MEM: Enable multiple distributed generalized memories

This patch removes the assumption on having on single instance of
PhysicalMemory, and enables a distributed memory where the individual
memories in the system are each responsible for a single contiguous
address range.

All memories inherit from an AbstractMemory that encompasses the basic
behaviuor of a random access memory, and provides untimed access
methods. What was previously called PhysicalMemory is now
SimpleMemory, and a subclass of AbstractMemory. All future types of
memory controllers should inherit from AbstractMemory.

To enable e.g. the atomic CPU and RubyPort to access the now
distributed memory, the system has a wrapper class, called
PhysicalMemory that is aware of all the memories in the system and
their associated address ranges. This class thus acts as an
infinitely-fast bus and performs address decoding for these "shortcut"
accesses. Each memory can specify that it should not be part of the
global address map (used e.g. by the functional memories by some
testers). Moreover, each memory can be configured to be reported to
the OS configuration table, useful for populating ATAG structures, and
any potential ACPI tables.

Checkpointing support currently assumes that all memories have the
same size and organisation when creating and resuming from the
checkpoint. A future patch will enable a more flexible
re-organisation.

--HG--
rename : src/mem/PhysicalMemory.py => src/mem/AbstractMemory.py
rename : src/mem/PhysicalMemory.py => src/mem/SimpleMemory.py
rename : src/mem/physical.cc => src/mem/abstract_mem.cc
rename : src/mem/physical.hh => src/mem/abstract_mem.hh
rename : src/mem/physical.cc => src/mem/simple_mem.cc
rename : src/mem/physical.hh => src/mem/simple_mem.hh

11 files changed, 1283 insertions, 769 deletions

diff --git a/src/mem/AbstractMemory.py b/src/mem/AbstractMemory.py
new file mode 100644
index 000000000..bf1621f4d
--- /dev/null
+++ b/src/mem/AbstractMemory.py
@@ -0,0 +1,61 @@
+# Copyright (c) 2012 ARM Limited
+# All rights reserved.
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# Copyright (c) 2005-2008 The Regents of The University of Michigan
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Nathan Binkert
+#          Andreas Hansson
+
+from m5.params import *
+from MemObject import MemObject
+
+class AbstractMemory(MemObject):
+    type = 'AbstractMemory'
+    abstract = True
+    range = Param.AddrRange(AddrRange('128MB'), "Address range")
+    file = Param.String('', "Memory-mapped file")
+    null = Param.Bool(False, "Do not store data, always return zero")
+    zero = Param.Bool(False, "Initialize memory with zeros")
+
+    # All memories are passed to the global physical memory, and
+    # certain memories may be excluded from the global address map,
+    # e.g. by the testers that use shadow memories as a reference
+    in_addr_map = Param.Bool(True, "Memory part of the global address map")
+
+    # Should the bootloader include this memory when passing
+    # configuration information about the physical memory layout to
+    # the kernel, e.g. using ATAG or ACPI
+    conf_table_reported = Param.Bool(False, "Report to configuration table")
diff --git a/src/mem/SConscript b/src/mem/SConscript
index d30fd7fcb..efb3c947a 100644
--- a/src/mem/SConscript
+++ b/src/mem/SConscript
@@ -47,7 +47,10 @@ Source('fs_translating_port_proxy.cc')
 Source('se_translating_port_proxy.cc')
 
 if env['TARGET_ISA'] != 'no':
-    SimObject('PhysicalMemory.py')
+    SimObject('AbstractMemory.py')
+    SimObject('SimpleMemory.py')
+    Source('abstract_mem.cc')
+    Source('simple_mem.cc')
     Source('page_table.cc')
     Source('physical.cc')
 
diff --git a/src/mem/PhysicalMemory.py b/src/mem/SimpleMemory.py
index 756117972..51de3374d 100644
--- a/src/mem/PhysicalMemory.py
+++ b/src/mem/SimpleMemory.py
@@ -1,3 +1,15 @@
+# Copyright (c) 2012 ARM Limited
+# All rights reserved.
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
 # Copyright (c) 2005-2008 The Regents of The University of Michigan
 # All rights reserved.
 #
@@ -25,17 +37,13 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #
 # Authors: Nathan Binkert
+#          Andreas Hansson
 
 from m5.params import *
-from m5.proxy import *
-from MemObject import *
+from AbstractMemory import *
 
