1 /* GNU/Linux on ARM native support.
2 Copyright (C) 1999-2015 Free Software Foundation, Inc.
4 This file is part of GDB.
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.
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.
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/>. */
24 #include "linux-nat.h"
25 #include "target-descriptions.h"
28 #include "gdbthread.h"
31 #include "arm-linux-tdep.h"
32 #include "aarch32-linux-nat.h"
34 #include <elf/common.h>
36 #include "nat/gdb_ptrace.h"
37 #include <sys/utsname.h>
38 #include <sys/procfs.h>
40 #include "nat/linux-ptrace.h"
42 /* Prototypes for supply_gregset etc. */
45 /* Defines ps_err_e, struct ps_prochandle. */
46 #include "gdb_proc_service.h"
48 #ifndef PTRACE_GET_THREAD_AREA
49 #define PTRACE_GET_THREAD_AREA 22
52 #ifndef PTRACE_GETWMMXREGS
53 #define PTRACE_GETWMMXREGS 18
54 #define PTRACE_SETWMMXREGS 19
57 #ifndef PTRACE_GETVFPREGS
58 #define PTRACE_GETVFPREGS 27
59 #define PTRACE_SETVFPREGS 28
62 #ifndef PTRACE_GETHBPREGS
63 #define PTRACE_GETHBPREGS 29
64 #define PTRACE_SETHBPREGS 30
67 extern int arm_apcs_32;
69 /* On GNU/Linux, threads are implemented as pseudo-processes, in which
70 case we may be tracing more than one process at a time. In that
71 case, inferior_ptid will contain the main process ID and the
72 individual thread (process) ID. get_thread_id () is used to get
73 the thread id if it's available, and the process id otherwise. */
76 get_thread_id (ptid_t ptid)
78 int tid = ptid_get_lwp (ptid);
80 tid = ptid_get_pid (ptid);
84 #define GET_THREAD_ID(PTID) get_thread_id (PTID)
86 /* Get the whole floating point state of the process and store it
90 fetch_fpregs (struct regcache *regcache)
93 gdb_byte fp[ARM_LINUX_SIZEOF_NWFPE];
95 /* Get the thread id for the ptrace call. */
96 tid = GET_THREAD_ID (inferior_ptid);
98 /* Read the floating point state. */
99 if (have_ptrace_getregset == TRIBOOL_TRUE)
104 iov.iov_len = ARM_LINUX_SIZEOF_NWFPE;
106 ret = ptrace (PTRACE_GETREGSET, tid, NT_FPREGSET, &iov);
109 ret = ptrace (PT_GETFPREGS, tid, 0, fp);
113 warning (_("Unable to fetch the floating point registers."));
118 regcache_raw_supply (regcache, ARM_FPS_REGNUM,
119 fp + NWFPE_FPSR_OFFSET);
121 /* Fetch the floating point registers. */
122 for (regno = ARM_F0_REGNUM; regno <= ARM_F7_REGNUM; regno++)
123 supply_nwfpe_register (regcache, regno, fp);
126 /* Save the whole floating point state of the process using
127 the contents from regcache. */
130 store_fpregs (const struct regcache *regcache)
133 gdb_byte fp[ARM_LINUX_SIZEOF_NWFPE];
135 /* Get the thread id for the ptrace call. */
136 tid = GET_THREAD_ID (inferior_ptid);
138 /* Read the floating point state. */
139 if (have_ptrace_getregset == TRIBOOL_TRUE)
141 elf_fpregset_t fpregs;
144 iov.iov_base = &fpregs;
145 iov.iov_len = sizeof (fpregs);
147 ret = ptrace (PTRACE_GETREGSET, tid, NT_FPREGSET, &iov);
150 ret = ptrace (PT_GETFPREGS, tid, 0, fp);
154 warning (_("Unable to fetch the floating point registers."));
159 if (REG_VALID == regcache_register_status (regcache, ARM_FPS_REGNUM))
160 regcache_raw_collect (regcache, ARM_FPS_REGNUM, fp + NWFPE_FPSR_OFFSET);
162 /* Store the floating point registers. */
163 for (regno = ARM_F0_REGNUM; regno <= ARM_F7_REGNUM; regno++)
164 if (REG_VALID == regcache_register_status (regcache, regno))
165 collect_nwfpe_register (regcache, regno, fp);
167 if (have_ptrace_getregset == TRIBOOL_TRUE)
172 iov.iov_len = ARM_LINUX_SIZEOF_NWFPE;
174 ret = ptrace (PTRACE_SETREGSET, tid, NT_FPREGSET, &iov);
177 ret = ptrace (PTRACE_SETFPREGS, tid, 0, fp);
181 warning (_("Unable to store floating point registers."));
186 /* Fetch all general registers of the process and store into
190 fetch_regs (struct regcache *regcache)
195 /* Get the thread id for the ptrace call. */
196 tid = GET_THREAD_ID (inferior_ptid);
198 if (have_ptrace_getregset == TRIBOOL_TRUE)
202 iov.iov_base = ®s;
203 iov.iov_len = sizeof (regs);
205 ret = ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iov);
208 ret = ptrace (PTRACE_GETREGS, tid, 0, ®s);
212 warning (_("Unable to fetch general registers."));
