linux/arch/xtensa/mm
Johannes Weiner c947a585ab xtensa: cope with ram beginning at higher addresses
The current assumption of the memory code is that the first RAM PFN in
the system is 0.

Adjust the relevant code to play well with setups where memory starts
at higher addresses, indicated by PLATFORM_DEFAULT_MEM_START.

The new memory model looks like this:

+----------+--+----------------------+----------------+
|          |  |                      |                |
|          |  |         RAM          |                |
|          |  |                      |                |
+----------+--+----------------------+----------------+
|          |  |                      |                |
+- PFN 0   |  +- min_low_pfn         +- max_low_pfn   +- max_pfn
           |
           +- ARCH_PFN_OFFSET
           +- PLATFORM_DEFAULT_MEM_START >> PAGE_SIZE

The memory map contains pages starting from pfn ARCH_PFN_OFFSET up to
max_low_pfn.  The only zone used right now will span exactly the same
region.

Usually, ARCH_PFN_OFFSET and min_low_pfn are the same value.  Handle
them separately for robustness.  Gapping pages will be in the memory
map but marked as reserved and won't be touched.

Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2009-04-02 23:41:08 -07:00
..
cache.c [XTENSA] Flush the page-address in update-mmu instead of user-address 2008-02-13 16:58:51 -08:00
fault.c xtensa: fix compilation somewhat 2009-03-10 15:55:10 -07:00
init.c xtensa: cope with ram beginning at higher addresses 2009-04-02 23:41:08 -07:00
Makefile Remove references to "make dep" 2008-01-28 23:22:13 +01:00
misc.S [XTENSA] Fix icache flush for cache aliasing 2008-02-13 17:08:18 -08:00
pgtable.c fix file specification in comments 2006-10-03 23:01:26 +02:00
tlb.c [PATCH] xtensa: remove extra header files 2006-12-10 09:55:39 -08:00