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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock

Browse Source 
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock:
  hwspinlock: add MAINTAINERS entries
  hwspinlock/omap: omap_hwspinlock_remove should be __devexit
  hwspinlock/u8500: add hwspinlock driver
  hwspinlock/core: register a bank of hwspinlocks in a single API call
  hwspinlock/core: remove stubs for register/unregister
  hwspinlock/core: use a mutex to protect the radix tree
  hwspinlock/core/omap: fix id issues on multiple hwspinlock devices
  hwspinlock/omap: simplify allocation scheme
  hwspinlock/core: simplify 'owner' handling
  hwspinlock/core: simplify Kconfig

Fix up trivial conflicts (addition of omap_hwspinlock_pdata, removal of
omap_spinlock_latency) in arch/arm/mach-omap2/hwspinlock.c

Also, do an "evil merge" to fix a compile error in omap_hsmmc.c which
for some reason was reported in the same email thread as the "please
pull hwspinlock changes".
This commit is contained in:
Linus Torvalds 2011-11-03 08:05:35 -07:00
commit 3f8ddb032a
11 changed files with 518 additions and 228 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
Documentation/hwspinlock.txt
View File

@ -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;
spinlock_t lock;
struct module *owner;
int base_id;
int num_locks;
struct hwspinlock lock[0];
};
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.
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;
void *priv;
};
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

14
MAINTAINERS
View File

@ -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 <ohad@wizery.com>
S: Maintained
F: Documentation/hwspinlock.txt
F: drivers/hwspinlock/hwspinlock_*
F: include/linux/hwspinlock.h
HARMONY SOUND DRIVER
M: Kyle McMartin <kyle@mcmartin.ca>
L: linux-parisc@vger.kernel.org
@ -4714,6 +4721,13 @@ S: Maintained
F: drivers/video/omap2/
F: Documentation/arm/OMAP/DSS
OMAP HARDWARE SPINLOCK SUPPORT
M: Ohad Ben-Cohen <ohad@wizery.com>
L: linux-omap@vger.kernel.org
S: Maintained
F: drivers/hwspinlock/omap_hwspinlock.c
F: arch/arm/mach-omap2/hwspinlock.c
OMAP MMC SUPPORT
M: Jarkko Lavinen <jarkko.lavinen@nokia.com>
L: linux-omap@vger.kernel.org

9
arch/arm/mach-omap2/hwspinlock.c
View File

@ -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);

27
drivers/hwspinlock/Kconfig
View File

@ -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

1
drivers/hwspinlock/Makefile
View File

@ -4,3 +4,4 @@
obj-$(CONFIG_HWSPINLOCK) += hwspinlock_core.o
obj-$(CONFIG_HWSPINLOCK_OMAP) += omap_hwspinlock.o
obj-$(CONFIG_HSEM_U8500) += u8500_hsem.o

206
drivers/hwspinlock/hwspinlock_core.c
View File

@ -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;
mutex_lock(&hwspinlock_tree_lock);
ret = radix_tree_insert(&hwspinlock_tree, id, hwlock);
if (ret) {
if (ret == -EEXIST)
pr_err("hwspinlock id %d already exists!\n", id);
goto out;
}
spin_lock_init(&hwlock->lock);
spin_lock(&hwspinlock_tree_lock);
ret = radix_tree_insert(&hwspinlock_tree, hwlock->id, hwlock);
if (ret)
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);
if (ret == 1) {
dev_err(hwlock->dev, "%s: hwlock is already free\n", __func__);
dev_err(dev, "%s: hwlock is already free\n", __func__);
dump_stack();
ret = -EINVAL;
goto out;
}
/* notify the underlying device that power is not needed */
ret = pm_runtime_put(hwlock->dev);
ret = pm_runtime_put(dev);
if (ret < 0)
goto out;
/* mark this hwspinlock as available */
tmp = radix_tree_tag_set(&hwspinlock_tree, hwlock->id,
tmp = radix_tree_tag_set(&hwspinlock_tree, hwlock_to_id(hwlock),
HWSPINLOCK_UNUSED);
/* sanity check (this shouldn't happen) */
WARN_ON(tmp != hwlock);
module_put(hwlock->owner);
module_put(dev->driver->owner);
out:
spin_unlock(&hwspinlock_tree_lock);
mutex_unlock(&hwspinlock_tree_lock);
return ret;
}
EXPORT_SYMBOL_GPL(hwspin_lock_free);

