diff mbox

[v3] ARM: EXYNOS: Fix suspend/resume sequences

Message ID 1405434287-22710-1-git-send-email-t.figa@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Tomasz Figa July 15, 2014, 2:24 p.m. UTC
Due to recent consolidation of Exynos suspend and cpuidle code, some
parts of suspend and resume sequences are executed two times, once from
exynos_pm_syscore_ops and then from exynos_cpu_pm_notifier() and thus it
breaks suspend, at least on Exynos4-based boards. In addition, simple
core power down from a cpuidle driver could, in case of CPU 0 could
result in calling functions that are specific to suspend and deeper idle
states.

This patch fixes the issue by moving those operations outside the CPU PM
notifier into suspend and AFTR code paths. This leads to a bit of code
duplication, but allows additional code simplification, so in the end
more code is removed than added.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
---
 arch/arm/mach-exynos/pm.c        | 164 ++++++++++++++++++---------------------
 drivers/cpuidle/cpuidle-exynos.c |  25 +-----
 2 files changed, 80 insertions(+), 109 deletions(-)

Comments

Tomasz Figa July 15, 2014, 2:26 p.m. UTC | #1
Forgot to CC Daniel and linux-pm. Sorry for the noise.

On 15.07.2014 16:24, Tomasz Figa wrote:
> Due to recent consolidation of Exynos suspend and cpuidle code, some
> parts of suspend and resume sequences are executed two times, once from
> exynos_pm_syscore_ops and then from exynos_cpu_pm_notifier() and thus it
> breaks suspend, at least on Exynos4-based boards. In addition, simple
> core power down from a cpuidle driver could, in case of CPU 0 could
> result in calling functions that are specific to suspend and deeper idle
> states.
> 
> This patch fixes the issue by moving those operations outside the CPU PM
> notifier into suspend and AFTR code paths. This leads to a bit of code
> duplication, but allows additional code simplification, so in the end
> more code is removed than added.
> 
> Signed-off-by: Tomasz Figa <t.figa@samsung.com>
> ---
>  arch/arm/mach-exynos/pm.c        | 164 ++++++++++++++++++---------------------
>  drivers/cpuidle/cpuidle-exynos.c |  25 +-----
>  2 files changed, 80 insertions(+), 109 deletions(-)
> 
> diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
> index 202ca73..e3b04b4 100644
> --- a/arch/arm/mach-exynos/pm.c
> +++ b/arch/arm/mach-exynos/pm.c
> @@ -176,26 +176,6 @@ int exynos_cluster_power_state(int cluster)
>  #define S5P_CHECK_AFTR  0xFCBA0D10
>  #define S5P_CHECK_SLEEP 0x00000BAD
>  
> -/* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
> -static void exynos_set_wakeupmask(long mask)
> -{
> -	__raw_writel(mask, S5P_WAKEUP_MASK);
> -}
> -
> -static void exynos_cpu_set_boot_vector(long flags)
> -{
> -	__raw_writel(virt_to_phys(exynos_cpu_resume), EXYNOS_BOOT_VECTOR_ADDR);
> -	__raw_writel(flags, EXYNOS_BOOT_VECTOR_FLAG);
> -}
> -
> -void exynos_enter_aftr(void)
> -{
> -	exynos_set_wakeupmask(0x0000ff3e);
> -	exynos_cpu_set_boot_vector(S5P_CHECK_AFTR);
> -	/* Set value of power down register for aftr mode */
> -	exynos_sys_powerdown_conf(SYS_AFTR);
> -}
> -
>  /* For Cortex-A9 Diagnostic and Power control register */
>  static unsigned int save_arm_register[2];
>  
> @@ -235,6 +215,82 @@ static void exynos_cpu_restore_register(void)
>  		      : "cc");
>  }
>  
> +static void exynos_pm_central_suspend(void)
> +{
> +	unsigned long tmp;
> +
> +	/* Setting Central Sequence Register for power down mode */
> +	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
> +	tmp &= ~S5P_CENTRAL_LOWPWR_CFG;
> +	__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
> +}
> +
> +static int exynos_pm_central_resume(void)
> +{
> +	unsigned long tmp;
> +
> +	/*
> +	 * If PMU failed while entering sleep mode, WFI will be
> +	 * ignored by PMU and then exiting cpu_do_idle().
> +	 * S5P_CENTRAL_LOWPWR_CFG bit will not be set automatically
> +	 * in this situation.
> +	 */
> +	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
> +	if (!(tmp & S5P_CENTRAL_LOWPWR_CFG)) {
> +		tmp |= S5P_CENTRAL_LOWPWR_CFG;
> +		__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
> +		/* clear the wakeup state register */
> +		__raw_writel(0x0, S5P_WAKEUP_STAT);
> +		/* No need to perform below restore code */
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +/* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
> +static void exynos_set_wakeupmask(long mask)
> +{
> +	__raw_writel(mask, S5P_WAKEUP_MASK);
> +}
> +
> +static void exynos_cpu_set_boot_vector(long flags)
> +{
