1 /* Remote serial interface for local (hardwired) serial ports for GO32.
2 Copyright 1992, 1993, 2000 Free Software Foundation, Inc.
4 Contributed by Nigel Stephens, Algorithmics Ltd. (nigel@algor.co.uk).
6 This version uses DPMI interrupts to handle buffered i/o
7 without the separate "asynctsr" program.
9 This file is part of GDB.
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.
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.
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. */
32 * NS16550 UART registers
35 #define COM1ADDR 0x3f8
36 #define COM2ADDR 0x2f8
37 #define COM3ADDR 0x3e8
38 #define COM4ADDR 0x3e0
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) */
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.
58 #define COMTICK (1843200/16)
59 #define SPEED_TOLERANCE 30 /* thousandths; real == desired +- 3.0% */
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 */
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 */
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 */
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 */
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 */
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
120 /* modem status register */
125 #define MSR_DDCD 0x08
126 #define MSR_TERI 0x04
127 #define MSR_DDSR 0x02
128 #define MSR_DCTS 0x01
134 typedef unsigned long u_long;
136 /* 16550 rx fifo trigger point */
137 #define FIFO_TRIGGER FIFO_TRIGGER_4
139 /* input buffer size */
142 /* return raw 18Hz clock count */
143 extern long rawclock (void);
155 static int cnts[NCNT];
156 static char *cntnames[NCNT] =
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",
164 "rxcnt", "txcnt", "stray", "swoflo"
167 #define COUNT(x) cnts[x]++
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)
177 /* Original interrupt controller mask register. */
178 unsigned char icu_oldmask;
180 /* Maximum of 8 interrupts (we don't handle the slave icu yet). */
183 static struct intrupt
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;
196 static struct dos_ttystate
201 struct intrupt *intrupt;
204 unsigned char cbuf[CBSIZE];
208 unsigned char old_mcr;
217 COM1ADDR, 4, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
221 COM2ADDR, 3, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
225 COM3ADDR, 4, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
229 COM4ADDR, 3, 0, NULL, 0, 0, "", 0, 0, 0, 0, 0, 0, 0, 0
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);
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");
250 dos_getc (volatile struct dos_ttystate *port)
254 if (port->count == 0)
257 c = port->cbuf[port->first];
259 port->first = (port->first + 1) & (CBSIZE - 1);
267 dos_putc (int c, struct dos_ttystate *port)
269 if (port->count >= CBSIZE - 1)
271 port->cbuf[(port->first + port->count) & (CBSIZE - 1)] = c;
281 struct dos_ttystate *port;
282 unsigned char iir, lsr, c;
284 disable (); /* Paranoia */
285 outportb (ICU_OCW2, 0x20); /* End-Of-Interrupt */
290 port = intrupts[irq].port;
294 return; /* not open */
299 iir = inb (port, com_iir) & IIR_IMASK;
304 lsr = inb (port, com_lsr);
314 c = inb (port, com_data);
315 if (lsr & (LSR_BI | LSR_FE | LSR_PE | LSR_OE))
317 if (lsr & (LSR_BI | LSR_FE))
319 else if (lsr & LSR_PE)
325 if (dos_putc (c, port) < 0)
334 while ((lsr = inb (port, com_lsr)) & LSR_RXRDY);
338 /* could be used to flowcontrol Tx */
339 port->msr = inb (port, com_msr);
347 /* no more pending interrupts, all done */
351 /* unexpected interrupt, ignore */
358 #define ISRNAME(x) dos_comisr##x
