[Intel-xe] [PATCH 1/1] drm/xe: Report tile count from device query api.

[Ghimiray, Himal Prasad]

> -----Original Message-----
> From: Roper, Matthew D <matthew.d.roper at intel.com>
> Sent: 07 June 2023 01:26
> To: Ghimiray, Himal Prasad <himal.prasad.ghimiray at intel.com>
> Cc: intel-xe at lists.freedesktop.org; Dugast, Francois
> <francois.dugast at intel.com>
> Subject: Re: [PATCH 1/1] drm/xe: Report tile count from device query api.
> 
> On Tue, Jun 06, 2023 at 03:19:29PM +0530, Himal Prasad Ghimiray wrote:
> > Cc: Matt Roper <matthew.d.roper at intel.com>
> > Cc: Francois Dugast <francois.dugast at intel.com>
> >
> > Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
> 
> Does userspace actually need this reported in the device query?  It seems more
> likely that they're going to need a tile-based equivalent of 'drm_xe_query_gt'
> that returns not only the tile count, but also further details about each tile.  If
> that's the case, then also adding this count as an extra field to the device-level
> query seems redundant (and the existing GT count seems like it's probably
> redundant as well).
Hi Matt,

>From userspace  perspective the requirement is to know number of tiles supported by device 
and agreed 'drm_xe_query_tile' should provide this info along with other details.
Can you please provide your inputs on what other details can be part of tile query ? 
> 
> Are there patches for any of the userspace components yet that show
> how/when they'd use this?
https://patchwork.freedesktop.org/series/118927/ exposes per tile vram addr_range via sysfs. 
While writing IGT to test this sysfs entry, I came across the requirement. IGT patches are WIP.

Just a thought, will it makes sense to expose number of tiles device supports by sysfs ? 
Something like: <device-properties>/number_tiles
IMO this info should be available to userspace even without making any code changes .
There may be other such potential candidates which can fall under device-properties.

Himal 
> 
> 
> Matt
> 
> > ---
> >  drivers/gpu/drm/xe/xe_query.c | 1 +
> >  include/uapi/drm/xe_drm.h     | 3 ++-
> >  2 files changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/xe/xe_query.c
> > b/drivers/gpu/drm/xe/xe_query.c index c4165fa3428e..54efbefd663f
> > 100644
> > --- a/drivers/gpu/drm/xe/xe_query.c
> > +++ b/drivers/gpu/drm/xe/xe_query.c
> > @@ -197,6 +197,7 @@ static int query_config(struct xe_device *xe, struct
> drm_xe_device_query *query)
> >  		hweight_long(xe->info.mem_region_mask);
> >  	config->info[XE_QUERY_CONFIG_MAX_ENGINE_PRIORITY] =
> >  		xe_engine_device_get_max_priority(xe);
> > +	config->info[XE_QUERY_CONFIG_TILE_COUNT] = xe->info.tile_count;
> >
> >  	if (copy_to_user(query_ptr, config, size)) {
> >  		kfree(config);
> > diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> > index 0ebc50beb5e5..8e552aa55037 100644
> > --- a/include/uapi/drm/xe_drm.h
> > +++ b/include/uapi/drm/xe_drm.h
> > @@ -185,7 +185,8 @@ struct drm_xe_query_config {
> >  #define XE_QUERY_CONFIG_GT_COUNT		4
> >  #define XE_QUERY_CONFIG_MEM_REGION_COUNT	5
> >  #define XE_QUERY_CONFIG_MAX_ENGINE_PRIORITY	6
> > -#define XE_QUERY_CONFIG_NUM_PARAM
> 	XE_QUERY_CONFIG_MAX_ENGINE_PRIORITY + 1
> > +#define XE_QUERY_CONFIG_TILE_COUNT		7
> > +#define XE_QUERY_CONFIG_NUM_PARAM
> 	XE_QUERY_CONFIG_TILE_COUNT + 1
> >  	__u64 info[];
> >  };
> >
> > --
> > 2.25.1
> >
> 
> --
> Matt Roper
> Graphics Software Engineer
> Linux GPU Platform Enablement
> Intel Corporation