hw/isa/piix4: Resolve global instance variable

Now that piix4_set_irq's opaque parameter references own PIIX4State,
piix4_dev becomes redundant.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20220217101924.15347-6-shentey@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

hw/isa/piix4.c

@@ -39,8 +39,6 @@
 #include "sysemu/runstate.h"
 #include "qom/object.h"
 
-PCIDevice *piix4_dev;
-
 struct PIIX4State {
     PCIDevice dev;
     qemu_irq cpu_intr;
@@ -58,16 +56,16 @@ static void piix4_set_irq(void *opaque, int irq_num, int level)
 {
     int i, pic_irq, pic_level;
     PIIX4State *s = opaque;
-    PCIBus *bus = pci_get_bus(piix4_dev);
+    PCIBus *bus = pci_get_bus(&s->dev);
 
     /* now we change the pic irq level according to the piix irq mappings */
     /* XXX: optimize */
-    pic_irq = piix4_dev->config[PIIX_PIRQCA + irq_num];
+    pic_irq = s->dev.config[PIIX_PIRQCA + irq_num];
     if (pic_irq < 16) {
         /* The pic level is the logical OR of all the PCI irqs mapped to it. */
         pic_level = 0;
         for (i = 0; i < 4; i++) {
-            if (pic_irq == piix4_dev->config[PIIX_PIRQCA + i]) {
+            if (pic_irq == s->dev.config[PIIX_PIRQCA + i]) {
                 pic_level |= pci_bus_get_irq_level(bus, i);
             }
         }
@@ -219,8 +217,6 @@ static void piix4_realize(PCIDevice *dev, Error **errp)
         return;
     }
     isa_init_irq(ISA_DEVICE(&s->rtc), &s->rtc.irq, RTC_ISA_IRQ);
-
-    piix4_dev = dev;
 }
 
 static void piix4_init(Object *obj)

include/hw/southbridge/piix.h

@@ -70,8 +70,6 @@ typedef struct PIIXState PIIX3State;
 DECLARE_INSTANCE_CHECKER(PIIX3State, PIIX3_PCI_DEVICE,
                          TYPE_PIIX3_PCI_DEVICE)
 
-extern PCIDevice *piix4_dev;
-
 PIIX3State *piix3_create(PCIBus *pci_bus, ISABus **isa_bus);
 
 DeviceState *piix4_create(PCIBus *pci_bus, ISABus **isa_bus, I2CBus **smbus);