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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/module.h>
7#include <linux/kernel.h>
8#include <linux/errno.h>
9#include <linux/tty.h>
10#include <linux/tty_flip.h>
11#include <linux/major.h>
12#include <linux/circ_buf.h>
13#include <linux/serial.h>
14#include <linux/sysrq.h>
15#include <linux/console.h>
16#include <linux/spinlock.h>
17#include <linux/slab.h>
18#include <linux/delay.h>
19#include <linux/init.h>
20#include <linux/of_device.h>
21
22#include <asm/hypervisor.h>
23#include <asm/spitfire.h>
24#include <asm/prom.h>
25#include <asm/irq.h>
26
27#if defined(CONFIG_MAGIC_SYSRQ)
28#define SUPPORT_SYSRQ
29#endif
30
31#include <linux/serial_core.h>
32
33#include "suncore.h"
34
35#define CON_BREAK ((long)-1)
36#define CON_HUP ((long)-2)
37
38#define IGNORE_BREAK 0x1
39#define IGNORE_ALL 0x2
40
41static char *con_write_page;
42static char *con_read_page;
43
44static int hung_up = 0;
45
46static void transmit_chars_putchar(struct uart_port *port, struct circ_buf *xmit)
47{
48 while (!uart_circ_empty(xmit)) {
49 long status = sun4v_con_putchar(xmit->buf[xmit->tail]);
50
51 if (status != HV_EOK)
52 break;
53
54 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
55 port->icount.tx++;
56 }
57}
58
59static void transmit_chars_write(struct uart_port *port, struct circ_buf *xmit)
60{
61 while (!uart_circ_empty(xmit)) {
62 unsigned long ra = __pa(xmit->buf + xmit->tail);
63 unsigned long len, status, sent;
64
65 len = CIRC_CNT_TO_END(xmit->head, xmit->tail,
66 UART_XMIT_SIZE);
67 status = sun4v_con_write(ra, len, &sent);
68 if (status != HV_EOK)
69 break;
70 xmit->tail = (xmit->tail + sent) & (UART_XMIT_SIZE - 1);
71 port->icount.tx += sent;
72 }
73}
74
75static int receive_chars_getchar(struct uart_port *port, struct tty_struct *tty)
76{
77 int saw_console_brk = 0;
78 int limit = 10000;
79
80 while (limit-- > 0) {
81 long status;
82 long c = sun4v_con_getchar(&status);
83
84 if (status == HV_EWOULDBLOCK)
85 break;
86
87 if (c == CON_BREAK) {
88 if (uart_handle_break(port))
89 continue;
90 saw_console_brk = 1;
91 c = 0;
92 }
93
94 if (c == CON_HUP) {
95 hung_up = 1;
96 uart_handle_dcd_change(port, 0);
97 } else if (hung_up) {
98 hung_up = 0;
99 uart_handle_dcd_change(port, 1);
100 }
101
102 if (tty == NULL) {
103 uart_handle_sysrq_char(port, c);
104 continue;
105 }
106
107 port->icount.rx++;
108
109 if (uart_handle_sysrq_char(port, c))
110 continue;
111
112 tty_insert_flip_char(tty, c, TTY_NORMAL);
113 }
114
115 return saw_console_brk;
116}
117
118static int receive_chars_read(struct uart_port *port, struct tty_struct *tty)
119{
120 int saw_console_brk = 0;
121 int limit = 10000;
122
123 while (limit-- > 0) {
124 unsigned long ra = __pa(con_read_page);
125 unsigned long bytes_read, i;
126 long stat = sun4v_con_read(ra, PAGE_SIZE, &bytes_read);
127
128 if (stat != HV_EOK) {
129 bytes_read = 0;
130
131 if (stat == CON_BREAK) {
132 if (uart_handle_break(port))
133 continue;
134 saw_console_brk = 1;
135 *con_read_page = 0;
136 bytes_read = 1;
137 } else if (stat == CON_HUP) {
138 hung_up = 1;
139 uart_handle_dcd_change(port, 0);
140 continue;
141 } else {
142 /* HV_EWOULDBLOCK, etc. */
143 break;
144 }
145 }
146
147 if (hung_up) {
148 hung_up = 0;
149 uart_handle_dcd_change(port, 1);
150 }
151
152 for (i = 0; i < bytes_read; i++)
153 uart_handle_sysrq_char(port, con_read_page[i]);
154
155 if (tty == NULL)
156 continue;
157
158 port->icount.rx += bytes_read;
159
160 tty_insert_flip_string(tty, con_read_page, bytes_read);
161 }
162
163 return saw_console_brk;
164}
165
166struct sunhv_ops {
167 void (*transmit_chars)(struct uart_port *port, struct circ_buf *xmit);
168 int (*receive_chars)(struct uart_port *port, struct tty_struct *tty);
169};
170
171static struct sunhv_ops bychar_ops = {
172 .transmit_chars = transmit_chars_putchar,
173 .receive_chars = receive_chars_getchar,
174};
175
176static struct sunhv_ops bywrite_ops = {
177 .transmit_chars = transmit_chars_write,
178 .receive_chars = receive_chars_read,
179};
180
181static struct sunhv_ops *sunhv_ops = &bychar_ops;
182
183static struct tty_struct *receive_chars(struct uart_port *port)
184{
