1 /* GNU/Linux/ARM specific low level interface, for the remote server for GDB.
2 Copyright (C) 1995-2016 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/>. */
20 #include "linux-low.h"
22 #include "arch/arm-linux.h"
23 #include "arch/arm-get-next-pcs.h"
24 #include "linux-aarch32-low.h"
27 /* Don't include elf.h if linux/elf.h got included by gdb_proc_service.h.
28 On Bionic elf.h and linux/elf.h have conflicting definitions. */
32 #include "nat/gdb_ptrace.h"
34 #include <sys/syscall.h>
36 /* Defined in auto-generated files. */
37 void init_registers_arm (void);
38 extern const struct target_desc *tdesc_arm;
40 void init_registers_arm_with_iwmmxt (void);
41 extern const struct target_desc *tdesc_arm_with_iwmmxt;
43 void init_registers_arm_with_vfpv2 (void);
44 extern const struct target_desc *tdesc_arm_with_vfpv2;
46 void init_registers_arm_with_vfpv3 (void);
47 extern const struct target_desc *tdesc_arm_with_vfpv3;
49 #ifndef PTRACE_GET_THREAD_AREA
50 #define PTRACE_GET_THREAD_AREA 22
53 #ifndef PTRACE_GETWMMXREGS
54 # define PTRACE_GETWMMXREGS 18
55 # define PTRACE_SETWMMXREGS 19
58 #ifndef PTRACE_GETVFPREGS
59 # define PTRACE_GETVFPREGS 27
60 # define PTRACE_SETVFPREGS 28
63 #ifndef PTRACE_GETHBPREGS
64 #define PTRACE_GETHBPREGS 29
65 #define PTRACE_SETHBPREGS 30
68 /* Information describing the hardware breakpoint capabilities. */
72 unsigned char max_wp_length;
73 unsigned char wp_count;
74 unsigned char bp_count;
77 /* Enum describing the different types of ARM hardware break-/watch-points. */
86 /* Type describing an ARM Hardware Breakpoint Control register value. */
87 typedef unsigned int arm_hwbp_control_t;
89 /* Structure used to keep track of hardware break-/watch-points. */
90 struct arm_linux_hw_breakpoint
92 /* Address to break on, or being watched. */
94 /* Control register for break-/watch- point. */
95 arm_hwbp_control_t control;
98 /* Since we cannot dynamically allocate subfields of arch_process_info,
99 assume a maximum number of supported break-/watchpoints. */
103 /* Per-process arch-specific data we want to keep. */
104 struct arch_process_info
106 /* Hardware breakpoints for this process. */
107 struct arm_linux_hw_breakpoint bpts[MAX_BPTS];
108 /* Hardware watchpoints for this process. */
109 struct arm_linux_hw_breakpoint wpts[MAX_WPTS];
112 /* Per-thread arch-specific data we want to keep. */
115 /* Non-zero if our copy differs from what's recorded in the thread. */
116 char bpts_changed[MAX_BPTS];
117 char wpts_changed[MAX_WPTS];
118 /* Cached stopped data address. */
119 CORE_ADDR stopped_data_address;
122 /* These are in <asm/elf.h> in current kernels. */
124 #define HWCAP_IWMMXT 512
125 #define HWCAP_NEON 4096
126 #define HWCAP_VFPv3 8192
127 #define HWCAP_VFPv3D16 16384
129 #ifdef HAVE_SYS_REG_H
133 #define arm_num_regs 26
135 static int arm_regmap[] = {
136 0, 4, 8, 12, 16, 20, 24, 28,
137 32, 36, 40, 44, 48, 52, 56, 60,
138 -1, -1, -1, -1, -1, -1, -1, -1, -1,
142 /* Forward declarations needed for get_next_pcs ops. */
143 static ULONGEST get_next_pcs_read_memory_unsigned_integer (CORE_ADDR memaddr,
147 static CORE_ADDR get_next_pcs_addr_bits_remove (struct arm_get_next_pcs *self,
150 static CORE_ADDR get_next_pcs_syscall_next_pc (struct arm_get_next_pcs *self);
152 static int get_next_pcs_is_thumb (struct arm_get_next_pcs *self);
154 /* get_next_pcs operations. */
155 static struct arm_get_next_pcs_ops get_next_pcs_ops = {
156 get_next_pcs_read_memory_unsigned_integer,
157 get_next_pcs_syscall_next_pc,
158 get_next_pcs_addr_bits_remove,
159 get_next_pcs_is_thumb,
160 arm_linux_get_next_pcs_fixup,
164 arm_cannot_store_register (int regno)
166 return (regno >= arm_num_regs);
170 arm_cannot_fetch_register (int regno)