216 aarch32_gp_regcache_supply (regcache, (uint32_t *) regs, arm_apcs_32);
220 store_regs (const struct regcache *regcache)
225 /* Get the thread id for the ptrace call. */
226 tid = GET_THREAD_ID (inferior_ptid);
228 /* Fetch the general registers. */
229 if (have_ptrace_getregset == TRIBOOL_TRUE)
233 iov.iov_base = ®s;
234 iov.iov_len = sizeof (regs);
236 ret = ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iov);
239 ret = ptrace (PTRACE_GETREGS, tid, 0, ®s);
243 warning (_("Unable to fetch general registers."));
247 aarch32_gp_regcache_collect (regcache, (uint32_t *) regs, arm_apcs_32);
249 if (have_ptrace_getregset == TRIBOOL_TRUE)
253 iov.iov_base = ®s;
254 iov.iov_len = sizeof (regs);
256 ret = ptrace (PTRACE_SETREGSET, tid, NT_PRSTATUS, &iov);
259 ret = ptrace (PTRACE_SETREGS, tid, 0, ®s);
263 warning (_("Unable to store general registers."));
268 /* Fetch all WMMX registers of the process and store into
271 #define IWMMXT_REGS_SIZE (16 * 8 + 6 * 4)
274 fetch_wmmx_regs (struct regcache *regcache)
276 char regbuf[IWMMXT_REGS_SIZE];
279 /* Get the thread id for the ptrace call. */
280 tid = GET_THREAD_ID (inferior_ptid);
282 ret = ptrace (PTRACE_GETWMMXREGS, tid, 0, regbuf);
285 warning (_("Unable to fetch WMMX registers."));
289 for (regno = 0; regno < 16; regno++)
290 regcache_raw_supply (regcache, regno + ARM_WR0_REGNUM,
293 for (regno = 0; regno < 2; regno++)
294 regcache_raw_supply (regcache, regno + ARM_WCSSF_REGNUM,
295 ®buf[16 * 8 + regno * 4]);
297 for (regno = 0; regno < 4; regno++)
298 regcache_raw_supply (regcache, regno + ARM_WCGR0_REGNUM,
299 ®buf[16 * 8 + 2 * 4 + regno * 4]);
303 store_wmmx_regs (const struct regcache *regcache)
305 char regbuf[IWMMXT_REGS_SIZE];
308 /* Get the thread id for the ptrace call. */
309 tid = GET_THREAD_ID (inferior_ptid);
311 ret = ptrace (PTRACE_GETWMMXREGS, tid, 0, regbuf);
314 warning (_("Unable to fetch WMMX registers."));
318 for (regno = 0; regno < 16; regno++)
319 if (REG_VALID == regcache_register_status (regcache,
320 regno + ARM_WR0_REGNUM))
321 regcache_raw_collect (regcache, regno + ARM_WR0_REGNUM,
324 for (regno = 0; regno < 2; regno++)
325 if (REG_VALID == regcache_register_status (regcache,
326 regno + ARM_WCSSF_REGNUM))
327 regcache_raw_collect (regcache, regno + ARM_WCSSF_REGNUM,
328 ®buf[16 * 8 + regno * 4]);
330 for (regno = 0; regno < 4; regno++)
331 if (REG_VALID == regcache_register_status (regcache,
332 regno + ARM_WCGR0_REGNUM))
333 regcache_raw_collect (regcache, regno + ARM_WCGR0_REGNUM,
334 ®buf[16 * 8 + 2 * 4 + regno * 4]);
336 ret = ptrace (PTRACE_SETWMMXREGS, tid, 0, regbuf);
340 warning (_("Unable to store WMMX registers."));
346 fetch_vfp_regs (struct regcache *regcache)
348 gdb_byte regbuf[VFP_REGS_SIZE];
350 struct gdbarch *gdbarch = get_regcache_arch (regcache);
351 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
353 /* Get the thread id for the ptrace call. */
354 tid = GET_THREAD_ID (inferior_ptid);
356 if (have_ptrace_getregset == TRIBOOL_TRUE)
360 iov.iov_base = regbuf;
361 iov.iov_len = VFP_REGS_SIZE;
362 ret = ptrace (PTRACE_GETREGSET, tid, NT_ARM_VFP, &iov);
365 ret = ptrace (PTRACE_GETVFPREGS, tid, 0, regbuf);
369 warning (_("Unable to fetch VFP registers."));
373 aarch32_vfp_regcache_supply (regcache, regbuf,
374 tdep->vfp_register_count);
378 store_vfp_regs (const struct regcache *regcache)
380 gdb_byte regbuf[VFP_REGS_SIZE];
382 struct gdbarch *gdbarch = get_regcache_arch (regcache);
383 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
385 /* Get the thread id for the ptrace call. */
386 tid = GET_THREAD_ID (inferior_ptid);
388 if (have_ptrace_getregset == TRIBOOL_TRUE)
392 iov.iov_base = regbuf;
393 iov.iov_len = VFP_REGS_SIZE;
394 ret = ptrace (PTRACE_GETREGSET, tid, NT_ARM_VFP, &iov);
397 ret = ptrace (PTRACE_GETVFPREGS, tid, 0, regbuf);
401 warning (_("Unable to fetch VFP registers (for update)."));
405 aarch32_vfp_regcache_collect (regcache, regbuf,
406 tdep->vfp_register_count);
408 if (have_ptrace_getregset == TRIBOOL_TRUE)
412 iov.iov_base = regbuf;
