1 /*
2 // Copyright (c) 2018 Intel Corporation
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 #include "dbusconfiguration.hpp"
17 
18 #include "conf.hpp"
19 #include "dbushelper.hpp"
20 #include "dbusutil.hpp"
21 #include "util.hpp"
22 
23 #include <boost/asio/steady_timer.hpp>
24 #include <sdbusplus/bus.hpp>
25 #include <sdbusplus/bus/match.hpp>
26 #include <sdbusplus/exception.hpp>
27 
28 #include <algorithm>
29 #include <chrono>
30 #include <functional>
31 #include <iostream>
32 #include <list>
33 #include <set>
34 #include <unordered_map>
35 #include <variant>
36 
37 namespace pid_control
38 {
39 
40 constexpr const char* pidConfigurationInterface =
41     "xyz.openbmc_project.Configuration.Pid";
42 constexpr const char* objectManagerInterface =
43     "org.freedesktop.DBus.ObjectManager";
44 constexpr const char* pidZoneConfigurationInterface =
45     "xyz.openbmc_project.Configuration.Pid.Zone";
46 constexpr const char* stepwiseConfigurationInterface =
47     "xyz.openbmc_project.Configuration.Stepwise";
48 constexpr const char* thermalControlIface =
49     "xyz.openbmc_project.Control.ThermalMode";
50 constexpr const char* sensorInterface = "xyz.openbmc_project.Sensor.Value";
51 constexpr const char* defaultPwmInterface =
52     "xyz.openbmc_project.Control.FanPwm";
53 
54 using Association = std::tuple<std::string, std::string, std::string>;
55 using Associations = std::vector<Association>;
56 
57 namespace thresholds
58 {
59 constexpr const char* warningInterface =
60     "xyz.openbmc_project.Sensor.Threshold.Warning";
61 constexpr const char* criticalInterface =
62     "xyz.openbmc_project.Sensor.Threshold.Critical";
63 const std::array<const char*, 4> types = {"CriticalLow", "CriticalHigh",
64                                           "WarningLow", "WarningHigh"};
65 
66 } // namespace thresholds
67 
68 namespace dbus_configuration
69 {
70 using SensorInterfaceType = std::pair<std::string, std::string>;
71 
72 inline std::string getSensorNameFromPath(const std::string& dbusPath)
73 {
74     return dbusPath.substr(dbusPath.find_last_of("/") + 1);
75 }
76 
77 inline std::string sensorNameToDbusName(const std::string& sensorName)
78 {
79     std::string retString = sensorName;
80     std::replace(retString.begin(), retString.end(), ' ', '_');
81     return retString;
82 }
83 
84 std::vector<std::string> getSelectedProfiles(sdbusplus::bus_t& bus)
85 {
86     std::vector<std::string> ret;
87     auto mapper = bus.new_method_call("xyz.openbmc_project.ObjectMapper",
88                                       "/xyz/openbmc_project/object_mapper",
89                                       "xyz.openbmc_project.ObjectMapper",
90                                       "GetSubTree");
91     mapper.append("/", 0, std::array<const char*, 1>{thermalControlIface});
92     std::unordered_map<
93         std::string, std::unordered_map<std::string, std::vector<std::string>>>
94         respData;
95 
96     try
97     {
98         auto resp = bus.call(mapper);
99         resp.read(respData);
100     }
101     catch (const sdbusplus::exception_t&)
102     {
103         // can't do anything without mapper call data
104         throw std::runtime_error("ObjectMapper Call Failure");
105     }
106     if (respData.empty())
107     {
108         // if the user has profiles but doesn't expose the interface to select
109         // one, just go ahead without using profiles
110         return ret;
111     }
112 
113     // assumption is that we should only have a small handful of selected
114     // profiles at a time (probably only 1), so calling each individually should
115     // not incur a large cost
116     for (const auto& objectPair : respData)
117     {
118         const std::string& path = objectPair.first;
119         for (const auto& ownerPair : objectPair.second)
120         {
121             const std::string& busName = ownerPair.first;
122             auto getProfile =
123                 bus.new_method_call(busName.c_str(), path.c_str(),
124                                     "org.freedesktop.DBus.Properties", "Get");
125             getProfile.append(thermalControlIface, "Current");
126             std::variant<std::string> variantResp;
127             try
128             {
129                 auto resp = bus.call(getProfile);
130                 resp.read(variantResp);
131             }
132             catch (const sdbusplus::exception_t&)
