Subject: Re: 64-bit memory fun with an adaptec 3950U2B..
To: Bill Studenmund <wrstuden@nas.nasa.gov>
From: Chris G. Demetriou <cgd@netbsd.org>
List: tech-kern
Date: 03/13/2000 18:30:08
further comment (since i confused jason 8-):

cgd@netbsd.org (Chris G. Demetriou) writes:
> at the very minimum, you'll need to:
> 
> 	* make sure bus_addr_t is 64-bits wide, and you might want
> 	  bus_size_t to be as well.

to be clear, this is only if the bios/firmware/whatever actually maps
things such that you need more than the low 32 bits.

if it always puts things in the low 32 bits, or if you're just brave,
you can still keep using 32-bit bus_addr_t/bus_size_t, and:

> do the basep/sizep assignments, and if you do them and if *basep !=
> tmp_address print a warning and fail, or if *sizep != tmp_size print a
> warning and fail.

this should transparently handle the case where your bus_addr_t and
bus_size_t aren't wide enough to hold the resulting sizes.



cgd
-- 
Chris Demetriou - cgd@netbsd.org - http://www.netbsd.org/People/Pages/cgd.html
Disclaimer: Not speaking for NetBSD, just expressing my own opinion.