text: /*
   * Copyright (c) 2015 Wind River Systems, Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  /**
   * @file
   * @brief Initialize system clock driver
   *
   * Initializing the timer driver is done in this module to reduce code
   * duplication.  Although both nanokernel and microkernel systems initialize
   * the timer driver at the same point, the two systems differ in when the system
   * can begin to process system clock ticks.  A nanokernel system can process
   * system clock ticks once the driver has initialized.  However, in a
   * microkernel system all system clock ticks are deferred (and stored on the
   * kernel server command stack) until the kernel server fiber starts and begins
   * processing any queued ticks.
   */
  
  #include <nanokernel.h>
  #include <init.h>
  #include <drivers/system_timer.h>
  
  /*
   * Currently only loapic timer implements device pm ops.
   * For other timers, define device_pm_ops with default handers in case
   * the app enables CONFIG_DEVICE_POWER_MANAGEMENT.
   */
  #ifndef CONFIG_LOAPIC_TIMER
  DEFINE_DEVICE_PM_OPS(_sys_clock, device_pm_nop, device_pm_nop);
  #endif
  SYS_INIT_PM("sys_clock", _sys_clock_driver_init, DEVICE_PM_OPS_GET(_sys_clock),
  	    SECONDARY, CONFIG_SYSTEM_CLOCK_INIT_PRIORITY);
  