Logo Search packages:      
Sourcecode: linux version File versions  Download package

sim_int.c

/*
 * Copyright (C) 1999, 2005 MIPS Technologies, Inc.  All rights reserved.
 *
 *  This program is free software; you can distribute it and/or modify it
 *  under the terms of the GNU General Public License (Version 2) as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope 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, write to the Free Software Foundation, Inc.,
 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 */
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <asm/mips-boards/simint.h>
#include <asm/irq_cpu.h>

static inline int clz(unsigned long x)
{
      __asm__(
      "     .set  push                          \n"
      "     .set  mips32                              \n"
      "     clz   %0, %1                              \n"
      "     .set  pop                           \n"
      : "=r" (x)
      : "r" (x));

      return x;
}

/*
 * Version of ffs that only looks at bits 12..15.
 */
static inline unsigned int irq_ffs(unsigned int pending)
{
#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
      return -clz(pending) + 31 - CAUSEB_IP;
#else
      unsigned int a0 = 7;
      unsigned int t0;

      t0 = s0 & 0xf000;
      t0 = t0 < 1;
      t0 = t0 << 2;
      a0 = a0 - t0;
      s0 = s0 << t0;

      t0 = s0 & 0xc000;
      t0 = t0 < 1;
      t0 = t0 << 1;
      a0 = a0 - t0;
      s0 = s0 << t0;

      t0 = s0 & 0x8000;
      t0 = t0 < 1;
      /* t0 = t0 << 2; */
      a0 = a0 - t0;
      /* s0 = s0 << t0; */

      return a0;
#endif
}

asmlinkage void plat_irq_dispatch(void)
{
      unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
      int irq;

      irq = irq_ffs(pending);

      if (irq > 0)
            do_IRQ(MIPS_CPU_IRQ_BASE + irq);
      else
            spurious_interrupt();
}

void __init arch_init_irq(void)
{
      mips_cpu_irq_init();
}

Generated by  Doxygen 1.6.0   Back to index