From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Subject: Re: SATA hotplug not detecting new disks Date: Fri, 26 Jul 2013 14:12:22 -0700 Message-ID: <51F2E636.50001@sr71.net> References: <51F1B179.4070309@sr71.net> <51F1D63A.2010403@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from www.sr71.net ([198.145.64.142]:46756 "EHLO blackbird.sr71.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760311Ab3GZVMX (ORCPT ); Fri, 26 Jul 2013 17:12:23 -0400 In-Reply-To: <51F1D63A.2010403@intel.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Aaron Lu Cc: Tejun Heo , linux-ide@vger.kernel.org, LKML , Shane Huang On 07/25/2013 06:51 PM, Aaron Lu wrote: > On 07/26/2013 07:15 AM, Dave Hansen wrote: >> > I've got a relatively new system that doesn't seem to be able to hotplug >> > SATA disks. I see the same behavior on 3.10, 3.11-rc2, and Ubuntu's >> > 3.8.0-25-generic. The disks are detected right away on reboots, but >> > even after poking the /sys/class/scsi_host/host*/scan files, new disks >> > are never detected. I've disabled link power management. >> > >> > Am I doing something stupid here? I thought this "just worked" on my >> > previous hardware. > My vague memory reminds me that not all SATA ports are hot pluggable - > you can check the port's "External SATA port" bit and "Hot Plug Capable" > bit of the PxCMD register like this: > > $ grep ahci /proc/iomem > e1a40000-e1a407ff : ahci > # dd if=/dev/mem of=ahcidump bs=4096 count=1 skip=0xe1a40 > You will need to change 0xe1a40 to decimal format. > > Then the PxCMD is at offset 0x118 for port 0, check bit 21 for E-SATA or > bit 18 for hot pluggable bits. If any of them set to 1, this port > should be hot pluggable; otherwise, it doesn't have this capability. I went digging back through the BIOS settings, and found a nice checkbox to enable hotplug support on the ports. All seems happy now. Thanks for the help. I hope someone else googling will hit this thread. :)