Nitin Shukla / LED_Demo

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Dependencies:   MAX44000 nexpaq_mdk

Fork of LED_Demo by Maxim nexpaq

mbd_os/tools/patch.py@1:55a6170b404f, 2016-09-17 (annotated)

Committer:
nexpaq
Date:
Sat Sep 17 16:32:05 2016 +0000
Revision:
1:55a6170b404f
checking in for sharing

Who changed what in which revision?

UserRevisionLine numberNew contents of line
nexpaq 1:55a6170b404f 1 """
nexpaq 1:55a6170b404f 2 mbed SDK
nexpaq 1:55a6170b404f 3 Copyright (c) 2011-2013 ARM Limited
nexpaq 1:55a6170b404f 4
nexpaq 1:55a6170b404f 5 Licensed under the Apache License, Version 2.0 (the "License");
nexpaq 1:55a6170b404f 6 you may not use this file except in compliance with the License.
nexpaq 1:55a6170b404f 7 You may obtain a copy of the License at
nexpaq 1:55a6170b404f 8
nexpaq 1:55a6170b404f 9 http://www.apache.org/licenses/LICENSE-2.0
nexpaq 1:55a6170b404f 10
nexpaq 1:55a6170b404f 11 Unless required by applicable law or agreed to in writing, software
nexpaq 1:55a6170b404f 12 distributed under the License is distributed on an "AS IS" BASIS,
nexpaq 1:55a6170b404f 13 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
nexpaq 1:55a6170b404f 14 See the License for the specific language governing permissions and
nexpaq 1:55a6170b404f 15 limitations under the License.
nexpaq 1:55a6170b404f 16
nexpaq 1:55a6170b404f 17
nexpaq 1:55a6170b404f 18 http://www.nxp.com/documents/user_manual/UM10360.pdf
nexpaq 1:55a6170b404f 19
nexpaq 1:55a6170b404f 20 32.3.1.1 Criterion for Valid User Code
nexpaq 1:55a6170b404f 21 The reserved Cortex-M3 exception vector location 7 (offset 0x1C in the vector table)
nexpaq 1:55a6170b404f 22 should contain the 2's complement of the check-sum of table entries 0 through 6. This
nexpaq 1:55a6170b404f 23 causes the checksum of the first 8 table entries to be 0. The boot loader code checksums
nexpaq 1:55a6170b404f 24 the first 8 locations in sector 0 of the flash. If the result is 0, then execution control is
nexpaq 1:55a6170b404f 25 transferred to the user code.
nexpaq 1:55a6170b404f 26 """
nexpaq 1:55a6170b404f 27 from struct import unpack, pack
nexpaq 1:55a6170b404f 28
nexpaq 1:55a6170b404f 29
nexpaq 1:55a6170b404f 30 def patch(bin_path):
nexpaq 1:55a6170b404f 31 with open(bin_path, 'r+b') as bin:
nexpaq 1:55a6170b404f 32 # Read entries 0 through 6 (Little Endian 32bits words)
nexpaq 1:55a6170b404f 33 vector = [unpack('<I', bin.read(4))[0] for _ in range(7)]
nexpaq 1:55a6170b404f 34
nexpaq 1:55a6170b404f 35 # location 7 (offset 0x1C in the vector table) should contain the 2's
nexpaq 1:55a6170b404f 36 # complement of the check-sum of table entries 0 through 6
nexpaq 1:55a6170b404f 37 bin.seek(0x1C)
nexpaq 1:55a6170b404f 38 bin.write(pack('<I', (~sum(vector) + 1) & 0xFFFFFFFF))
nexpaq 1:55a6170b404f 39
nexpaq 1:55a6170b404f 40
nexpaq 1:55a6170b404f 41 def is_patched(bin_path):
nexpaq 1:55a6170b404f 42 with open(bin_path, 'rb') as bin:
nexpaq 1:55a6170b404f 43 # The checksum of the first 8 table entries should be 0
nexpaq 1:55a6170b404f 44 return (sum([unpack('<I', bin.read(4))[0] for _ in range(8)]) & 0xFFFFFFFF) == 0
nexpaq 1:55a6170b404f 45
nexpaq 1:55a6170b404f 46
nexpaq 1:55a6170b404f 47 if __name__ == '__main__':
nexpaq 1:55a6170b404f 48 bin_path = "C:/Users/emimon01/releases/emilmont/build/test/LPC1768/ARM/MBED_A1/basic.bin"
nexpaq 1:55a6170b404f 49 patch(bin_path)
nexpaq 1:55a6170b404f 50 assert is_patched(bin_path), "The file is not patched"