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[MIPS] feature-removal-schedule.txt: Schedule au1x00_uart for removal.
[mirror_ubuntu-artful-kernel.git] / drivers / tc / zs.c
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1da177e4
LT		 1/*
2 * decserial.c: Serial port driver for IOASIC DECstations.
3 *
4 * Derived from drivers/sbus/char/sunserial.c by Paul Mackerras.
5 * Derived from drivers/macintosh/macserial.c by Harald Koerfgen.
6 *
7 * DECstation changes
8 * Copyright (C) 1998-2000 Harald Koerfgen
9 * Copyright (C) 2000, 2001, 2002, 2003, 2004 Maciej W. Rozycki
10 *
11 * For the rest of the code the original Copyright applies:
12 * Copyright (C) 1996 Paul Mackerras (Paul.Mackerras@cs.anu.edu.au)
13 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
14 *
15 *
16 * Note: for IOASIC systems the wiring is as follows:
17 *
18 * mouse/keyboard:
19 * DIN-7 MJ-4 signal SCC
20 * 2 1 TxD <- A.TxD
21 * 3 4 RxD -> A.RxD
22 *
23 * EIA-232/EIA-423:
24 * DB-25 MMJ-6 signal SCC
25 * 2 2 TxD <- B.TxD
26 * 3 5 RxD -> B.RxD
27 * 4 RTS <- ~A.RTS
28 * 5 CTS -> ~B.CTS
29 * 6 6 DSR -> ~A.SYNC
30 * 8 CD -> ~B.DCD
31 * 12 DSRS(DCE) -> ~A.CTS (*)
32 * 15 TxC -> B.TxC
33 * 17 RxC -> B.RxC
34 * 20 1 DTR <- ~A.DTR
35 * 22 RI -> ~A.DCD
36 * 23 DSRS(DTE) <- ~B.RTS
37 *
38 * (*) EIA-232 defines the signal at this pin to be SCD, while DSRS(DCE)
39 * is shared with DSRS(DTE) at pin 23.
40 */
41
42#include <linux/config.h>
43#include <linux/errno.h>
44#include <linux/signal.h>
45#include <linux/sched.h>
46#include <linux/timer.h>
47#include <linux/interrupt.h>
48#include <linux/tty.h>
49#include <linux/tty_flip.h>
50#include <linux/major.h>
51#include <linux/string.h>
52#include <linux/fcntl.h>
53#include <linux/mm.h>
54#include <linux/kernel.h>
55#include <linux/delay.h>
56#include <linux/init.h>
57#include <linux/ioport.h>
58#ifdef CONFIG_SERIAL_DEC_CONSOLE
59#include <linux/console.h>
60#endif
61
62#include <asm/io.h>
63#include <asm/pgtable.h>
64#include <asm/irq.h>
65#include <asm/system.h>
66#include <asm/uaccess.h>
67#include <asm/bootinfo.h>
1da177e4 68
1da177e4 69#include <asm/dec/interrupts.h>
a5fc9c0b 70#include <asm/dec/ioasic_addrs.h>
1da177e4 71#include <asm/dec/machtype.h>
a5fc9c0b
MR		 72#include <asm/dec/serial.h>
73#include <asm/dec/system.h>
1da177e4 74#include <asm/dec/tc.h>
a5fc9c0b 75
1da177e4
LT		 76#ifdef CONFIG_KGDB
77#include <asm/kgdb.h>
78#endif
79#ifdef CONFIG_MAGIC_SYSRQ
80#include <linux/sysrq.h>
81#endif
82
83#include "zs.h"
84
85/*
86 * It would be nice to dynamically allocate everything that
87 * depends on NUM_SERIAL, so we could support any number of
88 * Z8530s, but for now...
89 */
90#define NUM_SERIAL 2 /* Max number of ZS chips supported */
91#define NUM_CHANNELS (NUM_SERIAL * 2) /* 2 channels per chip */
92#define CHANNEL_A_NR (zs_parms->channel_a_offset > zs_parms->channel_b_offset)
93 /* Number of channel A in the chip */
94#define ZS_CHAN_IO_SIZE 8
95#define ZS_CLOCK 7372800 /* Z8530 RTxC input clock rate */
96
97#define RECOVERY_DELAY udelay(2)
98
99struct zs_parms {
100 unsigned long scc0;
101 unsigned long scc1;
102 int channel_a_offset;
103 int channel_b_offset;
104 int irq0;
105 int irq1;
106 int clock;
107};
108
109static struct zs_parms *zs_parms;
110
111#ifdef CONFIG_MACH_DECSTATION
112static struct zs_parms ds_parms = {
113 scc0 : IOASIC_SCC0,
114 scc1 : IOASIC_SCC1,
115 channel_a_offset : 1,
116 channel_b_offset : 9,
117 irq0 : -1,
118 irq1 : -1,
119 clock : ZS_CLOCK
120};
121#endif
122
123#ifdef CONFIG_MACH_DECSTATION
124#define DS_BUS_PRESENT (IOASIC)
125#else
126#define DS_BUS_PRESENT 0
127#endif
128
129#define BUS_PRESENT (DS_BUS_PRESENT)
130
131struct dec_zschannel zs_channels[NUM_CHANNELS];
132struct dec_serial zs_soft[NUM_CHANNELS];
133int zs_channels_found;
134struct dec_serial *zs_chain; /* list of all channels */
135
136struct tty_struct zs_ttys[NUM_CHANNELS];
137
138#ifdef CONFIG_SERIAL_DEC_CONSOLE
139static struct console sercons;
140#endif
141#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
142 !defined(MODULE)
143static unsigned long break_pressed; /* break, really ... */
144#endif
145
146static unsigned char zs_init_regs[16] __initdata = {
147 0, /* write 0 */
148 0, /* write 1 */
149 0, /* write 2 */
150 0, /* write 3 */
151 (X16CLK), /* write 4 */
152 0, /* write 5 */
153 0, 0, 0, /* write 6, 7, 8 */
154 (MIE | DLC | NV), /* write 9 */
155 (NRZ), /* write 10 */
156 (TCBR | RCBR), /* write 11 */
157 0, 0, /* BRG time constant, write 12 + 13 */
158 (BRSRC | BRENABL), /* write 14 */
159 0 /* write 15 */
160};
161
162DECLARE_TASK_QUEUE(tq_zs_serial);
163
164static struct tty_driver *serial_driver;
165
166/* serial subtype definitions */
167#define SERIAL_TYPE_NORMAL 1
168
169/* number of characters left in xmit buffer before we ask for more */
170#define WAKEUP_CHARS 256
171
172/*
173 * Debugging.
174 */
175#undef SERIAL_DEBUG_OPEN
176#undef SERIAL_DEBUG_FLOW
177#undef SERIAL_DEBUG_THROTTLE
178#undef SERIAL_PARANOIA_CHECK
179
180#undef ZS_DEBUG_REGS
181
182#ifdef SERIAL_DEBUG_THROTTLE
183#define _tty_name(tty,buf) tty_name(tty,buf)
184#endif
185
186#define RS_STROBE_TIME 10
187#define RS_ISR_PASS_LIMIT 256
188
189#define _INLINE_ inline
190
191static void probe_sccs(void);
192static void change_speed(struct dec_serial *info);
193static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
194
1da177e4
LT		 195static inline int serial_paranoia_check(struct dec_serial *info,
196 char *name, const char *routine)
197{
198#ifdef SERIAL_PARANOIA_CHECK
199 static const char *badmagic =
200 "Warning: bad magic number for serial struct %s in %s\n";
201 static const char *badinfo =
202 "Warning: null mac_serial for %s in %s\n";
203
204 if (!info) {
205 printk(badinfo, name, routine);
206 return 1;
207 }
208 if (info->magic != SERIAL_MAGIC) {
209 printk(badmagic, name, routine);
210 return 1;
211 }
212#endif
213 return 0;
214}
215
216/*
217 * This is used to figure out the divisor speeds and the timeouts
218 */
219static int baud_table[] = {
220 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
221 9600, 19200, 38400, 57600, 115200, 0 };
222
223/*
224 * Reading and writing Z8530 registers.
