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, see <http://www.gnu.org/licenses/>. *
  17  ***************************************************************************/
  18
  19 #ifdef HAVE_CONFIG_H
  20 #include "config.h"
  21 #endif
  22
  23 #ifndef _WIN32
  24 #include <sys/un.h>
  25 #include <netdb.h>
  26 #endif
  27 #include <jtag/interface.h>
  28 #include "bitbang.h"
  29
  30 /* arbitrary limit on host name length: */
  31 #define REMOTE_BITBANG_HOST_MAX 255
  32
  33 #define REMOTE_BITBANG_RAISE_ERROR(expr ...) \
  34         do { \
  35                 LOG_ERROR(expr); \
  36                 LOG_ERROR("Terminating openocd."); \
  37                 exit(-1); \
  38         } while (0)
  39
  40 static char *remote_bitbang_host;
  41 static char *remote_bitbang_port;
  42
  43 FILE *remote_bitbang_in;
  44 FILE *remote_bitbang_out;
  45
  46 static void remote_bitbang_putc(int c)
  47 {
  48         if (EOF == fputc(c, remote_bitbang_out))
  49                 REMOTE_BITBANG_RAISE_ERROR("remote_bitbang_putc: %s", strerror(errno));
  50 }
  51
  52 static int remote_bitbang_quit(void)
  53 {
  54         if (EOF == fputc('Q', remote_bitbang_out)) {
  55                 LOG_ERROR("fputs: %s", strerror(errno));
  56                 return ERROR_FAIL;
  57         }
  58
  59         if (EOF == fflush(remote_bitbang_out)) {
  60                 LOG_ERROR("fflush: %s", strerror(errno));
  61                 return ERROR_FAIL;
  62         }
  63
  64         /* We only need to close one of the FILE*s, because they both use the same */
  65         /* underlying file descriptor. */
  66         if (EOF == fclose(remote_bitbang_out)) {
  67                 LOG_ERROR("fclose: %s", strerror(errno));
  68                 return ERROR_FAIL;
  69         }
  70
  71         free(remote_bitbang_host);
  72         free(remote_bitbang_port);
  73
  74         LOG_INFO("remote_bitbang interface quit");
  75         return ERROR_OK;
  76 }
  77
  78 /* Get the next read response. */
  79 static int remote_bitbang_rread(void)
  80 {
  81         if (EOF == fflush(remote_bitbang_out)) {
  82                 remote_bitbang_quit();
  83                 REMOTE_BITBANG_RAISE_ERROR("fflush: %s", strerror(errno));
  84         }
  85
  86         int c = fgetc(remote_bitbang_in);
  87         switch (c) {
  88                 case '0':
  89                         return 0;
  90                 case '1':
  91                         return 1;
  92                 default:
  93                         remote_bitbang_quit();
  94                         REMOTE_BITBANG_RAISE_ERROR(
  95                                         "remote_bitbang: invalid read response: %c(%i)", c, c);
  96         }
  97 }
  98
  99 static int remote_bitbang_read(void)
 100 {
 101         remote_bitbang_putc('R');
 102         return remote_bitbang_rread();
 103 }
 104
 105 static void remote_bitbang_write(int tck, int tms, int tdi)
 106 {
 107         char c = '0' + ((tck ? 0x4 : 0x0) | (tms ? 0x2 : 0x0) | (tdi ? 0x1 : 0x0));
 108         remote_bitbang_putc(c);
 109 }
 110
 111 static void remote_bitbang_reset(int trst, int srst)
 112 {
 113         char c = 'r' + ((trst ? 0x2 : 0x0) | (srst ? 0x1 : 0x0));
 114         remote_bitbang_putc(c);
 115 }
 116
 117 static void remote_bitbang_blink(int on)
 118 {
 119         char c = on ? 'B' : 'b';
 120         remote_bitbang_putc(c);
 121 }
 122
 123 static struct bitbang_interface remote_bitbang_bitbang = {
 124         .read = &remote_bitbang_read,
 125         .write = &remote_bitbang_write,
 126         .reset = &remote_bitbang_reset,
 127         .blink = &remote_bitbang_blink,
 128 };
 129
 130 static int remote_bitbang_init_tcp(void)
 131 {
 132         struct addrinfo hints = { .ai_family = AF_UNSPEC, .ai_socktype = SOCK_STREAM };
 133         struct addrinfo *result, *rp;
 134         int fd;
 135
 136         LOG_INFO("Connecting to %s:%s",
 137                         remote_bitbang_host ? remote_bitbang_host : "localhost",
 138                         remote_bitbang_port);
 139
 140         /* Obtain address(es) matching host/port */
 141         int s = getaddrinfo(remote_bitbang_host, remote_bitbang_port, &hints, &result);
 142         if (s != 0) {
 143                 LOG_ERROR("getaddrinfo: %s\n", gai_strerror(s));
 144                 return ERROR_FAIL;
 145         }
 146
 147         /* getaddrinfo() returns a list of address structures.