> +	__raw_writel(virt_to_phys(exynos_cpu_resume), EXYNOS_BOOT_VECTOR_ADDR);
> +	__raw_writel(flags, EXYNOS_BOOT_VECTOR_FLAG);
> +}
> +
> +static int exynos_aftr_finisher(unsigned long flags)
> +{
> +	exynos_set_wakeupmask(0x0000ff3e);
> +	exynos_cpu_set_boot_vector(S5P_CHECK_AFTR);
> +	/* Set value of power down register for aftr mode */
> +	exynos_sys_powerdown_conf(SYS_AFTR);
> +	cpu_do_idle();
> +
> +	return 0;
> +}
> +
> +void exynos_enter_aftr(void)
> +{
> +	cpu_pm_enter();
> +
> +	exynos_pm_central_suspend();
> +	if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9)
> +		exynos_cpu_save_register();
> +
> +	cpu_suspend(0, exynos_aftr_finisher);
> +
> +	if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9) {
> +		scu_enable(S5P_VA_SCU);
> +		exynos_cpu_restore_register();
> +	}
> +
> +	exynos_pm_central_resume();
> +
> +	cpu_pm_exit();
> +}
> +
>  static int exynos_cpu_suspend(unsigned long arg)
>  {
>  #ifdef CONFIG_CACHE_L2X0
> @@ -279,16 +335,6 @@ static void exynos_pm_prepare(void)
>  	__raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0);
>  }
>  
> -static void exynos_pm_central_suspend(void)
> -{
> -	unsigned long tmp;
> -
> -	/* Setting Central Sequence Register for power down mode */
> -	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
> -	tmp &= ~S5P_CENTRAL_LOWPWR_CFG;
> -	__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
> -}
> -
>  static int exynos_pm_suspend(void)
>  {
>  	unsigned long tmp;
> @@ -306,29 +352,6 @@ static int exynos_pm_suspend(void)
>  	return 0;
>  }
>  
> -static int exynos_pm_central_resume(void)
> -{
> -	unsigned long tmp;
> -
> -	/*
> -	 * If PMU failed while entering sleep mode, WFI will be
> -	 * ignored by PMU and then exiting cpu_do_idle().
> -	 * S5P_CENTRAL_LOWPWR_CFG bit will not be set automatically
> -	 * in this situation.
> -	 */
> -	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
> -	if (!(tmp & S5P_CENTRAL_LOWPWR_CFG)) {
> -		tmp |= S5P_CENTRAL_LOWPWR_CFG;
> -		__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
> -		/* clear the wakeup state register */
> -		__raw_writel(0x0, S5P_WAKEUP_STAT);
> -		/* No need to perform below restore code */
> -		return -1;
> -	}
> -
> -	return 0;
> -}
> -
>  static void exynos_pm_resume(void)
>  {
>  	if (exynos_pm_central_resume())
> @@ -431,45 +454,10 @@ static const struct platform_suspend_ops exynos_suspend_ops = {
>  	.valid		= suspend_valid_only_mem,
>  };
>  
> -static int exynos_cpu_pm_notifier(struct notifier_block *self,
> -				  unsigned long cmd, void *v)
> -{
> -	int cpu = smp_processor_id();
> -
> -	switch (cmd) {
> -	case CPU_PM_ENTER:
> -		if (cpu == 0) {
> -			exynos_pm_central_suspend();
> -			if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9)
> -				exynos_cpu_save_register();
> -		}
> -		break;
> -
> -	case CPU_PM_EXIT:
> -		if (cpu == 0) {
> -			if (read_cpuid_part_number() ==
> -					ARM_CPU_PART_CORTEX_A9) {
> -				scu_enable(S5P_VA_SCU);
> -				exynos_cpu_restore_register();
> -			}
> -			exynos_pm_central_resume();
> -		}
> -		break;
> -	}
> -
> -	return NOTIFY_OK;
> -}
> -
> -static struct notifier_block exynos_cpu_pm_notifier_block = {
> -	.notifier_call = exynos_cpu_pm_notifier,
> -};
> -
>  void __init exynos_pm_init(void)
>  {
>  	u32 tmp;
>  
> -	cpu_pm_register_notifier(&exynos_cpu_pm_notifier_block);
> -
>  	/* Platform-specific GIC callback */
>  	gic_arch_extn.irq_set_wake = exynos_irq_set_wake;
>  
> diff --git a/drivers/cpuidle/cpuidle-exynos.c b/drivers/cpuidle/cpuidle-exynos.c
> index 7c01512..ba9b34b 100644
> --- a/drivers/cpuidle/cpuidle-exynos.c
> +++ b/drivers/cpuidle/cpuidle-exynos.c
> @@ -20,25 +20,6 @@
>  
>  static void (*exynos_enter_aftr)(void);
>  
> -static int idle_finisher(unsigned long flags)
> -{
> -	exynos_enter_aftr();
> -	cpu_do_idle();
> -
> -	return 1;
> -}
> -
> -static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
> -				struct cpuidle_driver *drv,
> -				int index)
> -{
> -	cpu_pm_enter();
> -	cpu_suspend(0, idle_finisher);
> -	cpu_pm_exit();
> -
> -	return index;
> -}
> -
>  static int exynos_enter_lowpower(struct cpuidle_device *dev,
>  				struct cpuidle_driver *drv,
>  				int index)
> @@ -51,8 +32,10 @@ static int exynos_enter_lowpower(struct cpuidle_device *dev,
>  
>  	if (new_index == 0)
>  		return arm_cpuidle_simple_enter(dev, drv, new_index);
> -	else
> -		return exynos_enter_core0_aftr(dev, drv, new_index);
> +
> +	exynos_enter_aftr();
> +
> +	return new_index;
>  }
>  
>  static struct cpuidle_driver exynos_idle_driver = {
>
Tomasz Figa July 17, 2014, 2:42 p.m. UTC | #2
Hi Kukjin,

