gdb/gdbserver/linux-sh-low.c

   1 /* GNU/Linux/SH specific low level interface, for the remote server for GDB.
   2    Copyright (C) 1995-2015 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include "server.h"
  20 #include "linux-low.h"
  21
  22 /* Defined in auto-generated file reg-sh.c.  */
  23 void init_registers_sh (void);
  24 extern const struct target_desc *tdesc_sh;
  25
  26 #ifdef HAVE_SYS_REG_H
  27 #include <sys/reg.h>
  28 #endif
  29
  30 #include <asm/ptrace.h>
  31
  32 #define sh_num_regs 41
  33
  34 /* Currently, don't check/send MQ.  */
  35 static int sh_regmap[] = {
  36  0,     4,      8,      12,     16,     20,     24,     28,
  37  32,    36,     40,     44,     48,     52,     56,     60,
  38
  39  REG_PC*4,   REG_PR*4,   REG_GBR*4,  -1,
  40  REG_MACH*4, REG_MACL*4, REG_SR*4,
  41  REG_FPUL*4, REG_FPSCR*4,
  42
  43  REG_FPREG0*4+0,   REG_FPREG0*4+4,   REG_FPREG0*4+8,   REG_FPREG0*4+12,
  44  REG_FPREG0*4+16,  REG_FPREG0*4+20,  REG_FPREG0*4+24,  REG_FPREG0*4+28,
  45  REG_FPREG0*4+32,  REG_FPREG0*4+36,  REG_FPREG0*4+40,  REG_FPREG0*4+44,
  46  REG_FPREG0*4+48,  REG_FPREG0*4+52,  REG_FPREG0*4+56,  REG_FPREG0*4+60,
  47 };
  48
  49 static int
  50 sh_cannot_store_register (int regno)
  51 {
  52   return 0;
  53 }
  54
  55 static int
  56 sh_cannot_fetch_register (int regno)
  57 {
  58   return 0;
  59 }
  60
  61 static CORE_ADDR
  62 sh_get_pc (struct regcache *regcache)
  63 {
  64   unsigned long pc;
  65   collect_register_by_name (regcache, "pc", &pc);
  66   return pc;
  67 }
  68
  69 static void
  70 sh_set_pc (struct regcache *regcache, CORE_ADDR pc)
  71 {
  72   unsigned long newpc = pc;
  73   supply_register_by_name (regcache, "pc", &newpc);
  74 }
  75
  76 /* Correct in either endianness, obviously.  */
  77 static const unsigned short sh_breakpoint = 0xc3c3;
  78 #define sh_breakpoint_len 2
  79
  80 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
  81
  82 static const gdb_byte *
  83 sh_sw_breakpoint_from_kind (int kind, int *size)
  84 {
  85   *size = sh_breakpoint_len;
  86   return (const gdb_byte *) &sh_breakpoint;
  87 }
  88
  89 static int
  90 sh_breakpoint_at (CORE_ADDR where)
  91 {
  92   unsigned short insn;
  93
  94   (*the_target->read_memory) (where, (unsigned char *) &insn, 2);
  95   if (insn == sh_breakpoint)
  96     return 1;
  97
  98   /* If necessary, recognize more trap instructions here.  GDB only uses the
  99      one.  */
 100   return 0;
 101 }
 102
 103 /* Provide only a fill function for the general register set.  ps_lgetregs
 104    will use this for NPTL support.  */
 105
 106 static void sh_fill_gregset (struct regcache *regcache, void *buf)
 107 {
 108   int i;
 109
 110   for (i = 0; i < 23; i++)
 111     if (sh_regmap[i] != -1)
 112       collect_register (regcache, i, (char *) buf + sh_regmap[i]);
 113 }
 114
 115 static struct regset_info sh_regsets[] = {
 116   { 0, 0, 0, 0, GENERAL_REGS, sh_fill_gregset, NULL },
 117   { 0, 0, 0, -1, -1, NULL, NULL }
 118 };
 119
 120 static struct regsets_info sh_regsets_info =
 121   {
 122     sh_regsets, /* regsets */
 123     0, /* num_regsets */
 124     NULL, /* disabled_regsets */
 125   };
 126
 127 static struct usrregs_info sh_usrregs_info =
 128   {
 129     sh_num_regs,
 130     sh_regmap,
 131   };
 132
 133 static struct regs_info regs_info =
 134   {
 135     NULL, /* regset_bitmap */
 136     &sh_usrregs_info,
 137     &sh_regsets_info
 138   };
 139
 140 static const struct regs_info *
 141 sh_regs_info (void)
 142 {
 143   return &regs_info;
 144 }
 145
 146 static void
 147 sh_arch_setup (void)
 148 {
 149   current_process ()->tdesc = tdesc_sh;
 150 }
 151
 152 struct linux_target_ops the_low_target = {
 153   sh_arch_setup,
 154   sh_regs_info,
 155   sh_cannot_fetch_register,
 156   sh_cannot_store_register,
 157   NULL, /* fetch_register */
 158   sh_get_pc,
 159   sh_set_pc,
 160   NULL, /* breakpoint_kind_from_pc */
 161   sh_sw_breakpoint_from_kind,
 162   NULL,
 163   0,
 164   sh_breakpoint_at,
 165 };
 166
 167 void
 168 initialize_low_arch (void)
 169 {
 170   init_registers_sh ();
 171
 172   initialize_regsets_info (&sh_regsets_info);
 173 }