1 /* Native-dependent code for GNU/Linux m32r. 2 3 Copyright (C) 2004-2019 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 19 20 #include "defs.h" 21 #include "inferior.h" 22 #include "gdbcore.h" 23 #include "regcache.h" 24 #include "linux-nat.h" 25 #include "target.h" 26 #include "nat/gdb_ptrace.h" 27 #include <sys/user.h> 28 #include <sys/procfs.h> 29 #include "inf-ptrace.h" 30 31 /* Prototypes for supply_gregset etc. */ 32 #include "gregset.h" 33 34 #include "m32r-tdep.h" 35 36 37 class m32r_linux_nat_target final : public linux_nat_target 38 { 39 public: 40 /* Add our register access methods. */ 41 void fetch_registers (struct regcache *, int) override; 42 void store_registers (struct regcache *, int) override; 43 }; 44 45 static m32r_linux_nat_target the_m32r_linux_nat_target; 46 47 /* Since EVB register is not available for native debug, we reduce 48 the number of registers. */ 49 #define M32R_LINUX_NUM_REGS (M32R_NUM_REGS - 1) 50 51 /* Mapping between the general-purpose registers in `struct user' 52 format and GDB's register array layout. */ 53 static int regmap[] = { 54 4, 5, 6, 7, 0, 1, 2, 8, 55 9, 10, 11, 12, 13, 24, 25, 23, 56 19, 19, 26, 23, 22, 20, 16, 15 57 }; 58 59 #define PSW_REGMAP 19 60 #define BBPSW_REGMAP 21 61 #define SPU_REGMAP 23 62 #define SPI_REGMAP 26 63 64 /* Doee (??) apply to the corresponding SET requests as well. */ 65 #define GETREGS_SUPPLIES(regno) (0 <= (regno) \ 66 && (regno) <= M32R_LINUX_NUM_REGS) 67 68 69 70 /* Transfering the general-purpose registers between GDB, inferiors 71 and core files. */ 72 73 /* Fill GDB's register array with the general-purpose register values 74 in *GREGSETP. */ 75 76 void 77 supply_gregset (struct regcache *regcache, const elf_gregset_t * gregsetp) 78 { 79 const elf_greg_t *regp = (const elf_greg_t *) gregsetp; 80 int i; 81 unsigned long psw, bbpsw; 82 83 psw = *(regp + PSW_REGMAP); 84 bbpsw = *(regp + BBPSW_REGMAP); 85 86 for (i = 0; i < M32R_LINUX_NUM_REGS; i++) 87 { 88 elf_greg_t regval; 89 90 switch (i) 91 { 92 case PSW_REGNUM: 93 regval = ((0x00c1 & bbpsw) << 8) | ((0xc100 & psw) >> 8); 94 break; 95 case CBR_REGNUM: 96 regval = ((psw >> 8) & 1); 97 break; 98 default: 99 regval = *(regp + regmap[i]); 100 break; 101 } 102 103 if (i != M32R_SP_REGNUM) 104 regcache->raw_supply (i, ®val); 105 else if (psw & 0x8000) 106 regcache->raw_supply (i, regp + SPU_REGMAP); 107 else 108 regcache->raw_supply (i, regp + SPI_REGMAP); 109 } 110 } 111 112 /* Fetch all general-purpose registers from process/thread TID and 113 store their values in GDB's register array. */ 114 115 static void 116 fetch_regs (struct regcache *regcache, int tid) 117 { 118 elf_gregset_t regs; 119 120 if (ptrace (PTRACE_GETREGS, tid, 0, (int) ®s) < 0) 121 perror_with_name (_("Couldn't get registers")); 122 123 supply_gregset (regcache, (const elf_gregset_t *) ®s); 124 } 125 126 /* Fill register REGNO (if it is a general-purpose register) in 127 *GREGSETPS with the value in GDB's register array. If REGNO is -1, 128 do this for all registers. */ 129 130 void 131 fill_gregset (const struct regcache *regcache, 132 elf_gregset_t * gregsetp, int regno) 133 { 134 