diff mbox series

drm/nouveau/disp: Support more modes by checking with lower bpc

Message ID 20230330223938.4025569-1-kherbst@redhat.com (mailing list archive)
State New, archived
Headers show
Series drm/nouveau/disp: Support more modes by checking with lower bpc | expand

Commit Message

Karol Herbst March 30, 2023, 10:39 p.m. UTC
This allows us to advertise more modes especially on HDR displays.

Fixes using 4K@60 modes on my TV and main display both using a HDMI to DP
adapter. Also fixes similiar issues for users running into this.

Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: Karol Herbst <kherbst@redhat.com>
---
 drivers/gpu/drm/nouveau/dispnv50/disp.c | 32 +++++++++++++++++++++++++
 drivers/gpu/drm/nouveau/nouveau_dp.c    |  8 ++++---
 2 files changed, 37 insertions(+), 3 deletions(-)

Comments

Lyude Paul March 31, 2023, 8:51 p.m. UTC | #1
Reviewed-by: Lyude Paul <lyude@redhat.com>

On Fri, 2023-03-31 at 00:39 +0200, Karol Herbst wrote:
> This allows us to advertise more modes especially on HDR displays.
> 
> Fixes using 4K@60 modes on my TV and main display both using a HDMI to DP
> adapter. Also fixes similiar issues for users running into this.
> 
> Cc: stable@vger.kernel.org # 5.10+
> Signed-off-by: Karol Herbst <kherbst@redhat.com>
> ---
>  drivers/gpu/drm/nouveau/dispnv50/disp.c | 32 +++++++++++++++++++++++++
>  drivers/gpu/drm/nouveau/nouveau_dp.c    |  8 ++++---
>  2 files changed, 37 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index ed9d374147b8d..f28e47c161dd9 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -363,6 +363,35 @@ nv50_outp_atomic_check_view(struct drm_encoder *encoder,
>  	return 0;
>  }
>  
> +static void
> +nv50_outp_atomic_fix_depth(struct drm_encoder *encoder, struct drm_crtc_state *crtc_state)
> +{
> +	struct nv50_head_atom *asyh = nv50_head_atom(crtc_state);
> +	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
> +	struct drm_display_mode *mode = &asyh->state.adjusted_mode;
> +	unsigned int max_rate, mode_rate;
> +
> +	switch (nv_encoder->dcb->type) {
> +	case DCB_OUTPUT_DP:
> +		max_rate = nv_encoder->dp.link_nr * nv_encoder->dp.link_bw;
> +
> +                /* we don't support more than 10 anyway */
> +		asyh->or.bpc = max_t(u8, asyh->or.bpc, 10);
> +
> +		/* reduce the bpc until it works out */
> +		while (asyh->or.bpc > 6) {
> +			mode_rate = DIV_ROUND_UP(mode->clock * asyh->or.bpc * 3, 8);
> +			if (mode_rate <= max_rate)
> +				break;
> +
> +			asyh->or.bpc -= 2;
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
>  static int
>  nv50_outp_atomic_check(struct drm_encoder *encoder,
>  		       struct drm_crtc_state *crtc_state,
> @@ -381,6 +410,9 @@ nv50_outp_atomic_check(struct drm_encoder *encoder,
>  	if (crtc_state->mode_changed || crtc_state->connectors_changed)
>  		asyh->or.bpc = connector->display_info.bpc;
>  
> +	/* We might have to reduce the bpc */
> +	nv50_outp_atomic_fix_depth(encoder, crtc_state);
> +
>  	return 0;
>  }
>  
> diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c
> index e00876f92aeea..d49b4875fc3c9 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_dp.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c
> @@ -263,8 +263,6 @@ nouveau_dp_irq(struct work_struct *work)
>  }
>  
>  /* TODO:
> - * - Use the minimum possible BPC here, once we add support for the max bpc
> - *   property.
>   * - Validate against the DP caps advertised by the GPU (we don't check these
>   *   yet)
>   */
> @@ -276,7 +274,11 @@ nv50_dp_mode_valid(struct drm_connector *connector,
>  {
>  	const unsigned int min_clock = 25000;
>  	unsigned int max_rate, mode_rate, ds_max_dotclock, clock = mode->clock;
> -	const u8 bpp = connector->display_info.bpc * 3;
> +	/* Check with the minmum bpc always, so we can advertise better modes.
> +	 * In particlar not doing this causes modes to be dropped on HDR
> +	 * displays as we might check with a bpc of 16 even.
> +	 */
> +	const u8 bpp = 6 * 3;
>  
>  	if (mode->flags & DRM_MODE_FLAG_INTERLACE && !outp->caps.dp_interlace)
>  		return MODE_NO_INTERLACE;
Karol Herbst April 1, 2023, 12:19 a.m. UTC | #2
On Fri, Mar 31, 2023 at 12:39 AM Karol Herbst <kherbst@redhat.com> wrote:
>
> This allows us to advertise more modes especially on HDR displays.
>
> Fixes using 4K@60 modes on my TV and main display both using a HDMI to DP
> adapter. Also fixes similiar issues for users running into this.
>
> Cc: stable@vger.kernel.org # 5.10+
> Signed-off-by: Karol Herbst <kherbst@redhat.com>
> ---
>  drivers/gpu/drm/nouveau/dispnv50/disp.c | 32 +++++++++++++++++++++++++
>  drivers/gpu/drm/nouveau/nouveau_dp.c    |  8 ++++---
>  2 files changed, 37 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index ed9d374147b8d..f28e47c161dd9 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -363,6 +363,35 @@ nv50_outp_atomic_check_view(struct drm_encoder *encoder,
>         return 0;
>  }
>
> +static void
> +nv50_outp_atomic_fix_depth(struct drm_encoder *encoder, struct drm_crtc_state *crtc_state)
> +{
> +       struct nv50_head_atom *asyh = nv50_head_atom(crtc_state);
> +       struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
> +       struct drm_display_mode *mode = &asyh->state.adjusted_mode;
> +       unsigned int max_rate, mode_rate;
> +
> +       switch (nv_encoder->dcb->type) {
> +       case DCB_OUTPUT_DP:
> +               max_rate = nv_encoder->dp.link_nr * nv_encoder->dp.link_bw;
> +
> +                /* we don't support more than 10 anyway */
> +               asyh->or.bpc = max_t(u8, asyh->or.bpc, 10);

