GMSL camera capture video fail

[sammyb7qw7]

I use MAX9296+MAX9295+ar0234 GMSL camera in L4T R35.1 with AGX ORIN.
My camera output format is YUV422 8bit.

I can’t capture video by Qt V4L2 test utility after AGX ORIN boot up.

So I try to enable debug tracing message.

But I find capture video will success by Qt V4L2 test utility after I send below command:

echo 1 > /sys/kernel/debug/bpmp/debug/clk/nvcsi/mrq_rate_locked

May I to know why this command is working? and what’s action in this command.

How to setup the default value of /sys/kernel/debug/bpmp/debug/clk/nvcsi/mrq_rate_locked to 1?

[JerryChang]

hello sammyb7qw7,

that’s one of commands to boost the clocks.
since it’s camera stack to parse settings via device tree. that should be an issue with your clock configurations.
moreover, there’re some bug fixes and it’s more stable for using JP-5.1 (l4t-r35.2.1) or later release.

[sammyb7qw7]

OK, I will move it to L4T R35.2.1 release.

In the other hand, The pix_clk_hz setting is ‘pix_clk_hz=“186250000”’ in my current device tree.
Does the pix_clk_hz value need to increase or decrease?
May I to know how to calcute this pix_clk_hz value?

[JerryChang]

hello sammyb7qw7,

FYI, JetPack 5.1.1 is now live. JetPack 5.1.1 / l4t-r35.3.1 is public today,
you may see-also developer guide for formulas to calculate sensor pixel clock.
and… it should be SerDes Pixel Clock, serdes_pix_clk_hz, for sensor modules that use serializer/deserializer chips (GMSL or FPD link),