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 #define ppc_num_regs 71
  27
  28 /* Currently, don't check/send MQ.  */
  29 static int ppc_regmap[] =
  30  {PT_R0 * 4,     PT_R1 * 4,     PT_R2 * 4,     PT_R3 * 4,
  31   PT_R4 * 4,     PT_R5 * 4,     PT_R6 * 4,     PT_R7 * 4,
  32   PT_R8 * 4,     PT_R9 * 4,     PT_R10 * 4,    PT_R11 * 4,
  33   PT_R12 * 4,    PT_R13 * 4,    PT_R14 * 4,    PT_R15 * 4,
  34   PT_R16 * 4,    PT_R17 * 4,    PT_R18 * 4,    PT_R19 * 4,
  35   PT_R20 * 4,    PT_R21 * 4,    PT_R22 * 4,    PT_R23 * 4,
  36   PT_R24 * 4,    PT_R25 * 4,    PT_R26 * 4,    PT_R27 * 4,
  37   PT_R28 * 4,    PT_R29 * 4,    PT_R30 * 4,    PT_R31 * 4,
  38 #ifdef __SPE__
  39   -1,            -1,            -1,            -1,
  40   -1,            -1,            -1,            -1,
  41   -1,            -1,            -1,            -1,
  42   -1,            -1,            -1,            -1,
  43   -1,            -1,            -1,            -1,
  44   -1,            -1,            -1,            -1,
  45   -1,            -1,            -1,            -1,
  46   -1,            -1,            -1,            -1,
  47 #else
  48   PT_FPR0*4,     PT_FPR0*4 + 8, PT_FPR0*4+16,  PT_FPR0*4+24,
  49   PT_FPR0*4+32,  PT_FPR0*4+40,  PT_FPR0*4+48,  PT_FPR0*4+56,
  50   PT_FPR0*4+64,  PT_FPR0*4+72,  PT_FPR0*4+80,  PT_FPR0*4+88,
  51   PT_FPR0*4+96,  PT_FPR0*4+104,  PT_FPR0*4+112,  PT_FPR0*4+120,
  52   PT_FPR0*4+128, PT_FPR0*4+136,  PT_FPR0*4+144,  PT_FPR0*4+152,
  53   PT_FPR0*4+160,  PT_FPR0*4+168,  PT_FPR0*4+176,  PT_FPR0*4+184,
  54   PT_FPR0*4+192,  PT_FPR0*4+200,  PT_FPR0*4+208,  PT_FPR0*4+216,
  55   PT_FPR0*4+224,  PT_FPR0*4+232,  PT_FPR0*4+240,  PT_FPR0*4+248,
  56 #endif
  57   PT_NIP * 4,    PT_MSR * 4,    PT_CCR * 4,    PT_LNK * 4,
  58 #ifdef __SPE__
  59   PT_CTR * 4,    PT_XER * 4,    -1
  60 #else
  61   PT_CTR * 4,    PT_XER * 4,    PT_FPSCR * 4
  62 #endif
  63  };
  64
  65 static int
  66 ppc_cannot_store_register (int regno)
  67 {
  68 #ifndef __SPE__
  69   /* Some kernels do not allow us to store fpscr.  */
  70   if (regno == find_regno ("fpscr"))
  71     return 2;
  72 #endif
  73
  74   return 0;
  75 }
  76
  77 static int
  78 ppc_cannot_fetch_register (int regno)
  79 {
  80   return 0;
  81 }
  82
  83 static CORE_ADDR
  84 ppc_get_pc (void)
  85 {
  86   unsigned long pc;
  87
  88   collect_register_by_name ("pc", &pc);
  89   return (CORE_ADDR) pc;
  90 }
  91
  92 static void
  93 ppc_set_pc (CORE_ADDR pc)
  94 {
  95   unsigned long newpc = pc;
  96
  97   supply_register_by_name ("pc", &newpc);
  98 }
  99
 100 /* Correct in either endianness.  Note that this file is
 101    for PowerPC only, not PowerPC64.
