arch/cris/arch-v10/kernel/debugport.c

   1 /* Serialport functions for debugging
   2  *
   3  * Copyright (c) 2000-2007 Axis Communications AB
   4  *
   5  * Authors:  Bjorn Wesen
   6  *
   7  * Exports:
   8  *    console_print_etrax(char *buf)
   9  *    int getDebugChar()
  10  *    putDebugChar(int)
  11  *    enableDebugIRQ()
  12  *    init_etrax_debug()
  13  *
  14  */
  15
  16 #include <linux/console.h>
  17 #include <linux/init.h>
  18 #include <linux/major.h>
  19 #include <linux/delay.h>
  20 #include <linux/tty.h>
  21 #include <arch/svinto.h>
  22
  23 extern void reset_watchdog(void);
  24
  25 struct dbg_port
  26 {
  27   unsigned int index;
  28   const volatile unsigned* read;
  29   volatile char* write;
  30   volatile unsigned* xoff;
  31   volatile char* baud;
  32   volatile char* tr_ctrl;
  33   volatile char* rec_ctrl;
  34   unsigned long irq;
  35   unsigned int started;
  36   unsigned long baudrate;
  37   unsigned char parity;
  38   unsigned int bits;
  39 };
  40
  41 struct dbg_port ports[]=
  42 {
  43   {
  44     0,
  45     R_SERIAL0_READ,
  46     R_SERIAL0_TR_DATA,
  47     R_SERIAL0_XOFF,
  48     R_SERIAL0_BAUD,
  49     R_SERIAL0_TR_CTRL,
  50     R_SERIAL0_REC_CTRL,
  51     IO_STATE(R_IRQ_MASK1_SET, ser0_data, set),
  52     0,
  53     115200,
  54     'N',
  55     8
  56   },
  57   {
  58     1,
  59     R_SERIAL1_READ,
  60     R_SERIAL1_TR_DATA,
  61     R_SERIAL1_XOFF,
  62     R_SERIAL1_BAUD,
  63     R_SERIAL1_TR_CTRL,
  64     R_SERIAL1_REC_CTRL,
  65     IO_STATE(R_IRQ_MASK1_SET, ser1_data, set),
  66     0,
  67     115200,
  68     'N',
  69     8
  70   },
  71   {
  72     2,
  73     R_SERIAL2_READ,
  74     R_SERIAL2_TR_DATA,
  75     R_SERIAL2_XOFF,
  76     R_SERIAL2_BAUD,
  77     R_SERIAL2_TR_CTRL,
  78     R_SERIAL2_REC_CTRL,
  79     IO_STATE(R_IRQ_MASK1_SET, ser2_data, set),
  80     0,
  81     115200,
  82     'N',
  83     8
  84   },
  85   {
  86     3,
  87     R_SERIAL3_READ,
  88     R_SERIAL3_TR_DATA,
  89     R_SERIAL3_XOFF,
  90     R_SERIAL3_BAUD,
  91     R_SERIAL3_TR_CTRL,
  92     R_SERIAL3_REC_CTRL,
  93     IO_STATE(R_IRQ_MASK1_SET, ser3_data, set),
  94     0,
  95     115200,
  96     'N',
  97     8
  98   }
  99 };
 100
 101 #ifdef CONFIG_ETRAX_SERIAL
 102 extern struct tty_driver *serial_driver;
 103 #endif
 104
 105 struct dbg_port* port =
 106 #if defined(CONFIG_ETRAX_DEBUG_PORT0)
 107   &ports[0];
 108 #elif defined(CONFIG_ETRAX_DEBUG_PORT1)
 109   &ports[1];
 110 #elif defined(CONFIG_ETRAX_DEBUG_PORT2)
 111   &ports[2];
 112 #elif defined(CONFIG_ETRAX_DEBUG_PORT3)
 113   &ports[3];
 114 #else
 115   NULL;
 116 #endif
 117
 118 static struct dbg_port* kgdb_port =
 119 #if defined(CONFIG_ETRAX_KGDB_PORT0)
 120   &ports[0];
 121 #elif defined(CONFIG_ETRAX_KGDB_PORT1)
 122   &ports[1];
 123 #elif defined(CONFIG_ETRAX_KGDB_PORT2)
 124   &ports[2];
 125 #elif defined(CONFIG_ETRAX_KGDB_PORT3)
 126   &ports[3];
 127 #else
 128   NULL;
 129 #endif
 130
 131 static void
 132 start_port(struct dbg_port* p)
 133 {
 134         unsigned long rec_ctrl = 0;
 135         unsigned long tr_ctrl = 0;
 136
 137         if (!p)
 138                 return;
 139
 140         if (p->started)
 141                 return;
 142         p->started = 1;
 143
 144         if (p->index == 0)
 145         {
 146                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma6);
 147                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma6, unused);
 148         }
 149         else if (p->index == 1)
 150         {
 151                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma8);
 152                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma8, usb);
 153         }
 154         else if (p->index == 2)
 155         {
 156                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma2);
 157                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma2, par0);
 158                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma3);
 159                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma3, par0);
 160                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, ser2, select);
 161         }
 162         else
 163         {
 164                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma4);
 165                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma4, par1);
 166                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma5);
 167                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma5, par1);
 168                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, ser3, select);
 169         }
 170
 171         *R_GEN_CONFIG = genconfig_shadow;
 172
 173         *p->xoff =
 174                 IO_STATE(R_SERIAL0_XOFF, tx_stop, enable) |
 175                 IO_STATE(R_SERIAL0_XOFF, auto_xoff, disable) |
 176                 IO_FIELD(R_SERIAL0_XOFF, xoff_char, 0);
 177
 178         switch (p->baudrate)
 179         {
 180         case 0:
 181         case 115200:
 182                 *p->baud =
 183                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c115k2Hz) |
 184                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c115k2Hz);
 185                 break;
 186         case 1200:
 187                 *p->baud =
 188                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c1200Hz) |
