test/py: saveenv: Add a test for saveenv command

Add test case for saveenv command in non-JTAG bootmode which saves the
u-boot environment variables in persistent storage.

Signed-off-by: Love Kumar <love.kumar@amd.com>

test/py/tests/test_saveenv.py

@@ -0,0 +1,137 @@
+# SPDX-License-Identifier: GPL-2.0
+# (C) Copyright 2023, Advanced Micro Devices, Inc.
+
+"""
+Note: This test doesn't rely on boardenv_* configuration value but they can
+change test behavior.
+
+For example:
+
+# Setup env__saveenv_test_skip to True if saveenv test is not possible or
+# desired and should be skipped.
+env__saveenv_test_skip = True
+
+# Setup env__saveenv_test to set the bootmode if 'modeboot' u-boot environment
+# variable is not set. Test will be skipped if bootmode is not set in both
+# places i.e, boardenv and modeboot u-boot environment variable
+env__saveenv_test = {
+    'bootmode': 'qspiboot',
+}
+
+# This test will be also skipped if the bootmode is detected to JTAG.
+"""
+
+import pytest
+import random
+import ipaddress
+import string
+import uuid
+
+# Setup the env
+def setup_saveenv_env(u_boot_console):
+    if u_boot_console.config.env.get('env__saveenv_test_skip', False):
+        pytest.skip('saveenv test is not enabled')
+
+    output = u_boot_console.run_command('echo $modeboot')
+    if output:
+        bootmode = output
+    else:
+        f = u_boot_console.config.env.get('env__saveenv_test', None)
+        if not f:
+            pytest.skip('bootmode cannot be determined')
+        bootmode = f.get('bootmode', 'jtagboot')
+
+    if 'jtag' in bootmode:
+        pytest.skip('skipping saveenv test due to jtag bootmode')
+
+# Check return code
+def ret_code(u_boot_console):
+    return u_boot_console.run_command('echo $?')
+
+# Verify env variable
+def check_env(u_boot_console, var_name, var_value):
+    if var_value:
+        output = u_boot_console.run_command(f'printenv {var_name}')
+        var_value = str(var_value)
+        if (var_value.startswith("'") and var_value.endswith("'")) or (
+            var_value.startswith('"') and var_value.endswith('"')
+        ):
+            var_value = var_value.split(var_value[-1])[1]
+        assert var_value in output
+        assert ret_code(u_boot_console).endswith('0')
+    else:
+        u_boot_console.p.send(f'printenv {var_name}\n')
+        output = u_boot_console.p.expect(['not defined'])
+        assert output == 0
+        assert ret_code(u_boot_console).endswith('1')
+
+# Set env variable
+def set_env(u_boot_console, var_name, var_value):
+    u_boot_console.run_command(f'setenv {var_name} {var_value}')
+    assert ret_code(u_boot_console).endswith('0')
+    check_env(u_boot_console, var_name, var_value)
+
+@pytest.mark.buildconfigspec('cmd_saveenv')
+@pytest.mark.buildconfigspec('hush_parser')
+def test_saveenv(u_boot_console):
+    """Test the saveenv command in non-JTAG bootmode.
+    It saves the U-Boot environment in persistent storage.
+    """
+    setup_saveenv_env(u_boot_console)
+
+    # Set env for random mac address
+    rand_mac = '%02x:%02x:%02x:%02x:%02x:%02x' % (
+        random.randint(0, 255),
+        random.randint(0, 255),
+        random.randint(0, 255),
+        random.randint(0, 255),
+        random.randint(0, 255),
+        random.randint(0, 255),
+    )
+    set_env(u_boot_console, 'mac_addr', rand_mac)
+
+    # Set env for random IPv4 address
+    rand_ipv4 = ipaddress.IPv4Address._string_from_ip_int(
+        random.randint(0, ipaddress.IPv4Address._ALL_ONES)
+    )
+    set_env(u_boot_console, 'ipv4_addr', rand_ipv4)
+
+    # Set env for random IPv6 address
+    rand_ipv6 = ipaddress.IPv6Address._string_from_ip_int(
+        random.randint(0, ipaddress.IPv6Address._ALL_ONES)
+    )
+    set_env(u_boot_console, 'ipv6_addr', rand_ipv6)
+
+    # Set env for random number
+    rand_num = random.randrange(1, 10**9)
+    set_env(u_boot_console, 'num_var', rand_num)
+
+    # Set env for uuid
+    uuid_str = uuid.uuid4().hex.lower()
+    set_env(u_boot_console, 'uuid_var', uuid_str)
+
+    # Set env for random string including special characters
+    sc = "!#%&()*+,-./:;<=>?@[\\]^_`{|}~"
+    rand_str = ''.join(
+        random.choices(' ' + string.ascii_letters + sc + string.digits, k=300)
+    )
+    set_env(u_boot_console, 'str_var', f'"{rand_str}"')
+
+    # Set env for empty string
+    set_env(u_boot_console, 'empty_var', '')
+
+    # Save the env variables
+    u_boot_console.run_command('saveenv')
+    assert ret_code(u_boot_console).endswith('0')
+
+    # Reboot
+    u_boot_console.run_command('reset', wait_for_reboot=True)
+
+    # Verify the saved env variables
+    check_env(u_boot_console, 'mac_addr', rand_mac)
+    check_env(u_boot_console, 'ipv4_addr', rand_ipv4)
+    check_env(u_boot_console, 'ipv6_addr', rand_ipv6)
+    check_env(u_boot_console, 'num_var', rand_num)
+    check_env(u_boot_console, 'uuid_var', uuid_str)
+    check_env(u_boot_console, 'str_var', rand_str)
+    check_env(u_boot_console, 'empty_var', '')