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[209.85.167.175]) by smtp.gmail.com with ESMTPSA id q128sm9995591oia.4.2019.01.24.00.44.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Jan 2019 00:44:32 -0800 (PST) Received: by mail-oi1-f175.google.com with SMTP id j21so4196226oii.8 for ; Thu, 24 Jan 2019 00:44:31 -0800 (PST) X-Received: by 2002:aca:dec1:: with SMTP id v184mr521804oig.217.1548319471364; Thu, 24 Jan 2019 00:44:31 -0800 (PST) MIME-Version: 1.0 References: <20190117162008.25217-1-stanimir.varbanov@linaro.org> <20190117162008.25217-11-stanimir.varbanov@linaro.org> In-Reply-To: <20190117162008.25217-11-stanimir.varbanov@linaro.org> From: Alexandre Courbot Date: Thu, 24 Jan 2019 17:44:20 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 10/10] venus: dec: make decoder compliant with stateful codec API To: Stanimir Varbanov Cc: Linux Media Mailing List , Mauro Carvalho Chehab , Hans Verkuil , LKML , linux-arm-msm@vger.kernel.org, Vikash Garodia , Tomasz Figa , Malathi Gottam Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 18, 2019 at 1:21 AM Stanimir Varbanov wrote: > > This refactored code for start/stop streaming vb2 operations and s/refactored/refactors? > adds a state machine handling similar to the one in stateful codec > API documentation. One major change is that now the HFI session is > started on STREAMON(OUTPUT) and stopped on REQBUF(OUTPUT,count=0), > during that time streamoff(cap,out) just flush buffers but doesn't streamoff(cap,out) should probably be in capitals for consistency. > stop the session. The other major change is that now the capture > and output queues are completely separated. > > Signed-off-by: Stanimir Varbanov > --- > drivers/media/platform/qcom/venus/core.h | 20 +- > drivers/media/platform/qcom/venus/helpers.c | 23 +- > drivers/media/platform/qcom/venus/helpers.h | 5 + > drivers/media/platform/qcom/venus/vdec.c | 449 ++++++++++++++++---- > 4 files changed, 389 insertions(+), 108 deletions(-) > > diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h > index 79c7e816c706..5a133c203455 100644 > --- a/drivers/media/platform/qcom/venus/core.h > +++ b/drivers/media/platform/qcom/venus/core.h > @@ -218,6 +218,15 @@ struct venus_buffer { > > #define to_venus_buffer(ptr) container_of(ptr, struct venus_buffer, vb) > > +#define DEC_STATE_UNINIT 0 Not sure about "uninit", DEC_STATE_DEINIT may be more explicit here? > +#define DEC_STATE_INIT 1 > +#define DEC_STATE_CAPTURE_SETUP 2 > +#define DEC_STATE_STOPPED 3 > +#define DEC_STATE_SEEK 4 > +#define DEC_STATE_DRAIN 5 > +#define DEC_STATE_DECODING 6 > +#define DEC_STATE_DRC 7 How about defining these as an enum, for better type safety? I'd also prefix with VENUS_ to avoid possible (if unlikely) name collisions. > + > /** > * struct venus_inst - holds per instance paramerters > * > @@ -241,6 +250,10 @@ struct venus_buffer { > * @colorspace: current color space > * @quantization: current quantization > * @xfer_func: current xfer function > + * @codec_state: current codec API state (see DEC/ENC_STATE_) > + * @reconf_wait: wait queue for resolution change event > + * @ten_bits: does new stream is 10bits depth "is new stream 10 bits deep" maybe? > + * @buf_count: used to count number number of buffers (reqbuf(0)) "number" written twice here. > * @fps: holds current FPS > * @timeperframe: holds current time per frame structure > * @fmt_out: a reference to output format structure > @@ -255,8 +268,6 @@ struct venus_buffer { > * @opb_buftype: output picture buffer type > * @opb_fmt: output picture buffer raw format > * @reconfig: a flag raised by decoder when the stream resolution changed > - * @reconfig_width: holds the new width > - * @reconfig_height: holds the new height > * @hfi_codec: current codec for this instance in HFI space > * @sequence_cap: a sequence counter for capture queue > * @sequence_out: a sequence counter for output queue > @@ -296,6 +307,9 @@ struct venus_inst { > u8 ycbcr_enc; > u8 quantization; > u8 xfer_func; > + unsigned int codec_state; As mentioned above, with an enum the type of this member would make it obvious which values it can accept. > + wait_queue_head_t reconf_wait; > + int buf_count; > u64 fps; > struct v4l2_fract timeperframe; > const struct venus_format *fmt_out; > @@ -310,8 +324,6 @@ struct venus_inst { > u32 opb_buftype; > u32 opb_fmt; > bool reconfig; > - u32 reconfig_width; > - u32 reconfig_height; > u32 hfi_codec; > u32 sequence_cap; > u32 sequence_out; > diff --git a/drivers/media/platform/qcom/venus/helpers.c b/drivers/media/platform/qcom/venus/helpers.c > index 637ce7b82d94..25d8cceccae4 100644 > --- a/drivers/media/platform/qcom/venus/helpers.c > +++ b/drivers/media/platform/qcom/venus/helpers.c > @@ -1030,16 +1030,15 @@ void venus_helper_vb2_buf_queue(struct vb2_buffer *vb) > > v4l2_m2m_buf_queue(m2m_ctx, vbuf); > > - if (!(inst->streamon_out & inst->streamon_cap)) > - goto unlock; > - > - ret = is_buf_refed(inst, vbuf); > - if (ret) > - goto unlock; > + if (IS_OUT(vb->vb2_queue, inst) || IS_CAP(vb->vb2_queue, inst)) { > + ret = is_buf_refed(inst, vbuf); > + if (ret) > + goto unlock; > > - ret = session_process_buf(inst, vbuf); > - if (ret) > - return_buf_error(inst, vbuf); > + ret = session_process_buf(inst, vbuf); > + if (ret) > + return_buf_error(inst, vbuf); > + } > > unlock: > mutex_unlock(&inst->lock); > @@ -1155,14 +1154,8 @@ int venus_helper_vb2_start_streaming(struct venus_inst *inst) > if (ret) > goto err_unload_res; > > - ret = venus_helper_queue_dpb_bufs(inst); > - if (ret) > - goto err_session_stop; > - > return 0; > > -err_session_stop: > - hfi_session_stop(inst); > err_unload_res: > hfi_session_unload_res(inst); > err_unreg_bufs: > diff --git a/drivers/media/platform/qcom/venus/helpers.h b/drivers/media/platform/qcom/venus/helpers.h > index 2ec1c1a8b416..3b46139b5ee1 100644 > --- a/drivers/media/platform/qcom/venus/helpers.h > +++ b/drivers/media/platform/qcom/venus/helpers.h > @@ -17,6 +17,11 @@ > > #include > > +#define IS_OUT(q, inst) (inst->streamon_out && \ > + q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) > +#define IS_CAP(q, inst) (inst->streamon_cap && \ > + q->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) These macro names are pretty generic and we are at risk of a name collision in the future. Also the name conveys the idea that the macro will check for the buffer type only ; yet IIUC we also check that the corresponding queue is streaming? Maybe something like VENUS_BUF_OUT_READY() would be more meaningful. > + > struct venus_inst; > struct venus_core; > > diff --git a/drivers/media/platform/qcom/venus/vdec.c b/drivers/media/platform/qcom/venus/vdec.c > index 7a9370df7515..306e0f7d3337 100644 > --- a/drivers/media/platform/qcom/venus/vdec.c > +++ b/drivers/media/platform/qcom/venus/vdec.c > @@ -201,28 +201,18 @@ static int vdec_g_fmt(struct file *file, void *fh, struct v4l2_format *f) > struct venus_inst *inst = to_inst(file); > const struct venus_format *fmt = NULL; > struct v4l2_pix_format_mplane *pixmp = &f->fmt.pix_mp; > + int ret; > > if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) > fmt = inst->fmt_cap; > else if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) > fmt = inst->fmt_out; > > - if (inst->reconfig) { > - struct v4l2_format format = {}; > - > - inst->out_width = inst->reconfig_width; > - inst->out_height = inst->reconfig_height; > - inst->reconfig = false; > - > - format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE; > - format.fmt.pix_mp.pixelformat = inst->fmt_cap->pixfmt; > - format.fmt.pix_mp.width = inst->out_width; > - format.fmt.pix_mp.height = inst->out_height; > - > - vdec_try_fmt_common(inst, &format); > - > - inst->width = format.fmt.pix_mp.width; > - inst->height = format.fmt.pix_mp.height; > + if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) { > + ret = wait_event_timeout(inst->reconf_wait, inst->reconfig, > + msecs_to_jiffies(100)); > + if (!ret) > + return -EINVAL; inst->reconfig is only true during the time between a reconfigure event and the start of the CAPTURE queue. This looks like G_FMT on the CAPTURE queue will only be successful during this very short amount of time. Is my understanding correct? I wonder whether I am missing something here because the Chromium tests are all passing. But if this is correct, then this looks very restrictive. For instance, one would not be able to do VIDIOC_G_FMT twice in a row. > } > > pixmp->pixelformat = fmt->pixfmt; > @@ -457,6 +447,10 @@ vdec_try_decoder_cmd(struct file *file, void *fh, struct v4l2_decoder_cmd *cmd) > if (cmd->flags & V4L2_DEC_CMD_STOP_TO_BLACK) > return -EINVAL; > break; > + case V4L2_DEC_CMD_START: > + if (cmd->flags & V4L2_DEC_CMD_START_MUTE_AUDIO) > + return -EINVAL; > + break; > default: > return -EINVAL; > } > @@ -477,18 +471,23 @@ vdec_decoder_cmd(struct file *file, void *fh, struct v4l2_decoder_cmd *cmd) > > mutex_lock(&inst->lock); > > - /* > - * Implement V4L2_DEC_CMD_STOP by enqueue an empty buffer on decoder > - * input to signal EOS. > - */ > - if (!(inst->streamon_out & inst->streamon_cap)) > - goto unlock; > + if (cmd->cmd == V4L2_DEC_CMD_STOP) { > + /* > + * Implement V4L2_DEC_CMD_STOP by enqueue an empty buffer on > + * decoder input to signal EOS. > + */ > + if (!(inst->streamon_out & inst->streamon_cap)) > + goto unlock; > > - fdata.buffer_type = HFI_BUFFER_INPUT; > - fdata.flags |= HFI_BUFFERFLAG_EOS; > - fdata.device_addr = 0xdeadbeef; > + fdata.buffer_type = HFI_BUFFER_INPUT; > + fdata.flags |= HFI_BUFFERFLAG_EOS; > + fdata.device_addr = 0xdeadb000; > > - ret = hfi_session_process_buf(inst, &fdata); > + ret = hfi_session_process_buf(inst, &fdata); > + > + if (!ret && inst->codec_state == DEC_STATE_DECODING) > + inst->codec_state = DEC_STATE_DRAIN; > + } > > unlock: > mutex_unlock(&inst->lock); > @@ -649,20 +648,18 @@ static int vdec_output_conf(struct venus_inst *inst) > return 0; > } > > -static int vdec_init_session(struct venus_inst *inst) > +static int vdec_session_init(struct venus_inst *inst) > { > int ret; > > ret = hfi_session_init(inst, inst->fmt_out->pixfmt); > - if (ret) > + if (ret == -EINVAL) > + return 0; Why is -EINVAL ok? It would be helpful to have at least a comment to explain this behavior. > + else if (ret) > return ret; > > - ret = venus_helper_set_input_resolution(inst, inst->out_width, > - inst->out_height); > - if (ret) > - goto deinit; > - > - ret = venus_helper_set_color_format(inst, inst->fmt_cap->pixfmt); > + ret = venus_helper_set_input_resolution(inst, frame_width_min(inst), > + frame_height_min(inst)); > if (ret) > goto deinit; > > @@ -681,26 +678,19 @@ static int vdec_num_buffers(struct venus_inst *inst, unsigned int *in_num, > > *in_num = *out_num = 0; > > - ret = vdec_init_session(inst); > - if (ret) > - return ret; > - > ret = venus_helper_get_bufreq(inst, HFI_BUFFER_INPUT, &bufreq); > if (ret) > - goto deinit; > + return ret; > > *in_num = HFI_BUFREQ_COUNT_MIN(&bufreq, ver); > > ret = venus_helper_get_bufreq(inst, HFI_BUFFER_OUTPUT, &bufreq); > if (ret) > - goto deinit; > + return ret; > > *out_num = HFI_BUFREQ_COUNT_MIN(&bufreq, ver); > > -deinit: > - hfi_session_deinit(inst); > - > - return ret; > + return 0; > } > > static int vdec_queue_setup(struct vb2_queue *q, > @@ -733,6 +723,10 @@ static int vdec_queue_setup(struct vb2_queue *q, > return 0; > } > > + ret = vdec_session_init(inst); > + if (ret) > + return ret; > + > ret = vdec_num_buffers(inst, &in_num, &out_num); > if (ret) > return ret; > @@ -758,6 +752,11 @@ static int vdec_queue_setup(struct vb2_queue *q, > inst->output_buf_size = sizes[0]; > *num_buffers = max(*num_buffers, out_num); > inst->num_output_bufs = *num_buffers; > + > + mutex_lock(&inst->lock); > + if (inst->codec_state == DEC_STATE_CAPTURE_SETUP) > + inst->codec_state = DEC_STATE_STOPPED; > + mutex_unlock(&inst->lock); > break; > default: > ret = -EINVAL; > @@ -794,80 +793,298 @@ static int vdec_verify_conf(struct venus_inst *inst) > return 0; > } > > -static int vdec_start_streaming(struct vb2_queue *q, unsigned int count) > +static int vdec_start_capture(struct venus_inst *inst) > { > - struct venus_inst *inst = vb2_get_drv_priv(q); > int ret; > > - mutex_lock(&inst->lock); > + if (!inst->streamon_out) > + return -EINVAL; > > - if (q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) > - inst->streamon_out = 1; > - else > - inst->streamon_cap = 1; > + if (inst->codec_state == DEC_STATE_DECODING) { > + if (inst->reconfig) > + goto reconfigure; > > - if (!(inst->streamon_out & inst->streamon_cap)) { > - mutex_unlock(&inst->lock); > + venus_helper_queue_dpb_bufs(inst); > + venus_helper_process_initial_cap_bufs(inst); > + inst->streamon_cap = 1; > return 0; > } > > - venus_helper_init_instance(inst); > + if (inst->codec_state != DEC_STATE_STOPPED) > + return -EINVAL; > > - inst->reconfig = false; > - inst->sequence_cap = 0; > - inst->sequence_out = 0; > +reconfigure: > + ret = hfi_session_flush(inst, HFI_FLUSH_OUTPUT); > + if (ret) > + return ret; > > - ret = vdec_init_session(inst); > + ret = vdec_output_conf(inst); > if (ret) > - goto bufs_done; > + return ret; > + > + ret = venus_helper_set_num_bufs(inst, inst->num_input_bufs, > + VB2_MAX_FRAME, VB2_MAX_FRAME); > + if (ret) > + return ret; > + > + ret = venus_helper_intbufs_realloc(inst); > + if (ret) > + goto err; > + > + ret = venus_helper_alloc_dpb_bufs(inst); > + if (ret) > + goto err; > + > + ret = venus_helper_queue_dpb_bufs(inst); > + if (ret) > + goto free_dpb_bufs; > + > + ret = venus_helper_process_initial_cap_bufs(inst); > + if (ret) > + goto free_dpb_bufs; > + > + venus_helper_load_scale_clocks(inst->core); > + > + ret = hfi_session_continue(inst); > + if (ret) > + goto free_dpb_bufs; > + > + inst->codec_state = DEC_STATE_DECODING; > + > + inst->streamon_cap = 