-class PhysicalMemory(MemObject):
-    type = 'PhysicalMemory'
-    port = VectorSlavePort("the access port")
-    range = Param.AddrRange(AddrRange('128MB'), "Device Address")
-    file = Param.String('', "memory mapped file")
-    latency = Param.Latency('30ns', "latency of an access")
-    latency_var = Param.Latency('0ns', "access variablity")
-    zero = Param.Bool(False, "zero initialize memory")
-    null = Param.Bool(False, "do not store data, always return zero")
+class SimpleMemory(AbstractMemory):
+    type = 'SimpleMemory'
+    port = VectorSlavePort("Slave ports")
+    latency = Param.Latency('30ns', "Request to response latency")
+    latency_var = Param.Latency('0ns', "Request to response latency variance")
diff --git a/src/mem/abstract_mem.cc b/src/mem/abstract_mem.cc
new file mode 100644
index 000000000..13a1183a2
--- /dev/null
+++ b/src/mem/abstract_mem.cc
@@ -0,0 +1,537 @@
+/*
+ * Copyright (c) 2010-2012 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * Copyright (c) 2001-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Ron Dreslinski
+ *          Ali Saidi
+ *          Andreas Hansson
+ */
+
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/user.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <zlib.h>
+
+#include <cerrno>
+#include <cstdio>
+#include <iostream>
+#include <string>
+
+#include "arch/registers.hh"
+#include "config/the_isa.hh"
+#include "debug/LLSC.hh"
+#include "debug/MemoryAccess.hh"
+#include "mem/abstract_mem.hh"
+#include "mem/packet_access.hh"
+
+using namespace std;
+
+AbstractMemory::AbstractMemory(const Params *p) :
+    MemObject(p), range(params()->range), pmemAddr(NULL),
+    confTableReported(p->conf_table_reported), inAddrMap(p->in_addr_map)
+{
+    if (size() % TheISA::PageBytes != 0)
+        panic("Memory Size not divisible by page size\n");
+
+    if (params()->null)
+        return;
+
+    if (params()->file == "") {
+        int map_flags = MAP_ANON | MAP_PRIVATE;
+        pmemAddr = (uint8_t *)mmap(NULL, size(),
+                                   PROT_READ | PROT_WRITE, map_flags, -1, 0);
+    } else {
+        int map_flags = MAP_PRIVATE;
+        int fd = open(params()->file.c_str(), O_RDONLY);
+        long _size = lseek(fd, 0, SEEK_END);
+        if (_size != range.size()) {
+            warn("Specified size %d does not match file %s %d\n", range.size(),
+                 params()->file, _size);
+            range = RangeSize(range.start, _size);
+        }
+        lseek(fd, 0, SEEK_SET);
+        pmemAddr = (uint8_t *)mmap(NULL, roundUp(_size, sysconf(_SC_PAGESIZE)),
+                                   PROT_READ | PROT_WRITE, map_flags, fd, 0);
+    }
+
+    if (pmemAddr == (void *)MAP_FAILED) {
+        perror("mmap");
+        if (params()->file == "")
+            fatal("Could not mmap!\n");
+        else
+            fatal("Could not find file: %s\n", params()->file);
+    }
+
+    //If requested, initialize all the memory to 0
+    if (p->zero)
+        memset(pmemAddr, 0, size());
+}
+
+
+AbstractMemory::~AbstractMemory()
+{
+    if (pmemAddr)
+        munmap((char*)pmemAddr, size());
+}
+
+void
+AbstractMemory::regStats()
+{
+    using namespace Stats;
+
+    bytesRead
+        .name(name() + ".bytes_read")
+        .desc("Number of bytes read from this memory")
+        ;
+    bytesInstRead
+        .name(name() + ".bytes_inst_read")
+        .desc("Number of instructions bytes read from this memory")
+        ;
+    bytesWritten
+        .name(name() + ".bytes_written")
+        .desc("Number of bytes written to this memory")
+        ;
+    numReads
+        .name(name() + ".num_reads")
+        .desc("Number of read requests responded to by this memory")
+        ;
+    numWrites
+        .name(name() + ".num_writes")
+        .desc("Number of write requests responded to by this memory")
+        ;
+    numOther
+        .name(name() + ".num_other")
+        .desc("Number of other requests responded to by this memory")
+        ;
+    bwRead
+        .name(name() + ".bw_read")
+        .desc("Total read bandwidth from this memory (bytes/s)")
+        .precision(0)
+        .prereq(bytesRead)
+        ;
+    bwInstRead
+        .name(name() + ".bw_inst_read")
+        .desc("Instruction read bandwidth from this memory (bytes/s)")
+        .precision(0)
+        .prereq(bytesInstRead)
+        ;
+    bwWrite
+        .name(name() + ".bw_write")
+        .desc("Write bandwidth from this memory (bytes/s)")
+        .precision(0)
+        .prereq(bytesWritten)
+        ;
+    bwTotal
+        .name(name() + ".bw_total")
+        .desc("Total bandwidth to/from this memory (bytes/s)")
+        .precision(0)
+        .prereq(bwTotal)
+        ;
+    bwRead = bytesRead / simSeconds;
+    bwInstRead = bytesInstRead / simSeconds;
+    bwWrite = bytesWritten / simSeconds;
+    bwTotal = (bytesRead + bytesWritten) / simSeconds;
+}
+
+Range<Addr>
+AbstractMemory::getAddrRange()
+{
+    return range;
+}
+
+// Add load-locked to tracking list.  Should only be called if the
+// operation is a load and the LLSC flag is set.
+void
+AbstractMemory::trackLoadLocked(PacketPtr pkt)
+{
+    Request *req = pkt->req;
+    Addr paddr = LockedAddr::mask(req->getPaddr());
+
+    // first we check if we already have a locked addr for this
+    // xc.  Since each xc only gets one, we just update the
+    // existing record with the new address.
+    list<LockedAddr>::iterator i;
+
+    for (i = lockedAddrList.begin(); i != lockedAddrList.end(); ++i) {
+        if (i->matchesContext(req)) {
+            DPRINTF(LLSC, "Modifying lock record: context %d addr %#x\n",
+                    req->contextId(), paddr);
+            i->addr = paddr;
+            return;
+        }
+    }
+
+    // no record for this xc: need to allocate a new one
+    DPRINTF(LLSC, "Adding lock record: context %d addr %#x\n",
+            req->contextId(), paddr);
+    lockedAddrList.push_front(LockedAddr(req));
+}
+
+
+// Called on *writes* only... both regular stores and
+// store-conditional operations.  Check for conventional stores which
+// conflict with locked addresses, and for success/failure of store
+// conditionals.
+bool
+AbstractMemory::checkLockedAddrList(PacketPtr pkt)
+{
+    Request *req = pkt->req;
+    Addr paddr = LockedAddr::mask(req->getPaddr());
+    bool isLLSC = pkt->isLLSC();
+
+    // Initialize return value.  Non-conditional stores always
+    // succeed.  Assume conditional stores will fail until proven
+    // otherwise.
+    bool success = !isLLSC;
+
+    // Iterate over list.  Note that there could be multiple matching
+    // records, as more than one context could have done a load locked
+    // to this location.
+    list<LockedAddr>::iterator i = lockedAddrList.begin();
+
+    while (i != lockedAddrList.end()) {
+
+        if (i->addr == paddr) {
+            // we have a matching address
+
+            if (isLLSC && i->matchesContext(req)) {
+                // it's a store conditional, and as far as the memory
+                // system can tell, the requesting context's lock is
+                // still valid.
+                DPRINTF(LLSC, "StCond success: context %d addr %#x\n",
+                        req->contextId(), paddr);
+                success = true;
+            }
+
+            // Get rid of our record of this lock and advance to next
+            DPRINTF(LLSC, "Erasing lock record: context %d addr %#x\n",
+                    i->contextId, paddr);
+            i = lockedAddrList.erase(i);
+        }
+        else {
+            // no match: advance to next record
+            ++i;
+        }
+    }
+
+    if (isLLSC) {
+        req->setExtraData(success ? 1 : 0);
+    }
+
+    return success;
+}
+
+
+#if TRACING_ON
+
+#define CASE(A, T)                                                      \
+  case sizeof(T):                                                       \
+    DPRINTF(MemoryAccess,"%s of size %i on address 0x%x data 0x%x\n",   \
+            A, pkt->getSize(), pkt->getAddr(), pkt->get<T>());          \
+  break
+
+
+#define TRACE_PACKET(A)                                                 \
+    do {                                                                \
+        switch (pkt->getSize()) {                                       \
+          CASE(A, uint64_t);                                            \
+          CASE(A, uint32_t);                                            \
+          CASE(A, uint16_t);                                            \
+          CASE(A, uint8_t);                                             \
+          default:                                                      \
+            DPRINTF(MemoryAccess, "%s of size %i on address 0x%x\n",    \
+                    A, pkt->getSize(), pkt->getAddr());                 \
+            DDUMP(MemoryAccess, pkt->getPtr<uint8_t>(), pkt->getSize());\
+        }                                                               \
+    } while (0)
+
+#else
+
+#define TRACE_PACKET(A)
+
+#endif
+
+void
+AbstractMemory::access(PacketPtr pkt)
+{
+    assert(pkt->getAddr() >= range.start &&
+           (pkt->getAddr() + pkt->getSize() - 1) <= range.end);
+
+    if (pkt->memInhibitAsserted()) {
+        DPRINTF(MemoryAccess, "mem inhibited on 0x%x: not responding\n",
+                pkt->getAddr());
+        return;
+    }
+
+    uint8_t *hostAddr = pmemAddr + pkt->getAddr() - range.start;
+
+    if (pkt->cmd == MemCmd::SwapReq) {
+        TheISA::IntReg overwrite_val;
+        bool overwrite_mem;
+        uint64_t condition_val64;
+        uint32_t condition_val32;
+
+        if (!pmemAddr)
+            panic("Swap only works if there is real memory (i.e. null=False)");
+        assert(sizeof(TheISA::IntReg) >= pkt->getSize());
+
+        overwrite_mem = true;
+        // keep a copy of our possible write value, and copy what is at the
+        // memory address into the packet
+        std::memcpy(&overwrite_val, pkt->getPtr<uint8_t>(), pkt->getSize());
+        std::memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
+
+        if (pkt->req->isCondSwap()) {
+            if (pkt->getSize() == sizeof(uint64_t)) {
+                condition_val64 = pkt->req->getExtraData();
+                overwrite_mem = !std::memcmp(&condition_val64, hostAddr,
+                                             sizeof(uint64_t));
+            } else if (pkt->getSize() == sizeof(uint32_t)) {
+                condition_val32 = (uint32_t)pkt->req->getExtraData();
+                overwrite_mem = !std::memcmp(&condition_val32, hostAddr,
+                                             sizeof(uint32_t));
+            } else
+                panic("Invalid size for conditional read/write\n");
+        }
+
+        if (overwrite_mem)
+            std::memcpy(hostAddr, &overwrite_val, pkt->getSize());
+
+        assert(!pkt->req->isInstFetch());
+        TRACE_PACKET("Read/Write");
+        numOther++;
+    } else if (pkt->isRead()) {
+        assert(!pkt->isWrite());
+        if (pkt->isLLSC()) {
+            trackLoadLocked(pkt);
+        }
+        if (pmemAddr)
+            memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
+        TRACE_PACKET(pkt->req->isInstFetch() ? "IFetch" : "Read");
+        numReads++;
+        bytesRead += pkt->getSize();
+        if (pkt->req->isInstFetch())
+            bytesInstRead += pkt->getSize();
+    } else if (pkt->isWrite()) {
+        if (writeOK(pkt)) {
+            if (pmemAddr)
+                memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
+            assert(!pkt->req->isInstFetch());
+            TRACE_PACKET("Write");
+            numWrites++;
+            bytesWritten += pkt->getSize();
+        }
+    } else if (pkt->isInvalidate()) {
+        // no need to do anything
+    } else {
+        panic("unimplemented");
+    }
+
+    if (pkt->needsResponse()) {
+        pkt->makeResponse();
+    }
+}
+
+void
+AbstractMemory::functionalAccess(PacketPtr pkt)
+{
+    assert(pkt->getAddr() >= range.start &&
