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

[Marc Gonzalez]

On 21/05/2019 11:35, Amit Kucheria 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 {


NB: this patch does not apply cleanly to v5.2-rc1  ;-)

86f93c93dd50 arm64: dts: msm8998: efficiency is not valid property

commit 86f93c93dd5005f0aeb8ce84c2113e21a6006c7d
Author:     Amit Kucheria <amit.kucheria@xxxxxxxxxx>
AuthorDate: Fri Mar 29 15:42:08 2019 +0530
Commit:     Andy Gross <agross@xxxxxxxxxx>
CommitDate: Tue Apr 9 23:08:17 2019 -0500

After manually fixing up the trivial conflict, the DTB builds without errors.

I then enable
+CONFIG_CPU_IDLE=y
+CONFIG_ARM_CPUIDLE=y

(because I'm using a board-specific tiny defconfig)

And... the system starts to boot, hangs a few seconds, then silently reboots:

scsi 0:0:0:3: Direct-Access     SAMSUNG  KLUBG4G1CE-B0B1  0800 PQ: 0 ANSI: 6
sd 0:0:0:1: [sdb] 16384-byte physical blocks
sd 0:0:0:2: [sdc] 2048 4096-byte logical blocks: (8.39 MB/8.00 MiB)
sd 0:0:0:2: [sdc] 16384-byte physical blocks

Format: Log Type - Time(microsec) - Message - Optional Info
Log Type: B - Since Boot(Power On Reset),  D - Delta,  S - Statistic
S - QC_IMAGE_VERSION_STRING=BOOT.XF.1.2.2-00157-M8998LZB-1
S - IMAGE_VARIANT_STRING=Msm8998LA


Looks like the "helpful" behavior of the secure OS...

Regards.