xref: /xnu-8792.61.2/bsd/dev/i386/km.c (revision 42e220869062b56f8d7d0726fd4c88954f87902c)
1 /*
2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*      Copyright (c) 1992 NeXT Computer, Inc.  All rights reserved.
29  *
30  * km.m - kernel keyboard/monitor module, procedural interface.
31  *
32  * HISTORY
33  */
34 
35 #include <sys/param.h>
36 #include <sys/tty.h>
37 
38 #include <machine/cons.h>
39 #include <sys/conf.h>
40 #include <sys/systm.h>
41 #include <sys/uio.h>
42 #include <sys/fcntl.h>          /* for kmopen */
43 #include <sys/errno.h>
44 #include <sys/proc.h>           /* for kmopen */
45 #include <sys/msgbuf.h>
46 #include <sys/time.h>
47 #include <dev/kmreg_com.h>
48 #include <pexpert/pexpert.h>
49 #include <pexpert/i386/boot.h>
50 
51 extern int hz;
52 
53 extern void console_write_char(char);
54 extern void console_write(char *, int);
55 
56 void    kminit(void);
57 void    cons_cinput(char ch);
58 
59 /*
60  * 'Global' variables, shared only by this file and conf.c.
61  */
62 struct tty *km_tty[1] = { 0 };
63 
64 /*
65  * this works early on, after initialize_screen() but before autoconf (and thus
66  * before we have a kmDevice).
67  */
68 int disableConsoleOutput;
69 
70 /*
71  * 'Global' variables, shared only by this file and kmDevice.m.
72  */
73 int initialized = 0;
74 
75 static int kmoutput(struct tty *tp);
76 static void kmstart(struct tty *tp);
77 
78 extern void KeyboardOpen(void);
79 
80 void
kminit(void)81 kminit(void)
82 {
83 	km_tty[0] = ttymalloc();
84 	km_tty[0]->t_dev = makedev(12, 0);
85 	initialized = 1;
86 }
87 
88 /*
89  * cdevsw interface to km driver.
90  */
91 int
kmopen(dev_t dev,int flag,__unused int devtype,proc_t pp)92 kmopen(dev_t dev, int flag, __unused int devtype, proc_t pp)
93 {
94 	int unit;
95 	struct tty *tp;
96 	struct winsize *wp;
97 	int ret;
98 
99 	unit = minor(dev);
100 	if (unit >= 1) {
101 		return ENXIO;
102 	}
103 
104 	tp = km_tty[unit];
105 
106 	tty_lock(tp);
107 
108 	tp->t_oproc = kmstart;
109 	tp->t_param = NULL;
110 	tp->t_dev = dev;
111 
112 	if (!(tp->t_state & TS_ISOPEN)) {
113 		tp->t_iflag = TTYDEF_IFLAG;
114 		tp->t_oflag = TTYDEF_OFLAG;
115 		tp->t_cflag = (CREAD | CS8 | CLOCAL);
116 		tp->t_lflag = TTYDEF_LFLAG;
117 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
118 		termioschars(&tp->t_termios);
119 		ttsetwater(tp);
120 	} else if ((tp->t_state & TS_XCLUDE) && proc_suser(pp)) {
121 		ret = EBUSY;
122 		goto out;
123 	}
124 
125 	tp->t_state |= TS_CARR_ON; /* lie and say carrier exists and is on. */
126 
127 	ret = ((*linesw[tp->t_line].l_open)(dev, tp));
128 	{
129 		PE_Video video;
130 		wp = &tp->t_winsize;
131 		/*
132 		 * Magic numbers.  These are CHARWIDTH and CHARHEIGHT
133 		 * from pexpert/i386/video_console.c
134 		 */
135 		wp->ws_xpixel = 8;
136 		wp->ws_ypixel = 16;
137 
138 		tty_unlock(tp);         /* XXX race window */
139 
140 		if (flag & O_POPUP) {
141 			PE_initialize_console(0, kPETextScreen);
142 		}
143 
144 		bzero(&video, sizeof(video));
145 		PE_current_console(&video);
146 
147 		tty_lock(tp);
148 
149 		if (video.v_display == FB_TEXT_MODE && video.v_width != 0 && video.v_height != 0) {
150 			wp->ws_col = video.v_width / wp->ws_xpixel;
151 			wp->ws_row = video.v_height / wp->ws_ypixel;
