[Intel-gfx] [PATCH] drm/fourcc: Document the Intel CCS modifiers' CC plane expected pitch

[Chery, Nanley G]

+Jordan (FYI)

I think the commit message has an extra "color" next to "CC". 
With or without that dropped,

Reviewed-by: Nanley Chery <nanley.g.chery at intel.com>

Thanks for the fix.

> -----Original Message-----
> From: Deak, Imre <imre.deak at intel.com>
> Sent: Thursday, June 23, 2022 10:50 AM
> To: dri-devel at lists.freedesktop.org
> Cc: intel-gfx at lists.freedesktop.org; Chery, Nanley G <nanley.g.chery at intel.com>
> Subject: [PATCH] drm/fourcc: Document the Intel CCS modifiers' CC plane expected pitch
> 
> The driver expects the pitch of the Intel CCS CC color planes to be
> 64 bytes aligned, adjust the modifier descriptions accordingly.
> 
> Cc: Nanley Chery <nanley.g.chery at intel.com>
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> ---
>  include/uapi/drm/drm_fourcc.h | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
> index f1972154a5940..c1b4cfda75075 100644
> --- a/include/uapi/drm/drm_fourcc.h
> +++ b/include/uapi/drm/drm_fourcc.h
> @@ -559,7 +559,7 @@ extern "C" {
>   *
>   * The main surface is Y-tiled and is at plane index 0 whereas CCS is linear
>   * and at index 1. The clear color is stored at index 2, and the pitch should
> - * be ignored. The clear color structure is 256 bits. The first 128 bits
> + * be 64 bytes aligned. The clear color structure is 256 bits. The first 128 bits
>   * represents Raw Clear Color Red, Green, Blue and Alpha color each represented
>   * by 32 bits. The raw clear color is consumed by the 3d engine and generates
>   * the converted clear color of size 64 bits. The first 32 bits store the Lower
> @@ -612,9 +612,9 @@ extern "C" {
>   * outside of the GEM object in a reserved memory area dedicated for the
>   * storage of the CCS data for all RC/RC_CC/MC compressible GEM objects. The
>   * main surface pitch is required to be a multiple of four Tile 4 widths. The
> - * clear color is stored at plane index 1 and the pitch should be ignored. The
> - * format of the 256 bits of clear color data matches the one used for the
> - * I915_FORMAT_MOD_Y_TILED_GEN12_RC_CCS_CC modifier, see its description
> + * clear color is stored at plane index 1 and the pitch should be 64 bytes
> + * aligned. The format of the 256 bits of clear color data matches the one used
> + * for the I915_FORMAT_MOD_Y_TILED_GEN12_RC_CCS_CC modifier, see its description
>   * for details.
>   */
>  #define I915_FORMAT_MOD_4_TILED_DG2_RC_CCS_CC fourcc_mod_code(INTEL, 12)
> --
> 2.30.2