Noah Yan wrote:
> What the advantage to use Genesi Pegasos II comparing using Apple PowerMac?
> What would be the major difference to port Solaris in these two type
> machines, as far as we tell currently? I bought an old PowerMac G4
> GigbitEthernet, a dual-7400 machine from ebay(the only one that I can afford
> for this work). It runs pretty good, I have no problem to compile GRUB2 and
> configure it to load and boot the linux kernel.
>
> Do we port from Solaris x86? but it seems that sparc is more similar to
> PowerPC than x86, am I right?
>
> Also, netbsd-macppc is a very good reference for the porting.
The most important thing is that every piece of the Pegasos II is fully
documented.
Apple does not document their hardware for developers outside of Apple, so
while documentation can be found for off-the-shelf components used in PowerMacs,
details of how Apple's various custom ASICs and I/O controllers are not. The
only details we have about them are what can be determined by reading the Darwin
kernel source code (and by reading the Linux source code.) We also have no way
of knowing how correct either of those code bases are in their dealings with
the hardware and certainly don't know what things the hardware may be CAPABLE
of
doing that the software does not currently support.
As far as the starting point, much of the Solaris source code is common to both
SPARC and x86. Where hardware-specific issues come up, it would make more sense
to base the VM code on the x86 code due to the fact both PPC and x86 use similar
VM mechanisms (page tables whose entries are automatically inserted into the TLB
on a miss). Likewise, it would make more sense to base the boot process on
SPARC's boot process, given both SPARC and PPCs boot using OpenFirmware, though
there is something to be said for making GRUB2 the booter for PPC.
Finally, BSD can be a good reference for various porting issues, though of
course many of the concepts in BSD do not map cleanly to Solaris (and
vice-versa.)
William Kucharski
william.kucharski at sun.com
