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Diffstat (limited to 'roms/u-boot/test/py/u_boot_utils.py')
| -rw-r--r-- | roms/u-boot/test/py/u_boot_utils.py | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/roms/u-boot/test/py/u_boot_utils.py b/roms/u-boot/test/py/u_boot_utils.py new file mode 100644 index 000000000..939d82eec --- /dev/null +++ b/roms/u-boot/test/py/u_boot_utils.py @@ -0,0 +1,341 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. + +# Utility code shared across multiple tests. + +import hashlib +import inspect +import os +import os.path +import pytest +import sys +import time +import re + +def md5sum_data(data): + """Calculate the MD5 hash of some data. + + Args: + data: The data to hash. + + Returns: + The hash of the data, as a binary string. + """ + + h = hashlib.md5() + h.update(data) + return h.digest() + +def md5sum_file(fn, max_length=None): + """Calculate the MD5 hash of the contents of a file. + + Args: + fn: The filename of the file to hash. + max_length: The number of bytes to hash. If the file has more + bytes than this, they will be ignored. If None or omitted, the + entire file will be hashed. + + Returns: + The hash of the file content, as a binary string. + """ + + with open(fn, 'rb') as fh: + if max_length: + params = [max_length] + else: + params = [] + data = fh.read(*params) + return md5sum_data(data) + +class PersistentRandomFile(object): + """Generate and store information about a persistent file containing + random data.""" + + def __init__(self, u_boot_console, fn, size): + """Create or process the persistent file. + + If the file does not exist, it is generated. + + If the file does exist, its content is hashed for later comparison. + + These files are always located in the "persistent data directory" of + the current test run. + + Args: + u_boot_console: A console connection to U-Boot. + fn: The filename (without path) to create. + size: The desired size of the file in bytes. + + Returns: + Nothing. + """ + + self.fn = fn + + self.abs_fn = u_boot_console.config.persistent_data_dir + '/' + fn + + if os.path.exists(self.abs_fn): + u_boot_console.log.action('Persistent data file ' + self.abs_fn + + ' already exists') + self.content_hash = md5sum_file(self.abs_fn) + else: + u_boot_console.log.action('Generating ' + self.abs_fn + + ' (random, persistent, %d bytes)' % size) + data = os.urandom(size) + with open(self.abs_fn, 'wb') as fh: + fh.write(data) + self.content_hash = md5sum_data(data) + +def attempt_to_open_file(fn): + """Attempt to open a file, without throwing exceptions. + + Any errors (exceptions) that occur during the attempt to open the file + are ignored. This is useful in order to test whether a file (in + particular, a device node) exists and can be successfully opened, in order + to poll for e.g. USB enumeration completion. + + Args: + fn: The filename to attempt to open. + + Returns: + An open file handle to the file, or None if the file could not be + opened. + """ + + try: + return open(fn, 'rb') + except: + return None + +def wait_until_open_succeeds(fn): + """Poll until a file can be opened, or a timeout occurs. + + Continually attempt to open a file, and return when this succeeds, or + raise an exception after a timeout. + + Args: + fn: The filename to attempt to open. + + Returns: + An open file handle to the file. + """ + + for i in range(100): + fh = attempt_to_open_file(fn) + if fh: + return fh + time.sleep(0.1) + raise Exception('File could not be opened') + +def wait_until_file_open_fails(fn, ignore_errors): + """Poll until a file cannot be opened, or a timeout occurs. + + Continually attempt to open a file, and return when this fails, or + raise an exception after a timeout. + + Args: + fn: The filename to attempt to open. + ignore_errors: Indicate whether to ignore timeout errors. If True, the + function will simply return if a timeout occurs, otherwise an + exception will be raised. + + Returns: + Nothing. + """ + + for i in range(100): + fh = attempt_to_open_file(fn) + if not fh: + return + fh.close() + time.sleep(0.1) + if ignore_errors: + return + raise Exception('File can still be opened') + +def run_and_log(u_boot_console, cmd, ignore_errors=False): + """Run a command and log its output. + + Args: + u_boot_console: A console connection to U-Boot. + cmd: The command to run, as an array of argv[], or a string. + If a string, note that it is split up so that quoted spaces + will not be preserved. E.g. "fred and" becomes ['"fred', 'and"'] + ignore_errors: Indicate whether to ignore errors. If True, the function + will simply return if the command cannot be executed or exits with + an error code, otherwise an exception will be raised if such + problems occur. + + Returns: + The output as a string. + """ + if isinstance(cmd, str): + cmd = cmd.split() + runner = u_boot_console.log.get_runner(cmd[0], sys.stdout) + output = runner.run(cmd, ignore_errors=ignore_errors) + runner.close() + return output + +def run_and_log_expect_exception(u_boot_console, cmd, retcode, msg): + """Run