target/ppc/gdbstub.c

   1 /*
   2  * PowerPC gdb server stub
   3  *
   4  * Copyright (c) 2003-2005 Fabrice Bellard
   5  * Copyright (c) 2013 SUSE LINUX Products GmbH
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20 #include "qemu/osdep.h"
  21 #include "qemu-common.h"
  22 #include "cpu.h"
  23 #include "exec/gdbstub.h"
  24
  25 static int ppc_gdb_register_len_apple(int n)
  26 {
  27     switch (n) {
  28     case 0 ... 31:
  29         /* gprs */
  30         return 8;
  31     case 32 ... 63:
  32         /* fprs */
  33         return 8;
  34     case 64 ... 95:
  35         return 16;
  36     case 64+32: /* nip */
  37     case 65+32: /* msr */
  38     case 67+32: /* lr */
  39     case 68+32: /* ctr */
  40     case 69+32: /* xer */
  41     case 70+32: /* fpscr */
  42         return 8;
  43     case 66+32: /* cr */
  44         return 4;
  45     default:
  46         return 0;
  47     }
  48 }
  49
  50 static int ppc_gdb_register_len(int n)
  51 {
  52     switch (n) {
  53     case 0 ... 31:
  54         /* gprs */
  55         return sizeof(target_ulong);
  56     case 32 ... 63:
  57         /* fprs */
  58         if (gdb_has_xml) {
  59             return 0;
  60         }
  61         return 8;
  62     case 66:
  63         /* cr */
  64         return 4;
  65     case 64:
  66         /* nip */
  67     case 65:
  68         /* msr */
  69     case 67:
  70         /* lr */
  71     case 68:
  72         /* ctr */
  73     case 69:
  74         /* xer */
  75         return sizeof(target_ulong);
  76     case 70:
  77         /* fpscr */
  78         if (gdb_has_xml) {
  79             return 0;
  80         }
  81         return sizeof(target_ulong);
  82     default:
  83         return 0;
  84     }
  85 }
  86
  87 /* We need to present the registers to gdb in the "current" memory ordering.
  88    For user-only mode we get this for free; TARGET_WORDS_BIGENDIAN is set to
  89    the proper ordering for the binary, and cannot be changed.
  90    For system mode, TARGET_WORDS_BIGENDIAN is always set, and we must check
  91    the current mode of the chip to see if we're running in little-endian.  */
  92 void ppc_maybe_bswap_register(CPUPPCState *env, uint8_t *mem_buf, int len)
  93 {
  94 #ifndef CONFIG_USER_ONLY
  95     if (!msr_le) {
  96         /* do nothing */
  97     } else if (len == 4) {
  98         bswap32s((uint32_t *)mem_buf);
  99     } else if (len == 8) {
 100         bswap64s((uint64_t *)mem_buf);
 101     } else {
 102         g_assert_not_reached();
 103     }
 104 #endif
 105 }
 106
 107 /* Old gdb always expects FP registers.  Newer (xml-aware) gdb only
 108  * expects whatever the target description contains.  Due to a
 109  * historical mishap the FP registers appear in between core integer
 110  * regs and PC, MSR, CR, and so forth.  We hack round this by giving the
 111  * FP regs zero size when talking to a newer gdb.
 112  */
 113
 114 int ppc_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
 115 {
 116     PowerPCCPU *cpu = POWERPC_CPU(cs);
 117     CPUPPCState *env = &cpu->env;
 118     int r = ppc_gdb_register_len(n);
 119
 120     if (!r) {
 121         return r;
 122     }
 123
 124     if (n < 32) {
 125         /* gprs */
 126         gdb_get_regl(mem_buf, env->gpr[n]);
 127     } else if (n < 64) {
 128         /* fprs */
 129         stfq_p(mem_buf, env->fpr[n-32]);
 130     } else {
 131         switch (n) {
 132         case 64:
 133             gdb_get_regl(mem_buf, env->nip);
 134             break;
 135         case 65:
 136             gdb_get_regl(mem_buf, env->msr);
 137             break;
 138         case 66:
 139             {
 140                 uint32_t cr = 0;
 141                 int i;
 142                 for (i = 0; i < 8; i++) {
 143                     cr |= env->crf[i] << (32 - ((i + 1) * 4));
 144                 }
 145                 gdb_get_reg32(mem_buf, cr);
 146                 break;
 147             }
 148         case 67:
 149             gdb_get_regl(mem_buf, env->lr);
 150             break;
 151         case 68:
 152             gdb_get_regl(mem_buf, env->ctr);
 153             break;
 154         case 69:
 155             gdb_get_regl(mem_buf, env->xer);
 156             break;
 157         case 70:
 158             gdb_get_reg32(mem_buf, env->fpscr);
 159             break;
 160         }
 161     }
 162     ppc_maybe_bswap_register(env, mem_buf, r);
 163     return r;
 164 }
 165
 166 int ppc_cpu_gdb_read_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
 167 {
 168     PowerPCCPU *cpu = POWERPC_CPU(cs);
 169     CPUPPCState *env = &cpu->env;
