[PATCH v12 1/1] drm/i915: Allow user to set cache at BO creation

[Zhang, Carl]

Hi Andi & Fei,
We verified your change by UMD change:
1. implement the uAPI by
 https://github.com/intel/media-driver/commit/92c00a857433ebb34ec575e9834f473c6fcb6341
2. old kernel may not support new uAPI, so UMD try the interface firstly, if it failed, will fallback to older interfaces
https://github.com/intel/media-driver/commit/fd375cf2c5e1f6bf6b43258ff797b3134aadc9fd
3. removed some check for CPU cacheable and PAT conflict 
 https://github.com/intel/media-driver/commit/08dd244b22484770a33464c2c8ae85430e548000

after that, UMD works with your patches serious on MTL.

Acked-by: Carl Zhang <carl.zhang at intel.com>
Tested-by: Lihao Gu <lihao.gu at intel.com>


Thanks
Carl
> -----Original Message-----
> From: Andi Shyti <andi.shyti at linux.intel.com>
> Sent: Wednesday, May 31, 2023 6:49 PM
> To: Yang, Fei <fei.yang at intel.com>; Zhang, Carl <carl.zhang at intel.com>
> Cc: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org; Vivi,
> Rodrigo <rodrigo.vivi at intel.com>; andi.shyti at linux.intel.com; Chris Wilson
> <chris.p.wilson at linux.intel.com>; Roper, Matthew D
> <matthew.d.roper at intel.com>; Justen, Jordan L <jordan.l.justen at intel.com>
> Subject: Re: [PATCH v12 1/1] drm/i915: Allow user to set cache at BO creation
> 
> Hi Carl,
> 
> On Wed, May 24, 2023 at 01:02:55PM -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.
> >
> > BSpec: 45101
> >
> > Test igt at gem_create@create_ext_set_pat posted at
> > https://patchwork.freedesktop.org/series/118314/
> >
> > 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>
> 
> was it your intention to ack this patch?
> 
> Thanks,
> Andi