xref: /netbsd/sys/arch/sparc64/sparc64/timerreg.h (revision bf9ec67e)
1 /*	$NetBSD: timerreg.h,v 1.3 1999/06/05 05:10:01 mrg Exp $ */
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This software was developed by the Computer Systems Engineering group
8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9  * contributed to Berkeley.
10  *
11  * All advertising materials mentioning features or use of this software
12  * must display the following acknowledgement:
13  *	This product includes software developed by the University of
14  *	California, Lawrence Berkeley Laboratory.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  * 3. All advertising materials mentioning features or use of this software
25  *    must display the following acknowledgement:
26  *	This product includes software developed by the University of
27  *	California, Berkeley and its contributors.
28  * 4. Neither the name of the University nor the names of its contributors
29  *    may be used to endorse or promote products derived from this software
30  *    without specific prior written permission.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
33  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
36  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42  * SUCH DAMAGE.
43  *
44  *	@(#)timerreg.h	8.1 (Berkeley) 6/11/93
45  */
46 
47 /*
48  * Sun-4c counter/timer registers.  The timers are implemented within
49  * the cache chip (!).  The counter and limit fields below could be
50  * defined as:
51  *
52  *	struct {
53  *		u_int	t_limit:1,	// limit reached
54  *			t_usec:21,	// counter value in microseconds
55  *			t_mbz:10;	// always zero
56  *	};
57  *
58  * but this is more trouble than it is worth.
59  *
60  * These timers work in a rather peculiar fashion.  Most clock counters
61  * run to 0 (as, e.g., on the VAX, where the ICR counts up to 0 from a
62  * large unsigned number).  On the Sun-4c, it counts up to a limit.  But
63  * for some reason, when it reaches the limit, it resets to 1, not 0.
64  * Thus, if the limit is set to 4, the counter counts like this:
65  *
66  *	1, 2, 3, 1, 2, 3, ...
67  *
68  * and if we want to divide by N we must set the limit register to N+1.
69  *
70  * Sun-4m counters/timer registers are similar, with these exceptions:
71  *
72  *	- the limit and counter registers have changed positions..
73  *	- both limit and counter registers are 22 bits wide, but
74  *	  they count in 500ns increments (bit 9 being the least
75  *	  significant bit).
76  *
77  *	  Note that we still use the `sun4c' masks and shifts to compute
78  *	  the bit pattern, given the tick period in microseconds, resulting
79  *	  in a limit value that is 1 too high. This means that (with HZ=100)
80  *	  the clock will err on the slow side by 500ns/10ms (or 0.00005 %).
81  *	  We dont bother.
82  *
83  * Sun-4u counters/timer are similar but:
84  *
85  *	- the registers have been shuffled around once again.  We need
86  *	  to use offsets from the 3 addresses the ROM provides us.
87  *	- The counters are 28 bits wide with 1us accuracy.
88  *	- You can make them do funky things with the limit register
89  *	- They have standard 64-bit SBUS control registers.
90  *
91  * There is a problem on the Ultra5 and Ultra10.  As the PCI controller
92  * doesn't include the timer, there are no `counter-timer' nodes here
93  * and so we must use %tick.
94  */
95 #ifndef _LOCORE
96 struct timer_4 {
97 	volatile int	t_counter;		/* counter reg */
98 	volatile int	t_limit;		/* limit reg */
99 };
100 
101 struct timerreg_4 {
102 	struct	timer_4 t_c10;		/* counter that interrupts at ipl 10 */
103 	struct	timer_4 t_c14;		/* counter that interrupts at ipl 14 */
104 };
105 
106 struct timer_4m {		/* counter that interrupts at ipl 10 */
107 	volatile int	t_limit;		/* limit register */
108 	volatile int	t_counter;		/* counter register */
109 	volatile int	t_limit_nr;		/* limit reg, non-resetting */
110 	volatile int	t_reserved;
111 	volatile int	t_cfg;			/* a configuration register */
112 /*
113  * Note: The SparcClassic manual only defines this one bit
114  * I suspect there are more in multi-processor machines.
115  */
116 #define TMR_CFG_USER	1
117 };
118 
119 struct timer_4u {
120 	volatile int64_t t_count;		/* counter reg */
121 	volatile int64_t t_limit;		/* limit reg */
122 
123 #define TMR_LIM_IEN		0x80000000		/* interrupt enable bit */
124 #define TMR_LIM_RELOAD		0x40000000		/* reload counter to 0 */
125 #define TMR_LIM_PERIODIC	0x20000000		/* reset when limit is reached */
126 #define TMR_LIM_MASK		0x1fffffff
127 };
128 
129 struct timerreg_4u {
130 	struct timer_4u*	t_timer;		/* There are two of them */
131 	volatile int64_t*	t_clrintr;		/* There are two of these, too. */
132 	volatile int64_t*	t_mapintr;		/* Same here. */
133 };
134 
135 struct counter_4m {		/* counter that interrupts at ipl 14 */
136 	volatile int	t_limit;		/* limit register */
137 	volatile int	t_counter;		/* counter register */
138 	volatile int	t_limit_nr;		/* limit reg, non-resetting */
139 	volatile int	t_ss;			/* Start/Stop register */
140 #define TMR_USER_RUN	1
141 };
142 
143 #endif /* _LOCORE */
144 
145 #define	TMR_LIMIT	0x80000000	/* counter reached its limit */
146 #define	TMR_SHIFT	10		/* shift to obtain microseconds */
147 #define	TMR_MASK	0x1fffff	/* 21 bits */
148 
149 /* Compute a limit that causes the timer to fire every n microseconds. */
150 /* #define	tmr_ustolim(n)	(((n) + 1) << TMR_SHIFT) */
151 #define	tmr_ustolim(n)	((n))
152 
153 /*efine	TMR_SHIFT4M	9		-* shift to obtain microseconds */
154 /*efine tmr_ustolim(n)	(((2*(n)) + 1) << TMR_SHIFT4M)*/
155 
156 
157 
158