+           (pkt->getAddr() + pkt->getSize() - 1) <= range.end);
+
+    uint8_t *hostAddr = pmemAddr + pkt->getAddr() - range.start;
+
+    if (pkt->isRead()) {
+        if (pmemAddr)
+            memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
+        TRACE_PACKET("Read");
+        pkt->makeResponse();
+    } else if (pkt->isWrite()) {
+        if (pmemAddr)
+            memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
+        TRACE_PACKET("Write");
+        pkt->makeResponse();
+    } else if (pkt->isPrint()) {
+        Packet::PrintReqState *prs =
+            dynamic_cast<Packet::PrintReqState*>(pkt->senderState);
+        // Need to call printLabels() explicitly since we're not going
+        // through printObj().
+        prs->printLabels();
+        // Right now we just print the single byte at the specified address.
+        ccprintf(prs->os, "%s%#x\n", prs->curPrefix(), *hostAddr);
+    } else {
+        panic("AbstractMemory: unimplemented functional command %s",
+              pkt->cmdString());
+    }
+}
+
+void
+AbstractMemory::serialize(ostream &os)
+{
+    if (!pmemAddr)
+        return;
+
+    gzFile compressedMem;
+    string filename = name() + ".physmem";
+    long _size = range.size();
+
+    SERIALIZE_SCALAR(filename);
+    SERIALIZE_SCALAR(_size);
+
+    // write memory file
+    string thefile = Checkpoint::dir() + "/" + filename.c_str();
+    int fd = creat(thefile.c_str(), 0664);
+    if (fd < 0) {
+        perror("creat");
+        fatal("Can't open physical memory checkpoint file '%s'\n", filename);
+    }
+
+    compressedMem = gzdopen(fd, "wb");
+    if (compressedMem == NULL)
+        fatal("Insufficient memory to allocate compression state for %s\n",
+                filename);
+
+    if (gzwrite(compressedMem, pmemAddr, size()) != (int)size()) {
+        fatal("Write failed on physical memory checkpoint file '%s'\n",
+              filename);
+    }
+
+    if (gzclose(compressedMem))
+        fatal("Close failed on physical memory checkpoint file '%s'\n",
+              filename);
+
+    list<LockedAddr>::iterator i = lockedAddrList.begin();
+
+    vector<Addr> lal_addr;
+    vector<int> lal_cid;
+    while (i != lockedAddrList.end()) {
+        lal_addr.push_back(i->addr);
+        lal_cid.push_back(i->contextId);
+        i++;
+    }
+    arrayParamOut(os, "lal_addr", lal_addr);
+    arrayParamOut(os, "lal_cid", lal_cid);
+}
+
+void
+AbstractMemory::unserialize(Checkpoint *cp, const string &section)
+{
+    if (!pmemAddr)
+        return;
+
+    gzFile compressedMem;
+    long *tempPage;
+    long *pmem_current;
+    uint64_t curSize;
+    uint32_t bytesRead;
+    const uint32_t chunkSize = 16384;
+
+    string filename;
+
+    UNSERIALIZE_SCALAR(filename);
+
+    filename = cp->cptDir + "/" + filename;
+
+    // mmap memoryfile
+    int fd = open(filename.c_str(), O_RDONLY);
+    if (fd < 0) {
+        perror("open");
+        fatal("Can't open physical memory checkpoint file '%s'", filename);
+    }
+
+    compressedMem = gzdopen(fd, "rb");
+    if (compressedMem == NULL)
+        fatal("Insufficient memory to allocate compression state for %s\n",
+                filename);
+
+    // unmap file that was mmapped in the constructor
+    // This is done here to make sure that gzip and open don't muck with our
+    // nice large space of memory before we reallocate it
+    munmap((char*)pmemAddr, size());
+
+    long _size;
+    UNSERIALIZE_SCALAR(_size);
+    if (_size > params()->range.size())
+        fatal("Memory size has changed! size %lld, param size %lld\n",
+              _size, params()->range.size());
+
+    pmemAddr = (uint8_t *)mmap(NULL, size(),
+        PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
+
+    if (pmemAddr == (void *)MAP_FAILED) {
+        perror("mmap");
+        fatal("Could not mmap physical memory!\n");
+    }
+
+    curSize = 0;
+    tempPage = (long*)malloc(chunkSize);
+    if (tempPage == NULL)
+        fatal("Unable to malloc memory to read file %s\n", filename);
+
+    /* Only copy bytes that are non-zero, so we don't give the VM system hell */
+    while (curSize < size()) {
+        bytesRead = gzread(compressedMem, tempPage, chunkSize);
+        if (bytesRead == 0)
+            break;
+
+        assert(bytesRead % sizeof(long) == 0);
+
+        for (uint32_t x = 0; x < bytesRead / sizeof(long); x++)
+        {
+             if (*(tempPage+x) != 0) {
+                 pmem_current = (long*)(pmemAddr + curSize + x * sizeof(long));
+                 *pmem_current = *(tempPage+x);
+             }
+        }
+        curSize += bytesRead;
+    }
+
+    free(tempPage);
+
+    if (gzclose(compressedMem))
+        fatal("Close failed on physical memory checkpoint file '%s'\n",
+              filename);
+
+    vector<Addr> lal_addr;
+    vector<int> lal_cid;
+    arrayParamIn(cp, section, "lal_addr", lal_addr);
+    arrayParamIn(cp, section, "lal_cid", lal_cid);
+    for(int i = 0; i < lal_addr.size(); i++)
+        lockedAddrList.push_front(LockedAddr(lal_addr[i], lal_cid[i]));
+}
diff --git a/src/mem/abstract_mem.hh b/src/mem/abstract_mem.hh
new file mode 100644
index 000000000..42ad08e5c
--- /dev/null
+++ b/src/mem/abstract_mem.hh
@@ -0,0 +1,250 @@
+/*
+ * Copyright (c) 2012 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * Copyright (c) 2001-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Ron Dreslinski
+ *          Andreas Hansson
+ */
+
+/**
+ * @file
+ * AbstractMemory declaration
+ */
+
+#ifndef __ABSTRACT_MEMORY_HH__
+#define __ABSTRACT_MEMORY_HH__
+
+#include "mem/mem_object.hh"
+#include "params/AbstractMemory.hh"
+#include "sim/stats.hh"
+
+/**
+ * An abstract memory represents a contiguous block of physical
+ * memory, with an associated address range, and also provides basic
+ * functionality for reading and writing this memory without any
+ * timing information. It is a MemObject since any subclass must have
+ * at least one slave port.
+ */
+class AbstractMemory : public MemObject
+{
+  protected:
+
+    // Address range of this memory
+    Range<Addr> range;
+
+    // Pointer to host memory used to implement this memory
+    uint8_t* pmemAddr;
+
+    // Enable specific memories to be reported to the configuration table
+    bool confTableReported;
+
+    // Should the memory appear in the global address map
+    bool inAddrMap;
+
+    class LockedAddr {
+
+      public:
+        // on alpha, minimum LL/SC granularity is 16 bytes, so lower
+        // bits need to masked off.
+        static const Addr Addr_Mask = 0xf;
+
+        static Addr mask(Addr paddr) { return (paddr & ~Addr_Mask); }
+
+        Addr addr;      // locked address
+        int contextId;     // locking hw context
+
+        // check for matching execution context
+        bool matchesContext(Request *req)
+        {
+            return (contextId == req->contextId());
+        }
+
+        LockedAddr(Request *req) : addr(mask(req->getPaddr())),
+                                   contextId(req->contextId())
+        {
+        }
+        // constructor for unserialization use
+        LockedAddr(Addr _addr, int _cid) : addr(_addr), contextId(_cid)
+        {
+        }
+    };
+
+    std::list<LockedAddr> lockedAddrList;
+
+    // helper function for checkLockedAddrs(): we really want to
+    // inline a quick check for an empty locked addr list (hopefully
+    // the common case), and do the full list search (if necessary) in
+    // this out-of-line function
+    bool checkLockedAddrList(PacketPtr pkt);
+
+    // Record the address of a load-locked operation so that we can
+    // clear the execution context's lock flag if a matching store is
+    // performed
+    void trackLoadLocked(PacketPtr pkt);
+
+    // Compare a store address with any locked addresses so we can
+    // clear the lock flag appropriately.  Return value set to 'false'
+    // if store operation should be suppressed (because it was a
+    // conditional store and the address was no longer locked by the
+    // requesting execution context), 'true' otherwise.  Note that
+    // this method must be called on *all* stores since even
+    // non-conditional stores must clear any matching lock addresses.
+    bool writeOK(PacketPtr pkt) {
+        Request *req = pkt->req;
+        if (lockedAddrList.empty()) {
+            // no locked addrs: nothing to check, store_conditional fails
+            bool isLLSC = pkt->isLLSC();
+            if (isLLSC) {
+                req->setExtraData(0);
+            }
+            return !isLLSC; // only do write if not an sc
+        } else {
+            // iterate over list...
+            return checkLockedAddrList(pkt);
+        }
+    }
+
+    /** Number of total bytes read from this memory */
+    Stats::Scalar bytesRead;
+    /** Number of instruction bytes read from this memory */
+    Stats::Scalar bytesInstRead;
+    /** Number of bytes written to this memory */
+    Stats::Scalar bytesWritten;
+    /** Number of read requests */
+    Stats::Scalar numReads;
+    /** Number of write requests */
+    Stats::Scalar numWrites;
+    /** Number of other requests */
+    Stats::Scalar numOther;
+    /** Read bandwidth from this memory */
+    Stats::Formula bwRead;
+    /** Read bandwidth from this memory */
+    Stats::Formula bwInstRead;
+    /** Write bandwidth from this memory */
+    Stats::Formula bwWrite;
+    /** Total bandwidth from this memory */
+    Stats::Formula bwTotal;
+
+  private:
+
+    // Prevent copying
+    AbstractMemory(const AbstractMemory&);
+
+    // Prevent assignment
+    AbstractMemory& operator=(const AbstractMemory&);
+
+  public:
+
+    typedef AbstractMemoryParams Params;
+
+    AbstractMemory(const Params* p);
+    virtual ~AbstractMemory();
+
+    const Params *
+    params() const
+    {
+        return dynamic_cast<const Params *>(_params);
+    }
+
+    /**
+     * Get the address range
+     *
+     * @return a single contigous address range
+     */
+    Range<Addr> getAddrRange();
+
+    /**
+     * Get the memory size.
+     *
+     * @return the size of the memory
+     */
+    uint64_t size() { return range.size(); }
+
+    /**
+     * Get the start address.
+     *
+     * @return the start address of the memory
+     */
+    Addr start() { return range.start; }
+
+    /**
+     *  Should this memory be passed to the kernel and part of the OS
+     *  physical memory layout.
+     *
+     * @return if this memory is reported
+     */
+    bool isConfReported() const { return confTableReported; }
+
+    /**
+     * Some memories are used as shadow memories or should for other
+     * reasons not be part of the global address map.
+     *
+     * @return if this memory is part of the address map
+     */
+    bool isInAddrMap() const { return inAddrMap; }
+
+    /**
+     * Perform an untimed memory access and update all the state
+     * (e.g. locked addresses) and statistics accordingly. The packet
+     * is turned into a response if required.
+     *
+     * @param pkt Packet performing the access
+     */
+    void access(PacketPtr pkt);
+
+    /**
+     * Perform an untimed memory read or write without changing
+     * anything but the memory itself. No stats are affected by this
+     * access. In addition to normal accesses this also facilitates
+     * print requests.
+     *
+     * @param pkt Packet performing the access
+     */
+    void functionalAccess(PacketPtr pkt);
+
+    /**
+     * Register Statistics
+     */
+    virtual void regStats();
+
+    virtual void serialize(std::ostream &os);
+    virtual void unserialize(Checkpoint *cp, const std::string &section);
+
+};
+
+#endif //__ABSTRACT_MEMORY_HH__
diff --git a/src/mem/cache/mshr.cc b/src/mem/cache/mshr.cc
index 821a3635b..6da779538 100644
--- a/src/mem/cache/mshr.cc
+++ b/src/mem/cache/mshr.cc
@@ -331,7 +331,7 @@ MSHR::handleSnoop(PacketPtr pkt, Counter _order)
         //    to forward the snoop up the hierarchy after the current
         //    transaction completes.
         
