drm/amdgpu: add UAPI to create secure commands (v3)

Add a flag to the command submission IOCTL
structure which when present indicates that this
command submission should be treated as
secure. The kernel driver uses this flag to
determine whether the engine should be
transitioned to secure or unsecure, or the work
can be submitted to a secure queue depending on
the IP.

v3: the flag is now at command submission IOCTL
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

include/uapi/drm/amdgpu_drm.h

@@ -205,6 +205,9 @@ union drm_amdgpu_bo_list {
 #define AMDGPU_CTX_OP_QUERY_STATE	3
 #define AMDGPU_CTX_OP_QUERY_STATE2	4
 
+/* Flag the command submission as secure */
+#define AMDGPU_CS_FLAGS_SECURE          (1 << 0)
+
 /* GPU reset status */
 #define AMDGPU_CTX_NO_RESET		0
 /* this the context caused it */
@@ -564,7 +567,7 @@ struct drm_amdgpu_cs_in {
 	/**  Handle of resource list associated with CS */
 	__u32		bo_list_handle;
 	__u32		num_chunks;
-	__u32		_pad;
+	__u32		flags;
 	/** this points to __u64 * which point to cs chunks */
 	__u64		chunks;
 };