1543 lines
43 KiB
C
1543 lines
43 KiB
C
/* Remote debugging interface for MIPS remote debugging protocol.
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Copyright 1993, 1994 Free Software Foundation, Inc.
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Contributed by Cygnus Support. Written by Ian Lance Taylor
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<ian@cygnus.com>.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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#include "defs.h"
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#include "inferior.h"
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#include "bfd.h"
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#include "symfile.h"
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#include "wait.h"
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#include "gdbcmd.h"
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#include "gdbcore.h"
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#include "serial.h"
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#include "target.h"
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#include "remote-utils.h"
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#include <signal.h>
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#include <varargs.h>
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/* Prototypes for local functions. */
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static int
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mips_readchar PARAMS ((int timeout));
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static int
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mips_receive_header PARAMS ((unsigned char *hdr, int *pgarbage, int ch,
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int timeout));
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static int
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mips_receive_trailer PARAMS ((unsigned char *trlr, int *pgarbage, int *pch,
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int timeout));
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static int mips_cksum PARAMS ((const unsigned char *hdr,
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const unsigned char *data,
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int len));
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static void
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mips_send_packet PARAMS ((const char *s, int get_ack));
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static int mips_receive_packet PARAMS ((char *buff, int throw_error,
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int timeout));
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static int
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mips_request PARAMS ((char cmd, unsigned int addr, unsigned int data,
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int *perr, int timeout));
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static void
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mips_initialize PARAMS ((void));
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static void
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mips_open PARAMS ((char *name, int from_tty));
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static void
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mips_close PARAMS ((int quitting));
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static void
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mips_detach PARAMS ((char *args, int from_tty));
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static void mips_resume PARAMS ((int pid, int step,
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enum target_signal siggnal));
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static int
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mips_wait PARAMS ((int pid, struct target_waitstatus *status));
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static int
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mips_map_regno PARAMS ((int regno));
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static void
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mips_fetch_registers PARAMS ((int regno));
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static void
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mips_prepare_to_store PARAMS ((void));
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static void
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mips_store_registers PARAMS ((int regno));
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static int
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mips_fetch_word PARAMS ((CORE_ADDR addr));
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static int
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mips_store_word PARAMS ((CORE_ADDR addr, int value, char *old_contents));
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static int
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mips_xfer_memory PARAMS ((CORE_ADDR memaddr, char *myaddr, int len,
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int write, struct target_ops *ignore));
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static void
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mips_files_info PARAMS ((struct target_ops *ignore));
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static void
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mips_load PARAMS ((char *args, int from_tty));
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static void
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mips_create_inferior PARAMS ((char *execfile, char *args, char **env));
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static void
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mips_mourn_inferior PARAMS ((void));
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/* A forward declaration. */
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extern struct target_ops mips_ops;
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/* The MIPS remote debugging interface is built on top of a simple
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packet protocol. Each packet is organized as follows:
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SYN The first character is always a SYN (ASCII 026, or ^V). SYN
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may not appear anywhere else in the packet. Any time a SYN is
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seen, a new packet should be assumed to have begun.
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TYPE_LEN
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This byte contains the upper five bits of the logical length
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of the data section, plus a single bit indicating whether this
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is a data packet or an acknowledgement. The documentation
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indicates that this bit is 1 for a data packet, but the actual
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board uses 1 for an acknowledgement. The value of the byte is
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0x40 + (ack ? 0x20 : 0) + (len >> 6)
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(we always have 0 <= len < 1024). Acknowledgement packets do
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not carry data, and must have a data length of 0.
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LEN1 This byte contains the lower six bits of the logical length of
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the data section. The value is
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0x40 + (len & 0x3f)
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SEQ This byte contains the six bit sequence number of the packet.
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The value is
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0x40 + seq
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An acknowlegment packet contains the sequence number of the
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packet being acknowledged plus 1 module 64. Data packets are
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transmitted in sequence. There may only be one outstanding
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unacknowledged data packet at a time. The sequence numbers
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are independent in each direction. If an acknowledgement for
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the previous packet is received (i.e., an acknowledgement with
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the sequence number of the packet just sent) the packet just
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sent should be retransmitted. If no acknowledgement is
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received within a timeout period, the packet should be
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retransmitted. This has an unfortunate failure condition on a
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high-latency line, as a delayed acknowledgement may lead to an
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endless series of duplicate packets.
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DATA The actual data bytes follow. The following characters are
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escaped inline with DLE (ASCII 020, or ^P):
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SYN (026) DLE S
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DLE (020) DLE D
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^C (003) DLE C
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^S (023) DLE s
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^Q (021) DLE q
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The additional DLE characters are not counted in the logical
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length stored in the TYPE_LEN and LEN1 bytes.
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CSUM1
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CSUM2
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CSUM3
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These bytes contain an 18 bit checksum of the complete
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contents of the packet excluding the SEQ byte and the
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CSUM[123] bytes. The checksum is simply the twos complement
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addition of all the bytes treated as unsigned characters. The
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values of the checksum bytes are:
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CSUM1: 0x40 + ((cksum >> 12) & 0x3f)
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CSUM2: 0x40 + ((cksum >> 6) & 0x3f)
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CSUM3: 0x40 + (cksum & 0x3f)
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It happens that the MIPS remote debugging protocol always
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communicates with ASCII strings. Because of this, this
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implementation doesn't bother to handle the DLE quoting mechanism,
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since it will never be required. */
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/* The SYN character which starts each packet. */
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#define SYN '\026'
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/* The 0x40 used to offset each packet (this value ensures that all of
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the header and trailer bytes, other than SYN, are printable ASCII
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characters). */
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#define HDR_OFFSET 0x40
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/* The indices of the bytes in the packet header. */
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#define HDR_INDX_SYN 0
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#define HDR_INDX_TYPE_LEN 1
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#define HDR_INDX_LEN1 2
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#define HDR_INDX_SEQ 3
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#define HDR_LENGTH 4
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/* The data/ack bit in the TYPE_LEN header byte. */
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#define TYPE_LEN_DA_BIT 0x20
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#define TYPE_LEN_DATA 0
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#define TYPE_LEN_ACK TYPE_LEN_DA_BIT
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/* How to compute the header bytes. */
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#define HDR_SET_SYN(data, len, seq) (SYN)
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#define HDR_SET_TYPE_LEN(data, len, seq) \
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(HDR_OFFSET \
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+ ((data) ? TYPE_LEN_DATA : TYPE_LEN_ACK) \
