[Intel-gfx] [PATCH v4 2/2] drm: Add HDMI 2.0 VIC support for AVI info-frames

[Jose Abreu]

Hi Ville,


On 23-03-2017 15:36, Ville Syrjälä wrote:
> On Thu, Mar 23, 2017 at 05:14:19PM +0200, Shashank Sharma wrote:
>> HDMI 1.4b support the CEA video modes as per range of CEA-861-D (VIC 1-64).
>> For any other mode, the VIC filed in AVI infoframes should be 0.
>> HDMI 2.0 sinks, support video modes range as per CEA-861-F spec, which is
>> extended to (VIC 1-107).
>>
>> This patch adds a bool input variable, which indicates if the connected
>> sink is a HDMI 2.0 sink or not. This will make sure that we don't pass a
>> HDMI 2.0 VIC to a HDMI 1.4 sink.
> The spec is unfortunately vague when it comes to the CEA-861-F VIC
> transmission when there is a corresponding HDMI VIC for the same mode.
> I'm not sure if it's telling us to set both or just one depending on
> whether we're transmitting 3D video or not. Or at least I can't parse
> that information from the spec. Anyone have a better crystal ball
> in their possession?
>

I've been working in HDMI receivers and this is what I've got in
a comment:

1282        
/*                                                                                                       

1283          * Update current VIC: When transmitting any
extended video format                                       
1284          * indicated through use of the HDMI_VIC field in
the HDMI Vendor                                        
1285          * Specific InfoFrame or any other format which is
not described in                                      
1286          * the above cases, an HDMI Source shall set the AVI
InfoFrame VIC                                       
1287          * field to
zero.                                                                                        

1288          */

This was directly taken from the spec, can't remember exactly
were though.

So, the VIC in AVIIF must be set to 0 and the HDMI_VIC field in
VSIF shall be set to the HDMI 4k VIC.

Best regards,
Jose Miguel Abreu