From: Mario Kleiner mario.kleiner.de@gmail.com
Check the HDMI cea block for deep color mode bits. If available, assign the highest supported bpc for a hdmi display, corresponding to the given deep color modes.
Signed-off-by: Mario Kleiner mario.kleiner.de@gmail.com Signed-off-by: Alex Deucher alexander.deucher@amd.com --- drivers/gpu/drm/drm_edid.c | 110 ++++++++++++++++++++++++++++++++++++++++++++- include/drm/drm_edid.h | 5 +++ 2 files changed, 113 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index d74239f..3989c18 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -3423,16 +3423,116 @@ bool drm_rgb_quant_range_selectable(struct edid *edid) EXPORT_SYMBOL(drm_rgb_quant_range_selectable);
/** + * drm_assign_hdmi_deep_color_info - detect whether monitor supports + * hdmi deep color modes and update drm_display_info if so. + * + * @edid: monitor EDID information + * @info: Updated with maximum supported deep color bpc and color format + * if deep color supported. + * + * Parse the CEA extension according to CEA-861-B. + * Return true if HDMI deep color supported, false if not or unknown. + */ +static bool drm_assign_hdmi_deep_color_info(struct edid *edid, + struct drm_display_info *info, + struct drm_connector *connector) +{ + u8 *edid_ext, *hdmi; + int i; + int start_offset, end_offset; + unsigned int dc_bpc = 0; + + edid_ext = drm_find_cea_extension(edid); + if (!edid_ext) + return false; + + if (cea_db_offsets(edid_ext, &start_offset, &end_offset)) + return false; + + /* + * Because HDMI identifier is in Vendor Specific Block, + * search it from all data blocks of CEA extension. + */ + for_each_cea_db(edid_ext, i, start_offset, end_offset) { + if (cea_db_is_hdmi_vsdb(&edid_ext[i])) { + /* HDMI supports at least 8 bpc */ + info->bpc = 8; + + hdmi = &edid_ext[i]; + if (cea_db_payload_len(hdmi) < 6) + return false; + + if (hdmi[6] & DRM_EDID_HDMI_DC_30) { + dc_bpc = 10; + DRM_DEBUG("%s: HDMI sink does deep color 30.\n", + drm_get_connector_name(connector)); + } + + if (hdmi[6] & DRM_EDID_HDMI_DC_36) { + dc_bpc = 12; + DRM_DEBUG("%s: HDMI sink does deep color 36.\n", + drm_get_connector_name(connector)); + } + + if (hdmi[6] & DRM_EDID_HDMI_DC_48) { + dc_bpc = 16; + DRM_DEBUG("%s: HDMI sink does deep color 48.\n", + drm_get_connector_name(connector)); + } + + if (dc_bpc > 0) { + DRM_DEBUG("%s: Assigning HDMI sink color depth as %d bpc.\n", + drm_get_connector_name(connector), dc_bpc); + info->bpc = dc_bpc; + + /* + * Deep color support mandates RGB444 support for all video + * modes and forbids YCRCB422 support for all video modes per + * HDMI 1.3 spec. + */ + info->color_formats = DRM_COLOR_FORMAT_RGB444; + + /* YCRCB444 is optional according to spec. */ + if (hdmi[6] & DRM_EDID_HDMI_DC_Y444) { + info->color_formats |= DRM_COLOR_FORMAT_YCRCB444; + DRM_DEBUG("%s: HDMI sink does YCRCB444 in deep color.\n", + drm_get_connector_name(connector)); + } + + /* + * Spec says that if any deep color mode is supported at all, + * then deep color 36 bit must be supported. + */ + if (!(hdmi[6] & DRM_EDID_HDMI_DC_36)) { + DRM_DEBUG("%s: HDMI sink should do DC_36, but does not!\n", + drm_get_connector_name(connector)); + } + + return true; + } + else { + DRM_DEBUG("%s: No deep color support on this HDMI sink.\n", + drm_get_connector_name(connector)); + } + } + } + + return false; +} + +/** * drm_add_display_info - pull display info out if present * @edid: EDID data * @info: display info (attached to connector) + * @connector: connector whose edid is used to build display info * * Grab any available display info and stuff it into the drm_display_info * structure that's part of the connector. Useful for tracking bpp and * color spaces. */ static void drm_add_display_info(struct edid *edid, - struct drm_display_info *info) + struct drm_display_info *info, + struct drm_connector *connector) { u8 *edid_ext;
@@ -3462,6 +3562,9 @@ static void drm_add_display_info(struct edid *edid, info->color_formats |= DRM_COLOR_FORMAT_YCRCB422; }
+ /* HDMI deep color modes supported? Assign to info, if so */ + drm_assign_hdmi_deep_color_info(edid, info, connector); + /* Only defined for 1.4 with digital displays */ if (edid->revision < 4) return; @@ -3491,6 +3594,9 @@ static void drm_add_display_info(struct edid *edid, break; }
+ DRM_DEBUG("%s: Assigning EDID-1.4 digital sink color depth as %d bpc.\n", + drm_get_connector_name(connector), info->bpc); + info->color_formats |= DRM_COLOR_FORMAT_RGB444; if (edid->features & DRM_EDID_FEATURE_RGB_YCRCB444) info->color_formats |= DRM_COLOR_FORMAT_YCRCB444; @@ -3549,7 +3655,7 @@ int drm_add_edid_modes(struct drm_connector *connector, struct edid *edid) if (quirks & (EDID_QUIRK_PREFER_LARGE_60 | EDID_QUIRK_PREFER_LARGE_75)) edid_fixup_preferred(connector, quirks);
- drm_add_display_info(edid, &connector->display_info); + drm_add_display_info(edid, &connector->display_info, connector);
if (quirks & EDID_QUIRK_FORCE_8BPC) connector->display_info.bpc = 8; diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index a1441c5..b96031d 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -202,6 +202,11 @@ struct detailed_timing { #define DRM_EDID_FEATURE_PM_SUSPEND (1 << 6) #define DRM_EDID_FEATURE_PM_STANDBY (1 << 7)
+#define DRM_EDID_HDMI_DC_48 (1 << 6) +#define DRM_EDID_HDMI_DC_36 (1 << 5) +#define DRM_EDID_HDMI_DC_30 (1 << 4) +#define DRM_EDID_HDMI_DC_Y444 (1 << 3) + struct edid { u8 header[8]; /* Vendor & product info */