 148          Try each address until we successfully connect(2).
 149          If socket(2) (or connect(2)) fails, we (close the socket
 150          and) try the next address. */
 151
 152         for (rp = result; rp != NULL ; rp = rp->ai_next) {
 153                 fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
 154                 if (fd == -1)
 155                         continue;
 156
 157                 if (connect(fd, rp->ai_addr, rp->ai_addrlen) != -1)
 158                         break; /* Success */
 159
 160                 close(fd);
 161         }
 162
 163         freeaddrinfo(result); /* No longer needed */
 164
 165         if (rp == NULL) { /* No address succeeded */
 166                 LOG_ERROR("Failed to connect: %s", strerror(errno));
 167                 return ERROR_FAIL;
 168         }
 169
 170         return fd;
 171 }
 172
 173 static int remote_bitbang_init_unix(void)
 174 {
 175         if (remote_bitbang_host == NULL) {
 176                 LOG_ERROR("host/socket not specified");
 177                 return ERROR_FAIL;
 178         }
 179
 180         LOG_INFO("Connecting to unix socket %s", remote_bitbang_host);
 181         int fd = socket(PF_UNIX, SOCK_STREAM, 0);
 182         if (fd < 0) {
 183                 LOG_ERROR("socket: %s", strerror(errno));
 184                 return ERROR_FAIL;
 185         }
 186
 187         struct sockaddr_un addr;
 188         addr.sun_family = AF_UNIX;
 189         strncpy(addr.sun_path, remote_bitbang_host, sizeof(addr.sun_path));
 190         addr.sun_path[sizeof(addr.sun_path)-1] = '\0';
 191
 192         if (connect(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0) {
 193                 LOG_ERROR("connect: %s", strerror(errno));
 194                 return ERROR_FAIL;
 195         }
 196
 197         return fd;
 198 }
 199
 200 static int remote_bitbang_init(void)
 201 {
 202         int fd;
 203         bitbang_interface = &remote_bitbang_bitbang;
 204
 205         LOG_INFO("Initializing remote_bitbang driver");
 206         if (remote_bitbang_port == NULL)
 207                 fd = remote_bitbang_init_unix();
 208         else
 209                 fd = remote_bitbang_init_tcp();
 210
 211         if (fd < 0)
 212                 return fd;
 213
 214         remote_bitbang_in = fdopen(fd, "r");
 215         if (remote_bitbang_in == NULL) {
 216                 LOG_ERROR("fdopen: failed to open read stream");
 217                 close(fd);
 218                 return ERROR_FAIL;
 219         }
 220
 221         remote_bitbang_out = fdopen(fd, "w");
 222         if (remote_bitbang_out == NULL) {
 223                 LOG_ERROR("fdopen: failed to open write stream");
 224                 fclose(remote_bitbang_in);
 225                 return ERROR_FAIL;
 226         }
 227
 228         LOG_INFO("remote_bitbang driver initialized");
 229         return ERROR_OK;
 230 }
 231
 232 COMMAND_HANDLER(remote_bitbang_handle_remote_bitbang_port_command)
 233 {
 234         if (CMD_ARGC == 1) {
 235                 uint16_t port;
 236                 COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], port);
 237                 free(remote_bitbang_port);
 238                 remote_bitbang_port = port == 0 ? NULL : strdup(CMD_ARGV[0]);
 239                 return ERROR_OK;
 240         }
 241         return ERROR_COMMAND_SYNTAX_ERROR;
 242 }
 243
 244 COMMAND_HANDLER(remote_bitbang_handle_remote_bitbang_host_command)
 245 {
 246         if (CMD_ARGC == 1) {
 247                 free(remote_bitbang_host);
 248                 remote_bitbang_host = strdup(CMD_ARGV[0]);
 249                 return ERROR_OK;
 250         }
 251         return ERROR_COMMAND_SYNTAX_ERROR;
 252 }
 253
 254 static const struct command_registration remote_bitbang_command_handlers[] = {
 255         {
 256                 .name = "remote_bitbang_port",
 257                 .handler = remote_bitbang_handle_remote_bitbang_port_command,
 258                 .mode = COMMAND_CONFIG,
 259                 .help = "Set the port to use to connect to the remote jtag.\n"
 260                         "  if 0 or unset, use unix sockets to connect to the remote jtag.",
 261                 .usage = "port_number",
 262         },
 263         {
 264                 .name = "remote_bitbang_host",
 265                 .handler = remote_bitbang_handle_remote_bitbang_host_command,
 266                 .mode = COMMAND_CONFIG,
 267                 .help = "Set the host to use to connect to the remote jtag.\n"
 268                         "  if port is 0 or unset, this is the name of the unix socket to use.",
 269                 .usage = "host_name",
 270         },
 271         COMMAND_REGISTRATION_DONE,
 272 };
 273
 274 struct jtag_interface remote_bitbang_interface = {
 275         .name = "remote_bitbang",
 276         .execute_queue = &bitbang_execute_queue,
 277         .commands = remote_bitbang_command_handlers,
 278         .init = &remote_bitbang_init,
 279         .quit = &remote_bitbang_quit,
 280 };