From patchwork Wed Nov 24 02:37:25 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 72786 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id BFA2CB708B for ; Wed, 24 Nov 2010 13:38:39 +1100 (EST) Received: from localhost ([127.0.0.1]:34322 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PL5Fj-0005xH-VW for incoming@patchwork.ozlabs.org; Tue, 23 Nov 2010 21:38:36 -0500 Received: from [140.186.70.92] (port=46521 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PL5Ei-0005fK-N1 for qemu-devel@nongnu.org; Tue, 23 Nov 2010 21:37:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PL5Eh-0006B3-6s for qemu-devel@nongnu.org; Tue, 23 Nov 2010 21:37:32 -0500 Received: from mail.valinux.co.jp ([210.128.90.3]:43147) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PL5Eg-0006Ar-Ho for qemu-devel@nongnu.org; Tue, 23 Nov 2010 21:37:31 -0500 Received: from ps.local.valinux.co.jp (vagw.valinux.co.jp [210.128.90.14]) by mail.valinux.co.jp (Postfix) with SMTP id 5086D27E9E; Wed, 24 Nov 2010 11:37:25 +0900 (JST) Received: (nullmailer pid 5313 invoked by uid 1000); Wed, 24 Nov 2010 02:37:25 -0000 Date: Wed, 24 Nov 2010 11:37:25 +0900 From: Isaku Yamahata To: "Michael S\. Tsirkin" Message-ID: <20101124023725.GC9591@valinux.co.jp> References: <20101122075402.GA6892@redhat.com> <20101122104337.GB24265@valinux.co.jp> <20101122225312.GA1359@redhat.com> <20101123181026.GA2752@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20101123181026.GA2752@redhat.com> User-Agent: Mutt/1.5.19 (2009-01-05) X-Virus-Scanned: clamav-milter 0.95.2 at va-mail.local.valinux.co.jp X-Virus-Status: Clean X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) Cc: skandasa@cisco.com, etmartin@cisco.com, wexu2@cisco.com, qemu-devel@nongnu.org, kraxel@redhat.com, pbonzini@redhat.com Subject: [Qemu-devel] Re: [PATCH v2 0/6] qdev reset refactoring and pci bus reset X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org On Tue, Nov 23, 2010 at 08:10:26PM +0200, Michael S. Tsirkin wrote: > On Tue, Nov 23, 2010 at 12:53:12AM +0200, Michael S. Tsirkin wrote: > > On Mon, Nov 22, 2010 at 07:43:37PM +0900, Isaku Yamahata wrote: > > > On Mon, Nov 22, 2010 at 09:54:02AM +0200, Michael S. Tsirkin wrote: > > > > On Fri, Nov 19, 2010 at 06:55:57PM +0900, Isaku Yamahata wrote: > > > > > Here is v2. I updated the comments, and dropped the pci qdev reset patch. > > > > > > > > > > Patch description: > > > > > The goal of this patch series is to implement secondary bus reset > > > > > emulation in pci-to-pci bridge. > > > > > At first, this patch series refactors qdev reset, > > > > > and then cleans up pci bus reset. Lastly implements pci bridge control > > > > > secondary bus reset bit. > > > > > > > > > > This patch series is for pci bus reset, which is ported > > > > > from the following repo. > > > > > git://repo.or.cz/qemu/aliguori.git qdev-refactor > > > > > > > > I've put the series on my pci branch, tweaking patches 5 and 6 in the > > > > process. Out of time to compile-tested only for now. > > > > > > Thank you. The tweaking looks good. > > > Do you still want me to send another patch to add a comment on RST#? > > > > OK, I got response, and yes, we need to fix code to avoid claiming > > transactions by devices on the secondary bus while secondary bus is in > > RST# for both pci and express. > > I guess the following fixes it? Almost. The following if claouse also needs modification. commit 120fe782a198b787e13a9d4681afae8dc66dee50 Author: "Michael S. Tsirkin" Date: Wed Nov 24 11:34:59 2010 +0900 pci: don't access bus while it's reset Devices on a bus should not respond while RST# is asserted, which is controlled by PCI_BRIDGE_CTL_BUS_RESET. Simply skip such a bus when propagating the configuration cycle. Signed-off-by: Michael S. Tsirkin Signed-off-by: Isaku Yamahata diff --git a/hw/pci.c b/hw/pci.c index d02f980..e7df612 100644 --- a/hw/pci.c +++ b/hw/pci.c @@ -1554,7 +1554,9 @@ PCIBus *pci_find_bus(PCIBus *bus, int bus_num) /* try child bus */ if (!bus->parent_dev /* host pci bridge */ || - (bus->parent_dev->config[PCI_SECONDARY_BUS] < bus_num && + (!(pci_get_word(bus->parent_dev->config + PCI_BRIDGE_CONTROL) & + PCI_BRIDGE_CTL_BUS_RESET) /* Don't walk the bus if it's reset. */ && + bus->parent_dev->config[PCI_SECONDARY_BUS] < bus_num && bus_num <= bus->parent_dev->config[PCI_SUBORDINATE_BUS])) { for (; bus; bus = sec) { QLIST_FOREACH(sec, &bus->child, sibling) { @@ -1562,8 +1564,11 @@ PCIBus *pci_find_bus(PCIBus *bus, int bus_num) if (sec->parent_dev->config[PCI_SECONDARY_BUS] == bus_num) { return sec; } - if (sec->parent_dev->config[PCI_SECONDARY_BUS] < bus_num && - bus_num <= sec->parent_dev->config[PCI_SUBORDINATE_BUS]) { + if (pci_get_word(sec->parent_dev->config + + PCI_BRIDGE_CONTROL) & PCI_BRIDGE_CTL_BUS_RESET + /* Don't walk the bus if it's reset. */ || + bus_num < sec->parent_dev->config[PCI_SECONDARY_BUS] || + sec->parent_dev->config[PCI_SUBORDINATE_BUS] < bus_num) { break; } }