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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// SPDX-License-Identifier: GPL-2.0
2/* sunhv.c: Serial driver for SUN4V hypervisor console.
3 *
4 * Copyright (C) 2006, 2007 David S. Miller (davem@davemloft.net)
5 */
6
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#include <linux/serial_core.h>
29#include <linux/sunserialcore.h>
30
31#define CON_BREAK ((long)-1)
32#define CON_HUP ((long)-2)
33
34#define IGNORE_BREAK 0x1
35#define IGNORE_ALL 0x2
36
37static char *con_write_page;
38static char *con_read_page;
39
40static int hung_up = 0;
41
42static void transmit_chars_putchar(struct uart_port *port, struct circ_buf *xmit)
43{
44 while (!uart_circ_empty(xmit)) {
45 long status = sun4v_con_putchar(xmit->buf[xmit->tail]);
46
47 if (status != HV_EOK)
48 break;
49
50 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
51 port->icount.tx++;
52 }
53}
54
55static void transmit_chars_write(struct uart_port *port, struct circ_buf *xmit)
56{
57 while (!uart_circ_empty(xmit)) {
58 unsigned long ra = __pa(xmit->buf + xmit->tail);
59 unsigned long len, status, sent;
60
61 len = CIRC_CNT_TO_END(xmit->head, xmit->tail,
62 UART_XMIT_SIZE);
63 status = sun4v_con_write(ra, len, &sent);
64 if (status != HV_EOK)
65 break;
66 xmit->tail = (xmit->tail + sent) & (UART_XMIT_SIZE - 1);
67 port->icount.tx += sent;
68 }
69}
70
71static int receive_chars_getchar(struct uart_port *port)
72{
73 int saw_console_brk = 0;
74 int limit = 10000;
75
76 while (limit-- > 0) {
77 long status;
78 long c = sun4v_con_getchar(&status);
79
80 if (status == HV_EWOULDBLOCK)
81 break;
82
83 if (c == CON_BREAK) {
84 if (uart_handle_break(port))
85 continue;
86 saw_console_brk = 1;
87 c = 0;
88 }
89
90 if (c == CON_HUP) {
91 hung_up = 1;
92 uart_handle_dcd_change(port, 0);
93 } else if (hung_up) {
94 hung_up = 0;
95 uart_handle_dcd_change(port, 1);
96 }
97
98 if (port->state == NULL) {
99 uart_handle_sysrq_char(port, c);
100 continue;
101 }
102
103 port->icount.rx++;
104
105 if (uart_handle_sysrq_char(port, c))
106 continue;
107
108 tty_insert_flip_char(&port->state->port, c, TTY_NORMAL);
109 }
110
111 return saw_console_brk;
112}
113
114static int receive_chars_read(struct uart_port *port)
115{
116 static int saw_console_brk;
117 int limit = 10000;
118
119 while (limit-- > 0) {
120 unsigned long ra = __pa(con_read_page);
121 unsigned long bytes_read, i;
122 long stat = sun4v_con_read(ra, PAGE_SIZE, &bytes_read);
123
124 if (stat != HV_EOK) {
125 bytes_read = 0;
126
127 if (stat == CON_BREAK) {
128 if (saw_console_brk)
129 sun_do_break();
130
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 saw_console_brk = 0;
155 }
156
157 if (port->state == NULL)
158 continue;
159
160 port->icount.rx += bytes_read;
161
162 tty_insert_flip_string(&port->state->port, con_read_page,
163 bytes_read);
164 }
165
166 return saw_console_brk;
167}
168
169struct sunhv_ops {
170 void (*transmit_chars)(struct uart_port *port, struct circ_buf *xmit);
171 int (*receive_chars)(struct uart_port *port);
172};
173
174static const struct sunhv_ops bychar_ops = {
175 .transmit_chars = transmit_chars_putchar,
176 .receive_chars = receive_chars_getchar,
177};
178
179static const struct sunhv_ops bywrite_ops = {
180 .transmit_chars = transmit_chars_write,
181 .receive_chars = receive_chars_read,
182};
183
184static const struct sunhv_ops *sunhv_ops = &bychar_ops;
185
186static struct tty_port *receive_chars(struct uart_port *port)
187{
188 struct tty_port *tport = NULL;
189
190 if (port->state != NULL) /* Unopened serial console */
191 tport = &port->state->port;
192
193 if (sunhv_ops->receive_chars(port))
194 sun_do_break();
195
196 return tport;
197}
198
199static void transmit_chars(struct uart_port *port)
200{
201 struct circ_buf *xmit;
202
203 if (!port->state)
204 return;
205
206 xmit = &port->state->xmit;
207 if (uart_circ_empty(xmit) || uart_tx_stopped(port))
208 return;
209
210 sunhv_ops->transmit_chars(port, xmit);
211
212 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
213 uart_write_wakeup(port);
214}
215
216static irqreturn_t sunhv_interrupt(int irq, void *dev_id)
217{
218 struct uart_port *port = dev_id;
219 struct tty_port *tport;
220 unsigned long flags;
221
222 spin_lock_irqsave(&port->lock, flags);
223 tport = receive_chars(port);
224 transmit_chars(port);
225 spin_unlock_irqrestore(&port->lock, flags);
226
227 if (tport)
228 tty_flip_buffer_push(tport);
229
230 return IRQ_HANDLED;
231}
232
233/* port->lock is not held. */
234static unsigned int sunhv_tx_empty(struct uart_port *port)
235{
236 /* Transmitter is always empty for us. If the circ buffer
237 * is non-empty or there is an x_char pending, our caller
238 * will do the right thing and ignore what we return here.
239 */
240 return TIOCSER_TEMT;
241}
242
243/* port->lock held by caller. */
244static void sunhv_set_mctrl(struct uart_port *port, unsigned int mctrl)
245{
246 return;
247}
248
249/* port->lock is held by caller and interrupts are disabled. */
250static unsigned int sunhv_get_mctrl(struct uart_port *port)
251{
252 return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
253}
254
255/* port->lock held by caller. */
256static void sunhv_stop_tx(struct uart_port *port)
257{
258 return;
259}
260
261/* port->lock held by caller. */
262static void sunhv_start_tx(struct uart_port *port)
263{
264 transmit_chars(port);
265}
266
267/* port->lock is not held. */
268static void sunhv_send_xchar(struct uart_port *port, char ch)
269{
270 unsigned long flags;
271 int limit = 10000;
272
273 if (ch == __DISABLED_CHAR)
274 return;
275
276 spin_lock_irqsave(&port->lock, flags);
277
278 while (limit-- > 0) {
279 long status = sun4v_con_putchar(ch);
280 if (status == HV_EOK)
281 break;
282 udelay(1);
283 }
284
285 spin_unlock_irqrestore(&port->lock, flags);
286}
287
288/* port->lock held by caller. */
289static void sunhv_stop_rx(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 const 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 .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 = "ttyHV",
397 .major = TTY_MAJOR,
398};
399
400static struct uart_port *sunhv_port;
401
402void sunhv_migrate_hvcons_irq(int cpu)
403{
404 /* Migrate hvcons irq to param cpu */
405 irq_force_affinity(sunhv_port->irq, cpumask_of(cpu));
406}
407
408/* Copy 's' into the con_write_page, decoding "\n" into
409 * "\r\n" along the way. We have to return two lengths
410 * because the caller needs to know how much to advance
411 * 's' and also how many bytes to output via con_write_page.
412 */
413static int fill_con_write_page(const char *s, unsigned int n,
414 unsigned long *page_bytes)
415{
416 const char *orig_s = s;
417 char *p = con_write_page;
418 int left = PAGE_SIZE;
419
420 while (n--) {
421 if (*s == '\n') {
422 if (left < 2)
423 break;
424 *p++ = '\r';
425 left--;
426 } else if (left < 1)
427 break;
428 *p++ = *s++;
429 left--;
430 }
431 *page_bytes = p - con_write_page;
432 return s - orig_s;
433}
434
435static void sunhv_console_write_paged(struct console *con, const char *s, unsigned n)
436{
437 struct uart_port *port = sunhv_port;
438 unsigned long flags;
439 int locked = 1;
440
441 if (port->sysrq || oops_in_progress)
442 locked = spin_trylock_irqsave(&port->lock, flags);
443 else
444 spin_lock_irqsave(&port->lock, flags);
445
446 while (n > 0) {
447 unsigned long ra = __pa(con_write_page);
448 unsigned long page_bytes;
449 unsigned int cpy = fill_con_write_page(s, n,
450 &page_bytes);
451
452 n -= cpy;
453 s += cpy;
454 while (page_bytes > 0) {
455 unsigned long written;
456 int limit = 1000000;
457
458 while (limit--) {
459 unsigned long stat;
460
461 stat = sun4v_con_write(ra, page_bytes,
462 &written);
463 if (stat == HV_EOK)
464 break;
465 udelay(1);
466 }
467 if (limit < 0)
468 break;
469 page_bytes -= written;
470 ra += written;
471 }
472 }
473
474 if (locked)
475 spin_unlock_irqrestore(&port->lock, flags);
476}
477
478static inline void sunhv_console_putchar(struct uart_port *port, char c)
479{
480 int limit = 1000000;
481
482 while (limit-- > 0) {
483 long status = sun4v_con_putchar(c);
484 if (status == HV_EOK)
485 break;
486 udelay(1);
487 }
488}
489
490static void sunhv_console_write_bychar(struct console *con, const char *s, unsigned n)
491{
492 struct uart_port *port = sunhv_port;
493 unsigned long flags;
494 int i, locked = 1;
495
496 if (port->sysrq || oops_in_progress)
497 locked = spin_trylock_irqsave(&port->lock, flags);
498 else
499 spin_lock_irqsave(&port->lock, flags);
500
501 for (i = 0; i < n; i++) {
502 if (*s == '\n')
503 sunhv_console_putchar(port, '\r');
504 sunhv_console_putchar(port, *s++);
505 }
506
507 if (locked)
508 spin_unlock_irqrestore(&port->lock, flags);
509}
510
511static struct console sunhv_console = {
512 .name = "ttyHV",
513 .write = sunhv_console_write_bychar,
514 .device = uart_console_device,
515 .flags = CON_PRINTBUFFER,
516 .index = -1,
517 .data = &sunhv_reg,
518};
519
520static int hv_probe(struct platform_device *op)
521{
522 struct uart_port *port;
523 unsigned long minor;
524 int err;
525
526 if (op->archdata.irqs[0] == 0xffffffff)
527 return -ENODEV;
528
529 port = kzalloc(sizeof(struct uart_port), GFP_KERNEL);
530 if (unlikely(!port))
531 return -ENOMEM;
532
533 minor = 1;
534 if (sun4v_hvapi_register(HV_GRP_CORE, 1, &minor) == 0 &&
535 minor >= 1) {
536 err = -ENOMEM;
537 con_write_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
538 if (!con_write_page)
539 goto out_free_port;
540
541 con_read_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
542 if (!con_read_page)
543 goto out_free_con_write_page;
544
545 sunhv_console.write = sunhv_console_write_paged;
546 sunhv_ops = &bywrite_ops;
547 }
548
549 sunhv_port = port;
550
551 port->has_sysrq = 1;
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 kfree(con_read_page);
610 kfree(con_write_page);
611 kfree(port);
612 sunhv_port = NULL;
613
614 return 0;
615}
616
617static const struct of_device_id hv_match[] = {
618 {
619 .name = "console",
620 .compatible = "qcn",
621 },
622 {
623 .name = "console",
624 .compatible = "SUNW,sun4v-console",
625 },
626 {},
627};
628
629static struct platform_driver hv_driver = {
630 .driver = {
631 .name = "hv",
632 .of_match_table = hv_match,
633 },
634 .probe = hv_probe,
635 .remove = hv_remove,
636};
637
638static int __init sunhv_init(void)
639{
640 if (tlb_type != hypervisor)
641 return -ENODEV;
642
643 return platform_driver_register(&hv_driver);
644}
645device_initcall(sunhv_init);
646
647#if 0 /* ...def MODULE ; never supported as such */
648MODULE_AUTHOR("David S. Miller");
649MODULE_DESCRIPTION("SUN4V Hypervisor console driver");
650MODULE_VERSION("2.0");
651MODULE_LICENSE("GPL");
652#endif