[uboot] create uboot from github:

repo: https://github.com/u-boot/u-boot
	commit: d80bb749fab53da72c4a0e09b8c2d2aaa3103c91

Change-Id: Ie6434426e1ec15bc08bb1832798e371f3fd5fb29

u-boot-2021.10/tools/binman/cbfs_util_test.py

@@ -0,0 +1,623 @@
+#!/usr/bin/env python
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright 2019 Google LLC
+# Written by Simon Glass <sjg@chromium.org>
+
+"""Tests for cbfs_util
+
+These create and read various CBFSs and compare the results with expected
+values and with cbfstool
+"""
+
+import io
+import os
+import shutil
+import struct
+import tempfile
+import unittest
+
+from binman import cbfs_util
+from binman.cbfs_util import CbfsWriter
+from binman import elf
+from patman import test_util
+from patman import tools
+
+U_BOOT_DATA           = b'1234'
+U_BOOT_DTB_DATA       = b'udtb'
+COMPRESS_DATA         = b'compress xxxxxxxxxxxxxxxxxxxxxx data'
+
+
+class TestCbfs(unittest.TestCase):
+    """Test of cbfs_util classes"""
+    #pylint: disable=W0212
+    @classmethod
+    def setUpClass(cls):
+        # Create a temporary directory for test files
+        cls._indir = tempfile.mkdtemp(prefix='cbfs_util.')
+        tools.SetInputDirs([cls._indir])
+
+        # Set up some useful data files
+        TestCbfs._make_input_file('u-boot.bin', U_BOOT_DATA)
+        TestCbfs._make_input_file('u-boot.dtb', U_BOOT_DTB_DATA)
+        TestCbfs._make_input_file('compress', COMPRESS_DATA)
+
+        # Set up a temporary output directory, used by the tools library when
+        # compressing files
+        tools.PrepareOutputDir(None)
+
+        cls.have_cbfstool = True
+        try:
+            tools.Run('which', 'cbfstool')
+        except:
+            cls.have_cbfstool = False
+
+        cls.have_lz4 = True
+        try:
+            tools.Run('lz4', '--no-frame-crc', '-c',
+                      tools.GetInputFilename('u-boot.bin'), binary=True)
+        except:
+            cls.have_lz4 = False
+
+    @classmethod
+    def tearDownClass(cls):
+        """Remove the temporary input directory and its contents"""
+        if cls._indir:
+            shutil.rmtree(cls._indir)
+        cls._indir = None
+        tools.FinaliseOutputDir()
+
+    @classmethod
+    def _make_input_file(cls, fname, contents):
+        """Create a new test input file, creating directories as needed
+
+        Args:
+            fname: Filename to create
+            contents: File contents to write in to the file
+        Returns:
+            Full pathname of file created
+        """
+        pathname = os.path.join(cls._indir, fname)
+        tools.WriteFile(pathname, contents)
+        return pathname
+
+    def _check_hdr(self, data, size, offset=0, arch=cbfs_util.ARCHITECTURE_X86):
+        """Check that the CBFS has the expected header
+
+        Args:
+            data: Data to check
+            size: Expected ROM size
+            offset: Expected offset to first CBFS file
+            arch: Expected architecture
+
+        Returns:
+            CbfsReader object containing the CBFS
+        """
+        cbfs = cbfs_util.CbfsReader(data)
+        self.assertEqual(cbfs_util.HEADER_MAGIC, cbfs.magic)
+        self.assertEqual(cbfs_util.HEADER_VERSION2, cbfs.version)
+        self.assertEqual(size, cbfs.rom_size)
+        self.assertEqual(0, cbfs.boot_block_size)
+        self.assertEqual(cbfs_util.ENTRY_ALIGN, cbfs.align)
+        self.assertEqual(offset, cbfs.cbfs_offset)
+        self.assertEqual(arch, cbfs.arch)
+        return cbfs
+
+    def _check_uboot(self, cbfs, ftype=cbfs_util.TYPE_RAW, offset=0x38,
+                     data=U_BOOT_DATA, cbfs_offset=None):
+        """Check that the U-Boot file is as expected
+
+        Args:
+            cbfs: CbfsReader object to check
+            ftype: Expected file type
+            offset: Expected offset of file
