1 /* GNU/Linux/ARM specific low level interface, for the remote server for GDB.
2 Copyright (C) 1995-2019 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)
178 if (regcache->tdesc != tdesc_arm_with_iwmmxt)
181 for (int i = 0; i < 16; i++)
182 collect_register (regcache, arm_num_regs + i, (char *) buf + i * 8);
184 /* We only have access to wcssf, wcasf, and wcgr0-wcgr3. */
185 for (int i = 0; i < 6; i++)
186 collect_register (regcache, arm_num_regs + i + 16,
187 (char *) buf + 16 * 8 + i * 4);
191 arm_store_wmmxregset (struct regcache *regcache, const void *buf)
193 if (regcache->tdesc != tdesc_arm_with_iwmmxt)
196 for (int i = 0; i < 16; i++)
197 supply_register (regcache, arm_num_regs + i, (char *) buf + i * 8);
199 /* We only have access to wcssf, wcasf, and wcgr0-wcgr3. */
200 for (int i = 0; i < 6; i++)
201 supply_register (regcache, arm_num_regs + i + 16,
202 (char *) buf + 16 * 8 + i * 4);
206 arm_fill_vfpregset (struct regcache *regcache, void *buf)
210 if (regcache->tdesc == tdesc_arm_with_neon
211 || regcache->tdesc == tdesc_arm_with_vfpv3)
213 else if (regcache->tdesc == tdesc_arm_with_vfpv2)
218 arm_fill_vfpregset_num (regcache, buf, num);
221 /* Wrapper of UNMAKE_THUMB_ADDR for get_next_pcs. */
223 get_next_pcs_addr_bits_remove (struct arm_get_next_pcs *self, CORE_ADDR val)
225 return UNMAKE_THUMB_ADDR (val);
229 arm_store_vfpregset (struct regcache *regcache, const void *buf)
233 if (regcache->tdesc == tdesc_arm_with_neon
234 || regcache->tdesc == tdesc_arm_with_vfpv3)
236 else if (regcache->tdesc == tdesc_arm_with_vfpv2)
241 arm_store_vfpregset_num (regcache, buf, num);
244 /* Wrapper of arm_is_thumb_mode for get_next_pcs. */
246 get_next_pcs_is_thumb (struct arm_get_next_pcs *self)
248 return arm_is_thumb_mode ();
251 /* Read memory from the inferiror.
252 BYTE_ORDER is ignored and there to keep compatiblity with GDB's
253 read_memory_unsigned_integer. */
255 get_next_pcs_read_memory_unsigned_integer (CORE_ADDR memaddr,
262 target_read_memory (memaddr, (unsigned char *) &res, len);
267 /* Fetch the thread-local storage pointer for libthread_db. */
270 ps_get_thread_area (struct ps_prochandle *ph,
271 lwpid_t lwpid, int idx, void **base)
273 if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
276 /* IDX is the bias from the thread pointer to the beginning of the
277 thread descriptor. It has to be subtracted due to implementation
278 quirks in libthread_db. */
279 *base = (void *) ((char *)*base - idx);
285 /* Query Hardware Breakpoint information for the target we are attached to
286 (using PID as ptrace argument) and set up arm_linux_hwbp_cap. */
288 arm_linux_init_hwbp_cap (int pid)
292 if (ptrace (PTRACE_GETHBPREGS, pid, 0, &val) < 0)
295 arm_linux_hwbp_cap.arch = (unsigned char)((val >> 24) & 0xff);
296 if (arm_linux_hwbp_cap.arch == 0)
299 arm_linux_hwbp_cap.max_wp_length = (unsigned char)((val >> 16) & 0xff);
300 arm_linux_hwbp_cap.wp_count = (unsigned char)((val >> 8) & 0xff);
301 arm_linux_hwbp_cap.bp_count = (unsigned char)(val & 0xff);
303 if (arm_linux_hwbp_cap.wp_count > MAX_WPTS)
304 internal_error (__FILE__, __LINE__, "Unsupported number of watchpoints");
305 if (arm_linux_hwbp_cap.bp_count > MAX_BPTS)
306 internal_error (__FILE__, __LINE__, "Unsupported number of breakpoints");
309 /* How many hardware breakpoints are available? */
311 arm_linux_get_hw_breakpoint_count (void)
313 return arm_linux_hwbp_cap.bp_count;
316 /* How many hardware watchpoints are available? */
318 arm_linux_get_hw_watchpoint_count (void)
320 return arm_linux_hwbp_cap.wp_count;
323 /* Maximum length of area watched by hardware watchpoint. */
325 arm_linux_get_hw_watchpoint_max_length (void)
327 return arm_linux_hwbp_cap.max_wp_length;
330 /* Initialize an ARM hardware break-/watch-point control register value.
