Re: NetBSD on a PowerBook G4

[David Young <dyoung%pobox.com@localhost>]

On Tue, Aug 26, 2008 at 07:30:44PM -0400, Taylor R Campbell wrote:
>    Date: Thu, 5 Jun 2008 19:37:23 -0400
>    From: Michael Lorenz <macallan%netbsd.org@localhost>
> 
>    We need:
>    - - power management support in relevant PCI host bridge drivers  
>    ( uninorth and ohare, maybe heathrow as well )
>    - - many macppc-specific device drivers lack all power management  
>    support. On the other hand, at least ADB is handled by the PMU anyway  
>    and in newer PowerBooks there isn't that much proprietary hardware left
>    - - code to tell the PMU to fall asleep ( should be easy )
>    - - code to deal with uninorth's power control registers ( there are  
>    two 32bit registers which control things like power to various  
>    devices, PCI, firewire etc. clock and so on )
>    - - code to re-initialize the graphics chip on wakeup. This may work  
>    with radeonfb but radeonfb has trouble on some chip variants.
> 
>    Many machine-independent PCI device drivers already have power  
>    management support. It works pretty well on quite a few x86 laptops.
> 
> I have been paying too little attention for the past couple of months
> since this email, but I'm still interested in these.  However, I know
> next to nothing about most of these subjects.  Would you care to
> elaborate upon where one might start if one were to work on these
> things, now that I've finally gotten around to eliminating the other
> showstopper (wifi?

Taylor,

Let me suggest one way to proceed.  Use drvctl -S/-R to try to
suspend/resume device sub-trees.  You will find that some drivers will
not suspend/resume because they do not register pmf(9) handlers, or else
because the handlers are broken.  Fix those drivers.  Work on drivers
that are MI, first, and then the MD drivers.  Keep on testing/fixing
drivers until you can put most devices to sleep and wake them without a
freeze or crash.  When every driver can suspend/resume its device, move
onto the macppc-specific issues that Michael suggested: program the PMU,
fiddle with UniNorth power registers, et cetera.

Dave

-- 
David Young             OJC Technologies
dyoung%ojctech.com@localhost      Urbana, IL * (217) 278-3933 ext 24