172 return (regno >= arm_num_regs);
176 arm_fill_wmmxregset (struct regcache *regcache, void *buf)
180 if (regcache->tdesc != tdesc_arm_with_iwmmxt)
183 for (i = 0; i < 16; i++)
184 collect_register (regcache, arm_num_regs + i, (char *) buf + i * 8);
186 /* We only have access to wcssf, wcasf, and wcgr0-wcgr3. */
187 for (i = 0; i < 6; i++)
188 collect_register (regcache, arm_num_regs + i + 16,
189 (char *) buf + 16 * 8 + i * 4);
193 arm_store_wmmxregset (struct regcache *regcache, const void *buf)
197 if (regcache->tdesc != tdesc_arm_with_iwmmxt)
200 for (i = 0; i < 16; i++)
201 supply_register (regcache, arm_num_regs + i, (char *) buf + i * 8);
203 /* We only have access to wcssf, wcasf, and wcgr0-wcgr3. */
204 for (i = 0; i < 6; i++)
205 supply_register (regcache, arm_num_regs + i + 16,
206 (char *) buf + 16 * 8 + i * 4);
210 arm_fill_vfpregset (struct regcache *regcache, void *buf)
214 if (regcache->tdesc == tdesc_arm_with_neon
215 || regcache->tdesc == tdesc_arm_with_vfpv3)
217 else if (regcache->tdesc == tdesc_arm_with_vfpv2)
222 arm_fill_vfpregset_num (regcache, buf, num);
225 /* Wrapper of UNMAKE_THUMB_ADDR for get_next_pcs. */
227 get_next_pcs_addr_bits_remove (struct arm_get_next_pcs *self, CORE_ADDR val)
229 return UNMAKE_THUMB_ADDR (val);
233 arm_store_vfpregset (struct regcache *regcache, const void *buf)
237 if (regcache->tdesc == tdesc_arm_with_neon
238 || regcache->tdesc == tdesc_arm_with_vfpv3)
240 else if (regcache->tdesc == tdesc_arm_with_vfpv2)
245 arm_store_vfpregset_num (regcache, buf, num);
248 /* Wrapper of arm_is_thumb_mode for get_next_pcs. */
250 get_next_pcs_is_thumb (struct arm_get_next_pcs *self)
252 return arm_is_thumb_mode ();
255 /* Read memory from the inferiror.
256 BYTE_ORDER is ignored and there to keep compatiblity with GDB's
257 read_memory_unsigned_integer. */
259 get_next_pcs_read_memory_unsigned_integer (CORE_ADDR memaddr,
265 (*the_target->read_memory) (memaddr, (unsigned char *) &res, len);
269 /* Fetch the thread-local storage pointer for libthread_db. */
272 ps_get_thread_area (const struct ps_prochandle *ph,
273 lwpid_t lwpid, int idx, void **base)
275 if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
278 /* IDX is the bias from the thread pointer to the beginning of the
279 thread descriptor. It has to be subtracted due to implementation
280 quirks in libthread_db. */
281 *base = (void *) ((char *)*base - idx);
287 /* Query Hardware Breakpoint information for the target we are attached to
288 (using PID as ptrace argument) and set up arm_linux_hwbp_cap. */
290 arm_linux_init_hwbp_cap (int pid)
294 if (ptrace (PTRACE_GETHBPREGS, pid, 0, &val) < 0)
297 arm_linux_hwbp_cap.arch = (unsigned char)((val >> 24) & 0xff);
298 if (arm_linux_hwbp_cap.arch == 0)
301 arm_linux_hwbp_cap.max_wp_length = (unsigned char)((val >> 16) & 0xff);
302 arm_linux_hwbp_cap.wp_count = (unsigned char)((val >> 8) & 0xff);
303 arm_linux_hwbp_cap.bp_count = (unsigned char)(val & 0xff);
305 if (arm_linux_hwbp_cap.wp_count > MAX_WPTS)
306 internal_error (__FILE__, __LINE__, "Unsupported number of watchpoints");
307 if (arm_linux_hwbp_cap.bp_count > MAX_BPTS)
308 internal_error (__FILE__, __LINE__, "Unsupported number of breakpoints");
311 /* How many hardware breakpoints are available? */
313 arm_linux_get_hw_breakpoint_count (void)
315 return arm_linux_hwbp_cap.bp_count;
318 /* How many hardware watchpoints are available? */
320 arm_linux_get_hw_watchpoint_count (void)
322 return arm_linux_hwbp_cap.wp_count;
325 /* Maximum length of area watched by hardware watchpoint. */
327 arm_linux_get_hw_watchpoint_max_length (void)
329 return arm_linux_hwbp_cap.max_wp_length;
332 /* Initialize an ARM hardware break-/watch-point control register value.
