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. */
33 /* Prototypes for local functions. */
36 mips_readchar
PARAMS ((int timeout
));
39 mips_receive_header
PARAMS ((unsigned char *hdr
, int *pgarbage
, int ch
,
43 mips_receive_trailer
PARAMS ((unsigned char *trlr
, int *pgarbage
, int *pch
,
46 static int mips_cksum
PARAMS ((const unsigned char *hdr
,
47 const unsigned char *data
,
51 mips_send_packet
PARAMS ((const char *s
, int get_ack
));
54 mips_receive_packet
PARAMS ((char *buff
));
57 mips_request
PARAMS ((char cmd
, unsigned int addr
, unsigned int data
,
61 mips_initialize
PARAMS ((void));
64 mips_open
PARAMS ((char *name
, int from_tty
));
67 mips_close
PARAMS ((int quitting
));
70 mips_detach
PARAMS ((char *args
, int from_tty
));
73 mips_resume
PARAMS ((int step
, int siggnal
));
76 mips_wait
PARAMS ((WAITTYPE
*status
));
79 mips_map_regno
PARAMS ((int regno
));
82 mips_fetch_registers
PARAMS ((int regno
));
85 mips_prepare_to_store
PARAMS ((void));
88 mips_store_registers
PARAMS ((int regno
));
91 mips_fetch_word
PARAMS ((CORE_ADDR addr
));
94 mips_store_word
PARAMS ((CORE_ADDR addr
, int value
));
97 mips_xfer_memory
PARAMS ((CORE_ADDR memaddr
, char *myaddr
, int len
,
98 int write
, struct target_ops
*ignore
));
101 mips_files_info
PARAMS ((struct target_ops
*ignore
));
104 mips_load
PARAMS ((char *args
, int from_tty
));
107 mips_create_inferior
PARAMS ((char *execfile
, char *args
, char **env
));
110 mips_mourn_inferior
PARAMS ((void));
112 /* A forward declaration. */
113 extern struct target_ops mips_ops
;
115 /* The MIPS remote debugging interface is built on top of a simple
116 packet protocol. Each packet is organized as follows:
118 SYN The first character is always a SYN (ASCII 026, or ^V). SYN
119 may not appear anywhere else in the packet. Any time a SYN is
120 seen, a new packet should be assumed to have begun.
123 This byte contains the upper five bits of the logical length
124 of the data section, plus a single bit indicating whether this
125 is a data packet or an acknowledgement. The documentation
126 indicates that this bit is 1 for a data packet, but the actual
127 board uses 1 for an acknowledgement. The value of the byte is
128 0x40 + (ack ? 0x20 : 0) + (len >> 6)
129 (we always have 0 <= len < 1024). Acknowledgement packets do
130 not carry data, and must have a data length of 0.
132 LEN1 This byte contains the lower six bits of the logical length of
133 the data section. The value is
136 SEQ This byte contains the six bit sequence number of the packet.
139 An acknowlegment packet contains the sequence number of the
140 packet being acknowledged plus 1 module 64. Data packets are
141 transmitted in sequence. There may only be one outstanding
142 unacknowledged data packet at a time. The sequence numbers
143 are independent in each direction. If an acknowledgement for
144 the previous packet is received (i.e., an acknowledgement with
145 the sequence number of the packet just sent) the packet just
146 sent should be retransmitted. If no acknowledgement is
147 received within a timeout period, the packet should be
148 retransmitted. This has an unfortunate failure condition on a
149 high-latency line, as a delayed acknowledgement may lead to an
150 endless series of duplicate packets.
152 DATA The actual data bytes follow. The following characters are
153 escaped inline with DLE (ASCII 020, or ^P):
159 The additional DLE characters are not counted in the logical
160 length stored in the TYPE_LEN and LEN1 bytes.
