1/*
2 *  drivers/s390/char/con3270.c
3 *    IBM/3270 Driver - console view.
4 *
5 *  Author(s):
6 *    Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
7 *    Rewritten for 2.5 by Martin Schwidefsky <schwidefsky@de.ibm.com>
8 *	-- Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
9 */
10
11#include <linux/bootmem.h>
12#include <linux/console.h>
13#include <linux/init.h>
14#include <linux/interrupt.h>
15#include <linux/list.h>
16#include <linux/types.h>
17#include <linux/err.h>
18
19#include <asm/ccwdev.h>
20#include <asm/cio.h>
21#include <asm/cpcmd.h>
22#include <asm/ebcdic.h>
23
24#include "raw3270.h"
25#include "ctrlchar.h"
26
27#define CON3270_OUTPUT_BUFFER_SIZE 1024
28#define CON3270_STRING_PAGES 4
29
30static struct raw3270_fn con3270_fn;
31
32/*
33 * Main 3270 console view data structure.
34 */
35struct con3270 {
36	struct raw3270_view view;
37	spinlock_t lock;
38	struct list_head freemem;	/* list of free memory for strings. */
39
40	/* Output stuff. */
41	struct list_head lines;		/* list of lines. */
42	struct list_head update;	/* list of lines to update. */
43	int line_nr;			/* line number for next update. */
44	int nr_lines;			/* # lines in list. */
45	int nr_up;			/* # lines up in history. */
46	unsigned long update_flags;	/* Update indication bits. */
47	struct string *cline;		/* current output line. */
48	struct string *status;		/* last line of display. */
49	struct raw3270_request *write;	/* single write request. */
50	struct timer_list timer;
51
52	/* Input stuff. */
53	struct string *input;		/* input string for read request. */
54	struct raw3270_request *read;	/* single read request. */
55	struct raw3270_request *kreset;	/* single keyboard reset request. */
56	struct tasklet_struct readlet;	/* tasklet to issue read request. */
57};
58
59static struct con3270 *condev;
60
61/* con3270->update_flags. See con3270_update for details. */
62#define CON_UPDATE_ERASE	1	/* Use EWRITEA instead of WRITE. */
63#define CON_UPDATE_LIST		2	/* Update lines in tty3270->update. */
64#define CON_UPDATE_STATUS	4	/* Update status line. */
65#define CON_UPDATE_ALL		7
66
67static void con3270_update(struct con3270 *);
68
69/*
70 * Setup timeout for a device. On timeout trigger an update.
71 */
72static void con3270_set_timer(struct con3270 *cp, int expires)
73{
74	if (expires == 0) {
75		if (timer_pending(&cp->timer))
76			del_timer(&cp->timer);
77		return;
78	}
79	if (timer_pending(&cp->timer) &&
80	    mod_timer(&cp->timer, jiffies + expires))
81		return;
82	cp->timer.function = (void (*)(unsigned long)) con3270_update;
83	cp->timer.data = (unsigned long) cp;
84	cp->timer.expires = jiffies + expires;
85	add_timer(&cp->timer);
86}
87
88/*
89 * The status line is the last line of the screen. It shows the string
90 * "console view" in the lower left corner and "Running"/"More..."/"Holding"
91 * in the lower right corner of the screen.
92 */
93static void
94con3270_update_status(struct con3270 *cp)
95{
96	char *str;
97
98	str = (cp->nr_up != 0) ? "History" : "Running";
99	memcpy(cp->status->string + 24, str, 7);
100	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
101	cp->update_flags |= CON_UPDATE_STATUS;
102}
103
104static void
105con3270_create_status(struct con3270 *cp)
106{
107	static const unsigned char blueprint[] =
108		{ TO_SBA, 0, 0, TO_SF,TF_LOG,TO_SA,TAT_COLOR, TAC_GREEN,
109		  'c','o','n','s','o','l','e',' ','v','i','e','w',
110		  TO_RA,0,0,0,'R','u','n','n','i','n','g',TO_SF,TF_LOG };
111
112	cp->status = alloc_string(&cp->freemem, sizeof(blueprint));
113	/* Copy blueprint to status line */
114	memcpy(cp->status->string, blueprint, sizeof(blueprint));
115	/* Set TO_RA addresses. */
116	raw3270_buffer_address(cp->view.dev, cp->status->string + 1,
117			       cp->view.cols * (cp->view.rows - 1));
118	raw3270_buffer_address(cp->view.dev, cp->status->string + 21,
119			       cp->view.cols * cp->view.rows - 8);
120	/* Convert strings to ebcdic. */
121	codepage_convert(cp->view.ascebc, cp->status->string + 8, 12);
122	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
123}
124
125/*
126 * Set output offsets to 3270 datastream fragment of a console string.
