/drivers/tty/serial/pmac_zilog.c
C | 2206 lines | 1466 code | 339 blank | 401 comment | 290 complexity | 1f1725625c5ed44c9818af04bf0ba409 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
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1/*
2 * Driver for PowerMac Z85c30 based ESCC cell found in the
3 * "macio" ASICs of various PowerMac models
4 *
5 * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
6 *
7 * Derived from drivers/macintosh/macserial.c by Paul Mackerras
8 * and drivers/serial/sunzilog.c by David S. Miller
9 *
10 * Hrm... actually, I ripped most of sunzilog (Thanks David !) and
11 * adapted special tweaks needed for us. I don't think it's worth
12 * merging back those though. The DMA code still has to get in
13 * and once done, I expect that driver to remain fairly stable in
14 * the long term, unless we change the driver model again...
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 *
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License
27 * along with this program; if not, write to the Free Software
28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
29 *
30 * 2004-08-06 Harald Welte <laforge@gnumonks.org>
31 * - Enable BREAK interrupt
32 * - Add support for sysreq
33 *
34 * TODO: - Add DMA support
35 * - Defer port shutdown to a few seconds after close
36 * - maybe put something right into uap->clk_divisor
37 */
38
39#undef DEBUG
40#undef DEBUG_HARD
41#undef USE_CTRL_O_SYSRQ
42
43#include <linux/module.h>
44#include <linux/tty.h>
45
46#include <linux/tty_flip.h>
47#include <linux/major.h>
48#include <linux/string.h>
49#include <linux/fcntl.h>
50#include <linux/mm.h>
51#include <linux/kernel.h>
52#include <linux/delay.h>
53#include <linux/init.h>
54#include <linux/console.h>
55#include <linux/adb.h>
56#include <linux/pmu.h>
57#include <linux/bitops.h>
58#include <linux/sysrq.h>
59#include <linux/mutex.h>
60#include <asm/sections.h>
61#include <asm/io.h>
62#include <asm/irq.h>
63
64#ifdef CONFIG_PPC_PMAC
65#include <asm/prom.h>
66#include <asm/machdep.h>
67#include <asm/pmac_feature.h>
68#include <asm/dbdma.h>
69#include <asm/macio.h>
70#else
71#include <linux/platform_device.h>
72#define of_machine_is_compatible(x) (0)
73#endif
74
75#if defined (CONFIG_SERIAL_PMACZILOG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
76#define SUPPORT_SYSRQ
77#endif
78
79#include <linux/serial.h>
80#include <linux/serial_core.h>
81
82#include "pmac_zilog.h"
83
84/* Not yet implemented */
85#undef HAS_DBDMA
86
87static char version[] __initdata = "pmac_zilog: 0.6 (Benjamin Herrenschmidt <benh@kernel.crashing.org>)";
88MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
89MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
90MODULE_LICENSE("GPL");
91
92#ifdef CONFIG_SERIAL_PMACZILOG_TTYS
93#define PMACZILOG_MAJOR TTY_MAJOR
94#define PMACZILOG_MINOR 64
95#define PMACZILOG_NAME "ttyS"
96#else
97#define PMACZILOG_MAJOR 204
98#define PMACZILOG_MINOR 192
99#define PMACZILOG_NAME "ttyPZ"
100#endif
101
102
103/*
104 * For the sake of early serial console, we can do a pre-probe
105 * (optional) of the ports at rather early boot time.
106 */
107static struct uart_pmac_port pmz_ports[MAX_ZS_PORTS];
108static int pmz_ports_count;
109static DEFINE_MUTEX(pmz_irq_mutex);
110
111static struct uart_driver pmz_uart_reg = {
112 .owner = THIS_MODULE,
113 .driver_name = PMACZILOG_NAME,
114 .dev_name = PMACZILOG_NAME,
115 .major = PMACZILOG_MAJOR,
116 .minor = PMACZILOG_MINOR,
117};
118
119
120/*
121 * Load all registers to reprogram the port
122 * This function must only be called when the TX is not busy. The UART
123 * port lock must be held and local interrupts disabled.
124 */
125static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
126{
127 int i;
128
129 if (ZS_IS_ASLEEP(uap))
130 return;
131
132 /* Let pending transmits finish. */
133 for (i = 0; i < 1000; i++) {
134 unsigned char stat = read_zsreg(uap, R1);
135 if (stat & ALL_SNT)
136 break;
137 udelay(100);
138 }
139
140 ZS_CLEARERR(uap);
141 zssync(uap);
142 ZS_CLEARFIFO(uap);
143 zssync(uap);
144 ZS_CLEARERR(uap);
145
146 /* Disable all interrupts. */
147 write_zsreg(uap, R1,
148 regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
149
150 /* Set parity, sync config, stop bits, and clock divisor. */
151 write_zsreg(uap, R4, regs[R4]);
152
153 /* Set misc. TX/RX control bits. */
154 write_zsreg(uap, R10, regs[R10]);
155
156 /* Set TX/RX controls sans the enable bits. */
157 write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
158 write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
159
160 /* now set R7 "prime" on ESCC */
161 write_zsreg(uap, R15, regs[R15] | EN85C30);
162 write_zsreg(uap, R7, regs[R7P]);
163
164 /* make sure we use R7 "non-prime" on ESCC */
165 write_zsreg(uap, R15, regs[R15] & ~EN85C30);
166
167 /* Synchronous mode config. */
168 write_zsreg(uap, R6, regs[R6]);
169 write_zsreg(uap, R7, regs[R7]);
170
171 /* Disable baud generator. */
172 write_zsreg(uap, R14, regs[R14] & ~BRENAB);
173
174 /* Clock mode control. */
175 write_zsreg(uap, R11, regs[R11]);
176
177 /* Lower and upper byte of baud rate generator divisor. */
178 write_zsreg(uap, R12, regs[R12]);
179 write_zsreg(uap, R13, regs[R13]);
180
181 /* Now rewrite R14, with BRENAB (if set). */
182 write_zsreg(uap, R14, regs[R14]);
183
184 /* Reset external status interrupts. */
185 write_zsreg(uap, R0, RES_EXT_INT);
186 write_zsreg(uap, R0, RES_EXT_INT);
187
188 /* Rewrite R3/R5, this time without enables masked. */
189 write_zsreg(uap, R3, regs[R3]);
190 write_zsreg(uap, R5, regs[R5]);
191
192 /* Rewrite R1, this time without IRQ enabled masked. */
193 write_zsreg(uap, R1, regs[R1]);
194
195 /* Enable interrupts */
196 write_zsreg(uap, R9, regs[R9]);
197}
198
199/*
200 * We do like sunzilog to avoid disrupting pending Tx
201 * Reprogram the Zilog channel HW registers with the copies found in the
202 * software state struct. If the transmitter is busy, we defer this update
203 * until the next TX complete interrupt. Else, we do it right now.
204 *
205 * The UART port lock must be held and local interrupts disabled.
206 */
207static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
208{
209 if (!ZS_REGS_HELD(uap)) {
210 if (ZS_TX_ACTIVE(uap)) {
211 uap->flags |= PMACZILOG_FLAG_REGS_HELD;
212 } else {
213 pmz_debug("pmz: maybe_update_regs: updating\n");
214 pmz_load_zsregs(uap, uap->curregs);
215 }
216 }
217}
218
219static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
220{
221 struct tty_struct *tty = NULL;
222 unsigned char ch, r1, drop, error, flag;
223 int loops = 0;
224
225 /* The interrupt can be enabled when the port isn't open, typically
226 * that happens when using one port is open and the other closed (stale
227 * interrupt) or when one port is used as a console.
