nvidia-gpu: publish each voltage sensor value update
Voltage sensor values are only updated when the change between the new
and previous reading exceeds the hysteresisPublish threshold. By
default, this threshold is calculated as ((max - min) * 0.0001). Since
this sensor uses theoretical limits for its min/max values, the
resulting hysteresisPublish value is quite large, which prevents updates
from being sent over D-Bus.
This patch sets the max value to a more reasonable upper limit, allowing
sensor value changes to be published to D-Bus as expected.
Tested: Build an image for gb200nvl-obmc machine with the following
patches cherry picked. This patches are needed to enable the mctp stack.
https://gerrit.openbmc.org/c/openbmc/openbmc/+/79422
Power sensor value is being updated.
```
> curl -s -k -u 'root:0penBmc' https://10.137.203.137/redfish/v1/Chassis/NVIDIA_GB200_1/Sensors/voltage_NVIDIA_GB200_GPU_0_Voltage_0
{
"@odata.id": "/redfish/v1/Chassis/NVIDIA_GB200_1/Sensors/voltage_NVIDIA_GB200_GPU_0_Voltage_0",
"@odata.type": "#Sensor.v1_2_0.Sensor",
"Id": "voltage_NVIDIA_GB200_GPU_0_Voltage_0",
"Name": "NVIDIA GB200 GPU 0 Voltage 0",
"Reading": 0.75,
"ReadingRangeMax": 50.0,
"ReadingRangeMin": 0.0,
"ReadingType": "Voltage",
"ReadingUnits": "V",
"Status": {
"Health": "OK",
"State": "Enabled"
}
}%
```
Change-Id: I43190450be82af119fa8d1f4ff0dcb6af9507619
Signed-off-by: Harshit Aghera <haghera@nvidia.com>
diff --git a/src/nvidia-gpu/NvidiaGpuVoltageSensor.cpp b/src/nvidia-gpu/NvidiaGpuVoltageSensor.cpp
index 1ad6052..6fe71e6 100644
--- a/src/nvidia-gpu/NvidiaGpuVoltageSensor.cpp
+++ b/src/nvidia-gpu/NvidiaGpuVoltageSensor.cpp
@@ -32,9 +32,7 @@
using namespace std::literals;
-// Reading from the device is in millivolts and unit set on the dbus is volts.
-static constexpr double gpuVoltageSensorMaxReading =
- std::numeric_limits<uint32_t>::max() / 1000000.0;
+static constexpr double gpuVoltageSensorMaxReading = 50;
static constexpr double gpuVoltageSensorMinReading =
std::numeric_limits<uint32_t>::min();