gdb/xtensa-linux-nat.c

   1 /* Xtensa GNU/Linux native support.
   2
   3    Copyright (C) 2007-2018 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 class xtensa_linux_nat_target final : public linux_nat_target
  49 {
  50 public:
  51   /* Add our register access methods.  */
  52   void fetch_registers (struct regcache *, int) override;
  53   void store_registers (struct regcache *, int) override;
  54 };
  55
  56 static xtensa_linux_nat_target the_xtensa_linux_nat_target;
  57
  58 void
  59 fill_gregset (const struct regcache *regcache,
  60               gdb_gregset_t *gregsetp, int regnum)
  61 {
  62   int i;
  63   xtensa_elf_gregset_t *regs = (xtensa_elf_gregset_t *) gregsetp;
  64   struct gdbarch *gdbarch = regcache->arch ();
  65
  66   if (regnum == gdbarch_pc_regnum (gdbarch) || regnum == -1)
  67     regcache_raw_collect (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
  68   if (regnum == gdbarch_ps_regnum (gdbarch) || regnum == -1)
  69     regcache_raw_collect (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);
  70
  71   if (regnum == gdbarch_tdep (gdbarch)->wb_regnum || regnum == -1)
  72     regcache_raw_collect (regcache,
  73                           gdbarch_tdep (gdbarch)->wb_regnum,
  74                           &regs->windowbase);
  75   if (regnum == gdbarch_tdep (gdbarch)->ws_regnum || regnum == -1)
  76     regcache_raw_collect (regcache,
  77                           gdbarch_tdep (gdbarch)->ws_regnum,
  78                           &regs->windowstart);
  79   if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum || regnum == -1)
  80     regcache_raw_collect (regcache,
  81                           gdbarch_tdep (gdbarch)->lbeg_regnum,
  82                           &regs->lbeg);
  83   if (regnum == gdbarch_tdep (gdbarch)->lend_regnum || regnum == -1)
  84     regcache_raw_collect (regcache,
  85                           gdbarch_tdep (gdbarch)->lend_regnum,
  86                           &regs->lend);
  87   if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum || regnum == -1)
  88     regcache_raw_collect (regcache,
  89                           gdbarch_tdep (gdbarch)->lcount_regnum,
  90                           &regs->lcount);
  91   if (regnum == gdbarch_tdep (gdbarch)->sar_regnum || regnum == -1)
  92     regcache_raw_collect (regcache,
  93                           gdbarch_tdep (gdbarch)->sar_regnum,
  94                           &regs->sar);
  95   if (regnum == gdbarch_tdep (gdbarch)->threadptr_regnum || regnum == -1)
  96     regcache_raw_collect (regcache,
  97                           gdbarch_tdep (gdbarch)->threadptr_regnum,
  98                           &regs->threadptr);
  99   if (regnum >=gdbarch_tdep (gdbarch)->ar_base
 100       && regnum < gdbarch_tdep (gdbarch)->ar_base
 101                     + gdbarch_tdep (gdbarch)->num_aregs)
 102     regcache_raw_collect (regcache,regnum,
 103                           &regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
 104   else if (regnum == -1)
 105     {
 106       for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
 107         regcache_raw_collect (regcache,
 108                               gdbarch_tdep (gdbarch)->ar_base + i,
 109                               &regs->ar[i]);
 110     }
 111   if (regnum >= gdbarch_tdep (gdbarch)->a0_base
 112       && regnum < gdbarch_tdep (gdbarch)->a0_base + C0_NREGS)
 113     regcache_raw_collect (regcache, regnum,
 114                           &regs->ar[(4 * regs->windowbase + regnum
 115                                      - gdbarch_tdep (gdbarch)->a0_base)
 116                           % gdbarch_tdep (gdbarch)->num_aregs]);
 117   else if (regnum == -1)
 118     {
 119       for (i = 0; i < C0_NREGS; ++i)
 120         regcache_raw_collect (regcache,
 121                               gdbarch_tdep (gdbarch)->a0_base + i,
 122                               &regs->ar[(4 * regs->windowbase + i)
 123                               % gdbarch_tdep (gdbarch)->num_aregs]);
 124     }
 125 }
 126
 127 static void
 128 supply_gregset_reg (struct regcache *regcache,
 129                     const gdb_gregset_t *gregsetp, int regnum)
 130 {
 131   int i;
 132   xtensa_elf_gregset_t *regs = (xtensa_elf_gregset_t *) gregsetp;
 133
