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