#!/usr/bin/env python2
  """
  A script to generate FIT image source for rockchip boards
  with ARM Trusted Firmware
  and multiple device trees (given on the command line)
  
  usage: $0 <dt_name> [<dt_name> [<dt_name] ...]
  """
  
  import os
  import sys
  import getopt
  
  # pip install pyelftools
  from elftools.elf.elffile import ELFFile
  from elftools.elf.sections import SymbolTableSection
  from elftools.elf.segments import Segment, InterpSegment, NoteSegment
  
  ELF_SEG_P_TYPE='p_type'
  ELF_SEG_P_PADDR='p_paddr'
  ELF_SEG_P_VADDR='p_vaddr'
  ELF_SEG_P_OFFSET='p_offset'
  ELF_SEG_P_FILESZ='p_filesz'
  ELF_SEG_P_MEMSZ='p_memsz'
  
  DT_HEADER="""/*
   * Copyright (C) 2017 Fuzhou Rockchip Electronics Co., Ltd
   *
   * Minimal dts for a SPL FIT image payload.
   *
   * SPDX-License-Identifier: GPL-2.0+  X11
   */
  /dts-v1/;
  
  / {
  	description = "Configuration to load ATF before U-Boot";
  	#address-cells = <1>;
  
  	images {
  		uboot@1 {
  			description = "U-Boot (64-bit)";
  			data = /incbin/("u-boot-nodtb.bin");
  			type = "standalone";
  			os = "U-Boot";
  			arch = "arm64";
  			compression = "none";
  			load = <0x%08x>;
  		};
  """
  
  DT_IMAGES_NODE_END="""
      };
  """
  
  DT_END="""
  };
  """
  
  def append_atf_node(file, atf_index, phy_addr):
      """
      Append ATF DT node to input FIT dts file.
      """
      data = 'bl31_0x%08x.bin' % phy_addr
      print >> file, '\t\tatf@%d {' % atf_index
      print >> file, '\t\t\tdescription = \"ARM Trusted Firmware\";'
      print >> file, '\t\t\tdata = /incbin/("%s");' % data
      print >> file, '\t\t\ttype = "firmware";'
      print >> file, '\t\t\tarch = "arm64";'
      print >> file, '\t\t\tos = "arm-trusted-firmware";'
      print >> file, '\t\t\tcompression = "none";'
      print >> file, '\t\t\tload = <0x%08x>;' % phy_addr
      if atf_index == 1:
          print >> file, '\t\t\tentry = <0x%08x>;' % phy_addr
      print >> file, '\t\t};'
      print >> file, ''
  
  def append_fdt_node(file, dtbs):
      """
      Append FDT nodes.
      """
      cnt = 1
      for dtb in dtbs:
          dtname = os.path.basename(dtb)
          print >> file, '\t\tfdt@%d {' % cnt
          print >> file, '\t\t\tdescription = "%s";' % dtname
          print >> file, '\t\t\tdata = /incbin/("%s");' % dtb
          print >> file, '\t\t\ttype = "flat_dt";'
          print >> file, '\t\t\tcompression = "none";'
          print >> file, '\t\t};'
          print >> file, ''
          cnt = cnt + 1
  
  def append_conf_section(file, cnt, dtname, atf_cnt):
      print >> file, '\t\tconfig@%d {' % cnt
      print >> file, '\t\t\tdescription = "%s";' % dtname
      print >> file, '\t\t\tfirmware = "atf@1";'
      print >> file, '\t\t\tloadables = "uboot@1",',
      for i in range(1, atf_cnt):
          print >> file, '"atf@%d"' % (i+1),
          if i != (atf_cnt - 1):
              print >> file, ',',
          else:
              print >> file, ';'
      print >> file, '\t\t\tfdt = "fdt@1";'
      print >> file, '\t\t};'
      print >> file, ''
  
  def append_conf_node(file, dtbs, atf_cnt):
      """
      Append configeration nodes.
      """
      cnt = 1
      print >> file, '\tconfigurations {'
      print >> file, '\t\tdefault = "config@1";'
      for dtb in dtbs:
          dtname = os.path.basename(dtb)
          append_conf_section(file, cnt, dtname, atf_cnt)
          cnt = cnt + 1
      print >> file, '\t};'
      print >> file, ''
  