+            data: Expected data in file
+            cbfs_offset: Expected CBFS offset for file's data
+
+        Returns:
+            CbfsFile object containing the file
+        """
+        self.assertIn('u-boot', cbfs.files)
+        cfile = cbfs.files['u-boot']
+        self.assertEqual('u-boot', cfile.name)
+        self.assertEqual(offset, cfile.offset)
+        if cbfs_offset is not None:
+            self.assertEqual(cbfs_offset, cfile.cbfs_offset)
+        self.assertEqual(data, cfile.data)
+        self.assertEqual(ftype, cfile.ftype)
+        self.assertEqual(cbfs_util.COMPRESS_NONE, cfile.compress)
+        self.assertEqual(len(data), cfile.memlen)
+        return cfile
+
+    def _check_dtb(self, cbfs, offset=0x38, data=U_BOOT_DTB_DATA,
+                   cbfs_offset=None):
+        """Check that the U-Boot dtb file is as expected
+
+        Args:
+            cbfs: CbfsReader object to check
+            offset: Expected offset of file
+            data: Expected data in file
+            cbfs_offset: Expected CBFS offset for file's data
+        """
+        self.assertIn('u-boot-dtb', cbfs.files)
+        cfile = cbfs.files['u-boot-dtb']
+        self.assertEqual('u-boot-dtb', cfile.name)
+        self.assertEqual(offset, cfile.offset)
+        if cbfs_offset is not None:
+            self.assertEqual(cbfs_offset, cfile.cbfs_offset)
+        self.assertEqual(U_BOOT_DTB_DATA, cfile.data)
+        self.assertEqual(cbfs_util.TYPE_RAW, cfile.ftype)
+        self.assertEqual(cbfs_util.COMPRESS_NONE, cfile.compress)
+        self.assertEqual(len(U_BOOT_DTB_DATA), cfile.memlen)
+
+    def _check_raw(self, data, size, offset=0, arch=cbfs_util.ARCHITECTURE_X86):
+        """Check that two raw files are added as expected
+
+        Args:
+            data: Data to check
+            size: Expected ROM size
+            offset: Expected offset to first CBFS file
+            arch: Expected architecture
+        """
+        cbfs = self._check_hdr(data, size, offset=offset, arch=arch)
+        self._check_uboot(cbfs)
+        self._check_dtb(cbfs)
+
+    def _get_expected_cbfs(self, size, arch='x86', compress=None, base=None):
+        """Get the file created by cbfstool for a particular scenario
+
+        Args:
+            size: Size of the CBFS in bytes
+            arch: Architecture of the CBFS, as a string
+            compress: Compression to use, e.g. cbfs_util.COMPRESS_LZMA
+            base: Base address of file, or None to put it anywhere
+
+        Returns:
+            Resulting CBFS file, or None if cbfstool is not available
+        """
+        if not self.have_cbfstool or not self.have_lz4:
+            return None
+        cbfs_fname = os.path.join(self._indir, 'test.cbfs')
+        cbfs_util.cbfstool(cbfs_fname, 'create', '-m', arch, '-s', '%#x' % size)
+        if base:
+            base = [(1 << 32) - size + b for b in base]
+        cbfs_util.cbfstool(cbfs_fname, 'add', '-n', 'u-boot', '-t', 'raw',
+                           '-c', compress and compress[0] or 'none',
+                           '-f', tools.GetInputFilename(
+                               compress and 'compress' or 'u-boot.bin'),
+                           base=base[0] if base else None)
+        cbfs_util.cbfstool(cbfs_fname, 'add', '-n', 'u-boot-dtb', '-t', 'raw',
+                           '-c', compress and compress[1] or 'none',
+                           '-f', tools.GetInputFilename(
+                               compress and 'compress' or 'u-boot.dtb'),
+                           base=base[1] if base else None)
+        return cbfs_fname
+
+    def _compare_expected_cbfs(self, data, cbfstool_fname):
+        """Compare against what cbfstool creates
+
+        This compares what binman creates with what cbfstool creates for what
+        is proportedly the same thing.