359 #define ISR(x) static void ISRNAME(x)() {dos_comisr(x);}
361 ISR (0) ISR (1) ISR (2) ISR (3)
362 ISR (4) ISR (5) ISR (6) ISR (7)
364 typedef void (*isr_t) ();
366 static isr_t isrs[NINTR] =
368 ISRNAME (0), ISRNAME (1), ISRNAME (2), ISRNAME (3),
369 ISRNAME (4), ISRNAME (5), ISRNAME (6), ISRNAME (7)
374 static struct intrupt *
378 struct intrupt *intr;
385 intr = &intrupts[irq];
392 /* setup real mode handler */
393 _go32_dpmi_get_real_mode_interrupt_vector (vec, &intr->old_rmhandler);
395 intr->new_rmhandler.pm_selector = _go32_my_cs ();
396 intr->new_rmhandler.pm_offset = (u_long) isr;
397 if (_go32_dpmi_allocate_real_mode_callback_iret (&intr->new_rmhandler,
403 if (_go32_dpmi_set_real_mode_interrupt_vector (vec, &intr->new_rmhandler))
408 /* setup protected mode handler */
409 _go32_dpmi_get_protected_mode_interrupt_vector (vec, &intr->old_pmhandler);
411 intr->new_pmhandler.pm_selector = _go32_my_cs ();
412 intr->new_pmhandler.pm_offset = (u_long) isr;
413 _go32_dpmi_allocate_iret_wrapper (&intr->new_pmhandler);
415 if (_go32_dpmi_set_protected_mode_interrupt_vector (vec, &intr->new_pmhandler))
420 /* setup interrupt controller mask */
422 outportb (ICU_MASK, inportb (ICU_MASK) & ~(1 << irq));
431 dos_unhookirq (struct intrupt *intr)
433 unsigned int irq, vec;
436 irq = intr - intrupts;
439 /* restore old interrupt mask bit */
442 outportb (ICU_MASK, inportb (ICU_MASK) | (mask & icu_oldmask));
445 /* remove real mode handler */
446 _go32_dpmi_set_real_mode_interrupt_vector (vec, &intr->old_rmhandler);
447 _go32_dpmi_free_real_mode_callback (&intr->new_rmhandler);
449 /* remove protected mode handler */
450 _go32_dpmi_set_protected_mode_interrupt_vector (vec, &intr->old_pmhandler);
451 _go32_dpmi_free_iret_wrapper (&intr->new_pmhandler);
458 dos_open (serial_t scb, const char *name)
460 struct dos_ttystate *port;
463 if (strncasecmp (name, "/dev/", 5) == 0)
465 else if (strncasecmp (name, "\\dev\\", 5) == 0)
468 if (strlen (name) != 4 || strncasecmp (name, "com", 3) != 0)
474 if (name[3] < '1' || name[3] > '4')
480 /* FIXME: this is a Bad Idea (tm)! One should *never* invent file
481 handles, since they might be already used by other files/devices.
482 The Right Way to do this is to create a real handle by dup()'ing
483 some existing one. */
486 if (port->refcnt++ > 0)
488 /* Device already opened another user. Just point at it. */
493 /* force access to ID reg */
494 outb (port, com_cfcr, 0);
495 outb (port, com_iir, 0);
496 for (i = 0; i < 17; i++)
498 if ((inb (port, com_iir) & 0x38) == 0)
500 (void) inb (port, com_data); /* clear recv */
506 /* disable all interrupts in chip */
507 outb (port, com_ier, 0);
509 /* tentatively enable 16550 fifo, and see if it responds */
510 outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER);
512 port->fifo = ((inb (port, com_iir) & IIR_FIFO_MASK) == IIR_FIFO_MASK);
514 /* clear pending status reports. */
515 (void) inb (port, com_lsr);
516 (void) inb (port, com_msr);
518 /* enable external interrupt gate (to avoid floating IRQ) */
519 outb (port, com_mcr, MCR_IENABLE);
521 /* hook up interrupt handler and initialise icu */
522 port->intrupt = dos_hookirq (port->irq);
525 outb (port, com_mcr, 0);
526 outb (port, com_fifo, 0);
534 port->intrupt->port = port;
537 /* clear rx buffer, tx busy flag and overflow count */
538 port->first = port->count = 0;
542 /* set default baud rate and mode: 9600,8,n,1 */
543 i = dos_baudconv (port->baudrate = 9600);
544 outb (port, com_cfcr, CFCR_DLAB);
