drivers/serial/serial.c

   1 /*
   2  * (C) Copyright 2004
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <common.h>
  25 #include <serial.h>
  26 #include <stdio_dev.h>
  27 #include <post.h>
  28 #include <linux/compiler.h>
  29 #include <errno.h>
  30
  31 DECLARE_GLOBAL_DATA_PTR;
  32
  33 static struct serial_device *serial_devices;
  34 static struct serial_device *serial_current;
  35
  36 /**
  37  * serial_null() - Void registration routine of a serial driver
  38  *
  39  * This routine implements a void registration routine of a serial
  40  * driver. The registration routine of a particular driver is aliased
  41  * to this empty function in case the driver is not compiled into
  42  * U-Boot.
  43  */
  44 static void serial_null(void)
  45 {
  46 }
  47
  48 /**
  49  * serial_initfunc() - Forward declare of driver registration routine
  50  * @name:       Name of the real driver registration routine.
  51  *
  52  * This macro expands onto forward declaration of a driver registration
  53  * routine, which is then used below in serial_initialize() function.
  54  * The declaration is made weak and aliases to serial_null() so in case
  55  * the driver is not compiled in, the function is still declared and can
  56  * be used, but aliases to serial_null() and thus is optimized away.
  57  */
  58 #define serial_initfunc(name)                                   \
  59         void name(void)                                         \
  60                 __attribute__((weak, alias("serial_null")));
  61
  62 serial_initfunc(mpc8xx_serial_initialize);
  63 serial_initfunc(ns16550_serial_initialize);
  64 serial_initfunc(pxa_serial_initialize);
  65 serial_initfunc(s3c24xx_serial_initialize);
  66 serial_initfunc(s5p_serial_initialize);
  67 serial_initfunc(zynq_serial_initalize);
  68 serial_initfunc(bfin_serial_initialize);
  69 serial_initfunc(bfin_jtag_initialize);
  70 serial_initfunc(mpc512x_serial_initialize);
  71 serial_initfunc(uartlite_serial_initialize);
  72 serial_initfunc(au1x00_serial_initialize);
  73 serial_initfunc(asc_serial_initialize);
  74 serial_initfunc(jz_serial_initialize);
  75 serial_initfunc(mpc5xx_serial_initialize);
  76 serial_initfunc(mpc8220_serial_initialize);
  77 serial_initfunc(mpc8260_scc_serial_initialize);
  78 serial_initfunc(mpc8260_smc_serial_initialize);
  79 serial_initfunc(mpc85xx_serial_initialize);
  80 serial_initfunc(iop480_serial_initialize);
  81 serial_initfunc(leon2_serial_initialize);
  82 serial_initfunc(leon3_serial_initialize);
  83 serial_initfunc(marvell_serial_initialize);
  84 serial_initfunc(amirix_serial_initialize);
  85 serial_initfunc(bmw_serial_initialize);
  86 serial_initfunc(cogent_serial_initialize);
  87 serial_initfunc(cpci750_serial_initialize);
  88 serial_initfunc(evb64260_serial_initialize);
  89 serial_initfunc(ml2_serial_initialize);
  90 serial_initfunc(sconsole_serial_initialize);
  91 serial_initfunc(p3mx_serial_initialize);
  92 serial_initfunc(altera_jtag_serial_initialize);
  93 serial_initfunc(altera_serial_initialize);
  94 serial_initfunc(atmel_serial_initialize);
  95 serial_initfunc(lpc32xx_serial_initialize);
  96 serial_initfunc(mcf_serial_initialize);
  97 serial_initfunc(ns9750_serial_initialize);
  98 serial_initfunc(oc_serial_initialize);
  99 serial_initfunc(s3c4510b_serial_initialize);
 100 serial_initfunc(s3c64xx_serial_initialize);
 101 serial_initfunc(sandbox_serial_initialize);
 102 serial_initfunc(clps7111_serial_initialize);
 103 serial_initfunc(imx_serial_initialize);
 104 serial_initfunc(ixp_serial_initialize);
 105 serial_initfunc(ks8695_serial_initialize);
 106 serial_initfunc(lh7a40x_serial_initialize);
 107 serial_initfunc(lpc2292_serial_initialize);
 108 serial_initfunc(max3100_serial_initialize);
 109 serial_initfunc(mxc_serial_initialize);
 110 serial_initfunc(netarm_serial_initialize);
 111 serial_initfunc(pl01x_serial_initialize);
 112 serial_initfunc(s3c44b0_serial_initialize);
 113 serial_initfunc(sa1100_serial_initialize);
 114 serial_initfunc(sh_serial_initialize);
 115
 116 /**
 117  * serial_register() - Register serial driver with serial driver core
 118  * @dev:        Pointer to the serial driver structure
 119  *
 120  * This function registers the serial driver supplied via @dev with
 121  * serial driver core, thus making U-Boot aware of it and making it
 122  * available for U-Boot to use. On platforms that still require manual
 123  * relocation of constant variables, relocation of the supplied structure
 124  * is performed.
