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v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * dz.c: Serial port driver for DECstations equipped
  4 *       with the DZ chipset.
  5 *
  6 * Copyright (C) 1998 Olivier A. D. Lebaillif
  7 *
  8 * Email: olivier.lebaillif@ifrsys.com
  9 *
 10 * Copyright (C) 2004, 2006, 2007  Maciej W. Rozycki
 11 *
 12 * [31-AUG-98] triemer
 13 * Changed IRQ to use Harald's dec internals interrupts.h
 14 * removed base_addr code - moving address assignment to setup.c
 15 * Changed name of dz_init to rs_init to be consistent with tc code
 16 * [13-NOV-98] triemer fixed code to receive characters
 17 *    after patches by harald to irq code.
 18 * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout
 19 *            field from "current" - somewhere between 2.1.121 and 2.1.131
 20 Qua Jun 27 15:02:26 BRT 2001
 21 * [27-JUN-2001] Arnaldo Carvalho de Melo <acme@conectiva.com.br> - cleanups
 22 *
 23 * Parts (C) 1999 David Airlie, airlied@linux.ie
 24 * [07-SEP-99] Bugfixes
 25 *
 26 * [06-Jan-2002] Russell King <rmk@arm.linux.org.uk>
 27 * Converted to new serial core
 28 */
 29
 30#undef DEBUG_DZ
 31
 32#if defined(CONFIG_SERIAL_DZ_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 33#define SUPPORT_SYSRQ
 34#endif
 35
 36#include <linux/bitops.h>
 37#include <linux/compiler.h>
 38#include <linux/console.h>
 39#include <linux/delay.h>
 40#include <linux/errno.h>
 41#include <linux/init.h>
 42#include <linux/interrupt.h>
 43#include <linux/ioport.h>
 44#include <linux/kernel.h>
 45#include <linux/major.h>
 46#include <linux/module.h>
 47#include <linux/serial.h>
 48#include <linux/serial_core.h>
 49#include <linux/sysrq.h>
 50#include <linux/tty.h>
 51#include <linux/tty_flip.h>
 52
 53#include <linux/atomic.h>
 54#include <asm/bootinfo.h>
 55#include <asm/io.h>
 56
 57#include <asm/dec/interrupts.h>
 58#include <asm/dec/kn01.h>
 59#include <asm/dec/kn02.h>
 60#include <asm/dec/machtype.h>
 61#include <asm/dec/prom.h>
 62#include <asm/dec/system.h>
 63
 64#include "dz.h"
 65
 66
 67MODULE_DESCRIPTION("DECstation DZ serial driver");
 68MODULE_LICENSE("GPL");
 69
 70
 71static char dz_name[] __initdata = "DECstation DZ serial driver version ";
 72static char dz_version[] __initdata = "1.04";
 73
 74struct dz_port {
 75	struct dz_mux		*mux;
 76	struct uart_port	port;
 77	unsigned int		cflag;
 78};
 79
 80struct dz_mux {
 81	struct dz_port		dport[DZ_NB_PORT];
 82	atomic_t		map_guard;
 83	atomic_t		irq_guard;
 84	int			initialised;
 85};
 86
 87static struct dz_mux dz_mux;
 88
 89static inline struct dz_port *to_dport(struct uart_port *uport)
 90{
 91	return container_of(uport, struct dz_port, port);
 92}
 93
 94/*
 95 * ------------------------------------------------------------
 96 * dz_in () and dz_out ()
 97 *
 98 * These routines are used to access the registers of the DZ
 99 * chip, hiding relocation differences between implementation.
100 * ------------------------------------------------------------
101 */
102
103static u16 dz_in(struct dz_port *dport, unsigned offset)
104{
105	void __iomem *addr = dport->port.membase + offset;
106
107	return readw(addr);
108}
109
110static void dz_out(struct dz_port *dport, unsigned offset, u16 value)
111{
112	void __iomem *addr = dport->port.membase + offset;
113
114	writew(value, addr);
115}
116
117/*
118 * ------------------------------------------------------------
119 * rs_stop () and rs_start ()
120 *
121 * These routines are called before setting or resetting
122 * tty->stopped. They enable or disable transmitter interrupts,
123 * as necessary.
124 * ------------------------------------------------------------
125 */
126
127static void dz_stop_tx(struct uart_port *uport)
128{
129	struct dz_port *dport = to_dport(uport);
130	u16 tmp, mask = 1 << dport->port.line;
131
132	tmp = dz_in(dport, DZ_TCR);	/* read the TX flag */
133	tmp &= ~mask;			/* clear the TX flag */
134	dz_out(dport, DZ_TCR, tmp);
135}
136
137static void dz_start_tx(struct uart_port *uport)
138{
139	struct dz_port *dport = to_dport(uport);
140	u16 tmp, mask = 1 << dport->port.line;
141
142	tmp = dz_in(dport, DZ_TCR);	/* read the TX flag */
143	tmp |= mask;			/* set the TX flag */
144	dz_out(dport, DZ_TCR, tmp);
145}
146
147static void dz_stop_rx(struct uart_port *uport)
148{
149	struct dz_port *dport = to_dport(uport);
150
151	dport->cflag &= ~DZ_RXENAB;
152	dz_out(dport, DZ_LPR, dport->cflag);
153}
154
 
 
 
 
 
155/*
156 * ------------------------------------------------------------
157 *
158 * Here start the interrupt handling routines.  All of the following
159 * subroutines are declared as inline and are folded into
160 * dz_interrupt.  They were separated out for readability's sake.
161 *
162 * Note: dz_interrupt() is a "fast" interrupt, which means that it
163 * runs with interrupts turned off.  People who may want to modify
164 * dz_interrupt() should try to keep the interrupt handler as fast as
165 * possible.  After you are done making modifications, it is not a bad
166 * idea to do:
167 *
168 *	make drivers/serial/dz.s
169 *
170 * and look at the resulting assemble code in dz.s.
171 *
172 * ------------------------------------------------------------
173 */
174
175/*
176 * ------------------------------------------------------------
177 * receive_char ()
178 *
179 * This routine deals with inputs from any lines.
180 * ------------------------------------------------------------
181 */
182static inline void dz_receive_chars(struct dz_mux *mux)
183{
184	struct uart_port *uport;
185	struct dz_port *dport = &mux->dport[0];
186	struct uart_icount *icount;
187	int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
188	unsigned char ch, flag;
189	u16 status;
190	int i;
191
192	while ((status = dz_in(dport, DZ_RBUF)) & DZ_DVAL) {
193		dport = &mux->dport[LINE(status)];
194		uport = &dport->port;
195
196		ch = UCHAR(status);		/* grab the char */
197		flag = TTY_NORMAL;
198
199		icount = &uport->icount;
200		icount->rx++;
201
202		if (unlikely(status & (DZ_OERR | DZ_FERR | DZ_PERR))) {
203
204			/*
205			 * There is no separate BREAK status bit, so treat
206			 * null characters with framing errors as BREAKs;
207			 * normally, otherwise.  For this move the Framing
208			 * Error bit to a simulated BREAK bit.
