diff --git a/Makefile.objs b/Makefile.objs
index 285c6f3c15..c8b1bba593 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -140,6 +140,7 @@ trace-events-subdirs += hw/input
 trace-events-subdirs += hw/timer
 trace-events-subdirs += hw/dma
 trace-events-subdirs += hw/sparc
+trace-events-subdirs += hw/sparc64
 trace-events-subdirs += hw/sd
 trace-events-subdirs += hw/isa
 trace-events-subdirs += hw/mem
diff --git a/hw/dma/Makefile.objs b/hw/dma/Makefile.objs
index 087c8e6855..0b3a009b87 100644
--- a/hw/dma/Makefile.objs
+++ b/hw/dma/Makefile.objs
@@ -8,7 +8,6 @@ common-obj-$(CONFIG_XILINX_AXI) += xilinx_axidma.o
 common-obj-$(CONFIG_ZYNQ_DEVCFG) += xlnx-zynq-devcfg.o
 common-obj-$(CONFIG_ETRAXFS) += etraxfs_dma.o
 common-obj-$(CONFIG_STP2000) += sparc32_dma.o
-common-obj-$(CONFIG_SUN4M) += sun4m_iommu.o
 obj-$(CONFIG_XLNX_ZYNQMP) += xlnx_dpdma.o
 
 obj-$(CONFIG_OMAP) += omap_dma.o soc_dma.o
diff --git a/hw/dma/sparc32_dma.c b/hw/dma/sparc32_dma.c
index 01afb758b6..7b00a27de6 100644
--- a/hw/dma/sparc32_dma.c
+++ b/hw/dma/sparc32_dma.c
@@ -28,7 +28,7 @@
 #include "qemu/osdep.h"
 #include "hw/hw.h"
 #include "hw/sparc/sparc32_dma.h"
-#include "hw/sparc/sun4m.h"
+#include "hw/sparc/sun4m_iommu.h"
 #include "hw/sysbus.h"
 #include "sysemu/dma.h"
 #include "qapi/error.h"
diff --git a/hw/dma/trace-events b/hw/dma/trace-events
index 6b367f053b..22f53d0ff2 100644
--- a/hw/dma/trace-events
+++ b/hw/dma/trace-events
@@ -18,15 +18,5 @@ sparc32_dma_mem_writel(uint64_t addr, uint32_t old, uint32_t val) "write dmareg
 sparc32_dma_enable_raise(void) "Raise DMA enable"
 sparc32_dma_enable_lower(void) "Lower DMA enable"
 
-# hw/dma/sun4m_iommu.c
-sun4m_iommu_mem_readl(uint64_t addr, uint32_t ret) "read reg[0x%"PRIx64"] = 0x%x"
-sun4m_iommu_mem_writel(uint64_t addr, uint32_t val) "write reg[0x%"PRIx64"] = 0x%x"
-sun4m_iommu_mem_writel_ctrl(uint64_t iostart) "iostart = 0x%"PRIx64
-sun4m_iommu_mem_writel_tlbflush(uint32_t val) "tlb flush 0x%x"
-sun4m_iommu_mem_writel_pgflush(uint32_t val) "page flush 0x%x"
-sun4m_iommu_page_get_flags(uint64_t pa, uint64_t iopte, uint32_t ret) "get flags addr 0x%"PRIx64" => pte 0x%"PRIx64", *pte = 0x%x"
-sun4m_iommu_translate_pa(uint64_t addr, uint64_t pa, uint32_t iopte) "xlate dva 0x%"PRIx64" => pa 0x%"PRIx64" iopte = 0x%x"
-sun4m_iommu_bad_addr(uint64_t addr) "bad addr 0x%"PRIx64
-
 # hw/dma/i8257.c
 i8257_unregistered_dma(int nchan, int dma_pos, int dma_len) "unregistered DMA channel used nchan=%d dma_pos=%d dma_len=%d"
diff --git a/hw/intc/slavio_intctl.c b/hw/intc/slavio_intctl.c
index 84e0bee4a9..817e02617e 100644
--- a/hw/intc/slavio_intctl.c
+++ b/hw/intc/slavio_intctl.c
@@ -23,7 +23,6 @@
  */
 
 #include "qemu/osdep.h"
-#include "hw/sparc/sun4m.h"
 #include "monitor/monitor.h"
 #include "hw/sysbus.h"
 #include "hw/intc/intc.h"
diff --git a/hw/net/lance.c b/hw/net/lance.c
index 23929fd1e6..0028bc525d 100644
--- a/hw/net/lance.c
+++ b/hw/net/lance.c
@@ -40,7 +40,7 @@
 #include "net/net.h"
 #include "qemu/timer.h"
 #include "qemu/sockets.h"
-#include "hw/sparc/sun4m.h"
+#include "hw/sparc/sparc32_dma.h"
 #include "hw/net/lance.h"
 #include "trace.h"
 #include "sysemu/sysemu.h"
diff --git a/hw/pci-host/apb.c b/hw/pci-host/apb.c
index 64025cd8cc..3e796fb6fc 100644
--- a/hw/pci-host/apb.c
+++ b/hw/pci-host/apb.c
@@ -36,6 +36,7 @@
 #include "hw/pci-host/apb.h"
 #include "sysemu/sysemu.h"
 #include "exec/address-spaces.h"
+#include "qapi/error.h"
 #include "qemu/log.h"
 
 /* debug APB */
@@ -48,16 +49,6 @@ do { printf("APB: " fmt , ## __VA_ARGS__); } while (0)
 #define APB_DPRINTF(fmt, ...)
 #endif
 
-/* debug IOMMU */
-//#define DEBUG_IOMMU
-
-#ifdef DEBUG_IOMMU
-#define IOMMU_DPRINTF(fmt, ...) \
-do { printf("IOMMU: " fmt , ## __VA_ARGS__); } while (0)
-#else
-#define IOMMU_DPRINTF(fmt, ...)
-#endif
-
 /*
  * Chipset docs:
  * PBM: "UltraSPARC IIi User's Manual",
@@ -79,94 +70,8 @@ do { printf("IOMMU: " fmt , ## __VA_ARGS__); } while (0)
 #define RESET_WCMASK 0x98000000
 #define RESET_WMASK  0x60000000
 
-#define MAX_IVEC 0x40
 #define NO_IRQ_REQUEST (MAX_IVEC + 1)
 
-#define IOMMU_PAGE_SIZE_8K      (1ULL << 13)
-#define IOMMU_PAGE_MASK_8K      (~(IOMMU_PAGE_SIZE_8K - 1))
-#define IOMMU_PAGE_SIZE_64K     (1ULL << 16)
-#define IOMMU_PAGE_MASK_64K     (~(IOMMU_PAGE_SIZE_64K - 1))
-
-#define IOMMU_NREGS             3
-
-#define IOMMU_CTRL              0x0
-#define IOMMU_CTRL_TBW_SIZE     (1ULL << 2)
-#define IOMMU_CTRL_MMU_EN       (1ULL)
-
-#define IOMMU_CTRL_TSB_SHIFT    16
-
-#define IOMMU_BASE              0x8
-#define IOMMU_FLUSH             0x10
-
-#define IOMMU_TTE_DATA_V        (1ULL << 63)
-#define IOMMU_TTE_DATA_SIZE     (1ULL << 61)
-#define IOMMU_TTE_DATA_W        (1ULL << 1)
-
-#define IOMMU_TTE_PHYS_MASK_8K  0x1ffffffe000ULL
-#define IOMMU_TTE_PHYS_MASK_64K 0x1ffffff8000ULL
-
-#define IOMMU_TSB_8K_OFFSET_MASK_8M    0x00000000007fe000ULL
-#define IOMMU_TSB_8K_OFFSET_MASK_16M   0x0000000000ffe000ULL
-#define IOMMU_TSB_8K_OFFSET_MASK_32M   0x0000000001ffe000ULL
-#define IOMMU_TSB_8K_OFFSET_MASK_64M   0x0000000003ffe000ULL
-#define IOMMU_TSB_8K_OFFSET_MASK_128M  0x0000000007ffe000ULL
-#define IOMMU_TSB_8K_OFFSET_MASK_256M  0x000000000fffe000ULL
-#define IOMMU_TSB_8K_OFFSET_MASK_512M  0x000000001fffe000ULL
-#define IOMMU_TSB_8K_OFFSET_MASK_1G    0x000000003fffe000ULL
-
-#define IOMMU_TSB_64K_OFFSET_MASK_64M  0x0000000003ff0000ULL
-#define IOMMU_TSB_64K_OFFSET_MASK_128M 0x0000000007ff0000ULL
-#define IOMMU_TSB_64K_OFFSET_MASK_256M 0x000000000fff0000ULL
-#define IOMMU_TSB_64K_OFFSET_MASK_512M 0x000000001fff0000ULL
-#define IOMMU_TSB_64K_OFFSET_MASK_1G   0x000000003fff0000ULL
-#define IOMMU_TSB_64K_OFFSET_MASK_2G   0x000000007fff0000ULL
-
-typedef struct IOMMUState {
-    AddressSpace iommu_as;
-    IOMMUMemoryRegion iommu;
-
-    uint64_t regs[IOMMU_NREGS];
-} IOMMUState;
-
-#define TYPE_APB "pbm"
-
-#define APB_DEVICE(obj) \
-    OBJECT_CHECK(APBState, (obj), TYPE_APB)
-
-#define TYPE_APB_IOMMU_MEMORY_REGION "pbm-iommu-memory-region"
-
-typedef struct APBState {
-    PCIHostState parent_obj;
-
-    MemoryRegion apb_config;
-    MemoryRegion pci_config;
-    MemoryRegion pci_mmio;
-    MemoryRegion pci_ioport;
-    uint64_t pci_irq_in;
-    IOMMUState iommu;
-    uint32_t pci_control[16];
-    uint32_t pci_irq_map[8];
-    uint32_t pci_err_irq_map[4];
-    uint32_t obio_irq_map[32];
-    qemu_irq *pbm_irqs;
-    qemu_irq *ivec_irqs;
-    unsigned int irq_request;
-    uint32_t reset_control;
-    unsigned int nr_resets;
-} APBState;
-
-#define TYPE_PBM_PCI_BRIDGE "pbm-bridge"
-#define PBM_PCI_BRIDGE(obj) \
-    OBJECT_CHECK(PBMPCIBridge, (obj), TYPE_PBM_PCI_BRIDGE)
-
-typedef struct PBMPCIBridge {
-    /*< private >*/
-    PCIBridge parent_obj;
-
-    /* Is this busA with in-built devices (ebus)? */
-    bool busA;
-} PBMPCIBridge;
-
 static inline void pbm_set_request(APBState *s, unsigned int irq_num)
 {
     APB_DPRINTF("%s: request irq %d\n", __func__, irq_num);
@@ -221,216 +126,10 @@ static AddressSpace *pbm_pci_dma_iommu(PCIBus *bus, void *opaque, int devfn)
     return &is->iommu_as;
 }
 