 125  */
 126 void serial_register(struct serial_device *dev)
 127 {
 128 #ifdef CONFIG_NEEDS_MANUAL_RELOC
 129         if (dev->start)
 130                 dev->start += gd->reloc_off;
 131         if (dev->stop)
 132                 dev->stop += gd->reloc_off;
 133         if (dev->setbrg)
 134                 dev->setbrg += gd->reloc_off;
 135         if (dev->getc)
 136                 dev->getc += gd->reloc_off;
 137         if (dev->tstc)
 138                 dev->tstc += gd->reloc_off;
 139         if (dev->putc)
 140                 dev->putc += gd->reloc_off;
 141         if (dev->puts)
 142                 dev->puts += gd->reloc_off;
 143 #endif
 144
 145         dev->next = serial_devices;
 146         serial_devices = dev;
 147 }
 148
 149 /**
 150  * serial_initialize() - Register all compiled-in serial port drivers
 151  *
 152  * This function registers all serial port drivers that are compiled
 153  * into the U-Boot binary with the serial core, thus making them
 154  * available to U-Boot to use. Lastly, this function assigns a default
 155  * serial port to the serial core. That serial port is then used as a
 156  * default output.
 157  */
 158 void serial_initialize(void)
 159 {
 160         mpc8xx_serial_initialize();
 161         ns16550_serial_initialize();
 162         pxa_serial_initialize();
 163         s3c24xx_serial_initialize();
 164         s5p_serial_initialize();
 165         mpc512x_serial_initialize();
 166         bfin_serial_initialize();
 167         bfin_jtag_initialize();
 168         uartlite_serial_initialize();
 169         zynq_serial_initalize();
 170         au1x00_serial_initialize();
 171         asc_serial_initialize();
 172         jz_serial_initialize();
 173         mpc5xx_serial_initialize();
 174         mpc8220_serial_initialize();
 175         mpc8260_scc_serial_initialize();
 176         mpc8260_smc_serial_initialize();
 177         mpc85xx_serial_initialize();
 178         iop480_serial_initialize();
 179         leon2_serial_initialize();
 180         leon3_serial_initialize();
 181         marvell_serial_initialize();
 182         amirix_serial_initialize();
 183         bmw_serial_initialize();
 184         cogent_serial_initialize();
 185         cpci750_serial_initialize();
 186         evb64260_serial_initialize();
 187         ml2_serial_initialize();
 188         sconsole_serial_initialize();
 189         p3mx_serial_initialize();
 190         altera_jtag_serial_initialize();
 191         altera_serial_initialize();
 192         atmel_serial_initialize();
 193         lpc32xx_serial_initialize();
 194         mcf_serial_initialize();
 195         ns9750_serial_initialize();
 196         oc_serial_initialize();
 197         s3c4510b_serial_initialize();
 198         s3c64xx_serial_initialize();
 199         sandbox_serial_initialize();
 200         clps7111_serial_initialize();
 201         imx_serial_initialize();
 202         ixp_serial_initialize();
 203         ks8695_serial_initialize();
 204         lh7a40x_serial_initialize();
 205         lpc2292_serial_initialize();
 206         max3100_serial_initialize();
 207         mxc_serial_initialize();
 208         netarm_serial_initialize();
 209         pl01x_serial_initialize();
 210         s3c44b0_serial_initialize();
 211         sa1100_serial_initialize();
 212         sh_serial_initialize();
 213
 214         serial_assign(default_serial_console()->name);
 215 }
 216
 217 /**
 218  * serial_stdio_init() - Register serial ports with STDIO core
 219  *
 220  * This function generates a proxy driver for each serial port driver.
 221  * These proxy drivers then register with the STDIO core, making the
 222  * serial drivers available as STDIO devices.
 223  */
 224 void serial_stdio_init(void)
 225 {
 226         struct stdio_dev dev;
 227         struct serial_device *s = serial_devices;
 228
 229         while (s) {
 230                 memset(&dev, 0, sizeof(dev));
 231
 232                 strcpy(dev.name, s->name);
 233                 dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT;
 234
 235                 dev.start = s->start;
 236                 dev.stop = s->stop;
 237                 dev.putc = s->putc;
 238                 dev.puts = s->puts;
 239                 dev.getc = s->getc;
 240                 dev.tstc = s->tstc;
 241
 242                 stdio_register(&dev);
 243
 244                 s = s->next;
 245         }
 246 }
 247
 248 /**
 249  * serial_assign() - Select the serial output device by name
 250  * @name:       Name of the serial driver to be used as default output
 251  *
 252  * This function configures the serial output multiplexing by
 253  * selecting which serial device will be used as default. In case
 254  * the STDIO "serial" device is selected as stdin/stdout/stderr,
 255  * the serial device previously configured by this function will be
 256  * used for the particular operation.
 257  *
 258  * Returns 0 on success, negative on error.
 259  */
 260 int serial_assign(const char *name)
 261 {
 262         struct serial_device *s;
 263
 264         for (s = serial_devices; s; s = s->next) {
 265                 if (strcmp(s->name, name))
 266                         continue;
 267                 serial_current = s;
 268                 return 0;
 269         }
 270
 271         return -EINVAL;
 272 }
 273
 274 /**
 275  * serial_reinit_all() - Reinitialize all compiled-in serial ports
 276  *
 277  * This function reinitializes all serial ports that are compiled
 278  * into U-Boot by calling their serial_start() functions.
 279  */
 280 void serial_reinit_all(void)
 281 {
 282         struct serial_device *s;
 283
 284         for (s = serial_devices; s; s = s->next)
 285                 s->start();
 286 }
 287
 288 /**
 289  * get_current() - Return pointer to currently selected serial port
 290  *
 291  * This function returns a pointer to currently selected serial port.
 292  * The currently selected serial port is altered by serial_assign()
 293  * function.
 294  *
 295  * In case this function is called before relocation or before any serial
 296  * port is configured, this function calls default_serial_console() to
 297  * determine the serial port. Otherwise, the configured serial port is
 298  * returned.
 299  *
 300  * Returns pointer to the currently selected serial port on success,
 301  * NULL on error.
 302  */
 303 static struct serial_device *get_current(void)
 304 {
 305         struct serial_device *dev;
 306
 307         if (!(gd->flags & GD_FLG_RELOC))
 308                 dev = default_serial_console();
 309         else if (!serial_current)
 310                 dev = default_serial_console();
 311         else
 312                 dev = serial_current;
 313
 314         /* We must have a console device */
 315         if (!dev) {
 316 #ifdef CONFIG_SPL_BUILD
 317                 puts("Cannot find console\n");
 318                 hang();
 319 #else
 320                 panic("Cannot find console\n");
 321 #endif
 322         }
 323
 324         return dev;
 325 }
 326
 327 /**
 328  * serial_init() - Initialize currently selected serial port
 329  *
 330  * This function initializes the currently selected serial port. This
 331  * usually involves setting up the registers of that particular port,
 332  * enabling clock and such. This function uses the get_current() call
 333  * to determine which port is selected.
 334  *
 335  * Returns 0 on success, negative on error.
 336  */
 337 int serial_init(void)
 338 {
 339         return get_current()->start();
 340 }
 341
 342 /**
 343  * serial_setbrg() - Configure baud-rate of currently selected serial port
 344  *
 345  * This function configures the baud-rate of the currently selected
 346  * serial port. The baud-rate is retrieved from global data within
 347  * the serial port driver. This function uses the get_current() call
 348  * to determine which port is selected.
 349  *
 350  * Returns 0 on success, negative on error.
 351  */
 352 void serial_setbrg(void)
 353 {
 354         get_current()->setbrg();
 355 }
 356
 357 /**
 358  * serial_getc() - Read character from currently selected serial port
 359  *
 360  * This function retrieves a character from currently selected serial
 361  * port. In case there is no character waiting on the serial port,
 362  * this function will block and wait for the character to appear. This
 363  * function uses the get_current() call to determine which port is
 364  * selected.
 365  *
 366  * Returns the character on success, negative on error.
 367  */
 368 int serial_getc(void)
 369 {
 370         return get_current()->getc();
 371 }
 372
 373 /**
 374  * serial_tstc() - Test if data is available on currently selected serial port
 375  *
 376  * This function tests if one or more characters are available on
 377  * currently selected serial port. This function never blocks. This
 378  * function uses the get_current() call to determine which port is
 379  * selected.
 380  *
 381  * Returns positive if character is available, zero otherwise.
 382  */
 383 int serial_tstc(void)
 384 {
 385         return get_current()->tstc();
 386 }
 387
 388 /**
 389  * serial_putc() - Output character via currently selected serial port
 390  * @c:  Single character to be output from the serial port.
 391  *
 392  * This function outputs a character via currently selected serial
 393  * port. This character is passed to the serial port driver responsible
 394  * for controlling the hardware. The hardware may still be in process
 395  * of transmitting another character, therefore this function may block
 396  * for a short amount of time. This function uses the get_current()
 397  * call to determine which port is selected.
