Subject: Re: Mobile Pro + NetBSD as a commandline PDA?
To: M. Warner Losh <imp@bsdimp.com>
From: Todd Vierling <tv@duh.org>
List: port-hpcmips
Date: 04/29/2004 19:17:28
On Thu, 29 Apr 2004, M. Warner Losh wrote:

: You are right that it doesn't put things into the lowest CPU mode, but
: that requires new ROMs...

I still have trouble believing this argument.

Has anyone disassembled the ROM starting from the target of the power-on
jump vector to see if it has a "patch hook" that can be intercepted and
routed back to NetBSD?  Typically such a patch hook requires that a certain
magic word be at a specific location in memory, and/or that some sort of
in-memory startup structure be populated.

I've *never* seen an embedded OS in masked ROM without such a hook, to allow
for -- you guessed it -- power management and/or warm reset hardware fixups.
I'm fairly certain that the WinCE "service pack" as distributed by NEC
contains such fixups for machines like ... the MobilePro 800/MC-R700[A].

Unfortunately, my MIPS opcode and architecture knowledge is a little lacking
to do this disassembly interpretation accurately.  sigh.

-- 
-- Todd Vierling <tv@duh.org> <tv@pobox.com>