209			 */
210			if (!ch) {
211				status |= (status & DZ_FERR) >>
212					  (ffs(DZ_FERR) - ffs(DZ_BREAK));
213				status &= ~DZ_FERR;
214			}
215
216			/* Handle SysRq/SAK & keep track of the statistics. */
217			if (status & DZ_BREAK) {
218				icount->brk++;
219				if (uart_handle_break(uport))
220					continue;
221			} else if (status & DZ_FERR)
222				icount->frame++;
223			else if (status & DZ_PERR)
224				icount->parity++;
225			if (status & DZ_OERR)
226				icount->overrun++;
227
228			status &= uport->read_status_mask;
229			if (status & DZ_BREAK)
230				flag = TTY_BREAK;
231			else if (status & DZ_FERR)
232				flag = TTY_FRAME;
233			else if (status & DZ_PERR)
234				flag = TTY_PARITY;
235
236		}
237
238		if (uart_handle_sysrq_char(uport, ch))
239			continue;
240
241		uart_insert_char(uport, status, DZ_OERR, ch, flag);
242		lines_rx[LINE(status)] = 1;
243	}
244	for (i = 0; i < DZ_NB_PORT; i++)
245		if (lines_rx[i])
246			tty_flip_buffer_push(&mux->dport[i].port.state->port);
247}
248
249/*
250 * ------------------------------------------------------------
251 * transmit_char ()
252 *
253 * This routine deals with outputs to any lines.
254 * ------------------------------------------------------------
255 */
256static inline void dz_transmit_chars(struct dz_mux *mux)
257{
258	struct dz_port *dport = &mux->dport[0];
259	struct circ_buf *xmit;
260	unsigned char tmp;
261	u16 status;
262
263	status = dz_in(dport, DZ_CSR);
264	dport = &mux->dport[LINE(status)];
265	xmit = &dport->port.state->xmit;
266
267	if (dport->port.x_char) {		/* XON/XOFF chars */
268		dz_out(dport, DZ_TDR, dport->port.x_char);
269		dport->port.icount.tx++;
270		dport->port.x_char = 0;
271		return;
272	}
273	/* If nothing to do or stopped or hardware stopped. */
274	if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) {
275		spin_lock(&dport->port.lock);
276		dz_stop_tx(&dport->port);
277		spin_unlock(&dport->port.lock);
278		return;
279	}
280
281	/*
282	 * If something to do... (remember the dz has no output fifo,
283	 * so we go one char at a time) :-<
284	 */
285	tmp = xmit->buf[xmit->tail];
286	xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
287	dz_out(dport, DZ_TDR, tmp);
288	dport->port.icount.tx++;
289
290	if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS)
291		uart_write_wakeup(&dport->port);
292
293	/* Are we are done. */
294	if (uart_circ_empty(xmit)) {
295		spin_lock(&dport->port.lock);
296		dz_stop_tx(&dport->port);
297		spin_unlock(&dport->port.lock);
298	}
299}
300
301/*
302 * ------------------------------------------------------------
303 * check_modem_status()
304 *
305 * DS 3100 & 5100: Only valid for the MODEM line, duh!
306 * DS 5000/200: Valid for the MODEM and PRINTER line.
307 * ------------------------------------------------------------
308 */
309static inline void check_modem_status(struct dz_port *dport)
310{
311	/*
312	 * FIXME:
313	 * 1. No status change interrupt; use a timer.
314	 * 2. Handle the 3100/5000 as appropriate. --macro
315	 */
316	u16 status;
317
318	/* If not the modem line just return.  */
319	if (dport->port.line != DZ_MODEM)
320		return;
321
322	status = dz_in(dport, DZ_MSR);
323
324	/* it's easy, since DSR2 is the only bit in the register */
325	if (status)
326		dport->port.icount.dsr++;
327}
328
329/*
330 * ------------------------------------------------------------
331 * dz_interrupt ()
332 *
333 * this is the main interrupt routine for the DZ chip.
334 * It deals with the multiple ports.
335 * ------------------------------------------------------------
336 */
337static irqreturn_t dz_interrupt(int irq, void *dev_id)
338{
339	struct dz_mux *mux = dev_id;
340	struct dz_port *dport = &mux->dport[0];
341	u16 status;
342
343	/* get the reason why we just got an irq */
344	status = dz_in(dport, DZ_CSR);
345
346	if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE))
347		dz_receive_chars(mux);
348
349	if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE))
350		dz_transmit_chars(mux);
351
352	return IRQ_HANDLED;
353}
354
355/*
356 * -------------------------------------------------------------------
357 * Here ends the DZ interrupt routines.
358 * -------------------------------------------------------------------
359 */
360
361static unsigned int dz_get_mctrl(struct uart_port *uport)
362{
363	/*
364	 * FIXME: Handle the 3100/5000 as appropriate. --macro
365	 */
366	struct dz_port *dport = to_dport(uport);
367	unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
368
369	if (dport->port.line == DZ_MODEM) {
370		if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR)
371			mctrl &= ~TIOCM_DSR;
372	}
373
374	return mctrl;
375}
376
377static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
378{
379	/*
380	 * FIXME: Handle the 3100/5000 as appropriate. --macro
381	 */
382	struct dz_port *dport = to_dport(uport);
383	u16 tmp;
384
385	if (dport->port.line == DZ_MODEM) {
386		tmp = dz_in(dport, DZ_TCR);
387		if (mctrl & TIOCM_DTR)
388			tmp &= ~DZ_MODEM_DTR;
389		else
390			tmp |= DZ_MODEM_DTR;
391		dz_out(dport, DZ_TCR, tmp);
392	}
393}
394
395/*
396 * -------------------------------------------------------------------
397 * startup ()
398 *
399 * various initialization tasks
400 * -------------------------------------------------------------------
401 */
402static int dz_startup(struct uart_port *uport)
403{
404	struct dz_port *dport = to_dport(uport);
405	struct dz_mux *mux = dport->mux;
406	unsigned long flags;
407	int irq_guard;
408	int ret;
409	u16 tmp;
410
411	irq_guard = atomic_add_return(1, &mux->irq_guard);
412	if (irq_guard != 1)
413		return 0;
414
415	ret = request_irq(dport->port.irq, dz_interrupt,
416			  IRQF_SHARED, "dz", mux);
417	if (ret) {
418		atomic_add(-1, &mux->irq_guard);
419		printk(KERN_ERR "dz: Cannot get IRQ %d!\n", dport->port.irq);
420		return ret;
421	}
422
423	spin_lock_irqsave(&dport->port.lock, flags);
424
425	/* Enable interrupts.  */
426	tmp = dz_in(dport, DZ_CSR);
427	tmp |= DZ_RIE | DZ_TIE;
428	dz_out(dport, DZ_CSR, tmp);
429
430	spin_unlock_irqrestore(&dport->port.lock, flags);
431
432	return 0;
433}
434
435/*
436 * -------------------------------------------------------------------
437 * shutdown ()
438 *
439 * This routine will shutdown a serial port; interrupts are disabled, and
440 * DTR is dropped if the hangup on close termio flag is on.
441 * -------------------------------------------------------------------
442 */
443static void dz_shutdown(struct uart_port *uport)
444{
445	struct dz_port *dport = to_dport(uport);
446	struct dz_mux *mux = dport->mux;
447	unsigned long flags;
448	int irq_guard;
449	u16 tmp;
450
451	spin_lock_irqsave(&dport->port.lock, flags);
452	dz_stop_tx(&dport->port);
453	spin_unlock_irqrestore(&dport->port.lock, flags);
454
455	irq_guard = atomic_add_return(-1, &mux->irq_guard);
456	if (!irq_guard) {
457		/* Disable interrupts.  */
458		tmp = dz_in(dport, DZ_CSR);
459		tmp &= ~(DZ_RIE | DZ_TIE);
460		dz_out(dport, DZ_CSR, tmp);
461
462		free_irq(dport->port.irq, mux);
463	}
464}
465
466/*
467 * -------------------------------------------------------------------
468 * dz_tx_empty() -- get the transmitter empty status
469 *
470 * Purpose: Let user call ioctl() to get info when the UART physically
471 *          is emptied.  On bus types like RS485, the transmitter must
472 *          release the bus after transmitting. This must be done when
473 *          the transmit shift register is empty, not be done when the
474 *          transmit holding register is empty.  This functionality
475 *          allows an RS485 driver to be written in user space.
476 * -------------------------------------------------------------------
477 */
478static unsigned int dz_tx_empty(struct uart_port *uport)
479{
480	struct dz_port *dport = to_dport(uport);
481	unsigned short tmp, mask = 1 << dport->port.line;
482
483	tmp = dz_in(dport, DZ_TCR);
484	tmp &= mask;
485
486	return tmp ? 0 : TIOCSER_TEMT;
487}
488
489static void dz_break_ctl(struct uart_port *uport, int break_state)
490{
491	/*
492	 * FIXME: Can't access BREAK bits in TDR easily;
493	 * reuse the code for polled TX. --macro
494	 */
495	struct dz_port *dport = to_dport(uport);
496	unsigned long flags;
497	unsigned short tmp, mask = 1 << dport->port.line;
498
499	spin_lock_irqsave(&uport->lock, flags);
500	tmp = dz_in(dport, DZ_TCR);
501	if (break_state)
502		tmp |= mask;
503	else
504		tmp &= ~mask;
505	dz_out(dport, DZ_TCR, tmp);
506	spin_unlock_irqrestore(&uport->lock, flags);
507}
508
509static int dz_encode_baud_rate(unsigned int baud)
510{
511	switch (baud) {
512	case 50:
513		return DZ_B50;
514	case 75:
515		return DZ_B75;
516	case 110:
517		return DZ_B110;
518	case 134:
519		return DZ_B134;
520	case 150:
521		return DZ_B150;
522	case 300:
523		return DZ_B300;
524	case 600:
525		return DZ_B600;
526	case 1200:
527		return DZ_B1200;
528	case 1800:
529		return DZ_B1800;
530	case 2000:
531		return DZ_B2000;
532	case 2400:
533		return DZ_B2400;
534	case 3600:
535		return DZ_B3600;
536	case 4800:
537		return DZ_B4800;
538	case 7200:
539		return DZ_B7200;
540	case 9600:
541		return DZ_B9600;
542	default:
543		return -1;
544	}
545}
546
547
548static void dz_reset(struct dz_port *dport)
549{
550	struct dz_mux *mux = dport->mux;
551
552	if (mux->initialised)
553		return;
554
555	dz_out(dport, DZ_CSR, DZ_CLR);
556	while (dz_in(dport, DZ_CSR) & DZ_CLR);
557	iob();
558
559	/* Enable scanning.  */
560	dz_out(dport, DZ_CSR, DZ_MSE);
561
562	mux->initialised = 1;
563}
564
565static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
566			   struct ktermios *old_termios)
567{
568	struct dz_port *dport = to_dport(uport);
569	unsigned long flags;
570	unsigned int cflag, baud;
571	int bflag;
572
573	cflag = dport->port.line;
574
575	switch (termios->c_cflag & CSIZE) {
576	case CS5:
577		cflag |= DZ_CS5;
578		break;
579	case CS6:
580		cflag |= DZ_CS6;
581		break;
582	case CS7:
583		cflag |= DZ_CS7;
584		break;
585	case CS8:
586	default:
587		cflag |= DZ_CS8;
588	}
589
590	if (termios->c_cflag & CSTOPB)
591		cflag |= DZ_CSTOPB;
592	if (termios->c_cflag & PARENB)
593		cflag |= DZ_PARENB;
594	if (termios->c_cflag & PARODD)
595		cflag |= DZ_PARODD;
596
597	baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600);
598	bflag = dz_encode_baud_rate(baud);
599	if (bflag < 0)	{			/* Try to keep unchanged.  */
600		baud = uart_get_baud_rate(uport, old_termios, NULL, 50, 9600);
601		bflag = dz_encode_baud_rate(baud);
602		if (bflag < 0)	{		/* Resort to 9600.  */
603			baud = 9600;
604			bflag = DZ_B9600;
605		}
606		tty_termios_encode_baud_rate(termios, baud, baud);
607	}
608	cflag |= bflag;
609
610	if (termios->c_cflag & CREAD)
611		cflag |= DZ_RXENAB;
612
613	spin_lock_irqsave(&dport->port.lock, flags);
614
615	uart_update_timeout(uport, termios->c_cflag, baud);
616
617	dz_out(dport, DZ_LPR, cflag);
618	dport->cflag = cflag;
619
620	/* setup accept flag */
621	dport->port.read_status_mask = DZ_OERR;
622	if (termios->c_iflag & INPCK)
623		dport->port.read_status_mask |= DZ_FERR | DZ_PERR;
624	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
625		dport->port.read_status_mask |= DZ_BREAK;
626
627	/* characters to ignore */
628	uport->ignore_status_mask = 0;
629	if ((termios->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
630		dport->port.ignore_status_mask |= DZ_OERR;
631	if (termios->c_iflag & IGNPAR)
632		dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR;
633	if (termios->c_iflag & IGNBRK)
634		dport->port.ignore_status_mask |= DZ_BREAK;
635
636	spin_unlock_irqrestore(&dport->port.lock, flags);
637}
638
639/*
640 * Hack alert!
641 * Required solely so that the initial PROM-based console
642 * works undisturbed in parallel with this one.
643 */
644static void dz_pm(struct uart_port *uport, unsigned int state,
645		  unsigned int oldstate)
646{
647	struct dz_port *dport = to_dport(uport);
648	unsigned long flags;
649
650	spin_lock_irqsave(&dport->port.lock, flags);
651	if (state < 3)
652		dz_start_tx(&dport->port);
653	else
654		dz_stop_tx(&dport->port);
655	spin_unlock_irqrestore(&dport->port.lock, flags);
656}
657
658
659static const char *dz_type(struct uart_port *uport)
660{
661	return "DZ";
662}
663
664static void dz_release_port(struct uart_port *uport)
665{
666	struct dz_mux *mux = to_dport(uport)->mux;
667	int map_guard;
668
669	iounmap(uport->membase);
670	uport->membase = NULL;
671
672	map_guard = atomic_add_return(-1, &mux->map_guard);
673	if (!map_guard)
674		release_mem_region(uport->mapbase, dec_kn_slot_size);
675}
676
677static int dz_map_port(struct uart_port *uport)
678{
679	if (!uport->membase)
680		uport->membase = ioremap_nocache(uport->mapbase,
681						 dec_kn_slot_size);
682	if (!uport->membase) {
683		printk(KERN_ERR "dz: Cannot map MMIO\n");
684		return -ENOMEM;
685	}
686	return 0;
687}
688
689static int dz_request_port(struct uart_port *uport)
690{
691	struct dz_mux *mux = to_dport(uport)->mux;
692	int map_guard;
693	int ret;
694
695	map_guard = atomic_add_return(1, &mux->map_guard);
696	if (map_guard == 1) {
697		if (!request_mem_region(uport->mapbase, dec_kn_slot_size,
698					"dz")) {
699			atomic_add(-1, &mux->map_guard);
700			printk(KERN_ERR
701			       "dz: Unable to reserve MMIO resource\n");
702			return -EBUSY;
703		}
704	}
705	ret = dz_map_port(uport);
706	if (ret) {
707		map_guard = atomic_add_return(-1, &mux->map_guard);
708		if (!map_guard)
709			release_mem_region(uport->mapbase, dec_kn_slot_size);
710		return ret;
711	}
712	return 0;
713}
714
715static void dz_config_port(struct uart_port *uport, int flags)
716{
717	struct dz_port *dport = to_dport(uport);
718
719	if (flags & UART_CONFIG_TYPE) {
720		if (dz_request_port(uport))
721			return;
722
723		uport->type = PORT_DZ;
724
725		dz_reset(dport);
726	}
727}
728
729/*
730 * Verify the new serial_struct (for TIOCSSERIAL).
