diff --git a/configs/common/FSConfig.py b/configs/common/FSConfig.py
index 6d7634106..44c13ef78 100644
--- a/configs/common/FSConfig.py
+++ b/configs/common/FSConfig.py
@@ -156,7 +156,7 @@ def makeLinuxMipsSystem(mem_mode, mdesc = None):
     return self
 
 def x86IOAddress(port):
-    IO_address_space_base = 0x1000000000000000
+    IO_address_space_base = 0x8000000000000000
     return IO_address_space_base + port;
 
 def makeLinuxX86System(mem_mode, mdesc = None):
@@ -189,6 +189,7 @@ def makeLinuxX86System(mem_mode, mdesc = None):
 
     # Platform
     self.opteron = Opteron()
+    self.opteron.attachIO(self.iobus)
 
     self.intrctrl = IntrControl()
 
diff --git a/src/arch/x86/miscregs.hh b/src/arch/x86/miscregs.hh
index 36b953526..2bf647150 100644
--- a/src/arch/x86/miscregs.hh
+++ b/src/arch/x86/miscregs.hh
@@ -339,6 +339,8 @@ namespace X86ISA
 
         //XXX Add "Model-Specific Registers"
 
+        MISCREG_PCI_CONFIG_ADDRESS,
+
         NUM_MISCREGS
     };
 
diff --git a/src/arch/x86/mmaped_ipr.hh b/src/arch/x86/mmaped_ipr.hh
index 9184ec4dc..36c0baaca 100644
--- a/src/arch/x86/mmaped_ipr.hh
+++ b/src/arch/x86/mmaped_ipr.hh
@@ -64,6 +64,7 @@
  * ISA-specific helper functions for memory mapped IPR accesses.
  */
 
+#include "arch/x86/miscregs.hh"
 #include "config/full_system.hh"
 #include "cpu/base.hh"
 #include "cpu/thread_context.hh"
@@ -88,8 +89,13 @@ namespace X86ISA
 #if !FULL_SYSTEM
         panic("Shouldn't have a memory mapped register in SE\n");
 #else
-        xc->setMiscReg(pkt->getAddr() / sizeof(MiscReg),
-                gtoh(pkt->get<uint64_t>()));
+        MiscRegIndex index = (MiscRegIndex)(pkt->getAddr() / sizeof(MiscReg));
+        if (index == MISCREG_PCI_CONFIG_ADDRESS) {
+            xc->setMiscReg(index, gtoh(pkt->get<uint32_t>()));
+        } else {
+            xc->setMiscReg(pkt->getAddr() / sizeof(MiscReg),
+                    gtoh(pkt->get<uint64_t>()));
+        }
 #endif
         return xc->getCpuPtr()->ticks(1);
     }
diff --git a/src/arch/x86/tlb.cc b/src/arch/x86/tlb.cc
index 2e6ea4a22..acac3081a 100644
--- a/src/arch/x86/tlb.cc
+++ b/src/arch/x86/tlb.cc
@@ -76,7 +76,7 @@
 
 namespace X86ISA {
 
-TLB::TLB(const Params *p) : SimObject(p), size(p->size)
+TLB::TLB(const Params *p) : SimObject(p), configAddress(0), size(p->size)
 {
     tlb = new TlbEntry[size];
     std::memset(tlb, 0, sizeof(TlbEntry) * size);
@@ -147,6 +147,12 @@ TLB::invalidateAll()
     }
 }
 
