Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262603AbUKLSf5 (ORCPT ); Fri, 12 Nov 2004 13:35:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262605AbUKLSf5 (ORCPT ); Fri, 12 Nov 2004 13:35:57 -0500 Received: from colo.lackof.org ([198.49.126.79]:4015 "EHLO colo.lackof.org") by vger.kernel.org with ESMTP id S262603AbUKLSfu (ORCPT ); Fri, 12 Nov 2004 13:35:50 -0500 Date: Fri, 12 Nov 2004 11:35:47 -0700 From: Grant Grundler To: Michael Chan Cc: Andi Kleen , linux-kernel@vger.kernel.org, linux-pci@atrey.karlin.mff.cuni.cz, akpm@osdl.org, greg@kroah.com, "Durairaj, Sundarapandian" Subject: Re: [PATCH] pci-mmconfig fix for 2.6.9 Message-ID: <20041112183547.GA8828@colo.lackof.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=unknown-8bit Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.3.28i X-Home-Page: http://www.parisc-linux.org/ Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1717 Lines: 41 On Fri, Nov 12, 2004 at 09:52:17AM -0800, Michael Chan wrote: > On Wednesday, November 10, 2004 11:58 PM Andi Kleen wrote: > > Where is it guaranteed that these writes are non posted? > > Intel chipset engineer confirmed that they are non-posted. Michael, Thanks for digging that up. I think Andi was looking for references to the PCI-E spec. I found such a statement in "PCI Express(TM) Base Specification Revision 1.0a". Table 2-3 on page 47 says: | Cpl 00 0 1010 Completion without Data ? Used for I/O and | Configuration Write Completions and Read | Completions (I/O, Configuration, or | Memory) with Completion Status other than | Successful Completion. Section "2.2. Transaction Layer Protocol - Packet Definition" | Transactions are carried using Requests and Completions. Completions | are used only where required, for example, to return read data, or | to acknowledge Completion of I/O and Configuration Write Transactions. | Completions are associated with their corresponding Requests by the value | in the Transaction ID field of the Packet header. And "2.6.1 Flow Control Rules": | Flow Control distinguishes three types of TLPs (note relationship | to ordering rules ? see Section 2.4): | ? Posted Requests (P) ? Messages and Memory Writes | ? Non-Posted Requests (NP) ? All Reads, I/O, and Configuration Writes | ? Completions (CPL) ? Associated with corresponding NP Requests hth, grant - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/