# Copyright (c) 2021 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import array
import fcntl
import os
import struct
import uuid

from autotest_lib.client.bin import test, utils
from autotest_lib.client.common_lib import error


class firmware_CheckEOPState(test.test):
    """Validates that the ME has been told by firmware that POST is done"""
    # Needed by autotest
    version = 1

    def read_post_boot_state(self):
        """Fail if the ME should be capable of reporting EOP but doesn't."""
        HECI_MKHI = uuid.UUID('{8e6a6715-9abc-4043-88ef-9e39c6f63e0f}')
        IOCTL_MEI_CONNECT_CLIENT = 0xc0104801  # _IOWR('H', 1, 16);

        try:
            mei_dev = os.open('/dev/mei0', os.O_RDWR)
        except OSError:
            raise error.TestFail('ME device not found, probably old kernel.')

        # Connect to MKHI
        buf = array.array('B', 16 * [0])
        struct.pack_into('<16s', buf, 0, HECI_MKHI.bytes_le)
        fcntl.ioctl(mei_dev, IOCTL_MEI_CONNECT_CLIENT, buf)
        max_msg_length, protocol_version = struct.unpack_from('<IB', buf)

        # Protocol 2 appears to be the minimum version that allows querying EOP
        if protocol_version < 2:
            os.close(mei_dev)
            raise error.TestNAError(
                    'ME protocol too old. Not checking for EOP.')

        # query EOP State
        group_id = 0xff
        command = 0x1d
        os.write(mei_dev, struct.pack('<BBBB', group_id, command, 0, 0))
        inb = os.read(mei_dev, max_msg_length)
        os.close(mei_dev)

        if len(inb) != 8:
            raise error.TestFail('Unknown response by ME.')

        group_id_resp, command_plus_80, rsvd, result, eop_state = struct.unpack(
                '<BBBBI', inb)

        if (group_id_resp != group_id) or (command_plus_80 != command | 0x80):
            raise error.TestFail('ME didn\'t respond to Query EOP State.')
        if result == 0x8d:
            raise error.TestFail('ME didn\'t understand Query EOP State.')
        if result == 0x8e:
            raise error.TestFail('ME reported failure on Query EOP State.')
        if result != 0:
            raise error.TestFail(
                    'ME gave unknown response to Query EOP State.')

        # if True, EOP has been issued by firmware and we're in Post-Boot State
        eop_state = (eop_state & 0xff) == 0

        return eop_state

    def run_once(self):
        """Fail unless ME returns Post-Boot State"""
        cpu_family = utils.get_cpu_soc_family()
        if cpu_family not in ('x86_64', 'i386'):
            raise error.TestNAError(
                    'This test is not applicable, '
                    'because a non-Intel device has been detected. '
                    'Such devices do not have an ME (Management Engine)')

        if utils.is_intel_uarch_older_than('Tiger Lake'):
            raise error.TestNAError('Skipping test on pre-TGL')
        if utils.is_intel_uarch_older_than('Gracemont'):
            raise error.TestNAError('Skipping test on production Atom designs')

        self.read_post_boot_state()