clocked_object.hh revision 11532
12SN/A/* 210349Sandreas.hansson@arm.com * Copyright (c) 2012-2013, 2015-2016 ARM Limited 310349Sandreas.hansson@arm.com * Copyright (c) 2013 Cornell University 410349Sandreas.hansson@arm.com * All rights reserved 510349Sandreas.hansson@arm.com * 610349Sandreas.hansson@arm.com * The license below extends only to copyright in the software and shall 710349Sandreas.hansson@arm.com * not be construed as granting a license to any other intellectual 810349Sandreas.hansson@arm.com * property including but not limited to intellectual property relating 910349Sandreas.hansson@arm.com * to a hardware implementation of the functionality of the software 1010349Sandreas.hansson@arm.com * licensed hereunder. You may use the software subject to the license 1110349Sandreas.hansson@arm.com * terms below provided that you ensure that this notice is replicated 1210349Sandreas.hansson@arm.com * unmodified and in its entirety in all distributions of the software, 1310349Sandreas.hansson@arm.com * modified or unmodified, in source code or in binary form. 141762SN/A * 152SN/A * Redistribution and use in source and binary forms, with or without 162SN/A * modification, are permitted provided that the following conditions are 172SN/A * met: redistributions of source code must retain the above copyright 182SN/A * notice, this list of conditions and the following disclaimer; 192SN/A * redistributions in binary form must reproduce the above copyright 202SN/A * notice, this list of conditions and the following disclaimer in the 212SN/A * documentation and/or other materials provided with the distribution; 222SN/A * neither the name of the copyright holders nor the names of its 232SN/A * contributors may be used to endorse or promote products derived from 242SN/A * this software without specific prior written permission. 252SN/A * 262SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 272SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 282SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 292SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 302SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 312SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 322SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 332SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 342SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 352SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 362SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 372SN/A * 382SN/A * Authors: Andreas Hansson 392665Ssaidi@eecs.umich.edu * Christopher Torng 402665Ssaidi@eecs.umich.edu * Akash Bagdia 412665Ssaidi@eecs.umich.edu * David Guillen Fandos 4210349Sandreas.hansson@arm.com */ 432SN/A 442SN/A/** 4511793Sbrandon.potter@amd.com * @file 4611793Sbrandon.potter@amd.com * ClockedObject declaration and implementation. 4710349Sandreas.hansson@arm.com */ 4810349Sandreas.hansson@arm.com 495190Ssaidi@eecs.umich.edu#ifndef __SIM_CLOCKED_OBJECT_HH__ 505190Ssaidi@eecs.umich.edu#define __SIM_CLOCKED_OBJECT_HH__ 512SN/A 525190Ssaidi@eecs.umich.edu#include "base/callback.hh" 532SN/A#include "base/intmath.hh" 5410349Sandreas.hansson@arm.com#include "base/misc.hh" 555190Ssaidi@eecs.umich.edu#include "enums/PwrState.hh" 562SN/A#include "params/ClockedObject.hh" 572SN/A#include "sim/core.hh" 585190Ssaidi@eecs.umich.edu#include "sim/clock_domain.hh" 592SN/A#include "sim/sim_object.hh" 605190Ssaidi@eecs.umich.edu 612SN/A/** 622SN/A * Helper class for objects that need to be clocked. Clocked objects 635190Ssaidi@eecs.umich.edu * typically inherit from this class. Objects that need SimObject 641954SN/A * functionality as well should inherit from ClockedObject. 