-/* Called from RCU critical section */
-static IOMMUTLBEntry pbm_translate_iommu(IOMMUMemoryRegion *iommu, hwaddr addr,
-                                         IOMMUAccessFlags flag)
-{
-    IOMMUState *is = container_of(iommu, IOMMUState, iommu);
-    hwaddr baseaddr, offset;
-    uint64_t tte;
-    uint32_t tsbsize;
-    IOMMUTLBEntry ret = {
-        .target_as = &address_space_memory,
-        .iova = 0,
-        .translated_addr = 0,
-        .addr_mask = ~(hwaddr)0,
-        .perm = IOMMU_NONE,
-    };
-
-    if (!(is->regs[IOMMU_CTRL >> 3] & IOMMU_CTRL_MMU_EN)) {
-        /* IOMMU disabled, passthrough using standard 8K page */
-        ret.iova = addr & IOMMU_PAGE_MASK_8K;
-        ret.translated_addr = addr;
-        ret.addr_mask = IOMMU_PAGE_MASK_8K;
-        ret.perm = IOMMU_RW;
-
-        return ret;
-    }
-
-    baseaddr = is->regs[IOMMU_BASE >> 3];
-    tsbsize = (is->regs[IOMMU_CTRL >> 3] >> IOMMU_CTRL_TSB_SHIFT) & 0x7;
-
-    if (is->regs[IOMMU_CTRL >> 3] & IOMMU_CTRL_TBW_SIZE) {
-        /* 64K */
-        switch (tsbsize) {
-        case 0:
-            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_64M) >> 13;
-            break;
-        case 1:
-            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_128M) >> 13;
-            break;
-        case 2:
-            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_256M) >> 13;
-            break;
-        case 3:
-            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_512M) >> 13;
-            break;
-        case 4:
-            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_1G) >> 13;
-            break;
-        case 5:
-            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_2G) >> 13;
-            break;
-        default:
-            /* Not implemented, error */
-            return ret;
-        }
-    } else {
-        /* 8K */
-        switch (tsbsize) {
-        case 0:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_8M) >> 10;
-            break;
-        case 1:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_16M) >> 10;
-            break;
-        case 2:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_32M) >> 10;
-            break;
-        case 3:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_64M) >> 10;
-            break;
-        case 4:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_128M) >> 10;
-            break;
-        case 5:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_256M) >> 10;
-            break;
-        case 6:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_512M) >> 10;
-            break;
-        case 7:
-            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_1G) >> 10;
-            break;
-        }
-    }
-
-    tte = address_space_ldq_be(&address_space_memory, baseaddr + offset,
-                               MEMTXATTRS_UNSPECIFIED, NULL);
-
-    if (!(tte & IOMMU_TTE_DATA_V)) {
-        /* Invalid mapping */
-        return ret;
-    }
-
-    if (tte & IOMMU_TTE_DATA_W) {
-        /* Writeable */
-        ret.perm = IOMMU_RW;
-    } else {
-        ret.perm = IOMMU_RO;
-    }
-
-    /* Extract phys */
-    if (tte & IOMMU_TTE_DATA_SIZE) {
-        /* 64K */
-        ret.iova = addr & IOMMU_PAGE_MASK_64K;
-        ret.translated_addr = tte & IOMMU_TTE_PHYS_MASK_64K;
-        ret.addr_mask = (IOMMU_PAGE_SIZE_64K - 1);
-    } else {
-        /* 8K */
-        ret.iova = addr & IOMMU_PAGE_MASK_8K;
-        ret.translated_addr = tte & IOMMU_TTE_PHYS_MASK_8K;
-        ret.addr_mask = (IOMMU_PAGE_SIZE_8K - 1);
-    }
-
-    return ret;
-}
-
-static void iommu_config_write(void *opaque, hwaddr addr,
-                               uint64_t val, unsigned size)
-{
-    IOMMUState *is = opaque;
-
-    IOMMU_DPRINTF("IOMMU config write: 0x%" HWADDR_PRIx " val: %" PRIx64
-                  " size: %d\n", addr, val, size);
-
-    switch (addr) {
-    case IOMMU_CTRL:
-        if (size == 4) {
-            is->regs[IOMMU_CTRL >> 3] &= 0xffffffffULL;
-            is->regs[IOMMU_CTRL >> 3] |= val << 32;
-        } else {
-            is->regs[IOMMU_CTRL >> 3] = val;
-        }
-        break;
-    case IOMMU_CTRL + 0x4:
-        is->regs[IOMMU_CTRL >> 3] &= 0xffffffff00000000ULL;
-        is->regs[IOMMU_CTRL >> 3] |= val & 0xffffffffULL;
-        break;
-    case IOMMU_BASE:
-        if (size == 4) {
-            is->regs[IOMMU_BASE >> 3] &= 0xffffffffULL;
-            is->regs[IOMMU_BASE >> 3] |= val << 32;
-        } else {
-            is->regs[IOMMU_BASE >> 3] = val;
-        }
-        break;
-    case IOMMU_BASE + 0x4:
-        is->regs[IOMMU_BASE >> 3] &= 0xffffffff00000000ULL;
-        is->regs[IOMMU_BASE >> 3] |= val & 0xffffffffULL;
-        break;
-    case IOMMU_FLUSH:
-    case IOMMU_FLUSH + 0x4:
-        break;
-    default:
-        qemu_log_mask(LOG_UNIMP,
-                  "apb iommu: Unimplemented register write "
-                  "reg 0x%" HWADDR_PRIx " size 0x%x value 0x%" PRIx64 "\n",
-                  addr, size, val);
-        break;
-    }
-}
-
-static uint64_t iommu_config_read(void *opaque, hwaddr addr, unsigned size)
-{
-    IOMMUState *is = opaque;
-    uint64_t val;
-
-    switch (addr) {
-    case IOMMU_CTRL:
-        if (size == 4) {
-            val = is->regs[IOMMU_CTRL >> 3] >> 32;
-        } else {
-            val = is->regs[IOMMU_CTRL >> 3];
-        }
-        break;
-    case IOMMU_CTRL + 0x4:
-        val = is->regs[IOMMU_CTRL >> 3] & 0xffffffffULL;
-        break;
-    case IOMMU_BASE:
-        if (size == 4) {
-            val = is->regs[IOMMU_BASE >> 3] >> 32;
-        } else {
-            val = is->regs[IOMMU_BASE >> 3];
-        }
-        break;
-    case IOMMU_BASE + 0x4:
-        val = is->regs[IOMMU_BASE >> 3] & 0xffffffffULL;
-        break;
-    case IOMMU_FLUSH:
-    case IOMMU_FLUSH + 0x4:
-        val = 0;
-        break;
-    default:
-        qemu_log_mask(LOG_UNIMP,
-                      "apb iommu: Unimplemented register read "
-                      "reg 0x%" HWADDR_PRIx " size 0x%x\n",
-                      addr, size);
-        val = 0;
-        break;
-    }
-
-    IOMMU_DPRINTF("IOMMU config read: 0x%" HWADDR_PRIx " val: %" PRIx64
-                  " size: %d\n", addr, val, size);
-
-    return val;
-}
-
 static void apb_config_writel (void *opaque, hwaddr addr,
                                uint64_t val, unsigned size)
 {
     APBState *s = opaque;
-    IOMMUState *is = &s->iommu;
 
     APB_DPRINTF("%s: addr " TARGET_FMT_plx " val %" PRIx64 "\n", __func__, addr, val);
 