228 */
229 if (!ZS_IS_OPEN(uap)) {
230 pmz_debug("pmz: draining input\n");
231 /* Port is closed, drain input data */
232 for (;;) {
233 if ((++loops) > 1000)
234 goto flood;
235 (void)read_zsreg(uap, R1);
236 write_zsreg(uap, R0, ERR_RES);
237 (void)read_zsdata(uap);
238 ch = read_zsreg(uap, R0);
239 if (!(ch & Rx_CH_AV))
240 break;
241 }
242 return NULL;
243 }
244
245 /* Sanity check, make sure the old bug is no longer happening */
246 if (uap->port.state == NULL || uap->port.state->port.tty == NULL) {
247 WARN_ON(1);
248 (void)read_zsdata(uap);
249 return NULL;
250 }
251 tty = uap->port.state->port.tty;
252
253 while (1) {
254 error = 0;
255 drop = 0;
256
257 r1 = read_zsreg(uap, R1);
258 ch = read_zsdata(uap);
259
260 if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
261 write_zsreg(uap, R0, ERR_RES);
262 zssync(uap);
263 }
264
265 ch &= uap->parity_mask;
266 if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
267 uap->flags &= ~PMACZILOG_FLAG_BREAK;
268 }
269
270#if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
271#ifdef USE_CTRL_O_SYSRQ
272 /* Handle the SysRq ^O Hack */
273 if (ch == '\x0f') {
274 uap->port.sysrq = jiffies + HZ*5;
275 goto next_char;
276 }
277#endif /* USE_CTRL_O_SYSRQ */
278 if (uap->port.sysrq) {
279 int swallow;
280 spin_unlock(&uap->port.lock);
281 swallow = uart_handle_sysrq_char(&uap->port, ch);
282 spin_lock(&uap->port.lock);
283 if (swallow)
284 goto next_char;
285 }
286#endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
287
288 /* A real serial line, record the character and status. */
289 if (drop)
290 goto next_char;
291
292 flag = TTY_NORMAL;
293 uap->port.icount.rx++;
294
295 if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
296 error = 1;
297 if (r1 & BRK_ABRT) {
298 pmz_debug("pmz: got break !\n");
299 r1 &= ~(PAR_ERR | CRC_ERR);
300 uap->port.icount.brk++;
301 if (uart_handle_break(&uap->port))
302 goto next_char;
303 }
304 else if (r1 & PAR_ERR)
305 uap->port.icount.parity++;
306 else if (r1 & CRC_ERR)
307 uap->port.icount.frame++;
308 if (r1 & Rx_OVR)
309 uap->port.icount.overrun++;
310 r1 &= uap->port.read_status_mask;
311 if (r1 & BRK_ABRT)
312 flag = TTY_BREAK;
313 else if (r1 & PAR_ERR)
314 flag = TTY_PARITY;
315 else if (r1 & CRC_ERR)
316 flag = TTY_FRAME;
317 }
318
319 if (uap->port.ignore_status_mask == 0xff ||
320 (r1 & uap->port.ignore_status_mask) == 0) {
321 tty_insert_flip_char(tty, ch, flag);
322 }
323 if (r1 & Rx_OVR)
324 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
325 next_char:
326 /* We can get stuck in an infinite loop getting char 0 when the
327 * line is in a wrong HW state, we break that here.
328 * When that happens, I disable the receive side of the driver.
329 * Note that what I've been experiencing is a real irq loop where
330 * I'm getting flooded regardless of the actual port speed.
331 * Something strange is going on with the HW
332 */
333 if ((++loops) > 1000)
334 goto flood;
335 ch = read_zsreg(uap, R0);
336 if (!(ch & Rx_CH_AV))
337 break;
338 }
339
340 return tty;
341 flood:
342 uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
343 write_zsreg(uap, R1, uap->curregs[R1]);
344 zssync(uap);
345 pmz_error("pmz: rx irq flood !\n");
346 return tty;
347}
348
349static void pmz_status_handle(struct uart_pmac_port *uap)
350{
351 unsigned char status;
352
353 status = read_zsreg(uap, R0);
354 write_zsreg(uap, R0, RES_EXT_INT);
355 zssync(uap);
356
357 if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
358 if (status & SYNC_HUNT)
359 uap->port.icount.dsr++;
360
361 /* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
362 * But it does not tell us which bit has changed, we have to keep
363 * track of this ourselves.
364 * The CTS input is inverted for some reason. -- paulus
365 */
366 if ((status ^ uap->prev_status) & DCD)
367 uart_handle_dcd_change(&uap->port,
368 (status & DCD));
369 if ((status ^ uap->prev_status) & CTS)
370 uart_handle_cts_change(&uap->port,
371 !(status & CTS));
372
373 wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
374 }
375
376 if (status & BRK_ABRT)
377 uap->flags |= PMACZILOG_FLAG_BREAK;
378
379 uap->prev_status = status;
380}
381
382static void pmz_transmit_chars(struct uart_pmac_port *uap)
383{
384 struct circ_buf *xmit;
385
386 if (ZS_IS_ASLEEP(uap))
387 return;
388 if (ZS_IS_CONS(uap)) {
389 unsigned char status = read_zsreg(uap, R0);
390
391 /* TX still busy? Just wait for the next TX done interrupt.
392 *
393 * It can occur because of how we do serial console writes. It would
394 * be nice to transmit console writes just like we normally would for
395 * a TTY line. (ie. buffered and TX interrupt driven). That is not
396 * easy because console writes cannot sleep. One solution might be
397 * to poll on enough port->xmit space becoming free. -DaveM
398 */
399 if (!(status & Tx_BUF_EMP))
400 return;
401 }
402
403 uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
404
405 if (ZS_REGS_HELD(uap)) {
406 pmz_load_zsregs(uap, uap->curregs);
407 uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
408 }
409
410 if (ZS_TX_STOPPED(uap)) {
411 uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
412 goto ack_tx_int;
413 }
414
415 /* Under some circumstances, we see interrupts reported for
416 * a closed channel. The interrupt mask in R1 is clear, but
417 * R3 still signals the interrupts and we see them when taking
418 * an interrupt for the other channel (this could be a qemu
419 * bug but since the ESCC doc doesn't specify precsiely whether
420 * R3 interrup status bits are masked by R1 interrupt enable
421 * bits, better safe than sorry). --BenH.
422 */
423 if (!ZS_IS_OPEN(uap))
424 goto ack_tx_int;
425
426 if (uap->port.x_char) {
427 uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
428 write_zsdata(uap, uap->port.x_char);
429 zssync(uap);
430 uap->port.icount.tx++;
431 uap->port.x_char = 0;
432 return;
433 }
434
435 if (uap->port.state == NULL)
436 goto ack_tx_int;
437 xmit = &uap->port.state->xmit;
438 if (uart_circ_empty(xmit)) {
439 uart_write_wakeup(&uap->port);
440 goto ack_tx_int;
441 }
442 if (uart_tx_stopped(&uap->port))
443 goto ack_tx_int;
444
445 uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
446 write_zsdata(uap, xmit->buf[xmit->tail]);
447 zssync(uap);
448
449 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
450 uap->port.icount.tx++;
451
452 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
453 uart_write_wakeup(&uap->port);
454
455 return;
456
457ack_tx_int:
458 write_zsreg(uap, R0, RES_Tx_P);
459 zssync(uap);
460}
461
462/* Hrm... we register that twice, fixme later.... */
463static irqreturn_t pmz_interrupt(int irq, void *dev_id)
464{
465 struct uart_pmac_port *uap = dev_id;
466 struct uart_pmac_port *uap_a;
467 struct uart_pmac_port *uap_b;
468 int rc = IRQ_NONE;
469 struct tty_struct *tty;
470 u8 r3;
471
472 uap_a = pmz_get_port_A(uap);
473 uap_b = uap_a->mate;
474
475 spin_lock(&uap_a->port.lock);
476 r3 = read_zsreg(uap_a, R3);
477
478#ifdef DEBUG_HARD
479 pmz_debug("irq, r3: %x\n", r3);
480#endif
481 /* Channel A */
482 tty = NULL;
483 if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
484 write_zsreg(uap_a, R0, RES_H_IUS);
485 zssync(uap_a);
486 if (r3 & CHAEXT)
487 pmz_status_handle(uap_a);
488 if (r3 & CHARxIP)
489 tty = pmz_receive_chars(uap_a);
490 if (r3 & CHATxIP)
491 pmz_transmit_chars(uap_a);
492 rc = IRQ_HANDLED;
493 }
494 spin_unlock(&uap_a->port.lock);
495 if (tty != NULL)
496 tty_flip_buffer_push(tty);
497
498 if (uap_b->node == NULL)
499 goto out;
500
501 spin_lock(&uap_b->port.lock);
502 tty = NULL;
503 if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
504 write_zsreg(uap_b, R0, RES_H_IUS);
505 zssync(uap_b);
506 if (r3 & CHBEXT)
507 pmz_status_handle(uap_b);
508 if (r3 & CHBRxIP)
509 tty = pmz_receive_chars(uap_b);
510 if (r3 & CHBTxIP)
511 pmz_transmit_chars(uap_b);
512 rc = IRQ_HANDLED;
513 }
514 spin_unlock(&uap_b->port.lock);
515 if (tty != NULL)
516 tty_flip_buffer_push(tty);
517
518 out:
519#ifdef DEBUG_HARD
520 pmz_debug("irq done.\n");
521#endif
522 return rc;
523}
524
525/*
526 * Peek the status register, lock not held by caller
527 */
528static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
529{
530 unsigned long flags;
531 u8 status;
532
533 spin_lock_irqsave(&uap->port.lock, flags);
534 status = read_zsreg(uap, R0);
535 spin_unlock_irqrestore(&uap->port.lock, flags);
536
537 return status;
538}
539
540/*
541 * Check if transmitter is empty
542 * The port lock is not held.