133             {
134                 throw std::runtime_error("Failure getting profile");
135             }
136             std::string mode = std::get<std::string>(variantResp);
137             ret.emplace_back(std::move(mode));
138         }
139     }
140     if constexpr (pid_control::conf::DEBUG)
141     {
142         std::cout << "Profiles selected: ";
143         for (const auto& profile : ret)
144         {
145             std::cout << profile << " ";
146         }
147         std::cout << "\n";
148     }
149     return ret;
150 }
151 
152 int eventHandler(sd_bus_message* m, void* context, sd_bus_error*)
153 {
154     if (context == nullptr || m == nullptr)
155     {
156         throw std::runtime_error("Invalid match");
157     }
158 
159     // we skip associations because the mapper populates these, not the sensors
160     const std::array<const char*, 2> skipList = {
161         "xyz.openbmc_project.Association",
162         "xyz.openbmc_project.Association.Definitions"};
163 
164     sdbusplus::message_t message(m);
165     if (std::string(message.get_member()) == "InterfacesAdded")
166     {
167         sdbusplus::message::object_path path;
168         std::unordered_map<
169             std::string,
170             std::unordered_map<std::string, std::variant<Associations, bool>>>
171             data;
172 
173         message.read(path, data);
174 
175         for (const char* skip : skipList)
176         {
177             auto find = data.find(skip);
178             if (find != data.end())
179             {
180                 data.erase(find);
181                 if (data.empty())
182                 {
183                     return 1;
184                 }
185             }
186         }
187 
188         if constexpr (pid_control::conf::DEBUG)
189         {
190             std::cout << "New config detected: " << path.str << std::endl;
191             for (auto& d : data)
192             {
193                 std::cout << "\tdata is " << d.first << std::endl;
194                 for (auto& second : d.second)
195                 {
196                     std::cout << "\t\tdata is " << second.first << std::endl;
197                 }
198             }
199         }
200     }
201 
202     boost::asio::steady_timer* timer =
203         static_cast<boost::asio::steady_timer*>(context);
204 
205     // do a brief sleep as we tend to get a bunch of these events at
206     // once
207     timer->expires_after(std::chrono::seconds(2));
208     timer->async_wait([](const boost::system::error_code ec) {
209         if (ec == boost::asio::error::operation_aborted)
210         {
211             /* another timer started*/
212             return;
213         }
214 
215         std::cout << "New configuration detected, reloading\n.";
216         tryRestartControlLoops();
217     });
218 
219     return 1;
220 }
221 
222 void createMatches(sdbusplus::bus_t& bus, boost::asio::steady_timer& timer)
223 {
224     // this is a list because the matches can't be moved
225     static std::list<sdbusplus::bus::match_t> matches;
226 
227     const std::array<std::string, 4> interfaces = {
228         thermalControlIface, pidConfigurationInterface,
229         pidZoneConfigurationInterface, stepwiseConfigurationInterface};
230 
231     // this list only needs to be created once
232     if (!matches.empty())
233     {
234         return;
235     }
236 
237     // we restart when the configuration changes or there are new sensors
238     for (const auto& interface : interfaces)
239     {
240         matches.emplace_back(
241             bus,
242             "type='signal',member='PropertiesChanged',arg0namespace='" +
243                 interface + "'",
244             eventHandler, &timer);
245     }
246     matches.emplace_back(
247         bus,
248         "type='signal',member='InterfacesAdded',arg0path='/xyz/openbmc_project/"
249         "sensors/'",
250         eventHandler, &timer);
251     matches.emplace_back(bus,
252                          "type='signal',member='InterfacesRemoved',arg0path='/"
253                          "xyz/openbmc_project/sensors/'",
254                          eventHandler, &timer);
255 }
256 
257 /**
258  * retrieve an attribute from the pid configuration map
259  * @param[in] base - the PID configuration map, keys are the attributes and
260  * value is the variant associated with that attribute.
