Re: [PATCH v1 2/4] ARM: keystone: pm: switch to use generic pm domains

[Santosh Shilimkar <santosh.shilimkar@ti.com>]

On Monday 29 September 2014 10:38 AM, Grygorii Strashko wrote:
> This patch switches Keystone 2 PM code to use Generic PM domains
> instead of PM clock domains because of the lack of DT support
> for the last.
> 
> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
> ---
>  .../devicetree/bindings/power/ti,keystone-gpc.txt  |  31 ++++++
>  arch/arm/mach-keystone/Kconfig                     |   1 +
>  arch/arm/mach-keystone/pm_domain.c                 | 115 ++++++++++++++-------
>  3 files changed, 110 insertions(+), 37 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/power/ti,keystone-gpc.txt
> 
> diff --git a/Documentation/devicetree/bindings/power/ti,keystone-gpc.txt b/Documentation/devicetree/bindings/power/ti,keystone-gpc.txt
> new file mode 100644
> index 0000000..43af1fc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/ti,keystone-gpc.txt
> @@ -0,0 +1,31 @@
> +* TI Keystone 2 Generic PM Controller
> +
> +The TI Keystone 2 Generic PM Controller is responsible for Clock gating
> +for each controlled IP module.
> +
> +Required properties:
> +- compatible: Should be "ti,keystone-gpc"
> +- #power-domain-cells: Should be 0, see below:
> +
> +The gpc node is a power-controller as documented by the generic power domain
> +bindings in Documentation/devicetree/bindings/power/power_domain.txt.
> +
> +Example:
> +
> +	pm_controller: pm-controller {
> +		compatible = "ti,keystone-gpc";
'gpc' doesn't make it clear. May be 'keystone-powerdomain' ?
> +		#power-domain-cells = <0>;
> +	};
> +
> +	netcp: netcp@2090000 {
> +		reg = <0x2620110 0x8>;
> +		reg-names = "efuse";
> +		...
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		ranges;
> +		power-domains = <&pm_controller>;
> +
> +		clocks = <&clkpa>, <&clkcpgmac>, <&chipclk12>;
> +		dma-coherent;
> +	}
> diff --git a/arch/arm/mach-keystone/Kconfig b/arch/arm/mach-keystone/Kconfig
> index e571084..0132bde 100644
> --- a/arch/arm/mach-keystone/Kconfig
> +++ b/arch/arm/mach-keystone/Kconfig
> @@ -9,6 +9,7 @@ config ARCH_KEYSTONE
>  	select COMMON_CLK_KEYSTONE
>  	select ARCH_SUPPORTS_BIG_ENDIAN
>  	select ZONE_DMA if ARM_LPAE
> +	select PM_GENERIC_DOMAINS if PM
>  	help
>  	  Support for boards based on the Texas Instruments Keystone family of
>  	  SoCs.
> diff --git a/arch/arm/mach-keystone/pm_domain.c b/arch/arm/mach-keystone/pm_domain.c
> index ca79dda..3eb5257 100644
> --- a/arch/arm/mach-keystone/pm_domain.c
> +++ b/arch/arm/mach-keystone/pm_domain.c
> @@ -12,69 +12,110 @@
>   * version 2, as published by the Free Software Foundation.
>   */
>  
> +#include <linux/clk.h>
>  #include <linux/init.h>
> -#include <linux/pm_runtime.h>
>  #include <linux/pm_clock.h>
> +#include <linux/pm_domain.h>
>  #include <linux/platform_device.h>
> -#include <linux/clk-provider.h>
>  #include <linux/of.h>
>  
> -#ifdef CONFIG_PM_RUNTIME
> -static int keystone_pm_runtime_suspend(struct device *dev)
> +#ifdef CONFIG_PM_GENERIC_DOMAINS
> +
> +struct keystone_domain {
> +	struct generic_pm_domain base;
> +	struct device	*dev;
> +};
> +
> +void keystone_pm_domain_attach_dev(struct device *dev)
>  {
> +	struct clk *clk;
>  	int ret;
> +	int i = 0;
>  
>  	dev_dbg(dev, "%s\n", __func__);
>  
> -	ret = pm_generic_runtime_suspend(dev);
> -	if (ret)
> -		return ret;
> -
> -	ret = pm_clk_suspend(dev);
> +	ret = pm_clk_create(dev);
>  	if (ret) {
> -		pm_generic_runtime_resume(dev);
> -		return ret;
> +		dev_err(dev, "pm_clk_create failed %d\n", ret);
> +		return;
> +	};
> +
> +	while ((clk = of_clk_get(dev->of_node, i++)) && !IS_ERR(clk)) {
> +		ret = pm_clk_add_clk(dev, clk);
> +		if (ret) {
> +			dev_err(dev, "pm_clk_add_clk failed %d\n", ret);
> +			goto clk_err;
> +		};
>  	}
>  
> -	return 0;
> +	if (!IS_ENABLED(CONFIG_PM_RUNTIME)) {
> +		ret = pm_clk_resume(dev);
> +		if (ret) {
> +			dev_err(dev, "pm_clk_resume failed %d\n", ret);
> +			goto clk_err;
> +		};
> +	}
> +	return;
> +
> +clk_err:
> +	pm_clk_destroy(dev);
>  }
>  
> -static int keystone_pm_runtime_resume(struct device *dev)
> +void keystone_pm_domain_detach_dev(struct device *dev)
>  {
>  	dev_dbg(dev, "%s\n", __func__);
> -
> -	pm_clk_resume(dev);
> -
> -	return pm_generic_runtime_resume(dev);
> +	pm_clk_destroy(dev);
>  }
> -#endif
>  
> -static struct dev_pm_domain keystone_pm_domain = {
> -	.ops = {
> -		SET_RUNTIME_PM_OPS(keystone_pm_runtime_suspend,
> -				   keystone_pm_runtime_resume, NULL)
> -		USE_PLATFORM_PM_SLEEP_OPS
> +static const struct keystone_domain keystone_domain = {
> +	.base = {
> +		.name = "keystone",
> +		.attach_dev = keystone_pm_domain_attach_dev,
> +		.detach_dev = keystone_pm_domain_detach_dev,
> +		.dev_ops = {
> +			.stop = pm_clk_suspend,
> +			.start = pm_clk_resume,
> +		},
> +		.power_off_latency_ns = 25000,
> +		.power_on_latency_ns = 2000000,
Did you cook up these numbers ?

Other than that patch looks fine to me. If Kevin is happy
with overall approach then we can proceed with this.

Regards,
Santosh