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Yocto Build U-Boot from source code

Toolchain Installation for Out of Yocto Builds

To install the toolchain, follow the Yocto Toolchain installation guide.

Build U-Boot Out of Yocto Tree

Obtain sources:

git clone https://github.com/varigit/uboot-imx.git -b lf_v2024.04_6.6.52-2.2.0_var01
cd uboot-imx

Configure compilation environment:

source /opt/fsl-imx-xwayland/6.6-scarthgap/environment-setup-armv8a-poky-linux

Cleanup everything:

make mrproper

Select configuration:

make imx93_var_som_defconfig

Build U-Boot:

make -j$(nproc)

Build Boot Image

The final boot image contains multiple firmware files, as explained by NXP in IMX_LINUX_USERS_GUIDE.pdf (Search for "How to build imx-boot image by using imx-mkimage").

The following procedure builds the final image:

Create imx-boot-tools directory:

mkdir imx-boot-tools
cd imx-boot-tools

Download Sentinel firmware:

wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-ele-imx-1.3.0-17945fc.bin
chmod +x firmware-ele-imx-1.3.0-17945fc.bin
./firmware-ele-imx-1.3.0-17945fc.bin
cp firmware-ele-imx-1.3.0-17945fc/mx93a1-ahab-container.img .

Download DDR firmware:

wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-imx-8.26-d4c33ab.bin
chmod +x firmware-imx-8.26-d4c33ab.bin
./firmware-imx-8.26-d4c33ab.bin
cp firmware-imx-8.26-d4c33ab/firmware/ddr/synopsys/* .

Download and build imx_mkimage:

git clone https://github.com/nxp-imx/imx-mkimage -b lf-6.6.52_2.2.0
cd imx-mkimage
make soc=iMX93
cp iMX93/soc.mak mkimage_imx8 ..
cd ..

Download and build ATF:

git clone https://github.com/varigit/imx-atf -b lf_v2.10_6.6.52-2.2.0_var01

cd imx-atf
source /opt/fsl-imx-xwayland/6.6-scarthgap/environment-setup-armv8a-poky-linux
unset LDFLAGS
make PLAT=imx93 bl31
cp build/imx93/release/bl31.bin ..
cd ..

Copy U-Boot binaries:

cp ../tools/mkimage mkimage_uboot
cp ../u-boot.bin .
cp ../spl/u-boot-spl.bin ../arch/arm/dts/imx93-var-som-symphony.dtb ../arch/arm/dts/imx93-var-dart-dt8mcustomboard.dtb .

Build boot image:

make -f soc.mak clean
make -f soc.mak  SOC=iMX93  dtbs="imx93-var-dart-dt8mcustomboard.dtb imx93-var-som-symphony.dtb"  MKIMG=./imx-mkimage/mkimage_imx8 PAD_IMAGE=./pad_image.sh  CC=gcc flash_singleboot
mv flash.bin imx-boot

Install the Built U-Boot on an SD Card

sudo dd if=imx-boot of=/dev/sdX bs=1K seek=32 conv=fsync

(Replace /dev/sdX with the correct device)

If you want to use our recovery SD card to flash the built U-Boot to NAND flash/eMMC, then copy it to the appropriate location in the SD card:

sudo cp imx-boot /media/rootfs/opt/images/…

And eject the SD card gracefully from host machine.

Note: If you manually upgrade an existing U-Boot, and you have an old environment saved, it is a good idea to reset your environment to the new default.)

Update Your U-Boot Out of Yocto Tree

git pull