165 These bytes contain an 18 bit checksum of the complete
166 contents of the packet excluding the SEQ byte and the
167 CSUM[123] bytes. The checksum is simply the twos complement
168 addition of all the bytes treated as unsigned characters. The
169 values of the checksum bytes are:
170 CSUM1: 0x40 + ((cksum >> 12) & 0x3f)
171 CSUM2: 0x40 + ((cksum >> 6) & 0x3f)
172 CSUM3: 0x40 + (cksum & 0x3f)
174 It happens that the MIPS remote debugging protocol always
175 communicates with ASCII strings. Because of this, this
176 implementation doesn't bother to handle the DLE quoting mechanism,
177 since it will never be required. */
179 /* The SYN character which starts each packet. */
182 /* The 0x40 used to offset each packet (this value ensures that all of
183 the header and trailer bytes, other than SYN, are printable ASCII
185 #define HDR_OFFSET 0x40
187 /* The indices of the bytes in the packet header. */
188 #define HDR_INDX_SYN 0
189 #define HDR_INDX_TYPE_LEN 1
190 #define HDR_INDX_LEN1 2
191 #define HDR_INDX_SEQ 3
194 /* The data/ack bit in the TYPE_LEN header byte. */
195 #define TYPE_LEN_DA_BIT 0x20
196 #define TYPE_LEN_DATA 0
197 #define TYPE_LEN_ACK TYPE_LEN_DA_BIT
199 /* How to compute the header bytes. */
200 #define HDR_SET_SYN(data, len, seq) (SYN)
201 #define HDR_SET_TYPE_LEN(data, len, seq) \
203 + ((data) ? TYPE_LEN_DATA : TYPE_LEN_ACK) \
204 + (((len) >> 6) & 0x1f))
205 #define HDR_SET_LEN1(data, len, seq) (HDR_OFFSET + ((len) & 0x3f))
206 #define HDR_SET_SEQ(data, len, seq) (HDR_OFFSET + (seq))
208 /* Check that a header byte is reasonable. */
209 #define HDR_CHECK(ch) (((ch) & HDR_OFFSET) == HDR_OFFSET)
211 /* Get data from the header. These macros evaluate their argument
213 #define HDR_IS_DATA(hdr) \
214 (((hdr)[HDR_INDX_TYPE_LEN] & TYPE_LEN_DA_BIT) == TYPE_LEN_DATA)
215 #define HDR_GET_LEN(hdr) \
216 ((((hdr)[HDR_INDX_TYPE_LEN] & 0x1f) << 6) + (((hdr)[HDR_INDX_LEN1] & 0x3f)))
217 #define HDR_GET_SEQ(hdr) ((hdr)[HDR_INDX_SEQ] & 0x3f)
219 /* The maximum data length. */
220 #define DATA_MAXLEN 1023
222 /* The trailer offset. */
223 #define TRLR_OFFSET HDR_OFFSET
225 /* The indices of the bytes in the packet trailer. */
226 #define TRLR_INDX_CSUM1 0
227 #define TRLR_INDX_CSUM2 1
228 #define TRLR_INDX_CSUM3 2
229 #define TRLR_LENGTH 3
231 /* How to compute the trailer bytes. */
232 #define TRLR_SET_CSUM1(cksum) (TRLR_OFFSET + (((cksum) >> 12) & 0x3f))
233 #define TRLR_SET_CSUM2(cksum) (TRLR_OFFSET + (((cksum) >> 6) & 0x3f))
234 #define TRLR_SET_CSUM3(cksum) (TRLR_OFFSET + (((cksum) ) & 0x3f))
236 /* Check that a trailer byte is reasonable. */
237 #define TRLR_CHECK(ch) (((ch) & TRLR_OFFSET) == TRLR_OFFSET)
239 /* Get data from the trailer. This evaluates its argument multiple
241 #define TRLR_GET_CKSUM(trlr) \
242 ((((trlr)[TRLR_INDX_CSUM1] & 0x3f) << 12) \
243 + (((trlr)[TRLR_INDX_CSUM2] & 0x3f) << 6) \
244 + ((trlr)[TRLR_INDX_CSUM3] & 0x3f))
246 /* The sequence number modulos. */
247 #define SEQ_MODULOS (64)
249 /* Set to 1 if the target is open. */