+
+        Args:
+            data: CBFS created by binman
+            cbfstool_fname: CBFS created by cbfstool
+        """
+        if not self.have_cbfstool or not self.have_lz4:
+            return
+        expect = tools.ReadFile(cbfstool_fname)
+        if expect != data:
+            tools.WriteFile('/tmp/expect', expect)
+            tools.WriteFile('/tmp/actual', data)
+            print('diff -y <(xxd -g1 /tmp/expect) <(xxd -g1 /tmp/actual) | colordiff')
+            self.fail('cbfstool produced a different result')
+
+    def test_cbfs_functions(self):
+        """Test global functions of cbfs_util"""
+        self.assertEqual(cbfs_util.ARCHITECTURE_X86, cbfs_util.find_arch('x86'))
+        self.assertIsNone(cbfs_util.find_arch('bad-arch'))
+
+        self.assertEqual(cbfs_util.COMPRESS_LZMA, cbfs_util.find_compress('lzma'))
+        self.assertIsNone(cbfs_util.find_compress('bad-comp'))
+
+    def test_cbfstool_failure(self):
+        """Test failure to run cbfstool"""
+        if not self.have_cbfstool:
+            self.skipTest('No cbfstool available')
+        try:
+            # In verbose mode this test fails since stderr is not captured. Fix
+            # this by turning off verbosity.
+            old_verbose = cbfs_util.VERBOSE
+            cbfs_util.VERBOSE = False
+            with test_util.capture_sys_output() as (_stdout, stderr):
+                with self.assertRaises(Exception) as e:
+                    cbfs_util.cbfstool('missing-file', 'bad-command')
+        finally:
+            cbfs_util.VERBOSE = old_verbose
+        self.assertIn('Unknown command', stderr.getvalue())
+        self.assertIn('Failed to run', str(e.exception))
+
+    def test_cbfs_raw(self):
+        """Test base handling of a Coreboot Filesystem (CBFS)"""
+        size = 0xb0
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        cbw.add_file_raw('u-boot-dtb', U_BOOT_DTB_DATA)
+        data = cbw.get_data()
+        self._check_raw(data, size)
+        cbfs_fname = self._get_expected_cbfs(size=size)
+        self._compare_expected_cbfs(data, cbfs_fname)
+
+    def test_cbfs_invalid_file_type(self):
+        """Check handling of an invalid file type when outputiing a CBFS"""
+        size = 0xb0
+        cbw = CbfsWriter(size)
+        cfile = cbw.add_file_raw('u-boot', U_BOOT_DATA)
+
+        # Change the type manually before generating the CBFS, and make sure
+        # that the generator complains
+        cfile.ftype = 0xff
+        with self.assertRaises(ValueError) as e:
+            cbw.get_data()
+        self.assertIn('Unknown type 0xff when writing', str(e.exception))
+
+    def test_cbfs_invalid_file_type_on_read(self):
+        """Check handling of an invalid file type when reading the CBFS"""
+        size = 0xb0
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+
+        data = cbw.get_data()
+
+        # Read in the first file header
+        cbr = cbfs_util.CbfsReader(data, read=False)
+        with io.BytesIO(data) as fd:
+            self.assertTrue(cbr._find_and_read_header(fd, len(data)))
+            pos = fd.tell()
+            hdr_data = fd.read(cbfs_util.FILE_HEADER_LEN)
+            magic, size, ftype, attr, offset = struct.unpack(
+                cbfs_util.FILE_HEADER_FORMAT, hdr_data)
+
+        # Create a new CBFS with a change to the file type
+        ftype = 0xff
+        newdata = data[:pos]
+        newdata += struct.pack(cbfs_util.FILE_HEADER_FORMAT, magic, size, ftype,
+                               attr, offset)
+        newdata += data[pos + cbfs_util.FILE_HEADER_LEN:]
+
+        # Read in this CBFS and make sure that the reader complains
+        with self.assertRaises(ValueError) as e:
+            cbfs_util.CbfsReader(newdata)
+        self.assertIn('Unknown type 0xff when reading', str(e.exception))
+
+    def test_cbfs_no_space(self):
+        """Check handling of running out of space in the CBFS"""
+        size = 0x60
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        with self.assertRaises(ValueError) as e:
+            cbw.get_data()
+        self.assertIn('No space for header', str(e.exception))
+
+    def test_cbfs_no_space_skip(self):
+        """Check handling of running out of space in CBFS with file header"""
+        size = 0x5c
+        cbw = CbfsWriter(size, arch=cbfs_util.ARCHITECTURE_PPC64)
