[PATCH v4 19/33] drm/xe/uapi: Add DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR

[Upadhyay, Tejas]

> -----Original Message-----
> From: Intel-xe <intel-xe-bounces at lists.freedesktop.org> On Behalf Of Thomas
> Hellström
> Sent: Friday, February 7, 2025 6:35 PM
> To: Brost, Matthew <matthew.brost at intel.com>; intel-
> xe at lists.freedesktop.org; dri-devel at lists.freedesktop.org
> Cc: Ghimiray, Himal Prasad <himal.prasad.ghimiray at intel.com>;
> apopple at nvidia.com; airlied at gmail.com; simona.vetter at ffwll.ch;
> felix.kuehling at amd.com; dakr at kernel.org
> Subject: Re: [PATCH v4 19/33] drm/xe/uapi: Add
> DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR
> 
> On Wed, 2025-01-29 at 11:51 -0800, Matthew Brost wrote:
> > Add the DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR device
> query
> > flag, which indicates whether the device supports CPU address
> > mirroring.
> > The
> > intent is for UMDs to use this query to determine if a VM can be set
> > up with CPU address mirroring. This flag is implemented by checking if
> > the device supports GPU faults.
> >
> > Signed-off-by: Matthew Brost <matthew.brost at intel.com>
> Reviewed-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> 
> > ---
> >  drivers/gpu/drm/xe/xe_query.c | 5 ++++-
> >  include/uapi/drm/xe_drm.h     | 3 +++
> >  2 files changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/xe/xe_query.c
> > b/drivers/gpu/drm/xe/xe_query.c index c059639613f7..40f56eaf98fa
> > 100644
> > --- a/drivers/gpu/drm/xe/xe_query.c
> > +++ b/drivers/gpu/drm/xe/xe_query.c
> > @@ -333,8 +333,11 @@ static int query_config(struct xe_device *xe,
> > struct drm_xe_device_query *query)
> >  	config->info[DRM_XE_QUERY_CONFIG_REV_AND_DEVICE_ID] =
> >  		xe->info.devid | (xe->info.revid << 16);
> >  	if (xe_device_get_root_tile(xe)->mem.vram.usable_size)
> > -		config->info[DRM_XE_QUERY_CONFIG_FLAGS] =
> > +		config->info[DRM_XE_QUERY_CONFIG_FLAGS] |=
> >  			DRM_XE_QUERY_CONFIG_FLAG_HAS_VRAM;
> > +	if (xe->info.has_usm)
> > +		config->info[DRM_XE_QUERY_CONFIG_FLAGS] |=
> > +
> 	DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR
> > ;
> >  	config->info[DRM_XE_QUERY_CONFIG_MIN_ALIGNMENT] =
> >  		xe->info.vram_flags & XE_VRAM_FLAGS_NEED64K ? SZ_64K
> > : SZ_4K;
> >  	config->info[DRM_XE_QUERY_CONFIG_VA_BITS] = xe-
> > >info.va_bits;
> > diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> > index b86dc1b4c2fe..37e54ca6ffe9 100644
> > --- a/include/uapi/drm/xe_drm.h
> > +++ b/include/uapi/drm/xe_drm.h
> > @@ -393,6 +393,8 @@ struct drm_xe_query_mem_regions {
> >   *
> >   *    - %DRM_XE_QUERY_CONFIG_FLAG_HAS_VRAM - Flag is set if the
> > device
> >   *      has usable VRAM
> > + *    - %DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR - Flag is
> set
> > if the
> > + *      device has CPU address mirroring support
> >   *  - %DRM_XE_QUERY_CONFIG_MIN_ALIGNMENT - Minimal memory
> alignment
> >   *    required by this device, typically SZ_4K or SZ_64K
> >   *  - %DRM_XE_QUERY_CONFIG_VA_BITS - Maximum bits of a virtual
> > address @@ -409,6 +411,7 @@ struct drm_xe_query_config {
> >  #define DRM_XE_QUERY_CONFIG_REV_AND_DEVICE_ID	0
> >  #define DRM_XE_QUERY_CONFIG_FLAGS			1
> >  	#define DRM_XE_QUERY_CONFIG_FLAG_HAS_VRAM	(1 << 0)
> > +	#define DRM_XE_QUERY_CONFIG_FLAG_HAS_CPU_ADDR_MIRROR
> 	(1
> > << 1)

I don’t know how we handle this, but https://patchwork.freedesktop.org/patch/635834/ is getting merged soon, will conflict with (1 << 1). If its like whoever merges first then it should be ok to keep it this way and you can add my r-o-b. Or else if we should adjust now!

Anyways,
Reviewed-by: Tejas Upadhyay <tejas.upadhyay at intel.com>

> >  #define DRM_XE_QUERY_CONFIG_MIN_ALIGNMENT		2
> >  #define DRM_XE_QUERY_CONFIG_VA_BITS			3
> >  #define DRM_XE_QUERY_CONFIG_MAX_EXEC_QUEUE_PRIORITY	4