Date: Thu, 18 Jul 2002 10:46:24 -0400 (EDT) From: "Wesley Morgan" <morganw@chemikals.org> To: <current@freebsd.org> Subject: Re: When will PCI_ENABLE_IO_MODES be default? Message-ID: <33450.148.175.49.1.1027003584.squirrel@www.chemikals.org>
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So, how much does this have to do with my laptop's sound (DSP) dumping out after about 10 seconds? (Toshiba had the great idea of hard-wiring most everything through IRQ 11, although pccardd seems to be able to use others) > Longer Answer: For some time now MS has had the notion of a Plug and > Play OS at the BIOS level. Most BIOSes had the ability to say "This OS > is a Plug and Play OS" and would refrain from assigning resources to > the pci cards that might be a pita for the PnP OS to deal with down the > road. In a Plug and Play OS, it deals with resource issues > compeletely and totally (except for devices required to boot the > system, iirc). In a non PnP OS, like FreeBSD, the OS expects the BIOS > to have assigned all the resources and activated all the cards. > > For years, this worked great. ACPI can be viewed as an even more > extensive attempt to get the OS to assign all the resources to the > cards. Now with ACPI in more and more BIOSes, they are shipping w/o > the ability to turn off PnP OS. They assume that the OS will be at > least PnP, if not fully use the ACPI paradigm[*] to do its resource > thing. FreeBSD has to cope with this better in general. > PCI_ENABLE_IO_MODES is a kludge that only kinda makes things better. > > NetBSD does a better job at this by enumerating things at boot time and > assigning resources when the big picture is being looked at. > FreeBSD should do this as well. We will have to deal with assigning > things that could need more resources later, like cardbus and cPCI > bridges, "big" chunks of space that they can later dole out as > needed. pci bridges make this problem more interesting because some of > them will only decode certain address ranges (which is the cause of > another kludge in the pci code). > > You can do a web search for the pc99 design guide (and newer ones). > They go into some of this. The ACPI standards docs also go into this > as well, although the 1.0 verion didn't do it very well (imho). There > are a number of other places to look for information too. The > mindshare books might be good. > > I'm not aware of one place the ties all of these "customs" together > into a coherent hole :-(. > > > Warner > > [*] These are wesil words for "The OS does all the resource > assignment." To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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