333 BYTE_ADDRESS_SELECT is the mask of bytes to trigger on; HWBP_TYPE is the
334 type of break-/watch-point; ENABLE indicates whether the point is enabled.
336 static arm_hwbp_control_t
337 arm_hwbp_control_initialize (unsigned byte_address_select,
338 arm_hwbp_type hwbp_type,
341 gdb_assert ((byte_address_select & ~0xffU) == 0);
342 gdb_assert (hwbp_type != arm_hwbp_break
343 || ((byte_address_select & 0xfU) != 0));
345 return (byte_address_select << 5) | (hwbp_type << 3) | (3 << 1) | enable;
348 /* Does the breakpoint control value CONTROL have the enable bit set? */
350 arm_hwbp_control_is_enabled (arm_hwbp_control_t control)
352 return control & 0x1;
355 /* Is the breakpoint control value CONTROL initialized? */
357 arm_hwbp_control_is_initialized (arm_hwbp_control_t control)
362 /* Change a breakpoint control word so that it is in the disabled state. */
363 static arm_hwbp_control_t
364 arm_hwbp_control_disable (arm_hwbp_control_t control)
366 return control & ~0x1;
369 /* Are two break-/watch-points equal? */
371 arm_linux_hw_breakpoint_equal (const struct arm_linux_hw_breakpoint *p1,
372 const struct arm_linux_hw_breakpoint *p2)
374 return p1->address == p2->address && p1->control == p2->control;
377 /* Convert a raw breakpoint type to an enum arm_hwbp_type. */
380 raw_bkpt_type_to_arm_hwbp_type (enum raw_bkpt_type raw_type)
384 case raw_bkpt_type_hw:
385 return arm_hwbp_break;
386 case raw_bkpt_type_write_wp:
387 return arm_hwbp_store;
388 case raw_bkpt_type_read_wp:
389 return arm_hwbp_load;
390 case raw_bkpt_type_access_wp:
391 return arm_hwbp_access;
393 gdb_assert_not_reached ("unhandled raw type");
397 /* Initialize the hardware breakpoint structure P for a breakpoint or
398 watchpoint at ADDR to LEN. The type of watchpoint is given in TYPE.
