1 /* Target-dependent code for Atmel AVR, for GDB.
3 Copyright (C) 1996-2018 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 /* Contributed by Theodore A. Roth, troth@openavr.org */
22 /* Portions of this file were taken from the original gdb-4.18 patch developed
23 by Denis Chertykov, denisc@overta.ru */
27 #include "frame-unwind.h"
28 #include "frame-base.h"
29 #include "trad-frame.h"
35 #include "arch-utils.h"
43 (AVR micros are pure Harvard Architecture processors.)
45 The AVR family of microcontrollers have three distinctly different memory
46 spaces: flash, sram and eeprom. The flash is 16 bits wide and is used for
47 the most part to store program instructions. The sram is 8 bits wide and is
48 used for the stack and the heap. Some devices lack sram and some can have
49 an additional external sram added on as a peripheral.
51 The eeprom is 8 bits wide and is used to store data when the device is
52 powered down. Eeprom is not directly accessible, it can only be accessed
53 via io-registers using a special algorithm. Accessing eeprom via gdb's
54 remote serial protocol ('m' or 'M' packets) looks difficult to do and is
55 not included at this time.
57 [The eeprom could be read manually via ``x/b <eaddr + AVR_EMEM_START>'' or
58 written using ``set {unsigned char}<eaddr + AVR_EMEM_START>''. For this to
59 work, the remote target must be able to handle eeprom accesses and perform
60 the address translation.]
62 All three memory spaces have physical addresses beginning at 0x0. In
63 addition, the flash is addressed by gcc/binutils/gdb with respect to 8 bit
64 bytes instead of the 16 bit wide words used by the real device for the
67 In order for remote targets to work correctly, extra bits must be added to
68 addresses before they are send to the target or received from the target
69 via the remote serial protocol. The extra bits are the MSBs and are used to
70 decode which memory space the address is referring to. */
72 /* Constants: prefixed with AVR_ to avoid name space clashes */
74 /* Address space flags */
76 /* We are assigning the TYPE_INSTANCE_FLAG_ADDRESS_CLASS_1 to the flash address
79 #define AVR_TYPE_ADDRESS_CLASS_FLASH TYPE_ADDRESS_CLASS_1
80 #define AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH \
81 TYPE_INSTANCE_FLAG_ADDRESS_CLASS_1
96 AVR_NUM_REGS = 32 + 1 /*SREG*/ + 1 /*SP*/ + 1 /*PC*/,
97 AVR_NUM_REG_BYTES = 32 + 1 /*SREG*/ + 2 /*SP*/ + 4 /*PC*/,
99 /* Pseudo registers. */
100 AVR_PSEUDO_PC_REGNUM = 35,
101 AVR_NUM_PSEUDO_REGS = 1,
103 AVR_PC_REG_INDEX = 35, /* index into array of registers */
105 AVR_MAX_PROLOGUE_SIZE = 64, /* bytes */
107 /* Count of pushed registers. From r2 to r17 (inclusively), r28, r29 */
110 /* Number of the last pushed register. r17 for current avr-gcc */
111 AVR_LAST_PUSHED_REGNUM = 17,
113 AVR_ARG1_REGNUM = 24, /* Single byte argument */
114 AVR_ARGN_REGNUM = 25, /* Multi byte argments */
115 AVR_LAST_ARG_REGNUM = 8, /* Last argument register */
117 AVR_RET1_REGNUM = 24, /* Single byte return value */
118 AVR_RETN_REGNUM = 25, /* Multi byte return value */
120 /* FIXME: TRoth/2002-01-??: Can we shift all these memory masks left 8
121 bits? Do these have to match the bfd vma values? It sure would make
122 things easier in the future if they didn't need to match.
124 Note: I chose these values so as to be consistent with bfd vma
127 TRoth/2002-04-08: There is already a conflict with very large programs
128 in the mega128. The mega128 has 128K instruction bytes (64K words),
129 thus the Most Significant Bit is 0x10000 which gets masked off my
132 The problem manifests itself when trying to set a breakpoint in a
133 function which resides in the upper half of the instruction space and
134 thus requires a 17-bit address.
136 For now, I've just removed the EEPROM mask and changed AVR_MEM_MASK
137 from 0x00ff0000 to 0x00f00000. Eeprom is not accessible from gdb yet,
138 but could be for some remote targets by just adding the correct offset
139 to the address and letting the remote target handle the low-level
140 details of actually accessing the eeprom. */
142 AVR_IMEM_START = 0x00000000, /* INSN memory */
143 AVR_SMEM_START = 0x00800000, /* SRAM memory */
145 /* No eeprom mask defined */
146 AVR_MEM_MASK = 0x00f00000, /* mask to determine memory space */
148 AVR_EMEM_START = 0x00810000, /* EEPROM memory */
149 AVR_MEM_MASK = 0x00ff0000, /* mask to determine memory space */
155 NORMAL and CALL are the typical types (the -mcall-prologues gcc option
156 causes the generation of the CALL type prologues). */
159 AVR_PROLOGUE_NONE, /* No prologue */
161 AVR_PROLOGUE_CALL, /* -mcall-prologues */
163 AVR_PROLOGUE_INTR, /* interrupt handler */
164 AVR_PROLOGUE_SIG, /* signal handler */
167 /* Any function with a frame looks like this
168 ....... <-SP POINTS HERE
169 LOCALS1 <-FP POINTS HERE
178 struct avr_unwind_cache
180 /* The previous frame's inner most stack address. Used as this
181 frame ID's stack_addr. */
183 /* The frame's base, optionally used by the high-level debug info. */
187 /* Table indicating the location of each and every register. */
188 struct trad_frame_saved_reg *saved_regs;
193 /* Number of bytes stored to the stack by call instructions.
194 2 bytes for avr1-5 and avrxmega1-5, 3 bytes for avr6 and avrxmega6-7. */
198 struct type *void_type;
199 /* Type for a function returning void. */
200 struct type *func_void_type;
201 /* Type for a pointer to a function. Used for the type of PC. */
202 struct type *pc_type;
205 /* Lookup the name of a register given it's number. */
208 avr_register_name (struct gdbarch *gdbarch, int regnum)
210 static const char * const register_names[] = {
211 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
212 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
213 "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
214 "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
220 if (regnum >= (sizeof (register_names) / sizeof (*register_names)))
222 return register_names[regnum];
225 /* Return the GDB type object for the "standard" data type
226 of data in register N. */
229 avr_register_type (struct gdbarch *gdbarch, int reg_nr)
231 if (reg_nr == AVR_PC_REGNUM)
232 return builtin_type (gdbarch)->builtin_uint32;
233 if (reg_nr == AVR_PSEUDO_PC_REGNUM)
234 return gdbarch_tdep (gdbarch)->pc_type;
235 if (reg_nr == AVR_SP_REGNUM)
236 return builtin_type (gdbarch)->builtin_data_ptr;
237 return builtin_type (gdbarch)->builtin_uint8;
240 /* Instruction address checks and convertions. */
243 avr_make_iaddr (CORE_ADDR x)
245 return ((x) | AVR_IMEM_START);
248 /* FIXME: TRoth: Really need to use a larger mask for instructions. Some
249 devices are already up to 128KBytes of flash space.
251 TRoth/2002-04-8: See comment above where AVR_IMEM_START is defined. */
254 avr_convert_iaddr_to_raw (CORE_ADDR x)
256 return ((x) & 0xffffffff);
259 /* SRAM address checks and convertions. */
262 avr_make_saddr (CORE_ADDR x)
264 /* Return 0 for NULL. */
268 return ((x) | AVR_SMEM_START);
272 avr_convert_saddr_to_raw (CORE_ADDR x)
274 return ((x) & 0xffffffff);
277 /* EEPROM address checks and convertions. I don't know if these will ever
278 actually be used, but I've added them just the same. TRoth */
280 /* TRoth/2002-04-08: Commented out for now to allow fix for problem with large
281 programs in the mega128. */
283 /* static CORE_ADDR */
284 /* avr_make_eaddr (CORE_ADDR x) */
286 /* return ((x) | AVR_EMEM_START); */
290 /* avr_eaddr_p (CORE_ADDR x) */
292 /* return (((x) & AVR_MEM_MASK) == AVR_EMEM_START); */
295 /* static CORE_ADDR */
296 /* avr_convert_eaddr_to_raw (CORE_ADDR x) */
298 /* return ((x) & 0xffffffff); */
301 /* Convert from address to pointer and vice-versa. */
304 avr_address_to_pointer (struct gdbarch *gdbarch,
305 struct type *type, gdb_byte *buf, CORE_ADDR addr)
307 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
309 /* Is it a data address in flash? */
310 if (AVR_TYPE_ADDRESS_CLASS_FLASH (type))
312 /* A data pointer in flash is byte addressed. */
313 store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
314 avr_convert_iaddr_to_raw (addr));
316 /* Is it a code address? */
317 else if (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC
318 || TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD)
320 /* A code pointer is word (16 bits) addressed. We shift the address down
321 by 1 bit to convert it to a pointer. */
322 store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
323 avr_convert_iaddr_to_raw (addr >> 1));
327 /* Strip off any upper segment bits. */
328 store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
329 avr_convert_saddr_to_raw (addr));
334 avr_pointer_to_address (struct gdbarch *gdbarch,
335 struct type *type, const gdb_byte *buf)
337 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
339 = extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order);
341 /* Is it a data address in flash? */
342 if (AVR_TYPE_ADDRESS_CLASS_FLASH (type))
344 /* A data pointer in flash is already byte addressed. */
345 return avr_make_iaddr (addr);
347 /* Is it a code address? */
348 else if (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC
349 || TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD
350 || TYPE_CODE_SPACE (TYPE_TARGET_TYPE (type)))
352 /* A code pointer is word (16 bits) addressed so we shift it up
353 by 1 bit to convert it to an address. */
354 return avr_make_iaddr (addr << 1);
357 return avr_make_saddr (addr);
361 avr_integer_to_address (struct gdbarch *gdbarch,
362 struct type *type, const gdb_byte *buf)
364 ULONGEST addr = unpack_long (type, buf);
366 return avr_make_saddr (addr);
370 avr_read_pc (readable_regcache *regcache)
374 regcache->cooked_read (AVR_PC_REGNUM, &pc);
375 return avr_make_iaddr (pc);
379 avr_write_pc (struct regcache *regcache, CORE_ADDR val)
381 regcache_cooked_write_unsigned (regcache, AVR_PC_REGNUM,
382 avr_convert_iaddr_to_raw (val));
385 static enum register_status
386 avr_pseudo_register_read (struct gdbarch *gdbarch, readable_regcache *regcache,
387 int regnum, gdb_byte *buf)
390 enum register_status status;
394 case AVR_PSEUDO_PC_REGNUM:
395 status = regcache->raw_read (AVR_PC_REGNUM, &val);
396 if (status != REG_VALID)
399 store_unsigned_integer (buf, 4, gdbarch_byte_order (gdbarch), val);
402 internal_error (__FILE__, __LINE__, _("invalid regnum"));
407 avr_pseudo_register_write (struct gdbarch *gdbarch, struct regcache *regcache,
408 int regnum, const gdb_byte *buf)
414 case AVR_PSEUDO_PC_REGNUM:
415 val = extract_unsigned_integer (buf, 4, gdbarch_byte_order (gdbarch));
417 regcache_raw_write_unsigned (regcache, AVR_PC_REGNUM, val);
420 internal_error (__FILE__, __LINE__, _("invalid regnum"));
424 /* Function: avr_scan_prologue
426 This function decodes an AVR function prologue to determine:
427 1) the size of the stack frame
428 2) which registers are saved on it
429 3) the offsets of saved regs
430 This information is stored in the avr_unwind_cache structure.
432 Some devices lack the sbiw instruction, so on those replace this:
438 A typical AVR function prologue with a frame pointer might look like this:
439 push rXX ; saved regs
445 sbiw r28,<LOCALS_SIZE>
446 in __tmp_reg__,__SREG__
449 out __SREG__,__tmp_reg__
452 A typical AVR function prologue without a frame pointer might look like
454 push rXX ; saved regs
457 A main function prologue looks like this:
458 ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)
459 ldi r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>)
463 A signal handler prologue looks like this:
466 in __tmp_reg__, __SREG__
469 push rXX ; save registers r18:r27, r30:r31
471 push r28 ; save frame pointer
475 sbiw r28, <LOCALS_SIZE>
479 A interrupt handler prologue looks like this:
483 in __tmp_reg__, __SREG__
486 push rXX ; save registers r18:r27, r30:r31
488 push r28 ; save frame pointer
492 sbiw r28, <LOCALS_SIZE>
498 A `-mcall-prologues' prologue looks like this (Note that the megas use a
499 jmp instead of a rjmp, thus the prologue is one word larger since jmp is a
500 32 bit insn and rjmp is a 16 bit insn):
501 ldi r26,lo8(<LOCALS_SIZE>)
502 ldi r27,hi8(<LOCALS_SIZE>)
503 ldi r30,pm_lo8(.L_foo_body)
504 ldi r31,pm_hi8(.L_foo_body)
505 rjmp __prologue_saves__+RRR
508 /* Not really part of a prologue, but still need to scan for it, is when a
509 function prologue moves values passed via registers as arguments to new
510 registers. In this case, all local variables live in registers, so there
511 may be some register saves. This is what it looks like:
515 There could be multiple movw's. If the target doesn't have a movw insn, it
516 will use two mov insns. This could be done after any of the above prologue
520 avr_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR pc_beg, CORE_ADDR pc_end,
521 struct avr_unwind_cache *info)
523 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
527 struct bound_minimal_symbol msymbol;
528 unsigned char prologue[AVR_MAX_PROLOGUE_SIZE];
532 len = pc_end - pc_beg;
533 if (len > AVR_MAX_PROLOGUE_SIZE)
534 len = AVR_MAX_PROLOGUE_SIZE;
536 /* FIXME: TRoth/2003-06-11: This could be made more efficient by only
537 reading in the bytes of the prologue. The problem is that the figuring
538 out where the end of the prologue is is a bit difficult. The old code
539 tried to do that, but failed quite often. */
540 read_memory (pc_beg, prologue, len);
542 /* Scanning main()'s prologue
543 ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)
544 ldi r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>)
551 static const unsigned char img[] = {
552 0xde, 0xbf, /* out __SP_H__,r29 */
553 0xcd, 0xbf /* out __SP_L__,r28 */
556 insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
557 /* ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>) */
558 if ((insn & 0xf0f0) == 0xe0c0)
560 locals = (insn & 0xf) | ((insn & 0x0f00) >> 4);
561 insn = extract_unsigned_integer (&prologue[vpc + 2], 2, byte_order);
562 /* ldi r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>) */
563 if ((insn & 0xf0f0) == 0xe0d0)
565 locals |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
566 if (vpc + 4 + sizeof (img) < len
567 && memcmp (prologue + vpc + 4, img, sizeof (img)) == 0)
569 info->prologue_type = AVR_PROLOGUE_MAIN;
577 /* Scanning `-mcall-prologues' prologue
578 Classic prologue is 10 bytes, mega prologue is a 12 bytes long */
580 while (1) /* Using a while to avoid many goto's */
587 /* At least the fifth instruction must have been executed to
588 modify frame shape. */
592 insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
593 /* ldi r26,<LOCALS_SIZE> */
594 if ((insn & 0xf0f0) != 0xe0a0)
596 loc_size = (insn & 0xf) | ((insn & 0x0f00) >> 4);
599 insn = extract_unsigned_integer (&prologue[vpc + 2], 2, byte_order);
600 /* ldi r27,<LOCALS_SIZE> / 256 */
601 if ((insn & 0xf0f0) != 0xe0b0)
603 loc_size |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
606 insn = extract_unsigned_integer (&prologue[vpc + 4], 2, byte_order);
607 /* ldi r30,pm_lo8(.L_foo_body) */
608 if ((insn & 0xf0f0) != 0xe0e0)
610 body_addr = (insn & 0xf) | ((insn & 0x0f00) >> 4);
613 insn = extract_unsigned_integer (&prologue[vpc + 6], 2, byte_order);
614 /* ldi r31,pm_hi8(.L_foo_body) */
615 if ((insn & 0xf0f0) != 0xe0f0)
617 body_addr |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
620 msymbol = lookup_minimal_symbol ("__prologue_saves__", NULL, NULL);
624 insn = extract_unsigned_integer (&prologue[vpc + 8], 2, byte_order);
625 /* rjmp __prologue_saves__+RRR */
626 if ((insn & 0xf000) == 0xc000)
628 /* Extract PC relative offset from RJMP */
629 i = (insn & 0xfff) | (insn & 0x800 ? (-1 ^ 0xfff) : 0);
630 /* Convert offset to byte addressable mode */
632 /* Destination address */
635 if (body_addr != (pc_beg + 10)/2)
640 else if ((insn & 0xfe0e) == 0x940c)
642 /* Extract absolute PC address from JMP */
643 i = (((insn & 0x1) | ((insn & 0x1f0) >> 3) << 16)
644 | (extract_unsigned_integer (&prologue[vpc + 10], 2, byte_order)
646 /* Convert address to byte addressable mode */
649 if (body_addr != (pc_beg + 12)/2)
657 /* Resolve offset (in words) from __prologue_saves__ symbol.
658 Which is a pushes count in `-mcall-prologues' mode */
659 num_pushes = AVR_MAX_PUSHES - (i - BMSYMBOL_VALUE_ADDRESS (msymbol)) / 2;
661 if (num_pushes > AVR_MAX_PUSHES)
663 fprintf_unfiltered (gdb_stderr, _("Num pushes too large: %d\n"),
672 info->saved_regs[AVR_FP_REGNUM + 1].addr = num_pushes;
674 info->saved_regs[AVR_FP_REGNUM].addr = num_pushes - 1;
677 for (from = AVR_LAST_PUSHED_REGNUM + 1 - (num_pushes - 2);
678 from <= AVR_LAST_PUSHED_REGNUM; ++from)
679 info->saved_regs [from].addr = ++i;
681 info->size = loc_size + num_pushes;
682 info->prologue_type = AVR_PROLOGUE_CALL;
684 return pc_beg + pc_offset;
687 /* Scan for the beginning of the prologue for an interrupt or signal
688 function. Note that we have to set the prologue type here since the
689 third stage of the prologue may not be present (e.g. no saved registered
690 or changing of the SP register). */
694 static const unsigned char img[] = {
695 0x78, 0x94, /* sei */
696 0x1f, 0x92, /* push r1 */
697 0x0f, 0x92, /* push r0 */
698 0x0f, 0xb6, /* in r0,0x3f SREG */
699 0x0f, 0x92, /* push r0 */
700 0x11, 0x24 /* clr r1 */
702 if (len >= sizeof (img)
703 && memcmp (prologue, img, sizeof (img)) == 0)
705 info->prologue_type = AVR_PROLOGUE_INTR;
707 info->saved_regs[AVR_SREG_REGNUM].addr = 3;
708 info->saved_regs[0].addr = 2;
709 info->saved_regs[1].addr = 1;
712 else if (len >= sizeof (img) - 2
713 && memcmp (img + 2, prologue, sizeof (img) - 2) == 0)
715 info->prologue_type = AVR_PROLOGUE_SIG;
716 vpc += sizeof (img) - 2;
717 info->saved_regs[AVR_SREG_REGNUM].addr = 3;
718 info->saved_regs[0].addr = 2;
719 info->saved_regs[1].addr = 1;
724 /* First stage of the prologue scanning.
725 Scan pushes (saved registers) */
727 for (; vpc < len; vpc += 2)
729 insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
730 if ((insn & 0xfe0f) == 0x920f) /* push rXX */
732 /* Bits 4-9 contain a mask for registers R0-R32. */
733 int regno = (insn & 0x1f0) >> 4;
735 info->saved_regs[regno].addr = info->size;
742 gdb_assert (vpc < AVR_MAX_PROLOGUE_SIZE);
744 /* Handle static small stack allocation using rcall or push. */
746 while (scan_stage == 1 && vpc < len)
748 insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
749 if (insn == 0xd000) /* rcall .+0 */
751 info->size += gdbarch_tdep (gdbarch)->call_length;
754 else if (insn == 0x920f || insn == 0x921f) /* push r0 or push r1 */
763 /* Second stage of the prologue scanning.
768 if (scan_stage == 1 && vpc < len)
770 static const unsigned char img[] = {
771 0xcd, 0xb7, /* in r28,__SP_L__ */
772 0xde, 0xb7 /* in r29,__SP_H__ */
775 if (vpc + sizeof (img) < len
776 && memcmp (prologue + vpc, img, sizeof (img)) == 0)
783 /* Third stage of the prologue scanning. (Really two stages).
785 sbiw r28,XX or subi r28,lo8(XX)
787 in __tmp_reg__,__SREG__
790 out __SREG__,__tmp_reg__
793 if (scan_stage == 2 && vpc < len)
796 static const unsigned char img[] = {
797 0x0f, 0xb6, /* in r0,0x3f */
798 0xf8, 0x94, /* cli */
799 0xde, 0xbf, /* out 0x3e,r29 ; SPH */
800 0x0f, 0xbe, /* out 0x3f,r0 ; SREG */
801 0xcd, 0xbf /* out 0x3d,r28 ; SPL */
803 static const unsigned char img_sig[] = {
804 0xde, 0xbf, /* out 0x3e,r29 ; SPH */
805 0xcd, 0xbf /* out 0x3d,r28 ; SPL */
807 static const unsigned char img_int[] = {
808 0xf8, 0x94, /* cli */
809 0xde, 0xbf, /* out 0x3e,r29 ; SPH */
810 0x78, 0x94, /* sei */
811 0xcd, 0xbf /* out 0x3d,r28 ; SPL */
814 insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
815 if ((insn & 0xff30) == 0x9720) /* sbiw r28,XXX */
817 locals_size = (insn & 0xf) | ((insn & 0xc0) >> 2);
820 else if ((insn & 0xf0f0) == 0x50c0) /* subi r28,lo8(XX) */
822 locals_size = (insn & 0xf) | ((insn & 0xf00) >> 4);
824 insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
826 locals_size += ((insn & 0xf) | ((insn & 0xf00) >> 4)) << 8;
831 /* Scan the last part of the prologue. May not be present for interrupt
832 or signal handler functions, which is why we set the prologue type
833 when we saw the beginning of the prologue previously. */
835 if (vpc + sizeof (img_sig) < len
836 && memcmp (prologue + vpc, img_sig, sizeof (img_sig)) == 0)
838 vpc += sizeof (img_sig);
840 else if (vpc + sizeof (img_int) < len
841 && memcmp (prologue + vpc, img_int, sizeof (img_int)) == 0)
843 vpc += sizeof (img_int);
845 if (vpc + sizeof (img) < len
846 && memcmp (prologue + vpc, img, sizeof (img)) == 0)
848 info->prologue_type = AVR_PROLOGUE_NORMAL;
852 info->size += locals_size;
857 /* If we got this far, we could not scan the prologue, so just return the pc
858 of the frame plus an adjustment for argument move insns. */
860 for (; vpc < len; vpc += 2)
862 insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
863 if ((insn & 0xff00) == 0x0100) /* movw rXX, rYY */
865 else if ((insn & 0xfc00) == 0x2c00) /* mov rXX, rYY */
875 avr_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
877 CORE_ADDR func_addr, func_end;
878 CORE_ADDR post_prologue_pc;
880 /* See what the symbol table says */
882 if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
885 post_prologue_pc = skip_prologue_using_sal (gdbarch, func_addr);
886 if (post_prologue_pc != 0)
887 return std::max (pc, post_prologue_pc);
890 CORE_ADDR prologue_end = pc;
891 struct avr_unwind_cache info = {0};
892 struct trad_frame_saved_reg saved_regs[AVR_NUM_REGS];
894 info.saved_regs = saved_regs;
896 /* Need to run the prologue scanner to figure out if the function has a
897 prologue and possibly skip over moving arguments passed via registers
898 to other registers. */
900 prologue_end = avr_scan_prologue (gdbarch, func_addr, func_end, &info);
902 if (info.prologue_type != AVR_PROLOGUE_NONE)
906 /* Either we didn't find the start of this function (nothing we can do),
907 or there's no line info, or the line after the prologue is after
908 the end of the function (there probably isn't a prologue). */
913 /* Not all avr devices support the BREAK insn. Those that don't should treat
914 it as a NOP. Thus, it should be ok. Since the avr is currently a remote
915 only target, this shouldn't be a problem (I hope). TRoth/2003-05-14 */
917 constexpr gdb_byte avr_break_insn [] = { 0x98, 0x95 };
919 typedef BP_MANIPULATION (avr_break_insn) avr_breakpoint;
921 /* Determine, for architecture GDBARCH, how a return value of TYPE
922 should be returned. If it is supposed to be returned in registers,
923 and READBUF is non-zero, read the appropriate value from REGCACHE,
924 and copy it into READBUF. If WRITEBUF is non-zero, write the value
925 from WRITEBUF into REGCACHE. */
927 static enum return_value_convention
928 avr_return_value (struct gdbarch *gdbarch, struct value *function,
929 struct type *valtype, struct regcache *regcache,
930 gdb_byte *readbuf, const gdb_byte *writebuf)
933 /* Single byte are returned in r24.
934 Otherwise, the MSB of the return value is always in r25, calculate which
935 register holds the LSB. */
938 if ((TYPE_CODE (valtype) == TYPE_CODE_STRUCT
939 || TYPE_CODE (valtype) == TYPE_CODE_UNION
940 || TYPE_CODE (valtype) == TYPE_CODE_ARRAY)
941 && TYPE_LENGTH (valtype) > 8)
942 return RETURN_VALUE_STRUCT_CONVENTION;
944 if (TYPE_LENGTH (valtype) <= 2)
946 else if (TYPE_LENGTH (valtype) <= 4)
948 else if (TYPE_LENGTH (valtype) <= 8)
951 gdb_assert_not_reached ("unexpected type length");
953 if (writebuf != NULL)
955 for (i = 0; i < TYPE_LENGTH (valtype); i++)
956 regcache_cooked_write (regcache, lsb_reg + i, writebuf + i);
961 for (i = 0; i < TYPE_LENGTH (valtype); i++)
962 regcache->cooked_read (lsb_reg + i, readbuf + i);
965 return RETURN_VALUE_REGISTER_CONVENTION;
969 /* Put here the code to store, into fi->saved_regs, the addresses of
970 the saved registers of frame described by FRAME_INFO. This
971 includes special registers such as pc and fp saved in special ways
972 in the stack frame. sp is even more special: the address we return
973 for it IS the sp for the next frame. */
975 static struct avr_unwind_cache *
976 avr_frame_unwind_cache (struct frame_info *this_frame,
977 void **this_prologue_cache)
979 CORE_ADDR start_pc, current_pc;
982 struct avr_unwind_cache *info;
983 struct gdbarch *gdbarch;
984 struct gdbarch_tdep *tdep;
987 if (*this_prologue_cache)
988 return (struct avr_unwind_cache *) *this_prologue_cache;
990 info = FRAME_OBSTACK_ZALLOC (struct avr_unwind_cache);
991 *this_prologue_cache = info;
992 info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
995 info->prologue_type = AVR_PROLOGUE_NONE;
997 start_pc = get_frame_func (this_frame);
998 current_pc = get_frame_pc (this_frame);
999 if ((start_pc > 0) && (start_pc <= current_pc))
1000 avr_scan_prologue (get_frame_arch (this_frame),
1001 start_pc, current_pc, info);
1003 if ((info->prologue_type != AVR_PROLOGUE_NONE)
1004 && (info->prologue_type != AVR_PROLOGUE_MAIN))
1006 ULONGEST high_base; /* High byte of FP */
1008 /* The SP was moved to the FP. This indicates that a new frame
1009 was created. Get THIS frame's FP value by unwinding it from
1011 this_base = get_frame_register_unsigned (this_frame, AVR_FP_REGNUM);
1012 high_base = get_frame_register_unsigned (this_frame, AVR_FP_REGNUM + 1);
1013 this_base += (high_base << 8);
1015 /* The FP points at the last saved register. Adjust the FP back
1016 to before the first saved register giving the SP. */
1017 prev_sp = this_base + info->size;
1021 /* Assume that the FP is this frame's SP but with that pushed
1022 stack space added back. */
1023 this_base = get_frame_register_unsigned (this_frame, AVR_SP_REGNUM);
1024 prev_sp = this_base + info->size;
1027 /* Add 1 here to adjust for the post-decrement nature of the push
1029 info->prev_sp = avr_make_saddr (prev_sp + 1);
1030 info->base = avr_make_saddr (this_base);
1032 gdbarch = get_frame_arch (this_frame);
1034 /* Adjust all the saved registers so that they contain addresses and not
1036 for (i = 0; i < gdbarch_num_regs (gdbarch) - 1; i++)
1037 if (info->saved_regs[i].addr > 0)
1038 info->saved_regs[i].addr = info->prev_sp - info->saved_regs[i].addr;
1040 /* Except for the main and startup code, the return PC is always saved on
1041 the stack and is at the base of the frame. */
1043 if (info->prologue_type != AVR_PROLOGUE_MAIN)
1044 info->saved_regs[AVR_PC_REGNUM].addr = info->prev_sp;
1046 /* The previous frame's SP needed to be computed. Save the computed
1048 tdep = gdbarch_tdep (gdbarch);
1049 trad_frame_set_value (info->saved_regs, AVR_SP_REGNUM,
1050 info->prev_sp - 1 + tdep->call_length);
1056 avr_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
1060 pc = frame_unwind_register_unsigned (next_frame, AVR_PC_REGNUM);
1062 return avr_make_iaddr (pc);
1066 avr_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
1070 sp = frame_unwind_register_unsigned (next_frame, AVR_SP_REGNUM);
1072 return avr_make_saddr (sp);
1075 /* Given a GDB frame, determine the address of the calling function's
1076 frame. This will be used to create a new GDB frame struct. */
1079 avr_frame_this_id (struct frame_info *this_frame,
1080 void **this_prologue_cache,
1081 struct frame_id *this_id)
1083 struct avr_unwind_cache *info
1084 = avr_frame_unwind_cache (this_frame, this_prologue_cache);
1089 /* The FUNC is easy. */
1090 func = get_frame_func (this_frame);
1092 /* Hopefully the prologue analysis either correctly determined the
1093 frame's base (which is the SP from the previous frame), or set
1094 that base to "NULL". */
1095 base = info->prev_sp;
1099 id = frame_id_build (base, func);
1103 static struct value *
1104 avr_frame_prev_register (struct frame_info *this_frame,
1105 void **this_prologue_cache, int regnum)
1107 struct avr_unwind_cache *info
1108 = avr_frame_unwind_cache (this_frame, this_prologue_cache);
1110 if (regnum == AVR_PC_REGNUM || regnum == AVR_PSEUDO_PC_REGNUM)
1112 if (trad_frame_addr_p (info->saved_regs, AVR_PC_REGNUM))
1114 /* Reading the return PC from the PC register is slightly
1115 abnormal. register_size(AVR_PC_REGNUM) says it is 4 bytes,
1116 but in reality, only two bytes (3 in upcoming mega256) are
1117 stored on the stack.
