Re: [PATCH v2 7/9] arm64: dts: qcom: msm8998: Add PSCI cpuidle low power states

From: Jeffrey Hugo
Date: Tue Oct 01 2019 - 10:22:09 EST

On Mon, Sep 30, 2019 at 4:44 PM Amit Kucheria <amit.kucheria@xxxxxxxxxx> wrote:
>
> Can you try removing just the *SLEEP_1 states from the cpu-idle-states
> property? I want to understand if this is triggered just by the deeper
> C-state.

Still seeing the issue with just the SLEEP_0 states. For reference,
Bjorn suggested adding kpti=no to the command line, which also
appeared to have no effect on the issue.

>
> On Tue, Oct 1, 2019 at 3:50 AM Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx> wrote:
> >
> > Amit, the merged version of the below change causes a boot failure
> > (nasty hang, sometimes with RCU stalls) on the msm8998 laptops. Oddly
> > enough, it seems to be resolved if I remove the cpu-idle-states
> > property from one of the cpu nodes.
> >
> > I see no issues with the msm8998 MTP.
> >
> > Do you have any suggestions on how we might debug this?
> >
> > On Tue, May 21, 2019 at 3:38 AM Amit Kucheria <amit.kucheria@xxxxxxxxxx> wrote:
> > >
> > > Add device bindings for cpuidle states for cpu devices.
> > >
> > > Cc: Marc Gonzalez <marc.w.gonzalez@xxxxxxx>
> > > Signed-off-by: Amit Kucheria <amit.kucheria@xxxxxxxxxx>
> > > Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> > > ---
> > > arch/arm64/boot/dts/qcom/msm8998.dtsi | 50 +++++++++++++++++++++++++++
> > > 1 file changed, 50 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/qcom/msm8998.dtsi b/arch/arm64/boot/dts/qcom/msm8998.dtsi
> > > index 3fd0769fe648..54810980fcf9 100644
> > > --- a/arch/arm64/boot/dts/qcom/msm8998.dtsi
> > > +++ b/arch/arm64/boot/dts/qcom/msm8998.dtsi
> > > @@ -78,6 +78,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x0>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&LITTLE_CPU_SLEEP_0 &LITTLE_CPU_SLEEP_1>;
> > > efficiency = <1024>;
> > > next-level-cache = <&L2_0>;
> > > L2_0: l2-cache {
> > > @@ -97,6 +98,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x1>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&LITTLE_CPU_SLEEP_0 &LITTLE_CPU_SLEEP_1>;
> > > efficiency = <1024>;
> > > next-level-cache = <&L2_0>;
> > > L1_I_1: l1-icache {
> > > @@ -112,6 +114,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x2>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&LITTLE_CPU_SLEEP_0 &LITTLE_CPU_SLEEP_1>;
> > > efficiency = <1024>;
> > > next-level-cache = <&L2_0>;
> > > L1_I_2: l1-icache {
> > > @@ -127,6 +130,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x3>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&LITTLE_CPU_SLEEP_0 &LITTLE_CPU_SLEEP_1>;
> > > efficiency = <1024>;
> > > next-level-cache = <&L2_0>;
> > > L1_I_3: l1-icache {
> > > @@ -142,6 +146,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x100>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&BIG_CPU_SLEEP_0 &BIG_CPU_SLEEP_1>;
> > > efficiency = <1536>;
> > > next-level-cache = <&L2_1>;
> > > L2_1: l2-cache {
> > > @@ -161,6 +166,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x101>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&BIG_CPU_SLEEP_0 &BIG_CPU_SLEEP_1>;
> > > efficiency = <1536>;
> > > next-level-cache = <&L2_1>;
> > > L1_I_101: l1-icache {
> > > @@ -176,6 +182,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x102>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&BIG_CPU_SLEEP_0 &BIG_CPU_SLEEP_1>;
> > > efficiency = <1536>;
> > > next-level-cache = <&L2_1>;
> > > L1_I_102: l1-icache {
> > > @@ -191,6 +198,7 @@
> > > compatible = "arm,armv8";
> > > reg = <0x0 0x103>;
> > > enable-method = "psci";
> > > + cpu-idle-states = <&BIG_CPU_SLEEP_0 &BIG_CPU_SLEEP_1>;
> > > efficiency = <1536>;
> > > next-level-cache = <&L2_1>;
> > > L1_I_103: l1-icache {
> > > @@ -238,6 +246,48 @@
> > > };
> > > };
> > > };
> > > +
> > > + idle-states {
> > > + entry-method = "psci";
> > > +
> > > + LITTLE_CPU_SLEEP_0: cpu-sleep-0-0 {
> > > + compatible = "arm,idle-state";
> > > + idle-state-name = "little-retention";
> > > + arm,psci-suspend-param = <0x00000002>;
> > > + entry-latency-us = <43>;
> > > + exit-latency-us = <86>;
> > > + min-residency-us = <200>;
> > > + };
> > > +
> > > + LITTLE_CPU_SLEEP_1: cpu-sleep-0-1 {
> > > + compatible = "arm,idle-state";
> > > + idle-state-name = "little-power-collapse";
> > > + arm,psci-suspend-param = <0x00000003>;
> > > + entry-latency-us = <100>;
> > > + exit-latency-us = <612>;
> > > + min-residency-us = <1000>;
> > > + local-timer-stop;
> > > + };
> > > +
> > > + BIG_CPU_SLEEP_0: cpu-sleep-1-0 {
> > > + compatible = "arm,idle-state";
> > > + idle-state-name = "big-retention";
> > > + arm,psci-suspend-param = <0x00000002>;
> > > + entry-latency-us = <41>;
> > > + exit-latency-us = <82>;
> > > + min-residency-us = <200>;
> > > + };
> > > +
> > > + BIG_CPU_SLEEP_1: cpu-sleep-1-1 {
> > > + compatible = "arm,idle-state";
> > > + idle-state-name = "big-power-collapse";
> > > + arm,psci-suspend-param = <0x00000003>;
> > > + entry-latency-us = <100>;
> > > + exit-latency-us = <525>;
> > > + min-residency-us = <1000>;
> > > + local-timer-stop;
> > > + };
> > > + };
> > > };
> > >
> > > firmware {
> > > --
> > > 2.17.1
> > >