1 /* Remote serial interface for local (hardwired) serial ports for
2 GO32. Copyright 1992, 1993 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, Boston, MA 02111-1307, USA. */
31 * NS16550 UART registers
34 #define COM1ADDR 0x3f8
35 #define COM2ADDR 0x2f8
36 #define COM3ADDR 0x3e8
37 #define COM4ADDR 0x3e0
39 #define com_data 0 /* data register (R/W) */
40 #define com_dlbl 0 /* divisor latch low (W) */
41 #define com_ier 1 /* interrupt enable (W) */
42 #define com_dlbh 1 /* divisor latch high (W) */
43 #define com_iir 2 /* interrupt identification (R) */
44 #define com_fifo 2 /* FIFO control (W) */
45 #define com_lctl 3 /* line control register (R/W) */
46 #define com_cfcr 3 /* line control register (R/W) */
47 #define com_mcr 4 /* modem control register (R/W) */
48 #define com_lsr 5 /* line status register (R/W) */
49 #define com_msr 6 /* modem status register (R/W) */
52 * Constants for computing 16 bit baud rate divisor (lower byte
53 * in com_dlbl, upper in com_dlbh) from 1.8432MHz crystal. Divisor is
54 * 1.8432 MHz / (16 * X) for X bps. If the baud rate can't be set
55 * to within +- (desired_rate*SPEED_TOLERANCE/1000) bps, we fail.
57 #define COMTICK (1843200/16)
58 #define SPEED_TOLERANCE 30 /* thousandths; real == desired +- 3.0% */
60 /* interrupt enable register */
61 #define IER_ERXRDY 0x1 /* int on rx ready */
62 #define IER_ETXRDY 0x2 /* int on tx ready */
63 #define IER_ERLS 0x4 /* int on line status change */
64 #define IER_EMSC 0x8 /* int on modem status change */
66 /* interrupt identification register */
67 #define IIR_FIFO_MASK 0xc0 /* set if FIFOs are enabled */
68 #define IIR_IMASK 0xf /* interrupt cause mask */
69 #define IIR_NOPEND 0x1 /* nothing pending */
70 #define IIR_RLS 0x6 /* receive line status */
71 #define IIR_RXRDY 0x4 /* receive ready */
72 #define IIR_RXTOUT 0xc /* receive timeout */
73 #define IIR_TXRDY 0x2 /* transmit ready */
74 #define IIR_MLSC 0x0 /* modem status */
77 /* fifo control register */
78 #define FIFO_ENABLE 0x01 /* enable fifo */
79 #define FIFO_RCV_RST 0x02 /* reset receive fifo */
80 #define FIFO_XMT_RST 0x04 /* reset transmit fifo */
81 #define FIFO_DMA_MODE 0x08 /* enable dma mode */
82 #define FIFO_TRIGGER_1 0x00 /* trigger at 1 char */
83 #define FIFO_TRIGGER_4 0x40 /* trigger at 4 chars */
84 #define FIFO_TRIGGER_8 0x80 /* trigger at 8 chars */
85 #define FIFO_TRIGGER_14 0xc0 /* trigger at 14 chars */
87 /* character format control register */
88 #define CFCR_DLAB 0x80 /* divisor latch */
89 #define CFCR_SBREAK 0x40 /* send break */
90 #define CFCR_PZERO 0x30 /* zero parity */
91 #define CFCR_PONE 0x20 /* one parity */
92 #define CFCR_PEVEN 0x10 /* even parity */
93 #define CFCR_PODD 0x00 /* odd parity */
94 #define CFCR_PENAB 0x08 /* parity enable */
95 #define CFCR_STOPB 0x04 /* 2 stop bits */
96 #define CFCR_8BITS 0x03 /* 8 data bits */
97 #define CFCR_7BITS 0x02 /* 7 data bits */
98 #define CFCR_6BITS 0x01 /* 6 data bits */
99 #define CFCR_5BITS 0x00 /* 5 data bits */
101 /* modem control register */
102 #define MCR_LOOPBACK 0x10 /* loopback */
103 #define MCR_IENABLE 0x08 /* output 2 = int enable */
104 #define MCR_DRS 0x04 /* output 1 = xxx */
105 #define MCR_RTS 0x02 /* enable RTS */
106 #define MCR_DTR 0x01 /* enable DTR */
108 /* line status register */
