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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-08 08:23:15 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-08 08:23:15 -0800
commit851ca779d110f694b5d078bc4af06d3ad37169e8 (patch)
tree3d03de09e44ef02a6f73924f32fa21646347e64e /Documentation/gpu/afbc.rst
parentb5dd0c658c31b469ccff1b637e5124851e7a4a1c (diff)
parent4b057e73f28f1df13b77b77a52094238ffdf8abd (diff)
Merge tag 'drm-next-2019-03-06' of git://anongit.freedesktop.org/drm/drm
Pull drm updates from Dave Airlie: "This is the main drm pull request for the 5.1 merge window. The big changes I'd highlight are: - nouveau has HMM support now, there is finally an in-tree user so we can quieten down the rip it out people. - i915 now enables fastboot by default on Skylake+ - Displayport Multistream support has been refactored and should hopefully be more reliable. Core: - header cleanups aiming towards removing drmP.h - dma-buf fence seqnos to 64-bits - common helper for DP mst hotplug for radeon,i915,amdgpu + new refcounting scheme - MST i2c improvements - drm_syncobj_cb removal - ARM FB compression fourcc - P010 + P016 fourcc - allwinner tiled format modifier - i2c over aux I2C_M_STOP support - DRM_AUTH handling fixes TTM: - ref/unref renaming New driver: - ARM komeda display driver scheduler: - refactor mirror list handling - rework hw fence processing - 0 run queue entity fix bridge: - TI DS90C185 LVDS bridge - thc631lvdm83d bridge improvements - cadence + allwinner DSI ported to generic phy panels: - Sitronix ST7701 panel - Kingdisplay KD097D04 - LeMaker BL035-RGB-002 - PDA 91-00156-A0 - Innolux EE101IA-01D i915: - Enable fastboot by default on SKL+/VLV/CHV - Export RPCS configuration for ICL media driver - Coffelake PCI ID - CNL clocks setup fixes - ACPI/PMIC support for MIPI/DSI - Per-engine WA init for all engines - Shrinker locking fixes - Kerneldoc updates - Lots of ring improvements and reset fixes - Coffeelake GVT Support - VFIO GVT EDID Region support - runtime PM wakeref tracking - ILK->IVB primary plane enable delays - userptr mutex locking fixes - DSI fixes - LVDS/TV cleanups - HW readout fixes - LUT robustness fixes - ICL display and watermark fixes - gem mmap race fix amdgpu: - add scheduled dependencies interface - DCC on scanout surfaces - vega10/20 BACO support - Multiple IH rings on soc15 - XGMI locking fixes - DC i2c/aux cleanups - runtime SMU debug interface - Kexec improvmeents - SR-IOV fixes - DC freesync + ABM fixes - GDS fixes - GPUVM fixes - vega20 PCIE DPM switching fixes - Context priority handling fixes radeon: - fix missing break in evergreen parser nouveau: - SVM support via HMM msm: - QCOM Compressed modifier support exynos: - s5pv210 rotator support imx: - zpos property support - pending update fixes v3d: - cache flush improvments vc4: - reflection support - HDMI overscan support tegra: - CEC refactoring - HDMI audio fixes - Tegra186 prep work - SOR crossbar device tree fixes sun4i: - implicit fencing support - YUV and scalar support improvements - A23 support - tiling fixes atmel-hlcdc: - clipping and rotation property fixes qxl: - BO and PRIME improvements - generic fbdev emulation dw-hdmi: - HDMI 2.0 2160p - YUV420 ouput rockchip: - implicit fencing support - reflection proerties virtio-gpu: - use generic fbdev emulation tilcdc: - cpufreq vs crtc init fix rcar-du: - R8A774C0 support - D3/E3 RGB output routing fixes and DPAD0 support - RA87744 LVDS support bochs: - atomic and generic fbdev emulation - ID mismatch error on bochs load meson: - remove firmware fbs" * tag 'drm-next-2019-03-06' of git://anongit.freedesktop.org/drm/drm: (1130 commits) drm/amd/display: Use vrr friendly pageflip throttling in DC. drm/imx: only send commit done event when all state has been applied drm/imx: allow building under COMPILE_TEST drm/imx: imx-tve: depend on COMMON_CLK drm/imx: ipuv3-plane: add zpos property drm/imx: ipuv3-plane: add function to query atomic update status gpu: ipu-v3: prg: add function to get channel configure status gpu: ipu-v3: pre: add double buffer status readback drm/amdgpu: Bump amdgpu version for context priority override. drm/amdgpu/powerplay: fix typo in BACO header guards drm/amdgpu/powerplay: fix return codes in BACO code drm/amdgpu: add missing license on baco files drm/bochs: Fix the ID mismatch error drm/nouveau/dmem: use dma addresses during migration copies drm/nouveau/dmem: use physical vram addresses during migration copies drm/nouveau/dmem: extend copy function to allow direct use of physical addresses drm/nouveau/svm: new ioctl to migrate process memory to GPU memory drm/nouveau/dmem: device memory helpers for SVM drm/nouveau/svm: initial support for shared virtual memory drm/nouveau: prepare for enabling svm with existing userspace interfaces ...
