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
 218   }
 219   ,
 220   {
 221     COM2ADDR, 3
 222   }
 223   ,
 224   {
 225     COM3ADDR, 4
 226   }
 227   ,
 228   {
 229     COM4ADDR, 3
 230   }
 231 };
 232
 233 static int dos_open PARAMS ((serial_t scb, const char *name));
 234 static void dos_raw PARAMS ((serial_t scb));
 235 static int dos_readchar PARAMS ((serial_t scb, int timeout));
 236 static int dos_setbaudrate PARAMS ((serial_t scb, int rate));
 237 static int dos_write PARAMS ((serial_t scb, const char *str, int len));
 238 static void dos_close PARAMS ((serial_t scb));
 239 static serial_ttystate dos_get_tty_state PARAMS ((serial_t scb));
 240 static int dos_set_tty_state PARAMS ((serial_t scb, serial_ttystate state));
 241 static int dos_baudconv PARAMS ((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 (port)
 251      volatile struct dos_ttystate *port;
 252 {
 253   int c;
 254
 255   if (port->count == 0)
 256     return -1;
 257
 258   c = port->cbuf[port->first];
 259   disable ();
 260   port->first = (port->first + 1) & (CBSIZE - 1);
 261   port->count--;
 262   enable ();
 263   return c;
 264 }
 265
 266
 267 static int
 268 dos_putc (c, port)
 269      int c;
 270      struct dos_ttystate *port;
 271 {
 272   if (port->count >= CBSIZE - 1)
 273     return -1;
 274   port->cbuf[(port->first + port->count) & (CBSIZE - 1)] = c;
 275   port->count++;
 276   return 0;
 277 }
 278 \f
 279
 280
 281 static void
 282 dos_comisr (irq)
 283      int irq;
 284 {
 285   struct dos_ttystate *port;
 286   unsigned char iir, lsr, c;
 287
 288   disable ();                   /* Paranoia */
 289   outportb (ICU_OCW2, 0x20);    /* End-Of-Interrupt */
 290 #ifdef DOS_STATS
 291   ++intrcnt;
 292 #endif
 293
 294   port = intrupts[irq].port;
 295   if (!port)
 296     {
 297       COUNT (CNT_STRAY);
 298       return;                   /* not open */
 299     }
 300
 301   while (1)
 302     {
 303       iir = inb (port, com_iir) & IIR_IMASK;
 304       switch (iir)
 305         {
 306
 307         case IIR_RLS:
 308           lsr = inb (port, com_lsr);
 309           goto rx;
 310
 311         case IIR_RXTOUT:
 312         case IIR_RXRDY:
 313           lsr = 0;
 314
 315         rx:
 316           do
 317             {
 318               c = inb (port, com_data);
 319               if (lsr & (LSR_BI | LSR_FE | LSR_PE | LSR_OE))
 320                 {
 321                   if (lsr & (LSR_BI | LSR_FE))
 322                     port->ferr++;
 323                   else if (lsr & LSR_PE)
 324                     port->perr++;
 325                   if (lsr & LSR_OE)
 326                     port->oflo++;
 327                 }
 328
 329               if (dos_putc (c, port) < 0)
 330                 {
 331                   COUNT (CNT_ORUN);
 332                 }
 333               else
 334                 {
 335                   COUNT (CNT_RX);
 336                 }
 337             }
 338           while ((lsr = inb (port, com_lsr)) & LSR_RXRDY);
 339           break;
 340
 341         case IIR_MLSC:
 342           /* could be used to flowcontrol Tx */
 343           port->msr = inb (port, com_msr);
 344           break;
 345
 346         case IIR_TXRDY:
 347           port->txbusy = 0;
 348           break;
 349
 350         case IIR_NOPEND:
 351           /* no more pending interrupts, all done */
 352           return;
 353
 354         default:
