Re: [PATCH V2 07/15] cpufreq: mediatek: Add opp notification for SVS support

Kevin Hilman
2022-04-08T20:29:15Z

Rex-BC Chen <rex-bc.chen@mediatek.com> writes:

> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
>
> The Smart Voltage Scaling (SVS) is a hardware which calculates suitable
> SVS bank voltages to OPP voltage table.
>
> When the SVS is enabled, cpufreq should listen to opp notification and do
> proper actions when receiving events of disable and voltage adjustment.

So listenting for OPP notifications should be done only when SVS is enabled...

[...]

> static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
> {
> struct device *cpu_dev;
> @@ -392,6 +455,17 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
> info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
> dev_pm_opp_put(opp);
>
> + info->opp_cpu = cpu;
> + info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier;
> + ret = dev_pm_opp_register_notifier(cpu_dev, &info->opp_nb);

...but here youlisten to OPP notifications unconditionally. Seems there
should be a check whether SVS is enabled before deciding to register.

Kevin