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+.. SPDX-License-Identifier: GPL-2.0+
+
+===================================
+ Arm Framebuffer Compression (AFBC)
+===================================
+
+AFBC is a proprietary lossless image compression protocol and format.
+It provides fine-grained random access and minimizes the amount of
+data transferred between IP blocks.
+
+AFBC can be enabled on drivers which support it via use of the AFBC
+format modifiers defined in drm_fourcc.h. See DRM_FORMAT_MOD_ARM_AFBC(*).
+
+All users of the AFBC modifiers must follow the usage guidelines laid
+out in this document, to ensure compatibility across different AFBC
+producers and consumers.
+
+Components and Ordering
+=======================
+
+AFBC streams can contain several components - where a component
+corresponds to a color channel (i.e. R, G, B, X, A, Y, Cb, Cr).
+The assignment of input/output color channels must be consistent
+between the encoder and the decoder for correct operation, otherwise
+the consumer will interpret the decoded data incorrectly.
+
+Furthermore, when the lossless colorspace transform is used
+(AFBC_FORMAT_MOD_YTR, which should be enabled for RGB buffers for
+maximum compression efficiency), the component order must be:
+
+ * Component 0: R
+ * Component 1: G
+ * Component 2: B
+
+The component ordering is communicated via the fourcc code in the
+fourcc:modifier pair. In general, component '0' is considered to
+reside in the least-significant bits of the corresponding linear
+format. For example, COMP(bits):
+
+ * DRM_FORMAT_ABGR8888
+
+ * Component 0: R(8)
+ * Component 1: G(8)
+ * Component 2: B(8)
+ * Component 3: A(8)
+
+ * DRM_FORMAT_BGR888
+
+ * Component 0: R(8)
+ * Component 1: G(8)
+ * Component 2: B(8)
+
+ * DRM_FORMAT_YUYV
+
+ * Component 0: Y(8)
+ * Component 1: Cb(8, 2x1 subsampled)
+ * Component 2: Cr(8, 2x1 subsampled)
+
+In AFBC, 'X' components are not treated any differently from any other
+component. Therefore, an AFBC buffer with fourcc DRM_FORMAT_XBGR8888
+encodes with 4 components, like so:
+
+ * DRM_FORMAT_XBGR8888
+
+ * Component 0: R(8)
+ * Component 1: G(8)
+ * Component 2: B(8)
+ * Component 3: X(8)
+
+Please note, however, that the inclusion of a "wasted" 'X' channel is
+bad for compression efficiency, and so it's recommended to avoid
+formats containing 'X' bits. If a fourth component is
+required/expected by the encoder/decoder, then it is recommended to
+instead use an equivalent format with alpha, setting all alpha bits to
+'1'. If there is no requirement for a fourth component, then a format
+which doesn't include alpha can be used, e.g. DRM_FORMAT_BGR888.
+
+Number of Planes
+================
+
+Formats which are typically multi-planar in linear layouts (e.g. YUV
+420), can be encoded into one, or multiple, AFBC planes. As with
+component order, the encoder and decoder must agree about the number
+of planes in order to correctly decode the buffer. The fourcc code is
+used to determine the number of encoded planes in an AFBC buffer,
+matching the number of planes for the linear (unmodified) format.
+Within each plane, the component ordering also follows the fourcc
+code:
+
+For example:
+
+ * DRM_FORMAT_YUYV: nplanes = 1
+
+ * Plane 0:
+
+ * Component 0: Y(8)
+ * Component 1: Cb(8, 2x1 subsampled)
+ * Component 2: Cr(8, 2x1 subsampled)
+
+ * DRM_FORMAT_NV12: nplanes = 2
+
+ * Plane 0:
+
+ * Component 0: Y(8)
+
+ * Plane 1:
+
+ * Component 0: Cb(8, 2x1 subsampled)
+ * Component 1: Cr(8, 2x1 subsampled)
+
+Cross-device interoperability
+=============================
+
+For maximum compatibility across devices, the table below defines
+canonical formats for use between AFBC-enabled devices. Formats which
+are listed here must be used exactly as specified when using the AFBC
+modifiers. Formats which are not listed should be avoided.
+
+.. flat-table:: AFBC formats
+
+ * - Fourcc code
+ - Description
+ - Planes/Components
+
+ * - DRM_FORMAT_ABGR2101010
+ - 10-bit per component RGB, with 2-bit alpha
+ - Plane 0: 4 components
+ * Component 0: R(10)
+ * Component 1: G(10)
+ * Component 2: B(10)
+ * Component 3: A(2)
+
+ * - DRM_FORMAT_ABGR8888
+ - 8-bit per component RGB, with 8-bit alpha
+ - Plane 0: 4 components
+ * Component 0: R(8)
+ * Component 1: G(8)
+ * Component 2: B(8)
+ * Component 3: A(8)
+
+ * - DRM_FORMAT_BGR888
+ - 8-bit per component RGB
+ - Plane 0: 3 components
+ * Component 0: R(8)
+ * Component 1: G(8)
+ * Component 2: B(8)
+
+ * - DRM_FORMAT_BGR565
+ - 5/6-bit per component RGB
+ - Plane 0: 3 components
+ * Component 0: R(5)
+ * Component 1: G(6)
+ * Component 2: B(5)
+
+ * - DRM_FORMAT_ABGR1555
+ - 5-bit per component RGB, with 1-bit alpha
+ - Plane 0: 4 components
+ * Component 0: R(5)
+ * Component 1: G(5)
+ * Component 2: B(5)
+ * Component 3: A(1)
+
+ * - DRM_FORMAT_VUY888
+ - 8-bit per component YCbCr 444, single plane
+ - Plane 0: 3 components
+ * Component 0: Y(8)
+ * Component 1: Cb(8)
+ * Component 2: Cr(8)
+
+ * - DRM_FORMAT_VUY101010
+ - 10-bit per component YCbCr 444, single plane
+ - Plane 0: 3 components
+ * Component 0: Y(10)
+ * Component 1: Cb(10)
+ * Component 2: Cr(10)
+
+ * - DRM_FORMAT_YUYV
+ - 8-bit per component YCbCr 422, single plane
+ - Plane 0: 3 components
+ * Component 0: Y(8)
+ * Component 1: Cb(8, 2x1 subsampled)
+ * Component 2: Cr(8, 2x1 subsampled)
+
+ * - DRM_FORMAT_NV16
+ - 8-bit per component YCbCr 422, two plane
+ - Plane 0: 1 component
+ * Component 0: Y(8)
+ Plane 1: 2 components
+ * Component 0: Cb(8, 2x1 subsampled)
+ * Component 1: Cr(8, 2x1 subsampled)
+
+ * - DRM_FORMAT_Y210
+ - 10-bit per component YCbCr 422, single plane
+ - Plane 0: 3 components
+ * Component 0: Y(10)
+ * Component 1: Cb(10, 2x1 subsampled)
+ * Component 2: Cr(10, 2x1 subsampled)
+
+ * - DRM_FORMAT_P210
+ - 10-bit per component YCbCr 422, two plane
+ - Plane 0: 1 component
+ * Component 0: Y(10)
+ Plane 1: 2 components
+ * Component 0: Cb(10, 2x1 subsampled)
+ * Component 1: Cr(10, 2x1 subsampled)
+
+ * - DRM_FORMAT_YUV420_8BIT
+ - 8-bit per component YCbCr 420, single plane
+ - Plane 0: 3 components
+ * Component 0: Y(8)
+ * Component 1: Cb(8, 2x2 subsampled)
+ * Component 2: Cr(8, 2x2 subsampled)
+
+ * - DRM_FORMAT_YUV420_10BIT
+ - 10-bit per component YCbCr 420, single plane
+ - Plane 0: 3 components
+ * Component 0: Y(10)
+ * Component 1: Cb(10, 2x2 subsampled)
+ * Component 2: Cr(10, 2x2 subsampled)
+
+ * - DRM_FORMAT_NV12
+ - 8-bit per component YCbCr 420, two plane
+ - Plane 0: 1 component
+ * Component 0: Y(8)
+ Plane 1: 2 components
+ * Component 0: Cb(8, 2x2 subsampled)
+ * Component 1: Cr(8, 2x2 subsampled)
+
+ * - DRM_FORMAT_P010
+ - 10-bit per component YCbCr 420, two plane
+ - Plane 0: 1 component
+ * Component 0: Y(10)
+ Plane 1: 2 components
+ * Component 0: Cb(10, 2x2 subsampled)
+ * Component 1: Cr(10, 2x2 subsampled)