gdb/gdbserver/linux-tile-low.c

   1 /* GNU/Linux/TILE-Gx specific low level interface, GDBserver.
   2
   3    Copyright (C) 2012-2015 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program 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
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "server.h"
  21 #include "linux-low.h"
  22
  23 #include <arch/abi.h>
  24 #include "nat/gdb_ptrace.h"
  25
  26 /* Defined in auto-generated file reg-tilegx.c.  */
  27 void init_registers_tilegx (void);
  28 extern const struct target_desc *tdesc_tilegx;
  29
  30 /* Defined in auto-generated file reg-tilegx32.c.  */
  31 void init_registers_tilegx32 (void);
  32 extern const struct target_desc *tdesc_tilegx32;
  33
  34 #define tile_num_regs 65
  35
  36 static int tile_regmap[] =
  37 {
  38    0,  1,  2,  3,  4,  5,  6,  7,
  39    8,  9, 10, 11, 12, 13, 14, 15,
  40   16, 17, 18, 19, 20, 21, 22, 23,
  41   24, 25, 26, 27, 28, 29, 30, 31,
  42   32, 33, 34, 35, 36, 37, 38, 39,
  43   40, 41, 42, 43, 44, 45, 46, 47,
  44   48, 49, 50, 51, 52, 53, 54, 55,
  45   -1, -1, -1, -1, -1, -1, -1, -1,
  46   56
  47 };
  48
  49 static int
  50 tile_cannot_fetch_register (int regno)
  51 {
  52   if (regno >= 0 && regno < 56)
  53     return 0;
  54   else if (regno == 64)
  55     return 0;
  56   else
  57     return 1;
  58 }
  59
  60 static int
  61 tile_cannot_store_register (int regno)
  62 {
  63   if (regno >= 0 && regno < 56)
  64     return 0;
  65   else if (regno == 64)
  66     return 0;
  67   else
  68     return 1;
  69 }
  70
  71 static CORE_ADDR
  72 tile_get_pc (struct regcache *regcache)
  73 {
  74   unsigned long pc;
  75
  76   collect_register_by_name (regcache, "pc", &pc);
  77   return pc;
  78 }
  79
  80 static void
  81 tile_set_pc (struct regcache *regcache, CORE_ADDR pc)
  82 {
  83   unsigned long newpc = pc;
  84
  85   supply_register_by_name (regcache, "pc", &newpc);
  86 }
  87
  88 static uint64_t tile_breakpoint = 0x400b3cae70166000ULL;
  89 #define tile_breakpoint_len 8
  90
  91 static int
  92 tile_breakpoint_at (CORE_ADDR where)
  93 {
  94   uint64_t insn;
  95
  96   (*the_target->read_memory) (where, (unsigned char *) &insn, 8);
  97   if (insn == tile_breakpoint)
  98     return 1;
  99
 100   /* If necessary, recognize more trap instructions here.  GDB only uses the
 101      one.  */
 102   return 0;
 103 }
 104
 105 static void
 106 tile_fill_gregset (struct regcache *regcache, void *buf)
 107 {
 108   int i;
 109
 110   for (i = 0; i < tile_num_regs; i++)
 111     if (tile_regmap[i] != -1)
 112       collect_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 113 }
 114
 115 static void
 116 tile_store_gregset (struct regcache *regcache, const void *buf)
 117 {
 118   int i;
 119
 120   for (i = 0; i < tile_num_regs; i++)
 121     if (tile_regmap[i] != -1)
 122       supply_register (regcache, i, ((uint_reg_t *) buf) + tile_regmap[i]);
 123 }
 124
 125 static struct regset_info tile_regsets[] =
 126 {
 127   { PTRACE_GETREGS, PTRACE_SETREGS, 0, tile_num_regs * 8,
 128     GENERAL_REGS, tile_fill_gregset, tile_store_gregset },
 129   { 0, 0, 0, -1, -1, NULL, NULL }
 130 };
 131
 132 static struct regsets_info tile_regsets_info =
 133   {
 134     tile_regsets, /* regsets */
 135     0, /* num_regsets */
 136     NULL, /* disabled_regsets */
 137   };
 138
 139 static struct usrregs_info tile_usrregs_info =
 140   {
 141     tile_num_regs,
 142     tile_regmap,
 143   };
 144
 145 static struct regs_info regs_info =
 146   {
 147     NULL, /* regset_bitmap */
 148     &tile_usrregs_info,
 149     &tile_regsets_info,
 150   };
 151
 152 static const struct regs_info *
 153 tile_regs_info (void)
 154 {
 155   return &regs_info;
 156 }
 157
 158 static void
 159 tile_arch_setup (void)
 160 {
 161   int pid = pid_of (current_thread);
 162   unsigned int machine;
 163   int is_elf64 = linux_pid_exe_is_elf_64_file (pid, &machine);
 164
 165   if (sizeof (void *) == 4)
 166     if (is_elf64 > 0)
 167       error (_("Can't debug 64-bit process with 32-bit GDBserver"));
 168
 169   if (!is_elf64)
 170     current_process ()->tdesc = tdesc_tilegx32;
 171   else
 172     current_process ()->tdesc = tdesc_tilegx;
 173 }
 174
 175
 176 struct linux_target_ops the_low_target =
 177 {
 178   tile_arch_setup,
 179   tile_regs_info,
 180   tile_cannot_fetch_register,
 181   tile_cannot_store_register,
 182   NULL,
 183   tile_get_pc,
 184   tile_set_pc,
 185   (const unsigned char *) &tile_breakpoint,
 186   tile_breakpoint_len,
 187   NULL,
 188   0,
 189   tile_breakpoint_at,
 190 };
 191
 192 void
 193 initialize_low_arch (void)
 194 {
 195   init_registers_tilegx32();
 196   init_registers_tilegx();
 197
 198   initialize_regsets_info (&tile_regsets_info);
 199 }