Re: [PATCH v4 2/2] media: cedrus: Add H264 decoding support

From: Jernej Åkrabec
Date: Wed Feb 20 2019 - 12:51:04 EST


Hi!

I really wanted to do another review on previous series but got distracted by
analyzing one particulary troublesome H264 sample. It still doesn't work
correctly, so I would ask you if you can test it with your stack (it might be
userspace issue):

http://jernej.libreelec.tv/videos/problematic/test.mkv

Please take a look at my comments below.

Dne sreda, 20. februar 2019 ob 15:17:34 CET je Maxime Ripard napisal(a):
> Introduce some basic H264 decoding support in cedrus. So far, only the
> baseline profile videos have been tested, and some more advanced features
> used in higher profiles are not even implemented.

What is not yet implemented? Multi slice frame decoding, interlaced frames and
decoding frames with width > 2048. Anything else?

>
> Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx>
> ---
> drivers/staging/media/sunxi/cedrus/Makefile | 3 +-
> drivers/staging/media/sunxi/cedrus/cedrus.c | 30 +-
> drivers/staging/media/sunxi/cedrus/cedrus.h | 38 +-
> drivers/staging/media/sunxi/cedrus/cedrus_dec.c | 13 +-
> drivers/staging/media/sunxi/cedrus/cedrus_h264.c | 584 +++++++++++++++-
> drivers/staging/media/sunxi/cedrus/cedrus_hw.c | 4 +-
> drivers/staging/media/sunxi/cedrus/cedrus_regs.h | 91 ++-
> drivers/staging/media/sunxi/cedrus/cedrus_video.c | 9 +-
> 8 files changed, 770 insertions(+), 2 deletions(-)
> create mode 100644 drivers/staging/media/sunxi/cedrus/cedrus_h264.c
>
> diff --git a/drivers/staging/media/sunxi/cedrus/Makefile
> b/drivers/staging/media/sunxi/cedrus/Makefile index
> e9dc68b7bcb6..aaf141fc58b6 100644
> --- a/drivers/staging/media/sunxi/cedrus/Makefile
> +++ b/drivers/staging/media/sunxi/cedrus/Makefile
> @@ -1,3 +1,4 @@
> obj-$(CONFIG_VIDEO_SUNXI_CEDRUS) += sunxi-cedrus.o
>
> -sunxi-cedrus-y = cedrus.o cedrus_video.o cedrus_hw.o cedrus_dec.o
> cedrus_mpeg2.o +sunxi-cedrus-y = cedrus.o cedrus_video.o cedrus_hw.o
> cedrus_dec.o \ + cedrus_mpeg2.o cedrus_h264.o
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.c
> b/drivers/staging/media/sunxi/cedrus/cedrus.c index
> ff11cbeba205..c1607142d998 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus.c
> @@ -40,6 +40,35 @@ static const struct cedrus_control cedrus_controls[] = {
> .codec = CEDRUS_CODEC_MPEG2,
> .required = false,
> },
> + {
> + .id =
V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS,
> + .elem_size = sizeof(struct
v4l2_ctrl_h264_decode_param),
> + .codec = CEDRUS_CODEC_H264,
> + .required = true,
> + },
> + {
> + .id =
V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS,
> + .elem_size = sizeof(struct v4l2_ctrl_h264_slice_param),
> + .codec = CEDRUS_CODEC_H264,
> + .required = true,
> + },
> + {
> + .id = V4L2_CID_MPEG_VIDEO_H264_SPS,
> + .elem_size = sizeof(struct v4l2_ctrl_h264_sps),
> + .codec = CEDRUS_CODEC_H264,
> + .required = true,
> + },
> + {
> + .id = V4L2_CID_MPEG_VIDEO_H264_PPS,
> + .elem_size = sizeof(struct v4l2_ctrl_h264_pps),
> + .codec = CEDRUS_CODEC_H264,
> + .required = true,
> + },
> + {
> + .id =
V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX,
> + .elem_size = sizeof(struct
v4l2_ctrl_h264_scaling_matrix),
> + .codec = CEDRUS_CODEC_H264,
> + },
> };
>
> #define CEDRUS_CONTROLS_COUNT ARRAY_SIZE(cedrus_controls)
> @@ -278,6 +307,7 @@ static int cedrus_probe(struct platform_device *pdev)
> }
>
> dev->dec_ops[CEDRUS_CODEC_MPEG2] = &cedrus_dec_ops_mpeg2;
> + dev->dec_ops[CEDRUS_CODEC_H264] = &cedrus_dec_ops_h264;
>
> mutex_init(&dev->dev_mutex);
>
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.h
> b/drivers/staging/media/sunxi/cedrus/cedrus.h index
> 4aedd24a9848..8c64f9a27e9d 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus.h
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus.h
> @@ -30,7 +30,7 @@
>
> enum cedrus_codec {
> CEDRUS_CODEC_MPEG2,
> -
> + CEDRUS_CODEC_H264,
> CEDRUS_CODEC_LAST,
> };
>
> @@ -40,6 +40,12 @@ enum cedrus_irq_status {
> CEDRUS_IRQ_OK,
> };
>
> +enum cedrus_h264_pic_type {
> + CEDRUS_H264_PIC_TYPE_FRAME = 0,
> + CEDRUS_H264_PIC_TYPE_FIELD,
> + CEDRUS_H264_PIC_TYPE_MBAFF,
> +};
> +
> struct cedrus_control {
> u32 id;
> u32 elem_size;
> @@ -47,6 +53,14 @@ struct cedrus_control {
> unsigned char required:1;
> };
>