42
drivers/hwspinlock/hwspinlock_internal.h
View File

@ -21,6 +21,8 @@
#include <linux/spinlock.h>
#include <linux/device.h>
struct hwspinlock_device;
/**
* struct hwspinlock_ops - platform-specific hwspinlock handlers
*
@ -39,23 +41,37 @@ struct hwspinlock_ops {
/**
* struct hwspinlock - this struct represents a single hwspinlock instance
*
* @dev: underlying device, will be used to invoke runtime PM api
* @ops: platform-specific hwspinlock handlers
* @id: a global, unique, system-wide, index of the lock.
* @bank: the hwspinlock_device structure which owns this lock
* @lock: initialized and used by hwspinlock core
* @owner: underlying implementation module, used to maintain module ref count
*
* Note: currently simplicity was opted for, but later we can squeeze some
* memory bytes by grouping the dev, ops and owner members in a single
* per-platform struct, and have all hwspinlocks point at it.
* @priv: private data, owned by the underlying platform-specific hwspinlock drv
*/
struct hwspinlock {
struct device *dev;
const struct hwspinlock_ops *ops;
int id;
struct hwspinlock_device *bank;
spinlock_t lock;
struct module *owner;
void *priv;
};
/**
* 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_device {
struct device *dev;
const struct hwspinlock_ops *ops;
int base_id;
int num_locks;
struct hwspinlock lock[0];
};
static inline int hwlock_to_id(struct hwspinlock *hwlock)
{
int local_id = hwlock - &hwlock->bank->lock[0];
return hwlock->bank->base_id + local_id;
}
#endif /* __HWSPINLOCK_HWSPINLOCK_H */

