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authorShashank Sharma <shashank.sharma@intel.com>2017-07-14 16:03:46 +0530
committerVille Syrjälä <ville.syrjala@linux.intel.com>2017-07-14 21:23:54 +0300
commit832d4f2f417d1786769c7a91a0a6363ea58cfc10 (patch)
treef6fa8a9581b4ebea9ac5e0bd2fc6dd16a3828881 /drivers/gpu/drm/drm_edid.c
parentd85231530b0719e23a62d92ee35712da966e281a (diff)
downloadlinux-832d4f2f417d1786769c7a91a0a6363ea58cfc10.tar.bz2
drm/edid: parse YCBCR420 videomodes from EDID
HDMI 2.0 spec adds support for YCBCR420 sub-sampled output. CEA-861-F adds two new blocks in EDID's CEA extension blocks, to provide information about sink's YCBCR420 output capabilities. These blocks are: - YCBCR420vdb(YCBCR 420 video data block): This block contains VICs of video modes, which can be sopported only in YCBCR420 output mode (Not in RGB/YCBCR444/422. Its like a normal SVD block, valid for YCBCR420 modes only. - YCBCR420cmdb(YCBCR 420 capability map data block): This block gives information about video modes which can support YCBCR420 output mode also (along with RGB,YCBCR444/422 etc) This block contains a bitmap index of normal svd videomodes, which can support YCBCR420 output too. So if bit 0 from first vcb byte is set, first video mode in the svd list can support YCBCR420 output too. Bit 1 means second video mode from svd list can support YCBCR420 output too, and so on. This patch adds two bitmaps in display's hdmi_info structure, one each for VCB and VDB modes. If the source is HDMI 2.0 capable, this patch adds: - VDB modes (YCBCR 420 only modes) in connector's mode list, also makes an entry in the vdb_bitmap per vic. - VCB modes (YCBCR 420 also modes) only entry in the vcb_bitmap. Cc: Ville Syrjala <ville.syrjala@linux.intel.com> Cc: Jose Abreu <joabreu@synopsys.com> Cc: Emil Velikov <emil.l.velikov@gmail.com> V2: Addressed Review comments from Emil: - Use 1ULL<<i instead of 1<<i to make sure the output is 64bit. - Use the suggested method for updating dbmap. - Add documentation for YCBCR420_vcb_map to fix kbuild warning. Review comments from Ville: - Do not expose the YCBCR420 flags in uabi layer, keep it internal. - Save a map of YCBCR420 modes for future reference. - Check db length before trying to parse extended tag. - Add a warning if there are > 64 modes in capability map block. - Use y420cmdb in function names and macros while dealing with vcb to be aligned with spec. - Move the display information parsing block ahead of mode parsing blocks. V3: Addressed design/review comments from Ville - Do not add flags in video modes, else we have to expose them to user - There should not be a UABI change, and kernel should detect the choice of the output based on type of mode, and the bitmaps. - Use standard bitops from kernel bitmap header, instead of calculating bit positions manually. V4: Addressed review comments from Ville: - s/ycbcr_420_vdb/y420vdb - s/ycbcr_420_vcb/y420cmdb - Be less verbose on description of do_y420vdb_modes - Move newmode variable in the loop scope. - Use svd_to_vic() to get a VIC, instead of 0x7f - Remove bitmap description for CMDB modes & VDB modes - Dont add connector->ycbcr_420_allowed check for cmdb modes - Remove 'len' variable, in is_y420cmdb function, which is used only once - Add length check in is_y420vdb function - Remove unnecessary if (!db) check in function parse_y420cmdb_bitmap - Do not add print about YCBCR 420 modes - Fix indentation in few places - Move ycbcr420_dc_modes in next patch, where its used - Add a separate patch for movement of drm_add_display_info() V5: Addressed review comments from Ville: - Add the patch which cleans up the current