--- /dev/null
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright 2026 Free Mobile - Vincent Jardin
+
+"""Regression test for `load sandbox - <addr> <file>`.
+
+Exercises the null_dev_desc_ok dispatch added in
+"fs: dispatch null_dev_desc_ok filesystems before block lookup".
+
+It is the counterpart of test_load_semihosting.py
+"""
+
+import os
+import pytest
+
+
+@pytest.fixture(scope='session')
+def sandbox_fixture(u_boot_config):
+ """Host-staged fixture file read by `load sandbox`."""
+ path = os.path.join(u_boot_config.persistent_data_dir,
+ 'sandbox-fstype.txt')
+ with open(path, 'w', encoding='utf-8') as f:
+ f.write('Das U-Boot\n') # 11 bytes, same as test_hostfs.py / semihosting
+ yield path
+ os.remove(path)
+
+
+@pytest.mark.boardspec('sandbox')
+def test_sandbox_load(ubman, sandbox_fixture):
+ """Run `load sandbox - <addr> <file>` and check the bytes."""
+ response = ubman.run_command(
+ f'load sandbox - $loadaddr {sandbox_fixture}')
+
+ # Fixture is "Das U-Boot\n" (11 bytes).
+ assert '11 bytes read' in response
+
+ # crc32("Das U-Boot\n") -- identical to the semihosting / hostfs checks.
+ response = ubman.run_command('crc32 $loadaddr $filesize')
+ assert '==> 60cfccfc' in response
+
+
+@pytest.mark.boardspec('sandbox')
+def test_sandbox_load_offset(ubman, sandbox_fixture):
+ """Run the [bytes] [pos] variant through the same dispatch."""
+ response = ubman.run_command(
+ f'load sandbox - $loadaddr {sandbox_fixture} 4 6')
+ # bytes=4 pos=6 over "Das U-Boot\n" -> "Boot".
+ assert '4 bytes read' in response
+
+ # crc32("Boot")
+ response = ubman.run_command('crc32 $loadaddr $filesize')
+ assert '==> e6df01fa' in response
--- /dev/null
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright 2026 Free Mobile - Vincent Jardin
+
+"""Regression test for `load semihosting - <addr> <file>`.
+
+Companion to test_hostfs.py: same fixture, same crc32, different
+fstype routing:
+see the doc/usage/cmd/load.rst "Null-block-device interfaces" section.
+"""
+
+import pytest
+
+
+@pytest.mark.buildconfigspec('semihosting')
+def test_semihosting_load(ubman, semihosting_data):
+ """Run `load semihosting - <addr> <file>` and check the bytes."""
+ response = ubman.run_command(
+ f'load semihosting - $loadaddr {semihosting_data}')
+
+ # Fixture is "Das U-Boot\n" (11 bytes).
+ assert '11 bytes read' in response
+
+ # crc32("Das U-Boot\n")
+ response = ubman.run_command('crc32 $loadaddr $filesize')
+ assert '==> 60cfccfc' in response
+
+
+@pytest.mark.buildconfigspec('semihosting')
+def test_semihosting_load_offset(ubman, semihosting_data):
+ """Run the [bytes] [pos] variant through the same dispatch."""
+ response = ubman.run_command(
+ f'load semihosting - $loadaddr {semihosting_data} 4 6')
+ # bytes=4 pos=6 over "Das U-Boot\n" -> "Boot".
+ assert '4 bytes read' in response
+
+ # crc32("Boot")
+ response = ubman.run_command('crc32 $loadaddr $filesize')
+ assert '==> e6df01fa' in response