185 struct tty_struct *tty = NULL;
186
187 if (port->state != NULL) /* Unopened serial console */
188 tty = port->state->port.tty;
189
190 if (sunhv_ops->receive_chars(port, tty))
191 sun_do_break();
192
193 return tty;
194}
195
196static void transmit_chars(struct uart_port *port)
197{
198 struct circ_buf *xmit;
199
200 if (!port->state)
201 return;
202
203 xmit = &port->state->xmit;
204 if (uart_circ_empty(xmit) || uart_tx_stopped(port))
205 return;
206
207 sunhv_ops->transmit_chars(port, xmit);
208
209 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
210 uart_write_wakeup(port);
211}
212
213static irqreturn_t sunhv_interrupt(int irq, void *dev_id)
214{
215 struct uart_port *port = dev_id;
216 struct tty_struct *tty;
217 unsigned long flags;
218
219 spin_lock_irqsave(&port->lock, flags);
220 tty = receive_chars(port);
221 transmit_chars(port);
222 spin_unlock_irqrestore(&port->lock, flags);
223
224 if (tty)
225 tty_flip_buffer_push(tty);
226
227 return IRQ_HANDLED;
228}
229
230/* port->lock is not held. */
231static unsigned int sunhv_tx_empty(struct uart_port *port)
232{
233 /* Transmitter is always empty for us. If the circ buffer
234 * is non-empty or there is an x_char pending, our caller
235 * will do the right thing and ignore what we return here.
236 */
237 return TIOCSER_TEMT;
238}
239
240/* port->lock held by caller. */
241static void sunhv_set_mctrl(struct uart_port *port, unsigned int mctrl)
242{
243 return;
244}
245
246/* port->lock is held by caller and interrupts are disabled. */
247static unsigned int sunhv_get_mctrl(struct uart_port *port)
248{
249 return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
250}
251
252/* port->lock held by caller. */
253static void sunhv_stop_tx(struct uart_port *port)
254{
255 return;
256}
257
258/* port->lock held by caller. */
259static void sunhv_start_tx(struct uart_port *port)
260{
261 transmit_chars(port);
262}
263
264/* port->lock is not held. */
265static void sunhv_send_xchar(struct uart_port *port, char ch)
266{
267 unsigned long flags;
268 int limit = 10000;
269
270 spin_lock_irqsave(&port->lock, flags);
271
272 while (limit-- > 0) {
273 long status = sun4v_con_putchar(ch);
274 if (status == HV_EOK)
275 break;
276 udelay(1);
277 }
278
279 spin_unlock_irqrestore(&port->lock, flags);
280}
281
282/* port->lock held by caller. */
283static void sunhv_stop_rx(struct uart_port *port)
284{
285}
286
287/* port->lock held by caller. */
288static void sunhv_enable_ms(struct uart_port *port)
289{
290}
291
292/* port->lock is not held. */
293static 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. */
313static int sunhv_startup(struct uart_port *port)
314{
315 return 0;
316}
317
318/* port->lock is not held. */
319static void sunhv_shutdown(struct uart_port *port)
320{
321}
322
323/* port->lock is not held. */
324static 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
350static const char *sunhv_type(struct uart_port *port)
351{
352 return "SUN4V HCONS";
353}
354
355static void sunhv_release_port(struct uart_port *port)
356{
357}
358
359static int sunhv_request_port(struct uart_port *port)
360{
361 return 0;
362}
363
364static void sunhv_config_port(struct uart_port *port, int flags)
365{
366}
367
368static int sunhv_verify_port(struct uart_port *port, struct serial_struct *ser)
369{
370 return -EINVAL;
371}
372
373static 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 .enable_ms = sunhv_enable_ms,
382 .break_ctl = sunhv_break_ctl,
383 .startup = sunhv_startup,
384 .shutdown = sunhv_shutdown,
385 .set_termios = sunhv_set_termios,
386 .type = sunhv_type,
387 .release_port = sunhv_release_port,
388 .request_port = sunhv_request_port,
389 .config_port = sunhv_config_port,
390 .verify_port = sunhv_verify_port,
391};
392
393static struct uart_driver sunhv_reg = {
394 .owner = THIS_MODULE,
395 .driver_name = "sunhv",
396 .dev_name = "ttyS",
397 .major = TTY_MAJOR,
398};
399
400static struct uart_port *sunhv_port;
401
402/* Copy 's' into the con_write_page, decoding "\n" into
403 * "\r\n" along the way. We have to return two lengths
404 * because the caller needs to know how much to advance
405 * 's' and also how many bytes to output via con_write_page.
