Re: [PATCH 1/3] drm/xe/oa/uapi: Expose MERT OA unit

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Mon, Dec 08, 2025 at 11:10:13AM -0800, Dixit, Ashutosh wrote:
> On Mon, 08 Dec 2025 04:48:13 -0800, Rodrigo Vivi wrote:
> >
> 
> Hi Rodrigo,
> 
> > On Fri, Dec 05, 2025 at 01:26:11PM -0800, Ashutosh Dixit wrote:
> > > A MERT OA unit is available in the SoC on some platforms. Add support
> > > for this OA unit and expose it to userspace. The MERT OA unit does not
> > > have any HW engines attached, but is otherwise similar to an OAM unit.
> > >
> > > Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
> > > Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> > > Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> > > diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> > > index 876a076fa6c0c..f520462c28643 100644
> > > --- a/include/uapi/drm/xe_drm.h
> > > +++ b/include/uapi/drm/xe_drm.h
> > > @@ -1675,6 +1675,9 @@ enum drm_xe_oa_unit_type {
> > >
> > >	/** @DRM_XE_OA_UNIT_TYPE_OAM_SAG: OAM_SAG OA unit */
> > >	DRM_XE_OA_UNIT_TYPE_OAM_SAG,
> > > +
> > > +	/** @DRM_XE_OA_UNIT_TYPE_MERT: MERT OA unit */
> > > +	DRM_XE_OA_UNIT_TYPE_MERT,
> >
> > And who&where is the usage here?
> 
> Sorry I just merged this. 

No worries, I just force pushed it out.

> I will provide the MDAPI UMD pull request for
> this when it is available. Hope this is ok.

Let's re-merge when we see the usage out there.

> 
> This functionality (memory access counters) was part of OAG OA unit but is
> now separated out into a separate OA unit on some platforms.

Yeap, but any flag or anything that changes the uapi we do in the defined
order:

1. both kernel and user space patches are sent out together and reviewed
   in paralell.
2. kernel code is acked by user-space developers (apparently not relevant
   in this case)
3. kernel patch lands first. (Here we have the user-space review already
   finished and ready to get merged)
4. user space patch lands right after.

Thanks,
Rodrigo.

> 
> Thanks.
> --
> Ashutosh