src/mem/qos/policy.hh

   1 /*
   2  * Copyright (c) 2018 ARM Limited
   3  * All rights reserved
   4  *
   5  * The license below extends only to copyright in the software and shall
   6  * not be construed as granting a license to any other intellectual
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   8  * to a hardware implementation of the functionality of the software
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  10  * terms below provided that you ensure that this notice is replicated
  11  * unmodified and in its entirety in all distributions of the software,
  12  * modified or unmodified, in source code or in binary form.
  13  *
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  15  * modification, are permitted provided that the following conditions are
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  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  * Author: Matteo Andreozzi
  38  */
  39
  40 #ifndef __MEM_QOS_POLICY_HH__
  41 #define __MEM_QOS_POLICY_HH__
  42
  43 #include "base/trace.hh"
  44 #include "debug/QOS.hh"
  45 #include "mem/qos/mem_ctrl.hh"
  46 #include "mem/packet.hh"
  47 #include "sim/system.hh"
  48
  49 namespace QoS {
  50
  51 /**
  52  * QoS Policy base class
  53  *
  54  * QoS Policy base class: all QoS policies derive from this class to
  55  * implement specific QoS scheduling algorithms
  56  *
  57  */
  58 class Policy : public SimObject
  59 {
  60   public:
  61     using Params = QoSPolicyParams;
  62     Policy(const Params* p);
  63
  64     virtual ~Policy();
  65
  66     virtual void regStats() override {};
  67
  68     virtual void init() override {};
  69
  70     /**
  71      * Setting a pointer to the Memory Controller implementing
  72      * the policy.
  73      */
  74     void setMemCtrl(MemCtrl* mem) { memCtrl = mem; };
  75
  76     /**
  77      * Builds a MasterID/value pair given a master input.
  78      * This will be lookuped in the system list of masters in order
  79      * to retrieve the associated MasterID.
  80      * In case the master name/object cannot be resolved, the pairing
  81      * method will panic.
  82      *
  83      * @param master Master to lookup in the system
  84      * @param value Value to be associated with the MasterID
  85      * @return A MasterID/Value pair.
  86      */
  87     template <typename M, typename T>
  88     std::pair<MasterID, T> pair(M master, T value);
  89
  90     /**
  91      * Schedules data - must be defined by derived class
  92      *
  93      * @param mId master id to schedule
  94      * @param data data to schedule
  95      * @return QoS priority value
  96      */
  97     virtual uint8_t schedule(const MasterID mId, const uint64_t data) = 0;
  98
  99     /**
 100      * Schedules a packet. Non virtual interface for the scheduling
 101      * method requiring a master ID.
 102      *
 103      * @param pkt pointer to packet to schedule
 104      * @return QoS priority value
 105      */
 106     uint8_t schedule(const PacketPtr pkt);
 107
 108   protected:
 109     /** Pointer to parent memory controller implementing the policy */
 110     MemCtrl* memCtrl;
 111 };
 112
 113 template <typename M, typename T>
 114 std::pair<MasterID, T>
 115 Policy::pair(M master, T value)
 116 {
 117     auto id = memCtrl->system()->lookupMasterId(master);
 118
 119     panic_if(id == Request::invldMasterId,
 120              "Unable to find master %s\n", master);
 121
 122     DPRINTF(QOS,
 123             "Master %s [id %d] associated with QoS data %d\n",
 124             master, id, value);
 125
 126     return std::pair<MasterID, T>(id, value);
 127 }
 128
 129 } // namespace QoS
 130
 131 #endif /* __MEM_QOS_POLICY_HH__ */