pldm: Enable polling sensors individually

Sensors are polling as part of the polling loop in
sensor manager. There is no provision to read a sensor
individually. Add the provision to read a sensor
using D-Bus infrastructure.

Signed-off-by: Shirish Pargaonkar <Shirish.Pargaonkar@amd.com>

Author: spargaon

platform-mc/manager.hpp

@@ -38,11 +38,14 @@ class Manager : public pldm::MctpDiscoveryHandlerIntf
     explicit Manager(sdeventplus::Event& event, RequesterHandler& handler,
                      pldm::InstanceIdDb& instanceIdDb, const bool verbose) :
         terminusManager(event, handler, instanceIdDb, termini, this,
-                        pldm::BmcMctpEid),
+                        pldm::BmcMctpEid, nullptr),
         platformManager(terminusManager, termini, this),
         sensorManager(event, terminusManager, termini, this),
         eventManager(terminusManager, termini, verbose)
-    {this->verbose = verbose;}
+    {
+       this->verbose = verbose;
+       terminusManager.setSensorManager(&sensorManager);
+    }
 
     /** @brief Helper function to do the actions before discovering terminus
      *
@@ -106,7 +109,23 @@ class Manager : public pldm::MctpDiscoveryHandlerIntf
      */
     void startSensorPolling(pldm_tid_t tid)
     {
-        sensorManager.startPolling(tid);
+         if (termini.contains(tid))
+         {
+             for (auto& sensor : termini[tid]->numericSensors)
+             {
+                 if (sensor)
+                 {
+                    sensor->isReady = true;
+                 }
+             }
+         }
+
+         else
+         {
+             lg2::error("terminii does not contain TID: {TID}.", "TID", tid);
+         }
+
+         sensorManager.startPolling(tid);
     }
 
     /** @brief Helper function to set available state for pldm request (sensor

platform-mc/numeric_sensor.cpp

@@ -2,6 +2,7 @@
 
 #include "common/utils.hpp"
 #include "requester/handler.hpp"
+#include "sensor_manager.hpp"
 
 #include <libpldm/platform.h>
 
@@ -15,6 +16,26 @@ namespace pldm
 namespace platform_mc
 {
 
+double SensorValue::value() const
+{
+    if (this->nSensor.sensorManager && nSensor.isReady && !nSensor.pollPending)
+    {
+        nSensor.pollPending = true;
+
+        nSensor.scope.spawn(
+            [](SensorManager* manager, NumericSensor* sensor) -> exec::task<void> {
+                auto sPtr = std::shared_ptr<NumericSensor>(sensor, [](auto) {});
+                co_await manager->getSensorReading(sPtr);
+                sensor->pollPending = false;
+                co_return;
+            }(nSensor.sensorManager, const_cast<NumericSensor*>(&nSensor))
+        );
+    }
+
+    auto value = ValueIntf::value();
+    return value;
+}
+
 inline bool NumericSensor::createInventoryPath(
     const std::string& associationPath, const std::string& sensorName,
     const uint16_t entityType, const uint16_t entityInstanceNum,
@@ -163,7 +184,9 @@ void NumericSensor::setSensorUnit(uint8_t baseUnit)
 NumericSensor::NumericSensor(
     const pldm_tid_t tid, const bool sensorDisabled,
     std::shared_ptr<pldm_numeric_sensor_value_pdr> pdr, std::string& sensorName,
-    std::string& associationPath) : tid(tid), sensorName(sensorName)
+    std::string& associationPath, SensorManager* sensorManager,
+    exec::async_scope& scoperef) :
+    tid(tid), sensorName(sensorName), sensorManager(sensorManager), scope(scoperef)
 {
     if (!pdr)
     {
@@ -289,7 +312,7 @@ NumericSensor::NumericSensor(
     {
         try
         {
-            valueIntf = std::make_unique<ValueIntf>(bus, path.c_str());
+            valueIntf = std::make_unique<SensorValue>(bus, path.c_str(), *this);
         }
         catch (const sdbusplus::exception_t& e)
         {
@@ -419,8 +442,9 @@ NumericSensor::NumericSensor(
 NumericSensor::NumericSensor(
     const pldm_tid_t tid, const bool sensorDisabled,
     std::shared_ptr<pldm_compact_numeric_sensor_pdr> pdr,
-    std::string& sensorName, std::string& associationPath) :
-    tid(tid), sensorName(sensorName)
+    std::string& sensorName, std::string& associationPath, SensorManager* sensorManager,
+    exec::async_scope& scoperef) :
+    tid(tid), sensorName(sensorName), sensorManager(sensorManager), scope(scoperef)
 {
     if (!pdr)
     {
@@ -532,7 +556,7 @@ NumericSensor::NumericSensor(
     {
         try
         {
-            valueIntf = std::make_unique<ValueIntf>(bus, path.c_str());
+            valueIntf = std::make_unique<SensorValue>(bus, path.c_str(), *this);
         }
         catch (const sdbusplus::exception_t& e)
         {
@@ -698,7 +722,7 @@ void NumericSensor::updateReading(bool available, bool functional, double value)
     double curValue = 0;
     if (!useMetricInterface)
     {
-        curValue = valueIntf->value();
+        curValue = valueIntf->ValueIntf::value();
     }
     else
     {

platform-mc/numeric_sensor.hpp

@@ -49,6 +49,39 @@ using AssociationDefinitionsInft = sdbusplus::server::object_t<
 using EntityIntf = sdbusplus::server::object_t<
     sdbusplus::xyz::openbmc_project::Inventory::Source::PLDM::server::Entity>;
 
