Linux On A RISC Box?

Noctrnl asks: "I've recently begun a search for a Linux distro to run on my old IBM RS/600 model 250 machines. A lot of PPC projects support the CPU architecture, but I have yet to find one that supports MCA on them. At every turn I can find a distro that supports the PowerPC chip on a PCI-based system, but have been unable to find a distribution that will run on my machines. Are there any projects underway that will allow me to boot a real operating system besides AIX on these babies? Just in case you were wondering, *BSD doesn't support them either."

MCA is the problem

[marcus]

I have not done any extensive research, but as well as I can recall, MCA is not supported by open source software, period. Just about the only thing that came out of the MCA/P2 design that is supported by anyone but IBM and M$oft is the keyboard and mouse connector. ;-P

Complain to IBM about proprietary architectures.

Re:IBM PPC+MCA

[djweis]

Yes, it will be fairly difficult. The docs on the system are nearly non-existant. Also, the MCA bus on these machines is orders of magnitude more complex than on the pc. On a ps/2 you can just poke at a range of 8 io ports to control the bus. On the rs6k's the bus controller shows up on the PPC cpu bus and operates similar to a PCi bus controller on newer machines. You can have up to 4 independant mca busses plus the cpu bus and a video bus.

That said, I'm working on it now :-)

Re:MCA is the problem

[djweis]

glycerine has been shut off for a year or two. it's data has moved to http://dgmicro.com/mca/

Ignorantly answering

[fuerstma]

Well I know that Yellow Dog Linux runs on most PowerPC machines. Actually, there is a writeup in this months Linux Journal about running YDL on some IBM RISC Machines. Maybe it applies?

Re:MCA is the problem

[Tower]

doh! left in some irrelevant files ("I'll just take those out after I finish typing"). Oops. I'm sure you can all figure it out, though.

Re:MCA is the problem

[Tower]

Time to send in a patch for the doc file, I guess 8^D That came out of source d/l just a couple of weeks ago... Sorry I didn't check it first.

Re:MCA is the problem

[Tower]

There has been some bits of MCA support for x86 Linux - I know of a few that have gotten linux running on an old PS/2.

I come up with the following on a quick search...

/usr/src/linux-2.2.14/include/linux/mca.h
/usr/src/linux-2.2.14/include/asm-i386/mca_dma.h
/usr/src/linux-2.2.14/include/config/mca.h
/usr/src/linux-2.2.14/net/core/dev_mcast.c
/usr/src/linux-2.2.14/net/ipv6/mcast.c
/usr/src/linux-2.2.14/drivers/net/smc-mca.c
/usr/src/linux-2.2.14/drivers/net/smc-mca.h
/usr/src/linux-2.2.14/drivers/net/sk_mca.c
/usr/src/linux-2.2.14/drivers/net/sk_mca.h
/usr/src/linux-2.2.14/drivers/scsi/ibmmca.c
/usr/src/linux-2.2.14/drivers/scsi/ibmmca.h
/usr/src/linux-2.2.14/drivers/scsi/mca_53c9x.c
/usr/src/linux-2.2.14/drivers/scsi/mca_53c9x.h
/usr/src/linux-2.2.14/drivers/scsi/README.ibmmca
/usr/src/linux-2.2.14/drivers/isdn/avmb1/avmcard .h
/usr/src/linux-2.2.14/arch/i386/kernel/mca.c
/usr/src/linux-2.2.14/Documentation/mca.txt
/usr/i386-glibc20-linux/include/linux/mca.h

This one is pretty lengthy:
>>> /usr/src/linux-2.2.14/Documentation/mca.txt
and also:
MCA Linux Home Page: http://glycerine.itsmm.uni.edu/mca/

This may be mostly x86 stuff, but hopefully you can find some info to help you along.

The MCA bus was a great thing at the time, but unfortunately is was kept closed and heavily taxed... better than standard ISA though, no doubt about that.

IBM PPC+MCA

[technos]

Nope. Not that bus arch. It wouldn't be terribly difficult, but there aren't too many of the early MCA models out there. Demand for such a 'port' would be exceedingly low. On the upside, MCA on Intel and the RISC arch themselves are supported, so I suppose all it would really take is one moderatly good kernel hacker, two lackeys and a working example.

I wonder how much the company would charge me for a 2xx series? Probably nothing.. Perhaps I've got a project..