[RFC PATCH 0/2] ARM: at91: cpuidle: encapsulate and move the driver to drivers/cpuidle

[RFC PATCH 0/2] ARM: at91: cpuidle: encapsulate and move the driver to drivers/cpuidle

[Daniel Lezcano]

Several patches were send to encapsulate the standby code.

Creating a platform driver model allows to finish to encapsulate this code more
and make possible to move the driver to the drivers/cpuidle directory.

I was not able to test the patchset, I don't have the hardware.

Daniel Lezcano (2):
  ARM: at91: cpuidle: convert to platform driver
  ARM: at91: cpuidle: Move driver to drivers/cpuidle

 arch/arm/mach-at91/Makefile    |    1 -
 arch/arm/mach-at91/cpuidle.c   |   68 ---------------------------------------
 arch/arm/mach-at91/pm.c        |   16 +++++++++-
 drivers/cpuidle/Kconfig.arm    |    6 ++++
 drivers/cpuidle/Makefile       |    1 +
 drivers/cpuidle/cpuidle-at91.c |   69 ++++++++++++++++++++++++++++++++++++++++
 6 files changed, 91 insertions(+), 70 deletions(-)
 delete mode 100644 arch/arm/mach-at91/cpuidle.c
 create mode 100644 drivers/cpuidle/cpuidle-at91.c

-- 
1.7.9.5

[RFC PATCH 1/2] ARM: at91: cpuidle: convert to platform driver

[Daniel Lezcano]

Using the platform driver model is a good way to separate the cpuidle specific
code from the low level pm code. It allows to remove the dependency between
these two components.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 arch/arm/mach-at91/cpuidle.c |   29 +++++++++++++++--------------
 arch/arm/mach-at91/pm.c      |   16 +++++++++++++++-
 2 files changed, 30 insertions(+), 15 deletions(-)

diff --git a/arch/arm/mach-at91/cpuidle.c b/arch/arm/mach-at91/cpuidle.c
index 4ec6a6d..6cdc76d 100644
--- a/arch/arm/mach-at91/cpuidle.c
+++ b/arch/arm/mach-at91/cpuidle.c
@@ -21,26 +21,17 @@
 #include <linux/export.h>
 #include <asm/proc-fns.h>
 #include <asm/cpuidle.h>
-#include <mach/cpu.h>
-
-#include "pm.h"
 
 #define AT91_MAX_STATES	2
 
+static void (*at91_standby)(void);
+
 /* Actual code that puts the SoC in different idle states */
 static int at91_enter_idle(struct cpuidle_device *dev,
 			struct cpuidle_driver *drv,
 			       int index)
 {
-	if (cpu_is_at91rm9200())
-		at91rm9200_standby();
-	else if (cpu_is_at91sam9g45())
-		at91sam9g45_standby();
-	else if (cpu_is_at91sam9263())
-		at91sam9263_standby();
-	else
-		at91sam9_standby();
-
+	at91_standby();
 	return index;
 }
 
@@ -60,9 +51,19 @@ static struct cpuidle_driver at91_idle_driver = {
 };
 
 /* Initialize CPU idle by registering the idle states */
-static int __init at91_init_cpuidle(void)
+static int __init at91_cpuidle_probe(struct platform_device *dev)
 {
+	at91_standby = (void *)(dev->dev.platform_data);
+	
 	return cpuidle_register(&at91_idle_driver, NULL);
 }
 
-device_initcall(at91_init_cpuidle);
+static struct platform_driver at91_cpuidle_driver = {
+	.driver = {
+		.name = "cpuidle-at91",
+		.owner = THIS_MODULE,
+	},
+	.probe = at91_cpuidle_probe,
+};
+
+module_platform_driver(at91_cpuidle_driver);
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 15afb5d..debdbf8 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -314,6 +314,10 @@ static const struct platform_suspend_ops at91_pm_ops = {
 	.end	= at91_pm_end,
 };
 
+static struct platform_device at91_cpuidle_device = {
+	.name = "cpuidle-at91",
+};
+
 static int __init at91_pm_init(void)
 {
 #ifdef CONFIG_AT91_SLOW_CLOCK
@@ -323,8 +327,18 @@ static int __init at91_pm_init(void)
 	pr_info("AT91: Power Management%s\n", (slow_clock ? " (with slow clock mode)" : ""));
 
