[PATCH 2/2] drm/mgag200: Use 24bit format in VRAM

[Javier Martinez Canillas]

Jocelyn Falempe <jfalempe at redhat.com> writes:

> The bandwidth between system memory and VRAM is very limited
> on G200.
> So when using a 32bit framebuffer on system memory, convert it to 24bit
> when copying the frame to the VRAM, this allows to go 33% faster.
> Converting the format on the fly is negligible, even on low end CPU.
>
> small benchmark on my Dell T310:
> 1280x1024 32bits: ~125ms to transfert a single frame.
> 1280x1024 24bits: ~95ms
>
> Signed-off-by: Jocelyn Falempe <jfalempe at redhat.com>
> ---

I assume that the alpha channel is unused on this display HW and is just
exposed to user-space to make the DRM driver more compatible ?

If so, probably has to be mentioned in the changelog but other than that:

Reviewed-by: Javier Martinez Canillas <javierm at redhat.com>

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat