hw/scripts/nrfutil: make traits optional and improve device selection

hw/bsp/nordic_pca10059/syscfg.yml

@@ -30,16 +30,16 @@ syscfg.defs:
             tool without debugger.
         value: 0
 
-syscfg.BSP_NRF_SDK_FLASH_LAYOUT:
+syscfg.vals.BSP_NRF_SDK_FLASH_LAYOUT:
     # Change to use Nordic DFU bootloader which is likely to be used
     # when device still has original bootloader
-    NRFUTIL_TRAITS: nordicDfu
+    NRFUTIL_DFU_MODE: 1
+    BOOTUTIL_SINGLE_APPLICATION_SLOT: 1
 
 syscfg.vals:
     MYNEWT_DOWNLOADER: nrfutil
     JLINK_TARGET: nRF52840_xxAA
     PYOCD_TARGET: nrf52840
-    NRFUTIL_TRAITS: jlink
 
 # Enable nRF52840 MCU and common startup code
     MCU_TARGET: nRF52840

hw/scripts/nrfutil.sh

@@ -38,8 +38,14 @@ nrfutil_load () {
         echo "Missing filename"
         exit 1
     fi
+
+    NRF_TRAITS_OPT=""
+    if [ -n "${MYNEWT_VAL_NRFUTIL_TRAITS}" ]; then
+        NRF_TRAITS_OPT="--traits ${MYNEWT_VAL_NRFUTIL_TRAITS}"
+    fi
+
     # If nordicDfu is to be used, create hex file directly from ELF
-    if [ "$MYNEWT_VAL_NRFUTIL_TRAITS" == "nordicDfu" ] ; then
+    if [ "${MYNEWT_VAL_NRFUTIL_DFU_MODE:-0}" -eq 1 ] ; then
         arm-none-eabi-objcopy -O ihex ${ELF_FILE} ${HEX_FILE}
     elif [ ! -f "${FILE_NAME}" ]; then
         # tries stripping current path for readability
@@ -65,36 +71,48 @@ nrfutil_load () {
     fi
 
     ret=0
-    if [ -z ${NRFUTIL_TRAITS} ] ; then
-        if [ -z ${MYNEWT_VAL_NRFUTIL_TRAITS} ] ; then
-            NRFUTIL_TRAITS="--traits jlink"
+    if [ "${MYNEWT_VAL_NRFUTIL_DFU_MODE:-0}" -eq 1 ] ; then
+        ZIP_FILE=${BIN_BASENAME}.zip
+        if [ -n "${MYNEWT_VAL_NRFUTIL_DFU_SN}" ] ; then
+            PORT=$(nrfutil device list --traits nordicDfu | awk -v dfu_sn=$MYNEWT_VAL_NRFUTIL_DFU_SN \
+            'dfu_sn==$1 { sn_match=1 }
+             /^Ports/ { if(sn_match) { print $2; sn_match=0 }}
+             ')
+            if [ -z "$PORT" ] ; then
+              echo "Error: NRFUTIL_DFU_SN does not match any connected board."
+              return 1
+            fi
         else
-            NRFUTIL_TRAITS="--traits ${MYNEWT_VAL_NRFUTIL_TRAITS}"
-            if [ $MYNEWT_VAL_NRFUTIL_TRAITS == "nordicDfu" ] ; then
-                ZIP_FILE=${BIN_BASENAME}.zip
-                PORT=`nrfutil device list --traits nordicDfu | awk '/ports/ { print $2 }'`
-                # TODO: hw-version is probably incorrect for non NRF52 devices
-                nrfutil pkg generate --hw-version 52 --sd-req 0 --application ${HEX_FILE} --application-version 1 ${ZIP_FILE}
-                echo "Downloading" ${ZIP_FILE}
-                nrfutil dfu usb-serial -p ${PORT} --package ${ZIP_FILE}
-                if [ $? -ne 0 ]; then
-                    ret=1
-                fi
+            PORT=$(nrfutil device list --traits nordicDfu | awk '/^Ports/ { print $2 }')
+            PORT_COUNT=$(echo "$PORT" | wc -w)
+            if [ "$PORT_COUNT" -eq 0 ]; then
+                echo "Error: No Nordic DFU devices found."
+                return 1
+            elif [ "$PORT_COUNT" -gt 1 ]; then
+                echo "Error: Found multiple DFU devices. Connect exactly one supported device or add NRFUTIL_DFU_SN to your target."
+                return 1
             fi
         fi
+
+        # TODO: hw-version is probably incorrect for non NRF52 devices
+        nrfutil pkg generate --hw-version 52 --sd-req 0 --application ${HEX_FILE} --application-version 1 ${ZIP_FILE}
+        echo "Downloading" ${ZIP_FILE}
+        nrfutil dfu usb-serial -p ${PORT} --package ${ZIP_FILE}
+        if [ $? -ne 0 ]; then
+            ret=1
+        fi
     fi
 
     if [ -z ${ZIP_FILE} ] ; then
         jlink_sn
 
         echo "Downloading" ${HEX_FILE}
-
-        nrfutil device program --firmware ${HEX_FILE} $SRN_ARG ${NRFUTIL_ARG} ${NRFUTIL_TRAITS} --options chip_erase_mode=ERASE_RANGES_TOUCHED_BY_FIRMWARE
+        nrfutil device program --firmware ${HEX_FILE} ${SRN_ARG} ${NRF_TRAITS_OPT} ${NRFUTIL_ARG} --options chip_erase_mode=ERASE_RANGES_TOUCHED_BY_FIRMWARE
 
         if [ $? -ne 0 ]; then
             ret=1
         else
-            nrfutil device reset $SRN_ARG
+            nrfutil device reset $SRN_ARG ${NRF_TRAITS_OPT}
         fi
     fi
 

hw/scripts/syscfg.yml

@@ -89,11 +89,20 @@ syscfg.defs:
             Some NRF have more then one core. This can specify non-default core
             (i.e. CP_NETWORK for NRF5340).
         value:
+    NRFUTIL_DFU_MODE:
+        description: >
+            Enables firmware upload through nrfutil dfu usb-serial.
+        value:
     NRFUTIL_TRAITS:
         description: >
-            Traits passed to nrfutil command. If not set `jlink` is the default.
-            It can be 'nordicDfu' to upload binary using Nordic SDK DFU
-            bootloader protocol.
+              Optional device traits used by nrfutil to select boards for flashing.
+              When set (e.g. 'jlink'), all connected devices matching this trait
+              will be programmed.
+        value:
+    NRFUTIL_DFU_SN:
+        description: >
+            DFU serial number passed to the nrfutil script.
+            Used to select the target device for firmware upload.
         value:
     MYNEWT_DEBUGGER_SN:
         description: >