225 */
226static inline unsigned char read_zsreg(struct dec_zschannel *channel,
227 unsigned char reg)
228{
229 unsigned char retval;
230
231 if (reg != 0) {
232 *channel->control = reg & 0xf;
233 fast_iob(); RECOVERY_DELAY;
234 }
235 retval = *channel->control;
236 RECOVERY_DELAY;
237 return retval;
238}
239
240static inline void write_zsreg(struct dec_zschannel *channel,
241 unsigned char reg, unsigned char value)
242{
243 if (reg != 0) {
244 *channel->control = reg & 0xf;
245 fast_iob(); RECOVERY_DELAY;
246 }
247 *channel->control = value;
248 fast_iob(); RECOVERY_DELAY;
249 return;
250}
251
252static inline unsigned char read_zsdata(struct dec_zschannel *channel)
253{
254 unsigned char retval;
255
256 retval = *channel->data;
257 RECOVERY_DELAY;
258 return retval;
259}
260
261static inline void write_zsdata(struct dec_zschannel *channel,
262 unsigned char value)
263{
264 *channel->data = value;
265 fast_iob(); RECOVERY_DELAY;
266 return;
267}
268
269static inline void load_zsregs(struct dec_zschannel *channel,
270 unsigned char *regs)
271{
272/* ZS_CLEARERR(channel);
273 ZS_CLEARFIFO(channel); */
274 /* Load 'em up */
275 write_zsreg(channel, R3, regs[R3] & ~RxENABLE);
276 write_zsreg(channel, R5, regs[R5] & ~TxENAB);
277 write_zsreg(channel, R4, regs[R4]);
278 write_zsreg(channel, R9, regs[R9]);
279 write_zsreg(channel, R1, regs[R1]);
280 write_zsreg(channel, R2, regs[R2]);
281 write_zsreg(channel, R10, regs[R10]);
282 write_zsreg(channel, R11, regs[R11]);
283 write_zsreg(channel, R12, regs[R12]);
284 write_zsreg(channel, R13, regs[R13]);
285 write_zsreg(channel, R14, regs[R14]);
286 write_zsreg(channel, R15, regs[R15]);
287 write_zsreg(channel, R3, regs[R3]);
288 write_zsreg(channel, R5, regs[R5]);
289 return;
290}
291
292/* Sets or clears DTR/RTS on the requested line */
293static inline void zs_rtsdtr(struct dec_serial *info, int which, int set)
294{
295 unsigned long flags;
296
297
298 save_flags(flags); cli();
299 if (info->zs_channel != info->zs_chan_a) {
300 if (set) {
301 info->zs_chan_a->curregs[5] |= (which & (RTS | DTR));
302 } else {
303 info->zs_chan_a->curregs[5] &= ~(which & (RTS | DTR));
304 }
305 write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
306 }
307 restore_flags(flags);
308}
309
310/* Utility routines for the Zilog */
311static inline int get_zsbaud(struct dec_serial *ss)
312{
313 struct dec_zschannel *channel = ss->zs_channel;
314 int brg;
315
316 /* The baud rate is split up between two 8-bit registers in
317 * what is termed 'BRG time constant' format in my docs for
318 * the chip, it is a function of the clk rate the chip is
319 * receiving which happens to be constant.
320 */
321 brg = (read_zsreg(channel, 13) << 8);
322 brg |= read_zsreg(channel, 12);
323 return BRG_TO_BPS(brg, (zs_parms->clock/(ss->clk_divisor)));
324}
325
326/* On receive, this clears errors and the receiver interrupts */
327static inline void rs_recv_clear(struct dec_zschannel *zsc)
328{
329 write_zsreg(zsc, 0, ERR_RES);
330 write_zsreg(zsc, 0, RES_H_IUS); /* XXX this is unnecessary */
331}
332
333/*
334 * ----------------------------------------------------------------------
335 *
336 * Here starts the interrupt handling routines. All of the following
337 * subroutines are declared as inline and are folded into
338 * rs_interrupt(). They were separated out for readability's sake.
339 *
340 * - Ted Ts'o (tytso@mit.edu), 7-Mar-93
341 * -----------------------------------------------------------------------
342 */
343
344/*
345 * This routine is used by the interrupt handler to schedule
346 * processing in the software interrupt portion of the driver.
347 */
348static _INLINE_ void rs_sched_event(struct dec_serial *info,
349 int event)
350{
351 info->event |= 1 << event;
352 queue_task(&info->tqueue, &tq_zs_serial);
353 mark_bh(SERIAL_BH);
354}
355
356static _INLINE_ void receive_chars(struct dec_serial *info,
357 struct pt_regs *regs)
358{
359 struct tty_struct *tty = info->tty;
360 unsigned char ch, stat, flag;
361
362 while ((read_zsreg(info->zs_channel, R0) & Rx_CH_AV) != 0) {
363
364 stat = read_zsreg(info->zs_channel, R1);
365 ch = read_zsdata(info->zs_channel);
366
367 if (!tty && (!info->hook || !info->hook->rx_char))
368 continue;
369
370 flag = TTY_NORMAL;
371 if (info->tty_break) {
372 info->tty_break = 0;
373 flag = TTY_BREAK;
374 if (info->flags & ZILOG_SAK)
375 do_SAK(tty);
376 /* Ignore the null char got when BREAK is removed. */
377 if (ch == 0)
378 continue;
379 } else {
380 if (stat & Rx_OVR) {
381 flag = TTY_OVERRUN;
382 } else if (stat & FRM_ERR) {
383 flag = TTY_FRAME;
384 } else if (stat & PAR_ERR) {
385 flag = TTY_PARITY;
386 }
387 if (flag != TTY_NORMAL)
388 /* reset the error indication */
389 write_zsreg(info->zs_channel, R0, ERR_RES);
390 }
391
392#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
393 !defined(MODULE)
394 if (break_pressed && info->line == sercons.index) {
395 /* Ignore the null char got when BREAK is removed. */
396 if (ch == 0)
397 continue;
398 if (time_before(jiffies, break_pressed + HZ * 5)) {
399 handle_sysrq(ch, regs, NULL);
400 break_pressed = 0;
401 continue;
402 }
403 break_pressed = 0;
404 }
405#endif
406
407 if (info->hook && info->hook->rx_char) {
408 (*info->hook->rx_char)(ch, flag);
409 return;
410 }
411
412 tty_insert_flip_char(tty, ch, flag);
413 }
414 if (tty)
415 tty_flip_buffer_push(tty);
416}
417
418static void transmit_chars(struct dec_serial *info)
419{
420 if ((read_zsreg(info->zs_channel, R0) & Tx_BUF_EMP) == 0)
421 return;
422 info->tx_active = 0;
423
424 if (info->x_char) {
425 /* Send next char */
426 write_zsdata(info->zs_channel, info->x_char);
427 info->x_char = 0;
428 info->tx_active = 1;
429 return;
430 }
431
432 if ((info->xmit_cnt <= 0) || (info->tty && info->tty->stopped)
433 || info->tx_stopped) {
434 write_zsreg(info->zs_channel, R0, RES_Tx_P);
435 return;
436 }
437 /* Send char */
438 write_zsdata(info->zs_channel, info->xmit_buf[info->xmit_tail++]);
439 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
440 info->xmit_cnt--;
441 info->tx_active = 1;
442
443 if (info->xmit_cnt < WAKEUP_CHARS)
444 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
445}
446
447static _INLINE_ void status_handle(struct dec_serial *info)
448{
449 unsigned char stat;
450
451 /* Get status from Read Register 0 */
452 stat = read_zsreg(info->zs_channel, R0);
453
454 if ((stat & BRK_ABRT) && !(info->read_reg_zero & BRK_ABRT)) {
455#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
456 !defined(MODULE)
457 if (info->line == sercons.index) {
458 if (!break_pressed)
459 break_pressed = jiffies;
460 } else
461#endif
462 info->tty_break = 1;
463 }
464
465 if (info->zs_channel != info->zs_chan_a) {
466
467 /* Check for DCD transitions */
468 if (info->tty && !C_CLOCAL(info->tty) &&
469 ((stat ^ info->read_reg_zero) & DCD) != 0 ) {
470 if (stat & DCD) {
471 wake_up_interruptible(&info->open_wait);
472 } else {
473 tty_hangup(info->tty);
474 }
475 }
476
477 /* Check for CTS transitions */
478 if (info->tty && C_CRTSCTS(info->tty)) {
479 if ((stat & CTS) != 0) {
480 if (info->tx_stopped) {
481 info->tx_stopped = 0;
482 if (!info->tx_active)
483 transmit_chars(info);
484 }
485 } else {
486 info->tx_stopped = 1;
487 }
488 }
489
490 }
491
492 /* Clear status condition... */
493 write_zsreg(info->zs_channel, R0, RES_EXT_INT);
494 info->read_reg_zero = stat;
495}
496
497/*
498 * This is the serial driver's generic interrupt routine
499 */
500void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
501{
502 struct dec_serial *info = (struct dec_serial *) dev_id;
503 unsigned char zs_intreg;
504 int shift;
505
506 /* NOTE: The read register 3, which holds the irq status,
507 * does so for both channels on each chip. Although
508 * the status value itself must be read from the A
509 * channel and is only valid when read from channel A.
510 * Yes... broken hardware...
511 */
512#define CHAN_IRQMASK (CHBRxIP | CHBTxIP | CHBEXT)
513
514 if (info->zs_chan_a == info->zs_channel)
515 shift = 3; /* Channel A */
516 else
517 shift = 0; /* Channel B */
518
519 for (;;) {
520 zs_intreg = read_zsreg(info->zs_chan_a, R3) >> shift;
521 if ((zs_intreg & CHAN_IRQMASK) == 0)
522 break;
523
524 if (zs_intreg & CHBRxIP) {
525 receive_chars(info, regs);
526 }
527 if (zs_intreg & CHBTxIP) {
528 transmit_chars(info);
529 }
530 if (zs_intreg & CHBEXT) {
531 status_handle(info);
532 }
533 }
534
535 /* Why do we need this ? */
536 write_zsreg(info->zs_channel, 0, RES_H_IUS);
537}
538
539#ifdef ZS_DEBUG_REGS
540void zs_dump (void) {
541 int i, j;
542 for (i = 0; i < zs_channels_found; i++) {
543 struct dec_zschannel *ch = &zs_channels[i];
544 if ((long)ch->control == UNI_IO_BASE+UNI_SCC1A_CTRL) {
545 for (j = 0; j < 15; j++) {
546 printk("W%d = 0x%x\t",
547 j, (int)ch->curregs[j]);
548 }
549 for (j = 0; j < 15; j++) {
550 printk("R%d = 0x%x\t",
551 j, (int)read_zsreg(ch,j));
552 }
553 printk("\n\n");
554 }
555 }
556}
557#endif
558
559/*
560 * -------------------------------------------------------------------
561 * Here ends the serial interrupt routines.