731 */
732static int dz_verify_port(struct uart_port *uport, struct serial_struct *ser)
733{
734	int ret = 0;
735
736	if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ)
737		ret = -EINVAL;
738	if (ser->irq != uport->irq)
739		ret = -EINVAL;
740	return ret;
741}
742
743static const struct uart_ops dz_ops = {
744	.tx_empty	= dz_tx_empty,
745	.get_mctrl	= dz_get_mctrl,
746	.set_mctrl	= dz_set_mctrl,
747	.stop_tx	= dz_stop_tx,
748	.start_tx	= dz_start_tx,
749	.stop_rx	= dz_stop_rx,
 
750	.break_ctl	= dz_break_ctl,
751	.startup	= dz_startup,
752	.shutdown	= dz_shutdown,
753	.set_termios	= dz_set_termios,
754	.pm		= dz_pm,
755	.type		= dz_type,
756	.release_port	= dz_release_port,
757	.request_port	= dz_request_port,
758	.config_port	= dz_config_port,
759	.verify_port	= dz_verify_port,
760};
761
762static void __init dz_init_ports(void)
763{
764	static int first = 1;
765	unsigned long base;
766	int line;
767
768	if (!first)
769		return;
770	first = 0;
771
772	if (mips_machtype == MACH_DS23100 || mips_machtype == MACH_DS5100)
773		base = dec_kn_slot_base + KN01_DZ11;
774	else
775		base = dec_kn_slot_base + KN02_DZ11;
776
777	for (line = 0; line < DZ_NB_PORT; line++) {
778		struct dz_port *dport = &dz_mux.dport[line];
779		struct uart_port *uport = &dport->port;
780
781		dport->mux	= &dz_mux;
782
783		uport->irq	= dec_interrupt[DEC_IRQ_DZ11];
784		uport->fifosize	= 1;
785		uport->iotype	= UPIO_MEM;
786		uport->flags	= UPF_BOOT_AUTOCONF;
787		uport->ops	= &dz_ops;
788		uport->line	= line;
789		uport->mapbase	= base;
790	}
791}
792
793#ifdef CONFIG_SERIAL_DZ_CONSOLE
794/*
795 * -------------------------------------------------------------------
796 * dz_console_putchar() -- transmit a character
797 *
798 * Polled transmission.  This is tricky.  We need to mask transmit
799 * interrupts so that they do not interfere, enable the transmitter
800 * for the line requested and then wait till the transmit scanner
801 * requests data for this line.  But it may request data for another
802 * line first, in which case we have to disable its transmitter and
803 * repeat waiting till our line pops up.  Only then the character may
804 * be transmitted.  Finally, the state of the transmitter mask is
805 * restored.  Welcome to the world of PDP-11!
806 * -------------------------------------------------------------------
807 */
808static void dz_console_putchar(struct uart_port *uport, int ch)
809{
810	struct dz_port *dport = to_dport(uport);
811	unsigned long flags;
812	unsigned short csr, tcr, trdy, mask;
813	int loops = 10000;
814
815	spin_lock_irqsave(&dport->port.lock, flags);
816	csr = dz_in(dport, DZ_CSR);
817	dz_out(dport, DZ_CSR, csr & ~DZ_TIE);
818	tcr = dz_in(dport, DZ_TCR);
819	tcr |= 1 << dport->port.line;
820	mask = tcr;
821	dz_out(dport, DZ_TCR, mask);
822	iob();
823	spin_unlock_irqrestore(&dport->port.lock, flags);
824
825	do {
826		trdy = dz_in(dport, DZ_CSR);
827		if (!(trdy & DZ_TRDY))
828			continue;
829		trdy = (trdy & DZ_TLINE) >> 8;
830		if (trdy == dport->port.line)
831			break;
832		mask &= ~(1 << trdy);
833		dz_out(dport, DZ_TCR, mask);
834		iob();
835		udelay(2);
836	} while (--loops);
837
838	if (loops)				/* Cannot send otherwise. */
839		dz_out(dport, DZ_TDR, ch);
840
841	dz_out(dport, DZ_TCR, tcr);
842	dz_out(dport, DZ_CSR, csr);
843}
844
845/*
846 * -------------------------------------------------------------------
847 * dz_console_print ()
848 *
849 * dz_console_print is registered for printk.
850 * The console must be locked when we get here.
851 * -------------------------------------------------------------------
852 */
853static void dz_console_print(struct console *co,
854			     const char *str,
855			     unsigned int count)
856{
857	struct dz_port *dport = &dz_mux.dport[co->index];
858#ifdef DEBUG_DZ
859	prom_printf((char *) str);
860#endif
861	uart_console_write(&dport->port, str, count, dz_console_putchar);
862}
863
864static int __init dz_console_setup(struct console *co, char *options)
865{
866	struct dz_port *dport = &dz_mux.dport[co->index];
867	struct uart_port *uport = &dport->port;
868	int baud = 9600;
869	int bits = 8;
870	int parity = 'n';
871	int flow = 'n';
872	int ret;
873
874	ret = dz_map_port(uport);
875	if (ret)
876		return ret;
877
878	spin_lock_init(&dport->port.lock);	/* For dz_pm().  */
879
880	dz_reset(dport);
881	dz_pm(uport, 0, -1);
882
883	if (options)
884		uart_parse_options(options, &baud, &parity, &bits, &flow);
885
886	return uart_set_options(&dport->port, co, baud, parity, bits, flow);
887}
888
889static struct uart_driver dz_reg;
890static struct console dz_console = {
891	.name	= "ttyS",
892	.write	= dz_console_print,
893	.device	= uart_console_device,
894	.setup	= dz_console_setup,
895	.flags	= CON_PRINTBUFFER,
896	.index	= -1,
897	.data	= &dz_reg,
898};
899
900static int __init dz_serial_console_init(void)
901{
902	if (!IOASIC) {
903		dz_init_ports();
904		register_console(&dz_console);
905		return 0;
906	} else
907		return -ENXIO;
908}
909
910console_initcall(dz_serial_console_init);
911
912#define SERIAL_DZ_CONSOLE	&dz_console
913#else
914#define SERIAL_DZ_CONSOLE	NULL
915#endif /* CONFIG_SERIAL_DZ_CONSOLE */
916
917static struct uart_driver dz_reg = {
918	.owner			= THIS_MODULE,
919	.driver_name		= "serial",
920	.dev_name		= "ttyS",
921	.major			= TTY_MAJOR,
922	.minor			= 64,
923	.nr			= DZ_NB_PORT,
924	.cons			= SERIAL_DZ_CONSOLE,
925};
926
927static int __init dz_init(void)
928{
929	int ret, i;
930
931	if (IOASIC)
932		return -ENXIO;
933
934	printk("%s%s\n", dz_name, dz_version);
935
936	dz_init_ports();
937
938	ret = uart_register_driver(&dz_reg);
939	if (ret)
940		return ret;
941
942	for (i = 0; i < DZ_NB_PORT; i++)
943		uart_add_one_port(&dz_reg, &dz_mux.dport[i].port);
944
945	return 0;
946}
947
948module_init(dz_init);
v3.15
 
  1/*
  2 * dz.c: Serial port driver for DECstations equipped
  3 *       with the DZ chipset.