331 BYTE_ADDRESS_SELECT is the mask of bytes to trigger on; HWBP_TYPE is the
332 type of break-/watch-point; ENABLE indicates whether the point is enabled.
334 static arm_hwbp_control_t
335 arm_hwbp_control_initialize (unsigned byte_address_select,
336 arm_hwbp_type hwbp_type,
339 gdb_assert ((byte_address_select & ~0xffU) == 0);
340 gdb_assert (hwbp_type != arm_hwbp_break
341 || ((byte_address_select & 0xfU) != 0));
343 return (byte_address_select << 5) | (hwbp_type << 3) | (3 << 1) | enable;
346 /* Does the breakpoint control value CONTROL have the enable bit set? */
348 arm_hwbp_control_is_enabled (arm_hwbp_control_t control)
350 return control & 0x1;
353 /* Is the breakpoint control value CONTROL initialized? */
355 arm_hwbp_control_is_initialized (arm_hwbp_control_t control)
360 /* Change a breakpoint control word so that it is in the disabled state. */
361 static arm_hwbp_control_t
362 arm_hwbp_control_disable (arm_hwbp_control_t control)
364 return control & ~0x1;
367 /* Are two break-/watch-points equal? */
369 arm_linux_hw_breakpoint_equal (const struct arm_linux_hw_breakpoint *p1,
370 const struct arm_linux_hw_breakpoint *p2)
372 return p1->address == p2->address && p1->control == p2->control;
375 /* Convert a raw breakpoint type to an enum arm_hwbp_type. */
378 raw_bkpt_type_to_arm_hwbp_type (enum raw_bkpt_type raw_type)
382 case raw_bkpt_type_hw:
383 return arm_hwbp_break;
384 case raw_bkpt_type_write_wp:
385 return arm_hwbp_store;
386 case raw_bkpt_type_read_wp:
387 return arm_hwbp_load;
388 case raw_bkpt_type_access_wp:
389 return arm_hwbp_access;
391 gdb_assert_not_reached ("unhandled raw type");
395 /* Initialize the hardware breakpoint structure P for a breakpoint or
396 watchpoint at ADDR to LEN. The type of watchpoint is given in TYPE.
397 Returns -1 if TYPE is unsupported, or -2 if the particular combination
398 of ADDR and LEN cannot be implemented. Otherwise, returns 0 if TYPE
399 represents a breakpoint and 1 if type represents a watchpoint. */
401 arm_linux_hw_point_initialize (enum raw_bkpt_type raw_type, CORE_ADDR addr,
402 int len, struct arm_linux_hw_breakpoint *p)
404 arm_hwbp_type hwbp_type;
407 hwbp_type = raw_bkpt_type_to_arm_hwbp_type (raw_type);
409 if (hwbp_type == arm_hwbp_break)
411 /* For breakpoints, the length field encodes the mode. */
414 case 2: /* 16-bit Thumb mode breakpoint */
415 case 3: /* 32-bit Thumb mode breakpoint */
419 case 4: /* 32-bit ARM mode breakpoint */
430 CORE_ADDR max_wp_length = arm_linux_get_hw_watchpoint_max_length ();
431 CORE_ADDR aligned_addr;
433 /* Can not set watchpoints for zero or negative lengths. */
436 /* The current ptrace interface can only handle watchpoints that are a
438 if ((len & (len - 1)) != 0)
441 /* Test that the range [ADDR, ADDR + LEN) fits into the largest address
442 range covered by a watchpoint. */
443 aligned_addr = addr & ~(max_wp_length - 1);
444 if (aligned_addr + max_wp_length < addr + len)
447 mask = (1 << len) - 1;
450 p->address = (unsigned int) addr;
451 p->control = arm_hwbp_control_initialize (mask, hwbp_type, 1);
453 return hwbp_type != arm_hwbp_break;
456 /* Callback to mark a watch-/breakpoint to be updated in all threads of
457 the current process. */
460 update_registers_callback (thread_info *thread, int watch, int i)
462 struct lwp_info *lwp = get_thread_lwp (thread);
464 /* The actual update is done later just before resuming the lwp,
465 we just mark that the registers need updating. */
467 lwp->arch_private->wpts_changed[i] = 1;
469 lwp->arch_private->bpts_changed[i] = 1;
471 /* If the lwp isn't stopped, force it to momentarily pause, so
472 we can update its breakpoint registers. */
474 linux_stop_lwp (lwp);
478 arm_supports_z_point_type (char z_type)
484 case Z_PACKET_WRITE_WP:
485 case Z_PACKET_READ_WP:
486 case Z_PACKET_ACCESS_WP:
489 /* Leave the handling of sw breakpoints with the gdb client. */
494 /* Insert hardware break-/watchpoint. */
496 arm_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
497 int len, struct raw_breakpoint *bp)
499 struct process_info *proc = current_process ();
500 struct arm_linux_hw_breakpoint p, *pts;
503 watch = arm_linux_hw_point_initialize (type, addr, len, &p);
507 return watch == -1 ? 1 : -1;
512 count = arm_linux_get_hw_watchpoint_count ();
513 pts = proc->priv->arch_private->wpts;
517 count = arm_linux_get_hw_breakpoint_count ();
518 pts = proc->priv->arch_private->bpts;
521 for (i = 0; i < count; i++)
522 if (!arm_hwbp_control_is_enabled (pts[i].control))
526 /* Only update the threads of the current process. */
527 for_each_thread (current_thread->id.pid (), [&] (thread_info *thread)
529 update_registers_callback (thread, watch, i);
535 /* We're out of watchpoints. */
539 /* Remove hardware break-/watchpoint. */
541 arm_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
542 int len, struct raw_breakpoint *bp)
544 struct process_info *proc = current_process ();
545 struct arm_linux_hw_breakpoint p, *pts;
548 watch = arm_linux_hw_point_initialize (type, addr, len, &p);
557 count = arm_linux_get_hw_watchpoint_count ();
558 pts = proc->priv->arch_private->wpts;
562 count = arm_linux_get_hw_breakpoint_count ();
563 pts = proc->priv->arch_private->bpts;
566 for (i = 0; i < count; i++)
567 if (arm_linux_hw_breakpoint_equal (&p, pts + i))
569 pts[i].control = arm_hwbp_control_disable (pts[i].control);
571 /* Only update the threads of the current process. */
572 for_each_thread (current_thread->id.pid (), [&] (thread_info *thread)
574 update_registers_callback (thread, watch, i);
580 /* No watchpoint matched. */
584 /* Return whether current thread is stopped due to a watchpoint. */
586 arm_stopped_by_watchpoint (void)
588 struct lwp_info *lwp = get_thread_lwp (current_thread);
591 /* We must be able to set hardware watchpoints. */
592 if (arm_linux_get_hw_watchpoint_count () == 0)
595 /* Retrieve siginfo. */
597 ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread), 0, &siginfo);
601 /* This must be a hardware breakpoint. */
602 if (siginfo.si_signo != SIGTRAP
603 || (siginfo.si_code & 0xffff) != 0x0004 /* TRAP_HWBKPT */)
606 /* If we are in a positive slot then we're looking at a breakpoint and not
608 if (siginfo.si_errno >= 0)
611 /* Cache stopped data address for use by arm_stopped_data_address. */
612 lwp->arch_private->stopped_data_address
613 = (CORE_ADDR) (uintptr_t) siginfo.si_addr;
618 /* Return data address that triggered watchpoint. Called only if
619 arm_stopped_by_watchpoint returned true. */
621 arm_stopped_data_address (void)
623 struct lwp_info *lwp = get_thread_lwp (current_thread);
624 return lwp->arch_private->stopped_data_address;
627 /* Called when a new process is created. */
628 static struct arch_process_info *
629 arm_new_process (void)
631 struct arch_process_info *info = XCNEW (struct arch_process_info);
635 /* Called when a process is being deleted. */
638 arm_delete_process (struct arch_process_info *info)
643 /* Called when a new thread is detected. */
645 arm_new_thread (struct lwp_info *lwp)
647 struct arch_lwp_info *info = XCNEW (struct arch_lwp_info);
650 for (i = 0; i < MAX_BPTS; i++)
651 info->bpts_changed[i] = 1;
652 for (i = 0; i < MAX_WPTS; i++)
653 info->wpts_changed[i] = 1;
655 lwp->arch_private = info;
658 /* Function to call when a thread is being deleted. */
661 arm_delete_thread (struct arch_lwp_info *arch_lwp)
667 arm_new_fork (struct process_info *parent, struct process_info *child)
669 struct arch_process_info *parent_proc_info;
670 struct arch_process_info *child_proc_info;
671 struct lwp_info *child_lwp;
672 struct arch_lwp_info *child_lwp_info;
675 /* These are allocated by linux_add_process. */
676 gdb_assert (parent->priv != NULL
677 && parent->priv->arch_private != NULL);
678 gdb_assert (child->priv != NULL
679 && child->priv->arch_private != NULL);
681 parent_proc_info = parent->priv->arch_private;
682 child_proc_info = child->priv->arch_private;
684 /* Linux kernel before 2.6.33 commit
685 72f674d203cd230426437cdcf7dd6f681dad8b0d
686 will inherit hardware debug registers from parent
687 on fork/vfork/clone. Newer Linux kernels create such tasks with
688 zeroed debug registers.
690 GDB core assumes the child inherits the watchpoints/hw
691 breakpoints of the parent, and will remove them all from the
692 forked off process. Copy the debug registers mirrors into the
693 new process so that all breakpoints and watchpoints can be
694 removed together. The debug registers mirror will become zeroed
695 in the end before detaching the forked off process, thus making
696 this compatible with older Linux kernels too. */
698 *child_proc_info = *parent_proc_info;
700 /* Mark all the hardware breakpoints and watchpoints as changed to
701 make sure that the registers will be updated. */
702 child_lwp = find_lwp_pid (ptid_t (child->pid));
703 child_lwp_info = child_lwp->arch_private;
704 for (i = 0; i < MAX_BPTS; i++)
705 child_lwp_info->bpts_changed[i] = 1;
706 for (i = 0; i < MAX_WPTS; i++)
707 child_lwp_info->wpts_changed[i] = 1;
710 /* Called when resuming a thread.
711 If the debug regs have changed, update the thread's copies. */
713 arm_prepare_to_resume (struct lwp_info *lwp)
715 struct thread_info *thread = get_lwp_thread (lwp);
716 int pid = lwpid_of (thread);
717 struct process_info *proc = find_process_pid (pid_of (thread));
718 struct arch_process_info *proc_info = proc->priv->arch_private;
719 struct arch_lwp_info *lwp_info = lwp->arch_private;
722 for (i = 0; i < arm_linux_get_hw_breakpoint_count (); i++)
723 if (lwp_info->bpts_changed[i])
727 if (arm_hwbp_control_is_enabled (proc_info->bpts[i].control))
728 if (ptrace (PTRACE_SETHBPREGS, pid,
729 (PTRACE_TYPE_ARG3) ((i << 1) + 1),
730 &proc_info->bpts[i].address) < 0)
731 perror_with_name ("Unexpected error setting breakpoint address");
733 if (arm_hwbp_control_is_initialized (proc_info->bpts[i].control))
734 if (ptrace (PTRACE_SETHBPREGS, pid,
735 (PTRACE_TYPE_ARG3) ((i << 1) + 2),
736 &proc_info->bpts[i].control) < 0)
737 perror_with_name ("Unexpected error setting breakpoint");
739 lwp_info->bpts_changed[i] = 0;
742 for (i = 0; i < arm_linux_get_hw_watchpoint_count (); i++)
743 if (lwp_info->wpts_changed[i])
747 if (arm_hwbp_control_is_enabled (proc_info->wpts[i].control))
748 if (ptrace (PTRACE_SETHBPREGS, pid,
749 (PTRACE_TYPE_ARG3) -((i << 1) + 1),
750 &proc_info->wpts[i].address) < 0)
751 perror_with_name ("Unexpected error setting watchpoint address");
753 if (arm_hwbp_control_is_initialized (proc_info->wpts[i].control))
754 if (ptrace (PTRACE_SETHBPREGS, pid,
755 (PTRACE_TYPE_ARG3) -((i << 1) + 2),
756 &proc_info->wpts[i].control) < 0)
757 perror_with_name ("Unexpected error setting watchpoint");
759 lwp_info->wpts_changed[i] = 0;
763 /* Find the next pc for a sigreturn or rt_sigreturn syscall. In
764 addition, set IS_THUMB depending on whether we will return to ARM
766 See arm-linux.h for stack layout details. */
768 arm_sigreturn_next_pc (struct regcache *regcache, int svc_number,
772 unsigned long sp_data;
773 /* Offset of PC register. */
775 CORE_ADDR next_pc = 0;
778 gdb_assert (svc_number == __NR_sigreturn || svc_number == __NR_rt_sigreturn);
780 collect_register_by_name (regcache, "sp", &sp);
781 (*the_target->read_memory) (sp, (unsigned char *) &sp_data, 4);
783 pc_offset = arm_linux_sigreturn_next_pc_offset
784 (sp, sp_data, svc_number, __NR_sigreturn == svc_number ? 1 : 0);
786 (*the_target->read_memory) (sp + pc_offset, (unsigned char *) &next_pc, 4);
788 /* Set IS_THUMB according the CPSR saved on the stack. */
789 (*the_target->read_memory) (sp + pc_offset + 4, (unsigned char *) &cpsr, 4);
790 *is_thumb = ((cpsr & CPSR_T) != 0);
795 /* When PC is at a syscall instruction, return the PC of the next
796 instruction to be executed. */
798 get_next_pcs_syscall_next_pc (struct arm_get_next_pcs *self)
800 CORE_ADDR next_pc = 0;
801 CORE_ADDR pc = regcache_read_pc (self->regcache);
802 int is_thumb = arm_is_thumb_mode ();
803 ULONGEST svc_number = 0;
804 struct regcache *regcache = self->regcache;
808 collect_register (regcache, 7, &svc_number);
813 unsigned long this_instr;
814 unsigned long svc_operand;
816 target_read_memory (pc, (unsigned char *) &this_instr, 4);
817 svc_operand = (0x00ffffff & this_instr);
819 if (svc_operand) /* OABI. */
821 svc_number = svc_operand - 0x900000;
825 collect_register (regcache, 7, &svc_number);
831 /* This is a sigreturn or sigreturn_rt syscall. */
832 if (svc_number == __NR_sigreturn || svc_number == __NR_rt_sigreturn)
834 /* SIGRETURN or RT_SIGRETURN may affect the arm thumb mode, so
836 next_pc = arm_sigreturn_next_pc (regcache, svc_number, &is_thumb);
839 /* Addresses for calling Thumb functions have the bit 0 set. */
841 next_pc = MAKE_THUMB_ADDR (next_pc);
846 static const struct target_desc *
847 arm_read_description (void)
849 unsigned long arm_hwcap = linux_get_hwcap (4);
851 if (arm_hwcap & HWCAP_IWMMXT)
852 return tdesc_arm_with_iwmmxt;
854 if (arm_hwcap & HWCAP_VFP)
856 /* Make sure that the kernel supports reading VFP registers. Support was
858 int pid = lwpid_of (current_thread);
860 char *buf = (char *) alloca (ARM_VFP3_REGS_SIZE);
861 if (ptrace (PTRACE_GETVFPREGS, pid, 0, buf) < 0 && errno == EIO)
864 /* NEON implies either no VFP, or VFPv3-D32. We only support
866 if (arm_hwcap & HWCAP_NEON)
867 return tdesc_arm_with_neon;
868 else if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPv3D16)) == HWCAP_VFPv3)
869 return tdesc_arm_with_vfpv3;
871 return tdesc_arm_with_vfpv2;
874 /* The default configuration uses legacy FPA registers, probably
880 arm_arch_setup (void)
882 int tid = lwpid_of (current_thread);
886 /* Query hardware watchpoint/breakpoint capabilities. */
887 arm_linux_init_hwbp_cap (tid);
