1 // SPDX-License-Identifier: GPL-2.0+
2 /************************************************************************
3 * Copyright 2003 Digi International (www.digi.com)
4 *
5 * Copyright (C) 2004 IBM Corporation. All rights reserved.
6 *
7 * Contact Information:
8 * Scott H Kilau <Scott_Kilau@digi.com>
9 * Wendy Xiong <wendyx@us.ibm.com>
10 *
11 ***********************************************************************/
12 #include <linux/delay.h> /* For udelay */
13 #include <linux/serial_reg.h> /* For the various UART offsets */
14 #include <linux/tty.h>
15 #include <linux/pci.h>
16 #include <asm/io.h>
17
18 #include "jsm.h" /* Driver main header file */
19
20 static u32 jsm_offset_table[8] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };
21
22 /*
23 * This function allows calls to ensure that all outstanding
24 * PCI writes have been completed, by doing a PCI read against
25 * a non-destructive, read-only location on the Neo card.
26 *
27 * In this case, we are reading the DVID (Read-only Device Identification)
28 * value of the Neo card.
29 */
neo_pci_posting_flush(struct jsm_board * bd)30 static inline void neo_pci_posting_flush(struct jsm_board *bd)
31 {
32 readb(bd->re_map_membase + 0x8D);
33 }
34
neo_set_cts_flow_control(struct jsm_channel * ch)35 static void neo_set_cts_flow_control(struct jsm_channel *ch)
36 {
37 u8 ier, efr;
38 ier = readb(&ch->ch_neo_uart->ier);
39 efr = readb(&ch->ch_neo_uart->efr);
40
41 jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting CTSFLOW\n");
42
43 /* Turn on auto CTS flow control */
44 ier |= (UART_17158_IER_CTSDSR);
45 efr |= (UART_17158_EFR_ECB | UART_17158_EFR_CTSDSR);
46
47 /* Turn off auto Xon flow control */
48 efr &= ~(UART_17158_EFR_IXON);
49
50 /* Why? Becuz Exar's spec says we have to zero it out before setting it */
51 writeb(0, &ch->ch_neo_uart->efr);
52
53 /* Turn on UART enhanced bits */
54 writeb(efr, &ch->ch_neo_uart->efr);
55
56 /* Turn on table D, with 8 char hi/low watermarks */
57 writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
58
59 /* Feed the UART our trigger levels */
60 writeb(8, &ch->ch_neo_uart->tfifo);
61 ch->ch_t_tlevel = 8;
62
63 writeb(ier, &ch->ch_neo_uart->ier);
64 }
65
neo_set_rts_flow_control(struct jsm_channel * ch)66 static void neo_set_rts_flow_control(struct jsm_channel *ch)
67 {
68 u8 ier, efr;
69 ier = readb(&ch->ch_neo_uart->ier);
70 efr = readb(&ch->ch_neo_uart->efr);
71
72 jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting RTSFLOW\n");
73
74 /* Turn on auto RTS flow control */
75 ier |= (UART_17158_IER_RTSDTR);
76 efr |= (UART_17158_EFR_ECB | UART_17158_EFR_RTSDTR);
77
78 /* Turn off auto Xoff flow control */
79 ier &= ~(UART_17158_IER_XOFF);
80 efr &= ~(UART_17158_EFR_IXOFF);
81
82 /* Why? Becuz Exar's spec says we have to zero it out before setting it */
83 writeb(0, &ch->ch_neo_uart->efr);
84
85 /* Turn on UART enhanced bits */
86 writeb(efr, &ch->ch_neo_uart->efr);
87
88 writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
89 ch->ch_r_watermark = 4;
90
91 writeb(56, &ch->ch_neo_uart->rfifo);
92 ch->ch_r_tlevel = 56;
93
94 writeb(ier, &ch->ch_neo_uart->ier);
95
96 /*
97 * From the Neo UART spec sheet:
98 * The auto RTS/DTR function must be started by asserting
99 * RTS/DTR# output pin (MCR bit-0 or 1 to logic 1 after
100 * it is enabled.
101 */
102 ch->ch_mostat |= (UART_MCR_RTS);
103 }
104
105
neo_set_ixon_flow_control(struct jsm_channel * ch)106 static void neo_set_ixon_flow_control(struct jsm_channel *ch)
107 {
108 u8 ier, efr;
109 ier = readb(&ch->ch_neo_uart->ier);
110 efr = readb(&ch->ch_neo_uart->efr);
111
112 jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXON FLOW\n");
113
114 /* Turn off auto CTS flow control */
115 ier &= ~(UART_17158_IER_CTSDSR);
116 efr &= ~(UART_17158_EFR_CTSDSR);
117
118 /* Turn on auto Xon flow control */
119 efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXON);
120
121 /* Why? Becuz Exar's spec says we have to zero it out before setting it */
122 writeb(0, &ch->ch_neo_uart->efr);
123
124 /* Turn on UART enhanced bits */
125 writeb(efr, &ch->ch_neo_uart->efr);
126
127 writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
128 ch->ch_r_watermark = 4;
129
130 writeb(32, &ch->ch_neo_uart->rfifo);
131 ch->ch_r_tlevel = 32;
132
133 /* Tell UART what start/stop chars it should be looking for */
134 writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
135 writeb(0, &ch->ch_neo_uart->xonchar2);
136
137 writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
138 writeb(0, &ch->ch_neo_uart->xoffchar2);
139
140 writeb(ier, &ch->ch_neo_uart->ier);
141 }
142
neo_set_ixoff_flow_control(struct jsm_channel * ch)143 static void neo_set_ixoff_flow_control(struct jsm_channel *ch)
144 {
145 u8 ier, efr;
146 ier = readb(&ch->ch_neo_uart->ier);
147 efr = readb(&ch->ch_neo_uart->efr);
148
149 jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXOFF FLOW\n");
150
151 /* Turn off auto RTS flow control */
152 ier &= ~(UART_17158_IER_RTSDTR);
153 efr &= ~(UART_17158_EFR_RTSDTR);
154
155 /* Turn on auto Xoff flow control */
156 ier |= (UART_17158_IER_XOFF);
