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1/* 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#ifdef __KERNEL__
19#include <linux/spinlock.h> /* spinlock_t */
20extern spinlock_t rtc_lock; /* serialize CMOS RAM access */
21
22/* Some RTCs extend the mc146818 register set to support alarms of more
23 * than 24 hours in the future; or dates that include a century code.
24 * This platform_data structure can pass this information to the driver.
25 */
26struct cmos_rtc_board_info {
27 u8 rtc_day_alarm; /* zero, or register index */
28 u8 rtc_mon_alarm; /* zero, or register index */
29 u8 rtc_century; /* zero, or register index */
30};
31#endif
32
33/**********************************************************************
34 * register summary
35 **********************************************************************/
36#define RTC_SECONDS 0
37#define RTC_SECONDS_ALARM 1
38#define RTC_MINUTES 2
39#define RTC_MINUTES_ALARM 3
40#define RTC_HOURS 4
41#define RTC_HOURS_ALARM 5
42/* RTC_*_alarm is always true if 2 MSBs are set */
43# define RTC_ALARM_DONT_CARE 0xC0
44
45#define RTC_DAY_OF_WEEK 6
46#define RTC_DAY_OF_MONTH 7
47#define RTC_MONTH 8
48#define RTC_YEAR 9
49
50/* control registers - Moto names
51 */
52#define RTC_REG_A 10
53#define RTC_REG_B 11
54#define RTC_REG_C 12
55#define RTC_REG_D 13
56
57/**********************************************************************
58 * register details
59 **********************************************************************/
60#define RTC_FREQ_SELECT RTC_REG_A
61
62/* update-in-progress - set to "1" 244 microsecs before RTC goes off the bus,
63 * reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,
64 * totalling to a max high interval of 2.228 ms.
65 */
66# define RTC_UIP 0x80
67# define RTC_DIV_CTL 0x70
68 /* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */
69# define RTC_REF_CLCK_4MHZ 0x00
70# define RTC_REF_CLCK_1MHZ 0x10
71# define RTC_REF_CLCK_32KHZ 0x20
72 /* 2 values for divider stage reset, others for "testing purposes only" */
73# define RTC_DIV_RESET1 0x60
74# define RTC_DIV_RESET2 0x70
75 /* Periodic intr. / Square wave rate select. 0=none, 1=32.8kHz,... 15=2Hz */
76# define RTC_RATE_SELECT 0x0F
77
78/**********************************************************************/
79#define RTC_CONTROL RTC_REG_B
80# define RTC_SET 0x80 /* disable updates for clock setting */
81# define RTC_PIE 0x40 /* periodic interrupt enable */
82# define RTC_AIE 0x20 /* alarm interrupt enable */
83# define RTC_UIE 0x10 /* update-finished interrupt enable */
84# define RTC_SQWE 0x08 /* enable square-wave output */
85# define RTC_DM_BINARY 0x04 /* all time/date values are BCD if clear */
86# define RTC_24H 0x02 /* 24 hour mode - else hours bit 7 means pm */
87# define RTC_DST_EN 0x01 /* auto switch DST - works f. USA only */
88
89/**********************************************************************/
90#define RTC_INTR_FLAGS RTC_REG_C
91/* caution - cleared by read */
92# define RTC_IRQF 0x80 /* any of the following 3 is active */
93# define RTC_PF 0x40
94# define RTC_AF 0x20
95# define RTC_UF 0x10
96
97/**********************************************************************/
98#define RTC_VALID RTC_REG_D
99# define RTC_VRT 0x80 /* valid RAM and time */
100/**********************************************************************/
101
102#ifndef ARCH_RTC_LOCATION /* Override by <asm/mc146818rtc.h>? */
103
104#define RTC_IO_EXTENT 0x8
105#define RTC_IOMAPPED 1 /* Default to I/O mapping. */
106
107#endif /* ARCH_RTC_LOCATION */
108
109#endif /* _MC146818RTC_H */