562 * -------------------------------------------------------------------
563 */
564
565/*
566 * ------------------------------------------------------------
567 * rs_stop() and rs_start()
568 *
569 * This routines are called before setting or resetting tty->stopped.
570 * ------------------------------------------------------------
571 */
572static void rs_stop(struct tty_struct *tty)
573{
574 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
575 unsigned long flags;
576
577 if (serial_paranoia_check(info, tty->name, "rs_stop"))
578 return;
579
580#if 1
581 save_flags(flags); cli();
582 if (info->zs_channel->curregs[5] & TxENAB) {
583 info->zs_channel->curregs[5] &= ~TxENAB;
584 write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
585 }
586 restore_flags(flags);
587#endif
588}
589
590static void rs_start(struct tty_struct *tty)
591{
592 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
593 unsigned long flags;
594
595 if (serial_paranoia_check(info, tty->name, "rs_start"))
596 return;
597
598 save_flags(flags); cli();
599#if 1
600 if (info->xmit_cnt && info->xmit_buf && !(info->zs_channel->curregs[5] & TxENAB)) {
601 info->zs_channel->curregs[5] |= TxENAB;
602 write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
603 }
604#else
605 if (info->xmit_cnt && info->xmit_buf && !info->tx_active) {
606 transmit_chars(info);
607 }
608#endif
609 restore_flags(flags);
610}
611
612/*
613 * This routine is used to handle the "bottom half" processing for the
614 * serial driver, known also the "software interrupt" processing.
615 * This processing is done at the kernel interrupt level, after the
616 * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON. This
617 * is where time-consuming activities which can not be done in the
618 * interrupt driver proper are done; the interrupt driver schedules
619 * them using rs_sched_event(), and they get done here.
620 */
621static void do_serial_bh(void)
622{
623 run_task_queue(&tq_zs_serial);
624}
625
626static void do_softint(void *private_)
627{
628 struct dec_serial *info = (struct dec_serial *) private_;
629 struct tty_struct *tty;
630
631 tty = info->tty;
632 if (!tty)
633 return;
634
635 if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
636 tty_wakeup(tty);
637 }
638}
639
640int zs_startup(struct dec_serial * info)
641{
642 unsigned long flags;
643
644 if (info->flags & ZILOG_INITIALIZED)
645 return 0;
646
647 if (!info->xmit_buf) {
648 info->xmit_buf = (unsigned char *) get_zeroed_page(GFP_KERNEL);
649 if (!info->xmit_buf)
650 return -ENOMEM;
651 }
652
653 save_flags(flags); cli();
654
655#ifdef SERIAL_DEBUG_OPEN
656 printk("starting up ttyS%d (irq %d)...", info->line, info->irq);
657#endif
658
659 /*
660 * Clear the receive FIFO.
661 */
662 ZS_CLEARFIFO(info->zs_channel);
663 info->xmit_fifo_size = 1;
664
665 /*
666 * Clear the interrupt registers.
667 */
668 write_zsreg(info->zs_channel, R0, ERR_RES);
669 write_zsreg(info->zs_channel, R0, RES_H_IUS);
670
671 /*
672 * Set the speed of the serial port
673 */
674 change_speed(info);
675
676 /*
677 * Turn on RTS and DTR.
678 */
679 zs_rtsdtr(info, RTS | DTR, 1);
680
681 /*
682 * Finally, enable sequencing and interrupts
683 */
684 info->zs_channel->curregs[R1] &= ~RxINT_MASK;
685 info->zs_channel->curregs[R1] |= (RxINT_ALL | TxINT_ENAB |
686 EXT_INT_ENAB);
687 info->zs_channel->curregs[R3] |= RxENABLE;
688 info->zs_channel->curregs[R5] |= TxENAB;
689 info->zs_channel->curregs[R15] |= (DCDIE | CTSIE | TxUIE | BRKIE);
690 write_zsreg(info->zs_channel, R1, info->zs_channel->curregs[R1]);
691 write_zsreg(info->zs_channel, R3, info->zs_channel->curregs[R3]);
692 write_zsreg(info->zs_channel, R5, info->zs_channel->curregs[R5]);
693 write_zsreg(info->zs_channel, R15, info->zs_channel->curregs[R15]);
694
695 /*
696 * And clear the interrupt registers again for luck.
697 */
698 write_zsreg(info->zs_channel, R0, ERR_RES);
699 write_zsreg(info->zs_channel, R0, RES_H_IUS);
700
701 /* Save the current value of RR0 */
702 info->read_reg_zero = read_zsreg(info->zs_channel, R0);
703
704 if (info->tty)
705 clear_bit(TTY_IO_ERROR, &info->tty->flags);
706 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
707
708 info->flags |= ZILOG_INITIALIZED;
709 restore_flags(flags);
710 return 0;
711}
712
713/*
714 * This routine will shutdown a serial port; interrupts are disabled, and
715 * DTR is dropped if the hangup on close termio flag is on.
716 */
717static void shutdown(struct dec_serial * info)
718{
719 unsigned long flags;
720
721 if (!(info->flags & ZILOG_INITIALIZED))
722 return;
723
724#ifdef SERIAL_DEBUG_OPEN
725 printk("Shutting down serial port %d (irq %d)....", info->line,
726 info->irq);
727#endif
728
729 save_flags(flags); cli(); /* Disable interrupts */
730
731 if (info->xmit_buf) {
732 free_page((unsigned long) info->xmit_buf);
733 info->xmit_buf = 0;
734 }
735
736 info->zs_channel->curregs[1] = 0;
737 write_zsreg(info->zs_channel, 1, info->zs_channel->curregs[1]); /* no interrupts */
738
739 info->zs_channel->curregs[3] &= ~RxENABLE;
740 write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
741
742 info->zs_channel->curregs[5] &= ~TxENAB;
743 write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
744 if (!info->tty || C_HUPCL(info->tty)) {
745 zs_rtsdtr(info, RTS | DTR, 0);
746 }
747
748 if (info->tty)
749 set_bit(TTY_IO_ERROR, &info->tty->flags);
750
751 info->flags &= ~ZILOG_INITIALIZED;
752 restore_flags(flags);
753}
754
755/*
756 * This routine is called to set the UART divisor registers to match
757 * the specified baud rate for a serial port.