-        // Actual target device (typ. PhysicalMemory) will delete the
+        // Actual target device (typ. a memory) will delete the
         // packet on reception, so we need to save a copy here.
         PacketPtr cp_pkt = new Packet(pkt, true);
         targets->add(cp_pkt, curTick(), _order, Target::FromSnoop,
diff --git a/src/mem/physical.cc b/src/mem/physical.cc
index 78181b7df..5f92976f9 100644
--- a/src/mem/physical.cc
+++ b/src/mem/physical.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010-2011 ARM Limited
+ * Copyright (c) 2012 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -11,9 +11,6 @@
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
- * Copyright (c) 2001-2005 The Regents of The University of Michigan
- * All rights reserved.
- *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met: redistributions of source code must retain the above copyright
@@ -37,618 +34,93 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- * Authors: Ron Dreslinski
- *          Ali Saidi
+ * Authors: Andreas Hansson
  */
 
-#include <sys/mman.h>
-#include <sys/types.h>
-#include <sys/user.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <zlib.h>
-
-#include <cerrno>
-#include <cstdio>
-#include <iostream>
-#include <string>
-
-#include "arch/isa_traits.hh"
-#include "arch/registers.hh"
-#include "base/intmath.hh"
-#include "base/misc.hh"
-#include "base/random.hh"
-#include "base/types.hh"
-#include "config/the_isa.hh"
-#include "debug/LLSC.hh"
-#include "debug/MemoryAccess.hh"
-#include "mem/packet_access.hh"
+#include "debug/BusAddrRanges.hh"
 #include "mem/physical.hh"
-#include "sim/eventq.hh"
 
 using namespace std;
-using namespace TheISA;
-
-PhysicalMemory::PhysicalMemory(const Params *p)
-    : MemObject(p), pmemAddr(NULL), lat(p->latency), lat_var(p->latency_var),
-      _size(params()->range.size()), _start(params()->range.start)
-{
-    if (size() % TheISA::PageBytes != 0)
-        panic("Memory Size not divisible by page size\n");
-
-    // create the appropriate number of ports
-    for (int i = 0; i < p->port_port_connection_count; ++i) {
-        ports.push_back(new MemoryPort(csprintf("%s-port%d", name(), i),
-                                       this));
-    }
-
-    if (params()->null)
-        return;
-
-
-    if (params()->file == "") {
-        int map_flags = MAP_ANON | MAP_PRIVATE;
-        pmemAddr = (uint8_t *)mmap(NULL, size(),
-                                   PROT_READ | PROT_WRITE, map_flags, -1, 0);
-    } else {
-        int map_flags = MAP_PRIVATE;
-        int fd = open(params()->file.c_str(), O_RDONLY);
-        _size = lseek(fd, 0, SEEK_END);
-        lseek(fd, 0, SEEK_SET);
-        pmemAddr = (uint8_t *)mmap(NULL, roundUp(size(), sysconf(_SC_PAGESIZE)),
-                                   PROT_READ | PROT_WRITE, map_flags, fd, 0);
-    }
-
-    if (pmemAddr == (void *)MAP_FAILED) {
-        perror("mmap");
-        if (params()->file == "")
-            fatal("Could not mmap!\n");
-        else
-            fatal("Could not find file: %s\n", params()->file);
-    }
-
-    //If requested, initialize all the memory to 0
-    if (p->zero)
-        memset(pmemAddr, 0, size());
-}
-
-void
-PhysicalMemory::init()
-{
-    for (PortIterator p = ports.begin(); p != ports.end(); ++p) {
-        if (!(*p)->isConnected()) {
-            fatal("PhysicalMemory port %s is unconnected!\n", (*p)->name());
-        } else {
-            (*p)->sendRangeChange();
-        }
-    }
-}
-
-PhysicalMemory::~PhysicalMemory()
-{
-    if (pmemAddr)
-        munmap((char*)pmemAddr, size());
-}
-
-void
-PhysicalMemory::regStats()
-{
-    using namespace Stats;
-
-    bytesRead
-        .name(name() + ".bytes_read")
-        .desc("Number of bytes read from this memory")
-        ;
-    bytesInstRead
-        .name(name() + ".bytes_inst_read")
-        .desc("Number of instructions bytes read from this memory")
-        ;
-    bytesWritten
-        .name(name() + ".bytes_written")
-        .desc("Number of bytes written to this memory")
-        ;
-    numReads
-        .name(name() + ".num_reads")
-        .desc("Number of read requests responded to by this memory")
-        ;
-    numWrites
-        .name(name() + ".num_writes")
-        .desc("Number of write requests responded to by this memory")
-        ;
-    numOther
-        .name(name() + ".num_other")
-        .desc("Number of other requests responded to by this memory")
-        ;
-    bwRead
-        .name(name() + ".bw_read")
-        .desc("Total read bandwidth from this memory (bytes/s)")
-        .precision(0)
-        .prereq(bytesRead)
-        ;
-    bwInstRead
-        .name(name() + ".bw_inst_read")
-        .desc("Instruction read bandwidth from this memory (bytes/s)")
-        .precision(0)
-        .prereq(bytesInstRead)
-        ;
-    bwWrite
-        .name(name() + ".bw_write")
-        .desc("Write bandwidth from this memory (bytes/s)")
-        .precision(0)
-        .prereq(bytesWritten)
-        ;
-    bwTotal
-        .name(name() + ".bw_total")
-        .desc("Total bandwidth to/from this memory (bytes/s)")
-        .precision(0)
-        .prereq(bwTotal)
-        ;
-    bwRead = bytesRead / simSeconds;
-    bwInstRead = bytesInstRead / simSeconds;
-    bwWrite = bytesWritten / simSeconds;
-    bwTotal = (bytesRead + bytesWritten) / simSeconds;
-}
 
