This is how a typical display color hardware pipeline looks like: +-------------------------------------------+ | RAM | | +------+ +---------+ +---------+ | | | FB 1 | | FB 2 | | FB N | | | +------+ +---------+ +---------+ | +-------------------------------------------+ | Plane Color Hardware Block | +--------------------------------------------+ | +---v-----+ +---v-------+ +---v------+ | | | Plane A | | Plane B | | Plane N | | | | DeGamma | | Degamma | | Degamma | | | +---+-----+ +---+-------+ +---+------+ | | | | | | | +---v-----+ +---v-------+ +---v------+ | | |Plane A | | Plane B | | Plane N | | | |CSC/CTM | | CSC/CTM | | CSC/CTM | | | +---+-----+ +----+------+ +----+-----+ | | | | | | | +---v-----+ +----v------+ +----v-----+ | | | Plane A | | Plane B | | Plane N | | | | Gamma | | Gamma | | Gamma | | | +---+-----+ +----+------+ +----+-----+ | | | | | | +--------------------------------------------+ +------v--------------v---------------v-------| || || || Pipe Blender || +--------------------+------------------------+ | | | | +-----------v----------+ | | | Pipe DeGamma | | | | | | | +-----------+----------+ | | | Pipe Color | | +-----------v----------+ Hardware | | | Pipe CSC/CTM | | | | | | | +-----------+----------+ | | | | | +-----------v----------+ | | | Pipe Gamma | | | | | | | +-----------+----------+ | | | | +---------------------------------------------+ | v Pipe Output
This patch series adds properties for plane color features. It adds properties for degamma used to linearize data, CSC used for gamut conversion, and gamma used to again non-linearize data as per panel supported color space. These can be utilize by user space to convert planes from one format to another, one color space to another etc.
Usersapce can take smart blending decisions and utilize these hardware supported plane color features to get accurate color profile. The same can help in consistent color quality from source to panel taking advantage of advanced color features in hardware.
These patches just add the property interfaces and enable helper functions.
This series adds Intel Gen9 specific plane gamma feature. We can build up and add other platform/hardware specific implementation on top of this series
Note: This is just to get a design feedback whether these interfaces look ok. Based on community feedback on interfaces, we will implement IGT tests to validate plane color features. This is un-tested currently.
Userspace implementation using these properties have been done in drm hwcomposer by "Alexandru-Cosmin Gheorghe Alexandru-Cosmin.Gheorghe@arm.com" from ARM. A merge request has been opened by Alexandru for drm_hwcomposer, implementing the property changes for the same. Please review that as well: https://gitlab.freedesktop.org/drm-hwcomposer/drm-hwcomposer/merge_requests/...
v2: Dropped legacy gamma table for plane as suggested by Maarten. Added Gen9/BDW plane gamma feature and rebase on tot.
v3: Added a new drm_color_lut_ext structure to accommodate 32 bit precision entries, pointed to by Brian, Starkey for HDR usecases. Addressed Sean,Paul comments and moved plane color properties to drm_plane instead of mode_config. Added property documentation as suggested by Daniel, Vetter. Fixed a rebase fumble which occurred in v2, pointed by Emil Velikov.
v4: Rebase
v5: Added "Display Color Hardware Pipeline" flow to kernel documentation as suggested by "Ville Syrjala" and "Brian Starkey". Moved the property creation to drm_color_mgmt.c file to consolidate all color operations at one place. Addressed Alexandru's review comments.
v6: Rebase. Added support for ICL Color features. Enhanced Lut precision to accept input values in u32.32 format. This is needed for higher precision required in HDR data processing.
v7: Fixed Lut roundup and extraction function in patch 1 and address definitions for Degamma index in patch 10. Rest of the patches are just rebased.
Uma Shankar (16): drm: Add Enhanced Gamma LUT precision structure drm: Add Plane Degamma properties drm: Add Plane CTM property drm: Add Plane Gamma properties drm: Define helper function for plane color enabling drm/i915: Enable plane color features drm/i915: Implement Plane Gamma for Bdw and Gen9 platforms drm/i915: Load plane color luts from atomic flip drm/i915: Add plane color capabilities drm/i915/icl: Add ICL Plane Degamma Register definition drm/i915/icl: Enable Plane Degamma drm/i915/icl: Add Plane Gamma Register Definitions drm/i915/icl: Implement Plane Gamma drm/i915: Enable Plane Gamma/Degamma drm/i915: Define Plane CSC Registers drm/i915: Enable Plane CSC
Documentation/gpu/drm-kms.rst | 99 +++++++++ drivers/gpu/drm/drm_atomic.c | 1 + drivers/gpu/drm/drm_atomic_state_helper.c | 12 ++ drivers/gpu/drm/drm_atomic_uapi.c | 29 +++ drivers/gpu/drm/drm_color_mgmt.c | 138 ++++++++++++- drivers/gpu/drm/i915/i915_drv.h | 6 + drivers/gpu/drm/i915/i915_pci.c | 5 +- drivers/gpu/drm/i915/i915_reg.h | 153 ++++++++++++++ drivers/gpu/drm/i915/intel_atomic_plane.c | 3 + drivers/gpu/drm/i915/intel_color.c | 331 ++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_device_info.h | 5 + drivers/gpu/drm/i915/intel_display.c | 13 +- drivers/gpu/drm/i915/intel_drv.h | 11 + drivers/gpu/drm/i915/intel_sprite.c | 11 + include/drm/drm_color_mgmt.h | 6 + include/drm/drm_plane.h | 61 ++++++ include/uapi/drm/drm_mode.h | 15 ++ 17 files changed, 894 insertions(+), 5 deletions(-)