1119 Also, note that the value on the stack is an addr to a word
1120 not a byte, so we will need to multiply it by two at some
1123 And to confuse matters even more, the return address stored
1124 on the stack is in big endian byte order, even though most
1125 everything else about the avr is little endian. Ick! */
1129 struct gdbarch *gdbarch = get_frame_arch (this_frame);
1130 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
1132 read_memory (info->saved_regs[AVR_PC_REGNUM].addr,
1133 buf, tdep->call_length);
1135 /* Extract the PC read from memory as a big-endian. */
1137 for (i = 0; i < tdep->call_length; i++)
1138 pc = (pc << 8) | buf[i];
1140 if (regnum == AVR_PC_REGNUM)
1143 return frame_unwind_got_constant (this_frame, regnum, pc);
1146 return frame_unwind_got_optimized (this_frame, regnum);
1149 return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
1152 static const struct frame_unwind avr_frame_unwind = {
1154 default_frame_unwind_stop_reason,
1156 avr_frame_prev_register,
1158 default_frame_sniffer
1162 avr_frame_base_address (struct frame_info *this_frame, void **this_cache)
1164 struct avr_unwind_cache *info
1165 = avr_frame_unwind_cache (this_frame, this_cache);
1170 static const struct frame_base avr_frame_base = {
1172 avr_frame_base_address,
1173 avr_frame_base_address,
1174 avr_frame_base_address
1177 /* Assuming THIS_FRAME is a dummy, return the frame ID of that dummy
1178 frame. The frame ID's base needs to match the TOS value saved by
1179 save_dummy_frame_tos(), and the PC match the dummy frame's breakpoint. */
1181 static struct frame_id
1182 avr_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
1186 base = get_frame_register_unsigned (this_frame, AVR_SP_REGNUM);
1187 return frame_id_build (avr_make_saddr (base), get_frame_pc (this_frame));
1190 /* When arguments must be pushed onto the stack, they go on in reverse
1191 order. The below implements a FILO (stack) to do this. */
1196 struct stack_item *prev;
1200 static struct stack_item *
1201 push_stack_item (struct stack_item *prev, const bfd_byte *contents, int len)
1203 struct stack_item *si;
1204 si = XNEW (struct stack_item);
1205 si->data = (gdb_byte *) xmalloc (len);
1208 memcpy (si->data, contents, len);
1212 static struct stack_item *pop_stack_item (struct stack_item *si);
1213 static struct stack_item *
1214 pop_stack_item (struct stack_item *si)
1216 struct stack_item *dead = si;
1223 /* Setup the function arguments for calling a function in the inferior.
1225 On the AVR architecture, there are 18 registers (R25 to R8) which are
1226 dedicated for passing function arguments. Up to the first 18 arguments
1227 (depending on size) may go into these registers. The rest go on the stack.
1229 All arguments are aligned to start in even-numbered registers (odd-sized
1230 arguments, including char, have one free register above them). For example,
1231 an int in arg1 and a char in arg2 would be passed as such:
1236 Arguments that are larger than 2 bytes will be split between two or more
1237 registers as available, but will NOT be split between a register and the
1238 stack. Arguments that go onto the stack are pushed last arg first (this is
1239 similar to the d10v). */
1241 /* NOTE: TRoth/2003-06-17: The rest of this comment is old looks to be
1244 An exceptional case exists for struct arguments (and possibly other
1245 aggregates such as arrays) -- if the size is larger than WORDSIZE bytes but
1246 not a multiple of WORDSIZE bytes. In this case the argument is never split
1247 between the registers and the stack, but instead is copied in its entirety
1248 onto the stack, AND also copied into as many registers as there is room
1249 for. In other words, space in registers permitting, two copies of the same
1250 argument are passed in. As far as I can tell, only the one on the stack is
1251 used, although that may be a function of the level of compiler
1252 optimization. I suspect this is a compiler bug. Arguments of these odd
1253 sizes are left-justified within the word (as opposed to arguments smaller
1254 than WORDSIZE bytes, which are right-justified).