109 #define LSR_RCV_FIFO 0x80 /* error in receive fifo */
110 #define LSR_TSRE 0x40 /* transmitter empty */
111 #define LSR_TXRDY 0x20 /* transmitter ready */
112 #define LSR_BI 0x10 /* break detected */
113 #define LSR_FE 0x08 /* framing error */
114 #define LSR_PE 0x04 /* parity error */
115 #define LSR_OE 0x02 /* overrun error */
116 #define LSR_RXRDY 0x01 /* receiver ready */
117 #define LSR_RCV_MASK 0x1f
119 /* modem status register */
124 #define MSR_DDCD 0x08
125 #define MSR_TERI 0x04
126 #define MSR_DDSR 0x02
127 #define MSR_DCTS 0x01
132 typedef unsigned long u_long
;
134 /* DPMI Communication */
135 static union REGS dpmi_regs
;
136 static struct SREGS dpmi_sregs
;
138 /* 16550 rx fifo trigger point */
139 #define FIFO_TRIGGER FIFO_TRIGGER_4
141 /* input buffer size */
144 /* return raw 18Hz clock count */
145 extern long rawclock (void);
157 static int cnts
[NCNT
];
158 static char *cntnames
[NCNT
] = {
159 /* h/w interrupt counts. */
160 "mlsc", "nopend", "txrdy", "?3",
161 "rxrdy", "?5", "rls", "?7",
162 "?8", "?9", "?a", "?b",
163 "rxtout", "?d", "?e", "?f",
165 "rxcnt", "txcnt", "stray", "swoflo"
168 #define COUNT(x) cnts[x]++
173 /* Main interrupt controller port addresses. */
174 #define ICU_BASE 0x20
175 #define ICU_OCW2 (ICU_BASE + 0)
176 #define ICU_MASK (ICU_BASE + 1)
178 /* Original interrupt controller mask register. */
179 unsigned char icu_oldmask
;
181 /* Maximum of 8 interrupts (we don't handle the slave icu yet). */
184 static struct intrupt
187 struct dos_ttystate
*port
;
188 _go32_dpmi_seginfo old_rmhandler
;
189 _go32_dpmi_seginfo old_pmhandler
;
190 _go32_dpmi_seginfo new_rmhandler
;
191 _go32_dpmi_seginfo new_pmhandler
;
192 _go32_dpmi_registers regs
;
196 static struct dos_ttystate
201 struct intrupt
*intrupt
;
204 unsigned char cbuf
[CBSIZE
];
208 unsigned char old_mcr
;
220 static int dos_open
PARAMS ((serial_t scb
, const char *name
));
221 static void dos_raw
PARAMS ((serial_t scb
));
222 static int dos_readchar
PARAMS ((serial_t scb
, int timeout
));
223 static int dos_setbaudrate
PARAMS ((serial_t scb
, int rate
));
224 static int dos_write
PARAMS ((serial_t scb
, const char *str
, int len
));
225 static void dos_close
PARAMS ((serial_t scb
));
226 static serial_ttystate dos_get_tty_state
PARAMS ((serial_t scb
));
227 static int dos_set_tty_state
PARAMS ((serial_t scb
, serial_ttystate state
));
228 static int dos_baudconv
PARAMS ((int rate
));
230 #define inb(p,a) inportb((p)->base + (a))
231 #define outb(p,a,v) outportb((p)->base + (a), (v))
232 #define disable() asm volatile ("cli");
233 #define enable() asm volatile ("sti");
238 volatile struct dos_ttystate
*port
;
242 if (port
->count
== 0)
245 c
= port
->cbuf
[port
->first
];
247 port
->first
= (port
->first
+ 1) & (CBSIZE
- 1);
257 struct dos_ttystate
*port
;
259 if (port
->count
>= CBSIZE
- 1)
261 port
->cbuf
[(port
->first
+ port
->count
) & (CBSIZE
- 1)] = c
;
272 struct dos_ttystate
*port
;
273 unsigned char iir
, lsr
, c
;
275 disable (); /* Paranoia */
276 outportb (ICU_OCW2
, 0x20); /* End-Of-Interrupt */
281 port
= intrupts
[irq
].port
;
285 return; /* not open */
290 iir
= inb (port
, com_iir
) & IIR_IMASK
;
295 lsr
= inb (port
, com_lsr
);
305 c
= inb (port
, com_data
);
306 if (lsr
& (LSR_BI
| LSR_FE
