[PATCH V2 00/17] ARM: exynos: cpuidle: Move the driver to drivers/cpuidle

[PATCH V2 00/17] ARM: exynos: cpuidle: Move the driver to drivers/cpuidle

[Daniel Lezcano]

Changelog:

V2: 
	* Added comment in changelog for calls order (5/17)
	* Call the powerdown only for cpu0 in the pm notifier
	* Set the pm notifier for all boards

V1: initial post

This patchset relies on the cpm_pm notifier to initiate the powerdown sequence
operations from pm.c instead cpuidle.c. Thus the cpuidle driver is no longer
dependent from arch specific code as everything is called from the pm.c file.

The patchset applies on top of linux-samsung/for-next.

Tested on exynos4: 4210
Tested on exynos5: 5250 (without AFTR)

Daniel Lezcano (17):
  ARM: exynos: cpuidle: Prevent forward declaration
  ARM: exynos: cpuidle: use cpuidle_register
  ARM: exynos: cpuidle: change function name prefix
  ARM: exynos: cpuidle: encapsulate register access inside a function
  ARM: exynos: cpuidle: Move some code inside the idle_finisher
  ARM: exynos: cpuidle: Fix S5P_WAKEUP_STAT call
  ARM: exynos: cpuidle: Use the cpu_pm notifier
  ARM: exynos: cpuidle: Move scu_enable in the cpu_pm notifier
  ARM: exynos: cpuidle: Remove ifdef for scu_enable
  ARM: exynos: cpuidle: Move exynos_set_wakeupmask in the cpu_pm
    notifier
  ARM: exynos: cpuidle: Move the power sequence call in the cpu_pm
    notifier
  ARM: exynos: cpuidle: Move S5P_CHECK_AFTR in a header
  ARM: exynos: cpuidle: Move clock setup to pm.c
  ARM: exynos: cpuidle: Move the boot vector in pm.c
  ARM: exynos: cpuidle: Pass the AFTR callback to the platform_data
  ARM: exynos: cpuidle: Move the driver to drivers/cpuidle directory
  ARM: exynos: config: Enable cpuidle

 arch/arm/configs/exynos_defconfig |    1 +
 arch/arm/mach-exynos/Makefile     |    1 -
 arch/arm/mach-exynos/common.c     |    5 +-
 arch/arm/mach-exynos/common.h     |    1 +
 arch/arm/mach-exynos/cpuidle.c    |  256 -------------------------------------
 arch/arm/mach-exynos/pm.c         |  191 ++++++++++++++++++++++-----
 arch/arm/mach-exynos/pmu.c        |    6 +
 arch/arm/mach-exynos/regs-pmu.h   |    1 +
 drivers/cpuidle/Kconfig.arm       |    7 +
 drivers/cpuidle/Makefile          |    1 +
 drivers/cpuidle/cpuidle-exynos.c  |  102 +++++++++++++++
 11 files changed, 281 insertions(+), 291 deletions(-)
 delete mode 100644 arch/arm/mach-exynos/cpuidle.c
 create mode 100644 drivers/cpuidle/cpuidle-exynos.c

-- 
1.7.9.5

[PATCH V2 01/17] ARM: exynos: cpuidle: Prevent forward declaration

[Daniel Lezcano]

Move the structure below the 'exynos4_enter_lowpower' function so no more
need of forward declaration.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |   40 ++++++++++++++++++----------------------
 1 file changed, 18 insertions(+), 22 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index b530231..9623a05 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -59,30 +59,8 @@
 #define PWR_CTRL2_CORE2_UP_RATIO		(1 << 4)
 #define PWR_CTRL2_CORE1_UP_RATIO		(1 << 0)
 
-static int exynos4_enter_lowpower(struct cpuidle_device *dev,
-				struct cpuidle_driver *drv,
-				int index);
-
 static DEFINE_PER_CPU(struct cpuidle_device, exynos4_cpuidle_device);
 
-static struct cpuidle_driver exynos4_idle_driver = {
-	.name			= "exynos4_idle",
-	.owner			= THIS_MODULE,
-	.states = {
-		[0] = ARM_CPUIDLE_WFI_STATE,
-		[1] = {
-			.enter			= exynos4_enter_lowpower,
-			.exit_latency		= 300,
-			.target_residency	= 100000,
-			.flags			= CPUIDLE_FLAG_TIME_VALID,
-			.name			= "C1",
-			.desc			= "ARM power down",
-		},
-	},
-	.state_count = 2,
-	.safe_state_index = 0,
-};
-
 /* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
 static void exynos4_set_wakeupmask(void)
 {
@@ -213,6 +191,24 @@ static void __init exynos5_core_down_clk(void)
 	__raw_writel(tmp, EXYNOS5_PWR_CTRL2);
 }
 
+static struct cpuidle_driver exynos4_idle_driver = {
+	.name			= "exynos4_idle",
+	.owner			= THIS_MODULE,
+	.states = {
+		[0] = ARM_CPUIDLE_WFI_STATE,
+		[1] = {
+			.enter			= exynos4_enter_lowpower,
+			.exit_latency		= 300,
+			.target_residency	= 100000,
+			.flags			= CPUIDLE_FLAG_TIME_VALID,
+			.name			= "C1",
+			.desc			= "ARM power down",
+		},
+	},
+	.state_count = 2,
+	.safe_state_index = 0,
+};
+
 static int exynos_cpuidle_probe(struct platform_device *pdev)
 {
 	int cpu_id, ret;
-- 
1.7.9.5

[PATCH V2 02/17] ARM: exynos: cpuidle: use cpuidle_register

[Daniel Lezcano]

Use the cpuidle generic function 'cpuidle_register'. That saves us from some
extra lines of code and unneeded variables.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |   18 ++----------------
 1 file changed, 2 insertions(+), 16 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 9623a05..b7cd75b 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -59,8 +59,6 @@
 #define PWR_CTRL2_CORE2_UP_RATIO		(1 << 4)
 #define PWR_CTRL2_CORE1_UP_RATIO		(1 << 0)
 
-static DEFINE_PER_CPU(struct cpuidle_device, exynos4_cpuidle_device);
-
 /* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
 static void exynos4_set_wakeupmask(void)
 {
@@ -211,8 +209,7 @@ static struct cpuidle_driver exynos4_idle_driver = {
 
 static int exynos_cpuidle_probe(struct platform_device *pdev)
 {
-	int cpu_id, ret;
-	struct cpuidle_device *device;
+	int ret;
 
 	if (soc_is_exynos5250())
 		exynos5_core_down_clk();
@@ -220,23 +217,12 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
 	if (soc_is_exynos5440())
 		exynos4_idle_driver.state_count = 1;
 
-	ret = cpuidle_register_driver(&exynos4_idle_driver);
+	ret = cpuidle_register(&exynos4_idle_driver, NULL);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register cpuidle driver\n");
 		return ret;
 	}
 
-	for_each_online_cpu(cpu_id) {
-		device = &per_cpu(exynos4_cpuidle_device, cpu_id);
-		device->cpu = cpu_id;
-
-		ret = cpuidle_register_device(device);
-		if (ret) {
-			dev_err(&pdev->dev, "failed to register cpuidle device\n");
-			return ret;
-		}
-	}
-
 	return 0;
 }
 
-- 
1.7.9.5

[PATCH V2 03/17] ARM: exynos: cpuidle: change function name prefix

[Daniel Lezcano]

The driver was initially written for exynos4 but the driver is used also for
exynos5.

Change the function prefix name exynos4 -> exynos

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |   20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index b7cd75b..16e3325 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -60,7 +60,7 @@
 #define PWR_CTRL2_CORE1_UP_RATIO		(1 << 0)
 
 /* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
-static void exynos4_set_wakeupmask(void)
+static void exynos_set_wakeupmask(void)
 {
 	__raw_writel(0x0000ff3e, S5P_WAKEUP_MASK);
 }
@@ -91,13 +91,13 @@ static int idle_finisher(unsigned long flags)
 	return 1;
 }
 
-static int exynos4_enter_core0_aftr(struct cpuidle_device *dev,
+static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
 				struct cpuidle_driver *drv,
 				int index)
 {
 	unsigned long tmp;
 
-	exynos4_set_wakeupmask();
+	exynos_set_wakeupmask();
 
 	/* Set value of power down register for aftr mode */
 	exynos_sys_powerdown_conf(SYS_AFTR);
@@ -141,7 +141,7 @@ static int exynos4_enter_core0_aftr(struct cpuidle_device *dev,
 	return index;
 }
 
-static int exynos4_enter_lowpower(struct cpuidle_device *dev,
+static int exynos_enter_lowpower(struct cpuidle_device *dev,
 				struct cpuidle_driver *drv,
 				int index)
 {
@@ -154,7 +154,7 @@ static int exynos4_enter_lowpower(struct cpuidle_device *dev,
 	if (new_index == 0)
 		return arm_cpuidle_simple_enter(dev, drv, new_index);
 	else
-		return exynos4_enter_core0_aftr(dev, drv, new_index);
+		return exynos_enter_core0_aftr(dev, drv, new_index);
 }
 
 static void __init exynos5_core_down_clk(void)
@@ -189,13 +189,13 @@ static void __init exynos5_core_down_clk(void)
 	__raw_writel(tmp, EXYNOS5_PWR_CTRL2);
 }
 
-static struct cpuidle_driver exynos4_idle_driver = {
-	.name			= "exynos4_idle",
+static struct cpuidle_driver exynos_idle_driver = {
+	.name			= "exynos_idle",
 	.owner			= THIS_MODULE,
 	.states = {
 		[0] = ARM_CPUIDLE_WFI_STATE,
 		[1] = {
-			.enter			= exynos4_enter_lowpower,
+			.enter			= exynos_enter_lowpower,
 			.exit_latency		= 300,
 			.target_residency	= 100000,
 			.flags			= CPUIDLE_FLAG_TIME_VALID,
@@ -215,9 +215,9 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
 		exynos5_core_down_clk();
 
 	if (soc_is_exynos5440())
-		exynos4_idle_driver.state_count = 1;
+		exynos_idle_driver.state_count = 1;
 