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+ (((len) >> 6) & 0x1f))
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#define HDR_SET_LEN1(data, len, seq) (HDR_OFFSET + ((len) & 0x3f))
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#define HDR_SET_SEQ(data, len, seq) (HDR_OFFSET + (seq))
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/* Check that a header byte is reasonable. */
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#define HDR_CHECK(ch) (((ch) & HDR_OFFSET) == HDR_OFFSET)
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/* Get data from the header. These macros evaluate their argument
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multiple times. */
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#define HDR_IS_DATA(hdr) \
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(((hdr)[HDR_INDX_TYPE_LEN] & TYPE_LEN_DA_BIT) == TYPE_LEN_DATA)
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#define HDR_GET_LEN(hdr) \
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((((hdr)[HDR_INDX_TYPE_LEN] & 0x1f) << 6) + (((hdr)[HDR_INDX_LEN1] & 0x3f)))
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#define HDR_GET_SEQ(hdr) ((hdr)[HDR_INDX_SEQ] & 0x3f)
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/* The maximum data length. */
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#define DATA_MAXLEN 1023
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/* The trailer offset. */
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#define TRLR_OFFSET HDR_OFFSET
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/* The indices of the bytes in the packet trailer. */
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#define TRLR_INDX_CSUM1 0
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#define TRLR_INDX_CSUM2 1
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#define TRLR_INDX_CSUM3 2
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#define TRLR_LENGTH 3
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/* How to compute the trailer bytes. */
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#define TRLR_SET_CSUM1(cksum) (TRLR_OFFSET + (((cksum) >> 12) & 0x3f))
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#define TRLR_SET_CSUM2(cksum) (TRLR_OFFSET + (((cksum) >> 6) & 0x3f))
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#define TRLR_SET_CSUM3(cksum) (TRLR_OFFSET + (((cksum) ) & 0x3f))
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/* Check that a trailer byte is reasonable. */
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#define TRLR_CHECK(ch) (((ch) & TRLR_OFFSET) == TRLR_OFFSET)
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/* Get data from the trailer. This evaluates its argument multiple
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times. */
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#define TRLR_GET_CKSUM(trlr) \
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((((trlr)[TRLR_INDX_CSUM1] & 0x3f) << 12) \
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+ (((trlr)[TRLR_INDX_CSUM2] & 0x3f) << 6) \
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+ ((trlr)[TRLR_INDX_CSUM3] & 0x3f))
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/* The sequence number modulos. */
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#define SEQ_MODULOS (64)
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/* Set to 1 if the target is open. */
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static int mips_is_open;
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/* Set to 1 while the connection is being initialized. */
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static int mips_initializing;
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/* The next sequence number to send. */
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static int mips_send_seq;
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/* The next sequence number we expect to receive. */
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static int mips_receive_seq;
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/* The time to wait before retransmitting a packet, in seconds. */
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static int mips_retransmit_wait = 3;
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/* The number of times to try retransmitting a packet before giving up. */
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static int mips_send_retries = 10;
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/* The number of garbage characters to accept when looking for an
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SYN for the next packet. */
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static int mips_syn_garbage = 1050;
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/* The time to wait for a packet, in seconds. */
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static int mips_receive_wait = 5;
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/* Set if we have sent a packet to the board but have not yet received
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a reply. */
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static int mips_need_reply = 0;
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/* Handle used to access serial I/O stream. */
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static serial_t mips_desc;
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/* Handle low-level error that we can't recover from. Note that just
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error()ing out from target_wait or some such low-level place will cause
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all hell to break loose--the rest of GDB will tend to get left in an
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inconsistent state. */
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static void NORETURN
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mips_error (va_alist)
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va_dcl
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{
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va_list args;
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char *string;
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va_start (args);
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target_terminal_ours ();
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wrap_here(""); /* Force out any buffered output */
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gdb_flush (gdb_stdout);
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if (error_pre_print)
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fprintf_filtered (gdb_stderr, error_pre_print);
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string = va_arg (args, char *);
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vfprintf_filtered (gdb_stderr, string, args);
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fprintf_filtered (gdb_stderr, "\n");
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va_end (args);
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/* Clean up in such a way that mips_close won't try to talk to the
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board (it almost surely won't work since we weren't able to talk to
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it). */
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mips_is_open = 0;
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SERIAL_CLOSE (mips_desc);
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printf_unfiltered ("Ending remote MIPS debugging.\n");
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target_mourn_inferior ();
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return_to_top_level (RETURN_ERROR);
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}
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/* Read a character from the remote, aborting on error. Returns
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SERIAL_TIMEOUT on timeout (since that's what SERIAL_READCHAR
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returns). FIXME: If we see the string "<IDT>" from the board, then
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we are debugging on the main console port, and we have somehow
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dropped out of remote debugging mode. In this case, we
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automatically go back in to remote debugging mode. This is a hack,
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put in because I can't find any way for a program running on the
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remote board to terminate without also ending remote debugging
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mode. I assume users won't have any trouble with this; for one
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thing, the IDT documentation generally assumes that the remote
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debugging port is not the console port. This is, however, very
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convenient for DejaGnu when you only have one connected serial
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port. */
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static int
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mips_readchar (timeout)
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int timeout;
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{
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int ch;
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static int state = 0;
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static char nextstate[5] = { '<', 'I', 'D', 'T', '>' };
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ch = SERIAL_READCHAR (mips_desc, timeout);
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if (ch == SERIAL_EOF)
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mips_error ("End of file from remote");
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if (ch == SERIAL_ERROR)
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mips_error ("Error reading from remote: %s", safe_strerror (errno));
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if (sr_get_debug () > 1)
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{
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/* Don't use _filtered; we can't deal with a QUIT out of
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target_wait, and I think this might be called from there. */
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if (ch != SERIAL_TIMEOUT)
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printf_unfiltered ("Read '%c' %d 0x%x\n", ch, ch, ch);
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else
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printf_unfiltered ("Timed out in read\n");
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}
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/* If we have seen <IDT> and we either time out, or we see a @
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(which was echoed from a packet we sent), reset the board as
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described above. The first character in a packet after the SYN
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(which is not echoed) is always an @ unless the packet is more
|
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than 64 characters long, which ours never are. */
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if ((ch == SERIAL_TIMEOUT || ch == '@')
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&& state == 5
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&& ! mips_initializing)
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{
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if (sr_get_debug () > 0)
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/* Don't use _filtered; we can't deal with a QUIT out of
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target_wait, and I think this might be called from there. */
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printf_unfiltered ("Reinitializing MIPS debugging mode\n");
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SERIAL_WRITE (mips_desc, "\rdb tty0\r", sizeof "\rdb tty0\r" - 1);
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sleep (1);
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mips_need_reply = 0;
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mips_initialize ();
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||
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state = 0;
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||
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mips_error ("Remote board reset");
|
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}
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if (ch == nextstate[state])
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++state;
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else
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state = 0;
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return ch;
|
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}
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/* Get a packet header, putting the data in the supplied buffer.