413 iov.iov_len = VFP_REGS_SIZE;
414 ret = ptrace (PTRACE_SETREGSET, tid, NT_ARM_VFP, &iov);
417 ret = ptrace (PTRACE_SETVFPREGS, tid, 0, regbuf);
421 warning (_("Unable to store VFP registers."));
426 /* Fetch registers from the child process. Fetch all registers if
427 regno == -1, otherwise fetch all general registers or all floating
428 point registers depending upon the value of regno. */
431 arm_linux_fetch_inferior_registers (struct target_ops *ops,
432 struct regcache *regcache, int regno)
434 struct gdbarch *gdbarch = get_regcache_arch (regcache);
435 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
439 fetch_regs (regcache);
440 fetch_fpregs (regcache);
441 if (tdep->have_wmmx_registers)
442 fetch_wmmx_regs (regcache);
443 if (tdep->vfp_register_count > 0)
444 fetch_vfp_regs (regcache);
448 if (regno < ARM_F0_REGNUM || regno == ARM_PS_REGNUM)
449 fetch_regs (regcache);
450 else if (regno >= ARM_F0_REGNUM && regno <= ARM_FPS_REGNUM)
451 fetch_fpregs (regcache);
452 else if (tdep->have_wmmx_registers
453 && regno >= ARM_WR0_REGNUM && regno <= ARM_WCGR7_REGNUM)
454 fetch_wmmx_regs (regcache);
455 else if (tdep->vfp_register_count > 0
456 && regno >= ARM_D0_REGNUM
457 && regno <= ARM_D0_REGNUM + tdep->vfp_register_count)
458 fetch_vfp_regs (regcache);
462 /* Store registers back into the inferior. Store all registers if
463 regno == -1, otherwise store all general registers or all floating
464 point registers depending upon the value of regno. */
467 arm_linux_store_inferior_registers (struct target_ops *ops,
468 struct regcache *regcache, int regno)
470 struct gdbarch *gdbarch = get_regcache_arch (regcache);
471 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
475 store_regs (regcache);
476 store_fpregs (regcache);
477 if (tdep->have_wmmx_registers)
478 store_wmmx_regs (regcache);
479 if (tdep->vfp_register_count > 0)
480 store_vfp_regs (regcache);
484 if (regno < ARM_F0_REGNUM || regno == ARM_PS_REGNUM)
485 store_regs (regcache);
486 else if ((regno >= ARM_F0_REGNUM) && (regno <= ARM_FPS_REGNUM))
487 store_fpregs (regcache);
488 else if (tdep->have_wmmx_registers
489 && regno >= ARM_WR0_REGNUM && regno <= ARM_WCGR7_REGNUM)
490 store_wmmx_regs (regcache);
491 else if (tdep->vfp_register_count > 0
492 && regno >= ARM_D0_REGNUM
493 && regno <= ARM_D0_REGNUM + tdep->vfp_register_count)
494 store_vfp_regs (regcache);
498 /* Wrapper functions for the standard regset handling, used by
502 fill_gregset (const struct regcache *regcache,
503 gdb_gregset_t *gregsetp, int regno)
505 arm_linux_collect_gregset (NULL, regcache, regno, gregsetp, 0);
509 supply_gregset (struct regcache *regcache, const gdb_gregset_t *gregsetp)
511 arm_linux_supply_gregset (NULL, regcache, -1, gregsetp, 0);
515 fill_fpregset (const struct regcache *regcache,
516 gdb_fpregset_t *fpregsetp, int regno)
518 arm_linux_collect_nwfpe (NULL, regcache, regno, fpregsetp, 0);
521 /* Fill GDB's register array with the floating-point register values
525 supply_fpregset (struct regcache *regcache, const gdb_fpregset_t *fpregsetp)
527 arm_linux_supply_nwfpe (NULL, regcache, -1, fpregsetp, 0);
530 /* Fetch the thread-local storage pointer for libthread_db. */
533 ps_get_thread_area (const struct ps_prochandle *ph,
534 lwpid_t lwpid, int idx, void **base)
536 if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
539 /* IDX is the bias from the thread pointer to the beginning of the
540 thread descriptor. It has to be subtracted due to implementation
541 quirks in libthread_db. */
542 *base = (void *) ((char *)*base - idx);
547 static const struct target_desc *
548 arm_linux_read_description (struct target_ops *ops)
550 CORE_ADDR arm_hwcap = 0;
552 if (have_ptrace_getregset == TRIBOOL_UNKNOWN)
554 elf_gregset_t gpregs;
556 int tid = GET_THREAD_ID (inferior_ptid);
558 iov.iov_base = &gpregs;
559 iov.iov_len = sizeof (gpregs);
561 /* Check if PTRACE_GETREGSET works. */
562 if (ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iov) < 0)
563 have_ptrace_getregset = TRIBOOL_FALSE;
565 have_ptrace_getregset = TRIBOOL_TRUE;
568 if (target_auxv_search (ops, AT_HWCAP, &arm_hwcap) != 1)