 170     int r = ppc_gdb_register_len_apple(n);
 171
 172     if (!r) {
 173         return r;
 174     }
 175
 176     if (n < 32) {
 177         /* gprs */
 178         gdb_get_reg64(mem_buf, env->gpr[n]);
 179     } else if (n < 64) {
 180         /* fprs */
 181         stfq_p(mem_buf, env->fpr[n-32]);
 182     } else if (n < 96) {
 183         /* Altivec */
 184         stq_p(mem_buf, n - 64);
 185         stq_p(mem_buf + 8, 0);
 186     } else {
 187         switch (n) {
 188         case 64 + 32:
 189             gdb_get_reg64(mem_buf, env->nip);
 190             break;
 191         case 65 + 32:
 192             gdb_get_reg64(mem_buf, env->msr);
 193             break;
 194         case 66 + 32:
 195             {
 196                 uint32_t cr = 0;
 197                 int i;
 198                 for (i = 0; i < 8; i++) {
 199                     cr |= env->crf[i] << (32 - ((i + 1) * 4));
 200                 }
 201                 gdb_get_reg32(mem_buf, cr);
 202                 break;
 203             }
 204         case 67 + 32:
 205             gdb_get_reg64(mem_buf, env->lr);
 206             break;
 207         case 68 + 32:
 208             gdb_get_reg64(mem_buf, env->ctr);
 209             break;
 210         case 69 + 32:
 211             gdb_get_reg64(mem_buf, env->xer);
 212             break;
 213         case 70 + 32:
 214             gdb_get_reg64(mem_buf, env->fpscr);
 215             break;
 216         }
 217     }
 218     ppc_maybe_bswap_register(env, mem_buf, r);
 219     return r;
 220 }
 221
 222 int ppc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
 223 {
 224     PowerPCCPU *cpu = POWERPC_CPU(cs);
 225     CPUPPCState *env = &cpu->env;
 226     int r = ppc_gdb_register_len(n);
 227
 228     if (!r) {
 229         return r;
 230     }
 231     ppc_maybe_bswap_register(env, mem_buf, r);
 232     if (n < 32) {
 233         /* gprs */
 234         env->gpr[n] = ldtul_p(mem_buf);
 235     } else if (n < 64) {
 236         /* fprs */
 237         env->fpr[n-32] = ldfq_p(mem_buf);
 238     } else {
 239         switch (n) {
 240         case 64:
 241             env->nip = ldtul_p(mem_buf);
 242             break;
 243         case 65:
 244             ppc_store_msr(env, ldtul_p(mem_buf));
 245             break;
 246         case 66:
 247             {
 248                 uint32_t cr = ldl_p(mem_buf);
 249                 int i;
 250                 for (i = 0; i < 8; i++) {
 251                     env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
 252                 }
 253                 break;
 254             }
 255         case 67:
 256             env->lr = ldtul_p(mem_buf);
 257             break;
 258         case 68:
 259             env->ctr = ldtul_p(mem_buf);
 260             break;
 261         case 69:
 262             env->xer = ldtul_p(mem_buf);
 263             break;
 264         case 70:
 265             /* fpscr */
 266             store_fpscr(env, ldtul_p(mem_buf), 0xffffffff);
 267             break;
 268         }
 269     }
 270     return r;
 271 }
 272 int ppc_cpu_gdb_write_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
 273 {
 274     PowerPCCPU *cpu = POWERPC_CPU(cs);
 275     CPUPPCState *env = &cpu->env;
 276     int r = ppc_gdb_register_len_apple(n);
 277
 278     if (!r) {
 279         return r;
 280     }
 281     ppc_maybe_bswap_register(env, mem_buf, r);
 282     if (n < 32) {
 283         /* gprs */
 284         env->gpr[n] = ldq_p(mem_buf);
 285     } else if (n < 64) {
 286         /* fprs */
 287         env->fpr[n-32] = ldfq_p(mem_buf);
 288     } else {
 289         switch (n) {
 290         case 64 + 32:
 291             env->nip = ldq_p(mem_buf);
 292             break;
 293         case 65 + 32:
 294             ppc_store_msr(env, ldq_p(mem_buf));
 295             break;
 296         case 66 + 32:
 297             {
 298                 uint32_t cr = ldl_p(mem_buf);
 299                 int i;
 300                 for (i = 0; i < 8; i++) {
 301                     env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
 302                 }
 303                 break;
 304             }
 305         case 67 + 32:
 306             env->lr = ldq_p(mem_buf);
 307             break;
 308         case 68 + 32:
 309             env->ctr = ldq_p(mem_buf);
 310             break;
 311         case 69 + 32:
 312             env->xer = ldq_p(mem_buf);
 313             break;
 314         case 70 + 32:
 315             /* fpscr */
 316             store_fpscr(env, ldq_p(mem_buf), 0xffffffff);
 317             break;
 318         }
 319     }
 320     return r;
 321 }