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