gdbserver/linux-bfin-low.cc

   1 /* GNU/Linux/BFIN specific low level interface, for the remote server for GDB.
   2
   3    Copyright (C) 2005-2020 Free Software Foundation, Inc.
   4
   5    Contributed by Analog Devices, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "server.h"
  23 #include "linux-low.h"
  24 #include <asm/ptrace.h>
  25
  26 /* Linux target op definitions for the BFIN architecture.  */
  27
  28 class bfin_target : public linux_process_target
  29 {
  30 public:
  31
  32   const regs_info *get_regs_info () override;
  33
  34   const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override;
  35
  36 protected:
  37
  38   void low_arch_setup () override;
  39
  40   bool low_cannot_fetch_register (int regno) override;
  41
  42   bool low_cannot_store_register (int regno) override;
  43
  44   bool low_supports_breakpoints () override;
  45
  46   CORE_ADDR low_get_pc (regcache *regcache) override;
  47
  48   void low_set_pc (regcache *regcache, CORE_ADDR newpc) override;
  49
  50   int low_decr_pc_after_break () override;
  51
  52   bool low_breakpoint_at (CORE_ADDR pc) override;
  53 };
  54
  55 /* The singleton target ops object.  */
  56
  57 static bfin_target the_bfin_target;
  58
  59 bool
  60 bfin_target::low_supports_breakpoints ()
  61 {
  62   return true;
  63 }
  64
  65 CORE_ADDR
  66 bfin_target::low_get_pc (regcache *regcache)
  67 {
  68   return linux_get_pc_32bit (regcache);
  69 }
  70
  71 void
  72 bfin_target::low_set_pc (regcache *regcache, CORE_ADDR pc)
  73 {
  74   linux_set_pc_32bit (regcache, pc);
  75 }
  76
  77 int
  78 bfin_target::low_decr_pc_after_break ()
  79 {
  80   return 2;
  81 }
  82
  83 /* Defined in auto-generated file reg-bfin.c.  */
  84 void init_registers_bfin (void);
  85 extern const struct target_desc *tdesc_bfin;
  86
  87 static int bfin_regmap[] =
  88 {
  89   PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7,
  90   PT_P0, PT_P1, PT_P2, PT_P3, PT_P4, PT_P5, PT_USP, PT_FP,
  91   PT_I0, PT_I1, PT_I2, PT_I3, PT_M0, PT_M1, PT_M2, PT_M3,
  92   PT_B0, PT_B1, PT_B2, PT_B3, PT_L0, PT_L1, PT_L2, PT_L3,
  93   PT_A0X, PT_A0W, PT_A1X, PT_A1W, PT_ASTAT, PT_RETS,
  94   PT_LC0, PT_LT0, PT_LB0, PT_LC1, PT_LT1, PT_LB1,
  95   -1 /* PT_CYCLES */, -1 /* PT_CYCLES2 */,
  96   -1 /* PT_USP */, PT_SEQSTAT, PT_SYSCFG, PT_PC, PT_RETX, PT_RETN, PT_RETE,
  97   PT_PC,
  98 };
  99
 100 #define bfin_num_regs ARRAY_SIZE (bfin_regmap)
 101
 102 bool
 103 bfin_target::low_cannot_store_register (int regno)
 104 {
 105   return (regno >= bfin_num_regs);
 106 }
 107
 108 bool
 109 bfin_target::low_cannot_fetch_register (int regno)
 110 {
 111   return (regno >= bfin_num_regs);
 112 }
 113
 114 #define bfin_breakpoint_len 2
 115 static const gdb_byte bfin_breakpoint[bfin_breakpoint_len] = {0xa1, 0x00};
 116
 117 /* Implementation of target ops method "sw_breakpoint_from_kind".  */
 118
 119 const gdb_byte *
 120 bfin_target::sw_breakpoint_from_kind (int kind, int *size)
 121 {
 122   *size = bfin_breakpoint_len;
 123   return bfin_breakpoint;
 124 }
 125
 126 bool
 127 bfin_target::low_breakpoint_at (CORE_ADDR where)
 128 {
 129   unsigned char insn[bfin_breakpoint_len];
 130
 131   read_inferior_memory(where, insn, bfin_breakpoint_len);
 132   if (insn[0] == bfin_breakpoint[0]
 133       && insn[1] == bfin_breakpoint[1])
 134     return true;
 135
 136   /* If necessary, recognize more trap instructions here.  GDB only uses the
 137      one.  */
 138   return false;
 139 }
 140
 141 void
 142 bfin_target::low_arch_setup ()
 143 {
 144   current_process ()->tdesc = tdesc_bfin;
 145 }
 146
 147 /* Support for hardware single step.  */
 148
 149 static int
 150 bfin_supports_hardware_single_step (void)
 151 {
 152   return 1;
 153 }
 154
 155 static struct usrregs_info bfin_usrregs_info =
 156   {
 157     bfin_num_regs,
 158     bfin_regmap,
 159   };
 160
 161 static struct regs_info myregs_info =
 162   {
 163     NULL, /* regset_bitmap */
 164     &bfin_usrregs_info,
 165   };
 166
 167 const regs_info *
 168 bfin_target::get_regs_info ()
 169 {
 170   return &myregs_info;
 171 }
 172
 173 struct linux_target_ops the_low_target = {
 174   NULL, /* collect_ptrace_register */
 175   NULL, /* supply_ptrace_register */
 176   NULL, /* siginfo_fixup */
 177   NULL, /* new_process */
 178   NULL, /* delete_process */
 179   NULL, /* new_thread */
 180   NULL, /* delete_thread */
 181   NULL, /* new_fork */
 182   NULL, /* prepare_to_resume */
 183   NULL, /* process_qsupported */
 184   NULL, /* supports_tracepoints */
 185   NULL, /* get_thread_area */
 186   NULL, /* install_fast_tracepoint_jump_pad */
 187   NULL, /* emit_ops */
 188   NULL, /* get_min_fast_tracepoint_insn_len */
 189   NULL, /* supports_range_stepping */
 190   bfin_supports_hardware_single_step,
 191 };
 192
 193 /* The linux target ops object.  */
 194
 195 linux_process_target *the_linux_target = &the_bfin_target;
 196
 197 void
 198 initialize_low_arch (void)
 199 {
 200   init_registers_bfin ();
 201 }