luckily I didn't push yet, but this has to be `min_t` :)

> +
> +               /* reduce the bpc until it works out */
> +               while (asyh->or.bpc > 6) {
> +                       mode_rate = DIV_ROUND_UP(mode->clock * asyh->or.bpc * 3, 8);
> +                       if (mode_rate <= max_rate)
> +                               break;
> +
> +                       asyh->or.bpc -= 2;
> +               }
> +               break;
> +       default:
> +               break;
> +       }
> +}
> +
>  static int
>  nv50_outp_atomic_check(struct drm_encoder *encoder,
>                        struct drm_crtc_state *crtc_state,
> @@ -381,6 +410,9 @@ nv50_outp_atomic_check(struct drm_encoder *encoder,
>         if (crtc_state->mode_changed || crtc_state->connectors_changed)
>                 asyh->or.bpc = connector->display_info.bpc;
>
> +       /* We might have to reduce the bpc */
> +       nv50_outp_atomic_fix_depth(encoder, crtc_state);
> +
>         return 0;
>  }
>
> diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c
> index e00876f92aeea..d49b4875fc3c9 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_dp.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c
> @@ -263,8 +263,6 @@ nouveau_dp_irq(struct work_struct *work)
>  }
>
>  /* TODO:
> - * - Use the minimum possible BPC here, once we add support for the max bpc
> - *   property.
>   * - Validate against the DP caps advertised by the GPU (we don't check these
>   *   yet)
>   */
> @@ -276,7 +274,11 @@ nv50_dp_mode_valid(struct drm_connector *connector,
>  {
>         const unsigned int min_clock = 25000;
>         unsigned int max_rate, mode_rate, ds_max_dotclock, clock = mode->clock;
> -       const u8 bpp = connector->display_info.bpc * 3;
> +       /* Check with the minmum bpc always, so we can advertise better modes.
> +        * In particlar not doing this causes modes to be dropped on HDR
> +        * displays as we might check with a bpc of 16 even.
> +        */
> +       const u8 bpp = 6 * 3;
>
>         if (mode->flags & DRM_MODE_FLAG_INTERLACE && !outp->caps.dp_interlace)
>                 return MODE_NO_INTERLACE;
> --
> 2.39.2
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index ed9d374147b8d..f28e47c161dd9 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -363,6 +363,35 @@  nv50_outp_atomic_check_view(struct drm_encoder *encoder,
 	return 0;
 }
 