261  * @param attributeName - the name of the attribute
262  * @return a variant holding the value associated with a key
263  * @throw runtime_error : attributeName is not in base
264  */
265 inline DbusVariantType getPIDAttribute(
266     const std::unordered_map<std::string, DbusVariantType>& base,
267     const std::string& attributeName)
268 {
269     auto search = base.find(attributeName);
270     if (search == base.end())
271     {
272         throw std::runtime_error("missing attribute " + attributeName);
273     }
274     return search->second;
275 }
276 
277 inline void getCycleTimeSetting(
278     const std::unordered_map<std::string, DbusVariantType>& zone,
279     const int zoneIndex, const std::string& attributeName, uint64_t& value)
280 {
281     auto findAttributeName = zone.find(attributeName);
282     if (findAttributeName != zone.end())
283     {
284         double tmpAttributeValue = std::visit(VariantToDoubleVisitor(),
285                                               zone.at(attributeName));
286         if (tmpAttributeValue >= 1.0)
287         {
288             value = static_cast<uint64_t>(tmpAttributeValue);
289         }
290         else
291         {
292             std::cerr << "Zone " << zoneIndex << ": " << attributeName
293                       << " is invalid. Use default " << value << " ms\n";
294         }
295     }
296     else
297     {
298         std::cerr << "Zone " << zoneIndex << ": " << attributeName
299                   << " cannot find setting. Use default " << value << " ms\n";
300     }
301 }
302 
303 void populatePidInfo(
304     [[maybe_unused]] sdbusplus::bus_t& bus,
305     const std::unordered_map<std::string, DbusVariantType>& base,
306     conf::ControllerInfo& info, const std::string* thresholdProperty,
307     const std::map<std::string, conf::SensorConfig>& sensorConfig)
308 {
309     info.type = std::get<std::string>(getPIDAttribute(base, "Class"));
310     if (info.type == "fan")
311     {
312         info.setpoint = 0;
313     }
314     else
315     {
316         info.setpoint = std::visit(VariantToDoubleVisitor(),
317                                    getPIDAttribute(base, "SetPoint"));
318     }
319 
320     int failsafepercent = 0;
321     auto findFailSafe = base.find("FailSafePercent");
322     if (findFailSafe != base.end())
323     {
324         failsafepercent = std::visit(VariantToDoubleVisitor(),
325                                      getPIDAttribute(base, "FailSafePercent"));
326     }
327     info.failSafePercent = failsafepercent;
328 
329     if (thresholdProperty != nullptr)
330     {
331         std::string interface;
332         if (*thresholdProperty == "WarningHigh" ||
333             *thresholdProperty == "WarningLow")
334         {
335             interface = thresholds::warningInterface;
336         }
337         else
338         {
339             interface = thresholds::criticalInterface;
340         }
341         const std::string& path = sensorConfig.at(info.inputs.front()).readPath;
342 
343         DbusHelper helper(sdbusplus::bus::new_system());
344         std::string service = helper.getService(interface, path);
345         double reading = 0;
346         try
347         {
348             helper.getProperty(service, path, interface, *thresholdProperty,
349                                reading);
350         }
351         catch (const sdbusplus::exception_t& ex)
352         {
353             // unsupported threshold, leaving reading at 0
354         }
355 
356         info.setpoint += reading;
357     }
358 
359     info.pidInfo.ts = 1.0; // currently unused
360     info.pidInfo.proportionalCoeff = std::visit(
361         VariantToDoubleVisitor(), getPIDAttribute(base, "PCoefficient"));
362     info.pidInfo.integralCoeff = std::visit(
363         VariantToDoubleVisitor(), getPIDAttribute(base, "ICoefficient"));
364     // DCoefficient is below, it is optional, same reason as in buildjson.cpp
365     info.pidInfo.feedFwdOffset = std::visit(
366         VariantToDoubleVisitor(), getPIDAttribute(base, "FFOffCoefficient"));
367     info.pidInfo.feedFwdGain = std::visit(
368         VariantToDoubleVisitor(), getPIDAttribute(base, "FFGainCoefficient"));
369     info.pidInfo.integralLimit.max = std::visit(
370         VariantToDoubleVisitor(), getPIDAttribute(base, "ILimitMax"));
371     info.pidInfo.integralLimit.min = std::visit(
372         VariantToDoubleVisitor(), getPIDAttribute(base, "ILimitMin"));
373     info.pidInfo.outLim.max = std::visit(VariantToDoubleVisitor(),
374                                          getPIDAttribute(base, "OutLimitMax"));
375     info.pidInfo.outLim.min = std::visit(VariantToDoubleVisitor(),
376                                          getPIDAttribute(base, "OutLimitMin"));
377     info.pidInfo.slewNeg = std::visit(VariantToDoubleVisitor(),
378                                       getPIDAttribute(base, "SlewNeg"));
379     info.pidInfo.slewPos = std::visit(VariantToDoubleVisitor(),
380                                       getPIDAttribute(base, "SlewPos"));
381 
382     double negativeHysteresis = 0;
383     double positiveHysteresis = 0;
384     double derivativeCoeff = 0;
385 
386     auto findNeg = base.find("NegativeHysteresis");
387     auto findPos = base.find("PositiveHysteresis");
388     auto findDerivative = base.find("DCoefficient");
389 
390     if (findNeg != base.end())
391     {
