Re: [PATCH V2 06/15] cpufreq: mediatek: Record previous target vproc value

Viresh Kumar
2022-04-11T03:27:13Z

On 08-04-22, 12:58, Rex-BC Chen wrote:
> From: Jia-Wei Chang <jia-wei.chang@mediatek.com>
>
> We found the buck voltage may not be exactly the same with what we set
> because CPU may share the same buck with other module.
> Therefore, we need to record the previous desired value instead of reading
> it from regulators.
>
> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
> ---
> drivers/cpufreq/mediatek-cpufreq.c | 31 +++++++++++++++++++-----------
> 1 file changed, 20 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
> index dc4a87e68940..472f4de29e5f 100644
> --- a/drivers/cpufreq/mediatek-cpufreq.c
> +++ b/drivers/cpufreq/mediatek-cpufreq.c
> @@ -40,6 +40,7 @@ struct mtk_cpu_dvfs_info {
> struct list_head list_head;
> int intermediate_voltage;
> bool need_voltage_tracking;
> + int old_vproc;

I like prev_vproc better somehow, but it is up to you to name it :)

> };
>
> static LIST_HEAD(dvfs_info_list);
> @@ -190,11 +191,17 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info,
>
> static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc)
> {
> + int ret;
> +
> if (info->need_voltage_tracking)
> - return mtk_cpufreq_voltage_tracking(info, vproc);
> + ret = mtk_cpufreq_voltage_tracking(info, vproc);
> else
> - return regulator_set_voltage(info->proc_reg, vproc,
> - vproc + VOLT_TOL);
> + ret = regulator_set_voltage(info->proc_reg, vproc,
> + MAX_VOLT_LIMIT);
> + if (!ret)
> + info->old_vproc = vproc;
> +
> + return ret;
> }
>
> static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
> @@ -211,15 +218,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
>
> inter_vproc = info->intermediate_voltage;
>
> - old_freq_hz = clk_get_rate(cpu_clk);
> - old_vproc = regulator_get_voltage(info->proc_reg);
> - if (old_vproc < 0) {
> - pr_err("%s: invalid Vproc value: %d\n", __func__, old_vproc);
> - return old_vproc;
> - }
> -

Why did you move it down from here? I think it was fine to error out
early if voltage isn't available.

> freq_hz = freq_table[index].frequency * 1000;
> -
> opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz);
> if (IS_ERR(opp)) {
> pr_err("cpu%d: failed to find OPP for %ld\n",
> @@ -229,6 +228,16 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
> vproc = dev_pm_opp_get_voltage(opp);
> dev_pm_opp_put(opp);
>
> + old_freq_hz = clk_get_rate(cpu_clk);
> + old_vproc = info->old_vproc;
> + if (old_vproc == 0)
> + old_vproc = regulator_get_voltage(info->proc_reg);
> + if (old_vproc < 0) {
> + dev_err(cpu_dev, "%s: invalid Vproc value: %d\n",
> + __func__, old_vproc);
> + return old_vproc;
> + }
> +
> /*
> * If the new voltage or the intermediate voltage is higher than the
> * current voltage, scale up voltage first.
> --
> 2.18.0

--
viresh