Re: [PATCH v5 7/7] arm: dts: qcom: Add idle states device nodes for 8974

[Lina Iyer <lina.iyer@linaro.org>]

On Thu, Sep 04 2014 at 16:36 -0600, Lina Iyer wrote:
>Add allowable C-States for each cpu using the cpu-idle-states node.
>ARM spec dictates WFI as the default idle state at 0. Support standalone
>power collapse (power down that does not affect any SoC idle states) for
>each cpu.
>
>Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
>---
> arch/arm/boot/dts/qcom-msm8974.dtsi | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
>diff --git a/arch/arm/boot/dts/qcom-msm8974.dtsi b/arch/arm/boot/dts/qcom-msm8974.dtsi
>index 0580bc2..041c8b6 100644
>--- a/arch/arm/boot/dts/qcom-msm8974.dtsi
>+++ b/arch/arm/boot/dts/qcom-msm8974.dtsi
>@@ -21,6 +21,7 @@
> 			reg = <0>;
> 			next-level-cache = <&L2>;
> 			qcom,acc = <&acc0>;
>+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
> 		};
>
> 		CPU1: cpu@1 {
>@@ -30,6 +31,7 @@
> 			reg = <1>;
> 			next-level-cache = <&L2>;
> 			qcom,acc = <&acc1>;
>+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
> 		};
>
> 		CPU2: cpu@2 {
>@@ -39,6 +41,7 @@
> 			reg = <2>;
> 			next-level-cache = <&L2>;
> 			qcom,acc = <&acc2>;
>+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
> 		};
>
> 		CPU3: cpu@3 {
>@@ -48,6 +51,7 @@
> 			reg = <3>;
> 			next-level-cache = <&L2>;
> 			qcom,acc = <&acc3>;
>+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
> 		};
>
> 		L2: l2-cache {
>@@ -55,6 +59,22 @@
> 			cache-level = <2>;
> 			qcom,saw = <&saw_l2>;
> 		};
>+
>+		idle-states {
>+			CPU_WFI: cpu-idle-state-0 {
I will rename the device node name to something more relevant. The name is
used as the idle-state name.
>+				compatible = "qcom,idle-state-wfi", "arm,idle-state";
>+				entry-latency-us = <1>;
>+				exit-latency-us = <1>;
>+				min-residency-us = <2>;
>+			};
>+
>+			CPU_SPC: cpu-idle-state-1 {
>+				compatible = "qcom,idle-state-spc", "arm,idle-state";
>+				entry-latency-us = <150>;
>+				exit-latency-us = <200>;
>+				min-residency-us = <2000>;
>+			};
>+		};
> 	};
>
> 	cpu-pmu {
>-- 
>1.9.1
>