125
drivers/hwspinlock/omap_hwspinlock.c
View File

@ -41,33 +41,20 @@
#define SPINLOCK_NOTTAKEN (0) /* free */
#define SPINLOCK_TAKEN (1) /* locked */
#define to_omap_hwspinlock(lock) \
container_of(lock, struct omap_hwspinlock, lock)
struct omap_hwspinlock {
struct hwspinlock lock;
void __iomem *addr;
};
struct omap_hwspinlock_state {
int num_locks; /* Total number of locks in system */
void __iomem *io_base; /* Mapped base address */
};
static int omap_hwspinlock_trylock(struct hwspinlock *lock)
{
struct omap_hwspinlock *omap_lock = to_omap_hwspinlock(lock);
void __iomem *lock_addr = lock->priv;
/* attempt to acquire the lock by reading its value */
return (SPINLOCK_NOTTAKEN == readl(omap_lock->addr));
return (SPINLOCK_NOTTAKEN == readl(lock_addr));
}
static void omap_hwspinlock_unlock(struct hwspinlock *lock)
{
struct omap_hwspinlock *omap_lock = to_omap_hwspinlock(lock);
void __iomem *lock_addr = lock->priv;
/* release the lock by writing 0 to it */
writel(SPINLOCK_NOTTAKEN, omap_lock->addr);
writel(SPINLOCK_NOTTAKEN, lock_addr);
}
/*
@ -93,26 +80,23 @@ static const struct hwspinlock_ops omap_hwspinlock_ops = {
static int __devinit omap_hwspinlock_probe(struct platform_device *pdev)
{
struct omap_hwspinlock *omap_lock;
struct omap_hwspinlock_state *state;
struct hwspinlock *lock;
struct hwspinlock_pdata *pdata = pdev->dev.platform_data;
struct hwspinlock_device *bank;
struct hwspinlock *hwlock;
struct resource *res;
void __iomem *io_base;
int i, ret;
int num_locks, i, ret;
if (!pdata)
return -ENODEV;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
state = kzalloc(sizeof(*state), GFP_KERNEL);
if (!state)
return -ENOMEM;
io_base = ioremap(res->start, resource_size(res));
if (!io_base) {
ret = -ENOMEM;
goto free_state;
}
if (!io_base)
return -ENOMEM;
/* Determine number of locks */
i = readl(io_base + SYSSTATUS_OFFSET);
@ -124,10 +108,18 @@ static int __devinit omap_hwspinlock_probe(struct platform_device *pdev)
goto iounmap_base;
}
state->num_locks = i * 32;
state->io_base = io_base;
num_locks = i * 32; /* actual number of locks in this device */
platform_set_drvdata(pdev, state);
bank = kzalloc(sizeof(*bank) + num_locks * sizeof(*hwlock), GFP_KERNEL);
if (!bank) {
ret = -ENOMEM;
goto iounmap_base;
}
platform_set_drvdata(pdev, bank);
for (i = 0, hwlock = &bank->lock[0]; i < num_locks; i++, hwlock++)
hwlock->priv = io_base + LOCK_BASE_OFFSET + sizeof(u32) * i;
/*
* runtime PM will make sure the clock of this module is
@ -135,79 +127,46 @@ static int __devinit omap_hwspinlock_probe(struct platform_device *pdev)
*/
pm_runtime_enable(&pdev->dev);
for (i = 0; i < state->num_locks; i++) {
omap_lock = kzalloc(sizeof(*omap_lock), GFP_KERNEL);
if (!omap_lock) {
ret = -ENOMEM;
goto free_locks;
}
omap_lock->lock.dev = &pdev->dev;
omap_lock->lock.owner = THIS_MODULE;
omap_lock->lock.id = i;
omap_lock->lock.ops = &omap_hwspinlock_ops;
omap_lock->addr = io_base + LOCK_BASE_OFFSET + sizeof(u32) * i;
ret = hwspin_lock_register(&omap_lock->lock);
if (ret) {
kfree(omap_lock);
goto free_locks;
}
}
ret = hwspin_lock_register(bank, &pdev->dev, &omap_hwspinlock_ops,
pdata->base_id, num_locks);
if (ret)
goto reg_fail;
return 0;
free_locks:
while (--i >= 0) {
lock = hwspin_lock_unregister(i);
/* this should't happen, but let's give our best effort */
if (!lock) {
dev_err(&pdev->dev, "%s: cleanups failed\n", __func__);
continue;
}
omap_lock = to_omap_hwspinlock(lock);
kfree(omap_lock);
}
reg_fail:
pm_runtime_disable(&pdev->dev);
kfree(bank);
iounmap_base:
iounmap(io_base);
free_state:
kfree(state);
return ret;
}
static int omap_hwspinlock_remove(struct platform_device *pdev)
static int __devexit omap_hwspinlock_remove(struct platform_device *pdev)
{
struct omap_hwspinlock_state *state = platform_get_drvdata(pdev);
struct hwspinlock *lock;
struct omap_hwspinlock *omap_lock;
int i;
struct hwspinlock_device *bank = platform_get_drvdata(pdev);
void __iomem *io_base = bank->lock[0].priv - LOCK_BASE_OFFSET;
int ret;
for (i = 0; i < state->num_locks; i++) {
lock = hwspin_lock_unregister(i);
/* this shouldn't happen at this point. if it does, at least
* don't continue with the remove */
if (!lock) {
dev_err(&pdev->dev, "%s: failed on %d\n", __func__, i);
return -EBUSY;
}
omap_lock = to_omap_hwspinlock(lock);
kfree(omap_lock);
ret = hwspin_lock_unregister(bank);
if (ret) {
dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
return ret;
}
pm_runtime_disable(&pdev->dev);
iounmap(state->io_base);
kfree(state);
iounmap(io_base);
kfree(bank);
return 0;
}
static struct platform_driver omap_hwspinlock_driver = {
.probe = omap_hwspinlock_probe,
.remove = omap_hwspinlock_remove,
.remove = __devexit_p(omap_hwspinlock_remove),
.driver = {
.name = "omap_hwspinlock",
.owner = THIS_MODULE,
},
};

