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Diffstat (limited to 'src/sim/clock_domain.cc')
-rw-r--r-- | src/sim/clock_domain.cc | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/src/sim/clock_domain.cc b/src/sim/clock_domain.cc new file mode 100644 index 000000000..262ae904c --- /dev/null +++ b/src/sim/clock_domain.cc @@ -0,0 +1,118 @@ +/* + * Copyright (c) 2013 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Vasileios Spiliopoulos + * Akash Bagdia + * Andreas Hansson + */ + +#include "debug/ClockDomain.hh" +#include "params/ClockDomain.hh" +#include "params/DerivedClockDomain.hh" +#include "params/SrcClockDomain.hh" +#include "sim/clock_domain.hh" + +SrcClockDomain::SrcClockDomain(const Params *p) : ClockDomain(p) +{ + clockPeriod(p->clock); +} + +void +SrcClockDomain::clockPeriod(Tick clock_period) +{ + if (clock_period == 0) { + fatal("%s has a clock period of zero\n", name()); + } + + _clockPeriod = clock_period; + + DPRINTF(ClockDomain, + "Setting clock period to %d ticks for source clock %s\n", + _clockPeriod, name()); + + // inform any derived clocks they need to updated their period + for (auto c = children.begin(); c != children.end(); ++c) { + (*c)->updateClockPeriod(); + } +} + +SrcClockDomain * +SrcClockDomainParams::create() +{ + return new SrcClockDomain(this); +} + +DerivedClockDomain::DerivedClockDomain(const Params *p) : + ClockDomain(p), + parent(*p->clk_domain), + clockDivider(p->clk_divider) +{ + // Ensure that clock divider setting works as frequency divider and never + // work as frequency multiplier + if (clockDivider < 1) { + fatal("Clock divider param cannot be less than 1"); + } + + // let the parent keep track of this derived domain so that it can + // propagate changes + parent.addDerivedDomain(this); + + // update our clock period based on the parents clock + updateClockPeriod(); +} + +void +DerivedClockDomain::updateClockPeriod() +{ + // recalculate the clock period, relying on the fact that changes + // propagate downwards in the tree + _clockPeriod = parent.clockPeriod() * clockDivider; + + DPRINTF(ClockDomain, + "Setting clock period to %d ticks for derived clock %s\n", + _clockPeriod, name()); + + // inform any derived clocks + for (auto c = children.begin(); c != children.end(); ++c) { + (*c)->updateClockPeriod(); + } +} + +DerivedClockDomain * +DerivedClockDomainParams::create() +{ + return new DerivedClockDomain(this); +} |