127 */
128static void
129con3270_update_string(struct con3270 *cp, struct string *s, int nr)
130{
131	if (s->len >= cp->view.cols - 5)
132		return;
133	raw3270_buffer_address(cp->view.dev, s->string + s->len - 3,
134			       cp->view.cols * (nr + 1));
135}
136
137/*
138 * Rebuild update list to print all lines.
139 */
140static void
141con3270_rebuild_update(struct con3270 *cp)
142{
143	struct string *s, *n;
144	int nr;
145
146	/*
147	 * Throw away update list and create a new one,
148	 * containing all lines that will fit on the screen.
149	 */
150	list_for_each_entry_safe(s, n, &cp->update, update)
151		list_del_init(&s->update);
152	nr = cp->view.rows - 2 + cp->nr_up;
153	list_for_each_entry_reverse(s, &cp->lines, list) {
154		if (nr < cp->view.rows - 1)
155			list_add(&s->update, &cp->update);
156		if (--nr < 0)
157			break;
158	}
159	cp->line_nr = 0;
160	cp->update_flags |= CON_UPDATE_LIST;
161}
162
163/*
164 * Alloc string for size bytes. Free strings from history if necessary.
165 */
166static struct string *
167con3270_alloc_string(struct con3270 *cp, size_t size)
168{
169	struct string *s, *n;
170
171	s = alloc_string(&cp->freemem, size);
172	if (s)
173		return s;
174	list_for_each_entry_safe(s, n, &cp->lines, list) {
175		list_del(&s->list);
176		if (!list_empty(&s->update))
177			list_del(&s->update);
178		cp->nr_lines--;
179		if (free_string(&cp->freemem, s) >= size)
180			break;
181	}
182	s = alloc_string(&cp->freemem, size);
183	BUG_ON(!s);
184	if (cp->nr_up != 0 && cp->nr_up + cp->view.rows > cp->nr_lines) {
185		cp->nr_up = cp->nr_lines - cp->view.rows + 1;
186		con3270_rebuild_update(cp);
187		con3270_update_status(cp);
188	}
189	return s;
190}
191
192/*
193 * Write completion callback.
194 */
195static void
196con3270_write_callback(struct raw3270_request *rq, void *data)
197{
198	raw3270_request_reset(rq);
199	xchg(&((struct con3270 *) rq->view)->write, rq);
200}
201
202/*
203 * Update console display.
204 */
205static void
206con3270_update(struct con3270 *cp)
207{
208	struct raw3270_request *wrq;
209	char wcc, prolog[6];
210	unsigned long flags;
211	unsigned long updated;
212	struct string *s, *n;
213	int rc;
214
215	if (cp->view.dev)
216		raw3270_activate_view(&cp->view);
217
218	wrq = xchg(&cp->write, 0);
219	if (!wrq) {
220		con3270_set_timer(cp, 1);
221		return;
222	}
223
224	spin_lock_irqsave(&cp->view.lock, flags);
225	updated = 0;
226	if (cp->update_flags & CON_UPDATE_ERASE) {
227		/* Use erase write alternate to initialize display. */
228		raw3270_request_set_cmd(wrq, TC_EWRITEA);
229		updated |= CON_UPDATE_ERASE;
230	} else
231		raw3270_request_set_cmd(wrq, TC_WRITE);
232
233	wcc = TW_NONE;
234	raw3270_request_add_data(wrq, &wcc, 1);
235
236	/*
237	 * Update status line.
