- Amlogic S905X SoC
- 4x ARM Cortex-A53 CPU
- ARM Mali-450 GPU
- 2 GB RAM
- 8/16 GB eMMC
- 40-pin GPIO connector (not Raspberry Pi compatible)
Khadas VIM board is supported in official U-Boot since version v2018.01-rc1. Current version (v2019.01) support boot from eMMC and SD card.
A u-boot-khadas-vim package is available.
To be able to create a bootable image in OBS, aml_encrypt_gxb tool (available on GitHub) should be modified to support S905X SoC.
Please note that your SD card or eMMC must use MBR partitions (not GPT).
GRUB2 works with the EFI boot stack available in U-Boot.
openSUSE Tumbleweed installation using standard DVD
With TW and with the EFI boot protocol implemented in U-Boot, it is possible to directly install from DVD image on Khadas VIM.
Note this guide assumes:
- that you already have a Leap/Tumbleweed OS installed on your PC
- that you are familiar with the openSUSE installation procedure
To boot the DVD there are multiple ways:
- burning the ISO on a USB key
- booting the ISO through the network boot (PXE)
For each cases, it is still needed to use a SD card or USB key to load U-Boot (SD card is the preferred way).
The USB key method will be used here (with U-Boot on the SD card).
Graphical/textmode installation through HDMI partially works, but some issues can happen, so it is recommended to use textmode ssh installation if possible. Also, U-Boot shell is only accessible through serial console at that time.
Note: To be able to execute U-Boot from eMMC you need to use MBR disk scheme instead of the default GPT scheme. To do this you "simply" need to do a custom disk configuration. Or you can use a small SD card and put U-Boot on it, S905X SoC will boot on it if no bootloader is found on SPI/eMMC. So with this you can keep the default GPT partition scheme.
- Download the Tumbleweed ISO and "burn" it on the USB key - WARNING all previous data on the device will be lost!
# dd if=[image].iso of=/dev/<usb_key> bs=4M iflag=direct,fullblock oflag=direct
- Insert the SD card and USB key into your board
- Connect the board to your PC via serial port (recommended; USB-TTL serial cable needed)
- Connect the board to your monitor (via DVI/HDMI, optional if you use the serial port)
- Power on the board
- Stop the U-boot procedure by pressing a key
- Force boot on the USB key
Hit any key to stop autoboot: 0 => run usb_boot
- Some parameters need to be set for installation, so you have to edit the boot option on GRUB and add the following options:
earlycon=meson,0xc81004c0 console=ttyAML0,115200 ssh=1 sshpassword=linux
- Some optional parameters are also useful:
elevator=noop # complex scheduling is not needed on flash drive splash=verbose # can be useful to have all systemd messages on the console
- Your board is now booting the installation DVD!
- Connect to the board throught SSH and execute the installer (DISPLAY= is here to force textmode for YaST):
# DISPLAY= yast.ssh
- Adapt your disk configuration if needed (GPT vs. MBR), normal installation is then expected!
- If you want to install U-Boot on the eMMC please pause the installation at the end before rebooting (Stop option) and follow the U-Boot installation on eMMC procedure
Note: after installation the serial console is by default reset to ttyAMA0, so you need to set it to ttyAML0 again in /etc/defaut/grub (don't forget to re-generate grub.cfg file after!).
U-Boot installation on eMMC
After OS installation if you want to have U-Boot installed on the eMMC as well you just have to burn the u-boot.bin file in the "MBR gap":
dd if=u-boot.bin of=/dev/mmcblk1 bs=512 seek=1
And then reboot your board without any SD card/USB key. U-Boot should be loaded directly from eMMC. After this boot from SD card is not possible anymore!
If you first want to clean the previously installed U-Boot, or if you want to force boot on SD card, you could erase the "MBR gap":
dd if=/dev/zero of=/dev/mmcblk1 bs=512 seek=1 count=2047