406 */
407static int fill_con_write_page(const char *s, unsigned int n,
408 unsigned long *page_bytes)
409{
410 const char *orig_s = s;
411 char *p = con_write_page;
412 int left = PAGE_SIZE;
413
414 while (n--) {
415 if (*s == '\n') {
416 if (left < 2)
417 break;
418 *p++ = '\r';
419 left--;
420 } else if (left < 1)
421 break;
422 *p++ = *s++;
423 left--;
424 }
425 *page_bytes = p - con_write_page;
426 return s - orig_s;
427}
428
429static void sunhv_console_write_paged(struct console *con, const char *s, unsigned n)
430{
431 struct uart_port *port = sunhv_port;
432 unsigned long flags;
433 int locked = 1;
434
435 local_irq_save(flags);
436 if (port->sysrq) {
437 locked = 0;
438 } else if (oops_in_progress) {
439 locked = spin_trylock(&port->lock);
440 } else
441 spin_lock(&port->lock);
442
443 while (n > 0) {
444 unsigned long ra = __pa(con_write_page);
445 unsigned long page_bytes;
446 unsigned int cpy = fill_con_write_page(s, n,
447 &page_bytes);
448
449 n -= cpy;
450 s += cpy;
451 while (page_bytes > 0) {
452 unsigned long written;
453 int limit = 1000000;
454
455 while (limit--) {
456 unsigned long stat;
457
458 stat = sun4v_con_write(ra, page_bytes,
459 &written);
460 if (stat == HV_EOK)
461 break;
462 udelay(1);
463 }
464 if (limit < 0)
465 break;
466 page_bytes -= written;
467 ra += written;
468 }
469 }
470
471 if (locked)
472 spin_unlock(&port->lock);
473 local_irq_restore(flags);
474}
475
476static inline void sunhv_console_putchar(struct uart_port *port, char c)
477{
478 int limit = 1000000;
479
480 while (limit-- > 0) {
481 long status = sun4v_con_putchar(c);
482 if (status == HV_EOK)
483 break;
484 udelay(1);
485 }
486}
487
488static void sunhv_console_write_bychar(struct console *con, const char *s, unsigned n)
489{
490 struct uart_port *port = sunhv_port;
491 unsigned long flags;
492 int i, locked = 1;
493
494 local_irq_save(flags);
495 if (port->sysrq) {
496 locked = 0;
497 } else if (oops_in_progress) {
498 locked = spin_trylock(&port->lock);
499 } else
500 spin_lock(&port->lock);
501
502 for (i = 0; i < n; i++) {
503 if (*s == '\n')
504 sunhv_console_putchar(port, '\r');
505 sunhv_console_putchar(port, *s++);
506 }
507
508 if (locked)
509 spin_unlock(&port->lock);
510 local_irq_restore(flags);
511}
512
513static struct console sunhv_console = {
514 .name = "ttyHV",
515 .write = sunhv_console_write_bychar,
516 .device = uart_console_device,
517 .flags = CON_PRINTBUFFER,
518 .index = -1,
519 .data = &sunhv_reg,
520};
521
522static int __devinit hv_probe(struct platform_device *op)
523{
524 struct uart_port *port;
525 unsigned long minor;
526 int err;
527
528 if (op->archdata.irqs[0] == 0xffffffff)
529 return -ENODEV;
530
531 port = kzalloc(sizeof(struct uart_port), GFP_KERNEL);
532 if (unlikely(!port))
533 return -ENOMEM;
534
535 minor = 1;
536 if (sun4v_hvapi_register(HV_GRP_CORE, 1, &minor) == 0 &&
537 minor >= 1) {
538 err = -ENOMEM;
539 con_write_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
540 if (!con_write_page)
541 goto out_free_port;
542
543 con_read_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
544 if (!con_read_page)
545 goto out_free_con_write_page;
546
547 sunhv_console.write = sunhv_console_write_paged;
548 sunhv_ops = &bywrite_ops;
549 }
550
551 sunhv_port = port;
552
553 port->line = 0;
554 port->ops = &sunhv_pops;
555 port->type = PORT_SUNHV;
556 port->uartclk = ( 29491200 / 16 ); /* arbitrary */
557
558 port->membase = (unsigned char __iomem *) __pa(port);
559