1; > + inst->sequence_cap = 0; > + inst->reconfig = false; > + > + return 0; > + > +free_dpb_bufs: > + venus_helper_free_dpb_bufs(inst); > +err: > + return ret; > +} > + > +static int vdec_start_output(struct venus_inst *inst) > +{ > + int ret; > + > + if (inst->codec_state == DEC_STATE_SEEK) { > + ret = venus_helper_process_initial_out_bufs(inst); > + inst->codec_state = DEC_STATE_DECODING; > + goto done; > + } > + > + if (inst->codec_state == DEC_STATE_INIT || > + inst->codec_state == DEC_STATE_CAPTURE_SETUP) { > + ret = venus_helper_process_initial_out_bufs(inst); > + goto done; > + } > + > + if (inst->codec_state != DEC_STATE_UNINIT) > + return -EINVAL; > + > + venus_helper_init_instance(inst); > + inst->sequence_out = 0; > + inst->reconfig = false; > > ret = vdec_set_properties(inst); > if (ret) > - goto deinit_sess; > + return ret; > > ret = vdec_output_conf(inst); > if (ret) > - goto deinit_sess; > + return ret; > > ret = vdec_verify_conf(inst); > if (ret) > - goto deinit_sess; > + return ret; > > ret = venus_helper_set_num_bufs(inst, inst->num_input_bufs, > VB2_MAX_FRAME, VB2_MAX_FRAME); > if (ret) > - goto deinit_sess; > + return ret; > > - ret = venus_helper_alloc_dpb_bufs(inst); > + ret = venus_helper_vb2_start_streaming(inst); > if (ret) > - goto deinit_sess; > + return ret; > > - ret = venus_helper_vb2_start_streaming(inst); > + ret = venus_helper_process_initial_out_bufs(inst); > if (ret) > - goto deinit_sess; > + return ret; > > - mutex_unlock(&inst->lock); > + inst->codec_state = DEC_STATE_INIT; > + > +done: > + inst->streamon_out = 1; > + return ret; > +} > + > +static int vdec_start_streaming(struct vb2_queue *q, unsigned int count) > +{ > + struct venus_inst *inst = vb2_get_drv_priv(q); > + int ret; > + > + mutex_lock(&inst->lock); > + > + if (q->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) > + ret = vdec_start_capture(inst); > + else > + ret = vdec_start_output(inst); > > + if (ret) > + goto error; > + > + mutex_unlock(&inst->lock); > return 0; > > -deinit_sess: > - hfi_session_deinit(inst); > -bufs_done: > +error: > venus_helper_buffers_done(inst, VB2_BUF_STATE_QUEUED); > + mutex_unlock(&inst->lock); > + return ret; > +} > + > +static void vdec_dst_buffers_done(struct venus_inst *inst, > + enum vb2_buffer_state state) This function is only called as follows: vdec_dst_buffers_done(inst, VB2_BUF_STATE_ERROR); Therefore the state argument does not seem particularly useful. Maybe we can omit it and give this function a more specific name like vdec_cancel_dst_buffers(). > +{ > + struct vb2_v4l2_buffer *buf; > + > + while ((buf = v4l2_m2m_dst_buf_remove(inst->m2m_ctx))) > + v4l2_m2m_buf_done(buf, state); > +} > + > +static int vdec_stop_capture(struct venus_inst *inst) > +{ > + int ret = 0; > + > + switch (inst->codec_state) { > + case DEC_STATE_DECODING: > + ret = hfi_session_flush(inst, HFI_FLUSH_ALL); > + vdec_dst_buffers_done(inst, VB2_BUF_STATE_ERROR); > + inst->codec_state = DEC_STATE_STOPPED; > + break; > + case DEC_STATE_DRAIN: > + vdec_dst_buffers_done(inst, VB2_BUF_STATE_ERROR); > + inst->codec_state = DEC_STATE_STOPPED; > + break; You can simplify these two cases a bit: case DEC_STATE_DECODING: ret = hfi_session_flush(inst, HFI_FLUSH_ALL); /* fallthrough */ case DEC_STATE_DRAIN: vdec_dst_buffers_done(inst, VB2_BUF_STATE_ERROR); inst->codec_state = DEC_STATE_STOPPED; break; > + case DEC_STATE_DRC: Just caught this now, but what does "DRC" stand for?