2 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
3 * Copyright (C) 1995, 1996 TooLs GmbH.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
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.
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.
31 * $NetBSD: clock.c,v 1.9 2000/01/19 02:52:19 msaitoh Exp $
34 * Copyright (C) 2001 Benno Rice.
35 * All rights reserved.
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
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.
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.
58 #include <sys/cdefs.h>
59 __FBSDID("$FreeBSD$");
61 #include <sys/param.h>
62 #include <sys/systm.h>
63 #include <sys/kernel.h>
65 #include <sys/interrupt.h>
67 #include <sys/sysctl.h>
68 #include <sys/timetc.h>
70 #include <dev/ofw/openfirm.h>
72 #include <machine/clock.h>
73 #include <machine/cpu.h>
74 #include <machine/intr.h>
75 #include <machine/md_var.h>
76 #include <machine/smp.h>
79 * Initially we assume a processor with a bus frequency of 12.5 MHz.
81 u_long ns_per_tick = 80;
82 static u_long ticks_per_sec = 12500000;
83 static long ticks_per_intr;
85 static timecounter_get_t decr_get_timecount;
87 static struct timecounter decr_timecounter = {
88 decr_get_timecount, /* get_timecount */
90 ~0u, /* counter_mask */
92 "decrementer" /* name */
96 decr_intr(struct trapframe *frame)
101 * Check whether we are initialized.
107 * Based on the actual time delay since the last decrementer reload,
108 * we arrange for earlier interrupt next time.
110 __asm ("mfdec %0" : "=r"(tick));
111 for (nticks = 0; tick < 0; nticks++)
112 tick += ticks_per_intr;
115 while (nticks-- > 0) {
116 if (PCPU_GET(cpuid) == 0)
117 hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
119 hardclock_cpu(TRAPF_USERMODE(frame));
121 statclock(TRAPF_USERMODE(frame));
123 profclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
134 * Check the BSP's timebase frequency. Sometimes we can't find the BSP, so fall
135 * back to the first CPU in this case.
138 if (platform_smp_get_bsp(&cpu) != 0)
139 platform_smp_first_cpu(&cpu);
141 ticks_per_sec = platform_timebase_freq(&cpu);
144 mtmsr(msr & ~PSL_EE);
146 ns_per_tick = 1000000000 / ticks_per_sec;
147 ticks_per_intr = ticks_per_sec / hz;
148 mtdec(ticks_per_intr);
150 set_cputicker(mftb, ticks_per_sec, 0);
166 decr_timecounter.tc_frequency = ticks_per_sec;
167 tc_init(&decr_timecounter);
171 decr_get_timecount(struct timecounter *tc)
175 __asm __volatile("mftb %0" : "=r"(tb));
180 * Wait for about n microseconds (at least!).
188 ttb = tb + (n * 1000 + ns_per_tick - 1) / ns_per_tick;
197 cpu_startprofclock(void)
204 cpu_stopprofclock(void)