758 */
759static void change_speed(struct dec_serial *info)
760{
761 unsigned cflag;
762 int i;
763 int brg, bits;
764 unsigned long flags;
765
766 if (!info->hook) {
767 if (!info->tty || !info->tty->termios)
768 return;
769 cflag = info->tty->termios->c_cflag;
770 if (!info->port)
771 return;
772 } else {
773 cflag = info->hook->cflags;
774 }
775
776 i = cflag & CBAUD;
777 if (i & CBAUDEX) {
778 i &= ~CBAUDEX;
779 if (i < 1 || i > 2) {
780 if (!info->hook)
781 info->tty->termios->c_cflag &= ~CBAUDEX;
782 else
783 info->hook->cflags &= ~CBAUDEX;
784 } else
785 i += 15;
786 }
787
788 save_flags(flags); cli();
789 info->zs_baud = baud_table[i];
790 if (info->zs_baud) {
791 brg = BPS_TO_BRG(info->zs_baud, zs_parms->clock/info->clk_divisor);
792 info->zs_channel->curregs[12] = (brg & 255);
793 info->zs_channel->curregs[13] = ((brg >> 8) & 255);
794 zs_rtsdtr(info, DTR, 1);
795 } else {
796 zs_rtsdtr(info, RTS | DTR, 0);
797 return;
798 }
799
800 /* byte size and parity */
801 info->zs_channel->curregs[3] &= ~RxNBITS_MASK;
802 info->zs_channel->curregs[5] &= ~TxNBITS_MASK;
803 switch (cflag & CSIZE) {
804 case CS5:
805 bits = 7;
806 info->zs_channel->curregs[3] |= Rx5;
807 info->zs_channel->curregs[5] |= Tx5;
808 break;
809 case CS6:
810 bits = 8;
811 info->zs_channel->curregs[3] |= Rx6;
812 info->zs_channel->curregs[5] |= Tx6;
813 break;
814 case CS7:
815 bits = 9;
816 info->zs_channel->curregs[3] |= Rx7;
817 info->zs_channel->curregs[5] |= Tx7;
818 break;
819 case CS8:
820 default: /* defaults to 8 bits */
821 bits = 10;
822 info->zs_channel->curregs[3] |= Rx8;
823 info->zs_channel->curregs[5] |= Tx8;
824 break;
825 }
826
827 info->timeout = ((info->xmit_fifo_size*HZ*bits) / info->zs_baud);
828 info->timeout += HZ/50; /* Add .02 seconds of slop */
829
830 info->zs_channel->curregs[4] &= ~(SB_MASK | PAR_ENA | PAR_EVEN);
831 if (cflag & CSTOPB) {
832 info->zs_channel->curregs[4] |= SB2;
833 } else {
834 info->zs_channel->curregs[4] |= SB1;
835 }
836 if (cflag & PARENB) {
837 info->zs_channel->curregs[4] |= PAR_ENA;
838 }
839 if (!(cflag & PARODD)) {
840 info->zs_channel->curregs[4] |= PAR_EVEN;
841 }
842
843 if (!(cflag & CLOCAL)) {
844 if (!(info->zs_channel->curregs[15] & DCDIE))
845 info->read_reg_zero = read_zsreg(info->zs_channel, 0);
846 info->zs_channel->curregs[15] |= DCDIE;
847 } else
848 info->zs_channel->curregs[15] &= ~DCDIE;
849 if (cflag & CRTSCTS) {
850 info->zs_channel->curregs[15] |= CTSIE;
851 if ((read_zsreg(info->zs_channel, 0) & CTS) == 0)
852 info->tx_stopped = 1;
853 } else {
854 info->zs_channel->curregs[15] &= ~CTSIE;
855 info->tx_stopped = 0;
856 }
857
858 /* Load up the new values */
859 load_zsregs(info->zs_channel, info->zs_channel->curregs);
860
861 restore_flags(flags);
862}
863
864static void rs_flush_chars(struct tty_struct *tty)
865{
866 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
867 unsigned long flags;
868
869 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
870 return;
871
872 if (info->xmit_cnt <= 0 || tty->stopped || info->tx_stopped ||
873 !info->xmit_buf)
874 return;
875
876 /* Enable transmitter */
877 save_flags(flags); cli();
878 transmit_chars(info);
879 restore_flags(flags);
880}
881
882static int rs_write(struct tty_struct * tty,
883 const unsigned char *buf, int count)
884{
885 int c, total = 0;
886 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
887 unsigned long flags;
888
889 if (serial_paranoia_check(info, tty->name, "rs_write"))
890 return 0;
891
892 if (!tty || !info->xmit_buf)
893 return 0;
894
895 save_flags(flags);
896 while (1) {
897 cli();
898 c = min(count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
899 SERIAL_XMIT_SIZE - info->xmit_head));
900 if (c <= 0)
901 break;
902
903 if (from_user) {
904 down(&tmp_buf_sem);
905 copy_from_user(tmp_buf, buf, c);
906 c = min(c, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
907 SERIAL_XMIT_SIZE - info->xmit_head));
908 memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
909 up(&tmp_buf_sem);
910 } else
911 memcpy(info->xmit_buf + info->xmit_head, buf, c);
912 info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
913 info->xmit_cnt += c;
914 restore_flags(flags);
915 buf += c;
916 count -= c;
917 total += c;
918 }
919
920 if (info->xmit_cnt && !tty->stopped && !info->tx_stopped
921 && !info->tx_active)
922 transmit_chars(info);
923 restore_flags(flags);
924 return total;
925}
926
927static int rs_write_room(struct tty_struct *tty)
928{
929 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
930 int ret;
931
932 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
933 return 0;
934 ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
935 if (ret < 0)
936 ret = 0;
937 return ret;
938}
939
940static int rs_chars_in_buffer(struct tty_struct *tty)
941{
942 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
943
944 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
945 return 0;
946 return info->xmit_cnt;
947}
948
949static void rs_flush_buffer(struct tty_struct *tty)
950{
951 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
952
953 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
954 return;
955 cli();
956 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
957 sti();
958 tty_wakeup(tty);
959}
960
961/*
962 * ------------------------------------------------------------
963 * rs_throttle()
964 *
965 * This routine is called by the upper-layer tty layer to signal that
966 * incoming characters should be throttled.
967 * ------------------------------------------------------------
968 */
969static void rs_throttle(struct tty_struct * tty)
970{
971 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
972 unsigned long flags;
973
974#ifdef SERIAL_DEBUG_THROTTLE
975 char buf[64];
976
977 printk("throttle %s: %d....\n", _tty_name(tty, buf),
978 tty->ldisc.chars_in_buffer(tty));
979#endif
980
981 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
982 return;
983
984 if (I_IXOFF(tty)) {
985 save_flags(flags); cli();
986 info->x_char = STOP_CHAR(tty);
987 if (!info->tx_active)
988 transmit_chars(info);
989 restore_flags(flags);
990 }
991
992 if (C_CRTSCTS(tty)) {
993 zs_rtsdtr(info, RTS, 0);
994 }
995}
996
997static void rs_unthrottle(struct tty_struct * tty)
998{
999 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
1000 unsigned long flags;
1001
1002#ifdef SERIAL_DEBUG_THROTTLE
1003 char buf[64];
1004
1005 printk("unthrottle %s: %d....\n", _tty_name(tty, buf),
1006 tty->ldisc.chars_in_buffer(tty));
1007#endif
1008
1009 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1010 return;
1011
1012 if (I_IXOFF(tty)) {
1013 save_flags(flags); cli();
1014 if (info->x_char)
1015 info->x_char = 0;
1016 else {
1017 info->x_char = START_CHAR(tty);
1018 if (!info->tx_active)
1019 transmit_chars(info);
1020 }
1021 restore_flags(flags);
1022 }
1023
1024 if (C_CRTSCTS(tty)) {
1025 zs_rtsdtr(info, RTS, 1);
1026 }
1027}
1028
1029/*
1030 * ------------------------------------------------------------
1031 * rs_ioctl() and friends
1032 * ------------------------------------------------------------
1033 */
1034
1035static int get_serial_info(struct dec_serial * info,
1036 struct serial_struct * retinfo)
1037{
1038 struct serial_struct tmp;
1039
1040 if (!retinfo)
1041 return -EFAULT;
1042 memset(&tmp, 0, sizeof(tmp));
1043 tmp.type = info->type;
1044 tmp.line = info->line;
1045 tmp.port = info->port;
1046 tmp.irq = info->irq;
1047 tmp.flags = info->flags;
1048 tmp.baud_base = info->baud_base;
1049 tmp.close_delay = info->close_delay;
1050 tmp.closing_wait = info->closing_wait;
1051 tmp.custom_divisor = info->custom_divisor;
1052 return copy_to_user(retinfo,&tmp,sizeof(*retinfo)) ? -EFAULT : 0;
1053}
1054
1055static int set_serial_info(struct dec_serial * info,
1056 struct serial_struct * new_info)
1057{
1058 struct serial_struct new_serial;
1059 struct dec_serial old_info;
1060 int retval = 0;
1061
1062 if (!new_info)
1063 return -EFAULT;
1064 copy_from_user(&new_serial,new_info,sizeof(new_serial));
1065 old_info = *info;
1066
1067 if (!capable(CAP_SYS_ADMIN)) {
1068 if ((new_serial.baud_base != info->baud_base) ||
1069 (new_serial.type != info->type) ||
1070 (new_serial.close_delay != info->close_delay) ||
1071 ((new_serial.flags & ~ZILOG_USR_MASK) !=
1072 (info->flags & ~ZILOG_USR_MASK)))
1073 return -EPERM;
1074 info->flags = ((info->flags & ~ZILOG_USR_MASK) |
1075 (new_serial.flags & ZILOG_USR_MASK));
1076 info->custom_divisor = new_serial.custom_divisor;
1077 goto check_and_exit;
1078 }
1079
1080 if (info->count > 1)
1081 return -EBUSY;
1082
1083 /*
1084 * OK, past this point, all the error checking has been done.
1085 * At this point, we start making changes.....
1086 */
1087
1088 info->baud_base = new_serial.baud_base;
1089 info->flags = ((info->flags & ~ZILOG_FLAGS) |
1090 (new_serial.flags & ZILOG_FLAGS));
1091 info->type = new_serial.type;
1092 info->close_delay = new_serial.close_delay;
1093 info->closing_wait = new_serial.closing_wait;
1094
1095check_and_exit:
1096 retval = zs_startup(info);
1097 return retval;
1098}
1099
1100/*
1101 * get_lsr_info - get line status register info
1102 *
1103 * Purpose: Let user call ioctl() to get info when the UART physically
1104 * is emptied. On bus types like RS485, the transmitter must
1105 * release the bus after transmitting. This must be done when
1106 * the transmit shift register is empty, not be done when the
1107 * transmit holding register is empty. This functionality
1108 * allows an RS485 driver to be written in user space.
