On Wed, Nov 04, 1998 at 06:09:19PM +0100, Wolfgang Solfrank wrote:
> Hi,
> 
> > Now, let's say you have the newer 7000 model ... On this system the
> > serial port registers are linear (no gap), but the IDE registers are
> > spaced mod 16.  On this system, it's an issue of how the individual
> > chips are wired up, i.e. the stride is per-device.
> > 
> > In the first example, it's appropriate to use stride in the bus space
> > tag.  In the second example, it's appropriate to add register map
> > support in the driver.
> 
> Hmm, that's at least arguable.  To me it looks like the second example is
> an example of bad engineering, and that box should pay the price for it,
> not anyone using the same driver.

One need only look at the ABYSMAL performance of the "le" driver on
architectures where you actually _can_ DMA to/from main memory to see a
pretty glaring example of this.

I'd argue that instead of the VAX using its own LANCE driver, the ports
with a special need for low performance should...

-- 
Thor Lancelot Simon	                                      tls@rek.tjls.com
	"And where do all these highways go, now that we are free?"