1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2001-2008 4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 5 * Keith Outwater, keith_outwater@mvis.com` 6 */ 7 8 /* 9 * Date & Time support (no alarms) for Dallas Semiconductor (now Maxim) 10 * DS1337 Real Time Clock (RTC). 11 */ 12 13 #include <common.h> 14 #include <command.h> 15 #include <rtc.h> 16 #include <i2c.h> 17 18 #if defined(CONFIG_CMD_DATE) 19 20 /* 21 * RTC register addresses 22 */ 23 #if defined CONFIG_RTC_DS1337 24 #define RTC_SEC_REG_ADDR 0x0 25 #define RTC_MIN_REG_ADDR 0x1 26 #define RTC_HR_REG_ADDR 0x2 27 #define RTC_DAY_REG_ADDR 0x3 28 #define RTC_DATE_REG_ADDR 0x4 29 #define RTC_MON_REG_ADDR 0x5 30 #define RTC_YR_REG_ADDR 0x6 31 #define RTC_CTL_REG_ADDR 0x0e 32 #define RTC_STAT_REG_ADDR 0x0f 33 #define RTC_TC_REG_ADDR 0x10 34 #elif defined CONFIG_RTC_DS1388 35 #define RTC_SEC_REG_ADDR 0x1 36 #define RTC_MIN_REG_ADDR 0x2 37 #define RTC_HR_REG_ADDR 0x3 38 #define RTC_DAY_REG_ADDR 0x4 39 #define RTC_DATE_REG_ADDR 0x5 40 #define RTC_MON_REG_ADDR 0x6 41 #define RTC_YR_REG_ADDR 0x7 42 #define RTC_CTL_REG_ADDR 0x0c 43 #define RTC_STAT_REG_ADDR 0x0b 44 #define RTC_TC_REG_ADDR 0x0a 45 #endif 46 47 /* 48 * RTC control register bits 49 */ 50 #define RTC_CTL_BIT_A1IE 0x1 /* Alarm 1 interrupt enable */ 51 #define RTC_CTL_BIT_A2IE 0x2 /* Alarm 2 interrupt enable */ 52 #define RTC_CTL_BIT_INTCN 0x4 /* Interrupt control */ 53 #define RTC_CTL_BIT_RS1 0x8 /* Rate select 1 */ 54 #define RTC_CTL_BIT_RS2 0x10 /* Rate select 2 */ 55 #define RTC_CTL_BIT_DOSC 0x80 /* Disable Oscillator */ 56 57 /* 58 * RTC status register bits 59 */ 60 #define RTC_STAT_BIT_A1F 0x1 /* Alarm 1 flag */ 61 #define RTC_STAT_BIT_A2F 0x2 /* Alarm 2 flag */ 62 #define RTC_STAT_BIT_OSF 0x80 /* Oscillator stop flag */ 63 64 65 static uchar rtc_read (uchar reg); 66 static void rtc_write (uchar reg, uchar val); 67 68 /* 69 * Get the current time from the RTC 70 */ 71 int rtc_get (struct rtc_time *tmp) 72 { 73 int rel = 0; 74 uchar sec, min, hour, mday, wday, mon_cent, year, control, status; 75 76 control = rtc_read (RTC_CTL_REG_ADDR); 77 status = rtc_read (RTC_STAT_REG_ADDR); 78 sec = rtc_read (RTC_SEC_REG_ADDR); 79 min = rtc_read (RTC_MIN_REG_ADDR); 80 hour = rtc_read (RTC_HR_REG_ADDR); 81 wday = rtc_read (RTC_DAY_REG_ADDR); 82 mday = rtc_read (RTC_DATE_REG_ADDR); 83 mon_cent = rtc_read (RTC_MON_REG_ADDR); 84 year = rtc_read (RTC_YR_REG_ADDR); 85 86 /* No century bit, assume year 2000 */ 87 #ifdef CONFIG_RTC_DS1388 88 mon_cent |= 0x80; 89 #endif 90 91 debug("Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x " 92 "hr: %02x min: %02x sec: %02x control: %02x status: %02x\n", 93 year, mon_cent, mday, wday, hour, min, sec, control, status); 94 95 if (status & RTC_STAT_BIT_OSF) { 96 printf ("### Warning: RTC oscillator has stopped\n"); 97 /* clear the OSF flag */ 98 rtc_write (RTC_STAT_REG_ADDR, 99 rtc_read (RTC_STAT_REG_ADDR) & ~RTC_STAT_BIT_OSF); 100 rel = -1; 101 } 102 103 tmp->tm_sec = bcd2bin (sec & 0x7F); 104 tmp->tm_min = bcd2bin (min & 0x7F); 105 tmp->tm_hour = bcd2bin (hour & 0x3F); 106 tmp->tm_mday = bcd2bin (mday & 0x3F); 107 tmp->tm_mon = bcd2bin (mon_cent & 0x1F); 108 tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 2000 : 1900); 109 tmp->tm_wday = bcd2bin ((wday - 1) & 0x07); 110 tmp->tm_yday = 0; 111 tmp->tm_isdst= 0; 112 113 debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 114 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 115 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 116 117 return rel; 118 } 119 120 121 /* 122 * Set the RTC 123 */ 124 int rtc_set (struct rtc_time *tmp) 125 { 126 uchar century; 127 128 debug("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 129 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 130 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 131 132 rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100)); 133 134 century = (tmp->tm_year >= 2000) ? 0x80 : 0; 135 rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon) | century); 136 137 rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday + 1)); 138 rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday)); 139 rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour)); 140 rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min)); 141 rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec)); 142 143 return 0; 144 } 145 146 147 /* 148 * Reset the RTC. We also enable the oscillator output on the 149 * SQW/INTB* pin and program it for 32,768 Hz output. Note that 150 * according to the datasheet, turning on the square wave output 151 * increases the current drain on the backup battery from about 152 * 600 nA to 2uA. Define CONFIG_RTC_DS1337_NOOSC if you wish to turn 153 * off the OSC output. 154 */ 155 156 #ifdef CONFIG_RTC_DS1337_NOOSC 157 #define RTC_DS1337_RESET_VAL \ 158 (RTC_CTL_BIT_INTCN | RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS2) 159 #else 160 #define RTC_DS1337_RESET_VAL (RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS2) 161 #endif 162 void rtc_reset (void) 163 { 164 #ifdef CONFIG_RTC_DS1337 165 rtc_write (RTC_CTL_REG_ADDR, RTC_DS1337_RESET_VAL); 166 #elif defined CONFIG_RTC_DS1388 167 rtc_write(RTC_CTL_REG_ADDR, 0x0); /* hw default */ 168 #endif 169 #ifdef CONFIG_RTC_DS1339_TCR_VAL 170 rtc_write (RTC_TC_REG_ADDR, CONFIG_RTC_DS1339_TCR_VAL); 171 #endif 172 #ifdef CONFIG_RTC_DS1388_TCR_VAL 173 rtc_write(RTC_TC_REG_ADDR, CONFIG_RTC_DS1388_TCR_VAL); 174 #endif 175 } 176 177 178 /* 179 * Helper functions 180 */ 181 182 static 183 uchar rtc_read (uchar reg) 184 { 185 return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg)); 186 } 187 188 189 static void rtc_write (uchar reg, uchar val) 190 { 191 i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val); 192 } 193 194 #endif 195