+class NumericSensor; // Forward declaration
+class SensorManager; // forward declaration
+
+/** @brief Custom implementation of the Value interface for numeric sensors.
+ *
+ *  This class overrides the standard sdbusplus Value interface to provide
+ *  specialized handling for property access, such as triggering hardware
+ *  polls when the value is requested via D-Bus.
+ */
+class SensorValue : public ValueIntf {
+public:
+    SensorValue(sdbusplus::bus_t& bus, const char* path, pldm::platform_mc::NumericSensor& nS) :
+        ValueIntf(bus, path, ValueIntf::action::emit_object_added),
+        nSensor(nS)
+    {}
+
+    /** @brief Get the sensor reading property.
+     *
+     *  This override triggers an asynchronous hardware poll to update the
+     *  sensor reading when the D-Bus property is accessed (Read-on-Demand).
+     *
+     *  @return The current sensor value stored in the D-Bus interface.
+     */
+    double value() const override;
+
+    double value(double val) override {
+        return ValueIntf::value(val);
+    }
+
+private:
+    pldm::platform_mc::NumericSensor& nSensor;
+};
+
 /**
  * @brief NumericSensor
  *
@@ -60,11 +93,13 @@ class NumericSensor
   public:
     NumericSensor(const pldm_tid_t tid, const bool sensorDisabled,
                   std::shared_ptr<pldm_numeric_sensor_value_pdr> pdr,
-                  std::string& sensorName, std::string& associationPath);
+                  std::string& sensorName, std::string& associationPath,
+                  SensorManager* sensorManager, exec::__scope::async_scope& scope);
 
     NumericSensor(const pldm_tid_t tid, const bool sensorDisabled,
                   std::shared_ptr<pldm_compact_numeric_sensor_pdr> pdr,
-                  std::string& sensorName, std::string& associationPath);
+                  std::string& sensorName, std::string& associationPath,
+                  SensorManager* sensorManager, exec::__scope::async_scope& scope);
 
     ~NumericSensor() {};
 
@@ -247,6 +282,18 @@ class NumericSensor
     /** @brief Sensor Unit */
     SensorUnit sensorUnit;
 
+    /** @brief Sensor Manager to read sensor reading */
+    SensorManager* sensorManager;
+
+    /** @brief Scope to manage the lifetime of asynchronous sensor reading tasks */
+    exec::__scope::async_scope& scope;
+
+    /** @brief Flag to enable Read-on-Demand only after initialization is complete */
+    bool isReady{false};
+
+    /** @brief Flag to prevent multiple concurrent hardware polls for the same sensor */
+    std::atomic<bool> pollPending{false};
+
   private:
     /**
      * @brief Check sensor reading if any threshold has been crossed and update
@@ -275,7 +322,7 @@ class NumericSensor
         const uint16_t containerId);
 
     std::unique_ptr<MetricIntf> metricIntf = nullptr;
-    std::unique_ptr<ValueIntf> valueIntf = nullptr;
+    std::unique_ptr<SensorValue> valueIntf = nullptr;
     std::unique_ptr<ThresholdWarningIntf> thresholdWarningIntf = nullptr;
     std::unique_ptr<ThresholdCriticalIntf> thresholdCriticalIntf = nullptr;
     std::unique_ptr<ThresholdHardShutdownIntf> thresholdHardShutdownIntf =

platform-mc/sensor_manager.hpp

@@ -77,6 +77,13 @@ class SensorManager
         return availableState[tid];
     };
 
+    /** @brief Sending getSensorReading command for the sensor
+     *
+     *  @param[in] sensor - the sensor to be updated
+     *  @return coroutine return_value - PLDM completion code
+     */
+    exec::task<int> getSensorReading(std::shared_ptr<NumericSensor> sensor);
+
   protected:
     /** @brief start a coroutine for polling all sensors.
      */
@@ -89,13 +96,6 @@ class SensorManager
      */
     exec::task<int> doSensorPollingTask(pldm_tid_t tid);
 
-    /** @brief Sending getSensorReading command for the sensor
-     *
-     *  @param[in] sensor - the sensor to be updated
-     *  @return coroutine return_value - PLDM completion code
-     */
-    exec::task<int> getSensorReading(std::shared_ptr<NumericSensor> sensor);
-
     /** @brief Reference to to PLDM daemon's main event loop.
      */
     sdeventplus::Event& event;

platform-mc/terminus.cpp

@@ -2,6 +2,7 @@
 
 #include "dbus_impl_fru.hpp"
 #include "terminus_manager.hpp"
+#include "sensor_manager.hpp"
 
