| 1 | /* GNU/Linux/Xtensa specific low level interface, for the remote server for GDB. |
| 2 | Copyright (C) 2007-2015 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 | |
| 20 | #include "server.h" |
| 21 | #include "linux-low.h" |
| 22 | |
| 23 | /* Defined in auto-generated file reg-xtensa.c. */ |
| 24 | void init_registers_xtensa (void); |
| 25 | extern const struct target_desc *tdesc_xtensa; |
| 26 | |
| 27 | #include <asm/ptrace.h> |
| 28 | #include <xtensa-config.h> |
| 29 | #include "arch/xtensa.h" |
| 30 | #include "gdb_proc_service.h" |
| 31 | |
| 32 | #include "xtensa-xtregs.c" |
| 33 | |
| 34 | enum regnum { |
| 35 | R_PC=0, R_PS, |
| 36 | R_LBEG, R_LEND, R_LCOUNT, |
| 37 | R_SAR, |
| 38 | R_WS, R_WB, |
| 39 | R_A0 = 64 |
| 40 | }; |
| 41 | |
| 42 | static void |
| 43 | xtensa_fill_gregset (struct regcache *regcache, void *buf) |
| 44 | { |
| 45 | elf_greg_t* rset = (elf_greg_t*)buf; |
| 46 | const struct target_desc *tdesc = regcache->tdesc; |
| 47 | int ar0_regnum; |
| 48 | char *ptr; |
| 49 | int i; |
| 50 | |
| 51 | /* Take care of AR registers. */ |
| 52 | |
| 53 | ar0_regnum = find_regno (tdesc, "ar0"); |
| 54 | ptr = (char*)&rset[R_A0]; |
| 55 | |
| 56 | for (i = ar0_regnum; i < ar0_regnum + XCHAL_NUM_AREGS; i++) |
| 57 | { |
| 58 | collect_register (regcache, i, ptr); |
| 59 | ptr += register_size (tdesc, i); |
| 60 | } |
| 61 | |
| 62 | /* Loop registers, if hardware has it. */ |
| 63 | |
| 64 | #if XCHAL_HAVE_LOOPS |
| 65 | collect_register_by_name (regcache, "lbeg", (char*)&rset[R_LBEG]); |
| 66 | collect_register_by_name (regcache, "lend", (char*)&rset[R_LEND]); |
| 67 | collect_register_by_name (regcache, "lcount", (char*)&rset[R_LCOUNT]); |
| 68 | #endif |
| 69 | |
| 70 | collect_register_by_name (regcache, "sar", (char*)&rset[R_SAR]); |
| 71 | collect_register_by_name (regcache, "pc", (char*)&rset[R_PC]); |
| 72 | collect_register_by_name (regcache, "ps", (char*)&rset[R_PS]); |
| 73 | collect_register_by_name (regcache, "windowbase", (char*)&rset[R_WB]); |
| 74 | collect_register_by_name (regcache, "windowstart", (char*)&rset[R_WS]); |
| 75 | } |
| 76 | |
| 77 | static void |
| 78 | xtensa_store_gregset (struct regcache *regcache, const void *buf) |
| 79 | { |
| 80 | const elf_greg_t* rset = (const elf_greg_t*)buf; |
| 81 | const struct target_desc *tdesc = regcache->tdesc; |
| 82 | int ar0_regnum; |
| 83 | char *ptr; |
| 84 | int i; |
| 85 | |
| 86 | /* Take care of AR registers. */ |
| 87 | |
| 88 | ar0_regnum = find_regno (tdesc, "ar0"); |
| 89 | ptr = (char *)&rset[R_A0]; |
| 90 | |
| 91 | for (i = ar0_regnum; i < ar0_regnum + XCHAL_NUM_AREGS; i++) |
| 92 | { |
| 93 | supply_register (regcache, i, ptr); |
| 94 | ptr += register_size (tdesc, i); |
| 95 | } |
| 96 | |
| 97 | /* Loop registers, if hardware has it. */ |
| 98 | |
| 99 | #if XCHAL_HAVE_LOOPS |
| 100 | supply_register_by_name (regcache, "lbeg", (char*)&rset[R_LBEG]); |
| 101 | supply_register_by_name (regcache, "lend", (char*)&rset[R_LEND]); |
| 102 | supply_register_by_name (regcache, "lcount", (char*)&rset[R_LCOUNT]); |
| 103 | #endif |
| 104 | |
| 105 | supply_register_by_name (regcache, "sar", (char*)&rset[R_SAR]); |
| 106 | supply_register_by_name (regcache, "pc", (char*)&rset[R_PC]); |
| 107 | supply_register_by_name (regcache, "ps", (char*)&rset[R_PS]); |
| 108 | supply_register_by_name (regcache, "windowbase", (char*)&rset[R_WB]); |
| 109 | supply_register_by_name (regcache, "windowstart", (char*)&rset[R_WS]); |
| 110 | } |
| 111 | |
| 112 | /* Xtensa GNU/Linux PTRACE interface includes extended register set. */ |
| 113 | |
| 114 | static void |
| 115 | xtensa_fill_xtregset (struct regcache *regcache, void *buf) |
| 116 | { |
| 117 | const xtensa_regtable_t *ptr; |
| 118 | |
| 119 | for (ptr = xtensa_regmap_table; ptr->name; ptr++) |
| 120 | { |
| 121 | collect_register_by_name (regcache, ptr->name, |
| 122 | (char*)buf + ptr->ptrace_offset); |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | static void |
| 127 | xtensa_store_xtregset (struct regcache *regcache, const void *buf) |
| 128 | { |
| 129 | const xtensa_regtable_t *ptr; |
| 130 | |
| 131 | for (ptr = xtensa_regmap_table; ptr->name; ptr++) |
| 132 | { |
| 133 | supply_register_by_name (regcache, ptr->name, |
| 134 | (char*)buf + ptr->ptrace_offset); |
| 135 | } |
| 136 | } |
| 137 | |
| 138 | static struct regset_info xtensa_regsets[] = { |
| 139 | { PTRACE_GETREGS, PTRACE_SETREGS, 0, sizeof (elf_gregset_t), |
| 140 | GENERAL_REGS, |
| 141 | xtensa_fill_gregset, xtensa_store_gregset }, |
| 142 | { PTRACE_GETXTREGS, PTRACE_SETXTREGS, 0, XTENSA_ELF_XTREG_SIZE, |
| 143 | EXTENDED_REGS, |
| 144 | xtensa_fill_xtregset, xtensa_store_xtregset }, |
| 145 | NULL_REGSET |
| 146 | }; |
| 147 | |
| 148 | #if XCHAL_HAVE_BE |
| 149 | #define XTENSA_BREAKPOINT {0xd2,0x0f} |
| 150 | #else |
| 151 | #define XTENSA_BREAKPOINT {0x2d,0xf0} |
| 152 | #endif |
| 153 | |
| 154 | static const gdb_byte xtensa_breakpoint[] = XTENSA_BREAKPOINT; |
| 155 | #define xtensa_breakpoint_len 2 |
| 156 | |
| 157 | /* Implementation of linux_target_ops method "sw_breakpoint_from_kind". */ |
| 158 | |
| 159 | static const gdb_byte * |
| 160 | xtensa_sw_breakpoint_from_kind (int kind, int *size) |
| 161 | { |
| 162 | *size = xtensa_breakpoint_len; |
| 163 | return xtensa_breakpoint; |
| 164 | } |
| 165 | |
| 166 | static CORE_ADDR |
| 167 | xtensa_get_pc (struct regcache *regcache) |
| 168 | { |
| 169 | unsigned long pc; |
| 170 | |
| 171 | collect_register_by_name (regcache, "pc", &pc); |
| 172 | return pc; |
| 173 | } |
| 174 | |
| 175 | static void |
| 176 | xtensa_set_pc (struct regcache *regcache, CORE_ADDR pc) |
| 177 | { |
| 178 | unsigned long newpc = pc; |
| 179 | supply_register_by_name (regcache, "pc", &newpc); |
| 180 | } |
| 181 | |
| 182 | static int |
| 183 | xtensa_breakpoint_at (CORE_ADDR where) |
| 184 | { |
| 185 | unsigned long insn; |
| 186 | |
| 187 | (*the_target->read_memory) (where, (unsigned char *) &insn, |
| 188 | xtensa_breakpoint_len); |
| 189 | return memcmp((char *) &insn, |
| 190 | xtensa_breakpoint, xtensa_breakpoint_len) == 0; |
| 191 | } |
| 192 | |
| 193 | /* Called by libthread_db. */ |
| 194 | |
| 195 | ps_err_e |
| 196 | ps_get_thread_area (const struct ps_prochandle *ph, |
| 197 | lwpid_t lwpid, int idx, void **base) |
| 198 | { |
| 199 | xtensa_elf_gregset_t regs; |
| 200 | |
| 201 | if (ptrace (PTRACE_GETREGS, lwpid, NULL, ®s) != 0) |
| 202 | return PS_ERR; |
| 203 | |
| 204 | /* IDX is the bias from the thread pointer to the beginning of the |
| 205 | thread descriptor. It has to be subtracted due to implementation |
| 206 | quirks in libthread_db. */ |
| 207 | *base = (void *) ((char *) regs.threadptr - idx); |
| 208 | |
| 209 | return PS_OK; |
| 210 | } |
| 211 | |
| 212 | static struct regsets_info xtensa_regsets_info = |
| 213 | { |
| 214 | xtensa_regsets, /* regsets */ |
| 215 | 0, /* num_regsets */ |
| 216 | NULL, /* disabled_regsets */ |
| 217 | }; |
| 218 | |
| 219 | static struct regs_info regs_info = |
| 220 | { |
| 221 | NULL, /* regset_bitmap */ |
| 222 | NULL, /* usrregs */ |
| 223 | &xtensa_regsets_info |
| 224 | }; |
| 225 | |
| 226 | static void |
| 227 | xtensa_arch_setup (void) |
| 228 | { |
| 229 | current_process ()->tdesc = tdesc_xtensa; |
| 230 | } |
| 231 | |
| 232 | static const struct regs_info * |
| 233 | xtensa_regs_info (void) |
| 234 | { |
| 235 | return ®s_info; |
| 236 | } |
| 237 | |
| 238 | struct linux_target_ops the_low_target = { |
| 239 | xtensa_arch_setup, |
| 240 | xtensa_regs_info, |
| 241 | 0, |
| 242 | 0, |
| 243 | NULL, /* fetch_register */ |
| 244 | xtensa_get_pc, |
| 245 | xtensa_set_pc, |
| 246 | NULL, /* breakpoint_kind_from_pc */ |
| 247 | xtensa_sw_breakpoint_from_kind, |
| 248 | NULL, |
| 249 | 0, |
| 250 | xtensa_breakpoint_at, |
| 251 | }; |
| 252 | |
| 253 | |
| 254 | void |
| 255 | initialize_low_arch (void) |
| 256 | { |
| 257 | /* Initialize the Linux target descriptions. */ |
| 258 | init_registers_xtensa (); |
| 259 | |
| 260 | initialize_regsets_info (&xtensa_regsets_info); |
| 261 | } |