drm/fourcc: Add modifier defininitions for AFBC 1.3

This commit adds definitions of format modifiers for version 1.3 of the
Arm Framebuffer Compression (AFBC).
Signed-off-by: Matteo Franchin <matteo.franchin@arm.com>
Signed-off-by: Ayan Kumar Halder <ayan.halder@arm.com>
Reviewed-by: Brian Starkey <brian.starkey@arm.com>
Link: https://patchwork.freedesktop.org/patch/277333/

include/uapi/drm/drm_fourcc.h

@@ -581,10 +581,18 @@ extern "C" {
  * Indicates the superblock size(s) used for the AFBC buffer. The buffer
  * size (in pixels) must be aligned to a multiple of the superblock size.
  * Four lowest significant bits(LSBs) are reserved for block size.
+ *
+ * Where one superblock size is specified, it applies to all planes of the
+ * buffer (e.g. 16x16, 32x8). When multiple superblock sizes are specified,
+ * the first applies to the Luma plane and the second applies to the Chroma
+ * plane(s). e.g. (32x8_64x4 means 32x8 Luma, with 64x4 Chroma).
+ * Multiple superblock sizes are only valid for multi-plane YCbCr formats.
  */
 #define AFBC_FORMAT_MOD_BLOCK_SIZE_MASK      0xf
 #define AFBC_FORMAT_MOD_BLOCK_SIZE_16x16     (1ULL)
 #define AFBC_FORMAT_MOD_BLOCK_SIZE_32x8      (2ULL)
+#define AFBC_FORMAT_MOD_BLOCK_SIZE_64x4      (3ULL)
+#define AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4 (4ULL)
 
 /*
  * AFBC lossless colorspace transform
@@ -644,6 +652,21 @@ extern "C" {
  */
 #define AFBC_FORMAT_MOD_SC      (1ULL <<  9)
 
+/*
+ * AFBC double-buffer
+ *
+ * Indicates that the buffer is allocated in a layout safe for front-buffer
+ * rendering.
+ */
+#define AFBC_FORMAT_MOD_DB      (1ULL << 10)
+
+/*
+ * AFBC buffer content hints
+ *
+ * Indicates that the buffer includes per-superblock content hints.
+ */
+#define AFBC_FORMAT_MOD_BCH     (1ULL << 11)
+
 #if defined(__cplusplus)
 }
 #endif