comconsole.c revision 245848 
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: head/sys/boot/i386/libi386/comconsole.c 245848 2013-01-23 18:34:21Z jhb $");
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
48static void	comc_probe(struct console *cp);
49static int	comc_init(int arg);
50static void	comc_putchar(int c);
51static int	comc_getchar(void);
52static int	comc_getspeed(void);
53static int	comc_ischar(void);
54static int	comc_parseint(const char *string);
55static uint32_t comc_parse_pcidev(const char *string);
56static int	comc_pcidev_set(struct env_var *ev, int flags,
57		    const void *value);
58static int	comc_pcidev_handle(uint32_t locator);
59static int	comc_port_set(struct env_var *ev, int flags,
60		    const void *value);
61static void	comc_setup(int speed, int port);
62static int	comc_speed_set(struct env_var *ev, int flags,
63		    const void *value);
64
65static int	comc_curspeed;
66static int	comc_port = COMPORT;
67static uint32_t	comc_locator;
68
69struct console comconsole = {
70    "comconsole",
71    "serial port",
72    0,
73    comc_probe,
74    comc_init,
75    comc_putchar,
76    comc_getchar,
77    comc_ischar
78};
79
80static void
81comc_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, comc_speed_set,
110	    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, comc_port_set,
122	    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, comc_pcidev_set,
133	    env_nounset);
134    }
135    comc_setup(comc_curspeed, comc_port);
136}
137
138static int
139comc_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
150static void
151comc_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
162static int
163comc_getchar(void)
164{
165    return (comc_ischar() ? inb(comc_port + com_data) : -1);
166}
167
168static int
169comc_ischar(void)
170{
171    return (inb(comc_port + com_lsr) & LSR_RXRDY);
172}
173
174static int
175comc_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 ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) != 0 &&
185	comc_curspeed != speed)
186	comc_setup(speed, comc_port);
187
188    env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
189
190    return (CMD_OK);
191}
192
193static int
194comc_port_set(struct env_var *ev, int flags, const void *value)
195{
196    int port;
197
198    if (value == NULL || (port = comc_parseint(value)) <= 0) {
199	printf("Invalid port\n");
200	return (CMD_ERROR);
201    }
202
203    if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) != 0 &&
204	comc_port != port)
205	comc_setup(comc_curspeed, port);
206
207    env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
208
209    return (CMD_OK);
210}
211
212/*
213 * Input: bus:dev:func[:bar]. If bar is not specified, it is 0x10.
214 * Output: bar[24:16] bus[15:8] dev[7:3] func[2:0]
215 */
216static uint32_t
217comc_parse_pcidev(const char *string)
218{
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}
253
254static int
255comc_pcidev_handle(uint32_t locator)
256{
257	char intbuf[64];
258	uint32_t port;
259
260	if (biospci_read_config(locator & 0xffff,
261				(locator & 0xff0000) >> 16, 2, &port) == -1) {
262		printf("Cannot read bar at 0x%x\n", locator);
263		return (CMD_ERROR);
264	}
265	if (!PCI_BAR_IO(port)) {
266		printf("Memory bar at 0x%x\n", locator);
267		return (CMD_ERROR);
268	}
269        port &= PCIM_BAR_IO_BASE;
270
271	sprintf(intbuf, "%d", port);
272	unsetenv("comconsole_port");
273	env_setenv("comconsole_port", EV_VOLATILE, intbuf,
274		   comc_port_set, env_nounset);
275
276	comc_setup(comc_curspeed, port);
277	comc_locator = locator;
278
279	return (CMD_OK);
280}
281
282static int
283comc_pcidev_set(struct env_var *ev, int flags, const void *value)
284{
285	uint32_t locator;
286	int error;
287
288	if (value == NULL || (locator = comc_parse_pcidev(value)) <= 0) {
289		printf("Invalid pcidev\n");
290		return (CMD_ERROR);
291	}
292	if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) != 0 &&
293	    comc_locator != locator) {
294		error = comc_pcidev_handle(locator);
295		if (error != CMD_OK)
296			return (error);
297	}
298	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
299	return (CMD_OK);
300}
301
302static void
303comc_setup(int speed, int port)
304{
305    static int TRY_COUNT = 1000000;
306    char intbuf[64];
307    int tries;
308
309    unsetenv("hw.uart.console");
310    comc_curspeed = speed;
311    comc_port = port;
312
313    outb(comc_port + com_cfcr, CFCR_DLAB | COMC_FMT);
314    outb(comc_port + com_dlbl, COMC_BPS(speed) & 0xff);
315    outb(comc_port + com_dlbh, COMC_BPS(speed) >> 8);
316    outb(comc_port + com_cfcr, COMC_FMT);
317    outb(comc_port + com_mcr, MCR_RTS | MCR_DTR);
318
319    tries = 0;
320    do
321        inb(comc_port + com_data);
322    while (inb(comc_port + com_lsr) & LSR_RXRDY && ++tries < TRY_COUNT);
323
324    if (tries < TRY_COUNT) {
325	comconsole.c_flags |= (C_PRESENTIN | C_PRESENTOUT);
326	sprintf(intbuf, "io:%d,br:%d", comc_port, comc_curspeed);
327	env_setenv("hw.uart.console", EV_VOLATILE, intbuf, NULL, NULL);
328    } else
329	comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
330}
331
332static int
333comc_parseint(const char *speedstr)
334{
335    char *p;
336    int speed;
337
338    speed = strtol(speedstr, &p, 0);
339    if (p == speedstr || *p != '\0' || speed <= 0)
340	return (-1);
341
342    return (speed);
343}
344
345static int
346comc_getspeed(void)
347{
348	u_int	divisor;
349	u_char	dlbh;
350	u_char	dlbl;
351	u_char	cfcr;
352
353	cfcr = inb(comc_port + com_cfcr);
354	outb(comc_port + com_cfcr, CFCR_DLAB | cfcr);
355
356	dlbl = inb(comc_port + com_dlbl);
357	dlbh = inb(comc_port + com_dlbh);
358
359	outb(comc_port + com_cfcr, cfcr);
360
361	divisor = dlbh << 8 | dlbl;
362
363	/* XXX there should be more sanity checking. */
364	if (divisor == 0)
365		return (COMSPEED);
366	return (COMC_DIV2BPS(divisor));
367}
368