ARM is great, ARM is terrible (and so is RISC-V)
I’ve long been interested in new and different platforms. I ran Debian on an Alpha back in the late 1990s and was part of the Alpha port team; then I helped bootstrap Debian on amd64. I’ve got somewhere around 8 Raspberry Pi devices in active use right now, and the free NNCPNET Internet email service I manage runs on an ARM instance at a cloud provider.
ARM-based devices are cheap in a lot of ways: they use little power and there are many single-board computers based on them that are inexpensive. My 8-year-old’s computer is a Raspberry Pi 400, in fact.
So I like ARM.
I’ve been looking for ARM devices that have accelerated AES (Raspberry Pi 4 doesn’t) so I can use full-disk encryption with them. There are a number of options, since ARM devices are starting to go more mid-range. Radxa’s ROCK 5 series of SBCs goes up to 32GB RAM. The Orange Pi 5 Max and Ultra have up to 16GB RAM, as does the Raspberry Pi 5. Pine64’s Quartz64 has up to 8GB of RAM. I believe all of these have the ARM cryptographic extensions. They’re all small and most are economical.
But I also dislike ARM. There is a terrible lack of standardization in the ARM community. They say their devices run Linux, but the default there is that every vendor has their own custom Debian fork, and quite likely kernel fork as well. Most don’t maintain them very well.
Imagine if you were buying x86 hardware. You might have to manage AcerOS, Dellbian, HPian, etc. Most of them have no security support (particularly for the kernel). Some are based on Debian 11 (released in 2021), some Debian 12 (released in 2023), and none on Debian 13 (released a month ago).
That is exactly the situation we have on ARM. While Raspberry Pi 4 and below can run Debian trixie directly, Raspberry Pi has not bothered to upstream support for the Pi 5 yet, and Raspberry Pi OS is only based on Debian bookworm (released in 2023) and very explicitly does not support a key Debian feature: you can’t upgrade from one Raspberry Pi OS release to the next, so it’s a complete reinstall every 2 years instead of just an upgrade. OrangePiOS only supports Debian bookworm — but notably, their kernel is mustly stuck at 5.10 for every image they have (bookworm shipped with 6.1 and bookworm-backports supports 6.12).
Radxa has a page on running Debian on one specific board, they seem to actually not support Debian directly, but rather their fork Radxa OS. There’s a different installer for every board; for instance, this one for the Rock 4D. Looking at it, I can see that it uses files from here and here, with custom kernel, gstreamer, u-boot, and they put zfs in main for some reason.
From Pine64, the Quartz64 seems to be based on an ancient 4.6 or 4.19 kernel. Perhaps, though, one might be able to use Debian’s Pine A64+ instructions on it. Trixie doesn’t have a u-boot image for the Quartz64 but it does have device tree files for it.
RISC-V seems to be even worse; not only do we have this same issue there, but support in trixie is more limited and so is performance among the supported boards.
The alternative is x86-based mini PCs. There are a bunch based on the N100, N150, or Celeron. Many of them support AES-NI and the prices are roughly in line with the higher-end ARM units. There are some interesting items out there; for instance, the Radxa X4 SBC features both an N100 and a RP2040. Fanless mini PCs are available from a number of vendors. Companies like ZimaBoard have interesting options like the ZimaBlade also.
The difference in power is becoming less significant; it seems the newer ARM boards need 20W or 30W power supplies, and that may put them in the range of the mini PCs. As for cost, the newer ARM boards need a heat sink and fan, so by the time you add SBC, fan, storage, etc. you’re starting to get into the price range of the mini PCs.
It is great to see all the options of small SBCs with ARM and RISC-V processors, but at some point you’ve got to throw up your hands and go “this ecosystem has a lot of problems” and consider just going back to x86. I’m not sure if I’m quite there yet, but I’m getting close.
