gdb/ser-go32.c

   1 /* Remote serial interface for local (hardwired) serial ports for GO32.
   2    Copyright 1992, 1993, 2000 Free Software Foundation, Inc.
   3
   4    Contributed by Nigel Stephens, Algorithmics Ltd. (nigel@algor.co.uk).
   5
   6    This version uses DPMI interrupts to handle buffered i/o
   7    without the separate "asynctsr" program.
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 2 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program; if not, write to the Free Software
  23    Foundation, Inc., 59 Temple Place - Suite 330,
  24    Boston, MA 02111-1307, USA.  */
  25
  26 #include "defs.h"
  27 #include "gdbcmd.h"
  28 #include "serial.h"
  29
  30
  31 /*
  32  * NS16550 UART registers
  33  */
  34
  35 #define COM1ADDR        0x3f8
  36 #define COM2ADDR        0x2f8
  37 #define COM3ADDR        0x3e8
  38 #define COM4ADDR        0x3e0
  39
  40 #define com_data        0       /* data register (R/W) */
  41 #define com_dlbl        0       /* divisor latch low (W) */
  42 #define com_ier         1       /* interrupt enable (W) */
  43 #define com_dlbh        1       /* divisor latch high (W) */
  44 #define com_iir         2       /* interrupt identification (R) */
  45 #define com_fifo        2       /* FIFO control (W) */
  46 #define com_lctl        3       /* line control register (R/W) */
  47 #define com_cfcr        3       /* line control register (R/W) */
  48 #define com_mcr         4       /* modem control register (R/W) */
  49 #define com_lsr         5       /* line status register (R/W) */
  50 #define com_msr         6       /* modem status register (R/W) */
  51
  52 /*
  53  * Constants for computing 16 bit baud rate divisor (lower byte
  54  * in com_dlbl, upper in com_dlbh) from 1.8432MHz crystal.  Divisor is
  55  * 1.8432 MHz / (16 * X) for X bps.  If the baud rate can't be set
  56  * to within +- (desired_rate*SPEED_TOLERANCE/1000) bps, we fail.
  57  */
  58 #define COMTICK         (1843200/16)
  59 #define SPEED_TOLERANCE 30      /* thousandths; real == desired +- 3.0% */
  60
  61 /* interrupt enable register */
  62 #define IER_ERXRDY      0x1     /* int on rx ready */
  63 #define IER_ETXRDY      0x2     /* int on tx ready */
  64 #define IER_ERLS        0x4     /* int on line status change */
  65 #define IER_EMSC        0x8     /* int on modem status change */
  66
  67 /* interrupt identification register */
  68 #define IIR_FIFO_MASK   0xc0    /* set if FIFOs are enabled */
  69 #define IIR_IMASK       0xf     /* interrupt cause mask */
  70 #define IIR_NOPEND      0x1     /* nothing pending */
  71 #define IIR_RLS         0x6     /* receive line status */
  72 #define IIR_RXRDY       0x4     /* receive ready */
  73 #define IIR_RXTOUT      0xc     /* receive timeout */
  74 #define IIR_TXRDY       0x2     /* transmit ready */
  75 #define IIR_MLSC        0x0     /* modem status */
  76
  77
  78 /* fifo control register */
  79 #define FIFO_ENABLE     0x01    /* enable fifo */
  80 #define FIFO_RCV_RST    0x02    /* reset receive fifo */
  81 #define FIFO_XMT_RST    0x04    /* reset transmit fifo */
  82 #define FIFO_DMA_MODE   0x08    /* enable dma mode */
  83 #define FIFO_TRIGGER_1  0x00    /* trigger at 1 char */
  84 #define FIFO_TRIGGER_4  0x40    /* trigger at 4 chars */
  85 #define FIFO_TRIGGER_8  0x80    /* trigger at 8 chars */
  86 #define FIFO_TRIGGER_14 0xc0    /* trigger at 14 chars */
  87
  88 /* character format control register */
  89 #define CFCR_DLAB       0x80    /* divisor latch */
  90 #define CFCR_SBREAK     0x40    /* send break */
  91 #define CFCR_PZERO      0x30    /* zero parity */
  92 #define CFCR_PONE       0x20    /* one parity */
