[Sound-open-firmware] Question about scheduling IPC task vs pipeline task

[Ranjani Sridharan]

On Tue, 2020-04-21 at 23:55 +0300, Daniel Baluta wrote:
> Hi Tomasz,
> 
> Running aplay I get this timeout, on kernel side:
> 
> sof-audio-of 3b6e8000.dsp: error: ipc timed out for 0x60040000 size
> 12
> This is the command for SOF_IPC_STREAM_TRIG_START.
Hi Daniel,

Do you have any further logs in dmesg? Usually, timeouts are followed
by any DSP FW exceptions IIRC.
Is the DSP still after you see the timeout?

Thanks,
Ranjani
> 
> What I notice on SOF side is:
> 
> -> irq_handle (new message from SOF arrives)
>   -> ipc_schedule_process
>     -> schedule_ipc_task
>        -> run: ipc_platform_do_cmd
>            -> pipeline_trigger()
>             -> schedule pipe_task
>               -> then pipeline_copy starts to RUN
> 
> Now the problem is that even if pipeline_copy() runs in a separate
> schedulable task, ipc_task doesn't get a chance to run so the reply
> for TRIGGER command isn't sent back to host hence the timeout.
> 
> My question:
> 
> Does pipeline_copy() runs in some special context so that normal EDF
> tasks
> can meet their deadline?
> 
> I do have a slightly new firmware then the kernel, not sure about
> what recent
> changes have been done to firmware.
> 
> thanks,
> Daniel.
> _______________________________________________
> Sound-open-firmware mailing list
> Sound-open-firmware at alsa-project.org
> https://mailman.alsa-project.org/mailman/listinfo/sound-open-firmware