Re: Using IDMA1 ( or IDMA2 ) on 860

Dan,

quoted

/* version2 of GetChipAddress this WORKS why? */

Because you can't directly access physical bus
addresses from
the kernel.  They have to be mapped to some virtual
address.
The IMMR is mapped to a well known address that can
generally
be used anywhere in the kernel.  Anything else must
be mapped,
as your example shows.  Just make sure you do this
_once_,
don't keep calling ioremap() over and over or you
will exhaust
the VM space and get a different address every time.


	-- Dan

Thanks for all your help and education. One last
question on this, if I have a pointer that is returned
by doing ioremap_noncache() if I want to assign this
pointer in buffer descriptor setup should i be doing
__pa () correct? Will __pa() translate that address
back to the actual physical address?

John


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