Working serial bootloader demo

Author: AGlass0fMilk

SerialOTA.cpp

@@ -20,6 +20,7 @@ SerialOTA::ota_error_t SerialOTA::begin(void) {
     uint32_t bytes_collected = 0;
     packet_header_t header = { 0 };
     uint32_t crc;
+    uint8_t tx_byte = 0;
 
     // Initialize the secondary block device
     _update_bd.init();
@@ -29,8 +30,9 @@ SerialOTA::ota_error_t SerialOTA::begin(void) {
 
     _serial.set_blocking(true);
 
-    // Tell the serial bootloader host application to begin :)
-    _serial.write("GO", 2);
+    // Tell the serial bootloader host application to begin
+    tx_byte = 2;
+    _serial.write(&tx_byte, 1);
 
     while(true) {
 
@@ -40,13 +42,8 @@ SerialOTA::ota_error_t SerialOTA::begin(void) {
         // The first bytes will be the header
         memcpy(&header, _payload_buffer, sizeof(packet_header_t));
 
-        // If the sequence number is OTA_DONE_SEQ_NUM we're done!
-        if(header.sequence_num == OTA_DONE_SEQ_NUM) {
-            return OTA_SUCCESS;
-        }
-
         // Check the sequence number
-        if(_current_seq != header.sequence_num) {
+        if((_current_seq != header.sequence_num) && (header.sequence_num != OTA_DONE_SEQ_NUM)) {
             return OTA_OUT_OF_SYNC;
         }
 
@@ -73,5 +70,16 @@ SerialOTA::ota_error_t SerialOTA::begin(void) {
         _current_seq++;
         bytes_collected += header.payload_size;
 
+        // If the sequence number is OTA_DONE_SEQ_NUM we're done!
+        if(header.sequence_num == OTA_DONE_SEQ_NUM) {
+            return OTA_SUCCESS;
+        }
+
+        // Tell the loader script to continue
+        tx_byte = 0;
+        _serial.write(&tx_byte, 1);
+
     }
+
+    return OTA_SUCCESS;
 }

default_bd.cpp

@@ -7,6 +7,8 @@
 
 #include "BlockDevice.h"
 
+#include "SlicingBlockDevice.h"
+
 #if COMPONENT_SPIF
 #include "SPIFBlockDevice.h"
 #endif
@@ -72,7 +74,12 @@ BlockDevice *BlockDevice::get_default_instance()
  * You can override this function to suit your hardware/memory configuration
  * By default it simply returns what is returned by BlockDevice::get_default_instance();
  */
-//mbed::BlockDevice* get_secondary_bd(void) {
-//    return mbed::BlockDevice::get_default_instance();
-//}
+mbed::BlockDevice* get_secondary_bd(void) {
+    // In this case, our flash is much larger than a single image so
+    // slice it into a smaller size, 1MB at the beginning
+
+    mbed::BlockDevice* default_bd = mbed::BlockDevice::get_default_instance();
+    static mbed::SlicingBlockDevice sliced_bd(default_bd, 0x0, 0xDD000);
+    return &sliced_bd;
+}
 

mbed_app.json

@@ -10,15 +10,18 @@
             "target.features_add": ["STORAGE"],
 	    "target.features_remove": ["CRYPTOCELL310"],
 	    "target.macros_remove": ["MBEDTLS_CONFIG_HW_SUPPORT"],
-            "target.components_add": ["QSPIF", "FLASHIAP"]
+            "target.components_add": ["QSPIF", "FLASHIAP"],
+            "mcuboot.max-img-sectors": 256,
+            "qspif.QSPI_MIN_PROG_SIZE": 4
 	},
         "EP_AGORA": {
             "target.device_has_remove": ["ITM"],
             "target.features_add": ["STORAGE"],
             "target.features_remove": ["CRYPTOCELL310"],
             "target.macros_remove": ["MBEDTLS_CONFIG_HW_SUPPORT"],
             "target.components_remove": ["QSPIF"],
-            "target.components_add": ["SPIF", "FLASHIAP"]
+            "target.components_add": ["SPIF", "FLASHIAP"],
+            "mcuboot.max-img-sectors": 256
         }
     }
 }

serial_loader.py

@@ -2,7 +2,9 @@
 import serial
 import argparse
 import struct
-from crc16 import crc16xmodem as crc16
+from crccheck.crc import Crc16CcittFalse
+from time import sleep
+import os
 
