[PATCH] ASoC: amd:Replacing MSI with Legacy IRQ model

[RAVULAPATI, VISHNU VARDHAN RAO]

[AMD Official Use Only - Internal Distribution Only]



On Tue, 22 Dec 2020 12:59:18 +0100,
Ravulapati Vishnu vardhan rao wrote:
>
> When we try to play and capture simultaneously we see that
> interrupts are genrated but our handler is not being acknowledged,
> After investigating further more in detail on this issue we found
> that IRQ delivery via MSI from the ACP IP is unreliable and so sometimes
> interrupt generated will not be acknowledged so MSI model shouldn't be used
> and using legacy IRQs will resolve interrupt handling issue.
>
> This patch replaces MSI interrupt handling with legacy IRQ model.
>
> Issue can be reproduced easily by running below python script:
>
> import subprocess
> import time
> import threading
>
> def do2():
>   cmd = 'aplay -f dat -D hw:2,1 /dev/zero -d 1'
>     subprocess.call(cmd, stdin=subprocess.PIPE,
>                        stderr=subprocess.PIPE, shell=True)
>     print('Play Done')
>
> def run():
>        for i in range(1000):
>                do2()
>
> def do(i):
>     cmd = 'arecord -f dat -D hw:2,2 /dev/null -d 1'
>     subprocess.call(cmd, stdout=subprocess.PIPE,
>                        stderr=subprocess.PIPE, shell=True)
>     print(datetime.datetime.now(), i)
>
> t = threading.Thread(target=run)
> t.start()
> for i in range(1000):
>        do(i)
>
> t.join()
>
> After applying this patch issue is resolved.
>
> Signed-off-by: Ravulapati Vishnu vardhan rao <Vishnuvardhanrao.Ravulapati at amd.com>

>Is this specific to Raven, i.e. Renoir doesn't need >the same fix?
>If so, it should be mentioned in the patch >description.

We will send this fix as separate patch for Renoir.

Thanks,
Vishnu