xref: /freebsd/stand/i386/libi386/comconsole.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 /*-
2  * Copyright (c) 1998 Michael Smith (msmith@freebsd.org)
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <stand.h>
27 #include <bootstrap.h>
28 #include <machine/cpufunc.h>
29 #include <dev/ic/ns16550.h>
30 #include <dev/pci/pcireg.h>
31 #include "libi386.h"
32 
33 #define COMC_FMT	0x3		/* 8N1 */
34 #define COMC_TXWAIT	0x40000		/* transmit timeout */
35 #define COMC_BPS(x)	(115200 / (x))	/* speed to DLAB divisor */
36 #define COMC_DIV2BPS(x)	(115200 / (x))	/* DLAB divisor to speed */
37 
38 #ifndef	COMPORT
39 #define COMPORT		0x3f8
40 #endif
41 #ifndef	COMSPEED
42 #define COMSPEED	115200
43 #endif
44 
45 static void	comc_probe(struct console *cp);
46 static int	comc_init(int arg);
47 static void	comc_putchar(int c);
48 static int	comc_getchar(void);
49 static int	comc_getspeed(void);
50 static int	comc_ischar(void);
51 static int	comc_parseint(const char *string);
52 static uint32_t comc_parse_pcidev(const char *string);
53 static int	comc_pcidev_set(struct env_var *ev, int flags,
54 		    const void *value);
55 static int	comc_pcidev_handle(uint32_t locator);
56 static int	comc_port_set(struct env_var *ev, int flags,
57 		    const void *value);
58 static void	comc_setup(int speed, int port);
59 static int	comc_speed_set(struct env_var *ev, int flags,
60 		    const void *value);
61 
62 static int	comc_curspeed;
63 static int	comc_port = COMPORT;
64 static uint32_t	comc_locator;
65 
66 struct console comconsole = {
67 	.c_name = "comconsole",
68 	.c_desc = "serial port",
69 	.c_flags = 0,
70 	.c_probe = comc_probe,
71 	.c_init = comc_init,
72 	.c_out = comc_putchar,
73 	.c_in = comc_getchar,
74 	.c_ready = comc_ischar
75 };
76 
77 static void
78 comc_probe(struct console *cp)
79 {
80 	char intbuf[16];
81 	char *cons, *env;
82 	int speed, port;
83 	uint32_t locator;
84 
85 	if (comc_curspeed == 0) {
86 		comc_curspeed = COMSPEED;
87 		/*
88 		 * Assume that the speed was set by an earlier boot loader if
89 		 * comconsole is already the preferred console.
90 		 */
91 		cons = getenv("console");
92 		if ((cons != NULL && strcmp(cons, comconsole.c_name) == 0) ||
93 		    getenv("boot_multicons") != NULL) {
94 			comc_curspeed = comc_getspeed();
95 		}
96 
97 		env = getenv("comconsole_speed");
98 		if (env != NULL) {
99 			speed = comc_parseint(env);
100 			if (speed > 0)
101 				comc_curspeed = speed;
102 		}
103 
104 		sprintf(intbuf, "%d", comc_curspeed);
105 		unsetenv("comconsole_speed");
106 		env_setenv("comconsole_speed", EV_VOLATILE, intbuf,
107 		    comc_speed_set, env_nounset);
108 
109 		env = getenv("comconsole_port");
110 		if (env != NULL) {
111 			port = comc_parseint(env);
112 			if (port > 0)
113 				comc_port = port;
114 		}
115 
116 		sprintf(intbuf, "%d", comc_port);
117 		unsetenv("comconsole_port");
118 		env_setenv("comconsole_port", EV_VOLATILE, intbuf,
119 		    comc_port_set, env_nounset);
120 
121 		env = getenv("comconsole_pcidev");
122 		if (env != NULL) {
123 			locator = comc_parse_pcidev(env);
124 			if (locator != 0)
125 				comc_pcidev_handle(locator);
126 		}
127 
128 		unsetenv("comconsole_pcidev");
129 		env_setenv("comconsole_pcidev", EV_VOLATILE, env,
130 		    comc_pcidev_set, env_nounset);
