Re: [PATCH V5 5/5] arm64: dts: imx8mm: Enable cpu-idle driver

[Daniel Lezcano]

Hi Anson,

sorry for the late review, I've been pretty busy.

If Shawn is ok, I can pick the patches 1-4 in my tree and then this one
after you fix the comments below.

On 10/07/2019 08:30, Anson.Huang@xxxxxxx wrote:

[ ... ]

> +		idle-states {
> +			entry-method = "psci";
> +
> +			cpu_sleep_wait: cpu-sleep-wait {

Is that a retention state or a powerdown? It is preferable to change the
name to the idle state naming convention given in the PSCI documentation
[1] page 16-17


> +				compatible = "arm,idle-state";
> +				arm,psci-suspend-param = <0x0010033>;
> +				local-timer-stop;
> +				entry-latency-us = <1000>;
> +				exit-latency-us = <700>;
> +				min-residency-us = <2700>;
> +				wakeup-latency-us = <1500>;

It is pointless to specify the entry + exit *and* the wakeup-latency [2].

Thanks

  -- Daniel

[1]
http://infocenter.arm.com/help/topic/com.arm.doc.den0022d/Power_State_Coordination_Interface_PDD_v1_1_DEN0022D.pdf

[2]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/cpuidle/dt_idle_states.c#n41



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