From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick Voegeli Olivera Subject: Sata link_power_management_policy questions Date: Mon, 22 Jun 2009 20:50:09 +0200 Message-ID: <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-ew0-f210.google.com ([209.85.219.210]:37789 "EHLO mail-ew0-f210.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751547AbZFVSuR (ORCPT ); Mon, 22 Jun 2009 14:50:17 -0400 Received: by ewy6 with SMTP id 6so4943890ewy.37 for ; Mon, 22 Jun 2009 11:50:18 -0700 (PDT) Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "linux-acpi@vger.kernel.org" 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? # lspci 00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 03) 00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03) 00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03) 00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 03) 00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 03) 00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03) 00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03) 00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03) 00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 03) 00:1c.2 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 3 (rev 03) 00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03) 00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03) 00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 03) 00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03) 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3) 00:1f.0 ISA bridge: Intel Corporation 82801HEM (ICH8M) LPC Interface Controller (rev 03) 00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 03) 00:1f.2 SATA controller: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA AHCI Controller (rev 03) 00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 03) 04:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8055 PCI-E Gigabit Ethernet Controller (rev 14) 06:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG [Golan] Network Connection (rev 02) Thanks, any input will be welcome.