157 efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
158
159 /* Why? Becuz Exar's spec says we have to zero it out before setting it */
160 writeb(0, &ch->ch_neo_uart->efr);
161
162 /* Turn on UART enhanced bits */
163 writeb(efr, &ch->ch_neo_uart->efr);
164
165 /* Turn on table D, with 8 char hi/low watermarks */
166 writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
167
168 writeb(8, &ch->ch_neo_uart->tfifo);
169 ch->ch_t_tlevel = 8;
170
171 /* Tell UART what start/stop chars it should be looking for */
172 writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
173 writeb(0, &ch->ch_neo_uart->xonchar2);
174
175 writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
176 writeb(0, &ch->ch_neo_uart->xoffchar2);
177
178 writeb(ier, &ch->ch_neo_uart->ier);
179 }
180
neo_set_no_input_flow_control(struct jsm_channel * ch)181 static void neo_set_no_input_flow_control(struct jsm_channel *ch)
182 {
183 u8 ier, efr;
184 ier = readb(&ch->ch_neo_uart->ier);
185 efr = readb(&ch->ch_neo_uart->efr);
186
187 jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Input FLOW\n");
188
189 /* Turn off auto RTS flow control */
190 ier &= ~(UART_17158_IER_RTSDTR);
191 efr &= ~(UART_17158_EFR_RTSDTR);
192
193 /* Turn off auto Xoff flow control */
194 ier &= ~(UART_17158_IER_XOFF);
195 if (ch->ch_c_iflag & IXON)
196 efr &= ~(UART_17158_EFR_IXOFF);
197 else
198 efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
199
200 /* Why? Becuz Exar's spec says we have to zero it out before setting it */
201 writeb(0, &ch->ch_neo_uart->efr);
202
203 /* Turn on UART enhanced bits */
204 writeb(efr, &ch->ch_neo_uart->efr);
205
206 /* Turn on table D, with 8 char hi/low watermarks */
207 writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
208
209 ch->ch_r_watermark = 0;
210
211 writeb(16, &ch->ch_neo_uart->tfifo);
212 ch->ch_t_tlevel = 16;
213
214 writeb(16, &ch->ch_neo_uart->rfifo);
215 ch->ch_r_tlevel = 16;
216
217 writeb(ier, &ch->ch_neo_uart->ier);
218 }
219
neo_set_no_output_flow_control(struct jsm_channel * ch)220 static void neo_set_no_output_flow_control(struct jsm_channel *ch)
221 {
222 u8 ier, efr;
223 ier = readb(&ch->ch_neo_uart->ier);
224 efr = readb(&ch->ch_neo_uart->efr);
225
226 jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Output FLOW\n");
227
228 /* Turn off auto CTS flow control */
229 ier &= ~(UART_17158_IER_CTSDSR);
230 efr &= ~(UART_17158_EFR_CTSDSR);
231
232 /* Turn off auto Xon flow control */
233 if (ch->ch_c_iflag & IXOFF)
234 efr &= ~(UART_17158_EFR_IXON);
235 else
236 efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXON);
237
238 /* Why? Becuz Exar's spec says we have to zero it out before setting it */
239 writeb(0, &ch->ch_neo_uart->efr);
240
241 /* Turn on UART enhanced bits */
242 writeb(efr, &ch->ch_neo_uart->efr);
243
244 /* Turn on table D, with 8 char hi/low watermarks */
245 writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
246
247 ch->ch_r_watermark = 0;
248
249 writeb(16, &ch->ch_neo_uart->tfifo);
250 ch->ch_t_tlevel = 16;
251
252 writeb(16, &ch->ch_neo_uart->rfifo);
253 ch->ch_r_tlevel = 16;
254
255 writeb(ier, &ch->ch_neo_uart->ier);
256 }
257
neo_set_new_start_stop_chars(struct jsm_channel * ch)258 static inline void neo_set_new_start_stop_chars(struct jsm_channel *ch)
259 {
260
261 /* if hardware flow control is set, then skip this whole thing */
262 if (ch->ch_c_cflag & CRTSCTS)
263 return;
264
265 jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "start\n");
266
267 /* Tell UART what start/stop chars it should be looking for */
268 writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
269 writeb(0, &ch->ch_neo_uart->xonchar2);
270
271 writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
272 writeb(0, &ch->ch_neo_uart->xoffchar2);
273 }
274
neo_copy_data_from_uart_to_queue(struct jsm_channel * ch)275 static void neo_copy_data_from_uart_to_queue(struct jsm_channel *ch)
276 {
277 int qleft = 0;
278 u8 linestatus = 0;
279 u8 error_mask = 0;
280 int n = 0;
281 int total = 0;
282 u16 head;
283 u16 tail;
284
285 /* cache head and tail of queue */
286 head = ch->ch_r_head & RQUEUEMASK;
287 tail = ch->ch_r_tail & RQUEUEMASK;
288
289 /* Get our cached LSR */
290 linestatus = ch->ch_cached_lsr;
291 ch->ch_cached_lsr = 0;
292
293 /* Store how much space we have left in the queue */
294 if ((qleft = tail - head - 1) < 0)
295 qleft += RQUEUEMASK + 1;
296
297 /*
298 * If the UART is not in FIFO mode, force the FIFO copy to
299 * NOT be run, by setting total to 0.
300 *
301 * On the other hand, if the UART IS in FIFO mode, then ask
302 * the UART to give us an approximation of data it has RX'ed.
303 */
304 if (!(ch->ch_flags & CH_FIFO_ENABLED))
305 total = 0;
306 else {
307 total = readb(&ch->ch_neo_uart->rfifo);
308
309 /*
310 * EXAR chip bug - RX FIFO COUNT - Fudge factor.
311 *
312 * This resolves a problem/bug with the Exar chip that sometimes
313 * returns a bogus value in the rfifo register.
314 * The count can be any where from 0-3 bytes "off".
315 * Bizarre, but true.
316 */
317 total -= 3;
318 }
319
320 /*
321 * Finally, bound the copy to make sure we don't overflow
322 * our own queue...