1109 */
1110static int get_lsr_info(struct dec_serial * info, unsigned int *value)
1111{
1112 unsigned char status;
1113
1114 cli();
1115 status = read_zsreg(info->zs_channel, 0);
1116 sti();
1117 put_user(status,value);
1118 return 0;
1119}
1120
1121static int rs_tiocmget(struct tty_struct *tty, struct file *file)
1122{
1123 struct dec_serial * info = (struct dec_serial *)tty->driver_data;
1124 unsigned char control, status_a, status_b;
1125 unsigned int result;
1126
1127 if (info->hook)
1128 return -ENODEV;
1129
1130 if (serial_paranoia_check(info, tty->name, __FUNCTION__))
1131 return -ENODEV;
1132
1133 if (tty->flags & (1 << TTY_IO_ERROR))
1134 return -EIO;
1135
1136 if (info->zs_channel == info->zs_chan_a)
1137 result = 0;
1138 else {
1139 cli();
1140 control = info->zs_chan_a->curregs[5];
1141 status_a = read_zsreg(info->zs_chan_a, 0);
1142 status_b = read_zsreg(info->zs_channel, 0);
1143 sti();
1144 result = ((control & RTS) ? TIOCM_RTS: 0)
1145 | ((control & DTR) ? TIOCM_DTR: 0)
1146 | ((status_b & DCD) ? TIOCM_CAR: 0)
1147 | ((status_a & DCD) ? TIOCM_RNG: 0)
1148 | ((status_a & SYNC_HUNT) ? TIOCM_DSR: 0)
1149 | ((status_b & CTS) ? TIOCM_CTS: 0);
1150 }
1151 return result;
1152}
1153
1154static int rs_tiocmset(struct tty_struct *tty, struct file *file,
1155 unsigned int set, unsigned int clear)
1156{
1157 struct dec_serial * info = (struct dec_serial *)tty->driver_data;
1158 int error;
1159 unsigned int arg, bits;
1160
1161 if (info->hook)
1162 return -ENODEV;
1163
1164 if (serial_paranoia_check(info, tty->name, __FUNCTION__))
1165 return -ENODEV;
1166
1167 if (tty->flags & (1 << TTY_IO_ERROR))
1168 return -EIO;
1169
1170 if (info->zs_channel == info->zs_chan_a)
1171 return 0;
1172
1173 get_user(arg, value);
1174 cli();
1175 if (set & TIOCM_RTS)
1176 info->zs_chan_a->curregs[5] |= RTS;
1177 if (set & TIOCM_DTR)
1178 info->zs_chan_a->curregs[5] |= DTR;
1179 if (clear & TIOCM_RTS)
1180 info->zs_chan_a->curregs[5] &= ~RTS;
1181 if (clear & TIOCM_DTR)
1182 info->zs_chan_a->curregs[5] &= ~DTR;
1183 write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
1184 sti();
1185 return 0;
1186}
1187
1188/*
1189 * rs_break - turn transmit break condition on/off
1190 */
1191static void rs_break(struct tty_struct *tty, int break_state)
1192{
1193 struct dec_serial *info = (struct dec_serial *) tty->driver_data;
1194 unsigned long flags;
1195
1196 if (serial_paranoia_check(info, tty->name, "rs_break"))
1197 return;
1198 if (!info->port)
1199 return;
1200
1201 save_flags(flags); cli();
1202 if (break_state == -1)
1203 info->zs_channel->curregs[5] |= SND_BRK;
1204 else
1205 info->zs_channel->curregs[5] &= ~SND_BRK;
1206 write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
1207 restore_flags(flags);
1208}
1209
1210static int rs_ioctl(struct tty_struct *tty, struct file * file,
1211 unsigned int cmd, unsigned long arg)
1212{
1213 int error;
1214 struct dec_serial * info = (struct dec_serial *)tty->driver_data;
1215
1216 if (info->hook)
1217 return -ENODEV;
1218
1219 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1220 return -ENODEV;
1221
1222 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1223 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
1224 (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
1225 if (tty->flags & (1 << TTY_IO_ERROR))
1226 return -EIO;
1227 }
1228
1229 switch (cmd) {
1230 case TIOCGSERIAL:
1231 if (!access_ok(VERIFY_WRITE, (void *)arg,
1232 sizeof(struct serial_struct)))
1233 return -EFAULT;
1234 return get_serial_info(info, (struct serial_struct *)arg);
1235
1236 case TIOCSSERIAL:
1237 return set_serial_info(info, (struct serial_struct *)arg);
1238
1239 case TIOCSERGETLSR: /* Get line status register */
1240 if (!access_ok(VERIFY_WRITE, (void *)arg,
1241 sizeof(unsigned int)))
1242 return -EFAULT;
1243 return get_lsr_info(info, (unsigned int *)arg);
1244
1245 case TIOCSERGSTRUCT:
1246 if (!access_ok(VERIFY_WRITE, (void *)arg,
1247 sizeof(struct dec_serial)))
1248 return -EFAULT;
1249 copy_from_user((struct dec_serial *)arg, info,
1250 sizeof(struct dec_serial));
1251 return 0;
1252
1253 default:
1254 return -ENOIOCTLCMD;
1255 }
1256 return 0;
1257}
1258
1259static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
1260{
1261 struct dec_serial *info = (struct dec_serial *)tty->driver_data;
1262 int was_stopped;
1263
1264 if (tty->termios->c_cflag == old_termios->c_cflag)
1265 return;
1266 was_stopped = info->tx_stopped;
1267
1268 change_speed(info);
1269
1270 if (was_stopped && !info->tx_stopped)
1271 rs_start(tty);
1272}
1273
1274/*
1275 * ------------------------------------------------------------
1276 * rs_close()
1277 *
1278 * This routine is called when the serial port gets closed.
1279 * Wait for the last remaining data to be sent.
1280 * ------------------------------------------------------------
1281 */
1282static void rs_close(struct tty_struct *tty, struct file * filp)
1283{
1284 struct dec_serial * info = (struct dec_serial *)tty->driver_data;
1285 unsigned long flags;
1286
1287 if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1288 return;
1289
1290 save_flags(flags); cli();
1291
1292 if (tty_hung_up_p(filp)) {
1293 restore_flags(flags);
1294 return;
1295 }
1296
1297#ifdef SERIAL_DEBUG_OPEN
1298 printk("rs_close ttyS%d, count = %d\n", info->line, info->count);
1299#endif
1300 if ((tty->count == 1) && (info->count != 1)) {
1301 /*
1302 * Uh, oh. tty->count is 1, which means that the tty
1303 * structure will be freed. Info->count should always
1304 * be one in these conditions. If it's greater than
1305 * one, we've got real problems, since it means the
1306 * serial port won't be shutdown.
1307 */
1308 printk("rs_close: bad serial port count; tty->count is 1, "
1309 "info->count is %d\n", info->count);
1310 info->count = 1;
1311 }
1312 if (--info->count < 0) {
1313 printk("rs_close: bad serial port count for ttyS%d: %d\n",
1314 info->line, info->count);
1315 info->count = 0;
1316 }
1317 if (info->count) {
1318 restore_flags(flags);
1319 return;
1320 }
1321 info->flags |= ZILOG_CLOSING;
1322 /*
1323 * Now we wait for the transmit buffer to clear; and we notify
1324 * the line discipline to only process XON/XOFF characters.
1325 */
1326 tty->closing = 1;
1327 if (info->closing_wait != ZILOG_CLOSING_WAIT_NONE)
1328 tty_wait_until_sent(tty, info->closing_wait);
1329 /*
1330 * At this point we stop accepting input. To do this, we
1331 * disable the receiver and receive interrupts.
1332 */
1333 info->zs_channel->curregs[3] &= ~RxENABLE;
1334 write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
1335 info->zs_channel->curregs[1] = 0; /* disable any rx ints */
1336 write_zsreg(info->zs_channel, 1, info->zs_channel->curregs[1]);
1337 ZS_CLEARFIFO(info->zs_channel);
1338 if (info->flags & ZILOG_INITIALIZED) {
1339 /*
1340 * Before we drop DTR, make sure the SCC transmitter
1341 * has completely drained.
1342 */
1343 rs_wait_until_sent(tty, info->timeout);
1344 }
1345
1346 shutdown(info);
1347 if (tty->driver->flush_buffer)
1348 tty->driver->flush_buffer(tty);
1349 tty_ldisc_flush(tty);
1350 tty->closing = 0;
1351 info->event = 0;
1352 info->tty = 0;
1353 if (info->blocked_open) {
1354 if (info->close_delay) {
1355 msleep_interruptible(jiffies_to_msecs(info->close_delay));
1356 }
1357 wake_up_interruptible(&info->open_wait);
1358 }
1359 info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CLOSING);
1360 wake_up_interruptible(&info->close_wait);
1361 restore_flags(flags);
1362}
1363
1364/*
1365 * rs_wait_until_sent() --- wait until the transmitter is empty
1366 */
1367static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
1368{
1369 struct dec_serial *info = (struct dec_serial *) tty->driver_data;
1370 unsigned long orig_jiffies;
1371 int char_time;
1372
1373 if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
1374 return;
1375
1376 orig_jiffies = jiffies;
1377 /*
1378 * Set the check interval to be 1/5 of the estimated time to
1379 * send a single character, and make it at least 1. The check
1380 * interval should also be less than the timeout.
1381 */
1382 char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
1383 char_time = char_time / 5;
1384 if (char_time == 0)
1385 char_time = 1;
1386 if (timeout)
1387 char_time = min(char_time, timeout);
1388 while ((read_zsreg(info->zs_channel, 1) & Tx_BUF_EMP) == 0) {
1389 msleep_interruptible(jiffies_to_msecs(char_time));
1390 if (signal_pending(current))
1391 break;
1392 if (timeout && time_after(jiffies, orig_jiffies + timeout))
1393 break;
1394 }
1395 current->state = TASK_RUNNING;
1396}
1397
1398/*
1399 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1400 */
1401void rs_hangup(struct tty_struct *tty)
1402{
1403 struct dec_serial * info = (struct dec_serial *)tty->driver_data;
1404
1405 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1406 return;
1407
1408 rs_flush_buffer(tty);
1409 shutdown(info);
1410 info->event = 0;
1411 info->count = 0;
1412 info->flags &= ~ZILOG_NORMAL_ACTIVE;
1413 info->tty = 0;
1414 wake_up_interruptible(&info->open_wait);
1415}
1416
1417/*
1418 * ------------------------------------------------------------
1419 * rs_open() and friends
1420 * ------------------------------------------------------------
1421 */
1422static int block_til_ready(struct tty_struct *tty, struct file * filp,
1423 struct dec_serial *info)
1424{
1425 DECLARE_WAITQUEUE(wait, current);
1426 int retval;
1427 int do_clocal = 0;
1428
1429 /*
1430 * If the device is in the middle of being closed, then block
1431 * until it's done, and then try again.
