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Message-ID: <CAPBb6MV-Mdd-N7RYODCk3ASswL8-+YuwZmZZ8p6atc=FY45TCA@mail.gmail.com>
Date: Wed, 17 Mar 2021 12:13:55 +0900
From: Alexandre Courbot <acourbot@...omium.org>
To: Ezequiel Garcia <ezequiel@...guardiasur.com.ar>
Cc: Yunfei Dong <yunfei.dong@...iatek.com>,
Tiffany Lin <tiffany.lin@...iatek.com>,
Andrew-CT Chen <andrew-ct.chen@...iatek.com>,
Rob Herring <robh+dt@...nel.org>,
Mauro Carvalho Chehab <mchehab@...nel.org>,
Hans Verkuil <hverkuil-cisco@...all.nl>,
linux-media <linux-media@...r.kernel.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
"moderated list:ARM/Mediatek SoC support"
<linux-mediatek@...ts.infradead.org>
Subject: Re: [PATCH v3 06/15] media: mtk-vcodec: vdec: support stateless H.264 decoding
On Tue, Mar 16, 2021 at 7:08 AM Ezequiel Garcia
<ezequiel@...guardiasur.com.ar> wrote:
>
> Hi Alex,
>
> On Mon, 15 Mar 2021 at 08:28, Alexandre Courbot <acourbot@...omium.org> wrote:
> >
> > Hi Ezequiel,
> >
> > On Thu, Mar 4, 2021 at 6:47 AM Ezequiel Garcia
> > <ezequiel@...guardiasur.com.ar> wrote:
> > >
> > > Hi Alex,
> > >
> > > Thanks for the patch.
> > >
> > > On Fri, 26 Feb 2021 at 07:06, Alexandre Courbot <acourbot@...omium.org> wrote:
> > > >
> > > > From: Yunfei Dong <yunfei.dong@...iatek.com>
> > > >
> > > > Add support for H.264 decoding using the stateless API, as supported by
> > > > MT8183. This support takes advantage of the V4L2 H.264 reference list
> > > > builders.
> > > >
> > > > Signed-off-by: Yunfei Dong <yunfei.dong@...iatek.com>
> > > > [acourbot: refactor, cleanup and split]
> > > > Co-developed-by: Alexandre Courbot <acourbot@...omium.org>
> > > > Signed-off-by: Alexandre Courbot <acourbot@...omium.org>
> > > > ---
> > > > drivers/media/platform/Kconfig | 1 +
> > > > drivers/media/platform/mtk-vcodec/Makefile | 1 +
> > > > .../mtk-vcodec/vdec/vdec_h264_req_if.c | 807 ++++++++++++++++++
> > > > .../media/platform/mtk-vcodec/vdec_drv_if.c | 3 +
> > > > .../media/platform/mtk-vcodec/vdec_drv_if.h | 1 +
> > > > 5 files changed, 813 insertions(+)
> > > > create mode 100644 drivers/media/platform/mtk-vcodec/vdec/vdec_h264_req_if.c
> > > >
> > > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > > > index fd1831e97b22..c27db5643712 100644
> > > > --- a/drivers/media/platform/Kconfig
> > > > +++ b/drivers/media/platform/Kconfig
> > > > @@ -295,6 +295,7 @@ config VIDEO_MEDIATEK_VCODEC
> > > > select V4L2_MEM2MEM_DEV
> > > > select VIDEO_MEDIATEK_VCODEC_VPU if VIDEO_MEDIATEK_VPU
> > > > select VIDEO_MEDIATEK_VCODEC_SCP if MTK_SCP
> > > > + select V4L2_H264
> > > > help
> > > > Mediatek video codec driver provides HW capability to
> > > > encode and decode in a range of video formats on MT8173
> > > > diff --git a/drivers/media/platform/mtk-vcodec/Makefile b/drivers/media/platform/mtk-vcodec/Makefile
> > > > index 4ba93d838ab6..ca8e9e7a9c4e 100644
> > > > --- a/drivers/media/platform/mtk-vcodec/Makefile
> > > > +++ b/drivers/media/platform/mtk-vcodec/Makefile
> > > > @@ -7,6 +7,7 @@ obj-$(CONFIG_VIDEO_MEDIATEK_VCODEC) += mtk-vcodec-dec.o \
> > > > mtk-vcodec-dec-y := vdec/vdec_h264_if.o \
> > > > vdec/vdec_vp8_if.o \
> > > > vdec/vdec_vp9_if.o \
> > > > + vdec/vdec_h264_req_if.o \
> > > > mtk_vcodec_dec_drv.o \
> > > > vdec_drv_if.o \
> > > > vdec_vpu_if.o \
> > > > diff --git a/drivers/media/platform/mtk-vcodec/vdec/vdec_h264_req_if.c b/drivers/media/platform/mtk-vcodec/vdec/vdec_h264_req_if.c
> > > > new file mode 100644
> > > > index 000000000000..2fbbfbbcfbec
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/mtk-vcodec/vdec/vdec_h264_req_if.c
> > > > @@ -0,0 +1,807 @@
> > > > +// SPDX-License-Identifier: GPL-2.0
> > > > +
> > > > +#include <linux/module.h>
> > > > +#include <linux/slab.h>
> > > > +#include <media/v4l2-mem2mem.h>
> > > > +#include <media/v4l2-h264.h>
> > > > +#include <media/videobuf2-dma-contig.h>
> > > > +
> > > > +#include "../vdec_drv_if.h"
> > > > +#include "../mtk_vcodec_util.h"
> > > > +#include "../mtk_vcodec_dec.h"
> > > > +#include "../mtk_vcodec_intr.h"
> > > > +#include "../vdec_vpu_if.h"
> > > > +#include "../vdec_drv_base.h"
> > > > +
> > > > +#define NAL_NON_IDR_SLICE 0x01
> > > > +#define NAL_IDR_SLICE 0x05
> > > > +#define NAL_H264_PPS 0x08
> > >
> > > Not used?
> > >
> > > > +#define NAL_TYPE(value) ((value) & 0x1F)
> > > > +
> > >
> > > I believe you may not need the NAL type.
> >
> > True, removed this block of defines.
