1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Driver for PowerMac Z85c30 based ESCC cell found in the
4 * "macio" ASICs of various PowerMac models
5 *
6 * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
7 *
8 * Derived from drivers/macintosh/macserial.c by Paul Mackerras
9 * and drivers/serial/sunzilog.c by David S. Miller
10 *
11 * Hrm... actually, I ripped most of sunzilog (Thanks David !) and
12 * adapted special tweaks needed for us. I don't think it's worth
13 * merging back those though. The DMA code still has to get in
14 * and once done, I expect that driver to remain fairly stable in
15 * the long term, unless we change the driver model again...
16 *
17 * 2004-08-06 Harald Welte <laforge@gnumonks.org>
18 * - Enable BREAK interrupt
19 * - Add support for sysreq
20 *
21 * TODO: - Add DMA support
22 * - Defer port shutdown to a few seconds after close
23 * - maybe put something right into uap->clk_divisor
24 */
25
26 #undef DEBUG
27 #undef USE_CTRL_O_SYSRQ
28
29 #include <linux/module.h>
30 #include <linux/tty.h>
31
32 #include <linux/tty_flip.h>
33 #include <linux/major.h>
34 #include <linux/string.h>
35 #include <linux/fcntl.h>
36 #include <linux/mm.h>
37 #include <linux/kernel.h>
38 #include <linux/delay.h>
39 #include <linux/init.h>
40 #include <linux/console.h>
41 #include <linux/adb.h>
42 #include <linux/pmu.h>
43 #include <linux/bitops.h>
44 #include <linux/sysrq.h>
45 #include <linux/mutex.h>
46 #include <linux/of_address.h>
47 #include <linux/of_irq.h>
48 #include <asm/sections.h>
49 #include <linux/io.h>
50 #include <asm/irq.h>
51
52 #ifdef CONFIG_PPC_PMAC
53 #include <asm/machdep.h>
54 #include <asm/pmac_feature.h>
55 #include <asm/macio.h>
56 #else
57 #include <linux/platform_device.h>
58 #define of_machine_is_compatible(x) (0)
59 #endif
60
61 #include <linux/serial.h>
62 #include <linux/serial_core.h>
63
64 #include "pmac_zilog.h"
65
66 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
67 MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
68 MODULE_LICENSE("GPL");
69
70 #ifdef CONFIG_SERIAL_PMACZILOG_TTYS
71 #define PMACZILOG_MAJOR TTY_MAJOR
72 #define PMACZILOG_MINOR 64
73 #define PMACZILOG_NAME "ttyS"
74 #else
75 #define PMACZILOG_MAJOR 204
76 #define PMACZILOG_MINOR 192
77 #define PMACZILOG_NAME "ttyPZ"
78 #endif
79
80 #define pmz_debug(fmt, arg...) pr_debug("ttyPZ%d: " fmt, uap->port.line, ## arg)
81 #define pmz_error(fmt, arg...) pr_err("ttyPZ%d: " fmt, uap->port.line, ## arg)
82 #define pmz_info(fmt, arg...) pr_info("ttyPZ%d: " fmt, uap->port.line, ## arg)
83
84 /*
85 * For the sake of early serial console, we can do a pre-probe
86 * (optional) of the ports at rather early boot time.
87 */
88 static struct uart_pmac_port pmz_ports[MAX_ZS_PORTS];
89 static int pmz_ports_count;
90
91 static struct uart_driver pmz_uart_reg = {
92 .owner = THIS_MODULE,
93 .driver_name = PMACZILOG_NAME,
94 .dev_name = PMACZILOG_NAME,
95 .major = PMACZILOG_MAJOR,
96 .minor = PMACZILOG_MINOR,
97 };
98
99
100 /*
101 * Load all registers to reprogram the port
102 * This function must only be called when the TX is not busy. The UART
103 * port lock must be held and local interrupts disabled.
104 */
pmz_load_zsregs(struct uart_pmac_port * uap,u8 * regs)105 static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
106 {
107 int i;
108
109 /* Let pending transmits finish. */
110 for (i = 0; i < 1000; i++) {
111 unsigned char stat = read_zsreg(uap, R1);
112 if (stat & ALL_SNT)
113 break;
114 udelay(100);
115 }
116
117 ZS_CLEARERR(uap);
118 zssync(uap);
119 ZS_CLEARFIFO(uap);
120 zssync(uap);
121 ZS_CLEARERR(uap);
122
123 /* Disable all interrupts. */
124 write_zsreg(uap, R1,
125 regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
126
127 /* Set parity, sync config, stop bits, and clock divisor. */
128 write_zsreg(uap, R4, regs[R4]);
129
130 /* Set misc. TX/RX control bits. */
131 write_zsreg(uap, R10, regs[R10]);
132
133 /* Set TX/RX controls sans the enable bits. */
134 write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
135 write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
136
137 /* now set R7 "prime" on ESCC */
138 write_zsreg(uap, R15, regs[R15] | EN85C30);
139 write_zsreg(uap, R7, regs[R7P]);
140
141 /* make sure we use R7 "non-prime" on ESCC */
142 write_zsreg(uap, R15, regs[R15] & ~EN85C30);
143
144 /* Synchronous mode config. */
145 write_zsreg(uap, R6, regs[R6]);
146 write_zsreg(uap, R7, regs[R7]);
147
148 /* Disable baud generator. */
149 write_zsreg(uap, R14, regs[R14] & ~BRENAB);
150
151 /* Clock mode control. */
152 write_zsreg(uap, R11, regs[R11]);
153
154 /* Lower and upper byte of baud rate generator divisor. */
155 write_zsreg(uap, R12, regs[R12]);
156 write_zsreg(uap, R13, regs[R13]);
157
158 /* Now rewrite R14, with BRENAB (if set). */
159 write_zsreg(uap, R14, regs[R14]);
160
161 /* Reset external status interrupts. */
162 write_zsreg(uap, R0, RES_EXT_INT);
163 write_zsreg(uap, R0, RES_EXT_INT);
164
165 /* Rewrite R3/R5, this time without enables masked. */
166 write_zsreg(uap, R3, regs[R3]);
167 write_zsreg(uap, R5, regs[R5]);
168
169 /* Rewrite R1, this time without IRQ enabled masked. */
170 write_zsreg(uap, R1, regs[R1]);
171
172 /* Enable interrupts */
173 write_zsreg(uap, R9, regs[R9]);
174 }
175
176 /*
177 * We do like sunzilog to avoid disrupting pending Tx
178 * Reprogram the Zilog channel HW registers with the copies found in the
179 * software state struct. If the transmitter is busy, we defer this update
180 * until the next TX complete interrupt. Else, we do it right now.
181 *
182 * The UART port lock must be held and local interrupts disabled.
183 */
pmz_maybe_update_regs(struct uart_pmac_port * uap)184 static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
185 {
186 if (!ZS_REGS_HELD(uap)) {
187 if (ZS_TX_ACTIVE(uap)) {
188 uap->flags |= PMACZILOG_FLAG_REGS_HELD;
189 } else {
190 pmz_debug("pmz: maybe_update_regs: updating\n");
191 pmz_load_zsregs(uap, uap->curregs);
192 }
193 }
194 }
195
pmz_interrupt_control(struct uart_pmac_port * uap,int enable)196 static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
197 {
198 if (enable) {
199 uap->curregs[1] |= INT_ALL_Rx | TxINT_ENAB;
200 if (!ZS_IS_EXTCLK(uap))
201 uap->curregs[1] |= EXT_INT_ENAB;
202 } else {
203 uap->curregs[1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
204 }
205 write_zsreg(uap, R1, uap->curregs[1]);
206 }
207
pmz_receive_chars(struct uart_pmac_port * uap)208 static bool pmz_receive_chars(struct uart_pmac_port *uap)
209 __must_hold(&uap->port.lock)
210 {
211 struct tty_port *port;
212 unsigned char ch, r1, drop, flag;
213
214 /* Sanity check, make sure the old bug is no longer happening */
215 if (uap->port.state == NULL) {
216 WARN_ON(1);
217 (void)read_zsdata(uap);
218 return false;
219 }
220 port = &uap->port.state->port;
221
222 while (1) {
223 drop = 0;
224
225 r1 = read_zsreg(uap, R1);
226 ch = read_zsdata(uap);
227
228 if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
229 write_zsreg(uap, R0, ERR_RES);
230 zssync(uap);
231 }
232
233 ch &= uap->parity_mask;
234 if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
235 uap->flags &= ~PMACZILOG_FLAG_BREAK;
236 }
237
238 #if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
239 #ifdef USE_CTRL_O_SYSRQ
240 /* Handle the SysRq ^O Hack */
241 if (ch == '\x0f') {
242 uap->port.sysrq = jiffies + HZ*5;
243 goto next_char;
244 }
245 #endif /* USE_CTRL_O_SYSRQ */
246 if (uap->port.sysrq) {
247 int swallow;
248 uart_port_unlock(&uap->port);
249 swallow = uart_handle_sysrq_char(&uap->port, ch);
250 uart_port_lock(&uap->port);
251 if (swallow)
252 goto next_char;
253 }
254 #endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
255
256 /* A real serial line, record the character and status. */
257 if (drop)
258 goto next_char;
259
260 flag = TTY_NORMAL;
261 uap->port.icount.rx++;
262
263 if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
264 if (r1 & BRK_ABRT) {
265 pmz_debug("pmz: got break !\n");
266 r1 &= ~(PAR_ERR | CRC_ERR);
267 uap->port.icount.brk++;
268 if (uart_handle_break(&uap->port))
269 goto next_char;
270 }
271 else if (r1 & PAR_ERR)
272 uap->port.icount.parity++;
273 else if (r1 & CRC_ERR)
274 uap->port.icount.frame++;
275 if (r1 & Rx_OVR)
276 uap->port.icount.overrun++;
277 r1 &= uap->port.read_status_mask;
278 if (r1 & BRK_ABRT)
279 flag = TTY_BREAK;
280 else if (r1 & PAR_ERR)
281 flag = TTY_PARITY;
282 else if (r1 & CRC_ERR)
283 flag = TTY_FRAME;
284 }
285
286 if (uap->port.ignore_status_mask == 0xff ||
287 (r1 & uap->port.ignore_status_mask) == 0) {
288 tty_insert_flip_char(port, ch, flag);
289 }
290 if (r1 & Rx_OVR)
291 tty_insert_flip_char(port, 0, TTY_OVERRUN);
292 next_char:
293 ch = read_zsreg(uap, R0);
294 if (!(ch & Rx_CH_AV))
295 break;
296 }
297
298 return true;
299 }
300
pmz_status_handle(struct uart_pmac_port * uap)301 static void pmz_status_handle(struct uart_pmac_port *uap)
302 {
303 unsigned char status;
304
305 status = read_zsreg(uap, R0);
306 write_zsreg(uap, R0, RES_EXT_INT);
307 zssync(uap);
308
309 if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
310 if (status & SYNC_HUNT)
311 uap->port.icount.dsr++;
312
313 /* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
314 * But it does not tell us which bit has changed, we have to keep
315 * track of this ourselves.
316 * The CTS input is inverted for some reason. -- paulus
317 */
318 if ((status ^ uap->prev_status) & DCD)
319 uart_handle_dcd_change(&uap->port,
320 (status & DCD));
321 if ((status ^ uap->prev_status) & CTS)
322 uart_handle_cts_change(&uap->port,
323 !(status & CTS));
324
325 wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
326 }
327
328 if (status & BRK_ABRT)
329 uap->flags |= PMACZILOG_FLAG_BREAK;
330
331 uap->prev_status = status;
332 }
333
pmz_transmit_chars(struct uart_pmac_port * uap)334 static void pmz_transmit_chars(struct uart_pmac_port *uap)
335 {
336 struct tty_port *tport;
337 unsigned char ch;
338
339 if (ZS_IS_CONS(uap)) {
340 unsigned char status = read_zsreg(uap, R0);
341
342 /* TX still busy? Just wait for the next TX done interrupt.
343 *
344 * It can occur because of how we do serial console writes. It would
345 * be nice to transmit console writes just like we normally would for
346 * a TTY line. (ie. buffered and TX interrupt driven). That is not
347 * easy because console writes cannot sleep. One solution might be
348 * to poll on enough port->xmit space becoming free. -DaveM
349 */
350 if (!(status & Tx_BUF_EMP))
351 return;
352 }
353
354 uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
355
356 if (ZS_REGS_HELD(uap)) {
357 pmz_load_zsregs(uap, uap->curregs);
358 uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
359 }
360
361 if (ZS_TX_STOPPED(uap)) {
362 uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
363 goto ack_tx_int;
364 }
365
366 /* Under some circumstances, we see interrupts reported for
367 * a closed channel. The interrupt mask in R1 is clear, but
368 * R3 still signals the interrupts and we see them when taking
369 * an interrupt for the other channel (this could be a qemu
370 * bug but since the ESCC doc doesn't specify precsiely whether
371 * R3 interrup status bits are masked by R1 interrupt enable
372 * bits, better safe than sorry). --BenH.
373 */
374 if (!ZS_IS_OPEN(uap))
375 goto ack_tx_int;
376
377 if (uap->port.x_char) {
378 uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
379 write_zsdata(uap, uap->port.x_char);
380 zssync(uap);
381 uap->port.icount.tx++;
382 uap->port.x_char = 0;
383 return;
384 }
385
386 if (uap->port.state == NULL)
387 goto ack_tx_int;
388 tport = &uap->port.state->port;
389 if (kfifo_is_empty(&tport->xmit_fifo)) {
390 uart_write_wakeup(&uap->port);
391 goto ack_tx_int;
392 }
393 if (uart_tx_stopped(&uap->port))
394 goto ack_tx_int;
395
396 uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
397 WARN_ON(!uart_fifo_get(&uap->port, &ch));
398 write_zsdata(uap, ch);
399 zssync(uap);
400
401 if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
402 uart_write_wakeup(&uap->port);
403
404 return;
405
406 ack_tx_int:
407 write_zsreg(uap, R0, RES_Tx_P);
408 zssync(uap);
409 }
410
411 /* Hrm... we register that twice, fixme later.... */
pmz_interrupt(int irq,void * dev_id)412 static irqreturn_t pmz_interrupt(int irq, void *dev_id)
413 {
414 struct uart_pmac_port *uap = dev_id;
415 struct uart_pmac_port *uap_a;
416 struct uart_pmac_port *uap_b;
417 int rc = IRQ_NONE;
418 bool push;
419 u8 r3;
420
421 uap_a = pmz_get_port_A(uap);
422 uap_b = uap_a->mate;
423
424 uart_port_lock(&uap_a->port);
425 r3 = read_zsreg(uap_a, R3);
426
427 /* Channel A */
428 push = false;
429 if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
430 if (!ZS_IS_OPEN(uap_a)) {
431 pmz_debug("ChanA interrupt while not open !\n");
432 goto skip_a;
433 }
434 write_zsreg(uap_a, R0, RES_H_IUS);
435 zssync(uap_a);
436 if (r3 & CHAEXT)
437 pmz_status_handle(uap_a);
438 if (r3 & CHARxIP)
439 push = pmz_receive_chars(uap_a);
440 if (r3 & CHATxIP)
441 pmz_transmit_chars(uap_a);
442 rc = IRQ_HANDLED;
443 }
444 skip_a:
445 uart_port_unlock(&uap_a->port);
446 if (push)
447 tty_flip_buffer_push(&uap->port.state->port);
448
449 if (!uap_b)
450 goto out;
451
452 uart_port_lock(&uap_b->port);
453 push = false;
454 if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
455 if (!ZS_IS_OPEN(uap_b)) {
456 pmz_debug("ChanB interrupt while not open !\n");
457 goto skip_b;
458 }
459 write_zsreg(uap_b, R0, RES_H_IUS);
460 zssync(uap_b);
461 if (r3 & CHBEXT)
462 pmz_status_handle(uap_b);
463 if (r3 & CHBRxIP)
464 push = pmz_receive_chars(uap_b);
465 if (r3 & CHBTxIP)
466 pmz_transmit_chars(uap_b);
467 rc = IRQ_HANDLED;
468 }
469 skip_b:
470 uart_port_unlock(&uap_b->port);
471 if (push)
472 tty_flip_buffer_push(&uap->port.state->port);
473
474 out:
475 return rc;
476 }
477
478 /*
479 * Peek the status register, lock not held by caller
480 */
pmz_peek_status(struct uart_pmac_port * uap)481 static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
482 {
483 unsigned long flags;
484 u8 status;
485
486 uart_port_lock_irqsave(&uap->port, &flags);
487 status = read_zsreg(uap, R0);
488 uart_port_unlock_irqrestore(&uap->port, flags);
489
490 return status;
491 }
492
493 /*
494 * Check if transmitter is empty
495 * The port lock is not held.
