1  #!/usr/bin/env python3
  2  # Copyright (c) 2014, The Linux Foundation. All rights reserved.
  3  #
  4  # SPDX-License-Identifier: BSD-3-Clause
  5  
  6  import struct
  7  import sys
  8  import os
  9  
 10  """A utility to generate ipq8064 uber SBL..
 11  
 12  The very first blob (aka 'uber SBL') read out of NOR SPI flash by the IPQ8064
 13  maskrom is supposed to be a concatenation of up to three binaries: one to run
 14  on the RPM, another one to run on the AP, and the third one - the actual
 15  coreboot bootblock.
 16  
 17  The uber SBL starts with the combined header descriptor of 80 bytes, with the
 18  first two 4 byte words set to certain values, and the total size of the
 19  payload saved at offsets 28 and 32.
 20  
 21  To generate the uber SBL this utility expects two or three input file names in
 22  the command line, the first file including the described header, and the
 23  following one(s) - in QCA MBN format. This allows to create the uber SBL in
 24  one or two invocations.
 25  
 26  The input files are concatenated together aligned at 256 byte boundary offset
 27  from the combined header. See Usage() below for more details.
 28  
 29  The resulting uber SBL file is prepended by the same combined header adjusted
 30  to reflect the new total file size.
 31  """
 32  
 33  DEFAULT_OUTPUT_FILE_NAME = 'sbl-ro.mbn'
 34  
 35  class NorSbl:
 36      """Object representing the uber SBL."""
 37  
 38      NOR_SBL1_HEADER    = '<II72s'
 39      NOR_SBL1_HEADER_SZ = struct.calcsize(NOR_SBL1_HEADER)
 40      ALIGNMENT          = 256    # Make sure this == UBER_SBL_PAD_SIZE
 41      NOR_CODE_WORD      = 0x844bdcd1
 42      MAGIC_NUM          = 0x73d71034
 43  
 44      def __init__(self, sbl1, verbose):
 45          """Initialize the object and verify the first file in the sequence.
 46  
 47          Args:
 48            sbl1: string, the name of the first out of the three input blobs,
 49                  must be prepended by the combined header.
 50            verbose: boolean, if True - print debug information on the console.
 51          """
 52          self.verbose = verbose
 53          self.mbn_file_names = []
 54          if self.verbose:
 55              print('Reading ' + sbl1)
 56  
 57          try:
 58              self.sbl1 = open(sbl1, 'rb').read()
 59          except IOError as e:
 60              print('I/O error({0}): {1}'.format(e.errno, e.strerror))
 61              raise
 62  
 63          (codeword, magic,  _) = struct.unpack_from(
 64              self.NOR_SBL1_HEADER, self.sbl1)
 65  
 66          if codeword != self.NOR_CODE_WORD:
 67              print('\n\nError: Unexpected Codeword!')
 68              print('Codeword    : ' + ('0x%x' % self.NOR_CODE_WORD) + \
 69                  ' != ' + ('0x%x' % codeword))
 70              sys.exit(-1)
 71  
 72          if magic != self.MAGIC_NUM:
 73              print('\n\nError: Unexpected Magic!')
 74              print('Magic    : ' + ('0x%x' % self.MAGIC_NUM) + \
 75                  ' != ' + ('0x%x' % magic))
 76              sys.exit(-1)
 77  
 78      def Append(self, src):
 79          """Add a file to the list of files to be concatenated"""
 80          self.mbn_file_names.append(src)
 81  
 82      def PadOutput(self, outfile, size):
 83          """Pad output file to the required alignment.
 84  
 85          Adds 0xff to the passed in file to get its size to the ALIGNMENT
 86          boundary.
 87  
 88          Args:
 89            outfile: file handle of the file to be padded
 90            size: int, current size of the file
 91  
 92         Returns number of bytes in the added padding.
 93         """
 94  
 95          # Is padding needed?
 96          overflow = size % self.ALIGNMENT
 97          if overflow:
 98              pad_size = self.ALIGNMENT - overflow
 99              pad = b'\377' * pad_size
100              outfile.write(pad)
101              if self.verbose:
102                  print('Added %d byte padding' % pad_size)
103              return pad_size
104          return 0
105  
106      def Create(self, out_file_name):
107          """Create the uber SBL.
108  
109          Concatenate input files with the appropriate padding and update the
110          combined header to reflect the new blob size.
111  
112          Args:
113            out_file_name: string, name of the file to save the generated uber
114                           SBL in.
115         """
116          outfile = open(out_file_name, 'wb')
117          total_size = len(self.sbl1) - self.NOR_SBL1_HEADER_SZ
118          outfile.write(self.sbl1)
119  
120          for mbn_file_name in self.mbn_file_names:
121              total_size += self.PadOutput(outfile, total_size)
122              mbn_file_data = open(mbn_file_name, 'rb').read()
123              outfile.write(mbn_file_data)
124              if self.verbose:
125                  print('Added %s (%d bytes)' % (mbn_file_name,
126                                                 len(mbn_file_data)))
127              total_size += len(mbn_file_data)
128  
129          outfile.seek(28)
130          outfile.write(struct.pack('<I', total_size))
131          outfile.write(struct.pack('<I', total_size))
132  
133  
134  def Usage(v):
135      print('%s: [-v] [-h] [-o Output MBN] sbl1 sbl2 [bootblock]' % (
136          os.path.basename(sys.argv[0])))
137      print()
138      print('Concatenates up to three mbn files: two SBLs and a coreboot bootblock')
139      print('    -h This message')
140      print('    -v verbose')
141      print('    -o Output file name, (default: %s)\n' % DEFAULT_OUTPUT_FILE_NAME)
142      sys.exit(v)
143  
144  def main():
145      verbose = 0
146      mbn_output = DEFAULT_OUTPUT_FILE_NAME
147      i = 0
148  
149      while i < (len(sys.argv) - 1):
150          i += 1
151          if (sys.argv[i] == '-h'):
152              Usage(0)    # doesn't return
153  
154          if (sys.argv[i] == '-o'):
155              mbn_output = sys.argv[i + 1]
156              i += 1
157              continue
158  
159          if (sys.argv[i] == '-v'):
160              verbose = 1
161              continue
162  
163          break
164  
165      argv = sys.argv[i:]
166      if len(argv) < 2 or len(argv) > 3:
167          Usage(-1)
168  
169      nsbl = NorSbl(argv[0], verbose)
170  
171      for mbnf in argv[1:]:
172          nsbl.Append(mbnf)
173  
174      nsbl.Create(mbn_output)
175  
176  if __name__ == '__main__':
177      main()