-	ret = cpuidle_register(&exynos4_idle_driver, NULL);
+	ret = cpuidle_register(&exynos_idle_driver, NULL);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register cpuidle driver\n");
 		return ret;
-- 
1.7.9.5

[PATCH V2 04/17] ARM: exynos: cpuidle: encapsulate register access inside a function

[Daniel Lezcano]

That makes the code cleaner and encapsulted. The function will be reused in the
next patch.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/pm.c |   65 ++++++++++++++++++++++++++++-----------------
 1 file changed, 41 insertions(+), 24 deletions(-)

diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 15af0ce..adfdf4b 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -103,6 +103,42 @@ static int exynos_irq_set_wake(struct irq_data *data, unsigned int state)
 /* For Cortex-A9 Diagnostic and Power control register */
 static unsigned int save_arm_register[2];
 
+static void exynos_cpu_save_register(void)
+{
+	unsigned long tmp;
+
+	/* Save Power control register */
+	asm ("mrc p15, 0, %0, c15, c0, 0"
+	     : "=r" (tmp) : : "cc");
+
+	save_arm_register[0] = tmp;
+
+	/* Save Diagnostic register */
+	asm ("mrc p15, 0, %0, c15, c0, 1"
+	     : "=r" (tmp) : : "cc");
+
+	save_arm_register[1] = tmp;
+}
+
+static void exynos_cpu_restore_register(void)
+{
+	unsigned long tmp;
+
+	/* Restore Power control register */
+	tmp = save_arm_register[0];
+
+	asm volatile ("mcr p15, 0, %0, c15, c0, 0"
+		      : : "r" (tmp)
+		      : "cc");
+
+	/* Restore Diagnostic register */
+	tmp = save_arm_register[1];
+
+	asm volatile ("mcr p15, 0, %0, c15, c0, 1"
+		      : : "r" (tmp)
+		      : "cc");
+}
+
 static int exynos_cpu_suspend(unsigned long arg)
 {
 #ifdef CONFIG_CACHE_L2X0
@@ -162,17 +198,8 @@ static int exynos_pm_suspend(void)
 	tmp = (S5P_USE_STANDBY_WFI0 | S5P_USE_STANDBY_WFE0);
 	__raw_writel(tmp, S5P_CENTRAL_SEQ_OPTION);
 
-	if (!soc_is_exynos5250()) {
-		/* Save Power control register */
-		asm ("mrc p15, 0, %0, c15, c0, 0"
-		     : "=r" (tmp) : : "cc");
-		save_arm_register[0] = tmp;
-
-		/* Save Diagnostic register */
-		asm ("mrc p15, 0, %0, c15, c0, 1"
-		     : "=r" (tmp) : : "cc");
-		save_arm_register[1] = tmp;
-	}
+	if (!soc_is_exynos5250())
+		exynos_cpu_save_register();
 
 	return 0;
 }
@@ -196,19 +223,9 @@ static void exynos_pm_resume(void)
 		/* No need to perform below restore code */
 		goto early_wakeup;
 	}
-	if (!soc_is_exynos5250()) {
-		/* Restore Power control register */
-		tmp = save_arm_register[0];
-		asm volatile ("mcr p15, 0, %0, c15, c0, 0"
-			      : : "r" (tmp)
-			      : "cc");
-
-		/* Restore Diagnostic register */
-		tmp = save_arm_register[1];
-		asm volatile ("mcr p15, 0, %0, c15, c0, 1"
-			      : : "r" (tmp)
-			      : "cc");
-	}
+
+	if (!soc_is_exynos5250())
+		exynos_cpu_restore_register();
 
 	/* For release retention */
 
-- 
1.7.9.5

[PATCH V2 05/17] ARM: exynos: cpuidle: Move some code inside the idle_finisher

[Daniel Lezcano]

Move the code around to differentiate different section of code and prepare it
to be factored out in the next patches.

The call order changed but hat doesn't have a side effect because they are
independent. The important call is cpu_do_idle() which must be done the last.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |   17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 16e3325..cdfb1ae 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -87,7 +87,16 @@ static void restore_cpu_arch_register(void)
 
 static int idle_finisher(unsigned long flags)
 {
+	exynos_set_wakeupmask();
+
+	__raw_writel(virt_to_phys(s3c_cpu_resume), REG_DIRECTGO_ADDR);
+	__raw_writel(S5P_CHECK_AFTR, REG_DIRECTGO_FLAG);
+
+	/* Set value of power down register for aftr mode */
+	exynos_sys_powerdown_conf(SYS_AFTR);
+
 	cpu_do_idle();
+
 	return 1;
 }
 
@@ -97,14 +106,6 @@ static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
 {
 	unsigned long tmp;
 
-	exynos_set_wakeupmask();
-
-	/* Set value of power down register for aftr mode */
-	exynos_sys_powerdown_conf(SYS_AFTR);
-
-	__raw_writel(virt_to_phys(exynos_cpu_resume), REG_DIRECTGO_ADDR);
-	__raw_writel(S5P_CHECK_AFTR, REG_DIRECTGO_FLAG);
-
 	save_cpu_arch_register();
 
 	/* Setting Central Sequence Register for power down mode */
-- 
1.7.9.5

[PATCH V2 06/17] ARM: exynos: cpuidle: Fix S5P_WAKEUP_STAT call

[Daniel Lezcano]

This function should be called only when the powerdown sequence fails.

Even if the current code does not hurt, by moving this line, we have the same
code than the one in pm.c.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index cdfb1ae..6663349 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -134,11 +134,10 @@ static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
 	if (!(tmp & S5P_CENTRAL_LOWPWR_CFG)) {
 		tmp |= S5P_CENTRAL_LOWPWR_CFG;
 		__raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
+		/* Clear wakeup state register */
+		__raw_writel(0x0, S5P_WAKEUP_STAT);
 	}
 
-	/* Clear wakeup state register */
-	__raw_writel(0x0, S5P_WAKEUP_STAT);
-
 	return index;
 }
 
-- 
1.7.9.5

[PATCH V2 07/17] ARM: exynos: cpuidle: Use the cpu_pm notifier

[Daniel Lezcano]

Use the cpu_pm_enter/exit notifier to group some pm code inside the pm file.

The save and restore code is duplicated across pm.c and cpuidle.c. By using
the cpu_pm notifier, we can factor out the routine.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |   24 ------------------------
 arch/arm/mach-exynos/pm.c      |   29 +++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 24 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 6663349..7f1f4ef 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -65,26 +65,6 @@ static void exynos_set_wakeupmask(void)
 	__raw_writel(0x0000ff3e, S5P_WAKEUP_MASK);
 }
 
-static unsigned int g_pwr_ctrl, g_diag_reg;
-
-static void save_cpu_arch_register(void)
-{
-	/*read power control register*/
-	asm("mrc p15, 0, %0, c15, c0, 0" : "=r"(g_pwr_ctrl) : : "cc");
-	/*read diagnostic register*/
-	asm("mrc p15, 0, %0, c15, c0, 1" : "=r"(g_diag_reg) : : "cc");
-	return;
-}
-
-static void restore_cpu_arch_register(void)
-{
-	/*write power control register*/
-	asm("mcr p15, 0, %0, c15, c0, 0" : : "r"(g_pwr_ctrl) : "cc");
-	/*write diagnostic register*/
-	asm("mcr p15, 0, %0, c15, c0, 1" : : "r"(g_diag_reg) : "cc");
-	return;
-}
-
 static int idle_finisher(unsigned long flags)
 {
 	exynos_set_wakeupmask();
@@ -106,8 +86,6 @@ static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
 {
 	unsigned long tmp;
 
-	save_cpu_arch_register();
-
 	/* Setting Central Sequence Register for power down mode */
 	tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
 	tmp &= ~S5P_CENTRAL_LOWPWR_CFG;
@@ -122,8 +100,6 @@ static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
 #endif
 	cpu_pm_exit();
 
-	restore_cpu_arch_register();
-
 	/*
 	 * If PMU failed while entering sleep mode, WFI will be
 	 * ignored by PMU and then exiting cpu_do_idle().
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index adfdf4b..67d75fe 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -16,6 +16,7 @@
 #include <linux/init.h>
 #include <linux/suspend.h>
 #include <linux/syscore_ops.h>
+#include <linux/cpu_pm.h>
 #include <linux/io.h>
 #include <linux/irqchip/arm-gic.h>
 #include <linux/err.h>
@@ -321,10 +322,38 @@ 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_cpu_save_register();
+		}
+		break;
+
+	case CPU_PM_EXIT:
+		if (cpu == 0) {
+			exynos_cpu_restore_register();
+		}
+		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;
 
-- 
1.7.9.5

[PATCH V2 08/17] ARM: exynos: cpuidle: Move scu_enable in the cpu_pm notifier

[Daniel Lezcano]

We make the cpuidle code less arch dependent.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |    6 ------
 arch/arm/mach-exynos/pm.c      |    4 ++++
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 7f1f4ef..ce31004 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -18,7 +18,6 @@
 #include <linux/platform_device.h>
 
 #include <asm/proc-fns.h>
-#include <asm/smp_scu.h>
 #include <asm/suspend.h>
 #include <asm/unified.h>
 #include <asm/cpuidle.h>
@@ -93,11 +92,6 @@ static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
 
 	cpu_pm_enter();
 	cpu_suspend(0, idle_finisher);
-
-#ifdef CONFIG_SMP
-	if (!soc_is_exynos5250())
-		scu_enable(S5P_VA_SCU);
-#endif
 	cpu_pm_exit();
 