  4 *
  5 * Copyright (C) 1998 Olivier A. D. Lebaillif
  6 *
  7 * Email: olivier.lebaillif@ifrsys.com
  8 *
  9 * Copyright (C) 2004, 2006, 2007  Maciej W. Rozycki
 10 *
 11 * [31-AUG-98] triemer
 12 * Changed IRQ to use Harald's dec internals interrupts.h
 13 * removed base_addr code - moving address assignment to setup.c
 14 * Changed name of dz_init to rs_init to be consistent with tc code
 15 * [13-NOV-98] triemer fixed code to receive characters
 16 *    after patches by harald to irq code.
 17 * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout
 18 *            field from "current" - somewhere between 2.1.121 and 2.1.131
 19 Qua Jun 27 15:02:26 BRT 2001
 20 * [27-JUN-2001] Arnaldo Carvalho de Melo <acme@conectiva.com.br> - cleanups
 21 *
 22 * Parts (C) 1999 David Airlie, airlied@linux.ie
 23 * [07-SEP-99] Bugfixes
 24 *
 25 * [06-Jan-2002] Russell King <rmk@arm.linux.org.uk>
 26 * Converted to new serial core
 27 */
 28
 29#undef DEBUG_DZ
 30
 31#if defined(CONFIG_SERIAL_DZ_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 32#define SUPPORT_SYSRQ
 33#endif
 34
 35#include <linux/bitops.h>
 36#include <linux/compiler.h>
 37#include <linux/console.h>
 38#include <linux/delay.h>
 39#include <linux/errno.h>
 40#include <linux/init.h>
 41#include <linux/interrupt.h>
 42#include <linux/ioport.h>
 43#include <linux/kernel.h>
 44#include <linux/major.h>
 45#include <linux/module.h>
 46#include <linux/serial.h>
 47#include <linux/serial_core.h>
 48#include <linux/sysrq.h>
 49#include <linux/tty.h>
 50#include <linux/tty_flip.h>
 51
 52#include <linux/atomic.h>
 53#include <asm/bootinfo.h>
 54#include <asm/io.h>
 55
 56#include <asm/dec/interrupts.h>
 57#include <asm/dec/kn01.h>
 58#include <asm/dec/kn02.h>
 59#include <asm/dec/machtype.h>
 60#include <asm/dec/prom.h>
 61#include <asm/dec/system.h>
 62
 63#include "dz.h"
 64
 65
 66MODULE_DESCRIPTION("DECstation DZ serial driver");
 67MODULE_LICENSE("GPL");
 68
 69
 70static char dz_name[] __initdata = "DECstation DZ serial driver version ";
 71static char dz_version[] __initdata = "1.04";
 72
 73struct dz_port {
 74	struct dz_mux		*mux;
 75	struct uart_port	port;
 76	unsigned int		cflag;
 77};
 78
 79struct dz_mux {
 80	struct dz_port		dport[DZ_NB_PORT];
 81	atomic_t		map_guard;
 82	atomic_t		irq_guard;
 83	int			initialised;
 84};
 85
 86static struct dz_mux dz_mux;
 87
 88static inline struct dz_port *to_dport(struct uart_port *uport)
 89{
 90	return container_of(uport, struct dz_port, port);
 91}
 92
 93/*
 94 * ------------------------------------------------------------
 95 * dz_in () and dz_out ()
 96 *
 97 * These routines are used to access the registers of the DZ
 98 * chip, hiding relocation differences between implementation.
 99 * ------------------------------------------------------------
100 */
101
102static u16 dz_in(struct dz_port *dport, unsigned offset)
103{
104	void __iomem *addr = dport->port.membase + offset;
105
106	return readw(addr);
107}
108
109static void dz_out(struct dz_port *dport, unsigned offset, u16 value)
110{
111	void __iomem *addr = dport->port.membase + offset;
112
113	writew(value, addr);
114}
115
116/*
117 * ------------------------------------------------------------
118 * rs_stop () and rs_start ()
119 *
120 * These routines are called before setting or resetting
121 * tty->stopped. They enable or disable transmitter interrupts,
122 * as necessary.
123 * ------------------------------------------------------------
124 */
125
126static void dz_stop_tx(struct uart_port *uport)
127{
128	struct dz_port *dport = to_dport(uport);
129	u16 tmp, mask = 1 << dport->port.line;
130
131	tmp = dz_in(dport, DZ_TCR);	/* read the TX flag */
132	tmp &= ~mask;			/* clear the TX flag */
133	dz_out(dport, DZ_TCR, tmp);
134}
135
136static void dz_start_tx(struct uart_port *uport)
137{
138	struct dz_port *dport = to_dport(uport);
139	u16 tmp, mask = 1 << dport->port.line;
140
141	tmp = dz_in(dport, DZ_TCR);	/* read the TX flag */
142	tmp |= mask;			/* set the TX flag */
143	dz_out(dport, DZ_TCR, tmp);
144}
145
146static void dz_stop_rx(struct uart_port *uport)
147{
148	struct dz_port *dport = to_dport(uport);
149
150	dport->cflag &= ~DZ_RXENAB;
151	dz_out(dport, DZ_LPR, dport->cflag);
152}
153
154static void dz_enable_ms(struct uart_port *uport)
155{
156	/* nothing to do */
157}
158
159/*
160 * ------------------------------------------------------------
161 *
162 * Here start the interrupt handling routines.  All of the following
163 * subroutines are declared as inline and are folded into
164 * dz_interrupt.  They were separated out for readability's sake.
165 *
166 * Note: dz_interrupt() is a "fast" interrupt, which means that it
167 * runs with interrupts turned off.  People who may want to modify
168 * dz_interrupt() should try to keep the interrupt handler as fast as
169 * possible.  After you are done making modifications, it is not a bad
170 * idea to do:
171 *
172 *	make drivers/serial/dz.s
173 *
174 * and look at the resulting assemble code in dz.s.
175 *
176 * ------------------------------------------------------------
177 */
178
179/*
180 * ------------------------------------------------------------
181 * receive_char ()
182 *
183 * This routine deals with inputs from any lines.
184 * ------------------------------------------------------------
185 */
186static inline void dz_receive_chars(struct dz_mux *mux)
187{
188	struct uart_port *uport;
189	struct dz_port *dport = &mux->dport[0];
190	struct uart_icount *icount;
191	int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
192	unsigned char ch, flag;
193	u16 status;
194	int i;
195
196	while ((status = dz_in(dport, DZ_RBUF)) & DZ_DVAL) {
197		dport = &mux->dport[LINE(status)];
198		uport = &dport->port;
199
200		ch = UCHAR(status);		/* grab the char */
201		flag = TTY_NORMAL;
202
203		icount = &uport->icount;
204		icount->rx++;
205
206		if (unlikely(status & (DZ_OERR | DZ_FERR | DZ_PERR))) {
207
208			/*
209			 * There is no separate BREAK status bit, so treat
210			 * null characters with framing errors as BREAKs;
211			 * normally, otherwise.  For this move the Framing
212			 * Error bit to a simulated BREAK bit.
