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;
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));
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");
251 volatile struct dos_ttystate *port;
255 if (port->count == 0)
258 c = port->cbuf[port->first];
260 port->first = (port->first + 1) & (CBSIZE - 1);
270 struct dos_ttystate *port;
272 if (port->count >= CBSIZE - 1)
274 port->cbuf[(port->first + port->count) & (CBSIZE - 1)] = c;
285 struct dos_ttystate *port;
286 unsigned char iir, lsr, c;
288 disable (); /* Paranoia */
289 outportb (ICU_OCW2, 0x20); /* End-Of-Interrupt */
294 port = intrupts[irq].port;
298 return; /* not open */
303 iir = inb (port, com_iir) & IIR_IMASK;
308 lsr = inb (port, com_lsr);
318 c = inb (port, com_data);
319 if (lsr & (LSR_BI | LSR_FE | LSR_PE | LSR_OE))
321 if (lsr & (LSR_BI | LSR_FE))
323 else if (lsr & LSR_PE)
329 if (dos_putc (c, port) < 0)
338 while ((lsr = inb (port, com_lsr)) & LSR_RXRDY);
342 /* could be used to flowcontrol Tx */
343 port->msr = inb (port, com_msr);
351 /* no more pending interrupts, all done */
355 /* unexpected interrupt, ignore */
363 #define ISRNAME(x) dos_comisr##x
365 #define ISRNAME(x) dos_comisr/**/x
367 #define ISR(x) static void ISRNAME(x)() {dos_comisr(x);}
369 ISR (0) ISR (1) ISR (2) ISR (3)
370 ISR (4) ISR (5) ISR (6) ISR (7)
372 typedef void (*isr_t) ();
374 static isr_t isrs[NINTR] =
376 ISRNAME (0), ISRNAME (1), ISRNAME (2), ISRNAME (3),
377 ISRNAME (4), ISRNAME (5), ISRNAME (6), ISRNAME (7)
382 static struct intrupt *
386 struct intrupt *intr;
393 intr = &intrupts[irq];
400 /* setup real mode handler */
401 _go32_dpmi_get_real_mode_interrupt_vector (vec, &intr->old_rmhandler);
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,
411 if (_go32_dpmi_set_real_mode_interrupt_vector (vec, &intr->new_rmhandler))
416 /* setup protected mode handler */
417 _go32_dpmi_get_protected_mode_interrupt_vector (vec, &intr->old_pmhandler);
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);
423 if (_go32_dpmi_set_protected_mode_interrupt_vector (vec, &intr->new_pmhandler))
428 /* setup interrupt controller mask */
430 outportb (ICU_MASK, inportb (ICU_MASK) & ~(1 << irq));
440 struct intrupt *intr;
442 unsigned int irq, vec;
445 irq = intr - intrupts;
448 /* restore old interrupt mask bit */
451 outportb (ICU_MASK, inportb (ICU_MASK) | (mask & icu_oldmask));
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);
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);
471 struct dos_ttystate *port;
474 if (strncasecmp (name, "/dev/", 5) == 0)
476 else if (strncasecmp (name, "\\dev\\", 5) == 0)
479 if (strlen (name) != 4 || strncasecmp (name, "com", 3) != 0)
485 if (name[3] < '1' || name[3] > '4')
491 /* FIXME: this is a Bad Idea (tm)! One should *never* invent file
492 handles, since they might be already used by other files/devices.