399 Returns -1 if TYPE is unsupported, or -2 if the particular combination
400 of ADDR and LEN cannot be implemented. Otherwise, returns 0 if TYPE
401 represents a breakpoint and 1 if type represents a watchpoint. */
403 arm_linux_hw_point_initialize (enum raw_bkpt_type raw_type, CORE_ADDR addr,
404 int len, struct arm_linux_hw_breakpoint *p)
406 arm_hwbp_type hwbp_type;
409 hwbp_type = raw_bkpt_type_to_arm_hwbp_type (raw_type);
411 if (hwbp_type == arm_hwbp_break)
413 /* For breakpoints, the length field encodes the mode. */
416 case 2: /* 16-bit Thumb mode breakpoint */
417 case 3: /* 32-bit Thumb mode breakpoint */
421 case 4: /* 32-bit ARM mode breakpoint */
432 CORE_ADDR max_wp_length = arm_linux_get_hw_watchpoint_max_length ();
433 CORE_ADDR aligned_addr;
435 /* Can not set watchpoints for zero or negative lengths. */
438 /* The current ptrace interface can only handle watchpoints that are a
440 if ((len & (len - 1)) != 0)
443 /* Test that the range [ADDR, ADDR + LEN) fits into the largest address
444 range covered by a watchpoint. */
445 aligned_addr = addr & ~(max_wp_length - 1);
446 if (aligned_addr + max_wp_length < addr + len)
449 mask = (1 << len) - 1;
452 p->address = (unsigned int) addr;
453 p->control = arm_hwbp_control_initialize (mask, hwbp_type, 1);
455 return hwbp_type != arm_hwbp_break;
458 /* Callback to mark a watch-/breakpoint to be updated in all threads of
459 the current process. */
461 struct update_registers_data
468 update_registers_callback (struct inferior_list_entry *entry, void *arg)
470 struct thread_info *thread = (struct thread_info *) entry;
471 struct lwp_info *lwp = get_thread_lwp (thread);
472 struct update_registers_data *data = (struct update_registers_data *) arg;
474 /* Only update the threads of the current process. */
475 if (pid_of (thread) == pid_of (current_thread))
477 /* The actual update is done later just before resuming the lwp,
478 we just mark that the registers need updating. */
480 lwp->arch_private->wpts_changed[data->i] = 1;
482 lwp->arch_private->bpts_changed[data->i] = 1;
484 /* If the lwp isn't stopped, force it to momentarily pause, so
485 we can update its breakpoint registers. */
487 linux_stop_lwp (lwp);
494 arm_supports_z_point_type (char z_type)
500 case Z_PACKET_WRITE_WP:
501 case Z_PACKET_READ_WP:
502 case Z_PACKET_ACCESS_WP:
505 /* Leave the handling of sw breakpoints with the gdb client. */
510 /* Insert hardware break-/watchpoint. */
512 arm_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
513 int len, struct raw_breakpoint *bp)
515 struct process_info *proc = current_process ();
516 struct arm_linux_hw_breakpoint p, *pts;
519 watch = arm_linux_hw_point_initialize (type, addr, len, &p);
523 return watch == -1 ? 1 : -1;
528 count = arm_linux_get_hw_watchpoint_count ();
529 pts = proc->priv->arch_private->wpts;
533 count = arm_linux_get_hw_breakpoint_count ();
534 pts = proc->priv->arch_private->bpts;
537 for (i = 0; i < count; i++)
538 if (!arm_hwbp_control_is_enabled (pts[i].control))
540 struct update_registers_data data = { watch, i };
542 find_inferior (&all_threads, update_registers_callback, &data);
546 /* We're out of watchpoints. */
550 /* Remove hardware break-/watchpoint. */
552 arm_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
553 int len, struct raw_breakpoint *bp)
555 struct process_info *proc = current_process ();
556 struct arm_linux_hw_breakpoint p, *pts;
559 watch = arm_linux_hw_point_initialize (type, addr, len, &p);
568 count = arm_linux_get_hw_watchpoint_count ();
569 pts = proc->priv->arch_private->wpts;
573 count = arm_linux_get_hw_breakpoint_count ();
574 pts = proc->priv->arch_private->bpts;
577 for (i = 0; i < count; i++)
578 if (arm_linux_hw_breakpoint_equal (&p, pts + i))
