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