[RFC PATCH 5/5] drm/i915: Update execbuf IOCTL to accept N BBs

[Matthew Brost]

Add I915_EXEC_NUMBER_BB_* to drm_i915_gem_execbuffer2.flags which allows
submitting N BBs per IOCTL.

Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: Tony Ye <tony.ye at intel.com>
CC: Carl Zhang <carl.zhang at intel.com>
Cc: Daniel Vetter <daniel.vetter at intel.com>
Cc: Jason Ekstrand <jason at jlekstrand.net>
Signed-off-by: Matthew Brost <matthew.brost at intel.com>
---
 include/uapi/drm/i915_drm.h | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 0175b12b33b8..d3072cad4a7e 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -1291,7 +1291,26 @@ struct drm_i915_gem_execbuffer2 {
  */
 #define I915_EXEC_USE_EXTENSIONS	(1 << 21)
 
-#define __I915_EXEC_UNKNOWN_FLAGS (-(I915_EXEC_USE_EXTENSIONS << 1))
+/*
+ * Number of BB in execbuf2 IOCTL - 1, used to submit more than BB in a single
+ * execbuf2 IOCTL.
+ *
+ * Return -EINVAL if more than 1 BB (value 0) is specified if
+ * I915_CONTEXT_ENGINES_EXT_PARALLEL_SUBMIT hasn't been called on the gem
+ * context first. Also returns -EINVAL if gem context has been setup with
+ * I915_PARALLEL_NO_PREEMPT_MID_BATCH and the number BBs not equal to the total
+ * number hardware contexts in the gem context.
+ */
+#define I915_EXEC_NUMBER_BB_LSB		(22)
+#define I915_EXEC_NUMBER_BB_MASK	(0x3f << I915_EXEC_NUMBER_BB_LSB)
+#define I915_EXEC_NUMBER_BB_MSB		(27)
+#define i915_execbuffer2_set_number_bb(eb2, num_bb) \
+	(eb2).flags = ((eb2).flags & ~I915_EXEC_NUMBER_BB_MASK) | \
+	(((num_bb - 1) << I915_EXEC_NUMBER_BB_LSB) & I915_EXEC_NUMBER_BB_MASK)
+#define i915_execbuffer2_get_number_bb(eb2) \
+	((((eb2).flags & I915_EXEC_NUMBER_BB_MASK) >> I915_EXEC_NUMBER_BB_LSB) + 1)
+
+#define __I915_EXEC_UNKNOWN_FLAGS (-(1 << (I915_EXEC_NUMBER_BB_MSB + 1)))
 
 #define I915_EXEC_CONTEXT_ID_MASK	(0xffffffff)
 #define i915_execbuffer2_set_context_id(eb2, context) \
-- 
2.28.0