 355           /* unexpected interrupt, ignore */
 356           break;
 357         }
 358       COUNT (iir);
 359     }
 360 }
 361
 362 #ifdef __STDC__
 363 #define ISRNAME(x) dos_comisr##x
 364 #else
 365 #define ISRNAME(x) dos_comisr/**/x
 366 #endif
 367 #define ISR(x) static void ISRNAME(x)() {dos_comisr(x);}
 368
 369 ISR (0) ISR (1) ISR (2) ISR (3)
 370 ISR (4) ISR (5) ISR (6) ISR (7)
 371
 372      typedef void (*isr_t) ();
 373
 374      static isr_t isrs[NINTR] =
 375      {
 376        ISRNAME (0), ISRNAME (1), ISRNAME (2), ISRNAME (3),
 377        ISRNAME (4), ISRNAME (5), ISRNAME (6), ISRNAME (7)
 378 };
 379 \f
 380
 381
 382      static struct intrupt *
 383        dos_hookirq (irq)
 384      unsigned int irq;
 385 {
 386   struct intrupt *intr;
 387   unsigned int vec;
 388   isr_t isr;
 389
 390   if (irq >= NINTR)
 391     return 0;
 392
 393   intr = &intrupts[irq];
 394   if (intr->inuse)
 395     return 0;
 396
 397   vec = 0x08 + irq;
 398   isr = isrs[irq];
 399
 400   /* setup real mode handler */
 401   _go32_dpmi_get_real_mode_interrupt_vector (vec, &intr->old_rmhandler);
 402
 403   intr->new_rmhandler.pm_selector = _go32_my_cs ();
 404   intr->new_rmhandler.pm_offset = (u_long) isr;
 405   if (_go32_dpmi_allocate_real_mode_callback_iret (&intr->new_rmhandler,
 406                                                    &intr->regs))
 407     {
 408       return 0;
 409     }
 410
 411   if (_go32_dpmi_set_real_mode_interrupt_vector (vec, &intr->new_rmhandler))
 412     {
 413       return 0;
 414     }
 415
 416   /* setup protected mode handler */
 417   _go32_dpmi_get_protected_mode_interrupt_vector (vec, &intr->old_pmhandler);
 418
 419   intr->new_pmhandler.pm_selector = _go32_my_cs ();
 420   intr->new_pmhandler.pm_offset = (u_long) isr;
 421   _go32_dpmi_allocate_iret_wrapper (&intr->new_pmhandler);
 422
 423   if (_go32_dpmi_set_protected_mode_interrupt_vector (vec, &intr->new_pmhandler))
 424     {
 425       return 0;
 426     }
 427
 428   /* setup interrupt controller mask */
 429   disable ();
 430   outportb (ICU_MASK, inportb (ICU_MASK) & ~(1 << irq));
 431   enable ();
 432
 433   intr->inuse = 1;
 434   return intr;
 435 }
 436
 437
 438 static void
 439 dos_unhookirq (intr)
 440      struct intrupt *intr;
 441 {
 442   unsigned int irq, vec;
 443   unsigned char mask;
 444
 445   irq = intr - intrupts;
 446   vec = 0x08 + irq;
 447
 448   /* restore old interrupt mask bit */
 449   mask = 1 << irq;
 450   disable ();
 451   outportb (ICU_MASK, inportb (ICU_MASK) | (mask & icu_oldmask));
 452   enable ();
 453
 454   /* remove real mode handler */
 455   _go32_dpmi_set_real_mode_interrupt_vector (vec, &intr->old_rmhandler);
 456   _go32_dpmi_free_real_mode_callback (&intr->new_rmhandler);
 457
 458   /* remove protected mode handler */
 459   _go32_dpmi_set_protected_mode_interrupt_vector (vec, &intr->old_pmhandler);
 460   _go32_dpmi_free_iret_wrapper (&intr->new_pmhandler);
 461   intr->inuse = 0;
 462 }
 463 \f
 464
 465
 466 static int
 467 dos_open (scb, name)
 468      serial_t scb;
 469      const char *name;
 470 {
 471   struct dos_ttystate *port;
 472   int fd, i;
 473
 474   if (strncasecmp (name, "/dev/", 5) == 0)
 475     name += 5;
 476   else if (strncasecmp (name, "\\dev\\", 5) == 0)
 477     name += 5;
 478
 479   if (strlen (name) != 4 || strncasecmp (name, "com", 3) != 0)
 480     {
 481       errno = ENOENT;
