[Intel-gfx] [PATCH 00/20] drm/i915: Fix up DP DFP 4:2:0 handling more

[Nautiyal, Ankit K]

Hi Ville,

Thanks for the patch and getting a unified approach for DP, HDMI and DFP 
for YCbCr420 output.

I am trying to have 8k at 60 YUV420 via an HDMI2.1 PCON, without having to 
use PCONs Color conversion capability,

but running into different issues, and failing miserably. I think this 
patch series will help get there.

There are a couple of queries and suggestions I have regarding the big 
joiner and DSC, which I'll reply to the patches.

I will also try to test these on the setup I have available.

Thanks & Regards,

Ankit

On 10/15/2021 7:09 PM, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>
> Currently we're failing to respect the sink's max TMDS clock
> in the DP HDMI DFP code, and exceeding them means the sink
> won't show a picture [1]. So let's improve the situation by
> checking those limits, and generally fixing up a bunch things
> in the deep color/4:2:0 related stuff for both native HDMI
> and DP HDMI DFPs.
>
> The end result is fairly unified apporach to this stuff on
> both sides of the aisle. There's probably more we could try
> to abstract to share even more code. But that will need a lot
> of actual thought so leave it for later.
>
> The high level algorithm is basically now:
> for_each(respect TMDS clock limits, disrespect TMDS clock limits)
> 	for_each(YCbCr 4:2:0 only, RGB 4:4:4, YCbCr 4:2:0 also)
> 		for_each(12bpc,10bpc,8bpc)
> 			compute_and_check_the_things
> with some obvious tweaks for HDMI vs. DP specifics.
>
> [1] https://gitlab.freedesktop.org/drm/intel/-/issues/4095
>
> Ville Syrjälä (20):
>    drm/i915/hdmi: Split intel_hdmi_bpc_possible() to source vs. sink pair
>    drm/i915/hdmi: Introduce intel_hdmi_is_ycbr420()
>    drm/i915/hdmi: Introduce intel_hdmi_tmds_clock()
>    drm/i915/hdmi: Unify "4:2:0 also" logic between .mode_valid() and
>      .compute_config()
>    drm/i915/hdmi: Extract intel_hdmi_output_format()
>    drm/i915/hdmi: Clean up TMDS clock limit exceeding user mode handling
>    drm/i915/hdmi: Simplify intel_hdmi_mode_clock_valid()
>    drm/i915/dp: Reuse intel_hdmi_tmds_clock()
>    drm/i915/dp: Extract intel_dp_tmds_clock_valid()
>    drm/i915/dp: Respect the sink's max TMDS clock when dealing with
>      DP->HDMI DFPs
>    drm/i915/dp: Extract intel_dp_has_audio()
>    drm/i915/dp: s/intel_dp_hdmi_ycbcr420/intel_dp_is_ycbcr420/
>    drm/i915/dp: Reorder intel_dp_compute_config() a bit
>    drm/i915/dp: Pass around intel_connector rather than drm_connector
>    drm/i915/dp: Make intel_dp_output_format() usable for "4:2:0 also"
>      modes
>    drm/i915/dp: Rework HDMI DFP TMDS clock handling
>    drm/i915/dp: Add support for "4:2:0 also" modes for DP
>    drm/i915/dp: Duplicate native HDMI TMDS clock limit handling for DP
>      HDMI DFPs
>    drm/i915/dp: Fix DFP rgb->ycbcr conversion matrix
>    drm/i915/dp: Disable DFP RGB->YCbCr conversion for now
>
>   drivers/gpu/drm/i915/display/intel_dp.c   | 339 +++++++++++++---------
>   drivers/gpu/drm/i915/display/intel_hdmi.c | 220 ++++++++------
>   drivers/gpu/drm/i915/display/intel_hdmi.h |   5 +-
>   3 files changed, 342 insertions(+), 222 deletions(-)
>