PERFORCE change 43464 for review
Nate Lawson
nate at root.org
Tue Dec 9 22:32:48 PST 2003
On Tue, 9 Dec 2003, Nate Lawson wrote:
> On Tue, 9 Dec 2003, M. Warner Losh wrote:
> > John Baldwin <jhb at FreeBSD.org> writes:
> > : On 09-Dec-2003 M. Warner Losh wrote:
> > : > John Baldwin <jhb at freebsd.org> writes:
> > : >: On 05-Dec-2003 Nate Lawson wrote:
> > : >: > On Fri, 5 Dec 2003, John Baldwin wrote:
> > : >: >> Change 43464 by jhb at jhb_blue on 2003/12/05 12:59:01
> > : >: >>
> > : >: >> More updates. Closer to working than I thought. In theory
> > : >: >> PCI devices should all just work now.
> > : >: >
> > : >: > This handles PCI. Are you ok with me adding the call to
> > : >: > acpi_pwr_switch_consumer() for non-PCI devices like the embedded
> > : >: > controller? I think we need to do this at the top \\_SB level. I'm a bit
> > : >: > confused as to the handoff between the general tree walk and the ACPI-PCI
> > : >: > driver though.
> > : >:
> > : >: It won't hurt to switch a device on twice. It should be ok to
> > : >: do a top-level tree walk of all device objects and turn them on
> > : >: before probing child devices I think. ACPI shouldn't turn off
> > : >: devices that don't probe like PCI does though because ACPI has
> > : >: duplicate objects of things like the entire PCI device tree. :-/
> > : >
> > : > Actually, there can be times when you don't want to turn on devices at
> > : > all. Walking the whole tree turning them on might be the wrong to
> > : > do...
> > : >
> > : > Sometimes I think that things in the newbus tree should have a pointer
> > : > to the acpi power methods that are used in coordination with the bus
> > : > code that is 'activating' the device before the 'probe' and 'attach'
> > : > happens.
> > :
> > : I think having a 'bus_set_power_state()' method in the bus layer
> > : and having device_probe_and_attach() do 'bus_set_power_state(child, ON)'
> > : would be sufficient. ACPI busses would then perform the correct hooks
> > : via their bus_set_power_state() methods.
> >
> > That is very close to what I had in mind. My only 'debate' was 0/1 or
> > 0,1,2,3 or ????
Oh, and I like the idea of using 0-3 and having them #defined. This is
common to PCI and ACPI D-states.
-Nate
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