250 static int mips_is_open
;
252 /* Set to 1 while the connection is being initialized. */
253 static int mips_initializing
;
255 /* The next sequence number to send. */
256 static int mips_send_seq
;
258 /* The next sequence number we expect to receive. */
259 static int mips_receive_seq
;
261 /* The time to wait before retransmitting a packet, in seconds. */
262 static int mips_retransmit_wait
= 3;
264 /* The number of times to try retransmitting a packet before giving up. */
265 static int mips_send_retries
= 10;
267 /* The number of garbage characters to accept when looking for an
268 SYN for the next packet. */
269 static int mips_syn_garbage
= 1050;
271 /* The time to wait for a packet, in seconds. */
272 static int mips_receive_wait
= 5;
274 /* Set if we have sent a packet to the board but have not yet received
276 static int mips_need_reply
= 0;
278 /* This can be set to get debugging with ``set remotedebug''. */
279 static int mips_debug
= 0;
281 /* Handle used to access serial I/O stream. */
282 static serial_t mips_desc
;
284 /* Read a character from the remote, aborting on error. Returns
285 SERIAL_TIMEOUT on timeout (since that's what SERIAL_READCHAR
286 returns). FIXME: If we see the string "<IDT>" from the board, then
287 we are debugging on the main console port, and we have somehow
288 dropped out of remote debugging mode. In this case, we
289 automatically go back in to remote debugging mode. This is a hack,
290 put in because I can't find any way for a program running on the
291 remote board to terminate without also ending remote debugging
292 mode. I assume users won't have any trouble with this; for one
293 thing, the IDT documentation generally assumes that the remote
294 debugging port is not the console port. This is, however, very
295 convenient for DejaGnu when you only have one connected serial
299 mips_readchar (timeout
)
303 static int state
= 0;
304 static char nextstate
[5] = { '<', 'I', 'D', 'T', '>' };
306 ch
= SERIAL_READCHAR (mips_desc
, timeout
);
307 if (ch
== SERIAL_EOF
)
308 error ("End of file from remote");
309 if (ch
== SERIAL_ERROR
)
310 error ("Error reading from remote: %s", safe_strerror (errno
));
313 if (ch
!= SERIAL_TIMEOUT
)
314 printf_filtered ("Read '%c' %d 0x%x\n", ch
, ch
, ch
);
316 printf_filtered ("Timed out in read\n");
319 /* If we have seen <IDT> and we either time out, or we see a @
320 (which was echoed from a packet we sent), reset the board as
321 described above. The first character in a packet after the SYN
322 (which is not echoed) is always an @ unless the packet is more
323 than 64 characters long, which ours never are. */
324 if ((ch
== SERIAL_TIMEOUT
|| ch
== '@')
326 && ! mips_initializing
)
329 printf_filtered ("Reinitializing MIPS debugging mode\n");
330 SERIAL_WRITE (mips_desc
, "\rdb tty0\r", sizeof "\rdb tty0\r" - 1);
338 error ("Remote board reset");
341 if (ch
== nextstate
[state
])
349 /* Get a packet header, putting the data in the supplied buffer.
