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diff --git a/src/mem/qos/turnaround_policy_ideal.cc b/src/mem/qos/turnaround_policy_ideal.cc
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+++ b/src/mem/qos/turnaround_policy_ideal.cc
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+/*
+ * Copyright (c) 2018 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
+ * 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: Matteo Andreozzi
+ */
+
+#include "turnaround_policy_ideal.hh"
+
+#include "params/QoSTurnaroundPolicyIdeal.hh"
+
+namespace QoS {
+
+TurnaroundPolicyIdeal::TurnaroundPolicyIdeal(const Params* p)
+  : TurnaroundPolicy(p)
+{}
+
+TurnaroundPolicyIdeal::~TurnaroundPolicyIdeal()
+{}
+
+MemCtrl::BusState
+TurnaroundPolicyIdeal::selectBusState()
+{
+    auto bus_state = memCtrl->getBusState();
+    const auto num_priorities = memCtrl->numPriorities();
+
+    // QoS-aware turnaround policy
+    // Loop for every queue in the memory controller.
+    for (uint8_t i = 0; i < num_priorities; i++) {
+
+        // Starting from top priority queues first
+        uint8_t queue_idx = num_priorities - i - 1;
+
+        const uint64_t readq_size = memCtrl->getReadQueueSize(queue_idx);
+        const uint64_t writeq_size = memCtrl->getWriteQueueSize(queue_idx);
+
+        // No data for current priority: both the read queue
+        // and write queue are empty.
+        if ((readq_size == 0) && (writeq_size == 0)) {
+            continue;
+        }
+
+        // Data found - select state
+        if (readq_size == 0) {
+            bus_state = MemCtrl::WRITE;
+        } else if (writeq_size == 0) {
+            bus_state = MemCtrl::READ;
+        } else {
+            // readq_size > 0 && writeq_size > 0
+            bus_state = ((memCtrl->getBusState() == MemCtrl::READ) ?
+                    MemCtrl::WRITE : MemCtrl::READ);
+        }
+
+        DPRINTF(QOS,
+                "QoSMemoryTurnaround::QoSTurnaroundPolicyIdeal - "
+                "QoS priority %d queues %d, %d triggering bus %s "
+                "in state %s\n", queue_idx, readq_size, writeq_size,
+                (bus_state != memCtrl->getBusState()) ?
+                "turnaround" : "staying",
+                (bus_state == MemCtrl::READ)? "READ" : "WRITE");
+        // State selected - exit loop
+        break;
+    }
+
+    return bus_state;
+}
+
+} // namespace QoS
+
+QoS::TurnaroundPolicyIdeal *
+QoSTurnaroundPolicyIdealParams::create()
+{
+    return new QoS::TurnaroundPolicyIdeal(this);
+}