 	/*
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 67d75fe..aba577f 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -336,6 +336,10 @@ static int exynos_cpu_pm_notifier(struct notifier_block *self,
 
 	case CPU_PM_EXIT:
 		if (cpu == 0) {
+#ifdef CONFIG_SMP
+			if (!soc_is_exynos5250())
+				scu_enable(S5P_VA_SCU);
+#endif
 			exynos_cpu_restore_register();
 		}
 		break;
-- 
1.7.9.5

[PATCH V2 09/17] ARM: exynos: cpuidle: Remove ifdef for scu_enable

[Daniel Lezcano]

The scu_enable function is already a noop in the scu's header file is
CONFIG_SMP=n, so no need to use these macros in the code.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/pm.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index aba577f..9773a00 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -244,7 +244,7 @@ static void exynos_pm_resume(void)
 
 	s3c_pm_do_restore_core(exynos_core_save, ARRAY_SIZE(exynos_core_save));
 
-	if (IS_ENABLED(CONFIG_SMP) && !soc_is_exynos5250())
+	if (!soc_is_exynos5250())
 		scu_enable(S5P_VA_SCU);
 
 early_wakeup:
@@ -336,10 +336,8 @@ static int exynos_cpu_pm_notifier(struct notifier_block *self,
 
 	case CPU_PM_EXIT:
 		if (cpu == 0) {
-#ifdef CONFIG_SMP
 			if (!soc_is_exynos5250())
 				scu_enable(S5P_VA_SCU);
-#endif
 			exynos_cpu_restore_register();
 		}
 		break;
-- 
1.7.9.5

[PATCH V2 10/17] ARM: exynos: cpuidle: Move exynos_set_wakeupmask in the cpu_pm notifier

[Daniel Lezcano]

Let's encapsulate more the PM code inside the PM file by moving the
'exynos_set_wakeupmask' function inside the pm.c and the call in the cpu_pm
notifier.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |    7 -------
 arch/arm/mach-exynos/pm.c      |    7 +++++++
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index ce31004..01444ed 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -58,15 +58,8 @@
 #define PWR_CTRL2_CORE2_UP_RATIO		(1 << 4)
 #define PWR_CTRL2_CORE1_UP_RATIO		(1 << 0)
 
-/* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
-static void exynos_set_wakeupmask(void)
-{
-	__raw_writel(0x0000ff3e, S5P_WAKEUP_MASK);
-}
-
 static int idle_finisher(unsigned long flags)
 {
-	exynos_set_wakeupmask();
 
 	__raw_writel(virt_to_phys(s3c_cpu_resume), REG_DIRECTGO_ADDR);
 	__raw_writel(S5P_CHECK_AFTR, REG_DIRECTGO_FLAG);
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 9773a00..c8b3dc4 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -322,6 +322,12 @@ static const struct platform_suspend_ops exynos_suspend_ops = {
 	.valid		= suspend_valid_only_mem,
 };
 
+/* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
+static void exynos_set_wakeupmask(void)
+{
+	__raw_writel(0x0000ff3e, S5P_WAKEUP_MASK);
+}
+
 static int exynos_cpu_pm_notifier(struct notifier_block *self,
 				  unsigned long cmd, void *v)
 {
@@ -331,6 +337,7 @@ static int exynos_cpu_pm_notifier(struct notifier_block *self,
 	case CPU_PM_ENTER:
 		if (cpu == 0) {
 			exynos_cpu_save_register();
+			exynos_set_wakeupmask();
 		}
 		break;
 
-- 
1.7.9.5

[PATCH V2 11/17] ARM: exynos: cpuidle: Move the power sequence call in the cpu_pm notifier

[Daniel Lezcano]

The code to initiate and exit the powerdown sequence is the same in pm.c and
cpuidle.c.

Let's split the common part in the pm.c and reuse it from the cpu_pm notifier.

That is one more step forward to make the cpuidle driver arch indenpendant.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |   21 ---------------------
 arch/arm/mach-exynos/pm.c      |   22 ++++++++++++++++++----
 2 files changed, 18 insertions(+), 25 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 01444ed..81d7197 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -76,31 +76,10 @@ static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
 				struct cpuidle_driver *drv,
 				int index)
 {
-	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);
-
 	cpu_pm_enter();
 	cpu_suspend(0, idle_finisher);
 	cpu_pm_exit();
 
-	/*
-	 * 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 wakeup state register */
-		__raw_writel(0x0, S5P_WAKEUP_STAT);
-	}
-
 	return index;
 }
 
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index c8b3dc4..0e73591 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -184,15 +184,19 @@ static void exynos_pm_prepare(void)
 	__raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0);
 }
 
-static int exynos_pm_suspend(void)
+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;
 
 	/* Setting SEQ_OPTION register */
 
@@ -205,7 +209,7 @@ static int exynos_pm_suspend(void)
 	return 0;
 }
 
-static void exynos_pm_resume(void)
+static int exynos_pm_central_resume(void)
 {
 	unsigned long tmp;
 
@@ -222,9 +226,17 @@ static void exynos_pm_resume(void)
 		/* clear the wakeup state register */
 		__raw_writel(0x0, S5P_WAKEUP_STAT);
 		/* No need to perform below restore code */
-		goto early_wakeup;
+		return -1;
 	}
 
+	return 0;
+}
+
+static void exynos_pm_resume(void)
+{
+	if (exynos_pm_central_resume())
+		goto early_wakeup;
+
 	if (!soc_is_exynos5250())
 		exynos_cpu_restore_register();
 
@@ -336,6 +348,7 @@ static int exynos_cpu_pm_notifier(struct notifier_block *self,
 	switch (cmd) {
 	case CPU_PM_ENTER:
 		if (cpu == 0) {
+			exynos_pm_central_suspend();
 			exynos_cpu_save_register();
 			exynos_set_wakeupmask();
 		}
@@ -346,6 +359,7 @@ static int exynos_cpu_pm_notifier(struct notifier_block *self,
 			if (!soc_is_exynos5250())
 				scu_enable(S5P_VA_SCU);
 			exynos_cpu_restore_register();
+			exynos_pm_central_resume();
 		}
 		break;
 	}
-- 
1.7.9.5

[PATCH V2 12/17] ARM: exynos: cpuidle: Move S5P_CHECK_AFTR in a header

[Daniel Lezcano]

Move the S5P_CHECK_AFTR definition to the header it belongs to.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c  |    2 --
 arch/arm/mach-exynos/regs-pmu.h |    1 +
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 81d7197..cd27dbf 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -37,8 +37,6 @@
 			S5P_INFORM6 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
 			(S5P_VA_SYSRAM + 0x20) : S5P_INFORM1))
 
-#define S5P_CHECK_AFTR		0xFCBA0D10
-
 #define EXYNOS5_PWR_CTRL1			(S5P_VA_CMU + 0x01020)
 #define EXYNOS5_PWR_CTRL2			(S5P_VA_CMU + 0x01024)
 
diff --git a/arch/arm/mach-exynos/regs-pmu.h b/arch/arm/mach-exynos/regs-pmu.h
index 4f6a256..09c43c3 100644
--- a/arch/arm/mach-exynos/regs-pmu.h
+++ b/arch/arm/mach-exynos/regs-pmu.h
@@ -120,6 +120,7 @@
 #define S5P_INT_LOCAL_PWR_EN			0x7
 
 #define S5P_CHECK_SLEEP				0x00000BAD
+#define S5P_CHECK_AFTR				0xFCBA0D10
 
 /* Only for EXYNOS4210 */
 #define S5P_CMU_CLKSTOP_LCD1_LOWPWR	S5P_PMUREG(0x1154)
-- 
1.7.9.5

[PATCH V2 13/17] ARM: exynos: cpuidle: Move clock setup to pm.c

[Daniel Lezcano]

One more step is moving the clock ratio setting at idle time in pm.c

The macro names have been changed to be consistent with the other macros
name in the file.

Note, the clock divider was working only when cpuidle was enabled because it
was in its init routine. With this change, the clock divider is set in the pm's
init routine, so it will also operate when the cpuidle driver is not set, which
is good.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c  |   54 ---------------------------------------
 arch/arm/mach-exynos/pm.c       |   35 +++++++++++++++++++++++++
 arch/arm/mach-exynos/regs-pmu.h |   19 ++++++++++++++
 3 files changed, 54 insertions(+), 54 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index cd27dbf..44d169b 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -37,25 +37,6 @@
 			S5P_INFORM6 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
 			(S5P_VA_SYSRAM + 0x20) : S5P_INFORM1))
 
-#define EXYNOS5_PWR_CTRL1			(S5P_VA_CMU + 0x01020)
-#define EXYNOS5_PWR_CTRL2			(S5P_VA_CMU + 0x01024)
-
-#define PWR_CTRL1_CORE2_DOWN_RATIO		(7 << 28)
-#define PWR_CTRL1_CORE1_DOWN_RATIO		(7 << 16)
-#define PWR_CTRL1_DIV2_DOWN_EN			(1 << 9)
-#define PWR_CTRL1_DIV1_DOWN_EN			(1 << 8)
-#define PWR_CTRL1_USE_CORE1_WFE			(1 << 5)
-#define PWR_CTRL1_USE_CORE0_WFE			(1 << 4)
-#define PWR_CTRL1_USE_CORE1_WFI			(1 << 1)
-#define PWR_CTRL1_USE_CORE0_WFI			(1 << 0)
-
-#define PWR_CTRL2_DIV2_UP_EN			(1 << 25)
-#define PWR_CTRL2_DIV1_UP_EN			(1 << 24)
-#define PWR_CTRL2_DUR_STANDBY2_VAL		(1 << 16)
-#define PWR_CTRL2_DUR_STANDBY1_VAL		(1 << 8)
-#define PWR_CTRL2_CORE2_UP_RATIO		(1 << 4)
-#define PWR_CTRL2_CORE1_UP_RATIO		(1 << 0)
-
 static int idle_finisher(unsigned long flags)
 {
 