@@ -438,9 +137,6 @@ static void apb_config_writel (void *opaque, hwaddr addr,
     case 0x30 ... 0x4f: /* DMA error registers */
         /* XXX: not implemented yet */
         break;
-    case 0x200 ... 0x217: /* IOMMU */
-        iommu_config_write(is, (addr & 0x1f), val, size);
-        break;
     case 0xc00 ... 0xc3f: /* PCI interrupt control */
         if (addr & 4) {
             unsigned int ino = (addr & 0x3f) >> 3;
@@ -512,7 +208,6 @@ static uint64_t apb_config_readl (void *opaque,
                                   hwaddr addr, unsigned size)
 {
     APBState *s = opaque;
-    IOMMUState *is = &s->iommu;
     uint32_t val;
 
     switch (addr & 0xffff) {
@@ -520,9 +215,6 @@ static uint64_t apb_config_readl (void *opaque,
         val = 0;
         /* XXX: not implemented yet */
         break;
-    case 0x200 ... 0x217: /* IOMMU */
-        val = iommu_config_read(is, (addr & 0x1f), size);
-        break;
     case 0xc00 ... 0xc3f: /* PCI interrupt control */
         if (addr & 4) {
             val = s->pci_irq_map[(addr & 0x3f) >> 3];
@@ -603,32 +295,27 @@ static int pci_apb_map_irq(PCIDevice *pci_dev, int irq_num)
     return irq_num;
 }
 
-static int pci_pbm_map_irq(PCIDevice *pci_dev, int irq_num)
+static int pci_pbmA_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 (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;
+    /* The on-board devices have fixed (legacy) OBIO intnos */
+    switch (PCI_SLOT(pci_dev->devfn)) {
+    case 1:
+        /* Onboard NIC */
+        return OBIO_NIC_IRQ;
+    case 3:
+        /* Onboard IDE */
+        return OBIO_HDD_IRQ;
+    default:
+        /* Normal intno, fall through */
+        break;
     }
-    return (bus_offset + (PCI_SLOT(pci_dev->devfn) << 2) + irq_num) & 0x1f;
+
+    return ((PCI_SLOT(pci_dev->devfn) << 2) + irq_num) & 0x1f;
+}
+
+static int pci_pbmB_map_irq(PCIDevice *pci_dev, int irq_num)
+{
+    return (0x10 + (PCI_SLOT(pci_dev->devfn) << 2) + irq_num) & 0x1f;
 }
 
 static void pci_apb_set_irq(void *opaque, int irq_num, int level)
@@ -672,18 +359,11 @@ static void apb_pci_bridge_realize(PCIDevice *dev, Error **errp)
      *   the reset value should be zero unless the boot pin is tied high
      *   (which is true) and thus it should be PCI_COMMAND_MEMORY.
      */
-    uint16_t cmd = PCI_COMMAND_MEMORY;
     PBMPCIBridge *br = PBM_PCI_BRIDGE(dev);
 
     pci_bridge_initfn(dev, TYPE_PCI_BUS);
 
-    /* If initialising busA, ensure that we allow IO transactions so that
-       we get the early serial console until OpenBIOS configures the bridge */
-    if (br->busA) {
-        cmd |= PCI_COMMAND_IO;
-    }
-
-    pci_set_word(dev->config + PCI_COMMAND, cmd);
+    pci_set_word(dev->config + PCI_COMMAND, PCI_COMMAND_MEMORY);
     pci_set_word(dev->config + PCI_STATUS,
                  PCI_STATUS_FAST_BACK | PCI_STATUS_66MHZ |
                  PCI_STATUS_DEVSEL_MEDIUM);
@@ -697,78 +377,12 @@ static void apb_pci_bridge_realize(PCIDevice *dev, Error **errp)
     pci_bridge_update_mappings(PCI_BRIDGE(br));
 }
 
-PCIBus *pci_apb_init(hwaddr special_base,
-                     hwaddr mem_base,
-                     qemu_irq *ivec_irqs, PCIBus **busA, PCIBus **busB,
-                     qemu_irq **pbm_irqs)
-{
-    DeviceState *dev;
-    SysBusDevice *s;
-    PCIHostState *phb;
-    APBState *d;
-    IOMMUState *is;
-    PCIDevice *pci_dev;
-    PCIBridge *br;
-
-    /* Ultrasparc PBM main bus */
-    dev = qdev_create(NULL, TYPE_APB);
-    d = APB_DEVICE(dev);
-    phb = PCI_HOST_BRIDGE(dev);
-    phb->bus = pci_register_bus(DEVICE(phb), "pci",
-                                pci_apb_set_irq, pci_apb_map_irq, d,
-                                &d->pci_mmio,
-                                &d->pci_ioport,
-                                0, 32, TYPE_PCI_BUS);
-    qdev_init_nofail(dev);
-    s = SYS_BUS_DEVICE(dev);
-    /* apb_config */
-    sysbus_mmio_map(s, 0, special_base);
-    /* PCI configuration space */
-    sysbus_mmio_map(s, 1, special_base + 0x1000000ULL);
-    /* pci_ioport */
-    sysbus_mmio_map(s, 2, special_base + 0x2000000ULL);
-
-    memory_region_init(&d->pci_mmio, OBJECT(s), "pci-mmio", 0x100000000ULL);
-    memory_region_add_subregion(get_system_memory(), mem_base, &d->pci_mmio);
-
-    *pbm_irqs = d->pbm_irqs;
-    d->ivec_irqs = ivec_irqs;
-
-    pci_create_simple(phb->bus, 0, "pbm-pci");
-
-    /* APB IOMMU */
-    is = &d->iommu;
-    memset(is, 0, sizeof(IOMMUState));
-
-    memory_region_init_iommu(&is->iommu, sizeof(is->iommu),
-                             TYPE_APB_IOMMU_MEMORY_REGION, OBJECT(dev),
-                             "iommu-apb", UINT64_MAX);
-    address_space_init(&is->iommu_as, MEMORY_REGION(&is->iommu), "pbm-as");
-    pci_setup_iommu(phb->bus, pbm_pci_dma_iommu, is);
-
-    /* APB secondary busses */
-    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_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_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);
-
-    return phb->bus;
-}
-
 static void pci_pbm_reset(DeviceState *d)
 {
-    unsigned int i;
     APBState *s = APB_DEVICE(d);
+    PCIDevice *pci_dev;
+    unsigned int i;
+    uint16_t cmd;
 
     for (i = 0; i < 8; i++) {
         s->pci_irq_map[i] &= PBM_PCI_IMR_MASK;
@@ -784,6 +398,15 @@ static void pci_pbm_reset(DeviceState *d)
         /* Power on reset */
         s->reset_control = POR;
     }
+
+    /* As this is the busA PCI bridge which contains the on-board devices
+     * attached to the ebus, ensure that we initially allow IO transactions
+     * so that we get the early serial console until OpenBIOS can properly
+     * configure the PCI bridge itself */
+    pci_dev = PCI_DEVICE(s->bridgeA);
+    cmd = pci_get_word(pci_dev->config + PCI_COMMAND);
+    pci_set_word(pci_dev->config + PCI_COMMAND, cmd | PCI_COMMAND_IO);
+    pci_bridge_update_mappings(PCI_BRIDGE(pci_dev));
 }
 
 static const MemoryRegionOps pci_config_ops = {
@@ -792,12 +415,57 @@ static const MemoryRegionOps pci_config_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
 };
 
-static int pci_pbm_init_device(SysBusDevice *dev)
+static void pci_pbm_realize(DeviceState *dev, Error **errp)
 {
-    APBState *s;
+    APBState *s = APB_DEVICE(dev);
+    PCIHostState *phb = PCI_HOST_BRIDGE(dev);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(s);
+    PCIDevice *pci_dev;
+
+    /* apb_config */
+    sysbus_mmio_map(sbd, 0, s->special_base);
+    /* PCI configuration space */
+    sysbus_mmio_map(sbd, 1, s->special_base + 0x1000000ULL);
+    /* pci_ioport */
+    sysbus_mmio_map(sbd, 2, s->special_base + 0x2000000ULL);
+
+    memory_region_init(&s->pci_mmio, OBJECT(s), "pci-mmio", 0x100000000ULL);
+    memory_region_add_subregion(get_system_memory(), s->mem_base,
+                                &s->pci_mmio);
+
+    phb->bus = pci_register_bus(dev, "pci",
+                                pci_apb_set_irq, pci_apb_map_irq, s,
+                                &s->pci_mmio,
+                                &s->pci_ioport,
+                                0, 32, TYPE_PCI_BUS);
+
+    pci_create_simple(phb->bus, 0, "pbm-pci");
+
+    /* APB IOMMU */
+    memory_region_add_subregion_overlap(&s->apb_config, 0x200,
+                    sysbus_mmio_get_region(SYS_BUS_DEVICE(s->iommu), 0), 1);
+    pci_setup_iommu(phb->bus, pbm_pci_dma_iommu, s->iommu);
+
+    /* APB secondary busses */
+    pci_dev = pci_create_multifunction(phb->bus, PCI_DEVFN(1, 0), true,
+                                   TYPE_PBM_PCI_BRIDGE);
+    s->bridgeB = PCI_BRIDGE(pci_dev);
+    pci_bridge_map_irq(s->bridgeB, "pciB", pci_pbmB_map_irq);
+    qdev_init_nofail(&pci_dev->qdev);
+
+    pci_dev = pci_create_multifunction(phb->bus, PCI_DEVFN(1, 1), true,
+                                   TYPE_PBM_PCI_BRIDGE);
+    s->bridgeA = PCI_BRIDGE(pci_dev);
+    pci_bridge_map_irq(s->bridgeA, "pciA", pci_pbmA_map_irq);
+    qdev_init_nofail(&pci_dev->qdev);
+}
+
+static void pci_pbm_init(Object *obj)
+{
+    APBState *s = APB_DEVICE(obj);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
     unsigned int i;
 
