * struct hwspinlock_device - a device which usually spans numerous hwspinlocks
+ * @dev: underlying device, will be used to invoke runtime PM api
+ * @ops: platform-specific hwspinlock handlers
+ * @base_id: id index of the first lock in this device
+ * @num_locks: number of locks in this device
+ * @lock: dynamically allocated array of 'struct hwspinlock'
*/
-struct hwspinlock {
+struct hwspinlock_device {
struct device *dev;
const struct hwspinlock_ops *ops;
- int id;
+ int base_id;
+ int num_locks;
+ struct hwspinlock lock[0];
+};
+
+struct hwspinlock_device contains an array of hwspinlock structs, each
+of which represents a single hardware lock:
+
+/**
+ * struct hwspinlock - this struct represents a single hwspinlock instance
+ * @bank: the hwspinlock_device structure which owns this lock
+ * @lock: initialized and used by hwspinlock core
+ * @priv: private data, owned by the underlying platform-specific hwspinlock drv
+ */
+struct hwspinlock {
+ struct hwspinlock_device *bank;
spinlock_t lock;
- struct module *owner;
+ void *priv;
};
-The underlying implementation is responsible to assign the dev, ops, id and
-owner members. The lock member, OTOH, is initialized and used by the hwspinlock
-core.
+When registering a bank of locks, the hwspinlock driver only needs to
+set the priv members of the locks. The rest of the members are set and
+initialized by the hwspinlock core itself.
6. Implementation callbacks
MAINTAINERS
View filediff --git a/MAINTAINERS b/MAINTAINERS
index 4cb8c51..ab77670 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3018,6 +3018,13 @@ F: Documentation/hw_random.txt
F: drivers/char/hw_random/
F: include/linux/hw_random.h
+HARDWARE SPINLOCK CORE
+M: Ohad Ben-Cohen <[email protected]>
+S: Maintained
+F: Documentation/hwspinlock.txt
+F: drivers/hwspinlock/hwspinlock_*
+F: include/linux/hwspinlock.h
+
HARMONY SOUND DRIVER
M: Kyle McMartin <[email protected]>
@@ -4714,6 +4721,13 @@ S: Maintained
F: drivers/video/omap2/
F: Documentation/arm/OMAP/DSS
+OMAP HARDWARE SPINLOCK SUPPORT
+M: Ohad Ben-Cohen <[email protected]>
+S: Maintained
+F: drivers/hwspinlock/omap_hwspinlock.c
+F: arch/arm/mach-omap2/hwspinlock.c
+
OMAP MMC SUPPORT
M: Jarkko Lavinen <[email protected]>
arch/arm/mach-omap2/hwspinlock.c
View filediff --git a/arch/arm/mach-omap2/hwspinlock.c b/arch/arm/mach-omap2/hwspinlock.c
index 36e2109..454dfce 100644
--- a/arch/arm/mach-omap2/hwspinlock.c
+++ b/arch/arm/mach-omap2/hwspinlock.c
@@ -19,10 +19,15 @@
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
+#include <linux/hwspinlock.h>
#include <plat/omap_hwmod.h>
#include <plat/omap_device.h>
+static struct hwspinlock_pdata omap_hwspinlock_pdata __initdata = {
+ .base_id = 0,
+};
+
int __init hwspinlocks_init(void)
{
int retval = 0;
@@ -40,7 +45,9 @@ int __init hwspinlocks_init(void)
if (oh == NULL)
return -EINVAL;
- pdev = omap_device_build(dev_name, 0, oh, NULL, 0, NULL, 0, false);
+ pdev = omap_device_build(dev_name, 0, oh, &omap_hwspinlock_pdata,
+ sizeof(struct hwspinlock_pdata),
+ NULL, 0, false);
if (IS_ERR(pdev)) {
pr_err("Can't build omap_device for %s:%s\n", dev_name,
oh_name);
drivers/hwspinlock/Kconfig
View filediff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index 1f29bab..c7c3128 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -2,22 +2,31 @@
# Generic HWSPINLOCK framework
#
+# HWSPINLOCK always gets selected by whoever wants it.
config HWSPINLOCK
- tristate "Generic Hardware Spinlock framework"
- depends on ARCH_OMAP4
- help
- Say y here to support the generic hardware spinlock framework.
- You only need to enable this if you have hardware spinlock module
- on your system (usually only relevant if your system has remote slave
- coprocessors).
+ tristate
- If unsure, say N.
+menu "Hardware Spinlock drivers"
config HWSPINLOCK_OMAP
tristate "OMAP Hardware Spinlock device"
- depends on HWSPINLOCK && ARCH_OMAP4
+ depends on ARCH_OMAP4
+ select HWSPINLOCK
help
Say y here to support the OMAP Hardware Spinlock device (firstly
introduced in OMAP4).
