[PATCH 1/3] Skip xf86HandleColormaps() at color depth 30.

[Michel Dänzer]

On 2017-12-23 07:07 AM, Mario Kleiner wrote:
> The hardware gamma luts get bypassed at color
> depth 30 anyway, so skip their setup.
> 
> Also skip drmmode_crtc_gamma_set() for a screen
> with depth 30.
> 
> Signed-off-by: Mario Kleiner <mario.kleiner.de at gmail.com>
> ---
>  src/drmmode_display.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/src/drmmode_display.c b/src/drmmode_display.c
> index 7ad3235..e5f9dbe 100644
> --- a/src/drmmode_display.c
> +++ b/src/drmmode_display.c
> @@ -1275,6 +1275,10 @@ drmmode_crtc_gamma_set(xf86CrtcPtr crtc, uint16_t *red, uint16_t *green,
>  	RADEONInfoPtr info = RADEONPTR(scrn);
>  	int i;
>  
> +	/* Hw gamma lut's are bypassed at color depth 30 */
> +	if (scrn->depth == 30)
> +		return;

It's better to set xf86CrtcFuncsRec::gamma_set = NULL in this case, to
prevent the X server from wasting work calculating gamma tables that
will never be used.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer