On 25 April 2017 at 08:10, Don Kuzhiyelil dku@sysgo.com wrote:
Hello,
I am trying to use Coresight drivers on Juno r0 board with 4.9 Linux sources (Linaro release 17.01 with 'latest-armlt').
I have tried the configuration with ETM as the source and ETF as the sink and it is working as expected. But with ETR as the sink, when stopping the tracing, kernel panic occurs.
The bug can be reproduced with the following steps: / # echo 1 > /sys/bus/coresight/devices/20070000.etr/enable_sink / # echo 1 > /sys/bus/coresight/devices/22040000.etm/enable_source / # echo 0 > /sys/bus/coresight/devices/22040000.etm/enable_source
Sometime the system also hangs without printing panic message.
I am attaching the log file and .config file along with this mail. From the logs, it looks like an arm SCP firmware problem. Let me know if I am missing some steps/configuration or If this is a know hardware/firmware problem with hopefully some workarounds existing.
Hi Don,
From the above snapshot I assume you are using CS from sysFS. Note
that if you want to use Perf you will need to use the perf-opencsd-4.9 branch we have on gitHub.
Yes, the PC and LR registers in the core dump do point to a FW problem. Make sure you have the latest FW installed on the platform. We had to do work in that area to make sure the power controller doesn't switch off components while they are in use.
Thanks, Mathieu
Thanks and regards, Don Kuzhiyelil
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