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 "tuning.hpp"
21 #include "util.hpp"
22 #include "zone.hpp"
23 
24 #include <algorithm>
25 #include <cmath>
26 #include <iostream>
27 
28 namespace pid_control
29 {
30 
31 ThermalType getThermalType(const std::string& typeString)
32 {
33     /* Currently it only supports the two types. */
34     return (typeString == "temp") ? ThermalType::absolute : ThermalType::margin;
35 }
36 
37 bool isThermalType(const std::string& typeString)
38 {
39     static const std::vector<std::string> thermalTypes = {"temp", "margin"};
40     return std::count(thermalTypes.begin(), thermalTypes.end(), typeString);
41 }
42 
43 std::unique_ptr<PIDController> ThermalController::createThermalPid(
44     ZoneInterface* owner, const std::string& id,
45     const std::vector<std::string>& inputs, double setpoint,
46     const ec::pidinfo& initial, const ThermalType& type)
47 {
48     // ThermalController requires at least 1 input
49     if (inputs.empty())
50     {
51         throw ControllerBuildException("Thermal controller missing inputs");
52         return nullptr;
53     }
54 
55     auto thermal = std::make_unique<ThermalController>(id, inputs, type, owner);
56 
57     ec::pid_info_t* info = thermal->getPIDInfo();
58     thermal->setSetpoint(setpoint);
59 
60     initializePIDStruct(info, initial);
61 
62     return thermal;
63 }
64 
65 // bmc_host_sensor_value_double
66 double ThermalController::inputProc(void)
67 {
68     double value;
69     const double& (*compare)(const double&, const double&);
70     if (type == ThermalType::margin)
71     {
72         value = std::numeric_limits<double>::max();
73         compare = std::min<double>;
74     }
75     else
76     {
77         value = std::numeric_limits<double>::lowest();
78         compare = std::max<double>;
79     }
80 
81     bool acceptable = false;
82     for (const auto& in : _inputs)
83     {
84         double cachedValue = _owner->getCachedValue(in);
85 
86         // Less than 0 is perfectly OK for temperature, but must not be NAN
87         if (!(std::isfinite(cachedValue)))
88         {
89             continue;
90         }
91 
92         value = compare(value, cachedValue);
93         acceptable = true;
94     }
95 
96     if (!acceptable)
97     {
98         // While not optimal, zero is better than garbage
99         value = 0;
100     }
101 
102     if (debugEnabled)
103     {
104         std::cerr << getID() << " choose the temperature value: " << value
105                   << "\n";
106     }
107 
108     return value;
109 }
110 
111 // bmc_get_setpt
112 double ThermalController::setptProc(void)
113 {
114     double setpoint = getSetpoint();
115 
116     /* TODO(venture): Thermal setpoint invalid? */
117 #if 0
118     if (-1 == setpoint)
119     {
120         return 0.0f;
121     }
122     else
123     {
124         return setpoint;
125     }
126 #endif
127     return setpoint;
128 }
129 
130 // bmc_set_pid_output
131 void ThermalController::outputProc(double value)
132 {
133     _owner->addSetPoint(value, _id);
134 
135     if (debugEnabled)
136     {
137         std::cerr << getID() << " pid output pwm: " << value << "\n";
138     }
139 
140     return;
141 }
142 
143 } // namespace pid_control
144