gdb/xtensa-linux-nat.c

   1 /* Xtensa GNU/Linux native support.
   2
   3    Copyright (C) 2007-2017 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 "frame.h"
  22 #include "inferior.h"
  23 #include "gdbcore.h"
  24 #include "regcache.h"
  25 #include "target.h"
  26 #include "linux-nat.h"
  27 #include <sys/types.h>
  28 #include <signal.h>
  29 #include <sys/user.h>
  30 #include <sys/ioctl.h>
  31 #include "gdb_wait.h"
  32 #include <fcntl.h>
  33 #include <sys/procfs.h>
  34 #include "nat/gdb_ptrace.h"
  35 #include <asm/ptrace.h>
  36
  37 #include "gregset.h"
  38 #include "xtensa-tdep.h"
  39
  40 /* Defines ps_err_e, struct ps_prochandle.  */
  41 #include "gdb_proc_service.h"
  42
  43 /* Extended register set depends on hardware configs.
  44    Keeping these definitions separately allows to introduce
  45    hardware-specific overlays.  */
  46 #include "xtensa-xtregs.c"
  47
  48 void
  49 fill_gregset (const struct regcache *regcache,
  50               gdb_gregset_t *gregsetp, int regnum)
  51 {
  52   int i;
  53   xtensa_elf_gregset_t *regs = (xtensa_elf_gregset_t *) gregsetp;
  54   struct gdbarch *gdbarch = get_regcache_arch (regcache);
  55
  56   if (regnum == gdbarch_pc_regnum (gdbarch) || regnum == -1)
  57     regcache_raw_collect (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
  58   if (regnum == gdbarch_ps_regnum (gdbarch) || regnum == -1)
  59     regcache_raw_collect (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);
  60
  61   if (regnum == gdbarch_tdep (gdbarch)->wb_regnum || regnum == -1)
  62     regcache_raw_collect (regcache,
  63                           gdbarch_tdep (gdbarch)->wb_regnum,
  64                           &regs->windowbase);
  65   if (regnum == gdbarch_tdep (gdbarch)->ws_regnum || regnum == -1)
  66     regcache_raw_collect (regcache,
  67                           gdbarch_tdep (gdbarch)->ws_regnum,
  68                           &regs->windowstart);
  69   if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum || regnum == -1)
  70     regcache_raw_collect (regcache,
  71                           gdbarch_tdep (gdbarch)->lbeg_regnum,
  72                           &regs->lbeg);
  73   if (regnum == gdbarch_tdep (gdbarch)->lend_regnum || regnum == -1)
  74     regcache_raw_collect (regcache,
  75                           gdbarch_tdep (gdbarch)->lend_regnum,
  76                           &regs->lend);
  77   if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum || regnum == -1)
  78     regcache_raw_collect (regcache,
  79                           gdbarch_tdep (gdbarch)->lcount_regnum,
  80                           &regs->lcount);
  81   if (regnum == gdbarch_tdep (gdbarch)->sar_regnum || regnum == -1)
  82     regcache_raw_collect (regcache,
  83                           gdbarch_tdep (gdbarch)->sar_regnum,
  84                           &regs->sar);
  85   if (regnum >=gdbarch_tdep (gdbarch)->ar_base
  86       && regnum < gdbarch_tdep (gdbarch)->ar_base
  87                     + gdbarch_tdep (gdbarch)->num_aregs)
  88     regcache_raw_collect (regcache,regnum,
  89                           &regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
  90   else if (regnum == -1)
  91     {
  92       for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
  93         regcache_raw_collect (regcache,
  94                               gdbarch_tdep (gdbarch)->ar_base + i,
  95                               &regs->ar[i]);
  96     }
  97   if (regnum >= gdbarch_tdep (gdbarch)->a0_base
  98       && regnum < gdbarch_tdep (gdbarch)->a0_base + C0_NREGS)
  99     regcache_raw_collect (regcache, regnum,
 100                           &regs->ar[(4 * regs->windowbase + regnum
 101                                      - gdbarch_tdep (gdbarch)->a0_base)
 102                           % gdbarch_tdep (gdbarch)->num_aregs]);
 103   else if (regnum == -1)
 104     {
 105       for (i = 0; i < C0_NREGS; ++i)
 106         regcache_raw_collect (regcache,
 107                               gdbarch_tdep (gdbarch)->a0_base + i,
 108                               &regs->ar[(4 * regs->windowbase + i)
 109                               % gdbarch_tdep (gdbarch)->num_aregs]);
 110     }
 111 }
 112
 113 static void
 114 supply_gregset_reg (struct regcache *regcache,
 115                     const gdb_gregset_t *gregsetp, int regnum)
 116 {
 117   int i;
