gdb/gdbserver/linux-ppc-low.c

   1 /* GNU/Linux/PowerPC specific low level interface, for the remote server for
   2    GDB.
   3    Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2005, 2007, 2008
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "server.h"
  22 #include "linux-low.h"
  23
  24 #include <asm/ptrace.h>
  25
  26 /* Defined in auto-generated file reg-ppc.c.  */
  27 void init_registers_ppc (void);
  28 /* Defined in auto-generated file powerpc-32.c.  */
  29 void init_registers_powerpc_32 (void);
  30 /* Defined in auto-generated file powerpc-e500.c.  */
  31 void init_registers_powerpc_e500 (void);
  32 /* Defined in auto-generated file reg-ppc64.c.  */
  33 void init_registers_ppc64 (void);
  34 /* Defined in auto-generated file powerpc-64.c.  */
  35 void init_registers_powerpc_64 (void);
  36
  37 #define ppc_num_regs 71
  38
  39 #ifdef __powerpc64__
  40 /* We use a constant for FPSCR instead of PT_FPSCR, because
  41    many shipped PPC64 kernels had the wrong value in ptrace.h.  */
  42 static int ppc_regmap[] =
  43  {PT_R0 * 8,     PT_R1 * 8,     PT_R2 * 8,     PT_R3 * 8,
  44   PT_R4 * 8,     PT_R5 * 8,     PT_R6 * 8,     PT_R7 * 8,
  45   PT_R8 * 8,     PT_R9 * 8,     PT_R10 * 8,    PT_R11 * 8,
  46   PT_R12 * 8,    PT_R13 * 8,    PT_R14 * 8,    PT_R15 * 8,
  47   PT_R16 * 8,    PT_R17 * 8,    PT_R18 * 8,    PT_R19 * 8,
  48   PT_R20 * 8,    PT_R21 * 8,    PT_R22 * 8,    PT_R23 * 8,
  49   PT_R24 * 8,    PT_R25 * 8,    PT_R26 * 8,    PT_R27 * 8,
  50   PT_R28 * 8,    PT_R29 * 8,    PT_R30 * 8,    PT_R31 * 8,
  51   PT_FPR0*8,     PT_FPR0*8 + 8, PT_FPR0*8+16,  PT_FPR0*8+24,
  52   PT_FPR0*8+32,  PT_FPR0*8+40,  PT_FPR0*8+48,  PT_FPR0*8+56,
  53   PT_FPR0*8+64,  PT_FPR0*8+72,  PT_FPR0*8+80,  PT_FPR0*8+88,
  54   PT_FPR0*8+96,  PT_FPR0*8+104,  PT_FPR0*8+112,  PT_FPR0*8+120,
  55   PT_FPR0*8+128, PT_FPR0*8+136,  PT_FPR0*8+144,  PT_FPR0*8+152,
  56   PT_FPR0*8+160,  PT_FPR0*8+168,  PT_FPR0*8+176,  PT_FPR0*8+184,
  57   PT_FPR0*8+192,  PT_FPR0*8+200,  PT_FPR0*8+208,  PT_FPR0*8+216,
  58   PT_FPR0*8+224,  PT_FPR0*8+232,  PT_FPR0*8+240,  PT_FPR0*8+248,
  59   PT_NIP * 8,    PT_MSR * 8,    PT_CCR * 8,    PT_LNK * 8,
  60   PT_CTR * 8,    PT_XER * 8,    PT_FPR0*8 + 256 };
  61 #else
  62 /* Currently, don't check/send MQ.  */
  63 static int ppc_regmap[] =
  64  {PT_R0 * 4,     PT_R1 * 4,     PT_R2 * 4,     PT_R3 * 4,
  65   PT_R4 * 4,     PT_R5 * 4,     PT_R6 * 4,     PT_R7 * 4,
  66   PT_R8 * 4,     PT_R9 * 4,     PT_R10 * 4,    PT_R11 * 4,
  67   PT_R12 * 4,    PT_R13 * 4,    PT_R14 * 4,    PT_R15 * 4,
  68   PT_R16 * 4,    PT_R17 * 4,    PT_R18 * 4,    PT_R19 * 4,
  69   PT_R20 * 4,    PT_R21 * 4,    PT_R22 * 4,    PT_R23 * 4,
  70   PT_R24 * 4,    PT_R25 * 4,    PT_R26 * 4,    PT_R27 * 4,
  71   PT_R28 * 4,    PT_R29 * 4,    PT_R30 * 4,    PT_R31 * 4,
  72 #ifdef __SPE__
  73   -1,            -1,            -1,            -1,
  74   -1,            -1,            -1,            -1,
  75   -1,            -1,            -1,            -1,
  76   -1,            -1,            -1,            -1,
  77   -1,            -1,            -1,            -1,
  78   -1,            -1,            -1,            -1,
  79   -1,            -1,            -1,            -1,
