Hi Maxime
On Thu, 29 Oct 2020 at 12:25, Maxime Ripard <maxime@xxxxxxxxxx> wrote:
>
> The HDMI controller cannot go above a certain pixel rate limit depending on
> the generations, but that limit is only enforced in mode_valid at the
> moment, which means that we won't advertise modes that exceed that limit,
> but the userspace is still free to try to setup a mode that would.
>
> Implement atomic_check to make sure we check it in that scenario too.
>
> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
Reviewed-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
> ---
>
> Changes from v1:
> - Added that patch to resolve a conflict
> ---
> drivers/gpu/drm/vc4/vc4_hdmi.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> index e8f99e290655..3d0338822cd2 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> @@ -760,6 +760,20 @@ static void vc4_hdmi_encoder_enable(struct drm_encoder *encoder)
> {
> }
>
> +static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
> + struct drm_crtc_state *crtc_state,
> + struct drm_connector_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;
> +
> + if (pixel_rate > vc4_hdmi->variant->max_pixel_clock)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> static enum drm_mode_status
> vc4_hdmi_encoder_mode_valid(struct drm_encoder *encoder,
> const struct drm_display_mode *mode)
> @@ -773,6 +787,7 @@ vc4_hdmi_encoder_mode_valid(struct drm_encoder *encoder,
> }
>
> static const struct drm_encoder_helper_funcs vc4_hdmi_encoder_helper_funcs = {
> + .atomic_check = vc4_hdmi_encoder_atomic_check,
> .mode_valid = vc4_hdmi_encoder_mode_valid,
> .disable = vc4_hdmi_encoder_disable,
> .enable = vc4_hdmi_encoder_enable,
> --
> 2.26.2
>
