LXR qemu/target/openrisc/interrupt.c

   1/*
   2 * OpenRISC interrupt.
   3 *
   4 * Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com>
   5 *
   6 * This library is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU Lesser General Public
   8 * License as published by the Free Software Foundation; either
   9 * version 2.1 of the License, or (at your option) any later version.
  10 *
  11 * This library is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 * Lesser General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU Lesser General Public
  17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20#include "qemu/osdep.h"
  21#include "cpu.h"
  22#include "exec/exec-all.h"
  23#include "exec/gdbstub.h"
  24#include "qemu/host-utils.h"
  25#ifndef CONFIG_USER_ONLY
  26#include "hw/loader.h"
  27#endif
  28
  29void openrisc_cpu_do_interrupt(CPUState *cs)
  30{
  31    OpenRISCCPU *cpu = OPENRISC_CPU(cs);
  32    CPUOpenRISCState *env = &cpu->env;
  33    int exception = cs->exception_index;
  34
  35    env->epcr = env->pc;
  36    if (exception == EXCP_SYSCALL) {
  37        env->epcr += 4;
  38    }
  39    /* When we have an illegal instruction the error effective address
  40       shall be set to the illegal instruction address.  */
  41    if (exception == EXCP_ILLEGAL) {
  42        env->eear = env->pc;
  43    }
  44
  45    /* During exceptions esr is populared with the pre-exception sr.  */
  46    env->esr = cpu_get_sr(env);
  47    /* In parallel sr is updated to disable mmu, interrupts, timers and
  48       set the delay slot exception flag.  */
  49    env->sr &= ~SR_DME;
  50    env->sr &= ~SR_IME;
  51    env->sr |= SR_SM;
  52    env->sr &= ~SR_IEE;
  53    env->sr &= ~SR_TEE;
  54    env->pmr &= ~PMR_DME;
  55    env->pmr &= ~PMR_SME;
  56    env->lock_addr = -1;
  57
  58    /* Set/clear dsx to indicate if we are in a delay slot exception.  */
  59    if (env->dflag) {
  60        env->dflag = 0;
  61        env->sr |= SR_DSX;
  62        env->epcr -= 4;
  63    } else {
  64        env->sr &= ~SR_DSX;
  65    }
  66
  67    if (exception > 0 && exception < EXCP_NR) {
  68        static const char * const int_name[EXCP_NR] = {
  69            [EXCP_RESET]    = "RESET",
  70            [EXCP_BUSERR]   = "BUSERR (bus error)",
  71            [EXCP_DPF]      = "DFP (data protection fault)",
  72            [EXCP_IPF]      = "IPF (code protection fault)",
  73            [EXCP_TICK]     = "TICK (timer interrupt)",
  74            [EXCP_ALIGN]    = "ALIGN",
  75            [EXCP_ILLEGAL]  = "ILLEGAL",
  76            [EXCP_INT]      = "INT (device interrupt)",
  77            [EXCP_DTLBMISS] = "DTLBMISS (data tlb miss)",
  78            [EXCP_ITLBMISS] = "ITLBMISS (code tlb miss)",
  79            [EXCP_RANGE]    = "RANGE",
  80            [EXCP_SYSCALL]  = "SYSCALL",
  81            [EXCP_FPE]      = "FPE",
  82            [EXCP_TRAP]     = "TRAP",
  83        };
  84
  85        qemu_log_mask(CPU_LOG_INT, "INT: %s\n", int_name[exception]);
  86
  87        hwaddr vect_pc = exception << 8;
  88        if (env->cpucfgr & CPUCFGR_EVBARP) {
  89            vect_pc |= env->evbar;
  90        }
  91        if (env->sr & SR_EPH) {
  92            vect_pc |= 0xf0000000;
  93        }
  94        env->pc = vect_pc;
  95    } else {
  96        cpu_abort(cs, "Unhandled exception 0x%x\n", exception);
  97    }
  98
  99    cs->exception_index = -1;
 100}
 101
 102bool openrisc_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
 103{
 104    OpenRISCCPU *cpu = OPENRISC_CPU(cs);
 105    CPUOpenRISCState *env = &cpu->env;
 106    int idx = -1;
 107
 108    if ((interrupt_request & CPU_INTERRUPT_HARD) && (env->sr & SR_IEE)) {
 109        idx = EXCP_INT;
 110    }
 111    if ((interrupt_request & CPU_INTERRUPT_TIMER) && (env->sr & SR_TEE)) {
 112        idx = EXCP_TICK;
 113    }
 114    if (idx >= 0) {
 115        cs->exception_index = idx;
 116        openrisc_cpu_do_interrupt(cs);
 117        return true;
 118    }
 119    return false;
 120}
 121