Gentoo on the X205TA 2021-01-14

I’ve had an ASUS X205TA for a few years now, and installed Lubuntu on it initially, as it was practically unusable with Windows 10 after installing a few programs. Lubuntu was great and all for me while I was just starting to use to Linux more often, and it worked fine for doing schoolwork. Just recently I felt like it was time to do a clean install of something on there. I was initially thinking of going with Arch, but I figured I’d get a bit adventurous and try something different (already running Arch on two other machines). I thought, “Maybe I should try out Gentoo!” This was my first time installing Gentoo—it was also probably the most painful Linux install I’ve ever put myself through! (not because of Gentoo, but because of the device hardware).

If you’ve done any searching online for guides or helpers on installing Gentoo specifically on this laptop, you’ve probably realised already that there’s almost no information whatsoever. You can find info for other distros which doesn’t all apply since there’s so much manual work required in a Gentoo installation. There’s one article by some Japanese guy which when translated has some useful stuff in it. The guy was close to getting it to work on his X205TA, but ran into the same issues that I did; kernel panics while booting, and an unusable keyboard when it actually did boot. After hours of tweaking with the kernel configuration, I managed to get the system to run real nicely. I still haven’t run into any issues, freezes or anything, which is great!

I thought I’d write this little guide to help any of the other people pulling their hair out trying to install Gentoo on this system. This is not a “full installation” per se, but rather a set of extra/notable steps that need to be taken on this device. I’d recommend having this guide on the side as you follow the official guide.

Let me just warn you now—compilation of large packages on this device will usually take quite a while. If I were you I’d definitely try avoiding installing any massive desktop environments, and instead take a minimal approach, with a standalone window manager, etc.

Oh, and a little disclaimer: do this at your own risk. I’m not at fault if you screw up your laptop!

Getting started

If you’ve installed Linux on an X205TA before, you’re probably already aware that the device has a 64-bit CPU, and must have an exclusively 32-bit bootloader (if you didn’t know that before you’re probably wondering why this is the case; the reason is actually because ASUS are a pack of idiots). Gentoo’s Live 64-bit CD ISO already comes with a 32-bit bootloader on it, so you’re able to just burn it to a USB stick, plug it in, and boot right into the live environment.

Wi-fi should work out of the box. Hop into wpa_supplicant and get yourself connected. If for whatever reason you cannot connect, try run modprobe brcmfmac to manually load the Wi-fi module.


The X205TA uses an eMMC as it’s storage device (basically an SD card). Linux identifies it as /dev/mmcblkX and its partitions as /dev/mmcblkpXpX.

I partitioned my drives as below using parted:

  mmcblk1p1   130M   /boot/EFI
  mmcblk1p2    29G   /			

Since this is a UEFI system, we need to create an ESP (EFI System Partition), which is mmcblk1p1 in my case. Make sure you also set the ESP to be bootable! It should have both the ’boot’ and ’esp’ flags when you run the print command in parted.

If your lsblk output includes a bunch of other block devices, like mmcblk1boot0 or something, just ignore them. I didn’t use these at all and had no idea where they came from honestly. You might be able to delete them if you want (though I’m not sure if it’ll cause problems).

You can optionally create a separate /boot partition if you want. I decided not to do this just to keep shit simple.

Note: the X205TA only has 2 GiB of RAM onboard. You will need some kind of swap space on the system to compile some of the larger packages or else you will run out of RAM and portage will abort the compilation process (happened to me twice while compiling GCC). You can create a swap partition if you like. I personally created a 2 GiB swapfile, however you can use as much as you like.

As for filesystems. The ESP must also be formatted as a FAT filesystem, so:

mkfs.fat -F 32 /dev/mmcblk1p1			

You can of course use EXT4 for your root partition.

Make sure that you mount all the partitions and swapon your swap space when you chroot into the system (use the method provided in the install guide). If you’re partitioning the same way as me, make sure you use the same mount points I specified above.

Setting up the make.conf

You should be able to get away with using MAKEOPTS="-j3" for building most of the packages on the system (be careful when compiling large packages like GCC though. If you have too many jobs then you will end up writing a lot to swap instead of RAM which will make compilation very slow).

Other things you will want to put in your make.conf:

# 'synaptics' is for touchpad support
INPUT_DEVICES="libinput synaptics"
# X205TA has Intel graphics onboard
VIDEO_CARDS="intel i965"			

You can also add the following CPU flags to it, I generated these using cpuid2cpuflags. If you want to be absolutely certain that these are correct for your hardware, emerge cpuid2cpuflags and run it yourself.

CPU_FLAGS_X86="aes mmx mmxext pclmul popcnt rdrand sse sse2 sse3 sse4_2 ssse3"			

Finally, and this is probably one of the most important settings; like I mentioned earlier, the X205TA has an exclusively 32-bit bootloader. Make sure you put this in your make.conf if you want your machine to boot:


Kernel configuration

Okay. This is another important part; it’s also where it gets pretty messy. There are a bunch of kernel options that must be included in order for your system to function properly. These should be all the important ones. If you think anything is missing, feel free to contact me and I’ll correct it. I’ve also probably included more options than necessary here—I don’t really have the time to test every option individually, so I just went with whatever worked. If you think any of the options are completely unnecessary, just let me know and I’ll remove it from here.

If you don’t want to configure your kernel yourself (or if you can’t get your system to work properly), you can try using my config instead (no sound support), given that you are also running something around kernel 5.4.80.

eMMC support

Make sure you’ve got all of these in your config, or else you will get kernel panics at boot time.

