Something I'd be very interested in seeing summarized is the current state of fully open source software on SoCs and SBCs. I hate how common the situation described in the nVidia section where SoCs that require vendor kernels get abandoned on ancient software, so it would be very useful to know what SoCs are supported to a useful level by mainline kernels.
I feel like there are three tiers of support that most people would be interested in:
1. Usable for headless appliances (serial console or unaccelerated graphics, wired networking, storage, USB)
2. Usable for interactive use (accelerated graphics, WiFi/BT)
I'm guessing this is why, as others have already mentioned, there seems to be an increase in use of x86 processors like the N100. You don't need to worry about stuff like specific vendor kernels.
yeah, x86 BIOS/UEFI plus VESA provides for a not-great but decently usable foundation. Easy enough to hand-code a hello world in assembly - good luck trying to do that one on any ARM system.
If you are talking bare metal rather than Linux support, many M-core MCUs are easy, and some of these (e. g. STM32H7) actually have usable 1995-level desktop performance sans MMU, ergo enough for many things that aren't web browsing. It's A-cores that's closed, because vendors have zero incentives to open them up and because the whole thing is a heap of Synopsys modules ducktaped together - and Synopsys has an less incentive to open up. And then of course, there are GPUs, that's not well supported even on x86. Video out - yes, you get it with UEFI GOP, but usually no multihead. You also get it on many ARM SoCs - the video output generator is sometimes documented, it's accelerator/compute that's universally closed.
It's always possible to just go to dts directory in latest Linux kernel, and just look for what's enabled on SoC or board level, for a quick apprisal of level of mainline support.
You will not catch all the details this way, drivers may be incomplete, or things may not be fully integrated to work together really well, but then that's usually fixable, especially if datasheets are available.
Well, a 5-year-old chip may not count as "recent" but the RK-3588 boot chain is "almost fully open-source" [1]. And it seems like it took a major amount of effort (from Collabora, others) to get it this far. I don't know of any equivalent or newer chips that are "more" open, but would love to hear if there are.
I agree having this info more plainly available would be great, but in the interim interested folks can take a look at postmarketos device support, collabora blogs, and the pine64 wiki to get some of this info.
I feel like there are three tiers of support that most people would be interested in:
1. Usable for headless appliances (serial console or unaccelerated graphics, wired networking, storage, USB)
2. Usable for interactive use (accelerated graphics, WiFi/BT)
3. Fully supported (all major hardware works)