  80   -1,            -1,            -1,            -1,
  81 #else
  82   PT_FPR0*4,     PT_FPR0*4 + 8, PT_FPR0*4+16,  PT_FPR0*4+24,
  83   PT_FPR0*4+32,  PT_FPR0*4+40,  PT_FPR0*4+48,  PT_FPR0*4+56,
  84   PT_FPR0*4+64,  PT_FPR0*4+72,  PT_FPR0*4+80,  PT_FPR0*4+88,
  85   PT_FPR0*4+96,  PT_FPR0*4+104,  PT_FPR0*4+112,  PT_FPR0*4+120,
  86   PT_FPR0*4+128, PT_FPR0*4+136,  PT_FPR0*4+144,  PT_FPR0*4+152,
  87   PT_FPR0*4+160,  PT_FPR0*4+168,  PT_FPR0*4+176,  PT_FPR0*4+184,
  88   PT_FPR0*4+192,  PT_FPR0*4+200,  PT_FPR0*4+208,  PT_FPR0*4+216,
  89   PT_FPR0*4+224,  PT_FPR0*4+232,  PT_FPR0*4+240,  PT_FPR0*4+248,
  90 #endif
  91   PT_NIP * 4,    PT_MSR * 4,    PT_CCR * 4,    PT_LNK * 4,
  92 #ifdef __SPE__
  93   PT_CTR * 4,    PT_XER * 4,    -1
  94 #else
  95   PT_CTR * 4,    PT_XER * 4,    PT_FPSCR * 4
  96 #endif
  97  };
  98 #endif
  99
 100 static int
 101 ppc_cannot_store_register (int regno)
 102 {
 103 #if !defined (__powerpc64__) && !defined (__SPE__)
 104   /* Some kernels do not allow us to store fpscr.  */
 105   if (regno == find_regno ("fpscr"))
 106     return 2;
 107 #endif
 108
 109   return 0;
 110 }
 111
 112 static int
 113 ppc_cannot_fetch_register (int regno)
 114 {
 115   return 0;
 116 }
 117
 118 static void
 119 ppc_collect_ptrace_register (int regno, char *buf)
 120 {
 121   int size = register_size (regno);
 122   if (size < sizeof (long))
 123     collect_register (regno, buf + sizeof (long) - size);
 124   else
 125     collect_register (regno, buf);
 126 }
 127
 128 static void
 129 ppc_supply_ptrace_register (int regno, const char *buf)
 130 {
 131   int size = register_size (regno);
 132   if (size < sizeof (long))
 133     supply_register (regno, buf + sizeof (long) - size);
 134   else
 135     supply_register (regno, buf);
 136 }
 137
 138 static CORE_ADDR
 139 ppc_get_pc (void)
 140 {
 141   if (register_size (0) == 4)
 142     {
 143       unsigned int pc;
 144       collect_register_by_name ("pc", &pc);
 145       return (CORE_ADDR) pc;
 146     }
 147   else
 148     {
 149       unsigned long pc;
 150       collect_register_by_name ("pc", &pc);
 151       return (CORE_ADDR) pc;
 152     }
 153 }
 154
 155 static void
 156 ppc_set_pc (CORE_ADDR pc)
 157 {
 158   if (register_size (0) == 4)
 159     {
 160       unsigned int newpc = pc;
 161       supply_register_by_name ("pc", &newpc);
 162     }
 163   else
 164     {
 165       unsigned long newpc = pc;
 166       supply_register_by_name ("pc", &newpc);
 167     }
 168 }
 169
 170 static void
 171 ppc_arch_setup (void)
 172 {
 173 #ifdef __powerpc64__
 174   long msr;
 175
 176   /* On a 64-bit host, assume 64-bit inferior process.  */
 177 #ifdef __ALTIVEC__
 178   init_registers_powerpc_64 ();
 179 #else
 180   init_registers_ppc64 ();
 181 #endif
 182
 183   /* Only if the high bit of the MSR is set, we actually have
 184      a 64-bit inferior.  */
 185   collect_register_by_name ("msr", &msr);
 186   if (msr < 0)
 187     return;
 188 #endif
 189
 190   /* OK, we have a 32-bit inferior.  */
 191 #ifdef __ALTIVEC__
 192   init_registers_powerpc_32 ();
 193 #else
 194 #ifdef __SPE__
 195   init_registers_powerpc_e500 ();
 196 #else
 197   init_registers_ppc ();
 198 #endif
 199 #endif
 200 }
 201
 202 /* Correct in either endianness.