> +struct cedrus_h264_run {
> + const struct v4l2_ctrl_h264_decode_param *decode_param;
> + const struct v4l2_ctrl_h264_pps *pps;
> + const struct v4l2_ctrl_h264_scaling_matrix *scaling_matrix;
> + const struct v4l2_ctrl_h264_slice_param *slice_param;
> + const struct v4l2_ctrl_h264_sps *sps;
> +};
> +
> struct cedrus_mpeg2_run {
> const struct v4l2_ctrl_mpeg2_slice_params *slice_params;
> const struct v4l2_ctrl_mpeg2_quantization *quantization;
> @@ -57,12 +71,20 @@ struct cedrus_run {
> struct vb2_v4l2_buffer *dst;
>
> union {
> + struct cedrus_h264_run h264;
> struct cedrus_mpeg2_run mpeg2;
> };
> };
>
> struct cedrus_buffer {
> struct v4l2_m2m_buffer m2m_buf;
> +
> + union {
> + struct {
> + unsigned int position;
> + enum cedrus_h264_pic_type pic_type;
> + } h264;
> + } codec;
> };
>
> struct cedrus_ctx {
> @@ -77,6 +99,19 @@ struct cedrus_ctx {
> struct v4l2_ctrl **ctrls;
>
> struct vb2_buffer *dst_bufs[VIDEO_MAX_FRAME];
> +
> + union {
> + struct {
> + void *mv_col_buf;
> + dma_addr_t mv_col_buf_dma;
> + ssize_t mv_col_buf_field_size;
> + ssize_t mv_col_buf_size;
> + void *pic_info_buf;
> + dma_addr_t pic_info_buf_dma;
> + void *neighbor_info_buf;
> + dma_addr_t neighbor_info_buf_dma;
> + } h264;
> + } codec;
> };
>
> struct cedrus_dec_ops {
> @@ -118,6 +153,7 @@ struct cedrus_dev {
> };
>
> extern struct cedrus_dec_ops cedrus_dec_ops_mpeg2;
> +extern struct cedrus_dec_ops cedrus_dec_ops_h264;
>
> static inline void cedrus_write(struct cedrus_dev *dev, u32 reg, u32 val)
> {
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
> b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c index
> 4d6d602cdde6..a290ae1b8f4d 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
> @@ -46,6 +46,19 @@ void cedrus_device_run(void *priv)
> V4L2_CID_MPEG_VIDEO_MPEG2_QUANTIZATION);
> break;
>
> + case V4L2_PIX_FMT_H264_SLICE:
> + run.h264.decode_param = cedrus_find_control_data(ctx,
> + V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS);
> + run.h264.pps = cedrus_find_control_data(ctx,
> + V4L2_CID_MPEG_VIDEO_H264_PPS);
> + run.h264.scaling_matrix = cedrus_find_control_data(ctx,
> + V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX);
> + run.h264.slice_param = cedrus_find_control_data(ctx,
> + V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS);
> + run.h264.sps = cedrus_find_control_data(ctx,
> + V4L2_CID_MPEG_VIDEO_H264_SPS);
> + break;
> +
> default:
> break;
> }
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_h264.c
> b/drivers/staging/media/sunxi/cedrus/cedrus_h264.c new file mode 100644
> index 000000000000..51e5f57120a2
> --- /dev/null
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_h264.c
> @@ -0,0 +1,584 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Cedrus VPU driver
> + *
> + * Copyright (c) 2013 Jens Kuske <jenskuske@xxxxxxxxx>
> + * Copyright (c) 2018 Bootlin
> + */
> +
> +#include <linux/types.h>
> +
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include "cedrus.h"
> +#include "cedrus_hw.h"
> +#include "cedrus_regs.h"
> +
> +enum cedrus_h264_sram_off {
> + CEDRUS_SRAM_H264_PRED_WEIGHT_TABLE = 0x000,
> + CEDRUS_SRAM_H264_FRAMEBUFFER_LIST = 0x100,
> + CEDRUS_SRAM_H264_REF_LIST_0 = 0x190,
> + CEDRUS_SRAM_H264_REF_LIST_1 = 0x199,
> + CEDRUS_SRAM_H264_SCALING_LIST_8x8_0 = 0x200,
> + CEDRUS_SRAM_H264_SCALING_LIST_8x8_1 = 0x210,
> + CEDRUS_SRAM_H264_SCALING_LIST_4x4 = 0x220,
> +};
> +
> +struct cedrus_h264_sram_ref_pic {
> + __le32 top_field_order_cnt;
> + __le32 bottom_field_order_cnt;
> + __le32 frame_info;
> + __le32 luma_ptr;
> + __le32 chroma_ptr;
> + __le32 mv_col_top_ptr;
> + __le32 mv_col_bot_ptr;
> + __le32 reserved;
> +} __packed;
> +
> +#define CEDRUS_H264_FRAME_NUM 18
> +
> +#define CEDRUS_NEIGHBOR_INFO_BUF_SIZE (16 * SZ_1K)
> +#define CEDRUS_PIC_INFO_BUF_SIZE (128 * SZ_1K)
> +
> +static void cedrus_h264_write_sram(struct cedrus_dev *dev,
> + enum cedrus_h264_sram_off off,
> + const void *data, size_t len)
> +{
> + const u32 *buffer = data;
> + size_t count = DIV_ROUND_UP(len, 4);
> +
> + cedrus_write(dev, VE_AVC_SRAM_PORT_OFFSET, off << 2);
> +
> + do {
> + cedrus_write(dev, VE_AVC_SRAM_PORT_DATA, *buffer++);
> + } while (--count);

Above loop will still write one word for count = 0. I propose following:

while (count--)
cedrus_write(dev, VE_AVC_SRAM_PORT_DATA, *buffer++);

