Binman Tests

There is some material on writing tests in the main Binman documentation (see Package U-Boot). This short guide is separate so people don’t feel they have to read as much.

Code and output is mostly included verbatim, which makes the doc longer, but avoids its becoming confusing when the output or referenced code changes in the future.

Purpose

The main purpose of tests in Binman is to make sure that Binman actually does what it is supposed to. Various people contribute code, refactoring is done over time, but U-Boot users (developers, SoC vendors, board vendors) rely on Binman producing images which function correctly. Without tests, a one-line change could unintentionally break a corner-case and the problem might not be noticed for months. Debugging an image-generation problem with a board you don’t have can be very hard.

A secondary purpose is productivity. U-Boot contributors are busy and often have too much on their plate. Trying to figure out why their patch broke some other vendor’s workflow can be very time-consuming and frustrating. By building in tests from the start, this is largely avoided. If your change has full test coverage and doesn’t break any test, all is well and no one can complain.

A lessor purpose is to document what Binman actually does. If a test covers a feature, it works. If there is no test coverage, no one can say for sure whether it works in all expected situations, certainly not wihout manual effort.

In fact, strictly speaking it isn’t completely clear what ‘works’ even means in the case where these is no test to cover the code. We are often left guessing as to what the documentation means, what was actually intended, etc.

Finally, code-coverage helps to remove ‘zombie code’, copied from elsewhere because it looks reasonable, but not actually needed. The same situation arises in silicon-chip design, where a part of the chip is not validated. If it isn’t validated, it can be assumed not to work, either now or later, so it is best to remove that logic to avoid it causing problems.

Setting up

Binman tests use various utility programs. Most of these are documented in Building with GCC. But some are SoC-specific. To fetch these, tell Binman to fetch or build any missing tools:

$ binman tool -f missing

When this completes successfully, you can list the tools. You should see something like this:

$ binman tool -l
Name             Version      Description                Path
---------------  -----------  -------------------------  ------------------------------
bootgen          ****** Bootg Xilinx Bootgen             /home/sglass/.binman-tools/bootgen
bzip2            1.0.8        bzip2 compression          /usr/bin/bzip2
cbfstool         unknown      Manipulate CBFS files      /home/sglass/bin/cbfstool
fdt_add_pubkey   unknown      Generate image for U-Boot  /home/sglass/bin/fdt_add_pubkey
fdtgrep          unknown      Grep devicetree files      /home/sglass/bin/fdtgrep
fiptool          v2.11.0(rele Manipulate ATF FIP files   /home/sglass/.binman-tools/fiptool
futility         v0.0.1-9f2e9 Chromium OS firmware utili /home/sglass/.binman-tools/futility
gzip             1.12         gzip compression           /usr/bin/gzip
ifwitool         unknown      Manipulate Intel IFWI file /home/sglass/.binman-tools/ifwitool
lz4              v1.9.4       lz4 compression            /usr/bin/lz4
lzma_alone       9.22 beta    lzma_alone compression     /usr/bin/lzma_alone
lzop             v1.04        lzo compression            /usr/bin/lzop
mkeficapsule     2024.10-rc5- mkeficapsule tool for gene /home/sglass/bin/mkeficapsule
mkimage          2024.10-rc5- Generate image for U-Boot  /home/sglass/bin/mkimage
openssl          3.0.13 30 Ja openssl cryptography toolk /usr/bin/openssl
xz               5.4.5        xz compression             /usr/bin/xz
zstd             v1.5.5       zstd compression           /usr/bin/zstd

The tools are written to ~/.binman-tools so add that to your PATH. It’s fine to have some of the tools elsewhere (e.g. ~/bin) so long as they are up-to-date. This allows you use the version of the tools intended for running tests.

Now you should be able to actually run the tests:

$ binman test
======================== Running binman tests ========================
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
........
----------------------------------------------------------------------
Ran 568 tests in 2.578s

OK

If this doesn’t work, see if you can have some missing tools. Check that the dependencies are all there as above. If it is very slow, try installing concurrencytest so that the tests run in parallel.

The next thing to set up is code coverage, using the -T flag:

$ binman test -T
======================== Running binman tests ========================
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
......................................................................
........
----------------------------------------------------------------------
Ran 568 tests in 17.367s

OK

99%
Name                                                    Stmts   Miss  Cover
---------------------------------------------------------------------------
tools/binman/__init__.py                                    0      0   100%
tools/binman/bintool.py                                   263      0   100%
tools/binman/btool/bootgen.py                              21      0   100%
tools/binman/btool/btool_gzip.py                            5      0   100%
tools/binman/btool/bzip2.py                                 5      0   100%
tools/binman/btool/cbfstool.py                             24      0   100%
tools/binman/btool/cst.py                                  15      4    73%
tools/binman/btool/fdt_add_pubkey.py                       21      0   100%
tools/binman/btool/fdtgrep.py                              26      0   100%
tools/binman/btool/fiptool.py                              19      0   100%
tools/binman/btool/futility.py                             19      0   100%
tools/binman/btool/ifwitool.py                             22      0   100%
tools/binman/btool/lz4.py                                  22      0   100%
tools/binman/btool/lzma_alone.py                           34      0   100%
tools/binman/btool/lzop.py                                  5      0   100%
tools/binman/btool/mkeficapsule.py                         27      0   100%
tools/binman/btool/mkimage.py                              23      0   100%
tools/binman/btool/openssl.py                              42      0   100%
tools/binman/btool/xz.py                                    5      0   100%
tools/binman/btool/zstd.py                                  5      0   100%
tools/binman/cbfs_util.py                                 376      0   100%
tools/binman/cmdline.py                                    90      0   100%
tools/binman/control.py                                   409      0   100%
tools/binman/elf.py                                       241      0   100%
tools/binman/entry.py                                     548      0   100%
tools/binman/etype/alternates_fdt.py                       58      0   100%
tools/binman/etype/atf_bl31.py                              5      0   100%
tools/binman/etype/atf_fip.py                              67      0   100%
tools/binman/etype/blob.py                                 49      0   100%
tools/binman/etype/blob_dtb.py                             46      0   100%
tools/binman/etype/blob_ext.py                              9      0   100%
tools/binman/etype/blob_ext_list.py                        32      0   100%
tools/binman/etype/blob_named_by_arg.py                     9      0   100%
tools/binman/etype/blob_phase.py                           22      0   100%
tools/binman/etype/cbfs.py                                101      0   100%
tools/binman/etype/collection.py                           30      0   100%
tools/binman/etype/cros_ec_rw.py                            5      0   100%
tools/binman/etype/efi_capsule.py                          59      0   100%
tools/binman/etype/efi_empty_capsule.py                    33      0   100%
tools/binman/etype/encrypted.py                            34      0   100%
tools/binman/etype/fdtmap.py                               62      0   100%
tools/binman/etype/files.py                                35      0   100%
tools/binman/etype/fill.py                                 13      0   100%
tools/binman/etype/fit.py                                 311      0   100%
tools/binman/etype/fmap.py                                 37      0   100%
tools/binman/etype/gbb.py                                  37      0   100%
tools/binman/etype/image_header.py                         53      0   100%
tools/binman/etype/intel_cmc.py                             4      0   100%
tools/binman/etype/intel_descriptor.py                     39      0   100%
tools/binman/etype/intel_fit.py                            12      0   100%
tools/binman/etype/intel_fit_ptr.py                        17      0   100%
tools/binman/etype/intel_fsp.py                             4      0   100%
tools/binman/etype/intel_fsp_m.py                           4      0   100%
tools/binman/etype/intel_fsp_s.py                           4      0   100%
tools/binman/etype/intel_fsp_t.py                           4      0   100%
tools/binman/etype/intel_ifwi.py                           67      0   100%
tools/binman/etype/intel_me.py                              4      0   100%
tools/binman/etype/intel_mrc.py                             6      0   100%