@@ -97,38 +78,6 @@ static int exynos_enter_lowpower(struct cpuidle_device *dev,
 		return exynos_enter_core0_aftr(dev, drv, new_index);
 }
 
-static void __init exynos5_core_down_clk(void)
-{
-	unsigned int tmp;
-
-	/*
-	 * Enable arm clock down (in idle) and set arm divider
-	 * ratios in WFI/WFE state.
-	 */
-	tmp = PWR_CTRL1_CORE2_DOWN_RATIO | \
-	      PWR_CTRL1_CORE1_DOWN_RATIO | \
-	      PWR_CTRL1_DIV2_DOWN_EN	 | \
-	      PWR_CTRL1_DIV1_DOWN_EN	 | \
-	      PWR_CTRL1_USE_CORE1_WFE	 | \
-	      PWR_CTRL1_USE_CORE0_WFE	 | \
-	      PWR_CTRL1_USE_CORE1_WFI	 | \
-	      PWR_CTRL1_USE_CORE0_WFI;
-	__raw_writel(tmp, EXYNOS5_PWR_CTRL1);
-
-	/*
-	 * Enable arm clock up (on exiting idle). Set arm divider
-	 * ratios when not in idle along with the standby duration
-	 * ratios.
-	 */
-	tmp = PWR_CTRL2_DIV2_UP_EN	 | \
-	      PWR_CTRL2_DIV1_UP_EN	 | \
-	      PWR_CTRL2_DUR_STANDBY2_VAL | \
-	      PWR_CTRL2_DUR_STANDBY1_VAL | \
-	      PWR_CTRL2_CORE2_UP_RATIO	 | \
-	      PWR_CTRL2_CORE1_UP_RATIO;
-	__raw_writel(tmp, EXYNOS5_PWR_CTRL2);
-}
-
 static struct cpuidle_driver exynos_idle_driver = {
 	.name			= "exynos_idle",
 	.owner			= THIS_MODULE,
@@ -151,9 +100,6 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
 {
 	int ret;
 
-	if (soc_is_exynos5250())
-		exynos5_core_down_clk();
-
 	if (soc_is_exynos5440())
 		exynos_idle_driver.state_count = 1;
 
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 0e73591..90fb692 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -140,6 +140,38 @@ static void exynos_cpu_restore_register(void)
 		      : "cc");
 }
 
+static void __init exynos5_core_down_clk(void)
+{
+	unsigned int tmp;
+
+	/*
+	 * Enable arm clock down (in idle) and set arm divider
+	 * ratios in WFI/WFE state.
+	 */
+	tmp = EXYNOS5_PWR_CTRL1_CORE2_DOWN_RATIO | \
+	      EXYNOS5_PWR_CTRL1_CORE1_DOWN_RATIO | \
+	      EXYNOS5_PWR_CTRL1_DIV2_DOWN_EN	 | \
+	      EXYNOS5_PWR_CTRL1_DIV1_DOWN_EN	 | \
+	      EXYNOS5_PWR_CTRL1_USE_CORE1_WFE	 | \
+	      EXYNOS5_PWR_CTRL1_USE_CORE0_WFE	 | \
+	      EXYNOS5_PWR_CTRL1_USE_CORE1_WFI	 | \
+	      EXYNOS5_PWR_CTRL1_USE_CORE0_WFI;
+	__raw_writel(tmp, EXYNOS5_PWR_CTRL1);
+
+	/*
+	 * Enable arm clock up (on exiting idle). Set arm divider
+	 * ratios when not in idle along with the standby duration
+	 * ratios.
+	 */
+	tmp = EXYNOS5_PWR_CTRL2_DIV2_UP_EN	 | \
+	      EXYNOS5_PWR_CTRL2_DIV1_UP_EN	 | \
+	      EXYNOS5_PWR_CTRL2_DUR_STANDBY2_VAL | \
+	      EXYNOS5_PWR_CTRL2_DUR_STANDBY1_VAL | \
+	      EXYNOS5_PWR_CTRL2_CORE2_UP_RATIO	 | \
+	      EXYNOS5_PWR_CTRL2_CORE1_UP_RATIO;
+	__raw_writel(tmp, EXYNOS5_PWR_CTRL2);
+}
+
 static int exynos_cpu_suspend(unsigned long arg)
 {
 #ifdef CONFIG_CACHE_L2X0
@@ -256,6 +288,9 @@ static void exynos_pm_resume(void)
 
 	s3c_pm_do_restore_core(exynos_core_save, ARRAY_SIZE(exynos_core_save));
 
+	if (soc_is_exynos5250())
+		exynos5_core_down_clk();
+
 	if (!soc_is_exynos5250())
 		scu_enable(S5P_VA_SCU);
 
diff --git a/arch/arm/mach-exynos/regs-pmu.h b/arch/arm/mach-exynos/regs-pmu.h
index 09c43c3..ba5f038 100644
--- a/arch/arm/mach-exynos/regs-pmu.h
+++ b/arch/arm/mach-exynos/regs-pmu.h
@@ -314,4 +314,23 @@
 
 #define EXYNOS5_OPTION_USE_RETENTION				(1 << 4)
 
+#define EXYNOS5_PWR_CTRL1			(S5P_VA_CMU + 0x01020)
+#define EXYNOS5_PWR_CTRL2			(S5P_VA_CMU + 0x01024)
+
+#define EXYNOS5_PWR_CTRL1_CORE2_DOWN_RATIO	(7 << 28)
+#define EXYNOS5_PWR_CTRL1_CORE1_DOWN_RATIO	(7 << 16)
+#define EXYNOS5_PWR_CTRL1_DIV2_DOWN_EN		(1 << 9)
+#define EXYNOS5_PWR_CTRL1_DIV1_DOWN_EN		(1 << 8)
+#define EXYNOS5_PWR_CTRL1_USE_CORE1_WFE		(1 << 5)
+#define EXYNOS5_PWR_CTRL1_USE_CORE0_WFE		(1 << 4)
+#define EXYNOS5_PWR_CTRL1_USE_CORE1_WFI		(1 << 1)
+#define EXYNOS5_PWR_CTRL1_USE_CORE0_WFI		(1 << 0)
+
+#define EXYNOS5_PWR_CTRL2_DIV2_UP_EN		(1 << 25)
+#define EXYNOS5_PWR_CTRL2_DIV1_UP_EN		(1 << 24)
+#define EXYNOS5_PWR_CTRL2_DUR_STANDBY2_VAL	(1 << 16)
+#define EXYNOS5_PWR_CTRL2_DUR_STANDBY1_VAL	(1 << 8)
+#define EXYNOS5_PWR_CTRL2_CORE2_UP_RATIO	(1 << 4)
+#define EXYNOS5_PWR_CTRL2_CORE1_UP_RATIO	(1 << 0)
+
 #endif /* __ASM_ARCH_REGS_PMU_H */
-- 
1.7.9.5

[PATCH V2 14/17] ARM: exynos: cpuidle: Move the boot vector in pm.c

[Daniel Lezcano]

As usual, move the boot vector setting in the pm.c file and use the cpu_pm
notifier to set it up.

Remove the unused headers.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/cpuidle.c |   23 -----------------------
 arch/arm/mach-exynos/pm.c      |   15 +++++++++++++++
 2 files changed, 15 insertions(+), 23 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 44d169b..4b94181 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -8,46 +8,23 @@
  * published by the Free Software Foundation.
 */
 
-#include <linux/kernel.h>
-#include <linux/init.h>
 #include <linux/cpuidle.h>
 #include <linux/cpu_pm.h>
-#include <linux/io.h>
-#include <linux/export.h>
-#include <linux/time.h>
 #include <linux/platform_device.h>
 
 #include <asm/proc-fns.h>
 #include <asm/suspend.h>
-#include <asm/unified.h>
 #include <asm/cpuidle.h>
 
 #include <plat/cpu.h>
-#include <plat/pm.h>
-
-#include <mach/map.h>
 
 #include "common.h"
-#include "regs-pmu.h"
-
-#define REG_DIRECTGO_ADDR	(samsung_rev() == EXYNOS4210_REV_1_1 ? \
-			S5P_INFORM7 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
-			(S5P_VA_SYSRAM + 0x24) : S5P_INFORM0))
-#define REG_DIRECTGO_FLAG	(samsung_rev() == EXYNOS4210_REV_1_1 ? \
-			S5P_INFORM6 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
-			(S5P_VA_SYSRAM + 0x20) : S5P_INFORM1))
 
 static int idle_finisher(unsigned long flags)
 {
-
-	__raw_writel(virt_to_phys(s3c_cpu_resume), REG_DIRECTGO_ADDR);
-	__raw_writel(S5P_CHECK_AFTR, REG_DIRECTGO_FLAG);
-
 	/* Set value of power down register for aftr mode */
 	exynos_sys_powerdown_conf(SYS_AFTR);
-
 	cpu_do_idle();
-
 	return 1;
 }
 
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 90fb692..e4ecd8c 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c
@@ -172,6 +172,20 @@ static void __init exynos5_core_down_clk(void)
 	__raw_writel(tmp, EXYNOS5_PWR_CTRL2);
 }
 