323 * The byte by byte copy loop below this loop this will
324 * deal with the queue overflow possibility.
325 */
326 total = min(total, qleft);
327
328 while (total > 0) {
329 /*
330 * Grab the linestatus register, we need to check
331 * to see if there are any errors in the FIFO.
332 */
333 linestatus = readb(&ch->ch_neo_uart->lsr);
334
335 /*
336 * Break out if there is a FIFO error somewhere.
337 * This will allow us to go byte by byte down below,
338 * finding the exact location of the error.
339 */
340 if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
341 break;
342
343 /* Make sure we don't go over the end of our queue */
344 n = min(((u32) total), (RQUEUESIZE - (u32) head));
345
346 /*
347 * Cut down n even further if needed, this is to fix
348 * a problem with memcpy_fromio() with the Neo on the
349 * IBM pSeries platform.
350 * 15 bytes max appears to be the magic number.
351 */
352 n = min((u32) n, (u32) 12);
353
354 /*
355 * Since we are grabbing the linestatus register, which
356 * will reset some bits after our read, we need to ensure
357 * we don't miss our TX FIFO emptys.
358 */
359 if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR))
360 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
361
362 linestatus = 0;
363
364 /* Copy data from uart to the queue */
365 memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, n);
366 /*
367 * Since RX_FIFO_DATA_ERROR was 0, we are guaranteed
368 * that all the data currently in the FIFO is free of
369 * breaks and parity/frame/orun errors.
370 */
371 memset(ch->ch_equeue + head, 0, n);
372
373 /* Add to and flip head if needed */
374 head = (head + n) & RQUEUEMASK;
375 total -= n;
376 qleft -= n;
377 ch->ch_rxcount += n;
378 }
379
380 /*
381 * Create a mask to determine whether we should
382 * insert the character (if any) into our queue.
383 */
384 if (ch->ch_c_iflag & IGNBRK)
385 error_mask |= UART_LSR_BI;
386
387 /*
388 * Now cleanup any leftover bytes still in the UART.
389 * Also deal with any possible queue overflow here as well.
390 */
391 while (1) {
392
393 /*
394 * Its possible we have a linestatus from the loop above
395 * this, so we "OR" on any extra bits.
396 */
397 linestatus |= readb(&ch->ch_neo_uart->lsr);
398
399 /*
400 * If the chip tells us there is no more data pending to
401 * be read, we can then leave.
402 * But before we do, cache the linestatus, just in case.
403 */
404 if (!(linestatus & UART_LSR_DR)) {
405 ch->ch_cached_lsr = linestatus;
406 break;
407 }
408
409 /* No need to store this bit */
410 linestatus &= ~UART_LSR_DR;
411
412 /*
413 * Since we are grabbing the linestatus register, which
414 * will reset some bits after our read, we need to ensure
415 * we don't miss our TX FIFO emptys.
416 */
417 if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR)) {
418 linestatus &= ~(UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR);
419 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
420 }
421
422 /*
423 * Discard character if we are ignoring the error mask.
424 */
425 if (linestatus & error_mask) {
426 u8 discard;
427 linestatus = 0;
428 memcpy_fromio(&discard, &ch->ch_neo_uart->txrxburst, 1);
429 continue;
430 }
431
432 /*
433 * If our queue is full, we have no choice but to drop some data.
434 * The assumption is that HWFLOW or SWFLOW should have stopped
435 * things way way before we got to this point.
436 *
437 * I decided that I wanted to ditch the oldest data first,
438 * I hope thats okay with everyone? Yes? Good.
439 */
440 while (qleft < 1) {
441 jsm_dbg(READ, &ch->ch_bd->pci_dev,
442 "Queue full, dropping DATA:%x LSR:%x\n",
443 ch->ch_rqueue[tail], ch->ch_equeue[tail]);
444
445 ch->ch_r_tail = tail = (tail + 1) & RQUEUEMASK;
446 ch->ch_err_overrun++;
447 qleft++;
448 }
449
450 memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, 1);
451 ch->ch_equeue[head] = (u8) linestatus;
452
453 jsm_dbg(READ, &ch->ch_bd->pci_dev, "DATA/LSR pair: %x %x\n",
454 ch->ch_rqueue[head], ch->ch_equeue[head]);
455
456 /* Ditch any remaining linestatus value. */
457 linestatus = 0;
458
459 /* Add to and flip head if needed */
460 head = (head + 1) & RQUEUEMASK;
461
462 qleft--;
463 ch->ch_rxcount++;
464 }
465
466 /*
467 * Write new final heads to channel structure.
468 */
469 ch->ch_r_head = head & RQUEUEMASK;
470 ch->ch_e_head = head & EQUEUEMASK;
471 jsm_input(ch);
472 }
473
neo_copy_data_from_queue_to_uart(struct jsm_channel * ch)474 static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch)
475 {
476 u16 head;
477 u16 tail;
478 int n;
479 int s;
480 int qlen;
481 u32 len_written = 0;
482 struct circ_buf *circ;
483
484 if (!ch)
485 return;
486
487 circ = &ch->uart_port.state->xmit;
488
489 /* No data to write to the UART */
490 if (uart_circ_empty(circ))
491 return;
492
493 /* If port is "stopped", don't send any data to the UART */
494 if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING))
495 return;
496 /*
497 * If FIFOs are disabled. Send data directly to txrx register
498 */
499 if (!(ch->ch_flags & CH_FIFO_ENABLED)) {
500 u8 lsrbits = readb(&ch->ch_neo_uart->lsr);
501
502 ch->ch_cached_lsr |= lsrbits;
503 if (ch->ch_cached_lsr & UART_LSR_THRE) {
504 ch->ch_cached_lsr &= ~(UART_LSR_THRE);
505
506 writeb(circ->buf[circ->tail], &ch->ch_neo_uart->txrx);
507 jsm_dbg(WRITE, &ch->ch_bd->pci_dev,
508 "Tx data: %x\n", circ->buf[circ->tail]);
509 circ->tail = (circ->tail + 1) & (UART_XMIT_SIZE - 1);
510 ch->ch_txcount++;
511 }
512 return;
513 }
514
515 /*
516 * We have to do it this way, because of the EXAR TXFIFO count bug.
