From 555e74ea08bfc04a0136f976cbaa200addf1ba87 Mon Sep 17 00:00:00 2001 From: Rajendra Nayak Date: Sun, 10 Jul 2011 05:56:55 -0600 Subject: OMAP2+: clockdomain: Add per clkdm lock to prevent concurrent state programming Since the clkdm state programming is now done from within the hwmod framework (which uses a per-hwmod lock) instead of the being done from the clock framework (which used a global lock), there is now a need to have per-clkdm locking to prevent races between different hwmods/modules belonging to the same clock domain concurrently programming the clkdm state. Signed-off-by: Rajendra Nayak Signed-off-by: Benoit Cousson Cc: Paul Walmsley Signed-off-by: Paul Walmsley diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c index 239b558..ab7db08 100644 --- a/arch/arm/mach-omap2/clockdomain.c +++ b/arch/arm/mach-omap2/clockdomain.c @@ -92,6 +92,8 @@ static int _clkdm_register(struct clockdomain *clkdm) pwrdm_add_clkdm(pwrdm, clkdm); + spin_lock_init(&clkdm->lock); + pr_debug("clockdomain: registered %s\n", clkdm->name); return 0; @@ -690,6 +692,9 @@ int clkdm_clear_all_sleepdeps(struct clockdomain *clkdm) */ int clkdm_sleep(struct clockdomain *clkdm) { + int ret; + unsigned long flags; + if (!clkdm) return -EINVAL; @@ -704,9 +709,11 @@ int clkdm_sleep(struct clockdomain *clkdm) pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name); + spin_lock_irqsave(&clkdm->lock, flags); clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED; - - return arch_clkdm->clkdm_sleep(clkdm); + ret = arch_clkdm->clkdm_sleep(clkdm); + spin_unlock_irqrestore(&clkdm->lock, flags); + return ret; } /** @@ -720,6 +727,9 @@ int clkdm_sleep(struct clockdomain *clkdm) */ int clkdm_wakeup(struct clockdomain *clkdm) { + int ret; + unsigned long flags; + if (!clkdm) return -EINVAL; @@ -734,9 +744,11 @@ int clkdm_wakeup(struct clockdomain *clkdm) pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name); + spin_lock_irqsave(&clkdm->lock, flags); clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED; - - return arch_clkdm->clkdm_wakeup(clkdm); + ret = arch_clkdm->clkdm_wakeup(clkdm); + spin_unlock_irqrestore(&clkdm->lock, flags); + return ret; } /** @@ -751,6 +763,8 @@ int clkdm_wakeup(struct clockdomain *clkdm) */ void clkdm_allow_idle(struct clockdomain *clkdm) { + unsigned long flags; + if (!clkdm) return; @@ -766,10 +780,11 @@ void clkdm_allow_idle(struct clockdomain *clkdm) pr_debug("clockdomain: enabling automatic idle transitions for %s\n", clkdm->name); + spin_lock_irqsave(&clkdm->lock, flags); clkdm->_flags |= _CLKDM_FLAG_HWSUP_ENABLED; - arch_clkdm->clkdm_allow_idle(clkdm); pwrdm_clkdm_state_switch(clkdm); + spin_unlock_irqrestore(&clkdm->lock, flags); } /** @@ -783,6 +798,8 @@ void clkdm_allow_idle(struct clockdomain *clkdm) */ void clkdm_deny_idle(struct clockdomain *clkdm) { + unsigned long flags; + if (!clkdm) return; @@ -798,9 +815,10 @@ void clkdm_deny_idle(struct clockdomain *clkdm) pr_debug("clockdomain: disabling automatic idle transitions for %s\n", clkdm->name); + spin_lock_irqsave(&clkdm->lock, flags); clkdm->_flags &= ~_CLKDM_FLAG_HWSUP_ENABLED; - arch_clkdm->clkdm_deny_idle(clkdm); + spin_unlock_irqrestore(&clkdm->lock, flags); } /** @@ -816,16 +834,25 @@ void clkdm_deny_idle(struct clockdomain *clkdm) */ bool clkdm_in_hwsup(struct clockdomain *clkdm) { + bool ret; + unsigned long flags; + if (!clkdm) return false; - return (clkdm->_flags & _CLKDM_FLAG_HWSUP_ENABLED) ? true : false; + spin_lock_irqsave(&clkdm->lock, flags); + ret = (clkdm->_flags & _CLKDM_FLAG_HWSUP_ENABLED) ? true : false; + spin_unlock_irqrestore(&clkdm->lock, flags); + + return ret; } /* Clockdomain-to-clock/hwmod framework interface code */ static int _clkdm_clk_hwmod_enable(struct clockdomain *clkdm) { + unsigned long flags; + if (!clkdm || !arch_clkdm || !arch_clkdm->clkdm_clk_enable) return -EINVAL; @@ -837,9 +864,11 @@ static int _clkdm_clk_hwmod_enable(struct clockdomain *clkdm) if ((atomic_inc_return(&clkdm->usecount) > 1) && autodeps) return 0; + spin_lock_irqsave(&clkdm->lock, flags); arch_clkdm->clkdm_clk_enable(clkdm); pwrdm_wait_transition(clkdm->pwrdm.ptr); pwrdm_clkdm_state_switch(clkdm); + spin_unlock_irqrestore(&clkdm->lock, flags); pr_debug("clockdomain: clkdm %s: enabled\n", clkdm->name); @@ -848,6 +877,8 @@ static int _clkdm_clk_hwmod_enable(struct clockdomain *clkdm) static int _clkdm_clk_hwmod_disable(struct clockdomain *clkdm) { + unsigned long flags; + if (!clkdm || !arch_clkdm || !arch_clkdm->clkdm_clk_disable) return -EINVAL; @@ -859,8 +890,10 @@ static int _clkdm_clk_hwmod_disable(struct clockdomain *clkdm) if (atomic_dec_return(&clkdm->usecount) > 0) return 0; + spin_lock_irqsave(&clkdm->lock, flags); arch_clkdm->clkdm_clk_disable(clkdm); pwrdm_clkdm_state_switch(clkdm); + spin_unlock_irqrestore(&clkdm->lock, flags); pr_debug("clockdomain: clkdm %s: disabled\n", clkdm->name); diff --git a/arch/arm/mach-omap2/clockdomain.h b/arch/arm/mach-omap2/clockdomain.h index 8782a5c..1e50c88 100644 --- a/arch/arm/mach-omap2/clockdomain.h +++ b/arch/arm/mach-omap2/clockdomain.h @@ -17,6 +17,7 @@ #define __ARCH_ARM_MACH_OMAP2_CLOCKDOMAIN_H #include +#include #include "powerdomain.h" #include @@ -128,6 +129,7 @@ struct clockdomain { const struct omap_chip_id omap_chip; atomic_t usecount; struct list_head node; + spinlock_t lock; }; /** diff --git a/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c b/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c index 48d0db7..f740edb 100644 --- a/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c +++ b/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c @@ -183,7 +183,8 @@ static int omap2_clkdm_clk_enable(struct clockdomain *clkdm) _clkdm_add_autodeps(clkdm); _enable_hwsup(clkdm); } else { - clkdm_wakeup(clkdm); + if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) + omap2_clkdm_wakeup(clkdm); } return 0; @@ -205,7 +206,8 @@ static int omap2_clkdm_clk_disable(struct clockdomain *clkdm) _clkdm_del_autodeps(clkdm); _enable_hwsup(clkdm); } else { - clkdm_sleep(clkdm); + if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP) + omap2_clkdm_sleep(clkdm); } return 0; diff --git a/arch/arm/mach-omap2/clockdomain44xx.c b/arch/arm/mach-omap2/clockdomain44xx.c index a1a4ecd..b43706a 100644 --- a/arch/arm/mach-omap2/clockdomain44xx.c +++ b/arch/arm/mach-omap2/clockdomain44xx.c @@ -95,13 +95,8 @@ static void omap4_clkdm_deny_idle(struct clockdomain *clkdm) static int omap4_clkdm_clk_enable(struct clockdomain *clkdm) { - bool hwsup = false; - - hwsup = omap4_cminst_is_clkdm_in_hwsup(clkdm->prcm_partition, - clkdm->cm_inst, clkdm->clkdm_offs); - - if (!hwsup) - clkdm_wakeup(clkdm); + if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) + return omap4_clkdm_wakeup(clkdm); return 0; } @@ -113,8 +108,8 @@ static int omap4_clkdm_clk_disable(struct clockdomain *clkdm) hwsup = omap4_cminst_is_clkdm_in_hwsup(clkdm->prcm_partition, clkdm->cm_inst, clkdm->clkdm_offs); - if (!hwsup) - clkdm_sleep(clkdm); + if (!hwsup && (clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) + omap4_clkdm_sleep(clkdm); return 0; } -- cgit v0.10.2