Subject: Re: Sys Install Program
To: None <pnuli@mediaone.net>
From: Kevin Cousins <kevin.cousins@praxa.com.au>
List: tech-install
Date: 08/02/2000 15:00:07
    Prasad> I am trying to put a sysinstall utility for the ARC/MIPS
    Prasad> Port. As Alpha is also a ARC platform ( At least some of
    Prasad> them ). I took the sources from Alpha Sysinstall and
    Prasad> copied them to ARC directoy and compiled the sources.
...
    Prasad> In theory Alpha/ARC bios is same as MIPS/ARC and since
    Prasad> SysInst is a userland program it should be stable.

    Prasad> Any comments and suggestions is welcomed.

Alpha CPUs use a privileged ROM image called PAL which provides
low-level operating system functions for virtual memory, etc..
Different firmware provides different PALcode:

SRM firmware---with its command line syntax---provides a PAL image
which supports functions required for OpenVMS, Digital Unix, and
NetBSD, like a full 64 bit virtual address space;

ARC firmware (or it's later relative, ArcBIOS)---with it's simple menu
scheme---contains a PAL image which is sufficient to drive Microsoft's
Windows/Alpha, particularly, a constrained 32 bit virtual address
space.

I believe that some Alpha models have both firmware images available,
and can thus boot any of the above OSs.

Linux gets around this ARC PAL limitation by first booting a
`replacement' firmware called MILO which bears an old (and now-
unencumbered), buggy, PAL image.  Unfortunately, this opens a can of
worms in that PALcode is often model-specific, so that each model of
Alpha requires it's own specific version of MILO!

Still, I understand that Ross Harvey has done some investigation into
what is required to get NetBSD booted on top of MILO.  I am told that
he can boot to single-user mode, but any attempt to go multi-user
results in a crash.

I'm interested if you can skirt around this issue with your MIPS/ARC
work, because I have access to an ARC-only Alpha XT 266.

--
Kevin.