 189                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c1200Hz);
 190                 break;
 191         case 2400:
 192                 *p->baud =
 193                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c2400Hz) |
 194                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c2400Hz);
 195                 break;
 196         case 4800:
 197                 *p->baud =
 198                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c4800Hz) |
 199                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c4800Hz);
 200                 break;
 201         case 9600:
 202                 *p->baud =
 203                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c9600Hz) |
 204                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c9600Hz);
 205                   break;
 206         case 19200:
 207                 *p->baud =
 208                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c19k2Hz) |
 209                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c19k2Hz);
 210                  break;
 211         case 38400:
 212                 *p->baud =
 213                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c38k4Hz) |
 214                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c38k4Hz);
 215                 break;
 216         case 57600:
 217                 *p->baud =
 218                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c57k6Hz) |
 219                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c57k6Hz);
 220                 break;
 221         default:
 222                 *p->baud =
 223                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c115k2Hz) |
 224                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c115k2Hz);
 225                   break;
 226         }
 227
 228         if (p->parity == 'E') {
 229                 rec_ctrl =
 230                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par, even) |
 231                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, enable);
 232                 tr_ctrl =
 233                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par, even) |
 234                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, enable);
 235         } else if (p->parity == 'O') {
 236                 rec_ctrl =
 237                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par, odd) |
 238                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, enable);
 239                 tr_ctrl =
 240                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par, odd) |
 241                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, enable);
 242         } else {
 243                 rec_ctrl =
 244                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par, even) |
 245                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, disable);
 246                 tr_ctrl =
 247                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par, even) |
 248                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, disable);
 249         }
 250         if (p->bits == 7)
 251         {
 252                 rec_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_bitnr, rec_7bit);
 253                 tr_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_bitnr, tr_7bit);
 254         }
 255         else
 256         {
 257                 rec_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_bitnr, rec_8bit);
 258                 tr_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_bitnr, tr_8bit);
 259         }
 260
 261         *p->rec_ctrl =
 262                 IO_STATE(R_SERIAL0_REC_CTRL, dma_err, stop) |
 263                 IO_STATE(R_SERIAL0_REC_CTRL, rec_enable, enable) |
 264                 IO_STATE(R_SERIAL0_REC_CTRL, rts_, active) |
 265                 IO_STATE(R_SERIAL0_REC_CTRL, sampling, middle) |
 266                 IO_STATE(R_SERIAL0_REC_CTRL, rec_stick_par, normal) |
 267                 rec_ctrl;
 268
 269         *p->tr_ctrl =
 270                 IO_FIELD(R_SERIAL0_TR_CTRL, txd, 0) |
 271                 IO_STATE(R_SERIAL0_TR_CTRL, tr_enable, enable) |
 272                 IO_STATE(R_SERIAL0_TR_CTRL, auto_cts, disabled) |
 273                 IO_STATE(R_SERIAL0_TR_CTRL, stop_bits, one_bit) |
 274                 IO_STATE(R_SERIAL0_TR_CTRL, tr_stick_par, normal) |
 275                 tr_ctrl;
 276 }
 277
 278 static void
 279 console_write_direct(struct console *co, const char *buf, unsigned int len)
 280 {
 281         int i;
 282         unsigned long flags;
 283
 284         if (!port)
 285                 return;
 286
 287         local_irq_save(flags);
 288
 289         /* Send data */
 290         for (i = 0; i < len; i++) {
 291                 /* LF -> CRLF */
 292                 if (buf[i] == '\n') {
 293                         while (!(*port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
 294                         ;
 295                         *port->write = '\r';
 296                 }
 297                 /* Wait until transmitter is ready and send.*/
 298                 while (!(*port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
 299                         ;
 300                 *port->write = buf[i];
 301         }
 302
 303         /*
 304          * Feed the watchdog, otherwise it will reset the chip during boot.