580 struct update_registers_data data = { watch, i };
581 pts[i].control = arm_hwbp_control_disable (pts[i].control);
582 find_inferior (&all_threads, update_registers_callback, &data);
586 /* No watchpoint matched. */
590 /* Return whether current thread is stopped due to a watchpoint. */
592 arm_stopped_by_watchpoint (void)
594 struct lwp_info *lwp = get_thread_lwp (current_thread);
597 /* We must be able to set hardware watchpoints. */
598 if (arm_linux_get_hw_watchpoint_count () == 0)
601 /* Retrieve siginfo. */
603 ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread), 0, &siginfo);
607 /* This must be a hardware breakpoint. */
608 if (siginfo.si_signo != SIGTRAP
609 || (siginfo.si_code & 0xffff) != 0x0004 /* TRAP_HWBKPT */)
612 /* If we are in a positive slot then we're looking at a breakpoint and not
614 if (siginfo.si_errno >= 0)
617 /* Cache stopped data address for use by arm_stopped_data_address. */
618 lwp->arch_private->stopped_data_address
619 = (CORE_ADDR) (uintptr_t) siginfo.si_addr;
624 /* Return data address that triggered watchpoint. Called only if
625 arm_stopped_by_watchpoint returned true. */
627 arm_stopped_data_address (void)
629 struct lwp_info *lwp = get_thread_lwp (current_thread);
630 return lwp->arch_private->stopped_data_address;
633 /* Called when a new process is created. */
634 static struct arch_process_info *
635 arm_new_process (void)
637 struct arch_process_info *info = XCNEW (struct arch_process_info);
641 /* Called when a new thread is detected. */
643 arm_new_thread (struct lwp_info *lwp)
645 struct arch_lwp_info *info = XCNEW (struct arch_lwp_info);
648 for (i = 0; i < MAX_BPTS; i++)
649 info->bpts_changed[i] = 1;
650 for (i = 0; i < MAX_WPTS; i++)
651 info->wpts_changed[i] = 1;
653 lwp->arch_private = info;
657 arm_new_fork (struct process_info *parent, struct process_info *child)
659 struct arch_process_info *parent_proc_info;
660 struct arch_process_info *child_proc_info;
661 struct lwp_info *child_lwp;
662 struct arch_lwp_info *child_lwp_info;
665 /* These are allocated by linux_add_process. */
666 gdb_assert (parent->priv != NULL
667 && parent->priv->arch_private != NULL);
668 gdb_assert (child->priv != NULL
669 && child->priv->arch_private != NULL);
671 parent_proc_info = parent->priv->arch_private;
672 child_proc_info = child->priv->arch_private;
674 /* Linux kernel before 2.6.33 commit
675 72f674d203cd230426437cdcf7dd6f681dad8b0d
676 will inherit hardware debug registers from parent
677 on fork/vfork/clone. Newer Linux kernels create such tasks with
678 zeroed debug registers.
680 GDB core assumes the child inherits the watchpoints/hw
681 breakpoints of the parent, and will remove them all from the
682 forked off process. Copy the debug registers mirrors into the
683 new process so that all breakpoints and watchpoints can be
684 removed together. The debug registers mirror will become zeroed
685 in the end before detaching the forked off process, thus making
686 this compatible with older Linux kernels too. */
688 *child_proc_info = *parent_proc_info;
690 /* Mark all the hardware breakpoints and watchpoints as changed to
691 make sure that the registers will be updated. */
692 child_lwp = find_lwp_pid (ptid_of (child));
693 child_lwp_info = child_lwp->arch_private;
694 for (i = 0; i < MAX_BPTS; i++)
695 child_lwp_info->bpts_changed[i] = 1;
696 for (i = 0; i < MAX_WPTS; i++)
697 child_lwp_info->wpts_changed[i] = 1;
700 /* Called when resuming a thread.
701 If the debug regs have changed, update the thread's copies. */
703 arm_prepare_to_resume (struct lwp_info *lwp)
705 struct thread_info *thread = get_lwp_thread (lwp);
706 int pid = lwpid_of (thread);
707 struct process_info *proc = find_process_pid (pid_of (thread));
