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:
Configure compilation environment:
Cleanup everything:
Select configuration:
Build U-Boot:
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:
Download DDR firmware:
wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-imx-8.26.1-410be01.bin
chmod +x firmware-imx-8.26.1-410be01.bin
./firmware-imx-8.26.1-410be01.bin
cp firmware-imx-8.26.1-410be01/firmware/ddr/synopsys/* .
Download imx_mkimage:
git clone https://github.com/nxp-imx/imx-mkimage -b lf-6.6.52-2.2.2
cp imx-mkimage/iMX8M/*.c imx-mkimage/iMX8M/*.sh imx-mkimage/scripts/*.sh .
cp dtb_check.sh ../scripts/
Download and build ATF:
git clone https://github.com/varigit/imx-atf -b lf_v2.10_6.6.52-2.2.2_var01
git clone https://github.com/varigit/meta-variscite-bsp-imx -b scarthgap_6.6.52-2.2.2_var01
cd imx-mkimage
git apply ../meta-variscite-bsp-imx/recipes-bsp/imx-mkimage/imx-boot/0001-iMX8M-soc-allow-dtb-override.patch
git apply ../meta-variscite-bsp-imx/recipes-bsp/imx-mkimage/imx-boot/0002-iMX8M-soc-change-padding-of-DDR4-and-LPDDR4-DMEM-fir.patch
rm *.patch
cp iMX8M/soc.mak ..
cd ..
cd imx-atf
source /opt/fsl-imx-xwayland/6.6-scarthgap/environment-setup-armv8a-poky-linux
unset LDFLAGS
make PLAT=imx8mp bl31
cp build/imx8mp/release/bl31.bin ..
cd ..
Copy U-Boot binaries:
cp ../tools/mkimage mkimage_uboot
cp ../u-boot.bin .
cp ../u-boot-nodtb.bin ../spl/u-boot-spl.bin ../arch/arm/dts/imx8mp-var-dart-dt8mcustomboard.dtb ../arch/arm/dts/imx8mp-var-som-symphony.dtb ../arch/arm/dts/imx8mp-var-smarc-echo.dtb .
Build boot image:
make -f soc.mak clean
make -f soc.mak SOC=iMX8MP SOC_DIR=imx-boot-tools dtbs="imx8mp-var-dart-dt8mcustomboard.dtb imx8mp-var-som-symphony.dtb imx8mp-var-smarc-echo.dtb" MKIMG=./mkimage_imx8 PAD_IMAGE=./pad_image.sh CC=gcc OUTIMG=imx-boot-sd.bin flash_evk
Install the Built U-Boot on an SD Card¶
sudo dd if=imx-boot-sd.bin 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:
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.)