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SubjectRe: Memory Started not at 0x00000000
Date
NIIBE Yutaka writes:
> That's PAGE_OFFSET + (pysical)MEMORY_START_ADDRESS, where PAGE_OFFSET
> == 0x80000000. THe physical address will generated by masking the
> virtual address with 0x80000000, with no TLB lookup.

I'm not 100% clear what the above is trying to say, however, from what I
know, what's in the code, and what has been discussed earlier (I'll have
to look out the thread, I think with Kanoj, Ingo, or Andrea), PAGE_OFFSET
is *NOT* the offset from physical RAM to the kernels virtual view of RAM.

PAGE_OFFSET is the offset of the kernel virtual view of RAM from virtual
address 0.

If anyone wants more, I'll dig out the thread and the proof. However, IMHO,
this macro is very very badly named.
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| | Russell King rmk@arm.linux.org.uk --- ---
| | | | http://www.arm.linux.org.uk/~rmk/aboutme.html / / |
| +-+-+ --- -+-
/ | THE developer of ARM Linux |+| /|\
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