Loading...
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// 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.h>
21#include <linux/platform_device.h>
22
23#include <asm/hypervisor.h>
24#include <asm/spitfire.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 uart_xmit_advance(port, 1);
51 }
52}
53
54static void transmit_chars_write(struct uart_port *port, struct circ_buf *xmit)
55{
56 while (!uart_circ_empty(xmit)) {
57 unsigned long ra = __pa(xmit->buf + xmit->tail);
58 unsigned long len, status, sent;
59
60 len = CIRC_CNT_TO_END(xmit->head, xmit->tail,
61 UART_XMIT_SIZE);
62 status = sun4v_con_write(ra, len, &sent);
63 if (status != HV_EOK)
64 break;
65 uart_xmit_advance(port, sent);
66 }
67}
68
69static int receive_chars_getchar(struct uart_port *port)
70{
71 int saw_console_brk = 0;
72 int limit = 10000;
73
74 while (limit-- > 0) {
75 long status;
76 long c = sun4v_con_getchar(&status);
77
78 if (status == HV_EWOULDBLOCK)
79 break;
80
81 if (c == CON_BREAK) {
82 if (uart_handle_break(port))
83 continue;
84 saw_console_brk = 1;
85 c = 0;
86 }
87
88 if (c == CON_HUP) {
89 hung_up = 1;
90 uart_handle_dcd_change(port, false);
91 } else if (hung_up) {
92 hung_up = 0;
93 uart_handle_dcd_change(port, true);
94 }
95
96 if (port->state == NULL) {
97 uart_handle_sysrq_char(port, c);
98 continue;
99 }
100
101 port->icount.rx++;
102
103 if (uart_handle_sysrq_char(port, c))
104 continue;
105
106 tty_insert_flip_char(&port->state->port, c, TTY_NORMAL);
107 }
108
109 return saw_console_brk;
110}
111
112static int receive_chars_read(struct uart_port *port)
113{
114 static int saw_console_brk;
115 int limit = 10000;
116
117 while (limit-- > 0) {
118 unsigned long ra = __pa(con_read_page);
119 unsigned long bytes_read, i;
120 long stat = sun4v_con_read(ra, PAGE_SIZE, &bytes_read);
121
122 if (stat != HV_EOK) {
123 bytes_read = 0;
124
125 if (stat == CON_BREAK) {
126 if (saw_console_brk)
127 sun_do_break();
128
129 if (uart_handle_break(port))
130 continue;
131 saw_console_brk = 1;
132 *con_read_page = 0;
133 bytes_read = 1;
134 } else if (stat == CON_HUP) {
135 hung_up = 1;
136 uart_handle_dcd_change(port, false);
137 continue;
138 } else {
139 /* HV_EWOULDBLOCK, etc. */
140 break;
141 }
142 }
143
144 if (hung_up) {
145 hung_up = 0;
146 uart_handle_dcd_change(port, true);
147 }
148
149 if (port->sysrq != 0 && *con_read_page) {
150 for (i = 0; i < bytes_read; i++)
151 uart_handle_sysrq_char(port, con_read_page[i]);
152 saw_console_brk = 0;
153 }
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 const struct sunhv_ops bychar_ops = {
173 .transmit_chars = transmit_chars_putchar,
174 .receive_chars = receive_chars_getchar,
175};
176
177static const struct sunhv_ops bywrite_ops = {
178 .transmit_chars = transmit_chars_write,
179 .receive_chars = receive_chars_read,
180};
181
182static const 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 uart_port_lock_irqsave(port, &flags);
221 tport = receive_chars(port);
222 transmit_chars(port);
223 uart_port_unlock_irqrestore(port, 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 if (ch == __DISABLED_CHAR)
272 return;
273
274 uart_port_lock_irqsave(port, &flags);
275
276 while (limit-- > 0) {
277 long status = sun4v_con_putchar(ch);
278 if (status == HV_EOK)
279 break;
280 udelay(1);
281 }
282
283 uart_port_unlock_irqrestore(port, flags);
284}
285
286/* port->lock held by caller. */
287static void sunhv_stop_rx(struct uart_port *port)
288{
289}
290
291/* port->lock is not held. */
292static void sunhv_break_ctl(struct uart_port *port, int break_state)
293{
294 if (break_state) {
295 unsigned long flags;
296 int limit = 10000;
297
298 uart_port_lock_irqsave(port, &flags);
299
300 while (limit-- > 0) {
301 long status = sun4v_con_putchar(CON_BREAK);
302 if (status == HV_EOK)
303 break;
304 udelay(1);
305 }
306
307 uart_port_unlock_irqrestore(port, flags);
308 }
309}
310
311/* port->lock is not held. */
312static int sunhv_startup(struct uart_port *port)
313{
314 return 0;
315}
316
317/* port->lock is not held. */
318static void sunhv_shutdown(struct uart_port *port)
319{
320}
321
322/* port->lock is not held. */
323static void sunhv_set_termios(struct uart_port *port, struct ktermios *termios,
324 const struct ktermios *old)
325{
326 unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
327 unsigned int quot = uart_get_divisor(port, baud);
328 unsigned int iflag, cflag;
329 unsigned long flags;
330
331 uart_port_lock_irqsave(port, &flags);
332
333 iflag = termios->c_iflag;
334 cflag = termios->c_cflag;
335
336 port->ignore_status_mask = 0;
337 if (iflag & IGNBRK)
338 port->ignore_status_mask |= IGNORE_BREAK;
339 if ((cflag & CREAD) == 0)
340 port->ignore_status_mask |= IGNORE_ALL;
341
342 /* XXX */
343 uart_update_timeout(port, cflag,
344 (port->uartclk / (16 * quot)));
345
346 uart_port_unlock_irqrestore(port, flags);
347}
348
349static const char *sunhv_type(struct uart_port *port)
350{
351 return "SUN4V HCONS";
352}
353
354static void sunhv_release_port(struct uart_port *port)
355{
356}
357
358static int sunhv_request_port(struct uart_port *port)
359{
360 return 0;
361}
362
363static void sunhv_config_port(struct uart_port *port, int flags)
364{
365}
366
367static int sunhv_verify_port(struct uart_port *port, struct serial_struct *ser)
368{
369 return -EINVAL;
370}
371
372static const struct uart_ops sunhv_pops = {
373 .tx_empty = sunhv_tx_empty,
374 .set_mctrl = sunhv_set_mctrl,
375 .get_mctrl = sunhv_get_mctrl,
376 .stop_tx = sunhv_stop_tx,
377 .start_tx = sunhv_start_tx,
378 .send_xchar = sunhv_send_xchar,
379 .stop_rx = sunhv_stop_rx,
380 .break_ctl = sunhv_break_ctl,
381 .startup = sunhv_startup,
382 .shutdown = sunhv_shutdown,
383 .set_termios = sunhv_set_termios,
384 .type = sunhv_type,
385 .release_port = sunhv_release_port,
386 .request_port = sunhv_request_port,
387 .config_port = sunhv_config_port,
388 .verify_port = sunhv_verify_port,
389};
390
391static struct uart_driver sunhv_reg = {
392 .owner = THIS_MODULE,
393 .driver_name = "sunhv",
394 .dev_name = "ttyHV",
395 .major = TTY_MAJOR,
396};
397
398static struct uart_port *sunhv_port;
399
400void sunhv_migrate_hvcons_irq(int cpu)
401{
402 /* Migrate hvcons irq to param cpu */
403 irq_force_affinity(sunhv_port->irq, cpumask_of(cpu));
404}
405
406/* Copy 's' into the con_write_page, decoding "\n" into
407 * "\r\n" along the way. We have to return two lengths
408 * because the caller needs to know how much to advance
409 * 's' and also how many bytes to output via con_write_page.
410 */
411static int fill_con_write_page(const char *s, unsigned int n,
412 unsigned long *page_bytes)
413{
414 const char *orig_s = s;
415 char *p = con_write_page;
416 int left = PAGE_SIZE;
417
418 while (n--) {
419 if (*s == '\n') {
420 if (left < 2)
421 break;
422 *p++ = '\r';
423 left--;
424 } else if (left < 1)
425 break;
426 *p++ = *s++;
427 left--;
428 }
429 *page_bytes = p - con_write_page;
430 return s - orig_s;
431}
432
433static void sunhv_console_write_paged(struct console *con, const char *s, unsigned n)
434{
435 struct uart_port *port = sunhv_port;
436 unsigned long flags;
437 int locked = 1;
438
439 if (port->sysrq || oops_in_progress)
440 locked = uart_port_trylock_irqsave(port, &flags);
441 else
442 uart_port_lock_irqsave(port, &flags);
443
444 while (n > 0) {
445 unsigned long ra = __pa(con_write_page);
446 unsigned long page_bytes;
447 unsigned int cpy = fill_con_write_page(s, n,
448 &page_bytes);
449
450 n -= cpy;
451 s += cpy;
452 while (page_bytes > 0) {
453 unsigned long written;
454 int limit = 1000000;
455
456 while (limit--) {
457 unsigned long stat;
458
459 stat = sun4v_con_write(ra, page_bytes,
460 &written);
461 if (stat == HV_EOK)
462 break;
463 udelay(1);
464 }
465 if (limit < 0)
466 break;
467 page_bytes -= written;
468 ra += written;
469 }
470 }
471
472 if (locked)
473 uart_port_unlock_irqrestore(port, 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 if (port->sysrq || oops_in_progress)
495 locked = uart_port_trylock_irqsave(port, &flags);
496 else
497 uart_port_lock_irqsave(port, &flags);
498
499 for (i = 0; i < n; i++) {
500 if (*s == '\n')
501 sunhv_console_putchar(port, '\r');
502 sunhv_console_putchar(port, *s++);
503 }
504
505 if (locked)
506 uart_port_unlock_irqrestore(port, flags);
507}
508
509static struct console sunhv_console = {
510 .name = "ttyHV",
511 .write = sunhv_console_write_bychar,
512 .device = uart_console_device,
513 .flags = CON_PRINTBUFFER,
514 .index = -1,
515 .data = &sunhv_reg,
516};
517
518static int hv_probe(struct platform_device *op)
519{
520 struct uart_port *port;
521 unsigned long minor;
522 int err;
523
524 if (op->archdata.irqs[0] == 0xffffffff)
525 return -ENODEV;
526
527 port = kzalloc(sizeof(struct uart_port), GFP_KERNEL);
528 if (unlikely(!port))
529 return -ENOMEM;
530
531 minor = 1;
532 if (sun4v_hvapi_register(HV_GRP_CORE, 1, &minor) == 0 &&
533 minor >= 1) {
534 err = -ENOMEM;
535 con_write_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
536 if (!con_write_page)
537 goto out_free_port;
538
539 con_read_page = kzalloc(PAGE_SIZE, GFP_KERNEL);
540 if (!con_read_page)
541 goto out_free_con_write_page;
542
543 sunhv_console.write = sunhv_console_write_paged;
544 sunhv_ops = &bywrite_ops;
545 }
546
547 sunhv_port = port;
548
549 port->has_sysrq = 1;
550 port->line = 0;
551 port->ops = &sunhv_pops;
552 port->type = PORT_SUNHV;
553 port->uartclk = ( 29491200 / 16 ); /* arbitrary */
554
555 port->membase = (unsigned char __iomem *) __pa(port);
556
557 port->irq = op->archdata.irqs[0];
558
559 port->dev = &op->dev;
560
561 err = sunserial_register_minors(&sunhv_reg, 1);
562 if (err)
563 goto out_free_con_read_page;
564
565 sunserial_console_match(&sunhv_console, op->dev.of_node,
566 &sunhv_reg, port->line, false);
567
568 err = uart_add_one_port(&sunhv_reg, port);
569 if (err)
570 goto out_unregister_driver;
571
572 err = request_irq(port->irq, sunhv_interrupt, 0, "hvcons", port);
573 if (err)
574 goto out_remove_port;
575
576 platform_set_drvdata(op, port);
577
578 return 0;
579
580out_remove_port:
581 uart_remove_one_port(&sunhv_reg, port);
582
583out_unregister_driver:
584 sunserial_unregister_minors(&sunhv_reg, 1);
585
586out_free_con_read_page:
587 kfree(con_read_page);
588
589out_free_con_write_page:
590 kfree(con_write_page);
591
592out_free_port:
593 kfree(port);
594 sunhv_port = NULL;
595 return err;
596}
597
598static void hv_remove(struct platform_device *dev)
599{
600 struct uart_port *port = platform_get_drvdata(dev);
601
602 free_irq(port->irq, port);
603
604 uart_remove_one_port(&sunhv_reg, port);
605
606 sunserial_unregister_minors(&sunhv_reg, 1);
607 kfree(con_read_page);
608 kfree(con_write_page);
609 kfree(port);
610 sunhv_port = NULL;
611}
612
613static const struct of_device_id hv_match[] = {
614 {
615 .name = "console",
616 .compatible = "qcn",
617 },
618 {
619 .name = "console",
620 .compatible = "SUNW,sun4v-console",
621 },
622 {},
623};
624
625static struct platform_driver hv_driver = {
626 .driver = {
627 .name = "hv",
628 .of_match_table = hv_match,
629 },
630 .probe = hv_probe,
631 .remove_new = hv_remove,
632};
633
634static int __init sunhv_init(void)
635{
636 if (tlb_type != hypervisor)
637 return -ENODEV;
638
639 return platform_driver_register(&hv_driver);
640}
641device_initcall(sunhv_init);
642
643#if 0 /* ...def MODULE ; never supported as such */
644MODULE_AUTHOR("David S. Miller");
645MODULE_DESCRIPTION("SUN4V Hypervisor console driver");
646MODULE_VERSION("2.0");
647MODULE_LICENSE("GPL");
648#endif