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,
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
133 typedef unsigned long u_long
;
135 /* DPMI Communication */
136 static union REGS dpmi_regs
;
137 static struct SREGS dpmi_sregs
;
139 /* 16550 rx fifo trigger point */
140 #define FIFO_TRIGGER FIFO_TRIGGER_4
142 /* input buffer size */
145 /* return raw 18Hz clock count */
146 extern long rawclock (void);
158 static int cnts
[NCNT
];
159 static char *cntnames
[NCNT
] =
161 /* h/w interrupt counts. */
162 "mlsc", "nopend", "txrdy", "?3",
163 "rxrdy", "?5", "rls", "?7",
164 "?8", "?9", "?a", "?b",
165 "rxtout", "?d", "?e", "?f",
167 "rxcnt", "txcnt", "stray", "swoflo"
170 #define COUNT(x) cnts[x]++
175 /* Main interrupt controller port addresses. */
176 #define ICU_BASE 0x20
177 #define ICU_OCW2 (ICU_BASE + 0)
178 #define ICU_MASK (ICU_BASE + 1)
180 /* Original interrupt controller mask register. */
181 unsigned char icu_oldmask
;
183 /* Maximum of 8 interrupts (we don't handle the slave icu yet). */
186 static struct intrupt
189 struct dos_ttystate
*port
;
190 _go32_dpmi_seginfo old_rmhandler
;
191 _go32_dpmi_seginfo old_pmhandler
;
192 _go32_dpmi_seginfo new_rmhandler
;
193 _go32_dpmi_seginfo new_pmhandler
;
194 _go32_dpmi_registers regs
;
199 static struct dos_ttystate
204 struct intrupt
*intrupt
;
207 unsigned char cbuf
[CBSIZE
];
211 unsigned char old_mcr
;
236 static int dos_open
PARAMS ((serial_t scb
, const char *name
));
237 static void dos_raw
PARAMS ((serial_t scb
));
238 static int dos_readchar
PARAMS ((serial_t scb
, int timeout
));
239 static int dos_setbaudrate
PARAMS ((serial_t scb
, int rate
));
240 static int dos_write
PARAMS ((serial_t scb
, const char *str
, int len
));
241 static void dos_close
PARAMS ((serial_t scb
));
242 static serial_ttystate dos_get_tty_state
PARAMS ((serial_t scb
));
243 static int dos_set_tty_state
PARAMS ((serial_t scb
, serial_ttystate state
));
244 static int dos_baudconv
PARAMS ((int rate
));
246 #define inb(p,a) inportb((p)->base + (a))
247 #define outb(p,a,v) outportb((p)->base + (a), (v))
248 #define disable() asm volatile ("cli");
249 #define enable() asm volatile ("sti");
254 volatile struct dos_ttystate
*port
;
258 if (port
->count
== 0)
261 c
= port
->cbuf
[port
->first
];
263 port
->first
= (port
->first
+ 1) & (CBSIZE
- 1);
273 struct dos_ttystate
*port
;
275 if (port
->count
>= CBSIZE
- 1)
277 port
->cbuf
[(port
->first
+ port
->count
) & (CBSIZE
- 1)] = c
;
288 struct dos_ttystate
*port
;
289 unsigned char iir
, lsr
, c
;
291 disable (); /* Paranoia */
292 outportb (ICU_OCW2
, 0x20); /* End-Of-Interrupt */
297 port
= intrupts
[irq
].port
;
301 return; /* not open */
306 iir
= inb (port
, com_iir
) & IIR_IMASK
;
311 lsr
= inb (port
, com_lsr
);
321 c
= inb (port
, com_data
);
322 if (lsr
& (LSR_BI
| LSR_FE
| LSR_PE
| LSR_OE
))
324 if (lsr
& (LSR_BI
| LSR_FE
))
326 else if (lsr
& LSR_PE
)
332 if (dos_putc (c
, port
) < 0)
341 while ((lsr
= inb (port
, com_lsr
)) & LSR_RXRDY
);
345 /* could be used to flowcontrol Tx */
346 port
->msr
= inb (port
, com_msr
);
354 /* no more pending interrupts, all done */
358 /* unexpected interrupt, ignore */
366 #define ISRNAME(x) dos_comisr##x