+void
+TLB::setConfigAddress(uint32_t addr)
+{
+    configAddress = addr;
+}
+
 void
 TLB::invalidateNonGlobal()
 {
@@ -478,7 +484,19 @@ TLB::translate(RequestPtr &req, ThreadContext *tc, bool write, bool execute)
             // Make sure the address fits in the expected 16 bit IO address
             // space.
             assert(!(IOPort & ~0xFFFF));
-            req->setPaddr(PhysAddrPrefixIO | IOPort);
+            if (IOPort == 0xCF8 && req->getSize() == 4) {
+                req->setMmapedIpr(true);
+                req->setPaddr(MISCREG_PCI_CONFIG_ADDRESS * sizeof(MiscReg));
+            } else if ((IOPort & ~mask(2)) == 0xCFC) {
+                Addr configAddress =
+                    tc->readMiscRegNoEffect(MISCREG_PCI_CONFIG_ADDRESS);
+                if (bits(configAddress, 31, 31)) {
+                    req->setPaddr(PhysAddrPrefixPciConfig |
+                            bits(configAddress, 30, 0));
+                }
+            } else {
+                req->setPaddr(PhysAddrPrefixIO | IOPort);
+            }
             return NoFault;
         } else {
             panic("Access to unrecognized internal address space %#x.\n",
diff --git a/src/arch/x86/tlb.hh b/src/arch/x86/tlb.hh
index a361c2291..d08d6fa68 100644
--- a/src/arch/x86/tlb.hh
+++ b/src/arch/x86/tlb.hh
@@ -90,6 +90,7 @@ namespace X86ISA
         friend class FakeDTLBFault;
 
         bool _allowNX;
+        uint32_t configAddress;
 
       public:
         bool allowNX() const
@@ -104,6 +105,8 @@ namespace X86ISA
 
         TlbEntry *lookup(Addr va, bool update_lru = true);
 
+        void setConfigAddress(uint32_t addr);
+
 #if FULL_SYSTEM
       protected:
 
diff --git a/src/arch/x86/x86_traits.hh b/src/arch/x86/x86_traits.hh
index dc71de500..d605ce218 100644
--- a/src/arch/x86/x86_traits.hh
+++ b/src/arch/x86/x86_traits.hh
@@ -88,7 +88,8 @@ namespace X86ISA
     const Addr IntAddrPrefixMSR = ULL(0x200000000);
     const Addr IntAddrPrefixIO = ULL(0x300000000);
 
-    const Addr PhysAddrPrefixIO = ULL(0x1000000000000000);
+    const Addr PhysAddrPrefixIO = ULL(0x8000000000000000);
+    const Addr PhysAddrPrefixPciConfig = ULL(0xC000000000000000);
 }
 
 #endif //__ARCH_X86_X86TRAITS_HH__
diff --git a/src/dev/x86/Opteron.py b/src/dev/x86/Opteron.py
index 435ecccb6..cb015e2e7 100644
--- a/src/dev/x86/Opteron.py
+++ b/src/dev/x86/Opteron.py
@@ -3,8 +3,16 @@ from m5.proxy import *
 from Device import BasicPioDevice, PioDevice, IsaFake, BadAddr
 from Uart import Uart8250
 from Platform import Platform
+from Pci import PciConfigAll
 from SimConsole import SimConsole
 
 class Opteron(Platform):
     type = 'Opteron'
     system = Param.System(Parent.any, "system")
+
+    pciconfig = PciConfigAll()
+
+    def attachIO(self, bus):
+        self.pciconfig.pio = bus.default
+        bus.responder_set = True
+        bus.responder = self.pciconfig
diff --git a/src/dev/x86/opteron.cc b/src/dev/x86/opteron.cc
index df28e58de..ba46f2dfa 100644
--- a/src/dev/x86/opteron.cc
+++ b/src/dev/x86/opteron.cc
@@ -36,6 +36,7 @@
 #include <string>
 #include <vector>
 
+#include "arch/x86/x86_traits.hh"
 #include "cpu/intr_control.hh"
 #include "dev/simconsole.hh"
 #include "dev/x86/opteron.hh"
@@ -95,8 +96,10 @@ Opteron::pciToDma(Addr pciAddr) const
 Addr
 Opteron::calcConfigAddr(int bus, int dev, int func)
 {
-    panic("Need implementation\n");
-    M5_DUMMY_RETURN
+    assert(func < 8);
+    assert(dev < 32);
+    assert(bus == 0);
+    return (PhysAddrPrefixPciConfig | (func << 8) | (dev << 11));
 }
 
 Opteron *