Date: Thu, 05 Oct 1995 17:53:49 -0700 From: "Justin T. Gibbs" <gibbs@freefall.FreeBSD.org> To: Jake Hamby <jehamby@lightside.com> Cc: Dave Hayes <dave@elxr.jpl.nasa.gov>, freebsd-hardware@freebsd.org Subject: Re: New PCI cards and FreeBSD Message-ID: <199510060053.RAA18216@aslan.cdrom.com> In-Reply-To: Your message of "Thu, 05 Oct 1995 17:32:45 PDT." <Pine.AUX.3.91.951005172552.22726A-100000@covina.lightside.com>
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>On Thu, 5 Oct 1995, Dave Hayes wrote: > >It is. I'm sorry, I thought you were trying to build a custom kernel >(that's what my chapter was about, and I'm afraid it's a little on my >brain). You can change port and IRQ from "boot -c" but if the device >isn't recognized at all, there's not much you can do. Try the "probe" >command with "ix0" and "ahc0" and see if it picks them up as >ISA-emulation devices. The ahc driver is a full blown pci driver. There is no "isa emulation" about it. It does support eisa/vl versions of the card as well, but handles them through probe and attach routines specific to those buses. >The PCI->ISA bridge allows devices on the PCI bus to look like ISA >devices. For example, an old DOS program doesn't need to know you have a >PCI video card, it accesses it just like any other. Similarly, most PCI >cards I've seen, will act like a similar ISA card, except with a 32-bit >datapath. That's why I was hoping your cards would be recognized by the >kernel as ISA cards. The PCI->ISA bride is used to attach an ISA bus onto the PCI bus. This is how most ISA slots are provided on today's motherboards. It has nothing to do with PCI devices that have an ISA compatibility mode. PCI video cards, for example, show up just like any other kind of video card because their VGA registers are mapped by default to the standard VGA I/O location. >> Dave Hayes -- Institutional NETworks - Section 394 -- JPL/NASA - Pasadena CA >> dave@elxr.jpl.nasa.gov dave@jato.jpl.nasa.gov ...usc!elroy!dxh -- Justin T. Gibbs =========================================== Software Developer - Walnut Creek CDROM FreeBSD: Turning PCs into workstations ===========================================
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