target/nios2/cpu.c

   1 /*
   2  * QEMU Nios II CPU
   3  *
   4  * Copyright (c) 2012 Chris Wulff <crwulff@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
  18  * <http://www.gnu.org/licenses/lgpl-2.1.html>
  19  */
  20
  21 #include "qemu/osdep.h"
  22 #include "qemu/module.h"
  23 #include "qapi/error.h"
  24 #include "cpu.h"
  25 #include "exec/log.h"
  26 #include "exec/gdbstub.h"
  27 #include "hw/qdev-properties.h"
  28
  29 static void nios2_cpu_set_pc(CPUState *cs, vaddr value)
  30 {
  31     Nios2CPU *cpu = NIOS2_CPU(cs);
  32     CPUNios2State *env = &cpu->env;
  33
  34     env->regs[R_PC] = value;
  35 }
  36
  37 static bool nios2_cpu_has_work(CPUState *cs)
  38 {
  39     return cs->interrupt_request & (CPU_INTERRUPT_HARD | CPU_INTERRUPT_NMI);
  40 }
  41
  42 /* CPUClass::reset() */
  43 static void nios2_cpu_reset(CPUState *cs)
  44 {
  45     Nios2CPU *cpu = NIOS2_CPU(cs);
  46     Nios2CPUClass *ncc = NIOS2_CPU_GET_CLASS(cpu);
  47     CPUNios2State *env = &cpu->env;
  48
  49     if (qemu_loglevel_mask(CPU_LOG_RESET)) {
  50         qemu_log("CPU Reset (CPU %d)\n", cs->cpu_index);
  51         log_cpu_state(cs, 0);
  52     }
  53
  54     ncc->parent_reset(cs);
  55
  56     memset(env->regs, 0, sizeof(uint32_t) * NUM_CORE_REGS);
  57     env->regs[R_PC] = cpu->reset_addr;
  58
  59 #if defined(CONFIG_USER_ONLY)
  60     /* Start in user mode with interrupts enabled. */
  61     env->regs[CR_STATUS] = CR_STATUS_U | CR_STATUS_PIE;
  62 #else
  63     env->regs[CR_STATUS] = 0;
  64 #endif
  65 }
  66
  67 static void nios2_cpu_initfn(Object *obj)
  68 {
  69     Nios2CPU *cpu = NIOS2_CPU(obj);
  70
  71     cpu_set_cpustate_pointers(cpu);
  72
  73 #if !defined(CONFIG_USER_ONLY)
  74     mmu_init(&cpu->env);
  75 #endif
  76 }
  77
  78 static ObjectClass *nios2_cpu_class_by_name(const char *cpu_model)
  79 {
  80     return object_class_by_name(TYPE_NIOS2_CPU);
  81 }
  82
  83 static void nios2_cpu_realizefn(DeviceState *dev, Error **errp)
  84 {
  85     CPUState *cs = CPU(dev);
  86     Nios2CPUClass *ncc = NIOS2_CPU_GET_CLASS(dev);
  87     Error *local_err = NULL;
  88
  89     cpu_exec_realizefn(cs, &local_err);
  90     if (local_err != NULL) {
  91         error_propagate(errp, local_err);
  92         return;
  93     }
  94
  95     qemu_init_vcpu(cs);
  96     cpu_reset(cs);
  97
  98     ncc->parent_realize(dev, errp);
  99 }
 100
 101 static bool nios2_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
 102 {
 103     Nios2CPU *cpu = NIOS2_CPU(cs);
 104     CPUNios2State *env = &cpu->env;
 105
 106     if ((interrupt_request & CPU_INTERRUPT_HARD) &&
 107         (env->regs[CR_STATUS] & CR_STATUS_PIE)) {
 108         cs->exception_index = EXCP_IRQ;
 109         nios2_cpu_do_interrupt(cs);
 110         return true;
 111     }
 112     return false;
 113 }
 114
 115
 116 static void nios2_cpu_disas_set_info(CPUState *cpu, disassemble_info *info)
 117 {
 118     /* NOTE: NiosII R2 is not supported yet. */
 119     info->mach = bfd_arch_nios2;
 120 #ifdef TARGET_WORDS_BIGENDIAN
 121     info->print_insn = print_insn_big_nios2;
 122 #else
 123     info->print_insn = print_insn_little_nios2;
 124 #endif
 125 }
 126
 127 static int nios2_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
 128 {
 129     Nios2CPU *cpu = NIOS2_CPU(cs);
 130     CPUClass *cc = CPU_GET_CLASS(cs);
