1 /* Motorola m68k native support for GNU/Linux.
3 Copyright (C) 1996-2018 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
27 #include "linux-nat.h"
29 #include "m68k-tdep.h"
33 #include "nat/gdb_ptrace.h"
35 #include <sys/ioctl.h>
37 #include <sys/procfs.h>
46 #include "floatformat.h"
48 /* Prototypes for supply_gregset etc. */
51 /* Defines ps_err_e, struct ps_prochandle. */
52 #include "gdb_proc_service.h"
54 #include "inf-ptrace.h"
56 #ifndef PTRACE_GET_THREAD_AREA
57 #define PTRACE_GET_THREAD_AREA 25
61 class m68k_linux_nat_target final
: public linux_nat_target
64 /* Add our register access methods. */
65 void fetch_registers (struct regcache
*, int) override
;
66 void store_registers (struct regcache
*, int) override
;
69 static m68k_linux_nat_target the_m68k_linux_nat_target
;
71 /* This table must line up with gdbarch_register_name in "m68k-tdep.c". */
72 static const int regmap
[] =
74 PT_D0
, PT_D1
, PT_D2
, PT_D3
, PT_D4
, PT_D5
, PT_D6
, PT_D7
,
75 PT_A0
, PT_A1
, PT_A2
, PT_A3
, PT_A4
, PT_A5
, PT_A6
, PT_USP
,
77 /* PT_FP0, ..., PT_FP7 */
78 21, 24, 27, 30, 33, 36, 39, 42,
79 /* PT_FPCR, PT_FPSR, PT_FPIAR */
83 /* Which ptrace request retrieves which registers?
84 These apply to the corresponding SET requests as well. */
85 #define NUM_GREGS (18)
86 #define MAX_NUM_REGS (NUM_GREGS + 11)
89 getregs_supplies (int regno
)
91 return 0 <= regno
&& regno
< NUM_GREGS
;
95 getfpregs_supplies (int regno
)
97 return M68K_FP0_REGNUM
<= regno
&& regno
<= M68K_FPI_REGNUM
;
100 /* Does the current host support the GETREGS request? */
101 static int have_ptrace_getregs
=
102 #ifdef HAVE_PTRACE_GETREGS
111 /* Fetching registers directly from the U area, one at a time. */
113 /* Fetch one register. */
116 fetch_register (struct regcache
*regcache
, int regno
)
118 struct gdbarch
*gdbarch
= regcache
->arch ();
121 gdb_byte buf
[M68K_MAX_REGISTER_SIZE
];
122 pid_t tid
= get_ptrace_pid (regcache_get_ptid (regcache
));
124 regaddr
= 4 * regmap
[regno
];
125 for (i
= 0; i
< register_size (gdbarch
, regno
); i
+= sizeof (long))
128 val
= ptrace (PTRACE_PEEKUSER
, tid
, regaddr
, 0);
129 memcpy (&buf
[i
], &val
, sizeof (long));
130 regaddr
+= sizeof (long);
132 error (_("Couldn't read register %s (#%d): %s."),
133 gdbarch_register_name (gdbarch
, regno
),
134 regno
, safe_strerror (errno
));
136 regcache_raw_supply (regcache
, regno
, buf
);
139 /* Fetch register values from the inferior.
140 If REGNO is negative, do this for all registers.
141 Otherwise, REGNO specifies which register (so we can save time). */
144 old_fetch_inferior_registers (struct regcache
*regcache
, int regno
)
148 fetch_register (regcache
, regno
);
153 regno
< gdbarch_num_regs (regcache
->arch ());
156 fetch_register (regcache
, regno
);
161 /* Store one register. */
164 store_register (const struct regcache
*regcache
, int regno
)
166 struct gdbarch
*gdbarch
= regcache
->arch ();
169 gdb_byte buf
[M68K_MAX_REGISTER_SIZE
];
170 pid_t tid
= get_ptrace_pid (regcache_get_ptid (regcache
));
172 regaddr
= 4 * regmap
[regno
];
174 /* Put the contents of regno into a local buffer. */
175 regcache_raw_collect (regcache
, regno
, buf
);
177 /* Store the local buffer into the inferior a chunk at the time. */
178 for (i
= 0; i
< register_size (gdbarch
, regno
); i
+= sizeof (long))
181 memcpy (&val
, &buf
[i
], sizeof (long));
182 ptrace (PTRACE_POKEUSER
, tid
, regaddr
, val
);
183 regaddr
+= sizeof (long);
185 error (_("Couldn't write register %s (#%d): %s."),
186 gdbarch_register_name (gdbarch
, regno
),
187 regno
, safe_strerror (errno
));
191 /* Store our register values back into the inferior.
