#!/usr/bin/env python3
# Copyright 2018 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.

"""Verify that RW can't update RO on locked fw"""

from __future__ import print_function

import sys
import time

import common
import hammerd_api # pylint: disable=import-error


# Before this test, please flash staff.bin using servo
# Negative test: Flash staff image from ToT (unlocked)


def main(argv):
  if argv:
    sys.exit('Test takes no args!')
  updater = hammerd_api.FirmwareUpdater(common.BASE_VENDOR_ID,
                                        common.BASE_PRODUCT_ID,
                                        common.BASE_USB_PATH)
  # Load EC image.
  with open(common.IMAGE, 'rb') as f:
    ec_image = f.read()
  updater.LoadEcImage(ec_image)

  common.disable_hammerd()
  common.connect_usb(updater)
  print('PDU Response: %s' % updater.GetFirstResponsePdu().contents)
  print('Current section before ro update: %s' % updater.CurrentSection())
  transfer_ro(updater, common.IMAGE)
  common.sim_disconnect_connect(updater)


def transfer_ro(updater, image):
  with open(image, 'rb') as f:
    ec_image = f.read()
  updater.LoadEcImage(ec_image)
  print('Transferring RO')
  transfer_result = updater.TransferImage(0)
  assert transfer_result == 0, 'RW should not be able to update locked RO!'
  updater.SendSubcommand(hammerd_api.UpdateExtraCommand.ImmediateReset)
  updater.CloseUsb()
  time.sleep(0.5)
  common.connect_usb(updater)
  print('PDU Response: %s' % updater.GetFirstResponsePdu().contents)
  print('Current running section: %s' % updater.CurrentSection())


def get_wp_status(updater):
  wp_rw = (get_flash_protection(updater) & common.EC_FLASH_PROTECT_RW_NOW) > 0
  return wp_rw


def unlock_rw(updater):
  # Check if RW is locked and unlock if needed
  wp_rw = get_wp_status(updater)
  print('WP status:  %s' %str(wp_rw))
  if wp_rw:
    print('Need to unlock RW')
    unlocked = updater.UnlockRW()
    assert unlocked == 1, 'Failed to unlock RW'
    common.reset_stay_ro(updater)


def get_flash_protection(updater):
  pdu_resp = updater.GetFirstResponsePdu().contents
  return pdu_resp.flash_protection

if __name__ == '__main__':
  sys.exit(main(sys.argv[1:]))