xref: /openbmc/u-boot/drivers/rtc/s3c24x0_rtc.c (revision c29d2d36)
1 /*
2  * (C) Copyright 2003
3  * David M�ller ELSOFT AG Switzerland. d.mueller@elsoft.ch
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 /*
25  * Date & Time support for the built-in Samsung S3C24X0 RTC
26  */
27 
28 #include <common.h>
29 #include <command.h>
30 
31 #if defined(CONFIG_RTC_S3C24X0) && (defined(CONFIG_CMD_DATE))
32 
33 #if defined(CONFIG_S3C2400)
34 #include <s3c2400.h>
35 #elif defined(CONFIG_S3C2410)
36 #include <s3c2410.h>
37 #endif
38 
39 #include <rtc.h>
40 
41 /*#define	DEBUG*/
42 
43 typedef enum {
44 	RTC_ENABLE,
45 	RTC_DISABLE
46 } RTC_ACCESS;
47 
48 
49 static inline void SetRTC_Access(RTC_ACCESS a)
50 {
51 	S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
52 	switch (a) {
53 		case RTC_ENABLE:
54 			rtc->RTCCON |= 0x01; break;
55 
56 		case RTC_DISABLE:
57 			rtc->RTCCON &= ~0x01; break;
58 	}
59 }
60 
61 static unsigned bcd2bin (uchar n)
62 {
63 	return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
64 }
65 
66 static unsigned char bin2bcd (unsigned int n)
67 {
68 	return (((n / 10) << 4) | (n % 10));
69 }
70 
71 /* ------------------------------------------------------------------------- */
72 
73 void rtc_get (struct rtc_time *tmp)
74 {
75 	S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
76 	uchar sec, min, hour, mday, wday, mon, year;
77 	uchar a_sec,a_min, a_hour, a_date, a_mon, a_year, a_armed;
78 
79 	/* enable access to RTC registers */
80 	SetRTC_Access(RTC_ENABLE);
81 
82 	/* read RTC registers */
83 	do {
84 		sec	= rtc->BCDSEC;
85 		min	= rtc->BCDMIN;
86 		hour	= rtc->BCDHOUR;
87 		mday	= rtc->BCDDATE;
88 		wday	= rtc->BCDDAY;
89 		mon	= rtc->BCDMON;
90 		year	= rtc->BCDYEAR;
91 	} while (sec != rtc->BCDSEC);
92 
93 	/* read ALARM registers */
94 	a_sec	= rtc->ALMSEC;
95 	a_min	= rtc->ALMMIN;
96 	a_hour	= rtc->ALMHOUR;
97 	a_date	= rtc->ALMDATE;
98 	a_mon	= rtc->ALMMON;
99 	a_year	= rtc->ALMYEAR;
100 	a_armed	= rtc->RTCALM;
101 
102 	/* disable access to RTC registers */
103 	SetRTC_Access(RTC_DISABLE);
104 
105 #ifdef RTC_DEBUG
106 	printf ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
107 		"hr: %02x min: %02x sec: %02x\n",
108 		year, mon, mday, wday,
109 		hour, min, sec);
110 	printf ( "Alarms: %02x: year: %02x month: %02x date: %02x hour: %02x min: %02x sec: %02x\n",
111 		a_armed,
112 		a_year, a_mon, a_date,
113 		a_hour, a_min, a_sec);
114 #endif
115 
116 	tmp->tm_sec  = bcd2bin(sec  & 0x7F);
117 	tmp->tm_min  = bcd2bin(min  & 0x7F);
118 	tmp->tm_hour = bcd2bin(hour & 0x3F);
119 	tmp->tm_mday = bcd2bin(mday & 0x3F);
120 	tmp->tm_mon  = bcd2bin(mon & 0x1F);
121 	tmp->tm_year = bcd2bin(year);
122 	tmp->tm_wday = bcd2bin(wday & 0x07);
123 	if(tmp->tm_year<70)
124 		tmp->tm_year+=2000;
125 	else
126 		tmp->tm_year+=1900;
127 	tmp->tm_yday = 0;
128 	tmp->tm_isdst= 0;
129 #ifdef RTC_DEBUG
130 	printf ( "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 #endif
134 }
135 
136 void rtc_set (struct rtc_time *tmp)
137 {
138 	S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
139 	uchar sec, min, hour, mday, wday, mon, year;
140 
141 #ifdef RTC_DEBUG
142 	printf ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
143 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
144 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
145 #endif
146 	year	= bin2bcd(tmp->tm_year % 100);
147 	mon	= bin2bcd(tmp->tm_mon);
148 	wday	= bin2bcd(tmp->tm_wday);
149 	mday	= bin2bcd(tmp->tm_mday);
150 	hour	= bin2bcd(tmp->tm_hour);
151 	min	= bin2bcd(tmp->tm_min);
152 	sec	= bin2bcd(tmp->tm_sec);
153 
154 	/* enable access to RTC registers */
155 	SetRTC_Access(RTC_ENABLE);
156 
157 	/* write RTC registers */
158 	rtc->BCDSEC	= sec;
159 	rtc->BCDMIN	= min;
160 	rtc->BCDHOUR	= hour;
161 	rtc->BCDDATE	= mday;
162 	rtc->BCDDAY	= wday;
163 	rtc->BCDMON	= mon;
164 	rtc->BCDYEAR	= year;
165 
166 	/* disable access to RTC registers */
167 	SetRTC_Access(RTC_DISABLE);
168 }
169 
170 void rtc_reset (void)
171 {
172 	S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
173 
174 	rtc->RTCCON = (rtc->RTCCON & ~0x06) | 0x08;
175 	rtc->RTCCON &= ~(0x08|0x01);
176 }
177 
178 #endif
179