192 If REGNO is negative, do this for all registers.
193 Otherwise, REGNO specifies which register (so we can save time). */
196 old_store_inferior_registers (const struct regcache
*regcache
, int regno
)
200 store_register (regcache
, regno
);
205 regno
< gdbarch_num_regs (regcache
->arch ());
208 store_register (regcache
, regno
);
213 /* Given a pointer to a general register set in /proc format
214 (elf_gregset_t *), unpack the register contents and supply
215 them as gdb's idea of the current register values. */
218 supply_gregset (struct regcache
*regcache
, const elf_gregset_t
*gregsetp
)
220 struct gdbarch
*gdbarch
= regcache
->arch ();
221 const elf_greg_t
*regp
= (const elf_greg_t
*) gregsetp
;
224 for (regi
= M68K_D0_REGNUM
;
225 regi
<= gdbarch_sp_regnum (gdbarch
);
227 regcache_raw_supply (regcache
, regi
, ®p
[regmap
[regi
]]);
228 regcache_raw_supply (regcache
, gdbarch_ps_regnum (gdbarch
),
230 regcache_raw_supply (regcache
,
231 gdbarch_pc_regnum (gdbarch
), ®p
[PT_PC
]);
234 /* Fill register REGNO (if it is a general-purpose register) in
235 *GREGSETPS with the value in GDB's register array. If REGNO is -1,
236 do this for all registers. */
238 fill_gregset (const struct regcache
*regcache
,
239 elf_gregset_t
*gregsetp
, int regno
)
241 elf_greg_t
*regp
= (elf_greg_t
*) gregsetp
;
244 for (i
= 0; i
< NUM_GREGS
; i
++)
245 if (regno
== -1 || regno
== i
)
246 regcache_raw_collect (regcache
, i
, regp
+ regmap
[i
]);
249 #ifdef HAVE_PTRACE_GETREGS
251 /* Fetch all general-purpose registers from process/thread TID and
252 store their values in GDB's register array. */
255 fetch_regs (struct regcache
*regcache
, int tid
)
259 if (ptrace (PTRACE_GETREGS
, tid
, 0, (int) ®s
) < 0)
263 /* The kernel we're running on doesn't support the GETREGS
264 request. Reset `have_ptrace_getregs'. */
265 have_ptrace_getregs
= 0;
269 perror_with_name (_("Couldn't get registers"));
272 supply_gregset (regcache
, (const elf_gregset_t
*) ®s
);
275 /* Store all valid general-purpose registers in GDB's register array
276 into the process/thread specified by TID. */
279 store_regs (const struct regcache
*regcache
, int tid
, int regno
)
283 if (ptrace (PTRACE_GETREGS
, tid
, 0, (int) ®s
) < 0)
284 perror_with_name (_("Couldn't get registers"));
286 fill_gregset (regcache
, ®s
, regno
);
288 if (ptrace (PTRACE_SETREGS
, tid
, 0, (int) ®s
) < 0)
289 perror_with_name (_("Couldn't write registers"));
294 static void fetch_regs (struct regcache
*regcache
, int tid
)
298 static void store_regs (const struct regcache
*regcache
, int tid
, int regno
)
305 /* Transfering floating-point registers between GDB, inferiors and cores. */
307 /* What is the address of fpN within the floating-point register set F? */
308 #define FPREG_ADDR(f, n) (&(f)->fpregs[(n) * 3])
310 /* Fill GDB's register array with the floating-point register values in
314 supply_fpregset (struct regcache
*regcache
, const elf_fpregset_t
*fpregsetp
)
316 struct gdbarch
*gdbarch
= regcache
->arch ();
319 for (regi
= gdbarch_fp0_regnum (gdbarch
);
320 regi
< gdbarch_fp0_regnum (gdbarch
) + 8; regi
++)
321 regcache_raw_supply (regcache
, regi
,
322 FPREG_ADDR (fpregsetp
,
323 regi
- gdbarch_fp0_regnum (gdbarch
)));
324 regcache_raw_supply (regcache
, M68K_FPC_REGNUM
, &fpregsetp
->fpcntl
[0]);
325 regcache_raw_supply (regcache
, M68K_FPS_REGNUM
, &fpregsetp
->fpcntl
[1]);
326 regcache_raw_supply (regcache
, M68K_FPI_REGNUM
, &fpregsetp
->fpcntl
[2]);
329 /* Fill register REGNO (if it is a floating-point register) in
330 *FPREGSETP with the value in GDB's register array. If REGNO is -1,
331 do this for all registers. */
334 fill_fpregset (const struct regcache
*regcache
,
335 elf_fpregset_t
*fpregsetp
, int regno
)
337 struct gdbarch
*gdbarch
= regcache
->arch ();
340 /* Fill in the floating-point registers. */
341 for (i
= gdbarch_fp0_regnum (gdbarch
);
342 i
< gdbarch_fp0_regnum (gdbarch
) + 8; i
++)
343 if (regno
== -1 || regno
== i
)
344 regcache_raw_collect (regcache
, i
,
345 FPREG_ADDR (fpregsetp
,
346 i
- gdbarch_fp0_regnum (gdbarch
)));
348 /* Fill in the floating-point control registers. */
