TX1 TTYS0 UART Debug, Fail to Powerup

Robotics & Edge Computing Jetson & Embedded Systems Jetson TX1
1

Hello there. I have a device on the TTYS0 UART, and it brings up before the jetson, sending some data to Tx1 from the UART port, which u-boot confuses it to be a keyboard input, and it enters to the boot debug mode.

I don’t want this happening, and I tried to modify the u-boot source codes, built it again, and flashed the u-boot.

export DEVDIR=/home/burak/JetPack-L4T-3.3/64_TX1/Linux_for_Tegra
export CROSS_COMPILE=/usr/local/gcc-linaro-5.3-2016.02-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu- 
export CROSS32CC=/usr/local/gcc-linaro-5.3-2016.02-x86_64_arm-linux-gnueabihf/bin/arm-linux-gnueabihf-gcc 
export KERNEL_MODULES_OUT=$DEVDIR/images/modules
export TEGRA_KERNEL_OUT=$DEVDIR/images
export ARCH=arm64

cd $DEVDIR/sources/u-boot/
make distclean
make p2371-2180_defconfig
make
sudo cp -f $DEVDIR/sources/u-boot/u-boot* $DEVDIR/bootloader/t210ref/p2371-2180/
cd $DEVDIR/
sudo ./flash.sh -k LNX jetson-tx1 mmcblk0p1

I managed to flash the uboot, and it boots up fine after the flash.

But when I power off/power on, it wont boot, only black screen. (Doesn’t even push debug messages to the serial port)

I switched back the u-boot modifications, but I still can’t boot. It only boots when I flash it. (dtb or uboot…) Now I can’t manage to fix my Tx1, it only works if I flash it, and doesn’t work if I dont.

I help need on three questions;

  1. How do I compile the u-boot and flash it the correct way?
  2. How can I close the ttyS0 Uart Debug console? So it won’t enter to the boot debug mode when the device sends data?
  3. How can I fix now-broken tx1? Getting the original .bin files and flashing again didn’t seem to work.

Thank you.

Here are the results of me trying to flash the u-boot if anyone is interested;

log_EBT_flash.txt (15.1 KB)
log_LNX_flash.txt (11 KB)

2

Downloaded a fresh Jetpack 3.3, and flashed the tx1 with it.

It booted up just fine after the flash, sending debug messages through the serial as well (checking with usb-serial of my host pc.)

I didn’t do anything, pressed the power button and held it down. It shut down.

After that, tried to boot it again with pressing 1 time to the power button. Still, it can’t cold boot. Only black screen, not even serial debug.

Also, the jetson + board used to draw 0.5A of current when it worked without problems, but now it draw 0.3~A. So it makes me wonder if the Jetson even gets power.

EDIT: When I power it on, tried to run the command which should’nt be successfull since the device is not in recovery mode;

sudo ./flash.sh -k LNX jetson-tx1 mmcblk0p1 2>&1 | tee log_LNX_flash.txt

Which actually was successfull flashing. I just powered it on, didn’t put it into Recovery Mode myself.

I figured it automatically enters to the Recovery Mode by itself.

3

FYI, the Jetson will never automatically go into recovery mode. The recovery button must be held while cycling power for that to occur.

4

Still having problems with this. Is there any -proven- u-boot compiling and flashing resource/guide I can use?

Thank you.

5

Which specific release (instructions differ depending on release)? There is a U-Boot customization section in the official docs. If you go here, and then click on the particular release:
[url]https://developer.nvidia.com/embedded/linux-tegra-archive[/url]
…there would be a “Documentation” URL. This is html format documentation and you can use your web browser to see the U-Boot content.