493 The Right Way to do this is to create a real handle by dup()'ing
494 some existing one. */
497 if (port->refcnt++ > 0)
499 /* Device already opened another user. Just point at it. */
504 /* force access to ID reg */
505 outb (port, com_cfcr, 0);
506 outb (port, com_iir, 0);
507 for (i = 0; i < 17; i++)
509 if ((inb (port, com_iir) & 0x38) == 0)
511 (void) inb (port, com_data); /* clear recv */
517 /* disable all interrupts in chip */
518 outb (port, com_ier, 0);
520 /* tentatively enable 16550 fifo, and see if it responds */
521 outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER);
523 port->fifo = ((inb (port, com_iir) & IIR_FIFO_MASK) == IIR_FIFO_MASK);
525 /* clear pending status reports. */
526 (void) inb (port, com_lsr);
527 (void) inb (port, com_msr);
529 /* enable external interrupt gate (to avoid floating IRQ) */
530 outb (port, com_mcr, MCR_IENABLE);
532 /* hook up interrupt handler and initialise icu */
533 port->intrupt = dos_hookirq (port->irq);
536 outb (port, com_mcr, 0);
537 outb (port, com_fifo, 0);
545 port->intrupt->port = port;
548 /* clear rx buffer, tx busy flag and overflow count */
549 port->first = port->count = 0;
553 /* set default baud rate and mode: 9600,8,n,1 */
554 i = dos_baudconv (port->baudrate = 9600);
555 outb (port, com_cfcr, CFCR_DLAB);
556 outb (port, com_dlbl, i & 0xff);
557 outb (port, com_dlbh, i >> 8);
558 outb (port, com_cfcr, CFCR_8BITS);
560 /* enable all interrupts */
561 outb (port, com_ier, IER_ETXRDY | IER_ERXRDY | IER_ERLS | IER_EMSC);
563 /* enable DTR & RTS */
564 outb (port, com_mcr, MCR_DTR | MCR_RTS | MCR_IENABLE);
576 struct dos_ttystate *port;
577 struct intrupt *intrupt;
582 port = &ports[scb->fd];
584 if (port->refcnt-- > 1)
587 if (!(intrupt = port->intrupt))
590 /* disable interrupts, fifo, flow control */
594 outb (port, com_fifo, 0);
595 outb (port, com_ier, 0);
598 /* unhook handler, and disable interrupt gate */
599 dos_unhookirq (intrupt);
600 outb (port, com_mcr, 0);
602 /* Check for overflow errors */
605 fprintf_unfiltered (gdb_stderr,
606 "Serial input overruns occurred.\n");
607 fprintf_unfiltered (gdb_stderr, "This system %s handle %d baud.\n",
608 port->fifo ? "cannot" : "needs a 16550 to",
626 /* Always in raw mode */
630 dos_readchar (scb, timeout)
634 struct dos_ttystate *port = &ports[scb->fd];
638 then = rawclock () + (timeout * RAWHZ);
639 while ((c = dos_getc (port)) < 0)
641 if (timeout >= 0 && (rawclock () - then) >= 0)
642 return SERIAL_TIMEOUT;
650 static serial_ttystate
651 dos_get_tty_state (scb)
654 struct dos_ttystate *port = &ports[scb->fd];
655 struct dos_ttystate *state;
657 /* Are they asking about a port we opened? */
658 if (port->refcnt <= 0)
660 /* We've never heard about this port. We should fail this call,
661 unless they are asking about one of the 3 standard handles,
662 in which case we pretend the handle was open by us if it is
663 connected to a terminal device. This is beacuse Unix
664 terminals use the serial interface, so GDB expects the
665 standard handles to go through here. */
666 if (scb->fd >= 3 || !isatty (scb->fd))
670 state = (struct dos_ttystate *) xmalloc (sizeof *state);
672 return (serial_ttystate) state;
676 dos_set_tty_state (scb, ttystate)
678 serial_ttystate ttystate;
680 struct dos_ttystate *state;
682 state = (struct dos_ttystate *) ttystate;
683 dos_setbaudrate (scb, state->baudrate);
688 dos_noflush_set_tty_state (scb, new_ttystate, old_ttystate)
690 serial_ttystate new_ttystate;
691 serial_ttystate old_ttystate;
693 struct dos_ttystate *state;
695 state = (struct dos_ttystate *) new_ttystate;
696 dos_setbaudrate (scb, state->baudrate);
701 dos_flush_input (scb)
704 struct dos_ttystate *port = &ports[scb->fd];
706 port->first = port->count = 0;
708 outb (port, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_TRIGGER);
714 dos_print_tty_state (serial_t scb,
