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

[Sharma, Shashank]

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>

- 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