496 */
pmz_tx_empty(struct uart_port * port)497 static unsigned int pmz_tx_empty(struct uart_port *port)
498 {
499 unsigned char status;
500
501 status = pmz_peek_status(to_pmz(port));
502 if (status & Tx_BUF_EMP)
503 return TIOCSER_TEMT;
504 return 0;
505 }
506
507 /*
508 * Set Modem Control (RTS & DTR) bits
509 * The port lock is held and interrupts are disabled.
510 * Note: Shall we really filter out RTS on external ports or
511 * should that be dealt at higher level only ?
512 */
pmz_set_mctrl(struct uart_port * port,unsigned int mctrl)513 static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
514 {
515 struct uart_pmac_port *uap = to_pmz(port);
516 unsigned char set_bits, clear_bits;
517
518 /* Do nothing for irda for now... */
519 if (ZS_IS_IRDA(uap))
520 return;
521 /* We get called during boot with a port not up yet */
522 if (!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
523 return;
524
525 set_bits = clear_bits = 0;
526
527 if (ZS_IS_INTMODEM(uap)) {
528 if (mctrl & TIOCM_RTS)
529 set_bits |= RTS;
530 else
531 clear_bits |= RTS;
532 }
533 if (mctrl & TIOCM_DTR)
534 set_bits |= DTR;
535 else
536 clear_bits |= DTR;
537
538 /* NOTE: Not subject to 'transmitter active' rule. */
539 uap->curregs[R5] |= set_bits;
540 uap->curregs[R5] &= ~clear_bits;
541
542 write_zsreg(uap, R5, uap->curregs[R5]);
543 pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
544 set_bits, clear_bits, uap->curregs[R5]);
545 zssync(uap);
546 }
547
548 /*
549 * Get Modem Control bits (only the input ones, the core will
550 * or that with a cached value of the control ones)
551 * The port lock is held and interrupts are disabled.
552 */
pmz_get_mctrl(struct uart_port * port)553 static unsigned int pmz_get_mctrl(struct uart_port *port)
554 {
555 struct uart_pmac_port *uap = to_pmz(port);
556 unsigned char status;
557 unsigned int ret;
558
559 status = read_zsreg(uap, R0);
560
561 ret = 0;
562 if (status & DCD)
563 ret |= TIOCM_CAR;
564 if (status & SYNC_HUNT)
565 ret |= TIOCM_DSR;
566 if (!(status & CTS))
567 ret |= TIOCM_CTS;
568
569 return ret;
570 }
571
572 /*
573 * Stop TX side. Dealt like sunzilog at next Tx interrupt,
574 * though for DMA, we will have to do a bit more.
575 * The port lock is held and interrupts are disabled.
576 */
pmz_stop_tx(struct uart_port * port)577 static void pmz_stop_tx(struct uart_port *port)
578 {
579 to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
580 }
581
582 /*
583 * Kick the Tx side.
584 * The port lock is held and interrupts are disabled.
585 */
pmz_start_tx(struct uart_port * port)586 static void pmz_start_tx(struct uart_port *port)
587 {
588 struct uart_pmac_port *uap = to_pmz(port);
589 unsigned char status;
590
591 uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
592 uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
593
594 status = read_zsreg(uap, R0);
595
596 /* TX busy? Just wait for the TX done interrupt. */
597 if (!(status & Tx_BUF_EMP))
598 return;
599
600 /* Send the first character to jump-start the TX done
601 * IRQ sending engine.
602 */
603 if (port->x_char) {
604 write_zsdata(uap, port->x_char);
605 zssync(uap);
606 port->icount.tx++;
607 port->x_char = 0;
608 } else {
609 struct tty_port *tport = &port->state->port;
610 unsigned char ch;
611
612 if (!uart_fifo_get(&uap->port, &ch))
613 return;
614 write_zsdata(uap, ch);
615 zssync(uap);
616
617 if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
618 uart_write_wakeup(&uap->port);
619 }
620 }
621
622 /*
623 * Stop Rx side, basically disable emitting of
624 * Rx interrupts on the port. We don't disable the rx
625 * side of the chip proper though
626 * The port lock is held.
627 */
pmz_stop_rx(struct uart_port * port)628 static void pmz_stop_rx(struct uart_port *port)
629 {
630 struct uart_pmac_port *uap = to_pmz(port);
631
632 /* Disable all RX interrupts. */
633 uap->curregs[R1] &= ~RxINT_MASK;
634 pmz_maybe_update_regs(uap);
635 }
636
637 /*
638 * Enable modem status change interrupts
639 * The port lock is held.
640 */
pmz_enable_ms(struct uart_port * port)641 static void pmz_enable_ms(struct uart_port *port)
642 {
643 struct uart_pmac_port *uap = to_pmz(port);
644 unsigned char new_reg;
645
646 if (ZS_IS_IRDA(uap))
647 return;
648 new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
649 if (new_reg != uap->curregs[R15]) {
650 uap->curregs[R15] = new_reg;
651
652 /* NOTE: Not subject to 'transmitter active' rule. */
653 write_zsreg(uap, R15, uap->curregs[R15]);
654 }
655 }
656
657 /*
658 * Control break state emission
659 * The port lock is not held.
660 */
pmz_break_ctl(struct uart_port * port,int break_state)661 static void pmz_break_ctl(struct uart_port *port, int break_state)
662 {
663 struct uart_pmac_port *uap = to_pmz(port);
664 unsigned char set_bits, clear_bits, new_reg;
665 unsigned long flags;
666
667 set_bits = clear_bits = 0;
668
669 if (break_state)
670 set_bits |= SND_BRK;
671 else
672 clear_bits |= SND_BRK;
673
674 uart_port_lock_irqsave(port, &flags);
675
676 new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
677 if (new_reg != uap->curregs[R5]) {
678 uap->curregs[R5] = new_reg;
679 write_zsreg(uap, R5, uap->curregs[R5]);
680 }
681
682 uart_port_unlock_irqrestore(port, flags);
683 }
684
685 #ifdef CONFIG_PPC_PMAC
686
687 /*
688 * Turn power on or off to the SCC and associated stuff
689 * (port drivers, modem, IR port, etc.)
690 * Returns the number of milliseconds we should wait before
691 * trying to use the port.
692 */
pmz_set_scc_power(struct uart_pmac_port * uap,int state)693 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
694 {
695 int delay = 0;
696 int rc;
697
698 if (state) {
699 rc = pmac_call_feature(
700 PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
701 pmz_debug("port power on result: %d\n", rc);
702 if (ZS_IS_INTMODEM(uap)) {
703 rc = pmac_call_feature(
704 PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
705 delay = 2500; /* wait for 2.5s before using */
706 pmz_debug("modem power result: %d\n", rc);
707 }
708 } else {
709 /* TODO: Make that depend on a timer, don't power down
710 * immediately
711 */
712 if (ZS_IS_INTMODEM(uap)) {
713 rc = pmac_call_feature(
714 PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
715 pmz_debug("port power off result: %d\n", rc);
716 }
717 pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
718 }
719 return delay;
720 }
721
722 #else
723
pmz_set_scc_power(struct uart_pmac_port * uap,int state)724 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
725 {
726 return 0;
727 }
728
729 #endif /* !CONFIG_PPC_PMAC */
730
731 /*
732 * FixZeroBug....Works around a bug in the SCC receiving channel.
733 * Inspired from Darwin code, 15 Sept. 2000 -DanM
734 *
735 * The following sequence prevents a problem that is seen with O'Hare ASICs
736 * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
737 * at the input to the receiver becomes 'stuck' and locks up the receiver.
738 * This problem can occur as a result of a zero bit at the receiver input
739 * coincident with any of the following events:
740 *
741 * The SCC is initialized (hardware or software).
742 * A framing error is detected.
743 * The clocking option changes from synchronous or X1 asynchronous
744 * clocking to X16, X32, or X64 asynchronous clocking.
745 * The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
746 *
747 * This workaround attempts to recover from the lockup condition by placing
748 * the SCC in synchronous loopback mode with a fast clock before programming
749 * any of the asynchronous modes.
750 */
pmz_fix_zero_bug_scc(struct uart_pmac_port * uap)751 static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
752 {
753 write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
754 zssync(uap);
755 udelay(10);
756 write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
757 zssync(uap);
758
759 write_zsreg(uap, 4, X1CLK | MONSYNC);
760 write_zsreg(uap, 3, Rx8);
761 write_zsreg(uap, 5, Tx8 | RTS);
762 write_zsreg(uap, 9, NV); /* Didn't we already do this? */
763 write_zsreg(uap, 11, RCBR | TCBR);
764 write_zsreg(uap, 12, 0);
765 write_zsreg(uap, 13, 0);
766 write_zsreg(uap, 14, (LOOPBAK | BRSRC));
767 write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
768 write_zsreg(uap, 3, Rx8 | RxENABLE);
769 write_zsreg(uap, 0, RES_EXT_INT);
770 write_zsreg(uap, 0, RES_EXT_INT);
771 write_zsreg(uap, 0, RES_EXT_INT); /* to kill some time */
772
773 /* The channel should be OK now, but it is probably receiving
774 * loopback garbage.
775 * Switch to asynchronous mode, disable the receiver,
776 * and discard everything in the receive buffer.
777 */
778 write_zsreg(uap, 9, NV);
779 write_zsreg(uap, 4, X16CLK | SB_MASK);
780 write_zsreg(uap, 3, Rx8);
781
782 while (read_zsreg(uap, 0) & Rx_CH_AV) {
783 (void)read_zsreg(uap, 8);
784 write_zsreg(uap, 0, RES_EXT_INT);
785 write_zsreg(uap, 0, ERR_RES);
786 }
787 }
788
789 /*
790 * Real startup routine, powers up the hardware and sets up
791 * the SCC. Returns a delay in ms where you need to wait before
792 * actually using the port, this is typically the internal modem
793 * powerup delay. This routine expect the lock to be taken.
794 */
__pmz_startup(struct uart_pmac_port * uap)795 static int __pmz_startup(struct uart_pmac_port *uap)
796 {
797 int pwr_delay = 0;
798
799 memset(&uap->curregs, 0, sizeof(uap->curregs));
800
801 /* Power up the SCC & underlying hardware (modem/irda) */
802 pwr_delay = pmz_set_scc_power(uap, 1);
803
804 /* Nice buggy HW ... */
805 pmz_fix_zero_bug_scc(uap);
806
807 /* Reset the channel */
808 uap->curregs[R9] = 0;
809 write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
810 zssync(uap);
811 udelay(10);
812 write_zsreg(uap, 9, 0);
813 zssync(uap);
814
815 /* Clear the interrupt registers */
816 write_zsreg(uap, R1, 0);
817 write_zsreg(uap, R0, ERR_RES);
818 write_zsreg(uap, R0, ERR_RES);
819 write_zsreg(uap, R0, RES_H_IUS);
820 write_zsreg(uap, R0, RES_H_IUS);
821
822 /* Setup some valid baud rate */
823 uap->curregs[R4] = X16CLK | SB1;
824 uap->curregs[R3] = Rx8;
825 uap->curregs[R5] = Tx8 | RTS;
826 if (!ZS_IS_IRDA(uap))
827 uap->curregs[R5] |= DTR;
828 uap->curregs[R12] = 0;
829 uap->curregs[R13] = 0;
830 uap->curregs[R14] = BRENAB;
831
832 /* Clear handshaking, enable BREAK interrupts */
833 uap->curregs[R15] = BRKIE;
834
835 /* Master interrupt enable */
836 uap->curregs[R9] |= NV | MIE;
837
838 pmz_load_zsregs(uap, uap->curregs);
839
840 /* Enable receiver and transmitter. */
841 write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
842 write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
843
844 /* Remember status for DCD/CTS changes */
845 uap->prev_status = read_zsreg(uap, R0);
846
847 return pwr_delay;
848 }
849
pmz_irda_reset(struct uart_pmac_port * uap)850 static void pmz_irda_reset(struct uart_pmac_port *uap)
851 {
852 unsigned long flags;
853
854 uart_port_lock_irqsave(&uap->port, &flags);
855 uap->curregs[R5] |= DTR;
856 write_zsreg(uap, R5, uap->curregs[R5]);
857 zssync(uap);
858 uart_port_unlock_irqrestore(&uap->port, flags);
859 msleep(110);
860
861 uart_port_lock_irqsave(&uap->port, &flags);
862 uap->curregs[R5] &= ~DTR;
863 write_zsreg(uap, R5, uap->curregs[R5]);
864 zssync(uap);
865 uart_port_unlock_irqrestore(&uap->port, flags);
866 msleep(10);
867 }
868
869 /*
870 * This is the "normal" startup routine, using the above one
871 * wrapped with the lock and doing a schedule delay
872 */
pmz_startup(struct uart_port * port)873 static int pmz_startup(struct uart_port *port)
874 {
875 struct uart_pmac_port *uap = to_pmz(port);
876 unsigned long flags;
877 int pwr_delay = 0;
878
879 uap->flags |= PMACZILOG_FLAG_IS_OPEN;
880
881 /* A console is never powered down. Else, power up and
882 * initialize the chip
883 */
884 if (!ZS_IS_CONS(uap)) {
885 uart_port_lock_irqsave(port, &flags);
886 pwr_delay = __pmz_startup(uap);
887 uart_port_unlock_irqrestore(port, flags);
888 }
889 sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line);
890 if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
891 uap->irq_name, uap)) {
892 pmz_error("Unable to register zs interrupt handler.\n");
893 pmz_set_scc_power(uap, 0);
894 return -ENXIO;
895 }
896
897 /* Right now, we deal with delay by blocking here, I'll be
898 * smarter later on
899 */
900 if (pwr_delay != 0) {
901 pmz_debug("pmz: delaying %d ms\n", pwr_delay);
902 msleep(pwr_delay);
903 }
904
905 /* IrDA reset is done now */
906 if (ZS_IS_IRDA(uap))
907 pmz_irda_reset(uap);
908
909 /* Enable interrupt requests for the channel */
910 uart_port_lock_irqsave(port, &flags);
911 pmz_interrupt_control(uap, 1);
912 uart_port_unlock_irqrestore(port, flags);
913
914 return 0;
915 }
916
pmz_shutdown(struct uart_port * port)917 static void pmz_shutdown(struct uart_port *port)
918 {
919 struct uart_pmac_port *uap = to_pmz(port);
920 unsigned long flags;
921
922 uart_port_lock_irqsave(port, &flags);
923
924 /* Disable interrupt requests for the channel */
925 pmz_interrupt_control(uap, 0);
926
927 if (!ZS_IS_CONS(uap)) {
928 /* Disable receiver and transmitter */
929 uap->curregs[R3] &= ~RxENABLE;
930 uap->curregs[R5] &= ~TxENABLE;
931
932 /* Disable break assertion */
933 uap->curregs[R5] &= ~SND_BRK;
934 pmz_maybe_update_regs(uap);
935 }
936
937 uart_port_unlock_irqrestore(port, flags);
938
939 /* Release interrupt handler */
940 free_irq(uap->port.irq, uap);
941
942 uart_port_lock_irqsave(port, &flags);
943
944 uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
945
946 if (!ZS_IS_CONS(uap))
947 pmz_set_scc_power(uap, 0); /* Shut the chip down */
948
949 uart_port_unlock_irqrestore(port, flags);
950 }
951
952 /* Shared by TTY driver and serial console setup. The port lock is held
953 * and local interrupts are disabled.
