From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from manexowa.empirix.com (unknown [66.151.190.243]) by ozlabs.org (Postfix) with ESMTP id A8079B7B83 for ; Wed, 23 Sep 2009 21:56:32 +1000 (EST) From: "Morrison, Tom" To: Benjamin Herrenschmidt Date: Wed, 23 Sep 2009 07:56:27 -0400 Subject: RE: PCI HotPlug and Adding Resources after Linux Boots Message-ID: <80955630EE34634AB5030FB8CE9BDCEFD74DA18D@EXBEDCLST.empirix.com> References: <80955630EE34634AB5030FB8CE9BDCEFD7459DF2@EXBEDCLST.empirix.com> <1253698927.7103.312.camel@pasglop> In-Reply-To: <1253698927.7103.312.camel@pasglop> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Cc: "linuxppc-dev@ozlabs.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Thank you for taking the time in confirming some of the=20 potential strategies I was already thinking about...:-) I am going to try to pre-allocate some resources for the specific port/slot/bridge device (because we know at all times that port #6 (bus #5) is going to have a FPGA end device associated with it... Any other thoughts - whenever you can make them - would be more than welcome! Tom >> -----Original Message----- >> From: Benjamin Herrenschmidt [mailto:benh@kernel.crashing.org] >> Sent: Wednesday, September 23, 2009 5:42 AM >> To: Morrison, Tom >> Cc: linuxppc-dev@ozlabs.org; linux-kernel@vger.kernel.org >> Subject: Re: PCI HotPlug and Adding Resources after Linux Boots >>=20 >> On Tue, 2009-09-22 at 15:36 -0400, Morrison, Tom wrote: >> > I am not exactly sure who to direct this question to (general Linux >> > kernel or LinuxPPC), >>=20 >> PCI Hotplug is reasonably arch specific at the moment so I suppose >> here's is as good as anywhere else to ask :-) >>=20 >> > so I am directing to both - in hopes that someone will recognize this >> > problem - and perhaps >> > >> > give me some suggestions on how to proceed... >>=20 >> There's a few things you can do, though I don't have time just right now >> to give you a detailed answer. I'll try again later. >>=20 >> In the meantime, some of the answers could be around not using full >> automatic resource assignment, but instead, pre-initializing the top >> bridge with some resources that are going to be enough for the device. >>=20 >> You can also try to get the bridge to re-allocate. There's various funky >> locking issues with doing that though as long as it's during boot time, >> it's not too much of a problem. >>=20 >> There are other more or less hackish ways to do it, but I'll have to >> give it more thought. >>=20 >> I'm quite stretched at the moment so if you don't hear back from me in >> the upcoming few days, don't hesitate to ping me again. >>=20 >> Cheers, >> Ben. >> > >> > I am running Linux (2.6.23x (and 2.6.27.x)) on a MPC8572 based system. >>=20 [Morrison, Tom]=20