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sh_eth: fix EESIPR values for SH77{34|63}
[linux/fpc-iii.git] / drivers / tty / serial / sunhv.c
blob99ef5c6e47669a4c32a19ce614c52189bf251f62
1 /* sunhv.c: Serial driver for SUN4V hypervisor console.
2 *
3 * Copyright (C) 2006, 2007 David S. Miller (davem@davemloft.net)
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/errno.h>
8 #include <linux/tty.h>
9 #include <linux/tty_flip.h>
10 #include <linux/major.h>
11 #include <linux/circ_buf.h>
12 #include <linux/serial.h>
13 #include <linux/sysrq.h>
14 #include <linux/console.h>
15 #include <linux/spinlock.h>
16 #include <linux/slab.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/of_device.h>
20
21 #include <asm/hypervisor.h>
22 #include <asm/spitfire.h>
23 #include <asm/prom.h>
24 #include <asm/irq.h>
25 #include <asm/setup.h>
26
27 #if defined(CONFIG_MAGIC_SYSRQ)
28 #define SUPPORT_SYSRQ
29 #endif
30
31 #include <linux/serial_core.h>
32 #include <linux/sunserialcore.h>
33
34 #define CON_BREAK ((long)-1)
35 #define CON_HUP ((long)-2)
36
37 #define IGNORE_BREAK 0x1
38 #define IGNORE_ALL 0x2
39
40 static char *con_write_page;
41 static char *con_read_page;
42
43 static int hung_up = 0;
44
45 static void transmit_chars_putchar(struct uart_port *port, struct circ_buf *xmit)
46 {
47 while (!uart_circ_empty(xmit)) {
48 long status = sun4v_con_putchar(xmit->buf[xmit->tail]);
49
50 if (status != HV_EOK)
51 break;
52
53 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
54 port->icount.tx++;
55 }
56 }
57
58 static void transmit_chars_write(struct uart_port *port, struct circ_buf *xmit)
59 {
60 while (!uart_circ_empty(xmit)) {
61 unsigned long ra = __pa(xmit->buf + xmit->tail);
62 unsigned long len, status, sent;
63
64 len = CIRC_CNT_TO_END(xmit->head, xmit->tail,
65 UART_XMIT_SIZE);
66 status = sun4v_con_write(ra, len, &sent);
67 if (status != HV_EOK)
68 break;
69 xmit->tail = (xmit->tail + sent) & (UART_XMIT_SIZE - 1);
70 port->icount.tx += sent;
71 }
72 }
73
74 static int receive_chars_getchar(struct uart_port *port)
75 {
76 int saw_console_brk = 0;
77 int limit = 10000;
78
79 while (limit-- > 0) {
80 long status;
81 long c = sun4v_con_getchar(&status);
82
83 if (status == HV_EWOULDBLOCK)
84 break;
85
86 if (c == CON_BREAK) {
87 if (uart_handle_break(port))
88 continue;
89 saw_console_brk = 1;
90 c = 0;
91 }
92
93 if (c == CON_HUP) {
94 hung_up = 1;
95 uart_handle_dcd_change(port, 0);
96 } else if (hung_up) {
97 hung_up = 0;
98 uart_handle_dcd_change(port, 1);
99 }
100
101 if (port->state == NULL) {
102 uart_handle_sysrq_char(port, c);
103 continue;
104 }
105
106 port->icount.rx++;
107
108 if (uart_handle_sysrq_char(port, c))
109 continue;
110
111 tty_insert_flip_char(&port->state->port, c, TTY_NORMAL);
112 }
113
114 return saw_console_brk;
115 }
116
117 static int receive_chars_read(struct uart_port *port)
118 {
119 int saw_console_brk = 0;
120 int limit = 10000;
121
122 while (limit-- > 0) {
123 unsigned long ra = __pa(con_read_page);
124 unsigned long bytes_read, i;
125 long stat = sun4v_con_read(ra, PAGE_SIZE, &bytes_read);
126
127 if (stat != HV_EOK) {
128 bytes_read = 0;
129
130 if (stat == CON_BREAK) {
131 if (uart_handle_break(port))
132 continue;
133 saw_console_brk = 1;
134 *con_read_page = 0;
135 bytes_read = 1;
136 } else if (stat == CON_HUP) {
137 hung_up = 1;
138 uart_handle_dcd_change(port, 0);
139 continue;
140 } else {
141 /* HV_EWOULDBLOCK, etc. */
142 break;
143 }
144 }
145
146 if (hung_up) {
147 hung_up = 0;
148 uart_handle_dcd_change(port, 1);
149 }
150
151 if (port->sysrq != 0 && *con_read_page) {
152 for (i = 0; i < bytes_read; i++)
153 uart_handle_sysrq_char(port, con_read_page[i]);
154 }
155
156 if (port->state == NULL)
157 continue;
158
159 port->icount.rx += bytes_read;
160
161 tty_insert_flip_string(&port->state->port, con_read_page,
162 bytes_read);
