1 /* Remote debugging interface for MIPS remote debugging protocol.
2 Copyright 1993 Free Software Foundation, Inc.
3 Contributed by Cygnus Support. Written by Ian Lance Taylor
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
34 /* Prototypes for local functions. */
37 mips_readchar
PARAMS ((int timeout
));
40 mips_receive_header
PARAMS ((unsigned char *hdr
, int *pgarbage
, int ch
,
44 mips_receive_trailer
PARAMS ((unsigned char *trlr
, int *pgarbage
, int *pch
,
47 static int mips_cksum
PARAMS ((const unsigned char *hdr
,
48 const unsigned char *data
,
52 mips_send_packet
PARAMS ((const char *s
, int get_ack
));
55 mips_receive_packet
PARAMS ((char *buff
));
58 mips_request
PARAMS ((char cmd
, unsigned int addr
, unsigned int data
,
62 mips_initialize
PARAMS ((void));
65 mips_open
PARAMS ((char *name
, int from_tty
));
68 mips_close
PARAMS ((int quitting
));
71 mips_detach
PARAMS ((char *args
, int from_tty
));
74 mips_resume
PARAMS ((int step
, int siggnal
));
77 mips_wait
PARAMS ((WAITTYPE
*status
));
80 mips_map_regno
PARAMS ((int regno
));
83 mips_fetch_registers
PARAMS ((int regno
));
86 mips_prepare_to_store
PARAMS ((void));
89 mips_store_registers
PARAMS ((int regno
));
92 mips_fetch_word
PARAMS ((CORE_ADDR addr
));
95 mips_store_word
PARAMS ((CORE_ADDR addr
, int value
));
98 mips_xfer_memory
PARAMS ((CORE_ADDR memaddr
, char *myaddr
, int len
,
99 int write
, struct target_ops
*ignore
));
102 mips_files_info
PARAMS ((struct target_ops
*ignore
));
105 mips_load
PARAMS ((char *args
, int from_tty
));
108 mips_create_inferior
PARAMS ((char *execfile
, char *args
, char **env
));
111 mips_mourn_inferior
PARAMS ((void));
113 /* A forward declaration. */
114 extern struct target_ops mips_ops
;
116 /* The MIPS remote debugging interface is built on top of a simple
117 packet protocol. Each packet is organized as follows:
119 SYN The first character is always a SYN (ASCII 026, or ^V). SYN
120 may not appear anywhere else in the packet. Any time a SYN is
121 seen, a new packet should be assumed to have begun.
124 This byte contains the upper five bits of the logical length
125 of the data section, plus a single bit indicating whether this
126 is a data packet or an acknowledgement. The documentation
127 indicates that this bit is 1 for a data packet, but the actual
128 board uses 1 for an acknowledgement. The value of the byte is
129 0x40 + (ack ? 0x20 : 0) + (len >> 6)
130 (we always have 0 <= len < 1024). Acknowledgement packets do
131 not carry data, and must have a data length of 0.
133 LEN1 This byte contains the lower six bits of the logical length of
134 the data section. The value is
137 SEQ This byte contains the six bit sequence number of the packet.
140 An acknowlegment packet contains the sequence number of the
141 packet being acknowledged plus 1 module 64. Data packets are
142 transmitted in sequence. There may only be one outstanding
143 unacknowledged data packet at a time. The sequence numbers
144 are independent in each direction. If an acknowledgement for
145 the previous packet is received (i.e., an acknowledgement with
146 the sequence number of the packet just sent) the packet just
147 sent should be retransmitted. If no acknowledgement is
148 received within a timeout period, the packet should be
149 retransmitted. This has an unfortunate failure condition on a
150 high-latency line, as a delayed acknowledgement may lead to an
151 endless series of duplicate packets.
153 DATA The actual data bytes follow. The following characters are
154 escaped inline with DLE (ASCII 020, or ^P):
160 The additional DLE characters are not counted in the logical
161 length stored in the TYPE_LEN and LEN1 bytes.