tools/binman/etype/intel_refcode.py                         6      0   100%
tools/binman/etype/intel_vbt.py                             4      0   100%
tools/binman/etype/intel_vga.py                             4      0   100%
tools/binman/etype/mkimage.py                              84      0   100%
tools/binman/etype/null.py                                  9      0   100%
tools/binman/etype/nxp_imx8mcst.py                         78     59    24%
tools/binman/etype/nxp_imx8mimage.py                       38      6    84%
tools/binman/etype/opensbi.py                               5      0   100%
tools/binman/etype/powerpc_mpc85xx_bootpg_resetvec.py       6      0   100%
tools/binman/etype/pre_load.py                             76      0   100%
tools/binman/etype/rockchip_tpl.py                          5      0   100%
tools/binman/etype/scp.py                                   5      0   100%
tools/binman/etype/section.py                             418      0   100%
tools/binman/etype/tee_os.py                               31      0   100%
tools/binman/etype/text.py                                 21      0   100%
tools/binman/etype/ti_board_config.py                     139      0   100%
tools/binman/etype/ti_dm.py                                 5      0   100%
tools/binman/etype/ti_secure.py                            65      0   100%
tools/binman/etype/ti_secure_rom.py                       117      0   100%
tools/binman/etype/u_boot.py                                7      0   100%
tools/binman/etype/u_boot_dtb.py                            9      0   100%
tools/binman/etype/u_boot_dtb_with_ucode.py                51      0   100%
tools/binman/etype/u_boot_elf.py                           19      0   100%
tools/binman/etype/u_boot_env.py                           27      0   100%
tools/binman/etype/u_boot_expanded.py                       4      0   100%
tools/binman/etype/u_boot_img.py                            7      0   100%
tools/binman/etype/u_boot_nodtb.py                          7      0   100%
tools/binman/etype/u_boot_spl.py                            8      0   100%
tools/binman/etype/u_boot_spl_bss_pad.py                   14      0   100%
tools/binman/etype/u_boot_spl_dtb.py                        9      0   100%
tools/binman/etype/u_boot_spl_elf.py                        8      0   100%
tools/binman/etype/u_boot_spl_expanded.py                  12      0   100%
tools/binman/etype/u_boot_spl_nodtb.py                      8      0   100%
tools/binman/etype/u_boot_spl_pubkey_dtb.py                32      0   100%
tools/binman/etype/u_boot_spl_with_ucode_ptr.py             8      0   100%
tools/binman/etype/u_boot_tpl.py                            8      0   100%
tools/binman/etype/u_boot_tpl_bss_pad.py                   14      0   100%
tools/binman/etype/u_boot_tpl_dtb.py                        9      0   100%
tools/binman/etype/u_boot_tpl_dtb_with_ucode.py             8      0   100%
tools/binman/etype/u_boot_tpl_elf.py                        8      0   100%
tools/binman/etype/u_boot_tpl_expanded.py                  12      0   100%
tools/binman/etype/u_boot_tpl_nodtb.py                      8      0   100%
tools/binman/etype/u_boot_tpl_with_ucode_ptr.py            12      0   100%
tools/binman/etype/u_boot_ucode.py                         33      0   100%
tools/binman/etype/u_boot_vpl.py                            8      0   100%
tools/binman/etype/u_boot_vpl_bss_pad.py                   14      0   100%
tools/binman/etype/u_boot_vpl_dtb.py                        9      0   100%
tools/binman/etype/u_boot_vpl_elf.py                        8      0   100%
tools/binman/etype/u_boot_vpl_expanded.py                  12      0   100%
tools/binman/etype/u_boot_vpl_nodtb.py                      8      0   100%
tools/binman/etype/u_boot_with_ucode_ptr.py                42      0   100%
tools/binman/etype/vblock.py                               38      0   100%
tools/binman/etype/x86_reset16.py                           7      0   100%
tools/binman/etype/x86_reset16_spl.py                       7      0   100%
tools/binman/etype/x86_reset16_tpl.py                       7      0   100%
tools/binman/etype/x86_start16.py                           7      0   100%
tools/binman/etype/x86_start16_spl.py                       7      0   100%
tools/binman/etype/x86_start16_tpl.py                       7      0   100%
tools/binman/etype/x509_cert.py                            71      0   100%
tools/binman/etype/xilinx_bootgen.py                       72      0   100%
tools/binman/fip_util.py                                  202      0   100%
tools/binman/fmap_util.py                                  49      0   100%
tools/binman/image.py                                     181      0   100%
tools/binman/state.py                                     201      0   100%
---------------------------------------------------------------------------
TOTAL                                                    5954     69    99%

To get a report in 'htmlcov/index.html', type: python3-coverage html
Coverage error: 99%, but should be 100%
ValueError: Test coverage failure

Unfortunately the run failed. As it suggests, create a report:

$ python3-coverage html
Wrote HTML report to htmlcov/index.html

If you open that file in the browser, you can see which files are not reaching 100% and click on them. Here is nxp_imx8mimage.py, for example:

43        # Generate mkimage configuration file similar to imx8mimage.cfg
44        # and pass it to mkimage to generate SPL image for us here.
45        cfg_fname = tools.get_output_filename('nxp.imx8mimage.cfg.%s' % uniq)
46        with open(cfg_fname, 'w') as outf:
47            print('ROM_VERSION v%d' % self.rom_version, file=outf)
48            print('BOOT_FROM %s' % self.boot_from, file=outf)
49            print('LOADER %s %#x' % (input_fname, self.loader_address), file=outf)
50
51        output_fname = tools.get_output_filename(f'cfg-out.{uniq}')
52        args = ['-d', input_fname, '-n', cfg_fname, '-T', 'imx8mimage',
53                output_fname]
54        if self.mkimage.run_cmd(*args) is not None:
55            return tools.read_file(output_fname)
56        else:
57            # Bintool is missing; just use the input data as the output
58 x          self.record_missing_bintool(self.mkimage)
59 x          return data
60
61    def SetImagePos(self, image_pos):
62        # Customized SoC specific SetImagePos which skips the mkimage etype
63        # implementation and removes the 0x48 offset introduced there. That
64        # offset is only used for uImage/fitImage, which is not the case in
65        # here.
66        upto = 0x00
67        for entry in super().GetEntries().values():
68 x          entry.SetOffsetSize(upto, None)
69
70            # Give up if any entries lack a size
71 x          if entry.size is None:
72 x              return
73 x          upto += entry.size
74
75        Entry_section.SetImagePos(self, image_pos)

Most of the file is covered, but the lines marked with x indicate missing coverage. The will show up red in your browser.

What is a test?

A test is a function in ftest.py which uses an image description in tools/binman/test to perform some operations and exercise the code. Some tests are just a few lines; some are more complicated.

Here is a simple test:

def testSimple(self):
    """Test a simple binman with a single file"""
    data = self._DoReadFile('005_simple.dts')
    self.assertEqual(U_BOOT_DATA, data)

This test tells Binman to build an image using the description. Then it checks that the resulting image looks correct. The image description is:

/dts-v1/;

/ {
    #address-cells = <1>;
    #size-cells = <1>;

    binman {
        u-boot {
        };
    };
};

As you will know from the Binman documentation, this says that there is one image and it contains the U-Boot binary. So this test builds an image consisting of a U-Boot binary, then checks that it does indeed have just a U-Boot binary in it.

Test data

Using real binaries (like u-boot.bin) to test Binman would be quite tedious. Every output file would be large and it would be hard to tell by looking at the output (e.g. with a hex dump) if a particular entry contains u-boot.bin or u-boot-spl.bin or something else.

Binman gets around this by using simple placeholders. Here is the placeholder for u-boot.bin:

U_BOOT_DATA           = b'1234'

This is just bytes. So the test above checks that the output image contains these four bytes. This makes verification fast for Binman and very easy for humans.

Even the devicetree is a placeholder:

U_BOOT_DTB_DATA       = b'udtb'

But for some tests you need to use the real devicetree. In that case you can use _DoReadFileRealDtb(). See testUpdateFdtAll() for an example of how to check the devicetree updated by Binman.

Test structure

Each test is designed to test just one thing. Binman tests are named according to what they are testing. Individually they don’t do very much, but as a whole they test every line of code in Binman.

So testSimple() is designed to check that Binman can build the simplest-possible image that isn’t completely empty.

Another type of test is one which checks error-handling, for example:

def testFillNoSize(self):
    """Test for an fill entry type with no size"""
    with self.assertRaises(ValueError) as e:
        self._DoReadFile('070_fill_no_size.dts')
    self.assertIn("'fill' entry is missing properties: size",
                  str(e.exception))

This test deliberately tries to provoke an error. The image description is:

// SPDX-License-Identifier: GPL-2.0+
/dts-v1/;

/ {
    #address-cells = <1>;
    #size-cells = <1>;

    binman {
        size = <16>;
        fill {
            fill-byte = [ff];
        };
    };
};

You can see that there is no size for the ‘fill’ entry, so we would expect Binman to complain. The test checks that it actually does. It also checks the error message produced by Binman. Sometimes you need to add several tests, each with their own broken image description, in order to check all the error cases.

Sometimes you need to capture the console output of Binman, to check it is correct. You can to this with test_util.capture_sys_output(), for example:

with test_util.capture_sys_output() as (_, stderr):
    self._DoTestFile('071_gbb.dts', force_missing_bintools='futility',
                     entry_args=entry_args)
err = stderr.getvalue()
self.assertRegex(err, "Image 'image'.*missing bintools.*: futility")

The test collects the output and checks it with a regular expression. If you need to see the test output (e.g. to debug it), you will have to remove that capture line.

How to add a new test

This section explains the process of writing a new test. It uses an example to help with this, but your code will be different.

Generally you are adding a test because you are adding a new entry type (‘etype’). So start by creating the shortest and simplest image-description you can, which contains the new etype. Put it in a numbered file in tool/binman/test so that it comes last. All the numbers are unique and there are no gaps.

Example from tools/binman/test/339_nxp_imx8.dts:

// SPDX-License-Identifier: GPL-2.0+

/dts-v1/;

/ {
    #address-cells = <1>;
    #size-cells = <1>;

    binman {
        nxp-imx8mimage {
            args;    /* TODO: Needed by mkimage etype superclass */
            nxp,boot-from = "sd";
            nxp,rom-version = <1>;
            nxp,loader-address = <0x10>;
        };
    };
};

Note that you should use tabs in the file, not spaces. You can see that this has been cut down to the bare minimum, just enough to include the etype and the arguments it needs. This is of course not a real image. It will not boot on anything. But that’s fine; we are just trying to test this one etype. Try not to add any other sections and etypes unless they are absolutely essential for your test to work. This helps others too: they don’t need to understand the full complexity of your etype just to read your test.

Then create your test by adding a new function at the end of ftest.py:

def testNxpImx8Image(self):
    """Test that binman can produce an iMX8 image"""
    self._DoTestFile('339_nxp_imx8.dts')

This uses the test file that you created. It doesn’t check anything, it just runs the image description through binman.

Let’s run it:

$ binman test testNxpImx8Image
======================== Running binman tests ========================
.
----------------------------------------------------------------------
Ran 1 test in 0.242s

OK

So the test passes. It doesn’t really do a lot, but it does exercise the etype. The next step is to update it to actually check the output:

def testNxpImx8Image(self):
    """Test that binman can produce an iMX8 image"""
    data = self._DoReadFile('339_nxp_imx8.dts')
    print('data', len(data))

The _DoReadFile() function is documented in the code. It returns the image contents as the first part of a tuple.

Running this we see:

data 2200

So it is producing a little over 8K of data. Your etype will be different, but in any case you can add Python code to check that this data is actually correct, based on your knowledge of your etype. Note that you should not be checking whether the external tools (called ‘bintools’ in Binman) are actually working, since presumably they have their own tests. You just need to check that the image seems reasonable, e.g. is not empty, contains the expected sections, etc.

When your etype does use a bintool, it also needs tests, but generally it will be tested by virtue of the etype test. This is because your etype must call the bintool to create the image. Sometimes you might need to add a test for a bintool error-condition, though.

Finishing code coverage

The objective is to have test-coverage for every line of code that you add to Binman. So how can you tell? First, get a coverage report as described above. Look through the output for any files which are not at 100%. Add more test cases (image descriptions and new functions in ftest.py) until you have covered each line.

In the above example, here are some possible steps:

  1. The first red bit is where the mkimage call returns None. This can be traced to Bintoolmkimage.mkimage() which calls Bintool.run_cmd_result() and None means that mkimage is missing. So the etype has code to handle that case, but it is never used. You can look for other examples of self.mkimage returning None - e.g. Entry_mkimage.BuildSectionData() does this. The clue for finding this is that the nxp-imx8mimage etype is based on Entry_mkimage:

    class Entry_nxp_imx8mimage(Entry_mkimage):
    

    It must be tested somewhere…in this case testMkimage() doesn’t do it, but testMkimageMissing() immediately below that does. So you can create a similar test, e.g.:

    def testNxpImx8ImageMkimageMissing(self):
        """Test that binman can produce an iMX8 image"""
        with test_util.capture_sys_output() as (_, stderr):
            self._DoTestFile('339_nxp_imx8.dts',
                             force_missing_bintools='mkimage')
        err = stderr.getvalue()
        self.assertRegex(err, "Image 'image'.*missing bintools.*: mkimage")
    

    Note that this uses exactly the same image description as the first test. It just checks what happens when the tool is missing. Checking the coverage again, you will see that the first red bit has gone:

    $ binman test -T
    $ python3-coverage html
    
  2. The second red bit is for SetImagePos(). You can see that it is iterating through the sub-entries inside the nxp-imx8mimage entry. In the case of the 339 file, there are no such entries, so this code inside the for() loop isn’t used:

    def SetImagePos(self, image_pos):
     # Customized SoC specific SetImagePos which skips the mkimage etype
     # implementation and removes the 0x48 offset introduced there. That
     # offset is only used for uImage/fitImage, which is not the case in
     # here.
     upto = 0x00
     for entry in super().GetEntries().values():
         entry.SetOffsetSize(upto, None)
    
         # Give up if any entries lack a size
         if entry.size is None:
             return
         upto += entry.size
    
     Entry_section.SetImagePos(self, image_pos)
    

    The solution is to add an entry, e.g. in 340_nxp_imx8_non_empty.dts:

    // SPDX-License-Identifier: GPL-2.0+
    
    /dts-v1/;
    
    / {
        #address-cells = <1>;
        #size-cells = <1>;
    
        binman {
            nxp-imx8mimage {
                args;    /* TODO: Needed by mkimage etype superclass */
                nxp,boot-from = "sd";
                nxp,rom-version = <1>;
                nxp,loader-address = <0x10>;
    
                u-boot {
                };
            };
        };
    };
    

    Now write a little test to use it:

    def testNxpImx8ImageNonEmpty(self):
        """Test that binman can produce an iMX8 image with something in it"""
         data = self._DoReadFile('340_nxp_imx8_non_empty.dts')
         # check data here
    

    With that, the second red bit goes away, because the for() loop is now used.

  3. There is one more red bit left, the return in SetImagePos(). The above effort got the for() loop to be executed, but it doesn’t cover the return. It might have been copied from some other etype, e.g. the mkimage one. See Entry_mkimage.SetImagePos() which contains the code:

    for entry in self.GetEntries().values():
        entry.SetOffsetSize(upto, None)
    
        # Give up if any entries lack a size
        if entry.size is None:
            return
        upto += entry.size
    

    But which test covers that code for mkimage? By figuring that out, you could use a similar technique. One way to find out is to delete the two lines in Entry_mkimage which check for entry.size being None and returning, then see what breaks with binman test:

    ERROR: binman.ftest.TestFunctional.testMkimageCollection (subunit.RemotedTestCase)
    binman.ftest.TestFunctional.testMkimageCollection
    ----------------------------------------------------------------------
    testtools.testresult.real._StringException: Traceback (most recent call last):
    TypeError: unsupported operand type(s) for +=: 'int' and 'NoneType'
    
    ======================================================================
    ERROR: binman.ftest.TestFunctional.testMkimageImage (subunit.RemotedTestCase)
    binman.ftest.TestFunctional.testMkimageImage
    ----------------------------------------------------------------------
    testtools.testresult.real._StringException: Traceback (most recent call last):
    TypeError: unsupported operand type(s) for +=: 'int' and 'NoneType'
    
    ======================================================================
    ERROR: binman.ftest.TestFunctional.testMkimageSpecial (subunit.RemotedTestCase)
    binman.ftest.TestFunctional.testMkimageSpecial
    ----------------------------------------------------------------------
    testtools.testresult.real._StringException: Traceback (most recent call last):
    TypeError: unsupported operand type(s) for +=: 'int' and 'NoneType'
    

    We can verify that you got the right test, by putting the lines back in and getting coverage for just that test:

    binman test -T testMkimageCollection
    python3-coverage html
    

    You will see a lot of red since we are seeing test coverage just for one test, but if you look in mkimage.py at SetImagePos() you will see that the return is covered (i.e. it is marked green).

    Looking at the .dts files for each of these tests, none jumps out as being relevant to our case. It seems that this code just isn’t needed, so the best solution is to delete those two lines from the function:

    def SetImagePos(self, image_pos):
        # Customized SoC specific SetImagePos which skips the mkimage etype
        # implementation and removes the 0x48 offset introduced there. That
        # offset is only used for uImage/fitImage, which is not the case in
        # here.
        upto = 0x00
        for entry in super().GetEntries().values():
            entry.SetOffsetSize(upto, None)
            upto += entry.size
    
        Entry_section.SetImagePos(self, image_pos)
    

We should check the updated code on a real build, to make sure it really isn’t needed, of course.

Now, the test coverage is complete!

If we later discover a case where those lines are needed, we can add the lines back, along with a test for this case.

Getting help

If you are stuck and cannot work out how to add test coverage for your entry type, ask on the U-Boot mailing list, cc Simon Glass <sjg@chromium.org> or on irc sjg1