-    s = APB_DEVICE(dev);
     for (i = 0; i < 8; i++) {
         s->pci_irq_map[i] = (0x1f << 6) | (i << 2);
     }
@@ -807,28 +475,33 @@ static int pci_pbm_init_device(SysBusDevice *dev)
     for (i = 0; i < 32; i++) {
         s->obio_irq_map[i] = ((0x1f << 6) | 0x20) + i;
     }
-    s->pbm_irqs = qemu_allocate_irqs(pci_apb_set_irq, s, MAX_IVEC);
+    qdev_init_gpio_in_named(DEVICE(s), pci_apb_set_irq, "pbm-irq", MAX_IVEC);
+    qdev_init_gpio_out_named(DEVICE(s), s->ivec_irqs, "ivec-irq", MAX_IVEC);
     s->irq_request = NO_IRQ_REQUEST;
     s->pci_irq_in = 0ULL;
 
+    /* IOMMU */
+    object_property_add_link(obj, "iommu", TYPE_SUN4U_IOMMU,
+                             (Object **) &s->iommu,
+                             qdev_prop_allow_set_link_before_realize,
+                             0, NULL);
+
     /* apb_config */
     memory_region_init_io(&s->apb_config, OBJECT(s), &apb_config_ops, s,
                           "apb-config", 0x10000);
     /* at region 0 */
-    sysbus_init_mmio(dev, &s->apb_config);
+    sysbus_init_mmio(sbd, &s->apb_config);
 
     memory_region_init_io(&s->pci_config, OBJECT(s), &pci_config_ops, s,
                           "apb-pci-config", 0x1000000);
     /* at region 1 */
-    sysbus_init_mmio(dev, &s->pci_config);
+    sysbus_init_mmio(sbd, &s->pci_config);
 
     /* pci_ioport */
     memory_region_init(&s->pci_ioport, OBJECT(s), "apb-pci-ioport", 0x1000000);
 
     /* at region 2 */
-    sysbus_init_mmio(dev, &s->pci_ioport);
-
-    return 0;
+    sysbus_init_mmio(sbd, &s->pci_ioport);
 }
 
 static void pbm_pci_host_realize(PCIDevice *d, Error **errp)
@@ -867,28 +540,30 @@ static const TypeInfo pbm_pci_host_info = {
     },
 };
 
+static Property pbm_pci_host_properties[] = {
+    DEFINE_PROP_UINT64("special-base", APBState, special_base, 0),
+    DEFINE_PROP_UINT64("mem-base", APBState, mem_base, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
 static void pbm_host_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
-    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 
-    k->init = pci_pbm_init_device;
-    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
+    dc->realize = pci_pbm_realize;
     dc->reset = pci_pbm_reset;
+    dc->props = pbm_pci_host_properties;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo pbm_host_info = {
     .name          = TYPE_APB,
     .parent        = TYPE_PCI_HOST_BRIDGE,
     .instance_size = sizeof(APBState),
+    .instance_init = pci_pbm_init,
     .class_init    = pbm_host_class_init,
 };
 
-static Property pbm_pci_properties[] = {
-    DEFINE_PROP_BOOL("busA", PBMPCIBridge, busA, false),
-    DEFINE_PROP_END_OF_LIST(),
-};
-
 static void pbm_pci_bridge_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -904,7 +579,6 @@ static void pbm_pci_bridge_class_init(ObjectClass *klass, void *data)
     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
     dc->reset = pci_bridge_reset;
     dc->vmsd = &vmstate_pci_device;
-    dc->props = pbm_pci_properties;
 }
 
 static const TypeInfo pbm_pci_bridge_info = {
@@ -918,25 +592,11 @@ static const TypeInfo pbm_pci_bridge_info = {
     },
 };
 
-static void pbm_iommu_memory_region_class_init(ObjectClass *klass, void *data)
-{
-    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_CLASS(klass);
-
-    imrc->translate = pbm_translate_iommu;
-}
-
-static const TypeInfo pbm_iommu_memory_region_info = {
-    .parent = TYPE_IOMMU_MEMORY_REGION,
-    .name = TYPE_APB_IOMMU_MEMORY_REGION,
-    .class_init = pbm_iommu_memory_region_class_init,
-};
-
 static void pbm_register_types(void)
 {
     type_register_static(&pbm_host_info);
     type_register_static(&pbm_pci_host_info);
     type_register_static(&pbm_pci_bridge_info);
-    type_register_static(&pbm_iommu_memory_region_info);
 }
 
 type_init(pbm_register_types)
diff --git a/hw/sparc/Makefile.objs b/hw/sparc/Makefile.objs
index c987b5b5df..e2d0828c39 100644
--- a/hw/sparc/Makefile.objs
+++ b/hw/sparc/Makefile.objs
@@ -1 +1 @@
-obj-y += sun4m.o leon3.o
+obj-y += sun4m_iommu.o sun4m.o leon3.o
diff --git a/hw/sparc/sun4m.c b/hw/sparc/sun4m.c
index e71648404c..dd0038095b 100644
--- a/hw/sparc/sun4m.c
+++ b/hw/sparc/sun4m.c
@@ -28,7 +28,7 @@
 #include "hw/sysbus.h"
 #include "qemu/error-report.h"
 #include "qemu/timer.h"
-#include "hw/sparc/sun4m.h"
+#include "hw/sparc/sun4m_iommu.h"
 #include "hw/timer/m48t59.h"
 #include "hw/sparc/sparc32_dma.h"
 #include "hw/block/fdc.h"
diff --git a/hw/dma/sun4m_iommu.c b/hw/sparc/sun4m_iommu.c
similarity index 98%
rename from hw/dma/sun4m_iommu.c
rename to hw/sparc/sun4m_iommu.c
index 30a05e8823..b677601fc6 100644
--- a/hw/dma/sun4m_iommu.c
+++ b/hw/sparc/sun4m_iommu.c
@@ -23,7 +23,7 @@
  */
 
 #include "qemu/osdep.h"
-#include "hw/sparc/sun4m.h"
+#include "hw/sparc/sun4m_iommu.h"
 #include "hw/sysbus.h"
 #include "exec/address-spaces.h"
 #include "trace.h"
@@ -125,7 +125,7 @@
 
 #define IOMMU_PAGE_SHIFT    12
 #define IOMMU_PAGE_SIZE     (1 << IOMMU_PAGE_SHIFT)
-#define IOMMU_PAGE_MASK     ~(IOMMU_PAGE_SIZE - 1)
+#define IOMMU_PAGE_MASK     (~(IOMMU_PAGE_SIZE - 1))
 
 static uint64_t iommu_mem_read(void *opaque, hwaddr addr,
                                unsigned size)
@@ -218,8 +218,8 @@ static void iommu_mem_write(void *opaque, hwaddr addr,
         s->regs[saddr] = val & IOMMU_SBCFG_MASK;
         break;
     case IOMMU_ARBEN:
-        // XXX implement SBus probing: fault when reading unmapped
-        // addresses, fault cause and address stored to MMU/IOMMU
+        /* XXX implement SBus probing: fault when reading unmapped
+           addresses, fault cause and address stored to MMU/IOMMU */
         s->regs[saddr] = (val & IOMMU_ARBEN_MASK) | IOMMU_MID;
         break;
     case IOMMU_MASK_ID:
@@ -272,8 +272,9 @@ static void iommu_bad_addr(IOMMUState *s, hwaddr addr,
     trace_sun4m_iommu_bad_addr(addr);
     s->regs[IOMMU_AFSR] = IOMMU_AFSR_ERR | IOMMU_AFSR_LE | IOMMU_AFSR_RESV |
         IOMMU_AFSR_FAV;
-    if (!is_write)
+    if (!is_write) {
         s->regs[IOMMU_AFSR] |= IOMMU_AFSR_RD;
+    }
     s->regs[IOMMU_AFAR] = addr;
     qemu_irq_raise(s->irq);
 }
@@ -322,7 +323,7 @@ static IOMMUTLBEntry sun4m_translate_iommu(IOMMUMemoryRegion *iommu,
 }
 
 static const VMStateDescription vmstate_iommu = {
-    .name ="iommu",
+    .name = "iommu",
     .version_id = 2,
     .minimum_version_id = 2,
     .fields = (VMStateField[]) {
diff --git a/hw/sparc/trace-events b/hw/sparc/trace-events
index efd765cbe6..6e7259f8f8 100644
--- a/hw/sparc/trace-events
+++ b/hw/sparc/trace-events
@@ -6,6 +6,16 @@ sun4m_cpu_reset_interrupt(unsigned int level) "Reset CPU IRQ %d"
 sun4m_cpu_set_irq_raise(int level) "Raise CPU IRQ %d"
 sun4m_cpu_set_irq_lower(int level) "Lower CPU IRQ %d"
 