166 These bytes contain an 18 bit checksum of the complete
167 contents of the packet excluding the SEQ byte and the
168 CSUM[123] bytes. The checksum is simply the twos complement
169 addition of all the bytes treated as unsigned characters. The
170 values of the checksum bytes are:
171 CSUM1: 0x40 + ((cksum >> 12) & 0x3f)
172 CSUM2: 0x40 + ((cksum >> 6) & 0x3f)
173 CSUM3: 0x40 + (cksum & 0x3f)
175 It happens that the MIPS remote debugging protocol always
176 communicates with ASCII strings. Because of this, this
177 implementation doesn't bother to handle the DLE quoting mechanism,
178 since it will never be required. */
180 /* The SYN character which starts each packet. */
183 /* The 0x40 used to offset each packet (this value ensures that all of
184 the header and trailer bytes, other than SYN, are printable ASCII
186 #define HDR_OFFSET 0x40
188 /* The indices of the bytes in the packet header. */
189 #define HDR_INDX_SYN 0
190 #define HDR_INDX_TYPE_LEN 1
191 #define HDR_INDX_LEN1 2
192 #define HDR_INDX_SEQ 3
195 /* The data/ack bit in the TYPE_LEN header byte. */
196 #define TYPE_LEN_DA_BIT 0x20
197 #define TYPE_LEN_DATA 0
198 #define TYPE_LEN_ACK TYPE_LEN_DA_BIT
200 /* How to compute the header bytes. */
201 #define HDR_SET_SYN(data, len, seq) (SYN)
202 #define HDR_SET_TYPE_LEN(data, len, seq) \
204 + ((data) ? TYPE_LEN_DATA : TYPE_LEN_ACK) \
205 + (((len) >> 6) & 0x1f))
206 #define HDR_SET_LEN1(data, len, seq) (HDR_OFFSET + ((len) & 0x3f))
207 #define HDR_SET_SEQ(data, len, seq) (HDR_OFFSET + (seq))
209 /* Check that a header byte is reasonable. */
210 #define HDR_CHECK(ch) (((ch) & HDR_OFFSET) == HDR_OFFSET)
212 /* Get data from the header. These macros evaluate their argument
214 #define HDR_IS_DATA(hdr) \
215 (((hdr)[HDR_INDX_TYPE_LEN] & TYPE_LEN_DA_BIT) == TYPE_LEN_DATA)
216 #define HDR_GET_LEN(hdr) \
217 ((((hdr)[HDR_INDX_TYPE_LEN] & 0x1f) << 6) + (((hdr)[HDR_INDX_LEN1] & 0x3f)))
218 #define HDR_GET_SEQ(hdr) ((hdr)[HDR_INDX_SEQ] & 0x3f)
220 /* The maximum data length. */
221 #define DATA_MAXLEN 1023
223 /* The trailer offset. */
224 #define TRLR_OFFSET HDR_OFFSET
226 /* The indices of the bytes in the packet trailer. */
227 #define TRLR_INDX_CSUM1 0
228 #define TRLR_INDX_CSUM2 1
229 #define TRLR_INDX_CSUM3 2
230 #define TRLR_LENGTH 3
232 /* How to compute the trailer bytes. */
233 #define TRLR_SET_CSUM1(cksum) (TRLR_OFFSET + (((cksum) >> 12) & 0x3f))
234 #define TRLR_SET_CSUM2(cksum) (TRLR_OFFSET + (((cksum) >> 6) & 0x3f))
235 #define TRLR_SET_CSUM3(cksum) (TRLR_OFFSET + (((cksum) ) & 0x3f))
237 /* Check that a trailer byte is reasonable. */
238 #define TRLR_CHECK(ch) (((ch) & TRLR_OFFSET) == TRLR_OFFSET)
240 /* Get data from the trailer. This evaluates its argument multiple
242 #define TRLR_GET_CKSUM(trlr) \
243 ((((trlr)[TRLR_INDX_CSUM1] & 0x3f) << 12) \
244 + (((trlr)[TRLR_INDX_CSUM2] & 0x3f) << 6) \
245 + ((trlr)[TRLR_INDX_CSUM3] & 0x3f))
247 /* The sequence number modulos. */
248 #define SEQ_MODULOS (64)
250 /* Set to 1 if the target is open. */
251 static int mips_is_open
;
253 /* Set to 1 while the connection is being initialized. */
254 static int mips_initializing
;
256 /* The next sequence number to send. */
257 static int mips_send_seq
;
259 /* The next sequence number we expect to receive. */
260 static int mips_receive_seq
;
262 /* The time to wait before retransmitting a packet, in seconds. */
263 static int mips_retransmit_wait
= 3;
265 /* The number of times to try retransmitting a packet before giving up. */
266 static int mips_send_retries
= 10;
268 /* The number of garbage characters to accept when looking for an
269 SYN for the next packet. */
270 static int mips_syn_garbage
= 1050;
272 /* The time to wait for a packet, in seconds. */
273 static int mips_receive_wait
= 5;
275 /* Set if we have sent a packet to the board but have not yet received
