linux-kernel - Re: [PATCH] drm: Parse Colorimetry data block from EDID

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Message-ID: <4cadf318-cfc3-92d6-6219-170166db94ce@rock-chips.com>
Date:   Fri, 28 Aug 2020 09:07:13 +0800
From:   crj <algea.cao@...k-chips.com>
To:     Ville Syrjälä <ville.syrjala@...ux.intel.com>
Cc:     mripard@...nel.org, tzimmermann@...e.de,
        linux-kernel@...r.kernel.org, airlied@...ux.ie,
        dri-devel@...ts.freedesktop.org, maarten.lankhorst@...ux.intel.com,
        daniel@...ll.ch, linux-rockchip@...ts.infradead.org
Subject: Re: [PATCH] drm: Parse Colorimetry data block from EDID

Hi Ville Syrjälä,

在 2020/8/27 18:57, Ville Syrjälä 写道:
> On Wed, Aug 26, 2020 at 10:23:28PM +0800, Algea Cao wrote:
>> CEA 861.3 spec adds colorimetry data block for HDMI.
>> Parsing the block to get the colorimetry data from
>> panel.
> And what exactly do you want to do with that data?

We can get colorimetry data block from edid then support

HDMI colorimetry such as BT2020.

>> Signed-off-by: Algea Cao <algea.cao@...k-chips.com>
>> ---
>>
>>   drivers/gpu/drm/drm_edid.c  | 45 +++++++++++++++++++++++++++++++++++++
>>   include/drm/drm_connector.h |  3 +++
>>   include/drm/drm_edid.h      | 14 ++++++++++++
>>   3 files changed, 62 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
>> index 31496b6cfc56..67e607c04492 100644
>> --- a/drivers/gpu/drm/drm_edid.c
>> +++ b/drivers/gpu/drm/drm_edid.c
>> @@ -3223,6 +3223,7 @@ add_detailed_modes(struct drm_connector *connector, struct edid *edid,
>>   #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
>> @@ -4309,6 +4310,48 @@ 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)
>> +{
>> +	if (cea_db_tag(db) != USE_EXTENDED_TAG)
>> +		return false;
>> +
>> +	if (db[1] != COLORIMETRY_DATA_BLOCK)
>> +		return false;
>> +
>> +	if (cea_db_payload_len(db) < 2)
>> +		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;
>> +
>> +	if (db[2] & DRM_EDID_CLRMETRY_xvYCC_601)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_xvYCC_601;
>> +	if (db[2] & DRM_EDID_CLRMETRY_xvYCC_709)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_xvYCC_709;
>> +	if (db[2] & DRM_EDID_CLRMETRY_sYCC_601)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_sYCC_601;
>> +	if (db[2] & DRM_EDID_CLRMETRY_ADBYCC_601)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_ADBYCC_601;
>> +	if (db[2] & DRM_EDID_CLRMETRY_ADB_RGB)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_ADB_RGB;
>> +	if (db[2] & DRM_EDID_CLRMETRY_BT2020_CYCC)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_BT2020_CYCC;
>> +	if (db[2] & DRM_EDID_CLRMETRY_BT2020_YCC)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_BT2020_YCC;
>> +	if (db[2] & DRM_EDID_CLRMETRY_BT2020_RGB)
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_BT2020_RGB;
>> +	/* Byte 4 Bit 7: DCI-P3 */
>> +	if (db[3] & BIT(7))
>> +		info->colorimetry |= DRM_EDID_CLRMETRY_DCI_P3;
>> +
>> +	DRM_DEBUG_KMS("Supported Colorimetry 0x%x\n", info->colorimetry);
>> +}
>> +
>>   static bool cea_db_is_hdmi_hdr_metadata_block(const u8 *db)
>>   {
>>   	if (cea_db_tag(db) != USE_EXTENDED_TAG)
>> @@ -4994,6 +5037,8 @@ 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 af145608b5ed..d599c3b9e881 100644
>> --- a/include/drm/drm_connector.h
>> +++ b/include/drm/drm_connector.h
>> @@ -207,6 +207,9 @@ 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;
>>   };
>>   
>>   /**
>> diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
>> index cfa4f5af49af..98fa78c2f82d 100644
>> --- a/include/drm/drm_edid.h
>> +++ b/include/drm/drm_edid.h
>> @@ -229,6 +229,20 @@ struct detailed_timing {
>>   				    DRM_EDID_YCBCR420_DC_36 | \
>>   				    DRM_EDID_YCBCR420_DC_30)
>>   
>> +/*
>> + * Supported Colorimetry from colorimetry data block
>> + * as per CEA 861-G spec
>> + */
>> +#define DRM_EDID_CLRMETRY_xvYCC_601   (1 << 0)
>> +#define DRM_EDID_CLRMETRY_xvYCC_709   (1 << 1)
>> +#define DRM_EDID_CLRMETRY_sYCC_601    (1 << 2)
>> +#define DRM_EDID_CLRMETRY_ADBYCC_601  (1 << 3)
>> +#define DRM_EDID_CLRMETRY_ADB_RGB     (1 << 4)
>> +#define DRM_EDID_CLRMETRY_BT2020_CYCC (1 << 5)
>> +#define DRM_EDID_CLRMETRY_BT2020_YCC  (1 << 6)
>> +#define DRM_EDID_CLRMETRY_BT2020_RGB  (1 << 7)
>> +#define DRM_EDID_CLRMETRY_DCI_P3      (1 << 15)
>> +
>>   /* ELD Header Block */
>>   #define DRM_ELD_HEADER_BLOCK_SIZE	4
>>   
>> -- 
>> 2.25.1
>>
>>
>>
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@...ts.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel

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