On Mon, Apr 23, 2018 at 02:11:40PM +0100, Peter Maydell wrote: > On 23 April 2018 at 06:18, Jan Kiszka <jan.kis...@web.de> wrote: > > From: Jan Kiszka <jan.kis...@siemens.com> > > > > This allows to pin the host controller in the Linux PCI domain space. > > Linux requires that property to be available consistently or not at all, > > in which case the domain number becomes unstable on additions/removals. > > Adding it here won't make a difference in practice for most setups as we > > only expose one controller. > > > > However, enabling Jailhouse on top may introduce another controller, and > > that one would like to have stable address as well. So the property is > > needed for the first controller as well. > > Am I right in thinking that for ACPI the PCI domain number is > communicated via the _SEG method? If so, looks like we already > set that, and we set it to 0, which matches what we're doing here > in the DT, so that's good.
_SEG and linux,pci-domain are similar in definition, but don't appear to be equivalent, as the same _SEG number is permitted across multiple host bridges, but linux,pci-domain must be unique for each host bridge. I think the (_SEG, _BBN) pair may form the equivalent. We also set _BBN to zero, so I think we're fine anyway. > > > Signed-off-by: Jan Kiszka <jan.kis...@siemens.com> > > --- > > hw/arm/virt.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > > index 94dcb125d3..943371b75e 100644 > > --- a/hw/arm/virt.c > > +++ b/hw/arm/virt.c > > @@ -1023,6 +1023,7 @@ static void create_pcie(const VirtMachineState *vms, > > qemu_irq *pic) > > qemu_fdt_setprop_string(vms->fdt, nodename, "device_type", "pci"); > > qemu_fdt_setprop_cell(vms->fdt, nodename, "#address-cells", 3); > > qemu_fdt_setprop_cell(vms->fdt, nodename, "#size-cells", 2); > > + qemu_fdt_setprop_cell(vms->fdt, nodename, "linux,pci-domain", 0); > > qemu_fdt_setprop_cells(vms->fdt, nodename, "bus-range", 0, > > nr_pcie_buses - 1); > > qemu_fdt_setprop(vms->fdt, nodename, "dma-coherent", NULL, 0); > > -- > > Drew -- is minor changes to the DTC something we can do without > having to condition it on machine version? I forget... Yes, and even less minor changes than this one can be made to ACPI and DT generation, per the "if a firwmare update could change it, then don't worry about it" policy. (I've CC'ed Igor in case he wants to chime in to correct anything I've said.) Thanks, drew