+        cbw._add_fileheader = True
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        with self.assertRaises(ValueError) as e:
+            cbw.get_data()
+        self.assertIn('No space for data before offset', str(e.exception))
+
+    def test_cbfs_no_space_pad(self):
+        """Check handling of running out of space in CBFS with file header"""
+        size = 0x70
+        cbw = CbfsWriter(size)
+        cbw._add_fileheader = True
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        with self.assertRaises(ValueError) as e:
+            cbw.get_data()
+        self.assertIn('No space for data before pad offset', str(e.exception))
+
+    def test_cbfs_bad_header_ptr(self):
+        """Check handling of a bad master-header pointer"""
+        size = 0x70
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        data = cbw.get_data()
+
+        # Add one to the pointer to make it invalid
+        newdata = data[:-4] + struct.pack('<I', cbw._header_offset + 1)
+
+        # We should still be able to find the master header by searching
+        with test_util.capture_sys_output() as (stdout, _stderr):
+            cbfs = cbfs_util.CbfsReader(newdata)
+        self.assertIn('Relative offset seems wrong', stdout.getvalue())
+        self.assertIn('u-boot', cbfs.files)
+        self.assertEqual(size, cbfs.rom_size)
+
+    def test_cbfs_bad_header(self):
+        """Check handling of a bad master header"""
+        size = 0x70
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        data = cbw.get_data()
+
+        # Drop most of the header and try reading the modified CBFS
+        newdata = data[:cbw._header_offset + 4]
+
+        with test_util.capture_sys_output() as (stdout, _stderr):
+            with self.assertRaises(ValueError) as e:
+                cbfs_util.CbfsReader(newdata)
+        self.assertIn('Relative offset seems wrong', stdout.getvalue())
+        self.assertIn('Cannot find master header', str(e.exception))
+
+    def test_cbfs_bad_file_header(self):
+        """Check handling of a bad file header"""
+        size = 0x70
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        data = cbw.get_data()
+
+        # Read in the CBFS master header (only), then stop
+        cbr = cbfs_util.CbfsReader(data, read=False)
+        with io.BytesIO(data) as fd:
+            self.assertTrue(cbr._find_and_read_header(fd, len(data)))
+            pos = fd.tell()
+
+        # Remove all but 4 bytes of the file headerm and try to read the file
+        newdata = data[:pos + 4]
+        with test_util.capture_sys_output() as (stdout, _stderr):
+            with io.BytesIO(newdata) as fd:
+                fd.seek(pos)
+                self.assertEqual(False, cbr._read_next_file(fd))
+        self.assertIn('File header at 0x0 ran out of data', stdout.getvalue())
+
+    def test_cbfs_bad_file_string(self):
+        """Check handling of an incomplete filename string"""
+        size = 0x70
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('16-characters xx', U_BOOT_DATA)
+        data = cbw.get_data()
+
+        # Read in the CBFS master header (only), then stop
+        cbr = cbfs_util.CbfsReader(data, read=False)
+        with io.BytesIO(data) as fd:
+            self.assertTrue(cbr._find_and_read_header(fd, len(data)))
+            pos = fd.tell()
+
+        # Create a new CBFS with only the first 16 bytes of the file name, then
+        # try to read the file
+        newdata = data[:pos + cbfs_util.FILE_HEADER_LEN + 16]
+        with test_util.capture_sys_output() as (stdout, _stderr):
+            with io.BytesIO(newdata) as fd:
+                fd.seek(pos)
+                self.assertEqual(False, cbr._read_next_file(fd))
+        self.assertIn('String at %#x ran out of data' %
+                      cbfs_util.FILE_HEADER_LEN, stdout.getvalue())
+
+    def test_cbfs_debug(self):
+        """Check debug output"""
+        size = 0x70
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        data = cbw.get_data()
+
+        try:
+            cbfs_util.DEBUG = True
+            with test_util.capture_sys_output() as (stdout, _stderr):
+                cbfs_util.CbfsReader(data)
+            self.assertEqual('name u-boot\ndata %s\n' % U_BOOT_DATA,
+                             stdout.getvalue())
+        finally:
