I've just got done fighting to get Devuan on my new laptop, and I thought I'd share some of the things that were necessary to get a working system.

The XPS 15 9570 is a new (as of Aug 2018) Coffeelake-based laptop. As such, it's got a lot of new hardware in it, and a couple of "gotchas".

INSTALLATION:

Devuan ASCII installs in UEFI mode just fine - but you'll find that it won't boot afterwards. Moreover, you will find that this laptop won't boot an MBR-based install at all from the internal /dev/nvme drive at all!

The Devuan install process apparently does not write some critical EFI information that "registers" the Devuan EFI boot binary with the bios, so we have to add it by hand.

1) Write the Devuan ASCII iso to a flash drive. Insert the flash drive, and mash F12 on startup - this will bring you to a boot menu. Choose the *2nd* partition on your flash drive, under the UEFI partitions to boot.

2) When the Devuan installer screen pops up, be sure to choose the UEFI install. The graphical install works just fine, but you'll find that the mouse doesn't work. Oh well.

3) Follow the basic prompts to install. When you get to the partitioner, you will need *at least* the following partitions, in order:

a) a 500MB FAT32 partition, for EFI
b) a swap partition (I used 8GB)
c) a partition for / (I used a 30GB partition, ext4)

OPTIONAL: I usually keep /home on a separate partition. I would recommend using the mount options of "discard, noatime" on /, and /home (if yours is separate)

4) Go through the rest of the install. A word of caution: If you like using the Cinnamon desktop, as I do, avoid it at this time on this laptop - it's crashy, and can't seem to run the compositor in hardware mode. I defaulted to LXqt, and then installed Budgie later. I will note that the install process complains about missing firmware for the Killer Wireless (ath10k), but wireless works anyway.

BIOS:

5) When the install finishes, and the laptop reboots, mash F12 again, and go into the BIOS setup. You're going to want to go into the UEFI setup, and add a UEFI boot selection. This is the part that seems to work automatically for Ubuntu, but not for Devuan. If you have just one boot option, as I do, the menu will list your EFI partition. At the bottom of this screen, you'll be able to "browse" to the EFI/devuan/grubx64.efi, and give the boot option a label. I used "Devuan". Once you save this, the laptop will able to boot from this Devuan install!

FIRMWARE:

6) Now that you're in, you'll find that the fan spins up quite a lot, bluetooth is not functional, and *dmesg* reports lots of missing firmware .bin files. We'll fix those.

a) Install Git:

sudo apt-get install build-essential git 

b) Install the following packages:

sudo apt-get install firmware-linux firmware-linux-nonfree firmware-misc-nonfree

c) Clone the firmware tree:

git clone https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/

There are three firmware trees we're interested in here:

./i915
./nvidia
./ath10k/QCA6174

It seems safe to copy in the following firmware trees:

cp -rp i915 /lib/firmware/
cp -rp ath10k/QCA6174 /lib/firmware/ath10k

The nvidia firmware tree seems a mixed bag. The firmware files include missing firmware for gp102 and gp107 that don't currently exist on Devuan ASCII, but I find that the *nouveau* driver gets "explody" if you use them. They might be necessary for the nonfree nVidia drivers, though. Use with caution!

PCI IDs:

The existing PCI Bus ID list is not updated enough for this hardware. If you want to make sense of all those hex ids in *lspci*, update your pci ID list:

 sudo update-pciids 

KERNEL:

The existing 4.9 kernel really doesn't know what to with a lot of the hardware in this machine. We need a newer kernel to take advantage of the hardware here, and as it happens, 4.18.4 seems to run pretty well. Using the excellent guide by batmore here: https://dev1galaxy.org/viewtopic.php?id=564, get the latest stable kernel source, and build a kernel and modules for 4.18.4. I will note that I used gcc-6.

POWER

In an effort to bring down the power usage, I've added the *tlp* package, and installed the Intel Vulkan drivers, and added some options to the i915 driver:

sudo apt-get install mesa-vulkan-drivers

* /etc/modprobe.d/i915.conf * (create if this does not exist):

options i915 enable_fbc=1 enable_guc=3

Before these changes were made, I would hear my laptop fan spin up and down constantly, even when not under load. Now, I am not hearing that at all. The battery meter estimate in Budgie went from a max of 8 hours or so at full charge to 11 hours. YMMV.

4K Displays
I'm using an external 4k display, a Seiki 39" SE39UY04. This is by no means state-of-the-art, but it's a functional 4k display. The monitory seems to work, out-of-the-box, with all the changes I've made above. Sometimes it doesn't get detected correctly, but that seems pretty much par for the course. I just turn it off, and then back on. HiDPI seems to "just work" with MATE.

TODO:

* In MATE, the marco hardware compositor works, but uses significantly more cpu than the software compositor does. I also note that the Cinnamon hardware compositor will not start up. I think the video drivers have to catch up here.
* I haven't tried the optimus video switching at all, yet
* I didn't have much luck with the close-source nVidia drivers, yet.

KNOWN WORKING:

Nostrilcam (webcam)
Bluetooth
USB ports
SD Card reader

NEEDS IMPROVEMENT:

Power management (battery life seems good, but could be better. I'm looking into that.)
Nouveau driver (I don't think the driver works too well on the nVidia GeForce GTX 1050 Ti Mobile yet)
Intel Graphics (I haven't updated this driver either, probably some improvements here as well)

Hopefully someone finds this helpful.