If unsure, say N.
+
+config HSEM_U8500
+ tristate "STE Hardware Semaphore functionality"
+ depends on ARCH_U8500
+ select HWSPINLOCK
+ help
+ Say y here to support the STE Hardware Semaphore functionality, which
+ provides a synchronisation mechanism for the various processor on the
+ SoC.
+
+ If unsure, say N.
+
+endmenu
drivers/hwspinlock/Makefile
View filediff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index 5729a3f..93eb64b 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -4,3 +4,4 @@
obj-$(CONFIG_HWSPINLOCK) += hwspinlock_core.o
obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o
+obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o
drivers/hwspinlock/hwspinlock_core.c
View filediff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c
index 43a6271..61c9cf1 100644
--- a/drivers/hwspinlock/hwspinlock_core.c
+++ b/drivers/hwspinlock/hwspinlock_core.c
@@ -26,6 +26,7 @@
#include <linux/radix-tree.h>
#include <linux/hwspinlock.h>
#include <linux/pm_runtime.h>
+#include <linux/mutex.h>
#include "hwspinlock_internal.h"
@@ -52,10 +53,12 @@
static RADIX_TREE(hwspinlock_tree, GFP_KERNEL);
/*
- * Synchronization of access to the tree is achieved using this spinlock,
+ * Synchronization of access to the tree is achieved using this mutex,
* as the radix-tree API requires that users provide all synchronisation.
+ * A mutex is needed because we're using non-atomic radix tree allocations.
*/
-static DEFINE_SPINLOCK(hwspinlock_tree_lock);
+static DEFINE_MUTEX(hwspinlock_tree_lock);
+
/**
* __hwspin_trylock() - attempt to lock a specific hwspinlock
@@ -114,7 +117,7 @@ int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
return -EBUSY;
/* try to take the hwspinlock device */
- ret = hwlock->ops->trylock(hwlock);
+ ret = hwlock->bank->ops->trylock(hwlock);
/* if hwlock is already taken, undo spin_trylock_* and exit */
if (!ret) {
@@ -196,8 +199,8 @@ int __hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int to,
* Allow platform-specific relax handlers to prevent
* hogging the interconnect (no sleeping, though)
*/
- if (hwlock->ops->relax)
- hwlock->ops->relax(hwlock);
+ if (hwlock->bank->ops->relax)
+ hwlock->bank->ops->relax(hwlock);
}
return ret;
@@ -242,7 +245,7 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
*/
mb();
- hwlock->ops->unlock(hwlock);
+ hwlock->bank->ops->unlock(hwlock);
/* Undo the spin_trylock{_irq, _irqsave} called while locking */
if (mode == HWLOCK_IRQSTATE)
@@ -254,68 +257,37 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
}
EXPORT_SYMBOL_GPL(__hwspin_unlock);
-/**
- * hwspin_lock_register() - register a new hw spinlock
- * @hwlock: hwspinlock to register.
- *
- * This function should be called from the underlying platform-specific
- * implementation, to register a new hwspinlock instance.
- *
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context.
- *
- * Returns 0 on success, or an appropriate error code on failure
- */
-int hwspin_lock_register(struct hwspinlock *hwlock)
+static int hwspin_lock_register_single(struct hwspinlock *hwlock, int id)
{
struct hwspinlock *tmp;
int ret;
- if (!hwlock || !hwlock->ops ||
- !hwlock->ops->trylock || !hwlock->ops->unlock) {
- pr_err("invalid parameters\n");
- return -EINVAL;
- }
-
- spin_lock_init(&hwlock->lock);
-
- spin_lock(&hwspinlock_tree_lock);
+ mutex_lock(&hwspinlock_tree_lock);
- ret = radix_tree_insert(&hwspinlock_tree, hwlock->id, hwlock);
- if (ret)
+ ret = radix_tree_insert(&hwspinlock_tree, id, hwlock);
+ if (ret) {
+ if (ret == -EEXIST)
+ pr_err("hwspinlock id %d already exists!\n", id);
goto out;
+ }
/* mark this hwspinlock as available */
- tmp = radix_tree_tag_set(&hwspinlock_tree, hwlock->id,
- HWSPINLOCK_UNUSED);
+ tmp = radix_tree_tag_set(&hwspinlock_tree, id, HWSPINLOCK_UNUSED);
/* self-sanity check which should never fail */
WARN_ON(tmp != hwlock);
out:
- spin_unlock(&hwspinlock_tree_lock);
- return ret;
+ mutex_unlock(&hwspinlock_tree_lock);
+ return 0;
}
-EXPORT_SYMBOL_GPL(hwspin_lock_register);
-/**
- * hwspin_lock_unregister() - unregister an hw spinlock
- * @id: index of the specific hwspinlock to unregister
- *
- * This function should be called from the underlying platform-specific
- * implementation, to unregister an existing (and unused) hwspinlock.