1432 */
1433 if (info->flags & ZILOG_CLOSING) {
1434 interruptible_sleep_on(&info->close_wait);
1435#ifdef SERIAL_DO_RESTART
1436 return ((info->flags & ZILOG_HUP_NOTIFY) ?
1437 -EAGAIN : -ERESTARTSYS);
1438#else
1439 return -EAGAIN;
1440#endif
1441 }
1442
1443 /*
1444 * If non-blocking mode is set, or the port is not enabled,
1445 * then make the check up front and then exit.
1446 */
1447 if ((filp->f_flags & O_NONBLOCK) ||
1448 (tty->flags & (1 << TTY_IO_ERROR))) {
1449 info->flags |= ZILOG_NORMAL_ACTIVE;
1450 return 0;
1451 }
1452
1453 if (tty->termios->c_cflag & CLOCAL)
1454 do_clocal = 1;
1455
1456 /*
1457 * Block waiting for the carrier detect and the line to become
1458 * free (i.e., not in use by the callout). While we are in
1459 * this loop, info->count is dropped by one, so that
1460 * rs_close() knows when to free things. We restore it upon
1461 * exit, either normal or abnormal.
1462 */
1463 retval = 0;
1464 add_wait_queue(&info->open_wait, &wait);
1465#ifdef SERIAL_DEBUG_OPEN
1466 printk("block_til_ready before block: ttyS%d, count = %d\n",
1467 info->line, info->count);
1468#endif
1469 cli();
1470 if (!tty_hung_up_p(filp))
1471 info->count--;
1472 sti();
1473 info->blocked_open++;
1474 while (1) {
1475 cli();
1476 if (tty->termios->c_cflag & CBAUD)
1477 zs_rtsdtr(info, RTS | DTR, 1);
1478 sti();
1479 set_current_state(TASK_INTERRUPTIBLE);
1480 if (tty_hung_up_p(filp) ||
1481 !(info->flags & ZILOG_INITIALIZED)) {
1482#ifdef SERIAL_DO_RESTART
1483 if (info->flags & ZILOG_HUP_NOTIFY)
1484 retval = -EAGAIN;
1485 else
1486 retval = -ERESTARTSYS;
1487#else
1488 retval = -EAGAIN;
1489#endif
1490 break;
1491 }
1492 if (!(info->flags & ZILOG_CLOSING) &&
1493 (do_clocal || (read_zsreg(info->zs_channel, 0) & DCD)))
1494 break;
1495 if (signal_pending(current)) {
1496 retval = -ERESTARTSYS;
1497 break;
1498 }
1499#ifdef SERIAL_DEBUG_OPEN
1500 printk("block_til_ready blocking: ttyS%d, count = %d\n",
1501 info->line, info->count);
1502#endif
1503 schedule();
1504 }
1505 current->state = TASK_RUNNING;
1506 remove_wait_queue(&info->open_wait, &wait);
1507 if (!tty_hung_up_p(filp))
1508 info->count++;
1509 info->blocked_open--;
1510#ifdef SERIAL_DEBUG_OPEN
1511 printk("block_til_ready after blocking: ttyS%d, count = %d\n",
1512 info->line, info->count);
1513#endif
1514 if (retval)
1515 return retval;
1516 info->flags |= ZILOG_NORMAL_ACTIVE;
1517 return 0;
1518}
1519
1520/*
1521 * This routine is called whenever a serial port is opened. It
1522 * enables interrupts for a serial port, linking in its ZILOG structure into
1523 * the IRQ chain. It also performs the serial-specific
1524 * initialization for the tty structure.
1525 */
1526int rs_open(struct tty_struct *tty, struct file * filp)
1527{
1528 struct dec_serial *info;
1529 int retval, line;
1530
1531 line = tty->index;
1532 if ((line < 0) || (line >= zs_channels_found))
1533 return -ENODEV;
1534 info = zs_soft + line;
1535
1536 if (info->hook)
1537 return -ENODEV;
1538
1539 if (serial_paranoia_check(info, tty->name, "rs_open"))
1540 return -ENODEV;
1541#ifdef SERIAL_DEBUG_OPEN
1542 printk("rs_open %s, count = %d\n", tty->name, info->count);
1543#endif
1544
1545 info->count++;
1546 tty->driver_data = info;
1547 info->tty = tty;
1548
1549 /*
1550 * If the port is the middle of closing, bail out now
1551 */
1552 if (tty_hung_up_p(filp) ||
1553 (info->flags & ZILOG_CLOSING)) {
1554 if (info->flags & ZILOG_CLOSING)
1555 interruptible_sleep_on(&info->close_wait);
1556#ifdef SERIAL_DO_RESTART
1557 return ((info->flags & ZILOG_HUP_NOTIFY) ?
1558 -EAGAIN : -ERESTARTSYS);
1559#else
1560 return -EAGAIN;
1561#endif
1562 }
1563
1564 /*
1565 * Start up serial port
1566 */
1567 retval = zs_startup(info);
1568 if (retval)
1569 return retval;
1570
1571 retval = block_til_ready(tty, filp, info);
1572 if (retval) {
1573#ifdef SERIAL_DEBUG_OPEN
1574 printk("rs_open returning after block_til_ready with %d\n",
1575 retval);
1576#endif
1577 return retval;
1578 }
1579
1580#ifdef CONFIG_SERIAL_DEC_CONSOLE
1581 if (sercons.cflag && sercons.index == line) {
1582 tty->termios->c_cflag = sercons.cflag;
1583 sercons.cflag = 0;
1584 change_speed(info);
1585 }
1586#endif
1587
1588#ifdef SERIAL_DEBUG_OPEN
1589 printk("rs_open %s successful...", tty->name);
1590#endif
1591/* tty->low_latency = 1; */
1592 return 0;
1593}
1594
1595/* Finally, routines used to initialize the serial driver. */
1596
1597static void __init show_serial_version(void)
1598{
1599 printk("DECstation Z8530 serial driver version 0.09\n");
1600}
1601
1602/* Initialize Z8530s zs_channels
1603 */
1604
1605static void __init probe_sccs(void)
1606{
1607 struct dec_serial **pp;
1608 int i, n, n_chips = 0, n_channels, chip, channel;
1609 unsigned long flags;
1610
1611 /*
1612 * did we get here by accident?
1613 */
1614 if(!BUS_PRESENT) {
1615 printk("Not on JUNKIO machine, skipping probe_sccs\n");
1616 return;
1617 }
1618
1da177e4
LT		 1619 switch(mips_machtype) {
1620#ifdef CONFIG_MACH_DECSTATION
1621 case MACH_DS5000_2X0:
1622 case MACH_DS5900:
1da177e4
LT		 1623 n_chips = 2;
1624 zs_parms = &ds_parms;
1625 zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
1626 zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
1627 break;
1628 case MACH_DS5000_1XX:
1da177e4
LT		 1629 n_chips = 2;
1630 zs_parms = &ds_parms;
1631 zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
1632 zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
1633 break;
1634 case MACH_DS5000_XX:
1da177e4
LT		 1635 n_chips = 1;
1636 zs_parms = &ds_parms;
1637 zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
1638 break;
1639#endif
1640 default:
1641 panic("zs: unsupported bus");
1642 }
1643 if (!zs_parms)
1644 panic("zs: uninitialized parms");
1645
1646 pp = &zs_chain;
1647
1648 n_channels = 0;
1649
1650 for (chip = 0; chip < n_chips; chip++) {
1651 for (channel = 0; channel <= 1; channel++) {
1652 /*
1653 * The sccs reside on the high byte of the 16 bit IOBUS
1654 */
1655 zs_channels[n_channels].control =
a5fc9c0b 1656 (volatile void *)CKSEG1ADDR(dec_kn_slot_base +
1da177e4
LT		 1657 (0 == chip ? zs_parms->scc0 : zs_parms->scc1) +
1658 (0 == channel ? zs_parms->channel_a_offset :
a5fc9c0b 1659 zs_parms->channel_b_offset));
1da177e4
LT		 1660 zs_channels[n_channels].data =
1661 zs_channels[n_channels].control + 4;
1662
1663#ifndef CONFIG_SERIAL_DEC_CONSOLE
1664 /*
1665 * We're called early and memory managment isn't up, yet.
fb911ee8 1666 * Thus request_region would fail.
1da177e4
LT		 1667 */
1668 if (!request_region((unsigned long)
1669 zs_channels[n_channels].control,
1670 ZS_CHAN_IO_SIZE, "SCC"))
1671 panic("SCC I/O region is not free");
1672#endif
1673 zs_soft[n_channels].zs_channel = &zs_channels[n_channels];
1674 /* HACK alert! */
1675 if (!(chip & 1))
1676 zs_soft[n_channels].irq = zs_parms->irq0;
1677 else
1678 zs_soft[n_channels].irq = zs_parms->irq1;
1679
1680 /*
1681 * Identification of channel A. Location of channel A
1682 * inside chip depends on mapping of internal address
1683 * the chip decodes channels by.