| LSR_PE
| LSR_OE
))
308 if (lsr
& (LSR_BI
| LSR_FE
))
310 else if (lsr
& LSR_PE
)
316 if (dos_putc (c
, port
) < 0)
325 while ((lsr
= inb (port
, com_lsr
)) & LSR_RXRDY
);
329 /* could be used to flowcontrol Tx */
330 port
->msr
= inb (port
, com_msr
);
338 /* no more pending interrupts, all done */
342 /* unexpected interrupt, ignore */
350 #define ISRNAME(x) dos_comisr##x
352 #define ISRNAME(x) dos_comisr/**/x
354 #define ISR(x) static void ISRNAME(x)() {dos_comisr(x);}
356 ISR(0) ISR(1) ISR(2) ISR(3)
357 ISR(4) ISR(5) ISR(6) ISR(7)
359 typedef void (*isr_t
)();
361 static isr_t isrs
[NINTR
] = {
362 ISRNAME(0), ISRNAME(1), ISRNAME(2), ISRNAME(3),
363 ISRNAME(4), ISRNAME(5), ISRNAME(6), ISRNAME(7)
368 static struct intrupt
*
372 struct intrupt
*intr
;
379 intr
= &intrupts
[irq
];
386 /* setup real mode handler */
387 _go32_dpmi_get_real_mode_interrupt_vector (vec
, &intr
->old_rmhandler
);
389 intr
->new_rmhandler
.pm_selector
= _go32_my_cs();
390 intr
->new_rmhandler
.pm_offset
= (u_long
)isr
;
391 if (_go32_dpmi_allocate_real_mode_callback_iret (&intr
->new_rmhandler
,
397 if (_go32_dpmi_set_real_mode_interrupt_vector (vec
, &intr
->new_rmhandler
))
402 /* setup protected mode handler */
403 _go32_dpmi_get_protected_mode_interrupt_vector(vec
, &intr
->old_pmhandler
);
405 intr
->new_pmhandler
.pm_selector
= _go32_my_cs();
406 intr
->new_pmhandler
.pm_offset
= (u_long
)isr
;
407 _go32_dpmi_allocate_iret_wrapper (&intr
->new_pmhandler
);
409 if (_go32_dpmi_set_protected_mode_interrupt_vector(vec
, &intr
->new_pmhandler
))
414 /* setup interrupt controller mask */
416 outportb (ICU_MASK
, inportb (ICU_MASK
) & ~(1 << irq
));
426 struct intrupt
*intr
;
428 unsigned int irq
, vec
;
431 irq
= intr
- intrupts
;
434 /* restore old interrupt mask bit */
437 outportb (ICU_MASK
, inportb (ICU_MASK
) | (mask
& icu_oldmask
));
440 /* remove real mode handler */
441 _go32_dpmi_set_real_mode_interrupt_vector (vec
, &intr
->old_rmhandler
);
442 _go32_dpmi_free_real_mode_callback (&intr
->new_rmhandler
);
444 /* remove protected mode handler */
445 _go32_dpmi_set_protected_mode_interrupt_vector (vec
, &intr
->old_pmhandler
);
446 _go32_dpmi_free_iret_wrapper (&intr
->new_pmhandler
);
457 struct dos_ttystate
*port
;
460 if (strncasecmp (name
, "/dev/", 5) == 0)
462 else if (strncasecmp (name
, "\\dev\\", 5) == 0)
465 if (strlen (name
) != 4 || strncasecmp (name
, "com", 3) != 0)
471 if (name
[3] < '1' || name
[3] > '4')
479 if (port
->refcnt
++ > 0)
481 /* Device already opened another user. Just point at it. */
486 /* force access to ID reg */
487 outb(port
, com_cfcr
, 0);
488 outb(port
, com_iir
, 0);
489 for (i
= 0; i
< 17; i
++) {
490 if ((inb(port
, com_iir
) & 0x38) == 0)
492 (void) inb(port
, com_data
); /* clear recv */
498 /* disable all interrupts in chip */
499 outb(port
, com_ier
, 0);
501 /* tentatively enable 16550 fifo, and see if it responds */
502 outb(port
, com_fifo
, FIFO_ENABLE
|FIFO_RCV_RST
|FIFO_XMT_RST
|FIFO_TRIGGER
);
504 port
->fifo
= ((inb(port
, com_iir
) & IIR_FIFO_MASK
) == IIR_FIFO_MASK
);
506 /* clear pending status reports. */
507 (void) inb(port
, com_lsr
);
508 (void) inb(port
, com_msr
);
510 /* enable external interrupt gate (to avoid floating IRQ) */
511 outb(port
, com_mcr
, MCR_IENABLE
);
