SteamDeck_rEFInd
This is a simple rEFInd install script for the Steam Deck meant to provide easy dual boot setup when using both SteamOS and Windows on the internal NVMe.
This simple install script assumes that the SteamOS and Windows boot entries are valid and have not been renamed (folders have correct names as well). If you've followed a guide telling you to rename any EFI files or folders, please revert those changes before running this script. The icons can be replaced with any 128x128 icons that a user desires. Please just make sure to update the refind.conf file for the correct icon names, if deviating from what's provided here. The background can also be any 1,280 x 800 properly formatted picture. Same as with the icons, if you plan to use a different background, make sure you update the applicable line in refind.conf for your background image. I recommend making any changes to the icons or background picture and refind.conf file before running the installation script.
Prerequisites: This installation script assumes that there are valid EFI boot entries for both Windows and SteamOS on the esp partition. For SteamOS there should be a valid EFI boot file located at /esp/efi/steamos/steamcl.efi . For Windows, there should be a valid EFI boot file located at /esp/efi/Microsoft/Boot/bootmgfw.efi . If you are missing either of these, or they do not function as intended, do not proceed with the installation script unless you know how to edit the boot entries in the refind.conf file to point to your correct EFI boot files for the OSes. You can confirm this by pressing Volume Up and Power buttons, then going to boot from file and selecting these manually. They should boot correctly into their respective OSes, otherwise do not proceed with the installation script (or proceed at your own risk).
Assuming you have the 2 valid SteamOS and Windows EFI boot files, continue and run the following steps for installation.
Basic Installation instructions (assuming from a SteamOS command line in desktop mode). Run these commands one after the other.
git clone https://github.com/jlobue10/SteamDeck_rEFInd/
cd SteamDeck_rEFInd
chmod +x SteamDeck_rEFInd_install.sh
./SteamDeck_rEFInd_install.sh
If all went well, you should have rEFInd setup with SteamOS as the default loading OS. Feel free to adjust the timeout from 5 seconds to whatever desired value in the refind.conf file. This is how long you will have to choose your OS before the default OS loads. Select the desired OS using the right trackpad and the R2 (trigger) button.
Extra information and considerations If you plan on reinstalling Windows after running this script, you will need to disable the rEFInd EFI boot entry beforehand so that rEFInd does not interfere with the Windows installation process. You can do this from SteamOS desktop mode in a command line with two steps.
efibootmgr
Take note and remember the boot entry for rEFInd and replace XXXX below with that number.
sudo efibootmgr -b XXXX -A
SteamOS branch considerations
When using SteamOS branches other than the Stable branch, it's possible to run into some issues preventing a successful run of the script and installation of rEFInd. My recommendation for setting up any Steam Deck would be to always have Windows and SteamOS (Stable branch) both setup and working before the initial run of the script. If you try to change to any SteamOS branch other than Stable before the first run of the rEFInd installation script, the step where the Windows EFI boot entry is disabled may not complete successfully and therefore rEFInd will not be able to work. For this reason, run the script from the SteamOS Stable branch first before switching away from the Stable branch. In addition, a new issue popped up with SteamOS 3.4 where you may have to manually boot SteamOS from its EFI boot file, in order to run the rEFInd installation script one more time to restore rEFInd.
Additional Windows considerations (corrupted display on boot into Windows)
If you encounter an issue while booting up where the Windows display is corrupted to the point that it's basically unusable, there is a workaround to fix the issue. Boot into SteamOS and edit the refind.conf file using the commands sudo steamos-readonly disable then sudo nano /esp/efi/refind/refind.conf from a command line. Make sure all resolution lines are commented out in the refind.conf config file (line begins with a #). When this is done, press Ctrl+x followed by y to save and exit. If this is successful, then on next reboot, the rEFInd screen will be rotated in portrait mode. Boot into Windows, fix any resolution discrepancies (should be 1,280 x 800 for main Steam Deck display) and save those changes. You should now be able to go back into SteamOS, edit the refind.conf config file again and make sure that resolution 3 is uncommented (# at line beginning deleted) for use. Once you've confirmed normal operation again, please use the sudo steamos-readonly enable command from a SteamOS command line.
References