clocked_object.hh revision 9545:508784fad4e5
12330SN/A/* 29426SAndreas.Sandberg@ARM.com * Copyright (c) 2012 ARM Limited 39920Syasuko.eckert@amd.com * All rights reserved 48733Sgeoffrey.blake@arm.com * 58733Sgeoffrey.blake@arm.com * The license below extends only to copyright in the software and shall 68733Sgeoffrey.blake@arm.com * not be construed as granting a license to any other intellectual 78733Sgeoffrey.blake@arm.com * property including but not limited to intellectual property relating 88733Sgeoffrey.blake@arm.com * to a hardware implementation of the functionality of the software 98733Sgeoffrey.blake@arm.com * licensed hereunder. You may use the software subject to the license 108733Sgeoffrey.blake@arm.com * terms below provided that you ensure that this notice is replicated 118733Sgeoffrey.blake@arm.com * unmodified and in its entirety in all distributions of the software, 128733Sgeoffrey.blake@arm.com * modified or unmodified, in source code or in binary form. 138733Sgeoffrey.blake@arm.com * 148733Sgeoffrey.blake@arm.com * Redistribution and use in source and binary forms, with or without 152330SN/A * modification, are permitted provided that the following conditions are 162330SN/A * met: redistributions of source code must retain the above copyright 172330SN/A * notice, this list of conditions and the following disclaimer; 182330SN/A * redistributions in binary form must reproduce the above copyright 192330SN/A * notice, this list of conditions and the following disclaimer in the 202330SN/A * documentation and/or other materials provided with the distribution; 212330SN/A * neither the name of the copyright holders nor the names of its 222330SN/A * contributors may be used to endorse or promote products derived from 232330SN/A * this software without specific prior written permission. 242330SN/A * 252330SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 262330SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 272330SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 282330SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 292330SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 302330SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 312330SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 322330SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 332330SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 342330SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 352330SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 362330SN/A * 372330SN/A * Authors: Andreas Hansson 382330SN/A */ 392330SN/A 402689Sktlim@umich.edu/** 412689Sktlim@umich.edu * @file 422330SN/A * ClockedObject declaration and implementation. 432330SN/A */ 442683Sktlim@umich.edu 452683Sktlim@umich.edu#ifndef __SIM_CLOCKED_OBJECT_HH__ 462315SN/A#define __SIM_CLOCKED_OBJECT_HH__ 472972Sgblack@eecs.umich.edu 486658Snate@binkert.org#include "base/intmath.hh" 492315SN/A#include "base/misc.hh" 502683Sktlim@umich.edu#include "params/ClockedObject.hh" 512680SN/A#include "sim/core.hh" 528733Sgeoffrey.blake@arm.com#include "sim/sim_object.hh" 532315SN/A 542315SN/A/** 553548Sgblack@eecs.umich.edu * The ClockedObject class extends the SimObject with a clock and 563548Sgblack@eecs.umich.edu * accessor functions to relate ticks to the cycles of the object. 573548Sgblack@eecs.umich.edu */ 583548Sgblack@eecs.umich.educlass ClockedObject : public SimObject 599020Sgblack@eecs.umich.edu{ 602330SN/A 612315SN/A private: 622350SN/A 632680SN/A // the tick value of the next clock edge (>= curTick()) at the 642680SN/A // time of the last call to update() 652683Sktlim@umich.edu mutable Tick tick; 662683Sktlim@umich.edu 672683Sktlim@umich.edu // The cycle counter value corresponding to the current value of 682683Sktlim@umich.edu // 'tick' 692350SN/A mutable Cycles cycle; 702680SN/A 712680SN/A /** 722315SN/A * Prevent inadvertent use of the copy constructor and assignment 732315SN/A * operator by making them private. 