543 */
544static unsigned int pmz_tx_empty(struct uart_port *port)
545{
546 struct uart_pmac_port *uap = to_pmz(port);
547 unsigned char status;
548
549 if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
550 return TIOCSER_TEMT;
551
552 status = pmz_peek_status(to_pmz(port));
553 if (status & Tx_BUF_EMP)
554 return TIOCSER_TEMT;
555 return 0;
556}
557
558/*
559 * Set Modem Control (RTS & DTR) bits
560 * The port lock is held and interrupts are disabled.
561 * Note: Shall we really filter out RTS on external ports or
562 * should that be dealt at higher level only ?
563 */
564static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
565{
566 struct uart_pmac_port *uap = to_pmz(port);
567 unsigned char set_bits, clear_bits;
568
569 /* Do nothing for irda for now... */
570 if (ZS_IS_IRDA(uap))
571 return;
572 /* We get called during boot with a port not up yet */
573 if (ZS_IS_ASLEEP(uap) ||
574 !(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
575 return;
576
577 set_bits = clear_bits = 0;
578
579 if (ZS_IS_INTMODEM(uap)) {
580 if (mctrl & TIOCM_RTS)
581 set_bits |= RTS;
582 else
583 clear_bits |= RTS;
584 }
585 if (mctrl & TIOCM_DTR)
586 set_bits |= DTR;
587 else
588 clear_bits |= DTR;
589
590 /* NOTE: Not subject to 'transmitter active' rule. */
591 uap->curregs[R5] |= set_bits;
592 uap->curregs[R5] &= ~clear_bits;
593 if (ZS_IS_ASLEEP(uap))
594 return;
595 write_zsreg(uap, R5, uap->curregs[R5]);
596 pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
597 set_bits, clear_bits, uap->curregs[R5]);
598 zssync(uap);
599}
600
601/*
602 * Get Modem Control bits (only the input ones, the core will
603 * or that with a cached value of the control ones)
604 * The port lock is held and interrupts are disabled.
605 */
606static unsigned int pmz_get_mctrl(struct uart_port *port)
607{
608 struct uart_pmac_port *uap = to_pmz(port);
609 unsigned char status;
610 unsigned int ret;
611
612 if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
613 return 0;
614
615 status = read_zsreg(uap, R0);
616
617 ret = 0;
618 if (status & DCD)
619 ret |= TIOCM_CAR;
620 if (status & SYNC_HUNT)
621 ret |= TIOCM_DSR;
622 if (!(status & CTS))
623 ret |= TIOCM_CTS;
624
625 return ret;
626}
627
628/*
629 * Stop TX side. Dealt like sunzilog at next Tx interrupt,
630 * though for DMA, we will have to do a bit more.
631 * The port lock is held and interrupts are disabled.
632 */
633static void pmz_stop_tx(struct uart_port *port)
634{
635 to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
636}
637
638/*
639 * Kick the Tx side.
640 * The port lock is held and interrupts are disabled.
641 */
642static void pmz_start_tx(struct uart_port *port)
643{
644 struct uart_pmac_port *uap = to_pmz(port);
645 unsigned char status;
646
647 pmz_debug("pmz: start_tx()\n");
648
649 uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
650 uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
651
652 if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
653 return;
654
655 status = read_zsreg(uap, R0);
656
657 /* TX busy? Just wait for the TX done interrupt. */
658 if (!(status & Tx_BUF_EMP))
659 return;
660
661 /* Send the first character to jump-start the TX done
662 * IRQ sending engine.
663 */
664 if (port->x_char) {
665 write_zsdata(uap, port->x_char);
666 zssync(uap);
667 port->icount.tx++;
668 port->x_char = 0;
669 } else {
670 struct circ_buf *xmit = &port->state->xmit;
671
672 write_zsdata(uap, xmit->buf[xmit->tail]);
673 zssync(uap);
674 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
675 port->icount.tx++;
676
677 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
678 uart_write_wakeup(&uap->port);
679 }
680 pmz_debug("pmz: start_tx() done.\n");
681}
682
683/*
684 * Stop Rx side, basically disable emitting of
685 * Rx interrupts on the port. We don't disable the rx
686 * side of the chip proper though
687 * The port lock is held.
688 */
689static void pmz_stop_rx(struct uart_port *port)
690{
691 struct uart_pmac_port *uap = to_pmz(port);
692
693 if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
694 return;
695
696 pmz_debug("pmz: stop_rx()()\n");
697
698 /* Disable all RX interrupts. */
699 uap->curregs[R1] &= ~RxINT_MASK;
700 pmz_maybe_update_regs(uap);
701
702 pmz_debug("pmz: stop_rx() done.\n");
703}
704
705/*
706 * Enable modem status change interrupts
707 * The port lock is held.
708 */
709static void pmz_enable_ms(struct uart_port *port)
710{
711 struct uart_pmac_port *uap = to_pmz(port);
712 unsigned char new_reg;
713
714 if (ZS_IS_IRDA(uap) || uap->node == NULL)
715 return;
716 new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
717 if (new_reg != uap->curregs[R15]) {
718 uap->curregs[R15] = new_reg;
719
720 if (ZS_IS_ASLEEP(uap))
721 return;
722 /* NOTE: Not subject to 'transmitter active' rule. */
723 write_zsreg(uap, R15, uap->curregs[R15]);
724 }
725}
726
727/*
728 * Control break state emission
729 * The port lock is not held.
730 */
731static void pmz_break_ctl(struct uart_port *port, int break_state)
732{
733 struct uart_pmac_port *uap = to_pmz(port);
734 unsigned char set_bits, clear_bits, new_reg;
735 unsigned long flags;
736
737 if (uap->node == NULL)
738 return;
739 set_bits = clear_bits = 0;
740
741 if (break_state)
742 set_bits |= SND_BRK;
743 else
744 clear_bits |= SND_BRK;
745
746 spin_lock_irqsave(&port->lock, flags);
747
748 new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
749 if (new_reg != uap->curregs[R5]) {
750 uap->curregs[R5] = new_reg;
751
752 /* NOTE: Not subject to 'transmitter active' rule. */
753 if (ZS_IS_ASLEEP(uap)) {
754 spin_unlock_irqrestore(&port->lock, flags);
755 return;
756 }
757 write_zsreg(uap, R5, uap->curregs[R5]);
758 }
759
760 spin_unlock_irqrestore(&port->lock, flags);
761}
762
763#ifdef CONFIG_PPC_PMAC
764
765/*
766 * Turn power on or off to the SCC and associated stuff
767 * (port drivers, modem, IR port, etc.)
768 * Returns the number of milliseconds we should wait before
769 * trying to use the port.