213			 */
214			if (!ch) {
215				status |= (status & DZ_FERR) >>
216					  (ffs(DZ_FERR) - ffs(DZ_BREAK));
217				status &= ~DZ_FERR;
218			}
219
220			/* Handle SysRq/SAK & keep track of the statistics. */
221			if (status & DZ_BREAK) {
222				icount->brk++;
223				if (uart_handle_break(uport))
224					continue;
225			} else if (status & DZ_FERR)
226				icount->frame++;
227			else if (status & DZ_PERR)
228				icount->parity++;
229			if (status & DZ_OERR)
230				icount->overrun++;
231
232			status &= uport->read_status_mask;
233			if (status & DZ_BREAK)
234				flag = TTY_BREAK;
235			else if (status & DZ_FERR)
236				flag = TTY_FRAME;
237			else if (status & DZ_PERR)
238				flag = TTY_PARITY;
239
240		}
241
242		if (uart_handle_sysrq_char(uport, ch))
243			continue;
244
245		uart_insert_char(uport, status, DZ_OERR, ch, flag);
246		lines_rx[LINE(status)] = 1;
247	}
248	for (i = 0; i < DZ_NB_PORT; i++)
249		if (lines_rx[i])
250			tty_flip_buffer_push(&mux->dport[i].port.state->port);
251}
252
253/*
254 * ------------------------------------------------------------
255 * transmit_char ()
256 *
257 * This routine deals with outputs to any lines.
258 * ------------------------------------------------------------
259 */
260static inline void dz_transmit_chars(struct dz_mux *mux)
261{
262	struct dz_port *dport = &mux->dport[0];
263	struct circ_buf *xmit;
264	unsigned char tmp;
265	u16 status;
266
267	status = dz_in(dport, DZ_CSR);
268	dport = &mux->dport[LINE(status)];
269	xmit = &dport->port.state->xmit;
270
271	if (dport->port.x_char) {		/* XON/XOFF chars */
272		dz_out(dport, DZ_TDR, dport->port.x_char);
273		dport->port.icount.tx++;
274		dport->port.x_char = 0;
275		return;
276	}
277	/* If nothing to do or stopped or hardware stopped. */
278	if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) {
279		spin_lock(&dport->port.lock);
280		dz_stop_tx(&dport->port);
281		spin_unlock(&dport->port.lock);
282		return;
283	}
284
285	/*
286	 * If something to do... (remember the dz has no output fifo,
287	 * so we go one char at a time) :-<
288	 */
289	tmp = xmit->buf[xmit->tail];
290	xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
291	dz_out(dport, DZ_TDR, tmp);
292	dport->port.icount.tx++;
293
294	if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS)
295		uart_write_wakeup(&dport->port);
296
297	/* Are we are done. */
298	if (uart_circ_empty(xmit)) {
299		spin_lock(&dport->port.lock);
300		dz_stop_tx(&dport->port);
301		spin_unlock(&dport->port.lock);
302	}
303}
304
305/*
306 * ------------------------------------------------------------
307 * check_modem_status()
308 *
309 * DS 3100 & 5100: Only valid for the MODEM line, duh!
310 * DS 5000/200: Valid for the MODEM and PRINTER line.
311 * ------------------------------------------------------------
312 */
313static inline void check_modem_status(struct dz_port *dport)
314{
315	/*
316	 * FIXME:
317	 * 1. No status change interrupt; use a timer.
318	 * 2. Handle the 3100/5000 as appropriate. --macro
319	 */
320	u16 status;
321
322	/* If not the modem line just return.  */
323	if (dport->port.line != DZ_MODEM)
324		return;
325
326	status = dz_in(dport, DZ_MSR);
327
328	/* it's easy, since DSR2 is the only bit in the register */
329	if (status)
330		dport->port.icount.dsr++;
331}
332
333/*
334 * ------------------------------------------------------------
335 * dz_interrupt ()
336 *
337 * this is the main interrupt routine for the DZ chip.
338 * It deals with the multiple ports.
339 * ------------------------------------------------------------
340 */
341static irqreturn_t dz_interrupt(int irq, void *dev_id)
342{
343	struct dz_mux *mux = dev_id;
344	struct dz_port *dport = &mux->dport[0];
345	u16 status;
346
347	/* get the reason why we just got an irq */
348	status = dz_in(dport, DZ_CSR);
349
350	if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE))
351		dz_receive_chars(mux);
352
353	if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE))
354		dz_transmit_chars(mux);
355
356	return IRQ_HANDLED;
357}
358
359/*
360 * -------------------------------------------------------------------
361 * Here ends the DZ interrupt routines.
362 * -------------------------------------------------------------------
363 */
364
365static unsigned int dz_get_mctrl(struct uart_port *uport)
366{
367	/*
368	 * FIXME: Handle the 3100/5000 as appropriate. --macro
369	 */
370	struct dz_port *dport = to_dport(uport);
371	unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
372
373	if (dport->port.line == DZ_MODEM) {
374		if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR)
375			mctrl &= ~TIOCM_DSR;
376	}
377
378	return mctrl;
379}
380
381static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
382{
383	/*
384	 * FIXME: Handle the 3100/5000 as appropriate. --macro
385	 */
386	struct dz_port *dport = to_dport(uport);
387	u16 tmp;
388
389	if (dport->port.line == DZ_MODEM) {
390		tmp = dz_in(dport, DZ_TCR);
391		if (mctrl & TIOCM_DTR)
392			tmp &= ~DZ_MODEM_DTR;
393		else
394			tmp |= DZ_MODEM_DTR;
395		dz_out(dport, DZ_TCR, tmp);
396	}
397}
398
399/*
400 * -------------------------------------------------------------------
401 * startup ()
402 *
403 * various initialization tasks
404 * -------------------------------------------------------------------
405 */
406static int dz_startup(struct uart_port *uport)
407{
408	struct dz_port *dport = to_dport(uport);
409	struct dz_mux *mux = dport->mux;
410	unsigned long flags;
411	int irq_guard;
412	int ret;
413	u16 tmp;
414
415	irq_guard = atomic_add_return(1, &mux->irq_guard);
416	if (irq_guard != 1)
417		return 0;
418
419	ret = request_irq(dport->port.irq, dz_interrupt,
420			  IRQF_SHARED, "dz", mux);
421	if (ret) {
422		atomic_add(-1, &mux->irq_guard);
423		printk(KERN_ERR "dz: Cannot get IRQ %d!\n", dport->port.irq);
424		return ret;
425	}
426
427	spin_lock_irqsave(&dport->port.lock, flags);
428
429	/* Enable interrupts.  */
430	tmp = dz_in(dport, DZ_CSR);
431	tmp |= DZ_RIE | DZ_TIE;
432	dz_out(dport, DZ_CSR, tmp);
433
434	spin_unlock_irqrestore(&dport->port.lock, flags);
435
436	return 0;
437}
438
439/*
440 * -------------------------------------------------------------------
441 * shutdown ()
442 *
443 * This routine will shutdown a serial port; interrupts are disabled, and
444 * DTR is dropped if the hangup on close termio flag is on.
445 * -------------------------------------------------------------------
446 */
447static void dz_shutdown(struct uart_port *uport)
448{
449	struct dz_port *dport = to_dport(uport);
450	struct dz_mux *mux = dport->mux;
451	unsigned long flags;
452	int irq_guard;
453	u16 tmp;
454
455	spin_lock_irqsave(&dport->port.lock, flags);
456	dz_stop_tx(&dport->port);
457	spin_unlock_irqrestore(&dport->port.lock, flags);
458
459	irq_guard = atomic_add_return(-1, &mux->irq_guard);
460	if (!irq_guard) {
461		/* Disable interrupts.  */
462		tmp = dz_in(dport, DZ_CSR);
463		tmp &= ~(DZ_RIE | DZ_TIE);
464		dz_out(dport, DZ_CSR, tmp);
465
466		free_irq(dport->port.irq, mux);
467	}
468}
469
470/*
471 * -------------------------------------------------------------------
472 * dz_tx_empty() -- get the transmitter empty status
473 *
474 * Purpose: Let user call ioctl() to get info when the UART physically
475 *          is emptied.  On bus types like RS485, the transmitter must
476 *          release the bus after transmitting. This must be done when
477 *          the transmit shift register is empty, not be done when the
478 *          transmit holding register is empty.  This functionality
479 *          allows an RS485 driver to be written in user space.
