mmap : please help !

Fillod Stephane stephane.fillod at
Thu Apr 14 02:33:59 EST 2005

Sophie CARAYOL wrote:
> What is the good manner to read or write in the physical memory?

Please have a look at Denx's FAQ for accessing memory bus:
or shorter:

Depending on the O_SYNC flag passed to open, the mmap'ed memory will be
accessed through non guarded cache or not. See linux/drivers/char/mem.c.
The ppc instruction "eieio" deals with I/O ordering.


PS: be careful not sending twice the same mail to the list 

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