Arm Fixed Rate Compression (AFRC) is a proprietary fixed rate image compression protocol and format. It is designed to provide guaranteed bandwidth and memory footprint reductions in graphics and media use-cases.
This patch aims to add modifier definitions for describing AFRC.
Signed-off-by: Normunds Rieksts normunds.rieksts@arm.com --- include/uapi/drm/drm_fourcc.h | 109 +++++++++++++++++++++++++++++++++- 1 file changed, 106 insertions(+), 3 deletions(-)
diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h index f7156322aba5..9f4bb4a6f358 100644 --- a/include/uapi/drm/drm_fourcc.h +++ b/include/uapi/drm/drm_fourcc.h @@ -900,9 +900,9 @@ drm_fourcc_canonicalize_nvidia_format_mod(__u64 modifier)
/* * The top 4 bits (out of the 56 bits alloted for specifying vendor specific - * modifiers) denote the category for modifiers. Currently we have only two - * categories of modifiers ie AFBC and MISC. We can have a maximum of sixteen - * different categories. + * modifiers) denote the category for modifiers. Currently we have three + * categories of modifiers ie AFBC, MISC and AFRC. We can have a maximum of + * sixteen different categories. */ #define DRM_FORMAT_MOD_ARM_CODE(__type, __val) \ fourcc_mod_code(ARM, ((__u64)(__type) << 52) | ((__val) & 0x000fffffffffffffULL)) @@ -1017,6 +1017,109 @@ drm_fourcc_canonicalize_nvidia_format_mod(__u64 modifier) */ #define AFBC_FORMAT_MOD_USM (1ULL << 12)
+/* + * Arm Fixed-Rate Compression (AFRC) modifiers + * + * AFRC is a proprietary fixed rate image compression protocol and format, + * designed to provide guaranteed bandwidth and memory footprint + * reductions in graphics and media use-cases. + * + * AFRC buffers consist of one or more planes, with the same components + * and meaning as an uncompressed buffer using the same pixel format. + * + * Within each plane, the pixel/luma/chroma values are grouped into + * "coding unit" blocks which are individually compressed to a + * fixed size (in bytes). All coding units within a given plane of a buffer + * store the same number of values, and have the same compressed size. + * + * The coding unit size is configurable, allowing different rates of compression. + * + * The start of each AFRC buffer plane must be aligned to an alignment granule which + * depends on the coding unit size. + * + * Coding Unit Size Plane Alignment + * ---------------- --------------- + * 16 bytes 1024 bytes + * 24 bytes 512 bytes + * 32 bytes 2048 bytes + * + * Coding units are grouped into paging tiles. AFRC buffer dimensions must be aligned + * to a multiple of the paging tile dimensions. + * The dimensions of each paging tile depend on whether the buffer is optimised for + * scanline (SCAN layout) or rotated (ROT layout) access. + * + * Layout Paging Tile Width Paging Tile Height + * ------ ----------------- ------------------ + * SCAN 16 coding units 4 coding units + * ROT 8 coding units 8 coding units + * + * The dimensions of each coding unit depend on the number of components + * in the compressed plane and whether the buffer is optimised for + * scanline (SCAN layout) or rotated (ROT layout) access. + * + * Number of Components in Plane Layout Coding Unit Width Coding Unit Height + * ----------------------------- --------- ----------------- ------------------ + * 1 SCAN 16 samples 4 samples + * Example: 16x4 luma samples in a 'Y' plane + * 16x4 chroma 'V' values, in the 'V' plane of a fully-planar YUV buffer + * ----------------------------- --------- ----------------- ------------------ + * 1 ROT 8 samples 8 samples + * Example: 8x8 luma samples in a 'Y' plane + * 8x8 chroma 'V' values, in the 'V' plane of a fully-planar YUV buffer + * ----------------------------- --------- ----------------- ------------------ + * 2 DONT CARE 8 samples 4 samples + * Example: 8x4 chroma pairs in the 'UV' plane of a semi-planar YUV buffer + * ----------------------------- --------- ----------------- ------------------ + * 3 DONT CARE 4 samples 4 samples + * Example: 4x4 pixels in an RGB buffer without alpha + * ----------------------------- --------- ----------------- ------------------ + * 4 DONT CARE 4 samples 4 samples + * Example: 4x4 pixels in an RGB buffer with alpha + */ + +#define DRM_FORMAT_MOD_ARM_TYPE_AFRC 0x02 + +#define DRM_FORMAT_MOD_ARM_AFRC(__afrc_mode) \ + DRM_FORMAT_MOD_ARM_CODE(DRM_FORMAT_MOD_ARM_TYPE_AFRC, __afrc_mode) + +/* + * AFRC coding unit size modifier. + * + * Indicates the number of bytes used to store each compressed coding unit for + * one or more planes in an AFRC encoded buffer. The coding unit size for chrominance + * is the same for both Cb and Cr, which may be stored in separate planes. + * + * AFRC_FORMAT_MOD_CU_SIZE_P0 indicates the number of bytes used to store + * each compressed coding unit in the first plane of the buffer. For RGBA buffers + * this is the only plane, while for semi-planar and fully-planar YUV buffers, + * this corresponds to the luma plane. + * + * AFRC_FORMAT_MOD_CU_SIZE_P12 indicates the number of bytes used to store + * each compressed coding unit in the second and third planes in the buffer. + * For semi-planar and fully-planar YUV buffers, this corresponds to the chroma plane(s). + * + * For single-plane buffers, AFRC_FORMAT_MOD_CU_SIZE_P0 must be specified + * and AFRC_FORMAT_MOD_CU_SIZE_P12 must be zero. + * For semi-planar and fully-planar buffers, both AFRC_FORMAT_MOD_CU_SIZE_P0 and + * AFRC_FORMAT_MOD_CU_SIZE_P12 must be specified. + */ +#define AFRC_FORMAT_MOD_CU_SIZE_MASK 0xf +#define AFRC_FORMAT_MOD_CU_SIZE_16 (1ULL) +#define AFRC_FORMAT_MOD_CU_SIZE_24 (2ULL) +#define AFRC_FORMAT_MOD_CU_SIZE_32 (3ULL) + +#define AFRC_FORMAT_MOD_CU_SIZE_P0(__afrc_cu_size) (__afrc_cu_size) +#define AFRC_FORMAT_MOD_CU_SIZE_P12(__afrc_cu_size) ((__afrc_cu_size) << 4) + +/* + * AFRC scanline memory layout. + * + * Indicates if the buffer uses the scanline-optimised layout + * for an AFRC encoded buffer, otherwise, it uses the rotation-optimised layout. + * The memory layout is the same for all planes. + */ +#define AFRC_FORMAT_MOD_LAYOUT_SCAN (1ULL << 8) + /* * Arm 16x16 Block U-Interleaved modifier *