Jetson nano pin mux as a GPIO

Robotics & Edge Computing Jetson Systems Jetson Nano
22

hello babbelal.patel1,

you may check $ dmesg | grep DTS for the device tree blob you’re currently using.
for example,

$ dmesg | grep DTS
[    0.232238] DTS File Name: /dvs/git/dirty/git-master_linux/kernel/kernel-4.9/arch/arm64/boot/dts/../../../../../../hardware/nvidia/platform/t210/porg/kernel-dts/tegra210-p3448-0000-p3449-0000-b00.dts

it’s using tegra210-p3448-0000-p3449-0000-b00.dtb, and you shall find the binary file under /boot/dtb/

here’s commands to disassembler the dtb binary file into text file,
for example, $ dtc -I dtb -O dts -o output.txt tegra210-p3448-0000-p3449-0000-b00.dtb
thanks

23

dmesg | grep DTS
[ 0.211805] DTS File Name: …/arch/arm64/boot/dts/…/…/…/…/…/…/hardware/nvidia/platform/t210/porg/kernel-dts/tegra210-p3448-0002-p3449-0000-b00.dts
[ 0.420093] DTS File Name: …/arch/arm64/boot/dts/…/…/…/…/…/…/hardware/nvidia/platform/t210/porg/kernel-dts/tegra210-p3448-0002-p3449-0000-b00.dts

tegra210-p3448-0002-p3449-0000-b00.dts is very small file. I have attached. please check.
tegra210-p3448-0002-p3449-0000-b00.dts (3.4 KB)

Above content is not here like " gpio: gpio@6000d000". This dts file is very small So please let me know. Where I can add it?

24

hello babbelal.patel1,

this doesn’t look correct, did you compile this device tree blob binary by your own?
in addition, did you works with Nano DevKits?

25

I have grep and disassembler running dtb file. Please check now.
Please let me know, In which file I need to update if add new IC?

dmesg | grep DTS
[ 0.211805] DTS File Name: …/arch/arm64/boot/dts/…/…/…/…/…/…/hardware/nvidia/platform/t210/porg/kernel-dts/tegra210-p3448-0002-p3449-0000-b00.dts
[ 0.420093] DTS File Name: …/arch/arm64/boot/dts/…/…/…/…/…/…/hardware/nvidia/platform/t210/porg/kernel-dts/tegra210-p3448-0002-p3449-0000-b00.dts

dtc -I dtb -O dts -o output.txt tegra210-p3448-0002-p3449-0000-b00.dtb

output.txt (284.2 KB)

26

hello babbelal.patel1,

this looks correct device tree blob for Nano platform.
please check below device tree sources, if you’re using Nano DevKits,
i.e. $L4T_Sources/r32.6.1/Linux_for_Tegra/source/public/hardware/nvidia/platform/t210/porg/kernel-dts/