1/* $NetBSD: promcons.c,v 1.36 2011/04/24 16:26:52 rmind Exp $ */
2
3/*
4 * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
5 * All rights reserved.
6 *
7 * Author: Chris G. Demetriou
8 *
9 * Permission to use, copy, modify and distribute this software and
10 * its documentation is hereby granted, provided that both the copyright
11 * notice and this permission notice appear in all copies of the
12 * software, derivative works or modified versions, and any portions
13 * thereof, and that both notices appear in supporting documentation.
14 *
15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
17 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18 *
19 * Carnegie Mellon requests users of this software to return to
20 *
21 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
22 *  School of Computer Science
23 *  Carnegie Mellon University
24 *  Pittsburgh PA 15213-3890
25 *
26 * any improvements or extensions that they make and grant Carnegie the
27 * rights to redistribute these changes.
28 */
29
30#include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
31
32__KERNEL_RCSID(0, "$NetBSD: promcons.c,v 1.36 2011/04/24 16:26:52 rmind Exp $");
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/ioctl.h>
37#include <sys/select.h>
38#include <sys/tty.h>
39#include <sys/proc.h>
40#include <sys/file.h>
41#include <sys/uio.h>
42#include <sys/kernel.h>
43#include <sys/syslog.h>
44#include <sys/types.h>
45#include <sys/device.h>
46#include <sys/conf.h>
47#include <sys/kauth.h>
48
49#include <uvm/uvm_extern.h>
50
51#include <machine/cpuconf.h>
52#include <machine/prom.h>
53
54#ifdef _PMAP_MAY_USE_PROM_CONSOLE
55
56dev_type_open(promopen);
57dev_type_close(promclose);
58dev_type_read(promread);
59dev_type_write(promwrite);
60dev_type_ioctl(promioctl);
61dev_type_stop(promstop);
62dev_type_tty(promtty);
63dev_type_poll(prompoll);
64
65const struct cdevsw prom_cdevsw = {
66	promopen, promclose, promread, promwrite, promioctl,
67	promstop, promtty, prompoll, nommap, ttykqfilter, D_TTY
68};
69
70#define	PROM_POLL_HZ	50
71
72static struct  tty *prom_tty[1];
73static int polltime;
74
75void	promstart(struct tty *);
76void	promtimeout(void *);
77int	promparam(struct tty *, struct termios *);
78
79struct callout prom_ch;
80
81int
82promopen(dev_t dev, int flag, int mode, struct lwp *l)
83{
84	int unit = minor(dev);
85	struct tty *tp;
86	int s;
87	int error = 0, setuptimeout = 0;
88	static bool callo;
89
90	if (!callo) {
91		callout_init(&prom_ch, 0);
92		callo = true;
93	}
94
95	if (!pmap_uses_prom_console() || unit >= 1)
96		return ENXIO;
97
98	s = spltty();
99
100	if (!prom_tty[unit]) {
101		tp = prom_tty[unit] = tty_alloc();
102		tty_attach(tp);
103	} else
104		tp = prom_tty[unit];
105
106	tp->t_oproc = promstart;
107	tp->t_param = promparam;
108	tp->t_dev = dev;
109
110	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp)) {
111		splx(s);
112		return (EBUSY);
113	}
114
115	if ((tp->t_state & TS_ISOPEN) == 0) {
116		tp->t_state |= TS_CARR_ON;
117		ttychars(tp);
118		tp->t_iflag = TTYDEF_IFLAG;
119		tp->t_oflag = TTYDEF_OFLAG;
120		tp->t_cflag = TTYDEF_CFLAG|CLOCAL;
121		tp->t_lflag = TTYDEF_LFLAG;
122		tp->t_ispeed = tp->t_ospeed = 9600;
123		ttsetwater(tp);
124
125		setuptimeout = 1;
126	}
127
128	splx(s);
129
130	error = (*tp->t_linesw->l_open)(dev, tp);
131	if (error == 0 && setuptimeout) {
132		polltime = hz / PROM_POLL_HZ;
133		if (polltime < 1)
134			polltime = 1;
135		callout_reset(&prom_ch, polltime, promtimeout, tp);
136	}
137	return error;
138}
139
140int
141promclose(dev_t dev, int flag, int mode, struct lwp *l)
142{
143	int unit = minor(dev);
144	struct tty *tp = prom_tty[unit];
145
146	callout_stop(&prom_ch);
147	(*tp->t_linesw->l_close)(tp, flag);
148	ttyclose(tp);
149	return 0;
150}
151
152int
153promread(dev_t dev, struct uio *uio, int flag)
154{
155	struct tty *tp = prom_tty[minor(dev)];
156
157	return ((*tp->t_linesw->l_read)(tp, uio, flag));
158}
159
160int
161promwrite(dev_t dev, struct uio *uio, int flag)
162{
163	struct tty *tp = prom_tty[minor(dev)];
164
165	return ((*tp->t_linesw->l_write)(tp, uio, flag));
166}
167
168int
169prompoll(dev_t dev, int events, struct lwp *l)
170{
171	struct tty *tp = prom_tty[minor(dev)];
172
173	return ((*tp->t_linesw->l_poll)(tp, events, l));
174}
175
176int
177promioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
178{
179	int unit = minor(dev);
180	struct tty *tp = prom_tty[unit];
181	int error;
182
183	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
184	if (error != EPASSTHROUGH)
185		return error;
186	return ttioctl(tp, cmd, data, flag, l);
187}
188
189int
190promparam(struct tty *tp, struct termios *t)
191{
192
193	return 0;
194}
195
196void
197promstart(struct tty *tp)
198{
199	int s;
200
201	s = spltty();
202	if (tp->t_state & (TS_TTSTOP | TS_BUSY))
203		goto out;
204	ttypull(tp);
205	tp->t_state |= TS_BUSY;
206	while (tp->t_outq.c_cc != 0)
207		promcnputc(tp->t_dev, getc(&tp->t_outq));
208	tp->t_state &= ~TS_BUSY;
209out:
210	splx(s);
211}
212
213/*
214 * Stop output on a line.
215 */
216void
217promstop(struct tty *tp, int flag)
218{
219	int s;
220
221	s = spltty();
222	if (tp->t_state & TS_BUSY)
223		if ((tp->t_state & TS_TTSTOP) == 0)
224			tp->t_state |= TS_FLUSH;
225	splx(s);
226}
227
228void
229promtimeout(void *v)
230{
231	struct tty *tp = v;
232	u_char c;
233
234	while (promcnlookc(tp->t_dev, &c)) {
235		if (tp->t_state & TS_ISOPEN)
236			(*tp->t_linesw->l_rint)(c, tp);
237	}
238	callout_reset(&prom_ch, polltime, promtimeout, tp);
239}
240
241struct tty *
242promtty(dev_t dev)
243{
244
245	if (minor(dev) != 0)
246		panic("promtty: bogus");
247
248	return prom_tty[0];
249}
250
251#else /* _PMAP_MAY_USE_PROM_CONSOLE */
252
253/*
254 * If not defined _PMAP_MAY_USE_PROM_CONSOLE,
255 * this fake prom_cdevsw is attached to the kernel.
256 * NEVER REMOVE!
257 */
258const struct cdevsw prom_cdevsw = {
259	noopen, noclose, noread, nowrite, noioctl,
260	nostop, notty, nopoll, nommap,
261};
262
263#endif /* _PMAP_MAY_USE_PROM_CONSOLE */
264