1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Machine dependent access functions for RTC registers.
7  *
8  * Copyright (C) 1996, 1997, 1998 Ralf Baechle
9  * Copyright (C) 2002  Maciej W. Rozycki
10  */
11 #ifndef _ASM_MC146818RTC_H
12 #define _ASM_MC146818RTC_H
13 
14 #include <linux/config.h>
15 
16 #include <asm/io.h>
17 
18 
19 /*
20  * This structure defines how to access various features of
21  * different machine types and how to access them.
22  */
23 struct rtc_ops {
24 	/* How to access the RTC register in a DS1287.  */
25 	unsigned char (*rtc_read_data)(unsigned long addr);
26 	void (*rtc_write_data)(unsigned char data, unsigned long addr);
27 	int (*rtc_bcd_mode)(void);
28 };
29 
30 extern struct rtc_ops *rtc_ops;
31 
32 /*
33  * Most supported machines access the RTC index register via an ISA
34  * port access but the way to access the date register differs ...
35  * The DECstation directly maps the RTC memory in the CPU's address
36  * space with the chipset generating necessary index write/data access
37  * cycles automagically.
38  */
39 #define CMOS_READ(addr) ({ \
40 rtc_ops->rtc_read_data(addr); \
41 })
42 #define CMOS_WRITE(val, addr) ({ \
43 rtc_ops->rtc_write_data(val, addr); \
44 })
45 #define RTC_ALWAYS_BCD \
46 rtc_ops->rtc_bcd_mode()
47 
48 
49 #ifdef CONFIG_DECSTATION
50 
51 #include <asm/dec/rtc-dec.h>
52 
53 #else
54 
55 #define RTC_PORT(x)	(0x70 + (x))
56 #define RTC_IRQ		8
57 
58 #endif
59 
60 #endif /* _ASM_MC146818RTC_H */
61