[Intel-gfx] [PATCH] i915/drm/HuC: Motivation behind having HuC

[Anusha Srivatsa]

Correct the comment in intel_huc.c that tells the motivation
behind having HuC, a dedicated firmware for media.

Cc: Lyncoln Cheng <lyncoln.cheng at intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
---
 drivers/gpu/drm/i915/intel_huc.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_huc.c b/drivers/gpu/drm/i915/intel_huc.c
index c144609..0641afe 100644
--- a/drivers/gpu/drm/i915/intel_huc.c
+++ b/drivers/gpu/drm/i915/intel_huc.c
@@ -29,9 +29,14 @@
  * DOC: HuC Firmware
  *
  * Motivation:
- * GEN9 introduces a new dedicated firmware for usage in media HEVC (High
- * Efficiency Video Coding) operations. Userspace can use the firmware
- * capabilities by adding HuC specific commands to batch buffers.
+ *
+ * HuC is designed to offload some of the media functions from
+ * the CPU to GPU. These include but are not limited to bitrate
+ * control, header parsing. For example in the case of bitrate control,
+ * driver invokes HuC in the beginning of each frame encoding pass,
+ * encode bitrate is adjusted by the calculation done by HuC. Both
+ * the HuC hardware and the encode hardcode reside in GPU. Using HuC
+ * will save unnecessary CPU-GPU synchronization
  *
  * Implementation:
  * The same firmware loader is used as the GuC. However, the actual
-- 
2.7.4