Suspend for the "Thinkpad X1 Carbon (6th Gen)" on Linux

Unfortunately the ThinkPad X1 Carbon (6th Gen) aka (X1C6 and X1 Carbon 2018) does not support suspend on Linux. There's an ongoing discussion in the Lenovo Support Forums. With some help from the Arch Linux Community, I was able to create an ACPI override for the DSDT. This enables full support of S3 suspend on Linux.

Prerequisites

Debian/Ubuntu based distro with initramfs-tools based initramfs generation for fully automated setup apart from the BIOS related things.

For other distros there are some further steps needed. (PRs welcome)

(Optional) BIOS version

The current BIOS version for the X1C6 is 1.25. You can download the update ISO from the Lenovo Support Site.

BIOS update

If you wanna update via USB drive use geteltorito.

geteltorito -o x1c2018-125.img n23ur08w.iso
sudo dd if=x1c2018-125.img of=/dev/sdX bs=512K

Reboot from USB and follow instructions.

BIOS settings

Set Thunderbolt BIOS Assist Mode to Enabled (via Config → Thunderbolt 3).
(Unconfirmed): Disable Secure Boot.

If you see all three lines in dmesg | grep -A3 'DSDT ACPI'

[    0.000000] ACPI: DSDT ACPI table found in initrd [kernel/firmware/acpi/dsdt.aml][0x2338b]
[    0.000000] Lockdown: ACPI table override is restricted; see man kernel_lockdown.7
[    0.000000] ACPI: kernel is locked down, ignoring table override

rather than just the first line, disable Secure Boot

Tools

Make sure that you have iasl (via acpica) and cpio (via cpio) installed.

Installed automatically on distros with apt such as Debian/Ubuntu

Generating the override

curl -O https://raw.githubusercontent.com/fiji-flo/x1carbon2018s3/master/generate_and_apply_patch.sh
chmod +x generate_and_apply_patch.sh
./generate_and_apply_patch.sh

Loading the override on boot

Edit your boot loader configuration and add /acpi_override to the initrd line. To ensure S3 is used as sleep default add mem_sleep_default=deep to you kernel parameters.

If you're using systemd-boot your /boot/loader/entries/arch.conf might look like this:

title		Arch Linux ACPI
linux		/vmlinuz-linux
initrd		/intel-ucode.img
initrd		/acpi_override
initrd		/initramfs-linux.img
options		root=/dev/nvme0n1p2 rw i915.enable_guc=3 mem_sleep_default=deep

Other boot loaders

If you made it work with other boot loaders please help out (PRs are most welcome).

Some notes

/acpi_override must be specified before /initramfs….
When using a single partiion try using /boot/acpi_override instead of acpi_override. Use the same prefix (if any) used by the existing /prefix/initramfs-linux.img parameter.

Verify that it's working

After rebooting check the output of:

dmesg | grep -i "acpi: (supports"

should look like this:

[    0.230796] ACPI: (supports S0 S3 S4 S5)

kenanpelit/x1carbon2018s3