163 }
164
165 return saw_console_brk;
166 }
167
168 struct sunhv_ops {
169 void (*transmit_chars)(struct uart_port *port, struct circ_buf *xmit);
170 int (*receive_chars)(struct uart_port *port);
171 };
172
173 static const struct sunhv_ops bychar_ops = {
174 .transmit_chars = transmit_chars_putchar,
175 .receive_chars = receive_chars_getchar,
176 };
177
178 static const struct sunhv_ops bywrite_ops = {
179 .transmit_chars = transmit_chars_write,
180 .receive_chars = receive_chars_read,
181 };
182
183 static const struct sunhv_ops *sunhv_ops = &bychar_ops;
184
185 static struct tty_port *receive_chars(struct uart_port *port)
186 {
187 struct tty_port *tport = NULL;
188
189 if (port->state != NULL) /* Unopened serial console */
190 tport = &port->state->port;
191
192 if (sunhv_ops->receive_chars(port))
193 sun_do_break();
194
195 return tport;
196 }
197
198 static void transmit_chars(struct uart_port *port)
199 {
200 struct circ_buf *xmit;
201
202 if (!port->state)
203 return;
204
205 xmit = &port->state->xmit;
206 if (uart_circ_empty(xmit) || uart_tx_stopped(port))
207 return;
208
209 sunhv_ops->transmit_chars(port, xmit);
210
211 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
212 uart_write_wakeup(port);
213 }
214
215 static irqreturn_t sunhv_interrupt(int irq, void *dev_id)
216 {
217 struct uart_port *port = dev_id;
218 struct tty_port *tport;
219 unsigned long flags;
220
221 spin_lock_irqsave(&port->lock, flags);
222 tport = receive_chars(port);
223 transmit_chars(port);
224 spin_unlock_irqrestore(&port->lock, flags);
225
226 if (tport)
227 tty_flip_buffer_push(tport);
228
229 return IRQ_HANDLED;
230 }
231
232 /* port->lock is not held. */
233 static unsigned int sunhv_tx_empty(struct uart_port *port)
234 {
235 /* Transmitter is always empty for us. If the circ buffer
236 * is non-empty or there is an x_char pending, our caller
237 * will do the right thing and ignore what we return here.
238 */
239 return TIOCSER_TEMT;
240 }
241
242 /* port->lock held by caller. */
243 static void sunhv_set_mctrl(struct uart_port *port, unsigned int mctrl)
244 {
245 return;
246 }
247
248 /* port->lock is held by caller and interrupts are disabled. */
249 static unsigned int sunhv_get_mctrl(struct uart_port *port)
250 {
251 return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
252 }
253
254 /* port->lock held by caller. */
255 static void sunhv_stop_tx(struct uart_port *port)
256 {
257 return;
258 }
259
260 /* port->lock held by caller. */
261 static void sunhv_start_tx(struct uart_port *port)
262 {
263 transmit_chars(port);
264 }
265
266 /* port->lock is not held. */
267 static void sunhv_send_xchar(struct uart_port *port, char ch)
268 {
269 unsigned long flags;
270 int limit = 10000;
271
272 if (ch == __DISABLED_CHAR)
273 return;
274
275 spin_lock_irqsave(&port->lock, flags);
276
277 while (limit-- > 0) {
278 long status = sun4v_con_putchar(ch);
279 if (status == HV_EOK)
280 break;
281 udelay(1);
282 }
283
284 spin_unlock_irqrestore(&port->lock, flags);
285 }
286
287 /* port->lock held by caller. */
288 static void sunhv_stop_rx(struct uart_port *port)
289 {
290 }
291
292 /* port->lock is not held. */
293 static void sunhv_break_ctl(struct uart_port *port, int break_state)
294 {
295 if (break_state) {
296 unsigned long flags;
297 int limit = 10000;
298
299 spin_lock_irqsave(&port->lock, flags);
300
301 while (limit-- > 0) {
302 long status = sun4v_con_putchar(CON_BREAK);
303 if (status == HV_EOK)
304 break;
305 udelay(1);
306 }
307
308 spin_unlock_irqrestore(&port->lock, flags);
309 }
310 }
311
312 /* port->lock is not held. */
313 static int sunhv_startup(struct uart_port *port)
314 {
315 return 0;
316 }
317
318 /* port->lock is not held. */
319 static void sunhv_shutdown(struct uart_port *port)
320 {
321 }
322
323 /* port->lock is not held. */