> >
> > >
> > > > +#define BUF_PREDICTION_SZ (64 * 4096)
> > > > +#define MB_UNIT_LEN 16
> > > > +
> > > > +/* get used parameters for sps/pps */
> > > > +#define GET_MTK_VDEC_FLAG(cond, flag) \
> > > > + { dst_param->cond = ((src_param->flags & flag) ? (1) : (0)); }
> > > > +#define GET_MTK_VDEC_PARAM(param) \
> > > > + { dst_param->param = src_param->param; }
> > > > +/* motion vector size (bytes) for every macro block */
> > > > +#define HW_MB_STORE_SZ 64
> > > > +
> > > > +#define H264_MAX_FB_NUM 17
> > > > +#define H264_MAX_MV_NUM 32
> > > > +#define HDR_PARSING_BUF_SZ 1024
> > > > +
> > > > +/**
> > > > + * struct mtk_h264_dpb_info - h264 dpb information
> > > > + * @y_dma_addr: Y bitstream physical address
> > > > + * @c_dma_addr: CbCr bitstream physical address
> > > > + * @reference_flag: reference picture flag (short/long term reference picture)
> > > > + * @field: field picture flag
> > > > + */
> > > > +struct mtk_h264_dpb_info {
> > > > + dma_addr_t y_dma_addr;
> > > > + dma_addr_t c_dma_addr;
> > > > + int reference_flag;
> > > > + int field;
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct mtk_h264_sps_param - parameters for sps
> > > > + */
> > > > +struct mtk_h264_sps_param {
> > > > + unsigned char chroma_format_idc;
> > > > + unsigned char bit_depth_luma_minus8;
> > > > + unsigned char bit_depth_chroma_minus8;
> > > > + unsigned char log2_max_frame_num_minus4;
> > > > + unsigned char pic_order_cnt_type;
> > > > + unsigned char log2_max_pic_order_cnt_lsb_minus4;
> > > > + unsigned char max_num_ref_frames;
> > > > + unsigned char separate_colour_plane_flag;
> > > > + unsigned short pic_width_in_mbs_minus1;
> > > > + unsigned short pic_height_in_map_units_minus1;
> > > > + unsigned int max_frame_nums;
> > > > + unsigned char qpprime_y_zero_transform_bypass_flag;
> > > > + unsigned char delta_pic_order_always_zero_flag;
> > > > + unsigned char frame_mbs_only_flag;
> > > > + unsigned char mb_adaptive_frame_field_flag;
> > > > + unsigned char direct_8x8_inference_flag;
> > > > + unsigned char reserved[3];
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct mtk_h264_pps_param - parameters for pps
> > > > + */
> > > > +struct mtk_h264_pps_param {
> > > > + unsigned char num_ref_idx_l0_default_active_minus1;
> > > > + unsigned char num_ref_idx_l1_default_active_minus1;
> > > > + unsigned char weighted_bipred_idc;
> > > > + char pic_init_qp_minus26;
> > > > + char chroma_qp_index_offset;
> > > > + char second_chroma_qp_index_offset;
> > > > + unsigned char entropy_coding_mode_flag;
> > > > + unsigned char pic_order_present_flag;
> > > > + unsigned char deblocking_filter_control_present_flag;
> > > > + unsigned char constrained_intra_pred_flag;
> > > > + unsigned char weighted_pred_flag;
> > > > + unsigned char redundant_pic_cnt_present_flag;
> > > > + unsigned char transform_8x8_mode_flag;
> > > > + unsigned char scaling_matrix_present_flag;
> > > > + unsigned char reserved[2];
> > > > +};
> > > > +
> > > > +struct slice_api_h264_scaling_matrix {
> > >
> > > Equal to v4l2_ctrl_h264_scaling_matrix ?
> > > Well I guess you don't want to mix a hardware-specific
> > > thing with the V4L2 API maybe.
> >
> > That's the idea. Although the layout match and the ABI is now stable,
> > I think this communicates better the fact that this is a firmware
> > structure.
> >
> > >
> > > > + unsigned char scaling_list_4x4[6][16];
> > > > + unsigned char scaling_list_8x8[6][64];
> > > > +};
> > > > +
> > > > +struct slice_h264_dpb_entry {
> > > > + unsigned long long reference_ts;
> > > > + unsigned short frame_num;
> > > > + unsigned short pic_num;
> > > > + /* Note that field is indicated by v4l2_buffer.field */
> > > > + int top_field_order_cnt;
> > > > + int bottom_field_order_cnt;
> > > > + unsigned int flags; /* V4L2_H264_DPB_ENTRY_FLAG_* */
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct slice_api_h264_decode_param - parameters for decode.
> > > > + */
> > > > +struct slice_api_h264_decode_param {
> > > > + struct slice_h264_dpb_entry dpb[16];
> > >
> > > V4L2_H264_NUM_DPB_ENTRIES?
> >
> > For the same reason as above (this being a firmware structure), I
> > think it is clearer to not use the kernel definitions here.
> >
> > >
> > > > + unsigned short num_slices;
> > > > + unsigned short nal_ref_idc;
> > > > + unsigned char ref_pic_list_p0[32];
> > > > + unsigned char ref_pic_list_b0[32];
> > > > + unsigned char ref_pic_list_b1[32];
> > >
> > > V4L2_H264_REF_LIST_LEN?
> >
> > Ditto.
> >
> > >
> > > > + int top_field_order_cnt;
> > > > + int bottom_field_order_cnt;
> > > > + unsigned int flags; /* V4L2_H264_DECODE_PARAM_FLAG_* */
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct mtk_h264_dec_slice_param - parameters for decode current frame
> > > > + */
> > > > +struct mtk_h264_dec_slice_param {
> > > > + struct mtk_h264_sps_param sps;
> > > > + struct mtk_h264_pps_param pps;
> > > > + struct slice_api_h264_scaling_matrix scaling_matrix;
> > > > + struct slice_api_h264_decode_param decode_params;
> > > > + struct mtk_h264_dpb_info h264_dpb_info[16];
> > >
> > > V4L2_H264_NUM_DPB_ENTRIES?
> >
> > Ditto.