570 return ops->beneath->to_read_description (ops->beneath);
573 if (arm_hwcap & HWCAP_IWMMXT)
574 return tdesc_arm_with_iwmmxt;
576 if (arm_hwcap & HWCAP_VFP)
580 const struct target_desc * result = NULL;
582 /* NEON implies VFPv3-D32 or no-VFP unit. Say that we only support
583 Neon with VFPv3-D32. */
584 if (arm_hwcap & HWCAP_NEON)
585 result = tdesc_arm_with_neon;
586 else if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPv3D16)) == HWCAP_VFPv3)
587 result = tdesc_arm_with_vfpv3;
589 result = tdesc_arm_with_vfpv2;
591 /* Now make sure that the kernel supports reading these
592 registers. Support was added in 2.6.30. */
593 pid = ptid_get_lwp (inferior_ptid);
595 buf = alloca (VFP_REGS_SIZE);
596 if (ptrace (PTRACE_GETVFPREGS, pid, 0, buf) < 0
603 return ops->beneath->to_read_description (ops->beneath);
606 /* Information describing the hardware breakpoint capabilities. */
607 struct arm_linux_hwbp_cap
610 gdb_byte max_wp_length;
615 /* Since we cannot dynamically allocate subfields of arm_linux_process_info,
616 assume a maximum number of supported break-/watchpoints. */
620 /* Get hold of the Hardware Breakpoint information for the target we are
621 attached to. Returns NULL if the kernel doesn't support Hardware
622 breakpoints at all, or a pointer to the information structure. */
623 static const struct arm_linux_hwbp_cap *
624 arm_linux_get_hwbp_cap (void)
626 /* The info structure we return. */
627 static struct arm_linux_hwbp_cap info;
629 /* Is INFO in a good state? -1 means that no attempt has been made to
630 initialize INFO; 0 means an attempt has been made, but it failed; 1
631 means INFO is in an initialized state. */
632 static int available = -1;
639 tid = GET_THREAD_ID (inferior_ptid);
640 if (ptrace (PTRACE_GETHBPREGS, tid, 0, &val) < 0)
644 info.arch = (gdb_byte)((val >> 24) & 0xff);
645 info.max_wp_length = (gdb_byte)((val >> 16) & 0xff);
646 info.wp_count = (gdb_byte)((val >> 8) & 0xff);
647 info.bp_count = (gdb_byte)(val & 0xff);
649 if (info.wp_count > MAX_WPTS)
651 warning (_("arm-linux-gdb supports %d hardware watchpoints but target \
652 supports %d"), MAX_WPTS, info.wp_count);
653 info.wp_count = MAX_WPTS;
656 if (info.bp_count > MAX_BPTS)
658 warning (_("arm-linux-gdb supports %d hardware breakpoints but target \
659 supports %d"), MAX_BPTS, info.bp_count);
660 info.bp_count = MAX_BPTS;
662 available = (info.arch != 0);
666 return available == 1 ? &info : NULL;
669 /* How many hardware breakpoints are available? */
671 arm_linux_get_hw_breakpoint_count (void)
673 const struct arm_linux_hwbp_cap *cap = arm_linux_get_hwbp_cap ();
674 return cap != NULL ? cap->bp_count : 0;
677 /* How many hardware watchpoints are available? */
679 arm_linux_get_hw_watchpoint_count (void)
681 const struct arm_linux_hwbp_cap *cap = arm_linux_get_hwbp_cap ();
682 return cap != NULL ? cap->wp_count : 0;
685 /* Have we got a free break-/watch-point available for use? Returns -1 if
686 there is not an appropriate resource available, otherwise returns 1. */
688 arm_linux_can_use_hw_breakpoint (struct target_ops *self,
689 int type, int cnt, int ot)
691 if (type == bp_hardware_watchpoint || type == bp_read_watchpoint
692 || type == bp_access_watchpoint || type == bp_watchpoint)
694 int count = arm_linux_get_hw_watchpoint_count ();
698 else if (cnt + ot > count)
701 else if (type == bp_hardware_breakpoint)
703 int count = arm_linux_get_hw_breakpoint_count ();
707 else if (cnt > count)
716 /* Enum describing the different types of ARM hardware break-/watch-points. */
725 /* Type describing an ARM Hardware Breakpoint Control register value. */
726 typedef unsigned int arm_hwbp_control_t;
728 /* Structure used to keep track of hardware break-/watch-points. */
729 struct arm_linux_hw_breakpoint
731 /* Address to break on, or being watched. */
732 unsigned int address;
733 /* Control register for break-/watch- point. */
734 arm_hwbp_control_t control;
737 /* Structure containing arrays of per process hardware break-/watchpoints
738 for caching address and control information.
