Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754812AbYAPXhr (ORCPT ); Wed, 16 Jan 2008 18:37:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752511AbYAPXhi (ORCPT ); Wed, 16 Jan 2008 18:37:38 -0500 Received: from smtpq1.tilbu1.nb.home.nl ([213.51.146.200]:50016 "EHLO smtpq1.tilbu1.nb.home.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751903AbYAPXhh (ORCPT ); Wed, 16 Jan 2008 18:37:37 -0500 Message-ID: <478E946D.9040105@keyaccess.nl> Date: Thu, 17 Jan 2008 00:34:05 +0100 From: Rene Herman User-Agent: Thunderbird 2.0.0.9 (X11/20071031) MIME-Version: 1.0 To: "H. Peter Anvin" CC: 7eggert@gmx.de, Bjorn Helgaas , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Russell King , Jeff Garzik , Andrew Morton , Alan Cox Subject: Re: [patch 2/2] 8250_pnp: register x86 COM ports at the conventional ttyS names References: <9MjWa-VI-9@gated-at.bofh.it> <9MjWb-VI-11@gated-at.bofh.it> <9MlEG-3Mx-13@gated-at.bofh.it> <9Mmra-56f-29@gated-at.bofh.it> <478E6C20.2030005@zytor.com> In-Reply-To: <478E6C20.2030005@zytor.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -1.0 (-) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1355 Lines: 31 On 16-01-08 21:42, H. Peter Anvin wrote: > Bodo Eggert wrote: >> >> BTW1: These addresses may be used to detect ports on non-standard >> addresses, but unfortunately they don't tell the IRQ. >> >> BTW2: When I submitted a patch using the BIOS data area, I was told >> that it might not exist on systems booting from non-PC firmware. This >> claim was not yet backed with any knowledge, nor did anybody suggest a >> way to detect this situation. > > This is, of course, true. It doesn't exactly help that some (most?) > non-PC firmware at least mimic the BIOS data area. > > In this particular case, there is some minor sanity-checking that can be > done: the values should be nonzero and aligned 8. The number of places expected to contain something sensible should I believe first be verified at 0x410 -- the equipment word. Bits 11-9 (0x0e00) should be the number of serial ports, 0 to 4 (so 5-7 is also a sanity check) and if BIOSes can be expected to zero out the non-used base-addresses (at 0x400, 0x402, 0x404, 0x406) that's another sanity check. Don't know if they can though... Rene. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/