Re: Risc 6000 Power3-II support

[Matt Thomas <matt%3am-software.com@localhost>]

At 02:55 PM 4/8/2003, David Edelsohn wrote:
> >>>>> Jochen Kunz writes:
>
> Jochen> Aha, interresting. Do we have 64 bit PowerPC support beside 
> running a 64
> Jochen> bit PowerPC CPU in 32 bit compatibility mode? (If there is such a 
> mode?)
>
>         64-bit PowerPC can run in 32-bit mode or 64-bit mode for the OS
> and 64-bit mode or 32-bit mode for the applications.  A 32-bit OS can run
> 64-bit applications and vice-versa.  One needs a minimal amount of 64-bit
> assembly code to manipulate the 64-bit memory management and machine
> status registers, but one otherwise can run a 32-bit OS.  In other words,
> the OS must be 64-bit aware, but need not run in 64-bit mode.

I've done quite a bit of work making the powerpc code 64bit clean including
the pmap (the only thing I have left to do there is the segment table).
Most of the work remains in the assembly code; mostly using macros for things
like lwz/stw when those are manipulating pointers (lwz -> lptr, stw -> stptr)
so that ld,std (64bit load/store) can be easily substituted.

Note that the above includes gcc changes as well to have a netbsd64 mode.

I have a Power III machine (43P model 260) but haven't been successful in
getting it to stop in OFW.  I'd love a 970 eval board to play with... :)



--
Matt Thomas               Internet:   matt%3am-software.com@localhost
3am Software Foundry      WWW URL:    http://www.3am-software.com/bio/matt/
Cupertino, CA             Disclaimer: I avow all knowledge of this message