src/jtag/drivers/remote_bitbang.c

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Richard Uhler                                   *
   3  *   ruhler@mit.edu                                                        *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
  19  ***************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 #include "config.h"
  23 #endif
  24
  25 #ifndef _WIN32
  26 #include <sys/un.h>
  27 #include <netdb.h>
  28 #endif
  29 #include <jtag/interface.h>
  30 #include "bitbang.h"
  31
  32 /* arbitrary limit on host name length: */
  33 #define REMOTE_BITBANG_HOST_MAX 255
  34
  35 #define REMOTE_BITBANG_RAISE_ERROR(expr ...) \
  36         do { \
  37                 LOG_ERROR(expr); \
  38                 LOG_ERROR("Terminating openocd."); \
  39                 exit(-1); \
  40         } while (0)
  41
  42 static char *remote_bitbang_host;
  43 static char *remote_bitbang_port;
  44
  45 FILE *remote_bitbang_in;
  46 FILE *remote_bitbang_out;
  47
  48 static void remote_bitbang_putc(int c)
  49 {
  50         if (EOF == fputc(c, remote_bitbang_out))
  51                 REMOTE_BITBANG_RAISE_ERROR("remote_bitbang_putc: %s", strerror(errno));
  52 }
  53
  54 static int remote_bitbang_quit(void)
  55 {
  56         if (EOF == fputc('Q', remote_bitbang_out)) {
  57                 LOG_ERROR("fputs: %s", strerror(errno));
  58                 return ERROR_FAIL;
  59         }
  60
  61         if (EOF == fflush(remote_bitbang_out)) {
  62                 LOG_ERROR("fflush: %s", strerror(errno));
  63                 return ERROR_FAIL;
  64         }
  65
  66         /* We only need to close one of the FILE*s, because they both use the same */
  67         /* underlying file descriptor. */
  68         if (EOF == fclose(remote_bitbang_out)) {
  69                 LOG_ERROR("fclose: %s", strerror(errno));
  70                 return ERROR_FAIL;
  71         }
  72
  73         free(remote_bitbang_host);
  74         free(remote_bitbang_port);
  75
  76         LOG_INFO("remote_bitbang interface quit");
  77         return ERROR_OK;
  78 }
  79
  80 /* Get the next read response. */
  81 static int remote_bitbang_rread(void)
  82 {
  83         if (EOF == fflush(remote_bitbang_out)) {
  84                 remote_bitbang_quit();
  85                 REMOTE_BITBANG_RAISE_ERROR("fflush: %s", strerror(errno));
  86         }
  87
  88         int c = fgetc(remote_bitbang_in);
  89         switch (c) {
  90                 case '0':
  91                         return 0;
  92                 case '1':
  93                         return 1;
  94                 default:
  95                         remote_bitbang_quit();
  96                         REMOTE_BITBANG_RAISE_ERROR(
  97                                         "remote_bitbang: invalid read response: %c(%i)", c, c);
  98         }
  99 }
 100
 101 static int remote_bitbang_read(void)
 102 {
 103         remote_bitbang_putc('R');
 104         return remote_bitbang_rread();
 105 }
 106
 107 static void remote_bitbang_write(int tck, int tms, int tdi)
 108 {
 109         char c = '0' + ((tck ? 0x4 : 0x0) | (tms ? 0x2 : 0x0) | (tdi ? 0x1 : 0x0));
 110         remote_bitbang_putc(c);
 111 }
 112
 113 static void remote_bitbang_reset(int trst, int srst)
 114 {
 115         char c = 'r' + ((trst ? 0x2 : 0x0) | (srst ? 0x1 : 0x0));
 116         remote_bitbang_putc(c);
 117 }
 118
 119 static void remote_bitbang_blink(int on)
 120 {
 121         char c = on ? 'B' : 'b';
 122         remote_bitbang_putc(c);
 123 }
 124
 125 static struct bitbang_interface remote_bitbang_bitbang = {
 126         .read = &remote_bitbang_read,
 127         .write = &remote_bitbang_write,
 128         .reset = &remote_bitbang_reset,
 129         .blink = &remote_bitbang_blink,
 130 };
 131
 132 static int remote_bitbang_init_tcp(void)
 133 {
 134         struct addrinfo hints = { .ai_family = AF_UNSPEC, .ai_socktype = SOCK_STREAM };
 135         struct addrinfo *result, *rp;
 136         int fd;
 137
 138         LOG_INFO("Connecting to %s:%s",
 139                         remote_bitbang_host ? remote_bitbang_host : "localhost",
 140                         remote_bitbang_port);
 141
 142         /* Obtain address(es) matching host/port */
 143         int s = getaddrinfo(remote_bitbang_host, remote_bitbang_port, &hints, &result);
 144         if (s != 0) {
 145                 LOG_ERROR("getaddrinfo: %s\n", gai_strerror(s));
 146                 return ERROR_FAIL;
 147         }
 148
 149         /* getaddrinfo() returns a list of address structures.
 150          Try each address until we successfully connect(2).
 151          If socket(2) (or connect(2)) fails, we (close the socket
 152          and) try the next address. */
 153
 154         for (rp = result; rp != NULL ; rp = rp->ai_next) {
 155                 fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
 156                 if (fd == -1)
 157                         continue;
 158
 159                 if (connect(fd, rp->ai_addr, rp->ai_addrlen) != -1)
 160                         break; /* Success */
 161
 162                 close(fd);
 163         }
 164
 165         freeaddrinfo(result); /* No longer needed */
 166
 167         if (rp == NULL) { /* No address succeeded */
 168                 LOG_ERROR("Failed to connect: %s", strerror(errno));
 169                 return ERROR_FAIL;
 170         }
 171
 172         return fd;
 173 }
 174
 175 static int remote_bitbang_init_unix(void)
 176 {
 177         if (remote_bitbang_host == NULL) {
 178                 LOG_ERROR("host/socket not specified");
 179                 return ERROR_FAIL;
 180         }
 181
 182         LOG_INFO("Connecting to unix socket %s", remote_bitbang_host);
 183         int fd = socket(PF_UNIX, SOCK_STREAM, 0);
 184         if (fd < 0) {
 185                 LOG_ERROR("socket: %s", strerror(errno));
 186                 return ERROR_FAIL;
 187         }
 188
 189         struct sockaddr_un addr;
 190         addr.sun_family = AF_UNIX;
 191         strncpy(addr.sun_path, remote_bitbang_host, sizeof(addr.sun_path));
 192         addr.sun_path[sizeof(addr.sun_path)-1] = '\0';
 193
 194         if (connect(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0) {
 195                 LOG_ERROR("connect: %s", strerror(errno));
 196                 return ERROR_FAIL;
 197         }
 198
 199         return fd;
 200 }
 201
 202 static int remote_bitbang_init(void)
 203 {
 204         int fd;
 205         bitbang_interface = &remote_bitbang_bitbang;
 206
 207         LOG_INFO("Initializing remote_bitbang driver");
 208         if (remote_bitbang_port == NULL)
 209                 fd = remote_bitbang_init_unix();
 210         else
 211                 fd = remote_bitbang_init_tcp();
 212
 213         if (fd < 0)
 214                 return fd;
 215
 216         remote_bitbang_in = fdopen(fd, "r");
 217         if (remote_bitbang_in == NULL) {
 218                 LOG_ERROR("fdopen: failed to open read stream");
 219                 close(fd);
 220                 return ERROR_FAIL;
 221         }
 222
 223         remote_bitbang_out = fdopen(fd, "w");
 224         if (remote_bitbang_out == NULL) {
 225                 LOG_ERROR("fdopen: failed to open write stream");
 226                 fclose(remote_bitbang_in);
 227                 return ERROR_FAIL;
 228         }
 229
 230         LOG_INFO("remote_bitbang driver initialized");
 231         return ERROR_OK;
 232 }
 233
 234 COMMAND_HANDLER(remote_bitbang_handle_remote_bitbang_port_command)
 235 {
 236         if (CMD_ARGC == 1) {
 237                 uint16_t port;
 238                 COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], port);
 239                 free(remote_bitbang_port);
 240                 remote_bitbang_port = port == 0 ? NULL : strdup(CMD_ARGV[0]);
 241                 return ERROR_OK;
 242         }
 243         return ERROR_COMMAND_SYNTAX_ERROR;
 244 }
 245
 246 COMMAND_HANDLER(remote_bitbang_handle_remote_bitbang_host_command)
 247 {
 248         if (CMD_ARGC == 1) {
 249                 free(remote_bitbang_host);
 250                 remote_bitbang_host = strdup(CMD_ARGV[0]);
 251                 return ERROR_OK;
 252         }
 253         return ERROR_COMMAND_SYNTAX_ERROR;
 254 }
 255
 256 static const struct command_registration remote_bitbang_command_handlers[] = {
 257         {
 258                 .name = "remote_bitbang_port",
 259                 .handler = remote_bitbang_handle_remote_bitbang_port_command,
 260                 .mode = COMMAND_CONFIG,
 261                 .help = "Set the port to use to connect to the remote jtag.\n"
 262                         "  if 0 or unset, use unix sockets to connect to the remote jtag.",
 263                 .usage = "port_number",
 264         },
 265         {
 266                 .name = "remote_bitbang_host",
 267                 .handler = remote_bitbang_handle_remote_bitbang_host_command,
 268                 .mode = COMMAND_CONFIG,
 269                 .help = "Set the host to use to connect to the remote jtag.\n"
 270                         "  if port is 0 or unset, this is the name of the unix socket to use.",
 271                 .usage = "host_name",
 272         },
 273         COMMAND_REGISTRATION_DONE,
 274 };
 275
 276 struct jtag_interface remote_bitbang_interface = {
 277         .name = "remote_bitbang",
 278         .execute_queue = &bitbang_execute_queue,
 279         .commands = remote_bitbang_command_handlers,
 280         .init = &remote_bitbang_init,
 281         .quit = &remote_bitbang_quit,
 282 };