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 <asm/system.h>
  22 #include <asm/arch/svinto.h>
  23 #include <asm/io.h>             /* Get SIMCOUT. */
  24
  25 extern void reset_watchdog(void);
  26
  27 struct dbg_port
  28 {
  29   unsigned int index;
  30   const volatile unsigned* read;
  31   volatile char* write;
  32   volatile unsigned* xoff;
  33   volatile char* baud;
  34   volatile char* tr_ctrl;
  35   volatile char* rec_ctrl;
  36   unsigned long irq;
  37   unsigned int started;
  38   unsigned long baudrate;
  39   unsigned char parity;
  40   unsigned int bits;
  41 };
  42
  43 struct dbg_port ports[]=
  44 {
  45   {
  46     0,
  47     R_SERIAL0_READ,
  48     R_SERIAL0_TR_DATA,
  49     R_SERIAL0_XOFF,
  50     R_SERIAL0_BAUD,
  51     R_SERIAL0_TR_CTRL,
  52     R_SERIAL0_REC_CTRL,
  53     IO_STATE(R_IRQ_MASK1_SET, ser0_data, set),
  54     0,
  55     115200,
  56     'N',
  57     8
  58   },
  59   {
  60     1,
  61     R_SERIAL1_READ,
  62     R_SERIAL1_TR_DATA,
  63     R_SERIAL1_XOFF,
  64     R_SERIAL1_BAUD,
  65     R_SERIAL1_TR_CTRL,
  66     R_SERIAL1_REC_CTRL,
  67     IO_STATE(R_IRQ_MASK1_SET, ser1_data, set),
  68     0,
  69     115200,
  70     'N',
  71     8
  72   },
  73   {
  74     2,
  75     R_SERIAL2_READ,
  76     R_SERIAL2_TR_DATA,
  77     R_SERIAL2_XOFF,
  78     R_SERIAL2_BAUD,
  79     R_SERIAL2_TR_CTRL,
  80     R_SERIAL2_REC_CTRL,
  81     IO_STATE(R_IRQ_MASK1_SET, ser2_data, set),
  82     0,
  83     115200,
  84     'N',
  85     8
  86   },
  87   {
  88     3,
  89     R_SERIAL3_READ,
  90     R_SERIAL3_TR_DATA,
  91     R_SERIAL3_XOFF,
  92     R_SERIAL3_BAUD,
  93     R_SERIAL3_TR_CTRL,
  94     R_SERIAL3_REC_CTRL,
  95     IO_STATE(R_IRQ_MASK1_SET, ser3_data, set),
  96     0,
  97     115200,
  98     'N',
  99     8
 100   }
 101 };
 102
 103 #ifdef CONFIG_ETRAX_SERIAL
 104 extern struct tty_driver *serial_driver;
 105 #endif
 106
 107 struct dbg_port* port =
 108 #if defined(CONFIG_ETRAX_DEBUG_PORT0)
 109   &ports[0];
 110 #elif defined(CONFIG_ETRAX_DEBUG_PORT1)
 111   &ports[1];
 112 #elif defined(CONFIG_ETRAX_DEBUG_PORT2)
 113   &ports[2];
 114 #elif defined(CONFIG_ETRAX_DEBUG_PORT3)
 115   &ports[3];
 116 #else
 117   NULL;
 118 #endif
 119
 120 static struct dbg_port* kgdb_port =
 121 #if defined(CONFIG_ETRAX_KGDB_PORT0)
 122   &ports[0];
 123 #elif defined(CONFIG_ETRAX_KGDB_PORT1)
 124   &ports[1];
 125 #elif defined(CONFIG_ETRAX_KGDB_PORT2)
 126   &ports[2];
 127 #elif defined(CONFIG_ETRAX_KGDB_PORT3)
 128   &ports[3];
 129 #else
 130   NULL;
 131 #endif
 132
 133 static void
 134 start_port(struct dbg_port* p)
 135 {
 136         unsigned long rec_ctrl = 0;
 137         unsigned long tr_ctrl = 0;
 138
 139         if (!p)
 140                 return;
 141
 142         if (p->started)
 143                 return;
 144         p->started = 1;
 145
 146         if (p->index == 0)
 147         {
 148                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma6);
 149                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma6, unused);
 150         }
 151         else if (p->index == 1)
 152         {
 153                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma8);
 154                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma8, usb);
 155         }
 156         else if (p->index == 2)
 157         {
 158                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma2);
 159                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma2, par0);
 160                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma3);
 161                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma3, par0);
 162                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, ser2, select);
 163         }
 164         else
 165         {
 166                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma4);
 167                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma4, par1);
 168                 genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma5);
 169                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma5, par1);
 170                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, ser3, select);
 171         }
 172
 173         *R_GEN_CONFIG = genconfig_shadow;
 174
 175         *p->xoff =
 176                 IO_STATE(R_SERIAL0_XOFF, tx_stop, enable) |
 177                 IO_STATE(R_SERIAL0_XOFF, auto_xoff, disable) |
 178                 IO_FIELD(R_SERIAL0_XOFF, xoff_char, 0);
 179
 180         switch (p->baudrate)
 181         {
 182         case 0:
 183         case 115200:
 184                 *p->baud =
 185                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c115k2Hz) |
 186                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c115k2Hz);
 187                 break;
 188         case 1200:
 189                 *p->baud =
 190                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c1200Hz) |
 191                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c1200Hz);
 192                 break;
 193         case 2400:
 194                 *p->baud =
 195                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c2400Hz) |