 482       return -1;
 483     }
 484
 485   if (name[3] < '1' || name[3] > '4')
 486     {
 487       errno = ENOENT;
 488       return -1;
 489     }
 490
 491   fd = name[3] - '1';
 492   port = &ports[fd];
 493   if (port->refcnt++ > 0)
 494     {
 495       /* Device already opened another user.  Just point at it. */
 496       scb->fd = fd;
 497       return 0;
 498     }
 499
 500   /* force access to ID reg */
 501   outb (port, com_cfcr, 0);
 502   outb (port, com_iir, 0);
 503   for (i = 0; i < 17; i++)
 504     {
 505       if ((inb (port, com_iir) & 0x38) == 0)
 506         goto ok;
 507       (void) inb (port, com_data);      /* clear recv */
 508     }
 509   errno = ENODEV;
 510   return -1;
 511
 512 ok:
 513   /* disable all interrupts in chip */
 514   outb (port, com_ier, 0);
 515
 516   /* tentatively enable 16550 fifo, and see if it responds */
 517   outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER);
 518   sleep (1);
 519   port->fifo = ((inb (port, com_iir) & IIR_FIFO_MASK) == IIR_FIFO_MASK);
 520
 521   /* clear pending status reports. */
 522   (void) inb (port, com_lsr);
 523   (void) inb (port, com_msr);
 524
 525   /* enable external interrupt gate (to avoid floating IRQ) */
 526   outb (port, com_mcr, MCR_IENABLE);
 527
 528   /* hook up interrupt handler and initialise icu */
 529   port->intrupt = dos_hookirq (port->irq);
 530   if (!port->intrupt)
 531     {
 532       outb (port, com_mcr, 0);
 533       outb (port, com_fifo, 0);
 534       errno = ENODEV;
 535       return -1;
 536     }
 537
 538   disable ();
 539
 540   /* record port */
 541   port->intrupt->port = port;
 542   scb->fd = fd;
 543
 544   /* clear rx buffer, tx busy flag and overflow count */
 545   port->first = port->count = 0;
 546   port->txbusy = 0;
 547   port->oflo = 0;
 548
 549   /* set default baud rate and mode: 9600,8,n,1 */
 550   i = dos_baudconv (port->baudrate = 9600);
 551   outb (port, com_cfcr, CFCR_DLAB);
 552   outb (port, com_dlbl, i & 0xff);
 553   outb (port, com_dlbh, i >> 8);
 554   outb (port, com_cfcr, CFCR_8BITS);
 555
 556   /* enable all interrupts */
 557   outb (port, com_ier, IER_ETXRDY | IER_ERXRDY | IER_ERLS | IER_EMSC);
 558
 559   /* enable DTR & RTS */
 560   outb (port, com_mcr, MCR_DTR | MCR_RTS | MCR_IENABLE);
 561
 562   enable ();
 563
 564   return 0;
 565 }
 566
 567
 568 static void
 569 dos_close (scb)
 570      serial_t scb;
 571 {
 572   struct dos_ttystate *port;
 573   struct intrupt *intrupt;
 574
 575   if (!scb)
 576     return;
 577
 578   port = &ports[scb->fd];
 579
 580   if (port->refcnt-- > 1)
 581     return;
 582
 583   if (!(intrupt = port->intrupt))
 584     return;
 585
 586   /* disable interrupts, fifo, flow control */
 587   disable ();
 588   port->intrupt = 0;
 589   intrupt->port = 0;
 590   outb (port, com_fifo, 0);
 591   outb (port, com_ier, 0);
 592   enable ();
 593
 594   /* unhook handler, and disable interrupt gate */
 595   dos_unhookirq (intrupt);
 596   outb (port, com_mcr, 0);
 597
 598   /* Check for overflow errors */
 599   if (port->oflo)
 600     {
 601       fprintf_unfiltered (gdb_stderr,
 602                           "Serial input overruns occurred.\n");
 603       fprintf_unfiltered (gdb_stderr, "This system %s handle %d baud.\n",
 604                           port->fifo ? "cannot" : "needs a 16550 to",
 605                           port->baudrate);
