diff mbox series

[v2,1/2] drm/vc4: hdmi: Make sure our clock rate is within limits

Message ID 20201029122522.1917579-1-maxime@cerno.tech
State New, archived
Headers show
Series [v2,1/2] drm/vc4: hdmi: Make sure our clock rate is within limits | expand

Commit Message

Maxime Ripard Oct. 29, 2020, 12:25 p.m. UTC
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@cerno.tech>

---

Changes from v1:
  - Added that patch to resolve a conflict
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

Comments

Dave Stevenson Nov. 19, 2020, 11:19 a.m. UTC | #1
Hi Maxime

On Thu, 29 Oct 2020 at 12:25, Maxime Ripard <maxime@cerno.tech> 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@cerno.tech>

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

> ---
>
> 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
>
diff mbox series

Patch

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,