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PGARBAGE is a pointer to the number of garbage characters received
|
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so far. CH is the last character received. Returns 0 for success,
|
||
or -1 for timeout. */
|
||
|
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static int
|
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mips_receive_header (hdr, pgarbage, ch, timeout)
|
||
unsigned char *hdr;
|
||
int *pgarbage;
|
||
int ch;
|
||
int timeout;
|
||
{
|
||
int i;
|
||
|
||
while (1)
|
||
{
|
||
/* Wait for a SYN. mips_syn_garbage is intended to prevent
|
||
sitting here indefinitely if the board sends us one garbage
|
||
character per second. ch may already have a value from the
|
||
last time through the loop. */
|
||
while (ch != SYN)
|
||
{
|
||
ch = mips_readchar (timeout);
|
||
if (ch == SERIAL_TIMEOUT)
|
||
return -1;
|
||
if (ch != SYN)
|
||
{
|
||
/* Printing the character here lets the user of gdb see
|
||
what the program is outputting, if the debugging is
|
||
being done on the console port. Don't use _filtered;
|
||
we can't deal with a QUIT out of target_wait. */
|
||
if (! mips_initializing || sr_get_debug () > 0)
|
||
{
|
||
putchar_unfiltered (ch);
|
||
gdb_flush (gdb_stdout);
|
||
}
|
||
|
||
++*pgarbage;
|
||
if (*pgarbage > mips_syn_garbage)
|
||
mips_error ("Remote debugging protocol failure");
|
||
}
|
||
}
|
||
|
||
/* Get the packet header following the SYN. */
|
||
for (i = 1; i < HDR_LENGTH; i++)
|
||
{
|
||
ch = mips_readchar (timeout);
|
||
if (ch == SERIAL_TIMEOUT)
|
||
return -1;
|
||
|
||
/* Make sure this is a header byte. */
|
||
if (ch == SYN || ! HDR_CHECK (ch))
|
||
break;
|
||
|
||
hdr[i] = ch;
|
||
}
|
||
|
||
/* If we got the complete header, we can return. Otherwise we
|
||
loop around and keep looking for SYN. */
|
||
if (i >= HDR_LENGTH)
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
/* Get a packet header, putting the data in the supplied buffer.
|
||
PGARBAGE is a pointer to the number of garbage characters received
|
||
so far. The last character read is returned in *PCH. Returns 0
|
||
for success, -1 for timeout, -2 for error. */
|
||
|
||
static int
|
||
mips_receive_trailer (trlr, pgarbage, pch, timeout)
|
||
unsigned char *trlr;
|
||
int *pgarbage;
|
||
int *pch;
|
||
int timeout;
|
||
{
|
||
int i;
|
||
int ch;
|
||
|
||
for (i = 0; i < TRLR_LENGTH; i++)
|
||
{
|
||
ch = mips_readchar (timeout);
|
||
*pch = ch;
|
||
if (ch == SERIAL_TIMEOUT)
|
||
return -1;
|
||
if (! TRLR_CHECK (ch))
|
||
return -2;
|
||
trlr[i] = ch;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* Get the checksum of a packet. HDR points to the packet header.
|
||
DATA points to the packet data. LEN is the length of DATA. */
|
||
|
||
static int
|
||
mips_cksum (hdr, data, len)
|
||
const unsigned char *hdr;
|
||
const unsigned char *data;
|
||
int len;
|
||
{
|
||
register const unsigned char *p;
|
||
register int c;
|
||
register int cksum;
|
||
|
||
cksum = 0;
|
||
|
||
/* The initial SYN is not included in the checksum. */
|
||
c = HDR_LENGTH - 1;
|
||
p = hdr + 1;
|
||
while (c-- != 0)
|
||
cksum += *p++;
|
||
|
||
c = len;
|
||
p = data;
|
||
while (c-- != 0)
|
||
cksum += *p++;
|
||
|
||
return cksum;
|
||
}
|
||
|
||
/* Send a packet containing the given ASCII string. */
|
||
|
||
static void
|
||
mips_send_packet (s, get_ack)
|
||
const char *s;
|
||
int get_ack;
|
||
{
|
||
unsigned int len;
|
||
unsigned char *packet;
|
||
register int cksum;
|
||
int try;
|
||
|
||
len = strlen (s);
|
||
if (len > DATA_MAXLEN)
|
||
mips_error ("MIPS protocol data packet too long: %s", s);
|
||
|
||
packet = (unsigned char *) alloca (HDR_LENGTH + len + TRLR_LENGTH + 1);
|
||
|
||
packet[HDR_INDX_SYN] = HDR_SET_SYN (1, len, mips_send_seq);
|
||
packet[HDR_INDX_TYPE_LEN] = HDR_SET_TYPE_LEN (1, len, mips_send_seq);
|
||
packet[HDR_INDX_LEN1] = HDR_SET_LEN1 (1, len, mips_send_seq);
|
||
packet[HDR_INDX_SEQ] = HDR_SET_SEQ (1, len, mips_send_seq);
|
||
|
||
memcpy (packet + HDR_LENGTH, s, len);
|
||
|
||
cksum = mips_cksum (packet, packet + HDR_LENGTH, len);
|
||
packet[HDR_LENGTH + len + TRLR_INDX_CSUM1] = TRLR_SET_CSUM1 (cksum);
|
||
packet[HDR_LENGTH + len + TRLR_INDX_CSUM2] = TRLR_SET_CSUM2 (cksum);
|
||
packet[HDR_LENGTH + len + TRLR_INDX_CSUM3] = TRLR_SET_CSUM3 (cksum);
|
||
|
||
/* Increment the sequence number. This will set mips_send_seq to
|
||
the sequence number we expect in the acknowledgement. */
|
||
mips_send_seq = (mips_send_seq + 1) % SEQ_MODULOS;
|
||
|
||
if (! get_ack)
|
||
return;
|
||
|
||
/* We can only have one outstanding data packet, so we just wait for
|
||
the acknowledgement here. Keep retransmitting the packet until
|
||
we get one, or until we've tried too many times. */
|
||
for (try = 0; try < mips_send_retries; try++)
|
||
{
|
||
int garbage;
|
||
int ch;
|
||
|
||
if (sr_get_debug () > 0)
|
||
{
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
packet[HDR_LENGTH + len + TRLR_LENGTH] = '\0';
|
||
printf_unfiltered ("Writing \"%s\"\n", packet + 1);
|
||
}
|
||
|
||
if (SERIAL_WRITE (mips_desc, packet,
|
||
HDR_LENGTH + len + TRLR_LENGTH) != 0)
|
||
mips_error ("write to target failed: %s", safe_strerror (errno));
|
||
|
||
garbage = 0;