560 port->irq = op->archdata.irqs[0];
561
562 port->dev = &op->dev;
563
564 err = sunserial_register_minors(&sunhv_reg, 1);
565 if (err)
566 goto out_free_con_read_page;
567
568 sunserial_console_match(&sunhv_console, op->dev.of_node,
569 &sunhv_reg, port->line, false);
570
571 err = uart_add_one_port(&sunhv_reg, port);
572 if (err)
573 goto out_unregister_driver;
574
575 err = request_irq(port->irq, sunhv_interrupt, 0, "hvcons", port);
576 if (err)
577 goto out_remove_port;
578
579 dev_set_drvdata(&op->dev, port);
580
581 return 0;
582
583out_remove_port:
584 uart_remove_one_port(&sunhv_reg, port);
585
586out_unregister_driver:
587 sunserial_unregister_minors(&sunhv_reg, 1);
588
589out_free_con_read_page:
590 kfree(con_read_page);
591
592out_free_con_write_page:
593 kfree(con_write_page);
594
595out_free_port:
596 kfree(port);
597 sunhv_port = NULL;
598 return err;
599}
600
601static int __devexit hv_remove(struct platform_device *dev)
602{
603 struct uart_port *port = dev_get_drvdata(&dev->dev);
604
605 free_irq(port->irq, port);
606
607 uart_remove_one_port(&sunhv_reg, port);
608
609 sunserial_unregister_minors(&sunhv_reg, 1);
610
611 kfree(port);
612 sunhv_port = NULL;
613
614 dev_set_drvdata(&dev->dev, NULL);
615
616 return 0;
617}
618
619static const struct of_device_id hv_match[] = {
620 {
621 .name = "console",
622 .compatible = "qcn",
623 },
624 {
625 .name = "console",
626 .compatible = "SUNW,sun4v-console",
627 },
628 {},
629};
630MODULE_DEVICE_TABLE(of, hv_match);
631
632static struct platform_driver hv_driver = {
633 .driver = {
634 .name = "hv",
635 .owner = THIS_MODULE,
636 .of_match_table = hv_match,
637 },
638 .probe = hv_probe,
639 .remove = __devexit_p(hv_remove),
640};
641
642static int __init sunhv_init(void)
643{
644 if (tlb_type != hypervisor)
645 return -ENODEV;
646
647 return platform_driver_register(&hv_driver);
648}
649
650static void __exit sunhv_exit(void)
651{
652 platform_driver_unregister(&hv_driver);
653}
654
655module_init(sunhv_init);
656module_exit(sunhv_exit);
657
658MODULE_AUTHOR("David S. Miller");
659MODULE_DESCRIPTION("SUN4V Hypervisor console driver");
660MODULE_VERSION("2.0");
661MODULE_LICENSE("GPL");
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/module.h>
7#include <linux/kernel.h>
8#include <linux/errno.h>
9#include <linux/tty.h>
10#include <linux/tty_flip.h>
11#include <linux/major.h>
12#include <linux/circ_buf.h>
13#include <linux/serial.h>
14#include <linux/sysrq.h>
15#include <linux/console.h>
16#include <linux/spinlock.h>
17#include <linux/slab.h>
18#include <linux/delay.h>
19#include <linux/init.h>
20#include <linux/of_device.h>
21
22#include <asm/hypervisor.h>
23#include <asm/spitfire.h>
24#include <asm/prom.h>
25#include <asm/irq.h>
26#include <asm/setup.h>
27
28#if defined(CONFIG_MAGIC_SYSRQ)
29#define SUPPORT_SYSRQ
30#endif
31
32#include <linux/serial_core.h>
33#include <linux/sunserialcore.h>
34
35#define CON_BREAK ((long)-1)
36#define CON_HUP ((long)-2)
37
38#define IGNORE_BREAK 0x1
39#define IGNORE_ALL 0x2
40
41static char *con_write_page;
42static char *con_read_page;
43
44static int hung_up = 0;
45
46static void transmit_chars_putchar(struct uart_port *port, struct circ_buf *xmit)
47{
48 while (!uart_circ_empty(xmit)) {
49 long status = sun4v_con_putchar(xmit->buf[xmit->tail]);
50
51 if (status != HV_EOK)
52 break;
53
54 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
55 port->icount.tx++;
56 }
57}
58
59static void transmit_chars_write(struct uart_port *port, struct circ_buf *xmit)
