On Thu, Oct 11, 2012 at 11:34:08AM -0400, Jason Baron wrote: > On Thu, Oct 11, 2012 at 04:46:56PM +0200, Michael S. Tsirkin wrote: > > On Thu, Oct 11, 2012 at 10:21:22AM -0400, Jason Baron wrote: > > > On Thu, Oct 11, 2012 at 12:57:06PM +0200, Michael S. Tsirkin wrote: > > > > On Mon, Oct 08, 2012 at 11:30:39PM -0400, Jason Baron wrote: > > > > > From: Jason Baron <jba...@redhat.com> > > > > > > > > > > Add piix style acpi hotplug to q35. > > > > > > > > > > Signed-off-by: Jason Baron <jba...@redhat.com> > > > > > > > > Something I don't understand here: this only handles hotplug > > > > of devices behind the root, no? > > > > Don't we need support for hotplug/hot remove of devices behind > > > > bridges? > > > > > > > > > > Yes, this only handles acpi hotplug of devices behind the root. I'm > > > trying to reach minimal set of q35 patches that we can build upon. I > > > think that this patch gives us at least the same functionality as piix > > > does. (Plus there is pcie hotplug). > > > > > > As you know, I have a proof of concept patch series providing a second > > > level of hotplug behind bridges. Unfortunately, it was based on the > > > static acpi tables, before Paolo made the hotplug table generation > > > dynamic. So it needs quite a bit of re-work. But I know that it should > > > work :) > > > > > > Thanks, > > > > > > -Jason > > > > Yes. Reason I ask is because q35 is adding bridges by default now. > > Would it be possible to only add them if requested on command line by user > > instead? I realize some guests expect devices at specific slots > > but this does not apply to bridges I think? > > > > I just tried out getting rid of the bridges by default. > > So 'lspci' goes from: > > 00:00.0 Host bridge: Intel Corporation 82G33/G31/P35/P31 Express DRAM > Controller > 00:01.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:02.0 VGA compatible controller: Cirrus Logic GD 5446 > 00:03.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet > Controller (rev 03) > 00:17.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:18.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.1 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.2 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.3 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.4 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.5 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 92) > 00:1f.0 ISA bridge: Intel Corporation 82801IB (ICH9) LPC Interface Controller > (rev 02) > 00:1f.2 SATA controller: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 6 port > SATA AHCI Controller (rev 02) > 00:1f.3 SMBus: Intel Corporation 82801I (ICH9 Family) SMBus Controller (rev > 02) > 03:00.0 PCI bridge: Texas Instruments XIO3130 PCI Express Switch (Upstream) > (rev 02) > 04:00.0 PCI bridge: Texas Instruments XIO3130 PCI Express Switch (Downstream) > (rev 01) > 0c:1c.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) > 0c:1d.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) > 0c:1e.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) > 0c:1f.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) > > To: > > 00:00.0 Host bridge: Intel Corporation 82G33/G31/P35/P31 Express DRAM > Controller > 00:01.0 VGA compatible controller: Cirrus Logic GD 5446 > 00:02.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet > Controller (rev 03) > 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 92) > 00:1f.0 ISA bridge: Intel Corporation 82801IB (ICH9) LPC Interface Controller > (rev 02) > 00:1f.2 SATA controller: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 6 port > SATA AHCI Controller (rev 02) > 00:1f.3 SMBus: Intel Corporation 82801I (ICH9 Family) SMBus Controller (rev > 02) > > > Windows and Linux guests seem fine with either layout. Slots 1-2 are > specific to my setup. So this is a pretty minimal set.
I guess we can remove the PCI bridge too? One interesting side effect here is that there are less free pci slots on root bus now. I guess at minimum management needs to be taught about this, and I'm not sure how. > I think that providing the minimal set of devices is good, since it > allows the user to configure things as much as possible. So I am in > favor of this more minimal set. My only hesitation is that we pull out, > or that I have not included some important piece h/w at a specific slot > that a guest might need. Thus potentially breaking existing setups. > Perhaps, that might mean a new machine type in the future, if we've > messed up? Yes, that's one solution. > These devices and slots are pulled from the Intel docs on ICH9 and Q35 > specs. See: > > http://www.intel.com/content/www/us/en/io/io-controller-hub-9-datasheet.html > > Perhaps, Yamahata can comment further on the specific set of bridges? > > > It would also be nice to add comments explaining why > > specific slots were selected e.g. /* BSD XYZ fails to boot unless ahci is > > at alow 2 */ > > etc. > > Right, its basically just pulled from the Intel spec as mentioned above. > > > > > Also - will adding this code now mean that when adding bridges > > we'll need to add compatibility code in bios/qemu in the future? > > > > I don't think so, but maybe you can elaborate this concern more > specifically? > > Thanks, > > -Jason Just this: can same bios work on this interface and the one you intend for hotplug behind bridge? Or will we need to version interface? -- MST