|
||
ch = 0;
|
||
while (1)
|
||
{
|
||
unsigned char hdr[HDR_LENGTH + 1];
|
||
unsigned char trlr[TRLR_LENGTH + 1];
|
||
int err;
|
||
int seq;
|
||
|
||
/* Get the packet header. If we time out, resend the data
|
||
packet. */
|
||
err = mips_receive_header (hdr, &garbage, ch, mips_retransmit_wait);
|
||
if (err != 0)
|
||
break;
|
||
|
||
ch = 0;
|
||
|
||
/* If we get a data packet, assume it is a duplicate and
|
||
ignore it. FIXME: If the acknowledgement is lost, this
|
||
data packet may be the packet the remote sends after the
|
||
acknowledgement. */
|
||
if (HDR_IS_DATA (hdr))
|
||
continue;
|
||
|
||
/* If the length is not 0, this is a garbled packet. */
|
||
if (HDR_GET_LEN (hdr) != 0)
|
||
continue;
|
||
|
||
/* Get the packet trailer. */
|
||
err = mips_receive_trailer (trlr, &garbage, &ch,
|
||
mips_retransmit_wait);
|
||
|
||
/* If we timed out, resend the data packet. */
|
||
if (err == -1)
|
||
break;
|
||
|
||
/* If we got a bad character, reread the header. */
|
||
if (err != 0)
|
||
continue;
|
||
|
||
/* If the checksum does not match the trailer checksum, this
|
||
is a bad packet; ignore it. */
|
||
if (mips_cksum (hdr, (unsigned char *) NULL, 0)
|
||
!= TRLR_GET_CKSUM (trlr))
|
||
continue;
|
||
|
||
if (sr_get_debug () > 0)
|
||
{
|
||
hdr[HDR_LENGTH] = '\0';
|
||
trlr[TRLR_LENGTH] = '\0';
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
printf_unfiltered ("Got ack %d \"%s%s\"\n",
|
||
HDR_GET_SEQ (hdr), hdr + 1, trlr);
|
||
}
|
||
|
||
/* If this ack is for the current packet, we're done. */
|
||
seq = HDR_GET_SEQ (hdr);
|
||
if (seq == mips_send_seq)
|
||
return;
|
||
|
||
/* If this ack is for the last packet, resend the current
|
||
packet. */
|
||
if ((seq + 1) % SEQ_MODULOS == mips_send_seq)
|
||
break;
|
||
|
||
/* Otherwise this is a bad ack; ignore it. Increment the
|
||
garbage count to ensure that we do not stay in this loop
|
||
forever. */
|
||
++garbage;
|
||
}
|
||
}
|
||
|
||
mips_error ("Remote did not acknowledge packet");
|
||
}
|
||
|
||
/* Receive and acknowledge a packet, returning the data in BUFF (which
|
||
should be DATA_MAXLEN + 1 bytes). The protocol documentation
|
||
implies that only the sender retransmits packets, so this code just
|
||
waits silently for a packet. It returns the length of the received
|
||
packet. If THROW_ERROR is nonzero, call error() on errors. If not,
|
||
don't print an error message and return -1. */
|
||
|
||
static int
|
||
mips_receive_packet (buff, throw_error, timeout)
|
||
char *buff;
|
||
int throw_error;
|
||
int timeout;
|
||
{
|
||
int ch;
|
||
int garbage;
|
||
int len;
|
||
unsigned char ack[HDR_LENGTH + TRLR_LENGTH + 1];
|
||
int cksum;
|
||
|
||
ch = 0;
|
||
garbage = 0;
|
||
while (1)
|
||
{
|
||
unsigned char hdr[HDR_LENGTH];
|
||
unsigned char trlr[TRLR_LENGTH];
|
||
int i;
|
||
int err;
|
||
|
||
if (mips_receive_header (hdr, &garbage, ch, timeout) != 0)
|
||
{
|
||
if (throw_error)
|
||
mips_error ("Timed out waiting for remote packet");
|
||
else
|
||
return -1;
|
||
}
|
||
|
||
ch = 0;
|
||
|
||
/* An acknowledgement is probably a duplicate; ignore it. */
|
||
if (! HDR_IS_DATA (hdr))
|
||
{
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
if (sr_get_debug () > 0)
|
||
printf_unfiltered ("Ignoring unexpected ACK\n");
|
||
continue;
|
||
}
|
||
|
||
/* If this is the wrong sequence number, ignore it. */
|
||
if (HDR_GET_SEQ (hdr) != mips_receive_seq)
|
||
{
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
if (sr_get_debug () > 0)
|
||
printf_unfiltered ("Ignoring sequence number %d (want %d)\n",
|
||
HDR_GET_SEQ (hdr), mips_receive_seq);
|
||
continue;
|
||
}
|
||
|
||
len = HDR_GET_LEN (hdr);
|
||
|
||
for (i = 0; i < len; i++)
|
||
{
|
||
int rch;
|
||
|
||
rch = mips_readchar (timeout);
|
||
if (rch == SYN)
|
||
{
|
||
ch = SYN;
|
||
break;
|
||
}
|
||
if (rch == SERIAL_TIMEOUT)
|
||
{
|
||
if (throw_error)
|
||
mips_error ("Timed out waiting for remote packet");
|
||
else
|
||
return -1;
|
||
}
|
||
buff[i] = rch;
|
||
}
|
||
|
||
if (i < len)
|
||
{
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
if (sr_get_debug () > 0)
|
||
printf_unfiltered ("Got new SYN after %d chars (wanted %d)\n",
|
||
i, len);
|
||
continue;
|
||
}
|
||
|
||
err = mips_receive_trailer (trlr, &garbage, &ch, timeout);
|
||
if (err == -1)
|
||
{
|
||
if (throw_error)
|
||
mips_error ("Timed out waiting for packet");
|
||
else
|
||
return -1;
|
||
}
|
||
if (err == -2)
|
||
{
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
if (sr_get_debug () > 0)
|
||
printf_unfiltered ("Got SYN when wanted trailer\n");
|
||
continue;
|
||
}
|
||
|
||
if (mips_cksum (hdr, buff, len) == TRLR_GET_CKSUM (trlr))
|
||
break;
|
||
|
||
if (sr_get_debug () > 0)
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
printf_unfiltered ("Bad checksum; data %d, trailer %d\n",
|
||
mips_cksum (hdr, buff, len),
|
||
TRLR_GET_CKSUM (trlr));
|
||
|
||
/* The checksum failed. Send an acknowledgement for the
|
||
previous packet to tell the remote to resend the packet. */
|
||
ack[HDR_INDX_SYN] = HDR_SET_SYN (0, 0, mips_receive_seq);
|
||
ack[HDR_INDX_TYPE_LEN] = HDR_SET_TYPE_LEN (0, 0, mips_receive_seq);
|
||
ack[HDR_INDX_LEN1] = HDR_SET_LEN1 (0, 0, mips_receive_seq);
|
||
ack[HDR_INDX_SEQ] = HDR_SET_SEQ (0, 0, mips_receive_seq);
|
||
|
||
cksum = mips_cksum (ack, (unsigned char *) NULL, 0);
|
||
|
||
ack[HDR_LENGTH + TRLR_INDX_CSUM1] = TRLR_SET_CSUM1 (cksum);
|
||
ack[HDR_LENGTH + TRLR_INDX_CSUM2] = TRLR_SET_CSUM2 (cksum);
|
||
ack[HDR_LENGTH + TRLR_INDX_CSUM3] = TRLR_SET_CSUM3 (cksum);
|
||
|
||
if (sr_get_debug () > 0)
|
||
{
|
||
ack[HDR_LENGTH + TRLR_LENGTH] = '\0';
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
printf_unfiltered ("Writing ack %d \"%s\"\n", mips_receive_seq,
|
||
ack + 1);
|
||
}
|
||
|
||
if (SERIAL_WRITE (mips_desc, ack, HDR_LENGTH + TRLR_LENGTH) != 0)
|
||
{
|
||
if (throw_error)
|
||
mips_error ("write to target failed: %s", safe_strerror (errno));
|
||
else
|
||
return -1;
|
||
}
|
||
}
|
||
|
||
if (sr_get_debug () > 0)
|
||
{
|
||
buff[len] = '\0';
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
printf_unfiltered ("Got packet \"%s\"\n", buff);
|
||
}
|
||
|
||
/* We got the packet. Send an acknowledgement. */
|
||
mips_receive_seq = (mips_receive_seq + 1) % SEQ_MODULOS;
|
||
|
||
ack[HDR_INDX_SYN] = HDR_SET_SYN (0, 0, mips_receive_seq);
|
||
ack[HDR_INDX_TYPE_LEN] = HDR_SET_TYPE_LEN (0, 0, mips_receive_seq);
|
||
ack[HDR_INDX_LEN1] = HDR_SET_LEN1 (0, 0, mips_receive_seq);
|
||
ack[HDR_INDX_SEQ] = HDR_SET_SEQ (0, 0, mips_receive_seq);
|
||
|
||
cksum = mips_cksum (ack, (unsigned char *) NULL, 0);
|
||
|
||
ack[HDR_LENGTH + TRLR_INDX_CSUM1] = TRLR_SET_CSUM1 (cksum);
|
||
ack[HDR_LENGTH + TRLR_INDX_CSUM2] = TRLR_SET_CSUM2 (cksum);
|
||
ack[HDR_LENGTH + TRLR_INDX_CSUM3] = TRLR_SET_CSUM3 (cksum);
|
||
|
||
if (sr_get_debug () > 0)
|
||
{
|
||
ack[HDR_LENGTH + TRLR_LENGTH] = '\0';
|
||
/* Don't use _filtered; we can't deal with a QUIT out of
|
||
target_wait, and I think this might be called from there. */
|
||
printf_unfiltered ("Writing ack %d \"%s\"\n", mips_receive_seq,
|
||
ack + 1);
|
||
}
|
||
|
||
if (SERIAL_WRITE (mips_desc, ack, HDR_LENGTH + TRLR_LENGTH) != 0)
|
||
{
|
||
if (throw_error)
|
||
mips_error ("write to target failed: %s", safe_strerror (errno));
|
||
else
|
||
return -1;
|
||
}
|
||
|
||
return len;
|
||
}
|
||
|
||
/* Optionally send a request to the remote system and optionally wait
|
||
for the reply. This implements the remote debugging protocol,
|
||
which is built on top of the packet protocol defined above. Each
|
||
request has an ADDR argument and a DATA argument. The following
|
||
requests are defined:
|
||
|
||
\0 don't send a request; just wait for a reply
|
||
i read word from instruction space at ADDR
|
||
d read word from data space at ADDR
|
||
I write DATA to instruction space at ADDR
|
||
D write DATA to data space at ADDR
|
||
r read register number ADDR
|
||
R set register number ADDR to value DATA
|
||
c continue execution (if ADDR != 1, set pc to ADDR)
|
||
s single step (if ADDR != 1, set pc to ADDR)
|
||
|
||
The read requests return the value requested. The write requests
|
||
return the previous value in the changed location. The execution
|
||
requests return a UNIX wait value (the approximate signal which
|
||
caused execution to stop is in the upper eight bits).
|
||
|
||
If PERR is not NULL, this function waits for a reply. If an error
|
||
occurs, it sets *PERR to 1 and sets errno according to what the
|
||
target board reports. */
|
||
|
||
static int
|
||
mips_request (cmd, addr, data, perr, timeout)
|
||
char cmd;
|
||
unsigned int addr;
|
||
unsigned int data;
|
||
int *perr;
|
||
int timeout;
|
||
{
|
||
char buff[DATA_MAXLEN + 1];
|
||
int len;
|
||
int rpid;
|
||
char rcmd;
|
||
int rerrflg;
|
||
int rresponse;
|
||
|
||
if (cmd != '\0')
|
||
{
|
||
if (mips_need_reply)
|
||
fatal ("mips_request: Trying to send command before reply");
|
||
sprintf (buff, "0x0 %c 0x%x 0x%x", cmd, addr, data);
|
||
mips_send_packet (buff, 1);
|
||
mips_need_reply = 1;
|
||
}
|
||
|
||
if (perr == (int *) NULL)
|
||
return 0;
|
||
|
||
if (! mips_need_reply)
|
||
fatal ("mips_request: Trying to get reply before command");
|
||
|
||
mips_need_reply = 0;
|
||
|
||
len = mips_receive_packet (buff, 1, timeout);
|
||
buff[len] = '\0';
|
||
|
||
if (sscanf (buff, "0x%x %c 0x%x 0x%x",
|
||
&rpid, &rcmd, &rerrflg, &rresponse) != 4
|
||
|| (cmd != '\0' && rcmd != cmd))
|
||
mips_error ("Bad response from remote board");
|
||
|
||
if (rerrflg != 0)
|
||
{
|
||
*perr = 1;
|
||
|
||
/* FIXME: This will returns MIPS errno numbers, which may or may
|
||
not be the same as errno values used on other systems. If
|
||
they stick to common errno values, they will be the same, but
|
||
if they don't, they must be translated. */
|
||
errno = rresponse;
|
||
|
||
return 0;
|
||
}
|
||
|
||
*perr = 0;
|
||
return rresponse;
|
||
}
|
||
|
||
static void
|
||
mips_initialize_cleanups (arg)
|
||
PTR arg;
|
||
{
|
||
mips_initializing = 0;
|
||
}
|
||
|
||
/* Initialize a new connection to the MIPS board, and make sure we are
|
||
really connected. */
|
||
|
||
static void
|
||
mips_initialize ()
|
||
{
|
||
char cr;
|
||
char buff[DATA_MAXLEN + 1];
|
||
int err;
|
||
struct cleanup *old_cleanups = make_cleanup (mips_initialize_cleanups, NULL);
|
||
|
||
/* What is this code doing here? I don't see any way it can happen, and
|
||
it might mean mips_initializing didn't get cleared properly.
|
||
So I'll make it a warning. */
|
||
if (mips_initializing)
|
||
{
|
||
warning ("internal error: mips_initialize called twice");
|
||
return;
|
||
}
|
||
|
||
mips_initializing = 1;
|
||
|
||
mips_send_seq = 0;
|
||
mips_receive_seq = 0;
|
||
|
||
/* The board seems to want to send us a packet. I don't know what
|
||
it means. The packet seems to be triggered by a carriage return
|
||
character, although perhaps any character would do. */
|
||
cr = '\r';
|
||
SERIAL_WRITE (mips_desc, &cr, 1);
|
||
|
||
if (mips_receive_packet (buff, 0, 3) < 0)
|
||
{
|
||
char cc;
|
||
|
||
/* We did not receive the packet we expected; try resetting the
|
||
board and trying again. */
|
||
printf_filtered ("Failed to initialize; trying to reset board\n");
|
||
cc = '\003';
|
||
SERIAL_WRITE (mips_desc, &cc, 1);
|
||
sleep (2);
|
||
SERIAL_WRITE (mips_desc, "\rdb tty0\r", sizeof "\rdb tty0\r" - 1);
|
||
sleep (1);
|
||
cr = '\r';
|
||
SERIAL_WRITE (mips_desc, &cr, 1);
|
||
}
|
||
mips_receive_packet (buff, 1, 3);
|
||
|
||
do_cleanups (old_cleanups);
|
||
|
||
/* If this doesn't call error, we have connected; we don't care if
|
||
the request itself succeeds or fails. */
|
||
mips_request ('r', (unsigned int) 0, (unsigned int) 0, &err,
|
||
mips_receive_wait);
|
||
}
|
||
|
||
/* Open a connection to the remote board. */
|
||
|
||
static void
|
||
mips_open (name, from_tty)
|
||
char *name;
|
||
int from_tty;
|
||
{
|
||
if (name == 0)
|
||
error (
|
||
"To open a MIPS remote debugging connection, you need to specify what serial\n\
|
||
device is attached to the target board (e.g., /dev/ttya).");
|
||
|
||
target_preopen (from_tty);
|
||
|
||
if (mips_is_open)
|
||
unpush_target (&mips_ops);
|
||
|
||
mips_desc = SERIAL_OPEN (name);
|
||
if (mips_desc == (serial_t) NULL)
|
||
perror_with_name (name);
|
||
|
||
SERIAL_RAW (mips_desc);
|
||
|
||
mips_is_open = 1;
|
||
|
||
mips_initialize ();
|
||
|
||
if (from_tty)
|
||
printf_unfiltered ("Remote MIPS debugging using %s\n", name);
|
||
push_target (&mips_ops); /* Switch to using remote target now */
|
||
|
||
/* FIXME: Should we call start_remote here? */
|
||
}
|
||
|
||
/* Close a connection to the remote board. */
|
||
|
||
static void
|
||
mips_close (quitting)
|
||
int quitting;
|
||
{
|
||
if (mips_is_open)
|
||
{
|
||
int err;
|
||
|
||
mips_is_open = 0;
|
||
|
||
/* Get the board out of remote debugging mode. */
|
||
mips_request ('x', (unsigned int) 0, (unsigned int) 0, &err,
|
||
mips_receive_wait);
|
||
|
||
SERIAL_CLOSE (mips_desc);
|
||
}
|
||
}
|
||
|
||
/* Detach from the remote board. */
|
||
|
||
static void
|
||
mips_detach (args, from_tty)
|
||
char *args;
|
||
int from_tty;
|
||
{
|
||
if (args)
|
||
error ("Argument given to \"detach\" when remotely debugging.");
|
||
|
||
pop_target ();
|
||
if (from_tty)
|
||
printf_unfiltered ("Ending remote MIPS debugging.\n");
|
||
}
|
||
|
||
/* Tell the target board to resume. This does not wait for a reply
|
||
from the board. */
|
||
|
||
static void
|
||
mips_resume (pid, step, siggnal)
|
||
int pid, step;
|
||
enum target_signal siggnal;
|
||
{
|
||
if (siggnal != TARGET_SIGNAL_0)
|
||
warning
|
||
("Can't send signals to a remote system. Try `handle %s ignore'.",
|
||
target_signal_to_name (siggnal));
|
||
|
||
mips_request (step ? 's' : 'c',
|
||
(unsigned int) 1,
|
||
(unsigned int) 0,
|
||
(int *) NULL,
|
||
mips_receive_wait);
|
||
}
|
||
|
||
/* Return the signal corresponding to SIG, where SIG is the number which
|
||
the MIPS protocol uses for the signal. */
|
||
enum target_signal
|
||
mips_signal_from_protocol (sig)
|
||
int sig;
|
||
{
|
||
/* We allow a few more signals than the IDT board actually returns, on
|
||
the theory that there is at least *some* hope that perhaps the numbering
|
||
for these signals is widely agreed upon. */
|
||
if (sig <= 0
|
||
|| sig > 31)
|
||
return TARGET_SIGNAL_UNKNOWN;
|
||
|
||
/* Don't want to use target_signal_from_host because we are converting
|
||
from MIPS signal numbers, not host ones. Our internal numbers
|
||
match the MIPS numbers for the signals the board can return, which
|
||
are: SIGINT, SIGSEGV, SIGBUS, SIGILL, SIGFPE, SIGTRAP. */
|
||
return (enum target_signal) sig;
|
||
}
|
||
|
||
/* Wait until the remote stops, and return a wait status. */
|
||
|
||
static int
|
||
mips_wait (pid, status)
|
||
int pid;
|
||
struct target_waitstatus *status;
|
||
{
|
||
int rstatus;
|
||
int err;
|
||
|
||
/* If we have not sent a single step or continue command, then the
|
||
board is waiting for us to do something. Return a status
|
||
indicating that it is stopped. */
|
||
if (! mips_need_reply)
|
||
{
|
||
status->kind = TARGET_WAITKIND_STOPPED;
|
||
status->value.sig = TARGET_SIGNAL_TRAP;
|
||
return 0;
|
||
}
|
||
|
||
/* No timeout; we sit here as long as the program continues to execute. */
|
||
rstatus = mips_request ('\0', (unsigned int) 0, (unsigned int) 0, &err, -1);
|
||
if (err)
|
||
mips_error ("Remote failure: %s", safe_strerror (errno));
|
||
|
||
/* Translate a MIPS waitstatus. We use constants here rather than WTERMSIG
|
||
and so on, because the constants we want here are determined by the
|
||
MIPS protocol and have nothing to do with what host we are running on. */
|
||
if ((rstatus & 0377) == 0)
|
||
{
|
||
status->kind = TARGET_WAITKIND_EXITED;
|
||
status->value.integer = (((rstatus) >> 8) & 0377);
|
||
}
|
||
else if ((rstatus & 0377) == 0177)
|
||
{
|
||
status->kind = TARGET_WAITKIND_STOPPED;
|
||
status->value.sig = mips_signal_from_protocol (((rstatus) >> 8) & 0377);
|
||
}
|
||
else
|
||
{
|
||
status->kind = TARGET_WAITKIND_SIGNALLED;
|
||
status->value.sig = mips_signal_from_protocol (rstatus & 0177);
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* We have to map between the register numbers used by gdb and the
|
||
register numbers used by the debugging protocol. This function
|
||
assumes that we are using tm-mips.h. */
|
||
|
||
#define REGNO_OFFSET 96
|
||
|
||
static int
|
||
mips_map_regno (regno)
|
||
int regno;
|
||
{
|
||
if (regno < 32)
|
||
return regno;
|
||
if (regno >= FP0_REGNUM && regno < FP0_REGNUM + 32)
|
||
return regno - FP0_REGNUM + 32;
|
||
switch (regno)
|
||
{
|
||
case PC_REGNUM:
|
||
return REGNO_OFFSET + 0;
|
||
case CAUSE_REGNUM:
|
||
return REGNO_OFFSET + 1;
|
||
case HI_REGNUM:
|
||
return REGNO_OFFSET + 2;
|
||
case LO_REGNUM:
|
||
return REGNO_OFFSET + 3;
|
||
case FCRCS_REGNUM:
|
||
return REGNO_OFFSET + 4;
|
||
case FCRIR_REGNUM:
|
||
return REGNO_OFFSET + 5;
|
||
default:
|
||
/* FIXME: Is there a way to get the status register? */
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
/* Fetch the remote registers. */
|
||
|
||
static void
|
||
mips_fetch_registers (regno)
|
||
int regno;
|
||
{
|
||
unsigned LONGEST val;
|
||
int err;
|
||
|
||
if (regno == -1)
|
||
{
|
||
for (regno = 0; regno < NUM_REGS; regno++)
|
||
mips_fetch_registers (regno);
|
||
return;
|
||
}
|
||
|
||
if (regno == FP_REGNUM || regno == ZERO_REGNUM)
|
||
/* FP_REGNUM on the mips is a hack which is just supposed to read
|
||
zero (see also mips-nat.c). */
|
||
val = 0;
|
||
else
|
||
{
|
||
val = mips_request ('r', (unsigned int) mips_map_regno (regno),
|
||
(unsigned int) 0, &err, mips_receive_wait);
|
||
if (err)
|
||
mips_error ("Can't read register %d: %s", regno,
|
||
safe_strerror (errno));
|
||
}
|
||
|
||
{
|
||
char buf[MAX_REGISTER_RAW_SIZE];
|
||
|
||
/* We got the number the register holds, but gdb expects to see a
|
||
value in the target byte ordering. */
|
||
store_unsigned_integer (buf, REGISTER_RAW_SIZE (regno), val);
|
||
supply_register (regno, buf);
|
||
}
|
||
}
|
||
|
||
/* Prepare to store registers. The MIPS protocol can store individual
|
||
registers, so this function doesn't have to do anything. */
|
||
|
||
static void
|
||
mips_prepare_to_store ()
|
||
{
|
||
}
|
||
|
||
/* Store remote register(s). */
|
||
|
||
static void
|
||
mips_store_registers (regno)
|
||
int regno;
|
||
{
|
||
int err;
|
||
|
||
if (regno == -1)
|
||
{
|
||
for (regno = 0; regno < NUM_REGS; regno++)
|
||
mips_store_registers (regno);
|
||
return;
|
||
}
|
||
|
||
mips_request ('R', (unsigned int) mips_map_regno (regno),
|
||
(unsigned int) read_register (regno),
|
||
&err, mips_receive_wait);
|
||
if (err)
|
||
mips_error ("Can't write register %d: %s", regno, safe_strerror (errno));
|
||
}
|
||
|
||
/* Fetch a word from the target board. */
|
||
|
||
static int
|
||
mips_fetch_word (addr)
|
||
CORE_ADDR addr;
|
||
{
|
||
int val;
|
||
int err;
|
||
|
||
val = mips_request ('d', (unsigned int) addr, (unsigned int) 0, &err,
|
||
mips_receive_wait);
|
||
if (err)
|
||
{
|
||
/* Data space failed; try instruction space. */
|
||
val = mips_request ('i', (unsigned int) addr, (unsigned int) 0, &err,
|
||
mips_receive_wait);
|
||
if (err)
|
||
mips_error ("Can't read address 0x%x: %s", addr, safe_strerror (errno));
|
||
}
|
||
return val;
|
||
}
|
||
|
||
/* Store a word to the target board. Returns errno code or zero for
|
||
success. If OLD_CONTENTS is non-NULL, put the old contents of that
|
||
memory location there. */
|
||
|
||
static int
|
||
mips_store_word (addr, val, old_contents)
|
||
CORE_ADDR addr;
|
||
int val;
|
||
char *old_contents;
|
||
{
|
||
int err;
|
||
unsigned int oldcontents;
|
||
|
||
oldcontents = mips_request ('D', (unsigned int) addr, (unsigned int) val,
|
||
&err,
|
||
mips_receive_wait);
|
||
if (err)
|
||
{
|
||
/* Data space failed; try instruction space. */
|
||
oldcontents = mips_request ('I', (unsigned int) addr,
|
||
(unsigned int) val, &err,
|
||
mips_receive_wait);
|
||
if (err)
|
||
return errno;
|
||
}
|
||
if (old_contents != NULL)
|
||
store_unsigned_integer (old_contents, 4, oldcontents);
|
||
return 0;
|
||
}
|
||
|
||
/* Read or write LEN bytes from inferior memory at MEMADDR,
|
||
transferring to or from debugger address MYADDR. Write to inferior
|
||
if SHOULD_WRITE is nonzero. Returns length of data written or
|
||
read; 0 for error. Note that protocol gives us the correct value
|
||
for a longword, since it transfers values in ASCII. We want the
|
||
byte values, so we have to swap the longword values. */
|
||
|
||
static int
|
||
mips_xfer_memory (memaddr, myaddr, len, write, ignore)
|
||
CORE_ADDR memaddr;
|
||
char *myaddr;
|
||
int len;
|
||
int write;
|
||
struct target_ops *ignore;
|
||
{
|
||
register int i;
|
||
/* Round starting address down to longword boundary. */
|
||
register CORE_ADDR addr = memaddr &~ 3;
|
||
/* Round ending address up; get number of longwords that makes. */
|
||
register int count = (((memaddr + len) - addr) + 3) / 4;
|
||
/* Allocate buffer of that many longwords. */
|
||
register char *buffer = alloca (count * 4);
|
||
|
||
int status;
|
||
|
||
if (write)
|
||
{
|
||
/* Fill start and end extra bytes of buffer with existing data. */
|
||
if (addr != memaddr || len < 4)
|
||
{
|
||
/* Need part of initial word -- fetch it. */
|
||
store_unsigned_integer (&buffer[0], 4, mips_fetch_word (addr));
|
||
}
|
||
|
||
if (count > 1)
|
||
{
|
||
/* Need part of last word -- fetch it. FIXME: we do this even
|
||
if we don't need it. */
|
||
store_unsigned_integer (&buffer[(count - 1) * 4], 4,
|
||
mips_fetch_word (addr + (count - 1) * 4));
|
||
}
|
||
|
||
/* Copy data to be written over corresponding part of buffer */
|
||
|
||
memcpy ((char *) buffer + (memaddr & 3), myaddr, len);
|
||
|
||
/* Write the entire buffer. */
|
||
|
||
for (i = 0; i < count; i++, addr += 4)
|
||
{
|
||
status = mips_store_word (addr,
|
||
extract_unsigned_integer (&buffer[i*4], 4),
|
||
NULL);
|
||
if (status)
|
||
{
|
||
errno = status;
|
||
return 0;
|
||
}
|
||
/* FIXME: Do we want a QUIT here? */
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* Read all the longwords */
|
||
for (i = 0; i < count; i++, addr += 4)
|
||
{
|
||
store_unsigned_integer (&buffer[i*4], 4, mips_fetch_word (addr));
|
||
QUIT;
|
||
}
|
||
|
||
/* Copy appropriate bytes out of the buffer. */
|
||
memcpy (myaddr, buffer + (memaddr & 3), len);
|
||
}
|
||
return len;
|
||
}
|
||
|
||
/* Print info on this target. */
|
||
|
||
static void
|
||
mips_files_info (ignore)
|
||
struct target_ops *ignore;
|
||
{
|
||
printf_unfiltered ("Debugging a MIPS board over a serial line.\n");
|
||
}
|
||
|
||
/* Kill the process running on the board. This will actually only
|
||
work if we are doing remote debugging over the console input. I
|
||
think that if IDT/sim had the remote debug interrupt enabled on the
|
||
right port, we could interrupt the process with a break signal. */
|
||
|
||
static void
|
||
mips_kill ()
|
||
{
|
||
#if 0
|
||
if (mips_is_open)
|
||
{
|
||
char cc;
|
||
|
||
/* Send a ^C. */
|
||
cc = '\003';
|
||
SERIAL_WRITE (mips_desc, &cc, 1);
|
||
sleep (1);
|
||
target_mourn_inferior ();
|
||
}
|
||
#endif
|
||
}
|
||
|
||
/* Start running on the target board. */
|
||
|
||
static void
|
||
mips_create_inferior (execfile, args, env)
|
||
char *execfile;
|
||
char *args;
|
||
char **env;
|
||
{
|
||
CORE_ADDR entry_pt;
|
||
|
||
if (args && *args)
|
||
{
|
||
warning ("\
|
||
Can't pass arguments to remote MIPS board; arguments ignored.");
|
||
/* And don't try to use them on the next "run" command. */
|
||
execute_command ("set args", 0);
|
||
}
|
||
|
||
if (execfile == 0 || exec_bfd == 0)
|
||
error ("No executable file specified");
|
||
|
||
entry_pt = (CORE_ADDR) bfd_get_start_address (exec_bfd);
|
||
|
||
init_wait_for_inferior ();
|
||
|
||
/* FIXME: Should we set inferior_pid here? */
|
||
|
||
proceed (entry_pt, TARGET_SIGNAL_DEFAULT, 0);
|
||
}
|
||
|
||
/* Clean up after a process. Actually nothing to do. */
|
||
|
||
static void
|
||
mips_mourn_inferior ()
|
||
{
|
||
unpush_target (&mips_ops);
|
||
generic_mourn_inferior ();
|
||
}
|
||
|
||
/* We can write a breakpoint and read the shadow contents in one
|
||
operation. */
|
||
|
||
/* The IDT board uses an unusual breakpoint value, and sometimes gets
|
||
confused when it sees the usual MIPS breakpoint instruction. */
|
||
|
||
#if TARGET_BYTE_ORDER == BIG_ENDIAN
|
||
static unsigned char break_insn[] = {0, 0, 0x0a, 0x0d};
|
||
#else
|
||
static unsigned char break_insn[] = {0x0d, 0x0a, 0, 0};
|
||
#endif
|
||
|
||
/* Insert a breakpoint on targets that don't have any better breakpoint
|
||
support. We read the contents of the target location and stash it,
|
||
then overwrite it with a breakpoint instruction. ADDR is the target
|
||
location in the target machine. CONTENTS_CACHE is a pointer to
|
||
memory allocated for saving the target contents. It is guaranteed
|
||
by the caller to be long enough to save sizeof BREAKPOINT bytes (this
|
||
is accomplished via BREAKPOINT_MAX). */
|
||
|
||
static int
|
||
mips_insert_breakpoint (addr, contents_cache)
|
||
CORE_ADDR addr;
|
||
char *contents_cache;
|
||
{
|
||
int status;
|
||
|
||
return
|
||
mips_store_word (addr,
|
||
extract_unsigned_integer (break_insn, sizeof break_insn),
|
||
contents_cache);
|
||
}
|
||
|
||
static int
|
||
mips_remove_breakpoint (addr, contents_cache)
|
||
CORE_ADDR addr;
|
||
char *contents_cache;
|
||
{
|
||
return target_write_memory (addr, contents_cache, sizeof break_insn);
|
||
}
|
||
|
||
/* The target vector. */
|
||
|
||
struct target_ops mips_ops =
|
||
{
|
||
"mips", /* to_shortname */
|
||
"Remote MIPS debugging over serial line", /* to_longname */
|
||
"\
|
||
Debug a board using the MIPS remote debugging protocol over a serial line.\n\
|
||
The argument is the device it is connected to or, if it contains a colon,\n\
|
||
HOST:PORT to access a board over a network", /* to_doc */
|
||
mips_open, /* to_open */
|
||
mips_close, /* to_close */
|
||
NULL, /* to_attach */
|
||
mips_detach, /* to_detach */
|
||
mips_resume, /* to_resume */
|
||
mips_wait, /* to_wait */
|
||
mips_fetch_registers, /* to_fetch_registers */
|
||
mips_store_registers, /* to_store_registers */
|
||
mips_prepare_to_store, /* to_prepare_to_store */
|
||
mips_xfer_memory, /* to_xfer_memory */
|
||
mips_files_info, /* to_files_info */
|
||
mips_insert_breakpoint, /* to_insert_breakpoint */
|
||
mips_remove_breakpoint, /* to_remove_breakpoint */
|
||
NULL, /* to_terminal_init */
|
||
NULL, /* to_terminal_inferior */
|
||
NULL, /* to_terminal_ours_for_output */
|
||
NULL, /* to_terminal_ours */
|
||
NULL, /* to_terminal_info */
|
||
mips_kill, /* to_kill */
|
||
generic_load, /* to_load */
|
||
NULL, /* to_lookup_symbol */
|
||
mips_create_inferior, /* to_create_inferior */
|
||
mips_mourn_inferior, /* to_mourn_inferior */
|
||
NULL, /* to_can_run */
|
||
NULL, /* to_notice_signals */
|
||
process_stratum, /* to_stratum */
|
||
NULL, /* to_next */
|
||
1, /* to_has_all_memory */
|
||
1, /* to_has_memory */
|
||
1, /* to_has_stack */
|
||
1, /* to_has_registers */
|
||
1, /* to_has_execution */
|
||
NULL, /* sections */
|
||
NULL, /* sections_end */
|
||
OPS_MAGIC /* to_magic */
|
||
};
|
||
|
||
void
|
||
_initialize_remote_mips ()
|
||
{
|
||
add_target (&mips_ops);
|
||
|
||
add_show_from_set (
|
||
add_set_cmd ("timeout", no_class, var_zinteger,
|
||
(char *) &mips_receive_wait,
|
||
"Set timeout in seconds for remote MIPS serial I/O.",
|
||
&setlist),
|
||
&showlist);
|
||
|
||
add_show_from_set (
|
||
add_set_cmd ("retransmit-timeout", no_class, var_zinteger,
|
||
(char *) &mips_retransmit_wait,
|
||
"Set retransmit timeout in seconds for remote MIPS serial I/O.\n\
|
||
This is the number of seconds to wait for an acknowledgement to a packet\n\
|
||
before resending the packet.", &setlist),
|
||
&showlist);
|
||
}
|