Jetson/TX2 DTB

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Starting on Jetson TX2, the Device Tree Binary (DTB) is no longer specified by default in /boot/extlinux/extlinux.conf. This is to allow u-boot to pass parameter to load the specific DTB file. However if you have compiled your own DTB, there are ways to set it yourself.
Please refer to the steps according to your JetPack release version.

R27.1

Modifying the Existing extlinux.conf

Although L4T by default no longer sets the FDT entry in extlinux.conf, users can still manually set this for the change to take effect. Note the DTB field added back into /boot/etxlinux/extlinux.conf below:

  TIMEOUT 30
  DEFAULT primary
  MENU TITLE p2771-0000 eMMC boot options
  LABEL primary
     MENU LABEL primary kernel
     LINUX /boot/Image
     FDT /boot/tegra186-quill-p3310-1000-c03-00-base.dtb
     APPEND fbcon=map:0 net.ifnames=0 console=tty0 OS=l4t console=ttyS0,115200n8 memtype=0 video=tegrafb no_console_suspend=1 earlycon=uart8250,mmio32,0x03100000 gpt tegraid=18.1.2.0.0 tegra_keep_boot_clocks maxcpus=6 android.kerneltype=normal androidboot.serialno=0335115020673 vpr_resize root=/dev/mmcblk0p1 rw rootwait

Before Flashing

The default DTB can also be set before flashing by modifying jetson-tx2.conf located inside ../Linux_for_Tegra_tx2 directory on the host PC. Set the path to the desired DTB in jetson-tx2.conf, then proceed with flashing.

If extlinux.conf is also edited with FDT option, then extlinux.conf will override what is specified in jetson-tx2.conf at the time of flashing.

R28.1

Replace the dtb file with your own build, and update the DTB with the following commands.

TX1

Replace your own build DTB with

JetPack/3.1/64_TX1/Linux_for_Tegra_64_tx1/kernel/dtb/tegra210-jetson-tx1-p2597-2180-a01-devkit.dtb

flash the DTB partition with

sudo ./flash -r -k DTB jetson-tx1 mmcblk0p1

TX2

Replace your own build DTB with

[TX2]
JetPack/3.1/64_TX2/Linux_for_Tegra_64_tx2/kernel/dtb/tegra186-quill-p3310-1000-[a00|c03]-00-base.dtb
[TX2i]
JetPack/3.1/64_TX2/Linux_for_Tegra_64_tx2/kernel/dtb/tegra186-quill-p3489-1000-a00-00-ucm1.dtb

flash the DTB partition with

sudo ./flash -r -k kernel-dtb jetson-tx2 mmcblk0p1

Discussion Thread

  1. extlinux.conf: FDT No Longer Used for DTB File Specification?
  2. method to modify/use different device tree in R28.1