xref: /freebsd/stand/i386/libi386/comconsole.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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 #include <stand.h>
28 #include <bootstrap.h>
29 #include <machine/cpufunc.h>
30 #include <dev/ic/ns16550.h>
31 #include <dev/pci/pcireg.h>
32 #include "libi386.h"
33 
34 #define COMC_FMT	0x3		/* 8N1 */
35 #define COMC_TXWAIT	0x40000		/* transmit timeout */
36 #define COMC_BPS(x)	(115200 / (x))	/* speed to DLAB divisor */
37 #define COMC_DIV2BPS(x)	(115200 / (x))	/* DLAB divisor to speed */
38 
39 #ifndef	COMPORT
40 #define COMPORT		0x3f8
41 #endif
42 #ifndef	COMSPEED
43 #define COMSPEED	115200
44 #endif
45 
46 static void	comc_probe(struct console *cp);
47 static int	comc_init(int arg);
48 static void	comc_putchar(int c);
49 static int	comc_getchar(void);
50 static int	comc_getspeed(void);
51 static int	comc_ischar(void);
52 static int	comc_parseint(const char *string);
53 static uint32_t comc_parse_pcidev(const char *string);
54 static int	comc_pcidev_set(struct env_var *ev, int flags,
55 		    const void *value);
56 static int	comc_pcidev_handle(uint32_t locator);
57 static int	comc_port_set(struct env_var *ev, int flags,
58 		    const void *value);
59 static void	comc_setup(int speed, int port);
60 static int	comc_speed_set(struct env_var *ev, int flags,
61 		    const void *value);
62 
63 static int	comc_curspeed;
64 static int	comc_port = COMPORT;
65 static uint32_t	comc_locator;
66 
67 struct console comconsole = {
68 	.c_name = "comconsole",
69 	.c_desc = "serial port",
70 	.c_flags = 0,
71 	.c_probe = comc_probe,
72 	.c_init = comc_init,
73 	.c_out = comc_putchar,
74 	.c_in = comc_getchar,
75 	.c_ready = comc_ischar
76 };
77 
78 static void
79 comc_probe(struct console *cp)
80 {
81 	char intbuf[16];
82 	char *cons, *env;
83 	int speed, port;
84 	uint32_t locator;
85 
86 	if (comc_curspeed == 0) {
87 		comc_curspeed = COMSPEED;
88 		/*
89 		 * Assume that the speed was set by an earlier boot loader if
90 		 * comconsole is already the preferred console.
91 		 */
92 		cons = getenv("console");
93 		if ((cons != NULL && strcmp(cons, comconsole.c_name) == 0) ||
94 		    getenv("boot_multicons") != NULL) {
95 			comc_curspeed = comc_getspeed();
96 		}
97 
98 		env = getenv("comconsole_speed");
99 		if (env != NULL) {
100 			speed = comc_parseint(env);
101 			if (speed > 0)
102 				comc_curspeed = speed;
103 		}
104 
105 		sprintf(intbuf, "%d", comc_curspeed);
106 		unsetenv("comconsole_speed");
107 		env_setenv("comconsole_speed", EV_VOLATILE, intbuf,
108 		    comc_speed_set, env_nounset);
109 
110 		env = getenv("comconsole_port");
111 		if (env != NULL) {
112 			port = comc_parseint(env);
113 			if (port > 0)
114 				comc_port = port;
115 		}
116 
117 		sprintf(intbuf, "%d", comc_port);
118 		unsetenv("comconsole_port");
119 		env_setenv("comconsole_port", EV_VOLATILE, intbuf,
120 		    comc_port_set, env_nounset);
121 
122 		env = getenv("comconsole_pcidev");
123 		if (env != NULL) {
124 			locator = comc_parse_pcidev(env);
125 			if (locator != 0)
126 				comc_pcidev_handle(locator);
127 		}
128 
129 		unsetenv("comconsole_pcidev");
130 		env_setenv("comconsole_pcidev", EV_VOLATILE, env,
131 		    comc_pcidev_set, env_nounset);
132 	}
