gdb/gdbserver/linux-ppc64-low.c

   1 /* GNU/Linux/PowerPC64 specific low level interface, for the remote server for
   2    GDB.
   3    Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2005, 2007
   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 /* We use a constant for FPSCR instead of PT_FPSCR, because
  29    many shipped PPC64 kernels had the wrong value in ptrace.h.  */
  30 static int ppc_regmap[] =
  31  {PT_R0 * 8,     PT_R1 * 8,     PT_R2 * 8,     PT_R3 * 8,
  32   PT_R4 * 8,     PT_R5 * 8,     PT_R6 * 8,     PT_R7 * 8,
  33   PT_R8 * 8,     PT_R9 * 8,     PT_R10 * 8,    PT_R11 * 8,
  34   PT_R12 * 8,    PT_R13 * 8,    PT_R14 * 8,    PT_R15 * 8,
  35   PT_R16 * 8,    PT_R17 * 8,    PT_R18 * 8,    PT_R19 * 8,
  36   PT_R20 * 8,    PT_R21 * 8,    PT_R22 * 8,    PT_R23 * 8,
  37   PT_R24 * 8,    PT_R25 * 8,    PT_R26 * 8,    PT_R27 * 8,
  38   PT_R28 * 8,    PT_R29 * 8,    PT_R30 * 8,    PT_R31 * 8,
  39   PT_FPR0*8,     PT_FPR0*8 + 8, PT_FPR0*8+16,  PT_FPR0*8+24,
  40   PT_FPR0*8+32,  PT_FPR0*8+40,  PT_FPR0*8+48,  PT_FPR0*8+56,
  41   PT_FPR0*8+64,  PT_FPR0*8+72,  PT_FPR0*8+80,  PT_FPR0*8+88,
  42   PT_FPR0*8+96,  PT_FPR0*8+104,  PT_FPR0*8+112,  PT_FPR0*8+120,
  43   PT_FPR0*8+128, PT_FPR0*8+136,  PT_FPR0*8+144,  PT_FPR0*8+152,
  44   PT_FPR0*8+160,  PT_FPR0*8+168,  PT_FPR0*8+176,  PT_FPR0*8+184,
  45   PT_FPR0*8+192,  PT_FPR0*8+200,  PT_FPR0*8+208,  PT_FPR0*8+216,
  46   PT_FPR0*8+224,  PT_FPR0*8+232,  PT_FPR0*8+240,  PT_FPR0*8+248,
  47   PT_NIP * 8,    PT_MSR * 8,    PT_CCR * 8,    PT_LNK * 8,
  48   PT_CTR * 8,    PT_XER * 8,    PT_FPR0*8 + 256 };
  49
  50 static int
  51 ppc_cannot_store_register (int regno)
  52 {
  53   return 0;
  54 }
  55
  56 static int
  57 ppc_cannot_fetch_register (int regno)
  58 {
  59   return 0;
  60 }
  61
  62 static CORE_ADDR
  63 ppc_get_pc (void)
  64 {
  65   unsigned long pc;
  66
  67   collect_register_by_name ("pc", &pc);
  68   return (CORE_ADDR) pc;
  69 }
  70
  71 static void
  72 ppc_set_pc (CORE_ADDR pc)
  73 {
  74   unsigned long newpc = pc;
  75
  76   supply_register_by_name ("pc", &newpc);
  77 }
  78
  79 /* Correct in either endianness.
  80    This instruction is "twge r2, r2", which GDB uses as a software
  81    breakpoint.  */
  82 static const unsigned int ppc_breakpoint = 0x7d821008;
  83 #define ppc_breakpoint_len 4
  84
  85 static int
  86 ppc_breakpoint_at (CORE_ADDR where)
  87 {
  88   unsigned int insn;
  89
  90   (*the_target->read_memory) (where, (unsigned char *) &insn, 4);
  91   if (insn == ppc_breakpoint)
  92     return 1;
  93   /* If necessary, recognize more trap instructions here.  GDB only uses the
  94      one.  */
  95   return 0;
  96 }
  97
  98 /* Provide only a fill function for the general register set.  ps_lgetregs
  99    will use this for NPTL support.  */
 100
 101 static void ppc_fill_gregset (void *buf)
 102 {
 103   int i;
 104
 105   for (i = 0; i < 32; i++)
 106     collect_register (i, (char *) buf + ppc_regmap[i]);
 107
 108   for (i = 64; i < 70; i++)
 109     collect_register (i, (char *) buf + ppc_regmap[i]);
 110 }
 111
 112 #ifdef __ALTIVEC__
 113
 114 #ifndef PTRACE_GETVRREGS
 115 #define PTRACE_GETVRREGS 18
 116 #define PTRACE_SETVRREGS 19
 117 #endif
 118
 119 #define SIZEOF_VRREGS 33*16+4
 120
 121 static void
 122 ppc_fill_vrregset (void *buf)
 123 {
 124   int i, base;
 125   char *regset = buf;
 126
 127   base = find_regno ("vr0");
 128   for (i = 0; i < 32; i++)
 129     collect_register (base + i, &regset[i * 16]);
 130
 131   collect_register_by_name ("vscr", &regset[32 * 16 + 12]);
 132   collect_register_by_name ("vrsave", &regset[33 * 16]);
 133 }
 134
 135 static void
 136 ppc_store_vrregset (const void *buf)
 137 {
 138   int i, base;
 139   const char *regset = buf;
 140
 141   base = find_regno ("vr0");
 142   for (i = 0; i < 32; i++)
 143     supply_register (base + i, &regset[i * 16]);
 144
 145   supply_register_by_name ("vscr", &regset[32 * 16 + 12]);
 146   supply_register_by_name ("vrsave", &regset[33 * 16]);
 147 }
 148
 149 #endif /* __ALTIVEC__ */
 150
 151 struct regset_info target_regsets[] = {
 152   /* List the extra register sets before GENERAL_REGS.  That way we will
 153      fetch them every time, but still fall back to PTRACE_PEEKUSER for the
 154      general registers.  Some kernels support these, but not the newer
 155      PPC_PTRACE_GETREGS.  */
 156 #ifdef __ALTIVEC__
 157   { PTRACE_GETVRREGS, PTRACE_SETVRREGS, SIZEOF_VRREGS, EXTENDED_REGS,
 158     ppc_fill_vrregset, ppc_store_vrregset },
 159 #endif
 160   { 0, 0, 0, GENERAL_REGS, ppc_fill_gregset, NULL },
 161   { 0, 0, -1, -1, NULL, NULL }
 162 };
 163
 164 struct linux_target_ops the_low_target = {
 165   ppc_num_regs,
 166   ppc_regmap,
 167   ppc_cannot_fetch_register,
 168   ppc_cannot_store_register,
 169   ppc_get_pc,
 170   ppc_set_pc,
 171   (const unsigned char *) &ppc_breakpoint,
 172   ppc_breakpoint_len,
 173   NULL,
 174   0,
 175   ppc_breakpoint_at,
 176   NULL,
 177   NULL,
 178   NULL,
 179   NULL,
 180   1
 181 };