[PATCH v5 6/9] drm/vc4: hdmi: Store pixel frequency in the connector state

[Dave Stevenson]

Hi Maxime

On Mon, 7 Dec 2020 at 15:57, Maxime Ripard <maxime at cerno.tech> wrote:
>
> The pixel rate is for now quite simple to compute, but with more features
> (30 and 36 bits output, YUV output, etc.) will depend on a bunch of
> connectors properties.
>
> Let's store the rate we have to run the pixel clock at in our custom
> connector state, and compute it in atomic_check.
>
> Signed-off-by: Maxime Ripard <maxime at cerno.tech>

Reviewed-by: Dave Stevenson <dave.stevenson at raspberrypi.com>

> ---
>  drivers/gpu/drm/vc4/vc4_hdmi.c | 26 +++++++++++++++++++++++++-
>  drivers/gpu/drm/vc4/vc4_hdmi.h |  1 +
>  2 files changed, 26 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> index 744396c8dcb9..83699105c7a5 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> @@ -194,6 +194,7 @@ vc4_hdmi_connector_duplicate_state(struct drm_connector *connector)
>         if (!new_state)
>                 return NULL;
>
> +       new_state->pixel_rate = vc4_state->pixel_rate;
>         __drm_atomic_helper_connector_duplicate_state(connector, &new_state->base);
>
>         return &new_state->base;
> @@ -611,9 +612,29 @@ static void vc4_hdmi_recenter_fifo(struct vc4_hdmi *vc4_hdmi)
>                   "VC4_HDMI_FIFO_CTL_RECENTER_DONE");
>  }
>
> +static struct drm_connector_state *
> +vc4_hdmi_encoder_get_connector_state(struct drm_encoder *encoder,
> +                                    struct drm_atomic_state *state)
> +{
> +       struct drm_connector_state *conn_state;
> +       struct drm_connector *connector;
> +       unsigned int i;
> +
> +       for_each_new_connector_in_state(state, connector, conn_state, i) {
> +               if (conn_state->best_encoder == encoder)
> +                       return conn_state;
> +       }
> +
> +       return NULL;
> +}
> +
>  static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
>                                                 struct drm_atomic_state *state)
>  {
> +       struct drm_connector_state *conn_state =
> +               vc4_hdmi_encoder_get_connector_state(encoder, state);
> +       struct vc4_hdmi_connector_state *vc4_conn_state =
> +               conn_state_to_vc4_hdmi_conn_state(conn_state);
>         struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
>         struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
>         unsigned long pixel_rate, hsm_rate;
> @@ -625,7 +646,7 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
>                 return;
>         }
>
> -       pixel_rate = mode->clock * 1000 * ((mode->flags & DRM_MODE_FLAG_DBLCLK) ? 2 : 1);
> +       pixel_rate = vc4_conn_state->pixel_rate;
>         ret = clk_set_rate(vc4_hdmi->pixel_clock, pixel_rate);
>         if (ret) {
>                 DRM_ERROR("Failed to set pixel clock rate: %d\n", ret);
> @@ -797,6 +818,7 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
>                                          struct drm_crtc_state *crtc_state,
>                                          struct drm_connector_state *conn_state)
>  {
> +       struct vc4_hdmi_connector_state *vc4_state = conn_state_to_vc4_hdmi_conn_state(conn_state);
>         struct drm_display_mode *mode = &crtc_state->adjusted_mode;
>         struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
>         unsigned long long pixel_rate = mode->clock * 1000;
> @@ -827,6 +849,8 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
>         if (pixel_rate > vc4_hdmi->variant->max_pixel_clock)
>                 return -EINVAL;
>
> +       vc4_state->pixel_rate = pixel_rate;
> +
>         return 0;
>  }
>
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
> index 2cf5362052e2..bca6943de884 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.h
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
> @@ -182,6 +182,7 @@ encoder_to_vc4_hdmi(struct drm_encoder *encoder)
>
>  struct vc4_hdmi_connector_state {
>         struct drm_connector_state      base;
> +       unsigned long long              pixel_rate;
>  };
>
>  static inline struct vc4_hdmi_connector_state *
> --
> 2.28.0
>