+# hw/sparc/sun4m_iommu.c
+sun4m_iommu_mem_readl(uint64_t addr, uint32_t ret) "read reg[0x%"PRIx64"] = 0x%x"
+sun4m_iommu_mem_writel(uint64_t addr, uint32_t val) "write reg[0x%"PRIx64"] = 0x%x"
+sun4m_iommu_mem_writel_ctrl(uint64_t iostart) "iostart = 0x%"PRIx64
+sun4m_iommu_mem_writel_tlbflush(uint32_t val) "tlb flush 0x%x"
+sun4m_iommu_mem_writel_pgflush(uint32_t val) "page flush 0x%x"
+sun4m_iommu_page_get_flags(uint64_t pa, uint64_t iopte, uint32_t ret) "get flags addr 0x%"PRIx64" => pte 0x%"PRIx64", *pte = 0x%x"
+sun4m_iommu_translate_pa(uint64_t addr, uint64_t pa, uint32_t iopte) "xlate dva 0x%"PRIx64" => pa 0x%"PRIx64" iopte = 0x%x"
+sun4m_iommu_bad_addr(uint64_t addr) "bad addr 0x%"PRIx64
+
 # hw/sparc/leon3.c
 leon3_set_irq(int intno) "Set CPU IRQ %d"
 leon3_reset_irq(int intno) "Reset CPU IRQ %d"
diff --git a/hw/sparc64/Makefile.objs b/hw/sparc64/Makefile.objs
index cf9de21133..117e0ff27d 100644
--- a/hw/sparc64/Makefile.objs
+++ b/hw/sparc64/Makefile.objs
@@ -1,3 +1,4 @@
 obj-y += sparc64.o
+obj-y += sun4u_iommu.o
 obj-y += sun4u.o
 obj-y += niagara.o
\ No newline at end of file
diff --git a/hw/sparc64/sparc64.c b/hw/sparc64/sparc64.c
index 9453e2c390..95a06f00b2 100644
--- a/hw/sparc64/sparc64.c
+++ b/hw/sparc64/sparc64.c
@@ -350,6 +350,8 @@ SPARCCPU *sparc64_cpu_devinit(const char *cpu_type, uint64_t prom_addr)
     uint32_t hstick_frequency = 100 * 1000000;
 
     cpu = SPARC_CPU(cpu_create(cpu_type));
+    qdev_init_gpio_in_named(DEVICE(cpu), sparc64_cpu_set_ivec_irq,
+                            "ivec-irq", IVEC_MAX);
     env = &cpu->env;
 
     env->tick = cpu_timer_create("tick", cpu, tick_irq,
diff --git a/hw/sparc64/sun4u.c b/hw/sparc64/sun4u.c
index 1672f256e7..ec45ec2801 100644
--- a/hw/sparc64/sun4u.c
+++ b/hw/sparc64/sun4u.c
@@ -27,7 +27,9 @@
 #include "cpu.h"
 #include "hw/hw.h"
 #include "hw/pci/pci.h"
+#include "hw/pci/pci_bridge.h"
 #include "hw/pci/pci_bus.h"
+#include "hw/pci/pci_host.h"
 #include "hw/pci-host/apb.h"
 #include "hw/i386/pc.h"
 #include "hw/char/serial.h"
@@ -46,17 +48,9 @@
 #include "hw/ide/pci.h"
 #include "hw/loader.h"
 #include "elf.h"
+#include "trace.h"
 #include "qemu/cutils.h"
 
-//#define DEBUG_EBUS
-
-#ifdef DEBUG_EBUS
-#define EBUS_DPRINTF(fmt, ...)                                  \
-    do { printf("EBUS: " fmt , ## __VA_ARGS__); } while (0)
-#else
-#define EBUS_DPRINTF(fmt, ...)
-#endif
-
 #define KERNEL_LOAD_ADDR     0x00404000
 #define CMDLINE_ADDR         0x003ff000
 #define PROM_SIZE_MAX        (4 * 1024 * 1024)
@@ -81,11 +75,19 @@ struct hwdef {
 };
 
 typedef struct EbusState {
-    PCIDevice pci_dev;
+    /*< private >*/
+    PCIDevice parent_obj;
+
+    ISABus *isa_bus;
+    qemu_irq isa_bus_irqs[ISA_NUM_IRQS];
+    uint64_t console_serial_base;
     MemoryRegion bar0;
     MemoryRegion bar1;
 } EbusState;
 
+#define TYPE_EBUS "ebus"
+#define EBUS(obj) OBJECT_CHECK(EbusState, (obj), TYPE_EBUS)
+
 void DMA_init(ISABus *bus, int high_page_enable)
 {
 }
@@ -203,48 +205,72 @@ typedef struct ResetData {
     uint64_t prom_addr;
 } ResetData;
 
-static void isa_irq_handler(void *opaque, int n, int level)
+static void ebus_isa_irq_handler(void *opaque, int n, int level)
 {
-    static const int isa_irq_to_ivec[16] = {
-        [1] = 0x29, /* keyboard */
-        [4] = 0x2b, /* serial */
-        [6] = 0x27, /* floppy */
-        [7] = 0x22, /* parallel */
-        [12] = 0x2a, /* mouse */
-    };
-    qemu_irq *irqs = opaque;
-    int ivec;
+    EbusState *s = EBUS(opaque);
+    qemu_irq irq = s->isa_bus_irqs[n];
 
-    assert(n < ARRAY_SIZE(isa_irq_to_ivec));
-    ivec = isa_irq_to_ivec[n];
-    EBUS_DPRINTF("Set ISA IRQ %d level %d -> ivec 0x%x\n", n, level, ivec);
-    if (ivec) {
-        qemu_set_irq(irqs[ivec], level);
+    /* Pass ISA bus IRQs onto their gpio equivalent */
+    trace_ebus_isa_irq_handler(n, level);
+    if (irq) {
+        qemu_set_irq(irq, level);
     }
 }
 
 /* EBUS (Eight bit bus) bridge */
-static ISABus *
-pci_ebus_init(PCIDevice *pci_dev, qemu_irq *irqs)
+static void ebus_realize(PCIDevice *pci_dev, Error **errp)
 {
+    EbusState *s = EBUS(pci_dev);
+    DeviceState *dev;
     qemu_irq *isa_irq;
-    ISABus *isa_bus;
+    DriveInfo *fd[MAX_FD];
+    int i;
 
-    isa_bus = ISA_BUS(qdev_get_child_bus(DEVICE(pci_dev), "isa.0"));
-    isa_irq = qemu_allocate_irqs(isa_irq_handler, irqs, 16);
-    isa_bus_irqs(isa_bus, isa_irq);
-    return isa_bus;
-}
-
-static void pci_ebus_realize(PCIDevice *pci_dev, Error **errp)
-{
-    EbusState *s = DO_UPCAST(EbusState, pci_dev, pci_dev);
-
-    if (!isa_bus_new(DEVICE(pci_dev), get_system_memory(),
-                     pci_address_space_io(pci_dev), errp)) {
+    s->isa_bus = isa_bus_new(DEVICE(pci_dev), get_system_memory(),
+                             pci_address_space_io(pci_dev), errp);
+    if (!s->isa_bus) {
+        error_setg(errp, "unable to instantiate EBUS ISA bus");
         return;
     }
 
+    /* ISA bus */
+    isa_irq = qemu_allocate_irqs(ebus_isa_irq_handler, s, ISA_NUM_IRQS);
+    isa_bus_irqs(s->isa_bus, isa_irq);
+    qdev_init_gpio_out_named(DEVICE(s), s->isa_bus_irqs, "isa-irq",
+                             ISA_NUM_IRQS);
+
+    /* Serial ports */
+    i = 0;
+    if (s->console_serial_base) {
+        serial_mm_init(pci_address_space(pci_dev), s->console_serial_base,
+                       0, NULL, 115200, serial_hds[i], DEVICE_BIG_ENDIAN);
+        i++;
+    }
+    serial_hds_isa_init(s->isa_bus, i, MAX_SERIAL_PORTS);
+
+    /* Parallel ports */
+    parallel_hds_isa_init(s->isa_bus, MAX_PARALLEL_PORTS);
+
+    /* Keyboard */
+    isa_create_simple(s->isa_bus, "i8042");
+
+    /* Floppy */
+    for (i = 0; i < MAX_FD; i++) {
+        fd[i] = drive_get(IF_FLOPPY, 0, i);
+    }
+    dev = DEVICE(isa_create(s->isa_bus, TYPE_ISA_FDC));
+    if (fd[0]) {
+        qdev_prop_set_drive(dev, "driveA", blk_by_legacy_dinfo(fd[0]),
+                            &error_abort);
+    }
+    if (fd[1]) {
+        qdev_prop_set_drive(dev, "driveB", blk_by_legacy_dinfo(fd[1]),
+                            &error_abort);
+    }
+    qdev_prop_set_uint32(dev, "dma", -1);
+    qdev_init_nofail(dev);
+
+    /* PCI */
     pci_dev->config[0x04] = 0x06; // command = bus master, pci mem
     pci_dev->config[0x05] = 0x00;
     pci_dev->config[0x06] = 0xa0; // status = fast back-to-back, 66MHz, no error
@@ -260,22 +286,30 @@ static void pci_ebus_realize(PCIDevice *pci_dev, Error **errp)
     pci_register_bar(pci_dev, 1, PCI_BASE_ADDRESS_SPACE_IO, &s->bar1);
 }
 