 118   xtensa_elf_gregset_t *regs = (xtensa_elf_gregset_t *) gregsetp;
 119
 120   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 121
 122   if (regnum == gdbarch_pc_regnum (gdbarch) || regnum == -1)
 123     regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
 124   if (regnum == gdbarch_ps_regnum (gdbarch) || regnum == -1)
 125     regcache_raw_supply (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);
 126
 127   if (regnum == gdbarch_tdep (gdbarch)->wb_regnum || regnum == -1)
 128     regcache_raw_supply (regcache,
 129                           gdbarch_tdep (gdbarch)->wb_regnum,
 130                           &regs->windowbase);
 131   if (regnum == gdbarch_tdep (gdbarch)->ws_regnum || regnum == -1)
 132     regcache_raw_supply (regcache,
 133                           gdbarch_tdep (gdbarch)->ws_regnum,
 134                           &regs->windowstart);
 135   if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum || regnum == -1)
 136     regcache_raw_supply (regcache,
 137                           gdbarch_tdep (gdbarch)->lbeg_regnum,
 138                           &regs->lbeg);
 139   if (regnum == gdbarch_tdep (gdbarch)->lend_regnum || regnum == -1)
 140     regcache_raw_supply (regcache,
 141                           gdbarch_tdep (gdbarch)->lend_regnum,
 142                           &regs->lend);
 143   if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum || regnum == -1)
 144     regcache_raw_supply (regcache,
 145                           gdbarch_tdep (gdbarch)->lcount_regnum,
 146                           &regs->lcount);
 147   if (regnum == gdbarch_tdep (gdbarch)->sar_regnum || regnum == -1)
 148     regcache_raw_supply (regcache,
 149                           gdbarch_tdep (gdbarch)->sar_regnum,
 150                           &regs->sar);
 151   if (regnum >=gdbarch_tdep (gdbarch)->ar_base
 152       && regnum < gdbarch_tdep (gdbarch)->ar_base
 153                     + gdbarch_tdep (gdbarch)->num_aregs)
 154     regcache_raw_supply (regcache,regnum,
 155                           &regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
 156   else if (regnum == -1)
 157     {
 158       for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
 159         regcache_raw_supply (regcache,
 160                               gdbarch_tdep (gdbarch)->ar_base + i,
 161                               &regs->ar[i]);
 162     }
 163   if (regnum >= gdbarch_tdep (gdbarch)->a0_base
 164       && regnum < gdbarch_tdep (gdbarch)->a0_base + C0_NREGS)
 165     regcache_raw_supply (regcache, regnum,
 166                          &regs->ar[(4 * regs->windowbase + regnum
 167                                     - gdbarch_tdep (gdbarch)->a0_base)
 168                          % gdbarch_tdep (gdbarch)->num_aregs]);
 169   else if (regnum == -1)
 170     {
 171       for (i = 0; i < C0_NREGS; ++i)
 172         regcache_raw_supply (regcache,
 173                              gdbarch_tdep (gdbarch)->a0_base + i,
 174                              &regs->ar[(4 * regs->windowbase + i)
 175                              % gdbarch_tdep (gdbarch)->num_aregs]);
 176     }
 177 }
 178
 179 void
 180 supply_gregset (struct regcache *regcache, const gdb_gregset_t *gregsetp)
 181 {
 182   supply_gregset_reg (regcache, gregsetp, -1);
 183 }
 184
 185 void
 186 fill_fpregset (const struct regcache *regcache,
 187                gdb_fpregset_t *fpregsetp, int regnum)
 188 {
 189   return;
 190 }
 191
 192 void
 193 supply_fpregset (struct regcache *regcache,
 194                  const gdb_fpregset_t *fpregsetp)
 195 {
 196   return;
 197 }
 198
 199 /* Fetch greg-register(s) from process/thread TID
 200    and store value(s) in GDB's register array.  */
 201
 202 static void
 203 fetch_gregs (struct regcache *regcache, int regnum)
 204 {
 205   int tid = ptid_get_lwp (regcache_get_ptid (regcache));
 206   gdb_gregset_t regs;
 207   int areg;
 208
 209   if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
 210     {
 211       perror_with_name (_("Couldn't get registers"));
 212       return;
 213     }
 214
 215   supply_gregset_reg (regcache, &regs, regnum);
 216 }
 217
 218 /* Store greg-register(s) in GDB's register
 219    array into the process/thread specified by TID.  */
 220
 221 static void
 222 store_gregs (struct regcache *regcache, int regnum)
 223 {
 224   int tid = ptid_get_lwp (regcache_get_ptid (regcache));