740 The Linux ptrace interface to hardware break-/watch-points presents the
741 values in a vector centred around 0 (which is used fo generic information).
742 Positive indicies refer to breakpoint addresses/control registers, negative
743 indices to watchpoint addresses/control registers.
745 The Linux vector is indexed as follows:
746 -((i << 1) + 2): Control register for watchpoint i.
747 -((i << 1) + 1): Address register for watchpoint i.
748 0: Information register.
749 ((i << 1) + 1): Address register for breakpoint i.
750 ((i << 1) + 2): Control register for breakpoint i.
752 This structure is used as a per-thread cache of the state stored by the
753 kernel, so that we don't need to keep calling into the kernel to find a
756 We treat break-/watch-points with their enable bit clear as being deleted.
758 struct arm_linux_debug_reg_state
760 /* Hardware breakpoints for this process. */
761 struct arm_linux_hw_breakpoint bpts[MAX_BPTS];
762 /* Hardware watchpoints for this process. */
763 struct arm_linux_hw_breakpoint wpts[MAX_WPTS];
766 /* Per-process arch-specific data we want to keep. */
767 struct arm_linux_process_info
770 struct arm_linux_process_info *next;
771 /* The process identifier. */
773 /* Hardware break-/watchpoints state information. */
774 struct arm_linux_debug_reg_state state;
778 /* Per-thread arch-specific data we want to keep. */
781 /* Non-zero if our copy differs from what's recorded in the thread. */
782 char bpts_changed[MAX_BPTS];
783 char wpts_changed[MAX_WPTS];
786 static struct arm_linux_process_info *arm_linux_process_list = NULL;
788 /* Find process data for process PID. */
790 static struct arm_linux_process_info *
791 arm_linux_find_process_pid (pid_t pid)
793 struct arm_linux_process_info *proc;
795 for (proc = arm_linux_process_list; proc; proc = proc->next)
796 if (proc->pid == pid)
802 /* Add process data for process PID. Returns newly allocated info
805 static struct arm_linux_process_info *
806 arm_linux_add_process (pid_t pid)
808 struct arm_linux_process_info *proc;
810 proc = xcalloc (1, sizeof (*proc));
813 proc->next = arm_linux_process_list;
814 arm_linux_process_list = proc;
819 /* Get data specific info for process PID, creating it if necessary.
820 Never returns NULL. */
822 static struct arm_linux_process_info *
823 arm_linux_process_info_get (pid_t pid)
825 struct arm_linux_process_info *proc;
827 proc = arm_linux_find_process_pid (pid);
829 proc = arm_linux_add_process (pid);
834 /* Called whenever GDB is no longer debugging process PID. It deletes
835 data structures that keep track of debug register state. */
838 arm_linux_forget_process (pid_t pid)
840 struct arm_linux_process_info *proc, **proc_link;
842 proc = arm_linux_process_list;
843 proc_link = &arm_linux_process_list;
847 if (proc->pid == pid)
849 *proc_link = proc->next;
855 proc_link = &proc->next;
860 /* Get hardware break-/watchpoint state for process PID. */
862 static struct arm_linux_debug_reg_state *
863 arm_linux_get_debug_reg_state (pid_t pid)
865 return &arm_linux_process_info_get (pid)->state;
868 /* Initialize an ARM hardware break-/watch-point control register value.
869 BYTE_ADDRESS_SELECT is the mask of bytes to trigger on; HWBP_TYPE is the
870 type of break-/watch-point; ENABLE indicates whether the point is enabled.