350 PGARBAGE is a pointer to the number of garbage characters received
351 so far. CH is the last character received. Returns 0 for success,
352 or -1 for timeout. */
355 mips_receive_header (hdr
, pgarbage
, ch
, timeout
)
365 /* Wait for a SYN. mips_syn_garbage is intended to prevent
366 sitting here indefinitely if the board sends us one garbage
367 character per second. ch may already have a value from the
368 last time through the loop. */
371 ch
= mips_readchar (timeout
);
372 if (ch
== SERIAL_TIMEOUT
)
376 /* Printing the character here lets the user of gdb see
377 what the program is outputting, if the debugging is
378 being done on the console port. FIXME: Perhaps this
379 should be filtered? */
380 if (! mips_initializing
|| mips_debug
> 0)
387 if (*pgarbage
> mips_syn_garbage
)
388 error ("Remote debugging protocol failure");
392 /* Get the packet header following the SYN. */
393 for (i
= 1; i
< HDR_LENGTH
; i
++)
395 ch
= mips_readchar (timeout
);
396 if (ch
== SERIAL_TIMEOUT
)
399 /* Make sure this is a header byte. */
400 if (ch
== SYN
|| ! HDR_CHECK (ch
))
406 /* If we got the complete header, we can return. Otherwise we
407 loop around and keep looking for SYN. */
413 /* Get a packet header, putting the data in the supplied buffer.
414 PGARBAGE is a pointer to the number of garbage characters received
415 so far. The last character read is returned in *PCH. Returns 0
416 for success, -1 for timeout, -2 for error. */
419 mips_receive_trailer (trlr
, pgarbage
, pch
, timeout
)
428 for (i
= 0; i
< TRLR_LENGTH
; i
++)
430 ch
= mips_readchar (timeout
);
432 if (ch
== SERIAL_TIMEOUT
)
434 if (! TRLR_CHECK (ch
))
441 /* Get the checksum of a packet. HDR points to the packet header.
442 DATA points to the packet data. LEN is the length of DATA. */
445 mips_cksum (hdr
, data
, len
)
446 const unsigned char *hdr
;
447 const unsigned char *data
;
450 register const unsigned char *p
;
456 /* The initial SYN is not included in the checksum. */
470 /* Send a packet containing the given ASCII string. */
473 mips_send_packet (s
, get_ack
)
478 unsigned char *packet
;
483 if (len
> DATA_MAXLEN
)
484 error ("MIPS protocol data packet too long: %s", s
);
486 packet
= (unsigned char *) alloca (HDR_LENGTH
+ len
+ TRLR_LENGTH
+ 1);
488 packet
[HDR_INDX_SYN
] = HDR_SET_SYN (1, len
, mips_send_seq
);
489 packet
[HDR_INDX_TYPE_LEN
] = HDR_SET_TYPE_LEN (1, len
, mips_send_seq
);
490 packet
[HDR_INDX_LEN1
] = HDR_SET_LEN1 (1, len
, mips_send_seq
);
491 packet
[HDR_INDX_SEQ
] = HDR_SET_SEQ (1, len
, mips_send_seq
);
493 memcpy (packet
+ HDR_LENGTH
, s
, len
);
495 cksum
= mips_cksum (packet
, packet
+ HDR_LENGTH
, len
);
496 packet
[HDR_LENGTH
+ len
+ TRLR_INDX_CSUM1
] = TRLR_SET_CSUM1 (cksum
);
497 packet
[HDR_LENGTH
+ len
+ TRLR_INDX_CSUM2
] = TRLR_SET_CSUM2 (cksum
);
498 packet
[HDR_LENGTH
+ len
+ TRLR_INDX_CSUM3
] = TRLR_SET_CSUM3 (cksum
);
500 /* Increment the sequence number. This will set mips_send_seq to
501 the sequence number we expect in the acknowledgement. */
502 mips_send_seq
= (mips_send_seq
+ 1) % SEQ_MODULOS
;
507 /* We can only have one outstanding data packet, so we just wait for
508 the acknowledgement here. Keep retransmitting the packet until
509 we get one, or until we've tried too many times. */
510 for (try = 0; try < mips_send_retries
; try++)
517 packet
[HDR_LENGTH
+ len
+ TRLR_LENGTH
] = '\0';
518 printf_filtered ("Writing \"%s\"\n", packet
+ 1);
521 if (SERIAL_WRITE (mips_desc
, packet
,
522 HDR_LENGTH
+ len
+ TRLR_LENGTH
) != 0)
523 error ("write to target failed: %s", safe_strerror (errno
));
529 unsigned char hdr
[HDR_LENGTH
+ 1];
530 unsigned char trlr
[TRLR_LENGTH
+ 1];
534 /* Get the packet header. If we time out, resend the data
536 err
= mips_receive_header (hdr
, &garbage
, ch
, mips_retransmit_wait
);
542 /* If we get a data packet, assume it is a duplicate and
543 ignore it. FIXME: If the acknowledgement is lost, this
544 data packet may be the packet the remote sends after the
546 if (HDR_IS_DATA (hdr
))
549 /* If the length is not 0, this is a garbled packet. */
550 if (HDR_GET_LEN (hdr
) != 0)
553 /* Get the packet trailer. */
554 err
= mips_receive_trailer (trlr
, &garbage
, &ch
,
555 mips_retransmit_wait
);
557 /* If we timed out, resend the data packet. */
561 /* If we got a bad character, reread the header. */
565 /* If the checksum does not match the trailer checksum, this
566 is a bad packet; ignore it. */
567 if (mips_cksum (hdr
, (unsigned char *) NULL
, 0)
568 != TRLR_GET_CKSUM (trlr
))
573 hdr
[HDR_LENGTH
] = '\0';
574 trlr
[TRLR_LENGTH
] = '\0';
575 printf_filtered ("Got ack %d \"%s%s\"\n",
576 HDR_GET_SEQ (hdr
), hdr
, trlr
);
579 /* If this ack is for the current packet, we're done. */
580 seq
= HDR_GET_SEQ (hdr
);
581 if (seq
== mips_send_seq
)