198
drivers/hwspinlock/u8500_hsem.c Normal file
View File

@ -0,0 +1,198 @@
/*
* u8500 HWSEM driver
*
* Copyright (C) 2010-2011 ST-Ericsson
*
* Implements u8500 semaphore handling for protocol 1, no interrupts.
*
* Author: Mathieu Poirier <mathieu.poirier@linaro.org>
* Heavily borrowed from the work of :
* Simon Que <sque@ti.com>
* Hari Kanigeri <h-kanigeri2@ti.com>
* Ohad Ben-Cohen <ohad@wizery.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/hwspinlock.h>
#include <linux/platform_device.h>
#include "hwspinlock_internal.h"
/*
* Implementation of STE's HSem protocol 1 without interrutps.
* The only masterID we allow is '0x01' to force people to use
* HSems for synchronisation between processors rather than processes
* on the ARM core.
*/
#define U8500_MAX_SEMAPHORE 32 /* a total of 32 semaphore */
#define RESET_SEMAPHORE (0) /* free */
/*
* CPU ID for master running u8500 kernel.
* Hswpinlocks should only be used to synchonise operations
* between the Cortex A9 core and the other CPUs. Hence
* forcing the masterID to a preset value.
*/
#define HSEM_MASTER_ID 0x01
#define HSEM_REGISTER_OFFSET 0x08
#define HSEM_CTRL_REG 0x00
#define HSEM_ICRALL 0x90
#define HSEM_PROTOCOL_1 0x01
static int u8500_hsem_trylock(struct hwspinlock *lock)
{
void __iomem *lock_addr = lock->priv;
writel(HSEM_MASTER_ID, lock_addr);
/* get only first 4 bit and compare to masterID.
* if equal, we have the semaphore, otherwise
* someone else has it.
*/
return (HSEM_MASTER_ID == (0x0F & readl(lock_addr)));
}
static void u8500_hsem_unlock(struct hwspinlock *lock)
{
void __iomem *lock_addr = lock->priv;
/* release the lock by writing 0 to it */
writel(RESET_SEMAPHORE, lock_addr);
}
/*
* u8500: what value is recommended here ?
*/
static void u8500_hsem_relax(struct hwspinlock *lock)
{
ndelay(50);
}
static const struct hwspinlock_ops u8500_hwspinlock_ops = {
.trylock = u8500_hsem_trylock,
.unlock = u8500_hsem_unlock,
.relax = u8500_hsem_relax,
};
static int __devinit u8500_hsem_probe(struct platform_device *pdev)
{
struct hwspinlock_pdata *pdata = pdev->dev.platform_data;
struct hwspinlock_device *bank;
struct hwspinlock *hwlock;
struct resource *res;
void __iomem *io_base;
int i, ret, num_locks = U8500_MAX_SEMAPHORE;
ulong val;
if (!pdata)
return -ENODEV;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
io_base = ioremap(res->start, resource_size(res));
if (!io_base) {
ret = -ENOMEM;
goto free_state;
}
/* make sure protocol 1 is selected */
val = readl(io_base + HSEM_CTRL_REG);
writel((val & ~HSEM_PROTOCOL_1), io_base + HSEM_CTRL_REG);
/* clear all interrupts */
writel(0xFFFF, io_base + HSEM_ICRALL);
bank = kzalloc(sizeof(*bank) + num_locks * sizeof(*hwlock), GFP_KERNEL);
if (!bank) {
ret = -ENOMEM;
goto iounmap_base;
}
platform_set_drvdata(pdev, bank);
for (i = 0, hwlock = &bank->lock[0]; i < num_locks; i++, hwlock++)
hwlock->priv = io_base + HSEM_REGISTER_OFFSET + sizeof(u32) * i;
/* no pm needed for HSem but required to comply with hwspilock core */
pm_runtime_enable(&pdev->dev);
ret = hwspin_lock_register(bank, &pdev->dev, &u8500_hwspinlock_ops,
pdata->base_id, num_locks);
if (ret)
goto reg_fail;
return 0;
reg_fail:
pm_runtime_disable(&pdev->dev);
kfree(bank);
iounmap_base:
iounmap(io_base);
return ret;
}
static int __devexit u8500_hsem_remove(struct platform_device *pdev)
{
struct hwspinlock_device *bank = platform_get_drvdata(pdev);
void __iomem *io_base = bank->lock[0].priv - HSEM_REGISTER_OFFSET;
int ret;
/* clear all interrupts */
writel(0xFFFF, io_base + HSEM_ICRALL);
ret = hwspin_lock_unregister(bank);
if (ret) {
dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
return ret;
}
pm_runtime_disable(&pdev->dev);
iounmap(io_base);
kfree(bank);
return 0;
}
static struct platform_driver u8500_hsem_driver = {
.probe = u8500_hsem_probe,
.remove = __devexit_p(u8500_hsem_remove),
.driver = {
.name = "u8500_hsem",
.owner = THIS_MODULE,
},
};
static int __init u8500_hsem_init(void)
{
return platform_driver_register(&u8500_hsem_driver);
}
/* board init code might need to reserve hwspinlocks for predefined purposes */
postcore_initcall(u8500_hsem_init);
static void __exit u8500_hsem_exit(void)
{
platform_driver_unregister(&u8500_hsem_driver);
}
module_exit(u8500_hsem_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Hardware Spinlock driver for u8500");
MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");