1256 If the function is to return an aggregate type such as a struct, the caller
1257 must allocate space into which the callee will copy the return value. In
1258 this case, a pointer to the return value location is passed into the callee
1259 in register R0, which displaces one of the other arguments passed in via
1260 registers R0 to R2. */
1263 avr_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
1264 struct regcache *regcache, CORE_ADDR bp_addr,
1265 int nargs, struct value **args, CORE_ADDR sp,
1266 int struct_return, CORE_ADDR struct_addr)
1270 int call_length = gdbarch_tdep (gdbarch)->call_length;
1271 CORE_ADDR return_pc = avr_convert_iaddr_to_raw (bp_addr);
1272 int regnum = AVR_ARGN_REGNUM;
1273 struct stack_item *si = NULL;
1277 regcache_cooked_write_unsigned
1278 (regcache, regnum--, (struct_addr >> 8) & 0xff);
1279 regcache_cooked_write_unsigned
1280 (regcache, regnum--, struct_addr & 0xff);
1281 /* SP being post decremented, we need to reserve one byte so that the
1282 return address won't overwrite the result (or vice-versa). */
1283 if (sp == struct_addr)
1287 for (i = 0; i < nargs; i++)
1291 struct value *arg = args[i];
1292 struct type *type = check_typedef (value_type (arg));
1293 const bfd_byte *contents = value_contents (arg);
1294 int len = TYPE_LENGTH (type);
1296 /* Calculate the potential last register needed.
1297 E.g. For length 2, registers regnum and regnum-1 (say 25 and 24)
1298 shall be used. So, last needed register will be regnum-1(24). */
1299 last_regnum = regnum - (len + (len & 1)) + 1;
1301 /* If there are registers available, use them. Once we start putting
1302 stuff on the stack, all subsequent args go on stack. */
1303 if ((si == NULL) && (last_regnum >= AVR_LAST_ARG_REGNUM))
1305 /* Skip a register for odd length args. */
1309 /* Write MSB of argument into register and subsequent bytes in
1310 decreasing register numbers. */
1311 for (j = 0; j < len; j++)
1312 regcache_cooked_write_unsigned
1313 (regcache, regnum--, contents[len - j - 1]);
1315 /* No registers available, push the args onto the stack. */
1318 /* From here on, we don't care about regnum. */
1319 si = push_stack_item (si, contents, len);
1323 /* Push args onto the stack. */
1327 /* Add 1 to sp here to account for post decr nature of pushes. */
1328 write_memory (sp + 1, si->data, si->len);
1329 si = pop_stack_item (si);
1332 /* Set the return address. For the avr, the return address is the BP_ADDR.
1333 Need to push the return address onto the stack noting that it needs to be
1334 in big-endian order on the stack. */
1335 for (i = 1; i <= call_length; i++)
1337 buf[call_length - i] = return_pc & 0xff;
1342 /* Use 'sp + 1' since pushes are post decr ops. */
1343 write_memory (sp + 1, buf, call_length);
1345 /* Finally, update the SP register. */
1346 regcache_cooked_write_unsigned (regcache, AVR_SP_REGNUM,
1347 avr_convert_saddr_to_raw (sp));
1349 /* Return SP value for the dummy frame, where the return address hasn't been
1351 return sp + call_length;
1354 /* Unfortunately dwarf2 register for SP is 32. */
1357 avr_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
1359 if (reg >= 0 && reg < 32)
1362 return AVR_SP_REGNUM;
1366 /* Implementation of `address_class_type_flags' gdbarch method.
1368 This method maps DW_AT_address_class attributes to a
1369 type_instance_flag_value. */
1372 avr_address_class_type_flags (int byte_size, int dwarf2_addr_class)
1374 /* The value 1 of the DW_AT_address_class attribute corresponds to the
1375 __flash qualifier. Note that this attribute is only valid with
1376 pointer types and therefore the flag is set to the pointer type and
1377 not its target type. */
1378 if (dwarf2_addr_class == 1 && byte_size == 2)
1379 return AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH;
1383 /* Implementation of `address_class_type_flags_to_name' gdbarch method.
1385 Convert a type_instance_flag_value to an address space qualifier. */
1388 avr_address_class_type_flags_to_name (struct gdbarch *gdbarch, int type_flags)
1390 if (type_flags & AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH)
1396 /* Implementation of `address_class_name_to_type_flags' gdbarch method.
1398 Convert an address space qualifier to a type_instance_flag_value. */
1401 avr_address_class_name_to_type_flags (struct gdbarch *gdbarch,
1403 int *type_flags_ptr)
1405 if (strcmp (name, "flash") == 0)
1407 *type_flags_ptr = AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH;
1414 /* Initialize the gdbarch structure for the AVR's. */
1416 static struct gdbarch *
1417 avr_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
1419 struct gdbarch *gdbarch;
1420 struct gdbarch_tdep *tdep;
1421 struct gdbarch_list *best_arch;
1424 /* Avr-6 call instructions save 3 bytes. */
1425 switch (info.bfd_arch_info->mach)
1428 case bfd_mach_avrxmega1:
1430 case bfd_mach_avrxmega2:
1432 case bfd_mach_avrxmega3:
1434 case bfd_mach_avrxmega4:
1436 case bfd_mach_avrxmega5:
1441 case bfd_mach_avrxmega6:
1442 case bfd_mach_avrxmega7:
1447 /* If there is already a candidate, use it. */
1448 for (best_arch = gdbarch_list_lookup_by_info (arches, &info);
1450 best_arch = gdbarch_list_lookup_by_info (best_arch->next, &info))
1452 if (gdbarch_tdep (best_arch->gdbarch)->call_length == call_length)
1453 return best_arch->gdbarch;
1456 /* None found, create a new architecture from the information provided. */
1457 tdep = XCNEW (struct gdbarch_tdep);
1458 gdbarch = gdbarch_alloc (&info, tdep);
1460 tdep->call_length = call_length;