584 /* If this ack is for the last packet, resend the current
586 if ((seq
+ 1) % SEQ_MODULOS
== mips_send_seq
)
589 /* Otherwise this is a bad ack; ignore it. Increment the
590 garbage count to ensure that we do not stay in this loop
596 error ("Remote did not acknowledge packet");
599 /* Receive and acknowledge a packet, returning the data in BUFF (which
600 should be DATA_MAXLEN + 1 bytes). The protocol documentation
601 implies that only the sender retransmits packets, so this code just
602 waits silently for a packet. It returns the length of the received
606 mips_receive_packet (buff
)
612 unsigned char ack
[HDR_LENGTH
+ TRLR_LENGTH
+ 1];
619 unsigned char hdr
[HDR_LENGTH
];
620 unsigned char trlr
[TRLR_LENGTH
];
624 if (mips_receive_header (hdr
, &garbage
, ch
, mips_receive_wait
) != 0)
625 error ("Timed out waiting for remote packet");
629 /* An acknowledgement is probably a duplicate; ignore it. */
630 if (! HDR_IS_DATA (hdr
))
633 printf_filtered ("Ignoring unexpected ACK\n");
637 /* If this is the wrong sequence number, ignore it. */
638 if (HDR_GET_SEQ (hdr
) != mips_receive_seq
)
641 printf_filtered ("Ignoring sequence number %d (want %d)\n",
642 HDR_GET_SEQ (hdr
), mips_receive_seq
);
646 len
= HDR_GET_LEN (hdr
);
648 for (i
= 0; i
< len
; i
++)
652 rch
= mips_readchar (mips_receive_wait
);
658 if (rch
== SERIAL_TIMEOUT
)
659 error ("Timed out waiting for remote packet");
666 printf_filtered ("Got new SYN after %d chars (wanted %d)\n",
671 err
= mips_receive_trailer (trlr
, &garbage
, &ch
, mips_receive_wait
);
673 error ("Timed out waiting for packet");
677 printf_filtered ("Got SYN when wanted trailer\n");
681 if (mips_cksum (hdr
, buff
, len
) == TRLR_GET_CKSUM (trlr
))
685 printf_filtered ("Bad checksum; data %d, trailer %d\n",
686 mips_cksum (hdr
, buff
, len
),
687 TRLR_GET_CKSUM (trlr
));
689 /* The checksum failed. Send an acknowledgement for the
690 previous packet to tell the remote to resend the packet. */
691 ack
[HDR_INDX_SYN
] = HDR_SET_SYN (0, 0, mips_receive_seq
);
692 ack
[HDR_INDX_TYPE_LEN
] = HDR_SET_TYPE_LEN (0, 0, mips_receive_seq
);
693 ack
[HDR_INDX_LEN1
] = HDR_SET_LEN1 (0, 0, mips_receive_seq
);
694 ack
[HDR_INDX_SEQ
] = HDR_SET_SEQ (0, 0, mips_receive_seq
);
696 cksum
= mips_cksum (ack
, (unsigned char *) NULL
, 0);
698 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM1
] = TRLR_SET_CSUM1 (cksum
);
699 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM2
] = TRLR_SET_CSUM2 (cksum
);
700 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM3
] = TRLR_SET_CSUM3 (cksum
);
704 ack
[HDR_LENGTH
+ TRLR_LENGTH
] = '\0';
705 printf_filtered ("Writing ack %d \"%s\"\n", mips_receive_seq
,
709 if (SERIAL_WRITE (mips_desc
, ack
, HDR_LENGTH
+ TRLR_LENGTH
) != 0)
710 error ("write to target failed: %s", safe_strerror (errno
));
716 printf_filtered ("Got packet \"%s\"\n", buff
);
719 /* We got the packet. Send an acknowledgement. */
720 mips_receive_seq
= (mips_receive_seq
+ 1) % SEQ_MODULOS
;
722 ack
[HDR_INDX_SYN
] = HDR_SET_SYN (0, 0, mips_receive_seq
);
723 ack
[HDR_INDX_TYPE_LEN
] = HDR_SET_TYPE_LEN (0, 0, mips_receive_seq
);
724 ack
[HDR_INDX_LEN1
] = HDR_SET_LEN1 (0, 0, mips_receive_seq
);
725 ack
[HDR_INDX_SEQ
] = HDR_SET_SEQ (0, 0, mips_receive_seq
);
727 cksum
= mips_cksum (ack
, (unsigned char *) NULL
, 0);
729 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM1
] = TRLR_SET_CSUM1 (cksum
);
730 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM2
] = TRLR_SET_CSUM2 (cksum
);
731 ack
[HDR_LENGTH
+ TRLR_INDX_CSUM3
] = TRLR_SET_CSUM3 (cksum
);
735 ack
[HDR_LENGTH
+ TRLR_LENGTH
] = '\0';
736 printf_filtered ("Writing ack %d \"%s\"\n", mips_receive_seq
,
740 if (SERIAL_WRITE (mips_desc
, ack
, HDR_LENGTH
+ TRLR_LENGTH
) != 0)
741 error ("write to target failed: %s", safe_strerror (errno
));
746 /* Optionally send a request to the remote system and optionally wait
747 for the reply. This implements the remote debugging protocol,
748 which is built on top of the packet protocol defined above. Each
749 request has an ADDR argument and a DATA argument. The following
750 requests are defined:
752 \0 don't send a request; just wait for a reply
753 i read word from instruction space at ADDR
754 d read word from data space at ADDR
755 I write DATA to instruction space at ADDR
756 D write DATA to data space at ADDR
757 r read register number ADDR
758 R set register number ADDR to value DATA
759 c continue execution (if ADDR != 1, set pc to ADDR)
760 s single step (if ADDR != 1, set pc to ADDR)
762 The read requests return the value requested. The write requests
763 return the previous value in the changed location. The execution
764 requests return a UNIX wait value (the approximate signal which
765 caused execution to stop is in the upper eight bits).