152 		} else {
153 			wp->ws_col = 100;
154 			wp->ws_row = 36;
155 		}
156 	}
157 
158 out:
159 	tty_unlock(tp);
160 
161 	return ret;
162 }
163 
164 int
kmclose(dev_t dev,int flag,__unused int mode,__unused proc_t p)165 kmclose(dev_t dev, int flag, __unused int mode, __unused proc_t p)
166 {
167 	int ret;
168 	struct tty *tp = km_tty[minor(dev)];
169 
170 	tty_lock(tp);
171 	ret = (*linesw[tp->t_line].l_close)(tp, flag);
172 	ttyclose(tp);
173 	tty_unlock(tp);
174 
175 	return ret;
176 }
177 
178 int
kmread(dev_t dev,struct uio * uio,int ioflag)179 kmread(dev_t dev, struct uio *uio, int ioflag)
180 {
181 	int ret;
182 	struct tty *tp = km_tty[minor(dev)];
183 
184 	tty_lock(tp);
185 	ret = (*linesw[tp->t_line].l_read)(tp, uio, ioflag);
186 	tty_unlock(tp);
187 
188 	return ret;
189 }
190 
191 int
kmwrite(dev_t dev,struct uio * uio,int ioflag)192 kmwrite(dev_t dev, struct uio *uio, int ioflag)
193 {
194 	int ret;
195 	struct tty *tp = km_tty[minor(dev)];
196 
197 	tty_lock(tp);
198 	ret = (*linesw[tp->t_line].l_write)(tp, uio, ioflag);
199 	tty_unlock(tp);
200 
201 	return ret;
202 }
203 
204 int
kmioctl(dev_t dev,u_long cmd,caddr_t data,int flag,proc_t p)205 kmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, proc_t p)
206 {
207 	int error = 0;
208 	struct tty *tp = km_tty[minor(dev)];
209 	struct winsize *wp;
210 
211 	tty_lock(tp);
212 
213 	switch (cmd) {
214 	case KMIOCSIZE:
215 		wp = (struct winsize *)data;
216 		*wp = tp->t_winsize;
217 		break;
218 
219 	case TIOCSWINSZ:
220 		/* Prevent changing of console size --
221 		 * this ensures that login doesn't revert to the
222 		 * termcap-defined size
223 		 */
224 		error = EINVAL;
225 		break;
226 
227 	/* Bodge in the CLOCAL flag as the km device is always local */
228 	case TIOCSETA_32:
229 	case TIOCSETAW_32:
230 	case TIOCSETAF_32:
231 	{
232 		struct termios32 *t = (struct termios32 *)data;
233 		t->c_cflag |= CLOCAL;
234 		/* No Break */
235 	}
236 		goto fallthrough;
237 	case TIOCSETA_64:
238 	case TIOCSETAW_64:
239 	case TIOCSETAF_64:
240 	{
241 		struct user_termios *t = (struct user_termios *)data;
242 		t->c_cflag |= CLOCAL;
243 		/* No Break */
244 	}
245 fallthrough:
246 	default:
247 		error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
248 		if (ENOTTY != error) {
249 			break;
250 		}
251 		error = ttioctl_locked(tp, cmd, data, flag, p);
252 		break;
253 	}
254 
255 	tty_unlock(tp);
256 
257 	return error;
258 }
259 
260 /*
261  * kmputc
262  *
263  * Output a character to the serial console driver via console_write_char(),
264  * which is exported by that driver.
265  *
266  * Locks:       Assumes tp in the calling tty driver code is locked on
267  *              entry, remains locked on exit
268  *
269  * Notes:       Called from kmoutput(); giving the locking output
270  *              assumptions here, this routine should be static (and
271  *              inlined, given there is only one call site).
272  */
273 int
kmputc(__unused dev_t dev,char c)274 kmputc(__unused dev_t dev, char c)
275 {
276 	if (!disableConsoleOutput && initialized) {
277 		/* OCRNL */
278 		if (c == '\n') {
279 			console_write_char('\r');
280 		}
281 		console_write_char(c);
282 	}
283 
284 	return 0;
285 }
286 
287 
288 /*
289  * Callouts from linesw.