> >
> > >
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct h264_fb - h264 decode frame buffer information
> > > > + * @vdec_fb_va : virtual address of struct vdec_fb
> > > > + * @y_fb_dma : dma address of Y frame buffer (luma)
> > > > + * @c_fb_dma : dma address of C frame buffer (chroma)
> > > > + * @poc : picture order count of frame buffer
> > > > + * @reserved : for 8 bytes alignment
> > > > + */
> > > > +struct h264_fb {
> > > > + uint64_t vdec_fb_va;
> > > > + uint64_t y_fb_dma;
> > > > + uint64_t c_fb_dma;
> > > > + int32_t poc;
> > > > + uint32_t reserved;
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct vdec_h264_dec_info - decode information
> > > > + * @dpb_sz : decoding picture buffer size
> > > > + * @resolution_changed : resoltion change happen
> > > > + * @realloc_mv_buf : flag to notify driver to re-allocate mv buffer
> > > > + * @cap_num_planes : number planes of capture buffer
> > > > + * @bs_dma : Input bit-stream buffer dma address
> > > > + * @y_fb_dma : Y frame buffer dma address
> > > > + * @c_fb_dma : C frame buffer dma address
> > > > + * @vdec_fb_va : VDEC frame buffer struct virtual address
> > > > + */
> > > > +struct vdec_h264_dec_info {
> > > > + uint32_t dpb_sz;
> > > > + uint32_t resolution_changed;
> > > > + uint32_t realloc_mv_buf;
> > > > + uint32_t cap_num_planes;
> > > > + uint64_t bs_dma;
> > > > + uint64_t y_fb_dma;
> > > > + uint64_t c_fb_dma;
> > > > + uint64_t vdec_fb_va;
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct vdec_h264_vsi - shared memory for decode information exchange
> > > > + * between VPU and Host.
> > > > + * The memory is allocated by VPU then mapping to Host
> > > > + * in vpu_dec_init() and freed in vpu_dec_deinit()
> > > > + * by VPU.
> > > > + * AP-W/R : AP is writer/reader on this item
> > > > + * VPU-W/R: VPU is write/reader on this item
> > > > + * @pred_buf_dma : HW working predication buffer dma address (AP-W, VPU-R)
> > > > + * @mv_buf_dma : HW working motion vector buffer dma address (AP-W, VPU-R)
> > > > + * @dec : decode information (AP-R, VPU-W)
> > > > + * @pic : picture information (AP-R, VPU-W)
> > > > + * @crop : crop information (AP-R, VPU-W)
> > > > + */
> > > > +struct vdec_h264_vsi {
> > > > + uint64_t pred_buf_dma;
> > > > + uint64_t mv_buf_dma[H264_MAX_MV_NUM];
> > > > + struct vdec_h264_dec_info dec;
> > > > + struct vdec_pic_info pic;
> > > > + struct v4l2_rect crop;
> > > > + struct mtk_h264_dec_slice_param h264_slice_params;
> > > > +};
> > > > +
> > > > +/**
> > > > + * struct vdec_h264_slice_inst - h264 decoder instance
> > > > + * @num_nalu : how many nalus be decoded
> > > > + * @ctx : point to mtk_vcodec_ctx
> > > > + * @pred_buf : HW working predication buffer
> > > > + * @mv_buf : HW working motion vector buffer
> > > > + * @vpu : VPU instance
> > > > + * @vsi_ctx : Local VSI data for this decoding context
> > > > + */
> > > > +struct vdec_h264_slice_inst {
> > > > + unsigned int num_nalu;
> > > > + struct mtk_vcodec_ctx *ctx;
> > > > + struct mtk_vcodec_mem pred_buf;
> > > > + struct mtk_vcodec_mem mv_buf[H264_MAX_MV_NUM];
> > > > + struct vdec_vpu_inst vpu;
> > > > + struct vdec_h264_vsi vsi_ctx;
> > > > + struct mtk_h264_dec_slice_param h264_slice_param;
> > > > +
> > > > + struct v4l2_h264_dpb_entry dpb[16];
> > > > +};
> > > > +
> > > > +static void *get_ctrl_ptr(struct mtk_vcodec_ctx *ctx,
> > > > + int id)
> > > > +{
> > > > + struct v4l2_ctrl *ctrl = v4l2_ctrl_find(&ctx->ctrl_hdl, id);
> > > > +
> > > > + return ctrl->p_cur.p;
> > > > +}
> > > > +
> > > > +static void get_h264_dpb_list(struct vdec_h264_slice_inst *inst,
> > > > + struct mtk_h264_dec_slice_param *slice_param)
> > > > +{
> > > > + struct vb2_queue *vq;
> > > > + struct vb2_buffer *vb;
> > > > + struct vb2_v4l2_buffer *vb2_v4l2;
> > > > + u64 index;
> > > > +
> > > > + vq = v4l2_m2m_get_vq(inst->ctx->m2m_ctx,
> > > > + V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE);
> > > > +
> > > > + for (index = 0; index < 16; index++) {
> > >
> > > Ditto, some macro instead of 16.
> >
> > Changed this to use ARRAY_SIZE() which is appropriate here.
