Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
In-Reply-To: <20200929171026.30551-1-khsieh@codeaurora.org>
References: <20200929171026.30551-1-khsieh@codeaurora.org>
Subject: Re: [PATCH] drm/msm/dp: add voltage corners voting support base on dp link rate
From:   Stephen Boyd <swboyd@chromium.org>
Cc:     tanmay@codeaurora.org, abhinavk@codeaurora.org,
        aravindh@codeaurora.org, khsieh@codeaurora.org, airlied@linux.ie,
        daniel@ffwll.ch, linux-arm-msm@vger.kernel.org,
        dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, rnayak@codeaurora.org
To:     Kuogee Hsieh <khsieh@codeaurora.org>, robdclark@gmail.com,
        sean@poorly.run
Date:   Wed, 30 Sep 2020 01:24:57 -0700
Message-ID: <160145429763.310579.786737478429183087@swboyd.mtv.corp.google.com>
User-Agent: alot/0.9.1
Precedence: bulk

Quoting Kuogee Hsieh (2020-09-29 10:10:26)
> Set link rate by using OPP set rate api so that CX level will be set
> accordingly base on the link rate.

s/base/based/

>=20
> Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
> ---
> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp=
_ctrl.c
> index 2e3e1917351f..e1595d829e04 100644
> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> @@ -1849,6 +1853,21 @@ struct dp_ctrl *dp_ctrl_get(struct device *dev, st=
ruct dp_link *link,
>                 return ERR_PTR(-ENOMEM);
>         }
> =20
> +       ctrl->opp_table =3D dev_pm_opp_set_clkname(dev, "ctrl_link");
> +
> +       if (IS_ERR(ctrl->opp_table)) {
> +               dev_err(dev, "invalid DP OPP table in device tree\n");
> +               ctrl->opp_table =3D NULL;
> +       } else {
> +               /* OPP table is optional */
> +               ret =3D dev_pm_opp_of_add_table(dev);
> +               if (ret && ret !=3D -ENODEV) {
> +                       dev_err(dev, "add DP OPP table\n");

This is debug noise right?

> +                       dev_pm_opp_put_clkname(ctrl->opp_table);
> +                       ctrl->opp_table =3D NULL;
> +               }
> +       }
> +
>         init_completion(&ctrl->idle_comp);
>         init_completion(&ctrl->video_comp);
> =20
> @@ -1864,6 +1883,18 @@ struct dp_ctrl *dp_ctrl_get(struct device *dev, st=
ruct dp_link *link,
>         return &ctrl->dp_ctrl;
>  }
> =20
> -void dp_ctrl_put(struct dp_ctrl *dp_ctrl)
> +void dp_ctrl_put(struct device *dev, struct dp_ctrl *dp_ctrl)
>  {
> +       struct dp_ctrl_private *ctrl;
> +
> +       if (!dp_ctrl)

Can this happen?

> +               return;
> +
> +       ctrl =3D container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
> +
> +       if (ctrl->opp_table !=3D NULL) {

This is usually written as

	if (ctrl->opp_table)

> +               dev_pm_opp_of_remove_table(dev);
> +               dev_pm_opp_put_clkname(ctrl->opp_table);
> +               ctrl->opp_table =3D NULL;
> +       }
>  }
> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.h b/drivers/gpu/drm/msm/dp/dp=
_ctrl.h
> index f60ba93c8678..19b412a93e02 100644
> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.h
> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.h
> @@ -31,6 +31,6 @@ struct dp_ctrl *dp_ctrl_get(struct device *dev, struct =
dp_link *link,
>                         struct dp_panel *panel, struct drm_dp_aux *aux,
>                         struct dp_power *power, struct dp_catalog *catalo=
g,
>                         struct dp_parser *parser);
> -void dp_ctrl_put(struct dp_ctrl *dp_ctrl);
> +void dp_ctrl_put(struct device *dev, struct dp_ctrl *dp_ctrl);

Is 'dev' not inside 'dp_ctrl'?

> =20
>  #endif /* _DP_CTRL_H_ */
> diff --git a/drivers/gpu/drm/msm/dp/dp_power.c b/drivers/gpu/drm/msm/dp/d=
p_power.c
> index 17c1fc6a2d44..3d75bf09e38f 100644
> --- a/drivers/gpu/drm/msm/dp/dp_power.c
> +++ b/drivers/gpu/drm/msm/dp/dp_power.c
> @@ -8,12 +8,14 @@
>  #include <linux/clk.h>
>  #include <linux/clk-provider.h>
>  #include <linux/regulator/consumer.h>
> +#include <linux/pm_opp.h>
>  #include "dp_power.h"
>  #include "msm_drv.h"
> =20
>  struct dp_power_private {
>         struct dp_parser *parser;
>         struct platform_device *pdev;
> +       struct device *dev;
>         struct clk *link_clk_src;
>         struct clk *pixel_provider;
>         struct clk *link_provider;
> @@ -148,18 +150,49 @@ static int dp_power_clk_deinit(struct dp_power_priv=
ate *power)
>         return 0;
>  }
> =20
> +static int dp_power_clk_set_link_rate(struct dp_power_private *power,
> +                       struct dss_clk *clk_arry, int num_clk, int enable)
> +{
> +       u32 rate;
> +       int i, rc =3D 0;
> +
> +       for (i =3D 0; i < num_clk; i++) {
> +               if (clk_arry[i].clk) {
> +                       if (clk_arry[i].type =3D=3D DSS_CLK_PCLK) {
> +                               if (enable)
> +                                       rate =3D clk_arry[i].rate;
> +                               else
> +                                       rate =3D 0;
> +
> +                               rc =3D dev_pm_opp_set_rate(power->dev, ra=
te);

Why do we keep going if rc is non-zero?

> +                       }
> +
> +               }
> +       }
> +       return rc;
> +}
> +
>  static int dp_power_clk_set_rate(struct dp_power_private *power,
>                 enum dp_pm_type module, bool enable)
>  {
>         int rc =3D 0;
>         struct dss_module_power *mp =3D &power->parser->mp[module];
> =20
> -       if (enable) {
> -               rc =3D msm_dss_clk_set_rate(mp->clk_config, mp->num_clk);
> +       if (module =3D=3D DP_CTRL_PM) {
> +               rc =3D dp_power_clk_set_link_rate(power, mp->clk_config, =
mp->num_clk, enable);
>                 if (rc) {
> -                       DRM_ERROR("failed to set clks rate.\n");
> +                       DRM_ERROR("failed to set link clks rate.\n");
>                         return rc;
>                 }
> +       } else {
> +
> +               if (enable) {
> +                       rc =3D msm_dss_clk_set_rate(mp->clk_config, mp->n=
um_clk);
> +                       if (rc) {
> +                               DRM_ERROR("failed to set clks rate.\n");

Not sure we need the period on these error messages.

> +                               return rc;
> +                       }
> +               }
>         }
> =20
>         rc =3D msm_dss_enable_clk(mp->clk_config, mp->num_clk, enable);
>=20
> base-commit: 3c0f462da069af12211901ddf26f7e16e6951d9b
> prerequisite-patch-id: a109eaf08147f50149ad661a58122b6745a52445

Can you rebase this on Rob's msm-next tree
(https://gitlab.freedesktop.org/drm/msm.git) and test? It doesn't apply
for me because I have the dp phy patch from there.