480 * -------------------------------------------------------------------
481 */
482static unsigned int dz_tx_empty(struct uart_port *uport)
483{
484	struct dz_port *dport = to_dport(uport);
485	unsigned short tmp, mask = 1 << dport->port.line;
486
487	tmp = dz_in(dport, DZ_TCR);
488	tmp &= mask;
489
490	return tmp ? 0 : TIOCSER_TEMT;
491}
492
493static void dz_break_ctl(struct uart_port *uport, int break_state)
494{
495	/*
496	 * FIXME: Can't access BREAK bits in TDR easily;
497	 * reuse the code for polled TX. --macro
498	 */
499	struct dz_port *dport = to_dport(uport);
500	unsigned long flags;
501	unsigned short tmp, mask = 1 << dport->port.line;
502
503	spin_lock_irqsave(&uport->lock, flags);
504	tmp = dz_in(dport, DZ_TCR);
505	if (break_state)
506		tmp |= mask;
507	else
508		tmp &= ~mask;
509	dz_out(dport, DZ_TCR, tmp);
510	spin_unlock_irqrestore(&uport->lock, flags);
511}
512
513static int dz_encode_baud_rate(unsigned int baud)
514{
515	switch (baud) {
516	case 50:
517		return DZ_B50;
518	case 75:
519		return DZ_B75;
520	case 110:
521		return DZ_B110;
522	case 134:
523		return DZ_B134;
524	case 150:
525		return DZ_B150;
526	case 300:
527		return DZ_B300;
528	case 600:
529		return DZ_B600;
530	case 1200:
531		return DZ_B1200;
532	case 1800:
533		return DZ_B1800;
534	case 2000:
535		return DZ_B2000;
536	case 2400:
537		return DZ_B2400;
538	case 3600:
539		return DZ_B3600;
540	case 4800:
541		return DZ_B4800;
542	case 7200:
543		return DZ_B7200;
544	case 9600:
545		return DZ_B9600;
546	default:
547		return -1;
548	}
549}
550
551
552static void dz_reset(struct dz_port *dport)
553{
554	struct dz_mux *mux = dport->mux;
555
556	if (mux->initialised)
557		return;
558
559	dz_out(dport, DZ_CSR, DZ_CLR);
560	while (dz_in(dport, DZ_CSR) & DZ_CLR);
561	iob();
562
563	/* Enable scanning.  */
564	dz_out(dport, DZ_CSR, DZ_MSE);
565
566	mux->initialised = 1;
567}
568
569static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
570			   struct ktermios *old_termios)
571{
572	struct dz_port *dport = to_dport(uport);
573	unsigned long flags;
574	unsigned int cflag, baud;
575	int bflag;
576
577	cflag = dport->port.line;
578
579	switch (termios->c_cflag & CSIZE) {
580	case CS5:
581		cflag |= DZ_CS5;
582		break;
583	case CS6:
584		cflag |= DZ_CS6;
585		break;
586	case CS7:
587		cflag |= DZ_CS7;
588		break;
589	case CS8:
590	default:
591		cflag |= DZ_CS8;
592	}
593
594	if (termios->c_cflag & CSTOPB)
595		cflag |= DZ_CSTOPB;
596	if (termios->c_cflag & PARENB)
597		cflag |= DZ_PARENB;
598	if (termios->c_cflag & PARODD)
599		cflag |= DZ_PARODD;
600
601	baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600);
602	bflag = dz_encode_baud_rate(baud);
603	if (bflag < 0)	{			/* Try to keep unchanged.  */
604		baud = uart_get_baud_rate(uport, old_termios, NULL, 50, 9600);
605		bflag = dz_encode_baud_rate(baud);
606		if (bflag < 0)	{		/* Resort to 9600.  */
607			baud = 9600;
608			bflag = DZ_B9600;
609		}
610		tty_termios_encode_baud_rate(termios, baud, baud);
611	}
612	cflag |= bflag;
613
614	if (termios->c_cflag & CREAD)
615		cflag |= DZ_RXENAB;
616
617	spin_lock_irqsave(&dport->port.lock, flags);
618
619	uart_update_timeout(uport, termios->c_cflag, baud);
620
621	dz_out(dport, DZ_LPR, cflag);
622	dport->cflag = cflag;
623
624	/* setup accept flag */
625	dport->port.read_status_mask = DZ_OERR;
626	if (termios->c_iflag & INPCK)
627		dport->port.read_status_mask |= DZ_FERR | DZ_PERR;
628	if (termios->c_iflag & (BRKINT | PARMRK))
629		dport->port.read_status_mask |= DZ_BREAK;
630
631	/* characters to ignore */
632	uport->ignore_status_mask = 0;
633	if ((termios->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
634		dport->port.ignore_status_mask |= DZ_OERR;
635	if (termios->c_iflag & IGNPAR)
636		dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR;
637	if (termios->c_iflag & IGNBRK)
638		dport->port.ignore_status_mask |= DZ_BREAK;
639
640	spin_unlock_irqrestore(&dport->port.lock, flags);
641}
642
643/*
644 * Hack alert!
645 * Required solely so that the initial PROM-based console
646 * works undisturbed in parallel with this one.
647 */
648static void dz_pm(struct uart_port *uport, unsigned int state,
649		  unsigned int oldstate)
650{
651	struct dz_port *dport = to_dport(uport);
652	unsigned long flags;
653
654	spin_lock_irqsave(&dport->port.lock, flags);
655	if (state < 3)
656		dz_start_tx(&dport->port);
657	else
658		dz_stop_tx(&dport->port);
659	spin_unlock_irqrestore(&dport->port.lock, flags);
660}
661
662
663static const char *dz_type(struct uart_port *uport)
664{
665	return "DZ";
666}
667
668static void dz_release_port(struct uart_port *uport)
669{
670	struct dz_mux *mux = to_dport(uport)->mux;
671	int map_guard;
672
673	iounmap(uport->membase);
674	uport->membase = NULL;
675
676	map_guard = atomic_add_return(-1, &mux->map_guard);
677	if (!map_guard)
678		release_mem_region(uport->mapbase, dec_kn_slot_size);
679}
680
681static int dz_map_port(struct uart_port *uport)
682{
683	if (!uport->membase)
684		uport->membase = ioremap_nocache(uport->mapbase,
685						 dec_kn_slot_size);
686	if (!uport->membase) {
687		printk(KERN_ERR "dz: Cannot map MMIO\n");
688		return -ENOMEM;
689	}
690	return 0;
691}
692
693static int dz_request_port(struct uart_port *uport)
694{
695	struct dz_mux *mux = to_dport(uport)->mux;
696	int map_guard;
697	int ret;
698
699	map_guard = atomic_add_return(1, &mux->map_guard);
700	if (map_guard == 1) {
701		if (!request_mem_region(uport->mapbase, dec_kn_slot_size,
702					"dz")) {
703			atomic_add(-1, &mux->map_guard);
704			printk(KERN_ERR
705			       "dz: Unable to reserve MMIO resource\n");
706			return -EBUSY;
707		}
708	}
709	ret = dz_map_port(uport);
710	if (ret) {
711		map_guard = atomic_add_return(-1, &mux->map_guard);
712		if (!map_guard)
713			release_mem_region(uport->mapbase, dec_kn_slot_size);
714		return ret;
715	}
716	return 0;
717}
718
719static void dz_config_port(struct uart_port *uport, int flags)
720{
721	struct dz_port *dport = to_dport(uport);
722
723	if (flags & UART_CONFIG_TYPE) {
724		if (dz_request_port(uport))
725			return;
726
727		uport->type = PORT_DZ;
728
729		dz_reset(dport);
730	}
731}
732
733/*
734 * Verify the new serial_struct (for TIOCSSERIAL).