770 */
771static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
772{
773 int delay = 0;
774 int rc;
775
776 if (state) {
777 rc = pmac_call_feature(
778 PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
779 pmz_debug("port power on result: %d\n", rc);
780 if (ZS_IS_INTMODEM(uap)) {
781 rc = pmac_call_feature(
782 PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
783 delay = 2500; /* wait for 2.5s before using */
784 pmz_debug("modem power result: %d\n", rc);
785 }
786 } else {
787 /* TODO: Make that depend on a timer, don't power down
788 * immediately
789 */
790 if (ZS_IS_INTMODEM(uap)) {
791 rc = pmac_call_feature(
792 PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
793 pmz_debug("port power off result: %d\n", rc);
794 }
795 pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
796 }
797 return delay;
798}
799
800#else
801
802static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
803{
804 return 0;
805}
806
807#endif /* !CONFIG_PPC_PMAC */
808
809/*
810 * FixZeroBug....Works around a bug in the SCC receiving channel.
811 * Inspired from Darwin code, 15 Sept. 2000 -DanM
812 *
813 * The following sequence prevents a problem that is seen with O'Hare ASICs
814 * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
815 * at the input to the receiver becomes 'stuck' and locks up the receiver.
816 * This problem can occur as a result of a zero bit at the receiver input
817 * coincident with any of the following events:
818 *
819 * The SCC is initialized (hardware or software).
820 * A framing error is detected.
821 * The clocking option changes from synchronous or X1 asynchronous
822 * clocking to X16, X32, or X64 asynchronous clocking.
823 * The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
824 *
825 * This workaround attempts to recover from the lockup condition by placing
826 * the SCC in synchronous loopback mode with a fast clock before programming
827 * any of the asynchronous modes.
828 */
829static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
830{
831 write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
832 zssync(uap);
833 udelay(10);
834 write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
835 zssync(uap);
836
837 write_zsreg(uap, 4, X1CLK | MONSYNC);
838 write_zsreg(uap, 3, Rx8);
839 write_zsreg(uap, 5, Tx8 | RTS);
840 write_zsreg(uap, 9, NV); /* Didn't we already do this? */
841 write_zsreg(uap, 11, RCBR | TCBR);
842 write_zsreg(uap, 12, 0);
843 write_zsreg(uap, 13, 0);
844 write_zsreg(uap, 14, (LOOPBAK | BRSRC));
845 write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
846 write_zsreg(uap, 3, Rx8 | RxENABLE);
847 write_zsreg(uap, 0, RES_EXT_INT);
848 write_zsreg(uap, 0, RES_EXT_INT);
849 write_zsreg(uap, 0, RES_EXT_INT); /* to kill some time */
850
851 /* The channel should be OK now, but it is probably receiving
852 * loopback garbage.
853 * Switch to asynchronous mode, disable the receiver,
854 * and discard everything in the receive buffer.
855 */
856 write_zsreg(uap, 9, NV);
857 write_zsreg(uap, 4, X16CLK | SB_MASK);
858 write_zsreg(uap, 3, Rx8);
859
860 while (read_zsreg(uap, 0) & Rx_CH_AV) {
861 (void)read_zsreg(uap, 8);
862 write_zsreg(uap, 0, RES_EXT_INT);
863 write_zsreg(uap, 0, ERR_RES);
864 }
865}
866
867/*
868 * Real startup routine, powers up the hardware and sets up
869 * the SCC. Returns a delay in ms where you need to wait before
870 * actually using the port, this is typically the internal modem
871 * powerup delay. This routine expect the lock to be taken.
872 */
873static int __pmz_startup(struct uart_pmac_port *uap)
874{
875 int pwr_delay = 0;
876
877 memset(&uap->curregs, 0, sizeof(uap->curregs));
878
879 /* Power up the SCC & underlying hardware (modem/irda) */
880 pwr_delay = pmz_set_scc_power(uap, 1);
881
882 /* Nice buggy HW ... */
883 pmz_fix_zero_bug_scc(uap);
884
885 /* Reset the channel */
886 uap->curregs[R9] = 0;
887 write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
888 zssync(uap);
889 udelay(10);
890 write_zsreg(uap, 9, 0);
891 zssync(uap);
892
893 /* Clear the interrupt registers */
894 write_zsreg(uap, R1, 0);
895 write_zsreg(uap, R0, ERR_RES);
896 write_zsreg(uap, R0, ERR_RES);
897 write_zsreg(uap, R0, RES_H_IUS);
898 write_zsreg(uap, R0, RES_H_IUS);
899
900 /* Setup some valid baud rate */
901 uap->curregs[R4] = X16CLK | SB1;
902 uap->curregs[R3] = Rx8;
903 uap->curregs[R5] = Tx8 | RTS;
904 if (!ZS_IS_IRDA(uap))
905 uap->curregs[R5] |= DTR;
906 uap->curregs[R12] = 0;
907 uap->curregs[R13] = 0;
908 uap->curregs[R14] = BRENAB;
909
910 /* Clear handshaking, enable BREAK interrupts */
911 uap->curregs[R15] = BRKIE;
912
913 /* Master interrupt enable */
914 uap->curregs[R9] |= NV | MIE;
915
916 pmz_load_zsregs(uap, uap->curregs);
917
918 /* Enable receiver and transmitter. */
919 write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
920 write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
921
922 /* Remember status for DCD/CTS changes */
923 uap->prev_status = read_zsreg(uap, R0);
924
925 return pwr_delay;
926}
927
928static void pmz_irda_reset(struct uart_pmac_port *uap)
929{
930 uap->curregs[R5] |= DTR;
931 write_zsreg(uap, R5, uap->curregs[R5]);
932 zssync(uap);
933 mdelay(110);
934 uap->curregs[R5] &= ~DTR;
935 write_zsreg(uap, R5, uap->curregs[R5]);
936 zssync(uap);
937 mdelay(10);
938}
939
940/*
941 * This is the "normal" startup routine, using the above one
942 * wrapped with the lock and doing a schedule delay
943 */
944static int pmz_startup(struct uart_port *port)
945{
946 struct uart_pmac_port *uap = to_pmz(port);
947 unsigned long flags;
948 int pwr_delay = 0;
949
950 pmz_debug("pmz: startup()\n");
951
952 if (ZS_IS_ASLEEP(uap))
953 return -EAGAIN;
954 if (uap->node == NULL)
955 return -ENODEV;
956
957 mutex_lock(&pmz_irq_mutex);
958
959 uap->flags |= PMACZILOG_FLAG_IS_OPEN;
960
961 /* A console is never powered down. Else, power up and
962 * initialize the chip
963 */
964 if (!ZS_IS_CONS(uap)) {
965 spin_lock_irqsave(&port->lock, flags);
966 pwr_delay = __pmz_startup(uap);
967 spin_unlock_irqrestore(&port->lock, flags);
968 }
969
970 pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
971 if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
972 "SCC", uap)) {
973 pmz_error("Unable to register zs interrupt handler.\n");
974 pmz_set_scc_power(uap, 0);
975 mutex_unlock(&pmz_irq_mutex);
976 return -ENXIO;
977 }
978
979 mutex_unlock(&pmz_irq_mutex);
980
981 /* Right now, we deal with delay by blocking here, I'll be
982 * smarter later on
983 */
984 if (pwr_delay != 0) {
985 pmz_debug("pmz: delaying %d ms\n", pwr_delay);
986 msleep(pwr_delay);
987 }
988
989 /* IrDA reset is done now */
990 if (ZS_IS_IRDA(uap))
991 pmz_irda_reset(uap);
992
993 /* Enable interrupts emission from the chip */
994 spin_lock_irqsave(&port->lock, flags);
995 uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
996 if (!ZS_IS_EXTCLK(uap))
997 uap->curregs[R1] |= EXT_INT_ENAB;
998 write_zsreg(uap, R1, uap->curregs[R1]);
999 spin_unlock_irqrestore(&port->lock, flags);
1000
1001 pmz_debug("pmz: startup() done.\n");
1002
1003 return 0;
1004}
1005
1006static void pmz_shutdown(struct uart_port *port)
1007{
1008 struct uart_pmac_port *uap = to_pmz(port);
1009 unsigned long flags;
1010
1011 pmz_debug("pmz: shutdown()\n");
1012
1013 if (uap->node == NULL)
1014 return;
1015
1016 mutex_lock(&pmz_irq_mutex);
1017
1018 /* Release interrupt handler */
1019 free_irq(uap->port.irq, uap);
1020
1021 spin_lock_irqsave(&port->lock, flags);
1022
1023 uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
1024
1025 if (!ZS_IS_OPEN(uap->mate))
1026 pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
1027
1028 /* Disable interrupts */
1029 if (!ZS_IS_ASLEEP(uap)) {
1030 uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
1031 write_zsreg(uap, R1, uap->curregs[R1]);
1032 zssync(uap);
1033 }
1034
1035 if (ZS_IS_CONS(uap) || ZS_IS_ASLEEP(uap)) {
1036 spin_unlock_irqrestore(&port->lock, flags);
1037 mutex_unlock(&pmz_irq_mutex);
1038 return;
1039 }
1040
1041 /* Disable receiver and transmitter. */
1042 uap->curregs[R3] &= ~RxENABLE;
1043 uap->curregs[R5] &= ~TxENABLE;
1044
1045 /* Disable all interrupts and BRK assertion. */
1046 uap->curregs[R5] &= ~SND_BRK;
1047 pmz_maybe_update_regs(uap);
1048
1049 /* Shut the chip down */
1050 pmz_set_scc_power(uap, 0);
1051
1052 spin_unlock_irqrestore(&port->lock, flags);
1053
1054 mutex_unlock(&pmz_irq_mutex);
1055
1056 pmz_debug("pmz: shutdown() done.\n");
1057}
1058
1059/* Shared by TTY driver and serial console setup. The port lock is held
1060 * and local interrupts are disabled.
