/* $NetBSD: mc146818reg.h,v 1.9 2006/03/08 23:46:25 lukem Exp $ */ /* * Copyright (c) 1995 Carnegie-Mellon University. * All rights reserved. * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ /* * Definitions for the Motorola MC146818A Real Time Clock. * They also apply for the (compatible) Dallas Semiconductor DS1287A RTC. * * Though there are undoubtedly other (better) sources, this material was * culled from the DEC "KN121 System Module Programmer's Reference * Information." * * The MC146818A has 16 registers. The first 10 contain time-of-year * and alarm data. The rest contain various control and status bits. * * To read or write the registers, one writes the register number to * the RTC's control port, then either reads from or writes the new * data to the RTC's data port. Since the locations of these ports * and the method used to access them can be machine-dependent, the * low-level details of reading and writing the RTC's registers are * handled by machine-specific functions. * * The time-of-year and alarm data can be expressed in either binary * or BCD, and they are selected by a bit in register B. * * The "hour" time-of-year and alarm fields can either be expressed in * AM/PM format, or in 24-hour format. If AM/PM format is chosen, the * hour fields can have the values: 1-12 and 81-92 (the latter being * PM). If the 24-hour format is chosen, they can have the values * 0-24. The hour format is selectable by a bit in register B. * (XXX IS AM/PM MODE DESCRIPTION CORRECT?) * * It is assumed the if systems are going to use BCD (rather than * binary) mode, or AM/PM hour format, they'll do the appropriate * conversions in machine-dependent code. Also, if the clock is * switched between BCD and binary mode, or between AM/PM mode and * 24-hour mode, the time-of-day and alarm registers are NOT * automatically reset; they must be reprogrammed with correct values. */ /* XXX not yet all port switch to MI mc146818(4) with todr(9) support */ #if defined(arc) #define USE_TODR_MCCLOCK #endif /* * The registers, and the bits within each register. */ #define MC_SEC 0x0 /* Time of year: seconds (0-59) */ #define MC_ASEC 0x1 /* Alarm: seconds */ #define MC_MIN 0x2 /* Time of year: minutes (0-59) */ #define MC_AMIN 0x3 /* Alarm: minutes */ #define MC_HOUR 0x4 /* Time of year: hour (see above) */ #define MC_AHOUR 0x5 /* Alarm: hour */ #define MC_DOW 0x6 /* Time of year: day of week (1-7) */ #define MC_DOM 0x7 /* Time of year: day of month (1-31) */ #define MC_MONTH 0x8 /* Time of year: month (1-12) */ #define MC_YEAR 0x9 /* Time of year: year in century (0-99) */ #define MC_REGA 0xa /* Control register A */ #define MC_REGA_RSMASK 0x0f /* Interrupt rate select mask (see below) */ #define MC_REGA_DVMASK 0x70 /* Divisor select mask (see below) */ #define MC_REGA_UIP 0x80 /* Update in progress; read only. */ #define MC_REGB 0xb /* Control register B */ #define MC_REGB_DSE 0x01 /* Daylight Savings Enable */ #define MC_REGB_24HR 0x02 /* 24-hour mode (AM/PM mode when clear) */ #define MC_REGB_BINARY 0x04 /* Binary mode (BCD mode when clear) */ #define MC_REGB_SQWE 0x08 /* Square Wave Enable */ #define MC_REGB_UIE 0x10 /* Update End interrupt enable */ #define MC_REGB_AIE 0x20 /* Alarm interrupt