131 	}
132 	comc_setup(comc_curspeed, comc_port);
133 }
134 
135 static int
136 comc_init(int arg)
137 {
138 
139 	comc_setup(comc_curspeed, comc_port);
140 
141 	if ((comconsole.c_flags & (C_PRESENTIN | C_PRESENTOUT)) ==
142 	    (C_PRESENTIN | C_PRESENTOUT))
143 		return (CMD_OK);
144 	return (CMD_ERROR);
145 }
146 
147 static void
148 comc_putchar(int c)
149 {
150 	int wait;
151 
152 	for (wait = COMC_TXWAIT; wait > 0; wait--)
153 		if (inb(comc_port + com_lsr) & LSR_TXRDY) {
154 			outb(comc_port + com_data, (u_char)c);
155 			break;
156 		}
157 }
158 
159 static int
160 comc_getchar(void)
161 {
162 	return (comc_ischar() ? inb(comc_port + com_data) : -1);
163 }
164 
165 static int
166 comc_ischar(void)
167 {
168 	return (inb(comc_port + com_lsr) & LSR_RXRDY);
169 }
170 
171 static int
172 comc_speed_set(struct env_var *ev, int flags, const void *value)
173 {
174 	int speed;
175 
176 	if (value == NULL || (speed = comc_parseint(value)) <= 0) {
177 		printf("Invalid speed\n");
178 		return (CMD_ERROR);
179 	}
180 
181 	if (comc_curspeed != speed)
182 		comc_setup(speed, comc_port);
183 
184 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
185 
186 	return (CMD_OK);
187 }
188 
189 static int
190 comc_port_set(struct env_var *ev, int flags, const void *value)
191 {
192 	int port;
193 
194 	if (value == NULL || (port = comc_parseint(value)) <= 0) {
195 		printf("Invalid port\n");
196 		return (CMD_ERROR);
197 	}
198 
199 	if (comc_port != port)
200 		comc_setup(comc_curspeed, port);
201 
202 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
203 
204 	return (CMD_OK);
205 }
206 
207 /*
208  * Input: bus:dev:func[:bar]. If bar is not specified, it is 0x10.
209  * Output: bar[24:16] bus[15:8] dev[7:3] func[2:0]
210  */
211 static uint32_t
212 comc_parse_pcidev(const char *string)
213 {
214 #ifdef EFI
215 	/* We don't support PCI in EFI yet */
216 	return (0);
217 #else
218 	char *p, *p1;
219 	uint8_t bus, dev, func, bar;
220 	uint32_t locator;
221 	int pres;
222 
223 	pres = strtol(string, &p, 0);
224 	if (p == string || *p != ':' || pres < 0 )
225 		return (0);
226 	bus = pres;
227 	p1 = ++p;
228 
229 	pres = strtol(p1, &p, 0);
230 	if (p == string || *p != ':' || pres < 0 )
231 		return (0);
232 	dev = pres;
233 	p1 = ++p;
234 
235 	pres = strtol(p1, &p, 0);
236 	if (p == string || (*p != ':' && *p != '\0') || pres < 0 )
237 		return (0);
238 	func = pres;
239 
240 	if (*p == ':') {
241 		p1 = ++p;
242 		pres = strtol(p1, &p, 0);
243 		if (p == string || *p != '\0' || pres <= 0 )
244 			return (0);
245 		bar = pres;
246 	} else
247 		bar = 0x10;
248 
249 	locator = (bar << 16) | biospci_locator(bus, dev, func);
250 	return (locator);
251 #endif
252 }
253 
254 static int
255 comc_pcidev_handle(uint32_t locator)
256 {
257 #ifdef EFI
258 	/* We don't support PCI in EFI yet */
259 	return (CMD_ERROR);
260 #else
261 	char intbuf[64];
262 	uint32_t port;
263 
264 	if (biospci_read_config(locator & 0xffff,
265 	    (locator & 0xff0000) >> 16, BIOSPCI_32BITS, &port) == -1) {
266 		printf("Cannot read bar at 0x%x\n", locator);
267 		return (CMD_ERROR);
268 	}
269 
270 	/*
271 	 * biospci_read_config() sets port == 0xffffffff if the pcidev
272 	 * isn't found on the bus.  Check for 0xffffffff and return to not
273 	 * panic in BTX.
