Changes (added logs) made in Cboot not reflected


In order to debug a issue in my board , i have made changes (added extra logs) in

/BSP/Linux_for_Tegra/cboot/NX_Cboot_Source/cboot_src_t19x/bootloader/partner/common/drivers$ vi sdmmc/tegrabl_sd_card.c

But changes made are reflected.

Steps we followed are :

Building the CBoot Binary

To build the CBoot binary:

  1. Extract the CBoot-standalone source with the command:
    mkdir cboot
    tar -xjf cboot_src_t194.tbz2 -C cboot
    cd cboot

  2. Export the cross compiler tools with the following enviroment variables:
    export CROSS_COMPILE=aarch64-linux-gnu-

Where: <your_64-bit_ARM_toolchain_triple> can be: ‘aarch64-linux-gnu-’

  1. Set the TEGRA_TOP and TOP environment variables:
    export TEGRA_TOP=$PWD
    export TOP=$PWD

  2. Build the T194 CBoot binary, lk.bin, with the command:
    make -C ./bootloader/partner/t18x/cboot PROJECT=t194 TOOLCHAIN_PREFIX="${CROSS_COMPILE}" DEBUG=2 BUILDROOT="${PWD}"/out NV_TARGET_BOARD=t194ref NV_BUILD_SYSTEM_TYPE=l4t NOECHO=@

The binary is located at: ‘./out/build-t194/…’:


  1. Rename the binary lk.bin to cboot_t194.bin to use with the Jetson Xavier (T194)
    Linux for Tegra Board Support Package.

This CBoot binary replaces the one provided at: Linux_for_Tegra/bootloader/cboot_t194.bin.

Please help me with the solution and modification if required in anyof the above steps.

How did you flash your board to update the cboot?

We prepare SD card image by using this command
sudo ./ -o sd-blob_nx.img -b jetson-xavier-nx-devkit

And flash it sd card into dev kit.

No, you need to use to flash.

We prepare image by
sudo ./ -o sd-blob_nx.img -b jetson-xavier-nx-devkit

and make SD card bootable by balenaEtcher

That method cannot update cboot.

Actually , as our custom carrier board is not booting , hence we are trying to put logs in cboot code and trying to debug the issue.

Could you please help us with the correct method to implement it.

You filed 5 topics doing similar things in few days. It is not hard for me to know what you are doing.

Use devkit to flash the cboot first. Follow the quick start guide as I told you just few hours ago.

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