+static void
+nv50_outp_atomic_fix_depth(struct drm_encoder *encoder, struct drm_crtc_state *crtc_state)
+{
+	struct nv50_head_atom *asyh = nv50_head_atom(crtc_state);
+	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
+	struct drm_display_mode *mode = &asyh->state.adjusted_mode;
+	unsigned int max_rate, mode_rate;
+
+	switch (nv_encoder->dcb->type) {
+	case DCB_OUTPUT_DP:
+		max_rate = nv_encoder->dp.link_nr * nv_encoder->dp.link_bw;
+
+                /* we don't support more than 10 anyway */
+		asyh->or.bpc = max_t(u8, asyh->or.bpc, 10);
+
+		/* reduce the bpc until it works out */
+		while (asyh->or.bpc > 6) {
+			mode_rate = DIV_ROUND_UP(mode->clock * asyh->or.bpc * 3, 8);
+			if (mode_rate <= max_rate)
+				break;
+
+			asyh->or.bpc -= 2;
+		}
+		break;
+	default:
+		break;
+	}
+}
+
 static int
 nv50_outp_atomic_check(struct drm_encoder *encoder,
 		       struct drm_crtc_state *crtc_state,
@@ -381,6 +410,9 @@  nv50_outp_atomic_check(struct drm_encoder *encoder,
 	if (crtc_state->mode_changed || crtc_state->connectors_changed)
 		asyh->or.bpc = connector->display_info.bpc;
 
+	/* We might have to reduce the bpc */
+	nv50_outp_atomic_fix_depth(encoder, crtc_state);
+
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c
index e00876f92aeea..d49b4875fc3c9 100644
--- a/drivers/gpu/drm/nouveau/nouveau_dp.c
+++ b/drivers/gpu/drm/nouveau/nouveau_dp.c
@@ -263,8 +263,6 @@  nouveau_dp_irq(struct work_struct *work)
 }
 
 /* TODO:
- * - Use the minimum possible BPC here, once we add support for the max bpc
- *   property.
  * - Validate against the DP caps advertised by the GPU (we don't check these
  *   yet)
  */
@@ -276,7 +274,11 @@  nv50_dp_mode_valid(struct drm_connector *connector,
 {
 	const unsigned int min_clock = 25000;
 	unsigned int max_rate, mode_rate, ds_max_dotclock, clock = mode->clock;
-	const u8 bpp = connector->display_info.bpc * 3;
+	/* Check with the minmum bpc always, so we can advertise better modes.
+	 * In particlar not doing this causes modes to be dropped on HDR
+	 * displays as we might check with a bpc of 16 even.
+	 */
+	const u8 bpp = 6 * 3;
 
 	if (mode->flags & DRM_MODE_FLAG_INTERLACE && !outp->caps.dp_interlace)
 		return MODE_NO_INTERLACE;