368 #define ISRNAME(x) dos_comisr/**/x
370 #define ISR(x) static void ISRNAME(x)() {dos_comisr(x);}
372 ISR (0) ISR (1) ISR (2) ISR (3)
373 ISR (4) ISR (5) ISR (6) ISR (7)
375 typedef void (*isr_t
) ();
377 static isr_t isrs
[NINTR
] =
379 ISRNAME (0), ISRNAME (1), ISRNAME (2), ISRNAME (3),
380 ISRNAME (4), ISRNAME (5), ISRNAME (6), ISRNAME (7)
385 static struct intrupt
*
389 struct intrupt
*intr
;
396 intr
= &intrupts
[irq
];
403 /* setup real mode handler */
404 _go32_dpmi_get_real_mode_interrupt_vector (vec
, &intr
->old_rmhandler
);
406 intr
->new_rmhandler
.pm_selector
= _go32_my_cs ();
407 intr
->new_rmhandler
.pm_offset
= (u_long
) isr
;
408 if (_go32_dpmi_allocate_real_mode_callback_iret (&intr
->new_rmhandler
,
414 if (_go32_dpmi_set_real_mode_interrupt_vector (vec
, &intr
->new_rmhandler
))
419 /* setup protected mode handler */
420 _go32_dpmi_get_protected_mode_interrupt_vector (vec
, &intr
->old_pmhandler
);
422 intr
->new_pmhandler
.pm_selector
= _go32_my_cs ();
423 intr
->new_pmhandler
.pm_offset
= (u_long
) isr
;
424 _go32_dpmi_allocate_iret_wrapper (&intr
->new_pmhandler
);
426 if (_go32_dpmi_set_protected_mode_interrupt_vector (vec
, &intr
->new_pmhandler
))
431 /* setup interrupt controller mask */
433 outportb (ICU_MASK
, inportb (ICU_MASK
) & ~(1 << irq
));
443 struct intrupt
*intr
;
445 unsigned int irq
, vec
;
448 irq
= intr
- intrupts
;
451 /* restore old interrupt mask bit */
454 outportb (ICU_MASK
, inportb (ICU_MASK
) | (mask
& icu_oldmask
));
457 /* remove real mode handler */
458 _go32_dpmi_set_real_mode_interrupt_vector (vec
, &intr
->old_rmhandler
);
459 _go32_dpmi_free_real_mode_callback (&intr
->new_rmhandler
);
461 /* remove protected mode handler */
462 _go32_dpmi_set_protected_mode_interrupt_vector (vec
, &intr
->old_pmhandler
);
463 _go32_dpmi_free_iret_wrapper (&intr
->new_pmhandler
);
474 struct dos_ttystate
*port
;
477 if (strncasecmp (name
, "/dev/", 5) == 0)
479 else if (strncasecmp (name
, "\\dev\\", 5) == 0)
482 if (strlen (name
) != 4 || strncasecmp (name
, "com", 3) != 0)
488 if (name
[3] < '1' || name
[3] > '4')
496 if (port
->refcnt
++ > 0)
498 /* Device already opened another user. Just point at it. */
503 /* force access to ID reg */
504 outb (port
, com_cfcr
, 0);
505 outb (port
, com_iir
, 0);
506 for (i
= 0; i
< 17; i
++)
508 if ((inb (port
, com_iir
) & 0x38) == 0)
510 (void) inb (port
, com_data
); /* clear recv */
516 /* disable all interrupts in chip */
517 outb (port
, com_ier
, 0);
519 /* tentatively enable 16550 fifo, and see if it responds */
520 outb (port
, com_fifo
, FIFO_ENABLE
| FIFO_RCV_RST
| FIFO_XMT_RST
| FIFO_TRIGGER
);
522 port
->fifo
= ((inb (port
, com_iir
) & IIR_FIFO_MASK
) == IIR_FIFO_MASK
);
524 /* clear pending status reports. */
525 (void) inb (port
, com_lsr
);
526 (void) inb (port
, com_msr
);
528 /* enable external interrupt gate (to avoid floating IRQ) */
529 outb (port
, com_mcr
, MCR_IENABLE
);
531 /* hook up interrupt handler and initialise icu */
532 port
->intrupt
= dos_hookirq (port
->irq
);
535 outb (port
, com_mcr
, 0);
536 outb (port
, com_fifo
, 0);
544 port
->intrupt
->port
= port
;
547 /* clear rx buffer, tx busy flag and overflow count */