+            cbfs_util.DEBUG = False
+
+    def test_cbfs_bad_attribute(self):
+        """Check handling of bad attribute tag"""
+        if not self.have_lz4:
+            self.skipTest('lz4 --no-frame-crc not available')
+        size = 0x140
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', COMPRESS_DATA, None,
+                         compress=cbfs_util.COMPRESS_LZ4)
+        data = cbw.get_data()
+
+        # Search the CBFS for the expected compression tag
+        with io.BytesIO(data) as fd:
+            while True:
+                pos = fd.tell()
+                tag, = struct.unpack('>I', fd.read(4))
+                if tag == cbfs_util.FILE_ATTR_TAG_COMPRESSION:
+                    break
+
+        # Create a new CBFS with the tag changed to something invalid
+        newdata = data[:pos] + struct.pack('>I', 0x123) + data[pos + 4:]
+        with test_util.capture_sys_output() as (stdout, _stderr):
+            cbfs_util.CbfsReader(newdata)
+        self.assertEqual('Unknown attribute tag 123\n', stdout.getvalue())
+
+    def test_cbfs_missing_attribute(self):
+        """Check handling of an incomplete attribute tag"""
+        if not self.have_lz4:
+            self.skipTest('lz4 --no-frame-crc not available')
+        size = 0x140
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', COMPRESS_DATA, None,
+                         compress=cbfs_util.COMPRESS_LZ4)
+        data = cbw.get_data()
+
+        # Read in the CBFS master header (only), then stop
+        cbr = cbfs_util.CbfsReader(data, read=False)
+        with io.BytesIO(data) as fd:
+            self.assertTrue(cbr._find_and_read_header(fd, len(data)))
+            pos = fd.tell()
+
+        # Create a new CBFS with only the first 4 bytes of the compression tag,
+        # then try to read the file
+        tag_pos = pos + cbfs_util.FILE_HEADER_LEN + cbfs_util.FILENAME_ALIGN
+        newdata = data[:tag_pos + 4]
+        with test_util.capture_sys_output() as (stdout, _stderr):
+            with io.BytesIO(newdata) as fd:
+                fd.seek(pos)
+                self.assertEqual(False, cbr._read_next_file(fd))
+        self.assertIn('Attribute tag at %x ran out of data' % tag_pos,
+                      stdout.getvalue())
+
+    def test_cbfs_file_master_header(self):
+        """Check handling of a file containing a master header"""
+        size = 0x100
+        cbw = CbfsWriter(size)
+        cbw._add_fileheader = True
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        data = cbw.get_data()
+
+        cbr = cbfs_util.CbfsReader(data)
+        self.assertIn('u-boot', cbr.files)
+        self.assertEqual(size, cbr.rom_size)
+
+    def test_cbfs_arch(self):
+        """Test on non-x86 architecture"""
+        size = 0x100
+        cbw = CbfsWriter(size, arch=cbfs_util.ARCHITECTURE_PPC64)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        cbw.add_file_raw('u-boot-dtb', U_BOOT_DTB_DATA)
+        data = cbw.get_data()
+        self._check_raw(data, size, offset=0x40,
+                        arch=cbfs_util.ARCHITECTURE_PPC64)
+
+        # Compare against what cbfstool creates
+        cbfs_fname = self._get_expected_cbfs(size=size, arch='ppc64')
+        self._compare_expected_cbfs(data, cbfs_fname)
+
+    def test_cbfs_stage(self):
+        """Tests handling of a Coreboot Filesystem (CBFS)"""
+        if not elf.ELF_TOOLS:
+            self.skipTest('Python elftools not available')
+        elf_fname = os.path.join(self._indir, 'cbfs-stage.elf')
+        elf.MakeElf(elf_fname, U_BOOT_DATA, U_BOOT_DTB_DATA)
+
+        size = 0xb0
+        cbw = CbfsWriter(size)
+        cbw.add_file_stage('u-boot', tools.ReadFile(elf_fname))
+
+        data = cbw.get_data()
+        cbfs = self._check_hdr(data, size)
+        load = 0xfef20000
+        entry = load + 2
+
+        cfile = self._check_uboot(cbfs, cbfs_util.TYPE_STAGE, offset=0x28,
+                                  data=U_BOOT_DATA + U_BOOT_DTB_DATA)
+
+        self.assertEqual(entry, cfile.entry)
+        self.assertEqual(load, cfile.load)
+        self.assertEqual(len(U_BOOT_DATA) + len(U_BOOT_DTB_DATA),
+                         cfile.data_len)
+
+        # Compare against what cbfstool creates
+        if self.have_cbfstool:
+            cbfs_fname = os.path.join(self._indir, 'test.cbfs')
