>-----Original Message----- >From: Ville Syrjälä [mailto:ville.syrjala@xxxxxxxxxxxxxxx] >Sent: Friday, February 8, 2019 8:08 PM >To: Sharma, Shashank <shashank.sharma@xxxxxxxxx> >Cc: Shankar, Uma <uma.shankar@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; >Syrjala, Ville <ville.syrjala@xxxxxxxxx>; dri-devel@xxxxxxxxxxxxxxxxxxxxx; Lankhorst, >Maarten <maarten.lankhorst@xxxxxxxxx> >Subject: Re: [v11 1/4] drm: Add HDMI colorspace property > >On Fri, Feb 08, 2019 at 07:36:24PM +0530, Sharma, Shashank wrote: >> Regards >> >> Shashank >> >> On 2/8/2019 7:00 PM, Ville Syrjälä wrote: >> > On Fri, Feb 08, 2019 at 06:36:39PM +0530, Sharma, Shashank wrote: >> >> Regards >> >> >> >> Shashank >> >> >> >> On 2/8/2019 6:22 PM, Ville Syrjälä wrote: >> >>> On Fri, Feb 08, 2019 at 12:36:25PM +0000, Sharma, Shashank wrote: >> >>>> Regards >> >>>> Shashank >> >>>> >> >>>>> -----Original Message----- >> >>>>> From: Intel-gfx [mailto:intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx] >> >>>>> On Behalf Of Shankar, Uma >> >>>>> Sent: Friday, February 8, 2019 5:45 PM >> >>>>> To: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> >> >>>>> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx; Syrjala, Ville >> >>>>> <ville.syrjala@xxxxxxxxx>; dri- devel@xxxxxxxxxxxxxxxxxxxxx; >> >>>>> Lankhorst, Maarten <maarten.lankhorst@xxxxxxxxx> >> >>>>> Subject: Re: [v11 1/4] drm: Add HDMI colorspace >> >>>>> property >> >>>>> >> >>>>>>>>>> -----Original Message----- >> >>>>>>>>>> From: Ville Syrjälä [mailto:ville.syrjala@xxxxxxxxxxxxxxx] >> >>>>>>>>>> Sent: Tuesday, February 5, 2019 10:02 PM >> >>>>>>>>>> To: Shankar, Uma <uma.shankar@xxxxxxxxx> >> >>>>>>>>>> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx; >> >>>>>>>>>> dri-devel@xxxxxxxxxxxxxxxxxxxxx; Syrjala, Ville >> >>>>>>>>>> <ville.syrjala@xxxxxxxxx>; Lankhorst, Maarten >> >>>>>>>>>> <maarten.lankhorst@xxxxxxxxx> >> >>>>>>>>>> Subject: Re: [v11 1/4] drm: Add HDMI colorspace >> >>>>>>>>>> property >> >>>>>>>>>> >> >>>>>>>>>> On Tue, Feb 05, 2019 at 09:33:34PM +0530, Uma Shankar wrote: >> >>>>>>>>>>> Create a new connector property to program colorspace to sink >devices. >> >>>>>>>>>>> Modern sink devices support more than 1 type of colorspace >> >>>>>>>>>>> like 601, 709, BT2020 etc. This helps to switch based on >> >>>>>>>>>>> content type which is to be displayed. The decision lies >> >>>>>>>>>>> with compositors as to in which scenarios, a particular colorspace will >be picked. >> >>>>>>>>>>> >> >>>>>>>>>>> This will be helpful mostly to switch to higher gamut >> >>>>>>>>>>> colorspaces like >> >>>>>>>>>>> BT2020 when the media content is encoded as BT2020. >> >>>>>>>>>>> Thereby giving a good visual experience to users. >> >>>>>>>>>>> >> >>>>>>>>>>> The expectation from userspace is that it should parse the >> >>>>>>>>>>> EDID and get supported colorspaces. Use this property and >> >>>>>>>>>>> switch to the one supported. Sink supported colorspaces >> >>>>>>>>>>> should be retrieved by userspace from EDID and driver will >> >>>>>>>>>>> not explicitly expose >> >>>>>> them. >> >>>>>>>>>>> Basically the expectation from userspace is: >> >>>>>>>>>>> - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink >> >>>>>>>>>>> colorspace >> >>>>>>>>>>> - Set this new property to let the sink know what it >> >>>>>>>>>>> converted the CRTC output to. >> >>>>>>>>>>> >> >>>>>>>>>>> v2: Addressed Maarten and Ville's review comments. >> >>>>>>>>>>> Enhanced the colorspace enum to incorporate both HDMI and >> >>>>>>>>>>> DP supported >> >>>>>> colorspaces. >> >>>>>>>>>>> Also, added a default option for colorspace. >> >>>>>>>>>>> >> >>>>>>>>>>> v3: Removed Adobe references from enum definitions as per >> >>>>>>>>>>> Ville, Hans Verkuil and Jonas Karlman suggestions. Changed >> >>>>>>>>>>> Default to an unset state where driver will assign the >> >>>>>>>>>>> colorspace is not chosen by user, suggested by Ville and >> >>>>>>>>>>> Maarten. Addressed other misc review comments from Maarten. >> >>>>>>>>>>> Split the changes to have separate colorspace property for DP and >HDMI. >> >>>>>>>>>>> >> >>>>>>>>>>> v4: Addressed Chris and Ville's review comments, and >> >>>>>>>>>>> created a common colorspace property for DP and HDMI, >> >>>>>>>>>>> filtered the list based on the colorspaces supported by the respective >protocol standard. >> >>>>>>>>>>> >> >>>>>>>>>>> v5: Made the property creation helper accept enum list >> >>>>>>>>>>> based on platform capabilties as suggested by Shashank. >> >>>>>>>>>>> Consolidated HDMI and DP property creation in the common helper. >> >>>>>>>>>>> >> >>>>>>>>>>> v6: Addressed Shashank's review comments. >> >>>>>>>>>>> >> >>>>>>>>>>> v7: Added defines instead of enum in uapi as per Brian >> >>>>>>>>>>> Starkey's suggestion in order to go with string matching at userspace. >> >>>>>>>>>>> Updated the commit message to add more details as well kernel docs. >> >>>>>>>>>>> >> >>>>>>>>>>> v8: Addressed Maarten's review comments. >> >>>>>>>>>>> >> >>>>>>>>>>> v9: Removed macro defines from uapi as per Brian Starkey >> >>>>>>>>>>> and Daniel Stone's comments and moved to drm include file. >> >>>>>>>>>>> Moved back to older design with exposing all HDMI >> >>>>>>>>>>> colorspaces to userspace since infoframe capability is >> >>>>>>>>>>> there even on legacy platforms, as per Ville's review comments. >> >>>>>>>>>>> >> >>>>>>>>>>> v10: Fixed sparse warnings, updated the RB from Maarten and Jani's >ack. >> >>>>>>>>>>> >> >>>>>>>>>>> v11: Addressed Ville's review comments. Updated the Macro >> >>>>>>>>>>> naming and added DCI-P3 colorspace as well defined in CEA 861.G >spec. >> >>>>>>>>>>> >> >>>>>>>>>>> Signed-off-by: Uma Shankar <uma.shankar@xxxxxxxxx> >> >>>>>>>>>>> Acked-by: Jani Nikula <jani.nikula@xxxxxxxxx> >> >>>>>>>>>>> Reviewed-by: Shashank Sharma <shashank.sharma@xxxxxxxxx> >> >>>>>>>>>>> Reviewed-by: Maarten Lankhorst >> >>>>>>>>>>> <maarten.lankhorst@xxxxxxxxxxxxxxx> >> >>>>>>>>>>> --- >> >>>>>>>>>>> drivers/gpu/drm/drm_atomic_uapi.c | 4 ++ >> >>>>>>>>>>> drivers/gpu/drm/drm_connector.c | 78 >> >>>>>>>>>> +++++++++++++++++++++++++++++++++++++++ >> >>>>>>>>>>> include/drm/drm_connector.h | 50 >+++++++++++++++++++++++++ >> >>>>>>>>>>> 3 files changed, 132 insertions(+) >> >>>>>>>>>>> >> >>>>>>>>>>> diff --git a/drivers/gpu/drm/drm_atomic_uapi.c >> >>>>>>>>>>> b/drivers/gpu/drm/drm_atomic_uapi.c >> >>>>>>>>>>> index 9a1f41a..9b5d44f 100644 >> >>>>>>>>>>> --- a/drivers/gpu/drm/drm_atomic_uapi.c >> >>>>>>>>>>> +++ b/drivers/gpu/drm/drm_atomic_uapi.c >> >>>>>>>>>>> @@ -746,6 +746,8 @@ static int >> >>>>>>>>>>> drm_atomic_connector_set_property(struct >> >>>>>>>>>> drm_connector *connector, >> >>>>>>>>>>> return -EINVAL; >> >>>>>>>>>>> } >> >>>>>>>>>>> state->content_protection = val; >> >>>>>>>>>>> + } else if (property == connector->colorspace_property) { >> >>>>>>>>>>> + state->colorspace = val; >> >>>>>>>>>>> } else if (property == config->writeback_fb_id_property) { >> >>>>>>>>>>> struct drm_framebuffer *fb = >> >>>>>> drm_framebuffer_lookup(dev, >> >>>>>>>>>> NULL, val); >> >>>>>>>>>>> int ret = >> >>>>>> drm_atomic_set_writeback_fb_for_connector(state, >> >>>>>>>>>> fb); @@ >> >>>>>>>>>>> -814,6 +816,8 @@ static int >> >>>>>>>>>>> drm_atomic_connector_set_property(struct >> >>>>>>>>>> drm_connector *connector, >> >>>>>>>>>>> *val = state->picture_aspect_ratio; >> >>>>>>>>>>> } else if (property == config->content_type_property) { >> >>>>>>>>>>> *val = state->content_type; >> >>>>>>>>>>> + } else if (property == connector->colorspace_property) { >> >>>>>>>>>>> + *val = state->colorspace; >> >>>>>>>>>>> } else if (property == connector->scaling_mode_property) { >> >>>>>>>>>>> *val = state->scaling_mode; >> >>>>>>>>>>> } else if (property == >> >>>>>>>>>>> connector->content_protection_property) >> >>>>>>>>>>> { diff --git a/drivers/gpu/drm/drm_connector.c >> >>>>>>>>>>> b/drivers/gpu/drm/drm_connector.c index 8475396..4309873 >> >>>>>>>>>>> 100644 >> >>>>>>>>>>> --- a/drivers/gpu/drm/drm_connector.c >> >>>>>>>>>>> +++ b/drivers/gpu/drm/drm_connector.c >> >>>>>>>>>>> @@ -826,6 +826,33 @@ int >> >>>>>>>>>>> drm_display_info_set_bus_formats(struct >> >>>>>>>>>>> drm_display_info *info, }; >> >>>>>>>>>>> DRM_ENUM_NAME_FN(drm_get_content_protection_name, >> >>>>>>>>>> drm_cp_enum_list) >> >>>>>>>>>>> +static const struct drm_prop_enum_list hdmi_colorspaces[] = { >> >>>>>>>>>>> + /* For Default case, driver will set the colorspace */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_DEFAULT, "Default" }, >> >>>>>>>>>>> + /* Standard Definition Colorimetry based on CEA 861 */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_SMPTE_170M, >"SMPTE_170M" }, >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_BT709, "BT709" }, >> >>>>>>>>>>> + /* Standard Definition Colorimetry based on IEC 61966-2-4 >*/ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_XVYCC_601, "XVYCC_601" }, >> >>>>>>>>>>> + /* High Definition Colorimetry based on IEC 61966-2-4 */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_XVYCC_709, "XVYCC_709" }, >> >>>>>>>>>>> + /* Colorimetry based on IEC 61966-2-1/Amendment 1 */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_SYCC_601, "SYCC_601" }, >> >>>>>>>>>>> + /* Colorimetry based on IEC 61966-2-5 [33] */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" }, >> >>>>>>>>>>> + /* Colorimetry based on IEC 61966-2-5 */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_OPRGB, "opRGB" }, >> >>>>>>>>>>> + /* Colorimetry based on ITU-R BT.2020 */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" >}, >> >>>>>>>>>>> + /* Colorimetry based on ITU-R BT.2020 */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" >}, >> >>>>>>>>>>> + /* Colorimetry based on ITU-R BT.2020 */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_BT2020_CYCC, >"BT2020_CYCC" }, >> >>>>>>>>>>> + /* Added as part of Additional Colorimetry Extension in >861.G */ >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65, "DCI- >> >>>>>> P3_RGB_D65" }, >> >>>>>>>>>>> + { DRM_MODE_COLORIMETRY_DCI_P3_RGB_THEATER, "DCI- >> >>>>>>>>>> P3_RGB_Theater" }, >> >>>>>>>>>>> +}; >> >>>>>>>>>>> + >> >>>>>>>>>>> /** >> >>>>>>>>>>> * DOC: standard connector properties >> >>>>>>>>>>> * >> >>>>>>>>>>> @@ -1548,6 +1575,57 @@ int >> >>>>>>>>>>> drm_mode_create_aspect_ratio_property(struct drm_device >> >>>>>>>>>>> *dev) >> >>>>>>>>>>> EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property); >> >>>>>>>>>>> >> >>>>>>>>>>> /** >> >>>>>>>>>>> + * DOC: standard connector properties >> >>>>>>>>>>> + * >> >>>>>>>>>>> + * Colorspace: >> >>>>>>>>>>> + * drm_mode_create_colorspace_property - create colorspace >> >>>>>> property >> >>>>>>>>>>> + * This property helps select a suitable colorspace based on the >sink >> >>>>>>>>>>> + * capability. Modern sink devices support wider gamut like >BT2020. >> >>>>>>>>>>> + * This helps switch to BT2020 mode