872 static arm_hwbp_control_t
873 arm_hwbp_control_initialize (unsigned byte_address_select,
874 arm_hwbp_type hwbp_type,
877 gdb_assert ((byte_address_select & ~0xffU) == 0);
878 gdb_assert (hwbp_type != arm_hwbp_break
879 || ((byte_address_select & 0xfU) != 0));
881 return (byte_address_select << 5) | (hwbp_type << 3) | (3 << 1) | enable;
884 /* Does the breakpoint control value CONTROL have the enable bit set? */
886 arm_hwbp_control_is_enabled (arm_hwbp_control_t control)
888 return control & 0x1;
891 /* Change a breakpoint control word so that it is in the disabled state. */
892 static arm_hwbp_control_t
893 arm_hwbp_control_disable (arm_hwbp_control_t control)
895 return control & ~0x1;
898 /* Initialise the hardware breakpoint structure P. The breakpoint will be
899 enabled, and will point to the placed address of BP_TGT. */
901 arm_linux_hw_breakpoint_initialize (struct gdbarch *gdbarch,
902 struct bp_target_info *bp_tgt,
903 struct arm_linux_hw_breakpoint *p)
906 CORE_ADDR address = bp_tgt->placed_address = bp_tgt->reqstd_address;
908 /* We have to create a mask for the control register which says which bits
909 of the word pointed to by address to break on. */
910 if (arm_pc_is_thumb (gdbarch, address))
921 p->address = (unsigned int) address;
922 p->control = arm_hwbp_control_initialize (mask, arm_hwbp_break, 1);
925 /* Get the ARM hardware breakpoint type from the RW value we're given when
926 asked to set a watchpoint. */
928 arm_linux_get_hwbp_type (int rw)
931 return arm_hwbp_load;
932 else if (rw == hw_write)
933 return arm_hwbp_store;
935 return arm_hwbp_access;
938 /* Initialize the hardware breakpoint structure P for a watchpoint at ADDR
939 to LEN. The type of watchpoint is given in RW. */
941 arm_linux_hw_watchpoint_initialize (CORE_ADDR addr, int len, int rw,
942 struct arm_linux_hw_breakpoint *p)
944 const struct arm_linux_hwbp_cap *cap = arm_linux_get_hwbp_cap ();
947 gdb_assert (cap != NULL);
948 gdb_assert (cap->max_wp_length != 0);
950 mask = (1 << len) - 1;
952 p->address = (unsigned int) addr;
953 p->control = arm_hwbp_control_initialize (mask,
954 arm_linux_get_hwbp_type (rw), 1);
957 /* Are two break-/watch-points equal? */
959 arm_linux_hw_breakpoint_equal (const struct arm_linux_hw_breakpoint *p1,
960 const struct arm_linux_hw_breakpoint *p2)
962 return p1->address == p2->address && p1->control == p2->control;
965 /* Callback to mark a watch-/breakpoint to be updated in all threads of
966 the current process. */
968 struct update_registers_data
975 update_registers_callback (struct lwp_info *lwp, void *arg)
977 struct update_registers_data *data = (struct update_registers_data *) arg;
979 if (lwp->arch_private == NULL)
980 lwp->arch_private = XCNEW (struct arch_lwp_info);
982 /* The actual update is done later just before resuming the lwp,
983 we just mark that the registers need updating. */
985 lwp->arch_private->wpts_changed[data->index] = 1;
987 lwp->arch_private->bpts_changed[data->index] = 1;
989 /* If the lwp isn't stopped, force it to momentarily pause, so
990 we can update its breakpoint registers. */
992 linux_stop_lwp (lwp);
997 /* Insert the hardware breakpoint (WATCHPOINT = 0) or watchpoint (WATCHPOINT
998 =1) BPT for thread TID. */
1000 arm_linux_insert_hw_breakpoint1 (const struct arm_linux_hw_breakpoint* bpt,
1006 struct arm_linux_hw_breakpoint* bpts;
1007 struct update_registers_data data;
1009 pid = ptid_get_pid (inferior_ptid);
1010 pid_ptid = pid_to_ptid (pid);
1014 count = arm_linux_get_hw_watchpoint_count ();
1015 bpts = arm_linux_get_debug_reg_state (pid)->wpts;
1019 count = arm_linux_get_hw_breakpoint_count ();
1020 bpts = arm_linux_get_debug_reg_state (pid)->bpts;
1023 for (i = 0; i < count; ++i)
1024 if (!arm_hwbp_control_is_enabled (bpts[i].control))
1026 data.watch = watchpoint;
1029 iterate_over_lwps (pid_ptid, update_registers_callback, &data);
1033 gdb_assert (i != count);
1036 /* Remove the hardware breakpoint (WATCHPOINT = 0) or watchpoint
1037 (WATCHPOINT = 1) BPT for thread TID. */
1039 arm_linux_remove_hw_breakpoint1 (const struct arm_linux_hw_breakpoint *bpt,
1045 struct arm_linux_hw_breakpoint* bpts;
1046 struct update_registers_data data;
1048 pid = ptid_get_pid (inferior_ptid);
1049 pid_ptid = pid_to_ptid (pid);
1053 count = arm_linux_get_hw_watchpoint_count ();
1054 bpts = arm_linux_get_debug_reg_state (pid)->wpts;