 	/* AT91RM9200 SDRAM low-power mode cannot be used with self-refresh. */
-	if (cpu_is_at91rm9200())
+	if (cpu_is_at91rm9200()) {
+		at91_cpuidle_device.dev.platform_data = at91rm9200_standby;
 		at91_ramc_write(0, AT91RM9200_SDRAMC_LPR, 0);
+	} else if (cpu_is_at91sam9g45()) {
+		at91_cpuidle_device.dev.platform_data = at91sam9g45_standby;
+	} else if (cpu_is_at91sam9263()) {
+		at91_cpuidle_device.dev.platform_data = at91sam9263_standby;
+	} else {
+		at91_cpuidle_device.dev.platform_data = at91sam9_standby;
+	}
+	
+	platform_device_register(&at91_cpuidle_device);
 
 	suspend_set_ops(&at91_pm_ops);
 
-- 
1.7.9.5

[RFC PATCH 2/2] ARM: at91: cpuidle: Move driver to drivers/cpuidle

[Daniel Lezcano]

As the cpuidle driver code has no more the dependency with the pm code, the
'standby' callback being passed as a parameter to the device's platform data,
we can move the cpuidle driver in the drivers/cpuidle directory.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 arch/arm/mach-at91/Makefile    |    1 -
 arch/arm/mach-at91/cpuidle.c   |   69 ----------------------------------------
 drivers/cpuidle/Kconfig.arm    |    6 ++++
 drivers/cpuidle/Makefile       |    1 +
 drivers/cpuidle/cpuidle-at91.c |   69 ++++++++++++++++++++++++++++++++++++++++
 5 files changed, 76 insertions(+), 70 deletions(-)
 delete mode 100644 arch/arm/mach-at91/cpuidle.c
 create mode 100644 drivers/cpuidle/cpuidle-at91.c

diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
index 3b0a953..c1b7370 100644
--- a/arch/arm/mach-at91/Makefile
+++ b/arch/arm/mach-at91/Makefile
@@ -98,7 +98,6 @@ obj-y				+= leds.o
 # Power Management
 obj-$(CONFIG_PM)		+= pm.o
 obj-$(CONFIG_AT91_SLOW_CLOCK)	+= pm_slowclock.o
-obj-$(CONFIG_CPU_IDLE)	+= cpuidle.o
 
 ifeq ($(CONFIG_PM_DEBUG),y)
 CFLAGS_pm.o += -DDEBUG
diff --git a/arch/arm/mach-at91/cpuidle.c b/arch/arm/mach-at91/cpuidle.c
deleted file mode 100644
index 6cdc76d..0000000
--- a/arch/arm/mach-at91/cpuidle.c
+++ /dev/null
@@ -1,69 +0,0 @@
-/*
- * based on arch/arm/mach-kirkwood/cpuidle.c
- *
- * CPU idle support for AT91 SoC
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2.  This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- *
- * The cpu idle uses wait-for-interrupt and RAM self refresh in order
- * to implement two idle states -
- * #1 wait-for-interrupt
- * #2 wait-for-interrupt and RAM self refresh
- */
-
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/platform_device.h>
-#include <linux/cpuidle.h>
-#include <linux/io.h>
-#include <linux/export.h>
-#include <asm/proc-fns.h>
-#include <asm/cpuidle.h>
-
-#define AT91_MAX_STATES	2
-
-static void (*at91_standby)(void);
-
-/* Actual code that puts the SoC in different idle states */
-static int at91_enter_idle(struct cpuidle_device *dev,
-			struct cpuidle_driver *drv,
-			       int index)
-{
-	at91_standby();
-	return index;
-}
-
-static struct cpuidle_driver at91_idle_driver = {
-	.name			= "at91_idle",
-	.owner			= THIS_MODULE,
-	.states[0]		= ARM_CPUIDLE_WFI_STATE,
-	.states[1]		= {
-		.enter			= at91_enter_idle,
-		.exit_latency		= 10,
-		.target_residency	= 10000,
-		.flags			= CPUIDLE_FLAG_TIME_VALID,
-		.name			= "RAM_SR",
-		.desc			= "WFI and DDR Self Refresh",
-	},
-	.state_count = AT91_MAX_STATES,
-};
-
-/* Initialize CPU idle by registering the idle states */
-static int __init at91_cpuidle_probe(struct platform_device *dev)
-{
-	at91_standby = (void *)(dev->dev.platform_data);
-	
-	return cpuidle_register(&at91_idle_driver, NULL);
-}
-
-static struct platform_driver at91_cpuidle_driver = {
-	.driver = {
-		.name = "cpuidle-at91",
-		.owner = THIS_MODULE,
-	},
-	.probe = at91_cpuidle_probe,
-};
-
-module_platform_driver(at91_cpuidle_driver);
diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index 8e36603..edecfc8 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm
@@ -27,6 +27,12 @@ config ARM_U8500_CPUIDLE
 	help
 	  Select this to enable cpuidle for ST-E u8500 processors
 
