From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:34455) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RLA0S-0003dq-4k for qemu-devel@nongnu.org; Tue, 01 Nov 2011 04:47:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RLA0R-0005K8-1E for qemu-devel@nongnu.org; Tue, 01 Nov 2011 04:47:40 -0400 Received: from [222.73.24.84] (port=59473 helo=song.cn.fujitsu.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RLA0N-00056e-63 for qemu-devel@nongnu.org; Tue, 01 Nov 2011 04:47:38 -0400 Message-ID: <4EAFB284.1010601@cn.fujitsu.com> Date: Tue, 01 Nov 2011 16:49:08 +0800 From: Wen Congyang MIME-Version: 1.0 References: <20110704094358.GA10960@redhat.com> <4E801927.8020708@cn.fujitsu.com> <20110926070824.GB5860@redhat.com> <4EAF4AFD.6040102@cn.fujitsu.com> <20111101084439.GA11958@redhat.com> In-Reply-To: <20111101084439.GA11958@redhat.com> Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1 Subject: Re: [Qemu-devel] [PATCH] pci: add standard bridge device List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: qemu-devel At 11/01/2011 04:44 PM, Michael S. Tsirkin Write: > On Tue, Nov 01, 2011 at 09:27:25AM +0800, Wen Congyang wrote: >> Hi, Michael S. Tsirkin >> >> At 09/26/2011 03:08 PM, Michael S. Tsirkin Write: >>> On Mon, Sep 26, 2011 at 02:18:15PM +0800, Wen Congyang wrote: >>>> Hi, Michael S. Tsirkin >>>> >>>> At 07/04/2011 05:43 PM, Michael S. Tsirkin Write: >>>>> This adds support for a standard pci to pci bridge, >>>>> enabling support for more than 32 PCI devices in the system. >>>>> To use, specify the device id as a 'bus' option. >>>>> Example: >>>>> -device pci-bridge,id=bridge1 \ >>>>> -netdev user,id=u \ >>>>> -device ne2k_pci,id=net2,bus=bridge1,netdev=u >>>>> >>>>> TODO: device hotplug support. >>>> >>>> Do you have any plan to implement this? >>> >>> I think this will be needed before merging the bridge code. >> >> What will you plan to support? >> >> 1. all PCI-to-PCI bridge is not hotpluggable. >> host bridge >> | >> --------------------- >> | | >> bridge bridge <= *not* hotpluggable >> | | >> ----------- ------------ >> | | | | >> slot slot slot slot <= hotplug here >> >> >> 2. PCI-to-PCI bridge is hotpluggable. >> bridge >> | >> ------------------- >> | | >> bridge on slot bridge on slot <= hot-plug here >> | | >> ------- ------- >> | | | | >> slot slot slot slot <= hot-plug here >> >>> >>>> I read the qemu's code, and find that qemu uses PIIX4_PM to support >>>> pci device hot plugging on PCI bus 0. How to support it on the other >>>> bus? Add PIIX4_PM to each PCI bus or implement a new power management? >>>> >>>> Thanks >>>> Wen Congyang >>> >>> There are many valid options. One is shpc interface. >>> I started looking into this but got preempted by other >>> tasks. Hope to get back to this at some point. >> >> Some old OS does not support shpc. So I think it's better to use ACPI to do it. >> >> Currently, we get which device is removed or inserted by reading the I/O port >> 0xae00(length: 8 bytes), and _EJ0 method uses I/O port 0xae08(length: 4 bytes). >> How do we determine this I/O address? Is there any spec to describe it? >> >> Thanks >> Wen Congyang > > Can we discuss these questions on the mailing list? No problem. I have cced qemu mailing list. Thanks Wen Congyang