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Diffstat (limited to 'src/sim/clock_domain.hh')
-rw-r--r-- | src/sim/clock_domain.hh | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/src/sim/clock_domain.hh b/src/sim/clock_domain.hh new file mode 100644 index 000000000..c3f53e675 --- /dev/null +++ b/src/sim/clock_domain.hh @@ -0,0 +1,160 @@ +/* + * 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 + */ + +/** + * @file + * ClockDomain declarations. + */ + +#ifndef __SIM_CLOCK_DOMAIN_HH__ +#define __SIM_CLOCK_DOMAIN_HH__ + +#include "base/statistics.hh" +#include "params/ClockDomain.hh" +#include "params/DerivedClockDomain.hh" +#include "params/SrcClockDomain.hh" +#include "sim/sim_object.hh" + +/** + * Forward declaration + */ +class DerivedClockDomain; + +/** + * The ClockDomain provides clock to group of clocked objects bundled + * under the same clock domain. The clock domains provide support for + * a hierarchial structure with source and derived domains. + */ +class ClockDomain : public SimObject +{ + + protected: + + /** + * Pre-computed clock period in ticks. This is populated by the + * inheriting classes based on how their period is determined. + */ + Tick _clockPeriod; + + /** + * Pointers to potential derived clock domains so we can propagate + * changes. + */ + std::vector<DerivedClockDomain*> children; + + public: + + typedef ClockDomainParams Params; + ClockDomain(const Params *p) : SimObject(p), _clockPeriod(0) {} + + /** + * Get the clock period. + * + * @return Clock period in ticks + */ + inline Tick clockPeriod() const { return _clockPeriod; } + + /** + * Add a derived domain. + * + * @param Derived domain to add as a child + */ + void addDerivedDomain(DerivedClockDomain *clock_domain) + { children.push_back(clock_domain); } + +}; + +/** + * The source clock domains provides the notion of a clock domain that is + * connected to a tunable clock source. It maintains the clock period and + * provides methods for setting/getting the clock. + */ +class SrcClockDomain : public ClockDomain +{ + + public: + + typedef SrcClockDomainParams Params; + SrcClockDomain(const Params *p); + + /** + * Set new clock value + * @param clock The new clock period in ticks + */ + void clockPeriod(Tick clock_period); + +}; + +/** + * The derived clock domains provides the notion of a clock domain + * that is connected to a parent clock domain that can either be a + * source clock domain or a derived clock domain. It maintains the + * clock divider and provides methods for getting the clock. + */ +class DerivedClockDomain: public ClockDomain +{ + + public: + + typedef DerivedClockDomainParams Params; + DerivedClockDomain(const Params *p); + + /** + * Called by the parent clock domain to propagate changes. This + * also involves propagating the change further to any children of + * the derived domain itself. + */ + void updateClockPeriod(); + + private: + + /** + * Reference to the parent clock domain this clock domain derives + * its clock period from + */ + ClockDomain &parent; + + /** + * Local clock divider of the domain + */ + const uint64_t clockDivider; +}; + +#endif |