Tools: add script to update bootloader

This just sets the param SYS_BL_UPDATE to 1, and then sends the reboot
command. It doesn't do the flashing or building.

Tools/update-bootloader.py

@@ -0,0 +1,82 @@
+#!/usr/bin/env python
+
+from pymavlink import mavutil
+import time
+import struct
+
+connection_string = "/dev/ttyACM0"
+baud_rate = 115200
+
+vehicle = mavutil.mavlink_connection(connection_string, baud=baud_rate)
+
+# Send heartbeat to make PX4 start talking mavlink
+vehicle.mav.heartbeat_send(
+    mavutil.mavlink.MAV_TYPE_GCS, mavutil.mavlink.MAV_AUTOPILOT_INVALID, 0, 0, 0
+)
+time.sleep(1)
+
+# Wait for the heartbeat message to find the system ID
+vehicle.wait_heartbeat()
+
+# Get the system and component IDs
+system_id = vehicle.target_system
+component_id = vehicle.target_component
+
+
+def int_to_float(integer):
+    # Pack the integer as a 32-bit unsigned integer
+    packed_int = struct.pack("I", integer)
+
+    # Unpack the packed integer as a float
+    float_value = struct.unpack("f", packed_int)[0]
+
+    return float_value
+
+
+# Function to set a parameter
+def set_param_int(param_id, value):
+    # Create the PARAM_SET message
+    param_set_msg = vehicle.mav.param_set_encode(
+        system_id,  # target_system
+        component_id,  # target_component
+        param_id.encode("ascii"),  # param_id
+        int_to_float(value),  # param_value
+        mavutil.mavlink.MAV_PARAM_TYPE_INT32,  # param_type
+    )
+
+    # Send the PARAM_SET message
+    vehicle.mav.send(param_set_msg)
+
+    # Wait for an acknowledgment from the vehicle
+    while True:
+        message = vehicle.recv_match(type="PARAM_VALUE", blocking=True)
+        if message.param_id == param_id:
+            print(f"Parameter {param_id} set to {value}")
+            break
+
+
+# Set the SYS_BL_UPDATE parameter to 1
+set_param_int("SYS_BL_UPDATE", 1)
+
+# Give some time for the parameter to be set
+time.sleep(2)
+
+# Send the reboot command
+vehicle.mav.command_long_send(
+    system_id,
+    component_id,
+    mavutil.mavlink.MAV_CMD_PREFLIGHT_REBOOT_SHUTDOWN,  # Command to reboot the system
+    0,  # Confirmation
+    1,  # Param 1 (1 for reboot)
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,  # Unused parameters
+)
+
+print("Reboot command sent")
+
+# Close the connection
+vehicle.close()