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[209.85.208.178]) by smtp.gmail.com with ESMTPSA id y18sm3235915lfl.131.2021.03.16.20.13.56 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 16 Mar 2021 20:13:57 -0700 (PDT) Received: by mail-lj1-f178.google.com with SMTP id 16so1347030ljc.11 for ; Tue, 16 Mar 2021 20:13:56 -0700 (PDT) X-Received: by 2002:a2e:8881:: with SMTP id k1mr1036481lji.441.1615950835916; Tue, 16 Mar 2021 20:13:55 -0700 (PDT) MIME-Version: 1.0 References: <20210226100148.1663389-1-acourbot@chromium.org> <20210226100148.1663389-6-acourbot@chromium.org> In-Reply-To: From: Alexandre Courbot Date: Wed, 17 Mar 2021 12:13:44 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v3 05/15] media: mtk-vcodec: vdec: support stateless API To: Ezequiel Garcia Cc: Tiffany Lin , Andrew-CT Chen , Rob Herring , Yunfei Dong , Mauro Carvalho Chehab , Hans Verkuil , linux-media , Linux Kernel Mailing List , "moderated list:ARM/Mediatek SoC support" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Tue, Mar 16, 2021 at 6:45 AM Ezequiel Garcia wrote: > > Hi Alexandre, > > On Mon, 15 Mar 2021 at 08:28, Alexandre Courbot wrote: > > > > Hi Ezequiel, thanks for the feedback! > > > > On Thu, Mar 4, 2021 at 6:30 AM Ezequiel Garcia > > wrote: > > > > > > Hello Alex, > > > > > > Thanks for the patch. > > > > > > On Fri, 26 Feb 2021 at 07:06, Alexandre Courbot wrote: > > > > > > > > From: Yunfei Dong > > > > > > > > Support the stateless codec API that will be used by MT8183. > > > > > > > > Signed-off-by: Yunfei Dong > > > > [acourbot: refactor, cleanup and split] > > > > Co-developed-by: Alexandre Courbot > > > > Signed-off-by: Alexandre Courbot > > > > --- > > > > drivers/media/platform/mtk-vcodec/Makefile | 1 + > > > > .../platform/mtk-vcodec/mtk_vcodec_dec.c | 66 ++- > > > > .../platform/mtk-vcodec/mtk_vcodec_dec.h | 9 +- > > > > .../mtk-vcodec/mtk_vcodec_dec_stateless.c | 427 ++++++++++++++++++ > > > > .../platform/mtk-vcodec/mtk_vcodec_drv.h | 3 + > > > > 5 files changed, 503 insertions(+), 3 deletions(-) > > > > create mode 100644 drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_stateless.c > > > > > > > [..] > > > > > > > + > > > > +static const struct mtk_stateless_control mtk_stateless_controls[] = { > > > > + { > > > > + .cfg = { > > > > + .id = V4L2_CID_STATELESS_H264_SPS, > > > > + }, > > > > + .codec_type = V4L2_PIX_FMT_H264_SLICE, > > > > + .needed_in_request = true, > > > > > > This "needed_in_request" is not really required, as controls > > > are not volatile, and their value is stored per-context (per-fd). > > > > > > It's perfectly valid for an application to pass the SPS control > > > at the beginning of the sequence, and then omit it > > > in further requests. > > > > If I understand how v4l2_ctrl_request_hdl_ctrl_find() works with > > requests, this boolean only checks that the control has been provided > > at least once, and not that it is provided with every request. Without > > it we could send a frame to the firmware without e.g. setting an SPS, > > which would be a problem. > > > > As Nicolas points out, in V4L2 controls have an initial value, > so no control can be unset. I see. So I guess the expectation is that failure will occur later as the firmware reports it cannot decode properly (or returns a corrupted frame). Thanks for the precision. > > > > > > > > + }, > > > > + { > > > > + .cfg = { > > > > + .id = V4L2_CID_STATELESS_H264_PPS, > > > > + }, > > > > + .codec_type = V4L2_PIX_FMT_H264_SLICE, > > > > + .needed_in_request = true, > > > > + }, > > > > + { > > > > + .cfg = { > > > > + .id = V4L2_CID_STATELESS_H264_SCALING_MATRIX, > > > > + }, > > > > + .codec_type = V4L2_PIX_FMT_H264_SLICE, > > > > + .needed_in_request = true, > > > > + }, > > > > + { > > > > + .cfg = { > > > > + .id = V4L2_CID_STATELESS_H264_DECODE_PARAMS, > > > > + }, > > > > + .codec_type = V4L2_PIX_FMT_H264_SLICE, > > > > + .needed_in_request = true, > > > > + }, > > > > + { > > > > + .cfg = { > > > > + .id = V4L2_CID_MPEG_VIDEO_H264_PROFILE, > > > > + .def = V4L2_MPEG_VIDEO_H264_PROFILE_MAIN, > > > > + .max = V4L2_MPEG_VIDEO_H264_PROFILE_HIGH, > > > > + .menu_skip_mask = > > > > + BIT(V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE) | > > > > + BIT(V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED), > > > > + }, > > > > + .codec_type = V4L2_PIX_FMT_H264_SLICE, > > > > + }, > > > > + { > > > > + .cfg = { > > > > + .id = V4L2_CID_STATELESS_H264_DECODE_MODE, > > > > + .min = V4L2_STATELESS_H264_DECODE_MODE_FRAME_BASED, > > > > + .def = V4L2_STATELESS_H264_DECODE_MODE_FRAME_BASED, > > > > + .max = V4L2_STATELESS_H264_DECODE_MODE_FRAME_BASED, > > > > + }, > > > > + .codec_type = V4L2_PIX_FMT_H264_SLICE, > > > > + }, > > > > +}; > > > > > > Applications also need to know which V4L2_CID_STATELESS_H264_START_CODE > > > the driver supports. From a next patch, this case seems to be > > > V4L2_STATELESS_H264_START_CODE_ANNEX_B. > > > > Indeed - I've added the control, thanks for catching this! > > > > > > > > > +#define NUM_CTRLS ARRAY_SIZE(mtk_stateless_controls) > > > > + > > > > +static const struct mtk_video_fmt mtk_video_formats[] = { > > > > + { > > > > + .fourcc = V4L2_PIX_FMT_H264_SLICE, > > > > + .type = MTK_FMT_DEC, > > > > + .num_planes = 1, > > > > + }, > > > > + { > > > > + .fourcc = V4L2_PIX_FMT_MM21, > > > > + .type = MTK_FMT_FRAME, > > > > + .num_planes = 2, > > > > + }, > > > > +}; > > > > +#define NUM_FORMATS ARRAY_SIZE(mtk_video_formats) > > > > +#define DEFAULT_OUT_FMT_IDX 0 > > > > +#define DEFAULT_CAP_FMT_IDX 1 > > > > + > > > > +static const struct mtk_codec_framesizes mtk_vdec_framesizes[] = { > > > > + { > > > > + .fourcc = V4L2_PIX_FMT_H264_SLICE, > > > > + .stepwise = { > > > > + MTK_VDEC_MIN_W, MTK_VDEC_MAX_W, 16, > > > > + MTK_VDEC_MIN_H, MTK_VDEC_MAX_H, 16, > > > > + }, > > > > + }, > > > > +}; > > > > + > > > > +#define NUM_SUPPORTED_FRAMESIZE ARRAY_SIZE(mtk_vdec_framesizes) > > > > + > > > > +static void mtk_vdec_stateless_set_dst_payload(struct mtk_vcodec_ctx *ctx, > > > > + struct vdec_fb *fb) > > > > +{ > > > > + struct mtk_video_dec_buf *vdec_frame_buf = > > > > + container_of(fb, struct mtk_video_dec_buf, frame_buffer); > > > > + struct vb2_v4l2_buffer *vb = &vdec_frame_buf->m2m_buf.vb; > > > > + unsigned int cap_y_size = ctx->q_data[MTK_Q_DATA_DST].sizeimage[0]; > > > > + > > > > + vb2_set_plane_payload(&vb->vb2_buf, 0, cap_y_size); > > > > + if (ctx->q_data[MTK_Q_DATA_DST].fmt->num_planes == 2) { > > > > + unsigned int cap_c_size = > > > > + ctx->q_data[MTK_Q_DATA_DST].sizeimage[1]; > > > > + > > > > + vb2_set_plane_payload(&vb->vb2_buf, 1, cap_c_size); > > > > + } > > > > +} > > > > + > > > > +static struct vdec_fb *vdec_get_cap_buffer(struct mtk_vcodec_ctx *ctx, > > > > + struct vb2_v4l2_buffer *vb2_v4l2) > > > > +{ > > > > + struct mtk_video_dec_buf *framebuf = > > > > + container_of(vb2_v4l2, struct mtk_video_dec_buf, m2m_buf.vb); > > > > + struct vdec_fb *pfb = &framebuf->frame_buffer; > > > > + struct vb2_buffer *dst_buf = &vb2_v4l2->vb2_buf; > > > > + > > > > + pfb = &framebuf->frame_buffer; > > > > + pfb->base_y.va = vb2_plane_vaddr(dst_buf, 0); > > > > > > Are you sure you need a CPU mapping? It seems strange. > > > I'll comment some more on the next