diff options
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 55 |
1 files changed, 54 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index a83d9c73bcc8..883a0c44714c 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1797,6 +1797,7 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, int i; struct drm_fb_helper_surface_size sizes; int gamma_size = 0; + int best_depth = 0; memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size)); sizes.surface_depth = 24; @@ -1804,7 +1805,10 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, sizes.fb_width = (u32)-1; sizes.fb_height = (u32)-1; - /* if driver picks 8 or 16 by default use that for both depth/bpp */ + /* + * If driver picks 8 or 16 by default use that for both depth/bpp + * to begin with + */ if (preferred_bpp != sizes.surface_bpp) sizes.surface_depth = sizes.surface_bpp = preferred_bpp; @@ -1839,6 +1843,55 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, } } + /* + * If we run into a situation where, for example, the primary plane + * supports RGBA5551 (16 bpp, depth 15) but not RGB565 (16 bpp, depth + * 16) we need to scale down the depth of the sizes we request. + */ + for (i = 0; i < fb_helper->crtc_count; i++) { + struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set; + struct drm_crtc *crtc = mode_set->crtc; + struct drm_plane *plane = crtc->primary; + int j; + + DRM_DEBUG("test CRTC %d primary plane\n", i); + + for (j = 0; j < plane->format_count; j++) { + const struct drm_format_info *fmt; + + fmt = drm_format_info(plane->format_types[j]); + + /* + * Do not consider YUV or other complicated formats + * for framebuffers. This means only legacy formats + * are supported (fmt->depth is a legacy field) but + * the framebuffer emulation can only deal with such + * formats, specifically RGB/BGA formats. + */ + if (fmt->depth == 0) + continue; + + /* We found a perfect fit, great */ + if (fmt->depth == sizes.surface_depth) { + best_depth = fmt->depth; + break; + } + + /* Skip depths above what we're looking for */ + if (fmt->depth > sizes.surface_depth) + continue; + + /* Best depth found so far */ + if (fmt->depth > best_depth) + best_depth = fmt->depth; + } + } + if (sizes.surface_depth != best_depth) { + DRM_INFO("requested bpp %d, scaled depth down to %d", + sizes.surface_bpp, best_depth); + sizes.surface_depth = best_depth; + } + crtc_count = 0; for (i = 0; i < fb_helper->crtc_count; i++) { struct drm_display_mode *desired_mode; |