133 	comc_setup(comc_curspeed, comc_port);
134 }
135 
136 static int
137 comc_init(int arg)
138 {
139 
140 	comc_setup(comc_curspeed, comc_port);
141 
142 	if ((comconsole.c_flags & (C_PRESENTIN | C_PRESENTOUT)) ==
143 	    (C_PRESENTIN | C_PRESENTOUT))
144 		return (CMD_OK);
145 	return (CMD_ERROR);
146 }
147 
148 static void
149 comc_putchar(int c)
150 {
151 	int wait;
152 
153 	for (wait = COMC_TXWAIT; wait > 0; wait--)
154 		if (inb(comc_port + com_lsr) & LSR_TXRDY) {
155 			outb(comc_port + com_data, (u_char)c);
156 			break;
157 		}
158 }
159 
160 static int
161 comc_getchar(void)
162 {
163 	return (comc_ischar() ? inb(comc_port + com_data) : -1);
164 }
165 
166 static int
167 comc_ischar(void)
168 {
169 	return (inb(comc_port + com_lsr) & LSR_RXRDY);
170 }
171 
172 static int
173 comc_speed_set(struct env_var *ev, int flags, const void *value)
174 {
175 	int speed;
176 
177 	if (value == NULL || (speed = comc_parseint(value)) <= 0) {
178 		printf("Invalid speed\n");
179 		return (CMD_ERROR);
180 	}
181 
182 	if (comc_curspeed != speed)
183 		comc_setup(speed, comc_port);
184 
185 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
186 
187 	return (CMD_OK);
188 }
189 
190 static int
191 comc_port_set(struct env_var *ev, int flags, const void *value)
192 {
193 	int port;
194 
195 	if (value == NULL || (port = comc_parseint(value)) <= 0) {
196 		printf("Invalid port\n");
197 		return (CMD_ERROR);
198 	}
199 
200 	if (comc_port != port)
201 		comc_setup(comc_curspeed, port);
202 
203 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
204 
205 	return (CMD_OK);
206 }
207 
208 /*
209  * Input: bus:dev:func[:bar]. If bar is not specified, it is 0x10.
210  * Output: bar[24:16] bus[15:8] dev[7:3] func[2:0]
211  */
212 static uint32_t
213 comc_parse_pcidev(const char *string)
214 {
215 #ifdef EFI
216 	/* We don't support PCI in EFI yet */
217 	return (0);
218 #else
219 	char *p, *p1;
220 	uint8_t bus, dev, func, bar;
221 	uint32_t locator;
222 	int pres;
223 
224 	pres = strtol(string, &p, 0);
225 	if (p == string || *p != ':' || pres < 0 )
226 		return (0);
227 	bus = pres;
228 	p1 = ++p;
229 
230 	pres = strtol(p1, &p, 0);
231 	if (p == string || *p != ':' || pres < 0 )
232 		return (0);
233 	dev = pres;
234 	p1 = ++p;
235 
236 	pres = strtol(p1, &p, 0);
237 	if (p == string || (*p != ':' && *p != '\0') || pres < 0 )
238 		return (0);
239 	func = pres;
240 
241 	if (*p == ':') {
242 		p1 = ++p;
243 		pres = strtol(p1, &p, 0);
244 		if (p == string || *p != '\0' || pres <= 0 )
245 			return (0);
246 		bar = pres;
247 	} else
248 		bar = 0x10;
249 
250 	locator = (bar << 16) | biospci_locator(bus, dev, func);
251 	return (locator);
252 #endif
253 }
254 
255 static int
256 comc_pcidev_handle(uint32_t locator)
257 {
258 #ifdef EFI
259 	/* We don't support PCI in EFI yet */
260 	return (CMD_ERROR);
261 #else
262 	char intbuf[64];
263 	uint32_t port;
264 
265 	if (biospci_read_config(locator & 0xffff,
266 	    (locator & 0xff0000) >> 16, BIOSPCI_32BITS, &port) == -1) {
267 		printf("Cannot read bar at 0x%x\n", locator);
268 		return (CMD_ERROR);
269 	}
270 
271 	/*
272 	 * biospci_read_config() sets port == 0xffffffff if the pcidev
273 	 * isn't found on the bus.  Check for 0xffffffff and return to not
274 	 * panic in BTX.