elf_greg_t *regp = (elf_greg_t *) gregsetp; 135 int i; 136 unsigned long psw, bbpsw, tmp; 137 138 psw = *(regp + PSW_REGMAP); 139 bbpsw = *(regp + BBPSW_REGMAP); 140 141 for (i = 0; i < M32R_LINUX_NUM_REGS; i++) 142 { 143 if (regno != -1 && regno != i) 144 continue; 145 146 if (i == CBR_REGNUM || i == PSW_REGNUM) 147 continue; 148 149 if (i == SPU_REGNUM || i == SPI_REGNUM) 150 continue; 151 152 if (i != M32R_SP_REGNUM) 153 regcache->raw_collect (i, regp + regmap[i]); 154 else if (psw & 0x8000) 155 regcache->raw_collect (i, regp + SPU_REGMAP); 156 else 157 regcache->raw_collect (i, regp + SPI_REGMAP); 158 } 159 } 160 161 /* Store all valid general-purpose registers in GDB's register array 162 into the process/thread specified by TID. */ 163 164 static void 165 store_regs (const struct regcache *regcache, int tid, int regno) 166 { 167 elf_gregset_t regs; 168 169 if (ptrace (PTRACE_GETREGS, tid, 0, (int) ®s) < 0) 170 perror_with_name (_("Couldn't get registers")); 171 172 fill_gregset (regcache, ®s, regno); 173 174 if (ptrace (PTRACE_SETREGS, tid, 0, (int) ®s) < 0) 175 perror_with_name (_("Couldn't write registers")); 176 } 177 178 179 180 /* Transfering floating-point registers between GDB, inferiors and cores. 181 Since M32R has no floating-point registers, these functions do nothing. */ 182 183 void 184 supply_fpregset (struct regcache *regcache, const gdb_fpregset_t *fpregs) 185 { 186 } 187 188 void 189 fill_fpregset (const struct regcache *regcache, 190 gdb_fpregset_t *fpregs, int regno) 191 { 192 } 193 194 195 196 /* Transferring arbitrary registers between GDB and inferior. */ 197 198 /* Fetch register REGNO from the child process. If REGNO is -1, do 199 this for all registers (including the floating point and SSE 200 registers). */ 201 202 void 203 m32r_linux_nat_target::fetch_registers (struct regcache *regcache, int regno) 204 { 205 pid_t tid = get_ptrace_pid (regcache->ptid ()); 206 207 /* Use the PTRACE_GETREGS request whenever possible, since it 208 transfers more registers in one system call, and we'll cache the 209 results. */ 210 if (regno == -1 || GETREGS_SUPPLIES (regno)) 211 { 212 fetch_regs (regcache, tid); 213 return; 214 } 215 216 internal_error (__FILE__, __LINE__, 217 _("Got request for bad register number %d."), regno); 218 } 219 220 /* Store register REGNO back into the child process. If REGNO is -1, 221 do this for all registers (including the floating point and SSE 222 registers). */ 223 void 224 m32r_linux_nat_target::store_registers (struct regcache *regcache, int regno) 225 { 226 pid_t tid = get_ptrace_pid (regcache->ptid ()); 227 228 /* Use the PTRACE_SETREGS request whenever possible, since it 229 transfers more registers in one system call. */ 230 if (regno == -1 || GETREGS_SUPPLIES (regno)) 231 { 232 store_regs (regcache, tid, regno); 233 return; 234 } 235 236 internal_error (__FILE__, __LINE__, 237 _("Got request to store bad register number %d."), regno); 238 } 239 240 void 241 _initialize_m32r_linux_nat (void) 242 { 243 /* Register the target. */ 244 linux_target = &the_m32r_linux_nat_target; 245 add_inf_child_target (&the_m32r_linux_nat_target); 246 } 247