Asus T100 TA with Linux

This document/repository is inspired by 5bentz's linux-asus-t100 guide

The Asus T100 TA has a 64-bit CPU with a 32-bit UEFI/BIOS and thus needs some extra steps to work with many Linux distributions/their GRUB configuration.

The steps in this guide are for installing Linux Mint 21.3 Cinnamon 64-bit, but may work with other versions and distros.

Pre requirements

• A USB flash drive (>=3 GB)
• The Linux Mint 21.3 iso
• bootia32.efi src1, src2 (files might be unsafe, compile them yourself)
• grubia32.efi src1, src2 (files might be unsafe, compile them yourself)
• An Asus T100 TA (duh!)
• This guide (on a second device/printed or memorized)

Preparing the installation media

Use a tool like Rufus, balena etcher, dd ... or copy the iso to a USB flash drive with Ventoy installed.

Install Linux Mint

Press/spam Esc for the boot-menu and F2 for the UEFI-Setup

Disable Secure Boot, then boot from the USB flash drive and install the system like you normally would.

If you run into problems during the installation, try connecting your device to the internet before starting the installer.

After the intaller finishes, open a terminal and type:

sudo -s
mount /dev/<device name>p<boot partition num> /mnt
pushd /mnt/EFI/Boot
wget -o bootia32.efi <bootia32.efi url> | sha512sum  # sha512:d493701aaa5cdf57eb35a22c198d496fc3d7295bd763f17b7cb2edba3e4b9939391e18b2cd808564bc14e4076d3559f3b598230db42b490cf48d9133febd8bc4
  # or copy the previously downloaded file

Take note of the device name (typically mmcblk0 or mmcblk1) and partitions where root and efi are mounted.

First boot

Get a GRUB shell

Select the USB flash drive again, but when the GRUB menu comes up, press c.

You should now be in a GRUB shell.

During your very first boot you might get dropped into a GRUB shell and don't need the USB flash drive at all.

Boot Linux

To start our already installed Linux, type the following into the shell:

configfile (hd<device num>,gpt<root partition num>)/boot/grub/grub.cfg

Or do it manually:

You can press tab to display all options (e.g. for hd, gpt, vmlinuz and initrd)

Mint might also boot when using vmlinuz and initrd.img. The video and reboot arguments might be optional as well.

set prefix=(hd<device num>,gpt<root partition num>)/boot/grub
set root=(hd<device num>,gpt<root partition num>)
linux /boot/vmlinuz-xxx root=/dev/<device name>p<root partition num> video=VGA-1:1368x768e reboot=pci,force
initrd /boot/initrd.img-xxx
boot

Linux Mint should now start

Switch GRUB to 32-bit

1. Connect to the internet

2. Open a terminal (CTRL+ALT+T) and type:

   sudo apt update
   sudo apt install grub-efi-ia32-bin  # might not be necessary
   sudo grub-install --efi-directory /boot/efi  # might not be necessary
     # sources say you also need grub-efi-ia32, but apt reports some dependency error
   sudo -s
   pushd /boot/efi/EFI/ubuntu/
   mv grubx64.efi grubx64.efi.bak
   wget -o grubia32.efi <grubia32.efi url> | sha512sum  # cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e
     # or copy the previously downloaded file
   update-grub
   update-grub2
   reboot

3. You should now be able to boot Linux Mint without the USB flash drive

   If it does not work and you see two ubuntu entries in the boot menu, try selecting the other one.

Sources

• https://github.com/5bentz/linux-asus-t100/

• https://unix.stackexchange.com/questions/206274/how-do-i-repair-grub2-not-booting-32-bit-efi-on-a-64-bit-machine

• https://linuxnorth.wordpress.com/2014/12/11/installing-64-bit-linux-on-the-asus-transformer-book-t100/

• http://www.jfwhome.com/2014/03/07/perfect-ubuntu-or-other-linux-on-the-asus-transformer-book-t100/