if the BT2020 encoded video >> >>>>>> stream >> >>>>>>>>>>> + * is being played by the user, same for any other colorspace. >Thereby >> >>>>>>>>>>> + * giving a good visual experience to users. >> >>>>>>>>>>> + * >> >>>>>>>>>>> + * The expectation from userspace is that it should parse the EDID >> >>>>>>>>>>> + * and get supported colorspaces. Use this property and switch to >the >> >>>>>>>>>>> + * one supported. Sink supported colorspaces should be retrieved >by >> >>>>>>>>>>> + * userspace from EDID and driver will not explicitly expose them. >> >>>>>>>>>>> + * >> >>>>>>>>>>> + * Basically the expectation from userspace is: >> >>>>>>>>>>> + * - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some >sink >> >>>>>>>>>>> + * colorspace >> >>>>>>>>>>> + * - Set this new property to let the sink know what it >> >>>>>>>>>>> + * converted the CRTC output to. >> >>>>>>>>>>> + * - This property is just to inform sink what colorspace >> >>>>>>>>>>> + * source is trying to drive. >> >>>>>>>>>>> + * >> >>>>>>>>>>> + * Called by a driver the first time it's needed, must be >> >>>>>>>>>>> +attached to desired >> >>>>>>>>>>> + * connectors. >> >>>>>>>>>>> + */ >> >>>>>>>>>>> +int drm_mode_create_colorspace_property(struct >> >>>>>>>>>>> +drm_connector >> >>>>>>>>>>> +*connector) { >> >>>>>>>>>>> + struct drm_device *dev = connector->dev; >> >>>>>>>>>>> + struct drm_property *prop; >> >>>>>>>>>>> + >> >>>>>>>>>>> + if (connector->connector_type == >> >>>>>> DRM_MODE_CONNECTOR_HDMIA || >> >>>>>>>>>>> + connector->connector_type == >> >>>>>> DRM_MODE_CONNECTOR_HDMIB) { >> >>>>>>>>>>> + prop = drm_property_create_enum(dev, >> >>>>>>>>>> DRM_MODE_PROP_ENUM, >> >>>>>>>>>>> + "Colorspace", >> >>>>>>>>>>> + hdmi_colorspaces, >> >>>>>>>>>>> + >> >>>>>>>>>> ARRAY_SIZE(hdmi_colorspaces)); >> >>>>>>>>>>> + if (!prop) >> >>>>>>>>>>> + return -ENOMEM; >> >>>>>>>>>>> + } else { >> >>>>>>>>>>> + DRM_DEBUG_KMS("Colorspace property not >> >>>>>> supported\n"); >> >>>>>>>>>>> + return 0; >> >>>>>>>>>>> + } >> >>>>>>>>>>> + >> >>>>>>>>>>> + connector->colorspace_property = prop; >> >>>>>>>>>>> + >> >>>>>>>>>>> + return 0; >> >>>>>>>>>>> +} >> >>>>>>>>>>> +EXPORT_SYMBOL(drm_mode_create_colorspace_property); >> >>>>>>>>>>> + >> >>>>>>>>>>> +/** >> >>>>>>>>>>> * drm_mode_create_content_type_property - create >> >>>>>>>>>>> content type >> >>>>>> property >> >>>>>>>>>>> * @dev: DRM device >> >>>>>>>>>>> * >> >>>>>>>>>>> diff --git a/include/drm/drm_connector.h >> >>>>>>>>>>> b/include/drm/drm_connector.h index 9941613..58db66e >> >>>>>>>>>>> 100644 >> >>>>>>>>>>> --- a/include/drm/drm_connector.h >> >>>>>>>>>>> +++ b/include/drm/drm_connector.h >> >>>>>>>>>>> @@ -253,6 +253,42 @@ enum drm_panel_orientation { >> >>>>>>>>>>> DRM_MODE_PANEL_ORIENTATION_RIGHT_UP, >> >>>>>>>>>>> }; >> >>>>>>>>>>> >> >>>>>>>>>>> +/* >> >>>>>>>>>>> + * This is a consolidated colorimetry list supported by >> >>>>>>>>>>> +HDMI and >> >>>>>>>>>>> + * DP protocol standard. The respective connectors will >> >>>>>>>>>>> +register >> >>>>>>>>>>> + * a property with the subset of this list (supported by >> >>>>>>>>>>> +that >> >>>>>>>>>>> + * respective protocol). Userspace will set the >> >>>>>>>>>>> +colorspace through >> >>>>>>>>>>> + * a colorspace property which will be created and >> >>>>>>>>>>> +exposed to >> >>>>>>>>>>> + * userspace. >> >>>>>>>>>>> + */ >> >>>>>>>>>>> + >> >>>>>>>>>>> +/* For Default case, driver will set the colorspace */ >> >>>>>>>>>>> +#define DRM_MODE_COLORIMETRY_DEFAULT 0 >> >>>>>>>>>>> +/* CEA 861 Normal Colorimetry options */ >> >>>>>>>>>>> +#define DRM_MODE_COLORIMETRY_NO_DATA 0 >> >>>>>>>>>>> +#define