On 15.07.2014 16:26, Tomasz Figa wrote:
> Forgot to CC Daniel and linux-pm. Sorry for the noise.
> 
> On 15.07.2014 16:24, Tomasz Figa wrote:
>> Due to recent consolidation of Exynos suspend and cpuidle code, some
>> parts of suspend and resume sequences are executed two times, once from
>> exynos_pm_syscore_ops and then from exynos_cpu_pm_notifier() and thus it
>> breaks suspend, at least on Exynos4-based boards. In addition, simple
>> core power down from a cpuidle driver could, in case of CPU 0 could
>> result in calling functions that are specific to suspend and deeper idle
>> states.
>>
>> This patch fixes the issue by moving those operations outside the CPU PM
>> notifier into suspend and AFTR code paths. This leads to a bit of code
>> duplication, but allows additional code simplification, so in the end
>> more code is removed than added.
>>
>> Signed-off-by: Tomasz Figa <t.figa@samsung.com>
>> ---
>>  arch/arm/mach-exynos/pm.c        | 164 ++++++++++++++++++---------------------
>>  drivers/cpuidle/cpuidle-exynos.c |  25 +-----
>>  2 files changed, 80 insertions(+), 109 deletions(-)
>>

Please consider this patch for next pull request with rc fixes. It
replaces following patches posted in this thread:

[PATCH 5/6] ARM: EXYNOS: Fix suspend/resume sequencies
[PATCH v2 5/6] ARM: EXYNOS: Fix suspend/resume sequences

and also similar patch by Chander:

[PATCH 2/2] cpuidle: Exynos: fix cpuidle for all states

Best regards,
Tomasz
Tomasz Figa July 21, 2014, 10:23 a.m. UTC | #3
Hi,

On 15.07.2014 16:26, Tomasz Figa wrote:
> Forgot to CC Daniel and linux-pm. Sorry for the noise.
> 
> On 15.07.2014 16:24, Tomasz Figa wrote:
>> Due to recent consolidation of Exynos suspend and cpuidle code, some
>> parts of suspend and resume sequences are executed two times, once from
>> exynos_pm_syscore_ops and then from exynos_cpu_pm_notifier() and thus it
>> breaks suspend, at least on Exynos4-based boards. In addition, simple
>> core power down from a cpuidle driver could, in case of CPU 0 could
>> result in calling functions that are specific to suspend and deeper idle
>> states.
>>
>> This patch fixes the issue by moving those operations outside the CPU PM
>> notifier into suspend and AFTR code paths. This leads to a bit of code
>> duplication, but allows additional code simplification, so in the end
>> more code is removed than added.
>>
>> Signed-off-by: Tomasz Figa <t.figa@samsung.com>
>> ---
>>  arch/arm/mach-exynos/pm.c        | 164 ++++++++++++++++++---------------------
>>  drivers/cpuidle/cpuidle-exynos.c |  25 +-----
>>  2 files changed, 80 insertions(+), 109 deletions(-)
>>

