shared/cp15/arm-cp15-set-exception-handler.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSBSPsARMShared
0007  *
0008  * @brief This source file contains the implementation of
0009  *   arm_cp15_set_exception_handler().
0010  */
0011
0012 /*
0013  * Copyright (c) 2013 embedded brains GmbH & Co. KG
0014  *
0015  * Redistribution and use in source and binary forms, with or without
0016  * modification, are permitted provided that the following conditions
0017  * are met:
0018  * 1. Redistributions of source code must retain the above copyright
0019  *    notice, this list of conditions and the following disclaimer.
0020  * 2. Redistributions in binary form must reproduce the above copyright
0021  *    notice, this list of conditions and the following disclaimer in the
0022  *    documentation and/or other materials provided with the distribution.
0023  *
0024  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0025  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0026  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0027  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0028  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0029  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0030  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0031  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0032  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0033  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0034  * POSSIBILITY OF SUCH DAMAGE.
0035  */
0036
0037 #include <libcpu/arm-cp15.h>
0038
0039 #include <bsp/linker-symbols.h>
0040
0041 void* arm_cp15_set_exception_handler(
0042   Arm_symbolic_exception_name exception,
0043   void (*handler)(void)
0044 )
0045 {
0046   uint32_t current_handler = 0;
0047
0048   if ((unsigned) exception < MAX_EXCEPTIONS) {
0049     uint32_t *cpu_table = (uint32_t *) 0 + MAX_EXCEPTIONS;
0050     uint32_t *mirror_table = (uint32_t *) bsp_vector_table_begin + MAX_EXCEPTIONS;
0051
0052     current_handler = mirror_table[exception];
0053
0054     if (current_handler != (uint32_t) handler) {
0055       size_t table_size = MAX_EXCEPTIONS * sizeof(uint32_t);
0056       uint32_t cls = arm_cp15_get_min_cache_line_size();
0057       uint32_t ctrl;
0058       rtems_interrupt_level level;
0059
0060       rtems_interrupt_local_disable(level);
0061
0062       ctrl = arm_cp15_mmu_disable(cls);
0063
0064       mirror_table[exception] = (uint32_t) handler;
0065
0066       rtems_cache_flush_multiple_data_lines(mirror_table, table_size);
0067
0068       /*
0069        * On ARMv7 processors with the Security Extension the mirror table might
0070        * be the actual table used by the processor.
0071        */
0072       rtems_cache_invalidate_multiple_instruction_lines(mirror_table, table_size);
0073
0074       rtems_cache_invalidate_multiple_instruction_lines(cpu_table, table_size);
0075
0076       arm_cp15_set_control(ctrl);
0077
0078       rtems_interrupt_local_enable(level);
0079     }
0080   }
0081
0082   return (void*) current_handler;
0083 }