277 static int mips_need_reply
= 0;
279 /* This can be set to get debugging with ``set remotedebug''. */
280 static int mips_debug
= 0;
282 /* Handle used to access serial I/O stream. */
283 static serial_t mips_desc
;
285 /* Read a character from the remote, aborting on error. Returns
286 SERIAL_TIMEOUT on timeout (since that's what SERIAL_READCHAR
287 returns). FIXME: If we see the string "<IDT>" from the board, then
288 we are debugging on the main console port, and we have somehow
289 dropped out of remote debugging mode. In this case, we
290 automatically go back in to remote debugging mode. This is a hack,
291 put in because I can't find any way for a program running on the
292 remote board to terminate without also ending remote debugging
293 mode. I assume users won't have any trouble with this; for one
294 thing, the IDT documentation generally assumes that the remote
295 debugging port is not the console port. This is, however, very
296 convenient for DejaGnu when you only have one connected serial
300 mips_readchar (timeout
)
304 static int state
= 0;
305 static char nextstate
[5] = { '<', 'I', 'D', 'T', '>' };
307 ch
= SERIAL_READCHAR (mips_desc
, timeout
);
308 if (ch
== SERIAL_EOF
)
309 error ("End of file from remote");
310 if (ch
== SERIAL_ERROR
)
311 error ("Error reading from remote: %s", safe_strerror (errno
));
314 if (ch
!= SERIAL_TIMEOUT
)
315 printf_filtered ("Read '%c' %d 0x%x\n", ch
, ch
, ch
);
317 printf_filtered ("Timed out in read\n");
320 /* If we have seen <IDT> and we either time out, or we see a @
321 (which was echoed from a packet we sent), reset the board as
322 described above. The first character in a packet after the SYN
323 (which is not echoed) is always an @ unless the packet is more
324 than 64 characters long, which ours never are. */
325 if ((ch
== SERIAL_TIMEOUT
|| ch
== '@')
327 && ! mips_initializing
)
330 printf_filtered ("Reinitializing MIPS debugging mode\n");
331 SERIAL_WRITE (mips_desc
, "\rdb tty0\r", sizeof "\rdb tty0\r" - 1);
339 error ("Remote board reset");
342 if (ch
== nextstate
[state
])
350 /* Get a packet header, putting the data in the supplied buffer.
351 PGARBAGE is a pointer to the number of garbage characters received
352 so far. CH is the last character received. Returns 0 for success,
353 or -1 for timeout. */
356 mips_receive_header (hdr
, pgarbage
, ch
, timeout
)
366 /* Wait for a SYN. mips_syn_garbage is intended to prevent
367 sitting here indefinitely if the board sends us one garbage
368 character per second. ch may already have a value from the
369 last time through the loop. */
372 ch
= mips_readchar (timeout
);
373 if (ch
== SERIAL_TIMEOUT
)
377 /* Printing the character here lets the user of gdb see
378 what the program is outputting, if the debugging is
379 being done on the console port. FIXME: Perhaps this
380 should be filtered? */
381 if (! mips_initializing
|| mips_debug
> 0)
388 if (*pgarbage
> mips_syn_garbage
)
389 error ("Remote debugging protocol failure");
393 /* Get the packet header following the SYN. */
394 for (i
= 1; i
< HDR_LENGTH
; i
++)
396 ch
= mips_readchar (timeout
);
397 if (ch
== SERIAL_TIMEOUT
)
400 /* Make sure this is a header byte. */
401 if (ch
== SYN
|| ! HDR_CHECK (ch
))
407 /* If we got the complete header, we can return. Otherwise we
408 loop around and keep looking for SYN. */
414 /* Get a packet header, putting the data in the supplied buffer.
415 PGARBAGE is a pointer to the number of garbage characters received
416 so far. The last character read is returned in *PCH. Returns 0
417 for success, -1 for timeout, -2 for error. */
420 mips_receive_trailer (trlr
, pgarbage
, pch
, timeout
)
429 for (i
= 0; i
< TRLR_LENGTH
; i
++)
431 ch
= mips_readchar (timeout
);
433 if (ch
== SERIAL_TIMEOUT
)
435 if (! TRLR_CHECK (ch
))
442 /* Get the checksum of a packet. HDR points to the packet header.
