target/lm32/helper.c

   1 /*
   2  *  LatticeMico32 helper routines.
   3  *
   4  *  Copyright (c) 2010-2014 Michael Walle <michael@walle.cc>
   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 "qemu/host-utils.h"
  24 #include "hw/semihosting/semihost.h"
  25 #include "exec/log.h"
  26
  27 bool lm32_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
  28                        MMUAccessType access_type, int mmu_idx,
  29                        bool probe, uintptr_t retaddr)
  30 {
  31     LM32CPU *cpu = LM32_CPU(cs);
  32     CPULM32State *env = &cpu->env;
  33     int prot;
  34
  35     address &= TARGET_PAGE_MASK;
  36     prot = PAGE_BITS;
  37     if (env->flags & LM32_FLAG_IGNORE_MSB) {
  38         tlb_set_page(cs, address, address & 0x7fffffff, prot, mmu_idx,
  39                      TARGET_PAGE_SIZE);
  40     } else {
  41         tlb_set_page(cs, address, address, prot, mmu_idx, TARGET_PAGE_SIZE);
  42     }
  43     return true;
  44 }
  45
  46 hwaddr lm32_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
  47 {
  48     LM32CPU *cpu = LM32_CPU(cs);
  49
  50     addr &= TARGET_PAGE_MASK;
  51     if (cpu->env.flags & LM32_FLAG_IGNORE_MSB) {
  52         return addr & 0x7fffffff;
  53     } else {
  54         return addr;
  55     }
  56 }
  57
  58 void lm32_breakpoint_insert(CPULM32State *env, int idx, target_ulong address)
  59 {
  60     cpu_breakpoint_insert(env_cpu(env), address, BP_CPU,
  61                           &env->cpu_breakpoint[idx]);
  62 }
  63
  64 void lm32_breakpoint_remove(CPULM32State *env, int idx)
  65 {
  66     if (!env->cpu_breakpoint[idx]) {
  67         return;
  68     }
  69
  70     cpu_breakpoint_remove_by_ref(env_cpu(env), env->cpu_breakpoint[idx]);
  71     env->cpu_breakpoint[idx] = NULL;
  72 }
  73
  74 void lm32_watchpoint_insert(CPULM32State *env, int idx, target_ulong address,
  75                             lm32_wp_t wp_type)
  76 {
  77     int flags = 0;
  78
  79     switch (wp_type) {
  80     case LM32_WP_DISABLED:
  81         /* nothing to do */
  82         break;
  83     case LM32_WP_READ:
  84         flags = BP_CPU | BP_STOP_BEFORE_ACCESS | BP_MEM_READ;
  85         break;
  86     case LM32_WP_WRITE:
  87         flags = BP_CPU | BP_STOP_BEFORE_ACCESS | BP_MEM_WRITE;
  88         break;
  89     case LM32_WP_READ_WRITE:
  90         flags = BP_CPU | BP_STOP_BEFORE_ACCESS | BP_MEM_ACCESS;
  91         break;
  92     }
  93
  94     if (flags != 0) {
  95         cpu_watchpoint_insert(env_cpu(env), address, 1, flags,
  96                               &env->cpu_watchpoint[idx]);
  97     }
  98 }
  99
 100 void lm32_watchpoint_remove(CPULM32State *env, int idx)
 101 {
 102     if (!env->cpu_watchpoint[idx]) {
 103         return;
 104     }
 105
 106     cpu_watchpoint_remove_by_ref(env_cpu(env), env->cpu_watchpoint[idx]);
 107     env->cpu_watchpoint[idx] = NULL;
 108 }
 109
 110 static bool check_watchpoints(CPULM32State *env)
 111 {
 112     LM32CPU *cpu = env_archcpu(env);
 113     int i;
 114
 115     for (i = 0; i < cpu->num_watchpoints; i++) {
 116         if (env->cpu_watchpoint[i] &&
 117                 env->cpu_watchpoint[i]->flags & BP_WATCHPOINT_HIT) {
 118             return true;
 119         }
 120     }
 121     return false;
 122 }
 123
 124 void lm32_debug_excp_handler(CPUState *cs)
 125 {
 126     LM32CPU *cpu = LM32_CPU(cs);