> >
> > >
> > > > + const struct slice_h264_dpb_entry *dpb;
> > > > + int vb2_index;
> > > > +
> > > > + dpb = &slice_param->decode_params.dpb[index];
> > > > + if (!(dpb->flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE)) {
> > > > + slice_param->h264_dpb_info[index].reference_flag = 0;
> > > > + continue;
> > > > + }
> > > > +
> > > > + vb2_index = vb2_find_timestamp(vq, dpb->reference_ts, 0);
> > > > + if (vb2_index < 0) {
> > > > + mtk_vcodec_err(inst, "Reference invalid: dpb_index(%lld) reference_ts(%lld)",
> > > > + index, dpb->reference_ts);
> > > > + continue;
> > > > + }
> > > > + /* 1 for short term reference, 2 for long term reference */
> > > > + if (!(dpb->flags & V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM))
> > > > + slice_param->h264_dpb_info[index].reference_flag = 1;
> > > > + else
> > > > + slice_param->h264_dpb_info[index].reference_flag = 2;
> > > > +
> > > > + vb = vq->bufs[vb2_index];
> > > > + vb2_v4l2 = container_of(vb, struct vb2_v4l2_buffer, vb2_buf);
> > > > + slice_param->h264_dpb_info[index].field = vb2_v4l2->field;
> > > > +
> > > > + slice_param->h264_dpb_info[index].y_dma_addr =
> > > > + vb2_dma_contig_plane_dma_addr(vb, 0);
> > > > + if (inst->ctx->q_data[MTK_Q_DATA_DST].fmt->num_planes == 2) {
> > > > + slice_param->h264_dpb_info[index].c_dma_addr =
> > > > + vb2_dma_contig_plane_dma_addr(vb, 1);
> > > > + }
> > > > + }
> > > > +}
> > > > +
> > > > +static void get_h264_sps_parameters(struct mtk_h264_sps_param *dst_param,
> > > > + const struct v4l2_ctrl_h264_sps *src_param)
> > > > +{
> > > > + GET_MTK_VDEC_PARAM(chroma_format_idc);
> > > > + GET_MTK_VDEC_PARAM(bit_depth_luma_minus8);
> > > > + GET_MTK_VDEC_PARAM(bit_depth_chroma_minus8);
> > > > + GET_MTK_VDEC_PARAM(log2_max_frame_num_minus4);
> > > > + GET_MTK_VDEC_PARAM(pic_order_cnt_type);
> > > > + GET_MTK_VDEC_PARAM(log2_max_pic_order_cnt_lsb_minus4);
> > > > + GET_MTK_VDEC_PARAM(max_num_ref_frames);
> > > > + GET_MTK_VDEC_PARAM(pic_width_in_mbs_minus1);
> > > > + GET_MTK_VDEC_PARAM(pic_height_in_map_units_minus1);
> > > > +
> > > > + GET_MTK_VDEC_FLAG(separate_colour_plane_flag,
> > > > + V4L2_H264_SPS_FLAG_SEPARATE_COLOUR_PLANE);
> > > > + GET_MTK_VDEC_FLAG(qpprime_y_zero_transform_bypass_flag,
> > > > + V4L2_H264_SPS_FLAG_QPPRIME_Y_ZERO_TRANSFORM_BYPASS);
> > > > + GET_MTK_VDEC_FLAG(delta_pic_order_always_zero_flag,
> > > > + V4L2_H264_SPS_FLAG_DELTA_PIC_ORDER_ALWAYS_ZERO);
> > > > + GET_MTK_VDEC_FLAG(frame_mbs_only_flag,
> > > > + V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY);
> > > > + GET_MTK_VDEC_FLAG(mb_adaptive_frame_field_flag,
> > > > + V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD);
> > > > + GET_MTK_VDEC_FLAG(direct_8x8_inference_flag,
> > > > + V4L2_H264_SPS_FLAG_DIRECT_8X8_INFERENCE);
> > > > +}
> > > > +
> > > > +static void get_h264_pps_parameters(struct mtk_h264_pps_param *dst_param,
> > > > + const struct v4l2_ctrl_h264_pps *src_param)
> > > > +{
> > > > + GET_MTK_VDEC_PARAM(num_ref_idx_l0_default_active_minus1);
> > > > + GET_MTK_VDEC_PARAM(num_ref_idx_l1_default_active_minus1);
> > > > + GET_MTK_VDEC_PARAM(weighted_bipred_idc);
> > > > + GET_MTK_VDEC_PARAM(pic_init_qp_minus26);
> > > > + GET_MTK_VDEC_PARAM(chroma_qp_index_offset);
> > > > + GET_MTK_VDEC_PARAM(second_chroma_qp_index_offset);
> > > > +
> > > > + GET_MTK_VDEC_FLAG(entropy_coding_mode_flag,
> > > > + V4L2_H264_PPS_FLAG_ENTROPY_CODING_MODE);
> > > > + GET_MTK_VDEC_FLAG(pic_order_present_flag,
> > > > + V4L2_H264_PPS_FLAG_BOTTOM_FIELD_PIC_ORDER_IN_FRAME_PRESENT);
> > > > + GET_MTK_VDEC_FLAG(weighted_pred_flag,
> > > > + V4L2_H264_PPS_FLAG_WEIGHTED_PRED);
> > > > + GET_MTK_VDEC_FLAG(deblocking_filter_control_present_flag,
> > > > + V4L2_H264_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT);
> > > > + GET_MTK_VDEC_FLAG(constrained_intra_pred_flag,
> > > > + V4L2_H264_PPS_FLAG_CONSTRAINED_INTRA_PRED);
> > > > + GET_MTK_VDEC_FLAG(redundant_pic_cnt_present_flag,
> > > > + V4L2_H264_PPS_FLAG_REDUNDANT_PIC_CNT_PRESENT);
> > > > + GET_MTK_VDEC_FLAG(transform_8x8_mode_flag,
> > > > + V4L2_H264_PPS_FLAG_TRANSFORM_8X8_MODE);
> > > > + GET_MTK_VDEC_FLAG(scaling_matrix_present_flag,
> > > > + V4L2_H264_PPS_FLAG_SCALING_MATRIX_PRESENT);
> > > > +}
> > > > +
> > > > +static void
> > > > +get_h264_scaling_matrix(struct slice_api_h264_scaling_matrix *dst_matrix,
> > > > + const struct v4l2_ctrl_h264_scaling_matrix *src_matrix)
> > > > +{
> > > > + memcpy(dst_matrix->scaling_list_4x4, src_matrix->scaling_list_4x4,
> > > > + sizeof(dst_matrix->scaling_list_4x4));
> > > > +
> > > > + memcpy(dst_matrix->scaling_list_8x8, src_matrix->scaling_list_8x8,
> > > > + sizeof(dst_matrix->scaling_list_8x8));
> > > > +}
> > > > +
> > > > +static void get_h264_decode_parameters(
> > > > + struct slice_api_h264_decode_param *dst_params,
> > > > + const struct v4l2_ctrl_h264_decode_params *src_params,
> > > > + const struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES])
> > > > +{
> > > > + int i;
> > > > +
> > > > + for (i = 0; i < ARRAY_SIZE(dst_params->dpb); i++) {
> > > > + struct slice_h264_dpb_entry *dst_entry = &dst_params->dpb[i];
> > > > + const struct v4l2_h264_dpb_entry *src_entry = &dpb[i];
> > > > +
> > > > + dst_entry->reference_ts = src_entry->reference_ts;
> > > > + dst_entry->frame_num = src_entry->frame_num;
> > > > + dst_entry->pic_num = src_entry->pic_num;
> > > > + dst_entry->top_field_order_cnt = src_entry->top_field_order_cnt;
> > > > + dst_entry->bottom_field_order_cnt =
> > > > + src_entry->bottom_field_order_cnt;
> > > > + dst_entry->flags = src_entry->flags;
> > > > + }
> > > > +
> > > > + // num_slices is a leftover from the old H.264 support and is ignored
> > > > + // by the firmware.
