xref: /rk3399_rockchip-uboot/drivers/serial/serial.c (revision afad40299eea12dfd032b44d04c2d4151d7e9862)
1 /*
2  * (C) Copyright 2004
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 #include <serial.h>
26 #include <stdio_dev.h>
27 #include <post.h>
28 #include <linux/compiler.h>
29 #include <errno.h>
30 
31 DECLARE_GLOBAL_DATA_PTR;
32 
33 static struct serial_device *serial_devices;
34 static struct serial_device *serial_current;
35 
36 /**
37  * serial_null() - Void registration routine of a serial driver
38  *
39  * This routine implements a void registration routine of a serial
40  * driver. The registration routine of a particular driver is aliased
41  * to this empty function in case the driver is not compiled into
42  * U-Boot.
43  */
44 static void serial_null(void)
45 {
46 }
47 
48 /**
49  * serial_initfunc() - Forward declare of driver registration routine
50  * @name:	Name of the real driver registration routine.
51  *
52  * This macro expands onto forward declaration of a driver registration
53  * routine, which is then used below in serial_initialize() function.
54  * The declaration is made weak and aliases to serial_null() so in case
55  * the driver is not compiled in, the function is still declared and can
56  * be used, but aliases to serial_null() and thus is optimized away.
57  */
58 #define serial_initfunc(name)					\
59 	void name(void)						\
60 		__attribute__((weak, alias("serial_null")));
61 
62 serial_initfunc(mpc8xx_serial_initialize);
63 serial_initfunc(ns16550_serial_initialize);
64 serial_initfunc(pxa_serial_initialize);
65 serial_initfunc(s3c24xx_serial_initialize);
66 serial_initfunc(s5p_serial_initialize);
67 serial_initfunc(zynq_serial_initalize);
68 serial_initfunc(bfin_serial_initialize);
69 serial_initfunc(bfin_jtag_initialize);
70 serial_initfunc(mpc512x_serial_initialize);
71 serial_initfunc(uartlite_serial_initialize);
72 serial_initfunc(au1x00_serial_initialize);
73 serial_initfunc(asc_serial_initialize);
74 serial_initfunc(jz_serial_initialize);
75 serial_initfunc(mpc5xx_serial_initialize);
76 serial_initfunc(mpc8220_serial_initialize);
77 serial_initfunc(mpc8260_scc_serial_initialize);
78 serial_initfunc(mpc8260_smc_serial_initialize);
79 serial_initfunc(mpc85xx_serial_initialize);
80 serial_initfunc(iop480_serial_initialize);
81 serial_initfunc(leon2_serial_initialize);
82 serial_initfunc(leon3_serial_initialize);
83 serial_initfunc(marvell_serial_initialize);
84 serial_initfunc(amirix_serial_initialize);
85 serial_initfunc(bmw_serial_initialize);
86 serial_initfunc(cogent_serial_initialize);
87 serial_initfunc(cpci750_serial_initialize);
88 serial_initfunc(evb64260_serial_initialize);
89 serial_initfunc(ml2_serial_initialize);
90 serial_initfunc(sconsole_serial_initialize);
91 serial_initfunc(p3mx_serial_initialize);
92 serial_initfunc(altera_jtag_serial_initialize);
93 serial_initfunc(altera_serial_initialize);
94 serial_initfunc(atmel_serial_initialize);
95 serial_initfunc(lpc32xx_serial_initialize);
96 serial_initfunc(mcf_serial_initialize);
97 serial_initfunc(ns9750_serial_initialize);
98 serial_initfunc(oc_serial_initialize);
99 serial_initfunc(s3c64xx_serial_initialize);
100 serial_initfunc(sandbox_serial_initialize);
101 serial_initfunc(clps7111_serial_initialize);
102 serial_initfunc(imx_serial_initialize);
103 serial_initfunc(ixp_serial_initialize);
104 serial_initfunc(ks8695_serial_initialize);
105 serial_initfunc(lh7a40x_serial_initialize);
106 serial_initfunc(max3100_serial_initialize);
107 serial_initfunc(mxc_serial_initialize);
108 serial_initfunc(netarm_serial_initialize);
109 serial_initfunc(pl01x_serial_initialize);
110 serial_initfunc(s3c44b0_serial_initialize);
111 serial_initfunc(sa1100_serial_initialize);
112 serial_initfunc(sh_serial_initialize);
113 
114 /**
115  * serial_register() - Register serial driver with serial driver core
116  * @dev:	Pointer to the serial driver structure
117  *
118  * This function registers the serial driver supplied via @dev with
119  * serial driver core, thus making U-Boot aware of it and making it
120  * available for U-Boot to use. On platforms that still require manual
121  * relocation of constant variables, relocation of the supplied structure
122  * is performed.