This is an important regression fix for 3.16 and today 3.16-rc6 was
already released...

Kukjin, could you pick up this patch and few others you missed and make
sure that it is included in 3.16-rc7? If you are busy, maybe Arnd or
Olof could take them directly?

Best regards,
Tomasz
diff mbox

Patch

diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 202ca73..e3b04b4 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -176,26 +176,6 @@  int exynos_cluster_power_state(int cluster)
 #define S5P_CHECK_AFTR  0xFCBA0D10
 #define S5P_CHECK_SLEEP 0x00000BAD
 
-/* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
-static void exynos_set_wakeupmask(long mask)
-{
-	__raw_writel(mask, S5P_WAKEUP_MASK);
-}
-
-static void exynos_cpu_set_boot_vector(long flags)
-{
-	__raw_writel(virt_to_phys(exynos_cpu_resume), EXYNOS_BOOT_VECTOR_ADDR);
-	__raw_writel(flags, EXYNOS_BOOT_VECTOR_FLAG);
-}
-
-void exynos_enter_aftr(void)
-{
-	exynos_set_wakeupmask(0x0000ff3e);
-	exynos_cpu_set_boot_vector(S5P_CHECK_AFTR);
-	/* Set value of power down register for aftr mode */
-	exynos_sys_powerdown_conf(SYS_AFTR);
-}
-
 /* For Cortex-A9 Diagnostic and Power control register */
 static unsigned int save_arm_register[2];
 
@@ -235,6 +215,82 @@  static void exynos_cpu_restore_register(void)
 		      : "cc");
 }
 
+static void exynos_pm_central_suspend(void)
+{
+	unsigned long tmp;
+
+	/* Setting Central Sequence Register for power down mode */
+	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
+	tmp &= ~S5P_CENTRAL_LOWPWR_CFG;
+	__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
+}
+
+static int exynos_pm_central_resume(void)
+{
+	unsigned long tmp;
+
+	/*
+	 * If PMU failed while entering sleep mode, WFI will be
+	 * ignored by PMU and then exiting cpu_do_idle().
+	 * S5P_CENTRAL_LOWPWR_CFG bit will not be set automatically
+	 * in this situation.
+	 */
+	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
+	if (!(tmp & S5P_CENTRAL_LOWPWR_CFG)) {
+		tmp |= S5P_CENTRAL_LOWPWR_CFG;
+		__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
+		/* clear the wakeup state register */
+		__raw_writel(0x0, S5P_WAKEUP_STAT);
+		/* No need to perform below restore code */
+		return -1;
+	}
+
+	return 0;
+}
+
+/* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
+static void exynos_set_wakeupmask(long mask)
+{
+	__raw_writel(mask, S5P_WAKEUP_MASK);
+}
+
+static void exynos_cpu_set_boot_vector(long flags)
+{
+	__raw_writel(virt_to_phys(exynos_cpu_resume), EXYNOS_BOOT_VECTOR_ADDR);
+	__raw_writel(flags, EXYNOS_BOOT_VECTOR_FLAG);
+}
+
+static int exynos_aftr_finisher(unsigned long flags)
+{
+	exynos_set_wakeupmask(0x0000ff3e);
+	exynos_cpu_set_boot_vector(S5P_CHECK_AFTR);
+	/* Set value of power down register for aftr mode */
+	exynos_sys_powerdown_conf(SYS_AFTR);
+	cpu_do_idle();
+
+	return 0;
+}
+
+void exynos_enter_aftr(void)
+{
+	cpu_pm_enter();
+
+	exynos_pm_central_suspend();
+	if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9)
+		exynos_cpu_save_register();
+
+	cpu_suspend(0, exynos_aftr_finisher);
+
+	if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9) {
+		scu_enable(S5P_VA_SCU);
+		exynos_cpu_restore_register();
+	}
+
+	exynos_pm_central_resume();
+
+	cpu_pm_exit();
+}
+
 static int exynos_cpu_suspend(unsigned long arg)
 {
 #ifdef CONFIG_CACHE_L2X0
@@ -279,16 +335,6 @@  static void exynos_pm_prepare(void)
 	__raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0);
 }
 