patch(es). > > > > I'll answer on the next patch since this is where that mapping is being used. > > > > > > > > > + pfb->base_y.dma_addr = vb2_dma_contig_plane_dma_addr(dst_buf, 0); > > > > + pfb->base_y.size = ctx->q_data[MTK_Q_DATA_DST].sizeimage[0]; > > > > + > > > > + if (ctx->q_data[MTK_Q_DATA_DST].fmt->num_planes == 2) { > > > > + pfb->base_c.va = vb2_plane_vaddr(dst_buf, 1); > > > > + pfb->base_c.dma_addr = > > > > + vb2_dma_contig_plane_dma_addr(dst_buf, 1); > > > > + pfb->base_c.size = ctx->q_data[MTK_Q_DATA_DST].sizeimage[1]; > > > > + } > > > > + mtk_v4l2_debug(1, > > > > + "id=%d Framebuf pfb=%p VA=%p Y_DMA=%pad C_DMA=%pad Size=%zx frame_count = %d", > > > > + dst_buf->index, pfb, > > > > + pfb->base_y.va, &pfb->base_y.dma_addr, > > > > + &pfb->base_c.dma_addr, pfb->base_y.size, > > > > + ctx->decoded_frame_cnt); > > > > + > > > > + return pfb; > > > > +} > > > > + > > > > +static void vb2ops_vdec_buf_request_complete(struct vb2_buffer *vb) > > > > +{ > > > > + struct mtk_vcodec_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue); > > > > + > > > > + v4l2_ctrl_request_complete(vb->req_obj.req, &ctx->ctrl_hdl); > > > > +} > > > > + > > > > +static int fops_media_request_validate(struct media_request *mreq) > > > > +{ > > > > + const unsigned int buffer_cnt = vb2_request_buffer_cnt(mreq); > > > > + struct mtk_vcodec_ctx *ctx = NULL; > > > > + struct media_request_object *req_obj; > > > > + struct v4l2_ctrl_handler *parent_hdl, *hdl; > > > > + struct v4l2_ctrl *ctrl; > > > > + unsigned int i; > > > > + > > > > + switch (buffer_cnt) { > > > > + case 1: > > > > + /* We expect exactly one buffer with the request */ > > > > + break; > > > > + case 0: > > > > + mtk_v4l2_err("No buffer provided with the request"); > > > > + return -ENOENT; > > > > + default: > > > > + mtk_v4l2_err("Too many buffers (%d) provided with the request", > > > > + buffer_cnt); > > > > + return -EINVAL; > > > > + } > > > > + > > > > + list_for_each_entry(req_obj, &mreq->objects, list) { > > > > + struct vb2_buffer *vb; > > > > + > > > > + if (vb2_request_object_is_buffer(req_obj)) { > > > > + vb = container_of(req_obj, struct vb2_buffer, req_obj); > > > > + ctx = vb2_get_drv_priv(vb->vb2_queue); > > > > + break; > > > > + } > > > > + } > > > > + > > > > + if (!ctx) { > > > > + mtk_v4l2_err("Cannot find buffer for request"); > > > > + return -ENOENT; > > > > + } > > > > + > > > > + parent_hdl = &ctx->ctrl_hdl; > > > > + > > > > + hdl = v4l2_ctrl_request_hdl_find(mreq, parent_hdl); > > > > + if (!hdl) { > > > > + mtk_v4l2_err("Cannot find control handler for request\n"); > > > > + return -ENOENT; > > > > + } > > > > + > > > > + for (i = 0; i < NUM_CTRLS; i++) { > > > > + if (mtk_stateless_controls[i].codec_type != ctx->current_codec) > > > > + continue; > > > > + if (!mtk_stateless_controls[i].needed_in_request) > > > > + continue; > > > > + > > > > + ctrl = v4l2_ctrl_request_hdl_ctrl_find(hdl, > > > > + mtk_stateless_controls[i].cfg.id); > > > > + if (!ctrl) { > > > > + mtk_v4l2_err("Missing required codec control\n"); > > > > + return -ENOENT; > > > > + } > > > > + } > > > > + > > > > + v4l2_ctrl_request_hdl_put(hdl); > > > > + > > > > + return vb2_request_validate(mreq); > > > > +} > > > > + > > > > +static void mtk_vdec_worker(struct work_struct *work) > > > > +{ > > > > + struct mtk_vcodec_ctx *ctx = > > > > + container_of(work, struct mtk_vcodec_ctx, decode_work); > > > > + struct mtk_vcodec_dev *dev = ctx->dev; > > > > + struct vb2_v4l2_buffer *vb2_v4l2_src, *vb2_v4l2_dst; > > > > + struct vb2_buffer *vb2_src; > > > > + struct mtk_vcodec_mem *bs_src; > > > > + struct