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
SetRTC_Access(RTC_ACCESS a)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
rtc_get(struct rtc_time * tmp)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
rtc_set(struct rtc_time * tmp)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
rtc_reset(void)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