238	 */
239	if (cp->update_flags & CON_UPDATE_STATUS)
240		if (raw3270_request_add_data(wrq, cp->status->string,
241					     cp->status->len) == 0)
242			updated |= CON_UPDATE_STATUS;
243
244	if (cp->update_flags & CON_UPDATE_LIST) {
245		prolog[0] = TO_SBA;
246		prolog[3] = TO_SA;
247		prolog[4] = TAT_COLOR;
248		prolog[5] = TAC_TURQ;
249		raw3270_buffer_address(cp->view.dev, prolog + 1,
250				       cp->view.cols * cp->line_nr);
251		raw3270_request_add_data(wrq, prolog, 6);
252		/* Write strings in the update list to the screen. */
253		list_for_each_entry_safe(s, n, &cp->update, update) {
254			if (s != cp->cline)
255				con3270_update_string(cp, s, cp->line_nr);
256			if (raw3270_request_add_data(wrq, s->string,
257						     s->len) != 0)
258				break;
259			list_del_init(&s->update);
260			if (s != cp->cline)
261				cp->line_nr++;
262		}
263		if (list_empty(&cp->update))
264			updated |= CON_UPDATE_LIST;
265	}
266	wrq->callback = con3270_write_callback;
267	rc = raw3270_start(&cp->view, wrq);
268	if (rc == 0) {
269		cp->update_flags &= ~updated;
270		if (cp->update_flags)
271			con3270_set_timer(cp, 1);
272	} else {
273		raw3270_request_reset(wrq);
274		xchg(&cp->write, wrq);
275	}
276	spin_unlock_irqrestore(&cp->view.lock, flags);
277}
278
279/*
280 * Read tasklet.
281 */
282static void
283con3270_read_tasklet(struct raw3270_request *rrq)
284{
285	static char kreset_data = TW_KR;
286	struct con3270 *cp;
287	unsigned long flags;
288	int nr_up, deactivate;
289
290	cp = (struct con3270 *) rrq->view;
291	spin_lock_irqsave(&cp->view.lock, flags);
292	nr_up = cp->nr_up;
293	deactivate = 0;
294	/* Check aid byte. */
295	switch (cp->input->string[0]) {
296	case 0x7d:	/* enter: jump to bottom. */
297		nr_up = 0;
298		break;
299	case 0xf3:	/* PF3: deactivate the console view. */
300		deactivate = 1;
301		break;
302	case 0x6d:	/* clear: start from scratch. */
303		con3270_rebuild_update(cp);
304		cp->update_flags = CON_UPDATE_ALL;
305		con3270_set_timer(cp, 1);
306		break;
307	case 0xf7:	/* PF7: do a page up in the console log. */
308		nr_up += cp->view.rows - 2;
309		if (nr_up + cp->view.rows - 1 > cp->nr_lines) {
310			nr_up = cp->nr_lines - cp->view.rows + 1;
311			if (nr_up < 0)
312				nr_up = 0;
313		}
314		break;
315	case 0xf8:	/* PF8: do a page down in the console log. */
316		nr_up -= cp->view.rows - 2;
317		if (nr_up < 0)
318			nr_up = 0;
319		break;
320	}
321	if (nr_up != cp->nr_up) {
322		cp->nr_up = nr_up;
323		con3270_rebuild_update(cp);
324		con3270_update_status(cp);
325		con3270_set_timer(cp, 1);
326	}
327	spin_unlock_irqrestore(&cp->view.lock, flags);
328
329	/* Start keyboard reset command. */
330	raw3270_request_reset(cp->kreset);
331	raw3270_request_set_cmd(cp->kreset, TC_WRITE);
332	raw3270_request_add_data(cp->kreset, &kreset_data, 1);
333	raw3270_start(&cp->view, cp->kreset);
334
335	if (deactivate)
336		raw3270_deactivate_view(&cp->view);
337
338	raw3270_request_reset(rrq);
339	xchg(&cp->read, rrq);
340	raw3270_put_view(&cp->view);
341}
342
343/*
344 * Read request completion callback.
345 */
346static void
347con3270_read_callback(struct raw3270_request *rq, void *data)
348{
349	raw3270_get_view(rq->view);
350	/* Schedule tasklet to pass input to tty. */
351	tasklet_schedule(&((struct con3270 *) rq->view)->readlet);
352}
353
354/*
355 * Issue a read request. Called only from interrupt function.
356 */
357static void
358con3270_issue_read(struct con3270 *cp)
359{
360	struct raw3270_request *rrq;
361	int rc;
362
363	rrq = xchg(&cp->read, 0);
364	if (!rrq)
365		/* Read already scheduled. */
366		return;
367	rrq->callback = con3270_read_callback;
368	rrq->callback_data = cp;
369	raw3270_request_set_cmd(rrq, TC_READMOD);
370	raw3270_request_set_data(rrq, cp->input->string, cp->input->len);
371	/* Issue the read modified request. */
372	rc = raw3270_start_irq(&cp->view, rrq);
373	if (rc)
374		raw3270_request_reset(rrq);
375}
376
377/*
378 * Switch to the console view.
379 */
380static int
381con3270_activate(struct raw3270_view *view)
382{
383	unsigned long flags;
384	struct con3270 *cp;
385
386	cp = (struct con3270 *) view;
387	spin_lock_irqsave(&cp->view.lock, flags);
388	cp->nr_up = 0;
389	con3270_rebuild_update(cp);
390	con3270_update_status(cp);
391	cp->update_flags = CON_UPDATE_ALL;
392	con3270_set_timer(cp, 1);
393	spin_unlock_irqrestore(&cp->view.lock, flags);
394	return 0;
395}
396
397static void
398con3270_deactivate(struct raw3270_view *view)
399{
400	unsigned long flags;
401	struct con3270 *cp;
402
403	cp = (struct con3270 *) view;
404	spin_lock_irqsave(&cp->view.lock, flags);
405	del_timer(&cp->timer);
406	spin_unlock_irqrestore(&cp->view.lock, flags);
407}
408
409static int
410con3270_irq(struct con3270 *cp, struct raw3270_request *rq, struct irb *irb)
411{
412	/* Handle ATTN. Schedule tasklet to read aid. */
413	if (irb->scsw.dstat & DEV_STAT_ATTENTION)
414		con3270_issue_read(cp);
415
416	if (rq) {
417		if (irb->scsw.dstat & DEV_STAT_UNIT_CHECK)
418			rq->rc = -EIO;
419		else
420			/* Normal end. Copy residual count. */
421			rq->rescnt = irb->scsw.count;
422	}
423	return RAW3270_IO_DONE;
424}
425
426/* Console view to a 3270 device. */
427static struct raw3270_fn con3270_fn = {
428	.activate = con3270_activate,
429	.deactivate = con3270_deactivate,
430	.intv = (void *) con3270_irq
431};
432
433static inline void
434con3270_cline_add(struct con3270 *cp)
435{
436	if (!list_empty(&cp->cline->list))
437		/* Already added. */
438		return;
439	list_add_tail(&cp->cline->list, &cp->lines);
440	cp->nr_lines++;
441	con3270_rebuild_update(cp);
442}
443
444static inline void
445con3270_cline_insert(struct con3270 *cp, unsigned char c)
446{
447	cp->cline->string[cp->cline->len++] =
448		cp->view.ascebc[(c < ' ') ? ' ' : c];
449	if (list_empty(&cp->cline->update)) {
450		list_add_tail(&cp->cline->update, &cp->update);
451		cp->update_flags |= CON_UPDATE_LIST;
452	}
453}
454
455static inline void
456con3270_cline_end(struct con3270 *cp)
457{
458	struct string *s;
459	unsigned int size;
460
461	/* Copy cline. */
462	size = (cp->cline->len < cp->view.cols - 5) ?
463		cp->cline->len + 4 : cp->view.cols;
464	s = con3270_alloc_string(cp, size);
465	memcpy(s->string, cp->cline->string, cp->cline->len);
466	if (s->len < cp->view.cols - 5) {
467		s->string[s->len - 4] = TO_RA;
468		s->string[s->len - 1] = 0;
469	} else {
470		while (--size > cp->cline->len)
471			s->string[size] = cp->view.ascebc[' '];
472	}
473	/* Replace cline with allocated line s and reset cline. */
474	list_add(&s->list, &cp->cline->list);
475	list_del_init(&cp->cline->list);
476	if (!list_empty(&cp->cline->update)) {
477		list_add(&s->update, &cp->cline->update);
478		list_del_init(&cp->cline->update);
479	}
480	cp->cline->len = 0;
481}
482
483/*
484 * Write a string to the 3270 console
485 */
486static void
487con3270_write(struct console *co, const char *str, unsigned int count)
488{
489	struct con3270 *cp;
490	unsigned long flags;
491	unsigned char c;
492
493	cp = condev;
494	spin_lock_irqsave(&cp->view.lock, flags);
495	while (count-- > 0) {
496		c = *str++;
497		if (cp->cline->len == 0)
498			con3270_cline_add(cp);
499		if (c != '\n')
500			con3270_cline_insert(cp, c);
501		if (c == '\n' || cp->cline->len >= cp->view.cols)
502			con3270_cline_end(cp);
503	}
504	/* Setup timer to output current console buffer after 1/10 second */
505	if (cp->view.dev && !timer_pending(&cp->timer))
506		con3270_set_timer(cp, HZ/10);
507	spin_unlock_irqrestore(&cp->view.lock,flags);
508}
509
510extern struct tty_driver *tty3270_driver;
511
512static struct tty_driver *
513con3270_device(struct console *c, int *index)
514{
515	*index = c->index;
516	return tty3270_driver;
517}
518
519/*
520 * Wait for end of write request.
521 */
522static void
523con3270_wait_write(struct con3270 *cp)
524{
525	while (!cp->write) {
526		raw3270_wait_cons_dev(cp->view.dev);
527		barrier();
528	}
529}
530
531/*
532 * panic() calls console_unblank before the system enters a
533 * disabled, endless loop.
534 */
535static void
536con3270_unblank(void)
537{
538	struct con3270 *cp;
539	unsigned long flags;
540
541	cp = condev;
542	if (!cp->view.dev)
543		return;
544	spin_lock_irqsave(&cp->view.lock, flags);
545	con3270_wait_write(cp);
546	cp->nr_up = 0;
547	con3270_rebuild_update(cp);
548	con3270_update_status(cp);
549	while (cp->update_flags != 0) {
550		spin_unlock_irqrestore(&cp->view.lock, flags);
551		con3270_update(cp);
552		spin_lock_irqsave(&cp->view.lock, flags);
553		con3270_wait_write(cp);
554	}
555	spin_unlock_irqrestore(&cp->view.lock, flags);
556}
557
558/*
559 *  The console structure for the 3270 console
560 */
561static struct console con3270 = {
562	.name	 = "tty3270",
563	.write	 = con3270_write,
564	.device	 = con3270_device,
565	.unblank = con3270_unblank,
566	.flags	 = CON_PRINTBUFFER,
567};
568
569/*
570 * 3270 console initialization code called from console_init().
571 * NOTE: This is called before kmalloc is available.
572 */
573static int __init
574con3270_init(void)
575{
576	struct ccw_device *cdev;
577	struct raw3270 *rp;
578	void *cbuf;
579	int i;
580
581	/* Check if 3270 is to be the console */
582	if (!CONSOLE_IS_3270)
583		return -ENODEV;
584
585	/* Set the console mode for VM */
586	if (MACHINE_IS_VM) {
587		cpcmd("TERM CONMODE 3270", NULL, 0, NULL);
588		cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
589	}
590
591	cdev = ccw_device_probe_console();
592	if (IS_ERR(cdev))
593		return -ENODEV;
594	rp = raw3270_setup_console(cdev);
595	if (IS_ERR(rp))
596		return PTR_ERR(rp);
597
598	condev = (struct con3270 *) alloc_bootmem_low(sizeof(struct con3270));
599	memset(condev, 0, sizeof(struct con3270));
600	condev->view.dev = rp;
601
602	condev->read = raw3270_request_alloc_bootmem(0);
603	condev->read->callback = con3270_read_callback;
604	condev->read->callback_data = condev;
605	condev->write =
606		raw3270_request_alloc_bootmem(CON3270_OUTPUT_BUFFER_SIZE);
607	condev->kreset = raw3270_request_alloc_bootmem(1);
608
609	INIT_LIST_HEAD(&condev->lines);
610	INIT_LIST_HEAD(&condev->update);
611	init_timer(&condev->timer);
612	tasklet_init(&condev->readlet,
613		     (void (*)(unsigned long)) con3270_read_tasklet,
614		     (unsigned long) condev->read);
615
616	raw3270_add_view(&condev->view, &con3270_fn, 1);
617
618	INIT_LIST_HEAD(&condev->freemem);
619	for (i = 0; i < CON3270_STRING_PAGES; i++) {
620		cbuf = (void *) alloc_bootmem_low_pages(PAGE_SIZE);
621		add_string_memory(&condev->freemem, cbuf, PAGE_SIZE);
622	}
623	condev->cline = alloc_string(&condev->freemem, condev->view.cols);
624	condev->cline->len = 0;
625	con3270_create_status(condev);
626	condev->input = alloc_string(&condev->freemem, 80);
627	register_console(&con3270);
628	return 0;
629}
630
631console_initcall(con3270_init);
632