715 serial_ttystate ttystate,
716 struct ui_file *stream)
718 /* Nothing to print */
731 #define divrnd(n, q) (((n) * 2 / (q) + 1) / 2) /* divide and round off */
732 x = divrnd (COMTICK, rate);
736 err = divrnd (1000 * COMTICK, x * rate) - 1000;
739 if (err > SPEED_TOLERANCE)
747 dos_setbaudrate (scb, rate)
751 struct dos_ttystate *port = &ports[scb->fd];
753 if (port->baudrate != rate)
758 x = dos_baudconv (rate);
761 fprintf_unfiltered (gdb_stderr, "%d: impossible baudrate\n", rate);
767 cfcr = inb (port, com_cfcr);
769 outb (port, com_cfcr, CFCR_DLAB);
770 outb (port, com_dlbl, x & 0xff);
771 outb (port, com_dlbh, x >> 8);
772 outb (port, com_cfcr, cfcr);
773 port->baudrate = rate;
781 dos_setstopbits (scb, num)
785 struct dos_ttystate *port = &ports[scb->fd];
789 cfcr = inb (port, com_cfcr);
793 case SERIAL_1_STOPBITS:
794 outb (port, com_cfcr, cfcr & ~CFCR_STOPB);
796 case SERIAL_1_AND_A_HALF_STOPBITS:
797 case SERIAL_2_STOPBITS:
798 outb (port, com_cfcr, cfcr | CFCR_STOPB);
810 dos_write (scb, str, len)
815 volatile struct dos_ttystate *port = &ports[scb->fd];
816 int fifosize = port->fifo ? 16 : 1;
822 /* send the data, fifosize bytes at a time */
823 cnt = fifosize > len ? len : fifosize;
825 outportsb (port->base + com_data, str, cnt);
831 /* wait for transmission to complete (max 1 sec) */
832 then = rawclock () + RAWHZ;
835 if ((rawclock () - then) >= 0)
850 volatile struct dos_ttystate *port = &ports[scb->fd];
854 cfcr = inb (port, com_cfcr);
855 outb (port, com_cfcr, cfcr | CFCR_SBREAK);
858 then = rawclock () + RAWHZ / 4;
859 while ((rawclock () - then) < 0)
862 outb (port, com_cfcr, cfcr);
867 static struct serial_ops dos_ops =
875 dos_noop, /* flush output */
882 dos_noflush_set_tty_state,
885 dos_noop, /* wait for output to drain */
890 dos_info (arg, from_tty)
894 struct dos_ttystate *port;
897 for (port = ports; port < &ports[4]; port++)
899 if (port->baudrate == 0)
901 printf_filtered ("Port:\tCOM%d (%sactive)\n", port - ports + 1,
902 port->intrupt ? "" : "not ");
903 printf_filtered ("Addr:\t0x%03x (irq %d)\n", port->base, port->irq);
904 printf_filtered ("16550:\t%s\n", port->fifo ? "yes" : "no");
905 printf_filtered ("Speed:\t%d baud\n", port->baudrate);
906 printf_filtered ("Errs:\tframing %d parity %d overflow %d\n\n",
907 port->ferr, port->perr, port->oflo);
911 printf_filtered ("\nTotal interrupts: %d\n", intrcnt);
912 for (i = 0; i < NCNT; i++)
914 printf_filtered ("%s:\t%d\n", cntnames[i], cnts[i]);
920 _initialize_ser_dos ()
922 struct cmd_list_element *c;
924 serial_add_interface (&dos_ops);
926 /* Save original interrupt mask register. */
927 icu_oldmask = inportb (ICU_MASK);
929 /* Mark fixed motherboard irqs as inuse. */
930 intrupts[0].inuse = /* timer tick */
931 intrupts[1].inuse = /* keyboard */
932 intrupts[2].inuse = 1; /* slave icu */
935 add_set_cmd ("com1base", class_obscure, var_zinteger,
936 (char *) &ports[0].base,
937 "Set COM1 base i/o port address.",
942 add_set_cmd ("com1irq", class_obscure, var_zinteger,
943 (char *) &ports[0].irq,
944 "Set COM1 interrupt request.",
949 add_set_cmd ("com2base", class_obscure, var_zinteger,
950 (char *) &ports[1].base,
951 "Set COM2 base i/o port address.",
956 add_set_cmd ("com2irq", class_obscure, var_zinteger,
957 (char *) &ports[1].irq,
958 "Set COM2 interrupt request.",
963 add_set_cmd ("com3base", class_obscure, var_zinteger,
964 (char *) &ports[2].base,
965 "Set COM3 base i/o port address.",
970 add_set_cmd ("com3irq", class_obscure, var_zinteger,
971 (char *) &ports[2].irq,
972 "Set COM3 interrupt request.",
977 add_set_cmd ("com4base", class_obscure, var_zinteger,
978 (char *) &ports[3].base,
979 "Set COM4 base i/o port address.",
984 add_set_cmd ("com4irq", class_obscure, var_zinteger,
985 (char *) &ports[3].irq,
986 "Set COM4 interrupt request.",
990 add_info ("serial", dos_info,
991 "Print DOS serial port status.");