[PATCH v2 13/15] arm64: dts: qcom: msm8916: Add CPU ACC and SAW/SPM

Stephan Gerhold stephan at gerhold.net
Mon Oct 4 13:49:53 PDT 2021


Add the device tree nodes necessary for SMP bring-up and cpuidle
without PSCI on ARM32. The hardware is typically controlled by the
PSCI implementation in the TrustZone firmware and is therefore marked
as status = "reserved" by default (from the device tree specification):

  "Indicates that the device is operational, but should not be used.
   Typically this is used for devices that are controlled by another
   software component, such as platform firmware."

Since this is part of the MSM8916 SoC it should be added to msm8916.dtsi
but in practice these nodes should only get enabled via an extra include
on ARM32.

This is necessary for some devices with signed firmware which is missing
both ARM64 and PSCI support and can therefore only boot ARM32 kernels.

Signed-off-by: Stephan Gerhold <stephan at gerhold.net>
---
Changes in v2: None.
---
 arch/arm64/boot/dts/qcom/msm8916.dtsi | 56 +++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/msm8916.dtsi b/arch/arm64/boot/dts/qcom/msm8916.dtsi
index 6b06b387b021..3e7e5c9e6f1b 100644
--- a/arch/arm64/boot/dts/qcom/msm8916.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8916.dtsi
@@ -124,6 +124,8 @@ CPU0: cpu at 0 {
 			#cooling-cells = <2>;
 			power-domains = <&CPU_PD0>;
 			power-domain-names = "psci";
+			qcom,acc = <&cpu0_acc>;
+			qcom,saw = <&cpu0_saw>;
 		};
 
 		CPU1: cpu at 1 {
@@ -137,6 +139,8 @@ CPU1: cpu at 1 {
 			#cooling-cells = <2>;
 			power-domains = <&CPU_PD1>;
 			power-domain-names = "psci";
+			qcom,acc = <&cpu1_acc>;
+			qcom,saw = <&cpu1_saw>;
 		};
 
 		CPU2: cpu at 2 {
@@ -150,6 +154,8 @@ CPU2: cpu at 2 {
 			#cooling-cells = <2>;
 			power-domains = <&CPU_PD2>;
 			power-domain-names = "psci";
+			qcom,acc = <&cpu2_acc>;
+			qcom,saw = <&cpu2_saw>;
 		};
 
 		CPU3: cpu at 3 {
@@ -163,6 +169,8 @@ CPU3: cpu at 3 {
 			#cooling-cells = <2>;
 			power-domains = <&CPU_PD3>;
 			power-domain-names = "psci";
+			qcom,acc = <&cpu3_acc>;
+			qcom,saw = <&cpu3_saw>;
 		};
 
 		L2_0: l2-cache {
@@ -1877,6 +1885,54 @@ frame at b028000 {
 				status = "disabled";
 			};
 		};
+
+		cpu0_acc: power-manager at b088000 {
+			compatible = "qcom,msm8916-acc";
+			reg = <0x0b088000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
+
+		cpu0_saw: power-manager at b089000 {
+			compatible = "qcom,msm8916-saw2-v3.0-cpu", "qcom,saw2";
+			reg = <0x0b089000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
+
+		cpu1_acc: power-manager at b098000 {
+			compatible = "qcom,msm8916-acc";
+			reg = <0x0b098000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
+
+		cpu1_saw: power-manager at b099000 {
+			compatible = "qcom,msm8916-saw2-v3.0-cpu", "qcom,saw2";
+			reg = <0x0b099000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
+
+		cpu2_acc: power-manager at b0a8000 {
+			compatible = "qcom,msm8916-acc";
+			reg = <0x0b0a8000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
+
+		cpu2_saw: power-manager at b0a9000 {
+			compatible = "qcom,msm8916-saw2-v3.0-cpu", "qcom,saw2";
+			reg = <0x0b0a9000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
+
+		cpu3_acc: power-manager at b0b8000 {
+			compatible = "qcom,msm8916-acc";
+			reg = <0x0b0b8000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
+
+		cpu3_saw: power-manager at b0b9000 {
+			compatible = "qcom,msm8916-saw2-v3.0-cpu", "qcom,saw2";
+			reg = <0x0b0b9000 0x1000>;
+			status = "reserved"; /* Controlled by PSCI firmware */
+		};
 	};
 
 	thermal-zones {
-- 
2.33.0




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