  93 #define CFCR_PEVEN      0x10    /* even parity */
  94 #define CFCR_PODD       0x00    /* odd parity */
  95 #define CFCR_PENAB      0x08    /* parity enable */
  96 #define CFCR_STOPB      0x04    /* 2 stop bits */
  97 #define CFCR_8BITS      0x03    /* 8 data bits */
  98 #define CFCR_7BITS      0x02    /* 7 data bits */
  99 #define CFCR_6BITS      0x01    /* 6 data bits */
 100 #define CFCR_5BITS      0x00    /* 5 data bits */
 101
 102 /* modem control register */
 103 #define MCR_LOOPBACK    0x10    /* loopback */
 104 #define MCR_IENABLE     0x08    /* output 2 = int enable */
 105 #define MCR_DRS         0x04    /* output 1 = xxx */
 106 #define MCR_RTS         0x02    /* enable RTS */
 107 #define MCR_DTR         0x01    /* enable DTR */
 108
 109 /* line status register */
 110 #define LSR_RCV_FIFO    0x80    /* error in receive fifo */
 111 #define LSR_TSRE        0x40    /* transmitter empty */
 112 #define LSR_TXRDY       0x20    /* transmitter ready */
 113 #define LSR_BI          0x10    /* break detected */
 114 #define LSR_FE          0x08    /* framing error */
 115 #define LSR_PE          0x04    /* parity error */
 116 #define LSR_OE          0x02    /* overrun error */
 117 #define LSR_RXRDY       0x01    /* receiver ready */
 118 #define LSR_RCV_MASK    0x1f
 119
 120 /* modem status register */
 121 #define MSR_DCD         0x80
 122 #define MSR_RI          0x40
 123 #define MSR_DSR         0x20
 124 #define MSR_CTS         0x10
 125 #define MSR_DDCD        0x08
 126 #define MSR_TERI        0x04
 127 #define MSR_DDSR        0x02
 128 #define MSR_DCTS        0x01
 129
 130 #include <string.h>
 131 #include <dos.h>
 132 #include <go32.h>
 133 #include <dpmi.h>
 134 typedef unsigned long u_long;
 135
 136 /* 16550 rx fifo trigger point */
 137 #define FIFO_TRIGGER    FIFO_TRIGGER_4
 138
 139 /* input buffer size */
 140 #define CBSIZE  4096
 141
 142 /* return raw 18Hz clock count */
 143 extern long rawclock (void);
 144
 145 #define RAWHZ   18
 146
 147 #ifdef DOS_STATS
 148 #define CNT_RX          16
 149 #define CNT_TX          17
 150 #define CNT_STRAY       18
 151 #define CNT_ORUN        19
 152 #define NCNT            20
 153
 154 static int intrcnt;
 155 static int cnts[NCNT];
 156 static char *cntnames[NCNT] =
 157 {
 158   /* h/w interrupt counts. */
 159   "mlsc", "nopend", "txrdy", "?3",
 160   "rxrdy", "?5", "rls", "?7",
 161   "?8", "?9", "?a", "?b",
 162   "rxtout", "?d", "?e", "?f",
 163   /* s/w counts. */
 164   "rxcnt", "txcnt", "stray", "swoflo"
 165 };
 166
 167 #define COUNT(x) cnts[x]++
 168 #else
 169 #define COUNT(x)
 170 #endif
 171
 172 /* Main interrupt controller port addresses. */
 173 #define ICU_BASE        0x20
 174 #define ICU_OCW2        (ICU_BASE + 0)
 175 #define ICU_MASK        (ICU_BASE + 1)
 176
 177 /* Original interrupt controller mask register. */
 178 unsigned char icu_oldmask;
 179
 180 /* Maximum of 8 interrupts (we don't handle the slave icu yet). */
 181 #define NINTR   8
 182
 183 static struct intrupt
 184   {
 185     char inuse;
 186     struct dos_ttystate *port;
 187     _go32_dpmi_seginfo old_rmhandler;
 188     _go32_dpmi_seginfo old_pmhandler;
 189     _go32_dpmi_seginfo new_rmhandler;
 190     _go32_dpmi_seginfo new_pmhandler;
 191     _go32_dpmi_registers regs;
 192   }
 193 intrupts[NINTR];
 194
 195
 196 static struct dos_ttystate
 197   {
 198     int base;
 199     int irq;
 200     int refcnt;
 201     struct intrupt *intrupt;
 202     int fifo;
 203     int baudrate;
 204     unsigned char cbuf[CBSIZE];
 205     unsigned int first;
 206     unsigned int count;
 207     int txbusy;
 208     unsigned char old_mcr;
 209     int ferr;
 210     int perr;
 211     int oflo;
