Hi,
In the file Documentation/IO-mapping.txt it has been written as follows
"----------
Now, just as an example, on the PReP (PowerPC Reference Platform), the
CPU sees a memory map something like this (this is from memory):
0-2 GB "real memory"
2 GB-3 GB "system IO" (inb/out and similar accesses on x86)
3 GB-4 GB "IO memory" (shared memory over the IO bus)
Now, that looks simple enough. However, when you look at the same thing from
the viewpoint of the devices, you have the reverse, and the physical memory
address 0 actually shows up as address 2 GB for any IO master.
-----"
Would someone please clarify how does an IO master sees physical memory address 0 as 2GB?. Is it specific to PowerPC?
Thanks in advance,
Sudheer
