From owner-freebsd-acpi@FreeBSD.ORG Wed Dec 9 20:32:07 2009 Return-Path: Delivered-To: freebsd-acpi@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3ED21106568F; Wed, 9 Dec 2009 20:32:07 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 0DDC08FC08; Wed, 9 Dec 2009 20:32:07 +0000 (UTC) Received: from bigwig.baldwin.cx (66.111.2.69.static.nyinternet.net [66.111.2.69]) by cyrus.watson.org (Postfix) with ESMTPSA id B282646B29; Wed, 9 Dec 2009 15:32:06 -0500 (EST) Received: from jhbbsd.localnet (unknown [209.249.190.9]) by bigwig.baldwin.cx (Postfix) with ESMTPA id 09AA98A025; Wed, 9 Dec 2009 15:32:06 -0500 (EST) From: John Baldwin To: "Moore, Robert" Date: Wed, 9 Dec 2009 15:29:41 -0500 User-Agent: KMail/1.12.1 (FreeBSD/7.2-CBSD-20091103; KDE/4.3.1; amd64; ; ) References: <20091208060339.GK98273@pollux.cenkes.org> <200912080749.55710.jhb@freebsd.org> <4911F71203A09E4D9981D27F9D83085840DA9AC8@orsmsx503.amr.corp.intel.com> In-Reply-To: <4911F71203A09E4D9981D27F9D83085840DA9AC8@orsmsx503.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200912091529.41293.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0.1 (bigwig.baldwin.cx); Wed, 09 Dec 2009 15:32:06 -0500 (EST) X-Virus-Scanned: clamav-milter 0.95.1 at bigwig.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-2.5 required=4.2 tests=AWL,BAYES_00,RDNS_NONE autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on bigwig.baldwin.cx Cc: "freebsd-acpi@freebsd.org" , Andrew Pantyukhin Subject: Re: libi386/biosacpi.c - bad RSDP checksum search X-BeenThere: freebsd-acpi@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: ACPI and power management development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Dec 2009 20:32:07 -0000 On Wednesday 09 December 2009 1:46:36 pm Moore, Robert wrote: > Might be a dumb question, but why is the bootloader looking around for ACPI > tables in the first place? I think it only does so for two different reasons. First, it sets some kernel environment variables with the locations of the RSDP as well as the RSDT or XDST. The FreeBSD version of acpidump will then use these variables if they are set instead of walking memory to find the tables. The bigger reason is that on FreeBSD/i386 ACPI can be compiled as an optional kernel module (and until 8.0 it was provided as a module rather than statically compiled into the main kernel image by default), and that the loader will automatically load the ACPI module when loading a kernel if it detects that ACPI is present. This latter functionality is largely obsolete in FreeBSD 8.0 and later though since ACPI is now compiled into the kernel by default. -- John Baldwin