 305          * The time to send an ordinary boot message line (10-90 chars)
 306          * varies between 1-8ms at 115200. What makes up for the additional
 307          * 90ms that allows the watchdog to bite?
 308         */
 309         reset_watchdog();
 310
 311         local_irq_restore(flags);
 312 }
 313
 314 static void
 315 console_write(struct console *co, const char *buf, unsigned int len)
 316 {
 317         if (!port)
 318                 return;
 319
 320         console_write_direct(co, buf, len);
 321 }
 322
 323 /* legacy function */
 324
 325 void
 326 console_print_etrax(const char *buf)
 327 {
 328         console_write(NULL, buf, strlen(buf));
 329 }
 330
 331 /* Use polling to get a single character FROM the debug port */
 332
 333 int
 334 getDebugChar(void)
 335 {
 336         unsigned long readval;
 337
 338         if (!kgdb_port)
 339                 return 0;
 340
 341         do {
 342                 readval = *kgdb_port->read;
 343         } while (!(readval & IO_MASK(R_SERIAL0_READ, data_avail)));
 344
 345         return (readval & IO_MASK(R_SERIAL0_READ, data_in));
 346 }
 347
 348 /* Use polling to put a single character to the debug port */
 349
 350 void
 351 putDebugChar(int val)
 352 {
 353         if (!kgdb_port)
 354                 return;
 355
 356         while (!(*kgdb_port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
 357                 ;
 358         *kgdb_port->write = val;
 359 }
 360
 361 /* Enable irq for receiving chars on the debug port, used by kgdb */
 362
 363 void
 364 enableDebugIRQ(void)
 365 {
 366         if (!kgdb_port)
 367                 return;
 368
 369         *R_IRQ_MASK1_SET = kgdb_port->irq;
 370         /* use R_VECT_MASK directly, since we really bypass Linux normal
 371          * IRQ handling in kgdb anyway, we don't need to use enable_irq
 372          */
 373         *R_VECT_MASK_SET = IO_STATE(R_VECT_MASK_SET, serial, set);
 374
 375         *kgdb_port->rec_ctrl = IO_STATE(R_SERIAL0_REC_CTRL, rec_enable, enable);
 376 }
 377
 378 static int __init
 379 console_setup(struct console *co, char *options)
 380 {
 381         char* s;
 382
 383         if (options) {
 384                 port = &ports[co->index];
 385                 port->baudrate = 115200;
 386                 port->parity = 'N';
 387                 port->bits = 8;
 388                 port->baudrate = simple_strtoul(options, NULL, 10);
 389                 s = options;
 390                 while(*s >= '0' && *s <= '9')
 391                         s++;
 392                 if (*s) port->parity = *s++;
 393                 if (*s) port->bits   = *s++ - '0';
 394                 port->started = 0;
 395                 start_port(0);
 396         }
 397         return 0;
 398 }
 399
 400
 401 /* This is a dummy serial device that throws away anything written to it.
 402  * This is used when no debug output is wanted.