 212     int msr;
 213   }
 214 ports[4] =
 215 {
 216   {
 217     COM1ADDR, 4, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
 218   }
 219   ,
 220   {
 221     COM2ADDR, 3, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
 222   }
 223   ,
 224   {
 225     COM3ADDR, 4, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
 226   }
 227   ,
 228   {
 229     COM4ADDR, 3, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
 230   }
 231 };
 232
 233 static int dos_open (serial_t scb, const char *name);
 234 static void dos_raw (serial_t scb);
 235 static int dos_readchar (serial_t scb, int timeout);
 236 static int dos_setbaudrate (serial_t scb, int rate);
 237 static int dos_write (serial_t scb, const char *str, int len);
 238 static void dos_close (serial_t scb);
 239 static serial_ttystate dos_get_tty_state (serial_t scb);
 240 static int dos_set_tty_state (serial_t scb, serial_ttystate state);
 241 static int dos_baudconv (int rate);
 242
 243 #define inb(p,a)        inportb((p)->base + (a))
 244 #define outb(p,a,v)     outportb((p)->base + (a), (v))
 245 #define disable()       asm volatile ("cli");
 246 #define enable()        asm volatile ("sti");
 247
 248
 249 static int
 250 dos_getc (volatile struct dos_ttystate *port)
 251 {
 252   int c;
 253
 254   if (port->count == 0)
 255     return -1;
 256
 257   c = port->cbuf[port->first];
 258   disable ();
 259   port->first = (port->first + 1) & (CBSIZE - 1);
 260   port->count--;
 261   enable ();
 262   return c;
 263 }
 264
 265
 266 static int
 267 dos_putc (int c, struct dos_ttystate *port)
 268 {
 269   if (port->count >= CBSIZE - 1)
 270     return -1;
 271   port->cbuf[(port->first + port->count) & (CBSIZE - 1)] = c;
 272   port->count++;
 273   return 0;
 274 }
 275 \f
 276
 277
 278 static void
 279 dos_comisr (int irq)
 280 {
 281   struct dos_ttystate *port;
 282   unsigned char iir, lsr, c;
 283
 284   disable ();                   /* Paranoia */
 285   outportb (ICU_OCW2, 0x20);    /* End-Of-Interrupt */
 286 #ifdef DOS_STATS
 287   ++intrcnt;
 288 #endif
 289
 290   port = intrupts[irq].port;
 291   if (!port)
 292     {
 293       COUNT (CNT_STRAY);
 294       return;                   /* not open */
 295     }
 296
 297   while (1)
 298     {
 299       iir = inb (port, com_iir) & IIR_IMASK;
 300       switch (iir)
 301         {
 302
 303         case IIR_RLS:
 304           lsr = inb (port, com_lsr);
 305           goto rx;
 306
 307         case IIR_RXTOUT:
 308         case IIR_RXRDY:
 309           lsr = 0;
 310
 311         rx:
 312           do
 313             {
 314               c = inb (port, com_data);
 315               if (lsr & (LSR_BI | LSR_FE | LSR_PE | LSR_OE))
 316                 {
 317                   if (lsr & (LSR_BI | LSR_FE))
 318                     port->ferr++;
 319                   else if (lsr & LSR_PE)
 320                     port->perr++;
 321                   if (lsr & LSR_OE)
 322                     port->oflo++;
 323                 }
 324
 325               if (dos_putc (c, port) < 0)
 326                 {
 327                   COUNT (CNT_ORUN);
 328                 }
 329               else
 330                 {
 331                   COUNT (CNT_RX);
 332                 }
 333             }
 334           while ((lsr = inb (port, com_lsr)) & LSR_RXRDY);
 335           break;
 336
 337         case IIR_MLSC:
 338           /* could be used to flowcontrol Tx */
 339           port->msr = inb (port, com_msr);
 340           break;
 341
 342         case IIR_TXRDY:
 343           port->txbusy = 0;
 344           break;
 345
 346         case IIR_NOPEND:
 347           /* no more pending interrupts, all done */
 348           return;