> +}
> +
> +static dma_addr_t cedrus_h264_mv_col_buf_addr(struct cedrus_ctx *ctx,
> + unsigned int
position,
> + unsigned int
field)
> +{
> + dma_addr_t addr = ctx->codec.h264.mv_col_buf_dma;
> +
> + /* Adjust for the position */
> + addr += position * ctx->codec.h264.mv_col_buf_field_size * 2;
> +
> + /* Adjust for the field */
> + addr += field * ctx->codec.h264.mv_col_buf_field_size;
> +
> + return addr;
> +}
> +
> +static void cedrus_fill_ref_pic(struct cedrus_ctx *ctx,
> + struct cedrus_buffer *buf,
> + unsigned int top_field_order_cnt,
> + unsigned int
bottom_field_order_cnt,
> + struct cedrus_h264_sram_ref_pic
*pic)
> +{
> + struct vb2_buffer *vbuf = &buf->m2m_buf.vb.vb2_buf;
> + unsigned int position = buf->codec.h264.position;
> +
> + pic->top_field_order_cnt = top_field_order_cnt;
> + pic->bottom_field_order_cnt = bottom_field_order_cnt;
> + pic->frame_info = buf->codec.h264.pic_type << 8;
> +
> + pic->luma_ptr = cedrus_buf_addr(vbuf, &ctx->dst_fmt, 0);
> + pic->chroma_ptr = cedrus_buf_addr(vbuf, &ctx->dst_fmt, 1);
> + pic->mv_col_top_ptr = cedrus_h264_mv_col_buf_addr(ctx, position,
0);
> + pic->mv_col_bot_ptr = cedrus_h264_mv_col_buf_addr(ctx, position,
1);
> +}
> +
> +static void cedrus_write_frame_list(struct cedrus_ctx *ctx,
> + struct cedrus_run *run)
> +{
> + struct cedrus_h264_sram_ref_pic pic_list[CEDRUS_H264_FRAME_NUM];
> + const struct v4l2_ctrl_h264_decode_param *dec_param =
> run->h264.decode_param; + const struct v4l2_ctrl_h264_slice_param
*slice =
> run->h264.slice_param; + const struct v4l2_ctrl_h264_sps *sps =
> run->h264.sps;
> + const struct vb2_buffer *dst_buf = &run->dst->vb2_buf;
> + struct vb2_queue *cap_q = &ctx->fh.m2m_ctx->cap_q_ctx.q;
> + struct cedrus_buffer *output_buf;
> + struct cedrus_dev *dev = ctx->dev;
> + unsigned long used_dpbs = 0;
> + unsigned int position;
> + unsigned int output = 0;
> + unsigned int i;
> +
> + memset(pic_list, 0, sizeof(pic_list));
> +
> + for (i = 0; i < ARRAY_SIZE(dec_param->dpb); i++) {
> + const struct v4l2_h264_dpb_entry *dpb = &dec_param-
>dpb[i];
> + struct cedrus_buffer *cedrus_buf;
> + int buf_idx;
> +
> + if (!(dpb->flags & V4L2_H264_DPB_ENTRY_FLAG_VALID))
> + continue;
> +
> + buf_idx = vb2_find_timestamp(cap_q, dpb->timestamp, 0);
> + if (buf_idx < 0)
> + continue;
> +
> + cedrus_buf = vb2_to_cedrus_buffer(ctx-
>dst_bufs[buf_idx]);
> + position = cedrus_buf->codec.h264.position;
> + used_dpbs |= BIT(position);
> +
> + if (!(dpb->flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE))
> + continue;
> +
> + cedrus_fill_ref_pic(ctx, cedrus_buf,
> + dpb->top_field_order_cnt,
> + dpb->bottom_field_order_cnt,
> + &pic_list[position]);
> +
> + output = max(position, output);
> + }
> +
> + position = find_next_zero_bit(&used_dpbs, CEDRUS_H264_FRAME_NUM,
> + output);
> + if (position >= CEDRUS_H264_FRAME_NUM)
> + position = find_first_zero_bit(&used_dpbs,
CEDRUS_H264_FRAME_NUM);

I guess you didn't try any interlaced videos? Sometimes it happens that buffer
is reference and output at the same time. In such cases, above code would make
two entries, which doesn't work based on Kwiboo's and my experiments.

I guess decoding interlaced videos is out of scope at this time?

> +
> + output_buf = vb2_to_cedrus_buffer(&run->dst->vb2_buf);
> + output_buf->codec.h264.position = position;
> +
> + if (slice->flags & V4L2_H264_SLICE_FLAG_FIELD_PIC)
> + output_buf->codec.h264.pic_type =
CEDRUS_H264_PIC_TYPE_FIELD;
> + else if (sps->flags & V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD)
> + output_buf->codec.h264.pic_type =
CEDRUS_H264_PIC_TYPE_MBAFF;
> + else
> + output_buf->codec.h264.pic_type =
CEDRUS_H264_PIC_TYPE_FRAME;
> +
> + cedrus_fill_ref_pic(ctx, output_buf,
> + dec_param->top_field_order_cnt,
> + dec_param->bottom_field_order_cnt,
> + &pic_list[position]);
> +
> + cedrus_h264_write_sram(dev, CEDRUS_SRAM_H264_FRAMEBUFFER_LIST,
> + pic_list, sizeof(pic_list));
> +
> + cedrus_write(dev, VE_H264_OUTPUT_FRAME_IDX, position);
> +}
> +
> +#define CEDRUS_MAX_REF_IDX 32
> +
> +static void _cedrus_write_ref_list(struct cedrus_ctx *ctx,
> + struct cedrus_run *run,
> + const u8 *ref_list, u8 num_ref,
> + enum cedrus_h264_sram_off sram)
> +{
> + const struct v4l2_ctrl_h264_decode_param *decode = run-
>h264.decode_param;
> + struct vb2_queue *cap_q = &ctx->fh.m2m_ctx->cap_q_ctx.q;
> + const struct vb2_buffer *dst_buf = &run->dst->vb2_buf;
> + struct cedrus_dev *dev = ctx->dev;
> + u8 sram_array[CEDRUS_MAX_REF_IDX];
> + unsigned int i;
> + size_t size;
> +
> + memset(sram_array, 0, sizeof(sram_array));
> +
> + for (i = 0; i < num_ref; i++) {
> + const struct v4l2_h264_dpb_entry *dpb;
> + const struct cedrus_buffer *cedrus_buf;
> + const struct vb2_v4l2_buffer *ref_buf;
> + unsigned int position;
> + int buf_idx;
> + u8 dpb_idx;
> +
> + dpb_idx = ref_list[i];
> + dpb = &decode->dpb[dpb_idx];
> +
> + if (!(dpb->flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE))
> + continue;
> +
> + buf_idx = vb2_find_timestamp(cap_q, dpb->timestamp, 0);
> + if (buf_idx < 0)
> + continue;
> +
> + ref_buf = to_vb2_v4l2_buffer(ctx->dst_bufs[buf_idx]);
> + cedrus_buf = vb2_v4l2_to_cedrus_buffer(ref_buf);
> + position = cedrus_buf->codec.h264.position;
> +
> + sram_array[i] |= position << 1;
> + if (ref_buf->field == V4L2_FIELD_BOTTOM)

I'm still not convinced that checking buffer field is appropriate solution here.
IMO this bit defines top or bottom reference and same buffer could be used for
both.

