xref: /openbsd/sys/arch/landisk/stand/boot/delay.c (revision 404b540a)
1 /*	$OpenBSD: delay.c,v 1.1 2006/10/06 21:48:50 mickey Exp $	*/
2 /*	$NetBSD: delay.c,v 1.1 2006/09/01 21:26:18 uwe Exp $	*/
3 
4 /*-
5  * Copyright (c) 2005 NONAKA Kimihiro
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>
31 #include <libsa.h>
32 
33 #include <sh/tmureg.h>
34 
35 #ifndef	TICK_CH
36 #define	TICK_CH	0
37 #endif
38 #if TICK_CH == 0
39 #define	TSTR	SH4_TSTR
40 #define	TCOR	SH4_TCOR0
41 #define	TCNT	SH4_TCNT0
42 #define	TCR	SH4_TCR0
43 #define	TSTR_CH	TSTR_STR0
44 #elif TICK_CH == 1
45 #define	TSTR	SH4_TSTR
46 #define	TCOR	SH4_TCOR1
47 #define	TCNT	SH4_TCNT1
48 #define	TCR	SH4_TCR1
49 #define	TSTR_CH	TSTR_STR1
50 #elif TICK_CH == 2
51 #define	TSTR	SH4_TSTR
52 #define	TCOR	SH4_TCOR2
53 #define	TCNT	SH4_TCNT2
54 #define	TCR	SH4_TCR2
55 #define	TSTR_CH	TSTR_STR2
56 #elif TICK_CH == 3
57 #define	TSTR	SH4_TSTR2
58 #define	TCOR	SH4_TCOR3
59 #define	TCNT	SH4_TCNT3
60 #define	TCR	SH4_TCR3
61 #define	TSTR_CH	SH4_TSTR2_STR3
62 #elif TICK_CH == 4
63 #define	TSTR	SH4_TSTR2
64 #define	TCOR	SH4_TCOR4
65 #define	TCNT	SH4_TCNT4
66 #define	TCR	SH4_TCR4
67 #define	TSTR_CH	SH4_TSTR2_STR4
68 #else
69 #error	TICK_CH != [01234]
70 #endif
71 
72 #ifndef	TICK_PRESC
73 #define	TICK_PRESC	1024
74 #endif
75 #if TICK_PRESC == 4
76 #define	TCR_TPSC	TCR_TPSC_P4
77 #elif TICK_PRESC == 16
78 #define	TCR_TPSC	TCR_TPSC_P16
79 #elif TICK_PRESC == 64
80 #define	TCR_TPSC	TCR_TPSC_P64
81 #elif TICK_PRESC == 256
82 #define	TCR_TPSC	TCR_TPSC_P256
83 #elif TICK_PRESC == 1024
84 #define	TCR_TPSC	SH4_TCR_TPSC_P1024
85 #else
86 #error	TICK_PRESC != 4, 16, 64, 256, 1024
87 #endif
88 
89 #define	TICKS_PER_SEC	(PCLOCK / TICK_PRESC)
90 #define	MS_PER_TICK	(1000000 / TICKS_PER_SEC)
91 
92 int
93 tick_init(void)
94 {
95 
96 	_reg_bclr_1(TSTR, TSTR_CH);
97 	_reg_write_2(TCR, TCR_TPSC);
98 	_reg_write_4(TCOR, 0xffffffff);
99 	_reg_write_4(TCNT, 0xffffffff);
100 	_reg_bset_1(TSTR, TSTR_CH);
101 
102 	return 0;
103 }
104 
105 void
106 tick_stop(void)
107 {
108 
109 	_reg_bclr_1(TSTR, TSTR_CH);
110 }
111 
112 uint32_t
113 gettick(void)
114 {
115 
116 	return ~(_reg_read_4(TCNT));
117 }
118 
119 void
120 delay(int ms)
121 {
122 	uint32_t base, now;
123 
124 	base = gettick();
125 	for (;;) {
126 		now = gettick();
127 		if (((now - base) / MS_PER_TICK) > ms) {
128 			break;
129 		}
130 	}
131 }
132