Accessing BCSR's

Jeremy Rosen Jeremy.Rosen at
Mon Mar 4 10:32:40 EST 2002

Hello everybody,

I have 860T FADS board, and I am trying to access the (board specific)
registers BCSRs.

I have no problem accessing them in PPCBOOT, since they are accessed
through CS1, at address FF01xxxx, but I can't access them in linux for
the moment.
My first attempt was by using the /dev/mem device, but it doesn't seem
to work, the result read are not correct.
so I have to question
1) why doesn't it work, I probably don't understand how /dev/mem works
: does it map only memory and not the address space ? do I have to
register the address range or the BCSR in the kernel ?
2) what is the proper way of doing this ? writing a driver ? or using
/dev/mem properly ?

thx for your help...


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