 606     }
 607 }
 608 \f
 609
 610
 611 static int
 612 dos_noop (scb)
 613      serial_t scb;
 614 {
 615   return 0;
 616 }
 617
 618 static void
 619 dos_raw (scb)
 620      serial_t scb;
 621 {
 622   /* Always in raw mode */
 623 }
 624
 625 static int
 626 dos_readchar (scb, timeout)
 627      serial_t scb;
 628      int timeout;
 629 {
 630   struct dos_ttystate *port = &ports[scb->fd];
 631   long then;
 632   int c;
 633
 634   then = rawclock () + (timeout * RAWHZ);
 635   while ((c = dos_getc (port)) < 0)
 636     {
 637       if (timeout >= 0 && (rawclock () - then) >= 0)
 638         return SERIAL_TIMEOUT;
 639       notice_quit ();
 640     }
 641
 642   return c;
 643 }
 644
 645
 646 static serial_ttystate
 647 dos_get_tty_state (scb)
 648      serial_t scb;
 649 {
 650   struct dos_ttystate *port = &ports[scb->fd];
 651   struct dos_ttystate *state;
 652
 653   state = (struct dos_ttystate *) xmalloc (sizeof *state);
 654   *state = *port;
 655   return (serial_ttystate) state;
 656 }
 657
 658 static int
 659 dos_set_tty_state (scb, ttystate)
 660      serial_t scb;
 661      serial_ttystate ttystate;
 662 {
 663   struct dos_ttystate *state;
 664
 665   state = (struct dos_ttystate *) ttystate;
 666   dos_setbaudrate (scb, state->baudrate);
 667   return 0;
 668 }
 669
 670 static int
 671 dos_noflush_set_tty_state (scb, new_ttystate, old_ttystate)
 672      serial_t scb;
 673      serial_ttystate new_ttystate;
 674      serial_ttystate old_ttystate;
 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 (scb)
 685      serial_t scb;
 686 {
 687   struct dos_ttystate *port = &ports[scb->fd];
 688   disable ();
 689   port->first = port->count = 0;
 690   if (port->fifo)
 691     outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_TRIGGER);
 692   enable ();
 693   return 0;
 694 }
 695
 696 static void
 697 dos_print_tty_state (serial_t scb,
 698                      serial_ttystate ttystate,
 699                      struct ui_file *stream)
 700 {
 701   /* Nothing to print */
 702   return;
 703 }
 704
 705 static int
 706 dos_baudconv (rate)
 707      int rate;
 708 {
 709   long x, err;
 710
 711   if (rate <= 0)
 712     return -1;
 713
 714 #define divrnd(n, q)    (((n) * 2 / (q) + 1) / 2)       /* divide and round off */
 715   x = divrnd (COMTICK, rate);
 716   if (x <= 0)
 717     return -1;
 718
 719   err = divrnd (1000 * COMTICK, x * rate) - 1000;
 720   if (err < 0)
 721     err = -err;
 722   if (err > SPEED_TOLERANCE)
 723     return -1;
 724 #undef divrnd
 725   return x;
 726 }
 727
 728
 729 static int
 730 dos_setbaudrate (scb, rate)
 731      serial_t scb;
 732      int rate;
 733 {
 734   struct dos_ttystate *port = &ports[scb->fd];
 735
 736   if (port->baudrate != rate)
 737     {
 738       int x;
 739       unsigned char cfcr;
 740
 741       x = dos_baudconv (rate);
 742       if (x <= 0)
 743         {
 744           fprintf_unfiltered (gdb_stderr, "%d: impossible baudrate\n", rate);
 745           errno = EINVAL;
 746           return -1;
 747         }
 748
 749       disable ();
 750       cfcr = inb (port, com_cfcr);
 751
 752       outb (port, com_cfcr, CFCR_DLAB);
 753       outb (port, com_dlbl, x & 0xff);
 754       outb (port, com_dlbh, x >> 8);
 755       outb (port, com_cfcr, cfcr);
 756       port->baudrate = rate;
 757       enable ();
 758     }
 759
 760   return 0;
 761 }
 762
 763 static int