-unsigned
-PhysicalMemory::deviceBlockSize() const
-{
-    //Can accept anysize request
-    return 0;
-}
-
-Tick
-PhysicalMemory::calculateLatency(PacketPtr pkt)
-{
-    Tick latency = lat;
-    if (lat_var != 0)
-        latency += random_mt.random<Tick>(0, lat_var);
-    return latency;
-}
-
-
-
-// Add load-locked to tracking list.  Should only be called if the
-// operation is a load and the LLSC flag is set.
-void
-PhysicalMemory::trackLoadLocked(PacketPtr pkt)
+PhysicalMemory::PhysicalMemory(const vector<AbstractMemory*>& _memories) :
+    size(0)
 {
-    Request *req = pkt->req;
-    Addr paddr = LockedAddr::mask(req->getPaddr());
+    for (vector<AbstractMemory*>::const_iterator m = _memories.begin();
+         m != _memories.end(); ++m) {
+        // only add the memory if it is part of the global address map
+        if ((*m)->isInAddrMap()) {
+            memories.push_back(*m);
 
-    // first we check if we already have a locked addr for this
-    // xc.  Since each xc only gets one, we just update the
-    // existing record with the new address.
-    list<LockedAddr>::iterator i;
+            // calculate the total size once and for all
+            size += (*m)->size();
 
-    for (i = lockedAddrList.begin(); i != lockedAddrList.end(); ++i) {
-        if (i->matchesContext(req)) {
-            DPRINTF(LLSC, "Modifying lock record: context %d addr %#x\n",
-                    req->contextId(), paddr);
-            i->addr = paddr;
-            return;
+            // add the range to our interval tree and make sure it does not
+            // intersect an existing range
+            if (addrMap.insert((*m)->getAddrRange(), *m) == addrMap.end())
+                fatal("Memory address range for %s is overlapping\n",
+                      (*m)->name());
         }
+        DPRINTF(BusAddrRanges,
+                "Skipping memory %s that is not in global address map\n",
+                (*m)->name());
     }
-
-    // no record for this xc: need to allocate a new one
-    DPRINTF(LLSC, "Adding lock record: context %d addr %#x\n",
-            req->contextId(), paddr);
-    lockedAddrList.push_front(LockedAddr(req));
+    rangeCache.invalidate();
 }
 
-
-// Called on *writes* only... both regular stores and
-// store-conditional operations.  Check for conventional stores which
-// conflict with locked addresses, and for success/failure of store
-// conditionals.
 bool
-PhysicalMemory::checkLockedAddrList(PacketPtr pkt)
-{
-    Request *req = pkt->req;
-    Addr paddr = LockedAddr::mask(req->getPaddr());
-    bool isLLSC = pkt->isLLSC();
-
-    // Initialize return value.  Non-conditional stores always
-    // succeed.  Assume conditional stores will fail until proven
-    // otherwise.
-    bool success = !isLLSC;
-
-    // Iterate over list.  Note that there could be multiple matching
-    // records, as more than one context could have done a load locked
-    // to this location.
-    list<LockedAddr>::iterator i = lockedAddrList.begin();
-
-    while (i != lockedAddrList.end()) {
-
-        if (i->addr == paddr) {
-            // we have a matching address
-
-            if (isLLSC && i->matchesContext(req)) {
-                // it's a store conditional, and as far as the memory
-                // system can tell, the requesting context's lock is
-                // still valid.
-                DPRINTF(LLSC, "StCond success: context %d addr %#x\n",
-                        req->contextId(), paddr);
-                success = true;
-            }
-
-            // Get rid of our record of this lock and advance to next
-            DPRINTF(LLSC, "Erasing lock record: context %d addr %#x\n",
-                    i->contextId, paddr);
-            i = lockedAddrList.erase(i);
-        }
-        else {
-            // no match: advance to next record
-            ++i;
+PhysicalMemory::isMemAddr(Addr addr) const
+{
+    // see if the address is within the last matched range
+    if (addr != rangeCache) {
+        // lookup in the interval tree
+        range_map<Addr, AbstractMemory*>::const_iterator r =
+            addrMap.find(addr);
+        if (r == addrMap.end()) {
+            // not in the cache, and not in the tree
+            return false;
         }
+        // the range is in the tree, update the cache
+        rangeCache = r->first;
     }
 
-    if (isLLSC) {
-        req->setExtraData(success ? 1 : 0);
-    }
-
-    return success;
-}
-
-
-#if TRACING_ON
-
-#define CASE(A, T)                                                      \
-  case sizeof(T):                                                       \
-    DPRINTF(MemoryAccess,"%s of size %i on address 0x%x data 0x%x\n",   \
-            A, pkt->getSize(), pkt->getAddr(), pkt->get<T>());          \
-  break
-
-
-#define TRACE_PACKET(A)                                                 \
-    do {                                                                \
-        switch (pkt->getSize()) {                                       \
-          CASE(A, uint64_t);                                            \
-          CASE(A, uint32_t);                                            \
-          CASE(A, uint16_t);                                            \
-          CASE(A, uint8_t);                                             \
-          default:                                                      \
-            DPRINTF(MemoryAccess, "%s of size %i on address 0x%x\n",    \
-                    A, pkt->getSize(), pkt->getAddr());                 \
-            DDUMP(MemoryAccess, pkt->getPtr<uint8_t>(), pkt->getSize());\
-        }                                                               \
-    } while (0)
-
-#else
-
-#define TRACE_PACKET(A)
-
-#endif
-
-Tick
-PhysicalMemory::doAtomicAccess(PacketPtr pkt)
-{
-    assert(pkt->getAddr() >= start() &&
-           pkt->getAddr() + pkt->getSize() <= start() + size());
-
-    if (pkt->memInhibitAsserted()) {
-        DPRINTF(MemoryAccess, "mem inhibited on 0x%x: not responding\n",
-                pkt->getAddr());
-        return 0;
-    }
-
-    uint8_t *hostAddr = pmemAddr + pkt->getAddr() - start();
-
-    if (pkt->cmd == MemCmd::SwapReq) {
-        IntReg overwrite_val;
-        bool overwrite_mem;
-        uint64_t condition_val64;
-        uint32_t condition_val32;
-
-        if (!pmemAddr)
-            panic("Swap only works if there is real memory (i.e. null=False)");
-        assert(sizeof(IntReg) >= pkt->getSize());
-
-        overwrite_mem = true;
-        // keep a copy of our possible write value, and copy what is at the
-        // memory address into the packet
-        std::memcpy(&overwrite_val, pkt->getPtr<uint8_t>(), pkt->getSize());
-        std::memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
+    assert(addrMap.find(addr) != addrMap.end());
 
