include/linux/mc146818rtc.h

/* */
   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 #include <asm/io.h>
  14 
  15 #define RTC_PORT(x)     (0x70 + (x))
  16 #define RTC_ADDR(x)     (0x80 | (x))
  17 #define RTC_ALWAYS_BCD  1
  18 
  19 /*
  20  * The Alpha Jensen hardware for some rather strange reason puts
  21  * the RTC clock at 0x170 instead of 0x70. Probably due to some
  22  * misguided idea about using 0x70 for NMI stuff.
  23  */
  24 #ifdef __alpha__
  25 #undef RTC_PORT
  26 #undef RTC_ADDR
  27 #undef RTC_ALWAYS_BCD
  28 #define RTC_PORT(x)     (0x170+(x))
  29 #define RTC_ADDR(x)     (x)
  30 #define RTC_ALWAYS_BCD  0
  31 #endif
  32 
  33 #define CMOS_READ(addr) ({ \
  34 outb_p(RTC_ADDR(addr),RTC_PORT(0)); \
  35 inb_p(RTC_PORT(1)); \
  36 })
  37 #define CMOS_WRITE(val, addr) ({ \
  38 outb_p(RTC_ADDR(addr),RTC_PORT(0)); \
  39 outb_p(val,RTC_PORT(1)); \
  40 })
  41 
  42 /**********************************************************************
  43  * register summary
  44  **********************************************************************/
  45 #define RTC_SECONDS             0
  46 #define RTC_SECONDS_ALARM       1
  47 #define RTC_MINUTES             2
  48 #define RTC_MINUTES_ALARM       3
  49 #define RTC_HOURS               4
  50 #define RTC_HOURS_ALARM         5
  51 /* RTC_*_alarm is always true if 2 MSBs are set */
  52 # define RTC_ALARM_DONT_CARE    0xC0
  53 
  54 #define RTC_DAY_OF_WEEK         6
  55 #define RTC_DAY_OF_MONTH        7
  56 #define RTC_MONTH               8
  57 #define RTC_YEAR                9
  58 
  59 /* control registers - Moto names
  60  */
  61 #define RTC_REG_A               10
  62 #define RTC_REG_B               11
  63 #define RTC_REG_C               12
  64 #define RTC_REG_D               13
  65 
  66 /**********************************************************************
  67  * register details
  68  **********************************************************************/
  69 #define RTC_FREQ_SELECT RTC_REG_A
  70 
  71 /* update-in-progress  - set to "1" 244 microsecs before RTC goes off the bus,
  72  * reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,
  73  * totalling to a max high interval of 2.228 ms.
  74  */
  75 # define RTC_UIP                0x80
  76 # define RTC_DIV_CTL            0x70
  77    /* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */
  78 #  define RTC_REF_CLCK_4MHZ     0x00
  79 #  define RTC_REF_CLCK_1MHZ     0x10
  80 #  define RTC_REF_CLCK_32KHZ    0x20
  81    /* 2 values for divider stage reset, others for "testing purposes only" */
  82 #  define RTC_DIV_RESET1        0x60
  83 #  define RTC_DIV_RESET2        0x70
  84   /* Periodic intr. / Square wave rate select. 0=none, 1=32.8kHz,... 15=2Hz */
  85 # define RTC_RATE_SELECT        0x0F
  86 
  87 /**********************************************************************/
  88 #define RTC_CONTROL     RTC_REG_B
  89 # define RTC_SET 0x80           /* disable updates for clock setting */
  90 # define RTC_PIE 0x40           /* periodic interrupt enable */
  91 # define RTC_AIE 0x20           /* alarm interrupt enable */
  92 # define RTC_UIE 0x10           /* update-finished interrupt enable */
  93 # define RTC_SQWE 0x08          /* enable square-wave output */
  94 # define RTC_DM_BINARY 0x04     /* all time/date values are BCD if clear */
  95 # define RTC_24H 0x02           /* 24 hour mode - else hours bit 7 means pm */
  96 # define RTC_DST_EN 0x01        /* auto switch DST - works f. USA only */
  97 
  98 /**********************************************************************/
  99 #define RTC_INTR_FLAGS  RTC_REG_C
 100 /* caution - cleared by read */
 101 # define RTC_IRQF 0x80          /* any of the following 3 is active */
 102 # define RTC_PF 0x40
 103 # define RTC_AF 0x20
 104 # define RTC_UF 0x10
 105 
 106 /**********************************************************************/
 107 #define RTC_VALID       RTC_REG_D
 108 # define RTC_VRT 0x80           /* valid RAM and time */
 109 /**********************************************************************/
 110 
 111 /* example: !(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) 
 112  * determines if the following two #defines are needed
 113  */
 114 #ifndef BCD_TO_BIN
 115 #define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10)
 116 #endif
 117 
 118 #ifndef BIN_TO_BCD
 119 #define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10)
 120 #endif
 121 
 122 #endif /* _MC146818RTC_H */
/* */
root/include/linux/mc146818rtc.h

INCLUDED FROM
