Support for 64bit userspace.

[Juli Mallett]

Hi JC,

On Wed, Jul 28, 2010 at 16:32, Jayachandran C. <c.jayachandran at gmail.com> wrote:
> On Wed, Jul 28, 2010 at 2:04 AM, Jayachandran C.
> <c.jayachandran at gmail.com> wrote:
>> Here's my initial work to get 64bit user space.  With this set of
>> changes, I can boot to the single user shell with n64 /sbin/init and
>> /bin/sh.  There are still issues to fix, and the dynamic loader is
>> still not working, but I think this would be a good time to get some
>> initial feedback.
>
> The dynamic loader seems to work after some straight-forward changes.
> The only change is that the got[1] entry needs to be 64-bit.  The
> changes are attached.
>
> There is still an occasional kernel panic in n64, which I need to
> track down - but I think the changes other than pmap.c/pmap64.c are
> ready for check in.  I would like some feedback on pmap64.c I can
> clean it up for check in.

I'm uncomfortable with pmap.c and pmap64.c.  I don't get the
impression that the ifdefs required to do both in the same file are
really a great burden, but obviously my efforts are incomplete
compared to yours.  It seems like there are very few operations that
should care about how deep the page tables are and that macros and
ifdefed inline functions are the way to go.  If you check it in as two
files, I'll probably just go through and ifdef the deltas that can't
be eliminated.  What do you think are the problem areas that justify
having two different files?

Thanks,
Juli.