Re: macppc vs evbppc binary packages

[Eduardo Horvath <eeh%NetBSD.org@localhost>]

On Wed, 18 Apr 2012, Greg Troxel wrote:

> We are trying to build packages on some evbppc systems (under
> -6/current) and finding them a bit crashy under load.  So I am wondering
> to what extent packages built on a macppc (that's from 2001 or so,
> dual-core 500 Mhz G3) will run on an evbppc.   I would expect all the
> instructions in the G3 to be present in the new chips (although I
> understand the memory management architecture is different).   But, I
> wonder if the ABI is somehow different.  I'd appreciate advice voting
> for:
> 
>   yes, it ought to work
> 
>   maybe - worth trying
> 
>   you're doomed, don't bother

PowerPC exposes the cache layout to userland to userland for things like 
memcpy.  Originally the cache layout was hardcoded in libc.  When working 
on the IBM 4xx port we added code to libc to read the cache layout 
information.  That was arount 2000-2001.  So if you're running an old 
macppc userland on a chip that has a slightly different cache layout you 
may have some issues.

Then there's also the FPU emulation code that I did for the 4xx port which 
is needed to run things like newfs and fsck.

Eduardo