From owner-freebsd-acpi@FreeBSD.ORG Fri Sep 18 15:05:09 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 701091065676; Fri, 18 Sep 2009 15:05:09 +0000 (UTC) (envelope-from bf1783@googlemail.com) Received: from mail-ew0-f208.google.com (mail-ew0-f208.google.com [209.85.219.208]) by mx1.freebsd.org (Postfix) with ESMTP id 4B8938FC08; Fri, 18 Sep 2009 15:05:07 +0000 (UTC) Received: by ewy4 with SMTP id 4so539931ewy.36 for ; Fri, 18 Sep 2009 08:05:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:date:message-id:subject :from:to:cc:content-type; bh=tzy1F1uO5pgodZvxTKxSoW2T8fyI2dHp/uGZ8EI8jQE=; b=FnvXNfloK2weBqDYw2YKjPedCZtTbilDNVsiN4L/LZOvNCrX4QNyx6qTr9q42J3pyo ciPdqP2Zul77y6KsyH923XGIHNj5eCyPt8Cf71Yy3E+b703eKQH0iDDXPEIX0rbHJmgk YDN7vaDCxhWjgXs3O7heiLjS6Ut93ELSsijKU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:cc:content-type; b=EOfjoSj0ed0Rid+qNLkmn1NcuHbBhFnfteS7jarGTCD7iWzw6+Nons2Aw/+tQ19X6C TlMBLi9JWEGu7ZJo0rSWh1zWnRuCZni2yt8j9mFjaq1FQr2k6qG5WGbUfKn7IbAvgNkh yYfbDefCaBQPH8ZIBd0vGoEyp36b+IOGvHAzg= MIME-Version: 1.0 Received: by 10.216.53.65 with SMTP id f43mr527404wec.145.1253286307168; Fri, 18 Sep 2009 08:05:07 -0700 (PDT) Date: Fri, 18 Sep 2009 15:05:06 +0000 Message-ID: From: "b. f." To: freebsd-acpi@FreeBSD.org Content-Type: text/plain; charset=ISO-8859-1 Cc: mav@FreeBSD.org, jkim@FreeBSD.org, brueffer@FreeBSD.org, jhb@FreeBSD.org Subject: acpi(4) corrections, clarifications 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: Fri, 18 Sep 2009 15:05:09 -0000 While this documentation cleanup is going on, I'd like to point out that acpi(4) could use some improvements: (1)In the "SYSCTL VARIABLES" section, under hw.acpi.cpu.cx_lowest, acpi(4) states "To enable ACPI CPU idling control, machdep.cpu_idle_hlt must be set to 1". However, apparently only the pc98 port still uses this OID, while amd64, i386, etc., use something like machdep.idle=hlt, so this remark should be changed. And in any case, is this statement correct? Can't idling now be used with other values of machdep.idle, like mwait, mwait_hlt, amdc1e, hlt, and acpi? (2)Under the "BUGS" section, acpi(4) states: "The acpi CPU idle power management drive conflicts with the local APIC (LAPIC) timer. Disable APIC mode with hint.apic.0.disabled or do not use the C2 and C3 states if APIC mode is enabled." However, mav@, in his recent series of recommendations on power-saving, advocated the use of hints like hint.apic.0.clock="0" instead. Is simply turning off the timer sufficient to use the deeper sleep states, or must all of the local apic be disabled? Some machines won't boot with hint.apic.0.disabled, so it would be useful to determine whether this is really necessary. Regards, b.