test/py: Add base test case for A/B updates

Add sandbox test for 'ab_select' command.

Test: ./test/py/test.py --bd sandbox --build -k test_ab

Signed-off-by: Ruslan Trofymenko <ruslan.trofymenko@linaro.org>
Signed-off-by: Igor Opaniuk <igor.opaniuk@gmail.com>
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Alistair Strachan <astrachan@google.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

configs/sandbox_defconfig

@@ -20,6 +20,7 @@ CONFIG_PRE_CON_BUF_ADDR=0xf0000
 CONFIG_LOG_MAX_LEVEL=6
 CONFIG_LOG_ERROR_RETURN=y
 CONFIG_DISPLAY_BOARDINFO_LATE=y
+CONFIG_ANDROID_AB=y
 CONFIG_CMD_CPU=y
 CONFIG_CMD_LICENSE=y
 CONFIG_CMD_BOOTZ=y
@@ -47,6 +48,7 @@ CONFIG_CMD_REMOTEPROC=y
 CONFIG_CMD_SPI=y
 CONFIG_CMD_USB=y
 CONFIG_CMD_AXI=y
+CONFIG_CMD_AB_SELECT=y
 CONFIG_CMD_TFTPPUT=y
 CONFIG_CMD_TFTPSRV=y
 CONFIG_CMD_RARP=y

test/py/tests/test_android/test_ab.py

@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: GPL-2.0
+# (C) Copyright 2018 Texas Instruments, <www.ti.com>
+
+# Test A/B update commands.
+
+import os
+import pytest
+import u_boot_utils
+
+class ABTestDiskImage(object):
+    """Disk Image used by the A/B tests."""
+
+    def __init__(self, u_boot_console):
+        """Initialize a new ABTestDiskImage object.
+
+        Args:
+            u_boot_console: A U-Boot console.
+
+        Returns:
+            Nothing.
+        """
+
+        filename = 'test_ab_disk_image.bin'
+
+        persistent = u_boot_console.config.persistent_data_dir + '/' + filename
+        self.path = u_boot_console.config.result_dir  + '/' + filename
+
+        with u_boot_utils.persistent_file_helper(u_boot_console.log, persistent):
+            if os.path.exists(persistent):
+                u_boot_console.log.action('Disk image file ' + persistent +
+                    ' already exists')
+            else:
+                u_boot_console.log.action('Generating ' + persistent)
+                fd = os.open(persistent, os.O_RDWR | os.O_CREAT)
+                os.ftruncate(fd, 524288)
+                os.close(fd)
+                cmd = ('sgdisk', persistent)
+                u_boot_utils.run_and_log(u_boot_console, cmd)
+
+                cmd = ('sgdisk', '--new=1:64:512', '--change-name=1:misc',
+                    persistent)
+                u_boot_utils.run_and_log(u_boot_console, cmd)
+                cmd = ('sgdisk', '--load-backup=' + persistent)
+                u_boot_utils.run_and_log(u_boot_console, cmd)
+
+        cmd = ('cp', persistent, self.path)
+        u_boot_utils.run_and_log(u_boot_console, cmd)
+
+di = None
+@pytest.fixture(scope='function')
+def ab_disk_image(u_boot_console):
+    global di
+    if not di:
+        di = ABTestDiskImage(u_boot_console)
+    return di
+
+@pytest.mark.boardspec('sandbox')
+@pytest.mark.buildconfigspec('android_ab')
+@pytest.mark.buildconfigspec('cmd_ab_select')
+@pytest.mark.requiredtool('sgdisk')
+def test_ab(ab_disk_image, u_boot_console):
+    """Test the 'ab_select' command."""
+
+    u_boot_console.run_command('host bind 0 ' + ab_disk_image.path)
+
+    output = u_boot_console.run_command('ab_select slot_name host 0#misc')
+    assert 're-initializing A/B metadata' in output
+    assert 'Attempting slot a, tries remaining 7' in output
+    output = u_boot_console.run_command('printenv slot_name')
+    assert 'slot_name=a' in output
+
+    output = u_boot_console.run_command('ab_select slot_name host 0:1')
+    assert 'Attempting slot b, tries remaining 7' in output
+    output = u_boot_console.run_command('printenv slot_name')
+    assert 'slot_name=b' in output