123  */
124 void serial_register(struct serial_device *dev)
125 {
126 #ifdef CONFIG_NEEDS_MANUAL_RELOC
127 	if (dev->start)
128 		dev->start += gd->reloc_off;
129 	if (dev->stop)
130 		dev->stop += gd->reloc_off;
131 	if (dev->setbrg)
132 		dev->setbrg += gd->reloc_off;
133 	if (dev->getc)
134 		dev->getc += gd->reloc_off;
135 	if (dev->tstc)
136 		dev->tstc += gd->reloc_off;
137 	if (dev->putc)
138 		dev->putc += gd->reloc_off;
139 	if (dev->puts)
140 		dev->puts += gd->reloc_off;
141 #endif
142 
143 	dev->next = serial_devices;
144 	serial_devices = dev;
145 }
146 
147 /**
148  * serial_initialize() - Register all compiled-in serial port drivers
149  *
150  * This function registers all serial port drivers that are compiled
151  * into the U-Boot binary with the serial core, thus making them
152  * available to U-Boot to use. Lastly, this function assigns a default
153  * serial port to the serial core. That serial port is then used as a
154  * default output.
155  */
156 void serial_initialize(void)
157 {
158 	mpc8xx_serial_initialize();
159 	ns16550_serial_initialize();
160 	pxa_serial_initialize();
161 	s3c24xx_serial_initialize();
162 	s5p_serial_initialize();
163 	mpc512x_serial_initialize();
164 	bfin_serial_initialize();
165 	bfin_jtag_initialize();
166 	uartlite_serial_initialize();
167 	zynq_serial_initalize();
168 	au1x00_serial_initialize();
169 	asc_serial_initialize();
170 	jz_serial_initialize();
171 	mpc5xx_serial_initialize();
172 	mpc8220_serial_initialize();
173 	mpc8260_scc_serial_initialize();
174 	mpc8260_smc_serial_initialize();
175 	mpc85xx_serial_initialize();
176 	iop480_serial_initialize();
177 	leon2_serial_initialize();
178 	leon3_serial_initialize();
179 	marvell_serial_initialize();
180 	amirix_serial_initialize();
181 	bmw_serial_initialize();
182 	cogent_serial_initialize();
183 	cpci750_serial_initialize();
184 	evb64260_serial_initialize();
185 	ml2_serial_initialize();
186 	sconsole_serial_initialize();
187 	p3mx_serial_initialize();
188 	altera_jtag_serial_initialize();
189 	altera_serial_initialize();
190 	atmel_serial_initialize();
191 	lpc32xx_serial_initialize();
192 	mcf_serial_initialize();
193 	ns9750_serial_initialize();
194 	oc_serial_initialize();
195 	s3c64xx_serial_initialize();
196 	sandbox_serial_initialize();
197 	clps7111_serial_initialize();
198 	imx_serial_initialize();
199 	ixp_serial_initialize();
200 	ks8695_serial_initialize();
201 	lh7a40x_serial_initialize();
202 	max3100_serial_initialize();
203 	mxc_serial_initialize();
204 	netarm_serial_initialize();
205 	pl01x_serial_initialize();
206 	s3c44b0_serial_initialize();
207 	sa1100_serial_initialize();
208 	sh_serial_initialize();
209 
210 	serial_assign(default_serial_console()->name);
211 }
212 
213 /**
214  * serial_stdio_init() - Register serial ports with STDIO core
215  *
216  * This function generates a proxy driver for each serial port driver.
217  * These proxy drivers then register with the STDIO core, making the
218  * serial drivers available as STDIO devices.
219  */
220 void serial_stdio_init(void)
221 {
222 	struct stdio_dev dev;
223 	struct serial_device *s = serial_devices;
224 
225 	while (s) {
226 		memset(&dev, 0, sizeof(dev));
227 
228 		strcpy(dev.name, s->name);
229 		dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT;
230 
231 		dev.start = s->start;
232 		dev.stop = s->stop;
233 		dev.putc = s->putc;
234 		dev.puts = s->puts;
235 		dev.getc = s->getc;
236 		dev.tstc = s->tstc;
237 
238 		stdio_register(&dev);
239 
240 		s = s->next;
241 	}
242 }
243 
244 /**
245  * serial_assign() - Select the serial output device by name
246  * @name:	Name of the serial driver to be used as default output
247  *
248  * This function configures the serial output multiplexing by
249  * selecting which serial device will be used as default. In case
250  * the STDIO "serial" device is selected as stdin/stdout/stderr,
251  * the serial device previously configured by this function will be
252  * used for the particular operation.
253  *
254  * Returns 0 on success, negative on error.
255  */
256 int serial_assign(const char *name)
257 {
258 	struct serial_device *s;
259 
260 	for (s = serial_devices; s; s = s->next) {
261 		if (strcmp(s->name, name))
262 			continue;
263 		serial_current = s;
264 		return 0;
265 	}
266 
267 	return -EINVAL;
268 }
269 
270 /**
271  * serial_reinit_all() - Reinitialize all compiled-in serial ports
272  *
273  * This function reinitializes all serial ports that are compiled
274  * into U-Boot by calling their serial_start() functions.
275  */
276 void serial_reinit_all(void)
277 {
278 	struct serial_device *s;
279 
280 	for (s = serial_devices; s; s = s->next)
281 		s->start();
282 }
283 
284 /**
285  * get_current() - Return pointer to currently selected serial port
286  *
287  * This function returns a pointer to currently selected serial port.
288  * The currently selected serial port is altered by serial_assign()
289  * function.
290  *
291  * In case this function is called before relocation or before any serial
292  * port is configured, this function calls default_serial_console() to
293  * determine the serial port. Otherwise, the configured serial port is
294  * returned.
295  *
296  * Returns pointer to the currently selected serial port on success,
297  * NULL on error.
298  */
299 static struct serial_device *get_current(void)
300 {
301 	struct serial_device *dev;
302 
303 	if (!(gd->flags & GD_FLG_RELOC))
304 		dev = default_serial_console();
305 	else if (!serial_current)
306 		dev = default_serial_console();
307 	else
308 		dev = serial_current;
309 
310 	/* We must have a console device */
311 	if (!dev) {
312 #ifdef CONFIG_SPL_BUILD
313 		puts("Cannot find console\n");
314 		hang();
315 #else
316 		panic("Cannot find console\n");
317 #endif
318 	}
319 
320 	return dev;
321 }
322 
323 /**
324  * serial_init() - Initialize currently selected serial port
325  *
326  * This function initializes the currently selected serial port. This
327  * usually involves setting up the registers of that particular port,
328  * enabling clock and such. This function uses the get_current() call
329  * to determine which port is selected.
330  *
331  * Returns 0 on success, negative on error.
332  */
333 int serial_init(void)
334 {
335 	return get_current()->start();
336 }
337 
338 /**
339  * serial_setbrg() - Configure baud-rate of currently selected serial port
340  *
341  * This function configures the baud-rate of the currently selected
342  * serial port. The baud-rate is retrieved from global data within
343  * the serial port driver. This function uses the get_current() call
344  * to determine which port is selected.
345  *
346  * Returns 0 on success, negative on error.
347  */
348 void serial_setbrg(void)
349 {
350 	get_current()->setbrg();
351 }
352 
353 /**
354  * serial_getc() - Read character from currently selected serial port
355  *
356  * This function retrieves a character from currently selected serial
357  * port. In case there is no character waiting on the serial port,
358  * this function will block and wait for the character to appear. This
359  * function uses the get_current() call to determine which port is
360  * selected.
361  *
362  * Returns the character on success, negative on error.
363  */
364 int serial_getc(void)
365 {
366 	return get_current()->getc();
367 }
368 
369 /**
370  * serial_tstc() - Test if data is available on currently selected serial port
371  *
372  * This function tests if one or more characters are available on
373  * currently selected serial port. This function never blocks. This
374  * function uses the get_current() call to determine which port is
375  * selected.
376  *
377  * Returns positive if character is available, zero otherwise.
378  */
379 int serial_tstc(void)
380 {
381 	return get_current()->tstc();
382 }
383 
384 /**
385  * serial_putc() - Output character via currently selected serial port
386  * @c:	Single character to be output from the serial port.
387  *
388  * This function outputs a character via currently selected serial
389  * port. This character is passed to the serial port driver responsible
390  * for controlling the hardware. The hardware may still be in process
391  * of transmitting another character, therefore this function may block
392  * for a short amount of time. This function uses the get_current()
393  * call to determine which port is selected.
394  */
395 void serial_putc(const char c)
396 {
397 	get_current()->putc(c);
398 }
399 
400 /**
401  * serial_puts() - Output string via currently selected serial port
402  * @s:	Zero-terminated string to be output from the serial port.
403  *
404  * This function outputs a zero-terminated string via currently
405  * selected serial port. This function behaves as an accelerator
406  * in case the hardware can queue multiple characters for transfer.
407  * The whole string that is to be output is available to the function
408  * implementing the hardware manipulation. Transmitting the whole
409  * string may take some time, thus this function may block for some
410  * amount of time. This function uses the get_current() call to
411  * determine which port is selected.
412  */
413 void serial_puts(const char *s)
414 {
415 	get_current()->puts(s);
416 }
417 
418 /**
419  * default_serial_puts() - Output string by calling serial_putc() in loop
420  * @s:	Zero-terminated string to be output from the serial port.
421  *
422  * This function outputs a zero-terminated string by calling serial_putc()
423  * in a loop. Most drivers do not support queueing more than one byte for
424  * transfer, thus this function precisely implements their serial_puts().
425  *
426  * To optimize the number of get_current() calls, this function only
427  * calls get_current() once and then directly accesses the putc() call
428  * of the &struct serial_device .
429  */
430 void default_serial_puts(const char *s)
431 {
432 	struct serial_device *dev = get_current();
433 	while (*s)
434 		dev->putc(*s++);
435 }
436 
437 #if CONFIG_POST & CONFIG_SYS_POST_UART
438 static const int bauds[] = CONFIG_SYS_BAUDRATE_TABLE;
439 
440 /**
441  * uart_post_test() - Test the currently selected serial port using POST
442  * @flags:	POST framework flags
443  *
444  * Do a loopback test of the currently selected serial port. This
445  * function is only useful in the context of the POST testing framwork.
446  * The serial port is firstly configured into loopback mode and then
447  * characters are sent through it.
448  *
449  * Returns 0 on success, value otherwise.
450  */
451 /* Mark weak until post/cpu/.../uart.c migrate over */
452 __weak
453 int uart_post_test(int flags)
454 {
455 	unsigned char c;
456 	int ret, saved_baud, b;
457 	struct serial_device *saved_dev, *s;
458 	bd_t *bd = gd->bd;
459 
460 	/* Save current serial state */
461 	ret = 0;
462 	saved_dev = serial_current;
463 	saved_baud = bd->bi_baudrate;
464 
465 	for (s = serial_devices; s; s = s->next) {
466 		/* If this driver doesn't support loop back, skip it */
467 		if (!s->loop)
468 			continue;
469 
470 		/* Test the next device */
471 		serial_current = s;
472 
473 		ret = serial_init();
474 		if (ret)
475 			goto done;
476 
477 		/* Consume anything that happens to be queued */
478 		while (serial_tstc())
479 			serial_getc();
480 
481 		/* Enable loop back */
482 		s->loop(1);
483 
484 		/* Test every available baud rate */
485 		for (b = 0; b < ARRAY_SIZE(bauds); ++b) {
486 			bd->bi_baudrate = bauds[b];
487 			serial_setbrg();
488 
489 			/*
490 			 * Stick to printable chars to avoid issues:
491 			 *  - terminal corruption
492 			 *  - serial program reacting to sequences and sending
493 			 *    back random extra data
494 			 *  - most serial drivers add in extra chars (like \r\n)
495 			 */
496 			for (c = 0x20; c < 0x7f; ++c) {
497 				/* Send it out */
498 				serial_putc(c);
499 
500 				/* Make sure it's the same one */
501 				ret = (c != serial_getc());
502 				if (ret) {
503 					s->loop(0);
504 					goto done;
505 				}
506 
507 				/* Clean up the output in case it was sent */
508 				serial_putc('\b');
509 				ret = ('\b' != serial_getc());
510 				if (ret) {
511 					s->loop(0);
512 					goto done;
513 				}
514 			}
515 		}
516 
517 		/* Disable loop back */
518 		s->loop(0);
519 
520 		/* XXX: There is no serial_stop() !? */
521 		if (s->stop)
522 			s->stop();
523 	}
524 
525  done:
526 	/* Restore previous serial state */
527 	serial_current = saved_dev;
528 	bd->bi_baudrate = saved_baud;
529 	serial_reinit_all();
530 	serial_setbrg();
531 
532 	return ret;
533 }
534 #endif
535