-        if (pkt->req->isCondSwap()) {
-            if (pkt->getSize() == sizeof(uint64_t)) {
-                condition_val64 = pkt->req->getExtraData();
-                overwrite_mem = !std::memcmp(&condition_val64, hostAddr,
-                                             sizeof(uint64_t));
-            } else if (pkt->getSize() == sizeof(uint32_t)) {
-                condition_val32 = (uint32_t)pkt->req->getExtraData();
-                overwrite_mem = !std::memcmp(&condition_val32, hostAddr,
-                                             sizeof(uint32_t));
-            } else
-                panic("Invalid size for conditional read/write\n");
-        }
-
-        if (overwrite_mem)
-            std::memcpy(hostAddr, &overwrite_val, pkt->getSize());
-
-        assert(!pkt->req->isInstFetch());
-        TRACE_PACKET("Read/Write");
-        numOther++;
-    } else if (pkt->isRead()) {
-        assert(!pkt->isWrite());
-        if (pkt->isLLSC()) {
-            trackLoadLocked(pkt);
-        }
-        if (pmemAddr)
-            memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
-        TRACE_PACKET(pkt->req->isInstFetch() ? "IFetch" : "Read");
-        numReads++;
-        bytesRead += pkt->getSize();
-        if (pkt->req->isInstFetch())
-            bytesInstRead += pkt->getSize();
-    } else if (pkt->isWrite()) {
-        if (writeOK(pkt)) {
-            if (pmemAddr)
-                memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
-            assert(!pkt->req->isInstFetch());
-            TRACE_PACKET("Write");
-            numWrites++;
-            bytesWritten += pkt->getSize();
-        }
-    } else if (pkt->isInvalidate()) {
-        //upgrade or invalidate
-        if (pkt->needsResponse()) {
-            pkt->makeAtomicResponse();
-        }
-    } else {
-        panic("unimplemented");
-    }
-
-    if (pkt->needsResponse()) {
-        pkt->makeAtomicResponse();
-    }
-    return calculateLatency(pkt);
-}
-
-
-void
-PhysicalMemory::doFunctionalAccess(PacketPtr pkt)
-{
-    assert(pkt->getAddr() >= start() &&
-           pkt->getAddr() + pkt->getSize() <= start() + size());
-
-
-    uint8_t *hostAddr = pmemAddr + pkt->getAddr() - start();
-
-    if (pkt->isRead()) {
-        if (pmemAddr)
-            memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
-        TRACE_PACKET("Read");
-        pkt->makeAtomicResponse();
-    } else if (pkt->isWrite()) {
-        if (pmemAddr)
-            memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
-        TRACE_PACKET("Write");
-        pkt->makeAtomicResponse();
-    } else if (pkt->isPrint()) {
-        Packet::PrintReqState *prs =
-            dynamic_cast<Packet::PrintReqState*>(pkt->senderState);
-        // Need to call printLabels() explicitly since we're not going
-        // through printObj().
-        prs->printLabels();
-        // Right now we just print the single byte at the specified address.
-        ccprintf(prs->os, "%s%#x\n", prs->curPrefix(), *hostAddr);
-    } else {
-        panic("PhysicalMemory: unimplemented functional command %s",
-              pkt->cmdString());
-    }
-}
-
-
-SlavePort &
-PhysicalMemory::getSlavePort(const std::string &if_name, int idx)
-{
-    if (if_name != "port") {
-        return MemObject::getSlavePort(if_name, idx);
-    } else {
-        if (idx >= static_cast<int>(ports.size())) {
-            fatal("PhysicalMemory::getSlavePort: unknown index %d\n", idx);
-        }
-
-        return *ports[idx];
-    }
-}
-
-PhysicalMemory::MemoryPort::MemoryPort(const std::string &_name,
-                                       PhysicalMemory *_memory)
-    : SimpleTimingPort(_name, _memory), memory(_memory)
-{ }
-
-AddrRangeList
-PhysicalMemory::MemoryPort::getAddrRanges()
-{
-    return memory->getAddrRanges();
+    // either matched the cache or found in the tree
+    return true;
 }
 
 AddrRangeList
-PhysicalMemory::getAddrRanges()
+PhysicalMemory::getConfAddrRanges() const
 {
+    // this could be done once in the constructor, but since it is unlikely to
+    // be called more than once the iteration should not be a problem
     AddrRangeList ranges;
-    ranges.push_back(RangeSize(start(), size()));
-    return ranges;
-}
-
-unsigned
-PhysicalMemory::MemoryPort::deviceBlockSize() const
-{
-    return memory->deviceBlockSize();
-}
-
-Tick
-PhysicalMemory::MemoryPort::recvAtomic(PacketPtr pkt)
-{
-    return memory->doAtomicAccess(pkt);
-}
-
-void
-PhysicalMemory::MemoryPort::recvFunctional(PacketPtr pkt)
-{
-    pkt->pushLabel(memory->name());
-
-    if (!queue.checkFunctional(pkt)) {
-        // Default implementation of SimpleTimingPort::recvFunctional()
-        // calls recvAtomic() and throws away the latency; we can save a
-        // little here by just not calculating the latency.
-        memory->doFunctionalAccess(pkt);
-    }
-
-    pkt->popLabel();
-}
-
-unsigned int
-PhysicalMemory::drain(Event *de)
-{
-    int count = 0;
-    for (PortIterator pi = ports.begin(); pi != ports.end(); ++pi) {
-        count += (*pi)->drain(de);
+    for (vector<AbstractMemory*>::const_iterator m = memories.begin();
+         m != memories.end(); ++m) {
+        if ((*m)->isConfReported()) {
+            ranges.push_back((*m)->getAddrRange());
+        }
     }
 
-    if (count)
-        changeState(Draining);
-    else
-        changeState(Drained);
-    return count;
+    return ranges;
 }
 
 void
-PhysicalMemory::serialize(ostream &os)
+PhysicalMemory::access(PacketPtr pkt)
 {
-    if (!pmemAddr)
-        return;
-
-    gzFile compressedMem;
-    string filename = name() + ".physmem";
-
-    SERIALIZE_SCALAR(filename);
-    SERIALIZE_SCALAR(_size);
-
-    // write memory file
-    string thefile = Checkpoint::dir() + "/" + filename.c_str();
-    int fd = creat(thefile.c_str(), 0664);
-    if (fd < 0) {
-        perror("creat");
-        fatal("Can't open physical memory checkpoint file '%s'\n", filename);
-    }
-
-    compressedMem = gzdopen(fd, "wb");
-    if (compressedMem == NULL)
-        fatal("Insufficient memory to allocate compression state for %s\n",
-                filename);
-
-    if (gzwrite(compressedMem, pmemAddr, size()) != (int)size()) {
-        fatal("Write failed on physical memory checkpoint file '%s'\n",
-              filename);
-    }
-
-    if (gzclose(compressedMem))
-        fatal("Close failed on physical memory checkpoint file '%s'\n",
-              filename);
-
-    list<LockedAddr>::iterator i = lockedAddrList.begin();
-
-    vector<Addr> lal_addr;
-    vector<int> lal_cid;
-    while (i != lockedAddrList.end()) {
-        lal_addr.push_back(i->addr);
-        lal_cid.push_back(i->contextId);
-        i++;
-    }
-    arrayParamOut(os, "lal_addr", lal_addr);
-    arrayParamOut(os, "lal_cid", lal_cid);
+    assert(pkt->isRequest());
+    Addr addr = pkt->getAddr();
+    range_map<Addr, AbstractMemory*>::const_iterator m = addrMap.find(addr);
+    assert(m != addrMap.end());
+    m->second->access(pkt);
 }
 