enable */ #define MC_REGB_PIE 0x40 /* Periodic interrupt enable */ #define MC_REGB_SET 0x80 /* Allow time to be set; stops updates */ #define MC_REGC 0xc /* Control register C */ /* MC_REGC_UNUSED 0x0f UNUSED */ #define MC_REGC_UF 0x10 /* Update End interrupt flag */ #define MC_REGC_AF 0x20 /* Alarm interrupt flag */ #define MC_REGC_PF 0x40 /* Periodic interrupt flag */ #define MC_REGC_IRQF 0x80 /* Interrupt request pending flag */ #define MC_REGD 0xd /* Control register D */ /* MC_REGD_UNUSED 0x7f UNUSED */ #define MC_REGD_VRT 0x80 /* Valid RAM and Time bit */ #define MC_NREGS 0xe /* 14 registers; CMOS follows */ #define MC_NTODREGS 0xa /* 10 of those regs are for TOD and alarm */ #define MC_NVRAM_START 0xe /* start of NVRAM: offset 14 */ #define MC_NVRAM_SIZE 50 /* 50 bytes of NVRAM */ /* * Periodic Interrupt Rate Select constants (Control register A) */ #define MC_RATE_NONE 0x0 /* No periodic interrupt */ #define MC_RATE_1 0x1 /* 256 Hz if MC_BASE_32_KHz, else 32768 Hz */ #define MC_RATE_2 0x2 /* 128 Hz if MC_BASE_32_KHz, else 16384 Hz */ #define MC_RATE_8192_Hz 0x3 /* 122.070 us period */ #define MC_RATE_4096_Hz 0x4 /* 244.141 us period */ #define MC_RATE_2048_Hz 0x5 /* 488.281 us period */ #define MC_RATE_1024_Hz 0x6 /* 976.562 us period */ #define MC_RATE_512_Hz 0x7 /* 1.953125 ms period */ #define MC_RATE_256_Hz 0x8 /* 3.90625 ms period */ #define MC_RATE_128_Hz 0x9 /* 7.8125 ms period */ #define MC_RATE_64_Hz 0xa /* 15.625 ms period */ #define MC_RATE_32_Hz 0xb /* 31.25 ms period */ #define MC_RATE_16_Hz 0xc /* 62.5 ms period */ #define MC_RATE_8_Hz 0xd /* 125 ms period */ #define MC_RATE_4_Hz 0xe /* 250 ms period */ #define MC_RATE_2_Hz 0xf /* 500 ms period */ /* * Time base (divisor select) constants (Control register A) */ #define MC_BASE_4_MHz 0x00 /* 4 MHz crystal */ #define MC_BASE_1_MHz 0x10 /* 1 MHz crystal */ #define MC_BASE_32_KHz 0x20 /* 32 kHz crystal */ #define MC_BASE_NONE 0x60 /* actually, both of these reset */ #define MC_BASE_RESET 0x70 #ifndef USE_TODR_MCCLOCK /* * RTC register/NVRAM read and write functions -- machine-dependent. * Appropriately manipulate RTC registers to get/put data values. */ u_int mc146818_read(void *, u_int); void mc146818_write(void *, u_int, u_int); /* * A collection of TOD/Alarm registers. */ typedef u_int mc_todregs[MC_NTODREGS]; /* * Get all of the TOD/Alarm registers * Must be called at splhigh(), and with the RTC properly set up. */ #define MC146818_GETTOD(sc, regs) \ do { \ int i; \ \ /* update in progress; spin loop */ \ while (mc146818_read(sc, MC_REGA) & MC_REGA_UIP) \ ; \ \ /* read all of the tod/alarm regs */ \ for (i = 0; i < MC_NTODREGS; i++) \ (*regs)[i] = mc146818_read(sc, i); \ } while (0); /* * Set all of the TOD/Alarm registers * Must be called at splhigh(), and with the RTC properly set up. */ #define MC146818_PUTTOD(sc, regs) \ do { \ int i; \ \ /* stop updates while setting */ \ mc146818_write(sc, MC_REGB, \ mc146818_read(sc, MC_REGB) | MC_REGB_SET); \ \ /* write all of the tod/alarm regs */ \ for (i = 0; i < MC_NTODREGS; i++) \ mc146818_write(sc, i, (*regs)[i]); \ \ /* reenable updates */ \ mc146818_write(sc, MC_REGB, \ mc146818_read(sc, MC_REGB) & ~MC_REGB_SET); \ } while (0); #endif /* USE_TODR_MCCLOCK */