EXTENDED_TAG usage - Make y420_cmdb_map u64 - Do not block ycbcr420 modes while parsing the EDID, rather add a separate helper function to prune ycbcr420-only modes from connector's probed modes. V6: Rebase V7: Move this patch after the 420_only validation patch (Ville) V8: Addressed review comments from Ville - use cea_vic_valid check before adding cmdb/vdb modes - add check for i < 64 while adding cmdb modes - use 1ULL while checking bitmap Signed-off-by: Shashank Sharma <shashank.sharma@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1500028426-14883-1-git-send-email-shashank.sharma@intel.com [vsyrjala: Fix checkpatch complaints and indentation] Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Diffstat (limited to 'drivers/gpu/drm/drm_edid.c')
-rw-r--r--drivers/gpu/drm/drm_edid.c152
1 files changed, 150 insertions, 2 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 9a3937527058..31881a71118d 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -2783,6 +2783,8 @@ add_detailed_modes(struct drm_connector *connector, struct edid *edid,
#define SPEAKER_BLOCK 0x04
#define USE_EXTENDED_TAG 0x07
#define EXT_VIDEO_CAPABILITY_BLOCK 0x00
+#define EXT_VIDEO_DATA_BLOCK_420 0x0E
+#define EXT_VIDEO_CAP_BLOCK_Y420CMDB 0x0F
#define EDID_BASIC_AUDIO (1 << 6)
#define EDID_CEA_YCRCB444 (1 << 5)
#define EDID_CEA_YCRCB422 (1 << 4)
@@ -3153,15 +3155,85 @@ drm_display_mode_from_vic_index(struct drm_connector *connector,
return newmode;
}
+/*
+ * do_y420vdb_modes - Parse YCBCR 420 only modes
+ * @connector: connector corresponding to the HDMI sink
+ * @svds: start of the data block of CEA YCBCR 420 VDB
+ * @len: length of the CEA YCBCR 420 VDB
+ *
+ * Parse the CEA-861-F YCBCR 420 Video Data Block (Y420VDB)
+ * which contains modes which can be supported in YCBCR 420
+ * output format only.
+ */
+static int do_y420vdb_modes(struct drm_connector *connector,
+ const u8 *svds, u8 svds_len)
+{
+ int modes = 0, i;
+ struct drm_device *dev = connector->dev;
+ struct drm_display_info *info = &connector->display_info;
+ struct drm_hdmi_info *hdmi = &info->hdmi;
+
+ for (i = 0; i < svds_len; i++) {
+ u8 vic = svd_to_vic(svds[i]);
+ struct drm_display_mode *newmode;
+
+ if (!drm_valid_cea_vic(vic))
+ continue;
+
+ newmode = drm_mode_duplicate(dev, &edid_cea_modes[vic]);
+ if (!newmode)
+ break;
+ bitmap_set(hdmi->y420_vdb_modes, vic, 1);
+ drm_mode_probed_add(connector, newmode);
+ modes++;
+ }
+
+ if (modes > 0)
+ info->color_formats |= DRM_COLOR_FORMAT_YCRCB420;
+ return modes;
+}
+
+/*
+ * drm_add_cmdb_modes - Add a YCBCR 420 mode into bitmap
+ * @connector: connector corresponding to the HDMI sink
+ * @vic: CEA vic for the video mode to be added in the map
+ *
+ * Makes an entry for a videomode in the YCBCR 420 bitmap
+ */
+static void
+drm_add_cmdb_modes(struct drm_connector *connector, u8 svd)
+{
+ u8 vic = svd_to_vic(svd);
+ struct drm_hdmi_info *hdmi = &connector->display_info.hdmi;
+
+ if (!drm_valid_cea_vic(vic))
+ return;
+
+ bitmap_set(hdmi->y420_cmdb_modes, vic, 1);
+}
+
static int
do_cea_modes(struct drm_connector *connector, const u8 *db, u8 len)
{
int i, modes = 0;
+ struct drm_hdmi_info *hdmi = &connector->display_info.hdmi;
for (i = 0; i < len; i++) {
struct drm_display_mode *mode;
mode = drm_display_mode_from_vic_index(connector, db, len, i);
if (mode) {
+ /*
+ * YCBCR420 capability block contains a bitmap which
+ * gives the index of CEA modes from CEA VDB, which
+ * can support YCBCR 420 sampling output also (apart
+ * from RGB/YCBCR444 etc).
+ * For example, if the bit 0 in bitmap is set,
+ * first mode in VDB can support YCBCR420 output too.
+ * Add YCBCR420 modes only if sink is HDMI 2.0 capable.
