U-Boot for LibreTech AC¶
LibreTech AC is a single board computer manufactured by Libre Technology with the following specifications:
Amlogic S805X ARM Cortex-A53 quad-core SoC @ 1.2GHz
ARM Mali 450 GPU
512MiB DDR4 SDRAM
10/100 Ethernet
HDMI 2.0 4K/60Hz display
40-pin GPIO header
4 x USB 2.0 Host
eMMC, SPI NOR Flash
Infrared receiver
Schematics are available on the manufacturer website.
U-Boot compilation¶
$ export CROSS_COMPILE=aarch64-none-elf-
$ make libretech-ac_defconfig
$ make
Image creation¶
For simplified usage, pleaser refer to Pre-Generated FIP file set with codename lafrite
Amlogic doesn’t provide sources for the firmware and for tools needed to create the bootloader image, so it is necessary to obtain them from the git tree published by the board vendor:
$ wget https://releases.linaro.org/archive/13.11/components/toolchain/binaries/gcc-linaro-aarch64-none-elf-4.8-2013.11_linux.tar.xz
$ wget https://releases.linaro.org/archive/13.11/components/toolchain/binaries/gcc-linaro-arm-none-eabi-4.8-2013.11_linux.tar.xz
$ tar xvfJ gcc-linaro-aarch64-none-elf-4.8-2013.11_linux.tar.xz
$ tar xvfJ gcc-linaro-arm-none-eabi-4.8-2013.11_linux.tar.xz
$ export PATH=$PWD/gcc-linaro-aarch64-none-elf-4.8-2013.11_linux/bin:$PWD/gcc-linaro-arm-none-eabi-4.8-2013.11_linux/bin:$PATH
$ git clone https://github.com/BayLibre/u-boot.git -b libretech-ac amlogic-u-boot
$ cd amlogic-u-boot
$ wget https://raw.githubusercontent.com/BayLibre/u-boot/libretech-cc/fip/blx_fix.sh
$ make libretech_ac_defconfig
$ make
$ export UBOOTDIR=$PWD
Download the latest Amlogic Buildroot package, and extract it :
$ wget http://openlinux2.amlogic.com:8000/ARM/filesystem/Linux_BSP/buildroot_openlinux_kernel_4.9_fbdev_20180418.tar.gz
$ tar xfz buildroot_openlinux_kernel_4.9_fbdev_20180418.tar.gz buildroot_openlinux_kernel_4.9_fbdev_20180418/bootloader
$ export BRDIR=$PWD/buildroot_openlinux_kernel_4.9_fbdev_20180418
Go back to mainline U-Boot source tree then :
$ mkdir fip
$ cp $UBOOTDIR/build/scp_task/bl301.bin fip/
$ cp $UBOOTDIR/build/board/amlogic/libretech_ac/firmware/bl21.bin fip/
$ cp $UBOOTDIR/build/board/amlogic/libretech_ac/firmware/acs.bin fip/
$ cp $BRDIR/bootloader/uboot-repo/bl2/bin/gxl/bl2.bin fip/
$ cp $BRDIR/bootloader/uboot-repo/bl30/bin/gxl/bl30.bin fip/
$ cp $BRDIR/bootloader/uboot-repo/bl31/bin/gxl/bl31.img fip/
$ cp u-boot.bin fip/bl33.bin
$ sh $UBOOTDIR/blx_fix.sh \
fip/bl30.bin \
fip/zero_tmp \
fip/bl30_zero.bin \
fip/bl301.bin \
fip/bl301_zero.bin \
fip/bl30_new.bin \
bl30
$ $BRDIR/bootloader/uboot-repo/fip/acs_tool.pyc fip/bl2.bin fip/bl2_acs.bin fip/acs.bin 0
$ sh $UBOOTDIR/blx_fix.sh \
fip/bl2_acs.bin \
fip/zero_tmp \
fip/bl2_zero.bin \
fip/bl21.bin \
fip/bl21_zero.bin \
fip/bl2_new.bin \
bl2
$ $BRDIR/bootloader/uboot-repo/fip/gxl/aml_encrypt_gxl --bl3enc --input fip/bl30_new.bin
$ $BRDIR/bootloader/uboot-repo/fip/gxl/aml_encrypt_gxl --bl3enc --input fip/bl31.img
$ $BRDIR/bootloader/uboot-repo/fip/gxl/aml_encrypt_gxl --bl3enc --input fip/bl33.bin
$ $BRDIR/bootloader/uboot-repo/fip/gxl/aml_encrypt_gxl --bl2sig --input fip/bl2_new.bin --output fip/bl2.n.bin.sig
$ $BRDIR/bootloader/uboot-repo/fip/gxl/aml_encrypt_gxl --bootmk \
--output fip/u-boot.bin \
--bl2 fip/bl2.n.bin.sig \
--bl30 fip/bl30_new.bin.enc \
--bl31 fip/bl31.img.enc \
--bl33 fip/bl33.bin.enc
and then write the image to SD with:
$ DEV=/dev/your_sd_device
$ dd if=fip/u-boot.bin.sd.bin of=$DEV conv=fsync,notrunc bs=512 skip=1 seek=1
$ dd if=fip/u-boot.bin.sd.bin of=$DEV conv=fsync,notrunc bs=1 count=444