xref: /openbmc/u-boot/drivers/rtc/ftrtc010.c (revision a3f3897b)
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 };
38 
39 /*
40  * RTC Control Register
41  */
42 #define FTRTC010_CR_ENABLE		(1 << 0)
43 #define FTRTC010_CR_INTERRUPT_SEC	(1 << 1)	/* per second irq */
44 #define FTRTC010_CR_INTERRUPT_MIN	(1 << 2)	/* per minute irq */
45 #define FTRTC010_CR_INTERRUPT_HR	(1 << 3)	/* per hour   irq */
46 #define FTRTC010_CR_INTERRUPT_DAY	(1 << 4)	/* per day    irq */
47 
48 static struct ftrtc010 *rtc = (struct ftrtc010 *)CONFIG_FTRTC010_BASE;
49 
50 static void ftrtc010_enable(void)
51 {
52 	writel(FTRTC010_CR_ENABLE, &rtc->cr);
53 }
54 
55 /*
56  * return current time in seconds
57  */
58 static unsigned long ftrtc010_time(void)
59 {
60 	unsigned long day;
61 	unsigned long hour;
62 	unsigned long minute;
63 	unsigned long second;
64 	unsigned long second2;
65 
66 	do {
67 		second	= readl(&rtc->sec);
68 		day	= readl(&rtc->day);
69 		hour	= readl(&rtc->hour);
70 		minute	= readl(&rtc->min);
71 		second2	= readl(&rtc->sec);
72 	} while (second != second2);
73 
74 	return day * 24 * 60 * 60 + hour * 60 * 60 + minute * 60 + second;
75 }
76 
77 /*
78  * Get the current time from the RTC
79  */
80 
81 int rtc_get(struct rtc_time *tmp)
82 {
83 	unsigned long now;
84 
85 	debug("%s(): record register: %x\n",
86 	      __func__, readl(&rtc->record));
87 
88 	now = ftrtc010_time() + readl(&rtc->record);
89 
90 	to_tm(now, tmp);
91 
92 	return 0;
93 }
94 
95 /*
96  * Set the RTC
97  */
98 int rtc_set(struct rtc_time *tmp)
99 {
100 	unsigned long new;
101 	unsigned long now;
102 
103 	debug("%s(): DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
104 	      __func__,
105 	      tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
106 	      tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
107 
108 	new = mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_hour,
109 		     tmp->tm_min, tmp->tm_sec);
110 
111 	now = ftrtc010_time();
112 
113 	debug("%s(): write %lx to record register\n", __func__, new - now);
114 
115 	writel(new - now, &rtc->record);
116 
117 	return 0;
118 }
119 
120 void rtc_reset(void)
121 {
122 	debug("%s()\n", __func__);
123 	ftrtc010_enable();
124 }
125