 349
 350         default:
 351           /* unexpected interrupt, ignore */
 352           break;
 353         }
 354       COUNT (iir);
 355     }
 356 }
 357
 358 #ifdef __STDC__
 359 #define ISRNAME(x) dos_comisr##x
 360 #else
 361 #define ISRNAME(x) dos_comisr/**/x
 362 #endif
 363 #define ISR(x) static void ISRNAME(x)() {dos_comisr(x);}
 364
 365 ISR (0) ISR (1) ISR (2) ISR (3)
 366 ISR (4) ISR (5) ISR (6) ISR (7)
 367
 368      typedef void (*isr_t) ();
 369
 370      static isr_t isrs[NINTR] =
 371      {
 372        ISRNAME (0), ISRNAME (1), ISRNAME (2), ISRNAME (3),
 373        ISRNAME (4), ISRNAME (5), ISRNAME (6), ISRNAME (7)
 374 };
 375 \f
 376
 377
 378      static struct intrupt *
 379        dos_hookirq (irq)
 380      unsigned int irq;
 381 {
 382   struct intrupt *intr;
 383   unsigned int vec;
 384   isr_t isr;
 385
 386   if (irq >= NINTR)
 387     return 0;
 388
 389   intr = &intrupts[irq];
 390   if (intr->inuse)
 391     return 0;
 392
 393   vec = 0x08 + irq;
 394   isr = isrs[irq];
 395
 396   /* setup real mode handler */
 397   _go32_dpmi_get_real_mode_interrupt_vector (vec, &intr->old_rmhandler);
 398
 399   intr->new_rmhandler.pm_selector = _go32_my_cs ();
 400   intr->new_rmhandler.pm_offset = (u_long) isr;
 401   if (_go32_dpmi_allocate_real_mode_callback_iret (&intr->new_rmhandler,
 402                                                    &intr->regs))
 403     {
 404       return 0;
 405     }
 406
 407   if (_go32_dpmi_set_real_mode_interrupt_vector (vec, &intr->new_rmhandler))
 408     {
 409       return 0;
 410     }
 411
 412   /* setup protected mode handler */
 413   _go32_dpmi_get_protected_mode_interrupt_vector (vec, &intr->old_pmhandler);
 414
 415   intr->new_pmhandler.pm_selector = _go32_my_cs ();
 416   intr->new_pmhandler.pm_offset = (u_long) isr;
 417   _go32_dpmi_allocate_iret_wrapper (&intr->new_pmhandler);
 418
 419   if (_go32_dpmi_set_protected_mode_interrupt_vector (vec, &intr->new_pmhandler))
 420     {
 421       return 0;
 422     }
 423
 424   /* setup interrupt controller mask */
 425   disable ();
 426   outportb (ICU_MASK, inportb (ICU_MASK) & ~(1 << irq));
 427   enable ();
 428
 429   intr->inuse = 1;
 430   return intr;
 431 }
 432
 433
 434 static void
 435 dos_unhookirq (struct intrupt *intr)
 436 {
 437   unsigned int irq, vec;
 438   unsigned char mask;
 439
 440   irq = intr - intrupts;
 441   vec = 0x08 + irq;
 442
 443   /* restore old interrupt mask bit */
 444   mask = 1 << irq;
 445   disable ();
 446   outportb (ICU_MASK, inportb (ICU_MASK) | (mask & icu_oldmask));
 447   enable ();
 448
 449   /* remove real mode handler */
 450   _go32_dpmi_set_real_mode_interrupt_vector (vec, &intr->old_rmhandler);
 451   _go32_dpmi_free_real_mode_callback (&intr->new_rmhandler);
 452
 453   /* remove protected mode handler */
 454   _go32_dpmi_set_protected_mode_interrupt_vector (vec, &intr->old_pmhandler);
 455   _go32_dpmi_free_iret_wrapper (&intr->new_pmhandler);
 456   intr->inuse = 0;
 457 }
 458 \f
 459
 460
 461 static int
 462 dos_open (serial_t scb, const char *name)
 463 {
 464   struct dos_ttystate *port;
 465   int fd, i;
 466
 467   if (strncasecmp (name, "/dev/", 5) == 0)
 468     name += 5;
 469   else if (strncasecmp (name, "\\dev\\", 5) == 0)
 470     name += 5;
 471
 472   if (strlen (name) != 4 || strncasecmp (name, "com", 3) != 0)
 473     {
 474       errno = ENOENT;
 475       return -1;
 476     }
 477
 478   if (name[3] < '1' || name[3] > '4')
 479     {
 480       errno = ENOENT;
 481       return -1;
 482     }
 483
 484   /* FIXME: this is a Bad Idea (tm)!  One should *never* invent file
 485      handles, since they might be already used by other files/devices.