708 struct arch_process_info *proc_info = proc->priv->arch_private;
709 struct arch_lwp_info *lwp_info = lwp->arch_private;
712 for (i = 0; i < arm_linux_get_hw_breakpoint_count (); i++)
713 if (lwp_info->bpts_changed[i])
717 if (arm_hwbp_control_is_enabled (proc_info->bpts[i].control))
718 if (ptrace (PTRACE_SETHBPREGS, pid,
719 (PTRACE_TYPE_ARG3) ((i << 1) + 1),
720 &proc_info->bpts[i].address) < 0)
721 perror_with_name ("Unexpected error setting breakpoint address");
723 if (arm_hwbp_control_is_initialized (proc_info->bpts[i].control))
724 if (ptrace (PTRACE_SETHBPREGS, pid,
725 (PTRACE_TYPE_ARG3) ((i << 1) + 2),
726 &proc_info->bpts[i].control) < 0)
727 perror_with_name ("Unexpected error setting breakpoint");
729 lwp_info->bpts_changed[i] = 0;
732 for (i = 0; i < arm_linux_get_hw_watchpoint_count (); i++)
733 if (lwp_info->wpts_changed[i])
737 if (arm_hwbp_control_is_enabled (proc_info->wpts[i].control))
738 if (ptrace (PTRACE_SETHBPREGS, pid,
739 (PTRACE_TYPE_ARG3) -((i << 1) + 1),
740 &proc_info->wpts[i].address) < 0)
741 perror_with_name ("Unexpected error setting watchpoint address");
743 if (arm_hwbp_control_is_initialized (proc_info->wpts[i].control))
744 if (ptrace (PTRACE_SETHBPREGS, pid,
745 (PTRACE_TYPE_ARG3) -((i << 1) + 2),
746 &proc_info->wpts[i].control) < 0)
747 perror_with_name ("Unexpected error setting watchpoint");
749 lwp_info->wpts_changed[i] = 0;
753 /* Find the next pc for a sigreturn or rt_sigreturn syscall. In
754 addition, set IS_THUMB depending on whether we will return to ARM
756 See arm-linux.h for stack layout details. */
758 arm_sigreturn_next_pc (struct regcache *regcache, int svc_number,
762 unsigned long sp_data;
763 /* Offset of PC register. */
765 CORE_ADDR next_pc = 0;
768 gdb_assert (svc_number == __NR_sigreturn || svc_number == __NR_rt_sigreturn);
770 collect_register_by_name (regcache, "sp", &sp);
771 (*the_target->read_memory) (sp, (unsigned char *) &sp_data, 4);
773 pc_offset = arm_linux_sigreturn_next_pc_offset
774 (sp, sp_data, svc_number, __NR_sigreturn == svc_number ? 1 : 0);
776 (*the_target->read_memory) (sp + pc_offset, (unsigned char *) &next_pc, 4);
778 /* Set IS_THUMB according the CPSR saved on the stack. */
779 (*the_target->read_memory) (sp + pc_offset + 4, (unsigned char *) &cpsr, 4);
780 *is_thumb = ((cpsr & CPSR_T) != 0);
785 /* When PC is at a syscall instruction, return the PC of the next
786 instruction to be executed. */
788 get_next_pcs_syscall_next_pc (struct arm_get_next_pcs *self)
790 CORE_ADDR next_pc = 0;
791 CORE_ADDR pc = regcache_read_pc (self->regcache);
792 int is_thumb = arm_is_thumb_mode ();
793 ULONGEST svc_number = 0;
794 struct regcache *regcache = self->regcache;
798 collect_register (regcache, 7, &svc_number);
803 unsigned long this_instr;
804 unsigned long svc_operand;
806 (*the_target->read_memory) (pc, (unsigned char *) &this_instr, 4);
807 svc_operand = (0x00ffffff & this_instr);
809 if (svc_operand) /* OABI. */
811 svc_number = svc_operand - 0x900000;
815 collect_register (regcache, 7, &svc_number);
821 /* This is a sigreturn or sigreturn_rt syscall. */
822 if (svc_number == __NR_sigreturn || svc_number == __NR_rt_sigreturn)
824 /* SIGRETURN or RT_SIGRETURN may affect the arm thumb mode, so
826 next_pc = arm_sigreturn_next_pc (regcache, svc_number, &is_thumb);
829 /* Addresses for calling Thumb functions have the bit 0 set. */
831 next_pc = MAKE_THUMB_ADDR (next_pc);
837 arm_get_hwcap (unsigned long *valp)
839 unsigned char *data = (unsigned char *) alloca (8);
842 while ((*the_target->read_auxv) (offset, data, 8) == 8)
844 unsigned int *data_p = (unsigned int *)data;
845 if (data_p[0] == AT_HWCAP)
858 static const struct target_desc *
859 arm_read_description (void)
861 int pid = lwpid_of (current_thread);