60{
61 while (!uart_circ_empty(xmit)) {
62 unsigned long ra = __pa(xmit->buf + xmit->tail);
63 unsigned long len, status, sent;
64
65 len = CIRC_CNT_TO_END(xmit->head, xmit->tail,
66 UART_XMIT_SIZE);
67 status = sun4v_con_write(ra, len, &sent);
68 if (status != HV_EOK)
69 break;
70 xmit->tail = (xmit->tail + sent) & (UART_XMIT_SIZE - 1);
71 port->icount.tx += sent;
72 }
73}
74
75static int receive_chars_getchar(struct uart_port *port)
76{
77 int saw_console_brk = 0;
78 int limit = 10000;
79
80 while (limit-- > 0) {
81 long status;
82 long c = sun4v_con_getchar(&status);
83
84 if (status == HV_EWOULDBLOCK)
85 break;
86
87 if (c == CON_BREAK) {
88 if (uart_handle_break(port))
89 continue;
90 saw_console_brk = 1;
91 c = 0;
92 }
93
94 if (c == CON_HUP) {
95 hung_up = 1;
96 uart_handle_dcd_change(port, 0);
97 } else if (hung_up) {
98 hung_up = 0;
99 uart_handle_dcd_change(port, 1);
100 }
101
102 if (port->state == NULL) {
103 uart_handle_sysrq_char(port, c);
104 continue;
105 }
106
107 port->icount.rx++;
108
109 if (uart_handle_sysrq_char(port, c))
110 continue;
111
112 tty_insert_flip_char(&port->state->port, c, TTY_NORMAL);
113 }
114
115 return saw_console_brk;
116}
117
118static int receive_chars_read(struct uart_port *port)
119{
120 int saw_console_brk = 0;
121 int limit = 10000;
122
123 while (limit-- > 0) {
124 unsigned long ra = __pa(con_read_page);
125 unsigned long bytes_read, i;
126 long stat = sun4v_con_read(ra, PAGE_SIZE, &bytes_read);
127
128 if (stat != HV_EOK) {
129 bytes_read = 0;
130
131 if (stat == CON_BREAK) {
132 if (uart_handle_break(port))
133 continue;
134 saw_console_brk = 1;
135 *con_read_page = 0;
136 bytes_read = 1;
137 } else if (stat == CON_HUP) {
138 hung_up = 1;
139 uart_handle_dcd_change(port, 0);
140 continue;
141 } else {
142 /* HV_EWOULDBLOCK, etc. */
143 break;
144 }
145 }
146
147 if (hung_up) {
148 hung_up = 0;
149 uart_handle_dcd_change(port, 1);
150 }
151
152 for (i = 0; i < bytes_read; i++)
153 uart_handle_sysrq_char(port, con_read_page[i]);
154
155 if (port->state == NULL)
156 continue;
157
158 port->icount.rx += bytes_read;
159
160 tty_insert_flip_string(&port->state->port, con_read_page,
161 bytes_read);
162 }
163
164 return saw_console_brk;
165}
166
167struct sunhv_ops {
168 void (*transmit_chars)(struct uart_port *port, struct circ_buf *xmit);
169 int (*receive_chars)(struct uart_port *port);
170};
171
172static struct sunhv_ops bychar_ops = {
173 .transmit_chars = transmit_chars_putchar,
174 .receive_chars = receive_chars_getchar,
175};
176
177static struct sunhv_ops bywrite_ops = {
178 .transmit_chars = transmit_chars_write,
179 .receive_chars = receive_chars_read,
180};
181
182static struct sunhv_ops *sunhv_ops = &bychar_ops;
183
184static struct tty_port *receive_chars(struct uart_port *port)
185{
186 struct tty_port *tport = NULL;
187
188 if (port->state != NULL) /* Unopened serial console */
189 tport = &port->state->port;
190
191 if (sunhv_ops->receive_chars(port))
192 sun_do_break();
193
194 return tport;
195}
196
197static void transmit_chars(struct uart_port *port)
198{
199 struct circ_buf *xmit;
200
201 if (!port->state)
202 return;
203
204 xmit = &port->state->xmit;
205 if (uart_circ_empty(xmit) || uart_tx_stopped(port))
206 return;
207
208 sunhv_ops->transmit_chars(port, xmit);
209
210 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
211 uart_write_wakeup(port);
212}
213
214static irqreturn_t sunhv_interrupt(int irq, void *dev_id)