655190Ssaidi@eecs.umich.edu */ 663483Ssaidi@eecs.umich.educlass Clocked 6710349Sandreas.hansson@arm.com{ 6810349Sandreas.hansson@arm.com 695190Ssaidi@eecs.umich.edu private: 7010349Sandreas.hansson@arm.com // the tick value of the next clock edge (>= curTick()) at the 711954SN/A // time of the last call to update() 725190Ssaidi@eecs.umich.edu mutable Tick tick; 735190Ssaidi@eecs.umich.edu 7410905Sandreas.sandberg@arm.com // The cycle counter value corresponding to the current value of 755190Ssaidi@eecs.umich.edu // 'tick' 7610349Sandreas.hansson@arm.com mutable Cycles cycle; 7710349Sandreas.hansson@arm.com 7810349Sandreas.hansson@arm.com /** 7910349Sandreas.hansson@arm.com * Align cycle and tick to the next clock edge if not already done. When 8010349Sandreas.hansson@arm.com * complete, tick must be at least curTick(). 8110349Sandreas.hansson@arm.com */ 8210905Sandreas.sandberg@arm.com void update() const 835190Ssaidi@eecs.umich.edu { 845190Ssaidi@eecs.umich.edu // both tick and cycle are up-to-date and we are done, note 855190Ssaidi@eecs.umich.edu // that the >= is important as it captures cases where tick 8610905Sandreas.sandberg@arm.com // has already passed curTick() 875190Ssaidi@eecs.umich.edu if (tick >= curTick()) 8810349Sandreas.hansson@arm.com return; 895190Ssaidi@eecs.umich.edu 9010349Sandreas.hansson@arm.com // optimise for the common case and see if the tick should be 9110349Sandreas.hansson@arm.com // advanced by a single clock period 9210349Sandreas.hansson@arm.com tick += clockPeriod(); 9310349Sandreas.hansson@arm.com ++cycle; 9410905Sandreas.sandberg@arm.com 9510349Sandreas.hansson@arm.com // see if we are done at this point 9610349Sandreas.hansson@arm.com if (tick >= curTick()) 9710349Sandreas.hansson@arm.com return; 985190Ssaidi@eecs.umich.edu 995190Ssaidi@eecs.umich.edu // if not, we have to recalculate the cycle and tick, we 1005190Ssaidi@eecs.umich.edu // perform the calculations in terms of relative cycles to 101 // allow changes to the clock period in the future 102 Cycles elapsedCycles(divCeil(curTick() - tick, clockPeriod())); 103 cycle += elapsedCycles; 104 tick += elapsedCycles * clockPeriod(); 105 } 106 107 /** 108 * The clock domain this clocked object belongs to 109 */ 110 ClockDomain &clockDomain; 111 112 protected: 113 114 /** 115 * Create a clocked object and set the clock domain based on the 116 * parameters. 117 */ 118 Clocked(ClockDomain &clk_domain) 119 : tick(0), cycle(0), clockDomain(clk_domain) 120 { 121 // Register with the clock domain, so that if the clock domain 122 // frequency changes, we can update this object's tick. 123 clockDomain.registerWithClockDomain(this); 124 } 125 126 Clocked(Clocked &) = delete; 127 Clocked &operator=(Clocked &) = delete; 128 129 /** 130 * Virtual destructor due to inheritance. 131 */ 132 virtual ~Clocked() { } 133 134 /** 135 * Reset the object's clock using the current global tick value. Likely 136 * to be used only when the global clock is reset. Currently, this done 137 * only when Ruby is done warming up the memory system. 138 */ 139 void resetClock() const 140 { 141 Cycles elapsedCycles(divCeil(curTick(), clockPeriod())); 142 cycle = elapsedCycles; 143 tick = elapsedCycles * clockPeriod(); 144 } 145 146 public: 147 148 /** 149 * Update the tick to the current tick. 150 * 151 */ 152 inline void updateClockPeriod() const 153 { 154 update(); 155 } 156 157 /** 158 * Determine the tick when a cycle begins, by default the current one, but 159 * the argument also enables the caller to determine a future cycle. When 160 * curTick() is on a clock edge, the number of cycles in the parameter is 161 * added to curTick() to be returned. When curTick() is not aligned to a 162 * clock edge, the number of cycles in the parameter is added to the next 163 * clock