hw/pci/pci: Factor out pci_bus_map_irqs() from pci_bus_irqs()

pci_bus_irqs() coupled together the assignment of pci_set_irq_fn and
pci_map_irq_fn to a PCI bus. This coupling gets in the way when the
pci_map_irq_fn is board-specific while the pci_set_irq_fn is device-
specific.

For example, both of QEMU's PIIX south bridge models have different
pci_map_irq_fn implementations which are board-specific rather than
device-specific. These implementations should therefore reside in board
code. The pci_set_irq_fn's, however, should stay in the device models
because they access memory internal to the model.

Factoring out pci_bus_map_irqs() from pci_bus_irqs() allows the
assignments to be decoupled, resolving the problem described above.

Note also how pci_vpb_realize() which gets touched in this commit
assigns different pci_map_irq_fn's depending on the board.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230109172347.1830-5-shentey@gmail.com>
[PMD: Factor out in vfu_object_set_bus_irq()]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/hw/pci-host/versatile.c b/hw/pci-host/versatile.c
index 0d50ea4cc0..60d4e7cd92 100644
--- a/hw/pci-host/versatile.c
+++ b/hw/pci-host/versatile.c
@@ -422,7 +422,8 @@ static void pci_vpb_realize(DeviceState *dev, Error **errp)
         mapfn = pci_vpb_map_irq;
     }
 
-    pci_bus_irqs(&s->pci_bus, pci_vpb_set_irq, mapfn, s->irq, 4);
+    pci_bus_irqs(&s->pci_bus, pci_vpb_set_irq, s->irq, 4);
+    pci_bus_map_irqs(&s->pci_bus, mapfn);
 
     /* Our memory regions are:
      * 0 : our control registers