From owner-freebsd-hardware Wed Jul 9 19:06:26 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id TAA29267 for hardware-outgoing; Wed, 9 Jul 1997 19:06:26 -0700 (PDT) Received: from silvia.HIP.Berkeley.EDU (ala-ca13-05.ix.netcom.com [204.32.168.37]) by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id TAA29262; Wed, 9 Jul 1997 19:06:16 -0700 (PDT) Received: (from asami@localhost) by silvia.HIP.Berkeley.EDU (8.8.6/8.6.9) id TAA16248; Wed, 9 Jul 1997 19:06:11 -0700 (PDT) Date: Wed, 9 Jul 1997 19:06:11 -0700 (PDT) Message-Id: <199707100206.TAA16248@silvia.HIP.Berkeley.EDU> To: se@FreeBSD.ORG CC: bugtraq@polynet.lviv.ua, freebsd-hardware@FreeBSD.ORG In-reply-to: <19970709195829.49457@mi.uni-koeln.de> (message from Stefan Esser on Wed, 9 Jul 1997 19:58:29 +0200) Subject: Re: Q:PCI bridges-extenders supported From: asami@cs.berkeley.edu (Satoshi Asami) Sender: owner-hardware@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk * In case this is not sufficient, there are some PCI * extender boxes, but I never used one myself. ASAMI * Satoshi has some experience with them. I'm the ASAMI Satoshi Stefan is talking about. We got our PCI expansion boxes from Bit3 (www.bit3.com). We haven't done much more than a little testing, but they appeared to work ok. The model we have has 7 slots in the expansion box; subtracting the 1 slot taken from the main bus for the connector card, each box adds 6 slots net behind three levels of PCI-PCI bridges. In the picture above, "=" are the PCI slots. One of the slots in the expansion box is designated for the connector card (marked with "*"). The bridge chips are marked with "B". (Note the connector cable between the main unit and the expansion box is also a separate PCI bus.) Motherboard | expansion box bus 0 | bus 1 bus 2 -=-=-=-=- -*-=-=-=-B-=-=-=-=- | | B---B bus 1 Our units have the IBM PCI-PCI bridge chips. The DEC bridge chips (they are used in Adaptec 3940) work fine too. * You should expect FreeBSD to work with all bug-free * PCI chip sets. All current Intel chip sets work just * fine, and I think SiS is generally OK, too. There * have been problems with Compaq and ALI chip sets, * but workarounds are implemented to compensate for * their bugs ... Note that it also depends on the BIOS if you want to use deep bridging like the above. At the time we tested (1 1/2 years ago), at least Award BIOS didn't support more than one level of bridges (so we could use 3940's but not the expansion boxes). This may have changed. * Let me know, if you have any problems with some chip * set and I'll send debug patches and will try to find * a fix as soon as possible. Yeah, he's very good at that. I can vouch for him. :) Satoshi