[PATCH] coresight: tmc-etr: Don't enable ETR when it's not ready

[James Clark]

On 24/01/2023 20:09, Yabin Cui wrote:
> Ping for review. And I still can't reproduce it, even if I reduced the
> timeout to 2us and tried different workloads. Any suggestions for how
> to reproduce it?
> 

Hi Yabin,

I just found this in my kernel log files from a few days ago.

Jan 19 15:03:35 n1-sdp kernel: [865337.521413] coresight tmc_etr0:
timeout while waiting for completion of Manual Flush
Jan 19 15:03:35 n1-sdp kernel: [865337.529351] coresight tmc_etr0:
timeout while waiting for TMC to be Ready

This is on N1SDP, and I've only been running "normal" perf commands like:

  perf record -e cs_etm//k --  taskset -c 2 sleep 1
  perf record -e cs_etm//  -- stress -c 2 -t 1

I also haven't been able to reproduce it since

James