But I guess this belongs for follow up patch which will fix decoding interlaced
videos.

> + sram_array[i] |= BIT(0);
> + }
> +
> + size = min_t(size_t, ALIGN(num_ref, 4), sizeof(sram_array));
> + cedrus_h264_write_sram(dev, sram, &sram_array, size);
> +}
> +
> +static void cedrus_write_ref_list0(struct cedrus_ctx *ctx,
> + struct cedrus_run *run)
> +{
> + const struct v4l2_ctrl_h264_slice_param *slice = run-
>h264.slice_param;
> +
> + _cedrus_write_ref_list(ctx, run,
> + slice->ref_pic_list0,
> + slice->num_ref_idx_l0_active_minus1 +
1,
> + CEDRUS_SRAM_H264_REF_LIST_0);
> +}
> +
> +static void cedrus_write_ref_list1(struct cedrus_ctx *ctx,
> + struct cedrus_run *run)
> +{
> + const struct v4l2_ctrl_h264_slice_param *slice = run-
>h264.slice_param;
> +
> + _cedrus_write_ref_list(ctx, run,
> + slice->ref_pic_list1,
> + slice->num_ref_idx_l1_active_minus1 +
1,
> + CEDRUS_SRAM_H264_REF_LIST_1);
> +}
> +
> +static void cedrus_write_scaling_lists(struct cedrus_ctx *ctx,
> + struct cedrus_run *run)
> +{
> + const struct v4l2_ctrl_h264_scaling_matrix *scaling =
> + run->h264.scaling_matrix;
> + struct cedrus_dev *dev = ctx->dev;
> +
> + if (!scaling)
> + return;
> +
> + cedrus_h264_write_sram(dev, CEDRUS_SRAM_H264_SCALING_LIST_8x8_0,
> + scaling->scaling_list_8x8[0],
> + sizeof(scaling->scaling_list_8x8[0]));
> +
> + cedrus_h264_write_sram(dev, CEDRUS_SRAM_H264_SCALING_LIST_8x8_1,
> + scaling->scaling_list_8x8[1],
> + sizeof(scaling->scaling_list_8x8[1]));

Index above should be 3. IIRC 1 and 3 are used by 4:2:0 chroma subsampling,
but currently I'm unable to find reference to that in standard.

> +
> + cedrus_h264_write_sram(dev, CEDRUS_SRAM_H264_SCALING_LIST_4x4,
> + scaling->scaling_list_4x4,
> + sizeof(scaling->scaling_list_4x4));
> +}
> +
> +static void cedrus_write_pred_weight_table(struct cedrus_ctx *ctx,
> + struct cedrus_run
*run)
> +{
> + const struct v4l2_ctrl_h264_slice_param *slice =
> + run->h264.slice_param;
> + const struct v4l2_h264_pred_weight_table *pred_weight =
> + &slice->pred_weight_table;
> + struct cedrus_dev *dev = ctx->dev;
> + int i, j, k;
> +
> + cedrus_write(dev, VE_H264_SHS_WP,
> + ((pred_weight->chroma_log2_weight_denom & 0xf) <<
4) |
> + ((pred_weight->luma_log2_weight_denom & 0xf) <<
0));

Denominators are only in range of 0-7, so mask should be 0x7. CedarX code also
specify those two fields 3 bits wide.

> +
> + cedrus_write(dev, VE_AVC_SRAM_PORT_OFFSET,
> + CEDRUS_SRAM_H264_PRED_WEIGHT_TABLE << 2);
> +
> + for (i = 0; i < ARRAY_SIZE(pred_weight->weight_factors); i++) {
> + const struct v4l2_h264_weight_factors *factors =
> + &pred_weight->weight_factors[i];
> +
> + for (j = 0; j < ARRAY_SIZE(factors->luma_weight); j++) {
> + u32 val;
> +
> + val = ((factors->luma_offset[j] & 0x1ff) << 16)
|
> + (factors->luma_weight[j] & 0x1ff);
> + cedrus_write(dev, VE_AVC_SRAM_PORT_DATA,
val);

You should cast offset varible to wider type. Currently some videos which use
prediction weight table don't work for me, unless offset is casted to u32 first.
Shifting 8 bit variable for 16 places gives you 0 every time.

Luma offset and weight are defined as s8, so having wider mask doesn't really
make sense. However, I think weight should be s16 anyway, because standard
says that it's value could be 2^denominator for default value or in range
-128..127. Worst case would be 2^7 = 128 and -128. To cover both values you
need at least 9 bits.

I guess there is a way to detect when default values need to be written (if at
all) and that can be handled separately. But I don't see any reason why bigger
type can't be used for just in case. Offset being s8 is fine and you can drop
mask for it.

Everything applies for chroma below too.

