1 /* GNU/Linux/ARM specific low level interface, for the remote server for GDB.
2 Copyright (C) 1995-2018 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
,
266 target_read_memory (memaddr
, (unsigned char *) &res
, len
);
271 /* Fetch the thread-local storage pointer for libthread_db. */
274 ps_get_thread_area (struct ps_prochandle
*ph
,
275 lwpid_t lwpid
, int idx
, void **base
)
277 if (ptrace (PTRACE_GET_THREAD_AREA
, lwpid
, NULL
, base
) != 0)
280 /* IDX is the bias from the thread pointer to the beginning of the
281 thread descriptor. It has to be subtracted due to implementation
282 quirks in libthread_db. */
283 *base
= (void *) ((char *)*base
- idx
);
289 /* Query Hardware Breakpoint information for the target we are attached to
290 (using PID as ptrace argument) and set up arm_linux_hwbp_cap. */
292 arm_linux_init_hwbp_cap (int pid
)
296 if (ptrace (PTRACE_GETHBPREGS
, pid
, 0, &val
) < 0)
299 arm_linux_hwbp_cap
.arch
= (unsigned char)((val
>> 24) & 0xff);
300 if (arm_linux_hwbp_cap
.arch
== 0)
303 arm_linux_hwbp_cap
.max_wp_length
= (unsigned char)((val
>> 16) & 0xff);
304 arm_linux_hwbp_cap
.wp_count
= (unsigned char)((val
>> 8) & 0xff);
305 arm_linux_hwbp_cap
.bp_count
= (unsigned char)(val
& 0xff);
307 if (arm_linux_hwbp_cap
.wp_count
> MAX_WPTS
)
308 internal_error (__FILE__
, __LINE__
, "Unsupported number of watchpoints");
309 if (arm_linux_hwbp_cap
.bp_count
> MAX_BPTS
)
310 internal_error (__FILE__
, __LINE__
, "Unsupported number of breakpoints");
313 /* How many hardware breakpoints are available? */
315 arm_linux_get_hw_breakpoint_count (void)
317 return arm_linux_hwbp_cap
.bp_count
;
320 /* How many hardware watchpoints are available? */
322 arm_linux_get_hw_watchpoint_count (void)
324 return arm_linux_hwbp_cap
.wp_count
;
327 /* Maximum length of area watched by hardware watchpoint. */
329 arm_linux_get_hw_watchpoint_max_length (void)
331 return arm_linux_hwbp_cap
.max_wp_length
;
334 /* Initialize an ARM hardware break-/watch-point control register value.
335 BYTE_ADDRESS_SELECT is the mask of bytes to trigger on; HWBP_TYPE is the
336 type of break-/watch-point; ENABLE indicates whether the point is enabled.
338 static arm_hwbp_control_t
339 arm_hwbp_control_initialize (unsigned byte_address_select
,
340 arm_hwbp_type hwbp_type
,
343 gdb_assert ((byte_address_select
& ~0xffU
) == 0);
344 gdb_assert (hwbp_type
!= arm_hwbp_break
345 || ((byte_address_select
& 0xfU
) != 0));
347 return (byte_address_select
<< 5) | (hwbp_type
<< 3) | (3 << 1) | enable
;
350 /* Does the breakpoint control value CONTROL have the enable bit set? */
352 arm_hwbp_control_is_enabled (arm_hwbp_control_t control
)
354 return control
& 0x1;
357 /* Is the breakpoint control value CONTROL initialized? */
359 arm_hwbp_control_is_initialized (arm_hwbp_control_t control
)
364 /* Change a breakpoint control word so that it is in the disabled state. */
365 static arm_hwbp_control_t
366 arm_hwbp_control_disable (arm_hwbp_control_t control
)
368 return control
& ~0x1;
371 /* Are two break-/watch-points equal? */
373 arm_linux_hw_breakpoint_equal (const struct arm_linux_hw_breakpoint
*p1
,
374 const struct arm_linux_hw_breakpoint
*p2
)
376 return p1
->address
== p2
->address
&& p1
->control
== p2
->control
;
379 /* Convert a raw breakpoint type to an enum arm_hwbp_type. */
382 raw_bkpt_type_to_arm_hwbp_type (enum raw_bkpt_type raw_type
)
386 case raw_bkpt_type_hw
:
387 return arm_hwbp_break
;
388 case raw_bkpt_type_write_wp
:
389 return arm_hwbp_store
;
390 case raw_bkpt_type_read_wp
:
391 return arm_hwbp_load
;
392 case raw_bkpt_type_access_wp
:
393 return arm_hwbp_access
;
395 gdb_assert_not_reached ("unhandled raw type");
399 /* Initialize the hardware breakpoint structure P for a breakpoint or
400 watchpoint at ADDR to LEN. The type of watchpoint is given in TYPE.
