ocpbus(4)

[John Baldwin]

On Tuesday 01 January 2008 03:09:50 pm Marcel Moolenaar wrote:
> 
> On Dec 31, 2007, at 1:06 PM, John Baldwin wrote:
> 
> >> Using the hints-way of describing hardware is just not going to
> >> fly in that case, because you're still keying off of device names
> >> and unit numbers. Let that be a consequence of the metadata, not
> >> an integral part of... (device.COM1.* does exactly that).
> >
> > Redo the 'at' hints like this (pci was already this way in the  
> > existing hint
> > wiring stuff anyway, i.e. it's _not_ a new-bus device name in  
> > 'at').  I'll
> > use all-caps to make it stand out:
> 
> While I think that's a good thing, the confusion to the user
> when it comes to the unit number is already present. People
> already assume that if they have hint.sio.0.at="isa" that
> they expect to see device sio0. I fear that it's exactly the
> same with "device.COM1.at=ISA. If the 1 on COM1 is just a
> means to distinguish multiple COM devices, then it's much
> better to use a more structural approach, eliminate the unit
> and instead key-off of something that's truly identifying.

It's a string.  Look at your PC, on the back it has a label with "COM1" 
or "COMA" or some such.  You can call it 'device.IHATECOMPUTERS' if you want.  
The idea is to just give a collection of properties a name so that they can 
all be bound together.

> In other words: hints historically mix the hardware description
> with the assignment of the driver and the unit number. Your
> proposal has the same flaws. The whole thing is just awkward
> for the user and impossible to implement unambiguously.

COM1 is not a new-bus name.  Nowhere in any of the device.FOO is a single 
new-bus name execept for the possible 'driver=foo' property to bind to a 
driver.

That all said, I obviously am unable to come up with anything acceptable to 
your tastes so I'll just give up and work on something else.

-- 
John Baldwin