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

[Lucas De Marchi]

On Sat, Feb 03, 2024 at 07:05:34AM GMT, Nirmoy Das wrote:
>Add capabilities to engine struct which can be used to
>expose various capabilities of each engines.
>
>Add wmtp as engine capability which is retrieve from
>GT info.
>
>Take a field from the reserved for that purpose.
>
>Signed-off-by: Nirmoy Das <nirmoy.das at intel.com>
>---
> drivers/gpu/drm/xe/xe_query.c | 5 +++++
> include/uapi/drm/xe_drm.h     | 6 ++++--
> 2 files changed, 9 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/gpu/drm/xe/xe_query.c b/drivers/gpu/drm/xe/xe_query.c
>index 7e924faeeea0..10981b46c56f 100644
>--- a/drivers/gpu/drm/xe/xe_query.c
>+++ b/drivers/gpu/drm/xe/xe_query.c
>@@ -215,6 +215,11 @@ static int query_engines(struct xe_device *xe,
> 			engines->engines[i].instance.pad = 0;
> 			memset(engines->engines[i].reserved, 0,
> 			       sizeof(engines->engines[i].reserved));
>+			if (gt->info.has_wmtp &&
>+			    (hwe->class == XE_ENGINE_CLASS_COMPUTE ||
>+			     hwe->class == XE_ENGINE_CLASS_RENDER))
>+				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 50bbea0992d9..5dac079e64de 100644
>--- a/include/uapi/drm/xe_drm.h
>+++ b/include/uapi/drm/xe_drm.h
>@@ -247,9 +247,11 @@ struct drm_xe_engine_class_instance {
> struct drm_xe_engine {
> 	/** @instance: The @drm_xe_engine_class_instance */
> 	struct drm_xe_engine_class_instance instance;
>-
>+#define DRM_XE_ENGINE_CAPABILITY_WMTP		BIT(0)
>+	/** @capabilities: Capabilities of this engine. */
>+	__u64 capabilities;

isn't u64 a lot for this?  maybe make it u32 and add a u32 reserved?

i915 for example reserved 64b but still only uses 2 bits.

Lucas De Marchi

> 	/** @reserved: Reserved */
>-	__u64 reserved[3];
>+	__u64 reserved[2];
> };
>
> /**
>-- 
>2.42.0
>