+#define EXYNOS_BOOT_VECTOR_ADDR (samsung_rev() == EXYNOS4210_REV_1_1 ? \
+			S5P_INFORM7 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
+			(S5P_VA_SYSRAM + 0x24) : S5P_INFORM0))
+
+#define EXYNOS_BOOT_VECTOR_FLAG (samsung_rev() == EXYNOS4210_REV_1_1 ? \
+			S5P_INFORM6 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
+			(S5P_VA_SYSRAM + 0x20) : S5P_INFORM1))
+
+static void exynos_cpu_set_boot_vector(void)
+{
+	__raw_writel(virt_to_phys(exynos_cpu_resume), EXYNOS_BOOT_VECTOR_ADDR);
+	__raw_writel(S5P_CHECK_AFTR, EXYNOS_BOOT_VECTOR_FLAG);
+}
+
 static int exynos_cpu_suspend(unsigned long arg)
 {
 #ifdef CONFIG_CACHE_L2X0
@@ -387,6 +401,7 @@ static int exynos_cpu_pm_notifier(struct notifier_block *self,
 			exynos_cpu_save_register();
 			exynos_set_wakeupmask();
 		}
+		exynos_cpu_set_boot_vector();
 		break;
 
 	case CPU_PM_EXIT:
-- 
1.7.9.5

[PATCH V2 15/17] ARM: exynos: cpuidle: Pass the AFTR callback to the platform_data

[Daniel Lezcano]

No more dependency on the arch code. The platform_data field is used to set the
PM callback as the other cpuidle drivers.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/common.h  |    1 +
 arch/arm/mach-exynos/cpuidle.c |    6 ++++--
 arch/arm/mach-exynos/exynos.c  |    5 +++--
 arch/arm/mach-exynos/pmu.c     |    6 ++++++
 4 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-exynos/common.h b/arch/arm/mach-exynos/common.h
index 9ef3f83..7d9432e 100644
--- a/arch/arm/mach-exynos/common.h
+++ b/arch/arm/mach-exynos/common.h
@@ -62,5 +62,6 @@ struct exynos_pmu_conf {
 };
 
 extern void exynos_sys_powerdown_conf(enum sys_powerdown mode);
+extern void exynos_sys_powerdown_aftr(void);
 
 #endif /* __ARCH_ARM_MACH_EXYNOS_COMMON_H */
diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 4b94181..149fdeb 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -18,12 +18,12 @@
 
 #include <plat/cpu.h>
 
-#include "common.h"
+static void (*exynos_aftr)(void);
 
 static int idle_finisher(unsigned long flags)
 {
 	/* Set value of power down register for aftr mode */
-	exynos_sys_powerdown_conf(SYS_AFTR);
+	exynos_aftr();
 	cpu_do_idle();
 	return 1;
 }
@@ -80,6 +80,8 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
 	if (soc_is_exynos5440())
 		exynos_idle_driver.state_count = 1;
 
+	exynos_aftr = (void *)(pdev->dev.platform_data);
+
 	ret = cpuidle_register(&exynos_idle_driver, NULL);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register cpuidle driver\n");
diff --git a/arch/arm/mach-exynos/exynos.c b/arch/arm/mach-exynos/exynos.c
index b567361..451b371 100644
--- a/arch/arm/mach-exynos/exynos.c
+++ b/arch/arm/mach-exynos/exynos.c
@@ -221,8 +221,9 @@ void exynos_restart(enum reboot_mode mode, const char *cmd)
 }
 
 static struct platform_device exynos_cpuidle = {
-	.name		= "exynos_cpuidle",
-	.id		= -1,
+	.name              = "exynos_cpuidle",
+	.dev.platform_data = exynos_sys_powerdown_aftr,
+	.id                = -1,
 };
 
 void __init exynos_cpuidle_init(void)
diff --git a/arch/arm/mach-exynos/pmu.c b/arch/arm/mach-exynos/pmu.c
index 05c7ce1..fd1ae22 100644
--- a/arch/arm/mach-exynos/pmu.c
+++ b/arch/arm/mach-exynos/pmu.c
@@ -389,6 +389,12 @@ void exynos_sys_powerdown_conf(enum sys_powerdown mode)
 	}
 }
 
+/* Set value of power down register for aftr mode */
+void exynos_sys_powerdown_aftr(void)
+{
+	exynos_sys_powerdown_conf(SYS_AFTR);
+}
+
 static int __init exynos_pmu_init(void)
 {
 	unsigned int value;
-- 
1.7.9.5

[PATCH V2 16/17] ARM: exynos: cpuidle: Move the driver to drivers/cpuidle directory

[Daniel Lezcano]

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-exynos/Makefile                      |    1 -
 drivers/cpuidle/Kconfig.arm                        |    7 +++++++
 drivers/cpuidle/Makefile                           |    1 +
 .../cpuidle.c => drivers/cpuidle/cpuidle-exynos.c  |    0
 4 files changed, 8 insertions(+), 1 deletion(-)
 rename arch/arm/mach-exynos/cpuidle.c => drivers/cpuidle/cpuidle-exynos.c (100%)

diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile
index a656dbe..21bd364 100644
--- a/arch/arm/mach-exynos/Makefile
+++ b/arch/arm/mach-exynos/Makefile
@@ -16,7 +16,6 @@ obj-$(CONFIG_ARCH_EXYNOS)	+= exynos.o
 
 obj-$(CONFIG_PM_SLEEP)		+= pm.o sleep.o
 obj-$(CONFIG_PM_GENERIC_DOMAINS) += pm_domains.o
-obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o
 
 obj-$(CONFIG_ARCH_EXYNOS)	+= pmu.o
 
diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index d988948..92f0c12 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm
@@ -44,3 +44,10 @@ config ARM_AT91_CPUIDLE
 	depends on ARCH_AT91
 	help
 	  Select this to enable cpuidle for AT91 processors
+
+config ARM_EXYNOS_CPUIDLE
+	bool "Cpu Idle Driver for the Exynos processors"
+	default y
+	depends on ARCH_EXYNOS
+	help
+	  Select this to enable cpuidle for Exynos processors
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index f71ae1b..0d1540a 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_ARM_KIRKWOOD_CPUIDLE)	+= cpuidle-kirkwood.o
 obj-$(CONFIG_ARM_ZYNQ_CPUIDLE)		+= cpuidle-zynq.o
 obj-$(CONFIG_ARM_U8500_CPUIDLE)         += cpuidle-ux500.o
 obj-$(CONFIG_ARM_AT91_CPUIDLE)          += cpuidle-at91.o
+obj-$(CONFIG_ARM_EXYNOS_CPUIDLE)        += cpuidle-exynos.o
 
 ###############################################################################
 # POWERPC drivers
diff --git a/arch/arm/mach-exynos/cpuidle.c b/drivers/cpuidle/cpuidle-exynos.c
similarity index 100%
rename from arch/arm/mach-exynos/cpuidle.c
rename to drivers/cpuidle/cpuidle-exynos.c
-- 
1.7.9.5

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Daniel Lezcano]

The cpuidle driver is broken since v3.11 and now we are at v3.14.

Default the cpuidle driver to favorize a better detection next time.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/configs/exynos_defconfig |    1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
index 4ce7b70..6ed4b34 100644
--- a/arch/arm/configs/exynos_defconfig
+++ b/arch/arm/configs/exynos_defconfig
@@ -132,3 +132,4 @@ CONFIG_DEBUG_INFO=y
 CONFIG_DEBUG_USER=y
 CONFIG_CRYPTO_SHA256=y
 CONFIG_CRC_CCITT=y
+CONFIG_CPU_IDLE=y
-- 
1.7.9.5

[PATCH V2 01/17] ARM: exynos: cpuidle: Prevent forward declaration

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:42:53 PM Daniel Lezcano wrote:
> Move the structure below the 'exynos4_enter_lowpower' function so no more
> need of forward declaration.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 02/17] ARM: exynos: cpuidle: use cpuidle_register

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:42:54 PM Daniel Lezcano wrote:
> Use the cpuidle generic function 'cpuidle_register'. That saves us from some
> extra lines of code and unneeded variables.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  arch/arm/mach-exynos/cpuidle.c |   18 ++----------------
>  1 file changed, 2 insertions(+), 16 deletions(-)
> 
> diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
> index 9623a05..b7cd75b 100644
> --- a/arch/arm/mach-exynos/cpuidle.c
> +++ b/arch/arm/mach-exynos/cpuidle.c
> @@ -59,8 +59,6 @@
>  #define PWR_CTRL2_CORE2_UP_RATIO		(1 << 4)
>  #define PWR_CTRL2_CORE1_UP_RATIO		(1 << 0)
>  
> -static DEFINE_PER_CPU(struct cpuidle_device, exynos4_cpuidle_device);
> -
>  /* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
>  static void exynos4_set_wakeupmask(void)
>  {
> @@ -211,8 +209,7 @@ static struct cpuidle_driver exynos4_idle_driver = {
>  
>  static int exynos_cpuidle_probe(struct platform_device *pdev)
>  {
> -	int cpu_id, ret;
> -	struct cpuidle_device *device;
> +	int ret;
>  
>  	if (soc_is_exynos5250())
>  		exynos5_core_down_clk();
> @@ -220,23 +217,12 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
>  	if (soc_is_exynos5440())
>  		exynos4_idle_driver.state_count = 1;
>  
> -	ret = cpuidle_register_driver(&exynos4_idle_driver);
> +	ret = cpuidle_register(&exynos4_idle_driver, NULL);
>  	if (ret) {
>  		dev_err(&pdev->dev, "failed to register cpuidle driver\n");
>  		return ret;
>  	}
>  
> -	for_each_online_cpu(cpu_id) {

cpuidle_register() does setup for_each_possible_cpu().  This is a good
thing and your patch has a nice bugfix side effect that is worth mentioning
in the patch description IMHO.