edge. 164 * 165 * @param cycles The number of cycles into the future 166 * 167 * @return The start tick when the requested clock edge occurs. Precisely, 168 * this tick can be 169 * curTick() + [0, clockPeriod()) + clockPeriod() * cycles 170 */ 171 inline Tick clockEdge(Cycles cycles = Cycles(0)) const 172 { 173 // align tick to the next clock edge 174 update(); 175 176 // figure out when this future cycle is 177 return tick + clockPeriod() * cycles; 178 } 179 180 /** 181 * Determine the current cycle, corresponding to a tick aligned to 182 * a clock edge. 183 * 184 * @return When curTick() is on a clock edge, return the Cycle corresponding 185 * to that clock edge. When curTick() is not on a clock edge, return the 186 * Cycle corresponding to the next clock edge. 187 */ 188 inline Cycles curCycle() const 189 { 190 // align cycle to the next clock edge. 191 update(); 192 193 return cycle; 194 } 195 196 /** 197 * Based on the clock of the object, determine the start tick of the first 198 * cycle that is at least one cycle in the future. When curTick() is at the 199 * current cycle edge, this returns the next clock edge. When calling this 200 * during the middle of a cycle, this returns 2 clock edges in the future. 201 * 202 * @return The start tick of the first cycle that is at least one cycle in 203 * the future. Precisely, the returned tick can be in the range 204 * curTick() + [clockPeriod(), 2 * clockPeriod()) 205 */ 206 Tick nextCycle() const 207 { return clockEdge(Cycles(1)); } 208 209 inline uint64_t frequency() const 210 { 211 return SimClock::Frequency / clockPeriod(); 212 } 213 214 inline Tick clockPeriod() const 215 { 216 return clockDomain.clockPeriod(); 217 } 218 219 inline double voltage() const 220 { 221 return clockDomain.voltage(); 222 } 223 224 inline Cycles ticksToCycles(Tick t) const 225 { return Cycles(divCeil(t, clockPeriod())); } 226 227 inline Tick cyclesToTicks(Cycles c) const 228 { return clockPeriod() * c; } 229}; 230 231/** 232 * The ClockedObject class extends the SimObject with a clock and 233 * accessor functions to relate ticks to the cycles of the object. 234 */ 235class ClockedObject 236 : public SimObject, public Clocked 237{ 238 public: 239 ClockedObject(const ClockedObjectParams *p); 240 241 /** Parameters of ClockedObject */ 242 typedef ClockedObjectParams Params; 243 const Params* params() const 244 { return reinterpret_cast<const Params*>(_params); } 245 246 void serialize(CheckpointOut &cp) const override; 247 void unserialize(CheckpointIn &cp) override; 248 249 inline Enums::PwrState pwrState() const 250 { return _currPwrState; } 251 252 inline std::string pwrStateName() const 253 { return Enums::PwrStateStrings[_currPwrState]; } 254 255 /** Returns the percentage residency for each power state */ 256 std::vector<double> pwrStateWeights() const; 257 258 /** 259 * Record stats values like state residency by computing the time 260 * difference from previous update. Also, updates the previous evaluation 261 * tick once all stats are recorded. 262 * Usually called on power state change and stats dump callback. 263 */ 264 void computeStats(); 265 266 void pwrState(Enums::PwrState); 267 void regStats() override; 268 269 protected: 270 271 /** To keep track of the current power state */ 272 Enums::PwrState _currPwrState; 273 274 Tick prvEvalTick; 275 276 Stats::Scalar numPwrStateTransitions; 277 Stats::Distribution pwrStateClkGateDist; 278 Stats::Vector pwrStateResidencyTicks; 279 280}; 281 282class ClockedObjectDumpCallback : public Callback 283{ 284 ClockedObject *co; 285 public: 286 ClockedObjectDumpCallback(ClockedObject *co_t) : co(co_t) {} 287 virtual void process() { co->computeStats(); }; 288}; 289 290#endif //__SIM_CLOCKED_OBJECT_HH__ 291