+            cbfs_util.cbfstool(cbfs_fname, 'create', '-m', 'x86', '-s',
+                               '%#x' % size)
+            cbfs_util.cbfstool(cbfs_fname, 'add-stage', '-n', 'u-boot',
+                               '-f', elf_fname)
+            self._compare_expected_cbfs(data, cbfs_fname)
+
+    def test_cbfs_raw_compress(self):
+        """Test base handling of compressing raw files"""
+        if not self.have_lz4:
+            self.skipTest('lz4 --no-frame-crc not available')
+        size = 0x140
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', COMPRESS_DATA, None,
+                         compress=cbfs_util.COMPRESS_LZ4)
+        cbw.add_file_raw('u-boot-dtb', COMPRESS_DATA, None,
+                         compress=cbfs_util.COMPRESS_LZMA)
+        data = cbw.get_data()
+
+        cbfs = self._check_hdr(data, size)
+        self.assertIn('u-boot', cbfs.files)
+        cfile = cbfs.files['u-boot']
+        self.assertEqual(cfile.name, 'u-boot')
+        self.assertEqual(cfile.offset, 56)
+        self.assertEqual(cfile.data, COMPRESS_DATA)
+        self.assertEqual(cfile.ftype, cbfs_util.TYPE_RAW)
+        self.assertEqual(cfile.compress, cbfs_util.COMPRESS_LZ4)
+        self.assertEqual(cfile.memlen, len(COMPRESS_DATA))
+
+        self.assertIn('u-boot-dtb', cbfs.files)
+        cfile = cbfs.files['u-boot-dtb']
+        self.assertEqual(cfile.name, 'u-boot-dtb')
+        self.assertEqual(cfile.offset, 56)
+        self.assertEqual(cfile.data, COMPRESS_DATA)
+        self.assertEqual(cfile.ftype, cbfs_util.TYPE_RAW)
+        self.assertEqual(cfile.compress, cbfs_util.COMPRESS_LZMA)
+        self.assertEqual(cfile.memlen, len(COMPRESS_DATA))
+
+        cbfs_fname = self._get_expected_cbfs(size=size, compress=['lz4', 'lzma'])
+        self._compare_expected_cbfs(data, cbfs_fname)
+
+    def test_cbfs_raw_space(self):
+        """Test files with unused space in the CBFS"""
+        size = 0xf0
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        cbw.add_file_raw('u-boot-dtb', U_BOOT_DTB_DATA)
+        data = cbw.get_data()
+        self._check_raw(data, size)
+        cbfs_fname = self._get_expected_cbfs(size=size)
+        self._compare_expected_cbfs(data, cbfs_fname)
+
+    def test_cbfs_offset(self):
+        """Test a CBFS with files at particular offsets"""
+        size = 0x200
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA, 0x40)
+        cbw.add_file_raw('u-boot-dtb', U_BOOT_DTB_DATA, 0x140)
+
+        data = cbw.get_data()
+        cbfs = self._check_hdr(data, size)
+        self._check_uboot(cbfs, ftype=cbfs_util.TYPE_RAW, offset=0x40,
+                          cbfs_offset=0x40)
+        self._check_dtb(cbfs, offset=0x40, cbfs_offset=0x140)
+
+        cbfs_fname = self._get_expected_cbfs(size=size, base=(0x40, 0x140))
+        self._compare_expected_cbfs(data, cbfs_fname)
+
+    def test_cbfs_invalid_file_type_header(self):
+        """Check handling of an invalid file type when outputting a header"""
+        size = 0xb0
+        cbw = CbfsWriter(size)
+        cfile = cbw.add_file_raw('u-boot', U_BOOT_DATA, 0)
+
+        # Change the type manually before generating the CBFS, and make sure
+        # that the generator complains
+        cfile.ftype = 0xff
+        with self.assertRaises(ValueError) as e:
+            cbw.get_data()
+        self.assertIn('Unknown file type 0xff', str(e.exception))
+
+    def test_cbfs_offset_conflict(self):
+        """Test a CBFS with files that want to overlap"""
+        size = 0x200
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA, 0x40)
+        cbw.add_file_raw('u-boot-dtb', U_BOOT_DTB_DATA, 0x80)
+
+        with self.assertRaises(ValueError) as e:
+            cbw.get_data()
+        self.assertIn('No space for data before pad offset', str(e.exception))
+
+    def test_cbfs_check_offset(self):
+        """Test that we can discover the offset of a file after writing it"""
+        size = 0xb0
+        cbw = CbfsWriter(size)
+        cbw.add_file_raw('u-boot', U_BOOT_DATA)
+        cbw.add_file_raw('u-boot-dtb', U_BOOT_DTB_DATA)
+        data = cbw.get_data()
+
+        cbfs = cbfs_util.CbfsReader(data)
+        self.assertEqual(0x38, cbfs.files['u-boot'].cbfs_offset)
+        self.assertEqual(0x78, cbfs.files['u-boot-dtb'].cbfs_offset)
+
+
+if __name__ == '__main__':
+    unittest.main()