324 static void sunhv_set_termios(struct uart_port *port, struct ktermios *termios,
325 struct ktermios *old)
326 {
327 unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
328 unsigned int quot = uart_get_divisor(port, baud);
329 unsigned int iflag, cflag;
330 unsigned long flags;
331
332 spin_lock_irqsave(&port->lock, flags);
333
334 iflag = termios->c_iflag;
335 cflag = termios->c_cflag;
336
337 port->ignore_status_mask = 0;
338 if (iflag & IGNBRK)
339 port->ignore_status_mask |= IGNORE_BREAK;
340 if ((cflag & CREAD) == 0)
341 port->ignore_status_mask |= IGNORE_ALL;
342
343 /* XXX */
344 uart_update_timeout(port, cflag,
345 (port->uartclk / (16 * quot)));
346
347 spin_unlock_irqrestore(&port->lock, flags);
348 }
349
350 static const char *sunhv_type(struct uart_port *port)
351 {
352 return "SUN4V HCONS";
353 }
354
355 static void sunhv_release_port(struct uart_port *port)
356 {
357 }
358
359 static int sunhv_request_port(struct uart_port *port)
360 {
361 return 0;
362 }
363
364 static void sunhv_config_port(struct uart_port *port, int flags)
365 {
366 }
367
368 static int sunhv_verify_port(struct uart_port *port, struct serial_struct *ser)
369 {
370 return -EINVAL;
371 }
372
373 static struct uart_ops sunhv_pops = {
374 .tx_empty = sunhv_tx_empty,
375 .set_mctrl = sunhv_set_mctrl,
376 .get_mctrl = sunhv_get_mctrl,
377 .stop_tx = sunhv_stop_tx,
378 .start_tx = sunhv_start_tx,
379 .send_xchar = sunhv_send_xchar,
380 .stop_rx = sunhv_stop_rx,
381 .break_ctl = sunhv_break_ctl,
382 .startup = sunhv_startup,
383 .shutdown = sunhv_shutdown,
384 .set_termios = sunhv_set_termios,
385 .type = sunhv_type,
386 .release_port = sunhv_release_port,
387 .request_port = sunhv_request_port,
388 .config_port = sunhv_config_port,
389 .verify_port = sunhv_verify_port,
390 };
391
392 static struct uart_driver sunhv_reg = {
393 .owner = THIS_MODULE,
394 .driver_name = "sunhv",
395 .dev_name = "ttyS",
396 .major = TTY_MAJOR,
397 };
398
399 static struct uart_port *sunhv_port;
400
401 /* Copy 's' into the con_write_page, decoding "\n" into
402 * "\r\n" along the way. We have to return two lengths
403 * because the caller needs to know how much to advance
404 * 's' and also how many bytes to output via con_write_page.
405 */
406 static int fill_con_write_page(const char *s, unsigned int n,
407 unsigned long *page_bytes)
408 {
409 const char *orig_s = s;
410 char *p = con_write_page;
411 int left = PAGE_SIZE;
412
413 while (n--) {
414 if (*s == '\n') {
415 if (left < 2)
416 break;
417 *p++ = '\r';
418 left--;
419 } else if (left < 1)
420 break;
421 *p++ = *s++;
422 left--;
423 }
424 *page_bytes = p - con_write_page;
425 return s - orig_s;
426 }
427
428 static void sunhv_console_write_paged(struct console *con, const char *s, unsigned n)
429 {
430 struct uart_port *port = sunhv_port;
431 unsigned long flags;
432 int locked = 1;
433
434 if (port->sysrq || oops_in_progress)
435 locked = spin_trylock_irqsave(&port->lock, flags);
436 else
437 spin_lock_irqsave(&port->lock, flags);
438
439 while (n > 0) {
440 unsigned long ra = __pa(con_write_page);
441 unsigned long page_bytes;
442 unsigned int cpy = fill_con_write_page(s, n,
443 &page_bytes);
444
445 n -= cpy;
446 s += cpy;
447 while (page_bytes > 0) {
448 unsigned long written;
449 int limit = 1000000;
450
451 while (limit--) {
452 unsigned long stat;
453
454 stat = sun4v_con_write(ra, page_bytes,
455 &written);
456 if (stat == HV_EOK)
457 break;
458 udelay(1);
459 }
460 if (limit < 0)
461 break;
462 page_bytes -= written;
463 ra += written;
464 }
465 }
466
467 if (locked)
468 spin_unlock_irqrestore(&port->lock, flags);
469 }
470
471 static inline void sunhv_console_putchar(struct uart_port *port, char c)
472 {
473 int limit = 1000000;
474
475 while (limit-- > 0) {
476 long status = sun4v_con_putchar(c);
477 if (status == HV_EOK)
478 break;
479 udelay(1);
480 }
481 }
482