767 If PERR is not NULL, this function waits for a reply. If an error
768 occurs, it sets *PERR to 1 and sets errno according to what the
769 target board reports. */
772 mips_request (cmd
, addr
, data
, perr
)
778 char buff
[DATA_MAXLEN
+ 1];
788 fatal ("mips_request: Trying to send command before reply");
789 sprintf (buff
, "0x0 %c 0x%x 0x%x", cmd
, addr
, data
);
790 mips_send_packet (buff
, 1);
794 if (perr
== (int *) NULL
)
797 if (! mips_need_reply
)
798 fatal ("mips_request: Trying to get reply before command");
802 len
= mips_receive_packet (buff
);
805 if (sscanf (buff
, "0x%x %c 0x%x 0x%x",
806 &rpid
, &rcmd
, &rerrflg
, &rresponse
) != 4
808 || (cmd
!= '\0' && rcmd
!= cmd
))
809 error ("Bad response from remote board");
815 /* FIXME: This will returns MIPS errno numbers, which may or may
816 not be the same as errno values used on other systems. If
817 they stick to common errno values, they will be the same, but
818 if they don't, they must be translated. */
828 /* Initialize a new connection to the MIPS board, and make sure we are
837 char buff
[DATA_MAXLEN
+ 1];
840 if (mips_initializing
)
843 mips_initializing
= 1;
846 mips_receive_seq
= 0;
848 /* The board seems to want to send us a packet. I don't know what
849 it means. The packet seems to be triggered by a carriage return
850 character, although perhaps any character would do. */
852 SERIAL_WRITE (mips_desc
, &cr
, 1);
854 hold_wait
= mips_receive_wait
;
855 mips_receive_wait
= 3;
858 while (catch_errors (mips_receive_packet
, buff
, (char *) NULL
) == 0)
863 error ("Could not connect to target");
866 /* We did not receive the packet we expected; try resetting the
867 board and trying again. */
868 printf_filtered ("Failed to initialize; trying to reset board\n");
870 SERIAL_WRITE (mips_desc
, &cc
, 1);
872 SERIAL_WRITE (mips_desc
, "\rdb tty0\r", sizeof "\rdb tty0\r" - 1);
875 SERIAL_WRITE (mips_desc
, &cr
, 1);
878 mips_receive_wait
= hold_wait
;
879 mips_initializing
= 0;
881 /* If this doesn't call error, we have connected; we don't care if
882 the request itself succeeds or fails. */
883 mips_request ('r', (unsigned int) 0, (unsigned int) 0, &err
);
886 /* Open a connection to the remote board. */
889 mips_open (name
, from_tty
)
895 "To open a MIPS remote debugging connection, you need to specify what serial\n\
896 device is attached to the target board (e.g., /dev/ttya).");
898 target_preopen (from_tty
);
901 unpush_target (&mips_ops
);
903 mips_desc
= SERIAL_OPEN (name
);
904 if (mips_desc
== (serial_t
) NULL
)
905 perror_with_name (name
);
907 SERIAL_RAW (mips_desc
);
914 printf ("Remote MIPS debugging using %s\n", name
);
915 push_target (&mips_ops
); /* Switch to using remote target now */
917 /* FIXME: Should we call start_remote here? */
920 /* Close a connection to the remote board. */
923 mips_close (quitting
)
932 /* Get the board out of remote debugging mode. */
933 mips_request ('x', (unsigned int) 0, (unsigned int) 0, &err
);
935 SERIAL_CLOSE (mips_desc
);
939 /* Detach from the remote board. */
942 mips_detach (args
, from_tty
)
947 error ("Argument given to \"detach\" when remotely debugging.");
951 printf ("Ending remote MIPS debugging.\n");
954 /* Tell the target board to resume. This does not wait for a reply
958 mips_resume (step
, siggnal
)
962 error ("Can't send signals to a remote system. Try `handle %d ignore'.",
965 mips_request (step
? 's' : 'c',
971 /* Wait until the remote stops, and return a wait status. */
980 /* If we have not sent a single step or continue command, then the
981 board is waiting for us to do something. Return a status
982 indicating that it is stopped. */
983 if (! mips_need_reply
)
985 WSETSTOP (*status
, SIGTRAP
);
989 rstatus
= mips_request ('\0', (unsigned int) 0, (unsigned int) 0, &err
);
991 error ("Remote failure: %s", safe_strerror (errno
));
993 /* FIXME: The target board uses numeric signal values which are
994 those used on MIPS systems. If the host uses different signal
995 values, we need to translate here. I believe all Unix systems
996 use the same values for the signals the board can return, which
997 are: SIGINT, SIGSEGV, SIGBUS, SIGILL, SIGFPE, SIGTRAP. */
999 /* FIXME: The target board uses a standard Unix wait status int. If
1000 the host system does not, we must translate here. */
1007 /* We have to map between the register numbers used by gdb and the