443 DATA points to the packet data. LEN is the length of DATA. */
446 mips_cksum (hdr
, data
, len
)
447 const unsigned char *hdr
;
448 const unsigned char *data
;
451 register const unsigned char *p
;
457 /* The initial SYN is not included in the checksum. */
471 /* Send a packet containing the given ASCII string. */
474 mips_send_packet (s
, get_ack
)
479 unsigned char *packet
;
484 if (len
> DATA_MAXLEN
)
485 error ("MIPS protocol data packet too long: %s", s
);
487 packet
= (unsigned char *) alloca (HDR_LENGTH
+ len
+ TRLR_LENGTH
+ 1);
489 packet
[HDR_INDX_SYN
] = HDR_SET_SYN (1, len
, mips_send_seq
);
490 packet
[HDR_INDX_TYPE_LEN
] = HDR_SET_TYPE_LEN (1, len
, mips_send_seq
);
491 packet
[HDR_INDX_LEN1
] = HDR_SET_LEN1 (1, len
, mips_send_seq
);
492 packet
[HDR_INDX_SEQ
] = HDR_SET_SEQ (1, len
, mips_send_seq
);
494 memcpy (packet
+ HDR_LENGTH
, s
, len
);
496 cksum
= mips_cksum (packet
, packet
+ HDR_LENGTH
, len
);
497 packet
[HDR_LENGTH
+ len
+ TRLR_INDX_CSUM1
] = TRLR_SET_CSUM1 (cksum
);
498 packet
[HDR_LENGTH
+ len
+ TRLR_INDX_CSUM2
] = TRLR_SET_CSUM2 (cksum
);
499 packet
[HDR_LENGTH
+ len
+ TRLR_INDX_CSUM3
] = TRLR_SET_CSUM3 (cksum
);
501 /* Increment the sequence number. This will set mips_send_seq to
502 the sequence number we expect in the acknowledgement. */
503 mips_send_seq
= (mips_send_seq
+ 1) % SEQ_MODULOS
;
508 /* We can only have one outstanding data packet, so we just wait for
509 the acknowledgement here. Keep retransmitting the packet until
510 we get one, or until we've tried too many times. */
511 for (try = 0; try < mips_send_retries
; try++)
518 packet
[HDR_LENGTH
+ len
+ TRLR_LENGTH
] = '\0';
519 printf_filtered ("Writing \"%s\"\n", packet
+ 1);
522 if (SERIAL_WRITE (mips_desc
, packet
,
523 HDR_LENGTH
+ len
+ TRLR_LENGTH
) != 0)
524 error ("write to target failed: %s", safe_strerror (errno
));
530 unsigned char hdr
[HDR_LENGTH
+ 1];
531 unsigned char trlr
[TRLR_LENGTH
+ 1];
535 /* Get the packet header. If we time out, resend the data
537 err
= mips_receive_header (hdr
, &garbage
, ch
, mips_retransmit_wait
);
543 /* If we get a data packet, assume it is a duplicate and
544 ignore it. FIXME: If the acknowledgement is lost, this
545 data packet may be the packet the remote sends after the
547 if (HDR_IS_DATA (hdr
))
550 /* If the length is not 0, this is a garbled packet. */
551 if (HDR_GET_LEN (hdr
) != 0)
554 /* Get the packet trailer. */
555 err
= mips_receive_trailer (trlr
, &garbage
, &ch
,
556 mips_retransmit_wait
);
558 /* If we timed out, resend the data packet. */
562 /* If we got a bad character, reread the header. */
566 /* If the checksum does not match the trailer checksum, this
567 is a bad packet; ignore it. */
568 if (mips_cksum (hdr
, (unsigned char *) NULL
, 0)
569 != TRLR_GET_CKSUM (trlr
))
574 hdr
[HDR_LENGTH
] = '\0';
575 trlr
[TRLR_LENGTH
] = '\0';
576 printf_filtered ("Got ack %d \"%s%s\"\n",
577 HDR_GET_SEQ (hdr
), hdr
, trlr
);
580 /* If this ack is for the current packet, we're done. */
581 seq
= HDR_GET_SEQ (hdr
);
582 if (seq
== mips_send_seq
)
585 /* If this ack is for the last packet, resend the current
587 if ((seq
+ 1) % SEQ_MODULOS
== mips_send_seq
)
590 /* Otherwise this is a bad ack; ignore it. Increment the
591 garbage count to ensure that we do not stay in this loop
597 error ("Remote did not acknowledge packet");
600 /* Receive and acknowledge a packet, returning the data in BUFF (which
601 should be DATA_MAXLEN + 1 bytes). The protocol documentation
602 implies that only the sender retransmits packets, so this code just
603 waits silently for a packet. It returns the length of the received
607 mips_receive_packet (buff
)
613 unsigned char ack
[HDR_LENGTH
+ TRLR_LENGTH
+ 1];
620 unsigned char hdr
[HDR_LENGTH
];
621 unsigned char trlr
[TRLR_LENGTH
];
625 if (mips_receive_header (hdr
, &garbage
, ch
, mips_receive_wait
) != 0)
626 error ("Timed out waiting for remote packet");