742680SN/A */ 752683Sktlim@umich.edu ClockedObject(ClockedObject&); 762683Sktlim@umich.edu ClockedObject& operator=(ClockedObject&); 772330SN/A 782315SN/A /** 792315SN/A * Align cycle and tick to the next clock edge if not already done. 802315SN/A */ 812683Sktlim@umich.edu void update() const 822683Sktlim@umich.edu { 832680SN/A // both tick and cycle are up-to-date and we are done, note 842683Sktlim@umich.edu // that the >= is important as it captures cases where tick 852683Sktlim@umich.edu // has already passed curTick() 862683Sktlim@umich.edu if (tick >= curTick()) 872683Sktlim@umich.edu return; 882683Sktlim@umich.edu 892315SN/A // optimise for the common case and see if the tick should be 902315SN/A // advanced by a single clock period 912315SN/A tick += clock; 922315SN/A ++cycle; 932680SN/A 942315SN/A // see if we are done at this point 9510190Sakash.bagdia@arm.com if (tick >= curTick()) 9610190Sakash.bagdia@arm.com return; 9710110Sandreas.hansson@arm.com 988733Sgeoffrey.blake@arm.com // if not, we have to recalculate the cycle and tick, we 9911005Sandreas.sandberg@arm.com // perform the calculations in terms of relative cycles to 1008733Sgeoffrey.blake@arm.com // allow changes to the clock period in the future 10111005Sandreas.sandberg@arm.com Cycles elapsedCycles(divCeil(curTick() - tick, clock)); 1022315SN/A cycle += elapsedCycles; 1038733Sgeoffrey.blake@arm.com tick += elapsedCycles * clock; 1048733Sgeoffrey.blake@arm.com } 1052315SN/A 1062315SN/A // Clock period in ticks 1078733Sgeoffrey.blake@arm.com Tick clock; 10810110Sandreas.hansson@arm.com 1098733Sgeoffrey.blake@arm.com protected: 1108733Sgeoffrey.blake@arm.com 1118733Sgeoffrey.blake@arm.com /** 1128733Sgeoffrey.blake@arm.com * Create a clocked object and set the clock based on the 1138733Sgeoffrey.blake@arm.com * parameters. 1142315SN/A */ 1156022Sgblack@eecs.umich.edu ClockedObject(const ClockedObjectParams* p) : 1164997Sgblack@eecs.umich.edu SimObject(p), tick(0), cycle(0), clock(p->clock) 1176022Sgblack@eecs.umich.edu { 1184997Sgblack@eecs.umich.edu if (clock == 0) { 1198887Sgeoffrey.blake@arm.com fatal("%s has a clock period of zero\n", name()); 1208887Sgeoffrey.blake@arm.com } 1218887Sgeoffrey.blake@arm.com } 1228887Sgeoffrey.blake@arm.com 1238733Sgeoffrey.blake@arm.com /** 1249020Sgblack@eecs.umich.edu * Virtual destructor due to inheritance. 1258733Sgeoffrey.blake@arm.com */ 1262680SN/A virtual ~ClockedObject() { } 1272315SN/A 1283548Sgblack@eecs.umich.edu /** 1293548Sgblack@eecs.umich.edu * Reset the object's clock using the current global tick value. Likely 1302690Sktlim@umich.edu * to be used only when the global clock is reset. Currently, this done 1317679Sgblack@eecs.umich.edu * only when Ruby is done warming up the memory system. 1327679Sgblack@eecs.umich.edu */ 13311886Sbrandon.potter@amd.com void resetClock() const 13411886Sbrandon.potter@amd.com { 1358852Sandreas.hansson@arm.com Cycles elapsedCycles(divCeil(curTick(), clock)); 1362690Sktlim@umich.edu cycle = elapsedCycles; 1378852Sandreas.hansson@arm.com tick = elapsedCycles * clock; 1388706Sandreas.hansson@arm.com } 1398733Sgeoffrey.blake@arm.com 1408733Sgeoffrey.blake@arm.com public: 1418733Sgeoffrey.blake@arm.com 1428733Sgeoffrey.blake@arm.com /** 1438733Sgeoffrey.blake@arm.com * Determine the tick when a cycle begins, by default the current 1448733Sgeoffrey.blake@arm.com * one, but the argument also enables the caller to determine a 1458733Sgeoffrey.blake@arm.com * future cycle. 1468733Sgeoffrey.blake@arm.com * 1478809Sgblack@eecs.umich.edu * @param cycles The number of cycles into the future 1488852Sandreas.hansson@arm.com * 1492690Sktlim@umich.edu * @return The tick when the clock edge occurs 1508733Sgeoffrey.blake@arm.com */ 15111877Sbrandon.potter@amd.com inline Tick clockEdge(Cycles cycles = Cycles(0)) const 15211877Sbrandon.potter@amd.com { 1532315SN/A // align tick to the next clock edge 1542680SN/A update(); 1552315SN/A 1562315SN/A // figure out when this future cycle is 1572330SN/A return tick + clock * cycles; 1582680SN/A } 1592680SN/A 1602330SN/A /** 1612315SN/A * Determine the current cycle, corresponding to a tick aligned to 16210407Smitch.hayenga@arm.com * a clock edge. 16310407Smitch.hayenga@arm.com * 1642315SN/A * @return The current cycle count 1652315SN/A */ 16610407Smitch.hayenga@arm.com inline Cycles curCycle() const 1672315SN/A { 1682315SN/A // align cycle to the next clock edge. 16910407Smitch.hayenga@arm.com update(); 1702315SN/A 1712680SN/A return cycle; 1722315SN/A } 1732680SN/A 1742315SN/A /** 1752680SN/A * Based on the clock of the object, determine the tick when the 1763225Sktlim@umich.edu * next cycle begins, in other words, return the next clock edge. 1772315SN/A * 1782315SN/A * @return The tick when the next cycle starts 1798733Sgeoffrey.blake@arm.com */ 1808733Sgeoffrey.blake@arm.com Tick nextCycle() const 1818733Sgeoffrey.blake@arm.com { return clockEdge(); } 1828733Sgeoffrey.blake@arm.com 1838733Sgeoffrey.blake@arm.com inline uint64_t frequency() const { return SimClock::Frequency / clock; } 1842315SN/A 1852680SN/A inline Tick clockPeriod() const { return clock; } 1862315SN/A 1872680SN/A inline Cycles ticksToCycles(Tick tick) const 1882680SN/A { return Cycles(tick / clock); } 1892315SN/A 1902680SN/A}; 1912680SN/A 1922315SN/A#endif //__SIM_CLOCKED_OBJECT_HH__ 1932315SN/A