diff --git a/hw/pci-host/apb.c b/hw/pci-host/apb.c
index f9badad..5000432 100644
--- a/hw/pci-host/apb.c
+++ b/hw/pci-host/apb.c
@@ -601,16 +601,35 @@ static uint64_t apb_pci_config_read(void *opaque, hwaddr addr,
 /* The APB host has an IRQ line for each IRQ line of each slot.  */
 static int pci_apb_map_irq(PCIDevice *pci_dev, int irq_num)
 {
-    return ((pci_dev->devfn & 0x18) >> 1) + irq_num;
+    /* Return the irq as swizzled by the PBM */
+    return irq_num;
 }
 
 static int pci_pbm_map_irq(PCIDevice *pci_dev, int irq_num)
 {
+    PBMPCIBridge *br = PBM_PCI_BRIDGE(pci_bridge_get_device(
+                           PCI_BUS(qdev_get_parent_bus(DEVICE(pci_dev)))));
+
     int bus_offset;
-    if (pci_dev->devfn & 1)
-        bus_offset = 16;
-    else
-        bus_offset = 0;
+    if (br->busA) {
+        bus_offset = 0x0;
+
+        /* The on-board devices have fixed (legacy) OBIO intnos */
+        switch (PCI_SLOT(pci_dev->devfn)) {
+        case 1:
+            /* Onboard NIC */
+            return 0x21;
+        case 3:
+            /* Onboard IDE */
+            return 0x20;
+
+        default:
+            /* Normal intno, fall through */
+            break;
+        }
+    } else {
+        bus_offset = 0x10;
+    }
     return (bus_offset + (PCI_SLOT(pci_dev->devfn) << 2) + irq_num) & 0x1f;
 }
 
@@ -692,7 +711,7 @@ PCIBus *pci_apb_init(hwaddr special_base,
     d = APB_DEVICE(dev);
     phb = PCI_HOST_BRIDGE(dev);
     phb->bus = pci_register_bus(DEVICE(phb), "pci",
-                                pci_apb_set_irq, pci_pbm_map_irq, d,
+                                pci_apb_set_irq, pci_apb_map_irq, d,
                                 &d->pci_mmio,
                                 get_system_io(),
                                 0, 32, TYPE_PCI_BUS);
@@ -726,14 +745,14 @@ PCIBus *pci_apb_init(hwaddr special_base,
     pci_dev = pci_create_multifunction(phb->bus, PCI_DEVFN(1, 0), true,
                                    TYPE_PBM_PCI_BRIDGE);
     br = PCI_BRIDGE(pci_dev);
-    pci_bridge_map_irq(br, "pciB", pci_apb_map_irq);
+    pci_bridge_map_irq(br, "pciB", pci_pbm_map_irq);
     qdev_init_nofail(&pci_dev->qdev);
     *busB = pci_bridge_get_sec_bus(br);
 
     pci_dev = pci_create_multifunction(phb->bus, PCI_DEVFN(1, 1), true,
                                    TYPE_PBM_PCI_BRIDGE);
     br = PCI_BRIDGE(pci_dev);
-    pci_bridge_map_irq(br, "pciA", pci_apb_map_irq);
+    pci_bridge_map_irq(br, "pciA", pci_pbm_map_irq);
     qdev_prop_set_bit(DEVICE(pci_dev), "busA", true);
     qdev_init_nofail(&pci_dev->qdev);
     *busA = pci_bridge_get_sec_bus(br);
diff --git a/hw/sparc64/sun4u.c b/hw/sparc64/sun4u.c
index 3bb3bf2..b8b96be 100644
--- a/hw/sparc64/sun4u.c
+++ b/hw/sparc64/sun4u.c
@@ -27,6 +27,7 @@
 #include "cpu.h"
 #include "hw/hw.h"
 #include "hw/pci/pci.h"
+#include "hw/pci/pci_bus.h"
 #include "hw/pci-host/apb.h"
 #include "hw/i386/pc.h"
 #include "hw/char/serial.h"
@@ -42,6 +43,7 @@
 #include "hw/nvram/fw_cfg.h"
 #include "hw/sysbus.h"
 #include "hw/ide.h"
+#include "hw/ide/pci.h"
 #include "hw/loader.h"
 #include "elf.h"
 #include "qemu/cutils.h"
@@ -448,10 +450,17 @@ static void sun4uv_init(MemoryRegion *address_space_mem,
     ivec_irqs = qemu_allocate_irqs(sparc64_cpu_set_ivec_irq, cpu, IVEC_MAX);
     pci_bus = pci_apb_init(APB_SPECIAL_BASE, APB_MEM_BASE, ivec_irqs, &pci_busA,
                            &pci_busB, &pbm_irqs);
-    pci_vga_init(pci_bus);
 
-    /* XXX Should be pci_busA */
-    ebus = pci_create_simple(pci_bus, -1, "ebus");
+    /* Only in-built Simba PBMs can exist on the root bus, slot 0 on busA is
+       reserved (leaving no slots free after on-board devices) leaving slots
+       0-3 are free on busB 4*/
+    pci_bus->slot_reserved_mask = 0xfffffffc;
+    pci_busA->slot_reserved_mask = 0xfffffff1;
+    pci_busB->slot_reserved_mask = 0xfffffff0;
+
+    ebus = pci_create_multifunction(pci_busA, PCI_DEVFN(1, 0), true, "ebus");
+    qdev_init_nofail(DEVICE(ebus));
+
     isa_bus = pci_ebus_init(ebus, pbm_irqs);
 
     i = 0;
@@ -464,14 +473,20 @@ static void sun4uv_init(MemoryRegion *address_space_mem,
     serial_hds_isa_init(isa_bus, i, MAX_SERIAL_PORTS);
     parallel_hds_isa_init(isa_bus, MAX_PARALLEL_PORTS);
 
-    pci_dev = pci_create(pci_bus, -1, "ne2k_pci");
+    pci_dev = pci_create_simple(pci_busA, PCI_DEVFN(2, 0), "VGA");
+
+    pci_dev = pci_create_multifunction(pci_busA, PCI_DEVFN(1, 1), true,
+                                       "ne2k_pci");
     dev = &pci_dev->qdev;
     qdev_set_nic_properties(dev, &nd_table[0]);
     qdev_init_nofail(dev);
 
     ide_drive_get(hd, ARRAY_SIZE(hd));
 
-    pci_cmd646_ide_init(pci_bus, hd, 1);
+    pci_dev = pci_create(pci_busA, PCI_DEVFN(3, 0), "cmd646-ide");
+    qdev_prop_set_uint32(&pci_dev->qdev, "secondary", 1);
+    qdev_init_nofail(&pci_dev->qdev);
+    pci_ide_create_devs(pci_dev, hd);
 
     isa_create_simple(isa_bus, "i8042");
 
