Nvcsi -- sot (Start of Transmission) Checks

Hello All,

I want to confirm that Nvcsi controller receives the SOT (Start of Transmission)
from CSI2 Tx.

How to do this?

Balaji N

I use this little script to turn on tracing. The trace log isn’t the easiest thing in the world to read but you can glean some valuable information like start-of-frame. You can read the trace output from /sys/kernel/debug/tracing/trace or, if you use this script, you’ll find a symlink to that file in ~nvidia/trace.


# Use this to gain insight into the errors coming fro the camera CPU.

[ "$UID" != "0" ] && echo 'Root access is required.' && exit 1

# Shorten the path to the trace log with this fun and useful symlink!
if [ ! -e ~nvidia/trace ]; then
    ln -s /sys/kernel/debug/tracing/trace ~nvidia/trace

echo 1 > /sys/kernel/debug/tracing/tracing_on
echo 30720 > /sys/kernel/debug/tracing/buffer_size_kb
echo 1 > /sys/kernel/debug/tracing/events/tegra_rtcpu/enable
echo 1 > /sys/kernel/debug/tracing/events/freertos/enable
echo 2 > /sys/kernel/debug/camrtc/log-level
# This resets the trace log
echo > /sys/kernel/debug/tracing/trace

hello BalajiNP,

you may also check https://elinux.org/Jetson_TX2/28.1_Camera_BringUp for more details.