 134   struct gdbarch *gdbarch = regcache->arch ();
 135
 136   if (regnum == gdbarch_pc_regnum (gdbarch) || regnum == -1)
 137     regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &regs->pc);
 138   if (regnum == gdbarch_ps_regnum (gdbarch) || regnum == -1)
 139     regcache_raw_supply (regcache, gdbarch_ps_regnum (gdbarch), &regs->ps);
 140
 141   if (regnum == gdbarch_tdep (gdbarch)->wb_regnum || regnum == -1)
 142     regcache_raw_supply (regcache,
 143                           gdbarch_tdep (gdbarch)->wb_regnum,
 144                           &regs->windowbase);
 145   if (regnum == gdbarch_tdep (gdbarch)->ws_regnum || regnum == -1)
 146     regcache_raw_supply (regcache,
 147                           gdbarch_tdep (gdbarch)->ws_regnum,
 148                           &regs->windowstart);
 149   if (regnum == gdbarch_tdep (gdbarch)->lbeg_regnum || regnum == -1)
 150     regcache_raw_supply (regcache,
 151                           gdbarch_tdep (gdbarch)->lbeg_regnum,
 152                           &regs->lbeg);
 153   if (regnum == gdbarch_tdep (gdbarch)->lend_regnum || regnum == -1)
 154     regcache_raw_supply (regcache,
 155                           gdbarch_tdep (gdbarch)->lend_regnum,
 156                           &regs->lend);
 157   if (regnum == gdbarch_tdep (gdbarch)->lcount_regnum || regnum == -1)
 158     regcache_raw_supply (regcache,
 159                           gdbarch_tdep (gdbarch)->lcount_regnum,
 160                           &regs->lcount);
 161   if (regnum == gdbarch_tdep (gdbarch)->sar_regnum || regnum == -1)
 162     regcache_raw_supply (regcache,
 163                           gdbarch_tdep (gdbarch)->sar_regnum,
 164                           &regs->sar);
 165   if (regnum == gdbarch_tdep (gdbarch)->threadptr_regnum || regnum == -1)
 166     regcache_raw_supply (regcache,
 167                           gdbarch_tdep (gdbarch)->threadptr_regnum,
 168                           &regs->threadptr);
 169   if (regnum >=gdbarch_tdep (gdbarch)->ar_base
 170       && regnum < gdbarch_tdep (gdbarch)->ar_base
 171                     + gdbarch_tdep (gdbarch)->num_aregs)
 172     regcache_raw_supply (regcache,regnum,
 173                           &regs->ar[regnum - gdbarch_tdep (gdbarch)->ar_base]);
 174   else if (regnum == -1)
 175     {
 176       for (i = 0; i < gdbarch_tdep (gdbarch)->num_aregs; ++i)
 177         regcache_raw_supply (regcache,
 178                               gdbarch_tdep (gdbarch)->ar_base + i,
 179                               &regs->ar[i]);
 180     }
 181   if (regnum >= gdbarch_tdep (gdbarch)->a0_base
 182       && regnum < gdbarch_tdep (gdbarch)->a0_base + C0_NREGS)
 183     regcache_raw_supply (regcache, regnum,
 184                          &regs->ar[(4 * regs->windowbase + regnum
 185                                     - gdbarch_tdep (gdbarch)->a0_base)
 186                          % gdbarch_tdep (gdbarch)->num_aregs]);
 187   else if (regnum == -1)
 188     {
 189       for (i = 0; i < C0_NREGS; ++i)
 190         regcache_raw_supply (regcache,
 191                              gdbarch_tdep (gdbarch)->a0_base + i,
 192                              &regs->ar[(4 * regs->windowbase + i)
 193                              % gdbarch_tdep (gdbarch)->num_aregs]);
 194     }
 195 }
 196
 197 void
 198 supply_gregset (struct regcache *regcache, const gdb_gregset_t *gregsetp)
 199 {
 200   supply_gregset_reg (regcache, gregsetp, -1);
 201 }
 202
 203 void
 204 fill_fpregset (const struct regcache *regcache,
 205                gdb_fpregset_t *fpregsetp, int regnum)
 206 {
 207   return;
 208 }
 209
 210 void
 211 supply_fpregset (struct regcache *regcache,
 212                  const gdb_fpregset_t *fpregsetp)
 213 {
 214   return;
 215 }
 216
 217 /* Fetch greg-register(s) from process/thread TID
 218    and store value(s) in GDB's register array.  */
 219
 220 static void
 221 fetch_gregs (struct regcache *regcache, int regnum)
 222 {
 223   int tid = ptid_get_lwp (regcache->ptid ());
 224   gdb_gregset_t regs;
 225   int areg;
 226
 227   if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
 228     {
 229       perror_with_name (_("Couldn't get registers"));
 230       return;
 231     }
 232
 233   supply_gregset_reg (regcache, &regs, regnum);
 234 }
 235
