From 12b1fdb45c2594070bb36e39cd89a33547aad8fb Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Tue, 21 Sep 2010 10:34:09 -0600 Subject: [PATCH] OMAP: hwmod: separate list locking and hwmod hardware locking Currently omap_hwmod_mutex is being used to protect both the list access/modification and concurrent access to hwmod functions. This patch separates these two types of locking. First, omap_hwmod_mutex is used only to protect access and modification of omap_hwmod_list. Also cleaned up some comments referring to this mutex that are no longer needed. Then, for protecting concurrent access to hwmod functions, use a per-hwmod mutex. This protects concurrent access to a single hwmod, but would allow concurrent access to different hwmods. Signed-off-by: Kevin Hilman [paul@pwsan.com: added structure documentation; changed mutex variable name] Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/omap_hwmod.c | 62 ++++++++++---------- arch/arm/plat-omap/include/plat/omap_hwmod.h | 3 + 2 files changed, 33 insertions(+), 32 deletions(-) diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c index 100115ff1d96..3084409ad1dc 100644 --- a/arch/arm/mach-omap2/omap_hwmod.c +++ b/arch/arm/mach-omap2/omap_hwmod.c @@ -767,10 +767,10 @@ static struct omap_hwmod *_lookup(const char *name) * @data: not used; pass NULL * * Called by omap_hwmod_late_init() (after omap2_clk_init()). - * Resolves all clock names embedded in the hwmod. Must be called - * with omap_hwmod_mutex held. Returns -EINVAL if the omap_hwmod - * has not yet been registered or if the clocks have already been - * initialized, 0 on success, or a non-zero error on failure. + * Resolves all clock names embedded in the hwmod. Returns -EINVAL if + * the omap_hwmod has not yet been registered or if the clocks have + * already been initialized, 0 on success, or a non-zero error on + * failure. */ static int _init_clocks(struct omap_hwmod *oh, void *data) { @@ -838,10 +838,9 @@ static int _wait_target_ready(struct omap_hwmod *oh) * @oh: struct omap_hwmod * * * Resets an omap_hwmod @oh via the OCP_SYSCONFIG bit. hwmod must be - * enabled for this to work. Must be called with omap_hwmod_mutex - * held. Returns -EINVAL if the hwmod cannot be reset this way or if - * the hwmod is in the wrong state, -ETIMEDOUT if the module did not - * reset in time, or 0 upon success. + * enabled for this to work. Returns -EINVAL if the hwmod cannot be + * reset this way or if the hwmod is in the wrong state, -ETIMEDOUT if + * the module did not reset in time, or 0 upon success. */ static int _reset(struct omap_hwmod *oh) { @@ -891,9 +890,8 @@ static int _reset(struct omap_hwmod *oh) * @oh: struct omap_hwmod * * * Enables an omap_hwmod @oh such that the MPU can access the hwmod's - * register target. Must be called with omap_hwmod_mutex held. - * Returns -EINVAL if the hwmod is in the wrong state or passes along - * the return value of _wait_target_ready(). + * register target. Returns -EINVAL if the hwmod is in the wrong + * state or passes along the return value of _wait_target_ready(). */ int _omap_hwmod_enable(struct omap_hwmod *oh) { @@ -1004,11 +1002,10 @@ static int _shutdown(struct omap_hwmod *oh) * @skip_setup_idle_p: do not idle hwmods at the end of the fn if 1 * * Writes the CLOCKACTIVITY bits @clockact to the hwmod @oh - * OCP_SYSCONFIG register. Must be called with omap_hwmod_mutex held. - * @skip_setup_idle is intended to be used on a system that will not - * call omap_hwmod_enable() to enable devices (e.g., a system without - * PM runtime). Returns -EINVAL if the hwmod is in the wrong state or - * returns 0. + * OCP_SYSCONFIG register. @skip_setup_idle is intended to be used on + * a system that will not call omap_hwmod_enable() to enable devices + * (e.g., a system without PM runtime). Returns -EINVAL if the hwmod + * is in the wrong state or returns 0. */ static int _setup(struct omap_hwmod *oh, void *data) { @@ -1038,6 +1035,7 @@ static int _setup(struct omap_hwmod *oh, void *data) } } + mutex_init(&oh->_mutex); oh->_state = _HWMOD_STATE_INITIALIZED; r = _omap_hwmod_enable(oh); @@ -1323,9 +1321,9 @@ int omap_hwmod_enable(struct omap_hwmod *oh) if (!oh) return -EINVAL; - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); r = _omap_hwmod_enable(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return r; } @@ -1343,9 +1341,9 @@ int omap_hwmod_idle(struct omap_hwmod *oh) if (!oh) return -EINVAL; - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); _omap_hwmod_idle(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return 0; } @@ -1363,9 +1361,9 @@ int omap_hwmod_shutdown(struct omap_hwmod *oh) if (!oh) return -EINVAL; - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); _shutdown(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return 0; } @@ -1378,9 +1376,9 @@ int omap_hwmod_shutdown(struct omap_hwmod *oh) */ int omap_hwmod_enable_clocks(struct omap_hwmod *oh) { - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); _enable_clocks(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return 0; } @@ -1393,9 +1391,9 @@ int omap_hwmod_enable_clocks(struct omap_hwmod *oh) */ int omap_hwmod_disable_clocks(struct omap_hwmod *oh) { - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); _disable_clocks(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return 0; } @@ -1443,9 +1441,9 @@ int omap_hwmod_reset(struct omap_hwmod *oh) if (!oh) return -EINVAL; - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); r = _reset(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return r; } @@ -1646,9 +1644,9 @@ int omap_hwmod_enable_wakeup(struct omap_hwmod *oh) !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP)) return -EINVAL; - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); _enable_wakeup(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return 0; } @@ -1671,9 +1669,9 @@ int omap_hwmod_disable_wakeup(struct omap_hwmod *oh) !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP)) return -EINVAL; - mutex_lock(&omap_hwmod_mutex); + mutex_lock(&oh->_mutex); _disable_wakeup(oh); - mutex_unlock(&omap_hwmod_mutex); + mutex_unlock(&oh->_mutex); return 0; } diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h index 5506d80d94b9..03350bac01d8 100644 --- a/arch/arm/plat-omap/include/plat/omap_hwmod.h +++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h @@ -35,6 +35,7 @@ #include #include #include +#include #include struct omap_device; @@ -433,6 +434,7 @@ struct omap_hwmod_class { * @_state: internal-use hwmod state * @flags: hwmod flags (documented below) * @omap_chip: OMAP chips this hwmod is present on + * @_mutex: mutex serializing operations on this hwmod * @node: list node for hwmod list (internal use) * * @main_clk refers to this module's "main clock," which for our @@ -461,6 +463,7 @@ struct omap_hwmod { void *dev_attr; u32 _sysc_cache; void __iomem *_mpu_rt_va; + struct mutex _mutex; struct list_head node; u16 flags; u8 _mpu_port_index; -- GitLab