1/* Serialport functions for debugging
2 *
3 * Copyright (c) 2000-2007 Axis Communications AB
4 *
5 * Authors:  Bjorn Wesen
6 *
7 * Exports:
8 *    console_print_etrax(char *buf)
9 *    int getDebugChar()
10 *    putDebugChar(int)
11 *    enableDebugIRQ()
12 *    init_etrax_debug()
13 *
14 */
15
16#include <linux/console.h>
17#include <linux/init.h>
18#include <linux/major.h>
19#include <linux/delay.h>
20#include <linux/tty.h>
21#include <arch/svinto.h>
22
23extern void reset_watchdog(void);
24
25struct dbg_port
26{
27  unsigned int index;
28  const volatile unsigned* read;
29  volatile char* write;
30  volatile unsigned* xoff;
31  volatile char* baud;
32  volatile char* tr_ctrl;
33  volatile char* rec_ctrl;
34  unsigned long irq;
35  unsigned int started;
36  unsigned long baudrate;
37  unsigned char parity;
38  unsigned int bits;
39};
40
41struct dbg_port ports[]=
42{
43  {
44    0,
45    R_SERIAL0_READ,
46    R_SERIAL0_TR_DATA,
47    R_SERIAL0_XOFF,
48    R_SERIAL0_BAUD,
49    R_SERIAL0_TR_CTRL,
50    R_SERIAL0_REC_CTRL,
51    IO_STATE(R_IRQ_MASK1_SET, ser0_data, set),
52    0,
53    115200,
54    'N',
55    8
56  },
57  {
58    1,
59    R_SERIAL1_READ,
60    R_SERIAL1_TR_DATA,
61    R_SERIAL1_XOFF,
62    R_SERIAL1_BAUD,
63    R_SERIAL1_TR_CTRL,
64    R_SERIAL1_REC_CTRL,
65    IO_STATE(R_IRQ_MASK1_SET, ser1_data, set),
66    0,
67    115200,
68    'N',
69    8
70  },
71  {
72    2,
73    R_SERIAL2_READ,
74    R_SERIAL2_TR_DATA,
75    R_SERIAL2_XOFF,
76    R_SERIAL2_BAUD,
77    R_SERIAL2_TR_CTRL,
78    R_SERIAL2_REC_CTRL,
79    IO_STATE(R_IRQ_MASK1_SET, ser2_data, set),
80    0,
81    115200,
82    'N',
83    8
84  },
85  {
86    3,
87    R_SERIAL3_READ,
88    R_SERIAL3_TR_DATA,
89    R_SERIAL3_XOFF,
90    R_SERIAL3_BAUD,
91    R_SERIAL3_TR_CTRL,
92    R_SERIAL3_REC_CTRL,
93    IO_STATE(R_IRQ_MASK1_SET, ser3_data, set),
94    0,
95    115200,
96    'N',
97    8
98  }
99};
100
101#ifdef CONFIG_ETRAX_SERIAL
102extern struct tty_driver *serial_driver;
103#endif
104
105struct dbg_port* port =
106#if defined(CONFIG_ETRAX_DEBUG_PORT0)
107  &ports[0];
108#elif defined(CONFIG_ETRAX_DEBUG_PORT1)
109  &ports[1];
110#elif defined(CONFIG_ETRAX_DEBUG_PORT2)
111  &ports[2];
112#elif defined(CONFIG_ETRAX_DEBUG_PORT3)
113  &ports[3];
114#else
115  NULL;
116#endif
117
118static struct dbg_port* kgdb_port =
119#if defined(CONFIG_ETRAX_KGDB_PORT0)
120  &ports[0];
121#elif defined(CONFIG_ETRAX_KGDB_PORT1)
122  &ports[1];
123#elif defined(CONFIG_ETRAX_KGDB_PORT2)
124  &ports[2];
125#elif defined(CONFIG_ETRAX_KGDB_PORT3)
126  &ports[3];
127#else
128  NULL;
129#endif
130
131static void
132start_port(struct dbg_port* p)
133{
134	unsigned long rec_ctrl = 0;
135	unsigned long tr_ctrl = 0;
136
137	if (!p)
138		return;
139
140	if (p->started)
141		return;
142	p->started = 1;
143
144	if (p->index == 0)
145	{
146		genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma6);
147		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma6, unused);
148	}
149	else if (p->index == 1)
150	{
151		genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma8);
152		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma8, usb);
153	}
154	else if (p->index == 2)
155	{
156		genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma2);
157		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma2, par0);
158		genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma3);
159		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma3, par0);
160		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, ser2, select);
161	}
162	else
163	{
164		genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma4);
165		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma4, par1);
166		genconfig_shadow &= ~IO_MASK(R_GEN_CONFIG, dma5);
167		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma5, par1);
168		genconfig_shadow |= IO_STATE(R_GEN_CONFIG, ser3, select);
169	}
170
171	*R_GEN_CONFIG = genconfig_shadow;
172
173	*p->xoff =
174		IO_STATE(R_SERIAL0_XOFF, tx_stop, enable) |
175		IO_STATE(R_SERIAL0_XOFF, auto_xoff, disable) |
176		IO_FIELD(R_SERIAL0_XOFF, xoff_char, 0);
177
178	switch (p->baudrate)
179	{
180	case 0:
181	case 115200:
182		*p->baud =
