Re: Feature Request: Alpha-Linux support.. possible?

[Stefan Reinauer <stepan@coresystems.de>]

* Brian Evans <grknight2k@bluebottle.com> [070615 18:38]:
> The current DEC Alpha boot loaders MILO and aboot are unmaintained and
> frequently break with newer tool chains and kernels.

I have a machine for aboot, but I don't have a machine for MILO anymore.

MILO is still up and running on http://milo.coresystems.de/ but I had no
requests for changes in several years now.

> How hard would it be to add Alpha to Grub-2?

It'd probably be a lot easier to add support for SRM based systems than
for AlphaBIOS/ARCS based systems since those are using a 32bit PAL code,
effectively making the machine a 32bit machine on the BIOS level. The
workaround is to load 64bit PAL codes, such as those found in SRM or
MILO. The draw back is that you can not use BIOS callbacks anymore after
switching the PAL code so you have to provide your own SCSI drivers for
each controller. Hence MILO was married with the Linux kernel in a more
than unnatural way.

One possible scenario however:

1. Get the latest SRM PAL codes for all machines supported by MILO
   (MILOs PAL codes suck!)

2. Strip down MILO so it does not link against the kernel at all
   anymore. I know Nikita worked on that a long time ago and I 
   removed that stuff. I had to learn the hard way that this was a
   mistake

3. Patch Linload.exe/Loadlin.exe to load MILO plus a Kernel plus an
   initrd from the DOS partition. Jay, do you have the sources for the
   Ruffian loader? Is it still closed up? Could we change it and
   recompile it?

4. Have MILO start the Linux kernel from RAM loaded by 3.

5. Use kexec and whatever neat userspace utility to load the real Kernel
   from disk. Or just write the real kernel to the DOS partition and
   load it from there with no kexec in the game.

The big problem that kept me from trying that is that you need the
AlphaBIOS SDK (?) installed on a Windows box to patch
loadlin.exe/linload.exe and you need an (Alpha?) Windows box for that
which I did not have at the time.

> However, I do have an Alpha box to test with (read: break).
 
SRM? Alpha BIOS?

> Although the Alpha platform is no longer producing any new machines,
> many exist as servers or workstations and could be reused as Linux machines.

I want to revive mine, too, but I think I gave my Permedia2 card away by
accident and I dont have a supported card at the moment that would also
work in VMS :-( Guess Ebay is my friend.

Stefan


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