From owner-freebsd-hackers Fri Nov 8 15:21:31 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id PAA17774 for hackers-outgoing; Fri, 8 Nov 1996 15:21:31 -0800 (PST) Received: from clem.systemsix.com (clem.systemsix.com [198.99.86.131]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id PAA17762 for ; Fri, 8 Nov 1996 15:21:28 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by clem.systemsix.com (8.6.12/8.6.12) with SMTP id QAA02908; Fri, 8 Nov 1996 16:21:10 -0700 Message-Id: <199611082321.QAA02908@clem.systemsix.com> X-Authentication-Warning: clem.systemsix.com: Host localhost didn't use HELO protocol X-Mailer: exmh version 1.6.5 12/11/95 From: Steve Passe To: se@zpr.uni-koeln.de (Stefan Esser) cc: freebsd-hackers@freebsd.org (FreeBSD hackers), chuckr@glue.umd.edu (Chuck Robey), joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch) Subject: Re: motherboard chipset identification In-reply-to: Your message of "Sat, 09 Nov 1996 00:03:02 +0100." <199611082303.AAA05902@x14.mi.uni-koeln.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 08 Nov 1996 16:21:09 -0700 Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Hi all, >What does it depend on ? > >Why can't you probe for it ? >(Does a probe lock up the system if the wrong flavor is assumed ?) In general they use a register indirection scheme, write the index to IOREGSEL, then read/write the data from/to IODATA. several flavors want you to do a BYTE write to IOREGSEL, while others specify a DWORD (ie long) write to IOREGSEL. The system doesn't lock up, but the IO APIC of the DWORD flavor type doesn't work for us either. Right now the board's owner is helping me sort it all out, but in the long run I would like a more elegant solution than "poke it and see if it pukes". It would be nice to know which flavor it is b4 the first access. My experience with hardware says that even if I find that a particular piece of silicon can be probed "incorrectly" to determine what it can do without perturbing it, another instance of the same part made in the past or the future might not be so forgiving.... That's one of the things that makes this kind of work so fun! -- Steve Passe | powered by smp@csn.net | FreeBSD -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6.2 mQCNAzHe7tEAAAEEAM274wAEEdP+grIrV6UtBt54FB5ufifFRA5ujzflrvlF8aoE 04it5BsUPFi3jJLfvOQeydbegexspPXL6kUejYt2OeptHuroIVW5+y2M2naTwqtX WVGeBP6s2q/fPPAS+g+sNZCpVBTbuinKa/C4Q6HJ++M9AyzIq5EuvO0a8Rr9AAUR tBlTdGV2ZSBQYXNzZSA8c21wQGNzbi5uZXQ+ =ds99 -----END PGP PUBLIC KEY BLOCK-----