 void
-PhysicalMemory::unserialize(Checkpoint *cp, const string &section)
-{
-    if (!pmemAddr)
-        return;
-
-    gzFile compressedMem;
-    long *tempPage;
-    long *pmem_current;
-    uint64_t curSize;
-    uint32_t bytesRead;
-    const uint32_t chunkSize = 16384;
-
-    string filename;
-
-    UNSERIALIZE_SCALAR(filename);
-
-    filename = cp->cptDir + "/" + filename;
-
-    // mmap memoryfile
-    int fd = open(filename.c_str(), O_RDONLY);
-    if (fd < 0) {
-        perror("open");
-        fatal("Can't open physical memory checkpoint file '%s'", filename);
-    }
-
-    compressedMem = gzdopen(fd, "rb");
-    if (compressedMem == NULL)
-        fatal("Insufficient memory to allocate compression state for %s\n",
-                filename);
-
-    // unmap file that was mmapped in the constructor
-    // This is done here to make sure that gzip and open don't muck with our
-    // nice large space of memory before we reallocate it
-    munmap((char*)pmemAddr, size());
-
-    UNSERIALIZE_SCALAR(_size);
-    if (size() > params()->range.size())
-        fatal("Memory size has changed! size %lld, param size %lld\n",
-              size(), params()->range.size());
-
-    pmemAddr = (uint8_t *)mmap(NULL, size(),
-        PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
-
-    if (pmemAddr == (void *)MAP_FAILED) {
-        perror("mmap");
-        fatal("Could not mmap physical memory!\n");
-    }
-
-    curSize = 0;
-    tempPage = (long*)malloc(chunkSize);
-    if (tempPage == NULL)
-        fatal("Unable to malloc memory to read file %s\n", filename);
-
-    /* Only copy bytes that are non-zero, so we don't give the VM system hell */
-    while (curSize < size()) {
-        bytesRead = gzread(compressedMem, tempPage, chunkSize);
-        if (bytesRead == 0)
-            break;
-
-        assert(bytesRead % sizeof(long) == 0);
-
-        for (uint32_t x = 0; x < bytesRead / sizeof(long); x++)
-        {
-             if (*(tempPage+x) != 0) {
-                 pmem_current = (long*)(pmemAddr + curSize + x * sizeof(long));
-                 *pmem_current = *(tempPage+x);
-             }
-        }
-        curSize += bytesRead;
-    }
-
-    free(tempPage);
-
-    if (gzclose(compressedMem))
-        fatal("Close failed on physical memory checkpoint file '%s'\n",
-              filename);
-
-    vector<Addr> lal_addr;
-    vector<int> lal_cid;
-    arrayParamIn(cp, section, "lal_addr", lal_addr);
-    arrayParamIn(cp, section, "lal_cid", lal_cid);
-    for(int i = 0; i < lal_addr.size(); i++)
-        lockedAddrList.push_front(LockedAddr(lal_addr[i], lal_cid[i]));
-}
-
-PhysicalMemory *
-PhysicalMemoryParams::create()
+PhysicalMemory::functionalAccess(PacketPtr pkt)
 {
-    return new PhysicalMemory(this);
+    assert(pkt->isRequest());
+    Addr addr = pkt->getAddr();
+    range_map<Addr, AbstractMemory*>::const_iterator m = addrMap.find(addr);
+    assert(m != addrMap.end());
+    m->second->functionalAccess(pkt);
 }
diff --git a/src/mem/physical.hh b/src/mem/physical.hh
index 23d4052fa..e78b1d2da 100644
--- a/src/mem/physical.hh
+++ b/src/mem/physical.hh
@@ -1,6 +1,15 @@
 /*
- * Copyright (c) 2001-2005 The Regents of The University of Michigan
- * All rights reserved.
+ * Copyright (c) 2012 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
@@ -25,195 +34,88 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- * Authors: Ron Dreslinski
- */
-
-/* @file
+ * Authors: Andreas Hansson
  */
 
 #ifndef __PHYSICAL_MEMORY_HH__
 #define __PHYSICAL_MEMORY_HH__
 
-#include <map>
-#include <string>
-
-#include "base/range.hh"
-#include "base/statistics.hh"
-#include "mem/mem_object.hh"
+#include "base/range_map.hh"
+#include "mem/abstract_mem.hh"
 #include "mem/packet.hh"
-#include "mem/tport.hh"
-#include "params/PhysicalMemory.hh"
-#include "sim/eventq.hh"
-#include "sim/stats.hh"
-
-//
-// Functional model for a contiguous block of physical memory. (i.e. RAM)
-//
-class PhysicalMemory : public MemObject
-{
-  protected:
-
-    class MemoryPort : public SimpleTimingPort
-    {
-        PhysicalMemory *memory;
-
-      public:
 
-        MemoryPort(const std::string &_name, PhysicalMemory *_memory);
-
-      protected:
+/**
+ * The physical memory encapsulates all memories in the system and
+ * provides basic functionality for accessing those memories without
+ * going through the memory system and interconnect.
+ */
+class PhysicalMemory
+{
 
-        virtual Tick recvAtomic(PacketPtr pkt);
+  private:
 
-        virtual void recvFunctional(PacketPtr pkt);
+    // Global address map
+    range_map<Addr, AbstractMemory* > addrMap;
 
-        virtual AddrRangeList getAddrRanges();
+    // a mutable cache for the last range that matched an address
+    mutable Range<Addr> rangeCache;
 
-        virtual unsigned deviceBlockSize() const;
-    };
+    // All address-mapped memories
+    std::vector<AbstractMemory*> memories;
 
-    int numPorts;
+    // The total memory size
+    uint64_t size;
 
+    // Prevent copying
+    PhysicalMemory(const PhysicalMemory&);
 
-  private:
-    // prevent copying of a MainMemory object
-    PhysicalMemory(const PhysicalMemory &specmem);
-    const PhysicalMemory &operator=(const PhysicalMemory &specmem);
-
-  protected:
-
-    class LockedAddr {
-      public:
-        // on alpha, minimum LL/SC granularity is 16 bytes, so lower
-        // bits need to masked off.
-        static const Addr Addr_Mask = 0xf;
-
-        static Addr mask(Addr paddr) { return (paddr & ~Addr_Mask); }
-
-        Addr addr;      // locked address
-        int contextId;     // locking hw context
-
-        // check for matching execution context
-        bool matchesContext(Request *req)
-        {
-            return (contextId == req->contextId());
-        }
-
-        LockedAddr(Request *req)
-            : addr(mask(req->getPaddr())),
-              contextId(req->contextId())
-        {
-        }
-        // constructor for unserialization use
-        LockedAddr(Addr _addr, int _cid)
-            : addr(_addr), contextId(_cid)
-        {
-        }
-    };
-
-    std::list<LockedAddr> lockedAddrList;
-
-    // helper function for checkLockedAddrs(): we really want to
-    // inline a quick check for an empty locked addr list (hopefully
-    // the common case), and do the full list search (if necessary) in
-    // this out-of-line function
-    bool checkLockedAddrList(PacketPtr pkt);
-
-    // Record the address of a load-locked operation so that we can
-    // clear the execution context's lock flag if a matching store is
-    // performed
-    void trackLoadLocked(PacketPtr pkt);
-
-    // Compare a store address with any locked addresses so we can
-    // clear the lock flag appropriately.  Return value set to 'false'
-    // if store operation should be suppressed (because it was a
-    // conditional store and the address was no longer locked by the
-    // requesting execution context), 'true' otherwise.  Note that
-    // this method must be called on *all* stores since even
-    // non-conditional stores must clear any matching lock addresses.
-    bool writeOK(PacketPtr pkt) {
-        Request *req = pkt->req;
-        if (lockedAddrList.empty()) {
-            // no locked addrs: nothing to check, store_conditional fails
-            bool isLLSC = pkt->isLLSC();
-            if (isLLSC) {
-                req->setExtraData(0);
-            }
-            return !isLLSC; // only do write if not an sc
-        } else {
-            // iterate over list...
-            return checkLockedAddrList(pkt);
-        }
-    }
-
-    uint8_t *pmemAddr;
-    Tick lat;
-    Tick lat_var;
-    std::vector<MemoryPort*> ports;
-    typedef std::vector<MemoryPort*>::iterator PortIterator;
-
-    uint64_t _size;
-    uint64_t _start;
-
-    /** Number of total bytes read from this memory */
-    Stats::Scalar bytesRead;
-    /** Number of instruction bytes read from this memory */
-    Stats::Scalar bytesInstRead;
-    /** Number of bytes written to this memory */
-    Stats::Scalar bytesWritten;
-    /** Number of read requests */
-    Stats::Scalar numReads;
-    /** Number of write requests */
-    Stats::Scalar numWrites;
-    /** Number of other requests */
-    Stats::Scalar numOther;
-    /** Read bandwidth from this memory */
-    Stats::Formula bwRead;
-    /** Read bandwidth from this memory */
-    Stats::Formula bwInstRead;
-    /** Write bandwidth from this memory */
-    Stats::Formula bwWrite;
-    /** Total bandwidth from this memory */
-    Stats::Formula bwTotal;
+    // Prevent assignment
+    PhysicalMemory& operator=(const PhysicalMemory&);
 
   public:
-    uint64_t size() { return _size; }
-    uint64_t start() { return _start; }
 
-  public:
-    typedef PhysicalMemoryParams Params;
-    PhysicalMemory(const Params *p);
-    virtual ~PhysicalMemory();
-
-    const Params *
-    params() const
-    {
-        return dynamic_cast<const Params *>(_params);
-    }
-
-  public:
-    unsigned deviceBlockSize() const;
-    AddrRangeList getAddrRanges();
-    virtual SlavePort &getSlavePort(const std::string &if_name, int idx = -1);
-    void virtual init();
-    unsigned int drain(Event *de);
+    /**
+     * Create a physical memory object, wrapping a number of memories.
+     */
+    PhysicalMemory(const std::vector<AbstractMemory*>& _memories);
 
-    Tick doAtomicAccess(PacketPtr pkt);
-    void doFunctionalAccess(PacketPtr pkt);
+    /**
+     * Nothing to destruct.
+     */
+    ~PhysicalMemory() { }
+
+    /**
+     * Check if a physical address is within a range of a memory that
+     * is part of the global address map.
+     *
+     * @param addr A physical address
+     * @return Whether the address corresponds to a memory
+     */
+    bool isMemAddr(Addr addr) const;
 
