zephyr: enable HIFI_SHARING if DP scheduler is enabled with HIFI

[kv2019i]

If data processing (DP) scheduler is enabled on Xtensa HiFi platforms, CONFIG_HIFI_SHARING should be enabled as well. Otherwise modules running via DP scheduler cannot use HiFi extensions (as the HiFi register state is not saved and restored on context switches).

[lgirdwood]

@wszypelt @lrudyX good to merge ?

[kv2019i]

@wszypelt @lgirdwood It seems the fail is a System.BadImageFormatException on TGL only, so could be an issue with test infra and not the PR. In general, this is a rather invasive change, so regressions are also possible.

[lgirdwood]

SOFCI TEST

[lgirdwood]

@wszypelt @lgirdwood It seems the fail is a System.BadImageFormatException on TGL only, so could be an issue with test infra and not the PR. In general, this is a rather invasive change, so regressions are also possible.

Lets run CI again to be sure.

[lgirdwood]

@wszypelt @lgirdwood It seems the fail is a System.BadImageFormatException on TGL only, so could be an issue with test infra and not the PR. In general, this is a rather invasive change, so regressions are also possible.

Lets run CI again to be sure.

Results as expected so looks fine. @wszypelt @lrudyX good to merge (CI still pending) ?

[wszypelt]

@lgirdwood @kv2019i first there was a problem with one of the machines, after fix there is a issue IPC error 6 in updownmixer for PTL, I still need some time to check it out

[marcinszkudlinski]

According to @wszypelt findings

This change in fact is enabling HiFi preemption, developed by Zephyr some time ago. I was under impression it had been enabled in SOF right after Zephyr change was merged, but looks like it had not.

Such change at kernel level may of course cause a random and hard to track crashes because of races etc. and the result above suggest we do have such issue :(

Required test - start a pipeline with an LL module using HiFI and a DP module (on the same core. also using hifi) with a long processing time (10ms). This would enforce HiFI preemption. Run such test several times.

So at the moment DON"T MERGE IT, we need to prove that HiFI preemption is a problem and go back to Zephyr team for investigation

[lgirdwood]

@rljordan @nashif fyi - looks like we need to deep dive Zephyr HiFi context switching as 1st step.

[lgirdwood]

@kv2019i @marcinszkudlinski any updates ?

Have we tried rerunning CI and downgrade HIFI version to see if this changes result ? i.e it could be a HiFi4 only issue that would shine the light on any new Hifi4 logic/registers.

Also HiFi has audio processing instructions (which would probably glitch/distort) and also some general purpose instructions/registers (e.g. loops, loads, stores) that may more likely be the culprit here if we are seeing unexpected IPC results.

One other thing is that I dont think the HiFi version Kconfig has impact outside of modules today (since it only for intrinsics), i.e. general purpose code would still use HiFi version that's baked into CC.

[marcinszkudlinski]

@lgirdwood @kv2019i we DO need hifi preemption @wszypelt pls provide test

Debugging won't be easy :(

[wszypelt]

@kv2019i @marcinszkudlinski sure thing, we are during creating new test, but we still need some time