Tonight I've done the linux loader util.

Step by step guide:

1. build kernel

use default config for stm32:

make ARCH=arm CROSS_COMPILE=arm-none-eabi- stm32_defconfig 

setup CONFIG_DRAM_BASE, CONFIG_DRAM_SIZE, CONFIG_XIP_PHYS_ADDR

make ARCH=arm CROSS_COMPILE=arm-none-eabi- menuconfig 

make:

make -j ARCH=arm CROSS_COMPILE=arm-none-eabi- 

preparing & compile correct DT

2. coping xipImage & *.dtb on SD card

3. run load command

Next step - build latest busybox and make rootfs.