483 static void sunhv_console_write_bychar(struct console *con, const char *s, unsigned n)
484 {
485 struct uart_port *port = sunhv_port;
486 unsigned long flags;
487 int i, locked = 1;
488
489 if (port->sysrq || oops_in_progress)
490 locked = spin_trylock_irqsave(&port->lock, flags);
491 else
492 spin_lock_irqsave(&port->lock, flags);
493
494 for (i = 0; i < n; i++) {
495 if (*s == '\n')
496 sunhv_console_putchar(port, '\r');
497 sunhv_console_putchar(port, *s++);
498 }
499
500 if (locked)
501 spin_unlock_irqrestore(&port->lock, flags);
502 }
503
504 static struct console sunhv_console = {
505 .name = "ttyHV",
506 .write = sunhv_console_write_bychar,
507 .device = uart_console_device,
508 .flags = CON_PRINTBUFFER,
509 .index = -1,
510 .data = &sunhv_reg,
511 };
512
513 static int hv_probe(struct platform_device *op)
514 {
515 struct uart_port *port;
516 unsigned long minor;
517 int err;
518
519 if (op->archdata.irqs[0] == 0xffffffff)
520 return -ENODEV;
521
522 port = kzalloc(sizeof(struct uart_port), GFP_KERNEL);
523 if (unlikely(!port))
524 return -ENOMEM;
525
526 minor = 1;
527 if (sun4v_hvapi_register(HV_GRP_CORE, 1, &minor) == 0 &&
528 minor >= 1) {
529 err = -ENOMEM;
530 con_write_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
531 if (!con_write_page)
532 goto out_free_port;
533
534 con_read_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
535 if (!con_read_page)
536 goto out_free_con_write_page;
537
538 sunhv_console.write = sunhv_console_write_paged;
539 sunhv_ops = &bywrite_ops;
540 }
541
542 sunhv_port = port;
543
544 port->line = 0;
545 port->ops = &sunhv_pops;
546 port->type = PORT_SUNHV;
547 port->uartclk = ( 29491200 / 16 ); /* arbitrary */
548
549 port->membase = (unsigned char __iomem *) __pa(port);
550
551 port->irq = op->archdata.irqs[0];
552
553 port->dev = &op->dev;
554
555 err = sunserial_register_minors(&sunhv_reg, 1);
556 if (err)
557 goto out_free_con_read_page;
558
559 sunserial_console_match(&sunhv_console, op->dev.of_node,
560 &sunhv_reg, port->line, false);
561
562 err = uart_add_one_port(&sunhv_reg, port);
563 if (err)
564 goto out_unregister_driver;
565
566 err = request_irq(port->irq, sunhv_interrupt, 0, "hvcons", port);
567 if (err)
568 goto out_remove_port;
569
570 platform_set_drvdata(op, port);
571
572 return 0;
573
574 out_remove_port:
575 uart_remove_one_port(&sunhv_reg, port);
576
577 out_unregister_driver:
578 sunserial_unregister_minors(&sunhv_reg, 1);
579
580 out_free_con_read_page:
581 kfree(con_read_page);
582
583 out_free_con_write_page:
584 kfree(con_write_page);
585
586 out_free_port:
587 kfree(port);
588 sunhv_port = NULL;
589 return err;
590 }
591
592 static int hv_remove(struct platform_device *dev)
593 {
594 struct uart_port *port = platform_get_drvdata(dev);
595
596 free_irq(port->irq, port);
597
598 uart_remove_one_port(&sunhv_reg, port);
599
600 sunserial_unregister_minors(&sunhv_reg, 1);
601 kfree(con_read_page);
602 kfree(con_write_page);
603 kfree(port);
604 sunhv_port = NULL;
605
606 return 0;
607 }
608
609 static const struct of_device_id hv_match[] = {
610 {
611 .name = "console",
612 .compatible = "qcn",
613 },
614 {
615 .name = "console",
616 .compatible = "SUNW,sun4v-console",
617 },
618 {},
619 };
620
621 static struct platform_driver hv_driver = {
622 .driver = {
623 .name = "hv",
624 .of_match_table = hv_match,
625 },
626 .probe = hv_probe,
627 .remove = hv_remove,
628 };
629
630 static int __init sunhv_init(void)
631 {
632 if (tlb_type != hypervisor)
633 return -ENODEV;
634
635 return platform_driver_register(&hv_driver);
636 }
637 device_initcall(sunhv_init);
638
639 #if 0 /* ...def MODULE ; never supported as such */
640 MODULE_AUTHOR("David S. Miller");
641 MODULE_DESCRIPTION("SUN4V Hypervisor console driver");
642 MODULE_VERSION("2.0");
643 MODULE_LICENSE("GPL");
644 #endif
Linux with added FPC-III support