Initrd_flash changing extlinux.conf

[riz94107]

I’m using l4t_initrd_flash.shto create a bootable disk image under L4T R35.4.1 - everything is working more or less, EXCEPT that I can’t get the bootable image to use my custom DTB file - no matter what I do, the process of building the image winds up with the flash.sh script calling its update_fdt_line function which causes it to CHANGE the extlinux.conf that I wrote, so that the line

FDT /boot/olyns-custom.dtb

becomes
FDT /boot/dtb/kernel_tegra194-p3668-0001-p3509-0000.dtb

… but that DTB does not have the needed changes for my application.

I’ve tried a number of things to get this to stop, or to work around it, but all the various scripts are written in a way that’s quite hard to understand.

I’ve ALSO tried calling the script with ADDITIONAL_DTB_OVERLAY_OPT set to the DTBO file which has the needed changes, but it doesn’t seem to help.

Suggestions please?
+j

[DaveYYY]

You have to specify the device tree to be used in the board config file.
I don’t think we have ever thought users to do it by manually modifying extlinux.conf…
I don’t know how you came up with the idea doing it this way…

For example, in jetson-xavier-nx-devkit.conf:

BLBlockSize=1048576;
EMMC_CFG=flash_l4t_t194_spi_sd_p3668.xml;
DTB_FILE=tegra194-p3668-0000-p3509-0000.dtb;
RECROOTFSSIZE=100MiB
MISC_COLD_BOOT_CONFIG="tegra194-mb1-bct-misc-sd-l4t.cfg";

Change the DTB_FILE line.