[PATCH 2/2] drm/xe/uapi: Expose wmtp as engine capability

[Nirmoy Das]

Add capabilities to engine struct which can be used to
expose various capabilities of each engine.

Add wmtp as engine capability which is retrieve from
GT info.

Take a field from the reserved for that purpose.

v2: Use 32 bit for capabilities(Lucas).
    Only Expose Compute engine till there is user-case
    for Render engine(Joonas).
    Don't use BIT() for uAPI (Francois)

Cc: Francois Dugast <francois.dugast at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
Cc: Lucas De Marchi <lucas.demarchi at intel.com>
Cc: Mateusz Jablonski <mateusz.jablonski at intel.com>
Reviewed-by: Matt Roper <matthew.d.roper at intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das at intel.com>
---
 drivers/gpu/drm/xe/xe_query.c |  4 ++++
 include/uapi/drm/xe_drm.h     | 12 ++++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_query.c b/drivers/gpu/drm/xe/xe_query.c
index 73ef6e4c2dc9..005f4f2da3d9 100644
--- a/drivers/gpu/drm/xe/xe_query.c
+++ b/drivers/gpu/drm/xe/xe_query.c
@@ -213,6 +213,10 @@ static int query_engines(struct xe_device *xe,
 			engines->engines[i].instance.engine_instance =
 				hwe->logical_instance;
 			engines->engines[i].instance.gt_id = gt->info.id;
+			if (gt->info.has_wmtp &&
+			    hwe->class == XE_ENGINE_CLASS_COMPUTE)
+				engines->engines[i].capabilities |=
+					DRM_XE_ENGINE_CAPABILITY_WMTP;
 
 			i++;
 		}
diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index b6fbe4988f2e..975666b6fe28 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -247,13 +247,21 @@ struct drm_xe_engine_class_instance {
 
 /**
  * struct drm_xe_engine - describe hardware engine
+ *
+ * The @capabilities can be:
+ *  - DRM_XE_ENGINE_CAPABILITY_WMTP - represents a engine's mid-thread
+ *  preemption capability.
  */
 struct drm_xe_engine {
 	/** @instance: The @drm_xe_engine_class_instance */
 	struct drm_xe_engine_class_instance instance;
-
+#define DRM_XE_ENGINE_CAPABILITY_WMTP		1
+	/** @capabilities: Capabilities of this engine. */
+	__u32 capabilities;
+	/** @pad: MBZ */
+	__u32 pad;
 	/** @reserved: Reserved */
-	__u64 reserved[3];
+	__u64 reserved[2];
 };
 
 /**
-- 
2.42.0