1061 */
1062static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
1063 unsigned int iflag, unsigned long baud)
1064{
1065 int brg;
1066
1067 /* Switch to external clocking for IrDA high clock rates. That
1068 * code could be re-used for Midi interfaces with different
1069 * multipliers
1070 */
1071 if (baud >= 115200 && ZS_IS_IRDA(uap)) {
1072 uap->curregs[R4] = X1CLK;
1073 uap->curregs[R11] = RCTRxCP | TCTRxCP;
1074 uap->curregs[R14] = 0; /* BRG off */
1075 uap->curregs[R12] = 0;
1076 uap->curregs[R13] = 0;
1077 uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
1078 } else {
1079 switch (baud) {
1080 case ZS_CLOCK/16: /* 230400 */
1081 uap->curregs[R4] = X16CLK;
1082 uap->curregs[R11] = 0;
1083 uap->curregs[R14] = 0;
1084 break;
1085 case ZS_CLOCK/32: /* 115200 */
1086 uap->curregs[R4] = X32CLK;
1087 uap->curregs[R11] = 0;
1088 uap->curregs[R14] = 0;
1089 break;
1090 default:
1091 uap->curregs[R4] = X16CLK;
1092 uap->curregs[R11] = TCBR | RCBR;
1093 brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
1094 uap->curregs[R12] = (brg & 255);
1095 uap->curregs[R13] = ((brg >> 8) & 255);
1096 uap->curregs[R14] = BRENAB;
1097 }
1098 uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
1099 }
1100
1101 /* Character size, stop bits, and parity. */
1102 uap->curregs[3] &= ~RxN_MASK;
1103 uap->curregs[5] &= ~TxN_MASK;
1104
1105 switch (cflag & CSIZE) {
1106 case CS5:
1107 uap->curregs[3] |= Rx5;
1108 uap->curregs[5] |= Tx5;
1109 uap->parity_mask = 0x1f;
1110 break;
1111 case CS6:
1112 uap->curregs[3] |= Rx6;
1113 uap->curregs[5] |= Tx6;
1114 uap->parity_mask = 0x3f;
1115 break;
1116 case CS7:
1117 uap->curregs[3] |= Rx7;
1118 uap->curregs[5] |= Tx7;
1119 uap->parity_mask = 0x7f;
1120 break;
1121 case CS8:
1122 default:
1123 uap->curregs[3] |= Rx8;
1124 uap->curregs[5] |= Tx8;
1125 uap->parity_mask = 0xff;
1126 break;
1127 };
1128 uap->curregs[4] &= ~(SB_MASK);
1129 if (cflag & CSTOPB)
1130 uap->curregs[4] |= SB2;
1131 else
1132 uap->curregs[4] |= SB1;
1133 if (cflag & PARENB)
1134 uap->curregs[4] |= PAR_ENAB;
1135 else
1136 uap->curregs[4] &= ~PAR_ENAB;
1137 if (!(cflag & PARODD))
1138 uap->curregs[4] |= PAR_EVEN;
1139 else
1140 uap->curregs[4] &= ~PAR_EVEN;
1141
1142 uap->port.read_status_mask = Rx_OVR;
1143 if (iflag & INPCK)
1144 uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1145 if (iflag & (BRKINT | PARMRK))
1146 uap->port.read_status_mask |= BRK_ABRT;
1147
1148 uap->port.ignore_status_mask = 0;
1149 if (iflag & IGNPAR)
1150 uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1151 if (iflag & IGNBRK) {
1152 uap->port.ignore_status_mask |= BRK_ABRT;
1153 if (iflag & IGNPAR)
1154 uap->port.ignore_status_mask |= Rx_OVR;
1155 }
1156
1157 if ((cflag & CREAD) == 0)
1158 uap->port.ignore_status_mask = 0xff;
1159}
1160
1161
1162/*
1163 * Set the irda codec on the imac to the specified baud rate.
1164 */
1165static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1166{
1167 u8 cmdbyte;
1168 int t, version;
1169
1170 switch (*baud) {
1171 /* SIR modes */
1172 case 2400:
1173 cmdbyte = 0x53;
1174 break;
1175 case 4800:
1176 cmdbyte = 0x52;
1177 break;
1178 case 9600:
1179 cmdbyte = 0x51;
1180 break;
1181 case 19200:
1182 cmdbyte = 0x50;
1183 break;
1184 case 38400:
1185 cmdbyte = 0x4f;
1186 break;
1187 case 57600:
1188 cmdbyte = 0x4e;
1189 break;
1190 case 115200:
1191 cmdbyte = 0x4d;
1192 break;
1193 /* The FIR modes aren't really supported at this point, how
1194 * do we select the speed ? via the FCR on KeyLargo ?
1195 */
1196 case 1152000:
1197 cmdbyte = 0;
1198 break;
1199 case 4000000:
1200 cmdbyte = 0;
1201 break;
1202 default: /* 9600 */
1203 cmdbyte = 0x51;
1204 *baud = 9600;
1205 break;
1206 }
1207
1208 /* Wait for transmitter to drain */
1209 t = 10000;
1210 while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1211 || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1212 if (--t <= 0) {
1213 pmz_error("transmitter didn't drain\n");
1214 return;
1215 }
1216 udelay(10);
1217 }
1218
1219 /* Drain the receiver too */
1220 t = 100;
1221 (void)read_zsdata(uap);
1222 (void)read_zsdata(uap);
1223 (void)read_zsdata(uap);
1224 mdelay(10);
1225 while (read_zsreg(uap, R0) & Rx_CH_AV) {
1226 read_zsdata(uap);
1227 mdelay(10);
1228 if (--t <= 0) {
1229 pmz_error("receiver didn't drain\n");
1230 return;
1231 }
1232 }
1233
1234 /* Switch to command mode */
1235 uap->curregs[R5] |= DTR;
1236 write_zsreg(uap, R5, uap->curregs[R5]);
1237 zssync(uap);
1238 mdelay(1);
1239
1240 /* Switch SCC to 19200 */
1241 pmz_convert_to_zs(uap, CS8, 0, 19200);
1242 pmz_load_zsregs(uap, uap->curregs);
1243 mdelay(1);
1244
1245 /* Write get_version command byte */
1246 write_zsdata(uap, 1);
1247 t = 5000;
1248 while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1249 if (--t <= 0) {
1250 pmz_error("irda_setup timed out on get_version byte\n");
1251 goto out;
1252 }
1253 udelay(10);
1254 }
1255 version = read_zsdata(uap);
1256
1257 if (version < 4) {
1258 pmz_info("IrDA: dongle version %d not supported\n", version);
1259 goto out;
1260 }
1261
1262 /* Send speed mode */
1263 write_zsdata(uap, cmdbyte);
1264 t = 5000;
1265 while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1266 if (--t <= 0) {
1267 pmz_error("irda_setup timed out on speed mode byte\n");
1268 goto out;
1269 }
1270 udelay(10);
1271 }
1272 t = read_zsdata(uap);
1273 if (t != cmdbyte)
1274 pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1275
1276 pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1277 *baud, version);
1278
1279 (void)read_zsdata(uap);
1280 (void)read_zsdata(uap);
1281 (void)read_zsdata(uap);
1282
1283 out:
1284 /* Switch back to data mode */
1285 uap->curregs[R5] &= ~DTR;
1286 write_zsreg(uap, R5, uap->curregs[R5]);
1287 zssync(uap);
1288
1289 (void)read_zsdata(uap);
1290 (void)read_zsdata(uap);
1291 (void)read_zsdata(uap);
1292}
1293
1294
1295static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1296 struct ktermios *old)
1297{
1298 struct uart_pmac_port *uap = to_pmz(port);
1299 unsigned long baud;
1300
1301 pmz_debug("pmz: set_termios()\n");
1302
1303 if (ZS_IS_ASLEEP(uap))
1304 return;
1305
1306 memcpy(&uap->termios_cache, termios, sizeof(struct ktermios));
1307
1308 /* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1309 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1310 * about the FIR mode and high speed modes. So these are unused. For
1311 * implementing proper support for these, we should probably add some
1312 * DMA as well, at least on the Rx side, which isn't a simple thing
1313 * at this point.
