diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/hwspinlock/Kconfig | 27 | ||||
| -rw-r--r-- | drivers/hwspinlock/Makefile | 1 | ||||
| -rw-r--r-- | drivers/hwspinlock/hwspinlock_core.c | 204 | ||||
| -rw-r--r-- | drivers/hwspinlock/hwspinlock_internal.h | 40 | ||||
| -rw-r--r-- | drivers/hwspinlock/omap_hwspinlock.c | 127 | ||||
| -rw-r--r-- | drivers/hwspinlock/u8500_hsem.c | 198 | ||||
| -rw-r--r-- | drivers/mmc/host/omap_hsmmc.c | 2 |
7 files changed, 416 insertions, 183 deletions
diff --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 diff --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 diff --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); 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); diff --git a/drivers/hwspinlock/hwspinlock_internal.h b/drivers/hwspinlock/hwspinlock_internal.h index 69935e6..d26f78b 100644 --- a/drivers/hwspinlock/hwspinlock_internal.h +++ b/drivers/hwspinlock/hwspinlock_internal.h @@ -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 hwspinlock_device *bank; + spinlock_t lock; + 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 id; - spinlock_t lock; - struct module *owner; + 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 */ diff --git a/drivers/hwspinlock/omap_hwspinlock.c b/drivers/hwspinlock/omap_hwspinlock.c index a8f0273..887d34e 100644 --- a/drivers/hwspinlock/omap_hwspinlock.c +++ b/drivers/hwspinlock/omap_hwspinlock.c @@ -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 */ + + bank = kzalloc(sizeof(*bank) + num_locks * sizeof(*hwlock), GFP_KERNEL); + if (!bank) { + ret = -ENOMEM; + goto iounmap_base; + } + + platform_set_drvdata(pdev, bank); - platform_set_drvdata(pdev, state); + 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; - - 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); + struct hwspinlock_device *bank = platform_get_drvdata(pdev); + void __iomem *io_base = bank->lock[0].priv - LOCK_BASE_OFFSET; + int ret; + + 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, }, }; diff --git a/drivers/hwspinlock/u8500_hsem.c b/drivers/hwspinlock/u8500_hsem.c new file mode 100644 index 0000000..143461a --- /dev/null +++ b/drivers/hwspinlock/u8500_hsem.c @@ -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>"); diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index e8ff123..101cd31 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -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; |