clock.c revision 170036 
1/*-
2 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
3 * Copyright (C) 1995, 1996 TooLs GmbH.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 *    must display the following acknowledgement:
16 *	This product includes software developed by TooLs GmbH.
17 * 4. The name of TooLs GmbH may not be used to endorse or promote products
18 *    derived from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 *
31 *	$NetBSD: clock.c,v 1.9 2000/01/19 02:52:19 msaitoh Exp $
32 */
33/*
34 * Copyright (C) 2001 Benno Rice.
35 * All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 *    notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 *    notice, this list of conditions and the following disclaimer in the
44 *    documentation and/or other materials provided with the distribution.
45 *
46 * THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
47 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
48 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
49 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
50 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
51 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
52 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
53 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
54 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
55 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56 */
57
58#include <sys/cdefs.h>
59__FBSDID("$FreeBSD: head/sys/powerpc/aim/clock.c 170036 2007-05-27 21:05:35Z marcel $");
60
61#include <sys/param.h>
62#include <sys/systm.h>
63#include <sys/kernel.h>
64#include <sys/sysctl.h>
65#include <sys/bus.h>
66#include <sys/clock.h>
67#include <sys/timetc.h>
68#include <sys/interrupt.h>
69
70#include <dev/ofw/openfirm.h>
71
72#include <machine/clock.h>
73#include <machine/cpu.h>
74#include <machine/intr.h>
75#include <machine/md_var.h>
76
77/*
78 * Initially we assume a processor with a bus frequency of 12.5 MHz.
79 */
80u_int			tickspending;
81u_long			ns_per_tick = 80;
82static u_long		ticks_per_sec = 12500000;
83static long		ticks_per_intr;
84static volatile u_long	lasttb;
85
86#define	DIFF19041970	2082844800
87
88static int		clockinitted = 0;
89
90static timecounter_get_t	decr_get_timecount;
91
92static struct timecounter	decr_timecounter = {
93	decr_get_timecount,	/* get_timecount */
94	0,			/* no poll_pps */
95	~0u,			/* counter_mask */
96	0,			/* frequency */
97	"decrementer"		/* name */
98};
99
100void
101inittodr(time_t base)
102{
103	time_t		deltat;
104	u_int		rtc_time;
105	struct timespec	ts;
106	phandle_t	phandle;
107	ihandle_t	ihandle;
108	char		rtcpath[128];
109	u_int		rtcsecs;
110
111	/*
112	 * If we can't read from RTC, use the fs time.
113	 */
114	phandle = OF_finddevice("rtc");
115	if (phandle != -1) {
116		OF_package_to_path(phandle, rtcpath, sizeof(rtcpath));
117		ihandle = OF_open(rtcpath);
118		if (ihandle != -1) {
119			if (OF_call_method("read-rtc", ihandle,
120			    0, 1, &rtcsecs))
121				printf("RTC call method error\n");
122			else {
123				ts.tv_sec = rtcsecs - DIFF19041970;
124				ts.tv_nsec = 0;
125				tc_setclock(&ts);
126				return;
127			}
128		}
129	}
130
131	{
132		ts.tv_sec = base;
133		ts.tv_nsec = 0;
134		tc_setclock(&ts);
135		return;
136	}
137	clockinitted = 1;
138	ts.tv_sec = rtc_time - DIFF19041970;
139
140	deltat = ts.tv_sec - base;
141	if (deltat < 0) {
142		deltat = -deltat;
143	}
144	if (deltat < 2 * SECDAY) {
145		tc_setclock(&ts);
146		return;
147	}
148
149	printf("WARNING: clock %s %d days",
150	    ts.tv_sec < base ? "lost" : "gained", (int)(deltat / SECDAY));
151
152	printf(" -- CHECK AND RESET THE DATE!\n");
153}
154
155/*
156 * Similar to the above
157 */
158void
159resettodr()
160{
161
162}
163
164void
165decr_intr(struct trapframe *frame)
166{
167	u_long		tb;
168	long		tick;
169	int		nticks;
170
171	/*
172	 * Check whether we are initialized.