-static void exynos_pm_central_suspend(void)
-{
-	unsigned long tmp;
-
-	/* Setting Central Sequence Register for power down mode */
-	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
-	tmp &= ~S5P_CENTRAL_LOWPWR_CFG;
-	__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
-}
-
 static int exynos_pm_suspend(void)
 {
 	unsigned long tmp;
@@ -306,29 +352,6 @@  static int exynos_pm_suspend(void)
 	return 0;
 }
 
-static int exynos_pm_central_resume(void)
-{
-	unsigned long tmp;
-
-	/*
-	 * If PMU failed while entering sleep mode, WFI will be
-	 * ignored by PMU and then exiting cpu_do_idle().
-	 * S5P_CENTRAL_LOWPWR_CFG bit will not be set automatically
-	 * in this situation.
-	 */
-	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
-	if (!(tmp & S5P_CENTRAL_LOWPWR_CFG)) {
-		tmp |= S5P_CENTRAL_LOWPWR_CFG;
-		__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
-		/* clear the wakeup state register */
-		__raw_writel(0x0, S5P_WAKEUP_STAT);
-		/* No need to perform below restore code */
-		return -1;
-	}
-
-	return 0;
-}
-
 static void exynos_pm_resume(void)
 {
 	if (exynos_pm_central_resume())
@@ -431,45 +454,10 @@  static const struct platform_suspend_ops exynos_suspend_ops = {
 	.valid		= suspend_valid_only_mem,
 };
 
-static int exynos_cpu_pm_notifier(struct notifier_block *self,
-				  unsigned long cmd, void *v)
-{
-	int cpu = smp_processor_id();
-
-	switch (cmd) {
-	case CPU_PM_ENTER:
-		if (cpu == 0) {
-			exynos_pm_central_suspend();
-			if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9)
-				exynos_cpu_save_register();
-		}
-		break;
-
-	case CPU_PM_EXIT:
-		if (cpu == 0) {
-			if (read_cpuid_part_number() ==
-					ARM_CPU_PART_CORTEX_A9) {
-				scu_enable(S5P_VA_SCU);
-				exynos_cpu_restore_register();
-			}
-			exynos_pm_central_resume();
-		}
-		break;
-	}
-
-	return NOTIFY_OK;
-}
-
-static struct notifier_block exynos_cpu_pm_notifier_block = {
-	.notifier_call = exynos_cpu_pm_notifier,
-};
-
 void __init exynos_pm_init(void)
 {
 	u32 tmp;
 
-	cpu_pm_register_notifier(&exynos_cpu_pm_notifier_block);
-
 	/* Platform-specific GIC callback */
 	gic_arch_extn.irq_set_wake = exynos_irq_set_wake;
 
diff --git a/drivers/cpuidle/cpuidle-exynos.c b/drivers/cpuidle/cpuidle-exynos.c
index 7c01512..ba9b34b 100644
--- a/drivers/cpuidle/cpuidle-exynos.c
+++ b/drivers/cpuidle/cpuidle-exynos.c
@@ -20,25 +20,6 @@ 
 
 static void (*exynos_enter_aftr)(void);
 
-static int idle_finisher(unsigned long flags)
-{
-	exynos_enter_aftr();
-	cpu_do_idle();
-
-	return 1;
-}
-
-static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
-				struct cpuidle_driver *drv,
-				int index)
-{
-	cpu_pm_enter();
-	cpu_suspend(0, idle_finisher);
-	cpu_pm_exit();
-
-	return index;
-}
-
 static int exynos_enter_lowpower(struct cpuidle_device *dev,
 				struct cpuidle_driver *drv,
 				int index)
@@ -51,8 +32,10 @@  static int exynos_enter_lowpower(struct cpuidle_device *dev,
 
 	if (new_index == 0)
 		return arm_cpuidle_simple_enter(dev, drv, new_index);
-	else
-		return exynos_enter_core0_aftr(dev, drv, new_index);
+
+	exynos_enter_aftr();
+
+	return new_index;
 }
 
 static struct cpuidle_driver exynos_idle_driver = {