> + }
> +
> + for (j = 0; j < ARRAY_SIZE(factors->chroma_weight); j++)
{
> + for (k = 0; k < ARRAY_SIZE(factors-
>chroma_weight[0]); k++) {
> + u32 val;
> +
> + val = ((factors->chroma_offset[j]
[k] & 0x1ff) << 16) |
> + (factors-
>chroma_weight[j][k] & 0x1ff);
> + cedrus_write(dev,
VE_AVC_SRAM_PORT_DATA, val);
> + }
> + }
> + }
> +}
> +
> +static void cedrus_set_params(struct cedrus_ctx *ctx,
> + struct cedrus_run *run)
> +{
> + const struct v4l2_ctrl_h264_scaling_matrix *scaling =
> run->h264.scaling_matrix; + const struct v4l2_ctrl_h264_decode_param
> *decode = run->h264.decode_param; + const struct
v4l2_ctrl_h264_slice_param
> *slice = run->h264.slice_param; + const struct v4l2_ctrl_h264_pps *pps =
> run->h264.pps;
> + const struct v4l2_ctrl_h264_sps *sps = run->h264.sps;
> + struct vb2_buffer *src_buf = &run->src->vb2_buf;
> + struct cedrus_dev *dev = ctx->dev;
> + dma_addr_t src_buf_addr;
> + u32 offset = slice->header_bit_size;
> + u32 len = (slice->size * 8) - offset;
> + u32 reg;
> +
> + cedrus_write(dev, VE_H264_VLD_LEN, len);
> + cedrus_write(dev, VE_H264_VLD_OFFSET, offset);
> +
> + src_buf_addr = vb2_dma_contig_plane_dma_addr(src_buf, 0);
> + cedrus_write(dev, VE_H264_VLD_END,
> + src_buf_addr + vb2_get_plane_payload(src_buf, 0));
> + cedrus_write(dev, VE_H264_VLD_ADDR,
> + VE_H264_VLD_ADDR_VAL(src_buf_addr) |
> + VE_H264_VLD_ADDR_FIRST | VE_H264_VLD_ADDR_VALID |
> + VE_H264_VLD_ADDR_LAST);
> +
> + /*
> + * FIXME: Since the bitstream parsing is done in software, and
> + * in userspace, this shouldn't be needed anymore. But it
> + * turns out that removing it breaks the decoding process,
> + * without any clear indication why.
> + */
> + cedrus_write(dev, VE_H264_TRIGGER_TYPE,
> + VE_H264_TRIGGER_TYPE_INIT_SWDEC);
> +
> + if (((pps->flags & V4L2_H264_PPS_FLAG_WEIGHTED_PRED) &&
> + (slice->slice_type == V4L2_H264_SLICE_TYPE_P ||
> + slice->slice_type == V4L2_H264_SLICE_TYPE_SP)) ||
> + (pps->weighted_bipred_idc == 1 &&
> + slice->slice_type == V4L2_H264_SLICE_TYPE_B))
> + cedrus_write_pred_weight_table(ctx, run);
> +
> + if ((slice->slice_type == V4L2_H264_SLICE_TYPE_P) ||
> + (slice->slice_type == V4L2_H264_SLICE_TYPE_SP) ||
> + (slice->slice_type == V4L2_H264_SLICE_TYPE_B))
> + cedrus_write_ref_list0(ctx, run);
> +
> + if (slice->slice_type == V4L2_H264_SLICE_TYPE_B)
> + cedrus_write_ref_list1(ctx, run);
> +
> + // picture parameters
> + reg = 0;
> + /*
> + * FIXME: the kernel headers are allowing the default value to
> + * be passed, but the libva doesn't give us that.
> + */
> + reg |= (slice->num_ref_idx_l0_active_minus1 & 0x1f) << 10;
> + reg |= (slice->num_ref_idx_l1_active_minus1 & 0x1f) << 5;
> + reg |= (pps->weighted_bipred_idc & 0x3) << 2;
> + if (pps->flags & V4L2_H264_PPS_FLAG_ENTROPY_CODING_MODE)
> + reg |= VE_H264_PPS_ENTROPY_CODING_MODE;
> + if (pps->flags & V4L2_H264_PPS_FLAG_WEIGHTED_PRED)
> + reg |= VE_H264_PPS_WEIGHTED_PRED;
> + if (pps->flags & V4L2_H264_PPS_FLAG_CONSTRAINED_INTRA_PRED)
> + reg |= VE_H264_PPS_CONSTRAINED_INTRA_PRED;
> + if (pps->flags & V4L2_H264_PPS_FLAG_TRANSFORM_8X8_MODE)
> + reg |= VE_H264_PPS_TRANSFORM_8X8_MODE;
> + cedrus_write(dev, VE_H264_PPS, reg);
> +
> + // sequence parameters
> + reg = 0;
> + reg |= (sps->chroma_format_idc & 0x7) << 19;
> + reg |= (sps->pic_width_in_mbs_minus1 & 0xff) << 8;
> + reg |= sps->pic_height_in_map_units_minus1 & 0xff;
> + if (sps->flags & V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY)
> + reg |= VE_H264_SPS_MBS_ONLY;
> + if (sps->flags & V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD)
> + reg |= VE_H264_SPS_MB_ADAPTIVE_FRAME_FIELD;
> + if (sps->flags & V4L2_H264_SPS_FLAG_DIRECT_8X8_INFERENCE)
> + reg |= VE_H264_SPS_DIRECT_8X8_INFERENCE;
> + cedrus_write(dev, VE_H264_SPS, reg);
> +
> + // slice parameters
> + reg = 0;
> + reg |= decode->nal_ref_idc ? BIT(12) : 0;
> + reg |= (slice->slice_type & 0xf) << 8;
> + reg |= slice->cabac_init_idc & 0x3;
> + reg |= VE_H264_SHS_FIRST_SLICE_IN_PIC;
> + if (slice->flags & V4L2_H264_SLICE_FLAG_FIELD_PIC)
> + reg |= VE_H264_SHS_FIELD_PIC;
> + if (slice->flags & V4L2_H264_SLICE_FLAG_BOTTOM_FIELD)
> + reg |= VE_H264_SHS_BOTTOM_FIELD;
> + if (slice->flags & V4L2_H264_SLICE_FLAG_DIRECT_SPATIAL_MV_PRED)
> + reg |= VE_H264_SHS_DIRECT_SPATIAL_MV_PRED;
> + cedrus_write(dev, VE_H264_SHS, reg);
> +
> + reg = 0;
> + reg |= VE_H264_SHS2_NUM_REF_IDX_ACTIVE_OVRD;
> + reg |= (slice->num_ref_idx_l0_active_minus1 & 0x1f) << 24;
> + reg |= (slice->num_ref_idx_l1_active_minus1 & 0x1f) << 16;
> + reg |= (slice->disable_deblocking_filter_idc & 0x3) << 8;
> + reg |= (slice->slice_alpha_c0_offset_div2 & 0xf) << 4;
> + reg |= slice->slice_beta_offset_div2 & 0xf;
> + cedrus_write(dev, VE_H264_SHS2, reg);
> +
> + reg = 0;
> + if (!(scaling && (pps->flags &
> V4L2_H264_PPS_FLAG_PIC_SCALING_MATRIX_PRESENT))) + reg |=
> VE_H264_SHS_QP_SCALING_MATRIX_DEFAULT;
> + reg |= (pps->second_chroma_qp_index_offset & 0x3f) << 16;
> + reg |= (pps->chroma_qp_index_offset & 0x3f) << 8;
> + reg |= (pps->pic_init_qp_minus26 + 26 + slice->slice_qp_delta) &
0x3f;
> + cedrus_write(dev, VE_H264_SHS_QP, reg);
> +
> + // clear status flags
> + cedrus_write(dev, VE_H264_STATUS, cedrus_read(dev,
VE_H264_STATUS));