630 /* An acknowledgement is probably a duplicate; ignore it. */
631 if (! HDR_IS_DATA (hdr
))
634 printf_filtered ("Ignoring unexpected ACK\n");
638 /* If this is the wrong sequence number, ignore it. */
639 if (HDR_GET_SEQ (hdr
) != mips_receive_seq
)
642 printf_filtered ("Ignoring sequence number %d (want %d)\n",
643 HDR_GET_SEQ (hdr
), mips_receive_seq
);
647 len
= HDR_GET_LEN (hdr
);
649 for (i
= 0; i
< len
; i
++)
653 rch
= mips_readchar (mips_receive_wait
);
659 if (rch
== SERIAL_TIMEOUT
)
660 error ("Timed out waiting for remote packet");
667 printf_filtered ("Got new SYN after %d chars (wanted %d)\n",
672 err
= mips_receive_trailer (trlr
, &garbage
, &ch
, mips_receive_wait
);
674 error ("Timed out waiting for packet");
678 printf_filtered ("Got SYN when wanted trailer\n");
682 if (mips_cksum (hdr
, buff
, len
) == TRLR_GET_CKSUM (trlr
))
686 printf_filtered ("Bad checksum; data %d, trailer %d\n",
687 mips_cksum (hdr
, buff
, len
),
688 TRLR_GET_CKSUM (trlr
));
690 /* The checksum failed. Send an acknowledgement for the
691 previous packet to tell the remote to resend the packet. */
692 ack
[HDR_INDX_SYN
] = HDR_SET_SYN (0, 0, mips_receive_seq
);
693 ack
[HDR_INDX_TYPE_LEN
] = HDR_SET_TYPE_LEN (0, 0, mips_receive_seq
);
694 ack
[HDR_INDX_LEN1
] = HDR_SET_LEN1 (0, 0, mips_receive_seq
);
695 ack
[HDR_INDX_SEQ
] = HDR_SET_SEQ (0, 0, mips_receive_seq
);
697 cksum
= mips_cksum (ack
, (unsigned char *) NULL
, 0);
699 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM1
] = TRLR_SET_CSUM1 (cksum
);
700 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM2
] = TRLR_SET_CSUM2 (cksum
);
701 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM3
] = TRLR_SET_CSUM3 (cksum
);
705 ack
[HDR_LENGTH
+ TRLR_LENGTH
] = '\0';
706 printf_filtered ("Writing ack %d \"%s\"\n", mips_receive_seq
,
710 if (SERIAL_WRITE (mips_desc
, ack
, HDR_LENGTH
+ TRLR_LENGTH
) != 0)
711 error ("write to target failed: %s", safe_strerror (errno
));
717 printf_filtered ("Got packet \"%s\"\n", buff
);
720 /* We got the packet. Send an acknowledgement. */
721 mips_receive_seq
= (mips_receive_seq
+ 1) % SEQ_MODULOS
;
723 ack
[HDR_INDX_SYN
] = HDR_SET_SYN (0, 0, mips_receive_seq
);
724 ack
[HDR_INDX_TYPE_LEN
] = HDR_SET_TYPE_LEN (0, 0, mips_receive_seq
);
725 ack
[HDR_INDX_LEN1
] = HDR_SET_LEN1 (0, 0, mips_receive_seq
);
726 ack
[HDR_INDX_SEQ
] = HDR_SET_SEQ (0, 0, mips_receive_seq
);
728 cksum
= mips_cksum (ack
, (unsigned char *) NULL
, 0);
730 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM1
] = TRLR_SET_CSUM1 (cksum
);
731 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM2
] = TRLR_SET_CSUM2 (cksum
);
732 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM3
] = TRLR_SET_CSUM3 (cksum
);
736 ack
[HDR_LENGTH
+ TRLR_LENGTH
] = '\0';
737 printf_filtered ("Writing ack %d \"%s\"\n", mips_receive_seq
,
741 if (SERIAL_WRITE (mips_desc
, ack
, HDR_LENGTH
+ TRLR_LENGTH
) != 0)
742 error ("write to target failed: %s", safe_strerror (errno
));
747 /* Optionally send a request to the remote system and optionally wait
748 for the reply. This implements the remote debugging protocol,
749 which is built on top of the packet protocol defined above. Each
750 request has an ADDR argument and a DATA argument. The following
751 requests are defined:
753 \0 don't send a request; just wait for a reply
754 i read word from instruction space at ADDR
755 d read word from data space at ADDR
756 I write DATA to instruction space at ADDR
757 D write DATA to data space at ADDR
758 r read register number ADDR
759 R set register number ADDR to value DATA
760 c continue execution (if ADDR != 1, set pc to ADDR)
761 s single step (if ADDR != 1, set pc to ADDR)
763 The read requests return the value requested. The write requests
764 return the previous value in the changed location. The execution
765 requests return a UNIX wait value (the approximate signal which
766 caused execution to stop is in the upper eight bits).