548 port
->first
= port
->count
= 0;
552 /* set default baud rate and mode: 9600,8,n,1 */
553 i
= dos_baudconv (port
->baudrate
= 9600);
554 outb (port
, com_cfcr
, CFCR_DLAB
);
555 outb (port
, com_dlbl
, i
& 0xff);
556 outb (port
, com_dlbh
, i
>> 8);
557 outb (port
, com_cfcr
, CFCR_8BITS
);
559 /* enable all interrupts */
560 outb (port
, com_ier
, IER_ETXRDY
| IER_ERXRDY
| IER_ERLS
| IER_EMSC
);
562 /* enable DTR & RTS */
563 outb (port
, com_mcr
, MCR_DTR
| MCR_RTS
| MCR_IENABLE
);
575 struct dos_ttystate
*port
;
576 struct intrupt
*intrupt
;
581 port
= &ports
[scb
->fd
];
583 if (port
->refcnt
-- > 1)
586 if (!(intrupt
= port
->intrupt
))
589 /* disable interrupts, fifo, flow control */
593 outb (port
, com_fifo
, 0);
594 outb (port
, com_ier
, 0);
597 /* unhook handler, and disable interrupt gate */
598 dos_unhookirq (intrupt
);
599 outb (port
, com_mcr
, 0);
601 /* Check for overflow errors */
604 fprintf_unfiltered (gdb_stderr
,
605 "Serial input overruns occurred.\n");
606 fprintf_unfiltered (gdb_stderr
, "This system %s handle %d baud.\n",
607 port
->fifo
? "cannot" : "needs a 16550 to",
625 /* Always in raw mode */
629 dos_readchar (scb
, timeout
)
633 struct dos_ttystate
*port
= &ports
[scb
->fd
];
637 then
= rawclock () + (timeout
* RAWHZ
);
638 while ((c
= dos_getc (port
)) < 0)
640 if (timeout
>= 0 && (rawclock () - then
) >= 0)
641 return SERIAL_TIMEOUT
;
649 static serial_ttystate
650 dos_get_tty_state (scb
)
653 struct dos_ttystate
*port
= &ports
[scb
->fd
];
654 struct dos_ttystate
*state
;
656 state
= (struct dos_ttystate
*) xmalloc (sizeof *state
);
658 return (serial_ttystate
) state
;
662 dos_set_tty_state (scb
, ttystate
)
664 serial_ttystate ttystate
;
666 struct dos_ttystate
*state
;
668 state
= (struct dos_ttystate
*) ttystate
;
669 dos_setbaudrate (scb
, state
->baudrate
);
674 dos_noflush_set_tty_state (scb
, new_ttystate
, old_ttystate
)
676 serial_ttystate new_ttystate
;
677 serial_ttystate old_ttystate
;
679 struct dos_ttystate
*state
;
681 state
= (struct dos_ttystate
*) new_ttystate
;
682 dos_setbaudrate (scb
, state
->baudrate
);
687 dos_flush_input (scb
)
690 struct dos_ttystate
*port
= &ports
[scb
->fd
];
692 port
->first
= port
->count
= 0;
694 outb (port
, com_fifo
, FIFO_ENABLE
| FIFO_RCV_RST
| FIFO_TRIGGER
);
699 dos_print_tty_state (serial_t scb
,
700 serial_ttystate ttystate
,
701 struct gdb_file
*stream
)
703 /* Nothing to print */
716 #define divrnd(n, q) (((n) * 2 / (q) + 1) / 2) /* divide and round off */
717 x
= divrnd (COMTICK
, rate
);
721 err
= divrnd (1000 * COMTICK
, x
* rate
) - 1000;
724 if (err
> SPEED_TOLERANCE
)
732 dos_setbaudrate (scb
, rate
)
736 struct dos_ttystate
*port
= &ports
[scb
->fd
];
738 if (port
->baudrate
!= rate
)
743 x
= dos_baudconv (rate
);
746 fprintf_unfiltered (gdb_stderr
, "%d: impossible baudrate\n", rate
);
752 cfcr
= inb (port
, com_cfcr
);
754 outb (port
, com_cfcr
, CFCR_DLAB
);
755 outb (port
, com_dlbl
, x
& 0xff);
756 outb (port
, com_dlbh
, x
>> 8);
757 outb (port
, com_cfcr
, cfcr
);
758 port
->baudrate
= rate
;
766 dos_setstopbits (scb
, num
)
770 struct dos_ttystate
*port
= &ports
[scb
->fd
];
774 cfcr
= inb (port
, com_cfcr
