[v5 03/13] drm: Parse Colorimetry data block from EDID

[Shankar, Uma]

>-----Original Message-----
>From: Sharma, Shashank
>Sent: Friday, March 15, 2019 1:01 PM
>To: Shankar, Uma <uma.shankar at intel.com>; intel-gfx at lists.freedesktop.org; dri-
>devel at lists.freedesktop.org
>Cc: Lankhorst, Maarten <maarten.lankhorst at intel.com>; Syrjala, Ville
><ville.syrjala at intel.com>; emil.l.velikov at gmail.com; brian.starkey at arm.com;
>Liviu.Dudau at arm.com
>Subject: RE: [v5 03/13] drm: Parse Colorimetry data block from EDID
>
>
>
>> -----Original Message-----
>> From: Shankar, Uma
>> Sent: Monday, March 11, 2019 9:28 AM
>> To: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org
>> Cc: Lankhorst, Maarten <maarten.lankhorst at intel.com>; Syrjala, Ville
>> <ville.syrjala at intel.com>; Sharma, Shashank
>> <shashank.sharma at intel.com>; emil.l.velikov at gmail.com;
>> brian.starkey at arm.com; Liviu.Dudau at arm.com; Shankar, Uma
>> <uma.shankar at intel.com>
>> Subject: [v5 03/13] drm: Parse Colorimetry data block from EDID
>>
>> CEA 861.3 spec adds colorimetry data block for HDMI.
>> Parsing the block to get the colorimetry data from panel.
>>
>> v2: Rebase
>>
>> v3: No Change
>>
>> v4: Addressed Shashank's review comments. Updated colorimetry field to
>> 16 bit as
>> DCI-P3 got added in CEA 861-G spec, as pointed out by Shashank.
>>
>> Signed-off-by: Uma Shankar <uma.shankar at intel.com>
>> ---
>>  drivers/gpu/drm/drm_edid.c  | 26 ++++++++++++++++++++++++++
>> include/drm/drm_connector.h |  3 +++
>>  2 files changed, 29 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
>> index
>> c5a81b8..0470845 100644
>> --- a/drivers/gpu/drm/drm_edid.c
>> +++ b/drivers/gpu/drm/drm_edid.c
>> @@ -2834,6 +2834,7 @@ static int drm_cvt_modes(struct drm_connector
>> *connector,
>>  #define VIDEO_BLOCK     0x02
>>  #define VENDOR_BLOCK    0x03
>>  #define SPEAKER_BLOCK	0x04
>> +#define COLORIMETRY_DATA_BLOCK		0x5
>>  #define HDR_STATIC_METADATA_BLOCK	0x6
>>  #define USE_EXTENDED_TAG 0x07
>>  #define EXT_VIDEO_CAPABILITY_BLOCK 0x00 @@ -3823,6 +3824,29 @@ static
>> void fixup_detailed_cea_mode_clock(struct drm_display_mode *mode)
>>  	mode->clock = clock;
>>  }
>>
>> +static bool cea_db_is_hdmi_colorimetry_data_block(const u8 *db) {
>Same comment for the opening brace above ?

Again this looks like  mail client issue.

>> +	if (cea_db_tag(db) != USE_EXTENDED_TAG)
>> +		return false;
>> +
>> +	if (db[1] != COLORIMETRY_DATA_BLOCK)
>Space before '!' ?

Same here.

>> +		return false;
>> +
>> +	return true;
>> +}
>> +
>> +static void
>> +drm_parse_colorimetry_data_block(struct drm_connector *connector,
>> +const
>> +u8 *db) {
>> +	struct drm_hdmi_info *info = &connector->display_info.hdmi;
>> +	uint16_t len;
>> +
>> +	len = cea_db_payload_len_ext(db);
>> +	/* As per CEA 861-G spec */
>> +	info->colorimetry = ((db[3] & (0x1 << 7)) << 1) | db[2]; }
>This means we are setting the 15th bit for DCI-P3 then there is a gap of 7 bits, and
>then there are other bits. Do we want to make DCI-P3 as bit 8 ? Anyways this can be
>differed for a discussion later.

This is at 8th position only.  We are shifting the db[3] which is 8 bit by 1 and keeping the 7th bit (DCI-P3)
at the 8th position (if we count from 0).

Regards,
Uma Shankar

>> +
>> +
>>  static bool cea_db_is_hdmi_hdr_metadata_block(const u8 *db)  {
>>  	if (cea_db_tag(db) != USE_EXTENDED_TAG) @@ -4495,6 +4519,8 @@ static
>> void drm_parse_cea_ext(struct drm_connector *connector,
>>  			drm_parse_vcdb(connector, db);
>>  		if (cea_db_is_hdmi_hdr_metadata_block(db))
>>  			drm_parse_hdr_metadata_block(connector, db);
>> +		if (cea_db_is_hdmi_colorimetry_data_block(db))
>> +			drm_parse_colorimetry_data_block(connector, db);
>>  	}
>>  }
>>
>> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
>> index 29388bd..94f926e 100644
>> --- a/include/drm/drm_connector.h
>> +++ b/include/drm/drm_connector.h
>> @@ -206,6 +206,9 @@ struct drm_hdmi_info {
>>
>>  	/** @y420_dc_modes: bitmap of deep color support index */
>>  	u8 y420_dc_modes;
>> +
>> +	/* @colorimetry: bitmap of supported colorimetry modes */
>> +	u16 colorimetry;
>- Shashank
>>  };
>>
>>  /**
>> --
>> 1.9.1