> -		device = &per_cpu(exynos4_cpuidle_device, cpu_id);
> -		device->cpu = cpu_id;
> -
> -		ret = cpuidle_register_device(device);
> -		if (ret) {
> -			dev_err(&pdev->dev, "failed to register cpuidle device\n");
> -			return ret;
> -		}
> -	}
> -
>  	return 0;
>  }

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 03/17] ARM: exynos: cpuidle: change function name prefix

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:42:55 PM Daniel Lezcano wrote:
> The driver was initially written for exynos4 but the driver is used also for
> exynos5.
> 
> Change the function prefix name exynos4 -> exynos
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 04/17] ARM: exynos: cpuidle: encapsulate register access inside a function

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:42:56 PM Daniel Lezcano wrote:
> That makes the code cleaner and encapsulted. The function will be reused in the
> next patch.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 05/17] ARM: exynos: cpuidle: Move some code inside the idle_finisher

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:42:57 PM Daniel Lezcano wrote:
> Move the code around to differentiate different section of code and prepare it
> to be factored out in the next patches.
> 
> The call order changed but hat doesn't have a side effect because they are
> independent. The important call is cpu_do_idle() which must be done the last.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 06/17] ARM: exynos: cpuidle: Fix S5P_WAKEUP_STAT call

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:42:58 PM Daniel Lezcano wrote:
> This function should be called only when the powerdown sequence fails.
> 
> Even if the current code does not hurt, by moving this line, we have the same
> code than the one in pm.c.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 07/17] ARM: exynos: cpuidle: Use the cpu_pm notifier

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:42:59 PM Daniel Lezcano wrote:
> Use the cpu_pm_enter/exit notifier to group some pm code inside the pm file.
> 
> The save and restore code is duplicated across pm.c and cpuidle.c. By using
> the cpu_pm notifier, we can factor out the routine.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Thanks for fixing Exynos5250 support in V2.

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 08/17] ARM: exynos: cpuidle: Move scu_enable in the cpu_pm notifier

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:00 PM Daniel Lezcano wrote:
> We make the cpuidle code less arch dependent.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 09/17] ARM: exynos: cpuidle: Remove ifdef for scu_enable

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:01 PM Daniel Lezcano wrote:
> The scu_enable function is already a noop in the scu's header file is
> CONFIG_SMP=n, so no need to use these macros in the code.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 10/17] ARM: exynos: cpuidle: Move exynos_set_wakeupmask in the cpu_pm notifier

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:02 PM Daniel Lezcano wrote:
> Let's encapsulate more the PM code inside the PM file by moving the
> 'exynos_set_wakeupmask' function inside the pm.c and the call in the cpu_pm
> notifier.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 11/17] ARM: exynos: cpuidle: Move the power sequence call in the cpu_pm notifier

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:03 PM Daniel Lezcano wrote:
> The code to initiate and exit the powerdown sequence is the same in pm.c and
> cpuidle.c.
> 
> Let's split the common part in the pm.c and reuse it from the cpu_pm notifier.
> 
> That is one more step forward to make the cpuidle driver arch indenpendant.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 12/17] ARM: exynos: cpuidle: Move S5P_CHECK_AFTR in a header

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:04 PM Daniel Lezcano wrote:
> Move the S5P_CHECK_AFTR definition to the header it belongs to.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 13/17] ARM: exynos: cpuidle: Move clock setup to pm.c

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:05 PM Daniel Lezcano wrote:
> One more step is moving the clock ratio setting at idle time in pm.c
> 
> The macro names have been changed to be consistent with the other macros
> name in the file.
> 
> Note, the clock divider was working only when cpuidle was enabled because it
> was in its init routine. With this change, the clock divider is set in the pm's
> init routine, so it will also operate when the cpuidle driver is not set, which
> is good.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

There was the earlier patch which was moving this code to clock driver
however it fell through cracks.  Either way is fine with me so..

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 14/17] ARM: exynos: cpuidle: Move the boot vector in pm.c

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:06 PM Daniel Lezcano wrote:
> As usual, move the boot vector setting in the pm.c file and use the cpu_pm
> notifier to set it up.
> 
> Remove the unused headers.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 15/17] ARM: exynos: cpuidle: Pass the AFTR callback to the platform_data

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:07 PM Daniel Lezcano wrote:
> No more dependency on the arch code. The platform_data field is used to set the
> PM callback as the other cpuidle drivers.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 16/17] ARM: exynos: cpuidle: Move the driver to drivers/cpuidle directory

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:08 PM Daniel Lezcano wrote:
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Bartlomiej Zolnierkiewicz]

On Friday, April 04, 2014 03:43:09 PM Daniel Lezcano wrote:
> The cpuidle driver is broken since v3.11 and now we are at v3.14.
> 
> Default the cpuidle driver to favorize a better detection next time.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  arch/arm/configs/exynos_defconfig |    1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
> index 4ce7b70..6ed4b34 100644
> --- a/arch/arm/configs/exynos_defconfig
> +++ b/arch/arm/configs/exynos_defconfig
> @@ -132,3 +132,4 @@ CONFIG_DEBUG_INFO=y
>  CONFIG_DEBUG_USER=y
>  CONFIG_CRYPTO_SHA256=y
>  CONFIG_CRC_CCITT=y
> +CONFIG_CPU_IDLE=y

Sorry but I have to NAK this change.  There are three issues with AFTR
mode that should be resolved first before this patch can be merged:

* The upstream Exynos cpuidle code lacks support for secure firmware and
  it is used on i.e. Trats2 boards (Exynos4412).  Attempts to use AFTR on
  such hardware results in oops + lockup.

  I have patches adding secure firmware support to Exynos cpuidle driver
  but they depend on Tomasz Figa's PM changes which are not yet upstream.

* Somebody needs to verify that the current Exynos cpuidle driver works
  in the AFTR mode on Exynos5420 for which support has been added recently
  (I really doubt it looking at some internal trees).

* Some of our u-boot bootloader versions are incompatible with AFTR.  We
  have observed the problem happening on Trats board (Exynos4210) on which
  it can be fixed by using the upstream u-boot version and Universal C210
  board (Exynos4210 with broken SMP support) on which there is no upstream
  u-boot available (IIRC) and because of the broken SMP support enabling
  cpuidle results in attempt to enter AFTR during boot + immediate lockup.

  I know that this is mainly our problem but the issue is widespread on
  our targets and I believe that adding some workaround for it in cpuidle
  core would be beneficial for the whole cpuidle subsystem.  Namely there
  should be some way of telling cpuidle subsystem to either disable
  particular state(s) or limit the max available state.  I think that this
  can be also useful for testing and development of other cpuidle drivers.

For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
the config option is "default y" it will be auto-enabled if there is no
entry in the defconfig)..

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Daniel Lezcano]

On 04/04/2014 06:09 PM, Bartlomiej Zolnierkiewicz wrote:
>
> On Friday, April 04, 2014 03:43:09 PM Daniel Lezcano wrote:
>> The cpuidle driver is broken since v3.11 and now we are at v3.14.
>>
>> Default the cpuidle driver to favorize a better detection next time.
>>
>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
>> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
>> ---
>>   arch/arm/configs/exynos_defconfig |    1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
>> index 4ce7b70..6ed4b34 100644
>> --- a/arch/arm/configs/exynos_defconfig
>> +++ b/arch/arm/configs/exynos_defconfig
>> @@ -132,3 +132,4 @@ CONFIG_DEBUG_INFO=y
>>   CONFIG_DEBUG_USER=y
>>   CONFIG_CRYPTO_SHA256=y
>>   CONFIG_CRC_CCITT=y
>> +CONFIG_CPU_IDLE=y
>
> Sorry but I have to NAK this change.  There are three issues with AFTR
> mode that should be resolved first before this patch can be merged:
>
> * The upstream Exynos cpuidle code lacks support for secure firmware and
>    it is used on i.e. Trats2 boards (Exynos4412).  Attempts to use AFTR on
>    such hardware results in oops + lockup.
>    I have patches adding secure firmware support to Exynos cpuidle driver
>    but they depend on Tomasz Figa's PM changes which are not yet upstream.

Ok.

> * Somebody needs to verify that the current Exynos cpuidle driver works
>    in the AFTR mode on Exynos5420 for which support has been added recently
>    (I really doubt it looking at some internal trees).

Rajeshwari (cc'ed) is working on creating a big.Little driver for this 
board, so it will be a separate cpuidle driver.

> * Some of our u-boot bootloader versions are incompatible with AFTR.  We
>    have observed the problem happening on Trats board (Exynos4210) on which
>    it can be fixed by using the upstream u-boot version and Universal C210
>    board (Exynos4210 with broken SMP support) on which there is no upstream
>    u-boot available (IIRC) and because of the broken SMP support enabling
>    cpuidle results in attempt to enter AFTR during boot + immediate lockup.
>
>    I know that this is mainly our problem but the issue is widespread on
>    our targets and I believe that adding some workaround for it in cpuidle
>    core would be beneficial for the whole cpuidle subsystem.  Namely there
>    should be some way of telling cpuidle subsystem to either disable
>    particular state(s) or limit the max available state.  I think that this
>    can be also useful for testing and development of other cpuidle drivers.
>
> For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
> the config option is "default y" it will be auto-enabled if there is no
> entry in the defconfig)..

Ok.

Kukjin, is it possible you merge patches 1->16 ?

Thanks

   -- Daniel

> --
> Bartlomiej Zolnierkiewicz
> Samsung R&D Institute Poland
> Samsung Electronics
>


-- 
  <http://www.linaro.org/> Linaro.org ? Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
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[PATCH V2 16/17] ARM: exynos: cpuidle: Move the driver to drivers/cpuidle directory

[Sachin Kamat]

Hi Daniel,

On 4 April 2014 19:13, Daniel Lezcano <daniel.lezcano@linaro.org> wrote:
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  arch/arm/mach-exynos/Makefile                      |    1 -
>  drivers/cpuidle/Kconfig.arm                        |    7 +++++++
>  drivers/cpuidle/Makefile                           |    1 +
>  .../cpuidle.c => drivers/cpuidle/cpuidle-exynos.c  |    0
>  4 files changed, 8 insertions(+), 1 deletion(-)
>  rename arch/arm/mach-exynos/cpuidle.c => drivers/cpuidle/cpuidle-exynos.c (100%)

This driver now references platform header file (plat/cpu.h) for some
Exynos5440 specific check
which is not good considering multiplatform support. Any plan to get
rid of this?

