[PATCH v7 7/7] arm: dts: qcom: Add idle states device nodes for 8084

Lina Iyer lina.iyer at linaro.org
Fri Sep 26 17:58:15 PDT 2014


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-apq8084.dtsi | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/arch/arm/boot/dts/qcom-apq8084.dtsi b/arch/arm/boot/dts/qcom-apq8084.dtsi
index 3dda230..a1ea1c0 100644
--- a/arch/arm/boot/dts/qcom-apq8084.dtsi
+++ b/arch/arm/boot/dts/qcom-apq8084.dtsi
@@ -19,6 +19,7 @@
 			next-level-cache = <&L2>;
 			qcom,acc = <&acc0>;
 			qcom,saw = <&saw0>;
+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
 		};
 
 		cpu at 1 {
@@ -29,6 +30,7 @@
 			next-level-cache = <&L2>;
 			qcom,acc = <&acc1>;
 			qcom,saw = <&saw1>;
+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
 		};
 
 		cpu at 2 {
@@ -39,6 +41,7 @@
 			next-level-cache = <&L2>;
 			qcom,acc = <&acc2>;
 			qcom,saw = <&saw2>;
+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
 		};
 
 		cpu at 3 {
@@ -49,6 +52,7 @@
 			next-level-cache = <&L2>;
 			qcom,acc = <&acc3>;
 			qcom,saw = <&saw3>;
+			cpu-idle-states = <&CPU_WFI &CPU_SPC>;
 		};
 
 		L2: l2-cache {
@@ -56,6 +60,22 @@
 			cache-level = <2>;
 			qcom,saw = <&saw_l2>;
 		};
+
+		idle-states {
+			CPU_WFI: wfi {
+				compatible = "qcom,idle-state-wfi", "arm,idle-state";
+				entry-latency-us = <1>;
+				exit-latency-us = <1>;
+				min-residency-us = <2>;
+			};
+
+			CPU_SPC: spc {
+				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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