On Monday 31 October 2005 4:16 pm, Benjamin Herrenschmidt wrote: > On Mon, 2005-10-31 at 16:23 +1100, Paul Mackerras wrote: > > My G4 powerbook gets a machine check on boot as a result of commit > > 478a3bab8c87a9ba4a4ba338314e32bb0c378e62. Putting a return at the > > start of quirk_usb_early_handoff fixes it. > > > > The code in quirk_usb_handoff_ohci looks rather bogus in that it > > doesn't do pci_enable_device before trying to access the device.
No PCI quirk code has ever called pci_enable_device() AFAICT. Of course the _need_ to do such a thing might be another PPC-specific (or OpenFirmware-specific?) PCI thing ... we've hit other cases where PPC breaks things that work on other PCI systems (and vice versa). > That and it doesn't test if the BARs are assigned at all, doesn't > request the resources, etc... If quirk code can't rely on BARs, then the PCI system needs some basic overhauls ... yes? I mean, how could quirk code ever work if it can't access the relevant chip registers?? > I'm not sure it's legal to do pci_enable_device() from within a pci > quirk anyway. I really wonder what that code is doing in the quirks, I > don't think it's the right place, but I may be wrong. Erm, what "code is doing" what, that you mean ?? > What is the logic supposed to be there ? Which logic? The fundamental thing those USB handoff functions do is make sure that BIOS code lets go of the host controllers. The main reason it'd be using a controller is because of USB keyboards, mice, or maybe boot disks. Secondarily, that code needs to make sure the controller is really quiesced before Linux starts using it. - Dave ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today * Register for a JBoss Training Course Free Certification Exam for All Training Attendees Through End of 2005 Visit http://www.jboss.com/services/certification for more information _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
