[igt-dev] [PATCH i-g-t v2] lib/intel_bb: Enable custom engine support for xe

[Christoph Manszewski <christoph.manszewski@intel.com>]

Currently the 'ctx' field in batch buffer creation is interpreted as
a vm id for xe. In i915 it is interpreted as a context id. Since a xe
engine more closely resembles an i915 context, change the current
behaviour and interpret the 'ctx' fied as an xe engine id. This also
allows us to use the compute engine on xe, which currently is not
possible, due to reliance on legacy i915 flags.

v2:
 - don't destroy user provided engine in 'intel_bb_destroy' (Zbigniew)
 - destroy internally created engine before creating a new one

Signed-off-by: Christoph Manszewski <christoph.manszewski@intel.com>
Cc: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com>
---
 lib/intel_batchbuffer.c | 27 +++++++++++++++++++--------
 tests/xe/xe_intel_bb.c  |  7 +++++--
 2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/lib/intel_batchbuffer.c b/lib/intel_batchbuffer.c
index dfccc4f4..d6a44d7e 100644
--- a/lib/intel_batchbuffer.c
+++ b/lib/intel_batchbuffer.c
@@ -946,15 +946,13 @@ __intel_bb_create(int fd, uint32_t ctx, const intel_ctx_cfg_t *cfg,
 		ibb->gtt_size = 1ull << min_t(uint32_t, xe_va_bits(fd), 48);
 		end = ibb->gtt_size;
 
-		if (!ctx)
-			ctx = xe_vm_create(fd, DRM_XE_VM_CREATE_ASYNC_BIND_OPS, 0);
+		ibb->vm_id = xe_vm_create(fd, DRM_XE_VM_CREATE_ASYNC_BIND_OPS, 0);
 
 		ibb->uses_full_ppgtt = true;
 		ibb->allocator_handle =
-			intel_allocator_open_full(fd, ctx, start, end,
+			intel_allocator_open_full(fd, ibb->vm_id, start, end,
 						  allocator_type, strategy,
 						  ibb->alignment);
-		ibb->vm_id = ctx;
 		ibb->last_engine = ~0U;
 	}
 
@@ -1228,6 +1226,14 @@ static void __intel_bb_remove_intel_bufs(struct intel_bb *ibb)
 		intel_bb_remove_intel_buf(ibb, entry);
 }
 
+static void __xe_bb_destroy(struct intel_bb *ibb)
+{
+	if (ibb->engine_id)
+		xe_engine_destroy(ibb->fd, ibb->engine_id);
+	if (ibb->vm_id)
+		xe_vm_destroy(ibb->fd, ibb->vm_id);
+}
+
 /**
  * intel_bb_destroy:
  * @ibb: pointer to intel_bb
@@ -1262,8 +1268,8 @@ void intel_bb_destroy(struct intel_bb *ibb)
 		close(ibb->fence);
 	if (ibb->engine_syncobj)
 		syncobj_destroy(ibb->fd, ibb->engine_syncobj);
-	if (ibb->vm_id && !ibb->ctx)
-		xe_vm_destroy(ibb->fd, ibb->vm_id);
+	if (ibb->driver == INTEL_DRIVER_XE)
+		__xe_bb_destroy(ibb);
 
 	free(ibb->batch);
 	free(ibb->cfg);
@@ -2298,7 +2304,9 @@ __xe_bb_exec(struct intel_bb *ibb, uint64_t flags, bool sync)
 	igt_assert_eq(ibb->num_relocs, 0);
 	igt_assert_eq(ibb->xe_bound, false);
 
-	if (ibb->last_engine != engine) {
+	if (ibb->ctx) {
+		engine_id = ibb->ctx;
+	} else if (ibb->last_engine != engine) {
 		struct drm_xe_engine_class_instance inst = { };
 
 		inst.engine_instance =
@@ -2323,12 +2331,15 @@ __xe_bb_exec(struct intel_bb *ibb, uint64_t flags, bool sync)
 		}
 		igt_debug("Run on %s\n", xe_engine_class_string(inst.engine_class));
 
+		if (ibb->engine_id)
+			xe_engine_destroy(ibb->fd, ibb->engine_id);
+
 		ibb->engine_id = engine_id =
 			xe_engine_create(ibb->fd, ibb->vm_id, &inst, 0);
+		ibb->last_engine = engine;
 	} else {
 		engine_id = ibb->engine_id;
 	}
-	ibb->last_engine = engine;
 
 	map = xe_bo_map(ibb->fd, ibb->handle, ibb->size);
 	memcpy(map, ibb->batch, ibb->size);
diff --git a/tests/xe/xe_intel_bb.c b/tests/xe/xe_intel_bb.c
index 35d61608..4fcc3144 100644
--- a/tests/xe/xe_intel_bb.c
+++ b/tests/xe/xe_intel_bb.c
@@ -177,6 +177,7 @@ static void simple_bb(struct buf_ops *bops, bool new_context)
 	int xe = buf_ops_get_fd(bops);
 	struct intel_bb *ibb;
 	uint32_t ctx = 0;
+	uint32_t vm = 0;
 
 	ibb = intel_bb_create_with_allocator(xe, ctx, NULL, PAGE_SIZE,
 					     INTEL_ALLOCATOR_SIMPLE);
@@ -195,7 +196,8 @@ static void simple_bb(struct buf_ops *bops, bool new_context)
 	intel_bb_reset(ibb, true);
 
 	if (new_context) {
-		ctx = xe_vm_create(xe, DRM_XE_VM_CREATE_ASYNC_BIND_OPS, 0);
+		vm = xe_vm_create(xe, DRM_XE_VM_CREATE_ASYNC_BIND_OPS, 0);
+		ctx = xe_engine_create(xe, vm, xe_hw_engine(xe, 0), 0);
 		intel_bb_destroy(ibb);
 		ibb = intel_bb_create_with_context(xe, ctx, NULL, PAGE_SIZE);
 		intel_bb_out(ibb, MI_BATCH_BUFFER_END);
@@ -203,7 +205,8 @@ static void simple_bb(struct buf_ops *bops, bool new_context)
 		intel_bb_exec(ibb, intel_bb_offset(ibb),
 			      I915_EXEC_DEFAULT | I915_EXEC_NO_RELOC,
 			      true);
-		xe_vm_destroy(xe, ctx);
+		xe_engine_destroy(xe, ctx);
+		xe_vm_destroy(xe, vm);
 	}
 
 	intel_bb_destroy(ibb);
-- 
2.40.1