U-Boot for ODROID-N2/N2+ (S922X)

ODROID-N2 and ODROID-N2+ are a Single Board Computers manufactured by Hardkernel with the following specifications:

  • Amlogic S922X ARM Cortex-A53 dual-core + Cortex-A73 quad-core SoC

  • 4GB DDR4 SDRAM

  • Gigabit Ethernet

  • HDMI 2.1 4K/60Hz display

  • 40-pin GPIO header

  • 4 x USB 3.0 Host, 1 x USB OTG

  • eMMC, microSD

  • Infrared receiver

ODROID-N2+ uses Rev-C silicon allowing higher CPU opp-points. U-Boot contains logic to read the model detail from SARADC and select the correct device-tree file if FDTDIR is used instead of an FDT reference to a specfic device-tree.

Schematics are available on the manufacturer website: https://wiki.odroid.com

U-Boot Compilation

$ export CROSS_COMPILE=aarch64-none-elf-
$ make odroid-n2_defconfig
$ make

U-Boot Signing with Pre-Built FIP repo

$ git clone https://github.com/LibreELEC/amlogic-boot-fip --depth=1
$ cd amlogic-boot-fip
$ mkdir my-output-dir
$ ./build-fip.sh odroid-n2 /path/to/u-boot/u-boot.bin my-output-dir

U-Boot Manual Signing

Amlogic does not provide sources for the firmware and tools needed to create a bootloader image so it is necessary to obtain binaries from sources 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

$ DIR=odroid-n2
$ git clone --depth 1 https://github.com/hardkernel/u-boot.git -b odroidn2-v2015.01 $DIR

$ cd odroid-n2
$ make odroidn2_defconfig
$ make
$ export UBOOTDIR=$PWD

Go back to the mainline U-Boot source tree then:

$ mkdir fip

$ wget https://github.com/BayLibre/u-boot/releases/download/v2017.11-libretech-cc/blx_fix_g12a.sh -O fip/blx_fix.sh
$ cp $UBOOTDIR/build/scp_task/bl301.bin fip/
$ cp $UBOOTDIR/build/board/hardkernel/odroidn2/firmware/acs.bin fip/
$ cp $UBOOTDIR/fip/g12b/bl2.bin fip/
$ cp $UBOOTDIR/fip/g12b/bl30.bin fip/
$ cp $UBOOTDIR/fip/g12b/bl31.img fip/
$ cp $UBOOTDIR/fip/g12b/ddr3_1d.fw fip/
$ cp $UBOOTDIR/fip/g12b/ddr4_1d.fw fip/
$ cp $UBOOTDIR/fip/g12b/ddr4_2d.fw fip/
$ cp $UBOOTDIR/fip/g12b/diag_lpddr4.fw fip/
$ cp $UBOOTDIR/fip/g12b/lpddr4_1d.fw fip/
$ cp $UBOOTDIR/fip/g12b/lpddr4_2d.fw fip/
$ cp $UBOOTDIR/fip/g12b/piei.fw fip/
$ cp $UBOOTDIR/fip/g12b/aml_ddr.fw fip/
$ cp u-boot.bin fip/bl33.bin

$ sh fip/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

$ sh fip/blx_fix.sh \
     fip/bl2.bin \
     fip/zero_tmp \
     fip/bl2_zero.bin \
     fip/acs.bin \
     fip/bl21_zero.bin \
     fip/bl2_new.bin \
     bl2

$ $UBOOTDIR/fip/g12b/aml_encrypt_g12b --bl30sig --input fip/bl30_new.bin \
                                      --output fip/bl30_new.bin.g12a.enc \
                                      --level v3
$ $UBOOTDIR/fip/g12b/aml_encrypt_g12b --bl3sig --input fip/bl30_new.bin.g12a.enc \
                                      --output fip/bl30_new.bin.enc \
                                      --level v3 --type bl30
$ $UBOOTDIR/fip/g12b/aml_encrypt_g12b --bl3sig --input fip/bl31.img \
                                      --output fip/bl31.img.enc \
                                      --level v3 --type bl31
$ $UBOOTDIR/fip/g12b/aml_encrypt_g12b --bl3sig --input fip/bl33.bin --compress lz4 \
                                      --output fip/bl33.bin.enc \
                                      --level v3 --type bl33 --compress lz4
$ $UBOOTDIR/fip/g12b/aml_encrypt_g12b --bl2sig --input fip/bl2_new.bin \
                                      --output fip/bl2.n.bin.sig
$ $UBOOTDIR/fip/g12b/aml_encrypt_g12b --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 \
                                      --ddrfw1 fip/ddr4_1d.fw \
                                      --ddrfw2 fip/ddr4_2d.fw \
                                      --ddrfw3 fip/ddr3_1d.fw \
                                      --ddrfw4 fip/piei.fw \
                                      --ddrfw5 fip/lpddr4_1d.fw \
                                      --ddrfw6 fip/lpddr4_2d.fw \
                                      --ddrfw7 fip/diag_lpddr4.fw \
                                      --ddrfw8 fip/aml_ddr.fw \
                                      --level v3

Then write U-Boot to SD or eMMC with:

$ DEV=/dev/boot_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=440