From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sunset.davemloft.net (74-93-104-97-Washington.hfc.comcastbusiness.net [74.93.104.97]) by ozlabs.org (Postfix) with ESMTP id 17B08DDF7B for ; Wed, 20 May 2009 05:05:19 +1000 (EST) Date: Tue, 19 May 2009 12:05:14 -0700 (PDT) Message-Id: <20090519.120514.26253637.davem@davemloft.net> To: arnd@arndb.de Subject: Re: Musings on PCI busses From: David Miller In-Reply-To: <200905191812.03347.arnd@arndb.de> References: <200905191812.03347.arnd@arndb.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Cc: linuxppc-dev@ozlabs.org, thunderbird2k@gmail.com, John.Linn@xilinx.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Arnd Bergmann Date: Tue, 19 May 2009 18:12:02 +0200 > On Tuesday 19 May 2009, Grant Likely wrote: >> 1) Probe the host controller in an of_platform driver. =A0This has t= he >> advantage of simplicity. =A0The probe routine will get automatically= >> called when the PCI host controller device tree node is registered >> with the of_platform bus. =A0The bus parenthood also gets reflected = in >> the device model and sysfs. =A0The disadvantage is that it defers PC= I >> bus probing until after the of_platform bus is probed (maybe this is= >> okay; maybe this already happens anyway). > = > This is also what we do on 64-bit systems (well, Cell at this time). > There are no fundamental problems with this, just some slightly > unexpected interactions e.g. when you have use a PCI serial port > as your console before probing PCI. This is also what sparc64 does :-) All of the individual sparc64 PCI controller types have a OF driver and then there is a common layer of OF PCI helper code to do most of the work.