gdb/m32r-linux-nat.c

   1 /* Native-dependent code for GNU/Linux m32r.
   2
   3    Copyright 2004 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., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "inferior.h"
  24 #include "gdbcore.h"
  25 #include "regcache.h"
  26 #include "linux-nat.h"
  27
  28 #include "gdb_assert.h"
  29 #include "gdb_string.h"
  30 #include <sys/ptrace.h>
  31 #include <sys/user.h>
  32 #include <sys/procfs.h>
  33
  34 /* Prototypes for supply_gregset etc.  */
  35 #include "gregset.h"
  36
  37 #include "m32r-tdep.h"
  38 \f
  39
  40
  41
  42 /* Since EVB register is not available for native debug, we reduce
  43    the number of registers.  */
  44 #define M32R_LINUX_NUM_REGS (M32R_NUM_REGS - 1)
  45
  46 /* Mapping between the general-purpose registers in `struct user'
  47    format and GDB's register array layout.  */
  48 static int regmap[] = {
  49   4, 5, 6, 7, 0, 1, 2, 8,
  50   9, 10, 11, 12, 13, 24, 25, 23,
  51   19, 19, 26, 23, 22, 20, 16, 15
  52 };
  53
  54 #define PSW_REGMAP 19
  55 #define BBPSW_REGMAP 21
  56 #define SPU_REGMAP 23
  57 #define SPI_REGMAP 26
  58
  59 /* Doee apply to the corresponding SET requests as well.  */
  60 #define GETREGS_SUPPLIES(regno) (0 <= (regno) && (regno) <= M32R_LINUX_NUM_REGS)
  61 \f
  62
  63
  64 /* Transfering the general-purpose registers between GDB, inferiors
  65    and core files.  */
  66
  67 /* Fill GDB's register array with the general-purpose register values
  68    in *GREGSETP.  */
  69
  70 void
  71 supply_gregset (elf_gregset_t * gregsetp)
  72 {
  73   elf_greg_t *regp = (elf_greg_t *) gregsetp;
  74   int i;
  75   unsigned long psw, bbpsw;
  76
  77   psw = *(regp + PSW_REGMAP);
  78   bbpsw = *(regp + BBPSW_REGMAP);
  79
  80   for (i = 0; i < M32R_LINUX_NUM_REGS; i++)
  81     {
  82       switch (i)
  83         {
  84         case PSW_REGNUM:
  85           *(regp + regmap[i]) =
  86             ((0x00c1 & bbpsw) << 8) | ((0xc100 & psw) >> 8);
  87           break;
  88         case CBR_REGNUM:
  89           *(regp + regmap[i]) = ((psw >> 8) & 1);
  90           break;
  91         }
  92
  93       if (i != M32R_SP_REGNUM)
  94         regcache_raw_supply (current_regcache, i, regp + regmap[i]);
  95       else if (psw & 0x8000)
  96         regcache_raw_supply (current_regcache, i, regp + SPU_REGMAP);
  97       else
  98         regcache_raw_supply (current_regcache, i, regp + SPI_REGMAP);
  99     }
 100 }
 101
 102 /* Fetch all general-purpose registers from process/thread TID and
 103    store their values in GDB's register array.  */
 104
 105 static void
 106 fetch_regs (int tid)
 107 {
 108   elf_gregset_t regs;
 109
 110   if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
 111     perror_with_name (_("Couldn't get registers"));
 112
 113   supply_gregset (&regs);
 114 }
 115
 116 /* Fill register REGNO (if it is a general-purpose register) in
 117    *GREGSETPS with the value in GDB's register array.  If REGNO is -1,
 118    do this for all registers.  */
 119
 120 void
 121 fill_gregset (elf_gregset_t * gregsetp, int regno)
 122 {
 123   elf_greg_t *regp = (elf_greg_t *) gregsetp;
 124   int i;
 125   unsigned long psw, bbpsw, tmp;
 126
 127   psw = *(regp + PSW_REGMAP);
 128   bbpsw = *(regp + BBPSW_REGMAP);
 129
 130   for (i = 0; i < M32R_LINUX_NUM_REGS; i++)
 131     {
 132       if (regno != -1 && regno != i)
 133         continue;
 134
 135       if (i == CBR_REGNUM || i == PSW_REGNUM)
 136         continue;
 137
 138       if (i == SPU_REGNUM || i == SPI_REGNUM)
 139         continue;
 140
 141       if (i != M32R_SP_REGNUM)
 142         regcache_raw_collect (current_regcache, i, regp + regmap[i]);
 143       else if (psw & 0x8000)
 144         regcache_raw_collect (current_regcache, i, regp + SPU_REGMAP);
 145       else
 146         regcache_raw_collect (current_regcache, i, regp + SPI_REGMAP);
 147     }
 148 }
 149
 150 /* Store all valid general-purpose registers in GDB's register array
 151    into the process/thread specified by TID.  */
 152
 153 static void
 154 store_regs (int tid, int regno)
 155 {
 156   elf_gregset_t regs;
 157
 158   if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
 159     perror_with_name (_("Couldn't get registers"));
 160
 161   fill_gregset (&regs, regno);
 162
 163   if (ptrace (PTRACE_SETREGS, tid, 0, (int) &regs) < 0)
 164     perror_with_name (_("Couldn't write registers"));
 165 }
 166 \f
 167
 168
 169 /* Transfering floating-point registers between GDB, inferiors and cores.
 170    Since M32R has no floating-point registers, these functions do nothing.  */
 171
 172 void
 173 supply_fpregset (gdb_fpregset_t *fpregs)
 174 {
 175 }
 176
 177 void
 178 fill_fpregset (gdb_fpregset_t *fpregs, int regno)
 179 {
 180 }
 181 \f
 182
 183
 184 /* Transferring arbitrary registers between GDB and inferior.  */
 185
 186 /* Fetch register REGNO from the child process.  If REGNO is -1, do
 187    this for all registers (including the floating point and SSE
 188    registers).  */
 189
 190 void
 191 fetch_inferior_registers (int regno)
 192 {
 193   int tid;
 194
 195   /* GNU/Linux LWP ID's are process ID's.  */
 196   tid = TIDGET (inferior_ptid);
 197   if (tid == 0)
 198     tid = PIDGET (inferior_ptid);       /* Not a threaded program.  */
 199
 200   /* Use the PTRACE_GETREGS request whenever possible, since it
 201      transfers more registers in one system call, and we'll cache the
 202      results.  */
 203   if (regno == -1 || GETREGS_SUPPLIES (regno))
 204     {
 205       fetch_regs (tid);
 206       return;
 207     }
 208
 209   internal_error (__FILE__, __LINE__,
 210                   _("Got request for bad register number %d."), regno);
 211 }
 212
 213 /* Store register REGNO back into the child process.  If REGNO is -1,
 214    do this for all registers (including the floating point and SSE
 215    registers).  */
 216 void
 217 store_inferior_registers (int regno)
 218 {
 219   int tid;
 220
 221   /* GNU/Linux LWP ID's are process ID's.  */
 222   if ((tid = TIDGET (inferior_ptid)) == 0)
 223     tid = PIDGET (inferior_ptid);       /* Not a threaded program.  */
 224
 225   /* Use the PTRACE_SETREGS request whenever possible, since it
 226      transfers more registers in one system call.  */
 227   if (regno == -1 || GETREGS_SUPPLIES (regno))
 228     {
 229       store_regs (tid, regno);
 230       return;
 231     }
 232
 233   internal_error (__FILE__, __LINE__,
 234                   _("Got request to store bad register number %d."), regno);
 235 }