 764 dos_setstopbits (scb, num)
 765      serial_t scb;
 766      int num;
 767 {
 768   struct dos_ttystate *port = &ports[scb->fd];
 769   unsigned char cfcr;
 770
 771   disable ();
 772   cfcr = inb (port, com_cfcr);
 773
 774   switch (num)
 775     {
 776     case SERIAL_1_STOPBITS:
 777       outb (port, com_cfcr, cfcr & ~CFCR_STOPB);
 778       break;
 779     case SERIAL_1_AND_A_HALF_STOPBITS:
 780     case SERIAL_2_STOPBITS:
 781       outb (port, com_cfcr, cfcr | CFCR_STOPB);
 782       break;
 783     default:
 784       enable ();
 785       return 1;
 786     }
 787   enable ();
 788
 789   return 0;
 790 }
 791
 792 static int
 793 dos_write (scb, str, len)
 794      serial_t scb;
 795      const char *str;
 796      int len;
 797 {
 798   volatile struct dos_ttystate *port = &ports[scb->fd];
 799   int fifosize = port->fifo ? 16 : 1;
 800   long then;
 801   int cnt;
 802
 803   while (len > 0)
 804     {
 805       /* send the data, fifosize bytes at a time */
 806       cnt = fifosize > len ? len : fifosize;
 807       port->txbusy = 1;
 808       outportsb (port->base + com_data, str, cnt);
 809       str += cnt;
 810       len -= cnt;
 811 #ifdef DOS_STATS
 812       cnts[CNT_TX] += cnt;
 813 #endif
 814       /* wait for transmission to complete (max 1 sec) */
 815       then = rawclock () + RAWHZ;
 816       while (port->txbusy)
 817         {
 818           if ((rawclock () - then) >= 0)
 819             {
 820               errno = EIO;
 821               return SERIAL_ERROR;
 822             }
 823         }
 824     }
 825   return 0;
 826 }
 827
 828
 829 static int
 830 dos_sendbreak (scb)
 831      serial_t scb;
 832 {
 833   volatile struct dos_ttystate *port = &ports[scb->fd];
 834   unsigned char cfcr;
 835   long then;
 836
 837   cfcr = inb (port, com_cfcr);
 838   outb (port, com_cfcr, cfcr | CFCR_SBREAK);
 839
 840   /* 0.25 sec delay */
 841   then = rawclock () + RAWHZ / 4;
 842   while ((rawclock () - then) < 0)
 843     continue;
 844
 845   outb (port, com_cfcr, cfcr);
 846   return 0;
 847 }
 848
 849
 850 static struct serial_ops dos_ops =
 851 {
 852   "hardwire",
 853   0,
 854   dos_open,
 855   dos_close,
 856   dos_readchar,
 857   dos_write,
 858   dos_noop,                     /* flush output */
 859   dos_flush_input,
 860   dos_sendbreak,
 861   dos_raw,
 862   dos_get_tty_state,
 863   dos_set_tty_state,
 864   dos_print_tty_state,
 865   dos_noflush_set_tty_state,
 866   dos_setbaudrate,
 867   dos_setstopbits,
 868   dos_noop,                     /* wait for output to drain */
 869 };
 870
 871
 872 static void
 873 dos_info (arg, from_tty)
 874      char *arg;
 875      int from_tty;
 876 {
 877   struct dos_ttystate *port;
 878   int i;
 879
 880   for (port = ports; port < &ports[4]; port++)
 881     {
 882       if (port->baudrate == 0)
 883         continue;
 884       printf_filtered ("Port:\tCOM%d (%sactive)\n", port - ports + 1,
 885                        port->intrupt ? "" : "not ");
 886       printf_filtered ("Addr:\t0x%03x (irq %d)\n", port->base, port->irq);
 887       printf_filtered ("16550:\t%s\n", port->fifo ? "yes" : "no");
 888       printf_filtered ("Speed:\t%d baud\n", port->baudrate);
 889       printf_filtered ("Errs:\tframing %d parity %d overflow %d\n\n",
 890                        port->ferr, port->perr, port->oflo);
 891     }
 892
 893 #ifdef DOS_STATS
 894   printf_filtered ("\nTotal interrupts: %d\n", intrcnt);
