Re: [PATCH] arm64: dts: sdm845: Add PSCI cpuidle low power states

From: Doug Anderson
Date: Tue Oct 23 2018 - 14:36:20 EST


On Mon, Oct 15, 2018 at 10:02 AM Raju P.L.S.S.S.N
<rplsssn@xxxxxxxxxxxxxx> wrote:
> + idle-states {
> + entry-method = "psci";
> +
> + C0_CPU_SPC: c0_spc {

nit: all these nodes should have dashes instead of spaces in the node
names (labels can still have spaces). AKA:

C0_CPU_SPC: c0-spc {

> + compatible = "arm,idle-state";
> + arm,psci-suspend-param = <0x40000003>;
> + entry-latency-us = <350>;
> + exit-latency-us = <461>;
> + min-residency-us = <1890>;
> + local-timer-stop;
> + idle-state-name = "pc";

It seems weird that the idle state with the node name "spc" has the
name "pc" and the idle state with the node name "pc" has the name
"rail pc". Can this be more consistent or is there a reason why they
need to be mismatched?

Also: AAHTUFSWDKWTM (acronyms are hard to understand for someone who
doesn't know what they mean). If you really need to use an the
acronyms "PC" and "SPC" please document them somewhere. In the very
least the commit message, but having a comment in the file is good
too. ...or (even better) don't use the acronym and spell out what
you're talking about. Please correct me if I'm wrong, but I don't
think it's obvious what the "PC" and "SPC" idle states mean.