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