1 /**
2  * Copyright 2017 Google Inc.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "thermalcontroller.hpp"
18 
19 #include "errors/exception.hpp"
20 #include "util.hpp"
21 #include "zone.hpp"
22 
23 #include <algorithm>
24 #include <cmath>
25 #include <iostream>
26 
27 namespace pid_control
28 {
29 
30 ThermalType getThermalType(const std::string& typeString)
31 {
32     /* Currently it only supports the two types. */
33     return (typeString == "temp") ? ThermalType::absolute : ThermalType::margin;
34 }
35 
36 bool isThermalType(const std::string& typeString)
37 {
38     static const std::vector<std::string> thermalTypes = {"temp", "margin"};
39     return std::count(thermalTypes.begin(), thermalTypes.end(), typeString);
40 }
41 
42 std::unique_ptr<PIDController> ThermalController::createThermalPid(
43     ZoneInterface* owner, const std::string& id,
44     const std::vector<std::string>& inputs, double setpoint,
45     const ec::pidinfo& initial, const ThermalType& type)
46 {
47     // ThermalController requires at least 1 input
48     if (inputs.empty())
49     {
50         throw ControllerBuildException("Thermal controller missing inputs");
51         return nullptr;
52     }
53 
54     auto thermal = std::make_unique<ThermalController>(id, inputs, type, owner);
55 
56     ec::pid_info_t* info = thermal->getPIDInfo();
57     thermal->setSetpoint(setpoint);
58 
59     initializePIDStruct(info, initial);
60 
61     return thermal;
62 }
63 
64 // bmc_host_sensor_value_double
65 double ThermalController::inputProc(void)
66 {
67     double value;
68     const double& (*compare)(const double&, const double&);
69     if (type == ThermalType::margin)
70     {
71         value = std::numeric_limits<double>::max();
72         compare = std::min<double>;
73     }
74     else
75     {
76         value = std::numeric_limits<double>::lowest();
77         compare = std::max<double>;
78     }
79 
80     bool acceptable = false;
81     for (const auto& in : _inputs)
82     {
83         double cachedValue = _owner->getCachedValue(in);
84 
85         // Less than 0 is perfectly OK for temperature, but must not be NAN
86         if (!(std::isfinite(cachedValue)))
87         {
88             continue;
89         }
90 
91         value = compare(value, cachedValue);
92         acceptable = true;
93     }
94 
95     if (!acceptable)
96     {
97         // While not optimal, zero is better than garbage
98         value = 0;
99     }
100 
101     return value;
102 }
103 
104 // bmc_get_setpt
105 double ThermalController::setptProc(void)
106 {
107     double setpoint = getSetpoint();
108 
109     /* TODO(venture): Thermal setpoint invalid? */
110 #if 0
111     if (-1 == setpoint)
112     {
113         return 0.0f;
114     }
115     else
116     {
117         return setpoint;
118     }
119 #endif
120     return setpoint;
121 }
122 
123 // bmc_set_pid_output
124 void ThermalController::outputProc(double value)
125 {
126     _owner->addSetPoint(value);
127 
128     return;
129 }
130 
131 } // namespace pid_control
132