545 outb (port, com_dlbl, i & 0xff);
546 outb (port, com_dlbh, i >> 8);
547 outb (port, com_cfcr, CFCR_8BITS);
549 /* enable all interrupts */
550 outb (port, com_ier, IER_ETXRDY | IER_ERXRDY | IER_ERLS | IER_EMSC);
552 /* enable DTR & RTS */
553 outb (port, com_mcr, MCR_DTR | MCR_RTS | MCR_IENABLE);
562 dos_close (serial_t scb)
564 struct dos_ttystate *port;
565 struct intrupt *intrupt;
570 port = &ports[scb->fd];
572 if (port->refcnt-- > 1)
575 if (!(intrupt = port->intrupt))
578 /* disable interrupts, fifo, flow control */
582 outb (port, com_fifo, 0);
583 outb (port, com_ier, 0);
586 /* unhook handler, and disable interrupt gate */
587 dos_unhookirq (intrupt);
588 outb (port, com_mcr, 0);
590 /* Check for overflow errors */
593 fprintf_unfiltered (gdb_stderr,
594 "Serial input overruns occurred.\n");
595 fprintf_unfiltered (gdb_stderr, "This system %s handle %d baud.\n",
596 port->fifo ? "cannot" : "needs a 16550 to",
604 dos_noop (serial_t scb ATTRIBUTE_UNUSED)
610 dos_raw (serial_t scb ATTRIBUTE_UNUSED)
612 /* Always in raw mode */
616 dos_readchar (serial_t scb, int timeout)
618 struct dos_ttystate *port = &ports[scb->fd];
622 then = rawclock () + (timeout * RAWHZ);
623 while ((c = dos_getc (port)) < 0)
625 if (timeout >= 0 && (rawclock () - then) >= 0)
626 return SERIAL_TIMEOUT;
634 static serial_ttystate
635 dos_get_tty_state (serial_t scb)
637 struct dos_ttystate *port = &ports[scb->fd];
638 struct dos_ttystate *state;
640 /* Are they asking about a port we opened? */
641 if (port->refcnt <= 0)
643 /* We've never heard about this port. We should fail this call,
644 unless they are asking about one of the 3 standard handles,
645 in which case we pretend the handle was open by us if it is
646 connected to a terminal device. This is beacuse Unix
647 terminals use the serial interface, so GDB expects the
648 standard handles to go through here. */
649 if (scb->fd >= 3 || !isatty (scb->fd))
653 state = (struct dos_ttystate *) xmalloc (sizeof *state);
655 return (serial_ttystate) state;
659 dos_set_tty_state (serial_t scb, serial_ttystate ttystate)
661 struct dos_ttystate *state;
663 state = (struct dos_ttystate *) ttystate;
664 dos_setbaudrate (scb, state->baudrate);
669 dos_noflush_set_tty_state (serial_t scb, serial_ttystate new_ttystate,
670 serial_ttystate old_ttystate ATTRIBUTE_UNUSED)
672 struct dos_ttystate *state;
674 state = (struct dos_ttystate *) new_ttystate;
675 dos_setbaudrate (scb, state->baudrate);
680 dos_flush_input (serial_t scb)
682 struct dos_ttystate *port = &ports[scb->fd];
684 port->first = port->count = 0;
686 outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_TRIGGER);
692 dos_print_tty_state (serial_t scb ATTRIBUTE_UNUSED,
693 serial_ttystate ttystate ATTRIBUTE_UNUSED,
694 struct ui_file *stream ATTRIBUTE_UNUSED)
696 /* Nothing to print */
701 dos_baudconv (int rate)
708 #define divrnd(n, q) (((n) * 2 / (q) + 1) / 2) /* divide and round off */
709 x = divrnd (COMTICK, rate);
713 err = divrnd (1000 * COMTICK, x * rate) - 1000;
716 if (err > SPEED_TOLERANCE)
724 dos_setbaudrate (serial_t scb, int rate)
726 struct dos_ttystate *port = &ports[scb->fd];
728 if (port->baudrate != rate)
733 x = dos_baudconv (rate);
736 fprintf_unfiltered (gdb_stderr, "%d: impossible baudrate\n", rate);
742 cfcr = inb (port, com_cfcr);
744 outb (port, com_cfcr, CFCR_DLAB);
745 outb (port, com_dlbl, x & 0xff);
746 outb (port, com_dlbh, x >> 8);
747 outb (port, com_cfcr, cfcr);
748 port->baudrate = rate;
756 dos_setstopbits (serial_t scb, int num)
