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

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

[Maxime Ripard]

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(+)

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

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH v2 2/2] drm/vc4: hdmi: Block odd horizontal timings

[Maxime Ripard]

The FIFO between the pixelvalve and the HDMI controller runs at 2 pixels
per clock cycle, and cannot deal with odd timings.

Let's reject any mode with such timings.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

---

Changes from v1:
  - s/broken/unsupported/
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 12 ++++++++++++
 drivers/gpu/drm/vc4/vc4_hdmi.h |  3 +++
 2 files changed, 15 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 3d0338822cd2..506c12454086 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -768,6 +768,11 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 	unsigned long long pixel_rate = mode->clock * 1000;
 
+	if (vc4_hdmi->variant->unsupported_odd_h_timings &&
+	    ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
+	     (mode->hsync_end % 2) || (mode->htotal % 2)))
+		return -EINVAL;
+
 	if (pixel_rate > vc4_hdmi->variant->max_pixel_clock)
 		return -EINVAL;
 
@@ -780,6 +785,11 @@ vc4_hdmi_encoder_mode_valid(struct drm_encoder *encoder,
 {
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 
+	if (vc4_hdmi->variant->unsupported_odd_h_timings &&
+	    ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
+	     (mode->hsync_end % 2) || (mode->htotal % 2)))
+		return MODE_H_ILLEGAL;
+
 	if ((mode->clock * 1000) > vc4_hdmi->variant->max_pixel_clock)
 		return MODE_CLOCK_HIGH;
 
@@ -1830,6 +1840,7 @@ static const struct vc4_hdmi_variant bcm2711_hdmi0_variant = {
 		PHY_LANE_2,
 		PHY_LANE_CK,
 	},
+	.unsupported_odd_h_timings	= true,
 
 	.init_resources		= vc5_hdmi_init_resources,
 	.csc_setup		= vc5_hdmi_csc_setup,
@@ -1855,6 +1866,7 @@ static const struct vc4_hdmi_variant bcm2711_hdmi1_variant = {
 		PHY_LANE_CK,
 		PHY_LANE_2,
 	},
+	.unsupported_odd_h_timings	= true,
 
 	.init_resources		= vc5_hdmi_init_resources,
 	.csc_setup		= vc5_hdmi_csc_setup,
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index 63c6f8bddf1d..6815e93b1a48 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -62,6 +62,9 @@ struct vc4_hdmi_variant {
 	 */
 	enum vc4_hdmi_phy_channel phy_lane_mapping[4];
 
+	/* The BCM2711 cannot deal with odd horizontal pixel timings */
+	bool unsupported_odd_h_timings;
+
 	/* Callback to get the resources (memory region, interrupts,
 	 * clocks, etc) for that variant.
 	 */
-- 
2.26.2

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH v2 2/2] drm/vc4: hdmi: Block odd horizontal timings

[Dave Stevenson]

Hi Maxime

Thanks for the rewording :-)

On Thu, 29 Oct 2020 at 12:25, Maxime Ripard <maxime@cerno.tech> wrote:
>
> The FIFO between the pixelvalve and the HDMI controller runs at 2 pixels
> per clock cycle, and cannot deal with odd timings.
>
> Let's reject any mode with such timings.
>
> Signed-off-by: Maxime Ripard <maxime@cerno.tech>

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

> ---
>
> Changes from v1:
>   - s/broken/unsupported/
> ---
>  drivers/gpu/drm/vc4/vc4_hdmi.c | 12 ++++++++++++
>  drivers/gpu/drm/vc4/vc4_hdmi.h |  3 +++
>  2 files changed, 15 insertions(+)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> index 3d0338822cd2..506c12454086 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> @@ -768,6 +768,11 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
>         struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
>         unsigned long long pixel_rate = mode->clock * 1000;
>
> +       if (vc4_hdmi->variant->unsupported_odd_h_timings &&
> +           ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
> +            (mode->hsync_end % 2) || (mode->htotal % 2)))
> +               return -EINVAL;
> +
>         if (pixel_rate > vc4_hdmi->variant->max_pixel_clock)
>                 return -EINVAL;
>
> @@ -780,6 +785,11 @@ vc4_hdmi_encoder_mode_valid(struct drm_encoder *encoder,
>  {
>         struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
>
> +       if (vc4_hdmi->variant->unsupported_odd_h_timings &&
> +           ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
> +            (mode->hsync_end % 2) || (mode->htotal % 2)))
> +               return MODE_H_ILLEGAL;
> +
>         if ((mode->clock * 1000) > vc4_hdmi->variant->max_pixel_clock)
>                 return MODE_CLOCK_HIGH;
>
> @@ -1830,6 +1840,7 @@ static const struct vc4_hdmi_variant bcm2711_hdmi0_variant = {
>                 PHY_LANE_2,
>                 PHY_LANE_CK,
>         },
> +       .unsupported_odd_h_timings      = true,
>
>         .init_resources         = vc5_hdmi_init_resources,
>         .csc_setup              = vc5_hdmi_csc_setup,
> @@ -1855,6 +1866,7 @@ static const struct vc4_hdmi_variant bcm2711_hdmi1_variant = {
>                 PHY_LANE_CK,
>                 PHY_LANE_2,
>         },
> +       .unsupported_odd_h_timings      = true,
>
>         .init_resources         = vc5_hdmi_init_resources,
>         .csc_setup              = vc5_hdmi_csc_setup,
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
> index 63c6f8bddf1d..6815e93b1a48 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.h
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
> @@ -62,6 +62,9 @@ struct vc4_hdmi_variant {
>          */
>         enum vc4_hdmi_phy_channel phy_lane_mapping[4];
>
> +       /* The BCM2711 cannot deal with odd horizontal pixel timings */
> +       bool unsupported_odd_h_timings;
> +
>         /* Callback to get the resources (memory region, interrupts,
>          * clocks, etc) for that variant.
>          */
> --
> 2.26.2
>
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

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

[Dave Stevenson]

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
>
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH v2 2/2] drm/vc4: hdmi: Block odd horizontal timings

[Maxime Ripard]

[-- Attachment #1.1: Type: text/plain, Size: 550 bytes --]

On Thu, Nov 19, 2020 at 11:14:50AM +0000, Dave Stevenson wrote:
> Hi Maxime
> 
> Thanks for the rewording :-)
> 
> On Thu, 29 Oct 2020 at 12:25, Maxime Ripard <maxime@cerno.tech> wrote:
> >
> > The FIFO between the pixelvalve and the HDMI controller runs at 2 pixels
> > per clock cycle, and cannot deal with odd timings.
> >
> > Let's reject any mode with such timings.
> >
> > Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> 
> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

Applied both patches, thanks!
Maxime

[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel