clocked_object.hh revision 9180
19157Sandreas.hansson@arm.com/* 29157Sandreas.hansson@arm.com * Copyright (c) 2012 ARM Limited 39157Sandreas.hansson@arm.com * All rights reserved 49157Sandreas.hansson@arm.com * 59157Sandreas.hansson@arm.com * The license below extends only to copyright in the software and shall 69157Sandreas.hansson@arm.com * not be construed as granting a license to any other intellectual 79157Sandreas.hansson@arm.com * property including but not limited to intellectual property relating 89157Sandreas.hansson@arm.com * to a hardware implementation of the functionality of the software 99157Sandreas.hansson@arm.com * licensed hereunder. You may use the software subject to the license 109157Sandreas.hansson@arm.com * terms below provided that you ensure that this notice is replicated 119157Sandreas.hansson@arm.com * unmodified and in its entirety in all distributions of the software, 129157Sandreas.hansson@arm.com * modified or unmodified, in source code or in binary form. 139157Sandreas.hansson@arm.com * 149157Sandreas.hansson@arm.com * Redistribution and use in source and binary forms, with or without 159157Sandreas.hansson@arm.com * modification, are permitted provided that the following conditions are 169157Sandreas.hansson@arm.com * met: redistributions of source code must retain the above copyright 179157Sandreas.hansson@arm.com * notice, this list of conditions and the following disclaimer; 189157Sandreas.hansson@arm.com * redistributions in binary form must reproduce the above copyright 199157Sandreas.hansson@arm.com * notice, this list of conditions and the following disclaimer in the 209157Sandreas.hansson@arm.com * documentation and/or other materials provided with the distribution; 219157Sandreas.hansson@arm.com * neither the name of the copyright holders nor the names of its 229157Sandreas.hansson@arm.com * contributors may be used to endorse or promote products derived from 239157Sandreas.hansson@arm.com * this software without specific prior written permission. 249157Sandreas.hansson@arm.com * 259157Sandreas.hansson@arm.com * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 269157Sandreas.hansson@arm.com * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 279157Sandreas.hansson@arm.com * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 289157Sandreas.hansson@arm.com * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 299157Sandreas.hansson@arm.com * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 309157Sandreas.hansson@arm.com * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 319157Sandreas.hansson@arm.com * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 329157Sandreas.hansson@arm.com * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 339157Sandreas.hansson@arm.com * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 349157Sandreas.hansson@arm.com * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 359157Sandreas.hansson@arm.com * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 369157Sandreas.hansson@arm.com * 379157Sandreas.hansson@arm.com * Authors: Andreas Hansson 389157Sandreas.hansson@arm.com */ 399157Sandreas.hansson@arm.com 409157Sandreas.hansson@arm.com/** 419157Sandreas.hansson@arm.com * @file 429157Sandreas.hansson@arm.com * ClockedObject declaration and implementation. 439157Sandreas.hansson@arm.com */ 449157Sandreas.hansson@arm.com 459157Sandreas.hansson@arm.com#ifndef __SIM_CLOCKED_OBJECT_HH__ 469157Sandreas.hansson@arm.com#define __SIM_CLOCKED_OBJECT_HH__ 479157Sandreas.hansson@arm.com 489157Sandreas.hansson@arm.com#include "base/intmath.hh" 499157Sandreas.hansson@arm.com#include "params/ClockedObject.hh" 509157Sandreas.hansson@arm.com#include "sim/sim_object.hh" 519157Sandreas.hansson@arm.com 529157Sandreas.hansson@arm.com/** 539157Sandreas.hansson@arm.com * The ClockedObject class extends the SimObject with a clock and 549157Sandreas.hansson@arm.com * accessor functions to relate ticks to the cycles of the object. 559157Sandreas.hansson@arm.com */ 569157Sandreas.hansson@arm.comclass ClockedObject : public SimObject 579157Sandreas.hansson@arm.com{ 589157Sandreas.hansson@arm.com 599157Sandreas.hansson@arm.com private: 609157Sandreas.hansson@arm.com 619179Sandreas.hansson@arm.com // the tick value of the next clock edge (>= curTick()) at the 629179Sandreas.hansson@arm.com // time of the last call to update() 639179Sandreas.hansson@arm.com mutable Tick tick; 649179Sandreas.hansson@arm.com 659179Sandreas.hansson@arm.com // The cycle counter value corresponding to the current value of 669179Sandreas.hansson@arm.com // 'tick' 679180Sandreas.hansson@arm.com mutable Cycles cycle; 689179Sandreas.hansson@arm.com 699157Sandreas.hansson@arm.com /** 709157Sandreas.hansson@arm.com * Prevent inadvertent use of the copy constructor and assignment 719157Sandreas.hansson@arm.com * operator by making them private. 729157Sandreas.hansson@arm.com */ 739157Sandreas.hansson@arm.com ClockedObject(ClockedObject&); 749157Sandreas.hansson@arm.com ClockedObject& operator=(ClockedObject&); 759157Sandreas.hansson@arm.com 769179Sandreas.hansson@arm.com /** 779179Sandreas.hansson@arm.com * Align cycle and tick to the next clock edge if not already done. 789179Sandreas.hansson@arm.com */ 799179Sandreas.hansson@arm.com void update() const 809179Sandreas.hansson@arm.com { 819179Sandreas.hansson@arm.com // both tick and cycle are up-to-date and we are done, note 829179Sandreas.hansson@arm.com // that the >= is important as it captures cases where tick 839179Sandreas.hansson@arm.com // has already passed curTick() 849179Sandreas.hansson@arm.com if (tick >= curTick()) 859179Sandreas.hansson@arm.com return; 869179Sandreas.hansson@arm.com 879179Sandreas.hansson@arm.com // optimise for the common case and see if the tick should be 889179Sandreas.hansson@arm.com // advanced by a single clock period 899179Sandreas.hansson@arm.com tick += clock; 909179Sandreas.hansson@arm.com ++cycle; 919179Sandreas.hansson@arm.com 929179Sandreas.hansson@arm.com // see if we are done at this point 939179Sandreas.hansson@arm.com if (tick >= curTick()) 949179Sandreas.hansson@arm.com return; 959179Sandreas.hansson@arm.com 969179Sandreas.hansson@arm.com // if not, we have to recalculate the cycle and tick, we 979179Sandreas.hansson@arm.com // perform the calculations in terms of relative cycles to 989179Sandreas.hansson@arm.com // allow changes to the clock period in the future 999180Sandreas.hansson@arm.com Cycles elapsedCycles(divCeil(curTick() - tick, clock)); 1009179Sandreas.hansson@arm.com cycle += elapsedCycles; 1019179Sandreas.hansson@arm.com tick += elapsedCycles * clock; 1029179Sandreas.hansson@arm.com } 1039179Sandreas.hansson@arm.com 1049157Sandreas.hansson@arm.com protected: 1059157Sandreas.hansson@arm.com 1069157Sandreas.hansson@arm.com // Clock period in ticks 1079157Sandreas.hansson@arm.com Tick clock; 1089157Sandreas.hansson@arm.com 1099157Sandreas.hansson@arm.com /** 1109157Sandreas.hansson@arm.com * Create a clocked object and set the clock based on the 1119157Sandreas.hansson@arm.com * parameters. 1129157Sandreas.hansson@arm.com */ 1139179Sandreas.hansson@arm.com ClockedObject(const ClockedObjectParams* p) : 1149179Sandreas.hansson@arm.com SimObject(p), tick(0), cycle(0), clock(p->clock) 1159157Sandreas.hansson@arm.com { } 1169157Sandreas.hansson@arm.com 1179157Sandreas.hansson@arm.com /** 1189157Sandreas.hansson@arm.com * Virtual destructor due to inheritance. 1199157Sandreas.hansson@arm.com */ 1209157Sandreas.hansson@arm.com virtual ~ClockedObject() { } 1219157Sandreas.hansson@arm.com 1229157Sandreas.hansson@arm.com public: 1239157Sandreas.hansson@arm.com 1249157Sandreas.hansson@arm.com /** 1259179Sandreas.hansson@arm.com * Determine the tick when a cycle begins, by default the current 1269179Sandreas.hansson@arm.com * one, but the argument also enables the caller to determine a 1279179Sandreas.hansson@arm.com * future cycle. 1289179Sandreas.hansson@arm.com * 1299179Sandreas.hansson@arm.com * @param cycles The number of cycles into the future 1309179Sandreas.hansson@arm.com * 1319179Sandreas.hansson@arm.com * @return The tick when the clock edge occurs 1329179Sandreas.hansson@arm.com */ 1339180Sandreas.hansson@arm.com inline Tick clockEdge(Cycles cycles = Cycles(0)) const 1349179Sandreas.hansson@arm.com { 1359179Sandreas.hansson@arm.com // align tick to the next clock edge 1369179Sandreas.hansson@arm.com update(); 1379179Sandreas.hansson@arm.com 1389179Sandreas.hansson@arm.com // figure out when this future cycle is 1399180Sandreas.hansson@arm.com return tick + clock * cycles; 1409179Sandreas.hansson@arm.com } 1419179Sandreas.hansson@arm.com 1429179Sandreas.hansson@arm.com /** 1439179Sandreas.hansson@arm.com * Determine the current cycle, corresponding to a tick aligned to 1449179Sandreas.hansson@arm.com * a clock edge. 1459179Sandreas.hansson@arm.com * 1469180Sandreas.hansson@arm.com * @return The current cycle count 1479179Sandreas.hansson@arm.com */ 1489180Sandreas.hansson@arm.com inline Cycles curCycle() const 1499179Sandreas.hansson@arm.com { 1509179Sandreas.hansson@arm.com // align cycle to the next clock edge. 1519179Sandreas.hansson@arm.com update(); 1529179Sandreas.hansson@arm.com 1539179Sandreas.hansson@arm.com return cycle; 1549179Sandreas.hansson@arm.com } 1559179Sandreas.hansson@arm.com 1569179Sandreas.hansson@arm.com /** 1579157Sandreas.hansson@arm.com * Based on the clock of the object, determine the tick when the 1589179Sandreas.hansson@arm.com * next cycle begins, in other words, return the next clock edge. 1599157Sandreas.hansson@arm.com * 1609157Sandreas.hansson@arm.com * @return The tick when the next cycle starts 1619157Sandreas.hansson@arm.com */ 1629157Sandreas.hansson@arm.com Tick nextCycle() const 1639179Sandreas.hansson@arm.com { return clockEdge(); } 1649157Sandreas.hansson@arm.com 1659180Sandreas.hansson@arm.com inline uint64_t frequency() const { return SimClock::Frequency / clock; } 1669157Sandreas.hansson@arm.com 1679179Sandreas.hansson@arm.com inline Tick clockPeriod() const { return clock; } 1689157Sandreas.hansson@arm.com 1699180Sandreas.hansson@arm.com inline Cycles ticksToCycles(Tick tick) const 1709180Sandreas.hansson@arm.com { return Cycles(tick / clock); } 1719157Sandreas.hansson@arm.com 1729157Sandreas.hansson@arm.com}; 1739157Sandreas.hansson@arm.com 1749157Sandreas.hansson@arm.com#endif //__SIM_CLOCKED_OBJECT_HH__ 175