drm/i915/guc: GuC virtual engines

Implement GuC virtual engines. Rather simple implementation, basically
just allocate an engine, setup context enter / exit function to virtual
engine specific functions, set all other variables / functions to guc
versions, and set the engine mask to that of all the siblings.

v2: Update to work with proto-ctx
v3:
 (Daniele)
  - Drop include, add comment to intel_virtual_engine_has_heartbeat

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-2-matthew.brost@intel.com

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 43c3fb2aeb13..6a7edc839a2c 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -1796,6 +1796,20 @@ ktime_t intel_engine_get_busy_time(struct intel_engine_cs *engine, ktime_t *now)
 	return total;
 }
 
+struct intel_context *
+intel_engine_create_virtual(struct intel_engine_cs **siblings,
+			    unsigned int count)
+{
+	if (count == 0)
+		return ERR_PTR(-EINVAL);
+
+	if (count == 1)
+		return intel_context_create(siblings[0]);
+
+	GEM_BUG_ON(!siblings[0]->cops->create_virtual);
+	return siblings[0]->cops->create_virtual(siblings, count);
+}
+
 static bool match_ring(struct i915_request *rq)
 {
 	u32 ring = ENGINE_READ(rq->engine, RING_START);