 486      The Right Way to do this is to create a real handle by dup()'ing
 487      some existing one.  */
 488   fd = name[3] - '1';
 489   port = &ports[fd];
 490   if (port->refcnt++ > 0)
 491     {
 492       /* Device already opened another user.  Just point at it. */
 493       scb->fd = fd;
 494       return 0;
 495     }
 496
 497   /* force access to ID reg */
 498   outb (port, com_cfcr, 0);
 499   outb (port, com_iir, 0);
 500   for (i = 0; i < 17; i++)
 501     {
 502       if ((inb (port, com_iir) & 0x38) == 0)
 503         goto ok;
 504       (void) inb (port, com_data);      /* clear recv */
 505     }
 506   errno = ENODEV;
 507   return -1;
 508
 509 ok:
 510   /* disable all interrupts in chip */
 511   outb (port, com_ier, 0);
 512
 513   /* tentatively enable 16550 fifo, and see if it responds */
 514   outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER);
 515   sleep (1);
 516   port->fifo = ((inb (port, com_iir) & IIR_FIFO_MASK) == IIR_FIFO_MASK);
 517
 518   /* clear pending status reports. */
 519   (void) inb (port, com_lsr);
 520   (void) inb (port, com_msr);
 521
 522   /* enable external interrupt gate (to avoid floating IRQ) */
 523   outb (port, com_mcr, MCR_IENABLE);
 524
 525   /* hook up interrupt handler and initialise icu */
 526   port->intrupt = dos_hookirq (port->irq);
 527   if (!port->intrupt)
 528     {
 529       outb (port, com_mcr, 0);
 530       outb (port, com_fifo, 0);
 531       errno = ENODEV;
 532       return -1;
 533     }
 534
 535   disable ();
 536
 537   /* record port */
 538   port->intrupt->port = port;
 539   scb->fd = fd;
 540
 541   /* clear rx buffer, tx busy flag and overflow count */
 542   port->first = port->count = 0;
 543   port->txbusy = 0;
 544   port->oflo = 0;
 545
 546   /* set default baud rate and mode: 9600,8,n,1 */
 547   i = dos_baudconv (port->baudrate = 9600);
 548   outb (port, com_cfcr, CFCR_DLAB);
 549   outb (port, com_dlbl, i & 0xff);
 550   outb (port, com_dlbh, i >> 8);
 551   outb (port, com_cfcr, CFCR_8BITS);
 552
 553   /* enable all interrupts */
 554   outb (port, com_ier, IER_ETXRDY | IER_ERXRDY | IER_ERLS | IER_EMSC);
 555
 556   /* enable DTR & RTS */
 557   outb (port, com_mcr, MCR_DTR | MCR_RTS | MCR_IENABLE);
 558
 559   enable ();
 560
 561   return 0;
 562 }
 563
 564
 565 static void
 566 dos_close (serial_t scb)
 567 {
 568   struct dos_ttystate *port;
 569   struct intrupt *intrupt;
 570
 571   if (!scb)
 572     return;
 573
 574   port = &ports[scb->fd];
 575
 576   if (port->refcnt-- > 1)
 577     return;
 578
 579   if (!(intrupt = port->intrupt))
 580     return;
 581
 582   /* disable interrupts, fifo, flow control */
 583   disable ();
 584   port->intrupt = 0;
 585   intrupt->port = 0;
 586   outb (port, com_fifo, 0);
 587   outb (port, com_ier, 0);
 588   enable ();
 589
 590   /* unhook handler, and disable interrupt gate */
 591   dos_unhookirq (intrupt);
 592   outb (port, com_mcr, 0);
 593
 594   /* Check for overflow errors */
 595   if (port->oflo)
 596     {
 597       fprintf_unfiltered (gdb_stderr,
 598                           "Serial input overruns occurred.\n");
 599       fprintf_unfiltered (gdb_stderr, "This system %s handle %d baud.\n",
 600                           port->fifo ? "cannot" : "needs a 16550 to",
 601                           port->baudrate);
 602     }
 603 }
 604 \f
 605
 606
 607 static int
 608 dos_noop (serial_t scb ATTRIBUTE_UNUSED)
 609 {
 610   return 0;
 611 }
 612
 613 static void
 614 dos_raw (serial_t scb ATTRIBUTE_UNUSED)
 615 {
 616   /* Always in raw mode */
 617 }
 618
 619 static int
 620 dos_readchar (serial_t scb, int timeout)
 621 {
 622   struct dos_ttystate *port = &ports[scb->fd];
 623   long then;
 624   int c;
 625
 626   then = rawclock () + (timeout * RAWHZ);
 627   while ((c = dos_getc (port)) < 0)
 628     {
 629       if (timeout >= 0 && (rawclock () - then) >= 0)
 630         return SERIAL_TIMEOUT;
 631       notice_quit ();
 632     }
 633
 634   return c;
 635 }
 636
 637
 638 static serial_ttystate
 639 dos_get_tty_state (serial_t scb)
 640 {
 641   struct dos_ttystate *port = &ports[scb->fd];
 642   struct dos_ttystate *state;
 643
 644   /* Are they asking about a port we opened?  */
 645   if (port->refcnt <= 0)
 646     {
 647       /* We've never heard about this port.  We should fail this call,
 648          unless they are asking about one of the 3 standard handles,
 649          in which case we pretend the handle was open by us if it is
 650          connected to a terminal device.  This is beacuse Unix
 651          terminals use the serial interface, so GDB expects the
 652          standard handles to go through here.  */
 653       if (scb->fd >= 3 || !isatty (scb->fd))
 654         return NULL;
 655     }
 656
 657   state = (struct dos_ttystate *) xmalloc (sizeof *state);
 658   *state = *port;
 659   return (serial_ttystate) state;
 660 }
 661
 662 static int
 663 dos_set_tty_state (serial_t scb, serial_ttystate ttystate)
 664 {
 665   struct dos_ttystate *state;
 666
 667   state = (struct dos_ttystate *) ttystate;
 668   dos_setbaudrate (scb, state->baudrate);
 669   return 0;
 670 }
 671
 672 static int
 673 dos_noflush_set_tty_state (serial_t scb, serial_ttystate new_ttystate,
 674                            serial_ttystate old_ttystate ATTRIBUTE_UNUSED)
 675 {
 676   struct dos_ttystate *state;
 677
 678   state = (struct dos_ttystate *) new_ttystate;
 679   dos_setbaudrate (scb, state->baudrate);
 680   return 0;
 681 }
 682
 683 static int
 684 dos_flush_input (serial_t scb)
 685 {
 686   struct dos_ttystate *port = &ports[scb->fd];
 687   disable ();
 688   port->first = port->count = 0;
 689   if (port->fifo)
 690     outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_TRIGGER);
 691   enable ();
 692   return 0;
 693 }
 694
 695 static void
 696 dos_print_tty_state (serial_t scb ATTRIBUTE_UNUSED,
 697                      serial_ttystate ttystate ATTRIBUTE_UNUSED,
 698                      struct ui_file *stream ATTRIBUTE_UNUSED)
 699 {
 700   /* Nothing to print */
 701   return;
 702 }
 703
 704 static int
 705 dos_baudconv (int rate)
 706 {
 707   long x, err;
 708
 709   if (rate <= 0)
 710     return -1;
 711
 712 #define divrnd(n, q)    (((n) * 2 / (q) + 1) / 2)       /* divide and round off */
 713   x = divrnd (COMTICK, rate);
 714   if (x <= 0)
 715     return -1;
 716
 717   err = divrnd (1000 * COMTICK, x * rate) - 1000;
 718   if (err < 0)
 719     err = -err;
 720   if (err > SPEED_TOLERANCE)
 721     return -1;
 722 #undef divrnd
 723   return x;
 724 }
 725
 726
 727 static int
 728 dos_setbaudrate (serial_t scb, int rate)
 729 {
 730   struct dos_ttystate *port = &ports[scb->fd];
 731
 732   if (port->baudrate != rate)
 733     {
 734       int x;
 735       unsigned char cfcr;
 736
 737       x = dos_baudconv (rate);
 738       if (x <= 0)
 739         {
 740           fprintf_unfiltered (gdb_stderr, "%d: impossible baudrate\n", rate);
 741           errno = EINVAL;
 742           return -1;
 743         }
 744
 745       disable ();
 746       cfcr = inb (port, com_cfcr);
 747
 748       outb (port, com_cfcr, CFCR_DLAB);
 749       outb (port, com_dlbl, x & 0xff);
 750       outb (port, com_dlbh, x >> 8);
