[FEATURE] sof-test should run without DMA trace - only etrace

[plbossart]

Is your feature request related to a problem? Please describe.

Facts:

• Most distributions do not enable DMA trace (considered a developer option). This can be overridden with a kernel parameter but doing so changes what users report.
• The DMA trace is known to be invasive (bandwidth, etc) and either creates issues or prevent overflows ([BUG][BYT][CHT] Linux 5.11 Cherrytrail/rt5640 emits persistent beeping sound after a short while sof#3868 (comment))

We should be able to run sof-tests, possibly in a more limited version since less information is available, without requiring the DMA trace to be enabled.

Describe the solution you'd like
autodetection that only /sys/kernel/debug/sof/etrace is available and skips of all DMA trace parsing/error detection

Describe alternatives you've considered
none

@lgirdwood @kv2019i @marc-hb @aiChaoSONG @fredoh9 @ranj063 @lyakh FYI

[marc-hb]

We already have a -s option: #681

What's missing and and what level? In run-all-tests.sh marc-hb@run-all-nologger ?

[plbossart]

@marc-hb I don't want to disable sof-logger (which will read the etrace which is ALWAYS enabled).

I just want to disable the DMA trace.... (sof-logger -t) which is conditionally enabled by the kernel.

[plbossart]

See e.g. thesofproject/sof#3673, how would one run such tests if we cannot disable the DMA trace...

[marc-hb]

I just tried modprobe snd_sof sof_debug=0 as documented at https://thesofproject.github.io/latest/developer_guides/debugability/logger/index.html but the firmware seems to still receive the same ipc: debug cmd 0x30000 request from the kernel to enable the DMA trace.

[plbossart]

@marc-hb try PR thesofproject/linux#3021, that disables the trace for real. The current code can only enable the trace with the module parameter, not disable it.

[marc-hb]

@marc-hb try PR thesofproject/linux#3021, that disables the trace for real.

Does not apply to CI but in my workspace I found it easier to turn off CONFIG_SND_SOC_SOF_DEBUG_ENABLE_FIRMWARE_TRACE. Then I upgraded sof_insert.sh to support modules parameters (#734) and with that a simple ./test-case/check-playback.sh -s runs fine and passes. As I wrote earlier, the etrace still works.

[marc-hb]

#811 to disable the logger entirely (even etrace)

[plbossart]

#811 to disable the logger entirely (even etrace)

that's not what I was asking - only disable DMA traces and keep etrace

[marc-hb]

I know, that's why this is not closed.

[plbossart]

this is still open IMHO