xref: /openbmc/u-boot/drivers/serial/serial.c (revision ae03661f)
1 /*
2  * (C) Copyright 2000
3  * Rob Taylor, Flying Pig Systems. robt@flyingpig.com.
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 <linux/compiler.h>
26 
27 #include <ns16550.h>
28 #ifdef CONFIG_NS87308
29 #include <ns87308.h>
30 #endif
31 
32 #if defined (CONFIG_SERIAL_MULTI)
33 #include <serial.h>
34 #endif
35 
36 DECLARE_GLOBAL_DATA_PTR;
37 
38 #if !defined(CONFIG_CONS_INDEX)
39 #if defined (CONFIG_SERIAL_MULTI)
40 /*   with CONFIG_SERIAL_MULTI we might have no console
41  *  on these devices
42  */
43 #else
44 #error	"No console index specified."
45 #endif /* CONFIG_SERIAL_MULTI */
46 #elif (CONFIG_CONS_INDEX < 1) || (CONFIG_CONS_INDEX > 4)
47 #error	"Invalid console index value."
48 #endif
49 
50 #if CONFIG_CONS_INDEX == 1 && !defined(CONFIG_SYS_NS16550_COM1)
51 #error	"Console port 1 defined but not configured."
52 #elif CONFIG_CONS_INDEX == 2 && !defined(CONFIG_SYS_NS16550_COM2)
53 #error	"Console port 2 defined but not configured."
54 #elif CONFIG_CONS_INDEX == 3 && !defined(CONFIG_SYS_NS16550_COM3)
55 #error	"Console port 3 defined but not configured."
56 #elif CONFIG_CONS_INDEX == 4 && !defined(CONFIG_SYS_NS16550_COM4)
57 #error	"Console port 4 defined but not configured."
58 #endif
59 
60 /* Note: The port number specified in the functions is 1 based.
61  *	 the array is 0 based.
62  */
63 static NS16550_t serial_ports[4] = {
64 #ifdef CONFIG_SYS_NS16550_COM1
65 	(NS16550_t)CONFIG_SYS_NS16550_COM1,
66 #else
67 	NULL,
68 #endif
69 #ifdef CONFIG_SYS_NS16550_COM2
70 	(NS16550_t)CONFIG_SYS_NS16550_COM2,
71 #else
72 	NULL,
73 #endif
74 #ifdef CONFIG_SYS_NS16550_COM3
75 	(NS16550_t)CONFIG_SYS_NS16550_COM3,
76 #else
77 	NULL,
78 #endif
79 #ifdef CONFIG_SYS_NS16550_COM4
80 	(NS16550_t)CONFIG_SYS_NS16550_COM4
81 #else
82 	NULL
83 #endif
84 };
85 
86 #define PORT	serial_ports[port-1]
87 #if defined(CONFIG_CONS_INDEX)
88 #define CONSOLE	(serial_ports[CONFIG_CONS_INDEX-1])
89 #endif
90 
91 #if defined(CONFIG_SERIAL_MULTI)
92 
93 /* Multi serial device functions */
94 #define DECLARE_ESERIAL_FUNCTIONS(port) \
95     int  eserial##port##_init (void) {\
96 	int clock_divisor; \
97 	clock_divisor = calc_divisor(serial_ports[port-1]); \
98 	NS16550_init(serial_ports[port-1], clock_divisor); \
99 	return(0);}\
100     void eserial##port##_setbrg (void) {\
101 	serial_setbrg_dev(port);}\
102     int  eserial##port##_getc (void) {\
103 	return serial_getc_dev(port);}\
104     int  eserial##port##_tstc (void) {\
105 	return serial_tstc_dev(port);}\
106     void eserial##port##_putc (const char c) {\
107 	serial_putc_dev(port, c);}\
108     void eserial##port##_puts (const char *s) {\
109 	serial_puts_dev(port, s);}
110 
111 /* Serial device descriptor */
112 #define INIT_ESERIAL_STRUCTURE(port, name) {\
113 	name,\
114 	eserial##port##_init,\
115 	NULL,\
116 	eserial##port##_setbrg,\
117 	eserial##port##_getc,\
118 	eserial##port##_tstc,\
119 	eserial##port##_putc,\
120 	eserial##port##_puts, }
121 
122 #endif /* CONFIG_SERIAL_MULTI */
123 
124 static int calc_divisor (NS16550_t port)
125 {
126 #ifdef CONFIG_OMAP1510
127 	/* If can't cleanly clock 115200 set div to 1 */
128 	if ((CONFIG_SYS_NS16550_CLK == 12000000) && (gd->baudrate == 115200)) {
129 		port->osc_12m_sel = OSC_12M_SEL;	/* enable 6.5 * divisor */
130 		return (1);				/* return 1 for base divisor */
131 	}
132 	port->osc_12m_sel = 0;			/* clear if previsouly set */
133 #endif
134 #ifdef CONFIG_OMAP1610
135 	/* If can't cleanly clock 115200 set div to 1 */
136 	if ((CONFIG_SYS_NS16550_CLK == 48000000) && (gd->baudrate == 115200)) {
137 		return (26);		/* return 26 for base divisor */
138 	}
139 #endif
140 
141 #ifdef CONFIG_APTIX
142 #define MODE_X_DIV 13
143 #else
144 #define MODE_X_DIV 16
145 #endif
146 
147 	/* Compute divisor value. Normally, we should simply return:
148 	 *   CONFIG_SYS_NS16550_CLK) / MODE_X_DIV / gd->baudrate
149 	 * but we need to round that value by adding 0.5.
150 	 * Rounding is especially important at high baud rates.
151 	 */
152 	return (CONFIG_SYS_NS16550_CLK + (gd->baudrate * (MODE_X_DIV / 2))) /
153 		(MODE_X_DIV * gd->baudrate);
154 }
155 
156 #if !defined(CONFIG_SERIAL_MULTI)
157 int serial_init (void)
158 {
159 	int clock_divisor;
160 
161 #ifdef CONFIG_NS87308
162 	initialise_ns87308();
163 #endif
164 
165 #ifdef CONFIG_SYS_NS16550_COM1
166 	clock_divisor = calc_divisor(serial_ports[0]);
167 	NS16550_init(serial_ports[0], clock_divisor);
168 #endif
169 #ifdef CONFIG_SYS_NS16550_COM2
170 	clock_divisor = calc_divisor(serial_ports[1]);
171 	NS16550_init(serial_ports[1], clock_divisor);
172 #endif
173 #ifdef CONFIG_SYS_NS16550_COM3
174 	clock_divisor = calc_divisor(serial_ports[2]);
175 	NS16550_init(serial_ports[2], clock_divisor);
176 #endif
177 #ifdef CONFIG_SYS_NS16550_COM4
178 	clock_divisor = calc_divisor(serial_ports[3]);
179 	NS16550_init(serial_ports[3], clock_divisor);
180 #endif
181 
182 	return (0);
183 }
184 #endif
185 
186 void
187 _serial_putc(const char c,const int port)
188 {
189 	if (c == '\n')
190 		NS16550_putc(PORT, '\r');
191 
192 	NS16550_putc(PORT, c);
193 }
194 
195 void
196 _serial_putc_raw(const char c,const int port)
197 {
198 	NS16550_putc(PORT, c);
199 }
200 
201 void
202 _serial_puts (const char *s,const int port)
203 {
204 	while (*s) {
205 		_serial_putc (*s++,port);
206 	}
207 }
208 
209 
210 int
211 _serial_getc(const int port)
212 {
213 	return NS16550_getc(PORT);
214 }
215 
216 int
217 _serial_tstc(const int port)
218 {
219 	return NS16550_tstc(PORT);
220 }
221 
222 void
223 _serial_setbrg (const int port)
224 {
225 	int clock_divisor;
226 
227 	clock_divisor = calc_divisor(PORT);
228 	NS16550_reinit(PORT, clock_divisor);
229 }
230 
231 #if defined(CONFIG_SERIAL_MULTI)
232 static inline void
233 serial_putc_dev(unsigned int dev_index,const char c)
234 {
235 	_serial_putc(c,dev_index);
236 }
237 #else
238 void
239 serial_putc(const char c)
240 {
241 	_serial_putc(c,CONFIG_CONS_INDEX);
242 }
243 #endif
244 
245 #if defined(CONFIG_SERIAL_MULTI)
246 static inline void
247 serial_putc_raw_dev(unsigned int dev_index,const char c)
248 {
249 	_serial_putc_raw(c,dev_index);
250 }
251 #else
252 void
253 serial_putc_raw(const char c)
254 {
255 	_serial_putc_raw(c,CONFIG_CONS_INDEX);
256 }
257 #endif
258 
259 #if defined(CONFIG_SERIAL_MULTI)
260 static inline void
261 serial_puts_dev(unsigned int dev_index,const char *s)
262 {
263 	_serial_puts(s,dev_index);
264 }
265 #else
266 void
267 serial_puts(const char *s)
268 {
269 	_serial_puts(s,CONFIG_CONS_INDEX);
270 }
271 #endif
272 
273 #if defined(CONFIG_SERIAL_MULTI)
274 static inline int
275 serial_getc_dev(unsigned int dev_index)
276 {
277 	return _serial_getc(dev_index);
278 }
279 #else
280 int
281 serial_getc(void)
282 {
283 	return _serial_getc(CONFIG_CONS_INDEX);
284 }
285 #endif
286 
287 #if defined(CONFIG_SERIAL_MULTI)
288 static inline int
289 serial_tstc_dev(unsigned int dev_index)
290 {
291 	return _serial_tstc(dev_index);
292 }
293 #else
294 int
295 serial_tstc(void)
296 {
297 	return _serial_tstc(CONFIG_CONS_INDEX);
298 }
299 #endif
300 
301 #if defined(CONFIG_SERIAL_MULTI)
302 static inline void
303 serial_setbrg_dev(unsigned int dev_index)
304 {
305 	_serial_setbrg(dev_index);
306 }
307 #else
308 void
309 serial_setbrg(void)
310 {
311 	_serial_setbrg(CONFIG_CONS_INDEX);
312 }
313 #endif
314 
315 #if defined(CONFIG_SERIAL_MULTI)
316 
317 DECLARE_ESERIAL_FUNCTIONS(1);
318 struct serial_device eserial1_device =
319 	INIT_ESERIAL_STRUCTURE(1, "eserial0");
320 DECLARE_ESERIAL_FUNCTIONS(2);
321 struct serial_device eserial2_device =
322 	INIT_ESERIAL_STRUCTURE(2, "eserial1");
323 DECLARE_ESERIAL_FUNCTIONS(3);
324 struct serial_device eserial3_device =
325 	INIT_ESERIAL_STRUCTURE(3, "eserial2");
326 DECLARE_ESERIAL_FUNCTIONS(4);
327 struct serial_device eserial4_device =
328 	INIT_ESERIAL_STRUCTURE(4, "eserial3");
329 
330 __weak struct serial_device *default_serial_console(void)
331 {
332 #if CONFIG_CONS_INDEX == 1
333 	return &eserial1_device;
334 #elif CONFIG_CONS_INDEX == 2
335 	return &eserial2_device;
336 #elif CONFIG_CONS_INDEX == 3
337 	return &eserial3_device;
338 #elif CONFIG_CONS_INDEX == 4
339 	return &eserial4_device;
340 #else
341 #error "Bad CONFIG_CONS_INDEX."
342 #endif
343 }
344 
345 #endif /* CONFIG_SERIAL_MULTI */
346