sh-intr.c

来自「this is ipl loader for hitachi SH4 proce」· C语言 代码 · 共 109 行

/* sh-intr.c: Interrupt functions for SH7750
 *
 *  Copyright (C) 2001 KOMORIYA Takeru
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 file "GPL" for more details.
 *
 * Contact to author:
 *   KOMORIYA Takeru, AAF Sendai Lab., Japan
 *   E-mail: [e-mail]
 *      URL: http://chmodx.dyndns.org/aaf/
 */

#include "sh7750.h"
#include "sh-intr.h"

/* Dummy function; do nothing */
void
intr_noop (void) {}

/* Interrupt jump table */
void * interrupt_table[60] = {
  0,         0,         0,         0,         0,
  0,         0,         0,         0,         0,
  0,         0,         0,         0,         0,
  0,         intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop, 
  intr_noop, intr_noop, intr_noop, intr_noop, intr_noop
};

/* Backup for interrupt jump table */
void * interrupt_table_bak[60] = {
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0,
  0, 0, 0, 0, 0
};

/* Register interrupt */
int
intr_register (int intr, void *function)
{
  if( interrupt_table_bak[intr] == 0 ){
    interrupt_table_bak[intr] = interrupt_table[intr];
    interrupt_table[intr] = function;
    return 0; /* Success */
  }
  return -1; /* Already registered */
}

/* Unregister interrupt */
int
intr_unregister (int intr)
{
  if( interrupt_table_bak[intr] != 0 ){
    interrupt_table[intr] = interrupt_table_bak[intr];
    interrupt_table_bak[intr] = 0;
    return 0; /* Success */
  }
  return -1; /* Not registered */
}

/* Set priority for peripheral modules
   pri: (High) 15 <---> 1 (Low), 0 : Masked  */
void
intr_set_priority (int intr, int pri)
{
  unsigned int ipr, mask, shift;

  ipr = intr >> 4;
  shift = intr & 0x0f;
  mask = 0xf << shift;

  switch (ipr)
    {
    case 0:
      IPRA = (IPRA & ~mask) | (pri << shift);
      break;
    case 1:
      IPRB = (IPRB & ~mask) | (pri << shift);
      break;
    case 2:
      IPRC = (IPRC & ~mask) | (pri << shift);
      break;
    }
}