[Intel-gfx] [RFC v3 6/9] drm/framebuffer: Format modifier for Intel Gen-12 media compression

[Dhinakaran Pandiyan]

Gen-12 display can decompress surfaces compressed by the media engine, add
a new modifier as the driver needs to know the surface was compressed by
the media or render engine.

Cc: Nanley G Chery <nanley.g.chery at intel.com>
Cc: Matt Roper <matthew.d.roper at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
---
 include/uapi/drm/drm_fourcc.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
index 1f0fbf0398f6..c4a4e0fdbee5 100644
--- a/include/uapi/drm/drm_fourcc.h
+++ b/include/uapi/drm/drm_fourcc.h
@@ -421,6 +421,19 @@ extern "C" {
  */
 #define I915_FORMAT_MOD_Y_TILED_GEN12_RC_CCS fourcc_mod_code(INTEL, 6)
 
+/*
+ * Intel color control surfaces (CCS) for Gen-12 media compression
+ *
+ * The main surface is Y-tiled and at plane index 0, the CCS is linear and
+ * at index 1. A 64B CCS cache line corresponds to an area of 4x1 tiles in
+ * main surface. In other words, 4 bits in CCS map to a main surface cache
+ * line pair. The main surface pitch is required to be a multiple of four
+ * Y-tile widths. For semi-planar formats like NV12, CCS plane follows the
+ * Y and UV planes i.e., planes 0 and 2 are used for Y and UV surfaces,
+ * planes 1 and 3 for the respective CCS.
+ */
+#define I915_FORMAT_MOD_Y_TILED_GEN12_MC_CCS fourcc_mod_code(INTEL, 7)
+
 /*
  * Tiled, NV12MT, grouped in 64 (pixels) x 32 (lines) -sized macroblocks
  *
-- 
2.17.1