392         negativeHysteresis = std::visit(VariantToDoubleVisitor(),
393                                         findNeg->second);
394     }
395     if (findPos != base.end())
396     {
397         positiveHysteresis = std::visit(VariantToDoubleVisitor(),
398                                         findPos->second);
399     }
400     if (findDerivative != base.end())
401     {
402         derivativeCoeff = std::visit(VariantToDoubleVisitor(),
403                                      findDerivative->second);
404     }
405 
406     info.pidInfo.negativeHysteresis = negativeHysteresis;
407     info.pidInfo.positiveHysteresis = positiveHysteresis;
408     info.pidInfo.derivativeCoeff = derivativeCoeff;
409 }
410 
411 bool init(sdbusplus::bus_t& bus, boost::asio::steady_timer& timer,
412           std::map<std::string, conf::SensorConfig>& sensorConfig,
413           std::map<int64_t, conf::PIDConf>& zoneConfig,
414           std::map<int64_t, conf::ZoneConfig>& zoneDetailsConfig)
415 {
416     sensorConfig.clear();
417     zoneConfig.clear();
418     zoneDetailsConfig.clear();
419 
420     createMatches(bus, timer);
421 
422     auto mapper = bus.new_method_call("xyz.openbmc_project.ObjectMapper",
423                                       "/xyz/openbmc_project/object_mapper",
424                                       "xyz.openbmc_project.ObjectMapper",
425                                       "GetSubTree");
426     mapper.append("/", 0,
427                   std::array<const char*, 6>{
428                       objectManagerInterface, pidConfigurationInterface,
429                       pidZoneConfigurationInterface,
430                       stepwiseConfigurationInterface, sensorInterface,
431                       defaultPwmInterface});
432     std::unordered_map<
433         std::string, std::unordered_map<std::string, std::vector<std::string>>>
434         respData;
435     try
436     {
437         auto resp = bus.call(mapper);
438         resp.read(respData);
439     }
440     catch (const sdbusplus::exception_t&)
441     {
442         // can't do anything without mapper call data
443         throw std::runtime_error("ObjectMapper Call Failure");
444     }
445 
446     if (respData.empty())
447     {
448         // can't do anything without mapper call data
449         throw std::runtime_error("No configuration data available from Mapper");
450     }
451     // create a map of pair of <has pid configuration, ObjectManager path>
452     std::unordered_map<std::string, std::pair<bool, std::string>> owners;
453     // and a map of <path, interface> for sensors
454     std::unordered_map<std::string, std::string> sensors;
455     for (const auto& objectPair : respData)
456     {
457         for (const auto& ownerPair : objectPair.second)
458         {
459             auto& owner = owners[ownerPair.first];
460             for (const std::string& interface : ownerPair.second)
461             {
462                 if (interface == objectManagerInterface)
463                 {
464                     owner.second = objectPair.first;
465                 }
466                 if (interface == pidConfigurationInterface ||
467                     interface == pidZoneConfigurationInterface ||
468                     interface == stepwiseConfigurationInterface)
469                 {
470                     owner.first = true;
471                 }
472                 if (interface == sensorInterface ||
473                     interface == defaultPwmInterface)
474                 {
475                     // we're not interested in pwm sensors, just pwm control
476                     if (interface == sensorInterface &&
477                         objectPair.first.find("pwm") != std::string::npos)
478                     {
479                         continue;
480                     }
481                     sensors[objectPair.first] = interface;
482                 }
483             }
484         }
485     }
486     ManagedObjectType configurations;
487     for (const auto& owner : owners)
488     {
489         // skip if no pid configuration (means probably a sensor)
490         if (!owner.second.first)
491         {
492             continue;
493         }
494         auto endpoint = bus.new_method_call(
495             owner.first.c_str(), owner.second.second.c_str(),
496             "org.freedesktop.DBus.ObjectManager", "GetManagedObjects");
497         ManagedObjectType configuration;
498         try
499         {
500             auto responce = bus.call(endpoint);
501             responce.read(configuration);
502         }
503         catch (const sdbusplus::exception_t&)
504         {
505             // this shouldn't happen, probably means daemon crashed
506             throw std::runtime_error("Error getting managed objects from " +
507                                      owner.first);
508         }
509 
510         for (auto& pathPair : configuration)
511         {
512             if (pathPair.second.find(pidConfigurationInterface) !=
513                     pathPair.second.end() ||
514                 pathPair.second.find(pidZoneConfigurationInterface) !=
515                     pathPair.second.end() ||
516                 pathPair.second.find(stepwiseConfigurationInterface) !=
517                     pathPair.second.end())
518             {
519                 configurations.emplace(pathPair);
520             }
521         }
522     }
523 
