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 "config.h"
  21 #include "qemu-common.h"
  22 #include "exec/gdbstub.h"
  23
  24 static int ppc_gdb_register_len_apple(int n)
  25 {
  26     switch (n) {
  27     case 0 ... 31:
  28         /* gprs */
  29         return 8;
  30     case 32 ... 63:
  31         /* fprs */
  32         return 8;
  33     case 64 ... 95:
  34         return 16;
  35     case 64+32: /* nip */
  36     case 65+32: /* msr */
  37     case 67+32: /* lr */
  38     case 68+32: /* ctr */
  39     case 69+32: /* xer */
  40     case 70+32: /* fpscr */
  41         return 8;
  42     case 66+32: /* cr */
  43         return 4;
  44     default:
  45         return 0;
  46     }
  47 }
  48
  49 static int ppc_gdb_register_len(int n)
  50 {
  51     switch (n) {
  52     case 0 ... 31:
  53         /* gprs */
  54         return sizeof(target_ulong);
  55     case 32 ... 63:
  56         /* fprs */
  57         if (gdb_has_xml) {
  58             return 0;
  59         }
  60         return 8;
  61     case 66:
  62         /* cr */
  63         return 4;
  64     case 64:
  65         /* nip */
  66     case 65:
  67         /* msr */
  68     case 67:
  69         /* lr */
  70     case 68:
  71         /* ctr */
  72     case 69:
  73         /* xer */
  74         return sizeof(target_ulong);
  75     case 70:
  76         /* fpscr */
  77         if (gdb_has_xml) {
  78             return 0;
  79         }
  80         return sizeof(target_ulong);
  81     default:
  82         return 0;
  83     }
  84 }
  85
  86 /* We need to present the registers to gdb in the "current" memory ordering.
  87    For user-only mode we get this for free; TARGET_WORDS_BIGENDIAN is set to
  88    the proper ordering for the binary, and cannot be changed.
  89    For system mode, TARGET_WORDS_BIGENDIAN is always set, and we must check
  90    the current mode of the chip to see if we're running in little-endian.  */
  91 static void maybe_bswap_register(CPUPPCState *env, uint8_t *mem_buf, int len)
  92 {
  93 #ifndef CONFIG_USER_ONLY
  94     if (!msr_le) {
  95         /* do nothing */
  96     } else if (len == 4) {
  97         bswap32s((uint32_t *)mem_buf);
  98     } else if (len == 8) {
  99         bswap64s((uint64_t *)mem_buf);
 100     } else {
 101         g_assert_not_reached();
 102     }
 103 #endif
 104 }
 105
 106 /* Old gdb always expects FP registers.  Newer (xml-aware) gdb only
 107  * expects whatever the target description contains.  Due to a
 108  * historical mishap the FP registers appear in between core integer
 109  * regs and PC, MSR, CR, and so forth.  We hack round this by giving the
 110  * FP regs zero size when talking to a newer gdb.
 111  */
 112
 113 int ppc_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
 114 {
 115     PowerPCCPU *cpu = POWERPC_CPU(cs);
 116     CPUPPCState *env = &cpu->env;
 117     int r = ppc_gdb_register_len(n);
 118
 119     if (!r) {
 120         return r;
 121     }
 122
 123     if (n < 32) {
 124         /* gprs */
 125         gdb_get_regl(mem_buf, env->gpr[n]);
 126     } else if (n < 64) {
 127         /* fprs */
 128         stfq_p(mem_buf, env->fpr[n-32]);
 129     } else {
 130         switch (n) {
 131         case 64:
 132             gdb_get_regl(mem_buf, env->nip);
 133             break;
 134         case 65:
 135             gdb_get_regl(mem_buf, env->msr);
 136             break;
 137         case 66:
 138             {
 139                 uint32_t cr = 0;
 140                 int i;
 141                 for (i = 0; i < 8; i++) {
 142                     cr |= env->crf[i] << (32 - ((i + 1) * 4));
 143                 }
 144                 gdb_get_reg32(mem_buf, cr);
 145                 break;
 146             }
 147         case 67:
 148             gdb_get_regl(mem_buf, env->lr);
 149             break;
 150         case 68:
 151             gdb_get_regl(mem_buf, env->ctr);
 152             break;
 153         case 69:
 154             gdb_get_regl(mem_buf, env->xer);
 155             break;
 156         case 70:
 157             gdb_get_reg32(mem_buf, env->fpscr);
 158             break;
 159         }
 160     }
 161     maybe_bswap_register(env, mem_buf, r);
 162     return r;
 163 }
 164
 165 int ppc_cpu_gdb_read_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
 166 {
 167     PowerPCCPU *cpu = POWERPC_CPU(cs);
 168     CPUPPCState *env = &cpu->env;
 169     int r = ppc_gdb_register_len_apple(n);
 170
 171     if (!r) {
 172         return r;
