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>
64 #include <sys/sysctl.h>
68 #include <sys/timetc.h>
69 #include <sys/interrupt.h>
71 #include <machine/clock.h>
72 #include <machine/platform.h>
73 #include <machine/psl.h>
74 #include <machine/spr.h>
75 #include <machine/cpu.h>
76 #include <machine/intr.h>
77 #include <machine/md_var.h>
80 * Initially we assume a processor with a bus frequency of 12.5 MHz.
83 u_long ns_per_tick = 80;
84 static u_long ticks_per_sec = 12500000;
85 static long ticks_per_intr;
87 #define DIFF19041970 2082844800
89 static timecounter_get_t decr_get_timecount;
91 static struct timecounter decr_timecounter = {
92 decr_get_timecount, /* get_timecount */
94 ~0u, /* counter_mask */
96 "decrementer" /* name */
100 decr_intr(struct trapframe *frame)
104 * Check whether we are initialized.
110 * Interrupt handler must reset DIS to avoid getting another
111 * interrupt once EE is enabled.
113 mtspr(SPR_TSR, TSR_DIS);
115 CTR1(KTR_INTR, "%s: DEC interrupt", __func__);
117 if (PCPU_GET(cpuid) == 0)
118 hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
120 hardclock_cpu(TRAPF_USERMODE(frame));
122 statclock(TRAPF_USERMODE(frame));
124 profclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
142 if (platform_smp_get_bsp(&cpu) != 0)
143 platform_smp_first_cpu(&cpu);
144 ticks_per_sec = platform_timebase_freq(&cpu);
147 mtmsr(msr & ~(PSL_EE));
149 ns_per_tick = 1000000000 / ticks_per_sec;
150 ticks_per_intr = ticks_per_sec / hz;
152 mtdec(ticks_per_intr);
154 mtspr(SPR_DECAR, ticks_per_intr);
155 mtspr(SPR_TCR, mfspr(SPR_TCR) | TCR_DIE | TCR_ARE);
157 set_cputicker(mftb, ticks_per_sec, 0);
167 /* Set auto-reload value and enable DEC interrupts in TCR */
168 mtspr(SPR_DECAR, ticks_per_intr);
169 mtspr(SPR_TCR, mfspr(SPR_TCR) | TCR_DIE | TCR_ARE);
171 CTR2(KTR_INTR, "%s: set TCR=%p", __func__, mfspr(SPR_TCR));
179 decr_timecounter.tc_frequency = ticks_per_sec;
180 tc_init(&decr_timecounter);
184 decr_get_timecount(struct timecounter *tc)
193 * Wait for about n microseconds (at least!).
198 u_quad_t start, end, now;
201 end = start + (u_quad_t)ticks_per_sec / (1000000ULL / n);
204 } while (now < end || (now > start && end < start));
211 cpu_startprofclock(void)
218 cpu_stopprofclock(void)