target-moxie/helper.c

   1 /*
   2  *  Moxie helper routines.
   3  *
   4  *  Copyright (c) 2008, 2009, 2010, 2013 Anthony Green
   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 General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <assert.h>
  23
  24 #include "config.h"
  25 #include "cpu.h"
  26 #include "mmu.h"
  27 #include "exec/exec-all.h"
  28 #include "qemu/host-utils.h"
  29 #include "helper.h"
  30
  31 #define MMUSUFFIX _mmu
  32
  33 #define SHIFT 0
  34 #include "exec/softmmu_template.h"
  35
  36 #define SHIFT 1
  37 #include "exec/softmmu_template.h"
  38
  39 #define SHIFT 2
  40 #include "exec/softmmu_template.h"
  41
  42 #define SHIFT 3
  43 #include "exec/softmmu_template.h"
  44
  45 /* Try to fill the TLB and return an exception if error. If retaddr is
  46    NULL, it means that the function was called in C code (i.e. not
  47    from generated code or from helper.c) */
  48 void tlb_fill(CPUMoxieState *env, target_ulong addr, int is_write, int mmu_idx,
  49               uintptr_t retaddr)
  50 {
  51     int ret;
  52
  53     ret = cpu_moxie_handle_mmu_fault(env, addr, is_write, mmu_idx);
  54     if (unlikely(ret)) {
  55         if (retaddr) {
  56             cpu_restore_state(env, retaddr);
  57         }
  58     }
  59     cpu_loop_exit(env);
  60 }
  61
  62 void helper_raise_exception(CPUMoxieState *env, int ex)
  63 {
  64     env->exception_index = ex;
  65     /* Stash the exception type.  */
  66     env->sregs[2] = ex;
  67     /* Stash the address where the exception occurred.  */
  68     cpu_restore_state(env, GETPC());
  69     env->sregs[5] = env->pc;
  70     /* Jump the the exception handline routine.  */
  71     env->pc = env->sregs[1];
  72     cpu_loop_exit(env);
  73 }
  74
  75 uint32_t helper_div(CPUMoxieState *env, uint32_t a, uint32_t b)
  76 {
  77     if (unlikely(b == 0)) {
  78         helper_raise_exception(env, MOXIE_EX_DIV0);
  79         return 0;
  80     }
  81     if (unlikely(a == INT_MIN && b == -1)) {
  82         return INT_MIN;
  83     }
  84
  85     return (int32_t)a / (int32_t)b;
  86 }
  87
  88 uint32_t helper_udiv(CPUMoxieState *env, uint32_t a, uint32_t b)
  89 {
  90     if (unlikely(b == 0)) {
  91         helper_raise_exception(env, MOXIE_EX_DIV0);
  92         return 0;
  93     }
  94     return a / b;
  95 }
  96
  97 void helper_debug(CPUMoxieState *env)
  98 {
  99     env->exception_index = EXCP_DEBUG;
 100     cpu_loop_exit(env);
 101 }
 102
 103 #if defined(CONFIG_USER_ONLY)
 104
 105 void moxie_cpu_do_interrupt(CPUState *env)
 106 {
 107     env->exception_index = -1;
 108 }
 109
 110 int cpu_moxie_handle_mmu_fault(CPUMoxieState *env, target_ulong address,
 111                                int rw, int mmu_idx)
 112 {
 113     env->exception_index = 0xaa;
 114     env->debug1 = address;
 115     cpu_dump_state(env, stderr, fprintf, 0);
 116     return 1;
 117 }
 118
 119 hwaddr cpu_get_phys_page_debug(CPUState *env, target_ulong addr)
 120 {
 121     return addr;
 122 }
 123
 124 #else /* !CONFIG_USER_ONLY */
 125
 126 int cpu_moxie_handle_mmu_fault(CPUMoxieState *env, target_ulong address,
 127                                int rw, int mmu_idx)
 128 {
 129     MoxieMMUResult res;
 130     int prot, miss;
 131     target_ulong phy;
 132     int r = 1;
 133
 134     address &= TARGET_PAGE_MASK;
 135     prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
 136     miss = moxie_mmu_translate(&res, env, address, rw, mmu_idx);
 137     if (miss) {
 138         /* handle the miss.  */
 139         phy = 0;
 140         env->exception_index = MOXIE_EX_MMU_MISS;
 141     } else {
 142         phy = res.phy;
 143         r = 0;
 144     }
 145     tlb_set_page(env, address, phy, prot, mmu_idx, TARGET_PAGE_SIZE);
 146     return r;
 147 }
 148
 149
 150 void moxie_cpu_do_interrupt(CPUState *cs)
 151 {
 152     MoxieCPU *cpu = MOXIE_CPU(cs);
 153     CPUMoxieState *env = &cpu->env;
 154
 155     switch (env->exception_index) {
 156     case MOXIE_EX_BREAK:
 157         break;
 158     default:
 159         break;
 160     }
 161 }
 162
 163 hwaddr cpu_get_phys_page_debug(CPUMoxieState *env, target_ulong addr)
 164 {
 165     uint32_t phy = addr;
 166     MoxieMMUResult res;
 167     int miss;
 168     miss = moxie_mmu_translate(&res, env, addr, 0, 0);
 169     if (!miss) {
 170         phy = res.phy;
 171     }
 172     return phy;
 173 }
 174 #endif