kernel/arch/arm32/src/interrupt.c

   1 /*
   2  * Copyright (c) 2007 Petr Stepan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup kernel_arm32
  30  * @{
  31  */
  32 /** @file
  33  *  @brief Interrupts controlling routines.
  34  */
  35
  36 #include <arch/asm.h>
  37 #include <arch/regutils.h>
  38 #include <arch/machine_func.h>
  39 #include <ddi/irq.h>
  40 #include <interrupt.h>
  41
  42 /** Disable interrupts.
  43  *
  44  * @return Old interrupt priority level.
  45  */
  46 ipl_t interrupts_disable(void)
  47 {
  48         ipl_t ipl = current_status_reg_read();
  49
  50         current_status_reg_control_write(STATUS_REG_IRQ_DISABLED_BIT | ipl);
  51
  52         return ipl;
  53 }
  54
  55 /** Enable interrupts.
  56  *
  57  * @return Old interrupt priority level.
  58  */
  59 ipl_t interrupts_enable(void)
  60 {
  61         ipl_t ipl = current_status_reg_read();
  62
  63         current_status_reg_control_write(ipl & ~STATUS_REG_IRQ_DISABLED_BIT);
  64
  65         return ipl;
  66 }
  67
  68 /** Restore interrupt priority level.
  69  *
  70  * @param ipl Saved interrupt priority level.
  71  */
  72 void interrupts_restore(ipl_t ipl)
  73 {
  74         current_status_reg_control_write(
  75             (current_status_reg_read() & ~STATUS_REG_IRQ_DISABLED_BIT) |
  76             (ipl & STATUS_REG_IRQ_DISABLED_BIT));
  77 }
  78
  79 /** Read interrupt priority level.
  80  *
  81  * @return Current interrupt priority level.
  82  */
  83 ipl_t interrupts_read(void)
  84 {
  85         return current_status_reg_read();
  86 }
  87
  88 /** Check interrupts state.
  89  *
  90  * @return True if interrupts are disabled.
  91  *
  92  */
  93 bool interrupts_disabled(void)
  94 {
  95         return current_status_reg_read() & STATUS_REG_IRQ_DISABLED_BIT;
  96 }
  97
  98 /** Initialize basic tables for exception dispatching
  99  * and starts the timer.
 100  */
 101 void interrupt_init(void)
 102 {
 103         size_t irq_count;
 104
 105         irq_count = machine_get_irq_count();
 106         irq_init(irq_count, irq_count);
 107
 108         machine_timer_irq_start();
 109 }
 110
 111 /** @}
 112  */