xref: /freebsd/stand/i386/libi386/comconsole.c (revision ce6a89e27cd190313be39bb479880aeda4778436)
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 <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <stand.h>
30 #include <bootstrap.h>
31 #include <machine/cpufunc.h>
32 #include <dev/ic/ns16550.h>
33 #include <dev/pci/pcireg.h>
34 #include "libi386.h"
35 
36 #define COMC_FMT	0x3		/* 8N1 */
37 #define COMC_TXWAIT	0x40000		/* transmit timeout */
38 #define COMC_BPS(x)	(115200 / (x))	/* speed to DLAB divisor */
39 #define COMC_DIV2BPS(x)	(115200 / (x))	/* DLAB divisor to speed */
40 
41 #ifndef	COMPORT
42 #define COMPORT		0x3f8
43 #endif
44 #ifndef	COMSPEED
45 #define COMSPEED	9600
46 #endif
47 
48 static void	comc_probe(struct console *cp);
49 static int	comc_init(int arg);
50 static void	comc_putchar(int c);
51 static int	comc_getchar(void);
52 static int	comc_getspeed(void);
53 static int	comc_ischar(void);
54 static int	comc_parseint(const char *string);
55 static uint32_t comc_parse_pcidev(const char *string);
56 static int	comc_pcidev_set(struct env_var *ev, int flags,
57 		    const void *value);
58 static int	comc_pcidev_handle(uint32_t locator);
59 static int	comc_port_set(struct env_var *ev, int flags,
60 		    const void *value);
61 static void	comc_setup(int speed, int port);
62 static int	comc_speed_set(struct env_var *ev, int flags,
63 		    const void *value);
64 
65 static int	comc_curspeed;
66 static int	comc_port = COMPORT;
67 static uint32_t	comc_locator;
68 
69 struct console comconsole = {
70 	.c_name = "comconsole",
71 	.c_desc = "serial port",
72 	.c_flags = 0,
73 	.c_probe = comc_probe,
74 	.c_init = comc_init,
75 	.c_out = comc_putchar,
76 	.c_in = comc_getchar,
77 	.c_ready = comc_ischar
78 };
79 
80 static void
81 comc_probe(struct console *cp)
82 {
83 	char intbuf[16];
84 	char *cons, *env;
85 	int speed, port;
86 	uint32_t locator;
87 
88 	if (comc_curspeed == 0) {
89 		comc_curspeed = COMSPEED;
90 		/*
91 		 * Assume that the speed was set by an earlier boot loader if
92 		 * comconsole is already the preferred console.
93 		 */
94 		cons = getenv("console");
95 		if ((cons != NULL && strcmp(cons, comconsole.c_name) == 0) ||
96 		    getenv("boot_multicons") != NULL) {
97 			comc_curspeed = comc_getspeed();
98 		}
99 
100 		env = getenv("comconsole_speed");
101 		if (env != NULL) {
102 			speed = comc_parseint(env);
103 			if (speed > 0)
104 				comc_curspeed = speed;
105 		}
106 
107 		sprintf(intbuf, "%d", comc_curspeed);
108 		unsetenv("comconsole_speed");
109 		env_setenv("comconsole_speed", EV_VOLATILE, intbuf,
110 		    comc_speed_set, env_nounset);
111 
112 		env = getenv("comconsole_port");
113 		if (env != NULL) {
114 			port = comc_parseint(env);
115 			if (port > 0)
116 				comc_port = port;
117 		}
118 
119 		sprintf(intbuf, "%d", comc_port);
120 		unsetenv("comconsole_port");
121 		env_setenv("comconsole_port", EV_VOLATILE, intbuf,
122 		    comc_port_set, env_nounset);
123 
124 		env = getenv("comconsole_pcidev");
125 		if (env != NULL) {
126 			locator = comc_parse_pcidev(env);
127 			if (locator != 0)
128 				comc_pcidev_handle(locator);
129 		}
130 
131 		unsetenv("comconsole_pcidev");
132 		env_setenv("comconsole_pcidev", EV_VOLATILE, env,
133 		    comc_pcidev_set, env_nounset);
134 	}
135 	comc_setup(comc_curspeed, comc_port);
136 }
137 
138 static int
139 comc_init(int arg)
140 {
141 
142 	comc_setup(comc_curspeed, comc_port);
143 
144 	if ((comconsole.c_flags & (C_PRESENTIN | C_PRESENTOUT)) ==
145 	    (C_PRESENTIN | C_PRESENTOUT))
146 		return (CMD_OK);
147 	return (CMD_ERROR);
148 }
149 
150 static void
151 comc_putchar(int c)
152 {
153 	int wait;
154 
155 	for (wait = COMC_TXWAIT; wait > 0; wait--)
156 		if (inb(comc_port + com_lsr) & LSR_TXRDY) {
157 			outb(comc_port + com_data, (u_char)c);
158 			break;
159 		}
160 }
161 
162 static int
163 comc_getchar(void)
164 {
165 	return (comc_ischar() ? inb(comc_port + com_data) : -1);
166 }
167 
168 static int
169 comc_ischar(void)
170 {
171 	return (inb(comc_port + com_lsr) & LSR_RXRDY);
172 }
173 
174 static int
175 comc_speed_set(struct env_var *ev, int flags, const void *value)
176 {
177 	int speed;
178 
179 	if (value == NULL || (speed = comc_parseint(value)) <= 0) {
180 		printf("Invalid speed\n");
181 		return (CMD_ERROR);
182 	}
183 
184 	if (comc_curspeed != speed)
185 		comc_setup(speed, comc_port);
186 
187 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
188 
189 	return (CMD_OK);
190 }
191 
192 static int
193 comc_port_set(struct env_var *ev, int flags, const void *value)
194 {
195 	int port;
196 
197 	if (value == NULL || (port = comc_parseint(value)) <= 0) {
198 		printf("Invalid port\n");
199 		return (CMD_ERROR);
200 	}
201 
202 	if (comc_port != port)
203 		comc_setup(comc_curspeed, port);
204 
205 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
206 
207 	return (CMD_OK);
208 }
209 
210 /*
211  * Input: bus:dev:func[:bar]. If bar is not specified, it is 0x10.
212  * Output: bar[24:16] bus[15:8] dev[7:3] func[2:0]
213  */
214 static uint32_t
215 comc_parse_pcidev(const char *string)
216 {
217 #ifdef EFI
218 	/* We don't support PCI in EFI yet */
219 	return (0);
220 #else
221 	char *p, *p1;
222 	uint8_t bus, dev, func, bar;
223 	uint32_t locator;
224 	int pres;
225 
226 	pres = strtol(string, &p, 0);
227 	if (p == string || *p != ':' || pres < 0 )
228 		return (0);
229 	bus = pres;
230 	p1 = ++p;
231 
232 	pres = strtol(p1, &p, 0);
233 	if (p == string || *p != ':' || pres < 0 )
234 		return (0);
235 	dev = pres;
236 	p1 = ++p;
237 
238 	pres = strtol(p1, &p, 0);
239 	if (p == string || (*p != ':' && *p != '\0') || pres < 0 )
240 		return (0);
241 	func = pres;
242 
243 	if (*p == ':') {
244 		p1 = ++p;
245 		pres = strtol(p1, &p, 0);
246 		if (p == string || *p != '\0' || pres <= 0 )
247 			return (0);
248 		bar = pres;
249 	} else
250 		bar = 0x10;
251 
252 	locator = (bar << 16) | biospci_locator(bus, dev, func);
253 	return (locator);
254 #endif
255 }
256 
257 static int
258 comc_pcidev_handle(uint32_t locator)
259 {
260 #ifdef EFI
261 	/* We don't support PCI in EFI yet */
262 	return (CMD_ERROR);
263 #else
264 	char intbuf[64];
265 	uint32_t port;
266 
267 	if (biospci_read_config(locator & 0xffff,
268 	    (locator & 0xff0000) >> 16, BIOSPCI_32BITS, &port) == -1) {
269 		printf("Cannot read bar at 0x%x\n", locator);
270 		return (CMD_ERROR);
271 	}
272 
273 	/*
274 	 * biospci_read_config() sets port == 0xffffffff if the pcidev
275 	 * isn't found on the bus.  Check for 0xffffffff and return to not
276 	 * panic in BTX.