401 Returns -1 if TYPE is unsupported, or -2 if the particular combination
402 of ADDR and LEN cannot be implemented. Otherwise, returns 0 if TYPE
403 represents a breakpoint and 1 if type represents a watchpoint. */
405 arm_linux_hw_point_initialize (enum raw_bkpt_type raw_type
, CORE_ADDR addr
,
406 int len
, struct arm_linux_hw_breakpoint
*p
)
408 arm_hwbp_type hwbp_type
;
411 hwbp_type
= raw_bkpt_type_to_arm_hwbp_type (raw_type
);
413 if (hwbp_type
== arm_hwbp_break
)
415 /* For breakpoints, the length field encodes the mode. */
418 case 2: /* 16-bit Thumb mode breakpoint */
419 case 3: /* 32-bit Thumb mode breakpoint */
423 case 4: /* 32-bit ARM mode breakpoint */
434 CORE_ADDR max_wp_length
= arm_linux_get_hw_watchpoint_max_length ();
435 CORE_ADDR aligned_addr
;
437 /* Can not set watchpoints for zero or negative lengths. */
440 /* The current ptrace interface can only handle watchpoints that are a
442 if ((len
& (len
- 1)) != 0)
445 /* Test that the range [ADDR, ADDR + LEN) fits into the largest address
446 range covered by a watchpoint. */
447 aligned_addr
= addr
& ~(max_wp_length
- 1);
448 if (aligned_addr
+ max_wp_length
< addr
+ len
)
451 mask
= (1 << len
) - 1;
454 p
->address
= (unsigned int) addr
;
455 p
->control
= arm_hwbp_control_initialize (mask
, hwbp_type
, 1);
457 return hwbp_type
!= arm_hwbp_break
;
460 /* Callback to mark a watch-/breakpoint to be updated in all threads of
461 the current process. */
464 update_registers_callback (thread_info
*thread
, int watch
, int i
)
466 struct lwp_info
*lwp
= get_thread_lwp (thread
);
468 /* The actual update is done later just before resuming the lwp,
469 we just mark that the registers need updating. */
471 lwp
->arch_private
->wpts_changed
[i
] = 1;
473 lwp
->arch_private
->bpts_changed
[i
] = 1;
475 /* If the lwp isn't stopped, force it to momentarily pause, so
476 we can update its breakpoint registers. */
478 linux_stop_lwp (lwp
);
482 arm_supports_z_point_type (char z_type
)
488 case Z_PACKET_WRITE_WP
:
489 case Z_PACKET_READ_WP
:
490 case Z_PACKET_ACCESS_WP
:
493 /* Leave the handling of sw breakpoints with the gdb client. */
498 /* Insert hardware break-/watchpoint. */
500 arm_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
501 int len
, struct raw_breakpoint
*bp
)
503 struct process_info
*proc
= current_process ();
504 struct arm_linux_hw_breakpoint p
, *pts
;
507 watch
= arm_linux_hw_point_initialize (type
, addr
, len
, &p
);
511 return watch
== -1 ? 1 : -1;
516 count
= arm_linux_get_hw_watchpoint_count ();
517 pts
= proc
->priv
->arch_private
->wpts
;
521 count
= arm_linux_get_hw_breakpoint_count ();
522 pts
= proc
->priv
->arch_private
->bpts
;
525 for (i
= 0; i
< count
; i
++)
526 if (!arm_hwbp_control_is_enabled (pts
[i
].control
))
530 /* Only update the threads of the current process. */
531 for_each_thread (current_thread
->id
.pid (), [&] (thread_info
*thread
)
533 update_registers_callback (thread
, watch
, i
);
539 /* We're out of watchpoints. */
543 /* Remove hardware break-/watchpoint. */
545 arm_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
546 int len
, struct raw_breakpoint
*bp
)
548 struct process_info
*proc
= current_process ();
549 struct arm_linux_hw_breakpoint p
, *pts
;
552 watch
= arm_linux_hw_point_initialize (type
, addr
, len
, &p
);
561 count
= arm_linux_get_hw_watchpoint_count ();
562 pts
= proc
->priv
->arch_private
->wpts
;
566 count
= arm_linux_get_hw_breakpoint_count ();
567 pts
= proc
->priv
->arch_private
->bpts
;
570 for (i
= 0; i
< count
; i
++)
571 if (arm_linux_hw_breakpoint_equal (&p
, pts
+ i
))
573 pts
[i
].control
= arm_hwbp_control_disable (pts
[i
].control
);
575 /* Only update the threads of the current process. */
576 for_each_thread (current_thread
->id
.pid (), [&] (thread_info
*thread
)
578 update_registers_callback (thread
, watch
, i
);
584 /* No watchpoint matched. */
588 /* Return whether current thread is stopped due to a watchpoint. */
590 arm_stopped_by_watchpoint (void)
592 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
595 /* We must be able to set hardware watchpoints. */
596 if (arm_linux_get_hw_watchpoint_count () == 0)
599 /* Retrieve siginfo. */
601 ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
), 0, &siginfo
);
605 /* This must be a hardware breakpoint. */
606 if (siginfo
.si_signo
!= SIGTRAP
607 || (siginfo
.si_code
& 0xffff) != 0x0004 /* TRAP_HWBKPT */)
610 /* If we are in a positive slot then we're looking at a breakpoint and not
612 if (siginfo
.si_errno
>= 0)
615 /* Cache stopped data address for use by arm_stopped_data_address. */
616 lwp
->arch_private
->stopped_data_address
617 = (CORE_ADDR
) (uintptr_t) siginfo
.si_addr
;
622 /* Return data address that triggered watchpoint. Called only if
623 arm_stopped_by_watchpoint returned true. */
625 arm_stopped_data_address (void)
627 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
628 return lwp
->arch_private
->stopped_data_address
;
631 /* Called when a new process is created. */
632 static struct arch_process_info
*
633 arm_new_process (void)
635 struct arch_process_info
*info
= XCNEW (struct arch_process_info
);
639 /* Called when a process is being deleted. */
642 arm_delete_process (struct arch_process_info
*info
)
647 /* Called when a new thread is detected. */
649 arm_new_thread (struct lwp_info
*lwp
)
651 struct arch_lwp_info
*info
= XCNEW (struct arch_lwp_info
);
654 for (i
= 0; i
< MAX_BPTS
; i
++)
655 info
->bpts_changed
[i
] = 1;
656 for (i
= 0; i
< MAX_WPTS
; i
++)
657 info
->wpts_changed
[i
] = 1;
659 lwp
->arch_private
= info
;
662 /* Function to call when a thread is being deleted. */
665 arm_delete_thread (struct arch_lwp_info
*arch_lwp
)
671 arm_new_fork (struct process_info
*parent
, struct process_info
*child
)
673 struct arch_process_info
*parent_proc_info
;
674 struct arch_process_info
*child_proc_info
;
675 struct lwp_info
*child_lwp
;
676 struct arch_lwp_info
*child_lwp_info
;
679 /* These are allocated by linux_add_process. */
680 gdb_assert (parent
->priv
!= NULL
681 && parent
->priv
->arch_private
!= NULL
);
682 gdb_assert (child
->priv
!= NULL
683 && child
->priv
->arch_private
!= NULL
);
685 parent_proc_info
= parent
->priv
->arch_private
;
686 child_proc_info
= child
->priv
->arch_private
;
688 /* Linux kernel before 2.6.33 commit
689 72f674d203cd230426437cdcf7dd6f681dad8b0d
690 will inherit hardware debug registers from parent
691 on fork/vfork/clone. Newer Linux kernels create such tasks with
692 zeroed debug registers.
694 GDB core assumes the child inherits the watchpoints/hw
695 breakpoints of the parent, and will remove them all from the
696 forked off process. Copy the debug registers mirrors into the
697 new process so that all breakpoints and watchpoints can be
698 removed together. The debug registers mirror will become zeroed
699 in the end before detaching the forked off process, thus making
700 this compatible with older Linux kernels too. */
702 *child_proc_info
= *parent_proc_info
;
704 /* Mark all the hardware breakpoints and watchpoints as changed to
705 make sure that the registers will be updated. */
706 child_lwp
= find_lwp_pid (ptid_t (child
->pid
));
707 child_lwp_info
= child_lwp
->arch_private
;
708 for (i
= 0; i
< MAX_BPTS
; i
++)
709 child_lwp_info
->bpts_changed
[i
] = 1;
710 for (i
= 0; i
< MAX_WPTS
; i
++)
711 child_lwp_info
->wpts_changed
[i
] = 1;
714 /* Called when resuming a thread.
715 If the debug regs have changed, update the thread's copies. */
717 arm_prepare_to_resume (struct lwp_info
*lwp
)
719 struct thread_info
*thread
= get_lwp_thread (lwp
);
720 int pid
= lwpid_of (thread
);
721 struct process_info
*proc
= find_process_pid (pid_of (thread
));
722 struct arch_process_info
*proc_info
= proc
->priv
->arch_private
;
723 struct arch_lwp_info
*lwp_info
= lwp
->arch_private
;
726 for (i
= 0; i
< arm_linux_get_hw_breakpoint_count (); i
++)
727 if (lwp_info
->bpts_changed
[i
])
731 if (arm_hwbp_control_is_enabled (proc_info
->bpts
[i
].control
))
732 if (ptrace (PTRACE_SETHBPREGS
, pid
,
733 (PTRACE_TYPE_ARG3
) ((i
<< 1) + 1),
734 &proc_info
->bpts
[i
].address
) < 0)
735 perror_with_name ("Unexpected error setting breakpoint address");
737 if (arm_hwbp_control_is_initialized (proc_info
->bpts
[i
].control
))
738 if (ptrace (PTRACE_SETHBPREGS
, pid
,
739 (PTRACE_TYPE_ARG3
) ((i
<< 1) + 2),
740 &proc_info
->bpts
[i
].control
) < 0)
741 perror_with_name ("Unexpected error setting breakpoint");
743 lwp_info
->bpts_changed
[i
] = 0;
746 for (i
= 0; i
< arm_linux_get_hw_watchpoint_count (); i
++)
747 if (lwp_info
->wpts_changed
[i
])
751 if (arm_hwbp_control_is_enabled (proc_info
->wpts
[i
].control
))
752 if (ptrace (PTRACE_SETHBPREGS
, pid
,
753 (PTRACE_TYPE_ARG3
) -((i
<< 1) + 1),
754 &proc_info
->wpts
[i
].address
) < 0)
755 perror_with_name ("Unexpected error setting watchpoint address");
757 if (arm_hwbp_control_is_initialized (proc_info
->wpts
[i
].control
))
758 if (ptrace (PTRACE_SETHBPREGS
, pid
,
759 (PTRACE_TYPE_ARG3
) -((i
<< 1) + 2),
760 &proc_info
->wpts
[i
].control
) < 0)
761 perror_with_name ("Unexpected error setting watchpoint");
763 lwp_info
->wpts_changed
[i
] = 0;
767 /* Find the next pc for a sigreturn or rt_sigreturn syscall. In
768 addition, set IS_THUMB depending on whether we will return to ARM
770 See arm-linux.h for stack layout details. */
772 arm_sigreturn_next_pc (struct regcache
*regcache
, int svc_number
,
776 unsigned long sp_data
;
777 /* Offset of PC register. */
779 CORE_ADDR next_pc
= 0;
782 gdb_assert (svc_number
== __NR_sigreturn
|| svc_number
== __NR_rt_sigreturn
);
784 collect_register_by_name (regcache
, "sp", &sp
);
785 (*the_target
->read_memory
