Add otPlatRadioGetReceiveSensitivity() API (#1715)

* Add otPlatRadioGetReceiveSensitivity() API

* Add a new otPlatRadioGetReceiveSensitivity() API to get sensitivity value;

* Use the receive sensitivity value as the noise floor for link metric computation;

* Remove some unused noise floor related functions.

* Add SPINEL_PROP_PHY_RX_SENSITIVITY Spinel/NCP property

examples/drivers/windows/otLwf/radio.c

@@ -814,6 +814,31 @@ void otPlatRadioSetDefaultTxPower(_In_ otInstance *otCtx, int8_t aPower)
     }
 }
 
+int8_t otPlatRadioGetReceiveSensitivity(_In_ otInstance *otCtx)
+{
+    NT_ASSERT(otCtx);
+    PMS_FILTER pFilter = otCtxToFilter(otCtx);
+    NTSTATUS status;
+    int8_t receiveSensitivity;
+
+    status =
+        otLwfCmdGetProp(
+            pFilter,
+            NULL,
+            SPINEL_PROP_PHY_RX_SENSITIVITY,
+            SPINEL_DATATYPE_INT8_S,
+            &receiveSensitivity
+        );
+
+    if (!NT_SUCCESS(status))
+    {
+        LogError(DRIVER_DEFAULT, "Get SPINEL_PROP_PHY_RX_SENSITIVITY, failed, %!STATUS!", status);
+        return -100;  // return default value -100dBm
+    }
+
+    return receiveSensitivity;
+}
+
 inline USHORT getDstShortAddress(const UCHAR *frame)
 {
     return (((USHORT)frame[IEEE802154_DSTADDR_OFFSET + 1]) << 8) | frame[IEEE802154_DSTADDR_OFFSET];

examples/platforms/cc2538/radio.c

@@ -62,6 +62,11 @@ enum
     CC2538_LQI_BIT_MASK = 0x7f,
 };
 
+enum
+{
+    CC2538_RECEIVE_SENSITIVITY = -100, // dBm
+};
+
 static RadioPacket sTransmitFrame;
 static RadioPacket sReceiveFrame;
 static ThreadError sTransmitError;
@@ -793,3 +798,9 @@ void otPlatRadioSetDefaultTxPower(otInstance *aInstance, int8_t aPower)
     (void)aInstance;
     (void)aPower;
 }
+
+int8_t otPlatRadioGetReceiveSensitivity(otInstance *aInstance)
+{
+    (void)aInstance;
+    return CC2538_RECEIVE_SENSITIVITY;
+}

examples/platforms/cc2650/radio.c

@@ -48,6 +48,11 @@
 #include <driverlib/rf_ieee_cmd.h>
 #include <driverlib/chipinfo.h>
 
+enum
+{
+    CC2650_RECEIVE_SENSITIVITY = -100,  // dBm
+};
+
 /* phy state as defined by openthread */
 static volatile cc2650_PhyState sState;
 
@@ -1799,3 +1804,9 @@ void cc2650RadioProcess(otInstance *aInstance)
         sReceiveFrame.mLength = 0;
     }
 }
+
+int8_t otPlatRadioGetReceiveSensitivity(otInstance *aInstance)
+{
+    (void)aInstance;
+    return CC2650_RECEIVE_SENSITIVITY;
+}

examples/platforms/da15000/radio.c

@@ -57,6 +57,11 @@
 #define IEEE802154_ACK_REQUEST          1 << 5
 #define IEEE802154_DSN_OFFSET           2
 
+enum
+{
+    DA15000_RECEIVE_SENSITIVITY = -100,  // dBm
+};
+
 static otInstance *sThreadInstance;
 
 static PhyState    sRadioState = kStateDisabled;
@@ -500,3 +505,8 @@ void FTDF_rcvFrameTransparent(FTDF_DataLength frameLength,
     }
 }
 
+int8_t otPlatRadioGetReceiveSensitivity(otInstance *aInstance)
+{
+    (void)aInstance;
+    return DA15000_RECEIVE_SENSITIVITY;
+}

examples/platforms/efr32/radio.c

@@ -60,6 +60,11 @@ enum
     IEEE802154_DSN_OFFSET                = 2,
 };
 
+enum
+{
+    EFR32_RECEIVE_SENSITIVITY = -100,  // dBm
+};
+
 static uint16_t       sPanId             = 0;
 static uint8_t        sChannel           = 0;
 static bool           sTransmitBusy      = false;
@@ -842,3 +847,9 @@ void otPlatRadioSetDefaultTxPower(otInstance *aInstance, int8_t aPower)
     (void)aInstance;
     RAIL_TxPowerSet(aPower);
 }
+
+int8_t otPlatRadioGetReceiveSensitivity(otInstance *aInstance)
+{
+    (void)aInstance;
+    return EFR32_RECEIVE_SENSITIVITY;
+}

examples/platforms/nrf52840/radio.c

@@ -64,6 +64,11 @@
 #define SHORT_ADDRESS_SIZE    2
 #define EXTENDED_ADDRESS_SIZE 8
 
+enum
+{
+    NRF52840_RECEIVE_SENSITIVITY = -100,  // dBm
+};
+
 static bool sDisabled;
 
 static RadioPacket sReceivedFrames[RADIO_RX_BUFFERS];
@@ -608,3 +613,9 @@ void nrf_drv_radio802154_energy_detected(int8_t result)
 
     setPendingEvent(kPendingEventEnergyDetected);
 }
+
+int8_t otPlatRadioGetReceiveSensitivity(otInstance *aInstance)
+{
+    (void)aInstance;
+    return NRF52840_RECEIVE_SENSITIVITY;
+}

examples/platforms/posix/radio.c

@@ -75,6 +75,11 @@ enum
     IEEE802154_MACCMD_DATA_REQ    = 4,
 };
 
+enum
+{
+    POSIX_RECEIVE_SENSITIVITY = -100,  // dBm
+};
+
 OT_TOOL_PACKED_BEGIN
 struct RadioMessage
 {
@@ -749,3 +754,9 @@ void otPlatRadioSetDefaultTxPower(otInstance *aInstance, int8_t aPower)
     (void)aInstance;
     (void)aPower;
 }
+
+int8_t otPlatRadioGetReceiveSensitivity(otInstance *aInstance)
+{
+    (void)aInstance;
+    return POSIX_RECEIVE_SENSITIVITY;
+}