735 */
736static int dz_verify_port(struct uart_port *uport, struct serial_struct *ser)
737{
738	int ret = 0;
739
740	if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ)
741		ret = -EINVAL;
742	if (ser->irq != uport->irq)
743		ret = -EINVAL;
744	return ret;
745}
746
747static struct uart_ops dz_ops = {
748	.tx_empty	= dz_tx_empty,
749	.get_mctrl	= dz_get_mctrl,
750	.set_mctrl	= dz_set_mctrl,
751	.stop_tx	= dz_stop_tx,
752	.start_tx	= dz_start_tx,
753	.stop_rx	= dz_stop_rx,
754	.enable_ms	= dz_enable_ms,
755	.break_ctl	= dz_break_ctl,
756	.startup	= dz_startup,
757	.shutdown	= dz_shutdown,
758	.set_termios	= dz_set_termios,
759	.pm		= dz_pm,
760	.type		= dz_type,
761	.release_port	= dz_release_port,
762	.request_port	= dz_request_port,
763	.config_port	= dz_config_port,
764	.verify_port	= dz_verify_port,
765};
766
767static void __init dz_init_ports(void)
768{
769	static int first = 1;
770	unsigned long base;
771	int line;
772
773	if (!first)
774		return;
775	first = 0;
776
777	if (mips_machtype == MACH_DS23100 || mips_machtype == MACH_DS5100)
778		base = dec_kn_slot_base + KN01_DZ11;
779	else
780		base = dec_kn_slot_base + KN02_DZ11;
781
782	for (line = 0; line < DZ_NB_PORT; line++) {
783		struct dz_port *dport = &dz_mux.dport[line];
784		struct uart_port *uport = &dport->port;
785
786		dport->mux	= &dz_mux;
787
788		uport->irq	= dec_interrupt[DEC_IRQ_DZ11];
789		uport->fifosize	= 1;
790		uport->iotype	= UPIO_MEM;
791		uport->flags	= UPF_BOOT_AUTOCONF;
792		uport->ops	= &dz_ops;
793		uport->line	= line;
794		uport->mapbase	= base;
795	}
796}
797
798#ifdef CONFIG_SERIAL_DZ_CONSOLE
799/*
800 * -------------------------------------------------------------------
801 * dz_console_putchar() -- transmit a character
802 *
803 * Polled transmission.  This is tricky.  We need to mask transmit
804 * interrupts so that they do not interfere, enable the transmitter
805 * for the line requested and then wait till the transmit scanner
806 * requests data for this line.  But it may request data for another
807 * line first, in which case we have to disable its transmitter and
808 * repeat waiting till our line pops up.  Only then the character may
809 * be transmitted.  Finally, the state of the transmitter mask is
810 * restored.  Welcome to the world of PDP-11!
811 * -------------------------------------------------------------------
812 */
813static void dz_console_putchar(struct uart_port *uport, int ch)
814{
815	struct dz_port *dport = to_dport(uport);
816	unsigned long flags;
817	unsigned short csr, tcr, trdy, mask;
818	int loops = 10000;
819
820	spin_lock_irqsave(&dport->port.lock, flags);
821	csr = dz_in(dport, DZ_CSR);
822	dz_out(dport, DZ_CSR, csr & ~DZ_TIE);
823	tcr = dz_in(dport, DZ_TCR);
824	tcr |= 1 << dport->port.line;
825	mask = tcr;
826	dz_out(dport, DZ_TCR, mask);
827	iob();
828	spin_unlock_irqrestore(&dport->port.lock, flags);
829
830	do {
831		trdy = dz_in(dport, DZ_CSR);
832		if (!(trdy & DZ_TRDY))
833			continue;
834		trdy = (trdy & DZ_TLINE) >> 8;
835		if (trdy == dport->port.line)
836			break;
837		mask &= ~(1 << trdy);
838		dz_out(dport, DZ_TCR, mask);
839		iob();
840		udelay(2);
841	} while (--loops);
842
843	if (loops)				/* Cannot send otherwise. */
844		dz_out(dport, DZ_TDR, ch);
845
846	dz_out(dport, DZ_TCR, tcr);
847	dz_out(dport, DZ_CSR, csr);
848}
849
850/*
851 * -------------------------------------------------------------------
852 * dz_console_print ()
853 *
854 * dz_console_print is registered for printk.
855 * The console must be locked when we get here.
856 * -------------------------------------------------------------------
857 */
858static void dz_console_print(struct console *co,
859			     const char *str,
860			     unsigned int count)
861{
862	struct dz_port *dport = &dz_mux.dport[co->index];
863#ifdef DEBUG_DZ
864	prom_printf((char *) str);
865#endif
866	uart_console_write(&dport->port, str, count, dz_console_putchar);
867}
868
869static int __init dz_console_setup(struct console *co, char *options)
870{
871	struct dz_port *dport = &dz_mux.dport[co->index];
872	struct uart_port *uport = &dport->port;
873	int baud = 9600;
874	int bits = 8;
875	int parity = 'n';
876	int flow = 'n';
877	int ret;
878
879	ret = dz_map_port(uport);
880	if (ret)
881		return ret;
882
883	spin_lock_init(&dport->port.lock);	/* For dz_pm().  */
884
885	dz_reset(dport);
886	dz_pm(uport, 0, -1);
887
888	if (options)
889		uart_parse_options(options, &baud, &parity, &bits, &flow);
890
891	return uart_set_options(&dport->port, co, baud, parity, bits, flow);
892}
893
894static struct uart_driver dz_reg;
895static struct console dz_console = {
896	.name	= "ttyS",
897	.write	= dz_console_print,
898	.device	= uart_console_device,
899	.setup	= dz_console_setup,
900	.flags	= CON_PRINTBUFFER,
901	.index	= -1,
902	.data	= &dz_reg,
903};
904
905static int __init dz_serial_console_init(void)
906{
907	if (!IOASIC) {
908		dz_init_ports();
909		register_console(&dz_console);
910		return 0;
911	} else
912		return -ENXIO;
913}
914
915console_initcall(dz_serial_console_init);
916
917#define SERIAL_DZ_CONSOLE	&dz_console
918#else
919#define SERIAL_DZ_CONSOLE	NULL
920#endif /* CONFIG_SERIAL_DZ_CONSOLE */
921
922static struct uart_driver dz_reg = {
923	.owner			= THIS_MODULE,
924	.driver_name		= "serial",
925	.dev_name		= "ttyS",
926	.major			= TTY_MAJOR,
927	.minor			= 64,
928	.nr			= DZ_NB_PORT,
929	.cons			= SERIAL_DZ_CONSOLE,
930};
931
932static int __init dz_init(void)
933{
934	int ret, i;
935
936	if (IOASIC)
937		return -ENXIO;
938
939	printk("%s%s\n", dz_name, dz_version);
940
941	dz_init_ports();
942
943	ret = uart_register_driver(&dz_reg);
944	if (ret)
945		return ret;
946
947	for (i = 0; i < DZ_NB_PORT; i++)
948		uart_add_one_port(&dz_reg, &dz_mux.dport[i].port);
949
950	return 0;
951}
952
953module_init(dz_init);