 102    This instruction is "twge r2, r2", which GDB uses as a software
 103    breakpoint.  */
 104 static const unsigned long ppc_breakpoint = 0x7d821008;
 105 #define ppc_breakpoint_len 4
 106
 107 static int
 108 ppc_breakpoint_at (CORE_ADDR where)
 109 {
 110   unsigned long insn;
 111
 112   (*the_target->read_memory) (where, (unsigned char *) &insn, 4);
 113   if (insn == ppc_breakpoint)
 114     return 1;
 115   /* If necessary, recognize more trap instructions here.  GDB only uses the
 116      one.  */
 117   return 0;
 118 }
 119
 120 /* Provide only a fill function for the general register set.  ps_lgetregs
 121    will use this for NPTL support.  */
 122
 123 static void ppc_fill_gregset (void *buf)
 124 {
 125   int i;
 126
 127   for (i = 0; i < 32; i++)
 128     collect_register (i, (char *) buf + ppc_regmap[i]);
 129
 130   for (i = 64; i < 70; i++)
 131     collect_register (i, (char *) buf + ppc_regmap[i]);
 132 }
 133
 134 #ifdef __ALTIVEC__
 135
 136 #ifndef PTRACE_GETVRREGS
 137 #define PTRACE_GETVRREGS 18
 138 #define PTRACE_SETVRREGS 19
 139 #endif
 140
 141 #define SIZEOF_VRREGS 33*16+4
 142
 143 static void
 144 ppc_fill_vrregset (void *buf)
 145 {
 146   int i, base;
 147   char *regset = buf;
 148
 149   base = find_regno ("vr0");
 150   for (i = 0; i < 32; i++)
 151     collect_register (base + i, &regset[i * 16]);
 152
 153   collect_register_by_name ("vscr", &regset[32 * 16 + 12]);
 154   collect_register_by_name ("vrsave", &regset[33 * 16]);
 155 }
 156
 157 static void
 158 ppc_store_vrregset (const void *buf)
 159 {
 160   int i, base;
 161   const char *regset = buf;
 162
 163   base = find_regno ("vr0");
 164   for (i = 0; i < 32; i++)
 165     supply_register (base + i, &regset[i * 16]);
 166
 167   supply_register_by_name ("vscr", &regset[32 * 16 + 12]);
 168   supply_register_by_name ("vrsave", &regset[33 * 16]);
 169 }
 170
 171 #endif /* __ALTIVEC__ */
 172
 173 #ifdef __SPE__
 174
 175 #ifndef PTRACE_GETEVRREGS
 176 #define PTRACE_GETEVRREGS       20
 177 #define PTRACE_SETEVRREGS       21
 178 #endif
 179
 180 struct gdb_evrregset_t
 181 {
 182   unsigned long evr[32];
 183   unsigned long long acc;
 184   unsigned long spefscr;
 185 };
 186
 187 static void
 188 ppc_fill_evrregset (void *buf)
 189 {
 190   int i, ev0;
 191   struct gdb_evrregset_t *regset = buf;
 192
 193   ev0 = find_regno ("ev0h");
 194   for (i = 0; i < 32; i++)
 195     collect_register (ev0 + i, &regset->evr[i]);
 196
 197   collect_register_by_name ("acc", &regset->acc);
 198   collect_register_by_name ("spefscr", &regset->spefscr);
 199 }
 200
 201 static void
 202 ppc_store_evrregset (const void *buf)
 203 {
 204   int i, ev0;
 205   const struct gdb_evrregset_t *regset = buf;
 206
 207   ev0 = find_regno ("ev0h");
 208   for (i = 0; i < 32; i++)
 209     supply_register (ev0 + i, &regset->evr[i]);
 210
 211   supply_register_by_name ("acc", &regset->acc);
 212   supply_register_by_name ("spefscr", &regset->spefscr);
 213 }
 214 #endif /* __SPE__ */
 215
 216 struct regset_info target_regsets[] = {
 217   /* List the extra register sets before GENERAL_REGS.  That way we will
 218      fetch them every time, but still fall back to PTRACE_PEEKUSER for the
 219      general registers.  Some kernels support these, but not the newer
 220      PPC_PTRACE_GETREGS.  */
 221 #ifdef __ALTIVEC__
 222   { PTRACE_GETVRREGS, PTRACE_SETVRREGS, SIZEOF_VRREGS, EXTENDED_REGS,
 223     ppc_fill_vrregset, ppc_store_vrregset },
 224 #endif
 225 #ifdef __SPE__
 226   { PTRACE_GETEVRREGS, PTRACE_SETEVRREGS, 32 * 4 + 8 + 4, EXTENDED_REGS,
 227     ppc_fill_evrregset, ppc_store_evrregset },
 228 #endif
 229   { 0, 0, 0, GENERAL_REGS, ppc_fill_gregset, NULL },
 230   { 0, 0, -1, -1, NULL, NULL }
 231 };
 232
 233 struct linux_target_ops the_low_target = {
 234   ppc_num_regs,
 235   ppc_regmap,
 236   ppc_cannot_fetch_register,
 237   ppc_cannot_store_register,
 238   ppc_get_pc,
 239   ppc_set_pc,
 240   (const unsigned char *) &ppc_breakpoint,
 241   ppc_breakpoint_len,
 242   NULL,
 243   0,
 244   ppc_breakpoint_at,
 245 };