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

Shankar, Uma uma.shankar at intel.com
Wed Mar 20 08:58:31 UTC 2019


>On 3/20/2019 12:47 PM, Shankar, Uma wrote:
>>
>>> -----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
>
>My bad,  its 8th bit only.
>
>If those above alignment problems are checked already, feel free to use
>
>Reviewed-by: Shashank Sharma <shashank.sharma at intel.com>

No Issues, Thanks Shashank.

Regards,
Uma Shankar

>- Shashank
>
>>>> +
>>>> +
>>>>   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


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