517 */
518 if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))
519 return;
520
521 n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel;
522
523 /* cache head and tail of queue */
524 head = circ->head & (UART_XMIT_SIZE - 1);
525 tail = circ->tail & (UART_XMIT_SIZE - 1);
526 qlen = uart_circ_chars_pending(circ);
527
528 /* Find minimum of the FIFO space, versus queue length */
529 n = min(n, qlen);
530
531 while (n > 0) {
532
533 s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail;
534 s = min(s, n);
535
536 if (s <= 0)
537 break;
538
539 memcpy_toio(&ch->ch_neo_uart->txrxburst, circ->buf + tail, s);
540 /* Add and flip queue if needed */
541 tail = (tail + s) & (UART_XMIT_SIZE - 1);
542 n -= s;
543 ch->ch_txcount += s;
544 len_written += s;
545 }
546
547 /* Update the final tail */
548 circ->tail = tail & (UART_XMIT_SIZE - 1);
549
550 if (len_written >= ch->ch_t_tlevel)
551 ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
552
553 if (uart_circ_empty(circ))
554 uart_write_wakeup(&ch->uart_port);
555 }
556
neo_parse_modem(struct jsm_channel * ch,u8 signals)557 static void neo_parse_modem(struct jsm_channel *ch, u8 signals)
558 {
559 u8 msignals = signals;
560
561 jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
562 "neo_parse_modem: port: %d msignals: %x\n",
563 ch->ch_portnum, msignals);
564
565 /* Scrub off lower bits. They signify delta's, which I don't care about */
566 /* Keep DDCD and DDSR though */
567 msignals &= 0xf8;
568
569 if (msignals & UART_MSR_DDCD)
570 uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD);
571 if (msignals & UART_MSR_DDSR)
572 uart_handle_cts_change(&ch->uart_port, msignals & UART_MSR_CTS);
573 if (msignals & UART_MSR_DCD)
574 ch->ch_mistat |= UART_MSR_DCD;
575 else
576 ch->ch_mistat &= ~UART_MSR_DCD;
577
578 if (msignals & UART_MSR_DSR)
579 ch->ch_mistat |= UART_MSR_DSR;
580 else
581 ch->ch_mistat &= ~UART_MSR_DSR;
582
583 if (msignals & UART_MSR_RI)
584 ch->ch_mistat |= UART_MSR_RI;
585 else
586 ch->ch_mistat &= ~UART_MSR_RI;
587
588 if (msignals & UART_MSR_CTS)
589 ch->ch_mistat |= UART_MSR_CTS;
590 else
591 ch->ch_mistat &= ~UART_MSR_CTS;
592
593 jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
594 "Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
595 ch->ch_portnum,
596 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
597 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
598 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
599 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
600 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
601 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD));
602 }
603
604 /* Make the UART raise any of the output signals we want up */
neo_assert_modem_signals(struct jsm_channel * ch)605 static void neo_assert_modem_signals(struct jsm_channel *ch)
606 {
607 if (!ch)
608 return;
609
610 writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
611
612 /* flush write operation */
613 neo_pci_posting_flush(ch->ch_bd);
614 }
615
616 /*
617 * Flush the WRITE FIFO on the Neo.
618 *
619 * NOTE: Channel lock MUST be held before calling this function!
620 */
neo_flush_uart_write(struct jsm_channel * ch)621 static void neo_flush_uart_write(struct jsm_channel *ch)
622 {
623 u8 tmp = 0;
624 int i = 0;
625
626 if (!ch)
627 return;
628
629 writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
630
631 for (i = 0; i < 10; i++) {
632
633 /* Check to see if the UART feels it completely flushed the FIFO. */
634 tmp = readb(&ch->ch_neo_uart->isr_fcr);
635 if (tmp & UART_FCR_CLEAR_XMIT) {
636 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
637 "Still flushing TX UART... i: %d\n", i);
638 udelay(10);
639 }
640 else
641 break;
642 }
643
644 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
645 }
646
647
648 /*
649 * Flush the READ FIFO on the Neo.
650 *
651 * NOTE: Channel lock MUST be held before calling this function!
652 */
neo_flush_uart_read(struct jsm_channel * ch)653 static void neo_flush_uart_read(struct jsm_channel *ch)
654 {
655 u8 tmp = 0;
656 int i = 0;
657
658 if (!ch)
659 return;
660
661 writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr);
662
663 for (i = 0; i < 10; i++) {
664
665 /* Check to see if the UART feels it completely flushed the FIFO. */
666 tmp = readb(&ch->ch_neo_uart->isr_fcr);
667 if (tmp & 2) {
668 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
669 "Still flushing RX UART... i: %d\n", i);
670 udelay(10);
671 }
672 else
673 break;
674 }
675 }
676
677 /*
678 * No locks are assumed to be held when calling this function.
679 */
neo_clear_break(struct jsm_channel * ch)680 static void neo_clear_break(struct jsm_channel *ch)
681 {
682 unsigned long lock_flags;
683
684 spin_lock_irqsave(&ch->ch_lock, lock_flags);
685
686 /* Turn break off, and unset some variables */
687 if (ch->ch_flags & CH_BREAK_SENDING) {
688 u8 temp = readb(&ch->ch_neo_uart->lcr);
689 writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr);
690
691 ch->ch_flags &= ~(CH_BREAK_SENDING);
692 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
693 "clear break Finishing UART_LCR_SBC! finished: %lx\n",
694 jiffies);
695
696 /* flush write operation */
697 neo_pci_posting_flush(ch->ch_bd);
698 }
699 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
700 }
701
702 /*
703 * Parse the ISR register.
