Re: [PATCH v2 1/3] gpu/drm: ingenic: Add trick to support 16bpp on 24-bit panels

Hi,

Any feedback for this patchset?

Thanks, -Paul

Le mer. 26 févr. 2020 à 1:30, Paul Cercueil paul@crapouillou.net a écrit :

If the panel interface is 24-bit but our primary plane is 16bpp, configure as if the panel was 18-bit. This tricks permits the display of 16bpp data on a 24-bit panel by wiring each color component to the MSBs of the 24-bit interface.

v2: Check bytes-per-pixel count instead of fourcc format

Signed-off-by: Paul Cercueil paul@crapouillou.net

drivers/gpu/drm/ingenic/ingenic-drm.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/ingenic/ingenic-drm.c b/drivers/gpu/drm/ingenic/ingenic-drm.c index 6d47ef7b148c..5493a80d7d2f 100644 --- a/drivers/gpu/drm/ingenic/ingenic-drm.c +++ b/drivers/gpu/drm/ingenic/ingenic-drm.c @@ -400,6 +400,8 @@ static void ingenic_drm_encoder_atomic_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode = &crtc_state->adjusted_mode; struct drm_connector *conn = conn_state->connector; struct drm_display_info *info = &conn->display_info;

• struct drm_plane_state *plane_state =

crtc_state->crtc->primary->state;

• const struct drm_format_info *finfo = NULL; unsigned int cfg;

  priv->panel_is_sharp = info->bus_flags & DRM_BUS_FLAG_SHARP_SIGNALS;

@@ -435,7 +437,21 @@ static void ingenic_drm_encoder_atomic_mode_set(struct drm_encoder *encoder, cfg |= JZ_LCD_CFG_MODE_GENERIC_18BIT; break; case MEDIA_BUS_FMT_RGB888_1X24:

• 		cfg |= JZ_LCD_CFG_MODE_GENERIC_24BIT;
  

• 		if (plane_state && plane_state->fb)
  

• 			finfo = plane_state->fb->format;
  

• 		/*
  

• 		 * If the panel interface is 24-bit but our
  

• 		 * primary plane is 16bpp, configure as if the
  

• 		 * panel was 18-bit. This tricks permits the
  

• 		 * display of 16bpp data on a 24-bit panel by
  

• 		 * wiring each color component to the MSBs of
  

• 		 * the 24-bit interface.
  

• 		 */
  

• 		if (finfo && finfo->cpp[0] < 3)
  

• 			cfg |= JZ_LCD_CFG_MODE_GENERIC_18BIT;
  

• 		else
  

• 			cfg |= JZ_LCD_CFG_MODE_GENERIC_24BIT;
  	break;
  case MEDIA_BUS_FMT_RGB888_3X8:
  	cfg |= JZ_LCD_CFG_MODE_8BIT_SERIAL;
  

-- 2.25.0