768 If PERR is not NULL, this function waits for a reply. If an error
769 occurs, it sets *PERR to 1 and sets errno according to what the
770 target board reports. */
773 mips_request (cmd
, addr
, data
, perr
)
779 char buff
[DATA_MAXLEN
+ 1];
789 fatal ("mips_request: Trying to send command before reply");
790 sprintf (buff
, "0x0 %c 0x%x 0x%x", cmd
, addr
, data
);
791 mips_send_packet (buff
, 1);
795 if (perr
== (int *) NULL
)
798 if (! mips_need_reply
)
799 fatal ("mips_request: Trying to get reply before command");
803 len
= mips_receive_packet (buff
);
806 if (sscanf (buff
, "0x%x %c 0x%x 0x%x",
807 &rpid
, &rcmd
, &rerrflg
, &rresponse
) != 4
809 || (cmd
!= '\0' && rcmd
!= cmd
))
810 error ("Bad response from remote board");
816 /* FIXME: This will returns MIPS errno numbers, which may or may
817 not be the same as errno values used on other systems. If
818 they stick to common errno values, they will be the same, but
819 if they don't, they must be translated. */
829 /* Initialize a new connection to the MIPS board, and make sure we are
838 char buff
[DATA_MAXLEN
+ 1];
841 if (mips_initializing
)
844 mips_initializing
= 1;
847 mips_receive_seq
= 0;
849 /* The board seems to want to send us a packet. I don't know what
850 it means. The packet seems to be triggered by a carriage return
851 character, although perhaps any character would do. */
853 SERIAL_WRITE (mips_desc
, &cr
, 1);
855 hold_wait
= mips_receive_wait
;
856 mips_receive_wait
= 3;
859 while (catch_errors (mips_receive_packet
, buff
, (char *) NULL
) == 0)
864 error ("Could not connect to target");
867 /* We did not receive the packet we expected; try resetting the
868 board and trying again. */
869 printf_filtered ("Failed to initialize; trying to reset board\n");
871 SERIAL_WRITE (mips_desc
, &cc
, 1);
873 SERIAL_WRITE (mips_desc
, "\rdb tty0\r", sizeof "\rdb tty0\r" - 1);
876 SERIAL_WRITE (mips_desc
, &cr
, 1);
879 mips_receive_wait
= hold_wait
;
880 mips_initializing
= 0;
882 /* If this doesn't call error, we have connected; we don't care if
883 the request itself succeeds or fails. */
884 mips_request ('r', (unsigned int) 0, (unsigned int) 0, &err
);
887 /* Open a connection to the remote board. */
890 mips_open (name
, from_tty
)
896 "To open a MIPS remote debugging connection, you need to specify what serial\n\
897 device is attached to the target board (e.g., /dev/ttya).");
899 target_preopen (from_tty
);
902 unpush_target (&mips_ops
);
904 mips_desc
= SERIAL_OPEN (name
);
905 if (mips_desc
== (serial_t
) NULL
)
906 perror_with_name (name
);
908 SERIAL_RAW (mips_desc
);
915 printf ("Remote MIPS debugging using %s\n", name
);
916 push_target (&mips_ops
); /* Switch to using remote target now */
918 /* FIXME: Should we call start_remote here? */
921 /* Close a connection to the remote board. */
924 mips_close (quitting
)
933 /* Get the board out of remote debugging mode. */
934 mips_request ('x', (unsigned int) 0, (unsigned int) 0, &err
);
936 SERIAL_CLOSE (mips_desc
);
940 /* Detach from the remote board. */
943 mips_detach (args
, from_tty
)
948 error ("Argument given to \"detach\" when remotely debugging.");
952 printf ("Ending remote MIPS debugging.\n");
955 /* Tell the target board to resume. This does not wait for a reply
959 mips_resume (step
, siggnal
)
963 error ("Can't send signals to a remote system. Try `handle %d ignore'.",
966 mips_request (step
? 's' : 'c',
972 /* Wait until the remote stops, and return a wait status. */
981 /* If we have not sent a single step or continue command, then the
982 board is waiting for us to do something. Return a status
983 indicating that it is stopped. */
984 if (! mips_need_reply
)
986 WSETSTOP (*status
, SIGTRAP
);
990 rstatus
= mips_request ('\0', (unsigned int) 0, (unsigned int) 0, &err
);
992 error ("Remote failure: %s", safe_strerror (errno
));