> > > > + dst_params->num_slices = 0;
> > > > + dst_params->nal_ref_idc = src_params->nal_ref_idc;
> > > > + dst_params->top_field_order_cnt = src_params->top_field_order_cnt;
> > > > + dst_params->bottom_field_order_cnt = src_params->bottom_field_order_cnt;
> > > > + dst_params->flags = src_params->flags;
> > > > +}
> > > > +
> > > > +static bool dpb_entry_match(const struct v4l2_h264_dpb_entry *a,
> > > > + const struct v4l2_h264_dpb_entry *b)
> > > > +{
> > > > + return a->top_field_order_cnt == b->top_field_order_cnt &&
> > > > + a->bottom_field_order_cnt == b->bottom_field_order_cnt;
> > > > +}
> > > > +
> > > > +/*
> > > > + * Move DPB entries of dec_param that refer to a frame already existing in dpb
> > > > + * into the already existing slot in dpb, and move other entries into new slots.
> > > > + *
> > > > + * This function is an adaptation of the similarly-named function in
> > > > + * hantro_h264.c.
> > > > + */
> > > > +static void update_dpb(const struct v4l2_ctrl_h264_decode_params *dec_param,
> > > > + struct v4l2_h264_dpb_entry *dpb)
> > > > +{
> > > > + DECLARE_BITMAP(new, ARRAY_SIZE(dec_param->dpb)) = { 0, };
> > > > + DECLARE_BITMAP(in_use, ARRAY_SIZE(dec_param->dpb)) = { 0, };
> > > > + DECLARE_BITMAP(used, ARRAY_SIZE(dec_param->dpb)) = { 0, };
> > > > + unsigned int i, j;
> > > > +
> > > > + /* Disable all entries by default, and mark the ones in use. */
> > > > + for (i = 0; i < ARRAY_SIZE(dec_param->dpb); i++) {
> > > > + if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE)
> > > > + set_bit(i, in_use);
> > > > + dpb[i].flags &= ~V4L2_H264_DPB_ENTRY_FLAG_ACTIVE;
> > > > + }
> > > > +
> > > > + /* Try to match new DPB entries with existing ones by their POCs. */
> > > > + for (i = 0; i < ARRAY_SIZE(dec_param->dpb); i++) {
> > > > + const struct v4l2_h264_dpb_entry *ndpb = &dec_param->dpb[i];
> > > > +
> > > > + if (!(ndpb->flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE))
> > > > + continue;
> > > > +
> > > > + /*
> > > > + * To cut off some comparisons, iterate only on target DPB
> > > > + * entries were already used.
> > > > + */
> > > > + for_each_set_bit(j, in_use, ARRAY_SIZE(dec_param->dpb)) {
> > > > + struct v4l2_h264_dpb_entry *cdpb;
> > > > +
> > > > + cdpb = &dpb[j];
> > > > + if (!dpb_entry_match(cdpb, ndpb))
> > > > + continue;
> > > > +
> > > > + *cdpb = *ndpb;
> > > > + set_bit(j, used);
> > > > + /* Don't reiterate on this one. */
> > > > + clear_bit(j, in_use);
> > > > + break;
> > > > + }
> > > > +
> > > > + if (j == ARRAY_SIZE(dec_param->dpb))
> > > > + set_bit(i, new);
> > > > + }
> > > > +
> > > > + /* For entries that could not be matched, use remaining free slots. */
> > > > + for_each_set_bit(i, new, ARRAY_SIZE(dec_param->dpb)) {
> > > > + const struct v4l2_h264_dpb_entry *ndpb = &dec_param->dpb[i];
> > > > + struct v4l2_h264_dpb_entry *cdpb;
> > > > +
> > > > + /*
> > > > + * Both arrays are of the same sizes, so there is no way
> > > > + * we can end up with no space in target array, unless
> > > > + * something is buggy.
> > > > + */
> > > > + j = find_first_zero_bit(used, ARRAY_SIZE(dec_param->dpb));
> > > > + if (WARN_ON(j >= ARRAY_SIZE(dec_param->dpb)))
> > > > + return;
> > > > +
> > > > + cdpb = &dpb[j];
> > > > + *cdpb = *ndpb;
> > > > + set_bit(j, used);
> > > > + }
> > > > +}
> > > > +
> > > > +/*
> > > > + * The firmware expects unused reflist entries to have the value 0x20.
