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 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 "cpu.h"
  21 #include "qemu-common.h"
  22 #include "exec/gdbstub.h"
  23 #include "qemu/host-utils.h"
  24 #ifndef CONFIG_USER_ONLY
  25 #include "hw/loader.h"
  26 #endif
  27
  28 void openrisc_cpu_do_interrupt(CPUState *cs)
  29 {
  30     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
  31     CPUOpenRISCState *env = &cpu->env;
  32 #ifndef CONFIG_USER_ONLY
  33     if (env->flags & D_FLAG) { /* Delay Slot insn */
  34         env->flags &= ~D_FLAG;
  35         env->sr |= SR_DSX;
  36         if (env->exception_index == EXCP_TICK    ||
  37             env->exception_index == EXCP_INT     ||
  38             env->exception_index == EXCP_SYSCALL ||
  39             env->exception_index == EXCP_FPE) {
  40             env->epcr = env->jmp_pc;
  41         } else {
  42             env->epcr = env->pc - 4;
  43         }
  44     } else {
  45         if (env->exception_index == EXCP_TICK    ||
  46             env->exception_index == EXCP_INT     ||
  47             env->exception_index == EXCP_SYSCALL ||
  48             env->exception_index == EXCP_FPE) {
  49             env->epcr = env->npc;
  50         } else {
  51             env->epcr = env->pc;
  52         }
  53     }
  54
  55     /* For machine-state changed between user-mode and supervisor mode,
  56        we need flush TLB when we enter&exit EXCP.  */
  57     tlb_flush(env, 1);
  58
  59     env->esr = env->sr;
  60     env->sr &= ~SR_DME;
  61     env->sr &= ~SR_IME;
  62     env->sr |= SR_SM;
  63     env->sr &= ~SR_IEE;
  64     env->sr &= ~SR_TEE;
  65     env->tlb->cpu_openrisc_map_address_data = &cpu_openrisc_get_phys_nommu;
  66     env->tlb->cpu_openrisc_map_address_code = &cpu_openrisc_get_phys_nommu;
  67
  68     if (env->exception_index > 0 && env->exception_index < EXCP_NR) {
  69         env->pc = (env->exception_index << 8);
  70     } else {
  71         cpu_abort(env, "Unhandled exception 0x%x\n", env->exception_index);
  72     }
  73 #endif
  74
  75     env->exception_index = -1;
  76 }