+    /**
+     * Get the memory ranges for all memories that are to be reported
+     * to the configuration table.
+     *
+     * @return All configuration table memory ranges
+     */
+    AddrRangeList getConfAddrRanges() const;
 
-  protected:
-    virtual Tick calculateLatency(PacketPtr pkt);
+    /**
+     * Get the total physical memory size.
+     *
+     * @return The sum of all memory sizes
+     */
+    uint64_t totalSize() const { return size; }
 
-  public:
-     /**
-     * Register Statistics
+    /**
+     *
      */
-    void regStats();
+    void access(PacketPtr pkt);
+    void functionalAccess(PacketPtr pkt);
+};
+
 
-    virtual void serialize(std::ostream &os);
-    virtual void unserialize(Checkpoint *cp, const std::string &section);
 
-};
 
 #endif //__PHYSICAL_MEMORY_HH__
diff --git a/src/mem/ruby/system/RubyPort.cc b/src/mem/ruby/system/RubyPort.cc
index 8fd68be7c..0cdb919b1 100644
--- a/src/mem/ruby/system/RubyPort.cc
+++ b/src/mem/ruby/system/RubyPort.cc
@@ -467,7 +467,7 @@ RubyPort::M5Port::recvFunctional(PacketPtr pkt)
         // The following command performs the real functional access.
         // This line should be removed once Ruby supplies the official version
         // of data.
-        ruby_port->system->physmem->doFunctionalAccess(pkt);
+        ruby_port->system->getPhysMem().functionalAccess(pkt);
     }
 
     // turn packet around to go back to requester if response expected
@@ -646,7 +646,7 @@ RubyPort::M5Port::hitCallback(PacketPtr pkt)
     DPRINTF(RubyPort, "Hit callback needs response %d\n", needsResponse);
 
     if (accessPhysMem) {
-        ruby_port->system->physmem->doAtomicAccess(pkt);
+        ruby_port->system->getPhysMem().access(pkt);
     } else if (needsResponse) {
         pkt->makeResponse();
     }
@@ -688,7 +688,7 @@ RubyPort::M5Port::getAddrRanges()
 bool
 RubyPort::M5Port::isPhysMemAddress(Addr addr)
 {
-    return ruby_port->system->isMemory(addr);
+    return ruby_port->system->isMemAddr(addr);
 }
 
 unsigned
diff --git a/src/mem/simple_mem.cc b/src/mem/simple_mem.cc
new file mode 100644
index 000000000..10e809d0b
--- /dev/null
+++ b/src/mem/simple_mem.cc
@@ -0,0 +1,167 @@
+/*
+ * Copyright (c) 2010-2012 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * Copyright (c) 2001-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Ron Dreslinski
+ *          Ali Saidi
+ *          Andreas Hansson
+ */
+
+#include "base/random.hh"
+#include "mem/simple_mem.hh"
+
+using namespace std;
+
+SimpleMemory::SimpleMemory(const Params* p) :
+    AbstractMemory(p),
+    lat(p->latency), lat_var(p->latency_var)
+{
+    for (size_t i = 0; i < p->port_port_connection_count; ++i) {
+        ports.push_back(new MemoryPort(csprintf("%s-port-%d", name(), i),
+                                       *this));
+    }
+}
+
+void
+SimpleMemory::init()
+{
+    for (vector<MemoryPort*>::iterator p = ports.begin(); p != ports.end();
+         ++p) {
+        if (!(*p)->isConnected()) {
+            fatal("SimpleMemory port %s is unconnected!\n", (*p)->name());
+        } else {
+            (*p)->sendRangeChange();
+        }
+    }
+}
+
+Tick
+SimpleMemory::calculateLatency(PacketPtr pkt)
+{
+    if (pkt->memInhibitAsserted()) {
+        return 0;
+    } else {
+        Tick latency = lat;
+        if (lat_var != 0)
+            latency += random_mt.random<Tick>(0, lat_var);
+        return latency;
+    }
+}
+
+Tick
+SimpleMemory::doAtomicAccess(PacketPtr pkt)
+{
+    access(pkt);
+    return calculateLatency(pkt);
+}
+
+void
+SimpleMemory::doFunctionalAccess(PacketPtr pkt)
+{
+    functionalAccess(pkt);
+}
+
+SlavePort &
+SimpleMemory::getSlavePort(const std::string &if_name, int idx)
+{
+    if (if_name != "port") {
+        return MemObject::getSlavePort(if_name, idx);
+    } else {
+        if (idx >= static_cast<int>(ports.size())) {
+            fatal("SimpleMemory::getSlavePort: unknown index %d\n", idx);
+        }
+
+        return *ports[idx];
+    }
+}
+
+unsigned int
+SimpleMemory::drain(Event *de)
+{
+    int count = 0;
+    for (vector<MemoryPort*>::iterator p = ports.begin(); p != ports.end();
+         ++p) {
+        count += (*p)->drain(de);
+    }
+
+    if (count)
+        changeState(Draining);
+    else
+        changeState(Drained);
+    return count;
+}
+
+SimpleMemory::MemoryPort::MemoryPort(const std::string& _name,
+                                     SimpleMemory& _memory)
+    : SimpleTimingPort(_name, &_memory), memory(_memory)
+{ }
+
+AddrRangeList
+SimpleMemory::MemoryPort::getAddrRanges()
+{
+    AddrRangeList ranges;
+    ranges.push_back(memory.getAddrRange());
+    return ranges;
+}
+
+Tick
+SimpleMemory::MemoryPort::recvAtomic(PacketPtr pkt)
+{
+    return memory.doAtomicAccess(pkt);
+}
+
+void
+SimpleMemory::MemoryPort::recvFunctional(PacketPtr pkt)
+{
+    pkt->pushLabel(memory.name());
+
+    if (!queue.checkFunctional(pkt)) {
+        // Default implementation of SimpleTimingPort::recvFunctional()
+        // calls recvAtomic() and throws away the latency; we can save a
+        // little here by just not calculating the latency.
+        memory.doFunctionalAccess(pkt);
+    }
+
+    pkt->popLabel();
+}
+
+SimpleMemory*
+SimpleMemoryParams::create()
+{
+    return new SimpleMemory(this);
+}
diff --git a/src/mem/simple_mem.hh b/src/mem/simple_mem.hh
new file mode 100644
index 000000000..b21b38fd8
--- /dev/null
+++ b/src/mem/simple_mem.hh
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2012 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * Copyright (c) 2001-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Ron Dreslinski
+ *          Andreas Hansson
+ */
+
+/**
+ * @file
+ * SimpleMemory declaration
+ */
+
+#ifndef __SIMPLE_MEMORY_HH__
+#define __SIMPLE_MEMORY_HH__
+
+#include "mem/abstract_mem.hh"
+#include "mem/tport.hh"
+#include "params/SimpleMemory.hh"
+
+/**
+ * The simple memory is a basic multi-ported memory with an infinite
+ * throughput and a fixed latency, potentially with a variance added
+ * to it. It uses a SimpleTimingPort to implement the timing accesses.
+ */
+class SimpleMemory : public AbstractMemory
+{
+
+  private:
+
+    class MemoryPort : public SimpleTimingPort
+    {
+        SimpleMemory& memory;
+
+      public:
+
+        MemoryPort(const std::string& _name, SimpleMemory& _memory);
+
+      protected:
+
+        virtual Tick recvAtomic(PacketPtr pkt);
+
+        virtual void recvFunctional(PacketPtr pkt);
+
+        virtual AddrRangeList getAddrRanges();
+
+    };
+
+    std::vector<MemoryPort*> ports;
+
+    Tick lat;
+    Tick lat_var;
+
+  public:
+
+    typedef SimpleMemoryParams Params;
+    SimpleMemory(const Params *p);
+    virtual ~SimpleMemory() { }
+
+    unsigned int drain(Event* de);
+
+    virtual SlavePort& getSlavePort(const std::string& if_name, int idx = -1);
+    virtual void init();
+
+    const Params *
+    params() const
+    {
+        return dynamic_cast<const Params *>(_params);
+    }
+
+  protected:
+
+    Tick doAtomicAccess(PacketPtr pkt);
+    void doFunctionalAccess(PacketPtr pkt);
+    virtual Tick calculateLatency(PacketPtr pkt);
+
+};
+
+#endif //__SIMPLE_MEMORY_HH__