> > > > + */
> > > > +static void fixup_ref_list(u8 *ref_list, size_t num_valid)
> > > > +{
> > > > + memset(&ref_list[num_valid], 0x20, 32 - num_valid);
> > > > +}
> > > > +
> > > > +static void get_vdec_decode_parameters(struct vdec_h264_slice_inst *inst)
> > > > +{
> > > > + const struct v4l2_ctrl_h264_decode_params *dec_params =
> > > > + get_ctrl_ptr(inst->ctx, V4L2_CID_STATELESS_H264_DECODE_PARAMS);
> > > > + const struct v4l2_ctrl_h264_sps *sps =
> > > > + get_ctrl_ptr(inst->ctx, V4L2_CID_STATELESS_H264_SPS);
> > > > + const struct v4l2_ctrl_h264_pps *pps =
> > > > + get_ctrl_ptr(inst->ctx, V4L2_CID_STATELESS_H264_PPS);
> > > > + const struct v4l2_ctrl_h264_scaling_matrix *scaling_matrix =
> > > > + get_ctrl_ptr(inst->ctx, V4L2_CID_STATELESS_H264_SCALING_MATRIX);
> > > > + struct mtk_h264_dec_slice_param *slice_param = &inst->h264_slice_param;
> > > > + struct v4l2_h264_reflist_builder reflist_builder;
> > > > + enum v4l2_field dpb_fields[V4L2_H264_NUM_DPB_ENTRIES];
> > > > + u8 *p0_reflist = slice_param->decode_params.ref_pic_list_p0;
> > > > + u8 *b0_reflist = slice_param->decode_params.ref_pic_list_b0;
> > > > + u8 *b1_reflist = slice_param->decode_params.ref_pic_list_b1;
> > > > + int i;
> > > > +
> > > > + update_dpb(dec_params, inst->dpb);
> > > > +
> > > > + get_h264_sps_parameters(&slice_param->sps, sps);
> > > > + get_h264_pps_parameters(&slice_param->pps, pps);
> > > > + get_h264_scaling_matrix(&slice_param->scaling_matrix, scaling_matrix);
> > > > + get_h264_decode_parameters(&slice_param->decode_params, dec_params,
> > > > + inst->dpb);
> > > > + get_h264_dpb_list(inst, slice_param);
> > > > +
> > > > + /* Prepare the fields for our reference lists */
> > > > + for (i = 0; i < V4L2_H264_NUM_DPB_ENTRIES; i++)
> > > > + dpb_fields[i] = slice_param->h264_dpb_info[i].field;
> > > > + /* Build the reference lists */
> > > > + v4l2_h264_init_reflist_builder(&reflist_builder, dec_params, sps,
> > > > + inst->dpb);
> > > > + v4l2_h264_build_p_ref_list(&reflist_builder, p0_reflist);
> > > > + v4l2_h264_build_b_ref_lists(&reflist_builder, b0_reflist, b1_reflist);
> > > > + /* Adapt the built lists to the firmware's expectations */
> > > > + fixup_ref_list(p0_reflist, reflist_builder.num_valid);
> > > > + fixup_ref_list(b0_reflist, reflist_builder.num_valid);
> > > > + fixup_ref_list(b1_reflist, reflist_builder.num_valid);
> > > > +
> > > > + memcpy(&inst->vsi_ctx.h264_slice_params, slice_param,
> > > > + sizeof(inst->vsi_ctx.h264_slice_params));
> > > > +}
> > > > +
> > > > +static unsigned int get_mv_buf_size(unsigned int width, unsigned int height)
> > > > +{
> > > > + int unit_size = (width / MB_UNIT_LEN) * (height / MB_UNIT_LEN) + 8;
> > > > +
> > > > + return HW_MB_STORE_SZ * unit_size;
> > > > +}
> > > > +
> > > > +static int allocate_predication_buf(struct vdec_h264_slice_inst *inst)
> > > > +{
> > > > + int err = 0;
> > > > +
> > > > + inst->pred_buf.size = BUF_PREDICTION_SZ;
> > > > + err = mtk_vcodec_mem_alloc(inst->ctx, &inst->pred_buf);
> > > > + if (err) {
> > > > + mtk_vcodec_err(inst, "failed to allocate ppl buf");
> > > > + return err;
> > > > + }
> > > > +
> > > > + inst->vsi_ctx.pred_buf_dma = inst->pred_buf.dma_addr;
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static void free_predication_buf(struct vdec_h264_slice_inst *inst)
> > > > +{
> > > > + struct mtk_vcodec_mem *mem = NULL;
> > > > +
> > > > + mtk_vcodec_debug_enter(inst);
> > > > +
> > > > + inst->vsi_ctx.pred_buf_dma = 0;
> > > > + mem = &inst->pred_buf;
> > > > + if (mem->va)
> > > > + mtk_vcodec_mem_free(inst->ctx, mem);
> > > > +}
> > > > +
> > > > +static int alloc_mv_buf(struct vdec_h264_slice_inst *inst,
> > > > + struct vdec_pic_info *pic)
> > > > +{
> > > > + int i;
> > > > + int err;
> > > > + struct mtk_vcodec_mem *mem = NULL;
> > > > + unsigned int buf_sz = get_mv_buf_size(pic->buf_w, pic->buf_h);
> > > > +
> > > > + mtk_v4l2_debug(3, "size = 0x%lx", buf_sz);
> > > > + for (i = 0; i < H264_MAX_MV_NUM; i++) {
> > > > + mem = &inst->mv_buf[i];
> > > > + if (mem->va)
> > > > + mtk_vcodec_mem_free(inst->ctx, mem);
> > > > + mem->size = buf_sz;
> > > > + err = mtk_vcodec_mem_alloc(inst->ctx, mem);
> > > > + if (err) {
> > > > + mtk_vcodec_err(inst, "failed to allocate mv buf");
> > > > + return err;
> > > > + }
> > > > + inst->vsi_ctx.mv_buf_dma[i] = mem->dma_addr;
> > > > + }
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static void free_mv_buf(struct vdec_h264_slice_inst *inst)
> > > > +{
> > > > + int i;
> > > > + struct mtk_vcodec_mem *mem = NULL;
> > > > +
> > > > + for (i = 0; i < H264_MAX_MV_NUM; i++) {
> > > > + inst->vsi_ctx.mv_buf_dma[i] = 0;
> > > > + mem = &inst->mv_buf[i];
> > > > + if (mem->va)
> > > > + mtk_vcodec_mem_free(inst->ctx, mem);
> > > > + }
> > > > +}
> > > > +
> > > > +static void get_pic_info(struct vdec_h264_slice_inst *inst,
> > > > + struct vdec_pic_info *pic)
> > > > +{
> > > > + struct mtk_vcodec_ctx *ctx = inst->ctx;
> > > > +
> > > > + ctx->picinfo.buf_w = (ctx->picinfo.pic_w + 15) & 0xFFFFFFF0;
> > > > + ctx->picinfo.buf_h = (ctx->picinfo.pic_h + 31) & 0xFFFFFFE0;
> > > > + ctx->picinfo.fb_sz[0] = ctx->picinfo.buf_w * ctx->picinfo.buf_h;