2
drivers/mmc/host/omap_hsmmc.c
View File

@ -1270,7 +1270,7 @@ static void omap_hsmmc_protect_card(struct omap_hsmmc_host *host)
}
} else {
if (!host->protect_card) {
pr_info"%s: cover is open, "
pr_info("%s: cover is open, "
"card is now inaccessible\n",
mmc_hostname(host->mmc));
host->protect_card = 1;

46
include/linux/hwspinlock.h
View File

@ -20,17 +20,49 @@
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/device.h>
/* hwspinlock mode argument */
#define HWLOCK_IRQSTATE 0x01 /* Disable interrupts, save state */
#define HWLOCK_IRQ 0x02 /* Disable interrupts, don't save state */
struct hwspinlock;
struct hwspinlock_device;
struct hwspinlock_ops;
/**
* struct hwspinlock_pdata - platform data for hwspinlock drivers
* @base_id: base id for this hwspinlock device
*
* hwspinlock devices provide system-wide hardware locks that are used
* by remote processors that have no other way to achieve synchronization.
*
* To achieve that, each physical lock must have a system-wide id number
* that is agreed upon, otherwise remote processors can't possibly assume
* they're using the same hardware lock.
*
* Usually boards have a single hwspinlock device, which provides several
* hwspinlocks, and in this case, they can be trivially numbered 0 to
* (num-of-locks - 1).
*
* In case boards have several hwspinlocks devices, a different base id
* should be used for each hwspinlock device (they can't all use 0 as
* a starting id!).
*
* This platform data structure should be used to provide the base id
* for each device (which is trivially 0 when only a single hwspinlock
* device exists). It can be shared between different platforms, hence
* its location.
*/
struct hwspinlock_pdata {
int base_id;
};
#if defined(CONFIG_HWSPINLOCK) || defined(CONFIG_HWSPINLOCK_MODULE)
int hwspin_lock_register(struct hwspinlock *lock);
struct hwspinlock *hwspin_lock_unregister(unsigned int id);
int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
const struct hwspinlock_ops *ops, int base_id, int num_locks);
int hwspin_lock_unregister(struct hwspinlock_device *bank);
struct hwspinlock *hwspin_lock_request(void);
struct hwspinlock *hwspin_lock_request_specific(unsigned int id);
int hwspin_lock_free(struct hwspinlock *hwlock);
@ -94,16 +126,6 @@ static inline int hwspin_lock_get_id(struct hwspinlock *hwlock)
return 0;
}
static inline int hwspin_lock_register(struct hwspinlock *hwlock)
{
return -ENODEV;
}
static inline struct hwspinlock *hwspin_lock_unregister(unsigned int id)
{
return NULL;
}
#endif /* !CONFIG_HWSPINLOCK */
/**