1684 * CHANNEL_A_NR returns either 0 (in case of
1685 * DECstations) or 1 (in case of Baget).
1686 */
1687 if (CHANNEL_A_NR == channel)
1688 zs_soft[n_channels].zs_chan_a =
1689 &zs_channels[n_channels+1-2*CHANNEL_A_NR];
1690 else
1691 zs_soft[n_channels].zs_chan_a =
1692 &zs_channels[n_channels];
1693
1694 *pp = &zs_soft[n_channels];
1695 pp = &zs_soft[n_channels].zs_next;
1696 n_channels++;
1697 }
1698 }
1699
1700 *pp = 0;
1701 zs_channels_found = n_channels;
1702
1703 for (n = 0; n < zs_channels_found; n++) {
1704 for (i = 0; i < 16; i++) {
1705 zs_soft[n].zs_channel->curregs[i] = zs_init_regs[i];
1706 }
1707 }
1708
1709 save_and_cli(flags);
1710 for (n = 0; n < zs_channels_found; n++) {
1711 if (n % 2 == 0) {
1712 write_zsreg(zs_soft[n].zs_chan_a, R9, FHWRES);
1713 udelay(10);
1714 write_zsreg(zs_soft[n].zs_chan_a, R9, 0);
1715 }
1716 load_zsregs(zs_soft[n].zs_channel,
1717 zs_soft[n].zs_channel->curregs);
1718 }
1719 restore_flags(flags);
1720}
1721
1722static struct tty_operations serial_ops = {
1723 .open = rs_open,
1724 .close = rs_close,
1725 .write = rs_write,
1726 .flush_chars = rs_flush_chars,
1727 .write_room = rs_write_room,
1728 .chars_in_buffer = rs_chars_in_buffer,
1729 .flush_buffer = rs_flush_buffer,
1730 .ioctl = rs_ioctl,
1731 .throttle = rs_throttle,
1732 .unthrottle = rs_unthrottle,
1733 .set_termios = rs_set_termios,
1734 .stop = rs_stop,
1735 .start = rs_start,
1736 .hangup = rs_hangup,
1737 .break_ctl = rs_break,
1738 .wait_until_sent = rs_wait_until_sent,
1739 .tiocmget = rs_tiocmget,
1740 .tiocmset = rs_tiocmset,
1741};
1742
1743/* zs_init inits the driver */
1744int __init zs_init(void)
1745{
1746 int channel, i;
1747 struct dec_serial *info;
1748
1749 if(!BUS_PRESENT)
1750 return -ENODEV;
1751
1752 /* Setup base handler, and timer table. */
1753 init_bh(SERIAL_BH, do_serial_bh);
1754
1755 /* Find out how many Z8530 SCCs we have */
1756 if (zs_chain == 0)
1757 probe_sccs();
1758 serial_driver = alloc_tty_driver(zs_channels_found);
1759 if (!serial_driver)
1760 return -ENOMEM;
1761
1762 show_serial_version();
1763
1764 /* Initialize the tty_driver structure */
1765 /* Not all of this is exactly right for us. */
1766
1767 serial_driver->owner = THIS_MODULE;
1768 serial_driver->devfs_name = "tts/";
1769 serial_driver->name = "ttyS";
1770 serial_driver->major = TTY_MAJOR;
1771 serial_driver->minor_start = 64;
1772 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1773 serial_driver->subtype = SERIAL_TYPE_NORMAL;
1774 serial_driver->init_termios = tty_std_termios;
1775 serial_driver->init_termios.c_cflag =
1776 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1777 serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS;
1778 tty_set_operations(serial_driver, &serial_ops);
1779
1780 if (tty_register_driver(serial_driver))
1781 panic("Couldn't register serial driver");
1782
1783 for (info = zs_chain, i = 0; info; info = info->zs_next, i++) {
1784
1785 /* Needed before interrupts are enabled. */
1786 info->tty = 0;
1787 info->x_char = 0;
1788
1789 if (info->hook && info->hook->init_info) {
1790 (*info->hook->init_info)(info);
1791 continue;
1792 }
1793
1794 info->magic = SERIAL_MAGIC;
1795 info->port = (int) info->zs_channel->control;
1796 info->line = i;
1797 info->custom_divisor = 16;
1798 info->close_delay = 50;
1799 info->closing_wait = 3000;
1800 info->event = 0;
1801 info->count = 0;
1802 info->blocked_open = 0;
1803 info->tqueue.routine = do_softint;
1804 info->tqueue.data = info;
1805 init_waitqueue_head(&info->open_wait);
1806 init_waitqueue_head(&info->close_wait);
1807 printk("ttyS%02d at 0x%08x (irq = %d) is a Z85C30 SCC\n",
1808 info->line, info->port, info->irq);
1809 tty_register_device(serial_driver, info->line, NULL);
1810
1811 }
1812
1813 for (channel = 0; channel < zs_channels_found; ++channel) {
1814 zs_soft[channel].clk_divisor = 16;
1815 zs_soft[channel].zs_baud = get_zsbaud(&zs_soft[channel]);
1816
1817 if (request_irq(zs_soft[channel].irq, rs_interrupt, SA_SHIRQ,
1818 "scc", &zs_soft[channel]))
1819 printk(KERN_ERR "decserial: can't get irq %d\n",
1820 zs_soft[channel].irq);
1821
1822 if (zs_soft[channel].hook) {
1823 zs_startup(&zs_soft[channel]);
1824 if (zs_soft[channel].hook->init_channel)
1825 (*zs_soft[channel].hook->init_channel)
1826 (&zs_soft[channel]);
1827 }
1828 }
1829
1830 return 0;
1831}
1832
1833/*
1834 * polling I/O routines
1835 */
1836static int
1837zs_poll_tx_char(void *handle, unsigned char ch)
1838{
1839 struct dec_serial *info = handle;
1840 struct dec_zschannel *chan = info->zs_channel;
1841 int ret;
1842
1843 if(chan) {
1844 int loops = 10000;
1845
1846 while (loops && !(read_zsreg(chan, 0) & Tx_BUF_EMP))
1847 loops--;
1848
1849 if (loops) {
1850 write_zsdata(chan, ch);
1851 ret = 0;
1852 } else
1853 ret = -EAGAIN;
1854
1855 return ret;
1856 } else
1857 return -ENODEV;
1858}
1859
1860static int
1861zs_poll_rx_char(void *handle)
1862{
1863 struct dec_serial *info = handle;
1864 struct dec_zschannel *chan = info->zs_channel;
1865 int ret;
1866
1867 if(chan) {
1868 int loops = 10000;
1869
1870 while (loops && !(read_zsreg(chan, 0) & Rx_CH_AV))
1871 loops--;
1872
1873 if (loops)
1874 ret = read_zsdata(chan);
1875 else
1876 ret = -EAGAIN;
1877
1878 return ret;
1879 } else
1880 return -ENODEV;
1881}
1882
1883int register_zs_hook(unsigned int channel, struct dec_serial_hook *hook)
1884{
1885 struct dec_serial *info = &zs_soft[channel];
1886
1887 if (info->hook) {
1888 printk("%s: line %d has already a hook registered\n",
1889 __FUNCTION__, channel);
1890
1891 return 0;
1892 } else {
1893 hook->poll_rx_char = zs_poll_rx_char;
1894 hook->poll_tx_char = zs_poll_tx_char;
1895 info->hook = hook;
1896
1897 return 1;
1898 }
1899}
1900
1901int unregister_zs_hook(unsigned int channel)
1902{
1903 struct dec_serial *info = &zs_soft[channel];
1904
1905 if (info->hook) {
1906 info->hook = NULL;
1907 return 1;
1908 } else {
1909 printk("%s: trying to unregister hook on line %d,"
1910 " but none is registered\n", __FUNCTION__, channel);
1911 return 0;
1912 }
1913}
1914
1915/*
1916 * ------------------------------------------------------------
1917 * Serial console driver
1918 * ------------------------------------------------------------
1919 */
1920#ifdef CONFIG_SERIAL_DEC_CONSOLE
1921
1922
1923/*
1924 * Print a string to the serial port trying not to disturb
1925 * any possible real use of the port...
1926 */
1927static void serial_console_write(struct console *co, const char *s,
1928 unsigned count)
1929{
1930 struct dec_serial *info;
1931 int i;
1932
1933 info = zs_soft + co->index;
1934
1935 for (i = 0; i < count; i++, s++) {
1936 if(*s == '\n')
1937 zs_poll_tx_char(info, '\r');
1938 zs_poll_tx_char(info, *s);
1939 }
1940}
1941
1942static struct tty_driver *serial_console_device(struct console *c, int *index)
1943{
1944 *index = c->index;
1945 return serial_driver;
1946}
1947
1948/*
1949 * Setup initial baud/bits/parity. We do two things here:
1950 * - construct a cflag setting for the first rs_open()
1951 * - initialize the serial port
1952 * Return non-zero if we didn't find a serial port.