- *
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context.
- *
- * Returns the address of hwspinlock @id on success, or NULL on failure
- */
-struct hwspinlock *hwspin_lock_unregister(unsigned int id)
+static struct hwspinlock *hwspin_lock_unregister_single(unsigned int id)
{
struct hwspinlock *hwlock = NULL;
int ret;
- spin_lock(&hwspinlock_tree_lock);
+ mutex_lock(&hwspinlock_tree_lock);
/* make sure the hwspinlock is not in use (tag is set) */
ret = radix_tree_tag_get(&hwspinlock_tree, id, HWSPINLOCK_UNUSED);
@@ -331,9 +303,91 @@ struct hwspinlock *hwspin_lock_unregister(unsigned int id)
}
out:
- spin_unlock(&hwspinlock_tree_lock);
+ mutex_unlock(&hwspinlock_tree_lock);
return hwlock;
}
+
+/**
+ * hwspin_lock_register() - register a new hw spinlock device
+ * @bank: the hwspinlock device, which usually provides numerous hw locks
+ * @dev: the backing device
+ * @ops: hwspinlock handlers for this device
+ * @base_id: id of the first hardware spinlock in this bank
+ * @num_locks: number of hwspinlocks provided by this device
+ *
+ * This function should be called from the underlying platform-specific
+ * implementation, to register a new hwspinlock device instance.
+ *
+ * Should be called from a process context (might sleep)
+ *
+ * Returns 0 on success, or an appropriate error code on failure
+ */
+int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
+ const struct hwspinlock_ops *ops, int base_id, int num_locks)
+{
+ struct hwspinlock *hwlock;
+ int ret = 0, i;
+
+ if (!bank || !ops || !dev || !num_locks || !ops->trylock ||
+ !ops->unlock) {
+ pr_err("invalid parameters\n");
+ return -EINVAL;
+ }
+
+ bank->dev = dev;
+ bank->ops = ops;
+ bank->base_id = base_id;
+ bank->num_locks = num_locks;
+
+ for (i = 0; i < num_locks; i++) {
+ hwlock = &bank->lock[i];
+
+ spin_lock_init(&hwlock->lock);
+ hwlock->bank = bank;
+
+ ret = hwspin_lock_register_single(hwlock, i);
+ if (ret)
+ goto reg_failed;
+ }
+
+ return 0;
+
+reg_failed:
+ while (--i >= 0)
+ hwspin_lock_unregister_single(i);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(hwspin_lock_register);
+
+/**
+ * hwspin_lock_unregister() - unregister an hw spinlock device
+ * @bank: the hwspinlock device, which usually provides numerous hw locks
+ *
+ * This function should be called from the underlying platform-specific
+ * implementation, to unregister an existing (and unused) hwspinlock.
+ *
+ * Should be called from a process context (might sleep)
+ *
+ * Returns 0 on success, or an appropriate error code on failure
+ */
+int hwspin_lock_unregister(struct hwspinlock_device *bank)
+{
+ struct hwspinlock *hwlock, *tmp;
+ int i;
+
+ for (i = 0; i < bank->num_locks; i++) {
+ hwlock = &bank->lock[i];
+
+ tmp = hwspin_lock_unregister_single(bank->base_id + i);
+ if (!tmp)
+ return -EBUSY;
+
+ /* self-sanity check that should never fail */
+ WARN_ON(tmp != hwlock);
+ }
+
+ return 0;
+}
EXPORT_SYMBOL_GPL(hwspin_lock_unregister);
/**
@@ -348,24 +402,25 @@ EXPORT_SYMBOL_GPL(hwspin_lock_unregister);
*/
static int __hwspin_lock_request(struct hwspinlock *hwlock)
{
+ struct device *dev = hwlock->bank->dev;
struct hwspinlock *tmp;
int ret;
/* prevent underlying implementation from being removed */
- if (!try_module_get(hwlock->owner)) {
- dev_err(hwlock->dev, "%s: can't get owner\n", __func__);
+ if (!try_module_get(dev->driver->owner)) {
+ dev_err(dev, "%s: can't get owner\n", __func__);
return -EINVAL;
}
/* notify PM core that power is now needed */
- ret = pm_runtime_get_sync(hwlock->dev);
+ ret = pm_runtime_get_sync(dev);
if (ret < 0) {
- dev_err(hwlock->dev, "%s: can't power on device\n", __func__);
+ dev_err(dev, "%s: can't power on device\n", __func__);
return ret;
}
/* mark hwspinlock as used, should not fail */
- tmp = radix_tree_tag_clear(&hwspinlock_tree, hwlock->id,
+ tmp = radix_tree_tag_clear(&hwspinlock_tree, hwlock_to_id(hwlock),
HWSPINLOCK_UNUSED);
/* self-sanity check that should never fail */
@@ -387,7 +442,7 @@ int hwspin_lock_get_id(struct hwspinlock *hwlock)
return -EINVAL;
}
- return hwlock->id;
+ return hwlock_to_id(hwlock);
}
EXPORT_SYMBOL_GPL(hwspin_lock_get_id);
@@ -400,9 +455,7 @@ EXPORT_SYMBOL_GPL(hwspin_lock_get_id);
* to the remote core before it can be used for synchronization (to get the
* id of a given hwlock, use hwspin_lock_get_id()).