183		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c115k2Hz) |
184		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c115k2Hz);
185		break;
186	case 1200:
187		*p->baud =
188		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c1200Hz) |
189		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c1200Hz);
190		break;
191	case 2400:
192		*p->baud =
193		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c2400Hz) |
194		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c2400Hz);
195		break;
196	case 4800:
197		*p->baud =
198		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c4800Hz) |
199		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c4800Hz);
200		break;
201	case 9600:
202		*p->baud =
203		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c9600Hz) |
204		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c9600Hz);
205		  break;
206	case 19200:
207		*p->baud =
208		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c19k2Hz) |
209		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c19k2Hz);
210		 break;
211	case 38400:
212		*p->baud =
213		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c38k4Hz) |
214		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c38k4Hz);
215		break;
216	case 57600:
217		*p->baud =
218		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c57k6Hz) |
219		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c57k6Hz);
220		break;
221	default:
222		*p->baud =
223		  IO_STATE(R_SERIAL0_BAUD, tr_baud, c115k2Hz) |
224		  IO_STATE(R_SERIAL0_BAUD, rec_baud, c115k2Hz);
225		  break;
226        }
227
228	if (p->parity == 'E') {
229		rec_ctrl =
230		  IO_STATE(R_SERIAL0_REC_CTRL, rec_par, even) |
231		  IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, enable);
232		tr_ctrl =
233		  IO_STATE(R_SERIAL0_TR_CTRL, tr_par, even) |
234		  IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, enable);
235	} else if (p->parity == 'O') {
236		rec_ctrl =
237		  IO_STATE(R_SERIAL0_REC_CTRL, rec_par, odd) |
238		  IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, enable);
239		tr_ctrl =
240		  IO_STATE(R_SERIAL0_TR_CTRL, tr_par, odd) |
241		  IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, enable);
242	} else {
243		rec_ctrl =
244		  IO_STATE(R_SERIAL0_REC_CTRL, rec_par, even) |
245		  IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, disable);
246		tr_ctrl =
247		  IO_STATE(R_SERIAL0_TR_CTRL, tr_par, even) |
248		  IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, disable);
249	}
250	if (p->bits == 7)
251	{
252		rec_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_bitnr, rec_7bit);
253		tr_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_bitnr, tr_7bit);
254	}
255	else
256	{
257		rec_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_bitnr, rec_8bit);
258		tr_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_bitnr, tr_8bit);
259	}
260
261	*p->rec_ctrl =
262		IO_STATE(R_SERIAL0_REC_CTRL, dma_err, stop) |
263		IO_STATE(R_SERIAL0_REC_CTRL, rec_enable, enable) |
264		IO_STATE(R_SERIAL0_REC_CTRL, rts_, active) |
265		IO_STATE(R_SERIAL0_REC_CTRL, sampling, middle) |
266		IO_STATE(R_SERIAL0_REC_CTRL, rec_stick_par, normal) |
267		rec_ctrl;
268
269	*p->tr_ctrl =
270		IO_FIELD(R_SERIAL0_TR_CTRL, txd, 0) |
271		IO_STATE(R_SERIAL0_TR_CTRL, tr_enable, enable) |
272		IO_STATE(R_SERIAL0_TR_CTRL, auto_cts, disabled) |
273		IO_STATE(R_SERIAL0_TR_CTRL, stop_bits, one_bit) |
274		IO_STATE(R_SERIAL0_TR_CTRL, tr_stick_par, normal) |
275		tr_ctrl;
276}
277
278static void
279console_write_direct(struct console *co, const char *buf, unsigned int len)
280{
281	int i;
282	unsigned long flags;
283
284        if (!port)
285		return;
286
287	local_irq_save(flags);
288
289	/* Send data */
290	for (i = 0; i < len; i++) {
291		/* LF -> CRLF */
292		if (buf[i] == '\n') {
293			while (!(*port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
294			;
295			*port->write = '\r';
296		}
297		/* Wait until transmitter is ready and send.*/
298		while (!(*port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
299			;
300		*port->write = buf[i];
301	}
302
303	/*
304	 * Feed the watchdog, otherwise it will reset the chip during boot.
