Re: [PATCH v2 7/7, RFC]: drm/panfrost: devfreq: Add support for 2 regulators

[Rob Herring]

On Tue, Jan 7, 2020 at 11:24 PM Nicolas Boichat <drinkcat@xxxxxxxxxxxx> wrote:
>
> The Bifrost GPU on MT8183 uses 2 regulators (core and SRAM) for
> devfreq, and provides OPP table with 2 sets of voltages.
>
> TODO: This is incomplete as we'll need add support for setting
> a pair of voltages as well.
>
> Signed-off-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/panfrost/panfrost_devfreq.c | 18 ++++++++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_device.h  |  2 ++
>  2 files changed, 20 insertions(+)
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> index 413987038fbfccb..5eb0effded7eb09 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> @@ -79,6 +79,22 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
>         struct devfreq *devfreq;
>         struct thermal_cooling_device *cooling;
>
> +       /* If we have 2 regulator, we need an OPP table with 2 voltages. */
> +       if (pfdev->regulator_sram) {
> +               const char * const reg_names[] = { "mali", "sram" };
> +
> +               pfdev->devfreq.dev_opp_table =
> +                       dev_pm_opp_set_regulators(dev,
> +                                       reg_names, ARRAY_SIZE(reg_names));
> +               if (IS_ERR(pfdev->devfreq.dev_opp_table)) {
> +                       ret = PTR_ERR(pfdev->devfreq.dev_opp_table);
> +                       pfdev->devfreq.dev_opp_table = NULL;
> +                       dev_err(dev,
> +                               "Failed to init devfreq opp table: %d\n", ret);
> +                       return ret;
> +               }
> +       }
> +
>         ret = dev_pm_opp_of_add_table(dev);
>         if (ret == -ENODEV) /* Optional, continue without devfreq */
>                 return 0;
> @@ -119,6 +135,8 @@ void panfrost_devfreq_fini(struct panfrost_device *pfdev)
>         if (pfdev->devfreq.cooling)
>                 devfreq_cooling_unregister(pfdev->devfreq.cooling);
>         dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
> +       if (pfdev->devfreq.dev_opp_table)
> +               dev_pm_opp_put_regulators(pfdev->devfreq.dev_opp_table);
>  }
>
>  void panfrost_devfreq_resume(struct panfrost_device *pfdev)
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h
> index 92d471676fc7823..581da3fe5df8b17 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.h
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.h
> @@ -91,10 +91,12 @@ struct panfrost_device {
>         struct {
>                 struct devfreq *devfreq;
>                 struct thermal_cooling_device *cooling;
> +               struct opp_table *dev_opp_table;
>                 ktime_t busy_time;
>                 ktime_t idle_time;
>                 ktime_t time_last_update;
>                 atomic_t busy_count;
> +               struct panfrost_devfreq_slot slot[NUM_JOB_SLOTS];

?? Left over from some rebase?

Rob