1314 */
1315 if (ZS_IS_IRDA(uap)) {
1316 /* Calc baud rate */
1317 baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1318 pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1319 /* Cet the irda codec to the right rate */
1320 pmz_irda_setup(uap, &baud);
1321 /* Set final baud rate */
1322 pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1323 pmz_load_zsregs(uap, uap->curregs);
1324 zssync(uap);
1325 } else {
1326 baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1327 pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1328 /* Make sure modem status interrupts are correctly configured */
1329 if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1330 uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1331 uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1332 } else {
1333 uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1334 uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1335 }
1336
1337 /* Load registers to the chip */
1338 pmz_maybe_update_regs(uap);
1339 }
1340 uart_update_timeout(port, termios->c_cflag, baud);
1341
1342 pmz_debug("pmz: set_termios() done.\n");
1343}
1344
1345/* The port lock is not held. */
1346static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1347 struct ktermios *old)
1348{
1349 struct uart_pmac_port *uap = to_pmz(port);
1350 unsigned long flags;
1351
1352 spin_lock_irqsave(&port->lock, flags);
1353
1354 /* Disable IRQs on the port */
1355 uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
1356 write_zsreg(uap, R1, uap->curregs[R1]);
1357
1358 /* Setup new port configuration */
1359 __pmz_set_termios(port, termios, old);
1360
1361 /* Re-enable IRQs on the port */
1362 if (ZS_IS_OPEN(uap)) {
1363 uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
1364 if (!ZS_IS_EXTCLK(uap))
1365 uap->curregs[R1] |= EXT_INT_ENAB;
1366 write_zsreg(uap, R1, uap->curregs[R1]);
1367 }
1368 spin_unlock_irqrestore(&port->lock, flags);
1369}
1370
1371static const char *pmz_type(struct uart_port *port)
1372{
1373 struct uart_pmac_port *uap = to_pmz(port);
1374
1375 if (ZS_IS_IRDA(uap))
1376 return "Z85c30 ESCC - Infrared port";
1377 else if (ZS_IS_INTMODEM(uap))
1378 return "Z85c30 ESCC - Internal modem";
1379 return "Z85c30 ESCC - Serial port";
1380}
1381
1382/* We do not request/release mappings of the registers here, this
1383 * happens at early serial probe time.
1384 */
1385static void pmz_release_port(struct uart_port *port)
1386{
1387}
1388
1389static int pmz_request_port(struct uart_port *port)
1390{
1391 return 0;
1392}
1393
1394/* These do not need to do anything interesting either. */
1395static void pmz_config_port(struct uart_port *port, int flags)
1396{
1397}
1398
1399/* We do not support letting the user mess with the divisor, IRQ, etc. */
1400static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1401{
1402 return -EINVAL;
1403}
1404
1405#ifdef CONFIG_CONSOLE_POLL
1406
1407static int pmz_poll_get_char(struct uart_port *port)
1408{
1409 struct uart_pmac_port *uap = (struct uart_pmac_port *)port;
1410
1411 while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0)
1412 udelay(5);
1413 return read_zsdata(uap);
1414}
1415
1416static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1417{
1418 struct uart_pmac_port *uap = (struct uart_pmac_port *)port;
1419
1420 /* Wait for the transmit buffer to empty. */
1421 while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1422 udelay(5);
1423 write_zsdata(uap, c);
1424}
1425
1426#endif /* CONFIG_CONSOLE_POLL */
1427
1428static struct uart_ops pmz_pops = {
1429 .tx_empty = pmz_tx_empty,
1430 .set_mctrl = pmz_set_mctrl,
1431 .get_mctrl = pmz_get_mctrl,
1432 .stop_tx = pmz_stop_tx,
1433 .start_tx = pmz_start_tx,
1434 .stop_rx = pmz_stop_rx,
1435 .enable_ms = pmz_enable_ms,
1436 .break_ctl = pmz_break_ctl,
1437 .startup = pmz_startup,
1438 .shutdown = pmz_shutdown,
1439 .set_termios = pmz_set_termios,
1440 .type = pmz_type,
1441 .release_port = pmz_release_port,
1442 .request_port = pmz_request_port,
1443 .config_port = pmz_config_port,
1444 .verify_port = pmz_verify_port,
1445#ifdef CONFIG_CONSOLE_POLL
1446 .poll_get_char = pmz_poll_get_char,
1447 .poll_put_char = pmz_poll_put_char,
1448#endif
1449};
1450
1451#ifdef CONFIG_PPC_PMAC
1452
1453/*
1454 * Setup one port structure after probing, HW is down at this point,
1455 * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1456 * register our console before uart_add_one_port() is called
1457 */
1458static int __init pmz_init_port(struct uart_pmac_port *uap)
1459{
1460 struct device_node *np = uap->node;
1461 const char *conn;
1462 const struct slot_names_prop {
1463 int count;
1464 char name[1];
1465 } *slots;
1466 int len;
1467 struct resource r_ports, r_rxdma, r_txdma;
1468
1469 /*
1470 * Request & map chip registers
1471 */
1472 if (of_address_to_resource(np, 0, &r_ports))
1473 return -ENODEV;
1474 uap->port.mapbase = r_ports.start;
1475 uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1476
1477 uap->control_reg = uap->port.membase;
1478 uap->data_reg = uap->control_reg + 0x10;
1479
1480 /*
1481 * Request & map DBDMA registers
1482 */
1483#ifdef HAS_DBDMA
1484 if (of_address_to_resource(np, 1, &r_txdma) == 0 &&
1485 of_address_to_resource(np, 2, &r_rxdma) == 0)
1486 uap->flags |= PMACZILOG_FLAG_HAS_DMA;
1487#else
1488 memset(&r_txdma, 0, sizeof(struct resource));
1489 memset(&r_rxdma, 0, sizeof(struct resource));
1490#endif
1491 if (ZS_HAS_DMA(uap)) {
1492 uap->tx_dma_regs = ioremap(r_txdma.start, 0x100);
1493 if (uap->tx_dma_regs == NULL) {
1494 uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1495 goto no_dma;
1496 }
1497 uap->rx_dma_regs = ioremap(r_rxdma.start, 0x100);
1498 if (uap->rx_dma_regs == NULL) {
1499 iounmap(uap->tx_dma_regs);
1500 uap->tx_dma_regs = NULL;
1501 uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1502 goto no_dma;
1503 }
1504 uap->tx_dma_irq = irq_of_parse_and_map(np, 1);
1505 uap->rx_dma_irq = irq_of_parse_and_map(np, 2);
1506 }
1507no_dma:
1508
1509 /*
1510 * Detect port type
1511 */
1512 if (of_device_is_compatible(np, "cobalt"))
1513 uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1514 conn = of_get_property(np, "AAPL,connector", &len);
1515 if (conn && (strcmp(conn, "infrared") == 0))
1516 uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1517 uap->port_type = PMAC_SCC_ASYNC;
1518 /* 1999 Powerbook G3 has slot-names property instead */
1519 slots = of_get_property(np, "slot-names", &len);
1520 if (slots && slots->count > 0) {
1521 if (strcmp(slots->name, "IrDA") == 0)
1522 uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1523 else if (strcmp(slots->name, "Modem") == 0)
1524 uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1525 }
1526 if (ZS_IS_IRDA(uap))
1527 uap->port_type = PMAC_SCC_IRDA;
1528 if (ZS_IS_INTMODEM(uap)) {
1529 struct device_node* i2c_modem =
1530 of_find_node_by_name(NULL, "i2c-modem");
1531 if (i2c_modem) {
1532 const char* mid =
1533 of_get_property(i2c_modem, "modem-id", NULL);
1534 if (mid) switch(*mid) {
1535 case 0x04 :
1536 case 0x05 :
1537 case 0x07 :
1538 case 0x08 :
1539 case 0x0b :
1540 case 0x0c :
1541 uap->port_type = PMAC_SCC_I2S1;
1542 }
1543 printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1544 mid ? (*mid) : 0);
1545 of_node_put(i2c_modem);
1546 } else {
1547 printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1548 }
1549 }
1550
1551 /*
1552 * Init remaining bits of "port" structure
1553 */
1554 uap->port.iotype = UPIO_MEM;
1555 uap->port.irq = irq_of_parse_and_map(np, 0);
1556 uap->port.uartclk = ZS_CLOCK;
1557 uap->port.fifosize = 1;
1558 uap->port.ops = &pmz_pops;
1559 uap->port.type = PORT_PMAC_ZILOG;
1560 uap->port.flags = 0;
1561
1562 /*
1563 * Fixup for the port on Gatwick for which the device-tree has
1564 * missing interrupts. Normally, the macio_dev would contain
1565 * fixed up interrupt info, but we use the device-tree directly
1566 * here due to early probing so we need the fixup too.
