[Sound-open-firmware] NXP 8M Plus platform suitable for SOF getting started

[Daniel Baluta]

Hi Martin,

See my answers inline.

On Thu, Feb 11, 2021 at 11:25 PM <martin.roessler at roessler-netz.de> wrote:
>
> Hello SOF Team,
>
> I would like to get started with SOF: I'm interested in audio signal processing, audio driver programming and hardware.
> I do this to some extend during my normal work, however, for new things to learn there is never time.

Good to hear that. Care to elaborate what kind of projects are you
targeting? What kind
of audio signal processing algorithms are you top priorities.

We are now scoping and talking with various customers in order to
understand what
algorithms we should plan on implementing or at least provide an easy interface
for integration.

You might have reached this page, just to make an idea where we sit at
the moment:

https://thesofproject.github.io/latest/algos/index.html#supplied-processing-algorithms
>
> So, I’m looking for a suitable NXP board for SOF. I would like to use the new i.MX8M Plus if possible or is it better to use one of the NXP platforms mention in the sof documentation?
>
> I could not find any NXP "native" 8M Plus board on the web page, however, there is a device tree file imx8mp-evk-sof-wm8960.dts indicating there is one?

Yes, there is an i.MX8MP Evaluation board and has SOF support with NXP
BSP software.
I can get in touch with sales team at NXP and get back at you with
more details in private.

> All 3rd party 8M Plus board vendors I contacted so far are not so familiar with the Hifi4 core, so not much help, especially when asking about JTAG access to this core.

Ok, it makes sense. 8M Plus is quite a new design.

> Could you give any recommendation of a not so expensive board (> ~ 500 US$) suitable for SOF?

You can use i.MX8QXP/ i.MX8QM reference boards. I am not familiar with
the latest prices. They
might be a little bit more expensive than 500$. But there is also a
good chance that you can
get a cheaper boards from NXP vendors.

There is NXP community support with people very knowledgeable about available
pricing options on:

https://community.nxp.com/t5/i-MX-Processors/bd-p/imx-processors

>
> Also I'm unclear how to get technical information of the Hifi4 core. Nothing mentioned in the SOC datasheets so far.
> I could use one of the Tensilica licenses of my company I work for. But do I need to contact NXP or Cadence?. Any NDA required?

What kind of technical information you need? Most of getting started
technical info can be found inside the source code on github.
You will need a license to use Xtensa toolchain, but just for
prototyping you can go with GCC based toochain.
>
> I have already a i.MX 8M Mini EVK for Android learning and a i.MX RT600 EVK just for fun.
> So, just a maybe stupid question:
> Any plans to support SOF together with a "normal" Cortex-M4 / Cortex-M7 accelerator core on the (NXP) SOCs?
> Now that it is possible to use Zephyr as RTOS, I think this would be possible, at least for some not too complex audio pipelines.

Everything is possible since SOF is an open source project. Someone
just needs to do it.

At NXP, on the short term we are planning to use Zephyr as RTOS on
HIFI4 (mind that this is available now
only on intel platforms).
Also, it is on my todo list (as a side project) to give it a try with
SOF and i.MX RT variants.

thanks,
Daniel.