349 for (i
= M68K_FPC_REGNUM
; i
<= M68K_FPI_REGNUM
; i
++)
350 if (regno
== -1 || regno
== i
)
351 regcache_raw_collect (regcache
, i
,
352 &fpregsetp
->fpcntl
[i
- M68K_FPC_REGNUM
]);
355 #ifdef HAVE_PTRACE_GETREGS
357 /* Fetch all floating-point registers from process/thread TID and store
358 thier values in GDB's register array. */
361 fetch_fpregs (struct regcache
*regcache
, int tid
)
363 elf_fpregset_t fpregs
;
365 if (ptrace (PTRACE_GETFPREGS
, tid
, 0, (int) &fpregs
) < 0)
366 perror_with_name (_("Couldn't get floating point status"));
368 supply_fpregset (regcache
, (const elf_fpregset_t
*) &fpregs
);
371 /* Store all valid floating-point registers in GDB's register array
372 into the process/thread specified by TID. */
375 store_fpregs (const struct regcache
*regcache
, int tid
, int regno
)
377 elf_fpregset_t fpregs
;
379 if (ptrace (PTRACE_GETFPREGS
, tid
, 0, (int) &fpregs
) < 0)
380 perror_with_name (_("Couldn't get floating point status"));
382 fill_fpregset (regcache
, &fpregs
, regno
);
384 if (ptrace (PTRACE_SETFPREGS
, tid
, 0, (int) &fpregs
) < 0)
385 perror_with_name (_("Couldn't write floating point status"));
390 static void fetch_fpregs (struct regcache
*regcache
, int tid
)
394 static void store_fpregs (const struct regcache
*regcache
, int tid
, int regno
)
400 /* Transferring arbitrary registers between GDB and inferior. */
402 /* Fetch register REGNO from the child process. If REGNO is -1, do
403 this for all registers (including the floating point and SSE
407 m68k_linux_nat_target::fetch_registers (struct regcache
*regcache
, int regno
)
411 /* Use the old method of peeking around in `struct user' if the
412 GETREGS request isn't available. */
413 if (! have_ptrace_getregs
)
415 old_fetch_inferior_registers (regcache
, regno
);
419 tid
= get_ptrace_pid (regcache_get_ptid (regcache
));
421 /* Use the PTRACE_GETFPXREGS request whenever possible, since it
422 transfers more registers in one system call, and we'll cache the
423 results. But remember that fetch_fpxregs can fail, and return
427 fetch_regs (regcache
, tid
);
429 /* The call above might reset `have_ptrace_getregs'. */
430 if (! have_ptrace_getregs
)
432 old_fetch_inferior_registers (regcache
, -1);
436 fetch_fpregs (regcache
, tid
);
440 if (getregs_supplies (regno
))
442 fetch_regs (regcache
, tid
);
446 if (getfpregs_supplies (regno
))
448 fetch_fpregs (regcache
, tid
);
452 internal_error (__FILE__
, __LINE__
,
453 _("Got request for bad register number %d."), regno
);
456 /* Store register REGNO back into the child process. If REGNO is -1,
457 do this for all registers (including the floating point and SSE
460 m68k_linux_nat_target::store_registers (struct regcache
*regcache
, int regno
)
464 /* Use the old method of poking around in `struct user' if the
465 SETREGS request isn't available. */
466 if (! have_ptrace_getregs
)
468 old_store_inferior_registers (regcache
, regno
);
472 tid
= get_ptrace_pid (regcache_get_ptid (regcache
));
474 /* Use the PTRACE_SETFPREGS requests whenever possible, since it
475 transfers more registers in one system call. But remember that
476 store_fpregs can fail, and return zero. */
479 store_regs (regcache
, tid
, regno
);
480 store_fpregs (regcache
, tid
, regno
);
484 if (getregs_supplies (regno
))
486 store_regs (regcache
, tid
, regno
);
490 if (getfpregs_supplies (regno
))
492 store_fpregs (regcache
, tid
, regno
);
496 internal_error (__FILE__
, __LINE__
,
497 _("Got request to store bad register number %d."), regno
);
501 /* Fetch the thread-local storage pointer for libthread_db. */
504 ps_get_thread_area (struct ps_prochandle
*ph
,
505 lwpid_t lwpid
, int idx
, void **base
)
507 if (ptrace (PTRACE_GET_THREAD_AREA
, lwpid
, NULL
, base
) < 0)
510 /* IDX is the bias from the thread pointer to the beginning of the
511 thread descriptor. It has to be subtracted due to implementation
512 quirks in libthread_db. */
513 *base
= (char *) *base
- idx
;
519 _initialize_m68k_linux_nat (void)
521 /* Register the target. */
522 linux_target
= &the_m68k_linux_nat_target
;
523 add_inf_child_target (&the_m68k_linux_nat_target
);