994 /* FIXME: The target board uses numeric signal values which are
995 those used on MIPS systems. If the host uses different signal
996 values, we need to translate here. I believe all Unix systems
997 use the same values for the signals the board can return, which
998 are: SIGINT, SIGSEGV, SIGBUS, SIGILL, SIGFPE, SIGTRAP. */
1000 /* FIXME: The target board uses a standard Unix wait status int. If
1001 the host system does not, we must translate here. */
1008 /* We have to map between the register numbers used by gdb and the
1009 register numbers used by the debugging protocol. This function
1010 assumes that we are using tm-mips.h. */
1012 #define REGNO_OFFSET 96
1015 mips_map_regno (regno
)
1020 if (regno
>= FP0_REGNUM
&& regno
< FP0_REGNUM
+ 32)
1021 return regno
- FP0_REGNUM
+ 32;
1025 return REGNO_OFFSET
+ 0;
1027 return REGNO_OFFSET
+ 1;
1029 return REGNO_OFFSET
+ 2;
1031 return REGNO_OFFSET
+ 3;
1033 return REGNO_OFFSET
+ 4;
1035 return REGNO_OFFSET
+ 5;
1037 /* FIXME: Is there a way to get the status register? */
1042 /* Fetch the remote registers. */
1045 mips_fetch_registers (regno
)
1053 for (regno
= 0; regno
< NUM_REGS
; regno
++)
1054 mips_fetch_registers (regno
);
1058 val
= mips_request ('r', (unsigned int) mips_map_regno (regno
),
1059 (unsigned int) 0, &err
);
1061 error ("Can't read register %d: %s", regno
, safe_strerror (errno
));
1063 /* We got the number the register holds, but gdb expects to see a
1064 value in the target byte ordering. */
1065 SWAP_TARGET_AND_HOST (val
, sizeof (REGISTER_TYPE
));
1066 supply_register (regno
, (char *) &val
);
1069 /* Prepare to store registers. The MIPS protocol can store individual
1070 registers, so this function doesn't have to do anything. */
1073 mips_prepare_to_store ()
1077 /* Store remote register(s). */
1080 mips_store_registers (regno
)
1087 for (regno
= 0; regno
< NUM_REGS
; regno
++)
1088 mips_store_registers (regno
);
1092 mips_request ('R', (unsigned int) mips_map_regno (regno
),
1093 (unsigned int) read_register (regno
),
1096 error ("Can't write register %d: %s", regno
, safe_strerror (errno
));
1099 /* Fetch a word from the target board. */
1102 mips_fetch_word (addr
)
1108 val
= mips_request ('d', (unsigned int) addr
, (unsigned int) 0, &err
);
1111 /* Data space failed; try instruction space. */
1112 val
= mips_request ('i', (unsigned int) addr
, (unsigned int) 0, &err
);
1114 error ("Can't read address 0x%x: %s", addr
, safe_strerror (errno
));
1119 /* Store a word to the target board. */
1122 mips_store_word (addr
, val
)
1128 mips_request ('D', (unsigned int) addr
, (unsigned int) val
, &err
);
1131 /* Data space failed; try instruction space. */
1132 mips_request ('I', (unsigned int) addr
, (unsigned int) val
, &err
);
1134 error ("Can't write address 0x%x: %s", addr
, safe_strerror (errno
));
1138 /* Read or write LEN bytes from inferior memory at MEMADDR,
1139 transferring to or from debugger address MYADDR. Write to inferior
1140 if SHOULD_WRITE is nonzero. Returns length of data written or
1141 read; 0 for error. Note that protocol gives us the correct value
1142 for a longword, since it transfers values in ASCII. We want the
1143 byte values, so we have to swap the longword values. */
1146 mips_xfer_memory (memaddr
, myaddr
, len
, write
, ignore
)
1151 struct target_ops
*ignore
;
1154 /* Round starting address down to longword boundary. */
1155 register CORE_ADDR addr
= memaddr
&~ 3;
1156 /* Round ending address up; get number of longwords that makes. */
1157 register int count
= (((memaddr
+ len
) - addr
) + 3) / 4;
1158 /* Allocate buffer of that many longwords. */
1159 register unsigned int *buffer
= (unsigned int *) alloca (count
* 4);
1163 /* Fill start and end extra bytes of buffer with existing data. */
1164 if (addr
!= memaddr
|| len
< 4)
1166 /* Need part of initial word -- fetch it. */
1167 buffer
[0] = mips_fetch_word (addr
);
