xref: /openbmc/linux/drivers/s390/char/con3270.c (revision b34e08d5)
1 /*
2  * IBM/3270 Driver - console view.
3  *
4  * Author(s):
5  *   Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
6  *   Rewritten for 2.5 by Martin Schwidefsky <schwidefsky@de.ibm.com>
7  *     Copyright IBM Corp. 2003, 2009
8  */
9 
10 #include <linux/module.h>
11 #include <linux/console.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/list.h>
15 #include <linux/types.h>
16 #include <linux/slab.h>
17 #include <linux/err.h>
18 #include <linux/reboot.h>
19 
20 #include <asm/ccwdev.h>
21 #include <asm/cio.h>
22 #include <asm/cpcmd.h>
23 #include <asm/ebcdic.h>
24 
25 #include "raw3270.h"
26 #include "tty3270.h"
27 #include "ctrlchar.h"
28 
29 #define CON3270_OUTPUT_BUFFER_SIZE 1024
30 #define CON3270_STRING_PAGES 4
31 
32 static struct raw3270_fn con3270_fn;
33 
34 static bool auto_update = 1;
35 module_param(auto_update, bool, 0);
36 
37 /*
38  * Main 3270 console view data structure.
39  */
40 struct con3270 {
41 	struct raw3270_view view;
42 	struct list_head freemem;	/* list of free memory for strings. */
43 
44 	/* Output stuff. */
45 	struct list_head lines;		/* list of lines. */
46 	struct list_head update;	/* list of lines to update. */
47 	int line_nr;			/* line number for next update. */
48 	int nr_lines;			/* # lines in list. */
49 	int nr_up;			/* # lines up in history. */
50 	unsigned long update_flags;	/* Update indication bits. */
51 	struct string *cline;		/* current output line. */
52 	struct string *status;		/* last line of display. */
53 	struct raw3270_request *write;	/* single write request. */
54 	struct timer_list timer;
55 
56 	/* Input stuff. */
57 	struct string *input;		/* input string for read request. */
58 	struct raw3270_request *read;	/* single read request. */
59 	struct raw3270_request *kreset;	/* single keyboard reset request. */
60 	struct tasklet_struct readlet;	/* tasklet to issue read request. */
61 };
62 
63 static struct con3270 *condev;
64 
65 /* con3270->update_flags. See con3270_update for details. */
66 #define CON_UPDATE_ERASE	1	/* Use EWRITEA instead of WRITE. */
67 #define CON_UPDATE_LIST		2	/* Update lines in tty3270->update. */
68 #define CON_UPDATE_STATUS	4	/* Update status line. */
69 #define CON_UPDATE_ALL		8	/* Recreate screen. */
70 
71 static void con3270_update(struct con3270 *);
72 
73 /*
74  * Setup timeout for a device. On timeout trigger an update.
75  */
76 static void con3270_set_timer(struct con3270 *cp, int expires)
77 {
78 	if (expires == 0)
79 		del_timer(&cp->timer);
80 	else
81 		mod_timer(&cp->timer, jiffies + expires);
82 }
83 
84 /*
85  * The status line is the last line of the screen. It shows the string
86  * "console view" in the lower left corner and "Running"/"More..."/"Holding"
87  * in the lower right corner of the screen.
88  */
89 static void
90 con3270_update_status(struct con3270 *cp)
91 {
92 	char *str;
93 
94 	str = (cp->nr_up != 0) ? "History" : "Running";
95 	memcpy(cp->status->string + 24, str, 7);
96 	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
97 	cp->update_flags |= CON_UPDATE_STATUS;
98 }
99 
100 static void
101 con3270_create_status(struct con3270 *cp)
102 {
103 	static const unsigned char blueprint[] =
104 		{ TO_SBA, 0, 0, TO_SF,TF_LOG,TO_SA,TAT_COLOR, TAC_GREEN,
105 		  'c','o','n','s','o','l','e',' ','v','i','e','w',
106 		  TO_RA,0,0,0,'R','u','n','n','i','n','g',TO_SF,TF_LOG };
107 
108 	cp->status = alloc_string(&cp->freemem, sizeof(blueprint));
109 	/* Copy blueprint to status line */
110 	memcpy(cp->status->string, blueprint, sizeof(blueprint));
111 	/* Set TO_RA addresses. */
112 	raw3270_buffer_address(cp->view.dev, cp->status->string + 1,
113 			       cp->view.cols * (cp->view.rows - 1));
114 	raw3270_buffer_address(cp->view.dev, cp->status->string + 21,
115 			       cp->view.cols * cp->view.rows - 8);
116 	/* Convert strings to ebcdic. */
117 	codepage_convert(cp->view.ascebc, cp->status->string + 8, 12);
118 	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
119 }
120 
121 /*
122  * Set output offsets to 3270 datastream fragment of a console string.