 225   gdb_gregset_t regs;
 226   int areg;
 227
 228   if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
 229     {
 230       perror_with_name (_("Couldn't get registers"));
 231       return;
 232     }
 233
 234   fill_gregset (regcache, &regs, regnum);
 235
 236   if (ptrace (PTRACE_SETREGS, tid, 0, (long) &regs) < 0)
 237     {
 238       perror_with_name (_("Couldn't write registers"));
 239       return;
 240     }
 241 }
 242
 243 static int xtreg_lo;
 244 static int xtreg_high;
 245
 246 /* Fetch/Store Xtensa TIE registers.  Xtensa GNU/Linux PTRACE
 247    interface provides special requests for this.  */
 248
 249 static void
 250 fetch_xtregs (struct regcache *regcache, int regnum)
 251 {
 252   int tid = ptid_get_lwp (regcache_get_ptid (regcache));
 253   const xtensa_regtable_t *ptr;
 254   char xtregs [XTENSA_ELF_XTREG_SIZE];
 255
 256   if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
 257     perror_with_name (_("Couldn't get extended registers"));
 258
 259   for (ptr = xtensa_regmap_table; ptr->name; ptr++)
 260     if (regnum == ptr->gdb_regnum || regnum == -1)
 261       regcache_raw_supply (regcache, ptr->gdb_regnum,
 262                            xtregs + ptr->ptrace_offset);
 263 }
 264
 265 static void
 266 store_xtregs (struct regcache *regcache, int regnum)
 267 {
 268   int tid = ptid_get_lwp (regcache_get_ptid (regcache));
 269   const xtensa_regtable_t *ptr;
 270   char xtregs [XTENSA_ELF_XTREG_SIZE];
 271
 272   if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
 273     perror_with_name (_("Couldn't get extended registers"));
 274
 275   for (ptr = xtensa_regmap_table; ptr->name; ptr++)
 276     if (regnum == ptr->gdb_regnum || regnum == -1)
 277       regcache_raw_collect (regcache, ptr->gdb_regnum,
 278                             xtregs + ptr->ptrace_offset);
 279
 280   if (ptrace (PTRACE_SETXTREGS, tid, 0, (long)&xtregs) < 0)
 281     perror_with_name (_("Couldn't write extended registers"));
 282 }
 283
 284 static void
 285 xtensa_linux_fetch_inferior_registers (struct target_ops *ops,
 286                                        struct regcache *regcache, int regnum)
 287 {
 288   if (regnum == -1)
 289     {
 290       fetch_gregs (regcache, regnum);
 291       fetch_xtregs (regcache, regnum);
 292     }
 293   else if ((regnum < xtreg_lo) || (regnum > xtreg_high))
 294     fetch_gregs (regcache, regnum);
 295   else
 296     fetch_xtregs (regcache, regnum);
 297 }
 298
 299 static void
 300 xtensa_linux_store_inferior_registers (struct target_ops *ops,
 301                                        struct regcache *regcache, int regnum)
 302 {
 303   if (regnum == -1)
 304     {
 305       store_gregs (regcache, regnum);
 306       store_xtregs (regcache, regnum);
 307     }
 308   else if ((regnum < xtreg_lo) || (regnum > xtreg_high))
 309     store_gregs (regcache, regnum);
 310   else
 311     store_xtregs (regcache, regnum);
 312 }
 313
 314 /* Called by libthread_db.  */
 315
 316 ps_err_e
 317 ps_get_thread_area (struct ps_prochandle *ph,
 318                     lwpid_t lwpid, int idx, void **base)
 319 {
 320   xtensa_elf_gregset_t regs;
 321
 322   if (ptrace (PTRACE_GETREGS, lwpid, NULL, &regs) != 0)
 323     return PS_ERR;
 324
 325   /* IDX is the bias from the thread pointer to the beginning of the
 326      thread descriptor.  It has to be subtracted due to implementation
 327      quirks in libthread_db.  */
 328   *base = (void *) ((char *) regs.threadptr - idx);
 329
 330   return PS_OK;
 331 }
 332
 333 void _initialize_xtensa_linux_nat (void);
 334
 335 void
 336 _initialize_xtensa_linux_nat (void)
 337 {
 338   struct target_ops *t;
 339   const xtensa_regtable_t *ptr;
 340
 341   /* Calculate the number range for extended registers.  */
 342   xtreg_lo = 1000000000;
 343   xtreg_high = -1;
 344   for (ptr = xtensa_regmap_table; ptr->name; ptr++)
 345     {
 346       if (ptr->gdb_regnum < xtreg_lo)
 347         xtreg_lo = ptr->gdb_regnum;
 348       if (ptr->gdb_regnum > xtreg_high)
 349         xtreg_high = ptr->gdb_regnum;
 350     }
 351
 352   /* Fill in the generic GNU/Linux methods.  */
 353   t = linux_target ();
 354
 355   /* Add our register access methods.  */
 356   t->to_fetch_registers = xtensa_linux_fetch_inferior_registers;
 357   t->to_store_registers = xtensa_linux_store_inferior_registers;
 358
 359   linux_nat_add_target (t);
 360 }