954 */
pmz_convert_to_zs(struct uart_pmac_port * uap,unsigned int cflag,unsigned int iflag,unsigned long baud)955 static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
956 unsigned int iflag, unsigned long baud)
957 {
958 int brg;
959
960 /* Switch to external clocking for IrDA high clock rates. That
961 * code could be re-used for Midi interfaces with different
962 * multipliers
963 */
964 if (baud >= 115200 && ZS_IS_IRDA(uap)) {
965 uap->curregs[R4] = X1CLK;
966 uap->curregs[R11] = RCTRxCP | TCTRxCP;
967 uap->curregs[R14] = 0; /* BRG off */
968 uap->curregs[R12] = 0;
969 uap->curregs[R13] = 0;
970 uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
971 } else {
972 switch (baud) {
973 case ZS_CLOCK/16: /* 230400 */
974 uap->curregs[R4] = X16CLK;
975 uap->curregs[R11] = 0;
976 uap->curregs[R14] = 0;
977 break;
978 case ZS_CLOCK/32: /* 115200 */
979 uap->curregs[R4] = X32CLK;
980 uap->curregs[R11] = 0;
981 uap->curregs[R14] = 0;
982 break;
983 default:
984 uap->curregs[R4] = X16CLK;
985 uap->curregs[R11] = TCBR | RCBR;
986 brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
987 uap->curregs[R12] = (brg & 255);
988 uap->curregs[R13] = ((brg >> 8) & 255);
989 uap->curregs[R14] = BRENAB;
990 }
991 uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
992 }
993
994 /* Character size, stop bits, and parity. */
995 uap->curregs[3] &= ~RxN_MASK;
996 uap->curregs[5] &= ~TxN_MASK;
997
998 switch (cflag & CSIZE) {
999 case CS5:
1000 uap->curregs[3] |= Rx5;
1001 uap->curregs[5] |= Tx5;
1002 uap->parity_mask = 0x1f;
1003 break;
1004 case CS6:
1005 uap->curregs[3] |= Rx6;
1006 uap->curregs[5] |= Tx6;
1007 uap->parity_mask = 0x3f;
1008 break;
1009 case CS7:
1010 uap->curregs[3] |= Rx7;
1011 uap->curregs[5] |= Tx7;
1012 uap->parity_mask = 0x7f;
1013 break;
1014 case CS8:
1015 default:
1016 uap->curregs[3] |= Rx8;
1017 uap->curregs[5] |= Tx8;
1018 uap->parity_mask = 0xff;
1019 break;
1020 }
1021 uap->curregs[4] &= ~(SB_MASK);
1022 if (cflag & CSTOPB)
1023 uap->curregs[4] |= SB2;
1024 else
1025 uap->curregs[4] |= SB1;
1026 if (cflag & PARENB)
1027 uap->curregs[4] |= PAR_ENAB;
1028 else
1029 uap->curregs[4] &= ~PAR_ENAB;
1030 if (!(cflag & PARODD))
1031 uap->curregs[4] |= PAR_EVEN;
1032 else
1033 uap->curregs[4] &= ~PAR_EVEN;
1034
1035 uap->port.read_status_mask = Rx_OVR;
1036 if (iflag & INPCK)
1037 uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1038 if (iflag & (IGNBRK | BRKINT | PARMRK))
1039 uap->port.read_status_mask |= BRK_ABRT;
1040
1041 uap->port.ignore_status_mask = 0;
1042 if (iflag & IGNPAR)
1043 uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1044 if (iflag & IGNBRK) {
1045 uap->port.ignore_status_mask |= BRK_ABRT;
1046 if (iflag & IGNPAR)
1047 uap->port.ignore_status_mask |= Rx_OVR;
1048 }
1049
1050 if ((cflag & CREAD) == 0)
1051 uap->port.ignore_status_mask = 0xff;
1052 }
1053
1054
1055 /*
1056 * Set the irda codec on the imac to the specified baud rate.
1057 */
pmz_irda_setup(struct uart_pmac_port * uap,unsigned long * baud)1058 static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1059 {
1060 u8 cmdbyte;
1061 int t, version;
1062
1063 switch (*baud) {
1064 /* SIR modes */
1065 case 2400:
1066 cmdbyte = 0x53;
1067 break;
1068 case 4800:
1069 cmdbyte = 0x52;
1070 break;
1071 case 9600:
1072 cmdbyte = 0x51;
1073 break;
1074 case 19200:
1075 cmdbyte = 0x50;
1076 break;
1077 case 38400:
1078 cmdbyte = 0x4f;
1079 break;
1080 case 57600:
1081 cmdbyte = 0x4e;
1082 break;
1083 case 115200:
1084 cmdbyte = 0x4d;
1085 break;
1086 /* The FIR modes aren't really supported at this point, how
1087 * do we select the speed ? via the FCR on KeyLargo ?
1088 */
1089 case 1152000:
1090 cmdbyte = 0;
1091 break;
1092 case 4000000:
1093 cmdbyte = 0;
1094 break;
1095 default: /* 9600 */
1096 cmdbyte = 0x51;
1097 *baud = 9600;
1098 break;
1099 }
1100
1101 /* Wait for transmitter to drain */
1102 t = 10000;
1103 while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1104 || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1105 if (--t <= 0) {
1106 pmz_error("transmitter didn't drain\n");
1107 return;
1108 }
1109 udelay(10);
1110 }
1111
1112 /* Drain the receiver too */
1113 t = 100;
1114 (void)read_zsdata(uap);
1115 (void)read_zsdata(uap);
1116 (void)read_zsdata(uap);
1117 mdelay(10);
1118 while (read_zsreg(uap, R0) & Rx_CH_AV) {
1119 read_zsdata(uap);
1120 mdelay(10);
1121 if (--t <= 0) {
1122 pmz_error("receiver didn't drain\n");
1123 return;
1124 }
1125 }
1126
1127 /* Switch to command mode */
1128 uap->curregs[R5] |= DTR;
1129 write_zsreg(uap, R5, uap->curregs[R5]);
1130 zssync(uap);
1131 mdelay(1);
1132
1133 /* Switch SCC to 19200 */
1134 pmz_convert_to_zs(uap, CS8, 0, 19200);
1135 pmz_load_zsregs(uap, uap->curregs);
1136 mdelay(1);
1137
1138 /* Write get_version command byte */
1139 write_zsdata(uap, 1);
1140 t = 5000;
1141 while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1142 if (--t <= 0) {
1143 pmz_error("irda_setup timed out on get_version byte\n");
1144 goto out;
1145 }
1146 udelay(10);
1147 }
1148 version = read_zsdata(uap);
1149
1150 if (version < 4) {
1151 pmz_info("IrDA: dongle version %d not supported\n", version);
1152 goto out;
1153 }
1154
1155 /* Send speed mode */
1156 write_zsdata(uap, cmdbyte);
1157 t = 5000;
1158 while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1159 if (--t <= 0) {
1160 pmz_error("irda_setup timed out on speed mode byte\n");
1161 goto out;
1162 }
1163 udelay(10);
1164 }
1165 t = read_zsdata(uap);
1166 if (t != cmdbyte)
1167 pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1168
1169 pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1170 *baud, version);
1171
1172 (void)read_zsdata(uap);
1173 (void)read_zsdata(uap);
1174 (void)read_zsdata(uap);
1175
1176 out:
1177 /* Switch back to data mode */
1178 uap->curregs[R5] &= ~DTR;
1179 write_zsreg(uap, R5, uap->curregs[R5]);
1180 zssync(uap);
1181
1182 (void)read_zsdata(uap);
1183 (void)read_zsdata(uap);
1184 (void)read_zsdata(uap);
1185 }
1186
1187
__pmz_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)1188 static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1189 const struct ktermios *old)
1190 {
1191 struct uart_pmac_port *uap = to_pmz(port);
1192 unsigned long baud;
1193
1194 /* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1195 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1196 * about the FIR mode and high speed modes. So these are unused. For
1197 * implementing proper support for these, we should probably add some
1198 * DMA as well, at least on the Rx side, which isn't a simple thing
1199 * at this point.
1200 */
1201 if (ZS_IS_IRDA(uap)) {
1202 /* Calc baud rate */
1203 baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1204 pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1205 /* Cet the irda codec to the right rate */
1206 pmz_irda_setup(uap, &baud);
1207 /* Set final baud rate */
1208 pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1209 pmz_load_zsregs(uap, uap->curregs);
1210 zssync(uap);
1211 } else {
1212 baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1213 pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1214 /* Make sure modem status interrupts are correctly configured */
1215 if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1216 uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1217 uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1218 } else {
1219 uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1220 uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1221 }
1222
1223 /* Load registers to the chip */
1224 pmz_maybe_update_regs(uap);
1225 }
1226 uart_update_timeout(port, termios->c_cflag, baud);
1227 }
1228
1229 /* The port lock is not held. */
pmz_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)1230 static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1231 const struct ktermios *old)
1232 {
1233 struct uart_pmac_port *uap = to_pmz(port);
1234 unsigned long flags;
1235
1236 uart_port_lock_irqsave(port, &flags);
1237
1238 /* Disable IRQs on the port */
1239 pmz_interrupt_control(uap, 0);
1240
1241 /* Setup new port configuration */
1242 __pmz_set_termios(port, termios, old);
1243
1244 /* Re-enable IRQs on the port */
1245 if (ZS_IS_OPEN(uap))
1246 pmz_interrupt_control(uap, 1);
1247
1248 uart_port_unlock_irqrestore(port, flags);
1249 }
1250
pmz_type(struct uart_port * port)1251 static const char *pmz_type(struct uart_port *port)
1252 {
1253 struct uart_pmac_port *uap = to_pmz(port);
1254
1255 if (ZS_IS_IRDA(uap))
1256 return "Z85c30 ESCC - Infrared port";
1257 else if (ZS_IS_INTMODEM(uap))
1258 return "Z85c30 ESCC - Internal modem";
1259 return "Z85c30 ESCC - Serial port";
1260 }
1261
1262 /* We do not request/release mappings of the registers here, this
1263 * happens at early serial probe time.