) (sp
, (unsigned char *) &sp_data
, 4);
787 pc_offset
= arm_linux_sigreturn_next_pc_offset
788 (sp
, sp_data
, svc_number
, __NR_sigreturn
== svc_number
? 1 : 0);
790 (*the_target
->read_memory
) (sp
+ pc_offset
, (unsigned char *) &next_pc
, 4);
792 /* Set IS_THUMB according the CPSR saved on the stack. */
793 (*the_target
->read_memory
) (sp
+ pc_offset
+ 4, (unsigned char *) &cpsr
, 4);
794 *is_thumb
= ((cpsr
& CPSR_T
) != 0);
799 /* When PC is at a syscall instruction, return the PC of the next
800 instruction to be executed. */
802 get_next_pcs_syscall_next_pc (struct arm_get_next_pcs
*self
)
804 CORE_ADDR next_pc
= 0;
805 CORE_ADDR pc
= regcache_read_pc (self
->regcache
);
806 int is_thumb
= arm_is_thumb_mode ();
807 ULONGEST svc_number
= 0;
808 struct regcache
*regcache
= self
->regcache
;
812 collect_register (regcache
, 7, &svc_number
);
817 unsigned long this_instr
;
818 unsigned long svc_operand
;
820 target_read_memory (pc
, (unsigned char *) &this_instr
, 4);
821 svc_operand
= (0x00ffffff & this_instr
);
823 if (svc_operand
) /* OABI. */
825 svc_number
= svc_operand
- 0x900000;
829 collect_register (regcache
, 7, &svc_number
);
835 /* This is a sigreturn or sigreturn_rt syscall. */
836 if (svc_number
== __NR_sigreturn
|| svc_number
== __NR_rt_sigreturn
)
838 /* SIGRETURN or RT_SIGRETURN may affect the arm thumb mode, so
840 next_pc
= arm_sigreturn_next_pc (regcache
, svc_number
, &is_thumb
);
843 /* Addresses for calling Thumb functions have the bit 0 set. */
845 next_pc
= MAKE_THUMB_ADDR (next_pc
);
851 arm_get_hwcap (unsigned long *valp
)
853 unsigned char *data
= (unsigned char *) alloca (8);
856 while ((*the_target
->read_auxv
) (offset
, data
, 8) == 8)
858 unsigned int *data_p
= (unsigned int *)data
;
859 if (data_p
[0] == AT_HWCAP
)
872 static const struct target_desc
*
873 arm_read_description (void)
875 int pid
= lwpid_of (current_thread
);
876 unsigned long arm_hwcap
= 0;
878 /* Query hardware watchpoint/breakpoint capabilities. */
879 arm_linux_init_hwbp_cap (pid
);
881 if (arm_get_hwcap (&arm_hwcap
) == 0)
884 if (arm_hwcap
& HWCAP_IWMMXT
)
885 return tdesc_arm_with_iwmmxt
;
887 if (arm_hwcap
& HWCAP_VFP
)
889 const struct target_desc
*result
;
892 /* NEON implies either no VFP, or VFPv3-D32. We only support
894 if (arm_hwcap
& HWCAP_NEON
)
895 result
= tdesc_arm_with_neon
;
896 else if ((arm_hwcap
& (HWCAP_VFPv3
| HWCAP_VFPv3D16
)) == HWCAP_VFPv3
)
897 result
= tdesc_arm_with_vfpv3
;
899 result
= tdesc_arm_with_vfpv2
;
901 /* Now make sure that the kernel supports reading these
902 registers. Support was added in 2.6.30. */
904 buf
= (char *) xmalloc (32 * 8 + 4);
905 if (ptrace (PTRACE_GETVFPREGS
, pid
, 0, buf
) < 0
914 /* The default configuration uses legacy FPA registers, probably
920 arm_arch_setup (void)
922 int tid
= lwpid_of (current_thread
);
926 current_process ()->tdesc
= arm_read_description ();
928 iov
.iov_base
= gpregs
;
929 iov
.iov_len
= sizeof (gpregs
);
931 /* Check if PTRACE_GETREGSET works. */
932 if (ptrace (PTRACE_GETREGSET
, tid
, NT_PRSTATUS
, &iov
) == 0)
933 have_ptrace_getregset
= 1;
935 have_ptrace_getregset
= 0;