1567 */
1568 if (uap->port.irq == NO_IRQ &&
1569 np->parent && np->parent->parent &&
1570 of_device_is_compatible(np->parent->parent, "gatwick")) {
1571 /* IRQs on gatwick are offset by 64 */
1572 uap->port.irq = irq_create_mapping(NULL, 64 + 15);
1573 uap->tx_dma_irq = irq_create_mapping(NULL, 64 + 4);
1574 uap->rx_dma_irq = irq_create_mapping(NULL, 64 + 5);
1575 }
1576
1577 /* Setup some valid baud rate information in the register
1578 * shadows so we don't write crap there before baud rate is
1579 * first initialized.
1580 */
1581 pmz_convert_to_zs(uap, CS8, 0, 9600);
1582
1583 return 0;
1584}
1585
1586/*
1587 * Get rid of a port on module removal
1588 */
1589static void pmz_dispose_port(struct uart_pmac_port *uap)
1590{
1591 struct device_node *np;
1592
1593 np = uap->node;
1594 iounmap(uap->rx_dma_regs);
1595 iounmap(uap->tx_dma_regs);
1596 iounmap(uap->control_reg);
1597 uap->node = NULL;
1598 of_node_put(np);
1599 memset(uap, 0, sizeof(struct uart_pmac_port));
1600}
1601
1602/*
1603 * Called upon match with an escc node in the device-tree.
1604 */
1605static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1606{
1607 int i;
1608
1609 /* Iterate the pmz_ports array to find a matching entry
1610 */
1611 for (i = 0; i < MAX_ZS_PORTS; i++)
1612 if (pmz_ports[i].node == mdev->ofdev.dev.of_node) {
1613 struct uart_pmac_port *uap = &pmz_ports[i];
1614
1615 uap->dev = mdev;
1616 dev_set_drvdata(&mdev->ofdev.dev, uap);
1617 if (macio_request_resources(uap->dev, "pmac_zilog"))
1618 printk(KERN_WARNING "%s: Failed to request resource"
1619 ", port still active\n",
1620 uap->node->name);
1621 else
1622 uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1623 return 0;
1624 }
1625 return -ENODEV;
1626}
1627
1628/*
1629 * That one should not be called, macio isn't really a hotswap device,
1630 * we don't expect one of those serial ports to go away...
1631 */
1632static int pmz_detach(struct macio_dev *mdev)
1633{
1634 struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1635
1636 if (!uap)
1637 return -ENODEV;
1638
1639 if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1640 macio_release_resources(uap->dev);
1641 uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1642 }
1643 dev_set_drvdata(&mdev->ofdev.dev, NULL);
1644 uap->dev = NULL;
1645
1646 return 0;
1647}
1648
1649
1650static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1651{
1652 struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1653 struct uart_state *state;
1654 unsigned long flags;
1655
1656 if (uap == NULL) {
1657 printk("HRM... pmz_suspend with NULL uap\n");
1658 return 0;
1659 }
1660
1661 if (pm_state.event == mdev->ofdev.dev.power.power_state.event)
1662 return 0;
1663
1664 pmz_debug("suspend, switching to state %d\n", pm_state.event);
1665
1666 state = pmz_uart_reg.state + uap->port.line;
1667
1668 mutex_lock(&pmz_irq_mutex);
1669 mutex_lock(&state->port.mutex);
1670
1671 spin_lock_irqsave(&uap->port.lock, flags);
1672
1673 if (ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)) {
1674 /* Disable receiver and transmitter. */
1675 uap->curregs[R3] &= ~RxENABLE;
1676 uap->curregs[R5] &= ~TxENABLE;
1677
1678 /* Disable all interrupts and BRK assertion. */
1679 uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
1680 uap->curregs[R5] &= ~SND_BRK;
1681 pmz_load_zsregs(uap, uap->curregs);
1682 uap->flags |= PMACZILOG_FLAG_IS_ASLEEP;
1683 mb();
1684 }
1685
1686 spin_unlock_irqrestore(&uap->port.lock, flags);
1687
1688 if (ZS_IS_OPEN(uap) || ZS_IS_OPEN(uap->mate))
1689 if (ZS_IS_ASLEEP(uap->mate) && ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
1690 pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
1691 disable_irq(uap->port.irq);
1692 }
1693
1694 if (ZS_IS_CONS(uap))
1695 uap->port.cons->flags &= ~CON_ENABLED;
1696
1697 /* Shut the chip down */
1698 pmz_set_scc_power(uap, 0);
1699
1700 mutex_unlock(&state->port.mutex);
1701 mutex_unlock(&pmz_irq_mutex);
1702
1703 pmz_debug("suspend, switching complete\n");
1704
1705 mdev->ofdev.dev.power.power_state = pm_state;
1706
1707 return 0;
1708}
1709
1710
1711static int pmz_resume(struct macio_dev *mdev)
1712{
1713 struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1714 struct uart_state *state;
1715 unsigned long flags;
1716 int pwr_delay = 0;
1717
1718 if (uap == NULL)
1719 return 0;
1720
1721 if (mdev->ofdev.dev.power.power_state.event == PM_EVENT_ON)
1722 return 0;
1723
1724 pmz_debug("resume, switching to state 0\n");
1725
1726 state = pmz_uart_reg.state + uap->port.line;
1727
1728 mutex_lock(&pmz_irq_mutex);
1729 mutex_lock(&state->port.mutex);
1730
1731 spin_lock_irqsave(&uap->port.lock, flags);
1732 if (!ZS_IS_OPEN(uap) && !ZS_IS_CONS(uap)) {
1733 spin_unlock_irqrestore(&uap->port.lock, flags);
1734 goto bail;
1735 }
1736 pwr_delay = __pmz_startup(uap);
1737
1738 /* Take care of config that may have changed while asleep */
1739 __pmz_set_termios(&uap->port, &uap->termios_cache, NULL);
1740
1741 if (ZS_IS_OPEN(uap)) {
1742 /* Enable interrupts */
1743 uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
1744 if (!ZS_IS_EXTCLK(uap))
1745 uap->curregs[R1] |= EXT_INT_ENAB;
1746 write_zsreg(uap, R1, uap->curregs[R1]);
1747 }
1748
1749 spin_unlock_irqrestore(&uap->port.lock, flags);
1750
1751 if (ZS_IS_CONS(uap))
1752 uap->port.cons->flags |= CON_ENABLED;
1753
1754 /* Re-enable IRQ on the controller */
1755 if (ZS_IS_OPEN(uap) && !ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
1756 pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
1757 enable_irq(uap->port.irq);
1758 }
1759
1760 bail:
1761 mutex_unlock(&state->port.mutex);
1762 mutex_unlock(&pmz_irq_mutex);
1763
1764 /* Right now, we deal with delay by blocking here, I'll be
1765 * smarter later on
1766 */
1767 if (pwr_delay != 0) {
1768 pmz_debug("pmz: delaying %d ms\n", pwr_delay);
1769 msleep(pwr_delay);
1770 }
1771
1772 pmz_debug("resume, switching complete\n");
1773
1774 mdev->ofdev.dev.power.power_state.event = PM_EVENT_ON;
1775
1776 return 0;
1777}
1778
1779/*
1780 * Probe all ports in the system and build the ports array, we register
1781 * with the serial layer at this point, the macio-type probing is only
1782 * used later to "attach" to the sysfs tree so we get power management
1783 * events
1784 */
1785static int __init pmz_probe(void)
1786{
1787 struct device_node *node_p, *node_a, *node_b, *np;
1788 int count = 0;
1789 int rc;
1790
1791 /*
1792 * Find all escc chips in the system
1793 */
1794 node_p = of_find_node_by_name(NULL, "escc");
1795 while (node_p) {
1796 /*
1797 * First get channel A/B node pointers
1798 *
1799 * TODO: Add routines with proper locking to do that...
