From owner-freebsd-hackers Mon Jun 1 01:11:27 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id BAA21568 for freebsd-hackers-outgoing; Mon, 1 Jun 1998 01:11:27 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from nlsystems.com (nlsys.demon.co.uk [158.152.125.33]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id BAA21562 for ; Mon, 1 Jun 1998 01:11:22 -0700 (PDT) (envelope-from dfr@nlsystems.com) Received: from herring.nlsystems.com (herring.nlsystems.com [10.0.0.2]) by nlsystems.com (8.8.8/8.8.5) with SMTP id JAA00450; Mon, 1 Jun 1998 09:11:41 +0100 (BST) Date: Mon, 1 Jun 1998 09:11:41 +0100 (BST) From: Doug Rabson To: Jason Thorpe cc: Curt Sampson , Mike Smith , hackers@FreeBSD.ORG Subject: Re: AlphaBIOS documentation In-Reply-To: <199806010743.AAA20008@lestat.nas.nasa.gov> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Mon, 1 Jun 1998, Jason Thorpe wrote: > On Mon, 1 Jun 1998 00:24:23 -0700 (PDT) > Curt Sampson wrote: > > > There's plenty of device driver source code in Linux and NetBSD, too. :-) > > > > My point is, every time a new type of Alpha comes along, you have > > to write new PALcode and compile it in to the boot loader. This is > > not really all that different than having to write and compile in > > a new device driver every time a new device comes along. > > Not really. Once you have working PALcode for a given platform, you never > have to touch it again. This is not true with drivers, which may need > modification for the next rev of a device. > > Also, the VAST majority of PALcode is common from one platform to another. > Usually, the only differences are in the interrupt routing code, and these > differences are usually very minor (esp. between same implementation revs, > e.g. two 21064-based systems or two 21164-based systems). The other main > difference is in the code that builds the CPU logout area; this code usually > copies platform-specific core logic registers. However, this will be the > same between two platforms which use the same core logic chipset (e.g. > the AlphaStation 500 and the AlphaPC 164, both of which use an ALCOR2). > > However, it is worth noting that the MILO PALcode doesn't actually work > very well, and doesn't implement an interface completely compatible with > the OSF/1 PALcode shipped with the SRM (logout area is different, for > example, and some exception vectors are different). > > In other words, I wouldn't exactly recommend using the MILO PALcode as a base. Point taken. I am going to try to buy a copy of the EBSDK. Maybe that will have more up-to-date code in it. I still think that DEC should put a copy of the OSF palcode into AlphaBIOS. -- Doug Rabson Mail: dfr@nlsystems.com Nonlinear Systems Ltd. Phone: +44 181 951 1891 Fax: +44 181 381 1039 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message