mtk_video_dec_buf *dec_buf_src; > > > > + struct media_request *src_buf_req; > > > > + struct vdec_fb *dst_buf; > > > > + bool res_chg = false; > > > > + int ret; > > > > + > > > > + vb2_v4l2_src = v4l2_m2m_next_src_buf(ctx->m2m_ctx); > > > > + if (vb2_v4l2_src == NULL) { > > > > + v4l2_m2m_job_finish(dev->m2m_dev_dec, ctx->m2m_ctx); > > > > + mtk_v4l2_debug(1, "[%d] no available source buffer", ctx->id); > > > > + return; > > > > + } > > > > + > > > > + vb2_v4l2_dst = v4l2_m2m_next_dst_buf(ctx->m2m_ctx); > > > > + if (vb2_v4l2_dst == NULL) { > > > > + v4l2_m2m_job_finish(dev->m2m_dev_dec, ctx->m2m_ctx); > > > > + mtk_v4l2_debug(1, "[%d] no available destination buffer", ctx->id); > > > > + return; > > > > + } > > > > + > > > > + vb2_src = &vb2_v4l2_src->vb2_buf; > > > > + dec_buf_src = container_of(vb2_v4l2_src, struct mtk_video_dec_buf, > > > > + m2m_buf.vb); > > > > + bs_src = &dec_buf_src->bs_buffer; > > > > + > > > > + mtk_v4l2_debug(3, "[%d] (%d) id=%d, vb=%p buf_info = %p", > > > > + ctx->id, src_buf->vb2_queue->type, > > > > + src_buf->index, src_buf, src_buf_info); > > > > + > > > > + bs_src->va = vb2_plane_vaddr(vb2_src, 0); > > > > + bs_src->dma_addr = vb2_dma_contig_plane_dma_addr(vb2_src, 0); > > > > + bs_src->size = (size_t)vb2_src->planes[0].bytesused; > > > > + if (!bs_src->va) { > > > > + v4l2_m2m_job_finish(dev->m2m_dev_dec, ctx->m2m_ctx); > > > > + mtk_v4l2_err("[%d] id=%d source buffer is NULL", ctx->id, > > > > + vb2_src->index); > > > > + return; > > > > + } > > > > + > > > > + mtk_v4l2_debug(3, "[%d] Bitstream VA=%p DMA=%pad Size=%zx vb=%p", > > > > + ctx->id, buf->va, &buf->dma_addr, buf->size, src_buf); > > > > + /* Apply request controls. */ > > > > + src_buf_req = vb2_src->req_obj.req; > > > > + if (src_buf_req) > > > > + v4l2_ctrl_request_setup(src_buf_req, &ctx->ctrl_hdl); > > > > + else > > > > + mtk_v4l2_err("vb2 buffer media request is NULL"); > > > > + > > > > + dst_buf = vdec_get_cap_buffer(ctx, vb2_v4l2_dst); > > > > + v4l2_m2m_buf_copy_metadata(vb2_v4l2_src, vb2_v4l2_dst, true); > > > > + ret = vdec_if_decode(ctx, bs_src, dst_buf, &res_chg); > > > > + if (ret) { > > > > + mtk_v4l2_err( > > > > + " <===[%d], src_buf[%d] sz=0x%zx pts=%llu vdec_if_decode() ret=%d res_chg=%d===>", > > > > + ctx->id, vb2_src->index, bs_src->size, > > > > + vb2_src->timestamp, ret, res_chg); > > > > + if (ret == -EIO) { > > > > + mutex_lock(&ctx->lock); > > > > + dec_buf_src->error = true; > > > > + mutex_unlock(&ctx->lock); > > > > + } > > > > + } > > > > + > > > > + mtk_vdec_stateless_set_dst_payload(ctx, dst_buf); > > > > + > > > > + v4l2_m2m_buf_done_and_job_finish(dev->m2m_dev_dec, ctx->m2m_ctx, > > > > + ret ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE); > > > > + > > > > + v4l2_ctrl_request_complete(src_buf_req, &ctx->ctrl_hdl); > > > > +} > > > > + > > > > +static void vb2ops_vdec_stateless_buf_queue(struct vb2_buffer *vb) > > > > +{ > > > > + struct mtk_vcodec_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue); > > > > + struct vb2_v4l2_buffer *vb2_v4l2 = to_vb2_v4l2_buffer(vb); > > > > + > > > > + mtk_v4l2_debug(3, "[%d] (%d) id=%d, vb=%p", > > > > + ctx->id, vb->vb2_queue->type, > > > > + vb->index, vb); > > > > + > > > > + mutex_lock(&ctx->lock); > > > > + v4l2_m2m_buf_queue(ctx->m2m_ctx, vb2_v4l2); > > > > + mutex_unlock(&ctx->lock); > > > > + if (vb->vb2_queue->type != V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) > > > > + return; > > > > + > > > > + mtk_v4l2_debug(3, "(%d) id=%d, bs=%p", > > > > + vb->vb2_queue->type, vb->index, src_buf); > > > > + > > > > + /* If an OUTPUT buffer, we may need to update the state */ > > > > + if (ctx->state == MTK_STATE_INIT) { > > > > + ctx->state = MTK_STATE_HEADER; > > > > + mtk_v4l2_debug(1, "Init driver from init to header."); > > > > > > This state thing seems just something to make the rest > > > of the stateful-based driver happy, right? > > > > Correct - if anything we should either use more of the state here > > (i.e. set the error state when relevant) or move the state entirely in > > the stateful part of the driver. > > > > > > > > Makes me wonder a bit if just splitting the stateless part to its > > > own driver, wouldn't make your maintenance easier. > > > > > > What's the motivation for sharing the driver? > > > > Technically you could do it both ways. Separating the driver would > > result in some boilerplate code and buffer-management structs > > duplication (unless we keep the shared part under another module - but > > in this case we are basically in the same situation as now). Also > > despite using different userspace-facing ABIs, MT8173 and MT8183 > > follow a similar architecture and a similar firmware interface. > > Considering these similarities it seems simpler from an architectural > > point of view to have all the Mediatek codec support under the same > > driver. It also probably results in less code. > > > > That being said, the split can probably be improved as you pointed out > > with this state variable. But the current split is not too bad IMHO, > > at least not worse than how the code was originally. > > > > > > > > > + } else { > > > > + mtk_v4l2_debug(3, "[%d] already init driver %d", > > > > + ctx->id, ctx->state); > > > > + } > > > > +} > > > > + > > > > +static int mtk_vdec_flush_decoder(struct mtk_vcodec_ctx *ctx) > > > > +{ > > > > + bool res_chg; > > > > + > > > > + return vdec_if_decode(ctx, NULL, NULL, &res_chg); > > > > +} > > > > + > > > > +static const struct v4l2_ctrl_ops mtk_vcodec_dec_ctrl_ops = { > > > > + .g_volatile_ctrl = mtk_vdec_g_v_ctrl, > > > > +}; > > > > + > > > > +static int mtk_vcodec_dec_ctrls_setup(struct mtk_vcodec_ctx *ctx) > > > > +{ > > > > + struct v4l2_ctrl *ctrl; > > > > + unsigned int i; > > > > + > > > > + v4l2_ctrl_handler_init(&ctx->ctrl_hdl, NUM_CTRLS); > > > > + if (ctx->ctrl_hdl.error) { > > > > + mtk_v4l2_err("v4l2_ctrl_handler_init failed\n"); > > > > + return ctx->ctrl_hdl.error; > > > > + } > > > > + > > > > + ctrl = v4l2_ctrl_new_std(&ctx->ctrl_hdl, > > > > + &mtk_vcodec_dec_ctrl_ops, > > > > + V4L2_CID_MIN_BUFFERS_FOR_CAPTURE, > > > > + 0, 32, 1, 1); > > > > + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE; > > > > > > Hm, this volatile control for MIN_BUFFERS_FOR_CAPTURE seems > > > to return the DPB size. However, isn't this something userspace already knows? > > > > True, but that's also a control the driver is supposed to provide per > > the spec IIUC. > > > > I don't see the specification requiring this control. TBH, I'd just drop it > and if needed fix the application to support this as an optional > control. > > In any case, stateless devices should just need 1 output and 1 capture buffer. Mmm, you're correct indeed, and checking with our user-space it does not rely on this control for stateless codecs. Moving this control to the stateful part of the driver. > > You might dislike this redundancy, note that you can also get the minimum > required buffers through VIDIOC_REQBUFS, where the count > v4l2_requestbuffers.field is returned back to userspace with the > number of allocated buffers. > > If you request just 1 buffer, and your driver needed 3, you should > get a 3 there (vb2_ops.queue_setup takes care of that). > > Thanks, > Ezequiel