Add core voltage for NVIDIA GPU

Author: sergiye

OpenHardwareMonitorLib/Hardware/Gpu/NvidiaGpu.cs

@@ -36,6 +36,7 @@ internal sealed class NvidiaGpu : GenericGpu
     private readonly Sensor _pcieThroughputTx;
     private readonly Sensor[] _powers;
     private readonly Sensor _powerUsage;
+    private readonly Sensor _coreVoltage;
     private readonly Sensor[] _temperatures;
     private readonly uint _thermalSensorsMask;
 
@@ -301,6 +302,15 @@ public NvidiaGpu(int adapterIndex, NvApi.NvPhysicalGpuHandle handle, NvApi.NvDis
             }
         }
 
+        // Voltage
+        var voltageSensor = GetVoltRailsStatus(out status);
+        if (status == NvApi.NvStatus.OK)
+        {
+            _coreVoltage = new Sensor("GPU Core Voltage", 0, SensorType.Voltage, this, settings);
+
+            ActivateSensor(_coreVoltage);
+        }
+
         if (NvidiaML.IsAvailable || NvidiaML.Initialize())
         {
             if (hasBusId)
@@ -608,6 +618,17 @@ public override void Update()
             }
         }
 
+        if (_coreVoltage != null)
+        {
+            var voltageSensor = GetVoltRailsStatus(out status);
+            if (status == NvApi.NvStatus.OK)
+            {
+                var microvolts = ((ulong)voltageSensor.CoreMicrovoltsHigh << 32) | voltageSensor.CoreMicrovolts;
+
+                _coreVoltage.Value = microvolts == 0 ? 0 : microvolts / 1_000_000f;
+            }
+        }
+
         if (_displayHandle != null)
         {
             NvApi.NvMemoryInfo memoryInfo = GetMemoryInfo(out status);
@@ -1032,6 +1053,23 @@ private NvApi.NvThermalSensors GetThermalSensors(uint mask, out NvApi.NvStatus s
         return status == NvApi.NvStatus.OK ? thermalSensors : default;
     }
 
+    private NvApi.NvGpuClientVoltRailsStatus GetVoltRailsStatus(out NvApi.NvStatus status)
+    {
+        if (NvApi.NvAPI_GPU_ClientVoltRailsGetStatus == null)
+        {
+            status = NvApi.NvStatus.Error;
+            return default;
+        }
+
+        var voltRails = new NvApi.NvGpuClientVoltRailsStatus
+        {
+            Version = (uint)NvApi.MAKE_NVAPI_VERSION<NvApi.NvGpuClientVoltRailsStatus>(1),
+        };
+
+        status = NvApi.NvAPI_GPU_ClientVoltRailsGetStatus(_handle, ref voltRails);
+        return status == NvApi.NvStatus.OK ? voltRails : default;
+    }
+
     private NvApi.NvFanCoolersStatus GetFanCoolersStatus(out NvApi.NvStatus status)
     {
         if (NvApi.NvAPI_GPU_ClientFanCoolersGetStatus == null)

OpenHardwareMonitorLib/Interop/NvApi.cs

@@ -45,6 +45,7 @@ internal static class NvApi
     public static NvAPI_GPU_GetUsagesDelegate NvAPI_GPU_GetUsages { get; internal set; }
     public static NvAPI_GPU_SetCoolerLevelsDelegate NvAPI_GPU_SetCoolerLevels { get; internal set; }
     public static NvAPI_GPU_GetThermalSensorsDelegate NvAPI_GPU_GetThermalSensors { get; internal set; }
+    public static NvAPI_GPU_ClientVoltRailsGetStatusDelegate NvAPI_GPU_ClientVoltRailsGetStatus { get; internal set; }
 
     private static NvAPI_GetInterfaceVersionStringDelegate _nvAPI_GetInterfaceVersionString;
     private static NvAPI_GPU_GetFullNameDelegate _nvAPI_GPU_GetFullName;
@@ -89,6 +90,7 @@ public static void Initialize()
             NvAPI_GPU_ClientFanCoolersSetControl = GetDelegate<NvAPI_GPU_ClientFanCoolersSetControlDelegate>(0xA58971A5);
             NvAPI_GPU_ClientPowerTopologyGetStatus = GetDelegate<NvAPI_GPU_ClientPowerTopologyGetStatusDelegate>(0x0EDCF624E);
             NvAPI_GPU_GetThermalSensors = GetDelegate<NvAPI_GPU_GetThermalSensorsDelegate>(0x65FE3AAD);
+            NvAPI_GPU_ClientVoltRailsGetStatus = GetDelegate<NvAPI_GPU_ClientVoltRailsGetStatusDelegate>(0x465F9BCF);
 
             IsAvailable = true;
         }
@@ -157,6 +159,9 @@ public static void Initialize()
     [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
     public delegate NvStatus NvAPI_GPU_SetCoolerLevelsDelegate(NvPhysicalGpuHandle gpuHandle, int coolerIndex, ref NvCoolerLevels NvCoolerLevels);
 
+    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+    public delegate NvStatus NvAPI_GPU_ClientVoltRailsGetStatusDelegate(NvPhysicalGpuHandle gpuHandle, ref NvGpuClientVoltRailsStatus status);
+
     public enum NvFanControlMode : uint
     {
         Auto = 0,
@@ -576,6 +581,17 @@ internal struct NvGpuClockFrequencies
         public NvGpuClockFrequenciesDomain[] Clocks;
     }
 
+    [StructLayout(LayoutKind.Explicit, Size = 0x4C)]
+    internal unsafe struct NvGpuClientVoltRailsStatus
+    {
+        [FieldOffset(0x00)] public uint Version;
+
+        [FieldOffset(0x04)] public fixed uint _reserved[17]; //Unknown
+
+        [FieldOffset(0x28)] public uint CoreMicrovolts;
+        [FieldOffset(0x2C)] public uint CoreMicrovoltsHigh;
+    }
+
     internal enum NvGpuPublicClockId
     {
         Graphics = 0,