DRM_MODE_COLORIMETRY_SMPTE_170M >> >>>>>>>> 1 >> >>>>>>>>>>> +#define DRM_MODE_COLORIMETRY_BT709 2 >> >>>>>>>>>> Still missing the YCbCr information in these two. >> >>>>>>>>> As per CTA 861.G spec, we have these as only SMPTE_170M and >> >>>>>>>>> ITU-R BT709, with no specific mention of RGB or YCbCr. >> >>>>>>>>> Hence, kept it as per spec. We seem to have a common field for both as >per CTA spec. >> >>>>>>>>> Correct me if my understanding is wrong. >> >>>>>>>> Check >> >>>>>>>> "Table 14 Picture Colorimetry Indicated by the RGB or YC B C >> >>>>>>>> R (Y), Colorimetry >> >>>>>>>> (C) and Extended Colorimetry (EC) Field Settings" >> >>>>>>> These Y2 Y1 Y0 values should be programmed separately and not >> >>>>>>> through the colorspace as they are data formats isn't it. I >> >>>>>>> feel this should get controlled separately independent of >> >>>>>>> colorimetry, or should we add all the YCbCr and RGB versions >> >>>>>>> and program them as part of this property itself >> >>>>>> ? >> >>>>>> >> >>>>>> I don't think we can separate them. The values of the >> >>>>>> colorimetry bits doesn't mean anything without the Y bits. It >> >>>>>> would make the uapi kinda crazy if we allow the user to specify >> >>>>>> BT.2020 RGB but then we actually signal BT.2020 YCbCr in the >> >>>>>> infoframe, or vice versa. Or we just signal a totally invalid value for all the >other cases. >> >>>>> I agree we need data format also to be send along with >> >>>>> colorspace, but they are 2 different things. To handle YCbCr and >> >>>>> variants (YUV 444, 420 or 422) and RGB I feel we should expose a >> >>>>> different API instead of using this one. We can create an output csc property >which does that job for us. >> >>>>> >> >>>>> So from a user perspective if we wants to set a colorspace we >> >>>>> should use the one in this series and set the data format >> >>>>> separately using the other interface. Both will be received in the state >variables and later Infoframe packet will be created accordingly. >> >>>>> Clubbing both in one may lead to lot of possible combinations >> >>>>> exposed as enum which may not look too clean. >> >>>>> >> >>>>> What do you say about handling that in the output csc property. >> >>>>> I will go with what you recommend . >> >>>> Programming Y2Y1Y0 is already taken care of, when we added support for >YCBCR outputs (4:2:0 implementation). >> >>>> In intel_hdmi.c:intel_hdmi_set_avi_infoframe(): >> >>>> >> >>>> if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420) >> >>>> frame.avi.colorspace = HDMI_COLORSPACE_YUV420; else if >> >>>> (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR444) >> >>>> frame.avi.colorspace = HDMI_COLORSPACE_YUV444; else >> >>>> frame.avi.colorspace = HDMI_COLORSPACE_RGB; >> >>>> >> >>>> IMO This looks like a better way to handle this, ie while adding support for a >new format, add support for corresponding AVI IF fileds. This will also make scope of >the property under discussion less complicated. >> >>> That's an exceptional case. We're programming the CSC in that case >> >>> to do the RGB->YCbCr conversion without telling userspace. So we >> >>> must also configure the Y bits automagically. >> >>> >> >>> What we want is a check like so: >> >>> >> >>> if (prop.colorspace != default && output_format != RGB) >> >>> return -INVAL; >> >>> >> >>> because we can't set up the CSC to make a mess of the user's >> >>> carefully crafted pixels. The pixels might not even contain RGB >> >>> data in that case. >> >>> >> >>> We'll need to extend that a little bit once we add the explicit >> >>> control of the output CSC via