862 unsigned long arm_hwcap = 0;
864 /* Query hardware watchpoint/breakpoint capabilities. */
865 arm_linux_init_hwbp_cap (pid);
867 if (arm_get_hwcap (&arm_hwcap) == 0)
870 if (arm_hwcap & HWCAP_IWMMXT)
871 return tdesc_arm_with_iwmmxt;
873 if (arm_hwcap & HWCAP_VFP)
875 const struct target_desc *result;
878 /* NEON implies either no VFP, or VFPv3-D32. We only support
880 if (arm_hwcap & HWCAP_NEON)
881 result = tdesc_arm_with_neon;
882 else if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPv3D16)) == HWCAP_VFPv3)
883 result = tdesc_arm_with_vfpv3;
885 result = tdesc_arm_with_vfpv2;
887 /* Now make sure that the kernel supports reading these
888 registers. Support was added in 2.6.30. */
890 buf = (char *) xmalloc (32 * 8 + 4);
891 if (ptrace (PTRACE_GETVFPREGS, pid, 0, buf) < 0
900 /* The default configuration uses legacy FPA registers, probably
906 arm_arch_setup (void)
908 int tid = lwpid_of (current_thread);
912 current_process ()->tdesc = arm_read_description ();
914 iov.iov_base = gpregs;
915 iov.iov_len = sizeof (gpregs);
917 /* Check if PTRACE_GETREGSET works. */
918 if (ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iov) == 0)
919 have_ptrace_getregset = 1;
921 have_ptrace_getregset = 0;
924 /* Fetch the next possible PCs after the current instruction executes. */
926 static VEC (CORE_ADDR) *
927 arm_gdbserver_get_next_pcs (struct regcache *regcache)
929 struct arm_get_next_pcs next_pcs_ctx;
930 VEC (CORE_ADDR) *next_pcs = NULL;
932 arm_get_next_pcs_ctor (&next_pcs_ctx,
934 /* Byte order is ignored assumed as host. */
940 next_pcs = arm_get_next_pcs (&next_pcs_ctx);
945 /* Support for hardware single step. */
948 arm_supports_hardware_single_step (void)
953 /* Register sets without using PTRACE_GETREGSET. */
955 static struct regset_info arm_regsets[] = {
956 { PTRACE_GETREGS, PTRACE_SETREGS, 0, 18 * 4,
958 arm_fill_gregset, arm_store_gregset },
959 { PTRACE_GETWMMXREGS, PTRACE_SETWMMXREGS, 0, 16 * 8 + 6 * 4,
961 arm_fill_wmmxregset, arm_store_wmmxregset },
962 { PTRACE_GETVFPREGS, PTRACE_SETVFPREGS, 0, 32 * 8 + 4,
964 arm_fill_vfpregset, arm_store_vfpregset },
968 static struct regsets_info arm_regsets_info =
970 arm_regsets, /* regsets */
972 NULL, /* disabled_regsets */
975 static struct usrregs_info arm_usrregs_info =
981 static struct regs_info regs_info_arm =
983 NULL, /* regset_bitmap */
988 static const struct regs_info *
991 const struct target_desc *tdesc = current_process ()->tdesc;
993 if (have_ptrace_getregset == 1
994 && (tdesc == tdesc_arm_with_neon || tdesc == tdesc_arm_with_vfpv3))
995 return ®s_info_aarch32;
997 return ®s_info_arm;
1000 struct linux_target_ops the_low_target = {
1003 arm_cannot_fetch_register,
1004 arm_cannot_store_register,
1005 NULL, /* fetch_register */
1008 arm_breakpoint_kind_from_pc,
1009 arm_sw_breakpoint_from_kind,
1010 arm_gdbserver_get_next_pcs,
1013 arm_supports_z_point_type,
1016 arm_stopped_by_watchpoint,
1017 arm_stopped_data_address,
1018 NULL, /* collect_ptrace_register */
1019 NULL, /* supply_ptrace_register */
1020 NULL, /* siginfo_fixup */
1024 arm_prepare_to_resume,
1025 NULL, /* process_qsupported */
1026 NULL, /* supports_tracepoints */
1027 NULL, /* get_thread_area */
1028 NULL, /* install_fast_tracepoint_jump_pad */
1029 NULL, /* emit_ops */
1030 NULL, /* get_min_fast_tracepoint_insn_len */
1031 NULL, /* supports_range_stepping */
1032 arm_breakpoint_kind_from_current_state,
1033 arm_supports_hardware_single_step
1037 initialize_low_arch (void)
1039 /* Initialize the Linux target descriptions. */
1040 init_registers_arm ();
1041 init_registers_arm_with_iwmmxt ();
1042 init_registers_arm_with_vfpv2 ();
1043 init_registers_arm_with_vfpv3 ();
1045 initialize_low_arch_aarch32 ();
1047 initialize_regsets_info (&arm_regsets_info);