 196                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c2400Hz);
 197                 break;
 198         case 4800:
 199                 *p->baud =
 200                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c4800Hz) |
 201                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c4800Hz);
 202                 break;
 203         case 9600:
 204                 *p->baud =
 205                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c9600Hz) |
 206                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c9600Hz);
 207                   break;
 208         case 19200:
 209                 *p->baud =
 210                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c19k2Hz) |
 211                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c19k2Hz);
 212                  break;
 213         case 38400:
 214                 *p->baud =
 215                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c38k4Hz) |
 216                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c38k4Hz);
 217                 break;
 218         case 57600:
 219                 *p->baud =
 220                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c57k6Hz) |
 221                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c57k6Hz);
 222                 break;
 223         default:
 224                 *p->baud =
 225                   IO_STATE(R_SERIAL0_BAUD, tr_baud, c115k2Hz) |
 226                   IO_STATE(R_SERIAL0_BAUD, rec_baud, c115k2Hz);
 227                   break;
 228         }
 229
 230         if (p->parity == 'E') {
 231                 rec_ctrl =
 232                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par, even) |
 233                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, enable);
 234                 tr_ctrl =
 235                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par, even) |
 236                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, enable);
 237         } else if (p->parity == 'O') {
 238                 rec_ctrl =
 239                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par, odd) |
 240                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, enable);
 241                 tr_ctrl =
 242                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par, odd) |
 243                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, enable);
 244         } else {
 245                 rec_ctrl =
 246                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par, even) |
 247                   IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, disable);
 248                 tr_ctrl =
 249                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par, even) |
 250                   IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, disable);
 251         }
 252         if (p->bits == 7)
 253         {
 254                 rec_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_bitnr, rec_7bit);
 255                 tr_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_bitnr, tr_7bit);
 256         }
 257         else
 258         {
 259                 rec_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_bitnr, rec_8bit);
 260                 tr_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_bitnr, tr_8bit);
 261         }
 262
 263         *p->rec_ctrl =
 264                 IO_STATE(R_SERIAL0_REC_CTRL, dma_err, stop) |
 265                 IO_STATE(R_SERIAL0_REC_CTRL, rec_enable, enable) |
 266                 IO_STATE(R_SERIAL0_REC_CTRL, rts_, active) |
 267                 IO_STATE(R_SERIAL0_REC_CTRL, sampling, middle) |
 268                 IO_STATE(R_SERIAL0_REC_CTRL, rec_stick_par, normal) |
 269                 rec_ctrl;
 270
 271         *p->tr_ctrl =
 272                 IO_FIELD(R_SERIAL0_TR_CTRL, txd, 0) |
 273                 IO_STATE(R_SERIAL0_TR_CTRL, tr_enable, enable) |
 274                 IO_STATE(R_SERIAL0_TR_CTRL, auto_cts, disabled) |
 275                 IO_STATE(R_SERIAL0_TR_CTRL, stop_bits, one_bit) |
 276                 IO_STATE(R_SERIAL0_TR_CTRL, tr_stick_par, normal) |
 277                 tr_ctrl;
 278 }
 279
 280 static void
 281 console_write_direct(struct console *co, const char *buf, unsigned int len)
 282 {
 283         int i;
 284         unsigned long flags;
 285
 286         if (!port)
 287                 return;
 288
 289         local_irq_save(flags);
 290
 291         /* Send data */
 292         for (i = 0; i < len; i++) {
 293                 /* LF -> CRLF */
 294                 if (buf[i] == '\n') {
 295                         while (!(*port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
 296                         ;
 297                         *port->write = '\r';
 298                 }
 299                 /* Wait until transmitter is ready and send.*/
 300                 while (!(*port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
 301                         ;
 302                 *port->write = buf[i];
 303         }
 304
 305         /*
 306          * Feed the watchdog, otherwise it will reset the chip during boot.
