From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Hancock Subject: Re: Sata link_power_management_policy questions Date: Mon, 22 Jun 2009 23:12:27 -0600 Message-ID: <4A40643B.7090805@gmail.com> References: <4A3FD261.7060903@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-gx0-f214.google.com ([209.85.217.214]:40145 "EHLO mail-gx0-f214.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752157AbZFWFLv (ORCPT ); Tue, 23 Jun 2009 01:11:51 -0400 In-Reply-To: <4A3FD261.7060903@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Patrick Voegeli Olivera Cc: "linux-acpi@vger.kernel.org" , ide On 06/22/2009 12:50 PM, Patrick Voegeli Olivera wrote: > Hi there, > > I have a laptop with Sata set to native mode and ahci enabled in the > bios. In ubuntu, I can see > /sys/class/scsi_host/host0/link_power_management_policy for host0, host1 > and host2, but if I read any of those using cat they always will return > max_performance, even if I echo min_power or medium_power and it gives > no errors: > > root@patrick-laptop:~# cat > /sys/class/scsi_host/host0/link_power_management_policy > max_performance > root@patrick-laptop:~# echo min_power > > /sys/class/scsi_host/host0/link_power_management_policy > root@patrick-laptop:~# cat > /sys/class/scsi_host/host0/link_power_management_policy > max_performance > > I've tried to look around for a solution, but I haven't found anything > useful. Is this a feature that depends on the HDD? Does the hard drive > need to be sata 2/300 or should it also work with sata 1/150? Is it just > that my laptop doesn't support it? > > Since my HDD is sata150, I've tried with another HDD and I had the same > problem. I don't know if it was sata2 compliant, though. > > My laptop has intel chipsets. Namely, the 965gm (with x3100 graphics) > northbridge and I think it has a ich8 southbridge. > > Any ideas on what to try? Please post your dmesg output and hdparm -I output for the drive. Also cc-ing linux-ide.