215{
216 struct uart_port *port = dev_id;
217 struct tty_port *tport;
218 unsigned long flags;
219
220 spin_lock_irqsave(&port->lock, flags);
221 tport = receive_chars(port);
222 transmit_chars(port);
223 spin_unlock_irqrestore(&port->lock, flags);
224
225 if (tport)
226 tty_flip_buffer_push(tport);
227
228 return IRQ_HANDLED;
229}
230
231/* port->lock is not held. */
232static unsigned int sunhv_tx_empty(struct uart_port *port)
233{
234 /* Transmitter is always empty for us. If the circ buffer
235 * is non-empty or there is an x_char pending, our caller
236 * will do the right thing and ignore what we return here.
237 */
238 return TIOCSER_TEMT;
239}
240
241/* port->lock held by caller. */
242static void sunhv_set_mctrl(struct uart_port *port, unsigned int mctrl)
243{
244 return;
245}
246
247/* port->lock is held by caller and interrupts are disabled. */
248static unsigned int sunhv_get_mctrl(struct uart_port *port)
249{
250 return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
251}
252
253/* port->lock held by caller. */
254static void sunhv_stop_tx(struct uart_port *port)
255{
256 return;
257}
258
259/* port->lock held by caller. */
260static void sunhv_start_tx(struct uart_port *port)
261{
262 transmit_chars(port);
263}
264
265/* port->lock is not held. */
266static void sunhv_send_xchar(struct uart_port *port, char ch)
267{
268 unsigned long flags;
269 int limit = 10000;
270
271 spin_lock_irqsave(&port->lock, flags);
272
273 while (limit-- > 0) {
274 long status = sun4v_con_putchar(ch);
275 if (status == HV_EOK)
276 break;
277 udelay(1);
278 }
279
280 spin_unlock_irqrestore(&port->lock, flags);
281}
282
283/* port->lock held by caller. */
284static void sunhv_stop_rx(struct uart_port *port)
285{
286}
287
288/* port->lock held by caller. */
289static void sunhv_enable_ms(struct uart_port *port)
290{
291}
292
293/* port->lock is not held. */
294static void sunhv_break_ctl(struct uart_port *port, int break_state)
295{
296 if (break_state) {
297 unsigned long flags;
298 int limit = 10000;
299
300 spin_lock_irqsave(&port->lock, flags);
301
302 while (limit-- > 0) {
303 long status = sun4v_con_putchar(CON_BREAK);
304 if (status == HV_EOK)
305 break;
306 udelay(1);
307 }
308
309 spin_unlock_irqrestore(&port->lock, flags);
310 }
311}
312
313/* port->lock is not held. */
314static int sunhv_startup(struct uart_port *port)
315{
316 return 0;
317}
318
319/* port->lock is not held. */
320static void sunhv_shutdown(struct uart_port *port)
321{
322}
323
324/* port->lock is not held. */
325static void sunhv_set_termios(struct uart_port *port, struct ktermios *termios,
326 struct ktermios *old)
327{
328 unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
329 unsigned int quot = uart_get_divisor(port, baud);
330 unsigned int iflag, cflag;
331 unsigned long flags;
332
333 spin_lock_irqsave(&port->lock, flags);
334
335 iflag = termios->c_iflag;
336 cflag = termios->c_cflag;
337
338 port->ignore_status_mask = 0;
339 if (iflag & IGNBRK)
340 port->ignore_status_mask |= IGNORE_BREAK;
341 if ((cflag & CREAD) == 0)
342 port->ignore_status_mask |= IGNORE_ALL;
343
344 /* XXX */
345 uart_update_timeout(port, cflag,
346 (port->uartclk / (16 * quot)));
347
348 spin_unlock_irqrestore(&port->lock, flags);
349}
350
351static const char *sunhv_type(struct uart_port *port)
352{
353 return "SUN4V HCONS";
354}
355
356static void sunhv_release_port(struct uart_port *port)
357{
358}
359
360static int sunhv_request_port(struct uart_port *port)
