On Thu, Sep 1, 2022 at 11:58 AM SHARMA, JYOTIRMOY <jyotirmoy.sha...@amd.com>
wrote:
> [AMD Official Use Only - General]
>
> Hi all,
>
Hello Jyotirmoy.
[sorry for the possible format issues]
>
>
> Forgot to mention that I am able to play audio from HVM guest with Pulse
> Audio as back end.
>
good.
> Here is the corresponding HVM configuration:
>
>
>
> vsnd = [[ 'card, backend=Domain-0, buffer-size=65536, short-name=VCard,
> long-name=Virtual sound card, sample-rates=44100, sample-formats=s16_le',
> 'pcm, name=dev1', 'stream, unique-id=pulse, type=P' ]]
>
>
>
> I have used xen front end and snd_be (along with libxenbe) as back end as
> suggested by Christopher earlier in this thread.
>
>
>
> Only when I change unique-id=alsa, audio is not working from HVM guest.
>
>
>
> If anyone has tried ALSA back end (instead of PA), please let me know what
> I am missing.
>
We use snd_be over pulse and it works fine. I am not too familiar with all
that sound's internals. But I would suggest looking at the following thread
where Oleksandr Grytsov (the author of the snd_be) mentioned the need of HW
parameters matching for alsa [1].
I made an experiment with alsa (however I am not 100% sure whether it is
correct), nevertheless details are below.
I changed guest config to use alsa:
vsnd = [[ 'card, backend=DomD, buffer-size=65536, short-name=VCard,
long-name=Virtual sound card,
sample-rates=8000;11025;16000;22050;32000;44100;48000,
sample-formats=s16_le',
'pcm, name=dev1', 'stream, unique-id=alsa, type=P'
]]
And checked that snd_be started using alsa:
03.07.22 03:37:17.185 | SndFrontend | DBG - Parse stream id: alsa
03.07.22 03:37:17.186 | SndFrontend | DBG - Create pcm device, type: ALSA,
device: , propName: , propValue:
...
With that command running in DomU I heard the audio in headphones:
root@salvator-x-h3-4x2g-xt-domu:~# cat /dev/urandom | aplay -f S16_LE -c 2
-D hw:0,0
Playing raw data 'stdin' : Signed 16 bit Little Endian, Rate 8000 Hz, Stereo
This is the output of "aplay -l" in both domains just in case:
root@salvator-x-h3-4x2g-xt-domd:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: rcarsound [rcar-sound], device 0: rsnd-dai.0-ak4613-hifi
ak4613-hifi-0 []
Subdevices: 0/1
Subdevice #0: subdevice #0
root@salvator-x-h3-4x2g-xt-domu:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: vsnd [], device 0: dev1 [Virtual card PCM]
Subdevices: 1/1
Subdevice #0: subdevice #0
Please check your HW params as suggested at [1].
[1]
https://lore.kernel.org/xen-devel/cacvf2ow7ghcldkqyi8w1s7-fbux8zcawanfza07xhvg-ioa...@mail.gmail.com/
>
>
> Regards,
>
> Jyotirmoy
>
>
>
--
Regards,
Oleksandr Tyshchenko
