From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id E338FB7069 for ; Sat, 21 Apr 2012 07:20:25 +1000 (EST) Message-ID: <1334956816.3197.24.camel@pasglop> Subject: Re: pci node question From: Benjamin Herrenschmidt To: Kumar Gala Date: Sat, 21 Apr 2012 07:20:16 +1000 In-Reply-To: References: <9F6FE96B71CF29479FF1CDC8046E1503346013@039-SN1MPN1-002.039d.mgd.msft.net> <4F91B335.4010501@freescale.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: Scott Wood , "linuxppc-dev@lists.ozlabs.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 2012-04-20 at 15:37 -0500, Kumar Gala wrote: > > What does this node represent in the first place? Is there really a > > PCI-to-PCI bridge? Are all other PCI devices underneath it? > > PCIe has this concept of a "virtual" bridge between the root-comples, > so that is what the node represents. Its always been a bit confusing > to me as its not 100% standardized by PCI sig. It actually is. The root complex virtual p2p is absolutely part of the standard. Cheers, Ben.