);
778 case SERIAL_1_STOPBITS
:
779 outb (port
, com_cfcr
, cfcr
& ~CFCR_STOPB
);
781 case SERIAL_1_AND_A_HALF_STOPBITS
:
782 case SERIAL_2_STOPBITS
:
783 outb (port
, com_cfcr
, cfcr
| CFCR_STOPB
);
795 dos_write (scb
, str
, len
)
800 volatile struct dos_ttystate
*port
= &ports
[scb
->fd
];
801 int fifosize
= port
->fifo
? 16 : 1;
807 /* send the data, fifosize bytes at a time */
808 cnt
= fifosize
> len
? len
: fifosize
;
810 outportsb (port
->base
+ com_data
, str
, cnt
);
816 /* wait for transmission to complete (max 1 sec) */
817 then
= rawclock () + RAWHZ
;
820 if ((rawclock () - then
) >= 0)
835 volatile struct dos_ttystate
*port
= &ports
[scb
->fd
];
839 cfcr
= inb (port
, com_cfcr
);
840 outb (port
, com_cfcr
, cfcr
| CFCR_SBREAK
);
843 then
= rawclock () + RAWHZ
/ 4;
844 while ((rawclock () - then
) < 0)
847 outb (port
, com_cfcr
, cfcr
);
852 static struct serial_ops dos_ops
=
860 dos_noop
, /* flush output */
867 dos_noflush_set_tty_state
,
870 dos_noop
, /* wait for output to drain */
875 dos_info (arg
, from_tty
)
879 struct dos_ttystate
*port
;
882 for (port
= ports
; port
< &ports
[4]; port
++)
884 if (port
->baudrate
== 0)
886 printf_filtered ("Port:\tCOM%d (%sactive)\n", port
- ports
+ 1,
887 port
->intrupt
? "" : "not ");
888 printf_filtered ("Addr:\t0x%03x (irq %d)\n", port
->base
, port
->irq
);
889 printf_filtered ("16550:\t%s\n", port
->fifo
? "yes" : "no");
890 printf_filtered ("Speed:\t%d baud\n", port
->baudrate
);
891 printf_filtered ("Errs:\tframing %d parity %d overflow %d\n\n",
892 port
->ferr
, port
->perr
, port
->oflo
);
896 printf_filtered ("\nTotal interrupts: %d\n", intrcnt
);
897 for (i
= 0; i
< NCNT
; i
++)
899 printf_filtered ("%s:\t%d\n", cntnames
[i
], cnts
[i
]);
905 _initialize_ser_dos ()
907 struct cmd_list_element
*c
;
909 serial_add_interface (&dos_ops
);
911 /* Save original interrupt mask register. */
912 icu_oldmask
= inportb (ICU_MASK
);
914 /* Mark fixed motherboard irqs as inuse. */
915 intrupts
[0].inuse
= /* timer tick */
916 intrupts
[1].inuse
= /* keyboard */
917 intrupts
[2].inuse
= 1; /* slave icu */
920 add_set_cmd ("com1base", class_obscure
, var_zinteger
,
921 (char *) &ports
[0].base
,
922 "Set COM1 base i/o port address.",
927 add_set_cmd ("com1irq", class_obscure
, var_zinteger
,
928 (char *) &ports
[0].irq
,
929 "Set COM1 interrupt request.",
934 add_set_cmd ("com2base", class_obscure
, var_zinteger
,
935 (char *) &ports
[1].base
,
936 "Set COM2 base i/o port address.",
941 add_set_cmd ("com2irq", class_obscure
, var_zinteger
,
942 (char *) &ports
[1].irq
,
943 "Set COM2 interrupt request.",
948 add_set_cmd ("com3base", class_obscure
, var_zinteger
,
949 (char *) &ports
[2].base
,
950 "Set COM3 base i/o port address.",
955 add_set_cmd ("com3irq", class_obscure
, var_zinteger
,
956 (char *) &ports
[2].irq
,
957 "Set COM3 interrupt request.",
962 add_set_cmd ("com4base", class_obscure
, var_zinteger
,
963 (char *) &ports
[3].base
,
964 "Set COM4 base i/o port address.",
969 add_set_cmd ("com4irq", class_obscure
, var_zinteger
,
970 (char *) &ports
[3].irq
,
971 "Set COM4 interrupt request.",
975 add_info ("serial", dos_info
,
976 "Print DOS serial port status.");