+static Property ebus_properties[] = {
+    DEFINE_PROP_UINT64("console-serial-base", EbusState,
+                       console_serial_base, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
 static void ebus_class_init(ObjectClass *klass, void *data)
 {
     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
-    k->realize = pci_ebus_realize;
+    k->realize = ebus_realize;
     k->vendor_id = PCI_VENDOR_ID_SUN;
     k->device_id = PCI_DEVICE_ID_SUN_EBUS;
     k->revision = 0x01;
     k->class_id = PCI_CLASS_BRIDGE_OTHER;
+    dc->props = ebus_properties;
 }
 
 static const TypeInfo ebus_info = {
-    .name          = "ebus",
+    .name          = TYPE_EBUS,
     .parent        = TYPE_PCI_DEVICE,
-    .instance_size = sizeof(EbusState),
     .class_init    = ebus_class_init,
+    .instance_size = sizeof(EbusState),
     .interfaces = (InterfaceInfo[]) {
         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
         { },
@@ -431,14 +465,12 @@ static void sun4uv_init(MemoryRegion *address_space_mem,
     Nvram *nvram;
     unsigned int i;
     uint64_t initrd_addr, initrd_size, kernel_addr, kernel_size, kernel_entry;
+    APBState *apb;
     PCIBus *pci_bus, *pci_busA, *pci_busB;
     PCIDevice *ebus, *pci_dev;
-    ISABus *isa_bus;
     SysBusDevice *s;
-    qemu_irq *ivec_irqs, *pbm_irqs;
     DriveInfo *hd[MAX_IDE_BUS * MAX_IDE_DEVS];
-    DriveInfo *fd[MAX_FD];
-    DeviceState *dev;
+    DeviceState *iommu, *dev;
     FWCfgState *fw_cfg;
     NICInfo *nd;
     MACAddr macaddr;
@@ -447,14 +479,31 @@ static void sun4uv_init(MemoryRegion *address_space_mem,
     /* init CPUs */
     cpu = sparc64_cpu_devinit(machine->cpu_type, hwdef->prom_addr);
 
+    /* IOMMU */
+    iommu = qdev_create(NULL, TYPE_SUN4U_IOMMU);
+    qdev_init_nofail(iommu);
+
     /* set up devices */
     ram_init(0, machine->ram_size);
 
     prom_init(hwdef->prom_addr, bios_name);
 
-    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);
+    /* Init APB (PCI host bridge) */
+    apb = APB_DEVICE(qdev_create(NULL, TYPE_APB));
+    qdev_prop_set_uint64(DEVICE(apb), "special-base", APB_SPECIAL_BASE);
+    qdev_prop_set_uint64(DEVICE(apb), "mem-base", APB_MEM_BASE);
+    object_property_set_link(OBJECT(apb), OBJECT(iommu), "iommu", &error_abort);
+    qdev_init_nofail(DEVICE(apb));
+
+    /* Wire up PCI interrupts to CPU */
+    for (i = 0; i < IVEC_MAX; i++) {
+        qdev_connect_gpio_out_named(DEVICE(apb), "ivec-irq", i,
+            qdev_get_gpio_in_named(DEVICE(cpu), "ivec-irq", i));
+    }
+
+    pci_bus = PCI_HOST_BRIDGE(apb)->bus;
+    pci_busA = pci_bridge_get_sec_bus(apb->bridgeA);
+    pci_busB = pci_bridge_get_sec_bus(apb->bridgeB);
 
     /* 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) however slots
@@ -463,20 +512,22 @@ static void sun4uv_init(MemoryRegion *address_space_mem,
     pci_busA->slot_reserved_mask = 0xfffffff1;
     pci_busB->slot_reserved_mask = 0xfffffff0;
 
-    ebus = pci_create_multifunction(pci_busA, PCI_DEVFN(1, 0), true, "ebus");
+    ebus = pci_create_multifunction(pci_busA, PCI_DEVFN(1, 0), true, TYPE_EBUS);
+    qdev_prop_set_uint64(DEVICE(ebus), "console-serial-base",
+                         hwdef->console_serial_base);
     qdev_init_nofail(DEVICE(ebus));
 
-    isa_bus = pci_ebus_init(ebus, pbm_irqs);
-
-    i = 0;
-    if (hwdef->console_serial_base) {
-        serial_mm_init(address_space_mem, hwdef->console_serial_base, 0,
-                       NULL, 115200, serial_hds[i], DEVICE_BIG_ENDIAN);
-        i++;
-    }
-
-    serial_hds_isa_init(isa_bus, i, MAX_SERIAL_PORTS);
-    parallel_hds_isa_init(isa_bus, MAX_PARALLEL_PORTS);
+    /* Wire up "well-known" ISA IRQs to APB legacy obio IRQs */
+    qdev_connect_gpio_out_named(DEVICE(ebus), "isa-irq", 7,
+        qdev_get_gpio_in_named(DEVICE(apb), "pbm-irq", OBIO_LPT_IRQ));
+    qdev_connect_gpio_out_named(DEVICE(ebus), "isa-irq", 6,
+        qdev_get_gpio_in_named(DEVICE(apb), "pbm-irq", OBIO_FDD_IRQ));
+    qdev_connect_gpio_out_named(DEVICE(ebus), "isa-irq", 1,
+        qdev_get_gpio_in_named(DEVICE(apb), "pbm-irq", OBIO_KBD_IRQ));
+    qdev_connect_gpio_out_named(DEVICE(ebus), "isa-irq", 12,
+        qdev_get_gpio_in_named(DEVICE(apb), "pbm-irq", OBIO_MSE_IRQ));
+    qdev_connect_gpio_out_named(DEVICE(ebus), "isa-irq", 4,
+        qdev_get_gpio_in_named(DEVICE(apb), "pbm-irq", OBIO_SER_IRQ));
 
     pci_dev = pci_create_simple(pci_busA, PCI_DEVFN(2, 0), "VGA");
 
@@ -516,24 +567,6 @@ static void sun4uv_init(MemoryRegion *address_space_mem,
     qdev_init_nofail(&pci_dev->qdev);
     pci_ide_create_devs(pci_dev, hd);
 
