From owner-freebsd-alpha Sat Dec 4 16:24:32 1999 Delivered-To: freebsd-alpha@freebsd.org Received: from Twig.Rodents.Montreal.QC.CA (Twig.Rodents.Montreal.QC.CA [132.206.78.3]) by hub.freebsd.org (Postfix) with ESMTP id 4527C14DE5 for ; Sat, 4 Dec 1999 16:24:25 -0800 (PST) (envelope-from mouse@Twig.Rodents.Montreal.QC.CA) Received: (from mouse@localhost) by Twig.Rodents.Montreal.QC.CA (8.8.8/8.8.8) id TAA17128; Sat, 4 Dec 1999 19:24:19 -0500 (EST) Date: Sat, 4 Dec 1999 19:24:19 -0500 (EST) From: der Mouse Message-Id: <199912050024.TAA17128@Twig.Rodents.Montreal.QC.CA> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit To: port-alpha@netbsd.org, alpha@freebsd.org Subject: Re: Q: Compaq, *BSD and 'Linux-only' AlphaBIOS (fwd) Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org >> The PALcode included in MILO has severe bugs. You can't use it >> to run BSD, or OSF/1 for that matter. It's remarkable that you >> can use it to run Linux, and sundry reports of Linux >> instability when run with MILO make me suspect that, in fact, >> you can't. > In essence what you're saying is that no Alpha OS is capable of > actually talking to the bare hardware? e.g. PALcode is still > required after the kernel is loaded? As I understand it - I'm sure I'll be corrected if I'm wrong - that's correct. The PALcode is used by the OS for things which are severely hardware-dependent (like loading page table entries, I think), and I think the PALcode itself is very hardware-specific. (That is, it won't work to, for example, put AlphaPC164LX PALcode on anything but an AlphaPC164LX.) Very loosely put, custom microcode. :-) > e.g. Windows NT has PALcode embedded in it somehow? Possible, I suppose, but it strikes me as unlikely; more likely it knows how to call on the PALcode provided by ARC, just as *BSD knows how to call on the PALcode provided by SRM. > This sounds familiar, but I'm still confused about it. Why can't the > PALcode be reverse engineered, or otherwise re-written? It probably could be, but if I'm right about the degree to which it's hardware-specific, it likely wouldn't be worth it. > I have typically thought of the "SRM is required for NetBSD/alpha" > along the lines of "OpenFirmware is required for NetBSD/macppc." > [...] The impression I have now is more like "SRM is required for > NetBSD/alpha" along the lines of "BIOS is required for Windows." The latter is more or less the impression I have too, for what that may be worth. der Mouse mouse@rodents.montreal.qc.ca 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message