123  */
124 static void
125 con3270_update_string(struct con3270 *cp, struct string *s, int nr)
126 {
127 	if (s->len >= cp->view.cols - 5)
128 		return;
129 	raw3270_buffer_address(cp->view.dev, s->string + s->len - 3,
130 			       cp->view.cols * (nr + 1));
131 }
132 
133 /*
134  * Rebuild update list to print all lines.
135  */
136 static void
137 con3270_rebuild_update(struct con3270 *cp)
138 {
139 	struct string *s, *n;
140 	int nr;
141 
142 	/*
143 	 * Throw away update list and create a new one,
144 	 * containing all lines that will fit on the screen.
145 	 */
146 	list_for_each_entry_safe(s, n, &cp->update, update)
147 		list_del_init(&s->update);
148 	nr = cp->view.rows - 2 + cp->nr_up;
149 	list_for_each_entry_reverse(s, &cp->lines, list) {
150 		if (nr < cp->view.rows - 1)
151 			list_add(&s->update, &cp->update);
152 		if (--nr < 0)
153 			break;
154 	}
155 	cp->line_nr = 0;
156 	cp->update_flags |= CON_UPDATE_LIST;
157 }
158 
159 /*
160  * Alloc string for size bytes. Free strings from history if necessary.
161  */
162 static struct string *
163 con3270_alloc_string(struct con3270 *cp, size_t size)
164 {
165 	struct string *s, *n;
166 
167 	s = alloc_string(&cp->freemem, size);
168 	if (s)
169 		return s;
170 	list_for_each_entry_safe(s, n, &cp->lines, list) {
171 		list_del(&s->list);
172 		if (!list_empty(&s->update))
173 			list_del(&s->update);
174 		cp->nr_lines--;
175 		if (free_string(&cp->freemem, s) >= size)
176 			break;
177 	}
178 	s = alloc_string(&cp->freemem, size);
179 	BUG_ON(!s);
180 	if (cp->nr_up != 0 && cp->nr_up + cp->view.rows > cp->nr_lines) {
181 		cp->nr_up = cp->nr_lines - cp->view.rows + 1;
182 		con3270_rebuild_update(cp);
183 		con3270_update_status(cp);
184 	}
185 	return s;
186 }
187 
188 /*
189  * Write completion callback.
190  */
191 static void
192 con3270_write_callback(struct raw3270_request *rq, void *data)
193 {
194 	raw3270_request_reset(rq);
195 	xchg(&((struct con3270 *) rq->view)->write, rq);
196 }
197 
198 /*
199  * Update console display.
200  */
201 static void
202 con3270_update(struct con3270 *cp)
203 {
204 	struct raw3270_request *wrq;
205 	char wcc, prolog[6];
206 	unsigned long flags;
207 	unsigned long updated;
208 	struct string *s, *n;
209 	int rc;
210 
211 	if (!auto_update && !raw3270_view_active(&cp->view))
212 		return;
213 	if (cp->view.dev)
214 		raw3270_activate_view(&cp->view);
215 
216 	wrq = xchg(&cp->write, 0);
217 	if (!wrq) {
218 		con3270_set_timer(cp, 1);
219 		return;
220 	}
221 
222 	spin_lock_irqsave(&cp->view.lock, flags);
223 	updated = 0;
224 	if (cp->update_flags & CON_UPDATE_ALL) {
225 		con3270_rebuild_update(cp);
226 		con3270_update_status(cp);
227 		cp->update_flags = CON_UPDATE_ERASE | CON_UPDATE_LIST |
228 			CON_UPDATE_STATUS;
229 	}
230 	if (cp->update_flags & CON_UPDATE_ERASE) {
231 		/* Use erase write alternate to initialize display. */
232 		raw3270_request_set_cmd(wrq, TC_EWRITEA);
233 		updated |= CON_UPDATE_ERASE;
234 	} else
235 		raw3270_request_set_cmd(wrq, TC_WRITE);
236 
237 	wcc = TW_NONE;
238 	raw3270_request_add_data(wrq, &wcc, 1);
239 
240 	/*
241 	 * Update status line.
