[Sound-open-firmware] [PATCH v2 00/12] [RESEND] ASoC: SOF DSP virtualisation

[Guennadi Liakhovetski]

Hi Mark,

On Fri, Apr 03, 2020 at 10:28:42AM +0100, Mark Brown wrote:
> On Fri, Apr 03, 2020 at 11:13:54AM +0200, Guennadi Liakhovetski wrote:
> > This patch series extends the SOF driver to add support for DSP
> > virtualisation to ASoC. It is built on top of VirtIO, contains a
> > guest driver and a vhost in-kernel guest driver. This version
> > supports a single playback and a single capture interface on the
> > guest. The specific guest audio topology is supplied by the host
> 
> I've asked a couple of times for documentation of the protocol here but
> don't think I've seen anything yet?

Sorry, we were thinking about the best way to reply. I think Liam will 
provide more procise information. The API we are using is the same as 
what is already used by SOF to communicate with the DSP firmware. With 
VirtIO we re-use the same IPC messages as those, used with the DSP, 
they are just transmitted over Virtual Queues. Additionally to existing 
IPC messages the SOF VirtIO implementation defines 3 more message types 
for topology loading and DSP power management. IPC message types are 
defined in include/sound/sof/header.h, IPC overview is available in 
https://thesofproject.github.io/latest/developer_guides/linux_driver/architecture/sof_driver_arch.html#ipc-processing 
but I'm not aware of a formal SOF IPC protocol documentation.

Thanks
Guennadi