gdb/m32r-linux-nat.c

   1 /* Native-dependent code for GNU/Linux m32r.
   2
   3    Copyright (C) 2004, 2005, 2006, 2007, 2008 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 "defs.h"
  21 #include "inferior.h"
  22 #include "gdbcore.h"
  23 #include "regcache.h"
  24 #include "linux-nat.h"
  25 #include "target.h"
  26
  27 #include "gdb_assert.h"
  28 #include "gdb_string.h"
  29 #include <sys/ptrace.h>
  30 #include <sys/user.h>
  31 #include <sys/procfs.h>
  32
  33 /* Prototypes for supply_gregset etc.  */
  34 #include "gregset.h"
  35
  36 #include "m32r-tdep.h"
  37 \f
  38
  39
  40
  41 /* Since EVB register is not available for native debug, we reduce
  42    the number of registers.  */
  43 #define M32R_LINUX_NUM_REGS (M32R_NUM_REGS - 1)
  44
  45 /* Mapping between the general-purpose registers in `struct user'
  46    format and GDB's register array layout.  */
  47 static int regmap[] = {
  48   4, 5, 6, 7, 0, 1, 2, 8,
  49   9, 10, 11, 12, 13, 24, 25, 23,
  50   19, 19, 26, 23, 22, 20, 16, 15
  51 };
  52
  53 #define PSW_REGMAP 19
  54 #define BBPSW_REGMAP 21
  55 #define SPU_REGMAP 23
  56 #define SPI_REGMAP 26
  57
  58 /* Doee apply to the corresponding SET requests as well.  */
  59 #define GETREGS_SUPPLIES(regno) (0 <= (regno) && (regno) <= M32R_LINUX_NUM_REGS)
  60 \f
  61
  62
  63 /* Transfering the general-purpose registers between GDB, inferiors
  64    and core files.  */
  65
  66 /* Fill GDB's register array with the general-purpose register values
  67    in *GREGSETP.  */
  68
  69 void
  70 supply_gregset (struct regcache *regcache, const elf_gregset_t * gregsetp)
  71 {
  72   const elf_greg_t *regp = (const elf_greg_t *) gregsetp;
  73   int i;
  74   unsigned long psw, bbpsw;
  75
  76   psw = *(regp + PSW_REGMAP);
  77   bbpsw = *(regp + BBPSW_REGMAP);
  78
  79   for (i = 0; i < M32R_LINUX_NUM_REGS; i++)
  80     {
  81       elf_greg_t regval;
  82
  83       switch (i)
  84         {
  85         case PSW_REGNUM:
  86           regval = ((0x00c1 & bbpsw) << 8) | ((0xc100 & psw) >> 8);
  87           break;
  88         case CBR_REGNUM:
  89           regval = ((psw >> 8) & 1);
  90           break;
  91         default:
  92           regval = *(regp + regmap[i]);
  93           break;
  94         }
  95
  96       if (i != M32R_SP_REGNUM)
  97         regcache_raw_supply (regcache, i, &regval);
  98       else if (psw & 0x8000)
  99         regcache_raw_supply (regcache, i, regp + SPU_REGMAP);
 100       else
 101         regcache_raw_supply (regcache, i, regp + SPI_REGMAP);
 102     }
 103 }
 104
 105 /* Fetch all general-purpose registers from process/thread TID and
 106    store their values in GDB's register array.  */
 107
 108 static void
 109 fetch_regs (struct regcache *regcache, int tid)
 110 {
 111   elf_gregset_t regs;
 112
 113   if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
 114     perror_with_name (_("Couldn't get registers"));
 115
 116   supply_gregset (regcache, (const elf_gregset_t *) &regs);
 117 }
 118
 119 /* Fill register REGNO (if it is a general-purpose register) in
 120    *GREGSETPS with the value in GDB's register array.  If REGNO is -1,
 121    do this for all registers.  */
 122
 123 void
 124 fill_gregset (const struct regcache *regcache,
 125               elf_gregset_t * gregsetp, int regno)
 126 {
 127   elf_greg_t *regp = (elf_greg_t *) gregsetp;
 128   int i;
 129   unsigned long psw, bbpsw, tmp;
 130
 131   psw = *(regp + PSW_REGMAP);
 132   bbpsw = *(regp + BBPSW_REGMAP);
 133
 134   for (i = 0; i < M32R_LINUX_NUM_REGS; i++)
 135     {
 136       if (regno != -1 && regno != i)
 137         continue;
 138
 139       if (i == CBR_REGNUM || i == PSW_REGNUM)
 140         continue;
 141
