[PATCH v4 6/7] OMAP2+: clockdomain: Add per clkdm lock to prevent concurrent state programming
Benoit Cousson
b-cousson at ti.com
Fri Jul 1 17:27:05 EDT 2011
From: Rajendra Nayak <rnayak at ti.com>
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 <rnayak at ti.com>
Signed-off-by: Benoit Cousson <b-cousson at ti.com>
Cc: Paul Walmsley <paul at pwsan.com>
---
arch/arm/mach-omap2/clockdomain.c | 42 ++++++++++++++++++++++++++--
arch/arm/mach-omap2/clockdomain.h | 2 +
arch/arm/mach-omap2/clockdomain2xxx_3xxx.c | 6 ++-
arch/arm/mach-omap2/clockdomain44xx.c | 13 ++------
4 files changed, 49 insertions(+), 14 deletions(-)
diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c
index 10f6bd2..cc2e495 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;
@@ -704,7 +709,10 @@ int clkdm_sleep(struct clockdomain *clkdm)
pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name);
- return arch_clkdm->clkdm_sleep(clkdm);
+ spin_lock_irqsave(&clkdm->lock, flags);
+ ret = arch_clkdm->clkdm_sleep(clkdm);
+ spin_unlock_irqrestore(&clkdm->lock, flags);
+ return ret;
}
/**
@@ -718,6 +726,9 @@ int clkdm_sleep(struct clockdomain *clkdm)
*/
int clkdm_wakeup(struct clockdomain *clkdm)
{
+ int ret;
+ unsigned long flags;
+
if (!clkdm)
return -EINVAL;
@@ -732,7 +743,10 @@ int clkdm_wakeup(struct clockdomain *clkdm)
pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name);
- return arch_clkdm->clkdm_wakeup(clkdm);
+ spin_lock_irqsave(&clkdm->lock, flags);
+ ret = arch_clkdm->clkdm_wakeup(clkdm);
+ spin_unlock_irqrestore(&clkdm->lock, flags);
+ return ret;
}
/**
@@ -747,6 +761,8 @@ int clkdm_wakeup(struct clockdomain *clkdm)
*/
void clkdm_allow_idle(struct clockdomain *clkdm)
{
+ unsigned long flags;
+
if (!clkdm)
return;
@@ -762,8 +778,10 @@ 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);
arch_clkdm->clkdm_allow_idle(clkdm);
pwrdm_clkdm_state_switch(clkdm);
+ spin_unlock_irqrestore(&clkdm->lock, flags);
}
/**
@@ -777,6 +795,8 @@ void clkdm_allow_idle(struct clockdomain *clkdm)
*/
void clkdm_deny_idle(struct clockdomain *clkdm)
{
+ unsigned long flags;
+
if (!clkdm)
return;
@@ -792,7 +812,9 @@ 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);
arch_clkdm->clkdm_deny_idle(clkdm);
+ spin_unlock_irqrestore(&clkdm->lock, flags);
}
/**
@@ -805,6 +827,9 @@ void clkdm_deny_idle(struct clockdomain *clkdm)
*/
int clkdm_allows_idle(struct clockdomain *clkdm)
{
+ int ret;
+ unsigned long flags;
+
if (!clkdm)
return -EINVAL;
@@ -813,7 +838,10 @@ int clkdm_allows_idle(struct clockdomain *clkdm)
pr_debug("clockdomain: reading idle state for %s\n", clkdm->name);
- return arch_clkdm->clkdm_allows_idle(clkdm);
+ spin_lock_irqsave(&clkdm->lock, flags);
+ ret = arch_clkdm->clkdm_allows_idle(clkdm);
+ spin_unlock_irqrestore(&clkdm->lock, flags);
+ return ret;
}
@@ -821,6 +849,8 @@ int clkdm_allows_idle(struct clockdomain *clkdm)
static int _clkdm_clk_hwmod_enable(struct clockdomain *clkdm)
{
+ unsigned long flags;
+
if (!clkdm || !arch_clkdm || !arch_clkdm->clkdm_clk_enable)
return -EINVAL;
@@ -832,9 +862,11 @@ 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);
@@ -843,6 +875,8 @@ 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;
@@ -854,8 +888,10 @@ 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 8f0a7d6..b51f558 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 <linux/init.h>
+#include <linux/spinlock.h>
#include "powerdomain.h"
#include <plat/clock.h>
@@ -123,6 +124,7 @@ 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 81f3e46..d94a121 100644
--- a/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c
+++ b/arch/arm/mach-omap2/clockdomain2xxx_3xxx.c
@@ -193,7 +193,8 @@ 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;
@@ -215,7 +216,8 @@ 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 1599b18..3192a5e 100644
--- a/arch/arm/mach-omap2/clockdomain44xx.c
+++ b/arch/arm/mach-omap2/clockdomain44xx.c
@@ -101,13 +101,8 @@ static int omap4_clkdm_allows_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;
}
@@ -119,8 +114,8 @@ 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;
}
--
1.7.0.4
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