gdb/m32r-linux-nat.c

   1 /* Native-dependent code for GNU/Linux m32r.
   2
   3    Copyright (C) 2004, 2005, 2006, 2007 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 2 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, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 #include "defs.h"
  23 #include "inferior.h"
  24 #include "gdbcore.h"
  25 #include "regcache.h"
  26 #include "linux-nat.h"
  27 #include "target.h"
  28
  29 #include "gdb_assert.h"
  30 #include "gdb_string.h"
  31 #include <sys/ptrace.h>
  32 #include <sys/user.h>
  33 #include <sys/procfs.h>
  34
  35 /* Prototypes for supply_gregset etc.  */
  36 #include "gregset.h"
  37
  38 #include "m32r-tdep.h"
  39 \f
  40
  41
  42
  43 /* Since EVB register is not available for native debug, we reduce
  44    the number of registers.  */
  45 #define M32R_LINUX_NUM_REGS (M32R_NUM_REGS - 1)
  46
  47 /* Mapping between the general-purpose registers in `struct user'
  48    format and GDB's register array layout.  */
  49 static int regmap[] = {
  50   4, 5, 6, 7, 0, 1, 2, 8,
  51   9, 10, 11, 12, 13, 24, 25, 23,
  52   19, 19, 26, 23, 22, 20, 16, 15
  53 };
  54
  55 #define PSW_REGMAP 19
  56 #define BBPSW_REGMAP 21
  57 #define SPU_REGMAP 23
  58 #define SPI_REGMAP 26
  59
  60 /* Doee apply to the corresponding SET requests as well.  */
  61 #define GETREGS_SUPPLIES(regno) (0 <= (regno) && (regno) <= M32R_LINUX_NUM_REGS)
  62 \f
  63
  64
  65 /* Transfering the general-purpose registers between GDB, inferiors
  66    and core files.  */
  67
  68 /* Fill GDB's register array with the general-purpose register values
  69    in *GREGSETP.  */
  70
  71 void
  72 supply_gregset (elf_gregset_t * gregsetp)
  73 {
  74   elf_greg_t *regp = (elf_greg_t *) gregsetp;
  75   int i;
  76   unsigned long psw, bbpsw;
  77
  78   psw = *(regp + PSW_REGMAP);
  79   bbpsw = *(regp + BBPSW_REGMAP);
  80
  81   for (i = 0; i < M32R_LINUX_NUM_REGS; i++)
  82     {
  83       elf_greg_t regval;
  84
  85       switch (i)
  86         {
  87         case PSW_REGNUM:
  88           regval = ((0x00c1 & bbpsw) << 8) | ((0xc100 & psw) >> 8);
  89           break;
  90         case CBR_REGNUM:
  91           regval = ((psw >> 8) & 1);
  92           break;
  93         default:
  94           regval = *(regp + regmap[i]);
  95           break;
  96         }
  97
  98       if (i != M32R_SP_REGNUM)
  99         regcache_raw_supply (current_regcache, i, &regval);
 100       else if (psw & 0x8000)
 101         regcache_raw_supply (current_regcache, i, regp + SPU_REGMAP);
 102       else
 103         regcache_raw_supply (current_regcache, i, regp + SPI_REGMAP);
 104     }
 105 }
 106
 107 /* Fetch all general-purpose registers from process/thread TID and
 108    store their values in GDB's register array.  */
 109
 110 static void
 111 fetch_regs (int tid)
 112 {
 113   elf_gregset_t regs;
 114
 115   if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
 116     perror_with_name (_("Couldn't get registers"));
 117
 118   supply_gregset (&regs);
 119 }
 120
 121 /* Fill register REGNO (if it is a general-purpose register) in
 122    *GREGSETPS with the value in GDB's register array.  If REGNO is -1,
 123    do this for all registers.  */
 124
 125 void
 126 fill_gregset (elf_gregset_t * gregsetp, int regno)
 127 {
 128   elf_greg_t *regp = (elf_greg_t *) gregsetp;
 129   int i;
 130   unsigned long psw, bbpsw, tmp;
 131
 132   psw = *(regp + PSW_REGMAP);
 133   bbpsw = *(regp + BBPSW_REGMAP);
 134
 135   for (i = 0; i < M32R_LINUX_NUM_REGS; i++)
 136     {
 137       if (regno != -1 && regno != i)
 138         continue;
 139
 140       if (i == CBR_REGNUM || i == PSW_REGNUM)
 141         continue;
 142
 143       if (i == SPU_REGNUM || i == SPI_REGNUM)
 144         continue;
 145
 146       if (i != M32R_SP_REGNUM)
 147         regcache_raw_collect (current_regcache, i, regp + regmap[i]);
 148       else if (psw & 0x8000)
 149         regcache_raw_collect (current_regcache, i, regp + SPU_REGMAP);
 150       else
 151         regcache_raw_collect (current_regcache, i, regp + SPI_REGMAP);
 152     }
 153 }
 154
 155 /* Store all valid general-purpose registers in GDB's register array
 156    into the process/thread specified by TID.  */
 157
 158 static void
 159 store_regs (int tid, int regno)
 160 {
 161   elf_gregset_t regs;
 162
 163   if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
 164     perror_with_name (_("Couldn't get registers"));
 165
 166   fill_gregset (&regs, regno);
 167
 168   if (ptrace (PTRACE_SETREGS, tid, 0, (int) &regs) < 0)
 169     perror_with_name (_("Couldn't write registers"));
 170 }
 171 \f
 172
 173
 174 /* Transfering floating-point registers between GDB, inferiors and cores.
 175    Since M32R has no floating-point registers, these functions do nothing.  */
 176
 177 void
 178 supply_fpregset (gdb_fpregset_t *fpregs)
 179 {
 180 }
 181
 182 void
 183 fill_fpregset (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 (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 (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 (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 (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 }