From owner-freebsd-questions@FreeBSD.ORG Wed Feb 4 20:50:32 2015 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id E63D8918 for ; Wed, 4 Feb 2015 20:50:32 +0000 (UTC) Received: from plane.gmane.org (plane.gmane.org [80.91.229.3]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id A0D672EB for ; Wed, 4 Feb 2015 20:50:32 +0000 (UTC) Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1YJ6tz-00083z-7i for freebsd-questions@freebsd.org; Wed, 04 Feb 2015 21:50:23 +0100 Received: from pool-173-79-82-127.washdc.fios.verizon.net ([173.79.82.127]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 04 Feb 2015 21:50:23 +0100 Received: from nightrecon by pool-173-79-82-127.washdc.fios.verizon.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 04 Feb 2015 21:50:23 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-questions@freebsd.org From: Michael Powell Subject: Re: Clarifications on ACPI driver Date: Wed, 04 Feb 2015 15:50:16 -0500 Lines: 46 Message-ID: References: <54D25DF1.9030603@netfence.it> Reply-To: nightrecon@hotmail.com Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7Bit X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: pool-173-79-82-127.washdc.fios.verizon.net X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 04 Feb 2015 20:50:33 -0000 Andrea Venturoli wrote: > Hello. > > I read in the handbook (12.13.1) "the acpi(4) driver is loaded by > default at system boot and should *not* be compiled into the kernel". > > Yet I see "device acpi" in GENERIC. This is only so for the 32-bit i386 build. You will not see this in the 64- bit x86_64 build. > Aren't those two things in contrast? My perception here is the confusion may arise from the 64-bit vs 32-bit systems; the above is applicable to the 64-bit build while a 32-bit build still uses the deprecated 'device acpi'. > Is the information in the handbook outdated? Wrong? > Does it mean something different to what I believe it means? > This could probably be improved in the Handbook by including the 32 vs 64 bit differences as outlined above. > > What is "options ACPI_DMAR"? What does it do? This I have no idea. > Is it ok to add "device acpi_video" to a kernel config? I don't know enough about ACPI in FreeBSD in general, but historically many acpi situations have been moreso a problem wrt to laptops. There are a few acpi modules that cover some specific laptop hardwares, but this is still not totally comprehensive. Some piece of the problem has been that manufacturers don't release the information the devs need. A quick perusal of man acpi_video looks like it may be useful in certain situations, most seemingly wrt to laptop display choosing and/or screen brightness. Since I do not run FreeBSD on a laptop I just don't know enough about this. In short, for a 32-bit system you could give it a try, but should you try to place 'device acpi' into a 64-bit build it will bomb. -Mike