290  */
291 
292 #define KM_LOWAT_DELAY  ((ns_time_t)1000)
293 
294 /*
295  * t_oproc for this driver; called from within the line discipline
296  *
297  * Locks:	Assumes tp is locked on entry, remains locked on exit
298  */
299 static void
kmstart(struct tty * tp)300 kmstart(struct tty *tp)
301 {
302 	if (tp->t_state & (TS_TIMEOUT | TS_BUSY | TS_TTSTOP)) {
303 		goto out;
304 	}
305 	if (tp->t_outq.c_cc == 0) {
306 		goto out;
307 	}
308 	tp->t_state |= TS_BUSY;
309 	kmoutput(tp);
310 	return;
311 
312 out:
313 	(*linesw[tp->t_line].l_start)(tp);
314 	return;
315 }
316 
317 /*
318  * One-shot output retry timeout from kmoutput(); re-calls kmoutput() at
319  * intervals until the output queue for the tty is empty, at which point
320  * the timeout is not rescheduled by kmoutput()
321  *
322  * This function must take the tty_lock() around the kmoutput() call; it
323  * ignores the return value.
324  */
325 static void
kmtimeout(void * arg)326 kmtimeout(void *arg)
327 {
328 	struct tty      *tp = (struct tty *)arg;
329 
330 	tty_lock(tp);
331 	(void)kmoutput(tp);
332 	tty_unlock(tp);
333 }
334 
335 /*
336  * kmoutput
337  *
338  * Locks:	Assumes tp is locked on entry, remains locked on exit
339  *
340  * Notes:	Called from kmstart() and kmtimeout(); kmtimeout() is a
341  *		timer initiated by this routine to deal with pending
342  *		output not yet flushed (output is flushed at a maximum
343  *		of sizeof(buf) charatcers at a time before dropping into
344  *		the timeout code).
345  */
346 static int
kmoutput(struct tty * tp)347 kmoutput(struct tty *tp)
348 {
349 	unsigned char   buf[80];        /* buffer; limits output per call */
350 	unsigned char   *cp;
351 	int             cc = -1;
352 
353 
354 	/* While there is data available to be output... */
355 	while (tp->t_outq.c_cc > 0) {
356 		cc = ndqb(&tp->t_outq, 0);
357 		if (cc == 0) {
358 			break;
359 		}
360 		/*
361 		 * attempt to output as many characters as are available,
362 		 * up to the available transfer buffer size.
363 		 */
364 		cc = min(cc, sizeof(buf));
365 		/* copy the output queue contents to the buffer */
366 		(void) q_to_b(&tp->t_outq, buf, cc);
367 		for (cp = buf; cp < &buf[cc]; cp++) {
368 			/* output the buffer one charatcer at a time */
369 			*cp = *cp & 0x7f;
370 		}
371 
372 		if (cc > 1) {
373 			console_write((char *)buf, cc);
374 		} else {
375 			kmputc(tp->t_dev, *buf);
376 		}
377 	}
378 	/*
379 	 * XXX This is likely not necessary, as the tty output queue is not
380 	 * XXX writeable while we hold the tty_lock().
381 	 */
382 	if (tp->t_outq.c_cc > 0) {
383 		timeout(kmtimeout, tp, hz);
384 	}
385 	tp->t_state &= ~TS_BUSY;
386 	/* Start the output processing for the line discipline */
387 	(*linesw[tp->t_line].l_start)(tp);
388 
389 	return 0;
390 }
391 
392 
393 /*
394  * cons_cinput
395  *
396  * Driver character input from the polled mode serial console driver calls
397  * this routine to input a character from the serial driver into the tty
398  * line discipline specific input processing receiv interrupt routine,
399  * l_rint().
400  *
401  * Locks:       Assumes that the tty_lock() is NOT held on the tp, so a
402  *              serial driver should NOT call this function as a result
403  *              of being called from a function which already holds the
404  *              lock; ECHOE will be handled at the line discipline, if
405  *              output echo processing is going to occur.
406  */
407 void
cons_cinput(char ch)408 cons_cinput(char ch)
409 {
410 	struct tty *tp = km_tty[0];     /* XXX */
411 
412 	tty_lock(tp);
413 	(*linesw[tp->t_line].l_rint)(ch, tp);
414 	tty_unlock(tp);
415 }
416