gdb/gdbserver/linux-s390-low.c

   1 /* GNU/Linux S/390 specific low level interface, for the remote server
   2    for GDB.
   3    Copyright (C) 2001, 2002, 2005, 2006, 2007, 2008
   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 3 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, see <http://www.gnu.org/licenses/>.  */
  20
  21 /* This file is used for both 31-bit and 64-bit S/390 systems.  */
  22
  23 #include "server.h"
  24 #include "linux-low.h"
  25
  26 #include <asm/ptrace.h>
  27
  28 /* Defined in auto-generated file reg-s390.c.  */
  29 void init_registers_s390 (void);
  30 /* Defined in auto-generated file reg-s390x.c.  */
  31 void init_registers_s390x (void);
  32
  33
  34 #define s390_num_regs 51
  35
  36 static int s390_regmap[] = {
  37   PT_PSWMASK, PT_PSWADDR,
  38
  39   PT_GPR0, PT_GPR1, PT_GPR2, PT_GPR3,
  40   PT_GPR4, PT_GPR5, PT_GPR6, PT_GPR7,
  41   PT_GPR8, PT_GPR9, PT_GPR10, PT_GPR11,
  42   PT_GPR12, PT_GPR13, PT_GPR14, PT_GPR15,
  43
  44   PT_ACR0, PT_ACR1, PT_ACR2, PT_ACR3,
  45   PT_ACR4, PT_ACR5, PT_ACR6, PT_ACR7,
  46   PT_ACR8, PT_ACR9, PT_ACR10, PT_ACR11,
  47   PT_ACR12, PT_ACR13, PT_ACR14, PT_ACR15,
  48
  49   PT_FPC,
  50
  51 #ifndef __s390x__
  52   PT_FPR0_HI, PT_FPR1_HI, PT_FPR2_HI, PT_FPR3_HI,
  53   PT_FPR4_HI, PT_FPR5_HI, PT_FPR6_HI, PT_FPR7_HI,
  54   PT_FPR8_HI, PT_FPR9_HI, PT_FPR10_HI, PT_FPR11_HI,
  55   PT_FPR12_HI, PT_FPR13_HI, PT_FPR14_HI, PT_FPR15_HI,
  56 #else
  57   PT_FPR0, PT_FPR1, PT_FPR2, PT_FPR3,
  58   PT_FPR4, PT_FPR5, PT_FPR6, PT_FPR7,
  59   PT_FPR8, PT_FPR9, PT_FPR10, PT_FPR11,
  60   PT_FPR12, PT_FPR13, PT_FPR14, PT_FPR15,
  61 #endif
  62 };
  63
  64 static int
  65 s390_cannot_fetch_register (int regno)
  66 {
  67   if (s390_regmap[regno] == -1)
  68     return 1;
  69
  70   return 0;
  71 }
  72
  73 static int
  74 s390_cannot_store_register (int regno)
  75 {
  76   if (s390_regmap[regno] == -1)
  77     return 1;
  78
  79   return 0;
  80 }
  81
  82 static void
  83 s390_collect_ptrace_register (int regno, char *buf)
  84 {
  85   int size = register_size (regno);
  86   if (size < sizeof (long))
  87     {
  88       memset (buf, 0, sizeof (long));
  89
  90       if (regno == find_regno ("pswa")
  91           || (regno >= find_regno ("r0") && regno <= find_regno ("r15")))
  92         collect_register (regno, buf + sizeof (long) - size);
  93       else
  94         collect_register (regno, buf);
  95
  96       /* When debugging a 32-bit inferior on a 64-bit host, make sure
  97          the 31-bit addressing mode bit is set in the PSW mask.  */
  98       if (regno == find_regno ("pswm"))
  99         buf[size] |= 0x80;
 100     }
 101   else
 102     collect_register (regno, buf);
 103 }
 104
 105 static void
 106 s390_supply_ptrace_register (int regno, const char *buf)
 107 {
 108   int size = register_size (regno);
 109   if (size < sizeof (long))
 110     {
 111       if (regno == find_regno ("pswa")
 112           || (regno >= find_regno ("r0") && regno <= find_regno ("r15")))
 113         supply_register (regno, buf + sizeof (long) - size);
 114       else
 115         supply_register (regno, buf);
 116     }
 117   else
 118     supply_register (regno, buf);
 119 }
 120
 121 /* Provide only a fill function for the general register set.  ps_lgetregs
 122    will use this for NPTL support.  */
 123
 124 static void s390_fill_gregset (void *buf)
 125 {
 126   int i;
 127
 128   for (i = 0; i < 34; i++)
 129     s390_collect_ptrace_register (i, (char *) buf + s390_regmap[i]);
 130 }
 131
 132 struct regset_info target_regsets[] = {
 133   { 0, 0, 0, GENERAL_REGS, s390_fill_gregset, NULL },
 134   { 0, 0, -1, -1, NULL, NULL }
 135 };
 136
 137
 138 static const unsigned char s390_breakpoint[] = { 0, 1 };
 139 #define s390_breakpoint_len 2
 140
 141 static CORE_ADDR
 142 s390_get_pc ()
 143 {
 144   if (register_size (0) == 4)
 145     {
 146       unsigned int pc;
 147       collect_register_by_name ("pswa", &pc);
 148 #ifndef __s390x__
 149       pc &= 0x7fffffff;
 150 #endif
 151       return pc;
 152     }
 153   else
 154     {
 155       unsigned long pc;
 156       collect_register_by_name ("pswa", &pc);
 157       return pc;
 158     }
 159 }
 160
 161 static void
 162 s390_set_pc (CORE_ADDR newpc)
 163 {
 164   if (register_size (0) == 4)
 165     {
 166       unsigned int pc = newpc;
 167 #ifndef __s390x__
 168       pc |= 0x80000000;
 169 #endif
 170       supply_register_by_name ("pswa", &pc);
 171     }
 172   else
 173     {
 174       unsigned long pc = newpc;
 175       supply_register_by_name ("pswa", &pc);
 176     }
 177 }
 178
 179
 180 static void
 181 s390_arch_setup (void)
 182 {
 183   /* Assume 31-bit inferior process.  */
 184   init_registers_s390 ();
 185
 186   /* On a 64-bit host, check the low bit of the (31-bit) PSWM
 187      -- if this is one, we actually have a 64-bit inferior.  */
 188 #ifdef __s390x__
 189   {
 190     unsigned int pswm;
 191     collect_register_by_name ("pswm", &pswm);
 192     if (pswm & 1)
 193       init_registers_s390x ();
 194   }
 195 #endif
 196 }
 197
 198
 199 static int
 200 s390_breakpoint_at (CORE_ADDR pc)
 201 {
 202   unsigned char c[s390_breakpoint_len];
 203   read_inferior_memory (pc, c, s390_breakpoint_len);
 204   return memcmp (c, s390_breakpoint, s390_breakpoint_len) == 0;
 205 }
 206
 207
 208 struct linux_target_ops the_low_target = {
 209   s390_arch_setup,
 210   s390_num_regs,
 211   s390_regmap,
 212   s390_cannot_fetch_register,
 213   s390_cannot_store_register,
 214   s390_get_pc,
 215   s390_set_pc,
 216   s390_breakpoint,
 217   s390_breakpoint_len,
 218   NULL,
 219   s390_breakpoint_len,
 220   s390_breakpoint_at,
 221   NULL,
 222   NULL,
 223   NULL,
 224   NULL,
 225   s390_collect_ptrace_register,
 226   s390_supply_ptrace_register,
 227 };
 228