524     // remove controllers from config that aren't in the current profile(s)
525     std::vector<std::string> selectedProfiles = getSelectedProfiles(bus);
526     if (selectedProfiles.size())
527     {
528         for (auto pathIt = configurations.begin();
529              pathIt != configurations.end();)
530         {
531             for (auto confIt = pathIt->second.begin();
532                  confIt != pathIt->second.end();)
533             {
534                 auto profilesFind = confIt->second.find("Profiles");
535                 if (profilesFind == confIt->second.end())
536                 {
537                     confIt++;
538                     continue; // if no profiles selected, apply always
539                 }
540                 auto profiles =
541                     std::get<std::vector<std::string>>(profilesFind->second);
542                 if (profiles.empty())
543                 {
544                     confIt++;
545                     continue;
546                 }
547 
548                 bool found = false;
549                 for (const std::string& profile : profiles)
550                 {
551                     if (std::find(selectedProfiles.begin(),
552                                   selectedProfiles.end(),
553                                   profile) != selectedProfiles.end())
554                     {
555                         found = true;
556                         break;
557                     }
558                 }
559                 if (found)
560                 {
561                     confIt++;
562                 }
563                 else
564                 {
565                     confIt = pathIt->second.erase(confIt);
566                 }
567             }
568             if (pathIt->second.empty())
569             {
570                 pathIt = configurations.erase(pathIt);
571             }
572             else
573             {
574                 pathIt++;
575             }
576         }
577     }
578 
579     // On D-Bus, although not necessary,
580     // having the "zoneID" field can still be useful,
581     // as it is used for diagnostic messages,
582     // logging file names, and so on.
583     // Accept optional "ZoneIndex" parameter to explicitly specify.
584     // If not present, or not unique, auto-assign index,
585     // using 0-based numbering, ensuring uniqueness.
586     std::map<std::string, int64_t> foundZones;
587     for (const auto& configuration : configurations)
588     {
589         auto findZone =
590             configuration.second.find(pidZoneConfigurationInterface);
591         if (findZone != configuration.second.end())
592         {
593             const auto& zone = findZone->second;
594 
595             const std::string& name = std::get<std::string>(zone.at("Name"));
596 
597             auto findZoneIndex = zone.find("ZoneIndex");
598             if (findZoneIndex == zone.end())
599             {
600                 continue;
601             }
602 
603             auto ptrZoneIndex = std::get_if<double>(&(findZoneIndex->second));
604             if (!ptrZoneIndex)
605             {
606                 continue;
607             }
608 
609             auto desiredIndex = static_cast<int64_t>(*ptrZoneIndex);
610             auto grantedIndex = setZoneIndex(name, foundZones, desiredIndex);
611             std::cout << "Zone " << name << " is at ZoneIndex " << grantedIndex
612                       << "\n";
613         }
614     }
615 
616     for (const auto& configuration : configurations)
617     {
618         auto findZone =
619             configuration.second.find(pidZoneConfigurationInterface);
620         if (findZone != configuration.second.end())
621         {
622             const auto& zone = findZone->second;
623 
624             const std::string& name = std::get<std::string>(zone.at("Name"));
625 
626             auto index = getZoneIndex(name, foundZones);
627 
628             auto& details = zoneDetailsConfig[index];
629 
630             details.minThermalOutput = std::visit(VariantToDoubleVisitor(),
631                                                   zone.at("MinThermalOutput"));
632 
633             int failsafepercent = 0;
634             auto findFailSafe = zone.find("FailSafePercent");
635             if (findFailSafe != zone.end())
636             {
637                 failsafepercent = std::visit(VariantToDoubleVisitor(),
638                                              zone.at("FailSafePercent"));
639             }
640             details.failsafePercent = failsafepercent;
641 
642             getCycleTimeSetting(zone, index, "CycleIntervalTimeMS",
643                                 details.cycleTime.cycleIntervalTimeMS);
644             getCycleTimeSetting(zone, index, "UpdateThermalsTimeMS",
645                                 details.cycleTime.updateThermalsTimeMS);
646         }
647         auto findBase = configuration.second.find(pidConfigurationInterface);
648         // loop through all the PID configurations and fill out a sensor config
649         if (findBase != configuration.second.end())
650         {
651             const auto& base =
652                 configuration.second.at(pidConfigurationInterface);
653             const std::string pidName =
654                 sensorNameToDbusName(std::get<std::string>(base.at("Name")));
655             const std::string pidClass =
