[PATCH v10 2/2] drm/i915: Allow user to set cache at BO creation

[Andi Shyti]

Hi,

On Thu, May 18, 2023 at 10:11:03PM -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 their life cycle, {set, get}_caching ioctl's
> 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.
> 
> Test igt at gem_create@create_ext_set_pat posted at
> https://patchwork.freedesktop.org/series/117695/
> 
> Tested with https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22878
> 
> Signed-off-by: Fei Yang <fei.yang at intel.com>
> 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>
> Reviewed-by: Andi Shyti <andi.shyti at linux.intel.com>
> Acked-by: Jordan Justen <jordan.l.justen at intel.com>
> Tested-by: Jordan Justen <jordan.l.justen at intel.com>

last call for comments and reviews on this patch. If nothing
comes I am going to push it tomorrow morning (Europe).

There is also a merge request from Mesa pending on this so that I
don't want to keep it hanging any longer.

Thanks,
Andi