Custom board with AGX Xavier SoM is not booting

Hi Team,

we are facing issues while bring up of custom board with AGX Xavier SoM. board is not booting and I am not getting any boot up logs also. How to debug this?

Note: I have connected same AGX SoM to Devkit and checked it is booting fine.



If you cannot see boot up logs from uart, then I would suggest you can check your hardware design with the design guide first.

Are you able to flash the board? Any log from uart when flashing the board?


I am not able to flash from the custom board.
After some time flasjing failed with these errors,
[ 41.8379 ] tegrarcm_v2 --ismb2
[ 41.8409 ] USB communication failed.Check if device is in recovery
[ 41.8570 ]
[ 41.8620 ] tegradevflash_v2 --iscpubl
[ 41.8650 ] Cannot Open USB
[ 41.8809 ]
Error: None of the bootloaders are running on device. Check the UART log.
Failed flashing t186ref.

debug logs while flashing,
[0005.872] I> UPH��
[0000.903] W> RATCHET: MB1 binary ratchet value 4 is too large than ratchet level 2 from HW fuses.
[0000.911] I> MB1 (prd-version:
[0000.917] I> Boot-mode: Platform RCM
[0000.920] I> Chip revision : A02P
[0000.923] I> Bootrom patch version : 15 (correctly patched)
[0000.928] I> ATE fuse revision : 0x200
[0000.932] I> Ram repair fuse : 0x0
[0000.935] I> Ram Code : 0x2
[0000.937] I> rst_source : 0x0
[0000.940] I> rst_level : 0x0
[0000.944] I> USB configuration success
[0003.030] I> mb2 image downloaded
[0003.052] I> Recovery boot mode 0
[0003.056] I> Boot-device: eMMC

I am getting serial logs now. attached full flash logs.
agx_custom_logs.txt (64.1 KB)


Now getting boot logs. but still board is not booting completely.
Attached logs here.

logs.txt (6.8 KB)

If even flash cannot pass, please compare your hardware with the design guide and also the BCT configuration under your Linux_for_Tegra/bootloader.

Now we are able to flash the board completely. But the board is still not booting.
Attached boot logs
logs.txt (6.8 KB)

Any inputs will be highly helpful for us


Hi Wayne
This is Ganesh. I am working with Arun Kumar. We have designed the carrier board as per AGX Design guide document.

The custom carrier board is designed for Auto Power ON mode without Button MCU.
The power sequence are verified and it is fine.

Using our carrier board we are able to successfully enter into FORCE RECOVERY mode. And flashing also get completed 100%.

But the SoM is not booting. If anything specifically to be probed or monitored please let us know,


I cannot answer the question for hardware. I will let other engineers to help check.

If the boot stuck in the same place every time, please check the log from devkit and see what should be printed after the stuck point.

custom board booting till “tag initialized” log and getting stuck at this place. As per devkit next log should be “emc initialized”. Any idea what causes this issue?



Hi, please check Chapter 15. Debug and Strapping in OEM DG to make sure your design does not violate that so that all relevant pins are in correct status. Also there are checklist sheet attached in OEM DG file, please use that to check your design items one by one.

Hi @JerryChang ,

I have checked the MB1 Configuration Changes, in Security Configuration, it was mentioned that the security configuration files will be kept as “./hardware/​nvidia/​platform/​t19x/​common/​bct/​scr/bct-scr-cbb-mini-p3668.cfg”.

I have checked this directory and I didn’t find this file there.
Can you help in verifying the security configuration for our custom board?


Are you using a module that enables the security setting and hit this problem on your custom board?


we are not using any security module on the carrier board. we are assuming that the security module is already present on the SoM module and needs these changes mentioned in the last post.


I would suggest you can verify what @Trumany suggested in previous comment first.

Other users don’t change their security configuration but their board can work fine.

Hi @WayneWWW,

We are using Auto Power ON without button MCU. We don’t have force recovery mode button for taking the board into recovery mode, instead we are using a jumper which is connected to take into recovery board.

For this kind of design, is there any changes required in the mb1 bootloader configuration files other than pinmux and padvoltage cfg?



we are able to bring up custom board with AGX Xavier SoM. There is some Hardware issue on our custom board, we have corrected it.

Thanks for the support

Would you like to share what kind of hardware issue is that?


We are using an alternate P-MOSFET for enabling 12V and 5V input to SoM Module’s SYS_VIN_HV & SYS_VIN_MV.
Initially, we have configured the Vgs of the MOSFET as -2.5V. We found the RDS resistance is more at this Vgs condition. Further, we have tuned the Vgs to -4.5V and the issue is resolved.

We assume the SYS_VIN_MV might not able to get sufficient current to complete flashing/booting. With the above HW modification the carrier board allows the system to flash and boot.

Thanks for the support @WayneWWW, @Trumany & @JerryChang

Chithambara Ganesh

Can you share a screenshot of this P-MOSFET part initial schematic? It might be helpful for others.