2 * Copyright (c) 2013 ARM Limited
3 * Copyright (c) 2013 Cornell University
6 * The license below extends only to copyright in the software and shall
7 * not be construed as granting a license to any other intellectual
8 * property including but not limited to intellectual property relating
9 * to a hardware implementation of the functionality of the software
10 * licensed hereunder. You may use the software subject to the license
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12 * unmodified and in its entirety in all distributions of the software,
13 * modified or unmodified, in source code or in binary form.
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18 * notice, this list of conditions and the following disclaimer;
19 * redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution;
22 * neither the name of the copyright holders nor the names of its
23 * contributors may be used to endorse or promote products derived from
24 * this software without specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
27 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
28 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
29 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
30 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
31 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
32 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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36 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 * Authors: Vasileios Spiliopoulos
44 #include "debug/ClockDomain.hh"
45 #include "params/ClockDomain.hh"
46 #include "params/DerivedClockDomain.hh"
47 #include "params/SrcClockDomain.hh"
48 #include "sim/clock_domain.hh"
49 #include "sim/voltage_domain.hh"
50 #include "sim/clocked_object.hh"
53 ClockDomain::regStats()
55 using namespace Stats
;
57 // Expose the current clock period as a stat for observability in
61 .name(params()->name
+ ".clock")
62 .desc("Clock period in ticks")
67 ClockDomain::voltage() const
69 return _voltageDomain
->voltage();
72 SrcClockDomain::SrcClockDomain(const Params
*p
) :
73 ClockDomain(p
, p
->voltage_domain
)
75 clockPeriod(p
->clock
);
79 SrcClockDomain::clockPeriod(Tick clock_period
)
81 if (clock_period
== 0) {
82 fatal("%s has a clock period of zero\n", name());
85 // Align all members to the current tick
86 for (auto m
= members
.begin(); m
!= members
.end(); ++m
) {
87 (*m
)->updateClockPeriod();
90 _clockPeriod
= clock_period
;
93 "Setting clock period to %d ticks for source clock %s\n",
94 _clockPeriod
, name());
96 // inform any derived clocks they need to updated their period
97 for (auto c
= children
.begin(); c
!= children
.end(); ++c
) {
98 (*c
)->updateClockPeriod();
103 SrcClockDomainParams::create()
105 return new SrcClockDomain(this);
108 DerivedClockDomain::DerivedClockDomain(const Params
*p
) :
109 ClockDomain(p
, p
->clk_domain
->voltageDomain()),
110 parent(*p
->clk_domain
),
111 clockDivider(p
->clk_divider
)
113 // Ensure that clock divider setting works as frequency divider and never
114 // work as frequency multiplier
115 if (clockDivider
< 1) {
116 fatal("Clock divider param cannot be less than 1");
119 // let the parent keep track of this derived domain so that it can
121 parent
.addDerivedDomain(this);
123 // update our clock period based on the parents clock
128 DerivedClockDomain::updateClockPeriod()
130 // Align all members to the current tick
131 for (auto m
= members
.begin(); m
!= members
.end(); ++m
) {
132 (*m
)->updateClockPeriod();
135 // recalculate the clock period, relying on the fact that changes
136 // propagate downwards in the tree
137 _clockPeriod
= parent
.clockPeriod() * clockDivider
;
140 "Setting clock period to %d ticks for derived clock %s\n",
141 _clockPeriod
, name());
143 // inform any derived clocks
144 for (auto c
= children
.begin(); c
!= children
.end(); ++c
) {
145 (*c
)->updateClockPeriod();
150 DerivedClockDomainParams::create()
152 return new DerivedClockDomain(this);