diff options
Diffstat (limited to 'include/standard-headers/drm')
| -rw-r--r-- | include/standard-headers/drm/drm_fourcc.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/include/standard-headers/drm/drm_fourcc.h b/include/standard-headers/drm/drm_fourcc.h index b53f8d7..4449060 100644 --- a/include/standard-headers/drm/drm_fourcc.h +++ b/include/standard-headers/drm/drm_fourcc.h @@ -29,11 +29,50 @@ extern "C" { #endif +/** + * DOC: overview + * + * In the DRM subsystem, framebuffer pixel formats are described using the + * fourcc codes defined in `include/uapi/drm/drm_fourcc.h`. In addition to the + * fourcc code, a Format Modifier may optionally be provided, in order to + * further describe the buffer's format - for example tiling or compression. + * + * Format Modifiers + * ---------------- + * + * Format modifiers are used in conjunction with a fourcc code, forming a + * unique fourcc:modifier pair. This format:modifier pair must fully define the + * format and data layout of the buffer, and should be the only way to describe + * that particular buffer. + * + * Having multiple fourcc:modifier pairs which describe the same layout should + * be avoided, as such aliases run the risk of different drivers exposing + * different names for the same data format, forcing userspace to understand + * that they are aliases. + * + * Format modifiers may change any property of the buffer, including the number + * of planes and/or the required allocation size. Format modifiers are + * vendor-namespaced, and as such the relationship between a fourcc code and a + * modifier is specific to the modifer being used. For example, some modifiers + * may preserve meaning - such as number of planes - from the fourcc code, + * whereas others may not. + * + * Vendors should document their modifier usage in as much detail as + * possible, to ensure maximum compatibility across devices, drivers and + * applications. + * + * The authoritative list of format modifier codes is found in + * `include/uapi/drm/drm_fourcc.h` + */ + #define fourcc_code(a, b, c, d) ((uint32_t)(a) | ((uint32_t)(b) << 8) | \ ((uint32_t)(c) << 16) | ((uint32_t)(d) << 24)) #define DRM_FORMAT_BIG_ENDIAN (1<<31) /* format is big endian instead of little endian */ +/* Reserve 0 for the invalid format specifier */ +#define DRM_FORMAT_INVALID 0 + /* color index */ #define DRM_FORMAT_C8 fourcc_code('C', '8', ' ', ' ') /* [7:0] C */ @@ -111,6 +150,21 @@ extern "C" { #define DRM_FORMAT_VYUY fourcc_code('V', 'Y', 'U', 'Y') /* [31:0] Y1:Cb0:Y0:Cr0 8:8:8:8 little endian */ #define DRM_FORMAT_AYUV fourcc_code('A', 'Y', 'U', 'V') /* [31:0] A:Y:Cb:Cr 8:8:8:8 little endian */ +#define DRM_FORMAT_XYUV8888 fourcc_code('X', 'Y', 'U', 'V') /* [31:0] X:Y:Cb:Cr 8:8:8:8 little endian */ + +/* + * packed YCbCr420 2x2 tiled formats + * first 64 bits will contain Y,Cb,Cr components for a 2x2 tile + */ +/* [63:0] A3:A2:Y3:0:Cr0:0:Y2:0:A1:A0:Y1:0:Cb0:0:Y0:0 1:1:8:2:8:2:8:2:1:1:8:2:8:2:8:2 little endian */ +#define DRM_FORMAT_Y0L0 fourcc_code('Y', '0', 'L', '0') +/* [63:0] X3:X2:Y3:0:Cr0:0:Y2:0:X1:X0:Y1:0:Cb0:0:Y0:0 1:1:8:2:8:2:8:2:1:1:8:2:8:2:8:2 little endian */ +#define DRM_FORMAT_X0L0 fourcc_code('X', '0', 'L', '0') + +/* [63:0] A3:A2:Y3:Cr0:Y2:A1:A0:Y1:Cb0:Y0 1:1:10:10:10:1:1:10:10:10 little endian */ +#define DRM_FORMAT_Y0L2 fourcc_code('Y', '0', 'L', '2') +/* [63:0] X3:X2:Y3:Cr0:Y2:X1:X0:Y1:Cb0:Y0 1:1:10:10:10:1:1:10:10:10 little endian */ +#define DRM_FORMAT_X0L2 fourcc_code('X', '0', 'L', '2') /* * 2 plane RGB + A @@ -299,6 +353,15 @@ extern "C" { #define DRM_FORMAT_MOD_SAMSUNG_64_32_TILE fourcc_mod_code(SAMSUNG, 1) /* + * Tiled, 16 (pixels) x 16 (lines) - sized macroblocks + * + * This is a simple tiled layout using tiles of 16x16 pixels in a row-major + * layout. For YCbCr formats Cb/Cr components are taken in such a way that + * they correspond to their 16x16 luma block. + */ +#define DRM_FORMAT_MOD_SAMSUNG_16_16_TILE fourcc_mod_code(SAMSUNG, 2) + +/* * Qualcomm Compressed Format * * Refers to a compressed variant of the base format that is compressed. |