a command that is expected to fail. + + This runs a command and checks that it fails with the expected return code + and exception method. If not, an exception is raised. + + Args: + u_boot_console: A console connection to U-Boot. + cmd: The command to run, as an array of argv[]. + retcode: Expected non-zero return code from the command. + msg: String that should be contained within the command's output. + """ + try: + runner = u_boot_console.log.get_runner(cmd[0], sys.stdout) + runner.run(cmd) + except Exception as e: + assert(retcode == runner.exit_status) + assert(msg in runner.output) + else: + raise Exception("Expected an exception with retcode %d message '%s'," + "but it was not raised" % (retcode, msg)) + finally: + runner.close() + +ram_base = None +def find_ram_base(u_boot_console): + """Find the running U-Boot's RAM location. + + Probe the running U-Boot to determine the address of the first bank + of RAM. This is useful for tests that test reading/writing RAM, or + load/save files that aren't associated with some standard address + typically represented in an environment variable such as + ${kernel_addr_r}. The value is cached so that it only needs to be + actively read once. + + Args: + u_boot_console: A console connection to U-Boot. + + Returns: + The address of U-Boot's first RAM bank, as an integer. + """ + + global ram_base + if u_boot_console.config.buildconfig.get('config_cmd_bdi', 'n') != 'y': + pytest.skip('bdinfo command not supported') + if ram_base == -1: + pytest.skip('Previously failed to find RAM bank start') + if ram_base is not None: + return ram_base + + with u_boot_console.log.section('find_ram_base'): + response = u_boot_console.run_command('bdinfo') + for l in response.split('\n'): + if '-> start' in l or 'memstart =' in l: + ram_base = int(l.split('=')[1].strip(), 16) + break + if ram_base is None: + ram_base = -1 + raise Exception('Failed to find RAM bank start in `bdinfo`') + + # We don't want ram_base to be zero as some functions test if the given + # address is NULL (0). Besides, on some RISC-V targets the low memory + # is protected that prevents S-mode U-Boot from access. + # Let's add 2MiB then (size of an ARM LPAE/v8 section). + + ram_base += 1024 * 1024 * 2 + + return ram_base + +class PersistentFileHelperCtxMgr(object): + """A context manager for Python's "with" statement, which ensures that any + generated file is deleted (and hence regenerated) if its mtime is older + than the mtime of the Python module which generated it, and gets an mtime + newer than the mtime of the Python module which generated after it is + generated. Objects of this type should be created by factory function + persistent_file_helper rather than directly.""" + + def __init__(self, log, filename): + """Initialize a new object. + + Args: + log: The Logfile object to log to. + filename: The filename of the generated file. + + Returns: + Nothing. + """ + + self.log = log + self.filename = filename + + def __enter__(self): + frame = inspect.stack()[1] + module = inspect.getmodule(frame[0]) + self.module_filename = module.__file__ + self.module_timestamp = os.path.getmtime(self.module_filename) + + if os.path.exists(self.filename): + filename_timestamp = os.path.getmtime(self.filename) + if filename_timestamp < self.module_timestamp: + self.log.action('Removing stale generated file ' + + self.filename) + os.unlink(self.filename) + + def __exit__(self, extype, value, traceback): + if extype: + try: + os.path.unlink(self.filename) + except: + pass + return + logged = False + for i in range(20): + filename_timestamp = os.path.getmtime(self.filename) + if filename_timestamp > self.module_timestamp: + break + if not logged: + self.log.action( + 'Waiting for generated file timestamp to increase') + logged = True + os.utime(self.filename) + time.sleep(0.1) + +def persistent_file_helper(u_boot_log, filename): + """Manage the timestamps and regeneration of a persistent generated + file. This function creates a context manager for Python's "with" + statement + + Usage: + with persistent_file_helper(u_boot_console.log, filename): + code to generate the file, if it's missing. + + Args: + u_boot_log: u_boot_console.log. + filename: The filename of the generated file. + + Returns: + A context manager object. + """ + + return PersistentFileHelperCtxMgr(u_boot_log, filename) + +def crc32(u_boot_console, address, count): + """Helper function used to compute the CRC32 value of a section of RAM. + + Args: + u_boot_console: A U-Boot console connection. + address: Address where data starts. + count: Amount of data to use for calculation. + + Returns: + CRC32 value + """ + + bcfg = u_boot_console.config.buildconfig + has_cmd_crc32 = bcfg.get('config_cmd_crc32', 'n') == 'y' + assert has_cmd_crc32, 'Cannot compute crc32 without CONFIG_CMD_CRC32.' + output = u_boot_console.run_command('crc32 %08x %x' % (address, count)) + + m = re.search('==> ([0-9a-fA-F]{8})$', output) + assert m, 'CRC32 operation failed.' + + return m.group(1) |