> > > > + ctx->picinfo.fb_sz[1] = ctx->picinfo.fb_sz[0] >> 1;
> > > > + inst->vsi_ctx.dec.cap_num_planes =
> > > > + ctx->q_data[MTK_Q_DATA_DST].fmt->num_planes;
> > > > +
> > > > + pic = &ctx->picinfo;
> > > > + mtk_vcodec_debug(inst, "pic(%d, %d), buf(%d, %d)",
> > > > + ctx->picinfo.pic_w, ctx->picinfo.pic_h,
> > > > + ctx->picinfo.buf_w, ctx->picinfo.buf_h);
> > > > + mtk_vcodec_debug(inst, "Y/C(%d, %d)", ctx->picinfo.fb_sz[0],
> > > > + ctx->picinfo.fb_sz[1]);
> > > > +
> > > > + if ((ctx->last_decoded_picinfo.pic_w != ctx->picinfo.pic_w) ||
> > > > + (ctx->last_decoded_picinfo.pic_h != ctx->picinfo.pic_h)) {
> > > > + inst->vsi_ctx.dec.resolution_changed = true;
> > > > + if ((ctx->last_decoded_picinfo.buf_w != ctx->picinfo.buf_w) ||
> > > > + (ctx->last_decoded_picinfo.buf_h != ctx->picinfo.buf_h))
> > > > + inst->vsi_ctx.dec.realloc_mv_buf = true;
> > > > +
> > > > + mtk_v4l2_debug(1, "ResChg: (%d %d) : old(%d, %d) -> new(%d, %d)",
> > > > + inst->vsi_ctx.dec.resolution_changed,
> > > > + inst->vsi_ctx.dec.realloc_mv_buf,
> > > > + ctx->last_decoded_picinfo.pic_w,
> > > > + ctx->last_decoded_picinfo.pic_h,
> > > > + ctx->picinfo.pic_w, ctx->picinfo.pic_h);
> > > > + }
> > > > +}
> > > > +
> > > > +static void get_crop_info(struct vdec_h264_slice_inst *inst,
> > > > + struct v4l2_rect *cr)
> > > > +{
> > > > + cr->left = inst->vsi_ctx.crop.left;
> > > > + cr->top = inst->vsi_ctx.crop.top;
> > > > + cr->width = inst->vsi_ctx.crop.width;
> > > > + cr->height = inst->vsi_ctx.crop.height;
> > > > +
> > > > + mtk_vcodec_debug(inst, "l=%d, t=%d, w=%d, h=%d",
> > > > + cr->left, cr->top, cr->width, cr->height);
> > > > +}
> > > > +
> > > > +static void get_dpb_size(struct vdec_h264_slice_inst *inst,
> > > > + unsigned int *dpb_sz)
> > > > +{
> > > > + *dpb_sz = inst->vsi_ctx.dec.dpb_sz;
> > > > + mtk_vcodec_debug(inst, "sz=%d", *dpb_sz);
> > > > +}
> > > > +
> > > > +static int vdec_h264_slice_init(struct mtk_vcodec_ctx *ctx)
> > > > +{
> > > > + struct vdec_h264_slice_inst *inst = NULL;
> > > > + int err;
> > > > +
> > > > + inst = kzalloc(sizeof(*inst), GFP_KERNEL);
> > > > + if (!inst)
> > > > + return -ENOMEM;
> > > > +
> > > > + inst->ctx = ctx;
> > > > +
> > > > + inst->vpu.id = SCP_IPI_VDEC_H264;
> > > > + inst->vpu.ctx = ctx;
> > > > +
> > > > + err = vpu_dec_init(&inst->vpu);
> > > > + if (err) {
> > > > + mtk_vcodec_err(inst, "vdec_h264 init err=%d", err);
> > > > + goto error_free_inst;
> > > > + }
> > > > +
> > > > + memcpy(&inst->vsi_ctx, inst->vpu.vsi, sizeof(inst->vsi_ctx));
> > > > + inst->vsi_ctx.dec.resolution_changed = true;
> > > > + inst->vsi_ctx.dec.realloc_mv_buf = true;
> > > > +
> > > > + err = allocate_predication_buf(inst);
> > > > + if (err)
> > > > + goto error_deinit;
> > > > +
> > > > + mtk_vcodec_debug(inst, "struct size = %d,%d,%d,%d\n",
> > > > + sizeof(struct mtk_h264_sps_param),
> > > > + sizeof(struct mtk_h264_pps_param),
> > > > + sizeof(struct mtk_h264_dec_slice_param),
> > > > + sizeof(struct mtk_h264_dpb_info));
> > > > +
> > > > + mtk_vcodec_debug(inst, "H264 Instance >> %p", inst);
> > > > +
> > > > + ctx->drv_handle = inst;
> > > > + return 0;
> > > > +
> > > > +error_deinit:
> > > > + vpu_dec_deinit(&inst->vpu);
> > > > +
> > > > +error_free_inst:
> > > > + kfree(inst);
> > > > + return err;
> > > > +}
> > > > +
> > > > +static void vdec_h264_slice_deinit(void *h_vdec)
> > > > +{
> > > > + struct vdec_h264_slice_inst *inst =
> > > > + (struct vdec_h264_slice_inst *)h_vdec;
> > > > +
> > > > + mtk_vcodec_debug_enter(inst);
> > > > +
> > > > + vpu_dec_deinit(&inst->vpu);
> > > > + free_predication_buf(inst);
> > > > + free_mv_buf(inst);
> > > > +
> > > > + kfree(inst);
> > > > +}
> > > > +
> > > > +static int find_start_code(unsigned char *data, unsigned int data_sz)
> > > > +{
> > > > + if (data_sz > 3 && data[0] == 0 && data[1] == 0 && data[2] == 1)
> > > > + return 3;
> > > > +
> > > > + if (data_sz > 4 && data[0] == 0 && data[1] == 0 && data[2] == 0 &&
> > > > + data[3] == 1)
> > > > + return 4;
> > > > +
> > > > + return -1;
> > > > +}
> > > > +
> > > > +static int vdec_h264_slice_decode(void *h_vdec, struct mtk_vcodec_mem *bs,
> > > > + struct vdec_fb *fb, bool *res_chg)
> > > > +{
> > > > + struct vdec_h264_slice_inst *inst =
> > > > + (struct vdec_h264_slice_inst *)h_vdec;
> > > > + struct vdec_vpu_inst *vpu = &inst->vpu;
> > > > + struct mtk_video_dec_buf *src_buf_info;
> > > > + int nal_start_idx = 0, err = 0;
> > > > + uint32_t nal_type, data[2];
> > > > + unsigned char *buf;
> > > > + uint64_t y_fb_dma;
> > > > + uint64_t c_fb_dma;
> > > > +
> > > > + mtk_vcodec_debug(inst, "+ [%d] FB y_dma=%llx c_dma=%llx va=%p",
> > > > + ++inst->num_nalu, y_fb_dma, c_fb_dma, fb);
> > > > +
> > > > + /* bs NULL means flush decoder */
> > > > + if (bs == NULL)
> > > > + return vpu_dec_reset(vpu);
> > > > +
> > > > + src_buf_info = container_of(bs, struct mtk_video_dec_buf, bs_buffer);
> > > > +
> > > > + y_fb_dma = fb ? (u64)fb->base_y.dma_addr : 0;
> > > > + c_fb_dma = fb ? (u64)fb->base_c.dma_addr : 0;
> > > > +
> > > > + buf = (unsigned char *)bs->va;
> > >
> > > I can be completely wrong, but it would seem here
> > > is where the CPU mapping is used.