758 struct dos_ttystate *port = &ports[scb->fd];
762 cfcr = inb (port, com_cfcr);
766 case SERIAL_1_STOPBITS:
767 outb (port, com_cfcr, cfcr & ~CFCR_STOPB);
769 case SERIAL_1_AND_A_HALF_STOPBITS:
770 case SERIAL_2_STOPBITS:
771 outb (port, com_cfcr, cfcr | CFCR_STOPB);
783 dos_write (serial_t scb, const char *str, int len)
785 volatile struct dos_ttystate *port = &ports[scb->fd];
786 int fifosize = port->fifo ? 16 : 1;
792 /* send the data, fifosize bytes at a time */
793 cnt = fifosize > len ? len : fifosize;
795 /* Francisco Pastor <fpastor.etra-id@etra.es> says OUTSB messes
796 up the communications with UARTs with FIFOs. */
797 #ifdef UART_FIFO_WORKS
798 outportsb (port->base + com_data, str, cnt);
802 for ( ; cnt > 0; cnt--, len--)
803 outportb (port->base + com_data, *str++);
808 /* wait for transmission to complete (max 1 sec) */
809 then = rawclock () + RAWHZ;
812 if ((rawclock () - then) >= 0)
824 dos_sendbreak (serial_t scb)
826 volatile struct dos_ttystate *port = &ports[scb->fd];
830 cfcr = inb (port, com_cfcr);
831 outb (port, com_cfcr, cfcr | CFCR_SBREAK);
834 then = rawclock () + RAWHZ / 4;
835 while ((rawclock () - then) < 0)
838 outb (port, com_cfcr, cfcr);
843 static struct serial_ops dos_ops =
851 dos_noop, /* flush output */
858 dos_noflush_set_tty_state,
861 dos_noop, /* wait for output to drain */
862 (void (*)(serial_t, int))NULL /* change into async mode */
867 dos_info (char *arg ATTRIBUTE_UNUSED, int from_tty ATTRIBUTE_UNUSED)
869 struct dos_ttystate *port;
874 for (port = ports; port < &ports[4]; port++)
876 if (port->baudrate == 0)
878 printf_filtered ("Port:\tCOM%ld (%sactive)\n", (long)(port - ports) + 1,
879 port->intrupt ? "" : "not ");
880 printf_filtered ("Addr:\t0x%03x (irq %d)\n", port->base, port->irq);
881 printf_filtered ("16550:\t%s\n", port->fifo ? "yes" : "no");
882 printf_filtered ("Speed:\t%d baud\n", port->baudrate);
883 printf_filtered ("Errs:\tframing %d parity %d overflow %d\n\n",
884 port->ferr, port->perr, port->oflo);
888 printf_filtered ("\nTotal interrupts: %d\n", intrcnt);
889 for (i = 0; i < NCNT; i++)
891 printf_filtered ("%s:\t%d\n", cntnames[i], cnts[i]);
897 _initialize_ser_dos (void)
899 serial_add_interface (&dos_ops);
901 /* Save original interrupt mask register. */
902 icu_oldmask = inportb (ICU_MASK);
904 /* Mark fixed motherboard irqs as inuse. */
905 intrupts[0].inuse = /* timer tick */
906 intrupts[1].inuse = /* keyboard */
907 intrupts[2].inuse = 1; /* slave icu */
910 add_set_cmd ("com1base", class_obscure, var_zinteger,
911 (char *) &ports[0].base,
912 "Set COM1 base i/o port address.",
917 add_set_cmd ("com1irq", class_obscure, var_zinteger,
918 (char *) &ports[0].irq,
919 "Set COM1 interrupt request.",
924 add_set_cmd ("com2base", class_obscure, var_zinteger,
925 (char *) &ports[1].base,
926 "Set COM2 base i/o port address.",
931 add_set_cmd ("com2irq", class_obscure, var_zinteger,
932 (char *) &ports[1].irq,
933 "Set COM2 interrupt request.",
938 add_set_cmd ("com3base", class_obscure, var_zinteger,
939 (char *) &ports[2].base,
940 "Set COM3 base i/o port address.",
945 add_set_cmd ("com3irq", class_obscure, var_zinteger,
946 (char *) &ports[2].irq,
947 "Set COM3 interrupt request.",
952 add_set_cmd ("com4base", class_obscure, var_zinteger,
953 (char *) &ports[3].base,
954 "Set COM4 base i/o port address.",
959 add_set_cmd ("com4irq", class_obscure, var_zinteger,
960 (char *) &ports[3].irq,
961 "Set COM4 interrupt request.",
965 add_info ("serial", dos_info,
966 "Print DOS serial port status.");