1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2003 4 * David Müller ELSOFT AG Switzerland. d.mueller@elsoft.ch 5 */ 6 7 /* 8 * Date & Time support for the built-in Samsung S3C24X0 RTC 9 */ 10 11 #include <common.h> 12 #include <command.h> 13 14 #if (defined(CONFIG_CMD_DATE)) 15 16 #include <asm/arch/s3c24x0_cpu.h> 17 18 #include <rtc.h> 19 #include <asm/io.h> 20 #include <linux/compiler.h> 21 22 typedef enum { 23 RTC_ENABLE, 24 RTC_DISABLE 25 } RTC_ACCESS; 26 27 28 static inline void SetRTC_Access(RTC_ACCESS a) 29 { 30 struct s3c24x0_rtc *rtc = s3c24x0_get_base_rtc(); 31 32 switch (a) { 33 case RTC_ENABLE: 34 writeb(readb(&rtc->rtccon) | 0x01, &rtc->rtccon); 35 break; 36 37 case RTC_DISABLE: 38 writeb(readb(&rtc->rtccon) & ~0x01, &rtc->rtccon); 39 break; 40 } 41 } 42 43 /* ------------------------------------------------------------------------- */ 44 45 int rtc_get(struct rtc_time *tmp) 46 { 47 struct s3c24x0_rtc *rtc = s3c24x0_get_base_rtc(); 48 uchar sec, min, hour, mday, wday, mon, year; 49 __maybe_unused uchar a_sec, a_min, a_hour, a_date, 50 a_mon, a_year, a_armed; 51 52 /* enable access to RTC registers */ 53 SetRTC_Access(RTC_ENABLE); 54 55 /* read RTC registers */ 56 do { 57 sec = readb(&rtc->bcdsec); 58 min = readb(&rtc->bcdmin); 59 hour = readb(&rtc->bcdhour); 60 mday = readb(&rtc->bcddate); 61 wday = readb(&rtc->bcdday); 62 mon = readb(&rtc->bcdmon); 63 year = readb(&rtc->bcdyear); 64 } while (sec != readb(&rtc->bcdsec)); 65 66 /* read ALARM registers */ 67 a_sec = readb(&rtc->almsec); 68 a_min = readb(&rtc->almmin); 69 a_hour = readb(&rtc->almhour); 70 a_date = readb(&rtc->almdate); 71 a_mon = readb(&rtc->almmon); 72 a_year = readb(&rtc->almyear); 73 a_armed = readb(&rtc->rtcalm); 74 75 /* disable access to RTC registers */ 76 SetRTC_Access(RTC_DISABLE); 77 78 #ifdef RTC_DEBUG 79 printf("Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x " 80 "hr: %02x min: %02x sec: %02x\n", 81 year, mon, mday, wday, hour, min, sec); 82 printf("Alarms: %02x: year: %02x month: %02x date: %02x hour: " 83 "%02x min: %02x sec: %02x\n", 84 a_armed, a_year, a_mon, a_date, a_hour, a_min, a_sec); 85 #endif 86 87 tmp->tm_sec = bcd2bin(sec & 0x7F); 88 tmp->tm_min = bcd2bin(min & 0x7F); 89 tmp->tm_hour = bcd2bin(hour & 0x3F); 90 tmp->tm_mday = bcd2bin(mday & 0x3F); 91 tmp->tm_mon = bcd2bin(mon & 0x1F); 92 tmp->tm_year = bcd2bin(year); 93 tmp->tm_wday = bcd2bin(wday & 0x07); 94 if (tmp->tm_year < 70) 95 tmp->tm_year += 2000; 96 else 97 tmp->tm_year += 1900; 98 tmp->tm_yday = 0; 99 tmp->tm_isdst = 0; 100 #ifdef RTC_DEBUG 101 printf("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 102 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 103 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 104 #endif 105 106 return 0; 107 } 108 109 int rtc_set(struct rtc_time *tmp) 110 { 111 struct s3c24x0_rtc *rtc = s3c24x0_get_base_rtc(); 112 uchar sec, min, hour, mday, wday, mon, year; 113 114 #ifdef RTC_DEBUG 115 printf("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 116 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 117 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 118 #endif 119 year = bin2bcd(tmp->tm_year % 100); 120 mon = bin2bcd(tmp->tm_mon); 121 wday = bin2bcd(tmp->tm_wday); 122 mday = bin2bcd(tmp->tm_mday); 123 hour = bin2bcd(tmp->tm_hour); 124 min = bin2bcd(tmp->tm_min); 125 sec = bin2bcd(tmp->tm_sec); 126 127 /* enable access to RTC registers */ 128 SetRTC_Access(RTC_ENABLE); 129 130 /* write RTC registers */ 131 writeb(sec, &rtc->bcdsec); 132 writeb(min, &rtc->bcdmin); 133 writeb(hour, &rtc->bcdhour); 134 writeb(mday, &rtc->bcddate); 135 writeb(wday, &rtc->bcdday); 136 writeb(mon, &rtc->bcdmon); 137 writeb(year, &rtc->bcdyear); 138 139 /* disable access to RTC registers */ 140 SetRTC_Access(RTC_DISABLE); 141 142 return 0; 143 } 144 145 void rtc_reset(void) 146 { 147 struct s3c24x0_rtc *rtc = s3c24x0_get_base_rtc(); 148 149 writeb((readb(&rtc->rtccon) & ~0x06) | 0x08, &rtc->rtccon); 150 writeb(readb(&rtc->rtccon) & ~(0x08 | 0x01), &rtc->rtccon); 151 } 152 153 #endif 154