277 	 */
278 	if (port == 0xffffffff) {
279 		printf("Cannot find specified pcidev\n");
280 		return (CMD_ERROR);
281 	}
282 	if (!PCI_BAR_IO(port)) {
283 		printf("Memory bar at 0x%x\n", locator);
284 		return (CMD_ERROR);
285 	}
286         port &= PCIM_BAR_IO_BASE;
287 
288 	sprintf(intbuf, "%d", port);
289 	unsetenv("comconsole_port");
290 	env_setenv("comconsole_port", EV_VOLATILE, intbuf,
291 		   comc_port_set, env_nounset);
292 
293 	comc_setup(comc_curspeed, port);
294 	comc_locator = locator;
295 
296 	return (CMD_OK);
297 #endif
298 }
299 
300 static int
301 comc_pcidev_set(struct env_var *ev, int flags, const void *value)
302 {
303 	uint32_t locator;
304 	int error;
305 
306 	if (value == NULL || (locator = comc_parse_pcidev(value)) <= 0) {
307 		printf("Invalid pcidev\n");
308 		return (CMD_ERROR);
309 	}
310 	if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) != 0 &&
311 	    comc_locator != locator) {
312 		error = comc_pcidev_handle(locator);
313 		if (error != CMD_OK)
314 			return (error);
315 	}
316 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
317 	return (CMD_OK);
318 }
319 
320 static void
321 comc_setup(int speed, int port)
322 {
323 	static int TRY_COUNT = 1000000;
324 	char intbuf[64];
325 	int tries;
326 
327 	unsetenv("hw.uart.console");
328 	comc_curspeed = speed;
329 	comc_port = port;
330 	if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) == 0)
331 		return;
332 
333 #define	COMC_TEST	0xbb
334 	/*
335 	 * Write byte to scratch register and read it out.
336 	 */
337 	outb(comc_port + com_scr, COMC_TEST);
338 	if (inb(comc_port + com_scr) != COMC_TEST) {
339 		comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
340 		return;
341 	}
342 
343 	outb(comc_port + com_cfcr, CFCR_DLAB | COMC_FMT);
344 	outb(comc_port + com_dlbl, COMC_BPS(speed) & 0xff);
345 	outb(comc_port + com_dlbh, COMC_BPS(speed) >> 8);
346 	outb(comc_port + com_cfcr, COMC_FMT);
347 	outb(comc_port + com_mcr, MCR_RTS | MCR_DTR);
348 
349 	tries = 0;
350 	do
351 		inb(comc_port + com_data);
352 	while (inb(comc_port + com_lsr) & LSR_RXRDY && ++tries < TRY_COUNT);
353 
354 	if (tries < TRY_COUNT) {
355 		comconsole.c_flags |= (C_PRESENTIN | C_PRESENTOUT);
356 		sprintf(intbuf, "io:%d,br:%d", comc_port, comc_curspeed);
357 		env_setenv("hw.uart.console", EV_VOLATILE, intbuf, NULL, NULL);
358 	} else
359 		comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
360 }
361 
362 static int
363 comc_parseint(const char *speedstr)
364 {
365 	char *p;
366 	int speed;
367 
368 	speed = strtol(speedstr, &p, 0);
369 	if (p == speedstr || *p != '\0' || speed <= 0)
370 		return (-1);
371 
372 	return (speed);
373 }
374 
375 static int
376 comc_getspeed(void)
377 {
378 	u_int	divisor;
379 	u_char	dlbh;
380 	u_char	dlbl;
381 	u_char	cfcr;
382 
383 	cfcr = inb(comc_port + com_cfcr);
384 	outb(comc_port + com_cfcr, CFCR_DLAB | cfcr);
385 
386 	dlbl = inb(comc_port + com_dlbl);
387 	dlbh = inb(comc_port + com_dlbh);
388 
389 	outb(comc_port + com_cfcr, cfcr);
390 
391 	divisor = dlbh << 8 | dlbl;
392 
393 	/* XXX there should be more sanity checking. */
394 	if (divisor == 0)
395 		return (COMSPEED);
396 	return (COMC_DIV2BPS(divisor));
397 }
398