704 */
neo_parse_isr(struct jsm_board * brd,u32 port)705 static void neo_parse_isr(struct jsm_board *brd, u32 port)
706 {
707 struct jsm_channel *ch;
708 u8 isr;
709 u8 cause;
710 unsigned long lock_flags;
711
712 if (!brd)
713 return;
714
715 if (port >= brd->maxports)
716 return;
717
718 ch = brd->channels[port];
719 if (!ch)
720 return;
721
722 /* Here we try to figure out what caused the interrupt to happen */
723 while (1) {
724
725 isr = readb(&ch->ch_neo_uart->isr_fcr);
726
727 /* Bail if no pending interrupt */
728 if (isr & UART_IIR_NO_INT)
729 break;
730
731 /*
732 * Yank off the upper 2 bits, which just show that the FIFO's are enabled.
733 */
734 isr &= ~(UART_17158_IIR_FIFO_ENABLED);
735
736 jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d isr: %x\n",
737 __FILE__, __LINE__, isr);
738
739 if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) {
740 /* Read data from uart -> queue */
741 neo_copy_data_from_uart_to_queue(ch);
742
743 /* Call our tty layer to enforce queue flow control if needed. */
744 spin_lock_irqsave(&ch->ch_lock, lock_flags);
745 jsm_check_queue_flow_control(ch);
746 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
747 }
748
749 if (isr & UART_IIR_THRI) {
750 /* Transfer data (if any) from Write Queue -> UART. */
751 spin_lock_irqsave(&ch->ch_lock, lock_flags);
752 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
753 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
754 neo_copy_data_from_queue_to_uart(ch);
755 }
756
757 if (isr & UART_17158_IIR_XONXOFF) {
758 cause = readb(&ch->ch_neo_uart->xoffchar1);
759
760 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
761 "Port %d. Got ISR_XONXOFF: cause:%x\n",
762 port, cause);
763
764 /*
765 * Since the UART detected either an XON or
766 * XOFF match, we need to figure out which
767 * one it was, so we can suspend or resume data flow.
768 */
769 spin_lock_irqsave(&ch->ch_lock, lock_flags);
770 if (cause == UART_17158_XON_DETECT) {
771 /* Is output stopped right now, if so, resume it */
772 if (brd->channels[port]->ch_flags & CH_STOP) {
773 ch->ch_flags &= ~(CH_STOP);
774 }
775 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
776 "Port %d. XON detected in incoming data\n",
777 port);
778 }
779 else if (cause == UART_17158_XOFF_DETECT) {
780 if (!(brd->channels[port]->ch_flags & CH_STOP)) {
781 ch->ch_flags |= CH_STOP;
782 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
783 "Setting CH_STOP\n");
784 }
785 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
786 "Port: %d. XOFF detected in incoming data\n",
787 port);
788 }
789 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
790 }
791
792 if (isr & UART_17158_IIR_HWFLOW_STATE_CHANGE) {
793 /*
794 * If we get here, this means the hardware is doing auto flow control.
795 * Check to see whether RTS/DTR or CTS/DSR caused this interrupt.
796 */
797 cause = readb(&ch->ch_neo_uart->mcr);
798
799 /* Which pin is doing auto flow? RTS or DTR? */
800 spin_lock_irqsave(&ch->ch_lock, lock_flags);
801 if ((cause & 0x4) == 0) {
802 if (cause & UART_MCR_RTS)
803 ch->ch_mostat |= UART_MCR_RTS;
804 else
805 ch->ch_mostat &= ~(UART_MCR_RTS);
806 } else {
807 if (cause & UART_MCR_DTR)
808 ch->ch_mostat |= UART_MCR_DTR;
809 else
810 ch->ch_mostat &= ~(UART_MCR_DTR);
811 }
812 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
813 }
814
815 /* Parse any modem signal changes */
816 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
817 "MOD_STAT: sending to parse_modem_sigs\n");
818 neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
819 }
820 }
821
neo_parse_lsr(struct jsm_board * brd,u32 port)822 static inline void neo_parse_lsr(struct jsm_board *brd, u32 port)
823 {
824 struct jsm_channel *ch;
825 int linestatus;
826 unsigned long lock_flags;
827
828 if (!brd)
829 return;
830
831 if (port >= brd->maxports)
832 return;
833
834 ch = brd->channels[port];
835 if (!ch)
836 return;
837
838 linestatus = readb(&ch->ch_neo_uart->lsr);
839
840 jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d port: %d linestatus: %x\n",
841 __FILE__, __LINE__, port, linestatus);
842
843 ch->ch_cached_lsr |= linestatus;
844
845 if (ch->ch_cached_lsr & UART_LSR_DR) {
846 /* Read data from uart -> queue */
847 neo_copy_data_from_uart_to_queue(ch);
848 spin_lock_irqsave(&ch->ch_lock, lock_flags);
849 jsm_check_queue_flow_control(ch);
850 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
851 }
852
853 /*
854 * This is a special flag. It indicates that at least 1
855 * RX error (parity, framing, or break) has happened.
856 * Mark this in our struct, which will tell me that I have
857 *to do the special RX+LSR read for this FIFO load.
858 */
859 if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
860 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
861 "%s:%d Port: %d Got an RX error, need to parse LSR\n",
862 __FILE__, __LINE__, port);
863
864 /*
865 * The next 3 tests should *NOT* happen, as the above test
866 * should encapsulate all 3... At least, thats what Exar says.
867 */
868
869 if (linestatus & UART_LSR_PE) {
870 ch->ch_err_parity++;
871 jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. PAR ERR!\n",
872 __FILE__, __LINE__, port);
873 }
874
875 if (linestatus & UART_LSR_FE) {
876 ch->ch_err_frame++;
877 jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. FRM ERR!\n",
878 __FILE__, __LINE__, port);
879 }
880
881 if (linestatus & UART_LSR_BI) {
882 ch->ch_err_break++;
883 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
884 "%s:%d Port: %d. BRK INTR!\n",
885 __FILE__, __LINE__, port);
886 }
887
888 if (linestatus & UART_LSR_OE) {
889 /*
890 * Rx Oruns. Exar says that an orun will NOT corrupt
891 * the FIFO. It will just replace the holding register
892 * with this new data byte. So basically just ignore this.
893 * Probably we should eventually have an orun stat in our driver...