1168 SWAP_TARGET_AND_HOST (buffer
, 4);
1171 if (count
> 1) /* FIXME, avoid if even boundary */
1173 buffer
[count
- 1] = mips_fetch_word (addr
+ (count
- 1) * 4);
1174 SWAP_TARGET_AND_HOST (buffer
+ (count
- 1) * 4, 4);
1177 /* Copy data to be written over corresponding part of buffer */
1179 memcpy ((char *) buffer
+ (memaddr
& 3), myaddr
, len
);
1181 /* Write the entire buffer. */
1183 for (i
= 0; i
< count
; i
++, addr
+= 4)
1185 SWAP_TARGET_AND_HOST (buffer
+ i
, 4);
1186 mips_store_word (addr
, buffer
[i
]);
1191 /* Read all the longwords */
1192 for (i
= 0; i
< count
; i
++, addr
+= 4)
1194 buffer
[i
] = mips_fetch_word (addr
);
1195 SWAP_TARGET_AND_HOST (buffer
+ i
, 4);
1199 /* Copy appropriate bytes out of the buffer. */
1200 memcpy (myaddr
, (char *) buffer
+ (memaddr
& (sizeof (int) - 1)), len
);
1205 /* Print info on this target. */
1208 mips_files_info (ignore
)
1209 struct target_ops
*ignore
;
1211 printf ("Debugging a MIPS board over a serial line.\n");
1214 /* Kill the process running on the board. This will actually only
1215 work if we are doing remote debugging over the console input. I
1216 think that if IDT/sim had the remote debug interrupt enabled on the
1217 right port, we could interrupt the process with a break signal. */
1229 SERIAL_WRITE (mips_desc
, &cc
, 1);
1231 target_mourn_inferior ();
1236 /* Start running on the target board. */
1239 mips_create_inferior (execfile
, args
, env
)
1247 error ("Can't pass arguments to remote MIPS board.");
1249 if (execfile
== 0 || exec_bfd
== 0)
1250 error ("No exec file specified");
1252 entry_pt
= (CORE_ADDR
) bfd_get_start_address (exec_bfd
);
1254 init_wait_for_inferior ();
1256 /* FIXME: Should we set inferior_pid here? */
1258 proceed (entry_pt
, -1, 0);
1261 /* Clean up after a process. Actually nothing to do. */
1264 mips_mourn_inferior ()
1266 unpush_target (&mips_ops
);
1267 generic_mourn_inferior ();
1270 /* The target vector. */
1272 struct target_ops mips_ops
=
1274 "mips", /* to_shortname */
1275 "Remote MIPS debugging over serial line", /* to_longname */
1276 "Debug a board using the MIPS remote debugging protocol over a serial line.\n\
1277 Specify the serial device it is connected to (e.g., /dev/ttya).", /* to_doc */
1278 mips_open
, /* to_open */
1279 mips_close
, /* to_close */
1280 NULL
, /* to_attach */
1281 mips_detach
, /* to_detach */
1282 mips_resume
, /* to_resume */
1283 mips_wait
, /* to_wait */
1284 mips_fetch_registers
, /* to_fetch_registers */
1285 mips_store_registers
, /* to_store_registers */
1286 mips_prepare_to_store
, /* to_prepare_to_store */
1287 mips_xfer_memory
, /* to_xfer_memory */
1288 mips_files_info
, /* to_files_info */
1289 NULL
, /* to_insert_breakpoint */
1290 NULL
, /* to_remove_breakpoint */
1291 NULL
, /* to_terminal_init */
1292 NULL
, /* to_terminal_inferior */
1293 NULL
, /* to_terminal_ours_for_output */
1294 NULL
, /* to_terminal_ours */
1295 NULL
, /* to_terminal_info */
1296 mips_kill
, /* to_kill */
1297 generic_load
, /* to_load */
1298 NULL
, /* to_lookup_symbol */
1299 mips_create_inferior
, /* to_create_inferior */
1300 mips_mourn_inferior
, /* to_mourn_inferior */
1301 NULL
, /* to_can_run */
1302 NULL
, /* to_notice_signals */
1303 process_stratum
, /* to_stratum */
1305 1, /* to_has_all_memory */
1306 1, /* to_has_memory */
1307 1, /* to_has_stack */
1308 1, /* to_has_registers */
1309 1, /* to_has_execution */
1310 NULL
, /* sections */
1311 NULL
, /* sections_end */
1312 OPS_MAGIC
/* to_magic */
1316 _initialize_remote_mips ()
1318 add_target (&mips_ops
);
1321 add_set_cmd ("remotedebug", no_class
, var_zinteger
, (char *) &mips_debug
,
1322 "Set debugging of remote MIPS serial I/O.\n\
1323 When non-zero, each packet sent or received with the remote target\n\
1324 is displayed. Higher numbers produce more debugging.", &setlist
),
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