305	 * The time to send an ordinary boot message line (10-90 chars)
306	 * varies between 1-8ms at 115200. What makes up for the additional
307	 * 90ms that allows the watchdog to bite?
308	*/
309	reset_watchdog();
310
311	local_irq_restore(flags);
312}
313
314static void
315console_write(struct console *co, const char *buf, unsigned int len)
316{
317	if (!port)
318		return;
319
320        console_write_direct(co, buf, len);
321}
322
323/* legacy function */
324
325void
326console_print_etrax(const char *buf)
327{
328	console_write(NULL, buf, strlen(buf));
329}
330
331/* Use polling to get a single character FROM the debug port */
332
333int
334getDebugChar(void)
335{
336	unsigned long readval;
337
338	if (!kgdb_port)
339		return 0;
340
341	do {
342		readval = *kgdb_port->read;
343	} while (!(readval & IO_MASK(R_SERIAL0_READ, data_avail)));
344
345	return (readval & IO_MASK(R_SERIAL0_READ, data_in));
346}
347
348/* Use polling to put a single character to the debug port */
349
350void
351putDebugChar(int val)
352{
353	if (!kgdb_port)
354		return;
355
356	while (!(*kgdb_port->read & IO_MASK(R_SERIAL0_READ, tr_ready)))
357		;
358	*kgdb_port->write = val;
359}
360
361/* Enable irq for receiving chars on the debug port, used by kgdb */
362
363void
364enableDebugIRQ(void)
365{
366	if (!kgdb_port)
367		return;
368
369	*R_IRQ_MASK1_SET = kgdb_port->irq;
370	/* use R_VECT_MASK directly, since we really bypass Linux normal
371	 * IRQ handling in kgdb anyway, we don't need to use enable_irq
372	 */
373	*R_VECT_MASK_SET = IO_STATE(R_VECT_MASK_SET, serial, set);
374
375	*kgdb_port->rec_ctrl = IO_STATE(R_SERIAL0_REC_CTRL, rec_enable, enable);
376}
377
378static int __init
379console_setup(struct console *co, char *options)
380{
381	char* s;
382
383	if (options) {
384		port = &ports[co->index];
385		port->baudrate = 115200;
386                port->parity = 'N';
387                port->bits = 8;
388		port->baudrate = simple_strtoul(options, NULL, 10);
389		s = options;
390		while(*s >= '0' && *s <= '9')
391			s++;
392		if (*s) port->parity = *s++;
393		if (*s) port->bits   = *s++ - '0';
394		port->started = 0;
395		start_port(0);
396	}
397	return 0;
398}
399
400
401/* This is a dummy serial device that throws away anything written to it.
402 * This is used when no debug output is wanted.
403 */
404static struct tty_driver dummy_driver;
405
406static int dummy_open(struct tty_struct *tty, struct file * filp)
407{
408	return 0;
409}
410
411static void dummy_close(struct tty_struct *tty, struct file * filp)
412{
413}
414
415static int dummy_write(struct tty_struct * tty,
416                       const unsigned char *buf, int count)
417{
418	return count;
419}
420
421static int dummy_write_room(struct tty_struct *tty)
422{
423	return 8192;
424}
425
426static const struct tty_operations dummy_ops = {
427	.open = dummy_open,
428	.close = dummy_close,
429	.write = dummy_write,
430	.write_room = dummy_write_room,
431};
432
433void __init
434init_dummy_console(void)
435{
436	memset(&dummy_driver, 0, sizeof(struct tty_driver));
437	dummy_driver.driver_name = "serial";
438	dummy_driver.name = "ttyS";
439	dummy_driver.major = TTY_MAJOR;
440	dummy_driver.minor_start = 68;
441	dummy_driver.num = 1;       /* etrax100 has 4 serial ports */
442	dummy_driver.type = TTY_DRIVER_TYPE_SERIAL;
443	dummy_driver.subtype = SERIAL_TYPE_NORMAL;
444	dummy_driver.init_termios = tty_std_termios;
445	/* Normally B9600 default... */
446	dummy_driver.init_termios.c_cflag =
447		B115200 | CS8 | CREAD | HUPCL | CLOCAL;
448	dummy_driver.flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
449	dummy_driver.init_termios.c_ispeed = 115200;
450	dummy_driver.init_termios.c_ospeed = 115200;
451
452	dummy_driver.ops = &dummy_ops;
453	if (tty_register_driver(&dummy_driver))
454		panic("Couldn't register dummy serial driver\n");
455}
456
457static struct tty_driver*
458etrax_console_device(struct console* co, int *index)
459{
460	if (port)
461		*index = port->index;
462	else
463		*index = 0;
464#ifdef CONFIG_ETRAX_SERIAL
465        return port ? serial_driver : &dummy_driver;
466#else
467	return &dummy_driver;
468#endif
469}
470
471static struct console sercons = {
472	name : "ttyS",
473	write: console_write,
474	read : NULL,
475	device : etrax_console_device,
476	unblank : NULL,
477	setup : console_setup,
478	flags : CON_PRINTBUFFER,
479	index : -1,
480	cflag : 0,
481	next : NULL
482};
483static struct console sercons0 = {
484	name : "ttyS",
485	write: console_write,
486	read : NULL,
487	device : etrax_console_device,
488	unblank : NULL,
489	setup : console_setup,
490	flags : CON_PRINTBUFFER,
491	index : 0,
492	cflag : 0,
493	next : NULL
494};
495
496static struct console sercons1 = {
497	name : "ttyS",
498	write: console_write,
499	read : NULL,
500	device : etrax_console_device,
501	unblank : NULL,
502	setup : console_setup,
503	flags : CON_PRINTBUFFER,
504	index : 1,
505	cflag : 0,
506	next : NULL
507};
508static struct console sercons2 = {
509	name : "ttyS",
510	write: console_write,
511	read : NULL,
512	device : etrax_console_device,
513	unblank : NULL,
514	setup : console_setup,
515	flags : CON_PRINTBUFFER,
516	index : 2,
517	cflag : 0,
518	next : NULL
519};
520static struct console sercons3 = {
521	name : "ttyS",
522	write: console_write,
523	read : NULL,
524	device : etrax_console_device,
525	unblank : NULL,
526	setup : console_setup,
527	flags : CON_PRINTBUFFER,
528	index : 3,
529	cflag : 0,
530	next : NULL
531};
532/*
533 *      Register console (for printk's etc)
534 */
535
536int __init
537init_etrax_debug(void)
538{
539	static int first = 1;
540
541	if (!first) {
542		unregister_console(&sercons);
543		register_console(&sercons0);
544		register_console(&sercons1);
545		register_console(&sercons2);
546		register_console(&sercons3);
547                init_dummy_console();
548		return 0;
549	}
550
551	first = 0;
552	register_console(&sercons);
553	start_port(port);
554#ifdef CONFIG_ETRAX_KGDB
555	start_port(kgdb_port);
556#endif
557	return 0;
558}
559__initcall(init_etrax_debug);
560