I'm not sure clearing status here is needed. Do you have any case where it is
need? Maybe if some error happened before and cedrus_h264_irq_clear() wasn't
cleared. I'm fine either way.

> +
> + // enable int
> + reg = cedrus_read(dev, VE_H264_CTRL);
> + cedrus_write(dev, VE_H264_CTRL, reg |
> + VE_H264_CTRL_SLICE_DECODE_INT |
> + VE_H264_CTRL_DECODE_ERR_INT |
> + VE_H264_CTRL_VLD_DATA_REQ_INT);

Since this is the only place where you set VE_H264_CTRL, I wouldn't preserve
previous content. This mode is also capable of decoding VP8 and AVS. So in
theory, if user would want to decode H264 and VP8 videos at the same time,
preserving content will probably corrupt your output. I would just set all
other bits to 0. What do you think? I tested this without preservation and it
works fine.

> +}
> +
> +static enum cedrus_irq_status
> +cedrus_h264_irq_status(struct cedrus_ctx *ctx)
> +{
> + struct cedrus_dev *dev = ctx->dev;
> + u32 reg = cedrus_read(dev, VE_H264_STATUS);
> +
> + if (reg & (VE_H264_STATUS_DECODE_ERR_INT |
> + VE_H264_STATUS_VLD_DATA_REQ_INT))
> + return CEDRUS_IRQ_ERROR;
> +
> + if (reg & VE_H264_CTRL_SLICE_DECODE_INT)
> + return CEDRUS_IRQ_OK;
> +
> + return CEDRUS_IRQ_NONE;
> +}
> +
> +static void cedrus_h264_irq_clear(struct cedrus_ctx *ctx)
> +{
> + struct cedrus_dev *dev = ctx->dev;
> +
> + cedrus_write(dev, VE_H264_STATUS,
> + VE_H264_STATUS_INT_MASK);
> +}
> +
> +static void cedrus_h264_irq_disable(struct cedrus_ctx *ctx)
> +{
> + struct cedrus_dev *dev = ctx->dev;
> + u32 reg = cedrus_read(dev, VE_H264_CTRL);
> +
> + cedrus_write(dev, VE_H264_CTRL,
> + reg & ~VE_H264_CTRL_INT_MASK);
> +}
> +
> +static void cedrus_h264_setup(struct cedrus_ctx *ctx,
> + struct cedrus_run *run)
> +{
> + struct cedrus_dev *dev = ctx->dev;
> +
> + cedrus_engine_enable(dev, CEDRUS_CODEC_H264);
> +
> + cedrus_write(dev, VE_H264_SDROT_CTRL, 0);
> + cedrus_write(dev, VE_H264_EXTRA_BUFFER1,
> + ctx->codec.h264.pic_info_buf_dma);
> + cedrus_write(dev, VE_H264_EXTRA_BUFFER2,
> + ctx->codec.h264.neighbor_info_buf_dma);
> +
> + cedrus_write_scaling_lists(ctx, run);
> + cedrus_write_frame_list(ctx, run);
> +
> + cedrus_set_params(ctx, run);
> +}
> +
> +static int cedrus_h264_start(struct cedrus_ctx *ctx)
> +{
> + struct cedrus_dev *dev = ctx->dev;
> + unsigned int field_size;
> + unsigned int mv_col_size;
> + int ret;
> +
> + /*
> + * FIXME: It seems that the H6 cedarX code is using a formula
> + * here based on the size of the frame, while all the older
> + * code is using a fixed size, so that might need to be
> + * changed at some point.
> + */
> + ctx->codec.h264.pic_info_buf =
> + dma_alloc_coherent(dev->dev, CEDRUS_PIC_INFO_BUF_SIZE,
> + &ctx-
>codec.h264.pic_info_buf_dma,
> + GFP_KERNEL);
> + if (!ctx->codec.h264.pic_info_buf)
> + return -ENOMEM;
> +
> + /*
> + * That buffer is supposed to be 16kiB in size, and be aligned
> + * on 16kiB as well. However, dma_alloc_coherent provides the
> + * guarantee that we'll have a CPU and DMA address aligned on
> + * the smallest page order that is greater to the requested
> + * size, so we don't have to overallocate.
> + */
> + ctx->codec.h264.neighbor_info_buf =
> + dma_alloc_coherent(dev->dev,
CEDRUS_NEIGHBOR_INFO_BUF_SIZE,
> + &ctx-
>codec.h264.neighbor_info_buf_dma,
> + GFP_KERNEL);
> + if (!ctx->codec.h264.neighbor_info_buf) {
> + ret = -ENOMEM;
> + goto err_pic_buf;
> + }
> +
> + field_size = DIV_ROUND_UP(ctx->src_fmt.width, 16) *
> + DIV_ROUND_UP(ctx->src_fmt.height, 16) * 16;
> +
> + /*
> + * FIXME: This is actually conditional to
> + * V4L2_H264_SPS_FLAG_DIRECT_8X8_INFERENCE not being set, we
> + * might have to rework this if memory efficiency ever is
> + * something we need to work on.
> + */
> + field_size = field_size * 2;
> +
> + /*
> + * FIXME: This is actually conditional to
> + * V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY not being set, we might
> + * have to rework this if memory efficiency ever is something
> + * we need to work on.
> + */
> + field_size = field_size * 2;
> + ctx->codec.h264.mv_col_buf_field_size = field_size;

