work on build tooling to choose a golden bootloader (dubbed, v1.04) and then make a BOOTLOAD.UF2 that actually encompasses latest firmware and the golden bootloader

1 files changed, 41 insertions, 21 deletions

diff --git a/binmaker.py b/binmaker.py
index c48e572..11f3c3a 100644
--- a/binmaker.py
+++ b/binmaker.py
@@ -1,10 +1,19 @@
+# this script takes the compiled firmware (sw/Release/plinkyblack.bin) and
+# bundles it with a bootloader (golden_bootloader.bin) into a single binary file
+# with a version number and filename extracted from the firmware.
+# it USED to read the bootloader from (bootloader/Release/plinkybl.bin) but
+# to avoid unnecessary flashing, it now reads the bootloader from the copy.
+# if you want to update the bootloader, you need to copy it over the golden_bootloader.bin
+# and rerun this script with the magic argument 'bootloader' 
+
 def main():
     # bin file maker
     ver1 = '0'
     ver2 = '0'
     ver3 = '0'
+    bootloader_file = 'golden_bootloader.bin' # "bootloader/Release/plinkybl.bin"
     try:
-        with open("bootloader/Release/plinkybl.bin", "rb") as f1:
+        with open(bootloader_file, "rb") as f1:
             bl_content = f1.read()
         with open("sw/Release/plinkyblack.bin", "rb") as f2:
             app_content = f2.read()
@@ -12,10 +21,16 @@ def main():
         print(f"Failed to open file: {e}")
         exit(2)
     appsize = len(app_content)
-    print(f'{appsize} app, {len(bl_content)} bootloader')
+    bootloader_version = "0000"
+    if chr(bl_content[-3])=='.':
+        bootloader_version = chr(bl_content[-4]) + chr(bl_content[-3]) + chr(bl_content[-2]) + chr(bl_content[-1])
+    print(f'SIZES: {appsize} app, {len(bl_content)} bootloader, bootloader version [{bootloader_version}]')
     # pad bl_content and app_content to reach their sizes
-    bl_content += b'\xff' * (65536 - len(bl_content))
-    app_content += b'\xff' * (1024 * 1024 - 65536 - len(app_content))
+    og_bl_size = len(bl_content)
+    bl_content += b'\xff' * (65536 - len(bl_content) - 4)
+    bl_content += bootloader_version.encode('ascii')
+    assert(len(bl_content) == 65536)
+    app_content += b'\xff' * (1024 * 1024 - 65536 - 2048 - len(app_content)) # leave the last sector empty for the calibration
 
     app = bl_content + app_content
 
@@ -45,28 +60,33 @@ def main():
     uf2args.convert=True
     uf2args.family='STM32L4'
     uf2args.input='sw/Release/plinkyblack.hex'
-    uf2args.base='0x2000'
+    uf2args.base='0x2000' # lol this is wrong, but luckily we were using .hex which has addresses. phew.
+    # the actual base address is 0x08010000 ie 64k into the flash.
     import uf2conv
     uf2conv.uf2conv(uf2args)
 
-    # read 'bootloader/Release/plinkybl.bin', pad to 64k, and write it back
-    try:
-        with open("bootloader/Release/plinkybl.bin", "rb") as f1:
-            bl_content = f1.read()
-        if len(bl_content) < 65536:
-            bl_content += b'\xff' * (65536 - len(bl_content))
-            with open("bootloader/Release/plinkybl.bin", "wb") as f1:
-                f1.write(bl_content)
-            print('padded bootloader to 64k')
-    except IOError as e:
-        print(f"Failed to open file: {e}")
-        exit(2)
-    uf2args.input='bootloader/Release/plinkybl.bin'
+    with open("tempbl.bin", "wb") as f1:
+        f1.write(bl_content)
+    uf2args.input='tempbl.bin'
     uf2args.base='0x20008000'
-    uf2args.output=f"boot{ver1}{ver2}{ver3}.uf2"
+    uf2args.output=f"tempbl.uf2"
     uf2conv.uf2conv(uf2args)
-
-
+    # concatenate the two uf2 files tempbl.uf2 and fname
+    with open(f"BOOTLOAD.UF2", "wb") as f1:
+        with open("tempbl.uf2", "rb") as f2:
+            f1.write(f2.read())
+        with open(fname, "rb") as f2:
+            f1.write(f2.read())
+    # delete temp files
+    import os
+    os.remove("tempbl.bin")
+    os.remove("tempbl.uf2")
+    print("wrote a combiled firmware and bootloader package to BOOTLOAD.UF2")
+    checksum=0
+    # interpret bl_content as a list of 32-bit words
+    for i in range(0, len(bl_content), 4):
+        checksum = (checksum * 23 + int.from_bytes(bl_content[i:i+4], 'little')) & 0xffffffff
+    print(f"bootloader checksum: 0x{checksum:08x} - this should be copied to GOLDEN_CHECKSUM in config.h")
 
 if __name__ == "__main__":
     main()