1800 */
1801 node_a = node_b = NULL;
1802 for (np = NULL; (np = of_get_next_child(node_p, np)) != NULL;) {
1803 if (strncmp(np->name, "ch-a", 4) == 0)
1804 node_a = of_node_get(np);
1805 else if (strncmp(np->name, "ch-b", 4) == 0)
1806 node_b = of_node_get(np);
1807 }
1808 if (!node_a && !node_b) {
1809 of_node_put(node_a);
1810 of_node_put(node_b);
1811 printk(KERN_ERR "pmac_zilog: missing node %c for escc %s\n",
1812 (!node_a) ? 'a' : 'b', node_p->full_name);
1813 goto next;
1814 }
1815
1816 /*
1817 * Fill basic fields in the port structures
1818 */
1819 pmz_ports[count].mate = &pmz_ports[count+1];
1820 pmz_ports[count+1].mate = &pmz_ports[count];
1821 pmz_ports[count].flags = PMACZILOG_FLAG_IS_CHANNEL_A;
1822 pmz_ports[count].node = node_a;
1823 pmz_ports[count+1].node = node_b;
1824 pmz_ports[count].port.line = count;
1825 pmz_ports[count+1].port.line = count+1;
1826
1827 /*
1828 * Setup the ports for real
1829 */
1830 rc = pmz_init_port(&pmz_ports[count]);
1831 if (rc == 0 && node_b != NULL)
1832 rc = pmz_init_port(&pmz_ports[count+1]);
1833 if (rc != 0) {
1834 of_node_put(node_a);
1835 of_node_put(node_b);
1836 memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1837 memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1838 goto next;
1839 }
1840 count += 2;
1841next:
1842 node_p = of_find_node_by_name(node_p, "escc");
1843 }
1844 pmz_ports_count = count;
1845
1846 return 0;
1847}
1848
1849#else
1850
1851extern struct platform_device scc_a_pdev, scc_b_pdev;
1852
1853static int __init pmz_init_port(struct uart_pmac_port *uap)
1854{
1855 struct resource *r_ports;
1856 int irq;
1857
1858 r_ports = platform_get_resource(uap->node, IORESOURCE_MEM, 0);
1859 irq = platform_get_irq(uap->node, 0);
1860 if (!r_ports || !irq)
1861 return -ENODEV;
1862
1863 uap->port.mapbase = r_ports->start;
1864 uap->port.membase = (unsigned char __iomem *) r_ports->start;
1865 uap->port.iotype = UPIO_MEM;
1866 uap->port.irq = irq;
1867 uap->port.uartclk = ZS_CLOCK;
1868 uap->port.fifosize = 1;
1869 uap->port.ops = &pmz_pops;
1870 uap->port.type = PORT_PMAC_ZILOG;
1871 uap->port.flags = 0;
1872
1873 uap->control_reg = uap->port.membase;
1874 uap->data_reg = uap->control_reg + 4;
1875 uap->port_type = 0;
1876
1877 pmz_convert_to_zs(uap, CS8, 0, 9600);
1878
1879 return 0;
1880}
1881
1882static int __init pmz_probe(void)
1883{
1884 int err;
1885
1886 pmz_ports_count = 0;
1887
1888 pmz_ports[0].mate = &pmz_ports[1];
1889 pmz_ports[0].port.line = 0;
1890 pmz_ports[0].flags = PMACZILOG_FLAG_IS_CHANNEL_A;
1891 pmz_ports[0].node = &scc_a_pdev;
1892 err = pmz_init_port(&pmz_ports[0]);
1893 if (err)
1894 return err;
1895 pmz_ports_count++;
1896
1897 pmz_ports[1].mate = &pmz_ports[0];
1898 pmz_ports[1].port.line = 1;
1899 pmz_ports[1].flags = 0;
1900 pmz_ports[1].node = &scc_b_pdev;
1901 err = pmz_init_port(&pmz_ports[1]);
1902 if (err)
1903 return err;
1904 pmz_ports_count++;
1905
1906 return 0;
1907}
1908
1909static void pmz_dispose_port(struct uart_pmac_port *uap)
1910{
1911 memset(uap, 0, sizeof(struct uart_pmac_port));
1912}
1913
1914static int __init pmz_attach(struct platform_device *pdev)
1915{
1916 int i;
1917
1918 for (i = 0; i < pmz_ports_count; i++)
1919 if (pmz_ports[i].node == pdev)
1920 return 0;
1921 return -ENODEV;
1922}
1923
1924static int __exit pmz_detach(struct platform_device *pdev)
1925{
1926 return 0;
1927}
1928
1929#endif /* !CONFIG_PPC_PMAC */
1930
1931#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1932
1933static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1934static int __init pmz_console_setup(struct console *co, char *options);
1935
1936static struct console pmz_console = {
1937 .name = PMACZILOG_NAME,
1938 .write = pmz_console_write,
1939 .device = uart_console_device,
1940 .setup = pmz_console_setup,
1941 .flags = CON_PRINTBUFFER,
1942 .index = -1,
1943 .data = &pmz_uart_reg,
1944};
1945
1946#define PMACZILOG_CONSOLE &pmz_console
1947#else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1948#define PMACZILOG_CONSOLE (NULL)
1949#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1950
1951/*
1952 * Register the driver, console driver and ports with the serial
1953 * core
1954 */
1955static int __init pmz_register(void)
1956{
1957 int i, rc;
1958
1959 pmz_uart_reg.nr = pmz_ports_count;
1960 pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1961
1962 /*
1963 * Register this driver with the serial core
1964 */
1965 rc = uart_register_driver(&pmz_uart_reg);
1966 if (rc)
1967 return rc;
1968
1969 /*
1970 * Register each port with the serial core
1971 */
1972 for (i = 0; i < pmz_ports_count; i++) {
1973 struct uart_pmac_port *uport = &pmz_ports[i];
1974 /* NULL node may happen on wallstreet */
1975 if (uport->node != NULL)
1976 rc = uart_add_one_port(&pmz_uart_reg, &uport->port);
1977 if (rc)
1978 goto err_out;
1979 }
1980
1981 retur…Large files files are truncated, but you can click here to view the full file