275 	 */
276 	if (port == 0xffffffff) {
277 		printf("Cannot find specified pcidev\n");
278 		return (CMD_ERROR);
279 	}
280 	if (!PCI_BAR_IO(port)) {
281 		printf("Memory bar at 0x%x\n", locator);
282 		return (CMD_ERROR);
283 	}
284         port &= PCIM_BAR_IO_BASE;
285 
286 	sprintf(intbuf, "%d", port);
287 	unsetenv("comconsole_port");
288 	env_setenv("comconsole_port", EV_VOLATILE, intbuf,
289 		   comc_port_set, env_nounset);
290 
291 	comc_setup(comc_curspeed, port);
292 	comc_locator = locator;
293 
294 	return (CMD_OK);
295 #endif
296 }
297 
298 static int
299 comc_pcidev_set(struct env_var *ev, int flags, const void *value)
300 {
301 	uint32_t locator;
302 	int error;
303 
304 	if (value == NULL || (locator = comc_parse_pcidev(value)) <= 0) {
305 		printf("Invalid pcidev\n");
306 		return (CMD_ERROR);
307 	}
308 	if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) != 0 &&
309 	    comc_locator != locator) {
310 		error = comc_pcidev_handle(locator);
311 		if (error != CMD_OK)
312 			return (error);
313 	}
314 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
315 	return (CMD_OK);
316 }
317 
318 static void
319 comc_setup(int speed, int port)
320 {
321 	static int TRY_COUNT = 1000000;
322 	char intbuf[64];
323 	int tries;
324 
325 	comc_curspeed = speed;
326 	comc_port = port;
327 	if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) == 0)
328 		return;
329 
330 	unsetenv("hw.uart.console");
331 
332 #define	COMC_TEST	0xbb
333 	/*
334 	 * Write byte to scratch register and read it out.
335 	 */
336 	outb(comc_port + com_scr, COMC_TEST);
337 	if (inb(comc_port + com_scr) != COMC_TEST) {
338 		comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
339 		return;
340 	}
341 
342 	outb(comc_port + com_cfcr, CFCR_DLAB | COMC_FMT);
343 	outb(comc_port + com_dlbl, COMC_BPS(speed) & 0xff);
344 	outb(comc_port + com_dlbh, COMC_BPS(speed) >> 8);
345 	outb(comc_port + com_cfcr, COMC_FMT);
346 	outb(comc_port + com_mcr, MCR_RTS | MCR_DTR);
347 
348 	tries = 0;
349 	do
350 		inb(comc_port + com_data);
351 	while (inb(comc_port + com_lsr) & LSR_RXRDY && ++tries < TRY_COUNT);
352 
353 	if (tries < TRY_COUNT) {
354 		comconsole.c_flags |= (C_PRESENTIN | C_PRESENTOUT);
355 		sprintf(intbuf, "io:%d,br:%d", comc_port, comc_curspeed);
356 		env_setenv("hw.uart.console", EV_VOLATILE, intbuf, NULL, NULL);
357 	} else
358 		comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
359 }
360 
361 static int
362 comc_parseint(const char *speedstr)
363 {
364 	char *p;
365 	int speed;
366 
367 	speed = strtol(speedstr, &p, 0);
368 	if (p == speedstr || *p != '\0' || speed <= 0)
369 		return (-1);
370 
371 	return (speed);
372 }
373 
374 static int
375 comc_getspeed(void)
376 {
377 	u_int	divisor;
378 	u_char	dlbh;
379 	u_char	dlbl;
380 	u_char	cfcr;
381 
382 	cfcr = inb(comc_port + com_cfcr);
383 	outb(comc_port + com_cfcr, CFCR_DLAB | cfcr);
384 
385 	dlbl = inb(comc_port + com_dlbl);
386 	dlbh = inb(comc_port + com_dlbh);
387 
388 	outb(comc_port + com_cfcr, cfcr);
389 
390 	divisor = dlbh << 8 | dlbl;
391 
392 	/* XXX there should be more sanity checking. */
393 	if (divisor == 0)
394 		return (COMSPEED);
395 	return (COMC_DIV2BPS(divisor));
396 }
397