clean way to support >32bit addr on 32bit CPU

Dave
2005-01-10T23:50:24Z

I have this ARM (XScale) based platform that supports 36bit physical
addressing. Due to the way the ATU is designed, the outbound memory
translation window is fixed outside the first 4GB of memory space, and
thus the need to use 64bit addressing in order to access the PCI bus.
After all said and done, the struct resource members start and end
must support 64bit integer values in order to work. On a 64bit arch
that would be fine since unsigned long is 64bit. However on a 32bit
arch one must use unsigned long long to get 64bit. However, if we do
that then it would make the 64bit archs to have 128bit start and end
and probably wouldn't be something we'd want. What would be a nice
clean way to support this that's acceptable to Linux? I guess this
issue would be similar to x86-32 PAE would have?

Also, please cc me on on the discussion. Not sure if my LKML
subscription is working... Thanks!

--
-= Dave =-

Software Engineer - Advanced Development Engineering Team
Storage Component Division - Intel Corp.
mailto://dave.jiang @ intel dot com
http://sourceforge.net/projects/xscaleiop/
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