another prop. But the same principle >> >>> should hold. >> >> In fact, I remember the reason why we created infrastructure like >> >> this, so that, going forward, we could just add a output_format >> >> property, for which, we already have the backed and the state >> >> variables ready. The consume of this backend can be this >> >> drm_property (like output_format), or internal modeset like >> >> YCBCR4:2:0 only modes in EDID. It will also be inline with your suggestion of CSC >property. >> >> >> >> So we can have two properties colorspace (BT2020/SRGB/REC709) and >> >> color_model/color_format(RGB/YCBCR444/420), and a combination of >> >> both should program the output AVI info-frames. Does it appeal you ? >> > I'm not sure it's feasible to split it like that. The combinations >> > supported by the infoframe are rather specific so trying to split it >> > up leads to either super limited uapi, or one that exposes a lot of >> > illegal combinations. Also DP has slightly different set of things >> > it supports which adds more complications. >> > >> > So I think the best option is still to include the Y=yes/no >> > information in the prop value alognside the C/EC/ACE bits. >> >> Yes, you are right, this could be a simpler way of doing things, but >> with a limited set of combination. >> >> Consider this example: >> >> - If a HDMI monitor supports BT2020, but doesn't support YCBCR >> formatting, how to handle this option ? This means we have to >> selectively show BT2020_RGB enum value only not BT2020_YCBCR_444/420, >> >> - This also means we have to probe the EDID first, and then create >> this property, which means we will be dependent on the hot-plug / >> detect to create this property, instead of doing this in hdmi_init. > >IMO we just ignore this problem and expose all the legal options the spec has. > >If userspace wants to know what's actually supported it will have to parse the EDID. >We could think about parsing that in the kernel too and exposing an immutable prop >to expose that infromation. But I'm not sure this is such a good idea since we'd >basically drown in properties if we try to expose all the information from the EDID. A >better long term plan would be a common EDID parsing library for everyone. > >> >> Even more complex scenario would be when the output support depends on >> monitor + platform both. This means we have to provide this >> combination upfront while creating this property. >> >> On the other hand, the invalid combination of two property, it would >> be easy to detect at runtime at atomic_check() and fail the commit. >> >> >> This is just a thought, honestly I am also not sure what would be the >> most appropriate solution for this, but seems its simpler to create >> property with two properties, might be difficult to manage at runtime. >> >> With one property, its very difficult to create, but once created, it >> would work sure shot. > >I don't think it's that difficult. Just expose all the things in the >CTA-861 big table. Which means including the Y bit too. Hi Ville, Ok So will try to do this way then: Have a separate enum option like DRM_MODE_COLORIMETRY_BT709_YUV444 DRM_MODE_COLORIMETRY_BT709_YUV420 DRM_MODE_COLORIMETRY_BT709_YUV422 and so on for all the others. Expectation from userspace will be that he should be having content as per above Data format and colorspace and also should be aware that sink is supporting that which can be obtained from EDID. In driver we will check this and set the appropriate bits of infoframe and send. Regards, Uma Shankar > >-- >Ville Syrjälä >Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
