dm: Add tests for the sandbox host driver

Add some unit tests for this.

Signed-off-by: Simon Glass <sjg@chromium.org>

test/py/tests/fs_helper.py

@@ -9,7 +9,7 @@ import re
 import os
 from subprocess import call, check_call, check_output, CalledProcessError
 
-def mk_fs(config, fs_type, size, prefix):
+def mk_fs(config, fs_type, size, prefix, use_src_dir=False):
     """Create a file system volume
 
     Args:
@@ -17,12 +17,14 @@ def mk_fs(config, fs_type, size, prefix):
         fs_type (str): File system type, e.g. 'ext4'
         size (int): Size of file system in bytes
         prefix (str): Prefix string of volume's file name
+        use_src_dir (bool): true to put the file in the source directory
 
     Raises:
         CalledProcessError: if any error occurs when creating the filesystem
     """
     fs_img = f'{prefix}.{fs_type}.img'
-    fs_img = os.path.join(config.persistent_data_dir, fs_img)
+    fs_img = os.path.join(config.source_dir if use_src_dir
+                          else config.persistent_data_dir, fs_img)
 
     if fs_type == 'fat16':
         mkfs_opt = '-F 16'

test/py/tests/test_ut.py

@@ -7,6 +7,7 @@ import os.path
 import pytest
 
 import u_boot_utils
+from tests import fs_helper
 
 def mkdir_cond(dirname):
     """Create a directory if it doesn't already exist
@@ -123,6 +124,11 @@ def test_ut_dm_init(u_boot_console):
         u_boot_utils.run_and_log(
             u_boot_console, f'sfdisk {fn}', stdin=b'type=83')
 
+    fs_helper.mk_fs(u_boot_console.config, 'ext2', 0x200000, '2MB',
+                    use_src_dir=True)
+    fs_helper.mk_fs(u_boot_console.config, 'fat32', 0x100000, '1MB',
+                    use_src_dir=True)
+
 @pytest.mark.buildconfigspec('cmd_bootflow')
 def test_ut_dm_init_bootstd(u_boot_console):
     """Initialise data for bootflow tests"""