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wdenk4248acf2000-11-20 17:21:10 +00001/* mc146818rtc.h - register definitions for the Real-Time-Clock / CMOS RAM
2 * Copyright Torsten Duwe <duwe@informatik.uni-erlangen.de> 1993
3 * derived from Data Sheet, Copyright Motorola 1984 (!).
4 * It was written to be part of the Linux operating system.
5 */
6/* permission is hereby granted to copy, modify and redistribute this code
7 * in terms of the GNU Library General Public License, Version 2 or later,
8 * at your option.
9 */
10
11#ifndef _MC146818RTC_H
12#define _MC146818RTC_H
13
14#include <asm/io.h>
15#include <linux/rtc.h> /* get the user-level API */
16#include <asm/mc146818rtc.h> /* register access macros */
17
18/**********************************************************************
19 * register summary
20 **********************************************************************/
21#define RTC_SECONDS 0
22#define RTC_SECONDS_ALARM 1
23#define RTC_MINUTES 2
24#define RTC_MINUTES_ALARM 3
25#define RTC_HOURS 4
26#define RTC_HOURS_ALARM 5
27/* RTC_*_alarm is always true if 2 MSBs are set */
28# define RTC_ALARM_DONT_CARE 0xC0
29
30#define RTC_DAY_OF_WEEK 6
31#define RTC_DAY_OF_MONTH 7
32#define RTC_MONTH 8
33#define RTC_YEAR 9
34
35/* control registers - Moto names
36 */
37#define RTC_REG_A 10
38#define RTC_REG_B 11
39#define RTC_REG_C 12
40#define RTC_REG_D 13
41
42/**********************************************************************
43 * register details
44 **********************************************************************/
45#define RTC_FREQ_SELECT RTC_REG_A
46
47/* update-in-progress - set to "1" 244 microsecs before RTC goes off the bus,
48 * reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,
49 * totalling to a max high interval of 2.228 ms.
50 */
51# define RTC_UIP 0x80
52# define RTC_DIV_CTL 0x70
53 /* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */
54# define RTC_REF_CLCK_4MHZ 0x00
55# define RTC_REF_CLCK_1MHZ 0x10
56# define RTC_REF_CLCK_32KHZ 0x20
57 /* 2 values for divider stage reset, others for "testing purposes only" */
58# define RTC_DIV_RESET1 0x60
59# define RTC_DIV_RESET2 0x70
60 /* Periodic intr. / Square wave rate select. 0=none, 1=32.8kHz,... 15=2Hz */
61# define RTC_RATE_SELECT 0x0F
62
63/**********************************************************************/
64#define RTC_CONTROL RTC_REG_B
65# define RTC_SET 0x80 /* disable updates for clock setting */
66# define RTC_PIE 0x40 /* periodic interrupt enable */
67# define RTC_AIE 0x20 /* alarm interrupt enable */
68# define RTC_UIE 0x10 /* update-finished interrupt enable */
69# define RTC_SQWE 0x08 /* enable square-wave output */
70# define RTC_DM_BINARY 0x04 /* all time/date values are BCD if clear */
71# define RTC_24H 0x02 /* 24 hour mode - else hours bit 7 means pm */
72# define RTC_DST_EN 0x01 /* auto switch DST - works f. USA only */
73
74/**********************************************************************/
75#define RTC_INTR_FLAGS RTC_REG_C
76/* caution - cleared by read */
77# define RTC_IRQF 0x80 /* any of the following 3 is active */
78# define RTC_PF 0x40
79# define RTC_AF 0x20
80# define RTC_UF 0x10
81
82/**********************************************************************/
83#define RTC_VALID RTC_REG_D
84# define RTC_VRT 0x80 /* valid RAM and time */
85/**********************************************************************/
86
87/* example: !(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY)
88 * determines if the following two #defines are needed
89 */
90#ifndef BCD_TO_BIN
91#define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10)
92#endif
93
94#ifndef BIN_TO_BCD
95#define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10)
96#endif
97
98#endif /* _MC146818RTC_H */