1 /* 2 * (C) Copyright 2001 3 * Denis Peter MPL AG Switzerland. d.peter@mpl.ch 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 /* 9 * Date & Time support for the MC146818 (PIXX4) RTC 10 */ 11 12 /*#define DEBUG*/ 13 14 #include <common.h> 15 #include <command.h> 16 #include <rtc.h> 17 18 #if defined(__I386__) || defined(CONFIG_MALTA) 19 #include <asm/io.h> 20 #define in8(p) inb(p) 21 #define out8(p, v) outb(v, p) 22 #endif 23 24 #if defined(CONFIG_CMD_DATE) 25 26 /* Set this to 1 to clear the CMOS RAM */ 27 #define CLEAR_CMOS 0 28 29 #define RTC_PORT_MC146818 CONFIG_SYS_ISA_IO_BASE_ADDRESS + 0x70 30 #define RTC_SECONDS 0x00 31 #define RTC_SECONDS_ALARM 0x01 32 #define RTC_MINUTES 0x02 33 #define RTC_MINUTES_ALARM 0x03 34 #define RTC_HOURS 0x04 35 #define RTC_HOURS_ALARM 0x05 36 #define RTC_DAY_OF_WEEK 0x06 37 #define RTC_DATE_OF_MONTH 0x07 38 #define RTC_MONTH 0x08 39 #define RTC_YEAR 0x09 40 #define RTC_CONFIG_A 0x0A 41 #define RTC_CONFIG_B 0x0B 42 #define RTC_CONFIG_C 0x0C 43 #define RTC_CONFIG_D 0x0D 44 #define RTC_REG_SIZE 0x80 45 46 #define RTC_CONFIG_A_REF_CLCK_32KHZ (1 << 5) 47 #define RTC_CONFIG_A_RATE_1024HZ 6 48 49 #define RTC_CONFIG_B_24H (1 << 1) 50 51 #define RTC_CONFIG_D_VALID_RAM_AND_TIME 0x80 52 53 /* ------------------------------------------------------------------------- */ 54 55 int rtc_get (struct rtc_time *tmp) 56 { 57 uchar sec, min, hour, mday, wday, mon, year; 58 /* here check if rtc can be accessed */ 59 while ((rtc_read8(RTC_CONFIG_A) & 0x80) == 0x80); 60 sec = rtc_read8(RTC_SECONDS); 61 min = rtc_read8(RTC_MINUTES); 62 hour = rtc_read8(RTC_HOURS); 63 mday = rtc_read8(RTC_DATE_OF_MONTH); 64 wday = rtc_read8(RTC_DAY_OF_WEEK); 65 mon = rtc_read8(RTC_MONTH); 66 year = rtc_read8(RTC_YEAR); 67 #ifdef RTC_DEBUG 68 printf ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x " 69 "hr: %02x min: %02x sec: %02x\n", 70 year, mon, mday, wday, 71 hour, min, sec ); 72 printf ( "Alarms: month: %02x hour: %02x min: %02x sec: %02x\n", 73 rtc_read8(RTC_CONFIG_D) & 0x3F, 74 rtc_read8(RTC_HOURS_ALARM), 75 rtc_read8(RTC_MINUTES_ALARM), 76 rtc_read8(RTC_SECONDS_ALARM)); 77 #endif 78 tmp->tm_sec = bcd2bin (sec & 0x7F); 79 tmp->tm_min = bcd2bin (min & 0x7F); 80 tmp->tm_hour = bcd2bin (hour & 0x3F); 81 tmp->tm_mday = bcd2bin (mday & 0x3F); 82 tmp->tm_mon = bcd2bin (mon & 0x1F); 83 tmp->tm_year = bcd2bin (year); 84 tmp->tm_wday = bcd2bin (wday & 0x07); 85 if(tmp->tm_year<70) 86 tmp->tm_year+=2000; 87 else 88 tmp->tm_year+=1900; 89 tmp->tm_yday = 0; 90 tmp->tm_isdst= 0; 91 #ifdef RTC_DEBUG 92 printf ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 93 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 94 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 95 #endif 96 97 return 0; 98 } 99 100 int rtc_set (struct rtc_time *tmp) 101 { 102 #ifdef RTC_DEBUG 103 printf ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 