2 * (c) Copyright 2004 Benjamin Herrenschmidt (benh@kernel.crashing.org),
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version
8 * 2 of the License, or (at your option) any later version.
14 #include <linux/errno.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/param.h>
18 #include <linux/string.h>
20 #include <linux/init.h>
21 #include <linux/time.h>
22 #include <linux/adb.h>
23 #include <linux/pmu.h>
24 #include <linux/interrupt.h>
25 #include <linux/mc146818rtc.h>
26 #include <linux/bcd.h>
28 #include <asm/sections.h>
30 #include <asm/system.h>
32 #include <asm/pgtable.h>
33 #include <asm/machdep.h>
39 #define DBG(x...) printk(x)
44 static int maple_rtc_addr
;
46 static int maple_clock_read(int addr
)
48 outb_p(addr
, maple_rtc_addr
);
49 return inb_p(maple_rtc_addr
+1);
52 static void maple_clock_write(unsigned long val
, int addr
)
54 outb_p(addr
, maple_rtc_addr
);
55 outb_p(val
, maple_rtc_addr
+1);
58 void maple_get_rtc_time(struct rtc_time
*tm
)
61 tm
->tm_sec
= maple_clock_read(RTC_SECONDS
);
62 tm
->tm_min
= maple_clock_read(RTC_MINUTES
);
63 tm
->tm_hour
= maple_clock_read(RTC_HOURS
);
64 tm
->tm_mday
= maple_clock_read(RTC_DAY_OF_MONTH
);
65 tm
->tm_mon
= maple_clock_read(RTC_MONTH
);
66 tm
->tm_year
= maple_clock_read(RTC_YEAR
);
67 } while (tm
->tm_sec
!= maple_clock_read(RTC_SECONDS
));
69 if (!(maple_clock_read(RTC_CONTROL
) & RTC_DM_BINARY
)
71 tm
->tm_sec
= bcd2bin(tm
->tm_sec
);
72 tm
->tm_min
= bcd2bin(tm
->tm_min
);
73 tm
->tm_hour
= bcd2bin(tm
->tm_hour
);
74 tm
->tm_mday
= bcd2bin(tm
->tm_mday
);
75 tm
->tm_mon
= bcd2bin(tm
->tm_mon
);
76 tm
->tm_year
= bcd2bin(tm
->tm_year
);
78 if ((tm
->tm_year
+ 1900) < 1970)
84 int maple_set_rtc_time(struct rtc_time
*tm
)
86 unsigned char save_control
, save_freq_select
;
87 int sec
, min
, hour
, mon
, mday
, year
;
91 save_control
= maple_clock_read(RTC_CONTROL
); /* tell the clock it's being set */
93 maple_clock_write((save_control
|RTC_SET
), RTC_CONTROL
);
95 save_freq_select
= maple_clock_read(RTC_FREQ_SELECT
); /* stop and reset prescaler */
97 maple_clock_write((save_freq_select
|RTC_DIV_RESET2
), RTC_FREQ_SELECT
);
106 if (!(save_control
& RTC_DM_BINARY
) || RTC_ALWAYS_BCD
) {
109 hour
= bin2bcd(hour
);
111 mday
= bin2bcd(mday
);
112 year
= bin2bcd(year
);
114 maple_clock_write(sec
, RTC_SECONDS
);
115 maple_clock_write(min
, RTC_MINUTES
);
116 maple_clock_write(hour
, RTC_HOURS
);
117 maple_clock_write(mon
, RTC_MONTH
);
118 maple_clock_write(mday
, RTC_DAY_OF_MONTH
);
119 maple_clock_write(year
, RTC_YEAR
);
121 /* The following flags have to be released exactly in this order,
122 * otherwise the DS12887 (popular MC146818A clone with integrated
123 * battery and quartz) will not reset the oscillator and will not
124 * update precisely 500 ms later. You won't find this mentioned in
125 * the Dallas Semiconductor data sheets, but who believes data
126 * sheets anyway ... -- Markus Kuhn
128 maple_clock_write(save_control
, RTC_CONTROL
);
129 maple_clock_write(save_freq_select
, RTC_FREQ_SELECT
);
131 spin_unlock(&rtc_lock
);
136 static struct resource rtc_iores
= {
138 .flags
= IORESOURCE_BUSY
,
141 unsigned long __init
maple_get_boot_time(void)
144 struct device_node
*rtcs
;
146 rtcs
= of_find_compatible_node(NULL
, "rtc", "pnpPNP,b00");
149 if (of_address_to_resource(rtcs
, 0, &r
)) {
150 printk(KERN_EMERG
"Maple: Unable to translate RTC"
154 if (!(r
.flags
& IORESOURCE_IO
)) {
155 printk(KERN_EMERG
"Maple: RTC address isn't PIO!\n");
158 maple_rtc_addr
= r
.start
;
159 printk(KERN_INFO
"Maple: Found RTC at IO 0x%x\n",
163 if (maple_rtc_addr
== 0) {
164 maple_rtc_addr
= RTC_PORT(0); /* legacy address */
165 printk(KERN_INFO
"Maple: No device node for RTC, assuming "
166 "legacy address (0x%x)\n", maple_rtc_addr
);
169 rtc_iores
.start
= maple_rtc_addr
;
170 rtc_iores
.end
= maple_rtc_addr
+ 7;
171 request_resource(&ioport_resource
, &rtc_iores
);
173 maple_get_rtc_time(&tm
);
174 return mktime(tm
.tm_year
+1900, tm
.tm_mon
+1, tm
.tm_mday
,
175 tm
.tm_hour
, tm
.tm_min
, tm
.tm_sec
);