656                 std::get<std::string>(base.at("Class"));
657             const std::vector<std::string>& zones =
658                 std::get<std::vector<std::string>>(base.at("Zones"));
659             for (const std::string& zone : zones)
660             {
661                 auto index = getZoneIndex(zone, foundZones);
662 
663                 conf::PIDConf& conf = zoneConfig[index];
664                 std::vector<std::string> inputSensorNames(
665                     std::get<std::vector<std::string>>(base.at("Inputs")));
666                 std::vector<std::string> outputSensorNames;
667 
668                 // assumption: all fan pids must have at least one output
669                 if (pidClass == "fan")
670                 {
671                     outputSensorNames = std::get<std::vector<std::string>>(
672                         getPIDAttribute(base, "Outputs"));
673                 }
674 
675                 bool unavailableAsFailed = true;
676                 auto findUnavailableAsFailed =
677                     base.find("InputUnavailableAsFailed");
678                 if (findUnavailableAsFailed != base.end())
679                 {
680                     unavailableAsFailed =
681                         std::get<bool>(findUnavailableAsFailed->second);
682                 }
683 
684                 std::vector<SensorInterfaceType> inputSensorInterfaces;
685                 std::vector<SensorInterfaceType> outputSensorInterfaces;
686                 /* populate an interface list for different sensor direction
687                  * types (input,output)
688                  */
689                 /* take the Inputs from the configuration and generate
690                  * a list of dbus descriptors (path, interface).
691                  * Mapping can be many-to-one since an element of Inputs can be
692                  * a regex
693                  */
694                 for (const std::string& sensorName : inputSensorNames)
695                 {
696                     findSensors(sensors, sensorNameToDbusName(sensorName),
697                                 inputSensorInterfaces);
698                 }
699                 for (const std::string& sensorName : outputSensorNames)
700                 {
701                     findSensors(sensors, sensorNameToDbusName(sensorName),
702                                 outputSensorInterfaces);
703                 }
704 
705                 inputSensorNames.clear();
706                 for (const SensorInterfaceType& inputSensorInterface :
707                      inputSensorInterfaces)
708                 {
709                     const std::string& dbusInterface =
710                         inputSensorInterface.second;
711                     const std::string& inputSensorPath =
712                         inputSensorInterface.first;
713 
714                     // Setting timeout to 0 is intentional, as D-Bus passive
715                     // sensor updates are pushed in, not pulled by timer poll.
716                     // Setting ignoreDbusMinMax is intentional, as this
717                     // prevents normalization of values to [0.0, 1.0] range,
718                     // which would mess up the PID loop math.
719                     // All non-fan PID classes should be initialized this way.
720                     // As for why a fan should not use this code path, see
721                     // the ed1dafdf168def37c65bfb7a5efd18d9dbe04727 commit.
722                     if ((pidClass == "temp") || (pidClass == "margin") ||
723                         (pidClass == "power") || (pidClass == "powersum"))
724                     {
725                         std::string inputSensorName =
726                             getSensorNameFromPath(inputSensorPath);
727                         auto& config = sensorConfig[inputSensorName];
728                         inputSensorNames.push_back(inputSensorName);
729                         config.type = pidClass;
730                         config.readPath = inputSensorInterface.first;
731                         config.timeout = 0;
732                         config.ignoreDbusMinMax = true;
733                         config.unavailableAsFailed = unavailableAsFailed;
734                     }
735 
736                     if (dbusInterface != sensorInterface)
737                     {
738                         /* all expected inputs in the configuration are expected
739                          * to be sensor interfaces
740                          */
741                         throw std::runtime_error(
742                             "sensor at dbus path [" + inputSensorPath +
743                             "] has an interface [" + dbusInterface +
744                             "] that does not match the expected interface of " +
745                             sensorInterface);
746                     }
747                 }
748 
749                 /* fan pids need to pair up tach sensors with their pwm
750                  * counterparts
751                  */
752                 if (pidClass == "fan")
753                 {
754                     /* If a PID is a fan there should be either
755                      * (1) one output(pwm) per input(tach)
756                      * OR
757                      * (2) one putput(pwm) for all inputs(tach)
758                      * everything else indicates a bad configuration.