361{
362 return 0;
363}
364
365static void sunhv_config_port(struct uart_port *port, int flags)
366{
367}
368
369static int sunhv_verify_port(struct uart_port *port, struct serial_struct *ser)
370{
371 return -EINVAL;
372}
373
374static struct uart_ops sunhv_pops = {
375 .tx_empty = sunhv_tx_empty,
376 .set_mctrl = sunhv_set_mctrl,
377 .get_mctrl = sunhv_get_mctrl,
378 .stop_tx = sunhv_stop_tx,
379 .start_tx = sunhv_start_tx,
380 .send_xchar = sunhv_send_xchar,
381 .stop_rx = sunhv_stop_rx,
382 .enable_ms = sunhv_enable_ms,
383 .break_ctl = sunhv_break_ctl,
384 .startup = sunhv_startup,
385 .shutdown = sunhv_shutdown,
386 .set_termios = sunhv_set_termios,
387 .type = sunhv_type,
388 .release_port = sunhv_release_port,
389 .request_port = sunhv_request_port,
390 .config_port = sunhv_config_port,
391 .verify_port = sunhv_verify_port,
392};
393
394static struct uart_driver sunhv_reg = {
395 .owner = THIS_MODULE,
396 .driver_name = "sunhv",
397 .dev_name = "ttyS",
398 .major = TTY_MAJOR,
399};
400
401static struct uart_port *sunhv_port;
402
403/* Copy 's' into the con_write_page, decoding "\n" into
404 * "\r\n" along the way. We have to return two lengths
405 * because the caller needs to know how much to advance
406 * 's' and also how many bytes to output via con_write_page.
407 */
408static int fill_con_write_page(const char *s, unsigned int n,
409 unsigned long *page_bytes)
410{
411 const char *orig_s = s;
412 char *p = con_write_page;
413 int left = PAGE_SIZE;
414
415 while (n--) {
416 if (*s == '\n') {
417 if (left < 2)
418 break;
419 *p++ = '\r';
420 left--;
421 } else if (left < 1)
422 break;
423 *p++ = *s++;
424 left--;
425 }
426 *page_bytes = p - con_write_page;
427 return s - orig_s;
428}
429
430static void sunhv_console_write_paged(struct console *con, const char *s, unsigned n)
431{
432 struct uart_port *port = sunhv_port;
433 unsigned long flags;
434 int locked = 1;
435
436 if (port->sysrq || oops_in_progress)
437 locked = spin_trylock_irqsave(&port->lock, flags);
438 else
439 spin_lock_irqsave(&port->lock, flags);
440
441 while (n > 0) {
442 unsigned long ra = __pa(con_write_page);
443 unsigned long page_bytes;
444 unsigned int cpy = fill_con_write_page(s, n,
445 &page_bytes);
446
447 n -= cpy;
448 s += cpy;
449 while (page_bytes > 0) {
450 unsigned long written;
451 int limit = 1000000;
452
453 while (limit--) {
454 unsigned long stat;
455
456 stat = sun4v_con_write(ra, page_bytes,
457 &written);
458 if (stat == HV_EOK)
459 break;
460 udelay(1);
461 }
462 if (limit < 0)
463 break;
464 page_bytes -= written;
465 ra += written;
466 }
467 }
468
469 if (locked)
470 spin_unlock_irqrestore(&port->lock, flags);
471}
472
473static inline void sunhv_console_putchar(struct uart_port *port, char c)
474{
475 int limit = 1000000;
476
477 while (limit-- > 0) {
478 long status = sun4v_con_putchar(c);
479 if (status == HV_EOK)
480 break;
481 udelay(1);
482 }
483}
484
485static void sunhv_console_write_bychar(struct console *con, const char *s, unsigned n)
486{
487 struct uart_port *port = sunhv_port;
488 unsigned long flags;
489 int i, locked = 1;
490
491 if (port->sysrq || oops_in_progress)
492 locked = spin_trylock_irqsave(&port->lock, flags);
493 else
494 spin_lock_irqsave(&port->lock, flags);
495 if (port->sysrq) {
496 locked = 0;
497 } else if (oops_in_progress) {
498 locked = spin_trylock(&port->lock);
499 } else
500 spin_lock(&port->lock);
501
502 for (i = 0; i < n; i++) {
503 if (*s == '\n')