 173     }
 174
 175     if (n < 32) {
 176         /* gprs */
 177         gdb_get_reg64(mem_buf, env->gpr[n]);
 178     } else if (n < 64) {
 179         /* fprs */
 180         stfq_p(mem_buf, env->fpr[n-32]);
 181     } else if (n < 96) {
 182         /* Altivec */
 183         stq_p(mem_buf, n - 64);
 184         stq_p(mem_buf + 8, 0);
 185     } else {
 186         switch (n) {
 187         case 64 + 32:
 188             gdb_get_reg64(mem_buf, env->nip);
 189             break;
 190         case 65 + 32:
 191             gdb_get_reg64(mem_buf, env->msr);
 192             break;
 193         case 66 + 32:
 194             {
 195                 uint32_t cr = 0;
 196                 int i;
 197                 for (i = 0; i < 8; i++) {
 198                     cr |= env->crf[i] << (32 - ((i + 1) * 4));
 199                 }
 200                 gdb_get_reg32(mem_buf, cr);
 201                 break;
 202             }
 203         case 67 + 32:
 204             gdb_get_reg64(mem_buf, env->lr);
 205             break;
 206         case 68 + 32:
 207             gdb_get_reg64(mem_buf, env->ctr);
 208             break;
 209         case 69 + 32:
 210             gdb_get_reg64(mem_buf, env->xer);
 211             break;
 212         case 70 + 32:
 213             gdb_get_reg64(mem_buf, env->fpscr);
 214             break;
 215         }
 216     }
 217     maybe_bswap_register(env, mem_buf, r);
 218     return r;
 219 }
 220
 221 int ppc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
 222 {
 223     PowerPCCPU *cpu = POWERPC_CPU(cs);
 224     CPUPPCState *env = &cpu->env;
 225     int r = ppc_gdb_register_len(n);
 226
 227     if (!r) {
 228         return r;
 229     }
 230     maybe_bswap_register(env, mem_buf, r);
 231     if (n < 32) {
 232         /* gprs */
 233         env->gpr[n] = ldtul_p(mem_buf);
 234     } else if (n < 64) {
 235         /* fprs */
 236         env->fpr[n-32] = ldfq_p(mem_buf);
 237     } else {
 238         switch (n) {
 239         case 64:
 240             env->nip = ldtul_p(mem_buf);
 241             break;
 242         case 65:
 243             ppc_store_msr(env, ldtul_p(mem_buf));
 244             break;
 245         case 66:
 246             {
 247                 uint32_t cr = ldl_p(mem_buf);
 248                 int i;
 249                 for (i = 0; i < 8; i++) {
 250                     env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
 251                 }
 252                 break;
 253             }
 254         case 67:
 255             env->lr = ldtul_p(mem_buf);
 256             break;
 257         case 68:
 258             env->ctr = ldtul_p(mem_buf);
 259             break;
 260         case 69:
 261             env->xer = ldtul_p(mem_buf);
 262             break;
 263         case 70:
 264             /* fpscr */
 265             store_fpscr(env, ldtul_p(mem_buf), 0xffffffff);
 266             break;
 267         }
 268     }
 269     return r;
 270 }
 271 int ppc_cpu_gdb_write_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
 272 {
 273     PowerPCCPU *cpu = POWERPC_CPU(cs);
 274     CPUPPCState *env = &cpu->env;
 275     int r = ppc_gdb_register_len_apple(n);
 276
 277     if (!r) {
 278         return r;
 279     }
 280     maybe_bswap_register(env, mem_buf, r);
 281     if (n < 32) {
 282         /* gprs */
 283         env->gpr[n] = ldq_p(mem_buf);
 284     } else if (n < 64) {
 285         /* fprs */
 286         env->fpr[n-32] = ldfq_p(mem_buf);
 287     } else {
 288         switch (n) {
 289         case 64 + 32:
 290             env->nip = ldq_p(mem_buf);
 291             break;
 292         case 65 + 32:
 293             ppc_store_msr(env, ldq_p(mem_buf));
 294             break;
 295         case 66 + 32:
 296             {
 297                 uint32_t cr = ldl_p(mem_buf);
 298                 int i;
 299                 for (i = 0; i < 8; i++) {
 300                     env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
 301                 }
 302                 break;
 303             }
 304         case 67 + 32:
 305             env->lr = ldq_p(mem_buf);
 306             break;
 307         case 68 + 32:
 308             env->ctr = ldq_p(mem_buf);
 309             break;
 310         case 69 + 32:
 311             env->xer = ldq_p(mem_buf);
 312             break;
 313         case 70 + 32:
 314             /* fpscr */
 315             store_fpscr(env, ldq_p(mem_buf), 0xffffffff);
 316             break;
 317         }
 318     }
 319     return r;
 320 }