889 current_process ()->tdesc = arm_read_description ();
891 iov.iov_base = gpregs;
892 iov.iov_len = sizeof (gpregs);
894 /* Check if PTRACE_GETREGSET works. */
895 if (ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iov) == 0)
896 have_ptrace_getregset = 1;
898 have_ptrace_getregset = 0;
901 /* Fetch the next possible PCs after the current instruction executes. */
903 static std::vector<CORE_ADDR>
904 arm_gdbserver_get_next_pcs (struct regcache *regcache)
906 struct arm_get_next_pcs next_pcs_ctx;
908 arm_get_next_pcs_ctor (&next_pcs_ctx,
910 /* Byte order is ignored assumed as host. */
916 return arm_get_next_pcs (&next_pcs_ctx);
919 /* Support for hardware single step. */
922 arm_supports_hardware_single_step (void)
927 /* Implementation of linux_target_ops method "get_syscall_trapinfo". */
930 arm_get_syscall_trapinfo (struct regcache *regcache, int *sysno)
932 if (arm_is_thumb_mode ())
933 collect_register_by_name (regcache, "r7", sysno);
939 collect_register_by_name (regcache, "pc", &pc);
941 if ((*the_target->read_memory) (pc - 4, (unsigned char *) &insn, 4))
942 *sysno = UNKNOWN_SYSCALL;
945 unsigned long svc_operand = (0x00ffffff & insn);
950 *sysno = svc_operand - 0x900000;
955 collect_register_by_name (regcache, "r7", sysno);
961 /* Register sets without using PTRACE_GETREGSET. */
963 static struct regset_info arm_regsets[] = {
964 { PTRACE_GETREGS, PTRACE_SETREGS, 0,
965 ARM_CORE_REGS_SIZE + ARM_INT_REGISTER_SIZE, GENERAL_REGS,
966 arm_fill_gregset, arm_store_gregset },
967 { PTRACE_GETWMMXREGS, PTRACE_SETWMMXREGS, 0, IWMMXT_REGS_SIZE, EXTENDED_REGS,
968 arm_fill_wmmxregset, arm_store_wmmxregset },
969 { PTRACE_GETVFPREGS, PTRACE_SETVFPREGS, 0, ARM_VFP3_REGS_SIZE, EXTENDED_REGS,
970 arm_fill_vfpregset, arm_store_vfpregset },
974 static struct regsets_info arm_regsets_info =
976 arm_regsets, /* regsets */
978 NULL, /* disabled_regsets */
981 static struct usrregs_info arm_usrregs_info =
987 static struct regs_info regs_info_arm =
989 NULL, /* regset_bitmap */
994 static const struct regs_info *
997 const struct target_desc *tdesc = current_process ()->tdesc;
999 if (have_ptrace_getregset == 1
1000 && (tdesc == tdesc_arm_with_neon || tdesc == tdesc_arm_with_vfpv3))
1001 return ®s_info_aarch32;
1003 return ®s_info_arm;
1006 struct linux_target_ops the_low_target = {
1009 arm_cannot_fetch_register,
1010 arm_cannot_store_register,
1011 NULL, /* fetch_register */
1014 arm_breakpoint_kind_from_pc,
1015 arm_sw_breakpoint_from_kind,
1016 arm_gdbserver_get_next_pcs,
1019 arm_supports_z_point_type,
1022 arm_stopped_by_watchpoint,
1023 arm_stopped_data_address,
1024 NULL, /* collect_ptrace_register */
1025 NULL, /* supply_ptrace_register */
1026 NULL, /* siginfo_fixup */
1032 arm_prepare_to_resume,
1033 NULL, /* process_qsupported */
1034 NULL, /* supports_tracepoints */
1035 NULL, /* get_thread_area */
1036 NULL, /* install_fast_tracepoint_jump_pad */
1037 NULL, /* emit_ops */
1038 NULL, /* get_min_fast_tracepoint_insn_len */
1039 NULL, /* supports_range_stepping */
1040 arm_breakpoint_kind_from_current_state,
1041 arm_supports_hardware_single_step,
1042 arm_get_syscall_trapinfo,
1046 initialize_low_arch (void)
1048 /* Initialize the Linux target descriptions. */
1049 init_registers_arm ();
1050 init_registers_arm_with_iwmmxt ();
1051 init_registers_arm_with_vfpv2 ();
1052 init_registers_arm_with_vfpv3 ();
1054 initialize_low_arch_aarch32 ();
1056 initialize_regsets_info (&arm_regsets_info);