[PATCH v8 03/29] hw/i386/pc_piix: Assign PIIX3's ISA interrupts before its realize()

[Bernhard Beschow <shentey@gmail.com>]

Unlike its PIIX4 counterpart, TYPE_PIIX3_DEVICE doesn't instantiate a PIC
itself. Instead, it relies on the board to do so. This means that the board
needs to wire the ISA IRQs to the PIIX3 device model. As long as the board
assigns the ISA IRQs after PIIX3's realize(), internal devices can't be wired in
pci_piix3_realize() since the qemu_irqs are still NULL. Fix that by assigning
the ISA interrupts before realize(). This will allow for embedding child devices
into the host device as already done for PIIX4.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>

---

Note that this avoids the "PIC proxy" of previous iterations of the PIIX
consolidation series. Assigning the IRQs before realize() has been agreed upon
at KVM forum 2023.
---
 hw/i386/pc_piix.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 6d2f5509e6..a003923788 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -265,6 +265,8 @@ static void pc_init1(MachineState *machine,
         PCIDevice *pci_dev;
 
         pci_dev = pci_new_multifunction(-1, TYPE_PIIX3_DEVICE);
+        piix3 = PIIX3_PCI_DEVICE(pci_dev);
+        piix3->pic = x86ms->gsi;
         pci_realize_and_unref(pci_dev, pci_bus, &error_fatal);
 
         if (xen_enabled()) {
@@ -281,8 +283,6 @@ static void pc_init1(MachineState *machine,
                          XEN_IOAPIC_NUM_PIRQS);
         }
 
-        piix3 = PIIX3_PCI_DEVICE(pci_dev);
-        piix3->pic = x86ms->gsi;
         piix3_devfn = piix3->dev.devfn;
         isa_bus = ISA_BUS(qdev_get_child_bus(DEVICE(piix3), "isa.0"));
         rtc_state = ISA_DEVICE(object_resolve_path_component(OBJECT(pci_dev),
-- 
2.42.0