Re: [PATCH 00/36] drm/amd/display: add AMD driver-specific properties for color mgmt

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On 24/05/2023 01:14, Melissa Wen wrote:
> This series is a refined version of our RFC [1] for AMD driver-specific
> color management properties. It is a collection of contributions from
> Joshua, Harry and I to enhance AMD KMS color pipeline for Steam
> Deck/SteamOS by exposing the large set of color caps available in AMD
> display HW.
> 
> Considering RFC feedback, this patchset differs from the previous one by
> removing the KConfig option and just guarding driver-specific properties
> with `AMD_PRIVATE_COLOR` - but we also removed the guards from internal
> elements and operations. We stopped to advertise CRTC shaper and 3D LUTs
> properties since they aren't in use in the Steam Deck color pipeline[2].
> On the other hand, we keep mapping CRTC shaper and 3D LUTs (DM) to DC
> MPC setup. We also improved curve calculations to take into account HW
> color caps.
> 
> In short, for pre-blending, we added the following properties:
> - plane degamma LUT and predefined transfer function;
> - plane HDR multiplier
> - plane shaper LUT/transfer function;
> - plane 3D LUT; and finally,
> - plane blend LUT/transfer function, just before blending.

This set of properties sounds interesting and not fully AMD-specific. 
Could you please consider moving them to the more generic location?

For the reference, MSM (Qualcomm) display hardware supports 
degamma/gamma LUTs for planes too. One of the suggested usecases for 
these degamma/gamma units is to support colorspace transfer functions.

Thus, at least some of these properties can be implemented in drm/msm 
driver too.

> After blending, we already have DRM CRTC degamma/gamma LUTs and CTM,
> therefore, we extend post-blending color pipeline with CRTC gamma
> transfer function.
> 
> The first three patches are on DRM KMS side. We expose DRM property
> helper for blob lookup and replacement so that we can use it for
> managing driver-specific properties. We add a tracked for plane color
> mgmt changes and increase the maximum number of properties to
> accommodate this expansion.
> 
> The userspace case here is Gamescope which is the compositor for
> SteamOS. It's already using all of this functionality to implement its
> color management pipeline right now [3].
> 
> Current IGT tests kms_color and amdgpu/amd_color on DCN301 and DCN21 HW
> preserve the same results with and without the guard.
> 
> Finally, I may have missed something, please let me know if that's the
> case.
> 
> Best Regards,
> 
> Melissa Wen
> 
> [1] https://lore.kernel.org/dri-devel/20230423141051.702990-1-mwen@igalia.com
> [2] https://github.com/ValveSoftware/gamescope/blob/master/src/docs/Steam%20Deck%20Display%20Pipeline.png
> [3] https://github.com/ValveSoftware/gamescope
> 
> 
> Harry Wentland (2):
>    drm/amd/display: fix segment distribution for linear LUTs
>    drm/amd/display: fix the delta clamping for shaper LUT
> 
> Joshua Ashton (13):
>    drm/amd/display: add plane degamma TF driver-specific property
>    drm/amd/display: add plane HDR multiplier driver-specific property
>    drm/amd/display: add plane blend LUT and TF driver-specific properties
>    drm/amd/display: copy 3D LUT settings from crtc state to stream_update
>    drm/amd/display: dynamically acquire 3DLUT resources for color changes
>    drm/amd/display: add CRTC regamma TF support
>    drm/amd/display: set sdr_ref_white_level to 80 for out_transfer_func
>    drm/amd/display: add support for plane degamma TF and LUT properties
>    drm/amd/display: add dc_fixpt_from_s3132 helper
>    drm/adm/display: add HDR multiplier support
>    drm/amd/display: handle empty LUTs in __set_input_tf
>    drm/amd/display: add DRM plane blend LUT and TF support
>    drm/amd/display: allow newer DC hardware to use degamma ROM for PQ/HLG
> 
> Melissa Wen (21):
>    drm/drm_mode_object: increase max objects to accommodate new color
>      props
>    drm/drm_property: make replace_property_blob_from_id a DRM helper
>    drm/drm_plane: track color mgmt changes per plane
>    drm/amd/display: add CRTC driver-specific property for gamma TF
>    drm/amd/display: add plane driver-specific properties for degamma LUT
>    drm/amd/display: add plane 3D LUT driver-specific properties
>    drm/amd/display: add plane shaper LUT driver-specific properties
>    drm/amd/display: add plane shaper TF driver-private property
>    drm/amd/display: add comments to describe DM crtc color mgmt behavior
>    drm/amd/display: encapsulate atomic regamma operation
>    drm/amd/display: update lut3d and shaper lut to stream
>    drm/amd/display: allow BYPASS 3D LUT but keep shaper LUT settings
>    drm/amd/display: handle MPC 3D LUT resources for a given context
>    drm/amd/display: add CRTC 3D LUT support
>    drm/amd/display: add CRTC shaper LUT support
>    drm/amd/display: add CRTC shaper TF support
>    drm/amd/display: mark plane as needing reset if plane color mgmt
>      changes
>    drm/amd/display: decouple steps for mapping CRTC degamma to DC plane
>    drm/amd/display: reject atomic commit if setting both plane and CRTC
>      degamma
>    drm/amd/display: program DPP shaper and 3D LUT if updated
>    drm/amd/display: add plane shaper/3D LUT and shaper TF support
> 
>   drivers/gpu/drm/amd/amdgpu/amdgpu_display.c   | 125 ++++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h      |  69 ++
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c |  28 +-
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 110 +++-
>   .../amd/display/amdgpu_dm/amdgpu_dm_color.c   | 612 ++++++++++++++++--
>   .../amd/display/amdgpu_dm/amdgpu_dm_crtc.c    |  72 ++-
>   .../amd/display/amdgpu_dm/amdgpu_dm_plane.c   | 213 +++++-
>   drivers/gpu/drm/amd/display/dc/core/dc.c      |  49 +-
>   drivers/gpu/drm/amd/display/dc/dc.h           |   8 +
>   .../amd/display/dc/dcn10/dcn10_cm_common.c    | 107 ++-
>   .../drm/amd/display/dc/dcn20/dcn20_hwseq.c    |   5 +-
>   .../drm/amd/display/dc/dcn30/dcn30_hwseq.c    |   9 +-
>   .../amd/display/dc/dcn301/dcn301_resource.c   |  26 +-
>   .../gpu/drm/amd/display/include/fixed31_32.h  |  12 +
>   drivers/gpu/drm/arm/malidp_crtc.c             |   2 +-
>   drivers/gpu/drm/drm_atomic.c                  |   1 +
>   drivers/gpu/drm/drm_atomic_state_helper.c     |   1 +
>   drivers/gpu/drm/drm_atomic_uapi.c             |  43 +-
>   drivers/gpu/drm/drm_property.c                |  49 ++
>   include/drm/drm_mode_object.h                 |   2 +-
>   include/drm/drm_plane.h                       |   7 +
>   include/drm/drm_property.h                    |   6 +
>   22 files changed, 1416 insertions(+), 140 deletions(-)
> 

-- 
With best wishes
Dmitry