xref: /openbmc/u-boot/drivers/rtc/ftrtc010.c (revision 419adbfb)
1 /*
2  * Faraday FTRTC010 Real Time Clock
3  *
4  * (C) Copyright 2009 Faraday Technology
5  * Po-Yu Chuang <ratbert@faraday-tech.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 #include <config.h>
23 #include <common.h>
24 #include <rtc.h>
25 #include <asm/io.h>
26 
27 struct ftrtc010 {
28 	unsigned int sec;		/* 0x00 */
29 	unsigned int min;		/* 0x04 */
30 	unsigned int hour;		/* 0x08 */
31 	unsigned int day;		/* 0x0c */
32 	unsigned int alarm_sec;		/* 0x10 */
33 	unsigned int alarm_min;		/* 0x14 */
34 	unsigned int alarm_hour;	/* 0x18 */
35 	unsigned int record;		/* 0x1c */
36 	unsigned int cr;		/* 0x20 */
37 	unsigned int wsec;		/* 0x24 */
38 	unsigned int wmin;		/* 0x28 */
39 	unsigned int whour;		/* 0x2c */
40 	unsigned int wday;		/* 0x30 */
41 	unsigned int intr;		/* 0x34 */
42 	unsigned int div;		/* 0x38 */
43 	unsigned int rev;		/* 0x3c */
44 };
45 
46 /*
47  * RTC Control Register
48  */
49 #define FTRTC010_CR_ENABLE		(1 << 0)
50 #define FTRTC010_CR_INTERRUPT_SEC	(1 << 1)	/* per second irq */
51 #define FTRTC010_CR_INTERRUPT_MIN	(1 << 2)	/* per minute irq */
52 #define FTRTC010_CR_INTERRUPT_HR	(1 << 3)	/* per hour   irq */
53 #define FTRTC010_CR_INTERRUPT_DAY	(1 << 4)	/* per day    irq */
54 
55 static struct ftrtc010 *rtc = (struct ftrtc010 *)CONFIG_FTRTC010_BASE;
56 
57 static void ftrtc010_enable(void)
58 {
59 	writel(FTRTC010_CR_ENABLE, &rtc->cr);
60 }
61 
62 /*
63  * return current time in seconds
64  */
65 static unsigned long ftrtc010_time(void)
66 {
67 	unsigned long day;
68 	unsigned long hour;
69 	unsigned long minute;
70 	unsigned long second;
71 	unsigned long second2;
72 
73 	do {
74 		second	= readl(&rtc->sec);
75 		day	= readl(&rtc->day);
76 		hour	= readl(&rtc->hour);
77 		minute	= readl(&rtc->min);
78 		second2	= readl(&rtc->sec);
79 	} while (second != second2);
80 
81 	return day * 24 * 60 * 60 + hour * 60 * 60 + minute * 60 + second;
82 }
83 
84 /*
85  * Get the current time from the RTC
86  */
87 
88 int rtc_get(struct rtc_time *tmp)
89 {
90 	unsigned long now;
91 
92 	debug("%s(): record register: %x\n",
93 	      __func__, readl(&rtc->record));
94 
95 #ifdef CONFIG_FTRTC010_PCLK
96 	now = (ftrtc010_time() + readl(&rtc->record)) / RTC_DIV_COUNT;
97 #else /* CONFIG_FTRTC010_EXTCLK */
98 	now = ftrtc010_time() + readl(&rtc->record);
99 #endif
100 
101 	to_tm(now, tmp);
102 
103 	return 0;
104 }
105 
106 /*
107  * Set the RTC
108  */
109 int rtc_set(struct rtc_time *tmp)
110 {
111 	unsigned long new;
112 	unsigned long now;
113 
114 	debug("%s(): DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
115 	      __func__,
116 	      tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
117 	      tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
118 
119 	new = mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_hour,
120 		     tmp->tm_min, tmp->tm_sec);
121 
122 	now = ftrtc010_time();
123 
124 	debug("%s(): write %lx to record register\n", __func__, new - now);
125 
126 	writel(new - now, &rtc->record);
127 
128 	return 0;
129 }
130 
131 void rtc_reset(void)
132 {
133 	debug("%s()\n", __func__);
134 	ftrtc010_enable();
135 }
136