[PATCH v5 7/7] arm: dts: qcom: Add idle states device nodes for 8974
Lina Iyer
lina.iyer at linaro.org
Fri Sep 5 12:59:37 PDT 2014
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 at 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 at 1 {
>@@ -30,6 +31,7 @@
> reg = <1>;
> next-level-cache = <&L2>;
> qcom,acc = <&acc1>;
>+ cpu-idle-states = <&CPU_WFI &CPU_SPC>;
> };
>
> CPU2: cpu at 2 {
>@@ -39,6 +41,7 @@
> reg = <2>;
> next-level-cache = <&L2>;
> qcom,acc = <&acc2>;
>+ cpu-idle-states = <&CPU_WFI &CPU_SPC>;
> };
>
> CPU3: cpu at 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
>
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