/*
    ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/**
 * @file ARMCM3/nvic.c
 * @brief Cortex-M3 NVIC support code.
 * @addtogroup ARMCM3_NVIC
 * @{
 */

#include <ch.h>
#include <nvic.h>

/**
 * @brief Sets the priority of an interrupt handler and enables it.
 *
 * @param n the interrupt number
 * @param prio the interrupt priority
 *
 * @note The parameters are not tested for correctness.
 */
void NVICEnableVector(uint32_t n, uint32_t prio) {
  unsigned sh = (n & 3) << 3;

  NVIC_IPR(n >> 2) = (NVIC_IPR(n >> 2) & ~(0xFF << sh)) | (prio << sh);
  NVIC_ISER(n >> 5) = 1 << (n & 0x1F);
}

/**
 * @brief Disables an interrupt handler.
 *
 * @param n the interrupt number
 *
 * @note The parameters are not tested for correctness.
 */
void NVICDisableVector(uint32_t n) {
  unsigned sh = (n & 3) << 3;

  NVIC_ICER(n >> 5) = 1 << (n & 0x1F);
  NVIC_IPR(n >> 2) = NVIC_IPR(n >> 2) & ~(0xFF << sh);
}

/**
 * @brief Changes the priority of a system handler.
 *
 * @param handler the system handler number
 * @param prio the system handler priority
 * @note The parameters are not tested for correctness.
 */
void NVICSetSystemHandlerPriority(uint32_t handler, uint32_t prio) {
  unsigned sh = (handler & 3) * 8;

  SCB_SHPR(handler >> 2) = (SCB_SHPR(handler >> 2) & ~(0xFF << sh)) | (prio << sh);
}

/** @} */