-- 
With warm regards,
Sachin

[PATCH V2 16/17] ARM: exynos: cpuidle: Move the driver to drivers/cpuidle directory

[Daniel Lezcano]

On 04/07/2014 11:51 AM, Sachin Kamat wrote:
> Hi Daniel,
>
> On 4 April 2014 19:13, Daniel Lezcano <daniel.lezcano@linaro.org> wrote:
>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
>> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
>> ---
>>   arch/arm/mach-exynos/Makefile                      |    1 -
>>   drivers/cpuidle/Kconfig.arm                        |    7 +++++++
>>   drivers/cpuidle/Makefile                           |    1 +
>>   .../cpuidle.c => drivers/cpuidle/cpuidle-exynos.c  |    0
>>   4 files changed, 8 insertions(+), 1 deletion(-)
>>   rename arch/arm/mach-exynos/cpuidle.c => drivers/cpuidle/cpuidle-exynos.c (100%)
>
> This driver now references platform header file (plat/cpu.h) for some
> Exynos5440 specific check
> which is not good considering multiplatform support. Any plan to get
> rid of this?

Yes. Prevent to register the platform device for this board and remove 
these lines in the driver.

What is the benefit of having a single state WFI cpuidle driver ? That 
pulls all the governor computation and decision for nothing.



-- 
  <http://www.linaro.org/> Linaro.org ? Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Bartlomiej Zolnierkiewicz]

On Monday, April 07, 2014 11:43:47 AM Daniel Lezcano wrote:
> On 04/04/2014 06:09 PM, Bartlomiej Zolnierkiewicz wrote:
> >
> > On Friday, April 04, 2014 03:43:09 PM Daniel Lezcano wrote:
> >> The cpuidle driver is broken since v3.11 and now we are at v3.14.
> >>
> >> Default the cpuidle driver to favorize a better detection next time.
> >>
> >> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> >> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
> >> ---
> >>   arch/arm/configs/exynos_defconfig |    1 +
> >>   1 file changed, 1 insertion(+)
> >>
> >> diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
> >> index 4ce7b70..6ed4b34 100644
> >> --- a/arch/arm/configs/exynos_defconfig
> >> +++ b/arch/arm/configs/exynos_defconfig
> >> @@ -132,3 +132,4 @@ CONFIG_DEBUG_INFO=y
> >>   CONFIG_DEBUG_USER=y
> >>   CONFIG_CRYPTO_SHA256=y
> >>   CONFIG_CRC_CCITT=y
> >> +CONFIG_CPU_IDLE=y
> >
> > Sorry but I have to NAK this change.  There are three issues with AFTR
> > mode that should be resolved first before this patch can be merged:
> >
> > * The upstream Exynos cpuidle code lacks support for secure firmware and
> >    it is used on i.e. Trats2 boards (Exynos4412).  Attempts to use AFTR on
> >    such hardware results in oops + lockup.
> >    I have patches adding secure firmware support to Exynos cpuidle driver
> >    but they depend on Tomasz Figa's PM changes which are not yet upstream.
> 
> Ok.
> 
> > * Somebody needs to verify that the current Exynos cpuidle driver works
> >    in the AFTR mode on Exynos5420 for which support has been added recently
> >    (I really doubt it looking at some internal trees).
> 
> Rajeshwari (cc'ed) is working on creating a big.Little driver for this 
> board, so it will be a separate cpuidle driver.
> 
> > * Some of our u-boot bootloader versions are incompatible with AFTR.  We
> >    have observed the problem happening on Trats board (Exynos4210) on which
> >    it can be fixed by using the upstream u-boot version and Universal C210
> >    board (Exynos4210 with broken SMP support) on which there is no upstream
> >    u-boot available (IIRC) and because of the broken SMP support enabling
> >    cpuidle results in attempt to enter AFTR during boot + immediate lockup.
> >
> >    I know that this is mainly our problem but the issue is widespread on
> >    our targets and I believe that adding some workaround for it in cpuidle
> >    core would be beneficial for the whole cpuidle subsystem.  Namely there
> >    should be some way of telling cpuidle subsystem to either disable
> >    particular state(s) or limit the max available state.  I think that this
> >    can be also useful for testing and development of other cpuidle drivers.
> >
> > For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
> > the config option is "default y" it will be auto-enabled if there is no
> > entry in the defconfig)..
> 
> Ok.
> 
> Kukjin, is it possible you merge patches 1->16 ?

It is OK given that patch #17 is fixed and merged at the same time
(preferably it should go before patches #1-16 to preserve bisectability).
Alternatively 'default y' should be removed from patch #16 before
the merge.  We really don't want to have EXYNOS cpuidle driver enabled
by default yet.

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Olof Johansson]

On Mon, Apr 7, 2014 at 9:19 AM, Bartlomiej Zolnierkiewicz
<b.zolnierkie@samsung.com> wrote:
> On Monday, April 07, 2014 11:43:47 AM Daniel Lezcano wrote:
>> On 04/04/2014 06:09 PM, Bartlomiej Zolnierkiewicz wrote:
>> >
>> > On Friday, April 04, 2014 03:43:09 PM Daniel Lezcano wrote:
>> >> The cpuidle driver is broken since v3.11 and now we are at v3.14.
>> >>
>> >> Default the cpuidle driver to favorize a better detection next time.
>> >>
>> >> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
>> >> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
>> >> ---
>> >>   arch/arm/configs/exynos_defconfig |    1 +
>> >>   1 file changed, 1 insertion(+)
>> >>
>> >> diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
>> >> index 4ce7b70..6ed4b34 100644
>> >> --- a/arch/arm/configs/exynos_defconfig
>> >> +++ b/arch/arm/configs/exynos_defconfig
>> >> @@ -132,3 +132,4 @@ CONFIG_DEBUG_INFO=y
>> >>   CONFIG_DEBUG_USER=y
>> >>   CONFIG_CRYPTO_SHA256=y
>> >>   CONFIG_CRC_CCITT=y
>> >> +CONFIG_CPU_IDLE=y
>> >
>> > Sorry but I have to NAK this change.  There are three issues with AFTR
>> > mode that should be resolved first before this patch can be merged:
>> >
>> > * The upstream Exynos cpuidle code lacks support for secure firmware and
>> >    it is used on i.e. Trats2 boards (Exynos4412).  Attempts to use AFTR on
>> >    such hardware results in oops + lockup.
>> >    I have patches adding secure firmware support to Exynos cpuidle driver
>> >    but they depend on Tomasz Figa's PM changes which are not yet upstream.
>>
>> Ok.
>>
>> > * Somebody needs to verify that the current Exynos cpuidle driver works
>> >    in the AFTR mode on Exynos5420 for which support has been added recently
>> >    (I really doubt it looking at some internal trees).
>>
>> Rajeshwari (cc'ed) is working on creating a big.Little driver for this
>> board, so it will be a separate cpuidle driver.
>>
>> > * Some of our u-boot bootloader versions are incompatible with AFTR.  We
>> >    have observed the problem happening on Trats board (Exynos4210) on which
>> >    it can be fixed by using the upstream u-boot version and Universal C210
>> >    board (Exynos4210 with broken SMP support) on which there is no upstream
>> >    u-boot available (IIRC) and because of the broken SMP support enabling
>> >    cpuidle results in attempt to enter AFTR during boot + immediate lockup.
>> >
>> >    I know that this is mainly our problem but the issue is widespread on
>> >    our targets and I believe that adding some workaround for it in cpuidle
>> >    core would be beneficial for the whole cpuidle subsystem.  Namely there
>> >    should be some way of telling cpuidle subsystem to either disable
>> >    particular state(s) or limit the max available state.  I think that this
>> >    can be also useful for testing and development of other cpuidle drivers.
>> >
>> > For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
>> > the config option is "default y" it will be auto-enabled if there is no
>> > entry in the defconfig)..
>>
>> Ok.
>>
>> Kukjin, is it possible you merge patches 1->16 ?
>
> It is OK given that patch #17 is fixed and merged at the same time
> (preferably it should go before patches #1-16 to preserve bisectability).
> Alternatively 'default y' should be removed from patch #16 before
> the merge.  We really don't want to have EXYNOS cpuidle driver enabled
> by default yet.

Default y is almost always the wrong thing to use, so that should be
taken out no matter what.


-Olof

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Olof Johansson]

On Fri, Apr 4, 2014 at 9:09 AM, Bartlomiej Zolnierkiewicz
<b.zolnierkie@samsung.com> wrote:

[...]
>   I know that this is mainly our problem but the issue is widespread on
>   our targets and I believe that adding some workaround for it in cpuidle
>   core would be beneficial for the whole cpuidle subsystem.

Yes, we need to find a way forward without you guys holding the whole
platform hostage with out-of-tree code (here and in general, since I
think there are more areas in which this applies).

>  Namely there
>   should be some way of telling cpuidle subsystem to either disable
>   particular state(s) or limit the max available state.  I think that this
>   can be also useful for testing and development of other cpuidle drivers.
>
> For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
> the config option is "default y" it will be auto-enabled if there is no
> entry in the defconfig)..

Can the code be refactored such that even if CPU_IDLE is on, it won't
actually do anything useful on the platforms that have problems above?
I.e. determined at runtime, not build time?


(I have not yet looked at the rest of the series).


-Olof

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Bartlomiej Zolnierkiewicz]

Hi,

On Monday, April 07, 2014 09:28:39 AM Olof Johansson wrote:
> On Fri, Apr 4, 2014 at 9:09 AM, Bartlomiej Zolnierkiewicz
> <b.zolnierkie@samsung.com> wrote:
> 
> [...]
> >   I know that this is mainly our problem but the issue is widespread on
> >   our targets and I believe that adding some workaround for it in cpuidle
> >   core would be beneficial for the whole cpuidle subsystem.

On the second look at the cpuidle code there is a "cpuidle.off" kernel
parameter which should be sufficient to workaround this particular issue
for now.

