Notes from attempting to sys-mode Alpine Linux on the Raspberry Pi 4

A quick-and-dirty set of notes that perhaps will become a real essay in the future:

Installing Alpine Linux sysmode (that is, directly on the disk unlike the traditional load-to-RAM approach) on the Pi is... complicated. The whole thing ultimately feels like a hack and there's always a lingering sensation that you might mess something up and have to start all over from scratch. There's a very complete guide available on the Alpine wiki, thankfully, but even then some of the steps don't always work one-to-one. The overall procedure is summarized as follows:

• Partition the SD card in two: a small (300MB or so) FAT-16 partition to "boot" the installer files and have the setup ready, and the remainder of the card into Ext4 to actually hold the sysmode installation.
• Extract the Alpine tarball in the installer partition.
• Boot the SD card into the Pi and run the setup-alpine installer more or less normally. Choose yes to install in the installer media when prompted (the installer is smart enough to figure out there's a larger, empty partition that it can use).
• Move the boot contents from your tiny "boot" partition to the persistent partition, telling the config files (cmdline.txt, etc) where to find the booting-related stuff and mount the partition automatically.
• Reboot and rejoice for you have full persistence...

Except that you still need to configure your desktop (Xorg drivers where?) and the other stuff and in the end, the Pi is still throttled down to 600MHz when idle! Oh well, leave to further investigation in the future...!