ruby: Add support for address ranges in the directory

Previously the directory covered a flat address range that always
started from address 0. This change adds a vector of address ranges
with interleaving and hashing that each directory keeps track of and
the necessary flexibility to support systems with non continuous
memory ranges.

Change-Id: I6ea1c629bdf4c5137b7d9c89dbaf6c826adfd977
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2903
Reviewed-by: Bradford Beckmann <brad.beckmann@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

3 files changed, 74 insertions, 55 deletions

diff --git a/src/mem/ruby/structures/DirectoryMemory.cc b/src/mem/ruby/structures/DirectoryMemory.cc
index ee77931d7..551e3f57f 100644
--- a/src/mem/ruby/structures/DirectoryMemory.cc
+++ b/src/mem/ruby/structures/DirectoryMemory.cc
@@ -1,4 +1,16 @@
 /*
+ * Copyright (c) 2017 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) 1999-2008 Mark D. Hill and David A. Wood
  * Copyright (c) 2017 Google Inc.
  * All rights reserved.
@@ -31,6 +43,7 @@
 
 #include "mem/ruby/structures/DirectoryMemory.hh"
 
+#include "base/addr_range.hh"
 #include "base/intmath.hh"
 #include "debug/RubyCache.hh"
 #include "debug/RubyStats.hh"
@@ -40,25 +53,15 @@
 
 using namespace std;
 
-int DirectoryMemory::m_num_directories = 0;
-int DirectoryMemory::m_num_directories_bits = 0;
-int DirectoryMemory::m_numa_high_bit = 0;
-
 DirectoryMemory::DirectoryMemory(const Params *p)
-    : SimObject(p)
+    : SimObject(p), addrRanges(p->addr_ranges.begin(), p->addr_ranges.end())
 {
-    m_version = p->version;
-    // In X86, there is an IO gap in the 3-4GB range.
-    if (p->system->getArch() == Arch::X86ISA && p->size > 0xc0000000){
-        // We need to add 1GB to the size for the gap
-        m_size_bytes = p->size + 0x40000000;
-    }
-    else {
-        m_size_bytes = p->size;
+    m_size_bytes = 0;
+    for (const auto &r: addrRanges) {
+        m_size_bytes += r.size();
     }
     m_size_bits = floorLog2(m_size_bytes);
     m_num_entries = 0;
-    m_numa_high_bit = p->numa_high_bit;
 }
 
 void
@@ -68,14 +71,6 @@ DirectoryMemory::init()
     m_entries = new AbstractEntry*[m_num_entries];
     for (int i = 0; i < m_num_entries; i++)
         m_entries[i] = NULL;
-
-    m_num_directories++;
-    m_num_directories_bits = ceilLog2(m_num_directories);
-
-    if (m_numa_high_bit == 0) {
-        m_numa_high_bit = RubySystem::getMemorySizeBits() - 1;
-    }
-    assert(m_numa_high_bit != 0);
 }
 
 DirectoryMemory::~DirectoryMemory()
@@ -89,37 +84,29 @@ DirectoryMemory::~DirectoryMemory()
     delete [] m_entries;
 }
 
-uint64_t
-DirectoryMemory::mapAddressToDirectoryVersion(Addr address)
-{
-    if (m_num_directories_bits == 0)
-        return 0;
-
-    uint64_t ret = bitSelect(address,
-                           m_numa_high_bit - m_num_directories_bits + 1,
-                           m_numa_high_bit);
-    return ret;
-}
-
 bool
 DirectoryMemory::isPresent(Addr address)
 {
-    bool ret = (mapAddressToDirectoryVersion(address) == m_version);
-    return ret;
+    for (const auto& r: addrRanges) {
+        if (r.contains(address)) {
+            return true;
+        }
+    }
+    return false;
 }
 
 uint64_t
 DirectoryMemory::mapAddressToLocalIdx(Addr address)
 {
-    uint64_t ret;
-    if (m_num_directories_bits > 0) {
-        ret = bitRemove(address, m_numa_high_bit - m_num_directories_bits + 1,
-                        m_numa_high_bit);
-    } else {
-        ret = address;
+    uint64_t ret = 0;
+    for (const auto& r: addrRanges) {
+        if (r.contains(address)) {
+            ret += r.getOffset(address);
+            break;
+        }
+        ret += r.size();
     }
-
-    return ret >> (RubySystem::getBlockSizeBits());
+    return ret >> RubySystem::getBlockSizeBits();
 }
 
 AbstractEntry*
diff --git a/src/mem/ruby/structures/DirectoryMemory.hh b/src/mem/ruby/structures/DirectoryMemory.hh
index 98403808b..36defd5e9 100644
--- a/src/mem/ruby/structures/DirectoryMemory.hh
+++ b/src/mem/ruby/structures/DirectoryMemory.hh
@@ -1,4 +1,16 @@
 /*
+ * Copyright (c) 2017 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) 1999-2008 Mark D. Hill and David A. Wood
  * All rights reserved.
  *
@@ -32,6 +44,7 @@
 #include <iostream>
 #include <string>
 
+#include "base/addr_range.hh"
 #include "mem/protocol/DirectoryRequestType.hh"
 #include "mem/ruby/common/Address.hh"
 #include "mem/ruby/slicc_interface/AbstractEntry.hh"
@@ -47,8 +60,18 @@ class DirectoryMemory : public SimObject
 
     void init();
 
+    /**
+     * Return the index in the directory based on an address
+     *
+     * This function transforms an address which belongs to a not
+     * necessarily continuous vector of address ranges into a flat
+     * address that we use to index in the directory
+     *
+     * @param an input address
+     * @return the corresponding index in the directory
+     *
+     */
     uint64_t mapAddressToLocalIdx(Addr address);
-    static uint64_t mapAddressToDirectoryVersion(Addr address);
 
     uint64_t getSize() { return m_size_bytes; }
 
@@ -72,11 +95,12 @@ class DirectoryMemory : public SimObject
     uint64_t m_size_bytes;
     uint64_t m_size_bits;
     uint64_t m_num_entries;
-    int m_version;
 
-    static int m_num_directories;
-    static int m_num_directories_bits;
-    static int m_numa_high_bit;
+    /**
+     * The address range for which the directory responds. Normally
+     * this is all possible memory addresses.
+     */
+    const AddrRangeList addrRanges;
 };
 
 inline std::ostream&
diff --git a/src/mem/ruby/structures/DirectoryMemory.py b/src/mem/ruby/structures/DirectoryMemory.py
index 2518380b2..ab9c7235f 100644
--- a/src/mem/ruby/structures/DirectoryMemory.py
+++ b/src/mem/ruby/structures/DirectoryMemory.py
@@ -1,3 +1,15 @@
+# Copyright (c) 2017 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) 2009 Advanced Micro Devices, Inc.
 # All rights reserved.
 #
@@ -35,9 +47,5 @@ class RubyDirectoryMemory(SimObject):
     type = 'RubyDirectoryMemory'
     cxx_class = 'DirectoryMemory'
     cxx_header = "mem/ruby/structures/DirectoryMemory.hh"
-    version = Param.Int(0, "")
-    size = Param.MemorySize("1GB", "capacity in bytes")
-    # the default value of the numa high bit is specified in the command line
-    # option and must be passed into the directory memory sim object
-    numa_high_bit = Param.Int("numa high bit")
-    system = Param.System(Parent.any, "system object")
+    addr_ranges = VectorParam.AddrRange(
+        Parent.addr_ranges, "Address range this directory responds to")