+config ARM_AT91_CPUIDLE
+        bool "Cpu Idle Driver for the AT91 processors"
+	depends on ARCH_AT91
+	help
+	  Select this to enable cpuidle for AT91 processors
+
 config CPU_IDLE_BIG_LITTLE
 	bool "Support for ARM big.LITTLE processors"
 	depends on ARCH_VEXPRESS_TC2_PM
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index cea5ef5..60c4ae5 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -11,4 +11,5 @@ obj-$(CONFIG_ARM_HIGHBANK_CPUIDLE)	+= cpuidle-calxeda.o
 obj-$(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_CPU_IDLE_BIG_LITTLE)	+= cpuidle-big_little.o
diff --git a/drivers/cpuidle/cpuidle-at91.c b/drivers/cpuidle/cpuidle-at91.c
new file mode 100644
index 0000000..6cdc76d
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-at91.c
@@ -0,0 +1,69 @@
+/*
+ * based on arch/arm/mach-kirkwood/cpuidle.c
+ *
+ * CPU idle support for AT91 SoC
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * The cpu idle uses wait-for-interrupt and RAM self refresh in order
+ * to implement two idle states -
+ * #1 wait-for-interrupt
+ * #2 wait-for-interrupt and RAM self refresh
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/cpuidle.h>
+#include <linux/io.h>
+#include <linux/export.h>
+#include <asm/proc-fns.h>
+#include <asm/cpuidle.h>
+
+#define AT91_MAX_STATES	2
+
+static void (*at91_standby)(void);
+
+/* Actual code that puts the SoC in different idle states */
+static int at91_enter_idle(struct cpuidle_device *dev,
+			struct cpuidle_driver *drv,
+			       int index)
+{
+	at91_standby();
+	return index;
+}
+
+static struct cpuidle_driver at91_idle_driver = {
+	.name			= "at91_idle",
+	.owner			= THIS_MODULE,
+	.states[0]		= ARM_CPUIDLE_WFI_STATE,
+	.states[1]		= {
+		.enter			= at91_enter_idle,
+		.exit_latency		= 10,
+		.target_residency	= 10000,
+		.flags			= CPUIDLE_FLAG_TIME_VALID,
+		.name			= "RAM_SR",
+		.desc			= "WFI and DDR Self Refresh",
+	},
+	.state_count = AT91_MAX_STATES,
+};
+
+/* Initialize CPU idle by registering the idle states */
+static int __init at91_cpuidle_probe(struct platform_device *dev)
+{
+	at91_standby = (void *)(dev->dev.platform_data);
+	
+	return cpuidle_register(&at91_idle_driver, NULL);
+}
+
+static struct platform_driver at91_cpuidle_driver = {
+	.driver = {
+		.name = "cpuidle-at91",
+		.owner = THIS_MODULE,
+	},
+	.probe = at91_cpuidle_probe,
+};
+
+module_platform_driver(at91_cpuidle_driver);
-- 
1.7.9.5

Re: [RFC PATCH 2/2] ARM: at91: cpuidle: Move driver to drivers/cpuidle

[Bartlomiej Zolnierkiewicz]

