[Qemu-devel] Re: [OpenBIOS] QEMU OpenBIOS booting?

[Steven Noonan <steven@uplinklabs.net>]

On Sun, Apr 19, 2009 at 1:21 PM, Laurent Vivier <Laurent@vivier.eu> wrote:
> Le dimanche 19 avril 2009 à 13:01 -0700, Steven Noonan a écrit :
>> On Sun, Apr 19, 2009 at 12:47 PM, Laurent Vivier <Laurent@lvivier.info> wrote:
>> > Le dimanche 19 avril 2009 à 11:59 -0700, Steven Noonan a écrit :
>> >> On Sun, Apr 19, 2009 at 1:24 AM, Laurent Vivier <Laurent@lvivier.info> wrote:
>> >> > Le dimanche 19 avril 2009 à 00:50 -0700, Steven Noonan a écrit :
>> >> >> On Tue, Apr 14, 2009 at 10:46 PM, Steven Noonan <steven@uplinklabs.net> wrote:
>> >> >> > On Sun, Apr 12, 2009 at 1:39 AM, Laurent Vivier <Laurent@lvivier.info> wrote:
>> >> >> >> OpenBIOS is not able to boot MacOS X.
>> >> >> >
>> >> >> > Well, that's a silly limitation. Is there a reason this isn't
>> >> >> > implemented? I see that the Mac-on-Linux OpenBIOS version has such
>> >> >> > support, so it seems strange that the QEMU version does not.
>> >> >>
>> >> >> I don't know if anyone here is actually interested (this list seems
>> >> >> -very- quiet), but...
>> >> >
>> >> > Hi,
>> >> >
>> >> >> I've been hacking at OpenBIOS for a bit, and I got it to properly read
>> >> >> Mac OS X discs (it kept failing because it would hit an Apple
>> >> >> Partition Map header instead of an HFS+ filesystem header). I'm
>> >> >> working on adding an XCOFF loader, too, so it should be able to boot
>> >> >> Mac OS X soon.
>> >> >
>> >> > You can copy it from OpenHackWare.
>> >> > I made some tests and it seems to have some memory conflicts between
>> >> > MacOS kernel and OpenBIOS.
>> >
>> > In fact what I have is a Mach-O loader which load mach_kernel from "/".
>> >
>> >> > Good Luck.
>> >> >
>> >>
>> >> Two more pre-XCOFF loader commits up:
>> >> http://github.com/tycho/openbios/commit/e43daa3447b5ce4a2b05b2f32882e49891156200
>> >> http://github.com/tycho/openbios/commit/7023b78a10f5632fd08d4749615efd3e73ab1036
>> >
>> > Seems good but do you really need to check for embedded XCOFF in this
>> > patch and are you really able to execute the boot-script ?
>>
>> Oh, I should say that it does _execute_ the boot-script, but I don't
>> know if it's properly handled by the Forth interpreter. Any idea what
>> the boot-script you cite is supposed to actually _do_ (I gave up
>> trying to read Forth at around 3 AM last night)?
>
> I think the script seeks in itself the address of the embedded XCOFF
> (after "-BOOT"), computes it size, copies it to load-base, initializes
> it ("init-program") and executes it ("go").

Ah, duh, that should've been obvious to me. I'm a Forth flunkie, so if
someone could implement these:

  ( xcoff-base )
  load-size over load-base - -
  ( xcoff-base xcoff-size )
  load-base swap move
  init-program go

Then we'd be doing what we -really- should be doing instead of my
hackish "oh, there's an XCOFF here! let's load it."

>
>> >
>> > In Panther Install CD, BootX is:
>> >
>> > <CHRP-BOOT>
>> > <COMPATIBLE>
>> > MacRISC MacRISC3 MacRISC4
>> > </COMPATIBLE>
>> > <DESCRIPTION>
>> > Boot Loader for Mac OS X.
>> > </DESCRIPTION>
>> > <OS-BADGE-ICONS>
>> > </OS-BADGE-ICONS>
>> > <BOOT-SCRIPT>
>> > ...
>> > <BOOT-SCRIPT>
>> > load-base
>> > begin
>> >  dup 6 " &lt;/CHRP" $= if
>> >  6 + dup 6 " -BOOT&gt;" $= if
>> >   8 + true
>> >  else
>> >   false
>> >  then
>> >  else
>> >  1+ false
>> >  then
>> > until
>> > ( xcoff-base )
>> > load-size over load-base - -
>> > ( xcoff-base xcoff-size )
>> > load-base swap move
>> > init-program go
>> > </BOOT-SCRIPT>
>> > </CHRP-BOOT>
>> > [...XCOFF HERE]
>> >
>> >