 751       outb (port, com_cfcr, cfcr);
 752       port->baudrate = rate;
 753       enable ();
 754     }
 755
 756   return 0;
 757 }
 758
 759 static int
 760 dos_setstopbits (serial_t scb, int num)
 761 {
 762   struct dos_ttystate *port = &ports[scb->fd];
 763   unsigned char cfcr;
 764
 765   disable ();
 766   cfcr = inb (port, com_cfcr);
 767
 768   switch (num)
 769     {
 770     case SERIAL_1_STOPBITS:
 771       outb (port, com_cfcr, cfcr & ~CFCR_STOPB);
 772       break;
 773     case SERIAL_1_AND_A_HALF_STOPBITS:
 774     case SERIAL_2_STOPBITS:
 775       outb (port, com_cfcr, cfcr | CFCR_STOPB);
 776       break;
 777     default:
 778       enable ();
 779       return 1;
 780     }
 781   enable ();
 782
 783   return 0;
 784 }
 785
 786 static int
 787 dos_write (serial_t scb, const char *str, int len)
 788 {
 789   volatile struct dos_ttystate *port = &ports[scb->fd];
 790   int fifosize = port->fifo ? 16 : 1;
 791   long then;
 792   int cnt;
 793
 794   while (len > 0)
 795     {
 796       /* send the data, fifosize bytes at a time */
 797       cnt = fifosize > len ? len : fifosize;
 798       port->txbusy = 1;
 799       /* Francisco Pastor <fpastor.etra-id@etra.es> says OUTSB messes
 800          up the communications with UARTs with FIFOs.  */
 801 #ifdef UART_FIFO_WORKS
 802       outportsb (port->base + com_data, str, cnt);
 803       str += cnt;
 804       len -= cnt;
 805 #else
 806       for ( ; cnt > 0; cnt--, len--)
 807         outportb (port->base + com_data, *str++);
 808 #endif
 809 #ifdef DOS_STATS
 810       cnts[CNT_TX] += cnt;
 811 #endif
 812       /* wait for transmission to complete (max 1 sec) */
 813       then = rawclock () + RAWHZ;
 814       while (port->txbusy)
 815         {
 816           if ((rawclock () - then) >= 0)
 817             {
 818               errno = EIO;
 819               return SERIAL_ERROR;
 820             }
 821         }
 822     }
 823   return 0;
 824 }
 825
 826
 827 static int
 828 dos_sendbreak (serial_t scb)
 829 {
 830   volatile struct dos_ttystate *port = &ports[scb->fd];
 831   unsigned char cfcr;
 832   long then;
 833
 834   cfcr = inb (port, com_cfcr);
 835   outb (port, com_cfcr, cfcr | CFCR_SBREAK);
 836
 837   /* 0.25 sec delay */
 838   then = rawclock () + RAWHZ / 4;
 839   while ((rawclock () - then) < 0)
 840     continue;
 841
 842   outb (port, com_cfcr, cfcr);
 843   return 0;
 844 }
 845
 846
 847 static struct serial_ops dos_ops =
 848 {
 849   "hardwire",
 850   0,
 851   dos_open,
 852   dos_close,
 853   dos_readchar,
 854   dos_write,
 855   dos_noop,                     /* flush output */
 856   dos_flush_input,
 857   dos_sendbreak,
 858   dos_raw,
 859   dos_get_tty_state,
 860   dos_set_tty_state,
 861   dos_print_tty_state,
 862   dos_noflush_set_tty_state,
 863   dos_setbaudrate,
 864   dos_setstopbits,
 865   dos_noop,                     /* wait for output to drain */
 866   (void (*)(serial_t, int))NULL /* change into async mode */
 867 };
 868
 869
 870 static void
 871 dos_info (char *arg ATTRIBUTE_UNUSED, int from_tty ATTRIBUTE_UNUSED)
 872 {
 873   struct dos_ttystate *port;
 874 #ifdef DOS_STATS
 875   int i;
 876 #endif
 877
 878   for (port = ports; port < &ports[4]; port++)
 879     {
 880       if (port->baudrate == 0)
 881         continue;
 882       printf_filtered ("Port:\tCOM%ld (%sactive)\n", (long)(port - ports) + 1,
 883                        port->intrupt ? "" : "not ");
 884       printf_filtered ("Addr:\t0x%03x (irq %d)\n", port->base, port->irq);
 885       printf_filtered ("16550:\t%s\n", port->fifo ? "yes" : "no");
 886       printf_filtered ("Speed:\t%d baud\n", port->baudrate);