 236 /* Store greg-register(s) in GDB's register
 237    array into the process/thread specified by TID.  */
 238
 239 static void
 240 store_gregs (struct regcache *regcache, int regnum)
 241 {
 242   int tid = ptid_get_lwp (regcache->ptid ());
 243   gdb_gregset_t regs;
 244   int areg;
 245
 246   if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
 247     {
 248       perror_with_name (_("Couldn't get registers"));
 249       return;
 250     }
 251
 252   fill_gregset (regcache, &regs, regnum);
 253
 254   if (ptrace (PTRACE_SETREGS, tid, 0, (long) &regs) < 0)
 255     {
 256       perror_with_name (_("Couldn't write registers"));
 257       return;
 258     }
 259 }
 260
 261 static int xtreg_lo;
 262 static int xtreg_high;
 263
 264 /* Fetch/Store Xtensa TIE registers.  Xtensa GNU/Linux PTRACE
 265    interface provides special requests for this.  */
 266
 267 static void
 268 fetch_xtregs (struct regcache *regcache, int regnum)
 269 {
 270   int tid = ptid_get_lwp (regcache->ptid ());
 271   const xtensa_regtable_t *ptr;
 272   char xtregs [XTENSA_ELF_XTREG_SIZE];
 273
 274   if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
 275     perror_with_name (_("Couldn't get extended registers"));
 276
 277   for (ptr = xtensa_regmap_table; ptr->name; ptr++)
 278     if (regnum == ptr->gdb_regnum || regnum == -1)
 279       regcache_raw_supply (regcache, ptr->gdb_regnum,
 280                            xtregs + ptr->ptrace_offset);
 281 }
 282
 283 static void
 284 store_xtregs (struct regcache *regcache, int regnum)
 285 {
 286   int tid = ptid_get_lwp (regcache->ptid ());
 287   const xtensa_regtable_t *ptr;
 288   char xtregs [XTENSA_ELF_XTREG_SIZE];
 289
 290   if (ptrace (PTRACE_GETXTREGS, tid, 0, (long)&xtregs) < 0)
 291     perror_with_name (_("Couldn't get extended registers"));
 292
 293   for (ptr = xtensa_regmap_table; ptr->name; ptr++)
 294     if (regnum == ptr->gdb_regnum || regnum == -1)
 295       regcache_raw_collect (regcache, ptr->gdb_regnum,
 296                             xtregs + ptr->ptrace_offset);
 297
 298   if (ptrace (PTRACE_SETXTREGS, tid, 0, (long)&xtregs) < 0)
 299     perror_with_name (_("Couldn't write extended registers"));
 300 }
 301
 302 void
 303 xtensa_linux_nat_target::fetch_registers (struct regcache *regcache,
 304                                           int regnum)
 305 {
 306   if (regnum == -1)
 307     {
 308       fetch_gregs (regcache, regnum);
 309       fetch_xtregs (regcache, regnum);
 310     }
 311   else if ((regnum < xtreg_lo) || (regnum > xtreg_high))
 312     fetch_gregs (regcache, regnum);
 313   else
 314     fetch_xtregs (regcache, regnum);
 315 }
 316
 317 void
 318 xtensa_linux_nat_target::store_registers (struct regcache *regcache,
 319                                           int regnum)
 320 {
 321   if (regnum == -1)
 322     {
 323       store_gregs (regcache, regnum);
 324       store_xtregs (regcache, regnum);
 325     }
 326   else if ((regnum < xtreg_lo) || (regnum > xtreg_high))
 327     store_gregs (regcache, regnum);
 328   else
 329     store_xtregs (regcache, regnum);
 330 }
 331
 332 /* Called by libthread_db.  */
 333
 334 ps_err_e
 335 ps_get_thread_area (struct ps_prochandle *ph,
 336                     lwpid_t lwpid, int idx, void **base)
 337 {
 338   xtensa_elf_gregset_t regs;
 339
 340   if (ptrace (PTRACE_GETREGS, lwpid, NULL, &regs) != 0)
 341     return PS_ERR;
 342
 343   /* IDX is the bias from the thread pointer to the beginning of the
 344      thread descriptor.  It has to be subtracted due to implementation
 345      quirks in libthread_db.  */
 346   *base = (void *) ((char *) regs.threadptr - idx);
 347
 348   return PS_OK;
 349 }
 350
 351 void
 352 _initialize_xtensa_linux_nat (void)
 353 {
 354   const xtensa_regtable_t *ptr;
 355
 356   /* Calculate the number range for extended registers.  */
 357   xtreg_lo = 1000000000;
 358   xtreg_high = -1;
 359   for (ptr = xtensa_regmap_table; ptr->name; ptr++)
 360     {
 361       if (ptr->gdb_regnum < xtreg_lo)
 362         xtreg_lo = ptr->gdb_regnum;
 363       if (ptr->gdb_regnum > xtreg_high)
 364         xtreg_high = ptr->gdb_regnum;
 365     }
 366
 367   linux_target = &the_xtensa_linux_nat_target;
 368   add_inf_child_target (&the_xtensa_linux_nat_target);
 369 }