1 /* 2 * (C) Copyright 2001-2008 3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4 * Keith Outwater, keith_outwater@mvis.com` 5 * 6 * See file CREDITS for list of people who contributed to this 7 * project. 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License as 11 * published by the Free Software Foundation; either version 2 of 12 * the License, or (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 22 * MA 02111-1307 USA 23 */ 24 25 /* 26 * Date & Time support (no alarms) for Dallas Semiconductor (now Maxim) 27 * DS1337 Real Time Clock (RTC). 28 */ 29 30 #include <common.h> 31 #include <command.h> 32 #include <rtc.h> 33 #include <i2c.h> 34 35 #if defined(CONFIG_CMD_DATE) 36 37 /* 38 * RTC register addresses 39 */ 40 #if defined CONFIG_RTC_DS1337 41 #define RTC_SEC_REG_ADDR 0x0 42 #define RTC_MIN_REG_ADDR 0x1 43 #define RTC_HR_REG_ADDR 0x2 44 #define RTC_DAY_REG_ADDR 0x3 45 #define RTC_DATE_REG_ADDR 0x4 46 #define RTC_MON_REG_ADDR 0x5 47 #define RTC_YR_REG_ADDR 0x6 48 #define RTC_CTL_REG_ADDR 0x0e 49 #define RTC_STAT_REG_ADDR 0x0f 50 #define RTC_TC_REG_ADDR 0x10 51 #elif defined CONFIG_RTC_DS1388 52 #define RTC_SEC_REG_ADDR 0x1 53 #define RTC_MIN_REG_ADDR 0x2 54 #define RTC_HR_REG_ADDR 0x3 55 #define RTC_DAY_REG_ADDR 0x4 56 #define RTC_DATE_REG_ADDR 0x5 57 #define RTC_MON_REG_ADDR 0x6 58 #define RTC_YR_REG_ADDR 0x7 59 #define RTC_CTL_REG_ADDR 0x0c 60 #define RTC_STAT_REG_ADDR 0x0b 61 #define RTC_TC_REG_ADDR 0x0a 62 #endif 63 64 /* 65 * RTC control register bits 66 */ 67 #define RTC_CTL_BIT_A1IE 0x1 /* Alarm 1 interrupt enable */ 68 #define RTC_CTL_BIT_A2IE 0x2 /* Alarm 2 interrupt enable */ 69 #define RTC_CTL_BIT_INTCN 0x4 /* Interrupt control */ 70 #define RTC_CTL_BIT_RS1 0x8 /* Rate select 1 */ 71 #define RTC_CTL_BIT_RS2 0x10 /* Rate select 2 */ 72 #define RTC_CTL_BIT_DOSC 0x80 /* Disable Oscillator */ 73 74 /* 75 * RTC status register bits 76 */ 77 #define RTC_STAT_BIT_A1F 0x1 /* Alarm 1 flag */ 78 #define RTC_STAT_BIT_A2F 0x2 /* Alarm 2 flag */ 79 #define RTC_STAT_BIT_OSF 0x80 /* Oscillator stop flag */ 80 81 82 static uchar rtc_read (uchar reg); 83 static void rtc_write (uchar reg, uchar val); 84 85 /* 86 * Get the current time from the RTC 87 */ 88 int rtc_get (struct rtc_time *tmp) 89 { 90 int rel = 0; 91 uchar sec, min, hour, mday, wday, mon_cent, year, control, status; 92 93 control = rtc_read (RTC_CTL_REG_ADDR); 94 status = rtc_read (RTC_STAT_REG_ADDR); 95 sec = rtc_read (RTC_SEC_REG_ADDR); 96 min = rtc_read (RTC_MIN_REG_ADDR); 97 hour = rtc_read (RTC_HR_REG_ADDR); 98 wday = rtc_read (RTC_DAY_REG_ADDR); 99 mday = rtc_read (RTC_DATE_REG_ADDR); 100 mon_cent = rtc_read (RTC_MON_REG_ADDR); 101 year = rtc_read (RTC_YR_REG_ADDR); 102 103 /* No century bit, assume year 2000 */ 104 #ifdef CONFIG_RTC_DS1388 105 mon_cent |= 0x80; 106 #endif 107 108 debug("Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x " 109 "hr: %02x min: %02x sec: %02x control: %02x status: %02x\n", 110 year, mon_cent, mday, wday, hour, min, sec, control, status); 111 112 if (status & RTC_STAT_BIT_OSF) { 113 printf ("### Warning: RTC oscillator has stopped\n"); 114 /* clear the OSF flag */ 115 rtc_write (RTC_STAT_REG_ADDR, 116 rtc_read (RTC_STAT_REG_ADDR) & ~RTC_STAT_BIT_OSF); 117 rel = -1; 118 } 119 120 tmp->tm_sec = bcd2bin (sec & 0x7F); 121 tmp->tm_min = bcd2bin (min & 0x7F); 122 tmp->tm_hour = bcd2bin (hour & 0x3F); 123 tmp->tm_mday = bcd2bin (mday & 0x3F); 124 tmp->tm_mon = bcd2bin (mon_cent & 0x1F); 125 tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 2000 : 1900); 126 tmp->tm_wday = bcd2bin ((wday - 1) & 0x07); 127 tmp->tm_yday = 0; 128 tmp->tm_isdst= 0; 129 130 debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 131 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 132 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 133 134 return rel; 135 } 136 137 138 /* 139 * Set the RTC 140 */ 141 int rtc_set (struct rtc_time *tmp) 142 { 143 uchar century; 144 145 debug("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 146 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 147 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 148 149 rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100)); 150 151 century = (tmp->tm_year >= 2000) ? 0x80 : 0; 152 rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon) | century); 153 154 rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday + 1)); 155 rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday)); 156 rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour)); 157 rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min)); 158 rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec)); 159 160 return 0; 161 } 162 163 164 /* 165 * Reset the RTC. We also enable the oscillator output on the 166 * SQW/INTB* pin and program it for 32,768 Hz output. Note that 167 * according to the datasheet, turning on the square wave output 168 * increases the current drain on the backup battery from about 169 * 600 nA to 2uA. Define CONFIG_SYS_RTC_DS1337_NOOSC if you wish to turn 170 * off the OSC output. 171 */ 172 173 #ifdef CONFIG_SYS_RTC_DS1337_NOOSC 174 #define RTC_DS1337_RESET_VAL \ 175 (RTC_CTL_BIT_INTCN | RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS2) 176 #else 177 #define RTC_DS1337_RESET_VAL (RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS2) 178 #endif 179 void rtc_reset (void) 180 { 181 #ifdef CONFIG_SYS_RTC_DS1337 182 rtc_write (RTC_CTL_REG_ADDR, RTC_DS1337_RESET_VAL); 183 #elif defined CONFIG_SYS_RTC_DS1388 184 rtc_write(RTC_CTL_REG_ADDR, 0x0); /* hw default */ 185 #endif 186 #ifdef CONFIG_SYS_DS1339_TCR_VAL 187 rtc_write (RTC_TC_REG_ADDR, CONFIG_SYS_DS1339_TCR_VAL); 188 #endif 189 #ifdef CONFIG_SYS_DS1388_TCR_VAL 190 rtc_write(RTC_TC_REG_ADDR, CONFIG_SYS_DS1388_TCR_VAL); 191 #endif 192 } 193 194 195 /* 196 * Helper functions 197 */ 198 199 static 200 uchar rtc_read (uchar reg) 201 { 202 return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg)); 203 } 204 205 206 static void rtc_write (uchar reg, uchar val) 207 { 208 i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val); 209 } 210 211 #endif 212