Hi,

On Thursday, September 26, 2013 06:06:07 PM Daniel Lezcano wrote:
> As the cpuidle driver code has no more the dependency with the pm code, the
> 'standby' callback being passed as a parameter to the device's platform data,
> we can move the cpuidle driver in the drivers/cpuidle directory.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> ---
>  arch/arm/mach-at91/Makefile    |    1 -
>  arch/arm/mach-at91/cpuidle.c   |   69 ----------------------------------------
>  drivers/cpuidle/Kconfig.arm    |    6 ++++
>  drivers/cpuidle/Makefile       |    1 +
>  drivers/cpuidle/cpuidle-at91.c |   69 ++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 76 insertions(+), 70 deletions(-)
>  delete mode 100644 arch/arm/mach-at91/cpuidle.c
>  create mode 100644 drivers/cpuidle/cpuidle-at91.c
> 
> diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
> index 3b0a953..c1b7370 100644
> --- a/arch/arm/mach-at91/Makefile
> +++ b/arch/arm/mach-at91/Makefile
> @@ -98,7 +98,6 @@ obj-y				+= leds.o
>  # Power Management
>  obj-$(CONFIG_PM)		+= pm.o
>  obj-$(CONFIG_AT91_SLOW_CLOCK)	+= pm_slowclock.o
> -obj-$(CONFIG_CPU_IDLE)	+= cpuidle.o
>  
>  ifeq ($(CONFIG_PM_DEBUG),y)
>  CFLAGS_pm.o += -DDEBUG
> diff --git a/arch/arm/mach-at91/cpuidle.c b/arch/arm/mach-at91/cpuidle.c
> deleted file mode 100644
> index 6cdc76d..0000000
> --- a/arch/arm/mach-at91/cpuidle.c
> +++ /dev/null
> @@ -1,69 +0,0 @@
> -/*
> - * based on arch/arm/mach-kirkwood/cpuidle.c
> - *
> - * CPU idle support for AT91 SoC
> - *
> - * This file is licensed under the terms of the GNU General Public
> - * License version 2.  This program is licensed "as is" without any
> - * warranty of any kind, whether express or implied.
> - *
> - * The cpu idle uses wait-for-interrupt and RAM self refresh in order
> - * to implement two idle states -
> - * #1 wait-for-interrupt
> - * #2 wait-for-interrupt and RAM self refresh
> - */
> -
> -#include <linux/kernel.h>
> -#include <linux/init.h>
> -#include <linux/platform_device.h>
> -#include <linux/cpuidle.h>
> -#include <linux/io.h>
> -#include <linux/export.h>
> -#include <asm/proc-fns.h>
> -#include <asm/cpuidle.h>
> -
> -#define AT91_MAX_STATES	2
> -
> -static void (*at91_standby)(void);
> -
> -/* Actual code that puts the SoC in different idle states */
> -static int at91_enter_idle(struct cpuidle_device *dev,
> -			struct cpuidle_driver *drv,
> -			       int index)
> -{
> -	at91_standby();
> -	return index;
> -}
> -
> -static struct cpuidle_driver at91_idle_driver = {
> -	.name			= "at91_idle",
> -	.owner			= THIS_MODULE,
> -	.states[0]		= ARM_CPUIDLE_WFI_STATE,
> -	.states[1]		= {
> -		.enter			= at91_enter_idle,
> -		.exit_latency		= 10,
> -		.target_residency	= 10000,
> -		.flags			= CPUIDLE_FLAG_TIME_VALID,
> -		.name			= "RAM_SR",
> -		.desc			= "WFI and DDR Self Refresh",
> -	},
> -	.state_count = AT91_MAX_STATES,
> -};
> -
> -/* Initialize CPU idle by registering the idle states */
> -static int __init at91_cpuidle_probe(struct platform_device *dev)
> -{
> -	at91_standby = (void *)(dev->dev.platform_data);
> -	
> -	return cpuidle_register(&at91_idle_driver, NULL);
> -}
> -
> -static struct platform_driver at91_cpuidle_driver = {
> -	.driver = {
> -		.name = "cpuidle-at91",
> -		.owner = THIS_MODULE,
> -	},
> -	.probe = at91_cpuidle_probe,
> -};
> -
> -module_platform_driver(at91_cpuidle_driver);
> diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
> index 8e36603..edecfc8 100644
> --- a/drivers/cpuidle/Kconfig.arm
> +++ b/drivers/cpuidle/Kconfig.arm
> @@ -27,6 +27,12 @@ config ARM_U8500_CPUIDLE
>  	help
>  	  Select this to enable cpuidle for ST-E u8500 processors
>  
> +config ARM_AT91_CPUIDLE
> +        bool "Cpu Idle Driver for the AT91 processors"

whitespace damage, please replace spaces by tab

> +	depends on ARCH_AT91

I believe that it should be also "default y" here to preserve the old
behavior (the driver was always built-in for CONFIG_CPU_IDLE=y).

