Commit a07e6f56 authored by Ankit Nautiyal's avatar Ankit Nautiyal Committed by Jani Nikula
Browse files

drm/edid: Refactor HFVSDB parsing for DSC1.2 



DSC capabilities are given in bytes 11-13 of VSDB (i.e. bytes 8-10 of
SCDS). Since minimum length of Data block is 7, all bytes greater than 7
must be read only after checking the length of the data block.

This patch adds check for data block length before reading relavant DSC
bytes.

Signed-off-by: default avatarAnkit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: default avatarJani Nikula <jani.nikula@intel.com>
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220916100551.2531750-4-ankit.k.nautiyal@intel.com
parent 5e706c4d

drivers/gpu/drm/drm_edid.c

+49 −44
Original line number Diff line number Diff line
@@ -5755,9 +5755,6 @@ static void drm_parse_ycbcr420_deep_color_info(struct drm_connector *connector, 
static void drm_parse_dsc_info(struct drm_hdmi_dsc_cap *hdmi_dsc,

			       const u8 *hf_scds)

{

	u8 dsc_max_slices;

	u8 dsc_max_frl_rate;



	hdmi_dsc->v_1p2 = hf_scds[11] & DRM_EDID_DSC_1P2;



	if (!hdmi_dsc->v_1p2)
@@ -5776,10 +5773,13 @@ static void drm_parse_dsc_info(struct drm_hdmi_dsc_cap *hdmi_dsc, 
		/* Supports min 8 BPC if DSC 1.2 is supported*/

		hdmi_dsc->bpc_supported = 8;



	if (cea_db_payload_len(hf_scds) >= 12 && hf_scds[12]) {

		u8 dsc_max_slices;

		u8 dsc_max_frl_rate;



		dsc_max_frl_rate = (hf_scds[12] & DRM_EDID_DSC_MAX_FRL_RATE_MASK) >> 4;

		drm_get_max_frl_rate(dsc_max_frl_rate, &hdmi_dsc->max_lanes,

				     &hdmi_dsc->max_frl_rate_per_lane);

	hdmi_dsc->total_chunk_kbytes = hf_scds[13] & DRM_EDID_DSC_TOTAL_CHUNK_KBYTES;



		dsc_max_slices = hf_scds[12] & DRM_EDID_DSC_MAX_SLICES;
@@ -5819,12 +5819,17 @@ static void drm_parse_dsc_info(struct drm_hdmi_dsc_cap *hdmi_dsc, 
		}

	}



	if (cea_db_payload_len(hf_scds) >= 13 && hf_scds[13])

		hdmi_dsc->total_chunk_kbytes = hf_scds[13] & DRM_EDID_DSC_TOTAL_CHUNK_KBYTES;

}



/* Sink Capability Data Structure */

static void drm_parse_hdmi_forum_scds(struct drm_connector *connector,

				      const u8 *hf_scds)

{

	struct drm_display_info *display = &connector->display_info;

	struct drm_hdmi_info *hdmi = &display->hdmi;

	struct drm_hdmi_dsc_cap *hdmi_dsc = &hdmi->dsc_cap;



	display->has_hdmi_infoframe = true;
@@ -5865,17 +5870,17 @@ static void drm_parse_hdmi_forum_scds(struct drm_connector *connector, 


	if (hf_scds[7]) {

		u8 max_frl_rate;

		struct drm_hdmi_dsc_cap *hdmi_dsc = &hdmi->dsc_cap;



		DRM_DEBUG_KMS("hdmi_21 sink detected. parsing edid\n");

		max_frl_rate = (hf_scds[7] & DRM_EDID_MAX_FRL_RATE_MASK) >> 4;

		drm_get_max_frl_rate(max_frl_rate, &hdmi->max_lanes,

				     &hdmi->max_frl_rate_per_lane);



		drm_parse_dsc_info(hdmi_dsc, hf_scds);

	}



	drm_parse_ycbcr420_deep_color_info(connector, hf_scds);



	if (cea_db_payload_len(hf_scds) >= 11 && hf_scds[11])

		drm_parse_dsc_info(hdmi_dsc, hf_scds);

}



static void drm_parse_hdmi_deep_color_info(struct drm_connector *connector,