938 /* Fetch the next possible PCs after the current instruction executes. */
940 static std::vector
<CORE_ADDR
>
941 arm_gdbserver_get_next_pcs (struct regcache
*regcache
)
943 struct arm_get_next_pcs next_pcs_ctx
;
945 arm_get_next_pcs_ctor (&next_pcs_ctx
,
947 /* Byte order is ignored assumed as host. */
953 return arm_get_next_pcs (&next_pcs_ctx
);
956 /* Support for hardware single step. */
959 arm_supports_hardware_single_step (void)
964 /* Implementation of linux_target_ops method "get_syscall_trapinfo". */
967 arm_get_syscall_trapinfo (struct regcache
*regcache
, int *sysno
)
969 if (arm_is_thumb_mode ())
970 collect_register_by_name (regcache
, "r7", sysno
);
976 collect_register_by_name (regcache
, "pc", &pc
);
978 if ((*the_target
->read_memory
) (pc
- 4, (unsigned char *) &insn
, 4))
979 *sysno
= UNKNOWN_SYSCALL
;
982 unsigned long svc_operand
= (0x00ffffff & insn
);
987 *sysno
= svc_operand
- 0x900000;
992 collect_register_by_name (regcache
, "r7", sysno
);
998 /* Register sets without using PTRACE_GETREGSET. */
1000 static struct regset_info arm_regsets
[] = {
1001 { PTRACE_GETREGS
, PTRACE_SETREGS
, 0, 18 * 4,
1003 arm_fill_gregset
, arm_store_gregset
},
1004 { PTRACE_GETWMMXREGS
, PTRACE_SETWMMXREGS
, 0, 16 * 8 + 6 * 4,
1006 arm_fill_wmmxregset
, arm_store_wmmxregset
},
1007 { PTRACE_GETVFPREGS
, PTRACE_SETVFPREGS
, 0, 32 * 8 + 4,
1009 arm_fill_vfpregset
, arm_store_vfpregset
},
1013 static struct regsets_info arm_regsets_info
=
1015 arm_regsets
, /* regsets */
1016 0, /* num_regsets */
1017 NULL
, /* disabled_regsets */
1020 static struct usrregs_info arm_usrregs_info
=
1026 static struct regs_info regs_info_arm
=
1028 NULL
, /* regset_bitmap */
1033 static const struct regs_info
*
1034 arm_regs_info (void)
1036 const struct target_desc
*tdesc
= current_process ()->tdesc
;
1038 if (have_ptrace_getregset
== 1
1039 && (tdesc
== tdesc_arm_with_neon
|| tdesc
== tdesc_arm_with_vfpv3
))
1040 return ®s_info_aarch32
;
1042 return ®s_info_arm
;
1045 struct linux_target_ops the_low_target
= {
1048 arm_cannot_fetch_register
,
1049 arm_cannot_store_register
,
1050 NULL
, /* fetch_register */
1053 arm_breakpoint_kind_from_pc
,
1054 arm_sw_breakpoint_from_kind
,
1055 arm_gdbserver_get_next_pcs
,
1058 arm_supports_z_point_type
,
1061 arm_stopped_by_watchpoint
,
1062 arm_stopped_data_address
,
1063 NULL
, /* collect_ptrace_register */
1064 NULL
, /* supply_ptrace_register */
1065 NULL
, /* siginfo_fixup */
1071 arm_prepare_to_resume
,
1072 NULL
, /* process_qsupported */
1073 NULL
, /* supports_tracepoints */
1074 NULL
, /* get_thread_area */
1075 NULL
, /* install_fast_tracepoint_jump_pad */
1076 NULL
, /* emit_ops */
1077 NULL
, /* get_min_fast_tracepoint_insn_len */
1078 NULL
, /* supports_range_stepping */
1079 arm_breakpoint_kind_from_current_state
,
1080 arm_supports_hardware_single_step
,
1081 arm_get_syscall_trapinfo
,
1085 initialize_low_arch (void)
1087 /* Initialize the Linux target descriptions. */
1088 init_registers_arm ();
1089 init_registers_arm_with_iwmmxt ();
1090 init_registers_arm_with_vfpv2 ();
1091 init_registers_arm_with_vfpv3 ();
1093 initialize_low_arch_aarch32 ();
1095 initialize_regsets_info (&arm_regsets_info
);