513 /* hook up interrupt handler and initialise icu */
514 port
->intrupt
= dos_hookirq (port
->irq
);
517 outb(port
, com_mcr
, 0);
518 outb(port
, com_fifo
, 0);
526 port
->intrupt
->port
= port
;
529 /* clear rx buffer, tx busy flag and overflow count */
530 port
->first
= port
->count
= 0;
534 /* set default baud rate and mode: 9600,8,n,1 */
535 i
= dos_baudconv (port
->baudrate
= 9600);
536 outb(port
, com_cfcr
, CFCR_DLAB
);
537 outb(port
, com_dlbl
, i
& 0xff);
538 outb(port
, com_dlbh
, i
>> 8);
539 outb(port
, com_cfcr
, CFCR_8BITS
);
541 /* enable all interrupts */
542 outb(port
, com_ier
, IER_ETXRDY
| IER_ERXRDY
| IER_ERLS
| IER_EMSC
);
544 /* enable DTR & RTS */
545 outb(port
, com_mcr
, MCR_DTR
| MCR_RTS
| MCR_IENABLE
);
557 struct dos_ttystate
*port
;
558 struct intrupt
*intrupt
;
563 port
= &ports
[scb
->fd
];
565 if (port
->refcnt
-- > 1)
568 if (!(intrupt
= port
->intrupt
))
571 /* disable interrupts, fifo, flow control */
575 outb(port
, com_fifo
, 0);
576 outb(port
, com_ier
, 0);
579 /* unhook handler, and disable interrupt gate */
580 dos_unhookirq (intrupt
);
581 outb(port
, com_mcr
, 0);
583 /* Check for overflow errors */
586 fprintf_unfiltered (gdb_stderr
,
587 "Serial input overruns occurred.\n");
588 fprintf_unfiltered (gdb_stderr
, "This system %s handle %d baud.\n",
589 port
->fifo
? "cannot" : "needs a 16550 to",
607 /* Always in raw mode */
611 dos_readchar (scb
, timeout
)
615 struct dos_ttystate
*port
= &ports
[scb
->fd
];
619 then
= rawclock() + (timeout
* RAWHZ
);
620 while ((c
= dos_getc (port
)) < 0)
622 if (timeout
>= 0 && (rawclock () - then
) >= 0)
623 return SERIAL_TIMEOUT
;
631 static serial_ttystate
632 dos_get_tty_state (scb
)
635 struct dos_ttystate
*port
= &ports
[scb
->fd
];
636 struct dos_ttystate
*state
;
638 state
= (struct dos_ttystate
*) xmalloc (sizeof *state
);
640 return (serial_ttystate
) state
;
644 dos_set_tty_state (scb
, ttystate
)
646 serial_ttystate ttystate
;
648 struct dos_ttystate
*state
;
650 state
= (struct dos_ttystate
*) ttystate
;
651 dos_setbaudrate (scb
, state
->baudrate
);
656 dos_noflush_set_tty_state (scb
, new_ttystate
, old_ttystate
)
658 serial_ttystate new_ttystate
;
659 serial_ttystate old_ttystate
;
661 struct dos_ttystate
*state
;
663 state
= (struct dos_ttystate
*) new_ttystate
;
664 dos_setbaudrate (scb
, state
->baudrate
);
669 dos_flush_input (scb
)
672 struct dos_ttystate
*port
= &ports
[scb
->fd
];
674 port
->first
= port
->count
= 0;
676 outb(port
, com_fifo
, FIFO_ENABLE
|FIFO_RCV_RST
|FIFO_TRIGGER
);
681 dos_print_tty_state (scb
, ttystate
)
683 serial_ttystate ttystate
;
685 /* Nothing to print */
698 #define divrnd(n, q) (((n) * 2 / (q) + 1) / 2) /* divide and round off */
699 x
= divrnd(COMTICK
, rate
);
703 err
= divrnd(1000 * COMTICK
, x
* rate
) - 1000;
706 if (err
> SPEED_TOLERANCE
)
714 dos_setbaudrate (scb
, rate
)
718 struct dos_ttystate
*port
= &ports
[scb
->fd
];
720 if (port
->baudrate
!= rate
)
725 x
= dos_baudconv (rate
);
728 fprintf_unfiltered (gdb_stderr
, "%d: impossible baudrate\n", rate
);
734 cfcr
= inb (port
, com_cfcr
);
736 outb(port
, com_cfcr
, CFCR_DLAB
);
737 outb(port
, com_dlbl
, x
& 0xff);
738 outb(port
, com_dlbh
, x
>> 8);
739 outb(port
, com_cfcr
, cfcr
);
740 port
->baudrate
= rate
;
748 dos_setstopbits (scb