759                      */
760                     bool singlePwm = false;
761                     if (outputSensorInterfaces.size() == 1)
762                     {
763                         /* one pwm, set write paths for all fan sensors to it */
764                         singlePwm = true;
765                     }
766                     else if (inputSensorInterfaces.size() ==
767                              outputSensorInterfaces.size())
768                     {
769                         /* one to one mapping, each fan sensor gets its own pwm
770                          * control */
771                         singlePwm = false;
772                     }
773                     else
774                     {
775                         throw std::runtime_error(
776                             "fan PID has invalid number of Outputs");
777                     }
778                     std::string fanSensorName;
779                     std::string pwmPath;
780                     std::string pwmInterface;
781                     std::string pwmSensorName;
782                     if (singlePwm)
783                     {
784                         /* if just a single output(pwm) is provided then use
785                          * that pwm control path for all the fan sensor write
786                          * path configs
787                          */
788                         pwmPath = outputSensorInterfaces.at(0).first;
789                         pwmInterface = outputSensorInterfaces.at(0).second;
790                     }
791                     for (uint32_t idx = 0; idx < inputSensorInterfaces.size();
792                          idx++)
793                     {
794                         if (!singlePwm)
795                         {
796                             pwmPath = outputSensorInterfaces.at(idx).first;
797                             pwmInterface =
798                                 outputSensorInterfaces.at(idx).second;
799                         }
800                         if (defaultPwmInterface != pwmInterface)
801                         {
802                             throw std::runtime_error(
803                                 "fan pwm control at dbus path [" + pwmPath +
804                                 "] has an interface [" + pwmInterface +
805                                 "] that does not match the expected interface "
806                                 "of " +
807                                 defaultPwmInterface);
808                         }
809                         const std::string& fanPath =
810                             inputSensorInterfaces.at(idx).first;
811                         fanSensorName = getSensorNameFromPath(fanPath);
812                         pwmSensorName = getSensorNameFromPath(pwmPath);
813                         std::string fanPwmIndex = fanSensorName + pwmSensorName;
814                         inputSensorNames.push_back(fanPwmIndex);
815                         auto& fanConfig = sensorConfig[fanPwmIndex];
816                         fanConfig.type = pidClass;
817                         fanConfig.readPath = fanPath;
818                         fanConfig.writePath = pwmPath;
819                         // todo: un-hardcode this if there are fans with
820                         // different ranges
821                         fanConfig.max = 255;
822                         fanConfig.min = 0;
823                     }
824                 }
825                 // if the sensors aren't available in the current state, don't
826                 // add them to the configuration.
827                 if (inputSensorNames.empty())
828                 {
829                     continue;
830                 }
831 
832                 std::string offsetType;
833 
834                 // SetPointOffset is a threshold value to pull from the sensor
835                 // to apply an offset. For upper thresholds this means the
836                 // setpoint is usually negative.
837                 auto findSetpointOffset = base.find("SetPointOffset");
838                 if (findSetpointOffset != base.end())
839                 {
840                     offsetType =
841                         std::get<std::string>(findSetpointOffset->second);
842                     if (std::find(thresholds::types.begin(),
843                                   thresholds::types.end(),
844                                   offsetType) == thresholds::types.end())
845                     {
846                         throw std::runtime_error("Unsupported type: " +
847                                                  offsetType);
848                     }
849                 }
850 
851                 if (offsetType.empty())
852                 {
853                     conf::ControllerInfo& info = conf[pidName];
854                     info.inputs = std::move(inputSensorNames);
855                     populatePidInfo(bus, base, info, nullptr, sensorConfig);
856                 }
857                 else
858                 {
859                     // we have to split up the inputs, as in practice t-control
860                     // values will differ, making setpoints differ
861                     for (const std::string& input : inputSensorNames)
862                     {
863                         conf::ControllerInfo& info = conf[input];
864                         info.inputs.emplace_back(input);
865                         populatePidInfo(bus, base, info, &offsetType,
866                                         sensorConfig);
867                     }
868                 }
869             }
870         }
871         auto findStepwise =
872             configuration.second.find(stepwiseConfigurationInterface);
873         if (findStepwise != configuration.second.end())
874         {
875             const auto& base = findStepwise->second;
876             const std::string pidName =