 #include <libpldm/platform.h>
 
@@ -16,11 +17,12 @@ namespace platform_mc
 
 Terminus::Terminus(pldm_tid_t tid, uint64_t supportedTypes,
                    sdeventplus::Event& event,
-                   TerminusManager& terminusManager) :
+                   TerminusManager& terminusManager,
+                   SensorManager* sensorManager) :
     initialized(false), maxBufferSize(PLDM_PLATFORM_EVENT_MSG_MAX_BUFFER_SIZE),
     synchronyConfigurationSupported(0), pollEvent(false), tid(tid),
     supportedTypes(supportedTypes), event(event),
-    terminusManager(terminusManager)
+    terminusManager(terminusManager), sensorManager(sensorManager)
 {}
 
 bool Terminus::doesSupportType(uint8_t type)
@@ -703,7 +705,8 @@ void Terminus::addNumericSensor(
     try
     {
         auto sensor = std::make_shared<NumericSensor>(
-            tid, true, pdr, sensorName, inventoryPath);
+            tid, true, pdr, sensorName, inventoryPath, sensorManager,
+            terminusScope);
         lg2::info("Created NumericSensor {NAME}", "NAME", sensorName);
         numericSensors.emplace_back(sensor);
     }
@@ -876,7 +879,8 @@ void Terminus::addCompactNumericSensor(
     try
     {
         auto sensor = std::make_shared<NumericSensor>(
-            tid, true, pdr, sensorName, inventoryPath);
+            tid, true, pdr, sensorName, inventoryPath, sensorManager,
+            terminusScope);
         lg2::info("Created Compact NumericSensor {NAME}", "NAME", sensorName);
         numericSensors.emplace_back(sensor);
     }

platform-mc/terminus.hpp

@@ -89,6 +89,8 @@ namespace pldm
 namespace platform_mc
 {
 
+class SensorManager; //forward declaration
+
 using ContainerID = uint16_t;
 using EntityInstanceNumber = uint16_t;
 using EntityName = std::string;
@@ -142,7 +144,8 @@ class Terminus
 {
   public:
     Terminus(pldm_tid_t tid, uint64_t supportedPLDMTypes,
-             sdeventplus::Event& event, TerminusManager& terminusManager);
+             sdeventplus::Event& event, TerminusManager& terminusManager,
+             SensorManager* sensorManager);
 
     /** @brief Check if the terminus supports the PLDM type message
      *
@@ -519,6 +522,9 @@ class Terminus
     /** @brief Reference to TerminusManager */
     TerminusManager& terminusManager;
 
+    /** @brief Reference to SensorManager */
+    SensorManager* sensorManager;
+
     /** @brief Numeric Sensor PDR list */
     std::vector<std::shared_ptr<pldm_numeric_sensor_value_pdr>>
         numericSensorPdrs{};

platform-mc/terminus_manager.cpp

@@ -360,7 +360,7 @@ exec::task<int> TerminusManager::initMctpTerminus(const MctpInfo& mctpInfo)
     try
     {
         termini[tid] =
-            std::make_shared<Terminus>(tid, supportedTypes, event, *this);
+            std::make_shared<Terminus>(tid, supportedTypes, event, *this, sensorManager);
     }
     catch (const sdbusplus::exception_t& e)
     {

platform-mc/terminus_manager.hpp

@@ -54,16 +54,24 @@ class TerminusManager
     explicit TerminusManager(
         sdeventplus::Event& event, RequesterHandler& handler,
         pldm::InstanceIdDb& instanceIdDb, TerminiMapper& termini,
-        Manager* manager, mctp_eid_t localEid) :
+        Manager* manager, mctp_eid_t localEid, SensorManager* sensorManager) :
         handler(handler), instanceIdDb(instanceIdDb), termini(termini),
         tidPool(tidPoolSize, false), manager(manager), localEid(localEid),
-        event(event)
+        event(event), sensorManager(sensorManager)
     {
         // DSP0240 v1.1.0 table-8, special value: 0,0xFF = reserved
         tidPool[0] = true;
         tidPool[PLDM_TID_RESERVED] = true;
     }
 
+    /** @brief Set the Sensor Manager pointer
+     *
+     *  @param[in] manager - Pointer to the Sensor Manager
+     */
+    void setSensorManager(SensorManager* manager) {
+         sensorManager = manager;
+    }
+
     /** @brief start a coroutine to discover terminus
      *
      *  @param[in] mctpInfos - list information of the MCTP endpoints
@@ -321,6 +329,9 @@ class TerminusManager
      *  work
      */
     sdeventplus::Event& event;
+
+    /** @brief A Sensor Manager instance **/
+    SensorManager* sensorManager;
 };
 } // namespace platform_mc
 } // namespace pldm