+ */
+ if (i < 64 && hdmi->y420_cmdb_map & (1ULL << i))
+ drm_add_cmdb_modes(connector, db[i]);
+
drm_mode_probed_add(connector, mode);
modes++;
}
@@ -3503,9 +3575,77 @@ static bool cea_db_is_hdmi_forum_vsdb(const u8 *db)
return oui == HDMI_FORUM_IEEE_OUI;
}
+static bool cea_db_is_y420cmdb(const u8 *db)
+{
+ if (cea_db_tag(db) != USE_EXTENDED_TAG)
+ return false;
+
+ if (!cea_db_payload_len(db))
+ return false;
+
+ if (cea_db_extended_tag(db) != EXT_VIDEO_CAP_BLOCK_Y420CMDB)
+ return false;
+
+ return true;
+}
+
+static bool cea_db_is_y420vdb(const u8 *db)
+{
+ if (cea_db_tag(db) != USE_EXTENDED_TAG)
+ return false;
+
+ if (!cea_db_payload_len(db))
+ return false;
+
+ if (cea_db_extended_tag(db) != EXT_VIDEO_DATA_BLOCK_420)
+ return false;
+
+ return true;
+}
+
#define for_each_cea_db(cea, i, start, end) \
for ((i) = (start); (i) < (end) && (i) + cea_db_payload_len(&(cea)[(i)]) < (end); (i) += cea_db_payload_len(&(cea)[(i)]) + 1)
+static void drm_parse_y420cmdb_bitmap(struct drm_connector *connector,
+ const u8 *db)
+{
+ struct drm_display_info *info = &connector->display_info;
+ struct drm_hdmi_info *hdmi = &info->hdmi;
+ u8 map_len = cea_db_payload_len(db) - 1;
+ u8 count;
+ u64 map = 0;
+
+ if (map_len == 0) {
+ /* All CEA modes support ycbcr420 sampling also.*/
+ hdmi->y420_cmdb_map = U64_MAX;
+ info->color_formats |= DRM_COLOR_FORMAT_YCRCB420;
+ return;
+ }
+
+ /*
+ * This map indicates which of the existing CEA block modes
+ * from VDB can support YCBCR420 output too. So if bit=0 is
+ * set, first mode from VDB can support YCBCR420 output too.
+ * We will parse and keep this map, before parsing VDB itself
+ * to avoid going through the same block again and again.
+ *
+ * Spec is not clear about max possible size of this block.
+ * Clamping max bitmap block size at 8 bytes. Every byte can
+ * address 8 CEA modes, in this way this map can address
+ * 8*8 = first 64 SVDs.
+ */
+ if (WARN_ON_ONCE(map_len > 8))
+ map_len = 8;
+
+ for (count = 0; count < map_len; count++)
+ map |= (u64)db[2 + count] << (8 * count);
+
+ if (map)
+ info->color_formats |= DRM_COLOR_FORMAT_YCRCB420;
+
+ hdmi->y420_cmdb_map = map;
+}
+
static int
add_cea_modes(struct drm_connector *connector, struct edid *edid)
{
@@ -3528,10 +3668,16 @@ add_cea_modes(struct drm_connector *connector, struct edid *edid)
video = db + 1;
video_len = dbl;
modes += do_cea_modes(connector, video, dbl);
- }
- else if (cea_db_is_hdmi_vsdb(db)) {
+ } else if (cea_db_is_hdmi_vsdb(db)) {
hdmi = db;
hdmi_len = dbl;
+ } else if (cea_db_is_y420vdb(db)) {
+ const u8 *vdb420 = &db[2];
+
+ /* Add 4:2:0(only) modes present in EDID */
+ modes += do_y420vdb_modes(connector,
+ vdb420,
+ dbl - 1);
}
}
}
@@ -4214,6 +4360,8 @@ static void drm_parse_cea_ext(struct drm_connector *connector,
drm_parse_hdmi_vsdb_video(connector, db);
if (cea_db_is_hdmi_forum_vsdb(db))
drm_parse_hdmi_forum_vsdb(connector, db);
+ if (cea_db_is_y420cmdb(db))
+ drm_parse_y420cmdb_bitmap(connector, db);
}
}