[Intel-gfx] [PATCH 8/8] drm/i915: Allow user to set cache at BO creation

[Andi Shyti]

On Sun, Apr 16, 2023 at 11:25:03PM -0700, fei.yang at intel.com wrote:
> From: Fei Yang <fei.yang at intel.com>
> 
> To comply with the design that buffer objects shall have immutable
> cache setting through out its life cycle, {set, get}_caching ioctl's

/its/their/

> are no longer supported from MTL onward. With that change caching
> policy can only be set at object creation time. The current code
> applies a default (platform dependent) cache setting for all objects.
> However this is not optimal for performance tuning. The patch extends
> the existing gem_create uAPI to let user set PAT index for the object
> at creation time.
> The new extension is platform independent, so UMD's can switch to using
> this extension for older platforms as well, while {set, get}_caching are
> still supported on these legacy paltforms for compatibility reason.
> 
> Cc: Chris Wilson <chris.p.wilson at linux.intel.com>
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Cc: Andi Shyti <andi.shyti at linux.intel.com>
> Signed-off-by: Fei Yang <fei.yang at intel.com>

Reviewed-by: Andi Shyti <andi.shyti at linux.intel.com> 

Andi