Commit 832d4f2f authored by Shashank Sharma's avatar Shashank Sharma Committed by Ville Syrjälä

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: default avatarShashank 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: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
parent d8523153
......@@ -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);
}
}
......
......@@ -143,6 +143,17 @@ struct drm_hdmi_info {
* upto 128 VICs;
*/
unsigned long y420_vdb_modes[BITS_TO_LONGS(128)];
/**
* @y420_cmdb_modes: bitmap of modes which can support ycbcr420
* output also, along with normal HDMI outputs. There are total 107
* VICs defined by CEA-861-F spec, so the size is 128 bits to map upto
* 128 VICs;
*/
unsigned long y420_cmdb_modes[BITS_TO_LONGS(128)];
/** @y420_cmdb_map: bitmap of SVD index, to extraxt vcb modes */
u64 y420_cmdb_map;
};
/**
......@@ -206,6 +217,7 @@ struct drm_display_info {
#define DRM_COLOR_FORMAT_RGB444 (1<<0)
#define DRM_COLOR_FORMAT_YCRCB444 (1<<1)
#define DRM_COLOR_FORMAT_YCRCB422 (1<<2)
#define DRM_COLOR_FORMAT_YCRCB420 (1<<3)
/**
* @color_formats: HDMI Color formats, selects between RGB and YCrCb
......
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