/* SPDX-License-Identifier: BSD-2-Clause */

/**
 * @file
 *
 * @ingroup RTEMSScoreCPUARM
 *
 * @brief This source file contains the ARM-specific _CPU_ISR_install_vector().
 */

/*
 *  COPYRIGHT (c) 2000 Canon Research Centre France SA.
 *  Emmanuel Raguet, mailto:raguet@crf.canon.fr
 *
 *  Copyright (c) 2002 Advent Networks, Inc
 *      Jay Monkman <jmonkman@adventnetworks.com>
 *
 *  Copyright (C) 2009, 2017 embedded brains GmbH & Co. KG
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <rtems/score/cpu.h>

#ifdef ARM_MULTILIB_ARCH_V4

void _CPU_ISR_install_vector(
  uint32_t         vector,
  CPU_ISR_handler  new_handler,
  CPU_ISR_handler *old_handler
)
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Warray-bounds"
  /* Redirection table starts at the end of the vector table */
  CPU_ISR_handler volatile  *table = (CPU_ISR_handler *) (MAX_EXCEPTIONS * 4);

  CPU_ISR_handler current_handler = table [vector];

  /* The current handler is now the old one */
  if (old_handler != NULL) {
    *old_handler = current_handler;
  }

  /* Write only if necessary to avoid writes to a maybe read-only memory */
  if (current_handler != new_handler) {
    table [vector] = new_handler;
  }
#pragma GCC diagnostic pop
}

#endif /* ARM_MULTILIB_ARCH_V4 */