CedarX code aligns this buffer to 1024. Should we do it too just to be on the
safe side? I don't think it cost us anything due to dma_alloc_coherent()
alignments.

Sorry again for a bit late in-depth review.

Best regards,
Jernej

> +
> + mv_col_size = field_size * 2 * CEDRUS_H264_FRAME_NUM;
> + ctx->codec.h264.mv_col_buf_size = mv_col_size;
> + ctx->codec.h264.mv_col_buf = dma_alloc_coherent(dev->dev,
> +
ctx->codec.h264.mv_col_buf_size,
> +
&ctx->codec.h264.mv_col_buf_dma,
> +
GFP_KERNEL);
> + if (!ctx->codec.h264.mv_col_buf) {
> + ret = -ENOMEM;
> + goto err_neighbor_buf;
> + }
> +
> + return 0;
> +
> +err_neighbor_buf:
> + dma_free_coherent(dev->dev, CEDRUS_NEIGHBOR_INFO_BUF_SIZE,
> + ctx->codec.h264.neighbor_info_buf,
> + ctx->codec.h264.neighbor_info_buf_dma);
> +
> +err_pic_buf:
> + dma_free_coherent(dev->dev, CEDRUS_PIC_INFO_BUF_SIZE,
> + ctx->codec.h264.pic_info_buf,
> + ctx->codec.h264.pic_info_buf_dma);
> + return ret;
> +}
> +
> +static void cedrus_h264_stop(struct cedrus_ctx *ctx)
> +{
> + struct cedrus_dev *dev = ctx->dev;
> +
> + dma_free_coherent(dev->dev, ctx->codec.h264.mv_col_buf_size,
> + ctx->codec.h264.mv_col_buf,
> + ctx->codec.h264.mv_col_buf_dma);
> + dma_free_coherent(dev->dev, CEDRUS_NEIGHBOR_INFO_BUF_SIZE,
> + ctx->codec.h264.neighbor_info_buf,
> + ctx->codec.h264.neighbor_info_buf_dma);
> + dma_free_coherent(dev->dev, CEDRUS_PIC_INFO_BUF_SIZE,
> + ctx->codec.h264.pic_info_buf,
> + ctx->codec.h264.pic_info_buf_dma);
> +}
> +
> +static void cedrus_h264_trigger(struct cedrus_ctx *ctx)
> +{
> + struct cedrus_dev *dev = ctx->dev;
> +
> + cedrus_write(dev, VE_H264_TRIGGER_TYPE,
> + VE_H264_TRIGGER_TYPE_AVC_SLICE_DECODE);
> +}
> +
> +struct cedrus_dec_ops cedrus_dec_ops_h264 = {
> + .irq_clear = cedrus_h264_irq_clear,
> + .irq_disable = cedrus_h264_irq_disable,
> + .irq_status = cedrus_h264_irq_status,
> + .setup = cedrus_h264_setup,
> + .start = cedrus_h264_start,
> + .stop = cedrus_h264_stop,
> + .trigger = cedrus_h264_trigger,
> +};
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
> b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c index
> 0acf219a8c91..ab402b0cac4e 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
> @@ -46,6 +46,10 @@ int cedrus_engine_enable(struct cedrus_dev *dev, enum
> cedrus_codec codec) reg |= VE_MODE_DEC_MPEG;
> break;
>
> + case CEDRUS_CODEC_H264:
> + reg |= VE_MODE_DEC_H264;
> + break;
> +
> default:
> return -EINVAL;
> }
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_regs.h
> b/drivers/staging/media/sunxi/cedrus/cedrus_regs.h index
> de2d6b6f64bf..3e9931416e45 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_regs.h
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_regs.h
> @@ -232,4 +232,95 @@
> #define VE_DEC_MPEG_ROT_LUMA (VE_ENGINE_DEC_MPEG +
0xcc)
> #define VE_DEC_MPEG_ROT_CHROMA
(VE_ENGINE_DEC_MPEG + 0xd0)
>
> +#define VE_H264_SPS 0x200
> +#define VE_H264_SPS_MBS_ONLY BIT(18)
> +#define VE_H264_SPS_MB_ADAPTIVE_FRAME_FIELD BIT(17)
> +#define VE_H264_SPS_DIRECT_8X8_INFERENCE BIT(16)
> +
> +#define VE_H264_PPS 0x204
> +#define VE_H264_PPS_ENTROPY_CODING_MODE BIT(15)
> +#define VE_H264_PPS_WEIGHTED_PRED BIT(4)
> +#define VE_H264_PPS_CONSTRAINED_INTRA_PRED BIT(1)
> +#define VE_H264_PPS_TRANSFORM_8X8_MODE BIT(0)
> +
> +#define VE_H264_SHS 0x208
> +#define VE_H264_SHS_FIRST_SLICE_IN_PIC BIT(5)
> +#define VE_H264_SHS_FIELD_PIC BIT(4)
> +#define VE_H264_SHS_BOTTOM_FIELD BIT(3)
> +#define VE_H264_SHS_DIRECT_SPATIAL_MV_PRED BIT(2)
> +
> +#define VE_H264_SHS2 0x20c
