Driver question

Elan Feingold elan at
Mon Aug 27 05:53:47 EST 2001


Thanks to all those who helped me get my custom 860 board up and running!
My next question is about mapping some physical memory to user space.  I
have some devices with memory mapped registers.  One of them lives at
0x84000800 (above 2Gb!).  I have been trying to mmap() this into user space
memory, without success (the kernel doesn't like the >2Gb).

>From what I understand, there are usually a few options.  Usually one can
use mmap() -- although I don't know if I can -- or one can write a device
driver to work with kmalloc and friends.

What would be the easiest way to gain access to that physical memory
(non-cached, of course) from user space?  Obviously, it would be nice to map
it in at that very address in user space, but I don't think that's going to
happen.  Any tips would be greatly appreciated, as I'm new to this game.

Best regards,


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