274 	 */
275 	if (port == 0xffffffff) {
276 		printf("Cannot find specified pcidev\n");
277 		return (CMD_ERROR);
278 	}
279 	if (!PCI_BAR_IO(port)) {
280 		printf("Memory bar at 0x%x\n", locator);
281 		return (CMD_ERROR);
282 	}
283         port &= PCIM_BAR_IO_BASE;
284 
285 	sprintf(intbuf, "%d", port);
286 	unsetenv("comconsole_port");
287 	env_setenv("comconsole_port", EV_VOLATILE, intbuf,
288 		   comc_port_set, env_nounset);
289 
290 	comc_setup(comc_curspeed, port);
291 	comc_locator = locator;
292 
293 	return (CMD_OK);
294 #endif
295 }
296 
297 static int
298 comc_pcidev_set(struct env_var *ev, int flags, const void *value)
299 {
300 	uint32_t locator;
301 	int error;
302 
303 	if (value == NULL || (locator = comc_parse_pcidev(value)) <= 0) {
304 		printf("Invalid pcidev\n");
305 		return (CMD_ERROR);
306 	}
307 	if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) != 0 &&
308 	    comc_locator != locator) {
309 		error = comc_pcidev_handle(locator);
310 		if (error != CMD_OK)
311 			return (error);
312 	}
313 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
314 	return (CMD_OK);
315 }
316 
317 static void
318 comc_setup(int speed, int port)
319 {
320 	static int TRY_COUNT = 1000000;
321 	char intbuf[64];
322 	int tries;
323 
324 	comc_curspeed = speed;
325 	comc_port = port;
326 	if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) == 0)
327 		return;
328 
329 	unsetenv("hw.uart.console");
330 
331 #define	COMC_TEST	0xbb
332 	/*
333 	 * Write byte to scratch register and read it out.
334 	 */
335 	outb(comc_port + com_scr, COMC_TEST);
336 	if (inb(comc_port + com_scr) != COMC_TEST) {
337 		comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
338 		return;
339 	}
340 
341 	outb(comc_port + com_cfcr, CFCR_DLAB | COMC_FMT);
342 	outb(comc_port + com_dlbl, COMC_BPS(speed) & 0xff);
343 	outb(comc_port + com_dlbh, COMC_BPS(speed) >> 8);
344 	outb(comc_port + com_cfcr, COMC_FMT);
345 	outb(comc_port + com_mcr, MCR_RTS | MCR_DTR);
346 
347 	tries = 0;
348 	do
349 		inb(comc_port + com_data);
350 	while (inb(comc_port + com_lsr) & LSR_RXRDY && ++tries < TRY_COUNT);
351 
352 	if (tries < TRY_COUNT) {
353 		comconsole.c_flags |= (C_PRESENTIN | C_PRESENTOUT);
354 		sprintf(intbuf, "io:%d,br:%d", comc_port, comc_curspeed);
355 		env_setenv("hw.uart.console", EV_VOLATILE, intbuf, NULL, NULL);
356 	} else
357 		comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
358 }
359 
360 static int
361 comc_parseint(const char *speedstr)
362 {
363 	char *p;
364 	int speed;
365 
366 	speed = strtol(speedstr, &p, 0);
367 	if (p == speedstr || *p != '\0' || speed <= 0)
368 		return (-1);
369 
370 	return (speed);
371 }
372 
373 static int
374 comc_getspeed(void)
375 {
376 	u_int	divisor;
377 	u_char	dlbh;
378 	u_char	dlbl;
379 	u_char	cfcr;
380 
381 	cfcr = inb(comc_port + com_cfcr);
382 	outb(comc_port + com_cfcr, CFCR_DLAB | cfcr);
383 
384 	dlbl = inb(comc_port + com_dlbl);
385 	dlbh = inb(comc_port + com_dlbh);
386 
387 	outb(comc_port + com_cfcr, cfcr);
388 
389 	divisor = dlbh << 8 | dlbl;
390 
391 	/* XXX there should be more sanity checking. */
392 	if (divisor == 0)
393 		return (COMSPEED);
394 	return (COMC_DIV2BPS(divisor));
395 }
396