1462 /* Create a type for PC. We can't use builtin types here, as they may not
1464 tdep->void_type = arch_type (gdbarch, TYPE_CODE_VOID, TARGET_CHAR_BIT,
1466 tdep->func_void_type = make_function_type (tdep->void_type, NULL);
1467 tdep->pc_type = arch_pointer_type (gdbarch, 4 * TARGET_CHAR_BIT, NULL,
1468 tdep->func_void_type);
1470 set_gdbarch_short_bit (gdbarch, 2 * TARGET_CHAR_BIT);
1471 set_gdbarch_int_bit (gdbarch, 2 * TARGET_CHAR_BIT);
1472 set_gdbarch_long_bit (gdbarch, 4 * TARGET_CHAR_BIT);
1473 set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT);
1474 set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
1475 set_gdbarch_addr_bit (gdbarch, 32);
1477 set_gdbarch_wchar_bit (gdbarch, 2 * TARGET_CHAR_BIT);
1478 set_gdbarch_wchar_signed (gdbarch, 1);
1480 set_gdbarch_float_bit (gdbarch, 4 * TARGET_CHAR_BIT);
1481 set_gdbarch_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);
1482 set_gdbarch_long_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);
1484 set_gdbarch_float_format (gdbarch, floatformats_ieee_single);
1485 set_gdbarch_double_format (gdbarch, floatformats_ieee_single);
1486 set_gdbarch_long_double_format (gdbarch, floatformats_ieee_single);
1488 set_gdbarch_read_pc (gdbarch, avr_read_pc);
1489 set_gdbarch_write_pc (gdbarch, avr_write_pc);
1491 set_gdbarch_num_regs (gdbarch, AVR_NUM_REGS);
1493 set_gdbarch_sp_regnum (gdbarch, AVR_SP_REGNUM);
1494 set_gdbarch_pc_regnum (gdbarch, AVR_PC_REGNUM);
1496 set_gdbarch_register_name (gdbarch, avr_register_name);
1497 set_gdbarch_register_type (gdbarch, avr_register_type);
1499 set_gdbarch_num_pseudo_regs (gdbarch, AVR_NUM_PSEUDO_REGS);
1500 set_gdbarch_pseudo_register_read (gdbarch, avr_pseudo_register_read);
1501 set_gdbarch_pseudo_register_write (gdbarch, avr_pseudo_register_write);
1503 set_gdbarch_return_value (gdbarch, avr_return_value);
1505 set_gdbarch_push_dummy_call (gdbarch, avr_push_dummy_call);
1507 set_gdbarch_dwarf2_reg_to_regnum (gdbarch, avr_dwarf_reg_to_regnum);
1509 set_gdbarch_address_to_pointer (gdbarch, avr_address_to_pointer);
1510 set_gdbarch_pointer_to_address (gdbarch, avr_pointer_to_address);
1511 set_gdbarch_integer_to_address (gdbarch, avr_integer_to_address);
1513 set_gdbarch_skip_prologue (gdbarch, avr_skip_prologue);
1514 set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
1516 set_gdbarch_breakpoint_kind_from_pc (gdbarch, avr_breakpoint::kind_from_pc);
1517 set_gdbarch_sw_breakpoint_from_kind (gdbarch, avr_breakpoint::bp_from_kind);
1519 frame_unwind_append_unwinder (gdbarch, &avr_frame_unwind);
1520 frame_base_set_default (gdbarch, &avr_frame_base);
1522 set_gdbarch_dummy_id (gdbarch, avr_dummy_id);
1524 set_gdbarch_unwind_pc (gdbarch, avr_unwind_pc);
1525 set_gdbarch_unwind_sp (gdbarch, avr_unwind_sp);
1527 set_gdbarch_address_class_type_flags (gdbarch, avr_address_class_type_flags);
1528 set_gdbarch_address_class_name_to_type_flags
1529 (gdbarch, avr_address_class_name_to_type_flags);
1530 set_gdbarch_address_class_type_flags_to_name
1531 (gdbarch, avr_address_class_type_flags_to_name);
1536 /* Send a query request to the avr remote target asking for values of the io
1537 registers. If args parameter is not NULL, then the user has requested info
1538 on a specific io register [This still needs implemented and is ignored for
1539 now]. The query string should be one of these forms:
1541 "Ravr.io_reg" -> reply is "NN" number of io registers
1543 "Ravr.io_reg:addr,len" where addr is first register and len is number of
1544 registers to be read. The reply should be "<NAME>,VV;" for each io register
1545 where, <NAME> is a string, and VV is the hex value of the register.
1547 All io registers are 8-bit. */
1550 avr_io_reg_read_command (const char *args, int from_tty)
1553 unsigned int nreg = 0;
1556 /* Find out how many io registers the target has. */
1557 gdb::optional<gdb::byte_vector> buf
1558 = target_read_alloc (target_stack, TARGET_OBJECT_AVR, "avr.io_reg");
1562 fprintf_unfiltered (gdb_stderr,
1563 _("ERR: info io_registers NOT supported "
1564 "by current target\n"));
1568 const char *bufstr = (const char *) buf->data ();
1570 if (sscanf (bufstr, "%x", &nreg) != 1)
1572 fprintf_unfiltered (gdb_stderr,
1573 _("Error fetching number of io registers\n"));
1577 reinitialize_more_filter ();
1579 printf_unfiltered (_("Target has %u io registers:\n\n"), nreg);
1581 /* only fetch up to 8 registers at a time to keep the buffer small */
1584 for (int i = 0; i < nreg; i += step)
1586 /* how many registers this round? */
1589 j = nreg - i; /* last block is less than 8 registers */
1591 snprintf (query, sizeof (query) - 1, "avr.io_reg:%x,%x", i, j);
1592 buf = target_read_alloc (target_stack, TARGET_OBJECT_AVR, query);
1596 fprintf_unfiltered (gdb_stderr,
1597 _("ERR: error reading avr.io_reg:%x,%x\n"),
1602 const char *p = (const char *) buf->data ();
1603 for (int k = i; k < (i + j); k++)
1605 if (sscanf (p, "%[^,],%x;", query, &val) == 2)
1607 printf_filtered ("[%02x] %-15s : %02x\n", k, query, val);
1608 while ((*p != ';') && (*p != '\0'))
1610 p++; /* skip over ';' */
1619 _initialize_avr_tdep (void)
1621 register_gdbarch_init (bfd_arch_avr, avr_gdbarch_init);
1623 /* Add a new command to allow the user to query the avr remote target for
1624 the values of the io space registers in a saner way than just using
1627 /* FIXME: TRoth/2002-02-18: This should probably be changed to 'info avr
1628 io_registers' to signify it is not available on other platforms. */
1630 add_info ("io_registers", avr_io_reg_read_command,
1631 _("query remote avr target for io space register values"));