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 Sentinel firmware:
$ wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-sentinel-0.10.bin
$ chmod +x firmware-sentinel-0.10.bin
$ ./firmware-sentinel-0.10.bin
$ cp firmware-sentinel-0.10/mx93a0-ahab-container.img .
Download DDR firmware:
$ wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-imx-8.20.bin
$ chmod +x firmware-imx-8.20.bin
$ ./firmware-imx-8.20.bin
$ cp firmware-imx-8.20/firmware/ddr/synopsys/* .
Download and build imx_mkimage:
$ git clone https://github.com/nxp-imx/imx-mkimage -b lf-6.1.22_2.0.0
$ cd imx-mkimage
$ make soc=iMX9
$ cp iMX9/soc.mak mkimage_imx8 ..
$ cd ..
Download and build ATF:
$ git clone https://github.com/varigit/imx-atf -b lf_v2.8_var01
$ cd imx-atf
$ source /opt/fsl-imx-xwayland/6.1-mickledore/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/ .
Build boot image:
$ make -f soc.mak clean
$ make -f soc.mak SOC=iMX9 dtbs=" imx93-var-som-symphony.dtb" MKIMG=./imx-mkimage/mkimage_imx8 PAD_IMAGE=./pad_image.sh CC=gcc flash_singleboot
$ mv flash.bin imx-boot-sd.bin
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.)