[PATCH] drm: drm_fourcc: Add uncompressed AFBC modifier

[Daniel Vetter]

On Wed, Apr 22, 2020 at 12:17:58PM +0100, Ben Davis wrote:
> AFBC has a mode that allows use of AFBC with an uncompressed buffer,
> we add a new modifier to support this mode.
> 
> Signed-off-by: Ben Davis <ben.davis at arm.com>
> ---
>  include/uapi/drm/drm_fourcc.h | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
> index 8bc0b31597d8..97c47baef7fc 100644
> --- a/include/uapi/drm/drm_fourcc.h
> +++ b/include/uapi/drm/drm_fourcc.h
> @@ -780,6 +780,12 @@ extern "C" {
>   */
>  #define AFBC_FORMAT_MOD_BCH     (1ULL << 11)
>  
> +/* AFBC uncompressed storage mode
> + *
> + * Indicates that the buffer is using uncompressed AFBC mode.

Since this sounds a bit baffling, might be good to spend a few more words
on what exactly this means. If it's just a fancy way of saying
linear/untiled, then this shouldn't be a modifier. If it's some kind of
specific tiling layout, then I think that should be specified (we've been
a bit more lax with the compressor magic soup, but tiled formats are
generally fully specced).
-Daniel
> + */
> +#define AFBC_FORMAT_MOD_USM	(1ULL << 12)
> +
>  /*
>   * Arm 16x16 Block U-Interleaved modifier
>   *
> -- 
> 2.24.0
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch