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 #ifndef UNIX_PATH_LEN
  33 #define UNIX_PATH_LEN 108
  34 #endif
  35
  36 /* arbitrary limit on host name length: */
  37 #define REMOTE_BITBANG_HOST_MAX 255
  38
  39 #define REMOTE_BITBANG_RAISE_ERROR(expr ...) \
  40         do { \
  41                 LOG_ERROR(expr); \
  42                 LOG_ERROR("Terminating openocd."); \
  43                 exit(-1); \
  44         } while (0)
  45
  46 static char *remote_bitbang_host;
  47 static char *remote_bitbang_port;
  48
  49 FILE *remote_bitbang_in;
  50 FILE *remote_bitbang_out;
  51
  52 static void remote_bitbang_putc(int c)
  53 {
  54         if (EOF == fputc(c, remote_bitbang_out))
  55                 REMOTE_BITBANG_RAISE_ERROR("remote_bitbang_putc: %s", strerror(errno));
  56 }
  57
  58 static int remote_bitbang_quit(void)
  59 {
  60         if (EOF == fputc('Q', remote_bitbang_out)) {
  61                 LOG_ERROR("fputs: %s", strerror(errno));
  62                 return ERROR_FAIL;
  63         }
  64
  65         if (EOF == fflush(remote_bitbang_out)) {
  66                 LOG_ERROR("fflush: %s", strerror(errno));
  67                 return ERROR_FAIL;
  68         }
  69
  70         /* We only need to close one of the FILE*s, because they both use the same */
  71         /* underlying file descriptor. */
  72         if (EOF == fclose(remote_bitbang_out)) {
  73                 LOG_ERROR("fclose: %s", strerror(errno));
  74                 return ERROR_FAIL;
  75         }
  76
  77         free(remote_bitbang_host);
  78         free(remote_bitbang_port);
  79
  80         LOG_INFO("remote_bitbang interface quit");
  81         return ERROR_OK;
  82 }
  83
  84 /* Get the next read response. */
  85 static int remote_bitbang_rread(void)
  86 {
  87         if (EOF == fflush(remote_bitbang_out)) {
  88                 remote_bitbang_quit();
  89                 REMOTE_BITBANG_RAISE_ERROR("fflush: %s", strerror(errno));
  90         }
  91
  92         int c = fgetc(remote_bitbang_in);
  93         switch (c) {
  94                 case '0':
  95                         return 0;
  96                 case '1':
  97                         return 1;
  98                 default:
  99                         remote_bitbang_quit();
 100                         REMOTE_BITBANG_RAISE_ERROR(
 101                                         "remote_bitbang: invalid read response: %c(%i)", c, c);
 102         }
 103 }
 104
 105 static int remote_bitbang_read(void)
 106 {
 107         remote_bitbang_putc('R');
 108         return remote_bitbang_rread();
 109 }
 110
 111 static void remote_bitbang_write(int tck, int tms, int tdi)
 112 {
 113         char c = '0' + ((tck ? 0x4 : 0x0) | (tms ? 0x2 : 0x0) | (tdi ? 0x1 : 0x0));
 114         remote_bitbang_putc(c);
 115 }
 116
 117 static void remote_bitbang_reset(int trst, int srst)
 118 {
 119         char c = 'r' + ((trst ? 0x2 : 0x0) | (srst ? 0x1 : 0x0));
 120         remote_bitbang_putc(c);
 121 }
 122
 123 static void remote_bitbang_blink(int on)
 124 {
 125         char c = on ? 'B' : 'b';
 126         remote_bitbang_putc(c);
 127 }
 128
 129 static struct bitbang_interface remote_bitbang_bitbang = {
 130         .read = &remote_bitbang_read,
 131         .write = &remote_bitbang_write,
 132         .reset = &remote_bitbang_reset,
 133         .blink = &remote_bitbang_blink,
 134 };
 135
 136 static int remote_bitbang_init_tcp(void)
 137 {
 138         struct addrinfo hints = { .ai_family = AF_UNSPEC, .ai_socktype = SOCK_STREAM };
 139         struct addrinfo *result, *rp;
 140         int fd;
 141
 142         LOG_INFO("Connecting to %s:%s",
 143                         remote_bitbang_host ? remote_bitbang_host : "localhost",
 144                         remote_bitbang_port);
 145
 146         /* Obtain address(es) matching host/port */
 147         int s = getaddrinfo(remote_bitbang_host, remote_bitbang_port, &hints, &result);
 148         if (s != 0) {
 149                 LOG_ERROR("getaddrinfo: %s\n", gai_strerror(s));
 150                 return ERROR_FAIL;
 151         }
 152
 153         /* getaddrinfo() returns a list of address structures.
 154          Try each address until we successfully connect(2).
 155          If socket(2) (or connect(2)) fails, we (close the socket
 156          and) try the next address. */
 157
 158         for (rp = result; rp != NULL ; rp = rp->ai_next) {
 159                 fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
 160                 if (fd == -1)
 161                         continue;
 162
 163                 if (connect(fd, rp->ai_addr, rp->ai_addrlen) != -1)
 164                         break; /* Success */
 165
 166                 close(fd);
 167         }
 168
 169         freeaddrinfo(result); /* No longer needed */
 170
 171         if (rp == NULL) { /* No address succeeded */
 172                 LOG_ERROR("Failed to connect: %s", strerror(errno));
 173                 return ERROR_FAIL;
 174         }
 175
 176         return fd;
 177 }
 178
 179 static int remote_bitbang_init_unix(void)
 180 {
 181         if (remote_bitbang_host == NULL) {
 182                 LOG_ERROR("host/socket not specified");
 183                 return ERROR_FAIL;
 184         }
 185
 186         LOG_INFO("Connecting to unix socket %s", remote_bitbang_host);
 187         int fd = socket(PF_UNIX, SOCK_STREAM, 0);
 188         if (fd < 0) {
 189                 LOG_ERROR("socket: %s", strerror(errno));
 190                 return ERROR_FAIL;
 191         }
 192
 193         struct sockaddr_un addr;
 194         addr.sun_family = AF_UNIX;
 195         strncpy(addr.sun_path, remote_bitbang_host, UNIX_PATH_LEN);
 196         addr.sun_path[UNIX_PATH_LEN-1] = '\0';
 197
 198         if (connect(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0) {
 199                 LOG_ERROR("connect: %s", strerror(errno));
 200                 return ERROR_FAIL;
 201         }
 202
 203         return fd;
 204 }
 205
 206 static int remote_bitbang_init(void)
 207 {
 208         int fd;
 209         bitbang_interface = &remote_bitbang_bitbang;
 210
 211         LOG_INFO("Initializing remote_bitbang driver");
 212         if (remote_bitbang_port == NULL)
 213                 fd = remote_bitbang_init_unix();
 214         else
 215                 fd = remote_bitbang_init_tcp();
 216
 217         if (fd < 0)
 218                 return fd;
 219
 220         remote_bitbang_in = fdopen(fd, "r");
 221         if (remote_bitbang_in == NULL) {
 222                 LOG_ERROR("fdopen: failed to open read stream");
 223                 close(fd);
 224                 return ERROR_FAIL;
 225         }
 226
 227         remote_bitbang_out = fdopen(fd, "w");
 228         if (remote_bitbang_out == NULL) {
 229                 LOG_ERROR("fdopen: failed to open write stream");
 230                 fclose(remote_bitbang_in);
 231                 return ERROR_FAIL;
 232         }
 233
 234         LOG_INFO("remote_bitbang driver initialized");
 235         return ERROR_OK;
 236 }
 237
 238 COMMAND_HANDLER(remote_bitbang_handle_remote_bitbang_port_command)
 239 {
 240         if (CMD_ARGC == 1) {
 241                 uint16_t port;
 242                 COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], port);
 243                 free(remote_bitbang_port);
 244                 remote_bitbang_port = port == 0 ? NULL : strdup(CMD_ARGV[0]);
 245                 return ERROR_OK;
 246         }
 247         return ERROR_COMMAND_SYNTAX_ERROR;
 248 }
 249
 250 COMMAND_HANDLER(remote_bitbang_handle_remote_bitbang_host_command)
 251 {
 252         if (CMD_ARGC == 1) {
 253                 free(remote_bitbang_host);
 254                 remote_bitbang_host = strdup(CMD_ARGV[0]);
 255                 return ERROR_OK;
 256         }
 257         return ERROR_COMMAND_SYNTAX_ERROR;
 258 }
 259
 260 static const struct command_registration remote_bitbang_command_handlers[] = {
 261         {
 262                 .name = "remote_bitbang_port",
 263                 .handler = remote_bitbang_handle_remote_bitbang_port_command,
 264                 .mode = COMMAND_CONFIG,
 265                 .help = "Set the port to use to connect to the remote jtag.\n"
 266                         "  if 0 or unset, use unix sockets to connect to the remote jtag.",
 267                 .usage = "port_number",
 268         },
 269         {
 270                 .name = "remote_bitbang_host",
 271                 .handler = remote_bitbang_handle_remote_bitbang_host_command,
 272                 .mode = COMMAND_CONFIG,
 273                 .help = "Set the host to use to connect to the remote jtag.\n"
 274                         "  if port is 0 or unset, this is the name of the unix socket to use.",
 275                 .usage = "host_name",
 276         },
 277         COMMAND_REGISTRATION_DONE,
 278 };
 279
 280 struct jtag_interface remote_bitbang_interface = {
 281         .name = "remote_bitbang",
 282         .execute_queue = &bitbang_execute_queue,
 283         .commands = remote_bitbang_command_handlers,
 284         .init = &remote_bitbang_init,
 285         .quit = &remote_bitbang_quit,
 286 };