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Address Translation and Attributes

Note: This was originally posted on 24th April 2009 at http://forums.arm.com

I have a memory section mapping as below:

______address_________|_physical_____________|_d_|_size____|_permissions________
____________|_glb|_shr|_access
__C:B0200000--B02FFFFF|__A:01E00000--01EFFFFF|_0F|_00100000|_P:readwrite_U:readwrite________|_yes|_no_|_write-through/buffered

The first level descriptor is at address 00A26C04
___address__|________0________4________8________
SD:00A26C00| >01E00DEA

Hence the physical address for B0200000 is 01E00000.
The Attributes are 0x00DEA.

C = 1
B = 0
XN = 0
domain (d) = 0xF
AP = 0x11
TEX = 0x000
Type = Section (1MB)

TEX (0x000) and CB (0x10) indicate cache policy of Outer and inner write through, no write allocate so my questions are:

1. What determines if it is buffered/non-buffered?
2. Is buffered/non-buffered referring to the use of write buffers?
3. What do inner and outer mean on the system that only have L1 cache?
4. If a memory region is shared between processors and its attributes are non-cache/buffered then do I have to perform data memory barrier operation after writing to any location in that region?

Thanks,
Samar