pci: add accessor function to get irq levels

Introduce accessor function to know INTx levels.
It will be used later by q35.
Although piix_pci tracks the intx line levels, it can be eliminated
by this helper function.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

2 files changed, 8 insertions, 0 deletions

diff --git a/hw/pci.c b/hw/pci.c
index 6b577e1..3ee4871 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -126,6 +126,13 @@ static void pci_change_irq_level(PCIDevice *pci_dev, int irq_num, int change)
     bus->set_irq(bus->irq_opaque, irq_num, bus->irq_count[irq_num] != 0);
 }
 
+int pci_bus_get_irq_level(PCIBus *bus, int irq_num)
+{
+    assert(irq_num >= 0);
+    assert(irq_num < bus->nirq);
+    return !!bus->irq_count[irq_num];
+}
+
 /* Update interrupt status bit in config space on interrupt
  * state change. */
 static void pci_update_irq_status(PCIDevice *dev)
diff --git a/hw/pci.h b/hw/pci.h
index 52ee8c9..a5f875d 100644
--- a/hw/pci.h
+++ b/hw/pci.h
@@ -234,6 +234,7 @@ void pci_bus_new_inplace(PCIBus *bus, DeviceState *parent,
 PCIBus *pci_bus_new(DeviceState *parent, const char *name, uint8_t devfn_min);
 void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                   void *irq_opaque, int nirq);
+int pci_bus_get_irq_level(PCIBus *bus, int irq_num);
 void pci_bus_hotplug(PCIBus *bus, pci_hotplug_fn hotplug, DeviceState *dev);
 PCIBus *pci_register_bus(DeviceState *parent, const char *name,
                          pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,