[alsa-devel] Managing resources of DSP from arm core side

[Daniel Baluta]

Hi Peter,

Liam mentioned that at some point (when working for OMAP)
you might have had the same challenge I'm facing now.

I'm trying to figure out how to properly manage resources needed by
the IPs configured
by DSP.

On i.MX8 we the following scenario:

- Application processor (arm64) exposes an ALSA sound card to applications
- DSP (Hifi4) does the processing

DSP has direct access to  DAI registers but it doesn't have (easily)
access to other resources
like: pinctrl, power-domain, clocks, etc.

I was wondering how did you tackled this for OMAP?

I have already created a dummy CPU DAI on Linux that it will take care
of this [1].

It is a part of a Back End link like this (simplified view):

links[i].cpus->name = "dummy_dai";
links[i].platforms->name = "dsp";
links[i].codecs->name = "cs42888";
links[i].no_pcm = 1;

It works pretty well for basic playback / capture.

thanks,
Daniel.

[1] https://marc.info/?l=alsa-devel&m=158022296519597&w=2