[alsa-devel] dmix and sounds less than 64kb

[Aaron "Caustik" Robinson]

This is on an embedded ARM device, with a custom driver. That's interesting.
I never thought about the cache angle. Is there any sort of hack I can put
to check if that is the problem?

On 7/10/07, Jaroslav Kysela <perex at suse.cz> wrote:
>
> On Mon, 9 Jul 2007, Aaron "Caustik" Robinson wrote:
>
> > We actually dumped the pcm data as it was arriving to the driver (via
> the
> > trigger start and irq functions), and it was corrupted at that point.
> Also I
> > have dumped the pcm data after it has been mixed by the dmix plugin, and
> it
> > is fine there as well.
>
> Which hardware and driver? It seems like a driver (wrong pointer
> management) or hardware issue. For example, ARM CPUs does not guarantee
> cache coherency between two virtual address spaces pointing to one
> physical space.
>
>                                         Jaroslav
>
> > On 7/9/07, Takashi Iwai <tiwai at suse.de> wrote:
> > >
> > > At Fri, 6 Jul 2007 20:28:13 -0700,
> > > Aaron "Caustik" Robinson wrote:
> > > >
> > > > We have been having one heck of a time tracking down the cause of
> some
> > > ALSA
> > > > audio playback issues.
> > > >
> > > > It appears that any time we play a very short sound (<64kb), either
> the
> > > > sound doesn't play at all, or only a fragment of it plays. We
> haven't
> > > had
> > > > much luck finding a solution to this issue, then I found this thread
> on
> > > the
> > > > history of this email group:
> > > >
> > > >
> > >
> http://mailman.alsa-project.org/pipermail/alsa-devel/2007-April/000526.html
> > > >
> > > > Our problem is pretty much exactly like his issues relating to <64k
> > > sounds.
> > > >
> > > > My question is - has anybody else run into this problem? To the OP
> of
> > > the
> > > > above thread, if you're still listening - did you ever find a
> solution
> > > to
> > > > your problem? I'd be very interested to hear any help you can
> provide.
> > >
> > > It works fine with my systems, so the problem should be pretty
> > > driver-specific...
>
> -----
> Jaroslav Kysela <perex at suse.cz>
> Linux Kernel Sound Maintainer
> ALSA Project, SUSE Labs
>