voltage_domain.cc revision 10395
1/* 2 * Copyright (c) 2012-2014 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 7 * property including but not limited to intellectual property relating 8 * to a hardware implementation of the functionality of the software 9 * licensed hereunder. You may use the software subject to the license 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 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions are 16 * met: redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer; 18 * redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution; 21 * neither the name of the copyright holders nor the names of its 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 28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 * 37 * Authors: Vasileios Spiliopoulos 38 * Akash Bagdia 39 */ 40 41#include <algorithm> 42 43#include "base/statistics.hh" 44#include "debug/VoltageDomain.hh" 45#include "params/VoltageDomain.hh" 46#include "sim/sim_object.hh" 47#include "sim/voltage_domain.hh" 48 49VoltageDomain::VoltageDomain(const Params *p) 50 : SimObject(p), voltageOpPoints(p->voltage), _perfLevel(0) 51{ 52 fatal_if(voltageOpPoints.empty(), "DVFS: Empty set of voltages for "\ 53 "voltage domain %s\n", name()); 54 55 // Voltages must be sorted in descending order. 56 fatal_if(!std::is_sorted(voltageOpPoints.begin(), voltageOpPoints.end(), 57 std::greater<Voltages::value_type>()), "DVFS: Voltage operation "\ 58 "points not in descending order for voltage domain %s\n", 59 name()); 60} 61 62void 63VoltageDomain::perfLevel(PerfLevel perf_level) 64{ 65 chatty_assert(perf_level < voltageOpPoints.size(), 66 "DVFS: Requested voltage ID %d is outside the known "\ 67 "range for domain %s.\n", perf_level, name()); 68 69 if (perf_level == _perfLevel) { 70 // Silently ignore identical overwrites 71 return; 72 } 73 74 _perfLevel = perf_level; 75 76 DPRINTF(VoltageDomain, "Setting voltage to %.3fV idx: %d for domain %s\n", 77 voltage(), perf_level, name()); 78} 79 80bool 81VoltageDomain::sanitiseVoltages() 82{ 83 if (numVoltages() == 1) 84 return false; 85 86 // Find the highest requested performance level and update the voltage 87 // domain with it 88 PerfLevel perf_max = (PerfLevel)-1; 89 for (auto dit = srcClockChildren.begin(); dit != srcClockChildren.end(); ++dit) { 90 SrcClockDomain* d = *dit; 91 chatty_assert(d->voltageDomain() == this, "DVFS: Clock domain %s "\ 92 "(id: %d) should not be registered with voltage domain "\ 93 "%s\n", d->name(), d->domainID(), name()); 94 95 PerfLevel perf = d->perfLevel(); 96 97 DPRINTF(VoltageDomain, "DVFS: Clock domain %s (id: %d) requests perf "\ 98 "level %d\n", d->name(), d->domainID(), perf); 99 100 // NOTE: Descending sort of performance levels: 0 - fast, 5 - slow 101 if (perf < perf_max) { 102 DPRINTF(VoltageDomain, "DVFS: Updating max perf level %d -> %d\n", 103 perf_max, perf); 104 perf_max = perf; 105 } 106 } 107 DPRINTF(VoltageDomain, "DVFS: Setting perf level of voltage domain %s "\ 108 "from %d to %d.\n", name(), perfLevel(), perf_max); 109 110 // Set the performance level 111 if (perf_max != perfLevel()) { 112 perfLevel(perf_max); 113 return true; 114 } else { 115 return false; 116 } 117} 118 119void 120VoltageDomain::startup() { 121 bool changed = sanitiseVoltages(); 122 if (changed) { 123 warn("DVFS: Perf level for voltage domain %s adapted to "\ 124 "requested perf levels from source clock domains.\n", name()); 125 } 126} 127 128void 129VoltageDomain::regStats() 130{ 131 currentVoltage 132 .method(this, &VoltageDomain::voltage) 133 .name(params()->name + ".voltage") 134 .desc("Voltage in Volts") 135 ; 136} 137 138VoltageDomain * 139VoltageDomainParams::create() 140{ 141 return new VoltageDomain(this); 142} 143 144void 145VoltageDomain::serialize(std::ostream &os) { 146 SERIALIZE_SCALAR(_perfLevel); 147} 148 149void 150VoltageDomain::unserialize(Checkpoint *cp, const std::string §ion) { 151 UNSERIALIZE_SCALAR(_perfLevel); 152 perfLevel(_perfLevel); 153} 154