 142       if (i == SPU_REGNUM || i == SPI_REGNUM)
 143         continue;
 144
 145       if (i != M32R_SP_REGNUM)
 146         regcache_raw_collect (regcache, i, regp + regmap[i]);
 147       else if (psw & 0x8000)
 148         regcache_raw_collect (regcache, i, regp + SPU_REGMAP);
 149       else
 150         regcache_raw_collect (regcache, i, regp + SPI_REGMAP);
 151     }
 152 }
 153
 154 /* Store all valid general-purpose registers in GDB's register array
 155    into the process/thread specified by TID.  */
 156
 157 static void
 158 store_regs (const struct regcache *regcache, int tid, int regno)
 159 {
 160   elf_gregset_t regs;
 161
 162   if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
 163     perror_with_name (_("Couldn't get registers"));
 164
 165   fill_gregset (regcache, &regs, regno);
 166
 167   if (ptrace (PTRACE_SETREGS, tid, 0, (int) &regs) < 0)
 168     perror_with_name (_("Couldn't write registers"));
 169 }
 170 \f
 171
 172
 173 /* Transfering floating-point registers between GDB, inferiors and cores.
 174    Since M32R has no floating-point registers, these functions do nothing.  */
 175
 176 void
 177 supply_fpregset (struct regcache *regcache, const gdb_fpregset_t *fpregs)
 178 {
 179 }
 180
 181 void
 182 fill_fpregset (const struct regcache *regcache,
 183                gdb_fpregset_t *fpregs, int regno)
 184 {
 185 }
 186 \f
 187
 188
 189 /* Transferring arbitrary registers between GDB and inferior.  */
 190
 191 /* Fetch register REGNO from the child process.  If REGNO is -1, do
 192    this for all registers (including the floating point and SSE
 193    registers).  */
 194
 195 static void
 196 m32r_linux_fetch_inferior_registers (struct regcache *regcache, int regno)
 197 {
 198   int tid;
 199
 200   /* GNU/Linux LWP ID's are process ID's.  */
 201   tid = TIDGET (inferior_ptid);
 202   if (tid == 0)
 203     tid = PIDGET (inferior_ptid);       /* Not a threaded program.  */
 204
 205   /* Use the PTRACE_GETREGS request whenever possible, since it
 206      transfers more registers in one system call, and we'll cache the
 207      results.  */
 208   if (regno == -1 || GETREGS_SUPPLIES (regno))
 209     {
 210       fetch_regs (regcache, tid);
 211       return;
 212     }
 213
 214   internal_error (__FILE__, __LINE__,
 215                   _("Got request for bad register number %d."), regno);
 216 }
 217
 218 /* Store register REGNO back into the child process.  If REGNO is -1,
 219    do this for all registers (including the floating point and SSE
 220    registers).  */
 221 static void
 222 m32r_linux_store_inferior_registers (struct regcache *regcache, int regno)
 223 {
 224   int tid;
 225
 226   /* GNU/Linux LWP ID's are process ID's.  */
 227   if ((tid = TIDGET (inferior_ptid)) == 0)
 228     tid = PIDGET (inferior_ptid);       /* Not a threaded program.  */
 229
 230   /* Use the PTRACE_SETREGS request whenever possible, since it
 231      transfers more registers in one system call.  */
 232   if (regno == -1 || GETREGS_SUPPLIES (regno))
 233     {
 234       store_regs (regcache, tid, regno);
 235       return;
 236     }
 237
 238   internal_error (__FILE__, __LINE__,
 239                   _("Got request to store bad register number %d."), regno);
 240 }
 241
 242 void _initialize_m32r_linux_nat (void);
 243
 244 void
 245 _initialize_m32r_linux_nat (void)
 246 {
 247   struct target_ops *t;
 248
 249   /* Fill in the generic GNU/Linux methods.  */
 250   t = linux_target ();
 251
 252   /* Add our register access methods.  */
 253   t->to_fetch_registers = m32r_linux_fetch_inferior_registers;
 254   t->to_store_registers = m32r_linux_store_inferior_registers;
 255
 256   /* Register the target.  */
 257   linux_nat_add_target (t);
 258 }