 398  */
 399 void serial_putc(const char c)
 400 {
 401         get_current()->putc(c);
 402 }
 403
 404 /**
 405  * serial_puts() - Output string via currently selected serial port
 406  * @s:  Zero-terminated string to be output from the serial port.
 407  *
 408  * This function outputs a zero-terminated string via currently
 409  * selected serial port. This function behaves as an accelerator
 410  * in case the hardware can queue multiple characters for transfer.
 411  * The whole string that is to be output is available to the function
 412  * implementing the hardware manipulation. Transmitting the whole
 413  * string may take some time, thus this function may block for some
 414  * amount of time. This function uses the get_current() call to
 415  * determine which port is selected.
 416  */
 417 void serial_puts(const char *s)
 418 {
 419         get_current()->puts(s);
 420 }
 421
 422 /**
 423  * default_serial_puts() - Output string by calling serial_putc() in loop
 424  * @s:  Zero-terminated string to be output from the serial port.
 425  *
 426  * This function outputs a zero-terminated string by calling serial_putc()
 427  * in a loop. Most drivers do not support queueing more than one byte for
 428  * transfer, thus this function precisely implements their serial_puts().
 429  *
 430  * To optimize the number of get_current() calls, this function only
 431  * calls get_current() once and then directly accesses the putc() call
 432  * of the &struct serial_device .
 433  */
 434 void default_serial_puts(const char *s)
 435 {
 436         struct serial_device *dev = get_current();
 437         while (*s)
 438                 dev->putc(*s++);
 439 }
 440
 441 #if CONFIG_POST & CONFIG_SYS_POST_UART
 442 static const int bauds[] = CONFIG_SYS_BAUDRATE_TABLE;
 443
 444 /**
 445  * uart_post_test() - Test the currently selected serial port using POST
 446  * @flags:      POST framework flags
 447  *
 448  * Do a loopback test of the currently selected serial port. This
 449  * function is only useful in the context of the POST testing framwork.
 450  * The serial port is firstly configured into loopback mode and then
 451  * characters are sent through it.
 452  *
 453  * Returns 0 on success, value otherwise.
 454  */
 455 /* Mark weak until post/cpu/.../uart.c migrate over */
 456 __weak
 457 int uart_post_test(int flags)
 458 {
 459         unsigned char c;
 460         int ret, saved_baud, b;
 461         struct serial_device *saved_dev, *s;
 462         bd_t *bd = gd->bd;
 463
 464         /* Save current serial state */
 465         ret = 0;
 466         saved_dev = serial_current;
 467         saved_baud = bd->bi_baudrate;
 468
 469         for (s = serial_devices; s; s = s->next) {
 470                 /* If this driver doesn't support loop back, skip it */
 471                 if (!s->loop)
 472                         continue;
 473
 474                 /* Test the next device */
 475                 serial_current = s;
 476
 477                 ret = serial_init();
 478                 if (ret)
 479                         goto done;
 480
 481                 /* Consume anything that happens to be queued */
 482                 while (serial_tstc())
 483                         serial_getc();
 484
 485                 /* Enable loop back */
 486                 s->loop(1);
 487
 488                 /* Test every available baud rate */
 489                 for (b = 0; b < ARRAY_SIZE(bauds); ++b) {
 490                         bd->bi_baudrate = bauds[b];
 491                         serial_setbrg();
 492
 493                         /*
 494                          * Stick to printable chars to avoid issues:
 495                          *  - terminal corruption
 496                          *  - serial program reacting to sequences and sending
 497                          *    back random extra data
 498                          *  - most serial drivers add in extra chars (like \r\n)
 499                          */
 500                         for (c = 0x20; c < 0x7f; ++c) {
 501                                 /* Send it out */
 502                                 serial_putc(c);
 503
 504                                 /* Make sure it's the same one */
 505                                 ret = (c != serial_getc());
 506                                 if (ret) {
 507                                         s->loop(0);
 508                                         goto done;
 509                                 }
 510
 511                                 /* Clean up the output in case it was sent */
 512                                 serial_putc('\b');
 513                                 ret = ('\b' != serial_getc());
 514                                 if (ret) {
 515                                         s->loop(0);
 516                                         goto done;
 517                                 }
 518                         }
 519                 }
 520
 521                 /* Disable loop back */
 522                 s->loop(0);
 523
 524                 /* XXX: There is no serial_stop() !? */
 525                 if (s->stop)
 526                         s->stop();
 527         }
 528
 529  done:
 530         /* Restore previous serial state */
 531         serial_current = saved_dev;
 532         bd->bi_baudrate = saved_baud;
 533         serial_reinit_all();
 534         serial_setbrg();
 535
 536         return ret;
 537 }
 538 #endif