Can't access memory region
adam at os.inf.tu-dresden.de
Thu Feb 3 21:38:27 CET 2011
On Thu Feb 03, 2011 at 20:03:46 +0000, Jason Philip wrote:
> > Does it work if you request only one port at a time?
> I think it does what happen I request a I/O Fpage start at 0x300 (which don't
> work) then later in the code I request a I/O Fpage start at 0x000A0000 and it
> works. So I assume it will work for one Fpage at a time.
Ah, when seeing the 0x300 I was thinking of I/O ports, not of I/O
memory, which are different things. For memory (whether I/O or not) you
have to use page-size granularity, i.e. multiples of 0x1000. However for
ports, 1-port granularity should work. Getting 0x100 ports from
0x300-0x400 meets the alignment constraints so it should work.
Adam adam at os.inf.tu-dresden.de
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