 887       printf_filtered ("Errs:\tframing %d parity %d overflow %d\n\n",
 888                        port->ferr, port->perr, port->oflo);
 889     }
 890
 891 #ifdef DOS_STATS
 892   printf_filtered ("\nTotal interrupts: %d\n", intrcnt);
 893   for (i = 0; i < NCNT; i++)
 894     if (cnts[i])
 895       printf_filtered ("%s:\t%d\n", cntnames[i], cnts[i]);
 896 #endif
 897 }
 898
 899
 900 void
 901 _initialize_ser_dos (void)
 902 {
 903   serial_add_interface (&dos_ops);
 904
 905   /* Save original interrupt mask register. */
 906   icu_oldmask = inportb (ICU_MASK);
 907
 908   /* Mark fixed motherboard irqs as inuse. */
 909   intrupts[0].inuse =           /* timer tick */
 910     intrupts[1].inuse =         /* keyboard */
 911     intrupts[2].inuse = 1;      /* slave icu */
 912
 913   add_show_from_set (
 914                       add_set_cmd ("com1base", class_obscure, var_zinteger,
 915                                    (char *) &ports[0].base,
 916                                    "Set COM1 base i/o port address.",
 917                                    &setlist),
 918                       &showlist);
 919
 920   add_show_from_set (
 921                       add_set_cmd ("com1irq", class_obscure, var_zinteger,
 922                                    (char *) &ports[0].irq,
 923                                    "Set COM1 interrupt request.",
 924                                    &setlist),
 925                       &showlist);
 926
 927   add_show_from_set (
 928                       add_set_cmd ("com2base", class_obscure, var_zinteger,
 929                                    (char *) &ports[1].base,
 930                                    "Set COM2 base i/o port address.",
 931                                    &setlist),
 932                       &showlist);
 933
 934   add_show_from_set (
 935                       add_set_cmd ("com2irq", class_obscure, var_zinteger,
 936                                    (char *) &ports[1].irq,
 937                                    "Set COM2 interrupt request.",
 938                                    &setlist),
 939                       &showlist);
 940
 941   add_show_from_set (
 942                       add_set_cmd ("com3base", class_obscure, var_zinteger,
 943                                    (char *) &ports[2].base,
 944                                    "Set COM3 base i/o port address.",
 945                                    &setlist),
 946                       &showlist);
 947
 948   add_show_from_set (
 949                       add_set_cmd ("com3irq", class_obscure, var_zinteger,
 950                                    (char *) &ports[2].irq,
 951                                    "Set COM3 interrupt request.",
 952                                    &setlist),
 953                       &showlist);
 954
 955   add_show_from_set (
 956                       add_set_cmd ("com4base", class_obscure, var_zinteger,
 957                                    (char *) &ports[3].base,
 958                                    "Set COM4 base i/o port address.",
 959                                    &setlist),
 960                       &showlist);
 961
 962   add_show_from_set (
 963                       add_set_cmd ("com4irq", class_obscure, var_zinteger,
 964                                    (char *) &ports[3].irq,
 965                                    "Set COM4 interrupt request.",
 966                                    &setlist),
 967                       &showlist);
 968
 969   add_info ("serial", dos_info,
 970             "Print DOS serial port status.");
 971 }