Device Drivers
  MMC/SD/SDIO card support
    <*> MMC block device driver
    <*> Secure Digital Host Controller Interface support
    <*>   SDHCI support on PCI bus
    [*]     Ricoh MMC Controller Disabler
    <*>   SDHCI support for ACPI enumerated SDHCI controllers
    <*>   SDHCI platform and OF driver helper
    <*> MMC/SD driver for Ricoh Bay1Controllers			

Pin Controller

Device Drivers
  Pin controllers
    [*] Intel Baytrail GPIO pin control
    [*] Intel Cherryview/Braswell pinctrl and GPIO driver			


Thanks to the Japanese guy I mentioned earlier for mentioning these options. However we also need to include the WLAN driver so we can enable the wlan0 interface. (Note that these are in addition to the other base options that you’d normally use for networking).

Device Drivers
  Wireless LAN
    [*] Broadcom devices
    <M>   Broadcom 43xx wireless support (mac80211 stack)
    [*]   Broadcom 43xx SDIO device support
    <M>   Broadcom FullMAC WLAN driver
    [*]   SDIO bus interface support for FullMAC driver
Networking Support
  <M> cfg80211 - wireless configuration API
  [*]   enable powersave by default
  [*]   cfg80211 wireless extensions compatibility
  <M> Generic IEEE 802.11 Networking Stack (mac80211)
  [*] Export mac80211 internals in DebugFS			


The following need to be built into the kernel to get the keyboard working. Thanks to harryharryharry over at Ubuntu forums for mentioning the I2C stuff (and for all of his contributions to getting Linux working on this laptop!)

Device Drivers
  HID support
    I2C HID support
      <*> HID over I2C transport layer
  I2C support
    I2C Hardware Bus Support
      <*> Synopsys DesignWare Platform
      [*]   Synopsys DesignWare Slave
      <*> Synopsys DesignWare PCI
      [*] Intel Baytrail I2C semaphore support
  Input device support
    <M> Mouse interface
    <M> Event interface
    [*] Keyboards
    <M>   (basically all keyboards)
    [*] Mice
    <M>   ELAN I2C Touchpad support
    [*]     Enable I2C support
    [*]     Enable SMbus support
    <*>   Synaptics I2C Touchpad support			


Device Drivers
  Graphics support
    <*> Intel 8xx/9xx/G3x/G4x/HD Graphics
    [*] Enable capturing GPU state following a hang.
    [*]   Compress GPU error state
    [*] Always enable userptr support			


I’m adding this section after the original post date (currently 2020-01-22). I haven’t tried getting sound working on the 5.4 kernel, as I’m now running the latest stable 5.10.9 kernel. You can try reproduce the settings below on an older kernel, I don’t know if it’ll work though.

These should be all the options you need to get the sound working decently. There will be just a slight hiss in the headphone output but I’m sure you can live with that. Oh, and you will also need to manually switch the output from Headphones to Speakers and vice-versa, using e.g. pavucontrol. You could probably set up some kind of output-toggle binding to speed up that process.

Device Drivers
  <*> Sound card support
    <*> ALSA
      [*] PCI sound devices
      <M> HR-timer backend support
          <M> HD Audio PCI
          [*] Build hwdep interface for HD-audio driver
          [*] Support initialization patch loading for HD-audio
          <M> Build Realtek HD-audio codec support
          <M> Build Analog devices HD-audio codec support
      (4096) Pre-allocated buffer size for HD-audio driver
      <*> ALSA for SoC audio support
        [*] Intel ASoC SST drivers
        <*>   ACPI HiFi2 (Baytrail, Cherrytrail) Platforms
        -*- Intel Machine Drivers
          <M> (everything)
        [*] Sound Open Firmware Support
          <*> SOF ACPI enumeration support.
          [*] SOF support for Intel audio DSPs
        <M> ASoC Simple sound card support			

I have no idea if the microphone will work with these options. I don’t really care since I don’t use the microphone.

And from here all the other kernel options (USB support, etc) should be pretty generic and obvious.

Kernel patches

If you want to squeeze as much performance as possible out of your X205TA, you can apply the linux-ck performance patches to your kernel. I’m running this personally and it seems to just make the system feel a bit snappier overall.

GRUB installation

To install GRUB we have to run these two commands. Make sure you do not include a partition number in the grub-install command (e.g. don’t use mmcblk1pX) or else your laptop won’t boot (at least in my testing). As long as the /boot/EFI directory exists (and you’ve formatted partitions the same as me), the below commands will install the bootloader just fine.

grub-install --target=i386-efi /dev/mmcblk1
grub-mkconfig -o /boot/grub/grub.cfg			

Your bootloader should now appear in /boot/EFI/EFI/gentoo. It probably looks weird with the two EFI directories, but it seems to work perfectly like this.

I also created an initramfs. I’d say you should probably install one of these too on your machine:

genkernel --install --kernel-config=/usr/src/linux/.config initramfs			

Finishing up

And that’s about it! If all went well—you followed the official install Gentoo instructions and applied the stuff from this guide, you should hopefully be able to unmount everything, reboot, and boot into a fresh Gentoo installation on your X205TA! You’re on your own from here to decide how the rest of your system will be laid out.

If you have any questions, comments, or problems with the information here, please feel free to e-mail me via the address on my homepage.

Have fun waiting for all your packages to compile ;)