894 */
895 ch->ch_err_overrun++;
896 jsm_dbg(INTR, &ch->ch_bd->pci_dev,
897 "%s:%d Port: %d. Rx Overrun!\n",
898 __FILE__, __LINE__, port);
899 }
900
901 if (linestatus & UART_LSR_THRE) {
902 spin_lock_irqsave(&ch->ch_lock, lock_flags);
903 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
904 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
905
906 /* Transfer data (if any) from Write Queue -> UART. */
907 neo_copy_data_from_queue_to_uart(ch);
908 }
909 else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
910 spin_lock_irqsave(&ch->ch_lock, lock_flags);
911 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
912 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
913
914 /* Transfer data (if any) from Write Queue -> UART. */
915 neo_copy_data_from_queue_to_uart(ch);
916 }
917 }
918
919 /*
920 * neo_param()
921 * Send any/all changes to the line to the UART.
922 */
neo_param(struct jsm_channel * ch)923 static void neo_param(struct jsm_channel *ch)
924 {
925 u8 lcr = 0;
926 u8 uart_lcr, ier;
927 u32 baud;
928 int quot;
929 struct jsm_board *bd;
930
931 bd = ch->ch_bd;
932 if (!bd)
933 return;
934
935 /*
936 * If baud rate is zero, flush queues, and set mval to drop DTR.
937 */
938 if ((ch->ch_c_cflag & (CBAUD)) == 0) {
939 ch->ch_r_head = ch->ch_r_tail = 0;
940 ch->ch_e_head = ch->ch_e_tail = 0;
941
942 neo_flush_uart_write(ch);
943 neo_flush_uart_read(ch);
944
945 ch->ch_flags |= (CH_BAUD0);
946 ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
947 neo_assert_modem_signals(ch);
948 return;
949
950 } else {
951 int i;
952 unsigned int cflag;
953 static struct {
954 unsigned int rate;
955 unsigned int cflag;
956 } baud_rates[] = {
957 { 921600, B921600 },
958 { 460800, B460800 },
959 { 230400, B230400 },
960 { 115200, B115200 },
961 { 57600, B57600 },
962 { 38400, B38400 },
963 { 19200, B19200 },
964 { 9600, B9600 },
965 { 4800, B4800 },
966 { 2400, B2400 },
967 { 1200, B1200 },
968 { 600, B600 },
969 { 300, B300 },
970 { 200, B200 },
971 { 150, B150 },
972 { 134, B134 },
973 { 110, B110 },
974 { 75, B75 },
975 { 50, B50 },
976 };
977
978 cflag = C_BAUD(ch->uart_port.state->port.tty);
979 baud = 9600;
980 for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
981 if (baud_rates[i].cflag == cflag) {
982 baud = baud_rates[i].rate;
983 break;
984 }
985 }
986
987 if (ch->ch_flags & CH_BAUD0)
988 ch->ch_flags &= ~(CH_BAUD0);
989 }
990
991 if (ch->ch_c_cflag & PARENB)
992 lcr |= UART_LCR_PARITY;
993
994 if (!(ch->ch_c_cflag & PARODD))
995 lcr |= UART_LCR_EPAR;
996
997 /*
998 * Not all platforms support mark/space parity,
999 * so this will hide behind an ifdef.
1000 */
1001 #ifdef CMSPAR
1002 if (ch->ch_c_cflag & CMSPAR)
1003 lcr |= UART_LCR_SPAR;
1004 #endif
1005
1006 if (ch->ch_c_cflag & CSTOPB)
1007 lcr |= UART_LCR_STOP;
1008
1009 switch (ch->ch_c_cflag & CSIZE) {
1010 case CS5:
1011 lcr |= UART_LCR_WLEN5;
1012 break;
1013 case CS6:
1014 lcr |= UART_LCR_WLEN6;
1015 break;
1016 case CS7:
1017 lcr |= UART_LCR_WLEN7;
1018 break;
1019 case CS8:
1020 default:
1021 lcr |= UART_LCR_WLEN8;
1022 break;
1023 }
1024
1025 ier = readb(&ch->ch_neo_uart->ier);
1026 uart_lcr = readb(&ch->ch_neo_uart->lcr);
1027
1028 quot = ch->ch_bd->bd_dividend / baud;
1029
1030 if (quot != 0) {
1031 writeb(UART_LCR_DLAB, &ch->ch_neo_uart->lcr);
1032 writeb((quot & 0xff), &ch->ch_neo_uart->txrx);
1033 writeb((quot >> 8), &ch->ch_neo_uart->ier);
1034 writeb(lcr, &ch->ch_neo_uart->lcr);
1035 }
1036
1037 if (uart_lcr != lcr)
1038 writeb(lcr, &ch->ch_neo_uart->lcr);
1039
1040 if (ch->ch_c_cflag & CREAD)
1041 ier |= (UART_IER_RDI | UART_IER_RLSI);
1042
1043 ier |= (UART_IER_THRI | UART_IER_MSI);
1044
1045 writeb(ier, &ch->ch_neo_uart->ier);
1046
1047 /* Set new start/stop chars */
1048 neo_set_new_start_stop_chars(ch);
1049
1050 if (ch->ch_c_cflag & CRTSCTS)
1051 neo_set_cts_flow_control(ch);
1052 else if (ch->ch_c_iflag & IXON) {
1053 /* If start/stop is set to disable, then we should disable flow control */
1054 if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1055 neo_set_no_output_flow_control(ch);
1056 else
1057 neo_set_ixon_flow_control(ch);
1058 }
1059 else
1060 neo_set_no_output_flow_control(ch);
1061
1062 if (ch->ch_c_cflag & CRTSCTS)
1063 neo_set_rts_flow_control(ch);
1064 else if (ch->ch_c_iflag & IXOFF) {
1065 /* If start/stop is set to disable, then we should disable flow control */
1066 if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1067 neo_set_no_input_flow_control(ch);
1068 else
1069 neo_set_ixoff_flow_control(ch);
1070 }
1071 else
1072 neo_set_no_input_flow_control(ch);
1073 /*
1074 * Adjust the RX FIFO Trigger level if baud is less than 9600.
1075 * Not exactly elegant, but this is needed because of the Exar chip's
1076 * delay on firing off the RX FIFO interrupt on slower baud rates.
