RE: [PATCH V3 3/3] arm64: dts: imx8mp: Add thermal zones support

[Anson Huang]

Hi, Amit

> Subject: Re: [PATCH V3 3/3] arm64: dts: imx8mp: Add thermal zones support
> 
> On Mon, Mar 23, 2020 at 6:05 PM Anson Huang <Anson.Huang@xxxxxxx>
> wrote:
> >
> > i.MX8MP has a TMU inside which supports two thermal zones, add support
> > for them.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> 
> 
> [snip]
> 
> >
> > +       thermal-zones {
> > +               cpu-thermal {
> > +                       polling-delay-passive = <250>;
> > +                       polling-delay = <2000>;
> > +                       thermal-sensors = <&tmu 0x0>;
> 
> No need for 0x0, just use 0

OK.

> 
> > +                       trips {
> > +                               cpu_alert0: trip0 {
> > +                                       temperature = <85000>;
> > +                                       hysteresis = <2000>;
> > +                                       type = "passive";
> > +                               };
> > +
> > +                               cpu_crit0: trip1 {
> > +                                       temperature = <95000>;
> > +                                       hysteresis = <2000>;
> > +                                       type = "critical";
> > +                               };
> > +                       };
> > +
> > +                       cooling-maps {
> > +                               map0 {
> > +                                       trip = <&cpu_alert0>;
> > +                                       cooling-device =
> > +                                               <&A53_0
> THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +                                               <&A53_1
> THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +                                               <&A53_2
> THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +                                               <&A53_3
> THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> > +                               };
> > +                       };
> > +               };
> > +
> > +               soc-thermal {
> > +                       polling-delay-passive = <250>;
> > +                       polling-delay = <2000>;
> > +                       thermal-sensors = <&tmu 0x1>;
> 
> No need for 0x1, just use 1

OK.

> 
> > +                       trips {
> > +                               soc_alert0: trip0 {
> > +                                       temperature = <85000>;
> > +                                       hysteresis = <2000>;
> > +                                       type = "passive";
> > +                               };
> > +
> > +                               soc_crit0: trip1 {
> > +                                       temperature = <95000>;
> > +                                       hysteresis = <2000>;
> > +                                       type = "critical";
> > +                               };
> > +                       };
> 
> You need a cooling-map here since you have a passive trip point.

Currently, there is no cooling map defined for soc thermal zone, the cpufreq cooling
is mapped to cpu thermal zone already, so do you think it is OK to leave it as no cooling
map, or it is better to put cpufreq cooling for soc thermal zone as well?


Thanks,
Anson