 307          * The time to send an ordinary boot message line (10-90 chars)
 308          * varies between 1-8ms at 115200. What makes up for the additional
 309          * 90ms that allows the watchdog to bite?
 310         */
 311         reset_watchdog();
 312
 313         local_irq_restore(flags);
 314 }
 315
 316 static void
 317 console_write(struct console *co, const char *buf, unsigned int len)
 318 {
 319         if (!port)
 320                 return;
 321
 322 #ifdef CONFIG_SVINTO_SIM
 323         /* no use to simulate the serial debug output */
 324         SIMCOUT(buf, len);
 325         return;
 326 #endif
 327
 328         console_write_direct(co, buf, len);
 329 }
 330
 331 /* legacy function */
 332
 333 void
 334 console_print_etrax(const char *buf)
 335 {
 336         console_write(NULL, buf, strlen(buf));
 337 }
 338
 339 /* Use polling to get a single character FROM the debug port */
 340
 341 int
 342 getDebugChar(void)
 343 {
 344         unsigned long readval;
 345
 346         if (!kgdb_port)
 347                 return 0;
 348
 349         do {
 350                 readval = *kgdb_port->read;
 351         } while (!(readval & IO_MASK(R_SERIAL0_READ, data_avail)));
 352
 353         return (readval & IO_MASK(R_SERIAL0_READ, data_in));
 354 }
 355
 356 /* Use polling to put a single character to the debug port */
 357
 358 void
 359 putDebugChar(int val)
 360 {
 361         if (!kgdb_port)
 362                 return;
 363
 364         while (!(*kgdb_port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
 365                 ;
 366         *kgdb_port->write = val;
 367 }
 368
 369 /* Enable irq for receiving chars on the debug port, used by kgdb */
 370
 371 void
 372 enableDebugIRQ(void)
 373 {
 374         if (!kgdb_port)
 375                 return;
 376
 377         *R_IRQ_MASK1_SET = kgdb_port->irq;
 378         /* use R_VECT_MASK directly, since we really bypass Linux normal
 379          * IRQ handling in kgdb anyway, we don't need to use enable_irq
 380          */
 381         *R_VECT_MASK_SET = IO_STATE(R_VECT_MASK_SET, serial, set);
 382
 383         *kgdb_port->rec_ctrl = IO_STATE(R_SERIAL0_REC_CTRL, rec_enable, enable);
 384 }
 385
 386 static int __init
 387 console_setup(struct console *co, char *options)
 388 {
 389         char* s;
 390
 391         if (options) {
 392                 port = &ports[co->index];
 393                 port->baudrate = 115200;
 394                 port->parity = 'N';
 395                 port->bits = 8;
 396                 port->baudrate = simple_strtoul(options, NULL, 10);
 397                 s = options;
 398                 while(*s >= '0' && *s <= '9')
 399                         s++;
 400                 if (*s) port->parity = *s++;
 401                 if (*s) port->bits   = *s++ - '0';
 402                 port->started = 0;
 403                 start_port(0);
 404         }
 405         return 0;
 406 }
 407
 408
 409 /* This is a dummy serial device that throws away anything written to it.
 410  * This is used when no debug output is wanted.