242 	 */
243 	if (cp->update_flags & CON_UPDATE_STATUS)
244 		if (raw3270_request_add_data(wrq, cp->status->string,
245 					     cp->status->len) == 0)
246 			updated |= CON_UPDATE_STATUS;
247 
248 	if (cp->update_flags & CON_UPDATE_LIST) {
249 		prolog[0] = TO_SBA;
250 		prolog[3] = TO_SA;
251 		prolog[4] = TAT_COLOR;
252 		prolog[5] = TAC_TURQ;
253 		raw3270_buffer_address(cp->view.dev, prolog + 1,
254 				       cp->view.cols * cp->line_nr);
255 		raw3270_request_add_data(wrq, prolog, 6);
256 		/* Write strings in the update list to the screen. */
257 		list_for_each_entry_safe(s, n, &cp->update, update) {
258 			if (s != cp->cline)
259 				con3270_update_string(cp, s, cp->line_nr);
260 			if (raw3270_request_add_data(wrq, s->string,
261 						     s->len) != 0)
262 				break;
263 			list_del_init(&s->update);
264 			if (s != cp->cline)
265 				cp->line_nr++;
266 		}
267 		if (list_empty(&cp->update))
268 			updated |= CON_UPDATE_LIST;
269 	}
270 	wrq->callback = con3270_write_callback;
271 	rc = raw3270_start(&cp->view, wrq);
272 	if (rc == 0) {
273 		cp->update_flags &= ~updated;
274 		if (cp->update_flags)
275 			con3270_set_timer(cp, 1);
276 	} else {
277 		raw3270_request_reset(wrq);
278 		xchg(&cp->write, wrq);
279 	}
280 	spin_unlock_irqrestore(&cp->view.lock, flags);
281 }
282 
283 /*
284  * Read tasklet.
285  */
286 static void
287 con3270_read_tasklet(struct raw3270_request *rrq)
288 {
289 	static char kreset_data = TW_KR;
290 	struct con3270 *cp;
291 	unsigned long flags;
292 	int nr_up, deactivate;
293 
294 	cp = (struct con3270 *) rrq->view;
295 	spin_lock_irqsave(&cp->view.lock, flags);
296 	nr_up = cp->nr_up;
297 	deactivate = 0;
298 	/* Check aid byte. */
299 	switch (cp->input->string[0]) {
300 	case 0x7d:	/* enter: jump to bottom. */
301 		nr_up = 0;
302 		break;
303 	case 0xf3:	/* PF3: deactivate the console view. */
304 		deactivate = 1;
305 		break;
306 	case 0x6d:	/* clear: start from scratch. */
307 		cp->update_flags = CON_UPDATE_ALL;
308 		con3270_set_timer(cp, 1);
309 		break;
310 	case 0xf7:	/* PF7: do a page up in the console log. */
311 		nr_up += cp->view.rows - 2;
312 		if (nr_up + cp->view.rows - 1 > cp->nr_lines) {
313 			nr_up = cp->nr_lines - cp->view.rows + 1;
314 			if (nr_up < 0)
315 				nr_up = 0;
316 		}
317 		break;
318 	case 0xf8:	/* PF8: do a page down in the console log. */
319 		nr_up -= cp->view.rows - 2;
320 		if (nr_up < 0)
321 			nr_up = 0;
322 		break;
323 	}
324 	if (nr_up != cp->nr_up) {
325 		cp->nr_up = nr_up;
326 		con3270_rebuild_update(cp);
327 		con3270_update_status(cp);
328 		con3270_set_timer(cp, 1);
329 	}
330 	spin_unlock_irqrestore(&cp->view.lock, flags);
331 
332 	/* Start keyboard reset command. */
333 	raw3270_request_reset(cp->kreset);
334 	raw3270_request_set_cmd(cp->kreset, TC_WRITE);
335 	raw3270_request_add_data(cp->kreset, &kreset_data, 1);
336 	raw3270_start(&cp->view, cp->kreset);
337 
338 	if (deactivate)
339 		raw3270_deactivate_view(&cp->view);
340 
341 	raw3270_request_reset(rrq);
342 	xchg(&cp->read, rrq);
343 	raw3270_put_view(&cp->view);
344 }
345 
346 /*
347  * Read request completion callback.
348  */
349 static void
350 con3270_read_callback(struct raw3270_request *rq, void *data)
351 {
352 	raw3270_get_view(rq->view);
353 	/* Schedule tasklet to pass input to tty. */
354 	tasklet_schedule(&((struct con3270 *) rq->view)->readlet);
355 }
356 
357 /*
358  * Issue a read request. Called only from interrupt function.
359  */
360 static void
361 con3270_issue_read(struct con3270 *cp)
362 {
363 	struct raw3270_request *rrq;
364 	int rc;
365 
366 	rrq = xchg(&cp->read, 0);
367 	if (!rrq)
368 		/* Read already scheduled. */
369 		return;
370 	rrq->callback = con3270_read_callback;
371 	rrq->callback_data = cp;
372 	raw3270_request_set_cmd(rrq, TC_READMOD);
373 	raw3270_request_set_data(rrq, cp->input->string, cp->input->len);
374 	/* Issue the read modified request. */
375 	rc = raw3270_start_irq(&cp->view, rrq);
376 	if (rc)
377 		raw3270_request_reset(rrq);
378 }
379 
380 /*
381  * Switch to the console view.
382  */
383 static int
384 con3270_activate(struct raw3270_view *view)
385 {
386 	struct con3270 *cp;
387 
388 	cp = (struct con3270 *) view;
389 	cp->update_flags = CON_UPDATE_ALL;
390 	con3270_set_timer(cp, 1);
391 	return 0;
392 }
393 
394 static void
395 con3270_deactivate(struct raw3270_view *view)
396 {
397 	struct con3270 *cp;
398 
399 	cp = (struct con3270 *) view;
400 	del_timer(&cp->timer);
401 }
402 
403 static int
404 con3270_irq(struct con3270 *cp, struct raw3270_request *rq, struct irb *irb)
405 {
406 	/* Handle ATTN. Schedule tasklet to read aid. */
407 	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
408 		con3270_issue_read(cp);
409 
410 	if (rq) {
411 		if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
412 			rq->rc = -EIO;
413 		else
414 			/* Normal end. Copy residual count. */
415 			rq->rescnt = irb->scsw.cmd.count;
416 	}
417 	return RAW3270_IO_DONE;
418 }
419 
420 /* Console view to a 3270 device. */
421 static struct raw3270_fn con3270_fn = {
422 	.activate = con3270_activate,
423 	.deactivate = con3270_deactivate,
424 	.intv = (void *) con3270_irq
425 };
426 
427 static inline void
428 con3270_cline_add(struct con3270 *cp)
429 {
430 	if (!list_empty(&cp->cline->list))
431 		/* Already added. */
432 		return;
433 	list_add_tail(&cp->cline->list, &cp->lines);
434 	cp->nr_lines++;
435 	con3270_rebuild_update(cp);
436 }
437 
438 static inline void
439 con3270_cline_insert(struct con3270 *cp, unsigned char c)
440 {
441 	cp->cline->string[cp->cline->len++] =
442 		cp->view.ascebc[(c < ' ') ? ' ' : c];
443 	if (list_empty(&cp->cline->update)) {
444 		list_add_tail(&cp->cline->update, &cp->update);
445 		cp->update_flags |= CON_UPDATE_LIST;
446 	}
447 }
448 
449 static inline void
450 con3270_cline_end(struct con3270 *cp)
451 {
452 	struct string *s;
453 	unsigned int size;
454 
455 	/* Copy cline. */
456 	size = (cp->cline->len < cp->view.cols - 5) ?
457 		cp->cline->len + 4 : cp->view.cols;
458 	s = con3270_alloc_string(cp, size);
459 	memcpy(s->string, cp->cline->string, cp->cline->len);
460 	if (s->len < cp->view.cols - 5) {
461 		s->string[s->len - 4] = TO_RA;
462 		s->string[s->len - 1] = 0;
463 	} else {
464 		while (--size > cp->cline->len)
465 			s->string[size] = cp->view.ascebc[' '];
466 	}
467 	/* Replace cline with allocated line s and reset cline. */
468 	list_add(&s->list, &cp->cline->list);
469 	list_del_init(&cp->cline->list);
470 	if (!list_empty(&cp->cline->update)) {
471 		list_add(&s->update, &cp->cline->update);
472 		list_del_init(&cp->cline->update);
473 	}
474 	cp->cline->len = 0;
475 }
476 
477 /*
478  * Write a string to the 3270 console
479  */
480 static void
481 con3270_write(struct console *co, const char *str, unsigned int count)
482 {
483 	struct con3270 *cp;
484 	unsigned long flags;
485 	unsigned char c;
486 
487 	cp = condev;
488 	spin_lock_irqsave(&cp->view.lock, flags);
489 	while (count-- > 0) {
490 		c = *str++;
491 		if (cp->cline->len == 0)
492 			con3270_cline_add(cp);
493 		if (c != '\n')
494 			con3270_cline_insert(cp, c);
495 		if (c == '\n' || cp->cline->len >= cp->view.cols)
496 			con3270_cline_end(cp);
497 	}
498 	/* Setup timer to output current console buffer after 1/10 second */
499 	cp->nr_up = 0;
500 	if (cp->view.dev && !timer_pending(&cp->timer))
501 		con3270_set_timer(cp, HZ/10);
502 	spin_unlock_irqrestore(&cp->view.lock,flags);
503 }
504 
505 static struct tty_driver *
506 con3270_device(struct console *c, int *index)
507 {
508 	*index = c->index;
509 	return tty3270_driver;
510 }
511 
512 /*
513  * Wait for end of write request.
514  */
515 static void
516 con3270_wait_write(struct con3270 *cp)
517 {
518 	while (!cp->write) {
519 		raw3270_wait_cons_dev(cp->view.dev);
520 		barrier();
521 	}
522 }
523 
524 /*
525  * panic() calls con3270_flush through a panic_notifier
526  * before the system enters a disabled, endless loop.
527  */
528 static void
529 con3270_flush(void)
530 {
531 	struct con3270 *cp;
532 	unsigned long flags;
533 
534 	cp = condev;
535 	if (!cp->view.dev)
536 		return;
537 	raw3270_pm_unfreeze(&cp->view);
538 	raw3270_activate_view(&cp->view);
539 	spin_lock_irqsave(&cp->view.lock, flags);
540 	con3270_wait_write(cp);
541 	cp->nr_up = 0;
542 	con3270_rebuild_update(cp);
543 	con3270_update_status(cp);
544 	while (cp->update_flags != 0) {
545 		spin_unlock_irqrestore(&cp->view.lock, flags);
546 		con3270_update(cp);
547 		spin_lock_irqsave(&cp->view.lock, flags);
548 		con3270_wait_write(cp);
549 	}
550 	spin_unlock_irqrestore(&cp->view.lock, flags);
551 }
552 
553 static int con3270_notify(struct notifier_block *self,
554 			  unsigned long event, void *data)
555 {
556 	con3270_flush();
557 	return NOTIFY_OK;
558 }
559 
560 static struct notifier_block on_panic_nb = {
561 	.notifier_call = con3270_notify,
562 	.priority = 0,
563 };
564 
565 static struct notifier_block on_reboot_nb = {
566 	.notifier_call = con3270_notify,
567 	.priority = 0,
568 };
569 
570 /*
571  *  The console structure for the 3270 console
572  */
573 static struct console con3270 = {
574 	.name	 = "tty3270",
575 	.write	 = con3270_write,
576 	.device	 = con3270_device,
577 	.flags	 = CON_PRINTBUFFER,
578 };
579 
580 /*
581  * 3270 console initialization code called from console_init().
582  */
583 static int __init
584 con3270_init(void)
585 {
586 	struct raw3270 *rp;
587 	void *cbuf;
588 	int i;
589 
590 	/* Check if 3270 is to be the console */
591 	if (!CONSOLE_IS_3270)
592 		return -ENODEV;
593 
594 	/* Set the console mode for VM */
595 	if (MACHINE_IS_VM) {
596 		cpcmd("TERM CONMODE 3270", NULL, 0, NULL);
597 		cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
598 	}
599 
600 	rp = raw3270_setup_console();
601 	if (IS_ERR(rp))
602 		return PTR_ERR(rp);
603 
604 	condev = kzalloc(sizeof(struct con3270), GFP_KERNEL | GFP_DMA);
605 	condev->view.dev = rp;
606 
607 	condev->read = raw3270_request_alloc(0);
608 	condev->read->callback = con3270_read_callback;
609 	condev->read->callback_data = condev;
610 	condev->write = raw3270_request_alloc(CON3270_OUTPUT_BUFFER_SIZE);
611 	condev->kreset = raw3270_request_alloc(1);
612 
613 	INIT_LIST_HEAD(&condev->lines);
614 	INIT_LIST_HEAD(&condev->update);
615 	setup_timer(&condev->timer, (void (*)(unsigned long)) con3270_update,
616 		    (unsigned long) condev);
617 	tasklet_init(&condev->readlet,
618 		     (void (*)(unsigned long)) con3270_read_tasklet,
619 		     (unsigned long) condev->read);
620 
621 	raw3270_add_view(&condev->view, &con3270_fn, 1);
622 
623 	INIT_LIST_HEAD(&condev->freemem);
624 	for (i = 0; i < CON3270_STRING_PAGES; i++) {
625 		cbuf = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
626 		add_string_memory(&condev->freemem, cbuf, PAGE_SIZE);
627 	}
628 	condev->cline = alloc_string(&condev->freemem, condev->view.cols);
629 	condev->cline->len = 0;
630 	con3270_create_status(condev);
631 	condev->input = alloc_string(&condev->freemem, 80);
632 	atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
633 	register_reboot_notifier(&on_reboot_nb);
634 	register_console(&con3270);
635 	return 0;
636 }
637 
638 console_initcall(con3270_init);
639