173	 */
174	if (!ticks_per_intr)
175		return;
176
177	/*
178	 * Based on the actual time delay since the last decrementer reload,
179	 * we arrange for earlier interrupt next time.
180	 */
181	__asm ("mftb %0; mfdec %1" : "=r"(tb), "=r"(tick));
182	for (nticks = 0; tick < 0; nticks++)
183		tick += ticks_per_intr;
184	mtdec(tick);
185	/*
186	 * lasttb is used during microtime. Set it to the virtual
187	 * start of this tick interval.
188	 */
189	lasttb = tb + tick - ticks_per_intr;
190
191	nticks += tickspending;
192	tickspending = 0;
193
194	/*
195	 * Reenable interrupts
196	 */
197#if 0
198	msr = mfmsr();
199	mtmsr(msr | PSL_EE | PSL_RI);
200#endif
201	/*
202	 * Do standard timer interrupt stuff.
203	 * Do softclock stuff only on the last iteration.
204	 */
205#if 0
206	while (--nticks > 0) {
207		hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
208	}
209#endif
210	hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
211}
212
213void
214decr_init(void)
215{
216	int qhandle, phandle;
217	char name[32];
218	unsigned int msr;
219
220	phandle = 0;
221
222	/*
223	 * Get this info during autoconf?				XXX
224	 */
225	for (qhandle = OF_peer(0); qhandle; qhandle = phandle) {
226		if (OF_getprop(qhandle, "device_type", name, sizeof name) >= 0
227		    && !strcmp(name, "cpu")
228		    && OF_getprop(qhandle, "timebase-frequency",
229				  &ticks_per_sec, sizeof ticks_per_sec) >= 0) {
230			/*
231			 * Should check for correct CPU here?		XXX
232			 */
233			msr = mfmsr();
234			mtmsr(msr & ~(PSL_EE|PSL_RI));
235
236			decr_timecounter.tc_frequency = ticks_per_sec;
237			tc_init(&decr_timecounter);
238
239			ns_per_tick = 1000000000 / ticks_per_sec;
240			ticks_per_intr = ticks_per_sec / hz;
241			__asm __volatile ("mftb %0" : "=r"(lasttb));
242			mtdec(ticks_per_intr);
243
244			mtmsr(msr);
245
246			break;
247		}
248		if ((phandle = OF_child(qhandle)))
249			continue;
250		while (qhandle) {
251			if ((phandle = OF_peer(qhandle)))
252				break;
253			qhandle = OF_parent(qhandle);
254		}
255	}
256	if (!phandle)
257		panic("no cpu node");
258}
259
260static __inline u_quad_t
261mftb(void)
262{
263	u_long		scratch;
264	u_quad_t	tb;
265
266	__asm ("1: mftbu %0; mftb %0+1; mftbu %1; cmpw 0,%0,%1; bne 1b"
267	      : "=r"(tb), "=r"(scratch));
268	return tb;
269}
270
271static unsigned
272decr_get_timecount(struct timecounter *tc)
273{
274	return mftb();
275}
276
277/*
278 * Wait for about n microseconds (at least!).
279 */
280void
281DELAY(int n)
282{
283	u_quad_t	tb, ttb;
284
285	tb = mftb();
286	ttb = tb + (n * 1000 + ns_per_tick - 1) / ns_per_tick;
287	while (tb < ttb)
288		tb = mftb();
289}
290
291/*
292 * Nothing to do.
293 */
294void
295cpu_startprofclock(void)
296{
297
298	/* Do nothing */
299}
300
301void
302cpu_stopprofclock(void)
303{
304}
305
306/*
307 * XXX Needed by syscons
308 */
309int
310sysbeep(int pitch, int period)
311{
312
313	return (0);
314}
315