1058 count = arm_linux_get_hw_breakpoint_count ();
1059 bpts = arm_linux_get_debug_reg_state (pid)->bpts;
1062 for (i = 0; i < count; ++i)
1063 if (arm_linux_hw_breakpoint_equal (bpt, bpts + i))
1065 data.watch = watchpoint;
1067 bpts[i].control = arm_hwbp_control_disable (bpts[i].control);
1068 iterate_over_lwps (pid_ptid, update_registers_callback, &data);
1072 gdb_assert (i != count);
1075 /* Insert a Hardware breakpoint. */
1077 arm_linux_insert_hw_breakpoint (struct target_ops *self,
1078 struct gdbarch *gdbarch,
1079 struct bp_target_info *bp_tgt)
1081 struct lwp_info *lp;
1082 struct arm_linux_hw_breakpoint p;
1084 if (arm_linux_get_hw_breakpoint_count () == 0)
1087 arm_linux_hw_breakpoint_initialize (gdbarch, bp_tgt, &p);
1089 arm_linux_insert_hw_breakpoint1 (&p, 0);
1094 /* Remove a hardware breakpoint. */
1096 arm_linux_remove_hw_breakpoint (struct target_ops *self,
1097 struct gdbarch *gdbarch,
1098 struct bp_target_info *bp_tgt)
1100 struct lwp_info *lp;
1101 struct arm_linux_hw_breakpoint p;
1103 if (arm_linux_get_hw_breakpoint_count () == 0)
1106 arm_linux_hw_breakpoint_initialize (gdbarch, bp_tgt, &p);
1108 arm_linux_remove_hw_breakpoint1 (&p, 0);
1113 /* Are we able to use a hardware watchpoint for the LEN bytes starting at
1116 arm_linux_region_ok_for_hw_watchpoint (struct target_ops *self,
1117 CORE_ADDR addr, int len)
1119 const struct arm_linux_hwbp_cap *cap = arm_linux_get_hwbp_cap ();
1120 CORE_ADDR max_wp_length, aligned_addr;
1122 /* Can not set watchpoints for zero or negative lengths. */
1126 /* Need to be able to use the ptrace interface. */
1127 if (cap == NULL || cap->wp_count == 0)
1130 /* Test that the range [ADDR, ADDR + LEN) fits into the largest address
1131 range covered by a watchpoint. */
1132 max_wp_length = (CORE_ADDR)cap->max_wp_length;
1133 aligned_addr = addr & ~(max_wp_length - 1);
1135 if (aligned_addr + max_wp_length < addr + len)
1138 /* The current ptrace interface can only handle watchpoints that are a
1140 if ((len & (len - 1)) != 0)
1143 /* All tests passed so we must be able to set a watchpoint. */
1147 /* Insert a Hardware breakpoint. */
1149 arm_linux_insert_watchpoint (struct target_ops *self,
1150 CORE_ADDR addr, int len, int rw,
1151 struct expression *cond)
1153 struct lwp_info *lp;
1154 struct arm_linux_hw_breakpoint p;
1156 if (arm_linux_get_hw_watchpoint_count () == 0)
1159 arm_linux_hw_watchpoint_initialize (addr, len, rw, &p);
1161 arm_linux_insert_hw_breakpoint1 (&p, 1);
1166 /* Remove a hardware breakpoint. */
1168 arm_linux_remove_watchpoint (struct target_ops *self,
1169 CORE_ADDR addr, int len, int rw,
1170 struct expression *cond)
1172 struct lwp_info *lp;
1173 struct arm_linux_hw_breakpoint p;
1175 if (arm_linux_get_hw_watchpoint_count () == 0)
1178 arm_linux_hw_watchpoint_initialize (addr, len, rw, &p);
1180 arm_linux_remove_hw_breakpoint1 (&p, 1);
1185 /* What was the data address the target was stopped on accessing. */
1187 arm_linux_stopped_data_address (struct target_ops *target, CORE_ADDR *addr_p)
1192 if (!linux_nat_get_siginfo (inferior_ptid, &siginfo))
1195 /* This must be a hardware breakpoint. */
1196 if (siginfo.si_signo != SIGTRAP
1197 || (siginfo.si_code & 0xffff) != 0x0004 /* TRAP_HWBKPT */)
1200 /* We must be able to set hardware watchpoints. */
1201 if (arm_linux_get_hw_watchpoint_count () == 0)
1204 slot = siginfo.si_errno;
1206 /* If we are in a positive slot then we're looking at a breakpoint and not
1211 *addr_p = (CORE_ADDR) (uintptr_t) siginfo.si_addr;
1215 /* Has the target been stopped by hitting a watchpoint? */
1217 arm_linux_stopped_by_watchpoint (struct target_ops *ops)
1220 return arm_linux_stopped_data_address (ops, &addr);
1224 arm_linux_watchpoint_addr_within_range (struct target_ops *target,
1226 CORE_ADDR start, int length)
1228 return start <= addr && start + length - 1 >= addr;
1231 /* Handle thread creation. We need to copy the breakpoints and watchpoints
1232 in the parent thread to the child thread. */
1234 arm_linux_new_thread (struct lwp_info *lp)
1237 struct arch_lwp_info *info = XCNEW (struct arch_lwp_info);
1239 /* Mark that all the hardware breakpoint/watchpoint register pairs
1240 for this thread need to be initialized. */
1242 for (i = 0; i < MAX_BPTS; i++)
1244 info->bpts_changed[i] = 1;
1245 info->wpts_changed[i] = 1;
1248 lp->arch_private = info;
1251 /* Called when resuming a thread.
