Re: [PATCH] arm64: dts: qcom: sm8150: Add support for deep CPU cluster idle

From: Bjorn Andersson
Date: Tue Jan 05 2021 - 18:06:32 EST


On Tue 05 Jan 12:10 PST 2021, Danny Lin wrote:

> This commit adds support for deep idling of the entire unified DynamIQ
> CPU cluster on sm8150. In this idle state, the LLCC (Last-Level Cache
> Controller) is powered off and the AOP (Always-On Processor) enters a
> low-power sleep state.
>
> I'm not sure what the per-CPU 0x400000f4 idle state previously
> contributed by Qualcomm as the "cluster sleep" state is, but the
> downstream kernel has no such state. The real deep cluster idle state
> is 0x41000c244, composed of:
>
> Cluster idle state: (0xc24) << 4 = 0xc240
> Is reset state: 1 << 30 = 0x40000000
> Affinity level: 1 << 24 = 0x1000000
> CPU idle state: 0x4 (power collapse)
>
> This setup can be replicated with the PSCI power domain cpuidle driver,
> which utilizes OSI to enter cluster idle when the last active CPU
> enters idle.
>
> The cluster idle state cannot be used as a plain cpuidle state because
> it requires that all CPUs in the cluster are idling.
>

This looks quite reasonable to me.

@Ulf, this seems to be the first attempt at wiring up the domain idle
pieces upstream, would you mind having a look?

The SM8150 pretty much identical to RB3 in this regard.

Regards,
Bjorn

> Signed-off-by: Danny Lin <danny@xxxxxxxxxxx>
> ---
> arch/arm64/boot/dts/qcom/sm8150.dtsi | 91 ++++++++++++++++++++++------
> 1 file changed, 73 insertions(+), 18 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/qcom/sm8150.dtsi b/arch/arm64/boot/dts/qcom/sm8150.dtsi
> index 309e00b6fa44..8956c6986744 100644
> --- a/arch/arm64/boot/dts/qcom/sm8150.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8150.dtsi
> @@ -52,10 +52,10 @@ CPU0: cpu@0 {
> enable-method = "psci";
> capacity-dmips-mhz = <488>;
> dynamic-power-coefficient = <232>;
> - cpu-idle-states = <&LITTLE_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_0>;
> qcom,freq-domain = <&cpufreq_hw 0>;
> + power-domains = <&CPU_PD0>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_0: l2-cache {
> compatible = "cache";
> @@ -73,10 +73,10 @@ CPU1: cpu@100 {
> enable-method = "psci";
> capacity-dmips-mhz = <488>;
> dynamic-power-coefficient = <232>;
> - cpu-idle-states = <&LITTLE_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_100>;
> qcom,freq-domain = <&cpufreq_hw 0>;
> + power-domains = <&CPU_PD1>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_100: l2-cache {
> compatible = "cache";
> @@ -92,10 +92,10 @@ CPU2: cpu@200 {
> enable-method = "psci";
> capacity-dmips-mhz = <488>;
> dynamic-power-coefficient = <232>;
> - cpu-idle-states = <&LITTLE_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_200>;
> qcom,freq-domain = <&cpufreq_hw 0>;
> + power-domains = <&CPU_PD2>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_200: l2-cache {
> compatible = "cache";
> @@ -110,10 +110,10 @@ CPU3: cpu@300 {
> enable-method = "psci";
> capacity-dmips-mhz = <488>;
> dynamic-power-coefficient = <232>;
> - cpu-idle-states = <&LITTLE_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_300>;
> qcom,freq-domain = <&cpufreq_hw 0>;
> + power-domains = <&CPU_PD3>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_300: l2-cache {
> compatible = "cache";
> @@ -128,10 +128,10 @@ CPU4: cpu@400 {
> enable-method = "psci";
> capacity-dmips-mhz = <1024>;
> dynamic-power-coefficient = <369>;
> - cpu-idle-states = <&BIG_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_400>;
> qcom,freq-domain = <&cpufreq_hw 1>;
> + power-domains = <&CPU_PD4>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_400: l2-cache {
> compatible = "cache";
> @@ -146,10 +146,10 @@ CPU5: cpu@500 {
> enable-method = "psci";
> capacity-dmips-mhz = <1024>;
> dynamic-power-coefficient = <369>;
> - cpu-idle-states = <&BIG_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_500>;
> qcom,freq-domain = <&cpufreq_hw 1>;
> + power-domains = <&CPU_PD5>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_500: l2-cache {
> compatible = "cache";
> @@ -164,10 +164,10 @@ CPU6: cpu@600 {
> enable-method = "psci";
> capacity-dmips-mhz = <1024>;
> dynamic-power-coefficient = <369>;
> - cpu-idle-states = <&BIG_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_600>;
> qcom,freq-domain = <&cpufreq_hw 1>;
> + power-domains = <&CPU_PD6>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_600: l2-cache {
> compatible = "cache";
> @@ -182,10 +182,10 @@ CPU7: cpu@700 {
> enable-method = "psci";
> capacity-dmips-mhz = <1024>;
> dynamic-power-coefficient = <421>;
> - cpu-idle-states = <&BIG_CPU_SLEEP_0
> - &CLUSTER_SLEEP_0>;
> next-level-cache = <&L2_700>;
> qcom,freq-domain = <&cpufreq_hw 2>;
> + power-domains = <&CPU_PD7>;
> + power-domain-names = "psci";
> #cooling-cells = <2>;
> L2_700: l2-cache {
> compatible = "cache";
> @@ -251,11 +251,13 @@ BIG_CPU_SLEEP_0: cpu-sleep-1-0 {
> min-residency-us = <4488>;
> local-timer-stop;
> };
> + };
>
> + domain-idle-states {
> CLUSTER_SLEEP_0: cluster-sleep-0 {
> - compatible = "arm,idle-state";
> + compatible = "domain-idle-state";
> idle-state-name = "cluster-power-collapse";
> - arm,psci-suspend-param = <0x400000F4>;
> + arm,psci-suspend-param = <0x4100c244>;
> entry-latency-us = <3263>;
> exit-latency-us = <6562>;
> min-residency-us = <9987>;
> @@ -291,6 +293,59 @@ pmu {
> psci {
> compatible = "arm,psci-1.0";
> method = "smc";
> +
> + CPU_PD0: cpu0 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&LITTLE_CPU_SLEEP_0>;
> + };
> +
> + CPU_PD1: cpu1 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&LITTLE_CPU_SLEEP_0>;
> + };
> +
> + CPU_PD2: cpu2 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&LITTLE_CPU_SLEEP_0>;
> + };
> +
> + CPU_PD3: cpu3 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&LITTLE_CPU_SLEEP_0>;
> + };
> +
> + CPU_PD4: cpu4 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&BIG_CPU_SLEEP_0>;
> + };
> +
> + CPU_PD5: cpu5 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&BIG_CPU_SLEEP_0>;
> + };
> +
> + CPU_PD6: cpu6 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&BIG_CPU_SLEEP_0>;
> + };
> +
> + CPU_PD7: cpu7 {
> + #power-domain-cells = <0>;
> + power-domains = <&CLUSTER_PD>;
> + domain-idle-states = <&BIG_CPU_SLEEP_0>;
> + };
> +
> + CLUSTER_PD: cpu-cluster0 {
> + #power-domain-cells = <0>;
> + domain-idle-states = <&CLUSTER_SLEEP_0>;
> + };
> };
>
> reserved-memory {
> --
> 2.29.2
>