[BUG] distortion during playback on MTL-NOCODEC

[keqiaozhang]

Describe the bug
we observed the waveform distortion on MTL-NOCODEC, we have a similar issue SOF#6727 on mtl-stable-002, but it has been fixed on 002 branch, so let's use this bug to track the distortion issue on main branch.

To Reproduce
~/sof-test/test-case/check-alsabat.sh -p hw:sofnocodec,0 -c hw:sofnocodec,0 -C 2

Reproduction Rate
100%

Environment
Kernel Branch: topic/sof-dev
Kernel Commit:
c41b1735d3da
SOF Branch: main
SOF Commit:
e6f72dee8289
Platform: MTL-NOCODEC

bat.wav.3Vbz0k.zip

[lgirdwood]

Looks like we are missing a fix from mtl-002 @mwasko ?

[juimonen]

This is because of missing link clock setting in mtl/ace platforms in ssp driver.

mtl 003 branch has a hard coded quick fix for "link clock", but that is not in sof main.

"non hard coded" fix is coming from:
zephyrproject-rtos/zephyr#53297

after this, there also needs to be a topology change for mtl to configure/set the link clock.

[wszypelt]

Reproduction test under implementation

[keqiaozhang]

This issue still exists in CI.

[lgirdwood]

ok, looks like we could still be missing a MTL branch patch in main @mwasko fyi.

[juimonen]

So we seem to have 2 overlapping bugs here:

1. link clock setting in mtl (this should not cause choppiness, but will amplify it)

• there is a fix pending for it topology2: ssp: add link clock aux data for mtl #7060

2. even without anything link clock related we have the choppiness:

• [ADL/TGL/MTL NOCODEC] Frequency response is different between left and right channel #7184
• something is fishy in the feedback stream

[fredoh9]

I tested with mtl-004(2eec99b). alsabat test failed there also but waveforms are totally different. @abonislawski Do we miss any patch on main branch? Upper one is mtl-004, lower one is main branch(85367b7).

alsabat_wav_capture.zip