 411  */
 412 static struct tty_driver dummy_driver;
 413
 414 static int dummy_open(struct tty_struct *tty, struct file * filp)
 415 {
 416         return 0;
 417 }
 418
 419 static void dummy_close(struct tty_struct *tty, struct file * filp)
 420 {
 421 }
 422
 423 static int dummy_write(struct tty_struct * tty,
 424                        const unsigned char *buf, int count)
 425 {
 426         return count;
 427 }
 428
 429 static int
 430 dummy_write_room(struct tty_struct *tty)
 431 {
 432         return 8192;
 433 }
 434
 435 void __init
 436 init_dummy_console(void)
 437 {
 438         memset(&dummy_driver, 0, sizeof(struct tty_driver));
 439         dummy_driver.driver_name = "serial";
 440         dummy_driver.name = "ttyS";
 441         dummy_driver.major = TTY_MAJOR;
 442         dummy_driver.minor_start = 68;
 443         dummy_driver.num = 1;       /* etrax100 has 4 serial ports */
 444         dummy_driver.type = TTY_DRIVER_TYPE_SERIAL;
 445         dummy_driver.subtype = SERIAL_TYPE_NORMAL;
 446         dummy_driver.init_termios = tty_std_termios;
 447         dummy_driver.init_termios.c_cflag =
 448                 B115200 | CS8 | CREAD | HUPCL | CLOCAL; /* is normally B9600 default... */
 449         dummy_driver.flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
 450
 451         dummy_driver.open = dummy_open;
 452         dummy_driver.close = dummy_close;
 453         dummy_driver.write = dummy_write;
 454         dummy_driver.write_room = dummy_write_room;
 455         if (tty_register_driver(&dummy_driver))
 456                 panic("Couldn't register dummy serial driver\n");
 457 }
 458
 459 static struct tty_driver*
 460 etrax_console_device(struct console* co, int *index)
 461 {
 462         if (port)
 463                 *index = port->index;
 464         else
 465                 *index = 0;
 466 #ifdef CONFIG_ETRAX_SERIAL
 467         return port ? serial_driver : &dummy_driver;
 468 #else
 469         return &dummy_driver;
 470 #endif
 471 }
 472
 473 static struct console sercons = {
 474         name : "ttyS",
 475         write: console_write,
 476         read : NULL,
 477         device : etrax_console_device,
 478         unblank : NULL,
 479         setup : console_setup,
 480         flags : CON_PRINTBUFFER,
 481         index : -1,
 482         cflag : 0,
 483         next : NULL
 484 };
 485 static struct console sercons0 = {
 486         name : "ttyS",
 487         write: console_write,
 488         read : NULL,
 489         device : etrax_console_device,
 490         unblank : NULL,
 491         setup : console_setup,
 492         flags : CON_PRINTBUFFER,
 493         index : 0,
 494         cflag : 0,
 495         next : NULL
 496 };
 497
 498 static struct console sercons1 = {
 499         name : "ttyS",
 500         write: console_write,
 501         read : NULL,
 502         device : etrax_console_device,
 503         unblank : NULL,
 504         setup : console_setup,
 505         flags : CON_PRINTBUFFER,
 506         index : 1,
 507         cflag : 0,
 508         next : NULL
 509 };
 510 static struct console sercons2 = {
 511         name : "ttyS",
 512         write: console_write,
 513         read : NULL,
 514         device : etrax_console_device,
 515         unblank : NULL,
 516         setup : console_setup,
 517         flags : CON_PRINTBUFFER,
 518         index : 2,
 519         cflag : 0,
 520         next : NULL
 521 };
 522 static struct console sercons3 = {
 523         name : "ttyS",
 524         write: console_write,
 525         read : NULL,
 526         device : etrax_console_device,
 527         unblank : NULL,
 528         setup : console_setup,
 529         flags : CON_PRINTBUFFER,
 530         index : 3,
 531         cflag : 0,
 532         next : NULL
 533 };
 534 /*
 535  *      Register console (for printk's etc)
 536  */
 537
 538 int __init
 539 init_etrax_debug(void)
 540 {
 541         static int first = 1;
 542
 543         if (!first) {
 544                 unregister_console(&sercons);
 545                 register_console(&sercons0);
 546                 register_console(&sercons1);
 547                 register_console(&sercons2);
 548                 register_console(&sercons3);
 549                 init_dummy_console();
 550                 return 0;
 551         }
 552
 553         first = 0;
 554         register_console(&sercons);
 555         start_port(port);
 556 #ifdef CONFIG_ETRAX_KGDB
 557         start_port(kgdb_port);
 558 #endif
 559         return 0;
 560 }
 561 __initcall(init_etrax_debug);