Juan Francisco Cantero Hurtado wrote:
> Slightly off-topic:
>
> Ubiquiti released recently a new router named EdgeRouter X. 49 USD, 5
> gigabit ports, 5W, dual-core 800Mhz, 256MB.
>
> It's a MIPS32, so if some developer is looking for a new platform for
> OpenBSD... :P . The processor is licensed from Imagination, which I
> guess that is more open than Cavium. I have not found a dmesg yet.
>
> http://dl.ubnt.com/datasheets/edgemax/EdgeRouter_X_DS.pdf
>
> http://www.embeddeddeveloper.com/cores/documents/MIPS32_1004K_rev1.pdf
This spring, I asked a few OpenBSD MIPS devs about the project's
interest in a MIPS32 port for the Creator CI20. It turns out that MIPS32
support was quietly removed last year:
> ----------------------------
> revision 1.20
> date: 2014/03/11 07:50:49; author: jasper; state: Exp; lines: +1 -15;
> remove #if(n)def __LP64__ from the mips64 codebase, as mips32 never really
> went anywhere.
>
> ok miod@
> ----------------------------
I was pretty forcibly told that there was no interest, which is
understandable. Without TLB magic or the below-mentioned EVA, a MIPS32
chip can only directly map 512 MB of memory, which is becoming
unacceptable for everything but embedded devices. For more details,
check out its wacky memory model:
http://www.johnloomis.org/microchip/pic32/memory/memory.html
ImgTec, the new owners of the ISA, added a workaround called Enhanced
Virtual Addressing (EVA) in MIPS32 revision 3.5 (MIPS32r3.5). It
increases the directly mapped memory limit to 3.5 GB. I don't know
whether any OSs actually support it, though, and I remember hearing that
it's not elegant (but that's just a vague memory).
My description of the memory limit issue may have been misleading. If
anyone notices mistakes, please correct me. :)
So, if you want BSD on MIPS32, NetBSD is your best (only?) bet.
