SPI Local Loop on Jetson Nano B01 4GB

Below is my extlinux.conf of my jetson nano.
should I change “/boot/kernel_tegra210-p3448-0000-p3449-0000-b00-user-custom.dtb” rather than “/boot/dtb/kernel_tegra210-p3448-0000-p3449-0000-b00.dtb” ?

> TIMEOUT 30
DEFAULT JetsonIO

MENU TITLE L4T boot options

LABEL primary
      MENU LABEL primary kernel
      LINUX /boot/Image
      INITRD /boot/initrd
      APPEND ${cbootargs} quiet root=/dev/mmcblk0p1 rw rootwait rootfstype=ext4 console=ttyS0,115200n8 console=tty0 fbcon=map:0 net.ifnames=0 

# When testing a custom kernel, it is recommended that you create a backup of
# the original kernel and add a new entry to this file so that the device can
# fallback to the original kernel. To do this:
#
# 1, Make a backup of the original kernel
#      sudo cp /boot/Image /boot/Image.backup
#
# 2, Copy your custom kernel into /boot/Image
#
# 3, Uncomment below menu setting lines for the original kernel
#
# 4, Reboot

# LABEL backup
#    MENU LABEL backup kernel
#    LINUX /boot/Image.backup
#    INITRD /boot/initrd
#    APPEND ${cbootargs}

LABEL JetsonIO
	MENU LABEL Custom Header Config: <HDR40 User Custom [2024-08-14-154032]>
	LINUX /boot/Image
	FDT /boot/kernel_tegra210-p3448-0000-p3449-0000-b00-user-custom.dtb
	INITRD /boot/initrd
	APPEND ${cbootargs} quiet root=/dev/mmcblk0p1 rw rootwait rootfstype=ext4 console=ttyS0,115200n8 console=tty0 fbcon=map:0 net.ifnames=0