 203    This instruction is "twge r2, r2", which GDB uses as a software
 204    breakpoint.  */
 205 static const unsigned int ppc_breakpoint = 0x7d821008;
 206 #define ppc_breakpoint_len 4
 207
 208 static int
 209 ppc_breakpoint_at (CORE_ADDR where)
 210 {
 211   unsigned int insn;
 212
 213   (*the_target->read_memory) (where, (unsigned char *) &insn, 4);
 214   if (insn == ppc_breakpoint)
 215     return 1;
 216   /* If necessary, recognize more trap instructions here.  GDB only uses the
 217      one.  */
 218   return 0;
 219 }
 220
 221 /* Provide only a fill function for the general register set.  ps_lgetregs
 222    will use this for NPTL support.  */
 223
 224 static void ppc_fill_gregset (void *buf)
 225 {
 226   int i;
 227
 228   for (i = 0; i < 32; i++)
 229     ppc_collect_ptrace_register (i, (char *) buf + ppc_regmap[i]);
 230
 231   for (i = 64; i < 70; i++)
 232     ppc_collect_ptrace_register (i, (char *) buf + ppc_regmap[i]);
 233 }
 234
 235 #ifdef __ALTIVEC__
 236
 237 #ifndef PTRACE_GETVRREGS
 238 #define PTRACE_GETVRREGS 18
 239 #define PTRACE_SETVRREGS 19
 240 #endif
 241
 242 #define SIZEOF_VRREGS 33*16+4
 243
 244 static void
 245 ppc_fill_vrregset (void *buf)
 246 {
 247   int i, base;
 248   char *regset = buf;
 249
 250   base = find_regno ("vr0");
 251   for (i = 0; i < 32; i++)
 252     collect_register (base + i, &regset[i * 16]);
 253
 254   collect_register_by_name ("vscr", &regset[32 * 16 + 12]);
 255   collect_register_by_name ("vrsave", &regset[33 * 16]);
 256 }
 257
 258 static void
 259 ppc_store_vrregset (const void *buf)
 260 {
 261   int i, base;
 262   const char *regset = buf;
 263
 264   base = find_regno ("vr0");
 265   for (i = 0; i < 32; i++)
 266     supply_register (base + i, &regset[i * 16]);
 267
 268   supply_register_by_name ("vscr", &regset[32 * 16 + 12]);
 269   supply_register_by_name ("vrsave", &regset[33 * 16]);
 270 }
 271
 272 #endif /* __ALTIVEC__ */
 273
 274 #ifdef __SPE__
 275
 276 #ifndef PTRACE_GETEVRREGS
 277 #define PTRACE_GETEVRREGS       20
 278 #define PTRACE_SETEVRREGS       21
 279 #endif
 280
 281 struct gdb_evrregset_t
 282 {
 283   unsigned long evr[32];
 284   unsigned long long acc;
 285   unsigned long spefscr;
 286 };
 287
 288 static void
 289 ppc_fill_evrregset (void *buf)
 290 {
 291   int i, ev0;
 292   struct gdb_evrregset_t *regset = buf;
 293
 294   ev0 = find_regno ("ev0h");
 295   for (i = 0; i < 32; i++)
 296     collect_register (ev0 + i, &regset->evr[i]);
 297
 298   collect_register_by_name ("acc", &regset->acc);
 299   collect_register_by_name ("spefscr", &regset->spefscr);
 300 }
 301
 302 static void
 303 ppc_store_evrregset (const void *buf)
 304 {
 305   int i, ev0;
 306   const struct gdb_evrregset_t *regset = buf;
 307
 308   ev0 = find_regno ("ev0h");
 309   for (i = 0; i < 32; i++)
 310     supply_register (ev0 + i, &regset->evr[i]);
 311
 312   supply_register_by_name ("acc", &regset->acc);
 313   supply_register_by_name ("spefscr", &regset->spefscr);
 314 }
 315 #endif /* __SPE__ */
 316
 317 struct regset_info target_regsets[] = {
 318   /* List the extra register sets before GENERAL_REGS.  That way we will
 319      fetch them every time, but still fall back to PTRACE_PEEKUSER for the
 320      general registers.  Some kernels support these, but not the newer
 321      PPC_PTRACE_GETREGS.  */
 322 #ifdef __ALTIVEC__
 323   { PTRACE_GETVRREGS, PTRACE_SETVRREGS, SIZEOF_VRREGS, EXTENDED_REGS,
 324     ppc_fill_vrregset, ppc_store_vrregset },
 325 #endif
 326 #ifdef __SPE__
 327   { PTRACE_GETEVRREGS, PTRACE_SETEVRREGS, 32 * 4 + 8 + 4, EXTENDED_REGS,
 328     ppc_fill_evrregset, ppc_store_evrregset },
 329 #endif
 330   { 0, 0, 0, GENERAL_REGS, ppc_fill_gregset, NULL },
 331   { 0, 0, -1, -1, NULL, NULL }
 332 };
 333
 334 struct linux_target_ops the_low_target = {
 335   ppc_arch_setup,
 336   ppc_num_regs,
 337   ppc_regmap,
 338   ppc_cannot_fetch_register,
 339   ppc_cannot_store_register,
 340   ppc_get_pc,
 341   ppc_set_pc,
 342   (const unsigned char *) &ppc_breakpoint,
 343   ppc_breakpoint_len,
 344   NULL,
 345   0,
 346   ppc_breakpoint_at,
 347   NULL,
 348   NULL,
 349   NULL,
 350   NULL,
 351   ppc_collect_ptrace_register,
 352   ppc_supply_ptrace_register,
 353 };