 127     CPULM32State *env = &cpu->env;
 128     CPUBreakpoint *bp;
 129
 130     if (cs->watchpoint_hit) {
 131         if (cs->watchpoint_hit->flags & BP_CPU) {
 132             cs->watchpoint_hit = NULL;
 133             if (check_watchpoints(env)) {
 134                 raise_exception(env, EXCP_WATCHPOINT);
 135             } else {
 136                 cpu_loop_exit_noexc(cs);
 137             }
 138         }
 139     } else {
 140         QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
 141             if (bp->pc == env->pc) {
 142                 if (bp->flags & BP_CPU) {
 143                     raise_exception(env, EXCP_BREAKPOINT);
 144                 }
 145                 break;
 146             }
 147         }
 148     }
 149 }
 150
 151 void lm32_cpu_do_interrupt(CPUState *cs)
 152 {
 153     LM32CPU *cpu = LM32_CPU(cs);
 154     CPULM32State *env = &cpu->env;
 155
 156     qemu_log_mask(CPU_LOG_INT,
 157             "exception at pc=%x type=%x\n", env->pc, cs->exception_index);
 158
 159     switch (cs->exception_index) {
 160     case EXCP_SYSTEMCALL:
 161         if (unlikely(semihosting_enabled())) {
 162             /* do_semicall() returns true if call was handled. Otherwise
 163              * do the normal exception handling. */
 164             if (lm32_cpu_do_semihosting(cs)) {
 165                 env->pc += 4;
 166                 break;
 167             }
 168         }
 169         /* fall through */
 170     case EXCP_INSN_BUS_ERROR:
 171     case EXCP_DATA_BUS_ERROR:
 172     case EXCP_DIVIDE_BY_ZERO:
 173     case EXCP_IRQ:
 174         /* non-debug exceptions */
 175         env->regs[R_EA] = env->pc;
 176         env->ie |= (env->ie & IE_IE) ? IE_EIE : 0;
 177         env->ie &= ~IE_IE;
 178         if (env->dc & DC_RE) {
 179             env->pc = env->deba + (cs->exception_index * 32);
 180         } else {
 181             env->pc = env->eba + (cs->exception_index * 32);
 182         }
 183         log_cpu_state_mask(CPU_LOG_INT, cs, 0);
 184         break;
 185     case EXCP_BREAKPOINT:
 186     case EXCP_WATCHPOINT:
 187         /* debug exceptions */
 188         env->regs[R_BA] = env->pc;
 189         env->ie |= (env->ie & IE_IE) ? IE_BIE : 0;
 190         env->ie &= ~IE_IE;
 191         env->pc = env->deba + (cs->exception_index * 32);
 192         log_cpu_state_mask(CPU_LOG_INT, cs, 0);
 193         break;
 194     default:
 195         cpu_abort(cs, "unhandled exception type=%d\n",
 196                   cs->exception_index);
 197         break;
 198     }
 199 }
 200
 201 bool lm32_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
 202 {
 203     LM32CPU *cpu = LM32_CPU(cs);
 204     CPULM32State *env = &cpu->env;
 205
 206     if ((interrupt_request & CPU_INTERRUPT_HARD) && (env->ie & IE_IE)) {
 207         cs->exception_index = EXCP_IRQ;
 208         lm32_cpu_do_interrupt(cs);
 209         return true;
 210     }
 211     return false;
 212 }
 213
 214 /* Some soc ignores the MSB on the address bus. Thus creating a shadow memory
 215  * area. As a general rule, 0x00000000-0x7fffffff is cached, whereas
 216  * 0x80000000-0xffffffff is not cached and used to access IO devices. */
 217 void cpu_lm32_set_phys_msb_ignore(CPULM32State *env, int value)
 218 {
 219     if (value) {
 220         env->flags |= LM32_FLAG_IGNORE_MSB;
 221     } else {
 222         env->flags &= ~LM32_FLAG_IGNORE_MSB;
 223     }
 224 }