1264 */
pmz_release_port(struct uart_port * port)1265 static void pmz_release_port(struct uart_port *port)
1266 {
1267 }
1268
pmz_request_port(struct uart_port * port)1269 static int pmz_request_port(struct uart_port *port)
1270 {
1271 return 0;
1272 }
1273
1274 /* These do not need to do anything interesting either. */
pmz_config_port(struct uart_port * port,int flags)1275 static void pmz_config_port(struct uart_port *port, int flags)
1276 {
1277 }
1278
1279 /* We do not support letting the user mess with the divisor, IRQ, etc. */
pmz_verify_port(struct uart_port * port,struct serial_struct * ser)1280 static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1281 {
1282 return -EINVAL;
1283 }
1284
1285 #ifdef CONFIG_CONSOLE_POLL
1286
pmz_poll_get_char(struct uart_port * port)1287 static int pmz_poll_get_char(struct uart_port *port)
1288 {
1289 struct uart_pmac_port *uap =
1290 container_of(port, struct uart_pmac_port, port);
1291 int tries = 2;
1292
1293 while (tries) {
1294 if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)
1295 return read_zsdata(uap);
1296 if (tries--)
1297 udelay(5);
1298 }
1299
1300 return NO_POLL_CHAR;
1301 }
1302
pmz_poll_put_char(struct uart_port * port,unsigned char c)1303 static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1304 {
1305 struct uart_pmac_port *uap =
1306 container_of(port, struct uart_pmac_port, port);
1307
1308 /* Wait for the transmit buffer to empty. */
1309 while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1310 udelay(5);
1311 write_zsdata(uap, c);
1312 }
1313
1314 #endif /* CONFIG_CONSOLE_POLL */
1315
1316 static const struct uart_ops pmz_pops = {
1317 .tx_empty = pmz_tx_empty,
1318 .set_mctrl = pmz_set_mctrl,
1319 .get_mctrl = pmz_get_mctrl,
1320 .stop_tx = pmz_stop_tx,
1321 .start_tx = pmz_start_tx,
1322 .stop_rx = pmz_stop_rx,
1323 .enable_ms = pmz_enable_ms,
1324 .break_ctl = pmz_break_ctl,
1325 .startup = pmz_startup,
1326 .shutdown = pmz_shutdown,
1327 .set_termios = pmz_set_termios,
1328 .type = pmz_type,
1329 .release_port = pmz_release_port,
1330 .request_port = pmz_request_port,
1331 .config_port = pmz_config_port,
1332 .verify_port = pmz_verify_port,
1333 #ifdef CONFIG_CONSOLE_POLL
1334 .poll_get_char = pmz_poll_get_char,
1335 .poll_put_char = pmz_poll_put_char,
1336 #endif
1337 };
1338
1339 #ifdef CONFIG_PPC_PMAC
1340
1341 /*
1342 * Setup one port structure after probing, HW is down at this point,
1343 * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1344 * register our console before uart_add_one_port() is called
1345 */
pmz_init_port(struct uart_pmac_port * uap)1346 static int __init pmz_init_port(struct uart_pmac_port *uap)
1347 {
1348 struct device_node *np = uap->node;
1349 const char *conn;
1350 const struct slot_names_prop {
1351 int count;
1352 char name[1];
1353 } *slots;
1354 int len;
1355 struct resource r_ports;
1356
1357 /*
1358 * Request & map chip registers
1359 */
1360 if (of_address_to_resource(np, 0, &r_ports))
1361 return -ENODEV;
1362 uap->port.mapbase = r_ports.start;
1363 uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1364
1365 uap->control_reg = uap->port.membase;
1366 uap->data_reg = uap->control_reg + 0x10;
1367
1368 /*
1369 * Detect port type
1370 */
1371 if (of_device_is_compatible(np, "cobalt"))
1372 uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1373 conn = of_get_property(np, "AAPL,connector", &len);
1374 if (conn && (strcmp(conn, "infrared") == 0))
1375 uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1376 uap->port_type = PMAC_SCC_ASYNC;
1377 /* 1999 Powerbook G3 has slot-names property instead */
1378 slots = of_get_property(np, "slot-names", &len);
1379 if (slots && slots->count > 0) {
1380 if (strcmp(slots->name, "IrDA") == 0)
1381 uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1382 else if (strcmp(slots->name, "Modem") == 0)
1383 uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1384 }
1385 if (ZS_IS_IRDA(uap))
1386 uap->port_type = PMAC_SCC_IRDA;
1387 if (ZS_IS_INTMODEM(uap)) {
1388 struct device_node* i2c_modem =
1389 of_find_node_by_name(NULL, "i2c-modem");
1390 if (i2c_modem) {
1391 const char* mid =
1392 of_get_property(i2c_modem, "modem-id", NULL);
1393 if (mid) switch(*mid) {
1394 case 0x04 :
1395 case 0x05 :
1396 case 0x07 :
1397 case 0x08 :
1398 case 0x0b :
1399 case 0x0c :
1400 uap->port_type = PMAC_SCC_I2S1;
1401 }
1402 printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1403 mid ? (*mid) : 0);
1404 of_node_put(i2c_modem);
1405 } else {
1406 printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1407 }
1408 }
1409
1410 /*
1411 * Init remaining bits of "port" structure
1412 */
1413 uap->port.iotype = UPIO_MEM;
1414 uap->port.irq = irq_of_parse_and_map(np, 0);
1415 uap->port.uartclk = ZS_CLOCK;
1416 uap->port.fifosize = 1;
1417 uap->port.ops = &pmz_pops;
1418 uap->port.type = PORT_PMAC_ZILOG;
1419 uap->port.flags = 0;
1420
1421 /*
1422 * Fixup for the port on Gatwick for which the device-tree has
1423 * missing interrupts. Normally, the macio_dev would contain
1424 * fixed up interrupt info, but we use the device-tree directly
1425 * here due to early probing so we need the fixup too.
1426 */
1427 if (uap->port.irq == 0 &&
1428 np->parent && np->parent->parent &&
1429 of_device_is_compatible(np->parent->parent, "gatwick")) {
1430 /* IRQs on gatwick are offset by 64 */
1431 uap->port.irq = irq_create_mapping(NULL, 64 + 15);
1432 }
1433
1434 /* Setup some valid baud rate information in the register
1435 * shadows so we don't write crap there before baud rate is
1436 * first initialized.
1437 */
1438 pmz_convert_to_zs(uap, CS8, 0, 9600);
1439
1440 return 0;
1441 }
1442
1443 /*
1444 * Get rid of a port on module removal
1445 */
pmz_dispose_port(struct uart_pmac_port * uap)1446 static void pmz_dispose_port(struct uart_pmac_port *uap)
1447 {
1448 struct device_node *np;
1449
1450 np = uap->node;
1451 iounmap(uap->control_reg);
1452 uap->node = NULL;
1453 of_node_put(np);
1454 memset(uap, 0, sizeof(struct uart_pmac_port));
1455 }
1456
1457 /*
1458 * Called upon match with an escc node in the device-tree.