1077 */
1078 if (baud < 9600) {
1079 writeb(1, &ch->ch_neo_uart->rfifo);
1080 ch->ch_r_tlevel = 1;
1081 }
1082
1083 neo_assert_modem_signals(ch);
1084
1085 /* Get current status of the modem signals now */
1086 neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
1087 return;
1088 }
1089
1090 /*
1091 * jsm_neo_intr()
1092 *
1093 * Neo specific interrupt handler.
1094 */
neo_intr(int irq,void * voidbrd)1095 static irqreturn_t neo_intr(int irq, void *voidbrd)
1096 {
1097 struct jsm_board *brd = voidbrd;
1098 struct jsm_channel *ch;
1099 int port = 0;
1100 int type = 0;
1101 int current_port;
1102 u32 tmp;
1103 u32 uart_poll;
1104 unsigned long lock_flags;
1105 unsigned long lock_flags2;
1106 int outofloop_count = 0;
1107
1108 /* Lock out the slow poller from running on this board. */
1109 spin_lock_irqsave(&brd->bd_intr_lock, lock_flags);
1110
1111 /*
1112 * Read in "extended" IRQ information from the 32bit Neo register.
1113 * Bits 0-7: What port triggered the interrupt.
1114 * Bits 8-31: Each 3bits indicate what type of interrupt occurred.
1115 */
1116 uart_poll = readl(brd->re_map_membase + UART_17158_POLL_ADDR_OFFSET);
1117
1118 jsm_dbg(INTR, &brd->pci_dev, "%s:%d uart_poll: %x\n",
1119 __FILE__, __LINE__, uart_poll);
1120
1121 if (!uart_poll) {
1122 jsm_dbg(INTR, &brd->pci_dev,
1123 "Kernel interrupted to me, but no pending interrupts...\n");
1124 spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1125 return IRQ_NONE;
1126 }
1127
1128 /* At this point, we have at least SOMETHING to service, dig further... */
1129
1130 current_port = 0;
1131
1132 /* Loop on each port */
1133 while (((uart_poll & 0xff) != 0) && (outofloop_count < 0xff)){
1134
1135 tmp = uart_poll;
1136 outofloop_count++;
1137
1138 /* Check current port to see if it has interrupt pending */
1139 if ((tmp & jsm_offset_table[current_port]) != 0) {
1140 port = current_port;
1141 type = tmp >> (8 + (port * 3));
1142 type &= 0x7;
1143 } else {
1144 current_port++;
1145 continue;
1146 }
1147
1148 jsm_dbg(INTR, &brd->pci_dev, "%s:%d port: %x type: %x\n",
1149 __FILE__, __LINE__, port, type);
1150
1151 /* Remove this port + type from uart_poll */
1152 uart_poll &= ~(jsm_offset_table[port]);
1153
1154 if (!type) {
1155 /* If no type, just ignore it, and move onto next port */
1156 jsm_dbg(INTR, &brd->pci_dev,
1157 "Interrupt with no type! port: %d\n", port);
1158 continue;
1159 }
1160
1161 /* Switch on type of interrupt we have */
1162 switch (type) {
1163
1164 case UART_17158_RXRDY_TIMEOUT:
1165 /*
1166 * RXRDY Time-out is cleared by reading data in the
1167 * RX FIFO until it falls below the trigger level.
1168 */
1169
1170 /* Verify the port is in range. */
1171 if (port >= brd->nasync)
1172 continue;
1173
1174 ch = brd->channels[port];
1175 if (!ch)
1176 continue;
1177
1178 neo_copy_data_from_uart_to_queue(ch);
1179
1180 /* Call our tty layer to enforce queue flow control if needed. */
1181 spin_lock_irqsave(&ch->ch_lock, lock_flags2);
1182 jsm_check_queue_flow_control(ch);
1183 spin_unlock_irqrestore(&ch->ch_lock, lock_flags2);
1184
1185 continue;
1186
1187 case UART_17158_RX_LINE_STATUS:
1188 /*
1189 * RXRDY and RX LINE Status (logic OR of LSR[4:1])
1190 */
1191 neo_parse_lsr(brd, port);
1192 continue;
1193
1194 case UART_17158_TXRDY:
1195 /*
1196 * TXRDY interrupt clears after reading ISR register for the UART channel.
1197 */
1198
1199 /*
1200 * Yes, this is odd...
1201 * Why would I check EVERY possibility of type of
1202 * interrupt, when we know its TXRDY???
1203 * Becuz for some reason, even tho we got triggered for TXRDY,
1204 * it seems to be occasionally wrong. Instead of TX, which
1205 * it should be, I was getting things like RXDY too. Weird.
1206 */
1207 neo_parse_isr(brd, port);
1208 continue;
1209
1210 case UART_17158_MSR:
1211 /*
1212 * MSR or flow control was seen.
1213 */
1214 neo_parse_isr(brd, port);
1215 continue;
1216
1217 default:
1218 /*
1219 * The UART triggered us with a bogus interrupt type.
1220 * It appears the Exar chip, when REALLY bogged down, will throw
1221 * these once and awhile.
1222 * Its harmless, just ignore it and move on.
1223 */
1224 jsm_dbg(INTR, &brd->pci_dev,
1225 "%s:%d Unknown Interrupt type: %x\n",
1226 __FILE__, __LINE__, type);
1227 continue;
1228 }
1229 }
1230
1231 spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1232
1233 jsm_dbg(INTR, &brd->pci_dev, "finish\n");
1234 return IRQ_HANDLED;
1235 }
1236
1237 /*
1238 * Neo specific way of turning off the receiver.
1239 * Used as a way to enforce queue flow control when in
1240 * hardware flow control mode.
1241 */
neo_disable_receiver(struct jsm_channel * ch)1242 static void neo_disable_receiver(struct jsm_channel *ch)
1243 {
1244 u8 tmp = readb(&ch->ch_neo_uart->ier);
1245 tmp &= ~(UART_IER_RDI);
1246 writeb(tmp, &ch->ch_neo_uart->ier);
1247
1248 /* flush write operation */
1249 neo_pci_posting_flush(ch->ch_bd);
1250 }
1251
1252
1253 /*
1254 * Neo specific way of turning on the receiver.