-    isa_create_simple(isa_bus, "i8042");
-
-    /* Floppy */
-    for(i = 0; i < MAX_FD; i++) {
-        fd[i] = drive_get(IF_FLOPPY, 0, i);
-    }
-    dev = DEVICE(isa_create(isa_bus, TYPE_ISA_FDC));
-    if (fd[0]) {
-        qdev_prop_set_drive(dev, "driveA", blk_by_legacy_dinfo(fd[0]),
-                            &error_abort);
-    }
-    if (fd[1]) {
-        qdev_prop_set_drive(dev, "driveB", blk_by_legacy_dinfo(fd[1]),
-                            &error_abort);
-    }
-    qdev_prop_set_uint32(dev, "dma", -1);
-    qdev_init_nofail(dev);
-
     /* Map NVRAM into I/O (ebus) space */
     nvram = m48t59_init(NULL, 0, 0, NVRAM_SIZE, 1968, 59);
     s = SYS_BUS_DEVICE(nvram);
diff --git a/hw/sparc64/sun4u_iommu.c b/hw/sparc64/sun4u_iommu.c
new file mode 100644
index 0000000000..4cf8e69be9
--- /dev/null
+++ b/hw/sparc64/sun4u_iommu.c
@@ -0,0 +1,342 @@
+/*
+ * QEMU sun4u IOMMU emulation
+ *
+ * Copyright (c) 2006 Fabrice Bellard
+ * Copyright (c) 2012,2013 Artyom Tarasenko
+ * Copyright (c) 2017 Mark Cave-Ayland
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/sysbus.h"
+#include "hw/sparc/sun4u_iommu.h"
+#include "exec/address-spaces.h"
+#include "qapi/error.h"
+#include "qemu/log.h"
+#include "trace.h"
+
+
+#define IOMMU_PAGE_SIZE_8K      (1ULL << 13)
+#define IOMMU_PAGE_MASK_8K      (~(IOMMU_PAGE_SIZE_8K - 1))
+#define IOMMU_PAGE_SIZE_64K     (1ULL << 16)
+#define IOMMU_PAGE_MASK_64K     (~(IOMMU_PAGE_SIZE_64K - 1))
+
+#define IOMMU_CTRL              0x0
+#define IOMMU_CTRL_TBW_SIZE     (1ULL << 2)
+#define IOMMU_CTRL_MMU_EN       (1ULL)
+
+#define IOMMU_CTRL_TSB_SHIFT    16
+
+#define IOMMU_BASE              0x8
+#define IOMMU_FLUSH             0x10
+
+#define IOMMU_TTE_DATA_V        (1ULL << 63)
+#define IOMMU_TTE_DATA_SIZE     (1ULL << 61)
+#define IOMMU_TTE_DATA_W        (1ULL << 1)
+
+#define IOMMU_TTE_PHYS_MASK_8K  0x1ffffffe000ULL
+#define IOMMU_TTE_PHYS_MASK_64K 0x1ffffff8000ULL
+
+#define IOMMU_TSB_8K_OFFSET_MASK_8M    0x00000000007fe000ULL
+#define IOMMU_TSB_8K_OFFSET_MASK_16M   0x0000000000ffe000ULL
+#define IOMMU_TSB_8K_OFFSET_MASK_32M   0x0000000001ffe000ULL
+#define IOMMU_TSB_8K_OFFSET_MASK_64M   0x0000000003ffe000ULL
+#define IOMMU_TSB_8K_OFFSET_MASK_128M  0x0000000007ffe000ULL
+#define IOMMU_TSB_8K_OFFSET_MASK_256M  0x000000000fffe000ULL
+#define IOMMU_TSB_8K_OFFSET_MASK_512M  0x000000001fffe000ULL
+#define IOMMU_TSB_8K_OFFSET_MASK_1G    0x000000003fffe000ULL
+
+#define IOMMU_TSB_64K_OFFSET_MASK_64M  0x0000000003ff0000ULL
+#define IOMMU_TSB_64K_OFFSET_MASK_128M 0x0000000007ff0000ULL
+#define IOMMU_TSB_64K_OFFSET_MASK_256M 0x000000000fff0000ULL
+#define IOMMU_TSB_64K_OFFSET_MASK_512M 0x000000001fff0000ULL
+#define IOMMU_TSB_64K_OFFSET_MASK_1G   0x000000003fff0000ULL
+#define IOMMU_TSB_64K_OFFSET_MASK_2G   0x000000007fff0000ULL
+
+
+/* Called from RCU critical section */
+static IOMMUTLBEntry sun4u_translate_iommu(IOMMUMemoryRegion *iommu,
+                                           hwaddr addr,
+                                           IOMMUAccessFlags flag)
+{
+    IOMMUState *is = container_of(iommu, IOMMUState, iommu);
+    hwaddr baseaddr, offset;
+    uint64_t tte;
+    uint32_t tsbsize;
+    IOMMUTLBEntry ret = {
+        .target_as = &address_space_memory,
+        .iova = 0,
+        .translated_addr = 0,
+        .addr_mask = ~(hwaddr)0,
+        .perm = IOMMU_NONE,
+    };
+
+    if (!(is->regs[IOMMU_CTRL >> 3] & IOMMU_CTRL_MMU_EN)) {
+        /* IOMMU disabled, passthrough using standard 8K page */
+        ret.iova = addr & IOMMU_PAGE_MASK_8K;
+        ret.translated_addr = addr;
+        ret.addr_mask = IOMMU_PAGE_MASK_8K;
+        ret.perm = IOMMU_RW;
+
+        return ret;
+    }
+
+    baseaddr = is->regs[IOMMU_BASE >> 3];
+    tsbsize = (is->regs[IOMMU_CTRL >> 3] >> IOMMU_CTRL_TSB_SHIFT) & 0x7;
+
+    if (is->regs[IOMMU_CTRL >> 3] & IOMMU_CTRL_TBW_SIZE) {
+        /* 64K */
+        switch (tsbsize) {
+        case 0:
+            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_64M) >> 13;
+            break;
+        case 1:
+            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_128M) >> 13;
+            break;
+        case 2:
+            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_256M) >> 13;
+            break;
+        case 3:
+            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_512M) >> 13;
+            break;
+        case 4:
+            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_1G) >> 13;
+            break;
+        case 5:
+            offset = (addr & IOMMU_TSB_64K_OFFSET_MASK_2G) >> 13;
+            break;
+        default:
+            /* Not implemented, error */
+            return ret;
+        }
+    } else {
+        /* 8K */
+        switch (tsbsize) {
+        case 0:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_8M) >> 10;
+            break;
+        case 1:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_16M) >> 10;
+            break;
+        case 2:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_32M) >> 10;
+            break;
+        case 3:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_64M) >> 10;
+            break;
+        case 4:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_128M) >> 10;
+            break;
+        case 5:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_256M) >> 10;
+            break;
+        case 6:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_512M) >> 10;
+            break;
+        case 7:
+            offset = (addr & IOMMU_TSB_8K_OFFSET_MASK_1G) >> 10;
+            break;
+        }
+    }
+
+    tte = address_space_ldq_be(&address_space_memory, baseaddr + offset,
+                               MEMTXATTRS_UNSPECIFIED, NULL);
+
+    if (!(tte & IOMMU_TTE_DATA_V)) {
+        /* Invalid mapping */
+        return ret;
+    }
+
+    if (tte & IOMMU_TTE_DATA_W) {
+        /* Writeable */
+        ret.perm = IOMMU_RW;
+    } else {
+        ret.perm = IOMMU_RO;
+    }
+
+    /* Extract phys */
+    if (tte & IOMMU_TTE_DATA_SIZE) {
+        /* 64K */
+        ret.iova = addr & IOMMU_PAGE_MASK_64K;
+        ret.translated_addr = tte & IOMMU_TTE_PHYS_MASK_64K;
+        ret.addr_mask = (IOMMU_PAGE_SIZE_64K - 1);
+    } else {
+        /* 8K */
+        ret.iova = addr & IOMMU_PAGE_MASK_8K;
+        ret.translated_addr = tte & IOMMU_TTE_PHYS_MASK_8K;
+        ret.addr_mask = (IOMMU_PAGE_SIZE_8K - 1);
+    }
+
+    trace_sun4u_iommu_translate(ret.iova, ret.translated_addr, tte);
+
+    return ret;
+}
+
+static void iommu_mem_write(void *opaque, hwaddr addr,
+                            uint64_t val, unsigned size)
+{
+    IOMMUState *is = opaque;
+
+    trace_sun4u_iommu_mem_write(addr, val, size);
+
+    switch (addr) {
+    case IOMMU_CTRL:
+        if (size == 4) {
+            is->regs[IOMMU_CTRL >> 3] &= 0xffffffffULL;
+            is->regs[IOMMU_CTRL >> 3] |= val << 32;
+        } else {
+            is->regs[IOMMU_CTRL >> 3] = val;
+        }
+        break;
+    case IOMMU_CTRL + 0x4:
+        is->regs[IOMMU_CTRL >> 3] &= 0xffffffff00000000ULL;
+        is->regs[IOMMU_CTRL >> 3] |= val & 0xffffffffULL;
+        break;
+    case IOMMU_BASE:
+        if (size == 4) {
+            is->regs[IOMMU_BASE >> 3] &= 0xffffffffULL;
+            is->regs[IOMMU_BASE >> 3] |= val << 32;
+        } else {
+            is->regs[IOMMU_BASE >> 3] = val;
+        }
+        break;
+    case IOMMU_BASE + 0x4:
+        is->regs[IOMMU_BASE >> 3] &= 0xffffffff00000000ULL;
+        is->regs[IOMMU_BASE >> 3] |= val & 0xffffffffULL;
+        break;
+    case IOMMU_FLUSH:
+    case IOMMU_FLUSH + 0x4:
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP,
+                  "sun4u-iommu: Unimplemented register write "
+                  "reg 0x%" HWADDR_PRIx " size 0x%x value 0x%" PRIx64 "\n",
+                  addr, size, val);
+        break;
+    }
+}
+
+static uint64_t iommu_mem_read(void *opaque, hwaddr addr, unsigned size)
+{
+    IOMMUState *is = opaque;
+    uint64_t val;
+
+    switch (addr) {
+    case IOMMU_CTRL:
+        if (size == 4) {
+            val = is->regs[IOMMU_CTRL >> 3] >> 32;
+        } else {
+            val = is->regs[IOMMU_CTRL >> 3];
+        }
+        break;
+    case IOMMU_CTRL + 0x4:
+        val = is->regs[IOMMU_CTRL >> 3] & 0xffffffffULL;
+        break;
+    case IOMMU_BASE:
+        if (size == 4) {
+            val = is->regs[IOMMU_BASE >> 3] >> 32;
+        } else {
+            val = is->regs[IOMMU_BASE >> 3];
+        }
+        break;
+    case IOMMU_BASE + 0x4:
+        val = is->regs[IOMMU_BASE >> 3] & 0xffffffffULL;
+        break;
+    case IOMMU_FLUSH:
+    case IOMMU_FLUSH + 0x4:
+        val = 0;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP,
+                      "sun4u-iommu: Unimplemented register read "
+                      "reg 0x%" HWADDR_PRIx " size 0x%x\n",
+                      addr, size);
+        val = 0;
+        break;
+    }
+
+    trace_sun4u_iommu_mem_read(addr, val, size);
+
+    return val;
+}
+
+static const MemoryRegionOps iommu_mem_ops = {
+    .read = iommu_mem_read,
+    .write = iommu_mem_write,
+    .endianness = DEVICE_BIG_ENDIAN,
+};
+
+static void iommu_reset(DeviceState *d)
+{
+    IOMMUState *s = SUN4U_IOMMU(d);
+
+    memset(s->regs, 0, IOMMU_NREGS * sizeof(uint64_t));
+}
+
+static void iommu_init(Object *obj)
+{
+    IOMMUState *s = SUN4U_IOMMU(obj);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+
+    memory_region_init_iommu(&s->iommu, sizeof(s->iommu),
+                             TYPE_SUN4U_IOMMU_MEMORY_REGION, OBJECT(s),
+                             "iommu-sun4u", UINT64_MAX);
+    address_space_init(&s->iommu_as, MEMORY_REGION(&s->iommu), "iommu-as");
+
+    memory_region_init_io(&s->iomem, obj, &iommu_mem_ops, s, "iommu",
+                          IOMMU_NREGS * sizeof(uint64_t));
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static void iommu_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = iommu_reset;
+}
+
+static const TypeInfo iommu_info = {
+    .name          = TYPE_SUN4U_IOMMU,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(IOMMUState),
+    .instance_init = iommu_init,
+    .class_init    = iommu_class_init,
+};
+
+static void sun4u_iommu_memory_region_class_init(ObjectClass *klass, void *data)
+{
+    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_CLASS(klass);
+
+    imrc->translate = sun4u_translate_iommu;
+}
+
+static const TypeInfo sun4u_iommu_memory_region_info = {
+    .parent = TYPE_IOMMU_MEMORY_REGION,
+    .name = TYPE_SUN4U_IOMMU_MEMORY_REGION,
+    .class_init = sun4u_iommu_memory_region_class_init,
+};
+
+static void iommu_register_types(void)
+{
+    type_register_static(&iommu_info);
+    type_register_static(&sun4u_iommu_memory_region_info);
+}
+
+type_init(iommu_register_types)
diff --git a/hw/sparc64/trace-events b/hw/sparc64/trace-events
new file mode 100644
index 0000000000..2ee2d75f70
--- /dev/null
+++ b/hw/sparc64/trace-events
@@ -0,0 +1,9 @@
+# See docs/devel/tracing.txt for syntax documentation.
+
+# hw/sparc64/sun4u.c
+ebus_isa_irq_handler(int n, int level) "Set ISA IRQ %d level %d"
+
+# hw/sparc64/sun4u_iommu.c
+sun4u_iommu_mem_read(uint64_t addr, uint64_t val, int size) "addr: 0x%"PRIx64" val: 0x%"PRIx64" size: %d"
+sun4u_iommu_mem_write(uint64_t addr, uint64_t val, int size) "addr: 0x%"PRIx64" val: 0x%"PRIx64" size: %d"
+sun4u_iommu_translate(uint64_t addr, uint64_t trans_addr, uint64_t tte) "xlate 0x%"PRIx64" => pa 0x%"PRIx64" tte: 0x%"PRIx64
diff --git a/hw/timer/slavio_timer.c b/hw/timer/slavio_timer.c
index a8cc9c0148..4694b653a7 100644
--- a/hw/timer/slavio_timer.c
+++ b/hw/timer/slavio_timer.c
@@ -23,7 +23,6 @@
  */
 