 403  */
 404 static struct tty_driver dummy_driver;
 405
 406 static int dummy_open(struct tty_struct *tty, struct file * filp)
 407 {
 408         return 0;
 409 }
 410
 411 static void dummy_close(struct tty_struct *tty, struct file * filp)
 412 {
 413 }
 414
 415 static int dummy_write(struct tty_struct * tty,
 416                        const unsigned char *buf, int count)
 417 {
 418         return count;
 419 }
 420
 421 static int dummy_write_room(struct tty_struct *tty)
 422 {
 423         return 8192;
 424 }
 425
 426 static const struct tty_operations dummy_ops = {
 427         .open = dummy_open,
 428         .close = dummy_close,
 429         .write = dummy_write,
 430         .write_room = dummy_write_room,
 431 };
 432
 433 void __init
 434 init_dummy_console(void)
 435 {
 436         memset(&dummy_driver, 0, sizeof(struct tty_driver));
 437         dummy_driver.driver_name = "serial";
 438         dummy_driver.name = "ttyS";
 439         dummy_driver.major = TTY_MAJOR;
 440         dummy_driver.minor_start = 68;
 441         dummy_driver.num = 1;       /* etrax100 has 4 serial ports */
 442         dummy_driver.type = TTY_DRIVER_TYPE_SERIAL;
 443         dummy_driver.subtype = SERIAL_TYPE_NORMAL;
 444         dummy_driver.init_termios = tty_std_termios;
 445         /* Normally B9600 default... */
 446         dummy_driver.init_termios.c_cflag =
 447                 B115200 | CS8 | CREAD | HUPCL | CLOCAL;
 448         dummy_driver.flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
 449         dummy_driver.init_termios.c_ispeed = 115200;
 450         dummy_driver.init_termios.c_ospeed = 115200;
 451
 452         dummy_driver.ops = &dummy_ops;
 453         if (tty_register_driver(&dummy_driver))
 454                 panic("Couldn't register dummy serial driver\n");
 455 }
 456
 457 static struct tty_driver*
 458 etrax_console_device(struct console* co, int *index)
 459 {
 460         if (port)
 461                 *index = port->index;
 462         else
 463                 *index = 0;
 464 #ifdef CONFIG_ETRAX_SERIAL
 465         return port ? serial_driver : &dummy_driver;
 466 #else
 467         return &dummy_driver;
 468 #endif
 469 }
 470
 471 static struct console ser_console = {
 472         name : "ttyS",
 473         write: console_write,
 474         read : NULL,
 475         device : etrax_console_device,
 476         unblank : NULL,
 477         setup : console_setup,
 478         flags : CON_PRINTBUFFER,
 479         index : -1,
 480         cflag : 0,
 481         next : NULL
 482 };
 483 static struct console ser0_console = {
 484         name : "ttyS",
 485         write: console_write,
 486         read : NULL,
 487         device : etrax_console_device,
 488         unblank : NULL,
 489         setup : console_setup,
 490         flags : CON_PRINTBUFFER,
 491         index : 0,
 492         cflag : 0,
 493         next : NULL
 494 };
 495
 496 static struct console ser1_console = {
 497         name : "ttyS",
 498         write: console_write,
 499         read : NULL,
 500         device : etrax_console_device,
 501         unblank : NULL,
 502         setup : console_setup,
 503         flags : CON_PRINTBUFFER,
 504         index : 1,
 505         cflag : 0,
 506         next : NULL
 507 };
 508 static struct console ser2_console = {
 509         name : "ttyS",
 510         write: console_write,
 511         read : NULL,
 512         device : etrax_console_device,
 513         unblank : NULL,
 514         setup : console_setup,
 515         flags : CON_PRINTBUFFER,
 516         index : 2,
 517         cflag : 0,
 518         next : NULL
 519 };
 520 static struct console ser3_console = {
 521         name : "ttyS",
 522         write: console_write,
 523         read : NULL,
 524         device : etrax_console_device,
 525         unblank : NULL,
 526         setup : console_setup,
 527         flags : CON_PRINTBUFFER,
 528         index : 3,
 529         cflag : 0,
 530         next : NULL
 531 };
 532 /*
 533  *      Register console (for printk's etc)
 534  */
 535
 536 int __init
 537 init_etrax_debug(void)
 538 {
 539         static int first = 1;
 540
 541         if (!first) {
 542                 unregister_console(&ser_console);
 543                 register_console(&ser0_console);
 544                 register_console(&ser1_console);
 545                 register_console(&ser2_console);
 546                 register_console(&ser3_console);
 547                 init_dummy_console();
 548                 return 0;
 549         }
 550
 551         first = 0;
 552         register_console(&ser_console);
 553         start_port(port);
 554 #ifdef CONFIG_ETRAX_KGDB
 555         start_port(kgdb_port);
 556 #endif
 557         return 0;
 558 }
 559 __initcall(init_etrax_debug);