1255 * Used as a way to un-enforce queue flow control when in
1256 * hardware flow control mode.
1257 */
neo_enable_receiver(struct jsm_channel * ch)1258 static void neo_enable_receiver(struct jsm_channel *ch)
1259 {
1260 u8 tmp = readb(&ch->ch_neo_uart->ier);
1261 tmp |= (UART_IER_RDI);
1262 writeb(tmp, &ch->ch_neo_uart->ier);
1263
1264 /* flush write operation */
1265 neo_pci_posting_flush(ch->ch_bd);
1266 }
1267
neo_send_start_character(struct jsm_channel * ch)1268 static void neo_send_start_character(struct jsm_channel *ch)
1269 {
1270 if (!ch)
1271 return;
1272
1273 if (ch->ch_startc != __DISABLED_CHAR) {
1274 ch->ch_xon_sends++;
1275 writeb(ch->ch_startc, &ch->ch_neo_uart->txrx);
1276
1277 /* flush write operation */
1278 neo_pci_posting_flush(ch->ch_bd);
1279 }
1280 }
1281
neo_send_stop_character(struct jsm_channel * ch)1282 static void neo_send_stop_character(struct jsm_channel *ch)
1283 {
1284 if (!ch)
1285 return;
1286
1287 if (ch->ch_stopc != __DISABLED_CHAR) {
1288 ch->ch_xoff_sends++;
1289 writeb(ch->ch_stopc, &ch->ch_neo_uart->txrx);
1290
1291 /* flush write operation */
1292 neo_pci_posting_flush(ch->ch_bd);
1293 }
1294 }
1295
1296 /*
1297 * neo_uart_init
1298 */
neo_uart_init(struct jsm_channel * ch)1299 static void neo_uart_init(struct jsm_channel *ch)
1300 {
1301 writeb(0, &ch->ch_neo_uart->ier);
1302 writeb(0, &ch->ch_neo_uart->efr);
1303 writeb(UART_EFR_ECB, &ch->ch_neo_uart->efr);
1304
1305 /* Clear out UART and FIFO */
1306 readb(&ch->ch_neo_uart->txrx);
1307 writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
1308 readb(&ch->ch_neo_uart->lsr);
1309 readb(&ch->ch_neo_uart->msr);
1310
1311 ch->ch_flags |= CH_FIFO_ENABLED;
1312
1313 /* Assert any signals we want up */
1314 writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
1315 }
1316
1317 /*
1318 * Make the UART completely turn off.
1319 */
neo_uart_off(struct jsm_channel * ch)1320 static void neo_uart_off(struct jsm_channel *ch)
1321 {
1322 /* Turn off UART enhanced bits */
1323 writeb(0, &ch->ch_neo_uart->efr);
1324
1325 /* Stop all interrupts from occurring. */
1326 writeb(0, &ch->ch_neo_uart->ier);
1327 }
1328
neo_get_uart_bytes_left(struct jsm_channel * ch)1329 static u32 neo_get_uart_bytes_left(struct jsm_channel *ch)
1330 {
1331 u8 left = 0;
1332 u8 lsr = readb(&ch->ch_neo_uart->lsr);
1333
1334 /* We must cache the LSR as some of the bits get reset once read... */
1335 ch->ch_cached_lsr |= lsr;
1336
1337 /* Determine whether the Transmitter is empty or not */
1338 if (!(lsr & UART_LSR_TEMT))
1339 left = 1;
1340 else {
1341 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1342 left = 0;
1343 }
1344
1345 return left;
1346 }
1347
1348 /* Channel lock MUST be held by the calling function! */
neo_send_break(struct jsm_channel * ch)1349 static void neo_send_break(struct jsm_channel *ch)
1350 {
1351 /*
1352 * Set the time we should stop sending the break.
1353 * If we are already sending a break, toss away the existing
1354 * time to stop, and use this new value instead.
1355 */
1356
1357 /* Tell the UART to start sending the break */
1358 if (!(ch->ch_flags & CH_BREAK_SENDING)) {
1359 u8 temp = readb(&ch->ch_neo_uart->lcr);
1360 writeb((temp | UART_LCR_SBC), &ch->ch_neo_uart->lcr);
1361 ch->ch_flags |= (CH_BREAK_SENDING);
1362
1363 /* flush write operation */
1364 neo_pci_posting_flush(ch->ch_bd);
1365 }
1366 }
1367
1368 /*
1369 * neo_send_immediate_char.
1370 *
1371 * Sends a specific character as soon as possible to the UART,
1372 * jumping over any bytes that might be in the write queue.
1373 *
1374 * The channel lock MUST be held by the calling function.
1375 */
neo_send_immediate_char(struct jsm_channel * ch,unsigned char c)1376 static void neo_send_immediate_char(struct jsm_channel *ch, unsigned char c)
1377 {
1378 if (!ch)
1379 return;
1380
1381 writeb(c, &ch->ch_neo_uart->txrx);
1382
1383 /* flush write operation */
1384 neo_pci_posting_flush(ch->ch_bd);
1385 }
1386
1387 struct board_ops jsm_neo_ops = {
1388 .intr = neo_intr,
1389 .uart_init = neo_uart_init,
1390 .uart_off = neo_uart_off,
1391 .param = neo_param,
1392 .assert_modem_signals = neo_assert_modem_signals,
1393 .flush_uart_write = neo_flush_uart_write,
1394 .flush_uart_read = neo_flush_uart_read,
1395 .disable_receiver = neo_disable_receiver,
1396 .enable_receiver = neo_enable_receiver,
1397 .send_break = neo_send_break,
1398 .clear_break = neo_clear_break,
1399 .send_start_character = neo_send_start_character,
1400 .send_stop_character = neo_send_stop_character,
1401 .copy_data_from_queue_to_uart = neo_copy_data_from_queue_to_uart,
1402 .get_uart_bytes_left = neo_get_uart_bytes_left,
1403 .send_immediate_char = neo_send_immediate_char
1404 };
1405