 895   for (i = 0; i < NCNT; i++)
 896     if (cnts[i])
 897       printf_filtered ("%s:\t%d\n", cntnames[i], cnts[i]);
 898 #endif
 899 }
 900
 901
 902 void
 903 _initialize_ser_dos ()
 904 {
 905   struct cmd_list_element *c;
 906
 907   serial_add_interface (&dos_ops);
 908
 909   /* Save original interrupt mask register. */
 910   icu_oldmask = inportb (ICU_MASK);
 911
 912   /* Mark fixed motherboard irqs as inuse. */
 913   intrupts[0].inuse =           /* timer tick */
 914     intrupts[1].inuse =         /* keyboard */
 915     intrupts[2].inuse = 1;      /* slave icu */
 916
 917   add_show_from_set (
 918                       add_set_cmd ("com1base", class_obscure, var_zinteger,
 919                                    (char *) &ports[0].base,
 920                                    "Set COM1 base i/o port address.",
 921                                    &setlist),
 922                       &showlist);
 923
 924   add_show_from_set (
 925                       add_set_cmd ("com1irq", class_obscure, var_zinteger,
 926                                    (char *) &ports[0].irq,
 927                                    "Set COM1 interrupt request.",
 928                                    &setlist),
 929                       &showlist);
 930
 931   add_show_from_set (
 932                       add_set_cmd ("com2base", class_obscure, var_zinteger,
 933                                    (char *) &ports[1].base,
 934                                    "Set COM2 base i/o port address.",
 935                                    &setlist),
 936                       &showlist);
 937
 938   add_show_from_set (
 939                       add_set_cmd ("com2irq", class_obscure, var_zinteger,
 940                                    (char *) &ports[1].irq,
 941                                    "Set COM2 interrupt request.",
 942                                    &setlist),
 943                       &showlist);
 944
 945   add_show_from_set (
 946                       add_set_cmd ("com3base", class_obscure, var_zinteger,
 947                                    (char *) &ports[2].base,
 948                                    "Set COM3 base i/o port address.",
 949                                    &setlist),
 950                       &showlist);
 951
 952   add_show_from_set (
 953                       add_set_cmd ("com3irq", class_obscure, var_zinteger,
 954                                    (char *) &ports[2].irq,
 955                                    "Set COM3 interrupt request.",
 956                                    &setlist),
 957                       &showlist);
 958
 959   add_show_from_set (
 960                       add_set_cmd ("com4base", class_obscure, var_zinteger,
 961                                    (char *) &ports[3].base,
 962                                    "Set COM4 base i/o port address.",
 963                                    &setlist),
 964                       &showlist);
 965
 966   add_show_from_set (
 967                       add_set_cmd ("com4irq", class_obscure, var_zinteger,
 968                                    (char *) &ports[3].irq,
 969                                    "Set COM4 interrupt request.",
 970                                    &setlist),
 971                       &showlist);
 972
 973   add_info ("serial", dos_info,
 974             "Print DOS serial port status.");
 975 }