1459 */
pmz_attach(struct macio_dev * mdev,const struct of_device_id * match)1460 static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1461 {
1462 struct uart_pmac_port *uap;
1463 int i;
1464
1465 /* Iterate the pmz_ports array to find a matching entry
1466 */
1467 for (i = 0; i < MAX_ZS_PORTS; i++)
1468 if (pmz_ports[i].node == mdev->ofdev.dev.of_node)
1469 break;
1470 if (i >= MAX_ZS_PORTS)
1471 return -ENODEV;
1472
1473
1474 uap = &pmz_ports[i];
1475 uap->dev = mdev;
1476 uap->port.dev = &mdev->ofdev.dev;
1477 dev_set_drvdata(&mdev->ofdev.dev, uap);
1478
1479 /* We still activate the port even when failing to request resources
1480 * to work around bugs in ancient Apple device-trees
1481 */
1482 if (macio_request_resources(uap->dev, "pmac_zilog"))
1483 printk(KERN_WARNING "%pOFn: Failed to request resource"
1484 ", port still active\n",
1485 uap->node);
1486 else
1487 uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1488
1489 return uart_add_one_port(&pmz_uart_reg, &uap->port);
1490 }
1491
1492 /*
1493 * That one should not be called, macio isn't really a hotswap device,
1494 * we don't expect one of those serial ports to go away...
1495 */
pmz_detach(struct macio_dev * mdev)1496 static void pmz_detach(struct macio_dev *mdev)
1497 {
1498 struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1499
1500 if (!uap)
1501 return;
1502
1503 uart_remove_one_port(&pmz_uart_reg, &uap->port);
1504
1505 if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1506 macio_release_resources(uap->dev);
1507 uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1508 }
1509 dev_set_drvdata(&mdev->ofdev.dev, NULL);
1510 uap->dev = NULL;
1511 uap->port.dev = NULL;
1512 }
1513
pmz_suspend(struct macio_dev * mdev,pm_message_t pm_state)1514 static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1515 {
1516 struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1517
1518 if (uap == NULL) {
1519 printk("HRM... pmz_suspend with NULL uap\n");
1520 return 0;
1521 }
1522
1523 uart_suspend_port(&pmz_uart_reg, &uap->port);
1524
1525 return 0;
1526 }
1527
1528
pmz_resume(struct macio_dev * mdev)1529 static int pmz_resume(struct macio_dev *mdev)
1530 {
1531 struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1532
1533 if (uap == NULL)
1534 return 0;
1535
1536 uart_resume_port(&pmz_uart_reg, &uap->port);
1537
1538 return 0;
1539 }
1540
1541 /*
1542 * Probe all ports in the system and build the ports array, we register
1543 * with the serial layer later, so we get a proper struct device which
1544 * allows the tty to attach properly. This is later than it used to be
1545 * but the tty layer really wants it that way.
1546 */
pmz_probe(void)1547 static int __init pmz_probe(void)
1548 {
1549 struct device_node *node_p, *node_a, *node_b, *np;
1550 int count = 0;
1551 int rc;
1552
1553 /*
1554 * Find all escc chips in the system
1555 */
1556 for_each_node_by_name(node_p, "escc") {
1557 /*
1558 * First get channel A/B node pointers
1559 *
1560 * TODO: Add routines with proper locking to do that...
1561 */
1562 node_a = node_b = NULL;
1563 for_each_child_of_node(node_p, np) {
1564 if (of_node_name_prefix(np, "ch-a"))
1565 node_a = of_node_get(np);
1566 else if (of_node_name_prefix(np, "ch-b"))
1567 node_b = of_node_get(np);
1568 }
1569 if (!node_a && !node_b) {
1570 of_node_put(node_a);
1571 of_node_put(node_b);
1572 printk(KERN_ERR "pmac_zilog: missing node %c for escc %pOF\n",
1573 (!node_a) ? 'a' : 'b', node_p);
1574 continue;
1575 }
1576
1577 /*
1578 * Fill basic fields in the port structures
1579 */
1580 if (node_b != NULL) {
1581 pmz_ports[count].mate = &pmz_ports[count+1];
1582 pmz_ports[count+1].mate = &pmz_ports[count];
1583 }
1584 pmz_ports[count].flags = PMACZILOG_FLAG_IS_CHANNEL_A;
1585 pmz_ports[count].node = node_a;
1586 pmz_ports[count+1].node = node_b;
1587 pmz_ports[count].port.line = count;
1588 pmz_ports[count+1].port.line = count+1;
1589
1590 /*
1591 * Setup the ports for real
1592 */
1593 rc = pmz_init_port(&pmz_ports[count]);
1594 if (rc == 0 && node_b != NULL)
1595 rc = pmz_init_port(&pmz_ports[count+1]);
1596 if (rc != 0) {
1597 of_node_put(node_a);
1598 of_node_put(node_b);
1599 memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1600 memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1601 continue;
1602 }
1603 count += 2;
1604 }
1605 pmz_ports_count = count;
1606
1607 return 0;
1608 }
1609
1610 #else
1611
1612 /* On PCI PowerMacs, pmz_probe() does an explicit search of the OpenFirmware
1613 * tree to obtain the device_nodes needed to start the console before the
1614 * macio driver. On Macs without OpenFirmware, global platform_devices take
1615 * the place of those device_nodes.
1616 */
1617 extern struct platform_device scc_a_pdev, scc_b_pdev;
1618
pmz_init_port(struct uart_pmac_port * uap)1619 static int __init pmz_init_port(struct uart_pmac_port *uap)
1620 {
1621 struct resource *r_ports;
1622 int irq;
1623
1624 r_ports = platform_get_resource(uap->pdev, IORESOURCE_MEM, 0);
1625 if (!r_ports)
1626 return -ENODEV;
1627
1628 irq = platform_get_irq(uap->pdev, 0);
1629 if (irq < 0)
1630 return irq;
1631
1632 uap->port.mapbase = r_ports->start;
1633 uap->port.membase = (unsigned char __iomem *) r_ports->start;
1634 uap->port.iotype = UPIO_MEM;
1635 uap->port.irq = irq;
1636 uap->port.uartclk = ZS_CLOCK;
1637 uap->port.fifosize = 1;
1638 uap->port.ops = &pmz_pops;
1639 uap->port.type = PORT_PMAC_ZILOG;
1640 uap->port.flags = 0;
1641
1642 uap->control_reg = uap->port.membase;
1643 uap->data_reg = uap->control_reg + 4;
1644 uap->port_type = 0;
1645 uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PMACZILOG_CONSOLE);
1646
1647 pmz_convert_to_zs(uap, CS8, 0, 9600);
1648
1649 return 0;
1650 }
1651
pmz_probe(void)1652 static int __init pmz_probe(void)
1653 {
1654 int err;
1655
1656 pmz_ports_count = 0;
1657
1658 pmz_ports[0].port.line = 0;
1659 pmz_ports[0].flags = PMACZILOG_FLAG_IS_CHANNEL_A;
1660 pmz_ports[0].pdev = &scc_a_pdev;
1661 err = pmz_init_port(&pmz_ports[0]);
1662 if (err)
1663 return err;
1664 pmz_ports_count++;
1665
1666 pmz_ports[0].mate = &pmz_ports[1];
1667 pmz_ports[1].mate = &pmz_ports[0];
1668 pmz_ports[1].port.line = 1;
1669 pmz_ports[1].flags = 0;
1670 pmz_ports[1].pdev = &scc_b_pdev;
1671 err = pmz_init_port(&pmz_ports[1]);
1672 if (err)
1673 return err;
1674 pmz_ports_count++;
1675
1676 return 0;
1677 }
1678
pmz_dispose_port(struct uart_pmac_port * uap)1679 static void pmz_dispose_port(struct uart_pmac_port *uap)
1680 {
1681 memset(uap, 0, sizeof(struct uart_pmac_port));
1682 }
1683
pmz_attach(struct platform_device * pdev)1684 static int pmz_attach(struct platform_device *pdev)
1685 {
1686 struct uart_pmac_port *uap;
1687 int i;
1688
1689 /* Iterate the pmz_ports array to find a matching entry */
1690 for (i = 0; i < pmz_ports_count; i++)
1691 if (pmz_ports[i].pdev == pdev)
1692 break;
1693 if (i >= pmz_ports_count)
1694 return -ENODEV;
1695
1696 uap = &pmz_ports[i];
1697 uap->port.dev = &pdev->dev;
1698 platform_set_drvdata(pdev, uap);
1699
1700 return uart_add_one_port(&pmz_uart_reg, &uap->port);
1701 }
1702
pmz_detach(struct platform_device * pdev)1703 static void pmz_detach(struct platform_device *pdev)
1704 {
