Re: CP0 EntryLo

[Pete Popov <ppopov@embeddedalley.com>]

Maciej W. Rozycki wrote:
> On Tue, 30 Nov 2004, Gilad Rom wrote:
>
>
> > So, what I need to do, if I understand correctly, is to create a fixed
> > mapping
> > > From a virtual address to a physical address on the tlb, and use this
> > Virtual address to change the values of EntryLo to 0xD in order to 
> > Access the device on the address range I mapped Chip-select 1 to?
> > (Excuse my poor phrasing, I've been googling all day...)
> >
> > Any idea on how I might accomplish that from a driver?
> > I've found a function called add_wired_entry(...), is this
> > What I should be using?
>
>  ioremap()
Exactly. You program the CS with a physical address. Make sure that 
address does not overlap with anything else. Then you call ioremap 
from your driver and you get back a virtual address. You use that 
virtual address to access the peripheral.
At this stage I would say that probably reading something like the 
Linux Kernel book or Linux Device Drivers both by Oreilly will 
really help you.
Pete