877                 sensorNameToDbusName(std::get<std::string>(base.at("Name")));
878             const std::vector<std::string>& zones =
879                 std::get<std::vector<std::string>>(base.at("Zones"));
880             for (const std::string& zone : zones)
881             {
882                 auto index = getZoneIndex(zone, foundZones);
883 
884                 conf::PIDConf& conf = zoneConfig[index];
885 
886                 std::vector<std::string> inputs;
887                 std::vector<std::string> sensorNames =
888                     std::get<std::vector<std::string>>(base.at("Inputs"));
889 
890                 bool unavailableAsFailed = true;
891                 auto findUnavailableAsFailed =
892                     base.find("InputUnavailableAsFailed");
893                 if (findUnavailableAsFailed != base.end())
894                 {
895                     unavailableAsFailed =
896                         std::get<bool>(findUnavailableAsFailed->second);
897                 }
898 
899                 bool sensorFound = false;
900                 for (const std::string& sensorName : sensorNames)
901                 {
902                     std::vector<std::pair<std::string, std::string>>
903                         sensorPathIfacePairs;
904                     if (!findSensors(sensors, sensorNameToDbusName(sensorName),
905                                      sensorPathIfacePairs))
906                     {
907                         break;
908                     }
909 
910                     for (const auto& sensorPathIfacePair : sensorPathIfacePairs)
911                     {
912                         size_t idx =
913                             sensorPathIfacePair.first.find_last_of("/") + 1;
914                         std::string shortName =
915                             sensorPathIfacePair.first.substr(idx);
916 
917                         inputs.push_back(shortName);
918                         auto& config = sensorConfig[shortName];
919                         config.readPath = sensorPathIfacePair.first;
920                         config.type = "temp";
921                         config.ignoreDbusMinMax = true;
922                         config.unavailableAsFailed = unavailableAsFailed;
923                         // todo: maybe un-hardcode this if we run into slower
924                         // timeouts with sensors
925 
926                         config.timeout = 0;
927                         sensorFound = true;
928                     }
929                 }
930                 if (!sensorFound)
931                 {
932                     continue;
933                 }
934                 conf::ControllerInfo& info = conf[pidName];
935                 info.inputs = std::move(inputs);
936 
937                 info.type = "stepwise";
938                 info.stepwiseInfo.ts = 1.0; // currently unused
939                 info.stepwiseInfo.positiveHysteresis = 0.0;
940                 info.stepwiseInfo.negativeHysteresis = 0.0;
941                 std::string subtype = std::get<std::string>(base.at("Class"));
942 
943                 info.stepwiseInfo.isCeiling = (subtype == "Ceiling");
944                 auto findPosHyst = base.find("PositiveHysteresis");
945                 auto findNegHyst = base.find("NegativeHysteresis");
946                 if (findPosHyst != base.end())
947                 {
948                     info.stepwiseInfo.positiveHysteresis = std::visit(
949                         VariantToDoubleVisitor(), findPosHyst->second);
950                 }
951                 if (findNegHyst != base.end())
952                 {
953                     info.stepwiseInfo.negativeHysteresis = std::visit(
954                         VariantToDoubleVisitor(), findNegHyst->second);
955                 }
956                 std::vector<double> readings =
957                     std::get<std::vector<double>>(base.at("Reading"));
958                 if (readings.size() > ec::maxStepwisePoints)
959                 {
960                     throw std::invalid_argument("Too many stepwise points.");
961                 }
962                 if (readings.empty())
963                 {
964                     throw std::invalid_argument(
965                         "Must have one stepwise point.");
966                 }
967                 std::copy(readings.begin(), readings.end(),
968                           info.stepwiseInfo.reading);
969                 if (readings.size() < ec::maxStepwisePoints)
970                 {
971                     info.stepwiseInfo.reading[readings.size()] =
972                         std::numeric_limits<double>::quiet_NaN();
973                 }
974                 std::vector<double> outputs =
975                     std::get<std::vector<double>>(base.at("Output"));
976                 if (readings.size() != outputs.size())
977                 {
978                     throw std::invalid_argument(
979                         "Outputs size must match readings");
980                 }
981                 std::copy(outputs.begin(), outputs.end(),
982                           info.stepwiseInfo.output);
983                 if (outputs.size() < ec::maxStepwisePoints)
984                 {
985                     info.stepwiseInfo.output[outputs.size()] =
986                         std::numeric_limits<double>::quiet_NaN();
987                 }
988             }
989         }
990     }
991     if constexpr (pid_control::conf::DEBUG)
992     {
993         debugPrint(sensorConfig, zoneConfig, zoneDetailsConfig);
994     }
995     if (zoneConfig.empty() || zoneDetailsConfig.empty())
996     {
997         std::cerr
998             << "No fan zones, application pausing until new configuration\n";
999         return false;
1000     }
1001     return true;
1002 }
1003 
1004 } // namespace dbus_configuration
1005 } // namespace pid_control
1006