 CHUNK_SIZE = 128
 
@@ -14,6 +16,7 @@
 # Payload Size (2-bytes)
 HEADER_FORMAT = "<HH".format(CHUNK_SIZE)
 
+crc16 = Crc16CcittFalse.calc
 
 def read_in_chunks(file_object, chunk_size=256):
     while True:
@@ -33,6 +36,8 @@ def main():
     # Create the OTA serial
     ser = serial.Serial(args.port, 115200, timeout=0.1)
 
+    binary_size = os.path.getsize(args.binary)
+
     # Open the binary
     with open(args.binary, 'rb') as f:
 
@@ -57,24 +62,30 @@ def main():
 
         sequence_num = 0
         for chunk in read_in_chunks(f, CHUNK_SIZE):
-
-            if len(chunk) != CHUNK_SIZE:
+            bytes_written_after = sequence_num * (CHUNK_SIZE+1)
+            if len(chunk) != CHUNK_SIZE or bytes_written_after >= binary_size:
                 sequence_num = 0xFFFF
 
             # Pack the header
             tx_buf = struct.pack(HEADER_FORMAT, sequence_num, len(chunk)) + chunk
 
             # Calculate the CRC16 of the chunk and the header info
+            #print(tx_buf.hex())
+            
             crc = crc16(bytes(tx_buf))
             print("Sending chunk: crc({}), seq num({}), size({})".format(crc, sequence_num, len(chunk)))
 
             tx_buf = struct.pack("<H", crc) + tx_buf
 
             # Encode with COBS
             tx_cobs = cobsr.encode(tx_buf) + bytes([0])
-            print(type(tx_cobs))
-            ser.write(tx_cobs)
-            print(tx_cobs.hex())
+            #print(type(tx_cobs))
+            #ser.write(tx_cobs)
+            #print(tx_cobs.hex())
+
+            for b in tx_cobs:
+                ser.write(bytes([b]))
+                sleep(0.001)
 
             while(True):
                 # Wait until the bootloader is ready
@@ -85,5 +96,12 @@ def main():
 
             sequence_num = sequence_num + 1
 
+        
+    ser.close()
+    ser = serial.Serial(args.port, 9600)
+    while(True):
+        print(ser.readline())
+    
+
 if __name__ == '__main__':
-    main()
+    main()

user_main.cpp

@@ -28,6 +28,10 @@
 #include "drivers/DigitalIn.h"
 #include "SerialCOBS.h"
 
+#include "SlicingBlockDevice.h"
+
+#include "bootutil.h"
+
 #define BOOT_WAIT_TIMEOUT 5s
 
 using namespace std::chrono;
@@ -49,6 +53,7 @@ void mbed_mcuboot_user_init(void) {
 
     // Set up the serial interface
     mbed::BufferedSerial pc(STDIO_UART_TX, STDIO_UART_RX, MBED_CONF_APP_SERIAL_BOOTLOADER_BAUD);
+    //mbed::BufferedSerial pc(P0_3, P0_4, MBED_CONF_APP_SERIAL_BOOTLOADER_BAUD);
 
     // Wait for a specified timeout until just booting
     rtos::Kernel::Clock::duration time_waited = 0ms;
@@ -87,7 +92,9 @@ void mbed_mcuboot_user_init(void) {
 
     SerialOTA::ota_error_t error = ota.begin();
 
-    // TODO - check error?
+    if(error == SerialOTA::OTA_SUCCESS) {
+        boot_set_pending(false);
+    }
 
 #endif // MBED_CONF_APP_SERIAL_BOOTLOADER_ENABLE