  def generate_atf_fit_dts(fit_file_name, bl31_file_name, uboot_file_name, dtbs_file_name):
      """
      Generate FIT script for ATF image.
      """
      if fit_file_name != sys.stdout:
          fit_file = open(fit_file_name, "wb")
      else:
          fit_file = sys.stdout
  
      num_load_seg = 0
      p_paddr = 0xFFFFFFFF
      with open(uboot_file_name) as uboot_file:
          uboot = ELFFile(uboot_file)
          for i in range(uboot.num_segments()):
              seg = uboot.get_segment(i)
              if ('PT_LOAD' == seg.__getitem__(ELF_SEG_P_TYPE)):
                  p_paddr = seg.__getitem__(ELF_SEG_P_PADDR)
                  num_load_seg = num_load_seg + 1
  
      assert (p_paddr != 0xFFFFFFFF and num_load_seg == 1)
  
      print >> fit_file, DT_HEADER % p_paddr
  
      with open(bl31_file_name) as bl31_file:
          bl31 = ELFFile(bl31_file)
          for i in range(bl31.num_segments()):
              seg = bl31.get_segment(i)
              if ('PT_LOAD' == seg.__getitem__(ELF_SEG_P_TYPE)):
                  paddr = seg.__getitem__(ELF_SEG_P_PADDR)
                  p= seg.__getitem__(ELF_SEG_P_PADDR)
                  append_atf_node(fit_file, i+1, paddr)
      atf_cnt = i+1
      append_fdt_node(fit_file, dtbs_file_name)
      print >> fit_file, '%s' % DT_IMAGES_NODE_END
      append_conf_node(fit_file, dtbs_file_name, atf_cnt)
      print >> fit_file, '%s' % DT_END
  
      if fit_file_name != sys.stdout:
          fit_file.close()
  
  def generate_atf_binary(bl31_file_name):
      with open(bl31_file_name) as bl31_file:
          bl31 = ELFFile(bl31_file)
  
          num = bl31.num_segments()
          for i in range(num):
              seg = bl31.get_segment(i)
              if ('PT_LOAD' == seg.__getitem__(ELF_SEG_P_TYPE)):
                  paddr = seg.__getitem__(ELF_SEG_P_PADDR)
                  file_name = 'bl31_0x%08x.bin' % paddr
                  with open(file_name, "wb") as atf:
                      atf.write(seg.data());
  
  def get_bl31_segments_info(bl31_file_name):
      """
      Get load offset, physical offset, file size
      from bl31 elf file program headers.
      """
      with open(bl31_file_name) as bl31_file:
          bl31 = ELFFile(bl31_file)
  
          num = bl31.num_segments()
          print 'Number of Segments : %d' % bl31.num_segments()
          for i in range(num):
              print 'Segment %d' % i
              seg = bl31.get_segment(i)
              ptype = seg[ELF_SEG_P_TYPE]
              poffset = seg[ELF_SEG_P_OFFSET]
              pmemsz = seg[ELF_SEG_P_MEMSZ]
              pfilesz = seg[ELF_SEG_P_FILESZ]
              print 'type: %s
  filesz: %08x
  memsz: %08x
  offset: %08x' % (ptype, pfilesz, pmemsz, poffset)
              paddr = seg[ELF_SEG_P_PADDR]
              print 'paddr: %08x' % paddr
  
  def main():
      uboot_elf="./u-boot"
      bl31_elf="./bl31.elf"
      FIT_ITS=sys.stdout
  
      opts, args = getopt.getopt(sys.argv[1:], "o:u:b:h")
      for opt, val in opts:
          if opt == "-o":
              FIT_ITS=val
          elif opt == "-u":
              uboot_elf=val
          elif opt == "-b":
              bl31_elf=val
          elif opt == "-h":
              print __doc__
              sys.exit(2)
  
      dtbs = args
      #get_bl31_segments_info("u-boot")
      #get_bl31_segments_info("bl31.elf")
  
      generate_atf_fit_dts(FIT_ITS, bl31_elf, uboot_elf, dtbs)
      generate_atf_binary(bl31_elf);
  
  if __name__ == "__main__":
      main()