media: verisilicon: Add film grain feature to AV1 driver

Film grain feature add "old style" grain noise on decoded streams.
Grain noise is applied after decoding by the postprocessor.
The level of grain is based on gaussian sequence.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Author: Benjamin Gaignard

drivers/media/platform/verisilicon/Makefile

@@ -19,6 +19,7 @@ hantro-vpu-y += \
 		rockchip_vpu2_hw_mpeg2_dec.o \
 		rockchip_vpu2_hw_vp8_dec.o \
 		rockchip_vpu981_hw_av1_dec.o \
+		rockchip_av1_filmgrain.o \
 		rockchip_av1_entropymode.o \
 		hantro_jpeg.o \
 		hantro_h264.o \

drivers/media/platform/verisilicon/hantro_hw.h

@@ -16,6 +16,7 @@
 #include <media/videobuf2-core.h>
 
 #include "rockchip_av1_entropymode.h"
+#include "rockchip_av1_filmgrain.h"
 
 #define DEC_8190_ALIGN_MASK	0x07U
 
@@ -288,6 +289,7 @@ struct hantro_av1_frame_ref {
  * @global_model:	global model buffer
  * @tile_info:		tile info buffer
  * @segment:		segmentation info buffer
+ * @film_grain:		film grain buffer
  * @prob_tbl:		probability table
  * @prob_tbl_out:	probability table output
  * @tile_buf:		tile buffer
@@ -312,6 +314,7 @@ struct hantro_av1_dec_hw_ctx {
 	struct hantro_aux_buf global_model;
 	struct hantro_aux_buf tile_info;
 	struct hantro_aux_buf segment;
+	struct hantro_aux_buf film_grain;
 	struct hantro_aux_buf prob_tbl;
 	struct hantro_aux_buf prob_tbl_out;
 	struct hantro_aux_buf tile_buf;