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 protected:
  35
  36   void low_arch_setup () override;
  37
  38   bool low_cannot_fetch_register (int regno) override;
  39
  40   bool low_cannot_store_register (int regno) override;
  41
  42   bool low_supports_breakpoints () override;
  43
  44   CORE_ADDR low_get_pc (regcache *regcache) override;
  45
  46   void low_set_pc (regcache *regcache, CORE_ADDR newpc) override;
  47 };
  48
  49 /* The singleton target ops object.  */
  50
  51 static bfin_target the_bfin_target;
  52
  53 bool
  54 bfin_target::low_supports_breakpoints ()
  55 {
  56   return true;
  57 }
  58
  59 CORE_ADDR
  60 bfin_target::low_get_pc (regcache *regcache)
  61 {
  62   return linux_get_pc_32bit (regcache);
  63 }
  64
  65 void
  66 bfin_target::low_set_pc (regcache *regcache, CORE_ADDR pc)
  67 {
  68   linux_set_pc_32bit (regcache, pc);
  69 }
  70
  71 /* Defined in auto-generated file reg-bfin.c.  */
  72 void init_registers_bfin (void);
  73 extern const struct target_desc *tdesc_bfin;
  74
  75 static int bfin_regmap[] =
  76 {
  77   PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7,
  78   PT_P0, PT_P1, PT_P2, PT_P3, PT_P4, PT_P5, PT_USP, PT_FP,
  79   PT_I0, PT_I1, PT_I2, PT_I3, PT_M0, PT_M1, PT_M2, PT_M3,
  80   PT_B0, PT_B1, PT_B2, PT_B3, PT_L0, PT_L1, PT_L2, PT_L3,
  81   PT_A0X, PT_A0W, PT_A1X, PT_A1W, PT_ASTAT, PT_RETS,
  82   PT_LC0, PT_LT0, PT_LB0, PT_LC1, PT_LT1, PT_LB1,
  83   -1 /* PT_CYCLES */, -1 /* PT_CYCLES2 */,
  84   -1 /* PT_USP */, PT_SEQSTAT, PT_SYSCFG, PT_PC, PT_RETX, PT_RETN, PT_RETE,
  85   PT_PC,
  86 };
  87
  88 #define bfin_num_regs ARRAY_SIZE (bfin_regmap)
  89
  90 bool
  91 bfin_target::low_cannot_store_register (int regno)
  92 {
  93   return (regno >= bfin_num_regs);
  94 }
  95
  96 bool
  97 bfin_target::low_cannot_fetch_register (int regno)
  98 {
  99   return (regno >= bfin_num_regs);
 100 }
 101
 102 #define bfin_breakpoint_len 2
 103 static const gdb_byte bfin_breakpoint[bfin_breakpoint_len] = {0xa1, 0x00};
 104
 105 /* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
 106
 107 static const gdb_byte *
 108 bfin_sw_breakpoint_from_kind (int kind, int *size)
 109 {
 110   *size = bfin_breakpoint_len;
 111   return bfin_breakpoint;
 112 }
 113
 114 static int
 115 bfin_breakpoint_at (CORE_ADDR where)
 116 {
 117   unsigned char insn[bfin_breakpoint_len];
 118
 119   read_inferior_memory(where, insn, bfin_breakpoint_len);
 120   if (insn[0] == bfin_breakpoint[0]
 121       && insn[1] == bfin_breakpoint[1])
 122     return 1;
 123
 124   /* If necessary, recognize more trap instructions here.  GDB only uses the
 125      one.  */
 126   return 0;
 127 }
 128
 129 void
 130 bfin_target::low_arch_setup ()
 131 {
 132   current_process ()->tdesc = tdesc_bfin;
 133 }
 134
 135 /* Support for hardware single step.  */
 136
 137 static int
 138 bfin_supports_hardware_single_step (void)
 139 {
 140   return 1;
 141 }
 142
 143 static struct usrregs_info bfin_usrregs_info =
 144   {
 145     bfin_num_regs,
 146     bfin_regmap,
 147   };
 148
 149 static struct regs_info myregs_info =
 150   {
 151     NULL, /* regset_bitmap */
 152     &bfin_usrregs_info,
 153   };
 154
 155 const regs_info *
 156 bfin_target::get_regs_info ()
 157 {
 158   return &myregs_info;
 159 }
 160
 161 struct linux_target_ops the_low_target = {
 162   NULL, /* breakpoint_kind_from_pc */
 163   bfin_sw_breakpoint_from_kind,
 164   NULL, /* get_next_pcs */
 165   2,
 166   bfin_breakpoint_at,
 167   NULL, /* supports_z_point_type */
 168   NULL, /* insert_point */
 169   NULL, /* remove_point */
 170   NULL, /* stopped_by_watchpoint */
 171   NULL, /* stopped_data_address */
 172   NULL, /* collect_ptrace_register */
 173   NULL, /* supply_ptrace_register */
 174   NULL, /* siginfo_fixup */
 175   NULL, /* new_process */
 176   NULL, /* delete_process */
 177   NULL, /* new_thread */
 178   NULL, /* delete_thread */
 179   NULL, /* new_fork */
 180   NULL, /* prepare_to_resume */
 181   NULL, /* process_qsupported */
 182   NULL, /* supports_tracepoints */
 183   NULL, /* get_thread_area */
 184   NULL, /* install_fast_tracepoint_jump_pad */
 185   NULL, /* emit_ops */
 186   NULL, /* get_min_fast_tracepoint_insn_len */
 187   NULL, /* supports_range_stepping */
 188   NULL, /* breakpoint_kind_from_current_state */
 189   bfin_supports_hardware_single_step,
 190 };
 191
 192 /* The linux target ops object.  */
 193
 194 linux_process_target *the_linux_target = &the_bfin_target;
 195
 196 void
 197 initialize_low_arch (void)
 198 {
 199   init_registers_bfin ();
 200 }