Mesa (master): radv: add a comment from radeonsi before cp dma function.

[Dave Airlie]

Module: Mesa
Branch: master
Commit: 114d29e7fe13355f01d1ef27d50723af84b03081
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=114d29e7fe13355f01d1ef27d50723af84b03081

Author: Dave Airlie <airlied at redhat.com>
Date:   Tue Jun  6 08:43:38 2017 +1000

radv: add a comment from radeonsi before cp dma function.

This is just copied over.

Signed-off-by: Dave Airlie <airlied at redhat.com>

---

 src/amd/vulkan/si_cmd_buffer.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/amd/vulkan/si_cmd_buffer.c b/src/amd/vulkan/si_cmd_buffer.c
index 8237155bda..fdcf24e631 100644
--- a/src/amd/vulkan/si_cmd_buffer.c
+++ b/src/amd/vulkan/si_cmd_buffer.c
@@ -1001,6 +1001,10 @@ static inline unsigned cp_dma_max_byte_count(struct radv_cmd_buffer *cmd_buffer)
 	return max & ~(SI_CPDMA_ALIGNMENT - 1);
 }
 
+/* Emit a CP DMA packet to do a copy from one buffer to another, or to clear
+ * a buffer. The size must fit in bits [20:0]. If CP_DMA_CLEAR is set, src_va is a 32-bit
+ * clear value.
+ */
 static void si_emit_cp_dma(struct radv_cmd_buffer *cmd_buffer,
 			   uint64_t dst_va, uint64_t src_va,
 			   unsigned size, unsigned flags)