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 2 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, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street, Fifth Floor,
  21    Boston, MA 02110-1301, USA.  */
  22
  23 #include "server.h"
  24 #include "linux-low.h"
  25
  26 #include <asm/ptrace.h>
  27
  28 #define ppc_num_regs 71
  29
  30 /* We use a constant for FPSCR instead of PT_FPSCR, because
  31    many shipped PPC64 kernels had the wrong value in ptrace.h.  */
  32 static int ppc_regmap[] =
  33  {PT_R0 * 8,     PT_R1 * 8,     PT_R2 * 8,     PT_R3 * 8,
  34   PT_R4 * 8,     PT_R5 * 8,     PT_R6 * 8,     PT_R7 * 8,
  35   PT_R8 * 8,     PT_R9 * 8,     PT_R10 * 8,    PT_R11 * 8,
  36   PT_R12 * 8,    PT_R13 * 8,    PT_R14 * 8,    PT_R15 * 8,
  37   PT_R16 * 8,    PT_R17 * 8,    PT_R18 * 8,    PT_R19 * 8,
  38   PT_R20 * 8,    PT_R21 * 8,    PT_R22 * 8,    PT_R23 * 8,
  39   PT_R24 * 8,    PT_R25 * 8,    PT_R26 * 8,    PT_R27 * 8,
  40   PT_R28 * 8,    PT_R29 * 8,    PT_R30 * 8,    PT_R31 * 8,
  41   PT_FPR0*8,     PT_FPR0*8 + 8, PT_FPR0*8+16,  PT_FPR0*8+24,
  42   PT_FPR0*8+32,  PT_FPR0*8+40,  PT_FPR0*8+48,  PT_FPR0*8+56,
  43   PT_FPR0*8+64,  PT_FPR0*8+72,  PT_FPR0*8+80,  PT_FPR0*8+88,
  44   PT_FPR0*8+96,  PT_FPR0*8+104,  PT_FPR0*8+112,  PT_FPR0*8+120,
  45   PT_FPR0*8+128, PT_FPR0*8+136,  PT_FPR0*8+144,  PT_FPR0*8+152,
  46   PT_FPR0*8+160,  PT_FPR0*8+168,  PT_FPR0*8+176,  PT_FPR0*8+184,
  47   PT_FPR0*8+192,  PT_FPR0*8+200,  PT_FPR0*8+208,  PT_FPR0*8+216,
  48   PT_FPR0*8+224,  PT_FPR0*8+232,  PT_FPR0*8+240,  PT_FPR0*8+248,
  49   PT_NIP * 8,    PT_MSR * 8,    PT_CCR * 8,    PT_LNK * 8,
  50   PT_CTR * 8,    PT_XER * 8,    PT_FPR0*8 + 256 };
  51
  52 static int
  53 ppc_cannot_store_register (int regno)
  54 {
  55   return 0;
  56 }
  57
  58 static int
  59 ppc_cannot_fetch_register (int regno)
  60 {
  61   return 0;
  62 }
  63
  64 static CORE_ADDR
  65 ppc_get_pc (void)
  66 {
  67   unsigned long pc;
  68
  69   collect_register_by_name ("pc", &pc);
  70   return (CORE_ADDR) pc;
  71 }
  72
  73 static void
  74 ppc_set_pc (CORE_ADDR pc)
  75 {
  76   unsigned long newpc = pc;
  77
  78   supply_register_by_name ("pc", &newpc);
  79 }
  80
  81 /* Correct in either endianness.
  82    This instruction is "twge r2, r2", which GDB uses as a software
  83    breakpoint.  */
  84 static const unsigned int ppc_breakpoint = 0x7d821008;
  85 #define ppc_breakpoint_len 4
  86
  87 static int
  88 ppc_breakpoint_at (CORE_ADDR where)
  89 {
  90   unsigned int insn;
  91
  92   (*the_target->read_memory) (where, (unsigned char *) &insn, 4);
  93   if (insn == ppc_breakpoint)
  94     return 1;
  95   /* If necessary, recognize more trap instructions here.  GDB only uses the
  96      one.  */
  97   return 0;
  98 }
  99
 100 /* Provide only a fill function for the general register set.  ps_lgetregs
 101    will use this for NPTL support.  */
 102
 103 static void ppc_fill_gregset (void *buf)
 104 {
 105   int i;
 106
 107   for (i = 0; i < 32; i++)
 108     collect_register (i, (char *) buf + ppc_regmap[i]);
 109
 110   for (i = 64; i < 70; i++)
 111     collect_register (i, (char *) buf + ppc_regmap[i]);
 112 }
 113
 114 struct regset_info target_regsets[] = {
 115   { 0, 0, 0, GENERAL_REGS, ppc_fill_gregset, NULL },
 116   { 0, 0, -1, -1, NULL, NULL }
 117 };
 118
 119 struct linux_target_ops the_low_target = {
 120   ppc_num_regs,
 121   ppc_regmap,
 122   ppc_cannot_fetch_register,
 123   ppc_cannot_store_register,
 124   ppc_get_pc,
 125   ppc_set_pc,
 126   (const unsigned char *) &ppc_breakpoint,
 127   ppc_breakpoint_len,
 128   NULL,
 129   0,
 130   ppc_breakpoint_at,
 131   NULL,
 132   NULL,
 133   NULL,
 134   NULL,
 135   1
 136 };