504 sunhv_console_putchar(port, '\r');
505 sunhv_console_putchar(port, *s++);
506 }
507
508 if (locked)
509 spin_unlock_irqrestore(&port->lock, flags);
510}
511
512static struct console sunhv_console = {
513 .name = "ttyHV",
514 .write = sunhv_console_write_bychar,
515 .device = uart_console_device,
516 .flags = CON_PRINTBUFFER,
517 .index = -1,
518 .data = &sunhv_reg,
519};
520
521static int hv_probe(struct platform_device *op)
522{
523 struct uart_port *port;
524 unsigned long minor;
525 int err;
526
527 if (op->archdata.irqs[0] == 0xffffffff)
528 return -ENODEV;
529
530 port = kzalloc(sizeof(struct uart_port), GFP_KERNEL);
531 if (unlikely(!port))
532 return -ENOMEM;
533
534 minor = 1;
535 if (sun4v_hvapi_register(HV_GRP_CORE, 1, &minor) == 0 &&
536 minor >= 1) {
537 err = -ENOMEM;
538 con_write_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
539 if (!con_write_page)
540 goto out_free_port;
541
542 con_read_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
543 if (!con_read_page)
544 goto out_free_con_write_page;
545
546 sunhv_console.write = sunhv_console_write_paged;
547 sunhv_ops = &bywrite_ops;
548 }
549
550 sunhv_port = port;
551
552 port->line = 0;
553 port->ops = &sunhv_pops;
554 port->type = PORT_SUNHV;
555 port->uartclk = ( 29491200 / 16 ); /* arbitrary */
556
557 port->membase = (unsigned char __iomem *) __pa(port);
558
559 port->irq = op->archdata.irqs[0];
560
561 port->dev = &op->dev;
562
563 err = sunserial_register_minors(&sunhv_reg, 1);
564 if (err)
565 goto out_free_con_read_page;
566
567 sunserial_console_match(&sunhv_console, op->dev.of_node,
568 &sunhv_reg, port->line, false);
569
570 err = uart_add_one_port(&sunhv_reg, port);
571 if (err)
572 goto out_unregister_driver;
573
574 err = request_irq(port->irq, sunhv_interrupt, 0, "hvcons", port);
575 if (err)
576 goto out_remove_port;
577
578 platform_set_drvdata(op, port);
579
580 return 0;
581
582out_remove_port:
583 uart_remove_one_port(&sunhv_reg, port);
584
585out_unregister_driver:
586 sunserial_unregister_minors(&sunhv_reg, 1);
587
588out_free_con_read_page:
589 kfree(con_read_page);
590
591out_free_con_write_page:
592 kfree(con_write_page);
593
594out_free_port:
595 kfree(port);
596 sunhv_port = NULL;
597 return err;
598}
599
600static int hv_remove(struct platform_device *dev)
601{
602 struct uart_port *port = platform_get_drvdata(dev);
603
604 free_irq(port->irq, port);
605
606 uart_remove_one_port(&sunhv_reg, port);
607
608 sunserial_unregister_minors(&sunhv_reg, 1);
609
610 kfree(port);
611 sunhv_port = NULL;
612
613 return 0;
614}
615
616static const struct of_device_id hv_match[] = {
617 {
618 .name = "console",
619 .compatible = "qcn",
620 },
621 {
622 .name = "console",
623 .compatible = "SUNW,sun4v-console",
624 },
625 {},
626};
627MODULE_DEVICE_TABLE(of, hv_match);
628
629static struct platform_driver hv_driver = {
630 .driver = {
631 .name = "hv",
632 .owner = THIS_MODULE,
633 .of_match_table = hv_match,
634 },
635 .probe = hv_probe,
636 .remove = hv_remove,
637};
638
639static int __init sunhv_init(void)
640{
641 if (tlb_type != hypervisor)
642 return -ENODEV;
643
644 return platform_driver_register(&hv_driver);
645}
646
647static void __exit sunhv_exit(void)
648{
649 platform_driver_unregister(&hv_driver);
650}
651
652module_init(sunhv_init);
653module_exit(sunhv_exit);
654
655MODULE_AUTHOR("David S. Miller");
656MODULE_DESCRIPTION("SUN4V Hypervisor console driver");
657MODULE_VERSION("2.0");
658MODULE_LICENSE("GPL");