Subject: Re: bus_space_subregion question
To: None <>
From: Ignatios Souvatzis <>
List: tech-kern
Date: 04/26/2000 16:12:35
On Wed, Apr 26, 2000 at 03:02:32PM +0100, Ben Harris wrote:
> What are the units of "offset" parameter to bus_space_subregion?  The
> arm32 "mainbus" (and the current arm26) space seems to make it the units
> of the underlying CPU address space, which means that the offsets make
> sense to someone looking at addresses in the manual, while the arm32
> "podulebus" space makes it the same units as the "offset" parameter to the
> bus_space_read_* and bus_space_write_* functions.
> Thinking about it, I think the latter way is right, since otherwise MI
> drivers can't sensibly use bus_space_subregion.  Anyone disagree?

No, you're right.

For the Amiga, where each zbus board needs a different interleave factor
(or worse), I resorted to make each zbus board (that is bus-spaced) its own
bus-space bus.

This is also needed for a lot of mainbus chips.


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