 #include "qemu/osdep.h"
-#include "hw/sparc/sun4m.h"
 #include "qemu/timer.h"
 #include "hw/ptimer.h"
 #include "hw/sysbus.h"
diff --git a/include/hw/pci-host/apb.h b/include/hw/pci-host/apb.h
index b19bd55c40..604d899b1e 100644
--- a/include/hw/pci-host/apb.h
+++ b/include/hw/pci-host/apb.h
@@ -1,10 +1,54 @@
 #ifndef PCI_HOST_APB_H
 #define PCI_HOST_APB_H
 
-#include "qemu-common.h"
+#include "hw/sparc/sun4u_iommu.h"
+
+#define MAX_IVEC 0x40
+
+/* OBIO IVEC IRQs */
+#define OBIO_HDD_IRQ         0x20
+#define OBIO_NIC_IRQ         0x21
+#define OBIO_LPT_IRQ         0x22
+#define OBIO_FDD_IRQ         0x27
+#define OBIO_KBD_IRQ         0x29
+#define OBIO_MSE_IRQ         0x2a
+#define OBIO_SER_IRQ         0x2b
+
+#define TYPE_APB "pbm"
+
+#define APB_DEVICE(obj) \
+    OBJECT_CHECK(APBState, (obj), TYPE_APB)
+
+typedef struct APBState {
+    PCIHostState parent_obj;
+
+    hwaddr special_base;
+    hwaddr mem_base;
+    MemoryRegion apb_config;
+    MemoryRegion pci_config;
+    MemoryRegion pci_mmio;
+    MemoryRegion pci_ioport;
+    uint64_t pci_irq_in;
+    IOMMUState *iommu;
+    PCIBridge *bridgeA;
+    PCIBridge *bridgeB;
+    uint32_t pci_control[16];
+    uint32_t pci_irq_map[8];
+    uint32_t pci_err_irq_map[4];
+    uint32_t obio_irq_map[32];
+    qemu_irq ivec_irqs[MAX_IVEC];
+    unsigned int irq_request;
+    uint32_t reset_control;
+    unsigned int nr_resets;
+} APBState;
+
+typedef struct PBMPCIBridge {
+    /*< private >*/
+    PCIBridge parent_obj;
+} PBMPCIBridge;
+
+#define TYPE_PBM_PCI_BRIDGE "pbm-bridge"
+#define PBM_PCI_BRIDGE(obj) \
+    OBJECT_CHECK(PBMPCIBridge, (obj), TYPE_PBM_PCI_BRIDGE)
 
-PCIBus *pci_apb_init(hwaddr special_base,
-                     hwaddr mem_base,
-                     qemu_irq *ivec_irqs, PCIBus **bus2, PCIBus **bus3,
-                     qemu_irq **pbm_irqs);
 #endif
diff --git a/include/hw/sparc/sparc64.h b/include/hw/sparc/sparc64.h
index ca3bb4be71..5af4344459 100644
--- a/include/hw/sparc/sparc64.h
+++ b/include/hw/sparc/sparc64.h
@@ -1,4 +1,6 @@
 
+#define IVEC_MAX             0x40
+
 SPARCCPU *sparc64_cpu_devinit(const char *cpu_type, uint64_t prom_addr);
 
 void sparc64_cpu_set_ivec_irq(void *opaque, int irq, int level);
diff --git a/include/hw/sparc/sun4m.h b/include/hw/sparc/sun4m.h
deleted file mode 100644
index c557b0dd53..0000000000
--- a/include/hw/sparc/sun4m.h
+++ /dev/null
@@ -1,35 +0,0 @@
-#ifndef SUN4M_H
-#define SUN4M_H
-
-#include "qemu-common.h"
-#include "exec/hwaddr.h"
-#include "qapi/qmp/types.h"
-#include "hw/sysbus.h"
-
-/* Devices used by sparc32 system.  */
-
-/* iommu.c */
-#define TYPE_SUN4M_IOMMU "sun4m-iommu"
-#define SUN4M_IOMMU(obj) OBJECT_CHECK(IOMMUState, (obj), TYPE_SUN4M_IOMMU)
-
-#define TYPE_SUN4M_IOMMU_MEMORY_REGION "sun4m-iommu-memory-region"
-
-#define IOMMU_NREGS         (4 * 4096 / 4)
-
-typedef struct IOMMUState {
-    SysBusDevice parent_obj;
-
-    AddressSpace iommu_as;
-    IOMMUMemoryRegion iommu;
-
-    MemoryRegion iomem;
-    uint32_t regs[IOMMU_NREGS];
-    hwaddr iostart;
-    qemu_irq irq;
-    uint32_t version;
-} IOMMUState;
-
-/* sparc32_dma.c */
-#include "hw/sparc/sparc32_dma.h"
-
-#endif
diff --git a/include/hw/sparc/sun4m_iommu.h b/include/hw/sparc/sun4m_iommu.h
new file mode 100644
index 0000000000..938937eb04
--- /dev/null
+++ b/include/hw/sparc/sun4m_iommu.h
@@ -0,0 +1,51 @@
+/*
+ * QEMU Sun4m iommu emulation
+ *
+ * Copyright (c) 2003-2005 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef SUN4M_IOMMU_H
+#define SUN4M_IOMMU_H
+
+#include "qemu-common.h"
+#include "hw/sysbus.h"
+
+#define IOMMU_NREGS         (4 * 4096 / 4)
+
+typedef struct IOMMUState {
+    SysBusDevice parent_obj;
+
+    AddressSpace iommu_as;
+    IOMMUMemoryRegion iommu;
+
+    MemoryRegion iomem;
+    uint32_t regs[IOMMU_NREGS];
+    hwaddr iostart;
+    qemu_irq irq;
+    uint32_t version;
+} IOMMUState;
+
+#define TYPE_SUN4M_IOMMU "sun4m-iommu"
+#define SUN4M_IOMMU(obj) OBJECT_CHECK(IOMMUState, (obj), TYPE_SUN4M_IOMMU)
+
+#define TYPE_SUN4M_IOMMU_MEMORY_REGION "sun4m-iommu-memory-region"
+
+#endif
diff --git a/include/hw/sparc/sun4u_iommu.h b/include/hw/sparc/sun4u_iommu.h
new file mode 100644
index 0000000000..a760172e8e
--- /dev/null
+++ b/include/hw/sparc/sun4u_iommu.h
@@ -0,0 +1,50 @@
+/*
+ * QEMU sun4u IOMMU emulation
+ *
+ * Copyright (c) 2006 Fabrice Bellard
+ * Copyright (c) 2012,2013 Artyom Tarasenko
+ * Copyright (c) 2017 Mark Cave-Ayland
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef SUN4U_IOMMU_H
+#define SUN4U_IOMMU_H
+
+#include "qemu-common.h"
+#include "hw/sysbus.h"
+
+#define IOMMU_NREGS             3
+
+typedef struct IOMMUState {
+    SysBusDevice parent_obj;
+
+    AddressSpace iommu_as;
+    IOMMUMemoryRegion iommu;
+
+    MemoryRegion iomem;
+    uint64_t regs[IOMMU_NREGS];
+} IOMMUState;
+
+#define TYPE_SUN4U_IOMMU "sun4u-iommu"
+#define SUN4U_IOMMU(obj) OBJECT_CHECK(IOMMUState, (obj), TYPE_SUN4U_IOMMU)
+
+#define TYPE_SUN4U_IOMMU_MEMORY_REGION "sun4u-iommu-memory-region"
+
+#endif
diff --git a/target/sparc/mmu_helper.c b/target/sparc/mmu_helper.c
index d5b6c1e48c..f2d2250e7a 100644
--- a/target/sparc/mmu_helper.c
+++ b/target/sparc/mmu_helper.c
@@ -857,18 +857,12 @@ hwaddr sparc_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
     CPUSPARCState *env = &cpu->env;
     hwaddr phys_addr;
     int mmu_idx = cpu_mmu_index(env, false);
-    MemoryRegionSection section;
 
     if (cpu_sparc_get_phys_page(env, &phys_addr, addr, 2, mmu_idx) != 0) {
         if (cpu_sparc_get_phys_page(env, &phys_addr, addr, 0, mmu_idx) != 0) {
             return -1;
         }
     }
-    section = memory_region_find(get_system_memory(), phys_addr, 1);
-    memory_region_unref(section.mr);
-    if (!int128_nz(section.size)) {
-        return -1;
-    }
     return phys_addr;
 }
 #endif