.. SPDX-License-Identifier: GPL-2.0+

How to Update U-Boot on imx6ulz_smm_m2 and imx6ulz_smm_m2b boards
=================================================================

Required software on the host PC:

- UUU: https://github.com/NXPmicro/mfgtools

Build U-Boot for m2:

.. code-block:: bash

   $ make mrproper
   $ make imx6ulz_smm_m2_defconfig
   $ make

Build U-Boot for m2b:

.. code-block:: bash

   $ make mrproper
   $ make imx6ulz_smm_m2b_defconfig
   $ make

This generates the SPL and u-boot-dtb.img binaries.

Loading U-Boot via USB Serial Download Protocol
-----------------------------------------------

Copy SPL and u-boot-dtb.img to the uuu folder.

Load the U-Boot via USB:

.. code-block:: bash

   $ sudo uuu -v -b nand_script.lst u-boot-with-spl.imx

where nand_script.lst contains the following:

.. code-block::

   uuu_version 1.2.39

   # @_flash.bin            | bootloader
   # @_image   [_flash.bin] | image burn to nand, default is the same as bootloader

   # This command will be run when i.MX6/7 i.MX8MM, i.MX8MQ
   SDP: boot -f _flash.bin

   # This command will be run when ROM support stream mode
   # i.MX8QXP, i.MX8QM
   SDPS: boot -f _flash.bin

   # These commands will be run when use SPL and will be skipped if no spl
   # SDPU will be deprecated. please use SDPV instead of SDPU
   # {
   SDPU: delay 1000
   SDPU: write -f _flash.bin -offset 0x57c00
   SDPU: jump
   # }

   # These commands will be run when use SPL and will be skipped if no spl
   # if (SPL support SDPV)
   # {
   SDPV: delay 1000
   SDPV: write -f _flash.bin -offset 0x11000
   SDPV: jump
   # }

   FB: ucmd setenv fastboot_buffer ${loadaddr}
   FB: download -f _image
   FB: ucmd if test ! -n "$fastboot_bytes"; then setenv fastboot_bytes $filesize; else true; fi
   # Burn image to nandfit partition if needed
   FB: ucmd if env exists nandfit_part; then nand erase.part nandfit; nand write ${fastboot_buffer} nandfit ${fastboot_bytes}; else true; fi;
   FB: ucmd nandbcb init ${fastboot_buffer} nandboot ${fastboot_bytes}
   FB: Done

Then U-Boot starts and its messages appear in the console program.

Use the default environment variables:

=> env default -f -a

=> saveenv