1252 The hardware debug registers are updated when there is any change. */
1255 arm_linux_prepare_to_resume (struct lwp_info *lwp)
1258 struct arm_linux_hw_breakpoint *bpts, *wpts;
1259 struct arch_lwp_info *arm_lwp_info = lwp->arch_private;
1261 pid = ptid_get_lwp (lwp->ptid);
1262 bpts = arm_linux_get_debug_reg_state (ptid_get_pid (lwp->ptid))->bpts;
1263 wpts = arm_linux_get_debug_reg_state (ptid_get_pid (lwp->ptid))->wpts;
1265 /* NULL means this is the main thread still going through the shell,
1266 or, no watchpoint has been set yet. In that case, there's
1268 if (arm_lwp_info == NULL)
1271 for (i = 0; i < arm_linux_get_hw_breakpoint_count (); i++)
1272 if (arm_lwp_info->bpts_changed[i])
1275 if (arm_hwbp_control_is_enabled (bpts[i].control))
1276 if (ptrace (PTRACE_SETHBPREGS, pid,
1277 (PTRACE_TYPE_ARG3) ((i << 1) + 1), &bpts[i].address) < 0)
1278 perror_with_name (_("Unexpected error setting breakpoint"));
1280 if (bpts[i].control != 0)
1281 if (ptrace (PTRACE_SETHBPREGS, pid,
1282 (PTRACE_TYPE_ARG3) ((i << 1) + 2), &bpts[i].control) < 0)
1283 perror_with_name (_("Unexpected error setting breakpoint"));
1285 arm_lwp_info->bpts_changed[i] = 0;
1288 for (i = 0; i < arm_linux_get_hw_watchpoint_count (); i++)
1289 if (arm_lwp_info->wpts_changed[i])
1292 if (arm_hwbp_control_is_enabled (wpts[i].control))
1293 if (ptrace (PTRACE_SETHBPREGS, pid,
1294 (PTRACE_TYPE_ARG3) -((i << 1) + 1), &wpts[i].address) < 0)
1295 perror_with_name (_("Unexpected error setting watchpoint"));
1297 if (wpts[i].control != 0)
1298 if (ptrace (PTRACE_SETHBPREGS, pid,
1299 (PTRACE_TYPE_ARG3) -((i << 1) + 2), &wpts[i].control) < 0)
1300 perror_with_name (_("Unexpected error setting watchpoint"));
1302 arm_lwp_info->wpts_changed[i] = 0;
1306 /* linux_nat_new_fork hook. */
1309 arm_linux_new_fork (struct lwp_info *parent, pid_t child_pid)
1312 struct arm_linux_debug_reg_state *parent_state;
1313 struct arm_linux_debug_reg_state *child_state;
1315 /* NULL means no watchpoint has ever been set in the parent. In
1316 that case, there's nothing to do. */
1317 if (parent->arch_private == NULL)
1320 /* GDB core assumes the child inherits the watchpoints/hw
1321 breakpoints of the parent, and will remove them all from the
1322 forked off process. Copy the debug registers mirrors into the
1323 new process so that all breakpoints and watchpoints can be
1324 removed together. */
1326 parent_pid = ptid_get_pid (parent->ptid);
1327 parent_state = arm_linux_get_debug_reg_state (parent_pid);
1328 child_state = arm_linux_get_debug_reg_state (child_pid);
1329 *child_state = *parent_state;
1332 void _initialize_arm_linux_nat (void);
1335 _initialize_arm_linux_nat (void)
1337 struct target_ops *t;
1339 /* Fill in the generic GNU/Linux methods. */
1340 t = linux_target ();
1342 /* Add our register access methods. */
1343 t->to_fetch_registers = arm_linux_fetch_inferior_registers;
1344 t->to_store_registers = arm_linux_store_inferior_registers;
1346 /* Add our hardware breakpoint and watchpoint implementation. */
1347 t->to_can_use_hw_breakpoint = arm_linux_can_use_hw_breakpoint;
1348 t->to_insert_hw_breakpoint = arm_linux_insert_hw_breakpoint;
1349 t->to_remove_hw_breakpoint = arm_linux_remove_hw_breakpoint;
1350 t->to_region_ok_for_hw_watchpoint = arm_linux_region_ok_for_hw_watchpoint;
1351 t->to_insert_watchpoint = arm_linux_insert_watchpoint;
1352 t->to_remove_watchpoint = arm_linux_remove_watchpoint;
1353 t->to_stopped_by_watchpoint = arm_linux_stopped_by_watchpoint;
1354 t->to_stopped_data_address = arm_linux_stopped_data_address;
1355 t->to_watchpoint_addr_within_range = arm_linux_watchpoint_addr_within_range;
1357 t->to_read_description = arm_linux_read_description;
1359 /* Register the target. */
1360 linux_nat_add_target (t);
1362 /* Handle thread creation and exit. */
1363 linux_nat_set_new_thread (t, arm_linux_new_thread);
1364 linux_nat_set_prepare_to_resume (t, arm_linux_prepare_to_resume);
1366 /* Handle process creation and exit. */
1367 linux_nat_set_new_fork (t, arm_linux_new_fork);
1368 linux_nat_set_forget_process (t, arm_linux_forget_process);