> >
> > I think you're right. :)
> >
> > >
> > > > + nal_start_idx = find_start_code(buf, bs->size);
> > > > + if (nal_start_idx < 0)
> > > > + goto err_free_fb_out;
> > > > +
> > > > + data[0] = bs->size;
> > > > + data[1] = buf[nal_start_idx];
> > > > + nal_type = NAL_TYPE(buf[nal_start_idx]);
> > >
> > > Which seems to be used to parse the NAL type. But shouldn't
> > > you expect here VLC NALUs only?
> > >
> > > I.e. you only get IDR or non-IDR frames, marked with
> > > V4L2_H264_DECODE_PARAM_FLAG_IDR_PIC.
> >
> > Yep, that's true. And as a matter of fact I can remove `nal_type` (and
> > the test using it below) and the driver is just as happy.
> >
> > >
> > > > + mtk_vcodec_debug(inst, "\n + NALU[%d] type %d +\n", inst->num_nalu,
> > > > + nal_type);
> > > > +
> > > > + inst->vsi_ctx.dec.bs_dma = (uint64_t)bs->dma_addr;
> > > > + inst->vsi_ctx.dec.y_fb_dma = y_fb_dma;
> > > > + inst->vsi_ctx.dec.c_fb_dma = c_fb_dma;
> > > > + inst->vsi_ctx.dec.vdec_fb_va = (u64)(uintptr_t)fb;
> > > > +
> > > > + get_vdec_decode_parameters(inst);
> > > > + *res_chg = inst->vsi_ctx.dec.resolution_changed;
> > > > + if (*res_chg) {
> > > > + mtk_vcodec_debug(inst, "- resolution changed -");
> > > > + if (inst->vsi_ctx.dec.realloc_mv_buf) {
> > > > + err = alloc_mv_buf(inst, &(inst->ctx->picinfo));
> > > > + inst->vsi_ctx.dec.realloc_mv_buf = false;
> > > > + if (err)
> > > > + goto err_free_fb_out;
> > > > + }
> > > > + *res_chg = false;
> > > > + }
> > > > +
> > > > + memcpy(inst->vpu.vsi, &inst->vsi_ctx, sizeof(inst->vsi_ctx));
> > > > + err = vpu_dec_start(vpu, data, 2);
> > >
> > > Then it seems this 2-bytes are passed to the firmware. Maybe you
> > > could test if that can be derived without the CPU mapping.
> > > That would allow you to set DMA_ATTR_NO_KERNEL_MAPPING.
> >
> > This one is a bit trickier. It seems the NAL type is passed as part of
> > the decode request to the firmware. Which should be absolutely not
> > needed since the firmware can check this from the buffer itself. Just
> > for fun I have tried setting this parameter unconditionally to 0x1
> > (non-IDR picture) and all I get is green frames with seemingly random
> > garbage. If I set it to 0x5 (IDR picture) I also get green frames with
> > a different kind of garbage, and once every while a properly rendered
> > frame (presumably when it is *really* an IDR frame).
> >
> > So, mmm, I'm afraid we cannot decode properly without this information
> > and thus without the mapping, unless Yunfei can tell us of a way to
> > achieve this. Yunfei, do you have any idea?
> >
>
> Sorry, I wasn't clear with my suggestion. I didn't want to imply to avoid
> passing the firmware the information, just to stop deriving it from the buffers.
>
> Along these lines:
>
> data[0] = bs->size;
> - data[1] = buf[nal_start_idx];
> - nal_type = NAL_TYPE(buf[nal_start_idx]);
> + data[1] = nal_type = (dec_param->flags &
> V4L2_H264_DECODE_PARAM_FLAG_IDR_PIC) ?
> + NAL_IDR_SLICE : NAL_NON_IDR_SLICE;
>
> (or slice type as Nicolas was suggesting)
Ahhh I see. Great idea!
When trying it, I realized that this data[1] byte also contains the
nal_ref_idc on top of the NAL type. Not including it in the value
would result in the decoder misbehaving. But fortunately that
parameter is also passed by user-space, so using that and the IDR_PIC
flag I can reconstruct the information accurately, and the decoder is
happy. Nice!
This means I can also remove the CPU mappings done in the previous
patch. I suspect there is room for further improvement since I see the
stateful part of the driver does the same thing (and submits the same
information to the firmware) - only here we cannot get that
information from userspace-provided parameters.
But at least for the stateless part we don't need the CPU mapping at
all, so I've removed it.
>
> This should allow you to not allocate your buffers coherently,
> as you are doing now (i.e. not requiring a CPU mapping).
>
> I don't know what would be the performance gains in your platform,
> but they might be worth it (note that this depends on the platform
> support for non-coherent DMA mappings).
>
> In any case, this is just a suggestion, mostly because a CPU mapping
> means the kernel is parsing the buffers, which is a bit unexpected.
>
> Regards,
> Ezequiel
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