[parisc-linux] Re: NCR53c720

James Bottomley James.Bottomley@steeleye.com
30 Sep 2003 10:32:23 -0500

On Tue, 2003-09-30 at 08:59, Matthew Wilcox wrote:
> It makes a lot of sense to treat all the devices that firmware tells us
> about as parisc_devices since we treat them all the same way.  If we
> were stepping over ourselves saying "well, yes, this is a pluggable
> device and therefore we have to access it like that, but this one's
> on the motherboard and therefore we treat it like that", I'd agree.
> But all these devices are in the same namespace, firmware tells us
> about all of them in the same way, so I think we should continue with
> the parisc_device.

Yes, I was just musing about the way we did it.  In theory, the
difference between a "platform" device and a generic device is that a
generic device has a bus, and a platform one doesn't.  The
platform_device also has a resource pointer and a few other bits and
pieces the generic device doesn't.

What I did for PA was to create a parisc bus type, and attach all the
inventoried hardware to it.  This blurs the bus distinction in generic
device because we have several inventoried buses: Runway, GSC, LASI etc.
that are all lumped under the parisc bus.

I was just wondering if it wouldn't make more sense now for us to be
using platform devices too...


> >From a historical perspective, we've had parisc_devices in
> one form or another since the very start of the project.
> They were called hp_devices until about August 2001.  See
> http://ftp.parisc-linux.org/patches/parisc_device-2.diff for the
> conversion.
> I don't know much about Amiga/Zorro.  Maybe it'd make sense for Amiga
> platform devices to be faked as zorro_devices, but I doubt it.  In
> any case, the 4000T SCSI is a 53c710, not a 720.
> -- 
> "It's not Hollywood.  War is real, war is primarily not about defeat or
> victory, it is about death.  I've seen thousands and thousands of dead bodies.
> Do you think I want to have an academic debate on this subject?" -- Robert Fisk