104 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 105 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 106 #endif 107 rtc_write8(RTC_CONFIG_B, 0x82); /* disable the RTC to update the regs */ 108 109 rtc_write8(RTC_YEAR, bin2bcd(tmp->tm_year % 100)); 110 rtc_write8(RTC_MONTH, bin2bcd(tmp->tm_mon)); 111 rtc_write8(RTC_DAY_OF_WEEK, bin2bcd(tmp->tm_wday)); 112 rtc_write8(RTC_DATE_OF_MONTH, bin2bcd(tmp->tm_mday)); 113 rtc_write8(RTC_HOURS, bin2bcd(tmp->tm_hour)); 114 rtc_write8(RTC_MINUTES, bin2bcd(tmp->tm_min)); 115 rtc_write8(RTC_SECONDS, bin2bcd(tmp->tm_sec)); 116 rtc_write8(RTC_CONFIG_B, 0x02); /* enable the RTC to update the regs */ 117 118 return 0; 119 } 120 121 void rtc_reset (void) 122 { 123 rtc_write8(RTC_CONFIG_B, 0x82); /* disable the RTC to update the regs */ 124 rtc_write8(RTC_CONFIG_A, 0x20); /* Normal OP */ 125 rtc_write8(RTC_CONFIG_B, 0x00); 126 rtc_write8(RTC_CONFIG_B, 0x00); 127 rtc_write8(RTC_CONFIG_B, 0x02); /* enable the RTC to update the regs */ 128 } 129 130 /* ------------------------------------------------------------------------- */ 131 132 /* 133 * use direct memory access 134 */ 135 int rtc_read8(int reg) 136 { 137 #ifdef CONFIG_SYS_RTC_REG_BASE_ADDR 138 return in8(CONFIG_SYS_RTC_REG_BASE_ADDR + reg); 139 #else 140 int ofs = 0; 141 142 if (reg >= 128) { 143 ofs = 2; 144 reg -= 128; 145 } 146 out8(RTC_PORT_MC146818 + ofs, reg); 147 148 return in8(RTC_PORT_MC146818 + ofs + 1); 149 #endif 150 } 151 152 void rtc_write8(int reg, uchar val) 153 { 154 #ifdef CONFIG_SYS_RTC_REG_BASE_ADDR 155 out8(CONFIG_SYS_RTC_REG_BASE_ADDR + reg, val); 156 #else 157 int ofs = 0; 158 159 if (reg >= 128) { 160 ofs = 2; 161 reg -= 128; 162 } 163 out8(RTC_PORT_MC146818 + ofs, reg); 164 out8(RTC_PORT_MC146818 + ofs + 1, val); 165 #endif 166 } 167 168 u32 rtc_read32(int reg) 169 { 170 u32 value = 0; 171 int i; 172 173 for (i = 0; i < sizeof(value); i++) 174 value |= rtc_read8(reg + i) << (i << 3); 175 176 return value; 177 } 178 179 void rtc_write32(int reg, u32 value) 180 { 181 int i; 182 183 for (i = 0; i < sizeof(value); i++) 184 rtc_write8(reg + i, (value >> (i << 3)) & 0xff); 185 } 186 187 void rtc_init(void) 188 { 189 #if CLEAR_CMOS 190 int i; 191 192 rtc_write8(RTC_SECONDS_ALARM, 0); 193 rtc_write8(RTC_MINUTES_ALARM, 0); 194 rtc_write8(RTC_HOURS_ALARM, 0); 195 for (i = RTC_CONFIG_A; i < RTC_REG_SIZE; i++) 196 rtc_write8(i, 0); 197 printf("RTC: zeroing CMOS RAM\n"); 198 #endif 199 200 /* Setup the real time clock */ 201 rtc_write8(RTC_CONFIG_B, RTC_CONFIG_B_24H); 202 /* Setup the frequency it operates at */ 203 rtc_write8(RTC_CONFIG_A, RTC_CONFIG_A_REF_CLCK_32KHZ | 204 RTC_CONFIG_A_RATE_1024HZ); 205 /* Ensure all reserved bits are 0 in register D */ 206 rtc_write8(RTC_CONFIG_D, RTC_CONFIG_D_VALID_RAM_AND_TIME); 207 208 /* Clear any pending interrupts */ 209 rtc_read8(RTC_CONFIG_C); 210 } 211 #endif 212