1705 struct uart_pmac_port *uap = platform_get_drvdata(pdev);
1706
1707 uart_remove_one_port(&pmz_uart_reg, &uap->port);
1708
1709 uap->port.dev = NULL;
1710 }
1711
1712 #endif /* !CONFIG_PPC_PMAC */
1713
1714 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1715
1716 static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1717 static int __init pmz_console_setup(struct console *co, char *options);
1718
1719 static struct console pmz_console = {
1720 .name = PMACZILOG_NAME,
1721 .write = pmz_console_write,
1722 .device = uart_console_device,
1723 .setup = pmz_console_setup,
1724 .flags = CON_PRINTBUFFER,
1725 .index = -1,
1726 .data = &pmz_uart_reg,
1727 };
1728
1729 #define PMACZILOG_CONSOLE &pmz_console
1730 #else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1731 #define PMACZILOG_CONSOLE (NULL)
1732 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1733
1734 /*
1735 * Register the driver, console driver and ports with the serial
1736 * core
1737 */
pmz_register(void)1738 static int __init pmz_register(void)
1739 {
1740 pmz_uart_reg.nr = pmz_ports_count;
1741 pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1742
1743 /*
1744 * Register this driver with the serial core
1745 */
1746 return uart_register_driver(&pmz_uart_reg);
1747 }
1748
1749 #ifdef CONFIG_PPC_PMAC
1750
1751 static const struct of_device_id pmz_match[] =
1752 {
1753 {
1754 .name = "ch-a",
1755 },
1756 {
1757 .name = "ch-b",
1758 },
1759 {},
1760 };
1761 MODULE_DEVICE_TABLE (of, pmz_match);
1762
1763 static struct macio_driver pmz_driver = {
1764 .driver = {
1765 .name = "pmac_zilog",
1766 .owner = THIS_MODULE,
1767 .of_match_table = pmz_match,
1768 },
1769 .probe = pmz_attach,
1770 .remove = pmz_detach,
1771 .suspend = pmz_suspend,
1772 .resume = pmz_resume,
1773 };
1774
1775 #else
1776
1777 static struct platform_driver pmz_driver = {
1778 .probe = pmz_attach,
1779 .remove = pmz_detach,
1780 .driver = {
1781 .name = "scc",
1782 },
1783 };
1784
1785 #endif /* !CONFIG_PPC_PMAC */
1786
init_pmz(void)1787 static int __init init_pmz(void)
1788 {
1789 int rc, i;
1790
1791 /*
1792 * First, we need to do a direct OF-based probe pass. We
1793 * do that because we want serial console up before the
1794 * macio stuffs calls us back, and since that makes it
1795 * easier to pass the proper number of channels to
1796 * uart_register_driver()
1797 */
1798 if (pmz_ports_count == 0)
1799 pmz_probe();
1800
1801 /*
1802 * Bail early if no port found
1803 */
1804 if (pmz_ports_count == 0)
1805 return -ENODEV;
1806
1807 /*
1808 * Now we register with the serial layer
1809 */
1810 rc = pmz_register();
1811 if (rc) {
1812 printk(KERN_ERR
1813 "pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
1814 "pmac_zilog: Did another serial driver already claim the minors?\n");
1815 /* effectively "pmz_unprobe()" */
1816 for (i=0; i < pmz_ports_count; i++)
1817 pmz_dispose_port(&pmz_ports[i]);
1818 return rc;
1819 }
1820
1821 /*
1822 * Then we register the macio driver itself
1823 */
1824 #ifdef CONFIG_PPC_PMAC
1825 return macio_register_driver(&pmz_driver);
1826 #else
1827 return platform_driver_register(&pmz_driver);
1828 #endif
1829 }
1830
exit_pmz(void)1831 static void __exit exit_pmz(void)
1832 {
1833 int i;
1834
1835 #ifdef CONFIG_PPC_PMAC
1836 /* Get rid of macio-driver (detach from macio) */
1837 macio_unregister_driver(&pmz_driver);
1838 #else
1839 platform_driver_unregister(&pmz_driver);
1840 #endif
1841
1842 for (i = 0; i < pmz_ports_count; i++) {
1843 struct uart_pmac_port *uport = &pmz_ports[i];
1844 #ifdef CONFIG_PPC_PMAC
1845 if (uport->node != NULL)
1846 pmz_dispose_port(uport);
1847 #else
1848 if (uport->pdev != NULL)
1849 pmz_dispose_port(uport);
1850 #endif
1851 }
1852 /* Unregister UART driver */
1853 uart_unregister_driver(&pmz_uart_reg);
1854 }
1855
1856 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1857
pmz_console_putchar(struct uart_port * port,unsigned char ch)1858 static void pmz_console_putchar(struct uart_port *port, unsigned char ch)
1859 {
1860 struct uart_pmac_port *uap =
1861 container_of(port, struct uart_pmac_port, port);
1862
1863 /* Wait for the transmit buffer to empty. */
1864 while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1865 udelay(5);
1866 write_zsdata(uap, ch);
1867 }
1868
1869 /*
1870 * Print a string to the serial port trying not to disturb
1871 * any possible real use of the port...
1872 */
pmz_console_write(struct console * con,const char * s,unsigned int count)1873 static void pmz_console_write(struct console *con, const char *s, unsigned int count)
1874 {
1875 struct uart_pmac_port *uap = &pmz_ports[con->index];
1876 unsigned long flags;
1877
1878 uart_port_lock_irqsave(&uap->port, &flags);
1879
1880 /* Turn of interrupts and enable the transmitter. */
1881 write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
1882 write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
1883
1884 uart_console_write(&uap->port, s, count, pmz_console_putchar);
1885
1886 /* Restore the values in the registers. */
1887 write_zsreg(uap, R1, uap->curregs[1]);
1888 /* Don't disable the transmitter. */
1889
1890 uart_port_unlock_irqrestore(&uap->port, flags);
1891 }
1892
1893 /*
1894 * Setup the serial console
1895 */
pmz_console_setup(struct console * co,char * options)1896 static int __init pmz_console_setup(struct console *co, char *options)
1897 {
1898 struct uart_pmac_port *uap;
1899 struct uart_port *port;
1900 int baud = 38400;
1901 int bits = 8;
1902 int parity = 'n';
1903 int flow = 'n';
1904 unsigned long pwr_delay;
1905
1906 /*
1907 * XServe's default to 57600 bps
1908 */
1909 if (of_machine_is_compatible("RackMac1,1")
1910 || of_machine_is_compatible("RackMac1,2")
1911 || of_machine_is_compatible("MacRISC4"))
1912 baud = 57600;
1913
1914 /*
1915 * Check whether an invalid uart number has been specified, and
1916 * if so, search for the first available port that does have
1917 * console support.
1918 */
1919 if (co->index >= pmz_ports_count)
1920 co->index = 0;
1921 uap = &pmz_ports[co->index];
1922 #ifdef CONFIG_PPC_PMAC
1923 if (uap->node == NULL)
1924 return -ENODEV;
1925 #else
1926 if (uap->pdev == NULL)
1927 return -ENODEV;
1928 #endif
1929 port = &uap->port;
1930
1931 /*
1932 * Mark port as beeing a console
1933 */
1934 uap->flags |= PMACZILOG_FLAG_IS_CONS;
1935
1936 /*
1937 * Temporary fix for uart layer who didn't setup the spinlock yet
1938 */
1939 spin_lock_init(&port->lock);
1940
1941 /*
1942 * Enable the hardware
1943 */
1944 pwr_delay = __pmz_startup(uap);
1945 if (pwr_delay)
1946 mdelay(pwr_delay);
1947
1948 if (options)
1949 uart_parse_options(options, &baud, &parity, &bits, &flow);
1950
1951 return uart_set_options(port, co, baud, parity, bits, flow);
1952 }
1953
pmz_console_init(void)1954 static int __init pmz_console_init(void)
1955 {
1956 /* Probe ports */
1957 pmz_probe();
1958
1959 if (pmz_ports_count == 0)
1960 return -ENODEV;
1961
1962 /* TODO: Autoprobe console based on OF */
1963 /* pmz_console.index = i; */
1964 register_console(&pmz_console);
1965
1966 return 0;
1967
1968 }
1969 console_initcall(pmz_console_init);
1970 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1971
1972 module_init(init_pmz);
1973 module_exit(exit_pmz);
1974