1008 register numbers used by the debugging protocol. This function
1009 assumes that we are using tm-mips.h. */
1011 #define REGNO_OFFSET 96
1014 mips_map_regno (regno
)
1019 if (regno
>= FP0_REGNUM
&& regno
< FP0_REGNUM
+ 32)
1020 return regno
- FP0_REGNUM
+ 32;
1024 return REGNO_OFFSET
+ 0;
1026 return REGNO_OFFSET
+ 1;
1028 return REGNO_OFFSET
+ 2;
1030 return REGNO_OFFSET
+ 3;
1032 return REGNO_OFFSET
+ 4;
1034 return REGNO_OFFSET
+ 5;
1036 /* FIXME: Is there a way to get the status register? */
1041 /* Fetch the remote registers. */
1044 mips_fetch_registers (regno
)
1052 for (regno
= 0; regno
< NUM_REGS
; regno
++)
1053 mips_fetch_registers (regno
);
1057 val
= mips_request ('r', (unsigned int) mips_map_regno (regno
),
1058 (unsigned int) 0, &err
);
1060 error ("Can't read register %d: %s", regno
, safe_strerror (errno
));
1062 /* We got the number the register holds, but gdb expects to see a
1063 value in the target byte ordering. */
1064 SWAP_TARGET_AND_HOST (val
, sizeof (REGISTER_TYPE
));
1065 supply_register (regno
, (char *) &val
);
1068 /* Prepare to store registers. The MIPS protocol can store individual
1069 registers, so this function doesn't have to do anything. */
1072 mips_prepare_to_store ()
1076 /* Store remote register(s). */
1079 mips_store_registers (regno
)
1086 for (regno
= 0; regno
< NUM_REGS
; regno
++)
1087 mips_store_registers (regno
);
1091 mips_request ('R', (unsigned int) mips_map_regno (regno
),
1092 (unsigned int) read_register (regno
),
1095 error ("Can't write register %d: %s", regno
, safe_strerror (errno
));
1098 /* Fetch a word from the target board. */
1101 mips_fetch_word (addr
)
1107 val
= mips_request ('d', (unsigned int) addr
, (unsigned int) 0, &err
);
1110 /* Data space failed; try instruction space. */
1111 val
= mips_request ('i', (unsigned int) addr
, (unsigned int) 0, &err
);
1113 error ("Can't read address 0x%x: %s", addr
, safe_strerror (errno
));
1118 /* Store a word to the target board. */
1121 mips_store_word (addr
, val
)
1127 mips_request ('D', (unsigned int) addr
, (unsigned int) val
, &err
);
1130 /* Data space failed; try instruction space. */
1131 mips_request ('I', (unsigned int) addr
, (unsigned int) val
, &err
);
1133 error ("Can't write address 0x%x: %s", addr
, safe_strerror (errno
));
1137 /* Read or write LEN bytes from inferior memory at MEMADDR,
1138 transferring to or from debugger address MYADDR. Write to inferior
1139 if SHOULD_WRITE is nonzero. Returns length of data written or
1140 read; 0 for error. Note that protocol gives us the correct value
1141 for a longword, since it transfers values in ASCII. We want the
1142 byte values, so we have to swap the longword values. */
1145 mips_xfer_memory (memaddr
, myaddr
, len
, write
, ignore
)
1150 struct target_ops
*ignore
;
1153 /* Round starting address down to longword boundary. */
1154 register CORE_ADDR addr
= memaddr
&~ 3;
1155 /* Round ending address up; get number of longwords that makes. */
1156 register int count
= (((memaddr
+ len
) - addr
) + 3) / 4;
1157 /* Allocate buffer of that many longwords. */
1158 register unsigned int *buffer
= (unsigned int *) alloca (count
* 4);
1162 /* Fill start and end extra bytes of buffer with existing data. */
1163 if (addr
!= memaddr
|| len
< 4)
1165 /* Need part of initial word -- fetch it. */
1166 buffer
[0] = mips_fetch_word (addr
);
1167 SWAP_TARGET_AND_HOST (buffer
, 4);
1170 if (count
> 1) /* FIXME, avoid if even boundary */
1172 buffer
[count
- 1] = mips_fetch_word (addr
+ (count
- 1) * 4);
1173 SWAP_TARGET_AND_HOST (buffer
+ (count
- 1) * 4, 4);
1176 /* Copy data to be written over corresponding part of buffer */
1178 memcpy ((char *) buffer
+ (memaddr
& 3), myaddr
, len
);
1180 /* Write the entire buffer. */
1182 for (i
= 0; i
< count
; i
++, addr
+= 4)
1184 SWAP_TARGET_AND_HOST (buffer
+ i
, 4);
1185 mips_store_word (addr
, buffer
[i
]);
1190 /* Read all the longwords */
1191 for (i
= 0; i
< count
; i
++, addr
+= 4)
1193 buffer
[i
] = mips_fetch_word (addr
);
1194 SWAP_TARGET_AND_HOST (buffer
+ i
, 4);
1198 /* Copy appropriate bytes out of the buffer. */
1199 memcpy (myaddr
, (char *) buffer
+ (memaddr
& (sizeof (int) - 1)), len
);
1204 /* Print info on this target. */
1207 mips_files_info (ignore
)
1208 struct target_ops
*ignore
;
1210 printf ("Debugging a MIPS board over a serial line.\n");
1213 /* Kill the process running on the board. This will actually only