, num
)
752 struct dos_ttystate
*port
= &ports
[scb
->fd
];
756 cfcr
= inb (port
, com_cfcr
);
760 case SERIAL_1_STOPBITS
:
761 outb (port
, com_cfcr
, cfcr
& ~CFCR_STOPB
);
763 case SERIAL_1_AND_A_HALF_STOPBITS
:
764 case SERIAL_2_STOPBITS
:
765 outb (port
, com_cfcr
, cfcr
| CFCR_STOPB
);
777 dos_write (scb
, str
, len
)
782 volatile struct dos_ttystate
*port
= &ports
[scb
->fd
];
783 int fifosize
= port
->fifo
? 16 : 1;
789 /* send the data, fifosize bytes at a time */
790 cnt
= fifosize
> len
? len
: fifosize
;
792 outportsb (port
->base
+ com_data
, str
, cnt
);
798 /* wait for transmission to complete (max 1 sec) */
799 then
= rawclock() + RAWHZ
;
802 if ((rawclock () - then
) >= 0)
817 volatile struct dos_ttystate
*port
= &ports
[scb
->fd
];
821 cfcr
= inb(port
, com_cfcr
);
822 outb(port
, com_cfcr
, cfcr
| CFCR_SBREAK
);
825 then
= rawclock () + RAWHZ
/ 4;
826 while ((rawclock () - then
) < 0)
829 outb(port
, com_cfcr
, cfcr
);
834 static struct serial_ops dos_ops
=
842 dos_noop
, /* flush output */
849 dos_noflush_set_tty_state
,
852 dos_noop
, /* wait for output to drain */
857 dos_info (arg
, from_tty
)
861 struct dos_ttystate
*port
;
864 for (port
= ports
; port
< &ports
[4]; port
++)
866 if (port
->baudrate
== 0)
868 printf_filtered ("Port:\tCOM%d (%sactive)\n", port
- ports
+ 1,
869 port
->intrupt
? "" : "not ");
870 printf_filtered ("Addr:\t0x%03x (irq %d)\n", port
->base
, port
->irq
);
871 printf_filtered ("16550:\t%s\n", port
->fifo
? "yes" : "no");
872 printf_filtered ("Speed:\t%d baud\n", port
->baudrate
);
873 printf_filtered ("Errs:\tframing %d parity %d overflow %d\n\n",
874 port
->ferr
, port
->perr
, port
->oflo
);
878 printf_filtered ("\nTotal interrupts: %d\n", intrcnt
);
879 for (i
= 0; i
< NCNT
; i
++)
881 printf_filtered ("%s:\t%d\n", cntnames
[i
], cnts
[i
]);
887 _initialize_ser_dos ()
889 struct cmd_list_element
*c
;
891 serial_add_interface (&dos_ops
);
893 /* Save original interrupt mask register. */
894 icu_oldmask
= inportb (ICU_MASK
);
896 /* Mark fixed motherboard irqs as inuse. */
897 intrupts
[0].inuse
= /* timer tick */
898 intrupts
[1].inuse
= /* keyboard */
899 intrupts
[2].inuse
= 1; /* slave icu */
902 add_set_cmd ("com1base", class_obscure
, var_zinteger
,
903 (char *) &ports
[0].base
,
904 "Set COM1 base i/o port address.",
909 add_set_cmd ("com1irq", class_obscure
, var_zinteger
,
910 (char *) &ports
[0].irq
,
911 "Set COM1 interrupt request.",
916 add_set_cmd ("com2base", class_obscure
, var_zinteger
,
917 (char *) &ports
[1].base
,
918 "Set COM2 base i/o port address.",
923 add_set_cmd ("com2irq", class_obscure
, var_zinteger
,
924 (char *) &ports
[1].irq
,
925 "Set COM2 interrupt request.",
930 add_set_cmd ("com3base", class_obscure
, var_zinteger
,
931 (char *) &ports
[2].base
,
932 "Set COM3 base i/o port address.",
937 add_set_cmd ("com3irq", class_obscure
, var_zinteger
,
938 (char *) &ports
[2].irq
,
939 "Set COM3 interrupt request.",
944 add_set_cmd ("com4base", class_obscure
, var_zinteger
,
945 (char *) &ports
[3].base
,
946 "Set COM4 base i/o port address.",
951 add_set_cmd ("com4irq", class_obscure
, var_zinteger
,
952 (char *) &ports
[3].irq
,
953 "Set COM4 interrupt request.",
957 add_info ("serial", dos_info
,
958 "Print DOS serial port status.");