 131     CPUNios2State *env = &cpu->env;
 132
 133     if (n > cc->gdb_num_core_regs) {
 134         return 0;
 135     }
 136
 137     if (n < 32) {          /* GP regs */
 138         return gdb_get_reg32(mem_buf, env->regs[n]);
 139     } else if (n == 32) {    /* PC */
 140         return gdb_get_reg32(mem_buf, env->regs[R_PC]);
 141     } else if (n < 49) {     /* Status regs */
 142         return gdb_get_reg32(mem_buf, env->regs[n - 1]);
 143     }
 144
 145     /* Invalid regs */
 146     return 0;
 147 }
 148
 149 static int nios2_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
 150 {
 151     Nios2CPU *cpu = NIOS2_CPU(cs);
 152     CPUClass *cc = CPU_GET_CLASS(cs);
 153     CPUNios2State *env = &cpu->env;
 154
 155     if (n > cc->gdb_num_core_regs) {
 156         return 0;
 157     }
 158
 159     if (n < 32) {            /* GP regs */
 160         env->regs[n] = ldl_p(mem_buf);
 161     } else if (n == 32) {    /* PC */
 162         env->regs[R_PC] = ldl_p(mem_buf);
 163     } else if (n < 49) {     /* Status regs */
 164         env->regs[n - 1] = ldl_p(mem_buf);
 165     }
 166
 167     return 4;
 168 }
 169
 170 static Property nios2_properties[] = {
 171     DEFINE_PROP_BOOL("mmu_present", Nios2CPU, mmu_present, true),
 172     /* ALTR,pid-num-bits */
 173     DEFINE_PROP_UINT32("mmu_pid_num_bits", Nios2CPU, pid_num_bits, 8),
 174     /* ALTR,tlb-num-ways */
 175     DEFINE_PROP_UINT32("mmu_tlb_num_ways", Nios2CPU, tlb_num_ways, 16),
 176     /* ALTR,tlb-num-entries */
 177     DEFINE_PROP_UINT32("mmu_pid_num_entries", Nios2CPU, tlb_num_entries, 256),
 178     DEFINE_PROP_END_OF_LIST(),
 179 };
 180
 181
 182 static void nios2_cpu_class_init(ObjectClass *oc, void *data)
 183 {
 184     DeviceClass *dc = DEVICE_CLASS(oc);
 185     CPUClass *cc = CPU_CLASS(oc);
 186     Nios2CPUClass *ncc = NIOS2_CPU_CLASS(oc);
 187
 188     device_class_set_parent_realize(dc, nios2_cpu_realizefn,
 189                                     &ncc->parent_realize);
 190     dc->props = nios2_properties;
 191     ncc->parent_reset = cc->reset;
 192     cc->reset = nios2_cpu_reset;
 193
 194     cc->class_by_name = nios2_cpu_class_by_name;
 195     cc->has_work = nios2_cpu_has_work;
 196     cc->do_interrupt = nios2_cpu_do_interrupt;
 197     cc->cpu_exec_interrupt = nios2_cpu_exec_interrupt;
 198     cc->dump_state = nios2_cpu_dump_state;
 199     cc->set_pc = nios2_cpu_set_pc;
 200     cc->disas_set_info = nios2_cpu_disas_set_info;
 201     cc->tlb_fill = nios2_cpu_tlb_fill;
 202 #ifndef CONFIG_USER_ONLY
 203     cc->do_unaligned_access = nios2_cpu_do_unaligned_access;
 204     cc->get_phys_page_debug = nios2_cpu_get_phys_page_debug;
 205 #endif
 206     cc->gdb_read_register = nios2_cpu_gdb_read_register;
 207     cc->gdb_write_register = nios2_cpu_gdb_write_register;
 208     cc->gdb_num_core_regs = 49;
 209     cc->tcg_initialize = nios2_tcg_init;
 210 }
 211
 212 static const TypeInfo nios2_cpu_type_info = {
 213     .name = TYPE_NIOS2_CPU,
 214     .parent = TYPE_CPU,
 215     .instance_size = sizeof(Nios2CPU),
 216     .instance_init = nios2_cpu_initfn,
 217     .class_size = sizeof(Nios2CPUClass),
 218     .class_init = nios2_cpu_class_init,
 219 };
 220
 221 static void nios2_cpu_register_types(void)
 222 {
 223     type_register_static(&nios2_cpu_type_info);
 224 }
 225
 226 type_init(nios2_cpu_register_types)