1214 work if we are doing remote debugging over the console input. I
1215 think that if IDT/sim had the remote debug interrupt enabled on the
1216 right port, we could interrupt the process with a break signal. */
1228 SERIAL_WRITE (mips_desc
, &cc
, 1);
1230 target_mourn_inferior ();
1235 /* Load an executable onto the board. */
1238 mips_load (args
, from_tty
)
1247 abfd
= bfd_openr (args
, 0);
1248 if (abfd
== (bfd
*) NULL
)
1249 error ("Unable to open file %s", args
);
1251 if (bfd_check_format (abfd
, bfd_object
) == 0)
1252 error ("%s: Not an object file", args
);
1255 for (s
= abfd
->sections
; s
!= (asection
*) NULL
; s
= s
->next
)
1257 if ((s
->flags
& SEC_LOAD
) != 0)
1261 size
= bfd_get_section_size_before_reloc (s
);
1265 struct cleanup
*old_chain
;
1268 buffer
= xmalloc (size
);
1269 old_chain
= make_cleanup (free
, buffer
);
1271 vma
= bfd_get_section_vma (abfd
, s
);
1272 printf_filtered ("Loading section %s, size 0x%x vma 0x%x\n",
1273 bfd_get_section_name (abfd
, s
), size
, vma
);
1274 bfd_get_section_contents (abfd
, s
, buffer
, 0, size
);
1275 mips_xfer_memory (vma
, buffer
, size
, 1, &mips_ops
);
1277 do_cleanups (old_chain
);
1279 if ((bfd_get_section_flags (abfd
, s
) & SEC_CODE
) != 0
1286 mips_request ('R', (unsigned int) mips_map_regno (PC_REGNUM
),
1287 (unsigned int) abfd
->start_address
,
1290 error ("Can't write PC register: %s", safe_strerror (errno
));
1294 /* FIXME: Should we call symbol_file_add here? The local variable
1295 text exists just for this call. Making the call seems to confuse
1296 gdb if more than one file is loaded in. Perhaps passing MAINLINE
1297 as 1 would fix this, but it's not clear that that is correct
1298 either since it is possible to load several files onto the board.
1300 symbol_file_add (args, from_tty, text, 0, 0, 0); */
1303 /* Start running on the target board. */
1306 mips_create_inferior (execfile
, args
, env
)
1314 error ("Can't pass arguments to remote MIPS board.");
1316 if (execfile
== 0 || exec_bfd
== 0)
1317 error ("No exec file specified");
1319 entry_pt
= (CORE_ADDR
) bfd_get_start_address (exec_bfd
);
1321 init_wait_for_inferior ();
1323 /* FIXME: Should we set inferior_pid here? */
1325 proceed (entry_pt
, -1, 0);
1328 /* Clean up after a process. Actually nothing to do. */
1331 mips_mourn_inferior ()
1333 unpush_target (&mips_ops
);
1334 generic_mourn_inferior ();
1337 /* The target vector. */
1339 struct target_ops mips_ops
=
1341 "mips", /* to_shortname */
1342 "Remote MIPS debugging over serial line", /* to_longname */
1343 "Debug a board using the MIPS remote debugging protocol over a serial line.\n\
1344 Specify the serial device it is connected to (e.g., /dev/ttya).", /* to_doc */
1345 mips_open
, /* to_open */
1346 mips_close
, /* to_close */
1347 NULL
, /* to_attach */
1348 mips_detach
, /* to_detach */
1349 mips_resume
, /* to_resume */
1350 mips_wait
, /* to_wait */
1351 mips_fetch_registers
, /* to_fetch_registers */
1352 mips_store_registers
, /* to_store_registers */
1353 mips_prepare_to_store
, /* to_prepare_to_store */
1354 mips_xfer_memory
, /* to_xfer_memory */
1355 mips_files_info
, /* to_files_info */
1356 NULL
, /* to_insert_breakpoint */
1357 NULL
, /* to_remove_breakpoint */
1358 NULL
, /* to_terminal_init */
1359 NULL
, /* to_terminal_inferior */
1360 NULL
, /* to_terminal_ours_for_output */
1361 NULL
, /* to_terminal_ours */
1362 NULL
, /* to_terminal_info */
1363 mips_kill
, /* to_kill */
1364 mips_load
, /* to_load */
1365 NULL
, /* to_lookup_symbol */
1366 mips_create_inferior
, /* to_create_inferior */
1367 mips_mourn_inferior
, /* to_mourn_inferior */
1368 NULL
, /* to_can_run */
1369 NULL
, /* to_notice_signals */
1370 process_stratum
, /* to_stratum */
1372 1, /* to_has_all_memory */
1373 1, /* to_has_memory */
1374 1, /* to_has_stack */
1375 1, /* to_has_registers */
1376 1, /* to_has_execution */
1377 NULL
, /* sections */
1378 NULL
, /* sections_end */
1379 OPS_MAGIC
/* to_magic */
1383 _initialize_remote_mips ()
1385 add_target (&mips_ops
);
1388 add_set_cmd ("remotedebug", no_class
, var_zinteger
, (char *) &mips_debug
,
1389 "Set debugging of remote MIPS serial I/O.\n\
1390 When non-zero, each packet sent or received with the remote target\n\
1391 is displayed. Higher numbers produce more debugging.", &setlist
),
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