On 4/7/11 1:25 PM, Nate Lawson wrote:
On 4/7/2011 6:53 AM, John Baldwin wrote:
On 4/6/11 5:51 PM, Nate Lawson wrote:
Wow, awesome work. This is really useful for fixing a common problem.
Should bus_adjust_resource() be a DEVMETHOD or is this something that
should be done automatically within rman_alloc_resource(), possibly
based on a device flag?
Hmm, I had only thought of it as being a wrapper around
rman_adjust_resource(). I'm not sure what you mean by adjusting it
inside another method? Note that one of the reasons I have the current
method is that different devices may have different restrictions on how
resources can grow. For example, the PCI-PCI memory windows are aligned
on 1MB boundaries and are allocated in 1MB chunks while the I/O port
windows are aligned and allocated in 4K chunks.
I also plan to make use of rman_adjust_resource() for PCI bus
renumbering, but in that case resources would only grow at the end, etc.
Given that, I want to keep the logic to determine which kind of
adjustment to perform in the relevant driver rather than having rman
attempt to use a generic algorithm for expanding a resource and
associated rman used for suballocation (if that makes sense).
Yes, that makes sense. It's a question of complexity -- do you push a
set of rules to rman and have it apply them? Or do you do the adjusting
in the driver itself, which knows its own restrictions but may end up
replicating some general purpose code for applying those restrictions?
This seems great for now. I don't have any complaints, just musing about
the future.
Ahh, ok. So far my current plans for other places using rmans don't
involve the same set of rules. However, I would be happy for their to
eventually be a more general version of pcib_grow_window() if we find a
need for it in the future. I think you could have a helper function at
that level of granularity perhaps.
--
John Baldwin
_______________________________________________
[email protected] mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-acpi
To unsubscribe, send any mail to "[email protected]"
