This adds a devfn_max field to PCIBus and adds a pci_can_add_device()
function which, if no "addr" (aka devfn) is specified, will tell whether
there is any slot free between devfn_min and devfn_max.
This will be used by some PCI root complex implementations that support
only one direct child to avoid having qemu put dumb devices at different
slot numbers.
Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
---
hw/pci/pci.c | 22 ++++++++++++++++++++++
include/hw/pci/pci_bus.h | 1 +
2 files changed, 23 insertions(+)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 168b9cc..7003f7c 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -108,6 +108,27 @@ static uint16_t pcibus_numa_node(PCIBus *bus)
return NUMA_NODE_UNASSIGNED;
}
+static bool pci_can_add_device(BusState *bus, QemuOpts *opts)
+{
+ unsigned int devfn, max;
+ PCIBus *pbus = PCI_BUS(bus);
+
+ /* If address is specified, say yes and let it fail if that doesn't work */
+ if (qemu_opt_get(opts, "addr") != NULL) {
+ return true;
+ }
+ max = ARRAY_SIZE(pbus->devices);
+ if (pbus->devfn_max && pbus->devfn_max < max) {
+ max = pbus->devfn_max;
+ }
+ for (devfn = pbus->devfn_min ; devfn < max; devfn += PCI_FUNC_MAX) {
+ if (!pbus->devices[devfn]) {
+ break;
+ }
+ }
+ return devfn < max;
+}
+
static void pci_bus_class_init(ObjectClass *klass, void *data)
{
BusClass *k = BUS_CLASS(klass);
@@ -119,6 +140,7 @@ static void pci_bus_class_init(ObjectClass *klass, void
*data)
k->realize = pci_bus_realize;
k->unrealize = pci_bus_unrealize;
k->reset = pcibus_reset;
+ k->can_add_device = pci_can_add_device;
pbc->is_root = pcibus_is_root;
pbc->bus_num = pcibus_num;
diff --git a/include/hw/pci/pci_bus.h b/include/hw/pci/pci_bus.h
index 403fec6..02055d4 100644
--- a/include/hw/pci/pci_bus.h
+++ b/include/hw/pci/pci_bus.h
@@ -23,6 +23,7 @@ struct PCIBus {
PCIIOMMUFunc iommu_fn;
void *iommu_opaque;
uint8_t devfn_min;
+ uint8_t devfn_max;
pci_set_irq_fn set_irq;
pci_map_irq_fn map_irq;
pci_route_irq_fn route_intx_to_irq;
--
2.5.0
