class ELFGenerator:
BUILD_FOLDER = '__build/'
C_SOURCE_FILE = BUILD_FOLDER + 'main.c'
LD_SCRIPT_FILE = BUILD_FOLDER + 'tmp.ld'
INITIAL_C_CODE = '''
typedef unsigned char u8_t;
typedef unsigned short u16_t;
typedef unsigned int u32_t;
typedef void (*handler_void_void_t)(void);
'''
TYPE_TO_BYTE_SIZE = {
'u8_t': 1,
'u16_t': 2,
'u32_t': 4,
'handler_void_void_t': 4, # TODO: handle 64-bit arch
}
PREFIX = 'arm-none-eabi-'
GCC = PREFIX + 'gcc'
OBJCOPY = PREFIX + 'objcopy'
def __init__(self,
fw_path,
target_name=None,
map_address=None,
irq_no=None):
try:
makedirs(ELFGenerator.BUILD_FOLDER)
except FileExistsError:
pass
# TODO: figure out target from target name parameter
self.target_name = target_name
self.target = CortexM(7, map_address, irq_no)
self.fw_path = fw_path
map_address, stack_pointer, entry_point, irq_no = self.target.determine_information(
self.fw_path)
self.entry_point = entry_point
def generate(self, elf_path):
ld = LinkerScript()
ld.set_entry_point('reset', self.entry_point)
mmap = self.target.get_memory_map()
syms = self.target.get_registers()
for m in mmap:
ld.add_memory(*m)
for s in syms:
ld.add_symbol(s[0], s[1])
c_code = self._generate_c_file(syms)
ld_script = str(ld)
open(ELFGenerator.C_SOURCE_FILE, 'w').write(c_code)
open(ELFGenerator.LD_SCRIPT_FILE, 'w').write(ld_script)
self._compile_file(ELFGenerator.C_SOURCE_FILE,
ELFGenerator.LD_SCRIPT_FILE, elf_path)
self._update_section('.vt', self.fw_path, elf_path)
def _generate_c_file(self, structures):
c = ELFGenerator.INITIAL_C_CODE
for s_name, s_address, s_members in structures:
c += 'struct _%s {\n' % s_name
current_address = s_address
for m_name, m_type, m_address, m_description in sorted(
s_members, key=lambda s: s[2]):
# Handle padding here
if current_address != m_address:
c += ' /* 0x%08x */ u8_t __padding__0x%08x_0x%08x[0x%08x];\n' % (
current_address, current_address, m_address,
m_address - current_address)
current_address = m_address
c += ' /* 0x%08x */ %s %s; // %s\n' % (m_address, m_type,
m_name, m_description)
if not m_type in ELFGenerator.TYPE_TO_BYTE_SIZE:
raise Exception('Unknown type used: %s' % m_type)
current_address += ELFGenerator.TYPE_TO_BYTE_SIZE[m_type]
c += '} %s __attribute__((section(".%s")));\n' % (s_name.upper(),
s_name)
return c
def _compile_file(self, source_file, link_script, elf_file):
compiler = [ELFGenerator.GCC]
cflags = [
'-ggdb3', '-nostdlib', '-nostartfiles',
'-mcpu=%s' % self.target_name, '-mthumb'
]
linker_script = [link_script]
source_file = [source_file]
output = ['-o', elf_file]
call(compiler + cflags + linker_script + source_file + linker_script +
output)
def _update_section(self, section_name, raw_file, elf_file):
objcopy = [ELFGenerator.OBJCOPY]
objflags = [
'--update-section',
'%s=%s' % (section_name, raw_file), elf_file
]
call(objcopy + objflags)
