Hi VIncent
On Wed, 15 Jan 2025 at 09:11, V E vincent.ernst@web.de wrote:
Hi Mike,
I was able to initialise the ETMs by replacing the hex phandle references with labels. For the funnels, I used "arm,coresight-funnel" like specified in the bindings of kernel 4.9, which seems to fix it. When enabling the sinks and sources via sysfs, I get the expected messages in dmesg. There are no connections folders, though.
OK thats good. The connections information was added sometime in the kernel 5.x series.
So registering the CoreSight devices seems to works, but I guess that there is only limited tracing functionality because the drivers are so old?
sysfs tracing should be OK - this is no more than switching on a source to trace into a sink and collect data.
Where you may suffer is if you try to use perf. We have made a lot of enhancements and bugfixes on how perf processes trace data since 4.9
Unfortunately, Nvidia's Linux for my Jetson Nano ("Linux for Tegra") only supports kernel 4.9.
I guessed this might be the case
There exist community solutions for getting a version 5 kernel running (on Ubuntu), but I would prefer keeping the standard Linux for Tegra if possible.
What surprises me is that ...0000.etf/status (shown here [1]) does not exist on my device and I also couldn't find it in the ABI documentation. Do you have an idea what that is?
This looks like a printout of many of the ETF registers in a single sysfs file. e.g. RRP, RWP, STATUS etc. Having multiple output lines for a single sysfs file is something that the upstream maintainers frown upon so has likely been dropped. You should still be able to see the same output by reading each individual register
Regards
Mike
Best regards,
Vincent
[1] https://docs.nvidia.com/jetson/archives/l4t-archived/l4t-3275/index.html#pag... _______________________________________________ CoreSight mailing list -- coresight@lists.linaro.org To unsubscribe send an email to coresight-leave@lists.linaro.org