> +	help
> +	  Select this to enable cpuidle for AT91 processors
> +
>  config CPU_IDLE_BIG_LITTLE
>  	bool "Support for ARM big.LITTLE processors"
>  	depends on ARCH_VEXPRESS_TC2_PM
> diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
> index cea5ef5..60c4ae5 100644
> --- a/drivers/cpuidle/Makefile
> +++ b/drivers/cpuidle/Makefile
> @@ -11,4 +11,5 @@ obj-$(CONFIG_ARM_HIGHBANK_CPUIDLE)	+= cpuidle-calxeda.o
>  obj-$(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_CPU_IDLE_BIG_LITTLE)	+= cpuidle-big_little.o
> diff --git a/drivers/cpuidle/cpuidle-at91.c b/drivers/cpuidle/cpuidle-at91.c
> new file mode 100644
> index 0000000..6cdc76d
> --- /dev/null
> +++ b/drivers/cpuidle/cpuidle-at91.c
> @@ -0,0 +1,69 @@
> +/*
> + * based on arch/arm/mach-kirkwood/cpuidle.c
> + *
> + * CPU idle support for AT91 SoC
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2.  This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + *
> + * The cpu idle uses wait-for-interrupt and RAM self refresh in order
> + * to implement two idle states -
> + * #1 wait-for-interrupt
> + * #2 wait-for-interrupt and RAM self refresh
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/platform_device.h>
> +#include <linux/cpuidle.h>
> +#include <linux/io.h>
> +#include <linux/export.h>
> +#include <asm/proc-fns.h>
> +#include <asm/cpuidle.h>
> +
> +#define AT91_MAX_STATES	2
> +
> +static void (*at91_standby)(void);
> +
> +/* Actual code that puts the SoC in different idle states */
> +static int at91_enter_idle(struct cpuidle_device *dev,
> +			struct cpuidle_driver *drv,
> +			       int index)
> +{
> +	at91_standby();
> +	return index;
> +}
> +
> +static struct cpuidle_driver at91_idle_driver = {
> +	.name			= "at91_idle",
> +	.owner			= THIS_MODULE,
> +	.states[0]		= ARM_CPUIDLE_WFI_STATE,
> +	.states[1]		= {
> +		.enter			= at91_enter_idle,
> +		.exit_latency		= 10,
> +		.target_residency	= 10000,
> +		.flags			= CPUIDLE_FLAG_TIME_VALID,
> +		.name			= "RAM_SR",
> +		.desc			= "WFI and DDR Self Refresh",
> +	},
> +	.state_count = AT91_MAX_STATES,
> +};
> +
> +/* Initialize CPU idle by registering the idle states */
> +static int __init at91_cpuidle_probe(struct platform_device *dev)
> +{
> +	at91_standby = (void *)(dev->dev.platform_data);
> +	
> +	return cpuidle_register(&at91_idle_driver, NULL);
> +}
> +
> +static struct platform_driver at91_cpuidle_driver = {
> +	.driver = {
> +		.name = "cpuidle-at91",
> +		.owner = THIS_MODULE,
> +	},
> +	.probe = at91_cpuidle_probe,
> +};
> +
> +module_platform_driver(at91_cpuidle_driver);

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

Re: [RFC PATCH 0/2] ARM: at91: cpuidle: encapsulate and move the driver to drivers/cpuidle

[Daniel Lezcano]

On 09/26/2013 06:06 PM, Daniel Lezcano wrote:
> Several patches were send to encapsulate the standby code.
>
> Creating a platform driver model allows to finish to encapsulate this code more
> and make possible to move the driver to the drivers/cpuidle directory.
>
> I was not able to test the patchset, I don't have the hardware.
>
> Daniel Lezcano (2):
>    ARM: at91: cpuidle: convert to platform driver
>    ARM: at91: cpuidle: Move driver to drivers/cpuidle
>
>   arch/arm/mach-at91/Makefile    |    1 -
>   arch/arm/mach-at91/cpuidle.c   |   68 ---------------------------------------
>   arch/arm/mach-at91/pm.c        |   16 +++++++++-
>   drivers/cpuidle/Kconfig.arm    |    6 ++++
>   drivers/cpuidle/Makefile       |    1 +
>   drivers/cpuidle/cpuidle-at91.c |   69 ++++++++++++++++++++++++++++++++++++++++
>   6 files changed, 91 insertions(+), 70 deletions(-)
>   delete mode 100644 arch/arm/mach-at91/cpuidle.c
>   create mode 100644 drivers/cpuidle/cpuidle-at91.c

ping ?


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