> +#define VE_H264_SHS2_NUM_REF_IDX_ACTIVE_OVRD BIT(12)
> +
> +#define VE_H264_SHS_WP 0x210
> +
> +#define VE_H264_SHS_QP 0x21c
> +#define VE_H264_SHS_QP_SCALING_MATRIX_DEFAULT BIT(24)
> +
> +#define VE_H264_CTRL 0x220
> +#define VE_H264_CTRL_VLD_DATA_REQ_INT BIT(2)
> +#define VE_H264_CTRL_DECODE_ERR_INT BIT(1)
> +#define VE_H264_CTRL_SLICE_DECODE_INT BIT(0)
> +
> +#define VE_H264_CTRL_INT_MASK (VE_H264_CTRL_VLD_DATA_REQ_INT | \
> +
VE_H264_CTRL_DECODE_ERR_INT | \
> +
VE_H264_CTRL_SLICE_DECODE_INT)
> +
> +#define VE_H264_TRIGGER_TYPE 0x224
> +#define VE_H264_TRIGGER_TYPE_AVC_SLICE_DECODE (8 << 0)
> +#define VE_H264_TRIGGER_TYPE_INIT_SWDEC (7 << 0)
> +
> +#define VE_H264_STATUS 0x228
> +#define VE_H264_STATUS_VLD_DATA_REQ_INT
VE_H264_CTRL_VLD_DATA_REQ_INT
> +#define VE_H264_STATUS_DECODE_ERR_INT
VE_H264_CTRL_DECODE_ERR_INT
> +#define VE_H264_STATUS_SLICE_DECODE_INT
VE_H264_CTRL_SLICE_DECODE_INT
> +
> +#define VE_H264_STATUS_INT_MASK
VE_H264_CTRL_INT_MASK
> +
> +#define VE_H264_CUR_MB_NUM 0x22c
> +
> +#define VE_H264_VLD_ADDR 0x230
> +#define VE_H264_VLD_ADDR_FIRST BIT(30)
> +#define VE_H264_VLD_ADDR_LAST BIT(29)
> +#define VE_H264_VLD_ADDR_VALID BIT(28)
> +#define VE_H264_VLD_ADDR_VAL(x) (((x) & 0x0ffffff0) |
((x) >> 28))
> +
> +#define VE_H264_VLD_OFFSET 0x234
> +#define VE_H264_VLD_LEN 0x238
> +#define VE_H264_VLD_END 0x23c
> +#define VE_H264_SDROT_CTRL 0x240
> +#define VE_H264_OUTPUT_FRAME_IDX 0x24c
> +#define VE_H264_EXTRA_BUFFER1 0x250
> +#define VE_H264_EXTRA_BUFFER2 0x254
> +#define VE_H264_BASIC_BITS 0x2dc
> +#define VE_AVC_SRAM_PORT_OFFSET 0x2e0
> +#define VE_AVC_SRAM_PORT_DATA 0x2e4
> +
> +#define VE_ISP_INPUT_SIZE 0xa00
> +#define VE_ISP_INPUT_STRIDE 0xa04
> +#define VE_ISP_CTRL 0xa08
> +#define VE_ISP_INPUT_LUMA 0xa78
> +#define VE_ISP_INPUT_CHROMA 0xa7c
> +
> +#define VE_AVC_PARAM 0xb04
> +#define VE_AVC_QP 0xb08
> +#define VE_AVC_MOTION_EST 0xb10
> +#define VE_AVC_CTRL 0xb14
> +#define VE_AVC_TRIGGER 0xb18
> +#define VE_AVC_STATUS 0xb1c
> +#define VE_AVC_BASIC_BITS 0xb20
> +#define VE_AVC_UNK_BUF 0xb60
> +#define VE_AVC_VLE_ADDR 0xb80
> +#define VE_AVC_VLE_END 0xb84
> +#define VE_AVC_VLE_OFFSET 0xb88
> +#define VE_AVC_VLE_MAX 0xb8c
> +#define VE_AVC_VLE_LENGTH 0xb90
> +#define VE_AVC_REF_LUMA 0xba0
> +#define VE_AVC_REF_CHROMA 0xba4
> +#define VE_AVC_REC_LUMA 0xbb0
> +#define VE_AVC_REC_CHROMA 0xbb4
> +#define VE_AVC_REF_SLUMA 0xbb8
> +#define VE_AVC_REC_SLUMA 0xbbc
> +#define VE_AVC_MB_INFO 0xbc0
> +
> #endif
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> b/drivers/staging/media/sunxi/cedrus/cedrus_video.c index
> b5cc79389d67..67062900f87a 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> @@ -38,6 +38,10 @@ static struct cedrus_format cedrus_formats[] = {
> .directions = CEDRUS_DECODE_SRC,
> },
> {
> + .pixelformat = V4L2_PIX_FMT_H264_SLICE,
> + .directions = CEDRUS_DECODE_SRC,
> + },
> + {
> .pixelformat = V4L2_PIX_FMT_SUNXI_TILED_NV12,
> .directions = CEDRUS_DECODE_DST,
> },
> @@ -100,6 +104,7 @@ static void cedrus_prepare_format(struct v4l2_pix_format
> *pix_fmt)
>
> switch (pix_fmt->pixelformat) {
> case V4L2_PIX_FMT_MPEG2_SLICE:
> + case V4L2_PIX_FMT_H264_SLICE:
> /* Zero bytes per line for encoded source. */
> bytesperline = 0;
>
> @@ -454,6 +459,10 @@ static int cedrus_start_streaming(struct vb2_queue *vq,
> unsigned int count) ctx->current_codec = CEDRUS_CODEC_MPEG2;
> break;
>
> + case V4L2_PIX_FMT_H264_SLICE:
> + ctx->current_codec = CEDRUS_CODEC_H264;
> + break;
> +
> default:
> return -EINVAL;
> }