> Yes, we need to find a way forward without you guys holding the whole
> platform hostage with out-of-tree code (here and in general, since I
> think there are more areas in which this applies).

Please explain this more because I really don't know what you're meaning
here (at least in case of SRPOL I feel that there are no such issues).

In this particular case we have a problem with a modified uboot bootloader
versions being broken and incompatible with the advanced AFTR cpuidle mode.
This is not the only / main issue preventing AFTR mode and thus EXYNOS
cpuidle driver from being used by default so I really think that the your
comment was unfair.

> >  Namely there
> >   should be some way of telling cpuidle subsystem to either disable
> >   particular state(s) or limit the max available state.  I think that this
> >   can be also useful for testing and development of other cpuidle drivers.
> >
> > For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
> > the config option is "default y" it will be auto-enabled if there is no
> > entry in the defconfig)..
> 
> Can the code be refactored such that even if CPU_IDLE is on, it won't
> actually do anything useful on the platforms that have problems above?
> I.e. determined at runtime, not build time?

We can disable AFTR mode by default on EXYNOS4x12 SoCs with secure mode
enabled and EXYNOS5420 SoCs (I would like somebody with the hardware to
verify that AFTR mode is not working first so we have 100% certainty
that we don't regress here).

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Olof Johansson]

On Mon, Apr 7, 2014 at 10:44 AM, Bartlomiej Zolnierkiewicz
<b.zolnierkie@samsung.com> wrote:
>
> Hi,
>
> On Monday, April 07, 2014 09:28:39 AM Olof Johansson wrote:
>> On Fri, Apr 4, 2014 at 9:09 AM, Bartlomiej Zolnierkiewicz
>> <b.zolnierkie@samsung.com> wrote:
>>
>> [...]
>> >   I know that this is mainly our problem but the issue is widespread on
>> >   our targets and I believe that adding some workaround for it in cpuidle
>> >   core would be beneficial for the whole cpuidle subsystem.
>
> On the second look at the cpuidle code there is a "cpuidle.off" kernel
> parameter which should be sufficient to workaround this particular issue
> for now.
>
>> Yes, we need to find a way forward without you guys holding the whole
>> platform hostage with out-of-tree code (here and in general, since I
>> think there are more areas in which this applies).
>
> Please explain this more because I really don't know what you're meaning
> here (at least in case of SRPOL I feel that there are no such issues).
>
> In this particular case we have a problem with a modified uboot bootloader
> versions being broken and incompatible with the advanced AFTR cpuidle mode.
> This is not the only / main issue preventing AFTR mode and thus EXYNOS
> cpuidle driver from being used by default so I really think that the your
> comment was unfair.

Holding off features for users of the platform because your firmware
is too old (and you can't control the feature per platform) is going
to get harder and harder, so being able to enable these kind of things
at runtime will be important. I.e. as features go in, it's something
that needs to be considered (runtime checking vs ifdef).

Calling that hostage taking? Yeah, maybe a little on the harsh side.
But the problem definitely exists.

>> >  Namely there
>> >   should be some way of telling cpuidle subsystem to either disable
>> >   particular state(s) or limit the max available state.  I think that this
>> >   can be also useful for testing and development of other cpuidle drivers.
>> >
>> > For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
>> > the config option is "default y" it will be auto-enabled if there is no
>> > entry in the defconfig)..
>>
>> Can the code be refactored such that even if CPU_IDLE is on, it won't
>> actually do anything useful on the platforms that have problems above?
>> I.e. determined at runtime, not build time?
>
> We can disable AFTR mode by default on EXYNOS4x12 SoCs with secure mode
> enabled and EXYNOS5420 SoCs (I would like somebody with the hardware to
> verify that AFTR mode is not working first so we have 100% certainty
> that we don't regress here).

Does 5420 even work upstream? I have hardware access but nothing that
will run an upstream kernel as far as I know. Maybe SLSI has an SMDK
they can help out with?


-Olof

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Sachin Kamat]

On 8 April 2014 00:03, Olof Johansson <olof@lixom.net> wrote:
> On Mon, Apr 7, 2014 at 10:44 AM, Bartlomiej Zolnierkiewicz
> <b.zolnierkie@samsung.com> wrote:
>>
>> Hi,
>>
>> On Monday, April 07, 2014 09:28:39 AM Olof Johansson wrote:
>>> On Fri, Apr 4, 2014 at 9:09 AM, Bartlomiej Zolnierkiewicz
>>> <b.zolnierkie@samsung.com> wrote:
>>>
>>> [...]
>
> Does 5420 even work upstream? I have hardware access but nothing that
> will run an upstream kernel as far as I know. Maybe SLSI has an SMDK
> they can help out with?

By working upstream if you mean being bootable, then yes I am able to boot both
SMDK and Arndale Octa boards based on 5420 with the current upstream kernel.
CPU idle however doesn't work though. I get a crash when I hot plug out all
secondary CPUs on SMDK.

-- 
With warm regards,
Sachin

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Bartlomiej Zolnierkiewicz]

On Monday, April 07, 2014 11:33:57 AM Olof Johansson wrote:
> On Mon, Apr 7, 2014 at 10:44 AM, Bartlomiej Zolnierkiewicz
> <b.zolnierkie@samsung.com> wrote:
> >
> > Hi,
> >
> > On Monday, April 07, 2014 09:28:39 AM Olof Johansson wrote:
> >> On Fri, Apr 4, 2014 at 9:09 AM, Bartlomiej Zolnierkiewicz
> >> <b.zolnierkie@samsung.com> wrote:
> >>
> >> [...]
> >> >   I know that this is mainly our problem but the issue is widespread on
> >> >   our targets and I believe that adding some workaround for it in cpuidle
> >> >   core would be beneficial for the whole cpuidle subsystem.
> >
> > On the second look at the cpuidle code there is a "cpuidle.off" kernel
> > parameter which should be sufficient to workaround this particular issue
> > for now.
> >
> >> Yes, we need to find a way forward without you guys holding the whole
> >> platform hostage with out-of-tree code (here and in general, since I
> >> think there are more areas in which this applies).
> >
> > Please explain this more because I really don't know what you're meaning
> > here (at least in case of SRPOL I feel that there are no such issues).
> >
> > In this particular case we have a problem with a modified uboot bootloader
> > versions being broken and incompatible with the advanced AFTR cpuidle mode.
> > This is not the only / main issue preventing AFTR mode and thus EXYNOS
> > cpuidle driver from being used by default so I really think that the your
> > comment was unfair.
> 
> Holding off features for users of the platform because your firmware
> is too old (and you can't control the feature per platform) is going
> to get harder and harder, so being able to enable these kind of things
> at runtime will be important. I.e. as features go in, it's something
> that needs to be considered (runtime checking vs ifdef).

In this particular case runtime detection of broken uboot versions is not
possible, otherwise the issue would have been addressed a long time ago.

Anyway this is not the main problem here and we can deal with it on our
side (we will just use "cpuidle.off" on our affected targets).

> Calling that hostage taking? Yeah, maybe a little on the harsh side.
> But the problem definitely exists.

I don't agree that there is some kind of general problem on our side
and you've not provided any specific issues that would fall under this
category.

> >> >  Namely there
> >> >   should be some way of telling cpuidle subsystem to either disable
> >> >   particular state(s) or limit the max available state.  I think that this
> >> >   can be also useful for testing and development of other cpuidle drivers.
> >> >
> >> > For now please change this patch to add CONFIG_CPU_IDLE=n instead (since
> >> > the config option is "default y" it will be auto-enabled if there is no
> >> > entry in the defconfig)..
> >>
> >> Can the code be refactored such that even if CPU_IDLE is on, it won't
> >> actually do anything useful on the platforms that have problems above?
> >> I.e. determined at runtime, not build time?
> >
> > We can disable AFTR mode by default on EXYNOS4x12 SoCs with secure mode
> > enabled and EXYNOS5420 SoCs (I would like somebody with the hardware to
> > verify that AFTR mode is not working first so we have 100% certainty
> > that we don't regress here).
> 
> Does 5420 even work upstream? I have hardware access but nothing that
> will run an upstream kernel as far as I know. Maybe SLSI has an SMDK
> they can help out with?

I don't know the current status of 5420.  The initial support was added by
Linaro (I added Chander and Sachin to cc:).

If the upstream support is working to check the AFTR mode one needs to
enable cpuidle driver (CONFIG_CPU_IDLE=y) and offline all CPUs except CPU0
(through sysfs using "echo 0 > /sys/devices/system/cpu/cpuX/online").

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH V2 17/17] ARM: exynos: config: Enable cpuidle

[Bartlomiej Zolnierkiewicz]

On Tuesday, April 08, 2014 09:27:04 AM Sachin Kamat wrote:
> On 8 April 2014 00:03, Olof Johansson <olof@lixom.net> wrote:
> > On Mon, Apr 7, 2014 at 10:44 AM, Bartlomiej Zolnierkiewicz
> > <b.zolnierkie@samsung.com> wrote:
> >>
> >> Hi,
> >>
> >> On Monday, April 07, 2014 09:28:39 AM Olof Johansson wrote:
> >>> On Fri, Apr 4, 2014 at 9:09 AM, Bartlomiej Zolnierkiewicz
> >>> <b.zolnierkie@samsung.com> wrote:
> >>>
> >>> [...]
> >
> > Does 5420 even work upstream? I have hardware access but nothing that
> > will run an upstream kernel as far as I know. Maybe SLSI has an SMDK
> > they can help out with?
> 
> By working upstream if you mean being bootable, then yes I am able to boot both
> SMDK and Arndale Octa boards based on 5420 with the current upstream kernel.
> CPU idle however doesn't work though. I get a crash when I hot plug out all
> secondary CPUs on SMDK.

Thanks for testing.  This behavior is an expected one given the current code
(=> we need to disable AFTR on 5420 for now).

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics