Date: Sun, 08 Jul 2001 00:21:33 -0600 From: Warner Losh <imp@harmony.village.org> To: Mike Smith <msmith@FreeBSD.ORG> Cc: Makoto MATSUSHITA <matusita@jp.FreeBSD.org>, sos@freebsd.dk, current@FreeBSD.ORG Subject: Re: Problems with ata probing twice. Message-ID: <200107080621.f686LXJ76403@harmony.village.org> In-Reply-To: Your message of "Sat, 07 Jul 2001 14:41:13 PDT." <200107072141.f67LfD702155@mass.dis.org> References: <200107072141.f67LfD702155@mass.dis.org>
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In message <200107072141.f67LfD702155@mass.dis.org> Mike Smith writes: : > Actually, there is a reason. Ata is special like pcic is special. : > Both of them can have multiple interrupt routing methods. When ata is : > connected directly to the south bridge, it can route ISA interrupts, : > even though it is a pci device. In this case, it is unsafe to share : > interrupts between the ata device and anything else. Even though it : > looks like a pci device, the interrupt routing is ISA. : : This just reinforces what I said; shareability has nothing to do with the : driver, and everything to do with where the interrupts come *from*. Right. : > Cardbus bridges in laptops have the same problems. And it is looking : > like we can't just use the pcibios to route the interrupts on some : > older machines so we have to have some way to say "use isa interrupts : > for this device." That's a big pain for cardbus bridges because many : > of them would really like to be pci devices so you can relocate memory : > out of the ISA hole, etc. : : There's no reason they can't be PCI devices, but using interrupts from : ISA. No reason except that the current pci code always will try to route pci interrupts and never acts as a simple pass through. Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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