1953 */
1954static int __init serial_console_setup(struct console *co, char *options)
1955{
1956 struct dec_serial *info;
1957 int baud = 9600;
1958 int bits = 8;
1959 int parity = 'n';
1960 int cflag = CREAD | HUPCL | CLOCAL;
1961 int clk_divisor = 16;
1962 int brg;
1963 char *s;
1964 unsigned long flags;
1965
1966 if(!BUS_PRESENT)
1967 return -ENODEV;
1968
1969 info = zs_soft + co->index;
1970
1971 if (zs_chain == 0)
1972 probe_sccs();
1973
1974 info->is_cons = 1;
1975
1976 if (options) {
1977 baud = simple_strtoul(options, NULL, 10);
1978 s = options;
1979 while(*s >= '0' && *s <= '9')
1980 s++;
1981 if (*s)
1982 parity = *s++;
1983 if (*s)
1984 bits = *s - '0';
1985 }
1986
1987 /*
1988 * Now construct a cflag setting.
1989 */
1990 switch(baud) {
1991 case 1200:
1992 cflag |= B1200;
1993 break;
1994 case 2400:
1995 cflag |= B2400;
1996 break;
1997 case 4800:
1998 cflag |= B4800;
1999 break;
2000 case 19200:
2001 cflag |= B19200;
2002 break;
2003 case 38400:
2004 cflag |= B38400;
2005 break;
2006 case 57600:
2007 cflag |= B57600;
2008 break;
2009 case 115200:
2010 cflag |= B115200;
2011 break;
2012 case 9600:
2013 default:
2014 cflag |= B9600;
2015 /*
2016 * Set this to a sane value to prevent a divide error.
2017 */
2018 baud = 9600;
2019 break;
2020 }
2021 switch(bits) {
2022 case 7:
2023 cflag |= CS7;
2024 break;
2025 default:
2026 case 8:
2027 cflag |= CS8;
2028 break;
2029 }
2030 switch(parity) {
2031 case 'o': case 'O':
2032 cflag |= PARODD;
2033 break;
2034 case 'e': case 'E':
2035 cflag |= PARENB;
2036 break;
2037 }
2038 co->cflag = cflag;
2039
2040 save_and_cli(flags);
2041
2042 /*
2043 * Set up the baud rate generator.
2044 */
2045 brg = BPS_TO_BRG(baud, zs_parms->clock / clk_divisor);
2046 info->zs_channel->curregs[R12] = (brg & 255);
2047 info->zs_channel->curregs[R13] = ((brg >> 8) & 255);
2048
2049 /*
2050 * Set byte size and parity.
2051 */
2052 if (bits == 7) {
2053 info->zs_channel->curregs[R3] |= Rx7;
2054 info->zs_channel->curregs[R5] |= Tx7;
2055 } else {
2056 info->zs_channel->curregs[R3] |= Rx8;
2057 info->zs_channel->curregs[R5] |= Tx8;
2058 }
2059 if (cflag & PARENB) {
2060 info->zs_channel->curregs[R4] |= PAR_ENA;
2061 }
2062 if (!(cflag & PARODD)) {
2063 info->zs_channel->curregs[R4] |= PAR_EVEN;
2064 }
2065 info->zs_channel->curregs[R4] |= SB1;
2066
2067 /*
2068 * Turn on RTS and DTR.
2069 */
2070 zs_rtsdtr(info, RTS | DTR, 1);
2071
2072 /*
2073 * Finally, enable sequencing.
2074 */
2075 info->zs_channel->curregs[R3] |= RxENABLE;
2076 info->zs_channel->curregs[R5] |= TxENAB;
2077
2078 /*
2079 * Clear the interrupt registers.
2080 */
2081 write_zsreg(info->zs_channel, R0, ERR_RES);
2082 write_zsreg(info->zs_channel, R0, RES_H_IUS);
2083
2084 /*
2085 * Load up the new values.
2086 */
2087 load_zsregs(info->zs_channel, info->zs_channel->curregs);
2088
2089 /* Save the current value of RR0 */
2090 info->read_reg_zero = read_zsreg(info->zs_channel, R0);
2091
2092 zs_soft[co->index].clk_divisor = clk_divisor;
2093 zs_soft[co->index].zs_baud = get_zsbaud(&zs_soft[co->index]);
2094
2095 restore_flags(flags);
2096
2097 return 0;
2098}
2099
2100static struct console sercons = {
2101 .name = "ttyS",
2102 .write = serial_console_write,
2103 .device = serial_console_device,
2104 .setup = serial_console_setup,
2105 .flags = CON_PRINTBUFFER,
2106 .index = -1,
2107};
2108
2109/*
2110 * Register console.
2111 */
2112void __init zs_serial_console_init(void)
2113{
2114 register_console(&sercons);
2115}
2116#endif /* ifdef CONFIG_SERIAL_DEC_CONSOLE */
2117
2118#ifdef CONFIG_KGDB
2119struct dec_zschannel *zs_kgdbchan;
2120static unsigned char scc_inittab[] = {
2121 9, 0x80, /* reset A side (CHRA) */
2122 13, 0, /* set baud rate divisor */
2123 12, 1,
2124 14, 1, /* baud rate gen enable, src=rtxc (BRENABL) */
2125 11, 0x50, /* clocks = br gen (RCBR | TCBR) */
2126 5, 0x6a, /* tx 8 bits, assert RTS (Tx8 | TxENAB | RTS) */
2127 4, 0x44, /* x16 clock, 1 stop (SB1 | X16CLK)*/
2128 3, 0xc1, /* rx enable, 8 bits (RxENABLE | Rx8)*/
2129};
2130
2131/* These are for receiving and sending characters under the kgdb
2132 * source level kernel debugger.
2133 */
2134void putDebugChar(char kgdb_char)
2135{
2136 struct dec_zschannel *chan = zs_kgdbchan;
2137 while ((read_zsreg(chan, 0) & Tx_BUF_EMP) == 0)
2138 RECOVERY_DELAY;
2139 write_zsdata(chan, kgdb_char);
2140}
2141char getDebugChar(void)
2142{
2143 struct dec_zschannel *chan = zs_kgdbchan;
2144 while((read_zsreg(chan, 0) & Rx_CH_AV) == 0)
2145 eieio(); /*barrier();*/
2146 return read_zsdata(chan);
2147}
2148void kgdb_interruptible(int yes)
2149{
2150 struct dec_zschannel *chan = zs_kgdbchan;
2151 int one, nine;
2152 nine = read_zsreg(chan, 9);
2153 if (yes == 1) {
2154 one = EXT_INT_ENAB|RxINT_ALL;
2155 nine |= MIE;
2156 printk("turning serial ints on\n");
2157 } else {
2158 one = RxINT_DISAB;
2159 nine &= ~MIE;
2160 printk("turning serial ints off\n");
2161 }
2162 write_zsreg(chan, 1, one);
2163 write_zsreg(chan, 9, nine);
2164}
2165
2166static int kgdbhook_init_channel(void *handle)
2167{
2168 return 0;
2169}
2170
2171static void kgdbhook_init_info(void *handle)
2172{
2173}
2174
2175static void kgdbhook_rx_char(void *handle, unsigned char ch, unsigned char fl)
2176{
2177 struct dec_serial *info = handle;
2178
2179 if (fl != TTY_NORMAL)
2180 return;
2181 if (ch == 0x03 || ch == '$')
2182 breakpoint();
2183}
2184
2185/* This sets up the serial port we're using, and turns on
2186 * interrupts for that channel, so kgdb is usable once we're done.
2187 */
2188static inline void kgdb_chaninit(struct dec_zschannel *ms, int intson, int bps)
2189{
2190 int brg;
2191 int i, x;
2192 volatile char *sccc = ms->control;
2193 brg = BPS_TO_BRG(bps, zs_parms->clock/16);
2194 printk("setting bps on kgdb line to %d [brg=%x]\n", bps, brg);
2195 for (i = 20000; i != 0; --i) {
2196 x = *sccc; eieio();
2197 }
2198 for (i = 0; i < sizeof(scc_inittab); ++i) {
2199 write_zsreg(ms, scc_inittab[i], scc_inittab[i+1]);
2200 i++;
2201 }
2202}
2203/* This is called at boot time to prime the kgdb serial debugging
2204 * serial line. The 'tty_num' argument is 0 for /dev/ttya and 1
2205 * for /dev/ttyb which is determined in setup_arch() from the
2206 * boot command line flags.
2207 */
2208struct dec_serial_hook zs_kgdbhook = {
2209 .init_channel = kgdbhook_init_channel,
2210 .init_info = kgdbhook_init_info,
2211 .rx_char = kgdbhook_rx_char,
2212 .cflags = B38400 | CS8 | CLOCAL,
2213}
2214
2215void __init zs_kgdb_hook(int tty_num)
2216{
2217 /* Find out how many Z8530 SCCs we have */
2218 if (zs_chain == 0)
2219 probe_sccs();
2220 zs_soft[tty_num].zs_channel = &zs_channels[tty_num];
2221 zs_kgdbchan = zs_soft[tty_num].zs_channel;
2222 zs_soft[tty_num].change_needed = 0;
2223 zs_soft[tty_num].clk_divisor = 16;
2224 zs_soft[tty_num].zs_baud = 38400;
2225 zs_soft[tty_num].hook = &zs_kgdbhook; /* This runs kgdb */
2226 /* Turn on transmitter/receiver at 8-bits/char */
2227 kgdb_chaninit(zs_soft[tty_num].zs_channel, 1, 38400);
2228 printk("KGDB: on channel %d initialized\n", tty_num);
2229 set_debug_traps(); /* init stub */
2230}
2231#endif /* ifdef CONFIG_KGDB */
2232
2233
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