Re: [PATCH 10/28] venus: vdec: call session_continue in insufficient event

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Stanimir,

On 2018-05-03 17:06, Stanimir Varbanov wrote:
Hi Vikash,

Thanks for the comments!

On  2.05.2018 09:26, Vikash Garodia wrote:
Hello Stanimir,

On 2018-04-24 18:14, Stanimir Varbanov wrote:
Call session_continue for Venus 4xx version even when the event
says that the buffer resources are not sufficient. Leaving a
comment with more information about the workaround.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@xxxxxxxxxx>
---
 drivers/media/platform/qcom/venus/vdec.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/media/platform/qcom/venus/vdec.c
b/drivers/media/platform/qcom/venus/vdec.c
index c45452634e7e..91c7384ff9c8 100644
--- a/drivers/media/platform/qcom/venus/vdec.c
+++ b/drivers/media/platform/qcom/venus/vdec.c
@@ -873,6 +873,14 @@ static void vdec_event_notify(struct venus_inst
*inst, u32 event,

             dev_dbg(dev, "event not sufficient resources (%ux%u)\n",
                 data->width, data->height);
+            /*
+             * Workaround: Even that the firmware send and event for
+             * insufficient buffer resources it is safe to call
+             * session_continue because actually the event says that
+             * the number of capture buffers is lower.
+             */
+            if (IS_V4(core))
+                hfi_session_continue(inst);
             break;
         case HFI_EVENT_RELEASE_BUFFER_REFERENCE:
             venus_helper_release_buf_ref(inst, data->tag);

Insufficient event from video firmware could be sent either,
1. due to insufficient buffer resources
2. due to lower capture buffers

It cannot be assumed that the event received by the host is due to lower capture buffers. Incase the buffer resource is insufficient, let say there is a bitstream resolution switch from 720p to 1080p, capture buffers needs to be reallocated.

I agree with you. I will rework this part and call session_continue
only for case #2.

Even if the capture buffers are lower, driver should consider reallocation of capture buffers with required higher count. Without this, it may happen that for a given video frame, the decoded output will not be generated. The fact that the DPB buffer count is same as capture buffers, will be lower than required. Hence the frame which needs YUV reference beyond the DPB count, will get stuck as it cannot be decoded due to unavailability
of sufficient DPB buffers.
Say for ex. 10 DPB and capture buffers are allocated. For a given bitstream, firmware requested the count to be 15. Frame 1 to 10 gets decoded and stored in DPB as references for future frame decoding. Now when the 11th frame is queued to firmware, it can be decode but cannot be stored as reference to decode future (12th) frame. Hence 11 frame will get stuck and will not be given
back to host driver.


The driver should be sending the V4L2_EVENT_SOURCE_CHANGE to client instead of ignoring
the event from firmware.

The v4l2 event is sent always to v4l clients.

regards,
Stan
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [Linux for Sparc]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux