xref: /openbmc/u-boot/drivers/serial/serial.c (revision c6af2e7d)
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 
88 #if defined(CONFIG_SERIAL_MULTI)
89 
90 /* Multi serial device functions */
91 #define DECLARE_ESERIAL_FUNCTIONS(port) \
92     int  eserial##port##_init (void) {\
93 	int clock_divisor; \
94 	clock_divisor = calc_divisor(serial_ports[port-1]); \
95 	NS16550_init(serial_ports[port-1], clock_divisor); \
96 	return(0);}\
97     void eserial##port##_setbrg (void) {\
98 	serial_setbrg_dev(port);}\
99     int  eserial##port##_getc (void) {\
100 	return serial_getc_dev(port);}\
101     int  eserial##port##_tstc (void) {\
102 	return serial_tstc_dev(port);}\
103     void eserial##port##_putc (const char c) {\
104 	serial_putc_dev(port, c);}\
105     void eserial##port##_puts (const char *s) {\
106 	serial_puts_dev(port, s);}
107 
108 /* Serial device descriptor */
109 #define INIT_ESERIAL_STRUCTURE(port, name) {\
110 	name,\
111 	eserial##port##_init,\
112 	NULL,\
113 	eserial##port##_setbrg,\
114 	eserial##port##_getc,\
115 	eserial##port##_tstc,\
116 	eserial##port##_putc,\
117 	eserial##port##_puts, }
118 
119 #endif /* CONFIG_SERIAL_MULTI */
120 
121 static int calc_divisor (NS16550_t port)
122 {
123 #ifdef CONFIG_OMAP1510
124 	/* If can't cleanly clock 115200 set div to 1 */
125 	if ((CONFIG_SYS_NS16550_CLK == 12000000) && (gd->baudrate == 115200)) {
126 		port->osc_12m_sel = OSC_12M_SEL;	/* enable 6.5 * divisor */
127 		return (1);				/* return 1 for base divisor */
128 	}
129 	port->osc_12m_sel = 0;			/* clear if previsouly set */
130 #endif
131 #ifdef CONFIG_OMAP1610
132 	/* If can't cleanly clock 115200 set div to 1 */
133 	if ((CONFIG_SYS_NS16550_CLK == 48000000) && (gd->baudrate == 115200)) {
134 		return (26);		/* return 26 for base divisor */
135 	}
136 #endif
137 
138 #ifdef CONFIG_APTIX
139 #define MODE_X_DIV 13
140 #else
141 #define MODE_X_DIV 16
142 #endif
143 
144 	/* Compute divisor value. Normally, we should simply return:
145 	 *   CONFIG_SYS_NS16550_CLK) / MODE_X_DIV / gd->baudrate
146 	 * but we need to round that value by adding 0.5.
147 	 * Rounding is especially important at high baud rates.
148 	 */
149 	return (CONFIG_SYS_NS16550_CLK + (gd->baudrate * (MODE_X_DIV / 2))) /
150 		(MODE_X_DIV * gd->baudrate);
151 }
152 
153 #if !defined(CONFIG_SERIAL_MULTI)
154 int serial_init (void)
155 {
156 	int clock_divisor;
157 
158 #ifdef CONFIG_NS87308
159 	initialise_ns87308();
160 #endif
161 
162 #ifdef CONFIG_SYS_NS16550_COM1
163 	clock_divisor = calc_divisor(serial_ports[0]);
164 	NS16550_init(serial_ports[0], clock_divisor);
165 #endif
166 #ifdef CONFIG_SYS_NS16550_COM2
167 	clock_divisor = calc_divisor(serial_ports[1]);
168 	NS16550_init(serial_ports[1], clock_divisor);
169 #endif
170 #ifdef CONFIG_SYS_NS16550_COM3
171 	clock_divisor = calc_divisor(serial_ports[2]);
172 	NS16550_init(serial_ports[2], clock_divisor);
173 #endif
174 #ifdef CONFIG_SYS_NS16550_COM4
175 	clock_divisor = calc_divisor(serial_ports[3]);
176 	NS16550_init(serial_ports[3], clock_divisor);
177 #endif
178 
179 	return (0);
180 }
181 #endif
182 
183 void
184 _serial_putc(const char c,const int port)
185 {
186 	if (c == '\n')
187 		NS16550_putc(PORT, '\r');
188 
189 	NS16550_putc(PORT, c);
190 }
191 
192 void
193 _serial_putc_raw(const char c,const int port)
194 {
195 	NS16550_putc(PORT, c);
196 }
197 
198 void
199 _serial_puts (const char *s,const int port)
200 {
201 	while (*s) {
202 		_serial_putc (*s++,port);
203 	}
204 }
205 
206 
207 int
208 _serial_getc(const int port)
209 {
210 	return NS16550_getc(PORT);
211 }
212 
213 int
214 _serial_tstc(const int port)
215 {
216 	return NS16550_tstc(PORT);
217 }
218 
219 void
220 _serial_setbrg (const int port)
221 {
222 	int clock_divisor;
223 
224 	clock_divisor = calc_divisor(PORT);
225 	NS16550_reinit(PORT, clock_divisor);
226 }
227 
228 #if defined(CONFIG_SERIAL_MULTI)
229 static inline void
230 serial_putc_dev(unsigned int dev_index,const char c)
231 {
232 	_serial_putc(c,dev_index);
233 }
234 #else
235 void
236 serial_putc(const char c)
237 {
238 	_serial_putc(c,CONFIG_CONS_INDEX);
239 }
240 #endif
241 
242 #if defined(CONFIG_SERIAL_MULTI)
243 static inline void
244 serial_putc_raw_dev(unsigned int dev_index,const char c)
245 {
246 	_serial_putc_raw(c,dev_index);
247 }
248 #else
249 void
250 serial_putc_raw(const char c)
251 {
252 	_serial_putc_raw(c,CONFIG_CONS_INDEX);
253 }
254 #endif
255 
256 #if defined(CONFIG_SERIAL_MULTI)
257 static inline void
258 serial_puts_dev(unsigned int dev_index,const char *s)
259 {
260 	_serial_puts(s,dev_index);
261 }
262 #else
263 void
264 serial_puts(const char *s)
265 {
266 	_serial_puts(s,CONFIG_CONS_INDEX);
267 }
268 #endif
269 
270 #if defined(CONFIG_SERIAL_MULTI)
271 static inline int
272 serial_getc_dev(unsigned int dev_index)
273 {
274 	return _serial_getc(dev_index);
275 }
276 #else
277 int
278 serial_getc(void)
279 {
280 	return _serial_getc(CONFIG_CONS_INDEX);
281 }
282 #endif
283 
284 #if defined(CONFIG_SERIAL_MULTI)
285 static inline int
286 serial_tstc_dev(unsigned int dev_index)
287 {
288 	return _serial_tstc(dev_index);
289 }
290 #else
291 int
292 serial_tstc(void)
293 {
294 	return _serial_tstc(CONFIG_CONS_INDEX);
295 }
296 #endif
297 
298 #if defined(CONFIG_SERIAL_MULTI)
299 static inline void
300 serial_setbrg_dev(unsigned int dev_index)
301 {
302 	_serial_setbrg(dev_index);
303 }
304 #else
305 void
306 serial_setbrg(void)
307 {
308 	_serial_setbrg(CONFIG_CONS_INDEX);
309 }
310 #endif
311 
312 #if defined(CONFIG_SERIAL_MULTI)
313 
314 DECLARE_ESERIAL_FUNCTIONS(1);
315 struct serial_device eserial1_device =
316 	INIT_ESERIAL_STRUCTURE(1, "eserial0");
317 DECLARE_ESERIAL_FUNCTIONS(2);
318 struct serial_device eserial2_device =
319 	INIT_ESERIAL_STRUCTURE(2, "eserial1");
320 DECLARE_ESERIAL_FUNCTIONS(3);
321 struct serial_device eserial3_device =
322 	INIT_ESERIAL_STRUCTURE(3, "eserial2");
323 DECLARE_ESERIAL_FUNCTIONS(4);
324 struct serial_device eserial4_device =
325 	INIT_ESERIAL_STRUCTURE(4, "eserial3");
326 
327 __weak struct serial_device *default_serial_console(void)
328 {
329 #if CONFIG_CONS_INDEX == 1
330 	return &eserial1_device;
331 #elif CONFIG_CONS_INDEX == 2
332 	return &eserial2_device;
333 #elif CONFIG_CONS_INDEX == 3
334 	return &eserial3_device;
335 #elif CONFIG_CONS_INDEX == 4
336 	return &eserial4_device;
337 #else
338 #error "Bad CONFIG_CONS_INDEX."
339 #endif
340 }
341 
342 #endif /* CONFIG_SERIAL_MULTI */
343