*
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context (simply because there is no use case for
- * that yet).
+ * Should be called from a process context (might sleep)
*
* Returns the address of the assigned hwspinlock, or NULL on error
*/
@@ -411,7 +464,7 @@ struct hwspinlock *hwspin_lock_request(void)
struct hwspinlock *hwlock;
int ret;
- spin_lock(&hwspinlock_tree_lock);
+ mutex_lock(&hwspinlock_tree_lock);
/* look for an unused lock */
ret = radix_tree_gang_lookup_tag(&hwspinlock_tree, (void **)&hwlock,
@@ -431,7 +484,7 @@ struct hwspinlock *hwspin_lock_request(void)
hwlock = NULL;
out:
- spin_unlock(&hwspinlock_tree_lock);
+ mutex_unlock(&hwspinlock_tree_lock);
return hwlock;
}
EXPORT_SYMBOL_GPL(hwspin_lock_request);
@@ -445,9 +498,7 @@ EXPORT_SYMBOL_GPL(hwspin_lock_request);
* Usually early board code will be calling this function in order to
* reserve specific hwspinlock ids for predefined purposes.
*
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context (simply because there is no use case for
- * that yet).
+ * Should be called from a process context (might sleep)
*
* Returns the address of the assigned hwspinlock, or NULL on error
*/
@@ -456,7 +507,7 @@ struct hwspinlock *hwspin_lock_request_specific(unsigned int id)
struct hwspinlock *hwlock;
int ret;
- spin_lock(&hwspinlock_tree_lock);
+ mutex_lock(&hwspinlock_tree_lock);
/* make sure this hwspinlock exists */
hwlock = radix_tree_lookup(&hwspinlock_tree, id);
@@ -466,7 +517,7 @@ struct hwspinlock *hwspin_lock_request_specific(unsigned int id)
}
/* sanity check (this shouldn't happen) */
- WARN_ON(hwlock->id != id);
+ WARN_ON(hwlock_to_id(hwlock) != id);
/* make sure this hwspinlock is unused */
ret = radix_tree_tag_get(&hwspinlock_tree, id, HWSPINLOCK_UNUSED);
@@ -482,7 +533,7 @@ struct hwspinlock *hwspin_lock_request_specific(unsigned int id)
hwlock = NULL;
out:
- spin_unlock(&hwspinlock_tree_lock);
+ mutex_unlock(&hwspinlock_tree_lock);
return hwlock;
}
EXPORT_SYMBOL_GPL(hwspin_lock_request_specific);
@@ -495,14 +546,13 @@ EXPORT_SYMBOL_GPL(hwspin_lock_request_specific);
* Should only be called with an @hwlock that was retrieved from
* an earlier call to omap_hwspin_lock_request{_specific}.
*
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context (simply because there is no use case for
- * that yet).
+ * Should be called from a process context (might sleep)
*
* Returns 0 on success, or an appropriate error code on failure
*/
int hwspin_lock_free(struct hwspinlock *hwlock)
{
+ struct device *dev = hwlock->bank->dev;
struct hwspinlock *tmp;
int ret;
@@ -511,34 +561,34 @@ int hwspin_lock_free(struct hwspinlock *hwlock)
return -EINVAL;
}
- spin_lock(&hwspinlock_tree_lock);
+ mutex_lock(&hwspinlock_tree_lock);
/* make sure the hwspinlock is used */
- ret = radix_tree_tag_get(&hwspinlock_tree, hwlock->id,
+ ret = radix_tree_tag_get(&hwspinlock_tree, hwlock_to_id(hwlock),
HWSPINLOCK_UNUSED);
This diff is incomplete. Download the complete patch.
drivers/hwspinlock/hwspinlock_internal.h
View fileThis diff is incomplete. Download the complete patch.
drivers/hwspinlock/omap_hwspinlock.c
View fileThis diff is incomplete. Download the complete patch.
drivers/hwspinlock/u8500_hsem.c
View fileThis diff is incomplete. Download the complete patch.
drivers/mmc/host/omap_hsmmc.c
View fileThis diff is incomplete. Download the complete patch.
include/linux/hwspinlock.h
View fileThis diff is incomplete. Download the complete patch.