Subject: O2 ARCS

From: "Soren S. Jorvang" <[email-masked]>
Date: Wed, 17 May 2000 05:15:24 +0200

Hi,

I seem to remember some dire warnings about the O2 ARCS PROM
needing special care and feeding to even do basic stuff. Am I
on crack?

FWIW, as a system console it works just for me as the Indy, at
least well enough to do PCI enumeration and play with NetBSD DDB.

Of course, there still isn't really any hardware documentation
beyond sys/mace.h and friends..

-- 
Soren

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From: Ralf Baechle <[email-masked]>
Date: Wed, 17 May 2000 21:53:11 +0200

> beyond sys/mace.h and friends..

The ARCS firmware isn't the big deal but the R10000 support for this
system or any other non-cachecoherent system.  Harald Koerfgen has
started poking at an O2 port and he's got first success.

  Ralf

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From: Florian Lohoff <[email-masked]>
Date: Thu, 18 May 2000 01:16:56 +0200

> started poking at an O2 port and he's got first success.

BTW: Is there any Documentation for the ARC Firmware of the SGIs ?

Flo
-- 
Florian Lohoff		[email-masked]		      	+49-subject-2-change
"Technology is a constant battle between manufacturers producing bigger and
more idiot-proof systems and nature producing bigger and better idiots."

---

From: Ralf Baechle <[email-masked]>
Date: Thu, 18 May 2000 13:47:35 +0200

> BTW: Is there any Documentation for the ARC Firmware of the SGIs ?

I've got various dead tree document which document ARC.
First there is the ARC standard, a document which is Microsoft and ACE
copyrighted.  This also defines various hardware properties like plugs,
screen resolution, audio etc.  These were already fairly lowend by '94
when I first saw the document.  Consequentially a new standard was
named ``Microsoft Portable Bootloader Standard'' was created which
essentially is just most of the software parts from the full ARC
standard.  Both documents are completly NT centric.  In the meantime I
somewhere saw a newer version of the ARC standard which afair is
copyrighted by some publishing company (Addison Wesley?).  Not sure if
it was actually published as a book.  Finally there is SGI's variant
ARCS which is big endian and has various other minor changes from the
Portable Bootloader Standard.  I don't know of any documentation.

Not all SGI machines do even use ARCS.  The older ones have a MIPS-style
firmware, more current ones like the Origin have a ``enhanced subset''
of ARCS.  Look into include/asm-mips64/sn/kl{config,dir}.h to find
how those datastructures look.  On the Origin for example quering the
ARCS configuration tree doesn't work at all.  For this new style
configuration information there is not much more documentatin available
than these IRIX header files.

  Ralf

---

From: "Soren S. Jorvang" <[email-masked]>
Date: Thu, 18 May 2000 15:16:57 +0200

> BTW: Is there any Documentation for the ARC Firmware of the SGIs ?

While not quite identical to the SGI ARCS firmware, 
http://www.microsoft.com/hwdev/download/respec/riscspec.zip
is useful.

-- 
Soren

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From: Ralf Baechle <[email-masked]>
Date: Thu, 18 May 2000 17:28:09 +0200

> http://www.microsoft.com/hwdev/download/respec/riscspec.zip

Staring at the winword file in this archive with strings this pretty much
looks like one of the dead tree copies I was using for my work, so it's
definately usable.  The ARC / ARCS differences are not too big, just look
into arch/mips/arc/ which handles them.  The differences between specs and
real world implementation is another thing - I haven't yet seen a single
implementation that conforms to the spec.  Which is why I believe the
ARC spec should best be locked up in Fort Knox ;-)

  Ralf