From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [patch 3/3] Enable Aggressive Link Power management for AHCI controllers. Date: Mon, 11 Jun 2007 16:01:13 -0400 Message-ID: <466DAA09.7090000@garzik.org> References: <20070611184146.448266229@intel.com> <20070611114839.907bcae2.kristen.c.accardi@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:47904 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754019AbXFKUBQ (ORCPT ); Mon, 11 Jun 2007 16:01:16 -0400 In-Reply-To: <20070611114839.907bcae2.kristen.c.accardi@intel.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Kristen Carlson Accardi Cc: james.bottomley@steeleye.com, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, htejun@gmail.com, arjan@linux.intel.com Kristen Carlson Accardi wrote: > This patch will set the correct bits to turn on Aggressive > Link Power Management (ALPM) for the ahci driver. This > will cause the controller and disk to negotiate a lower > power state for the link when there is no activity (see > the AHCI 1.x spec for details). This feature is mutually > exclusive with Hot Plug, so when ALPM is enabled, Hot Plug > is disabled. ALPM will be enabled by default, but it is > settable via the scsi host syfs interface. Possible > settings for this feature are: > > Setting Effect > ---------------------------------------------------------- > min_power ALPM is enabled, and link set to enter > lowest power state (SLUMBER) when idle > Hot plug not allowed. > > max_performance ALPM is disabled, Hot Plug is allowed > > medium_power ALPM is enabled, and link set to enter > second lowest power state (PARTIAL) when > idle. Hot plug not allowed. > > Signed-off-by: Kristen Carlson Accardi seems OK at first glance, though I'll have questions about hardware behavior once I get off this day-long Intel conference call :)