xref: /linux/arch/mips/include/asm/time.h (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
1 /*
2  * Copyright (C) 2001, 2002, MontaVista Software Inc.
3  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
4  * Copyright (c) 2003  Maciej W. Rozycki
5  *
6  * include/asm-mips/time.h
7  *     header file for the new style time.c file and time services.
8  *
9  * This program is free software; you can redistribute	it and/or modify it
10  * under  the terms of	the GNU General	 Public License as published by the
11  * Free Software Foundation;  either version 2 of the  License, or (at your
12  * option) any later version.
13  */
14 #ifndef _ASM_TIME_H
15 #define _ASM_TIME_H
16 
17 #include <linux/rtc.h>
18 #include <linux/spinlock.h>
19 #include <linux/clockchips.h>
20 #include <linux/clocksource.h>
21 
22 extern spinlock_t rtc_lock;
23 
24 /*
25  * board specific routines required by time_init().
26  */
27 extern void plat_time_init(void);
28 
29 /*
30  * mips_hpt_frequency - must be set if you intend to use an R4k-compatible
31  * counter as a timer interrupt source.
32  */
33 extern unsigned int mips_hpt_frequency;
34 
35 /*
36  * The performance counter IRQ on MIPS is a close relative to the timer IRQ
37  * so it lives here.
38  */
39 extern int (*perf_irq)(void);
40 extern int __weak get_c0_perfcount_int(void);
41 
42 /*
43  * Initialize the calling CPU's compare interrupt as clockevent device
44  */
45 extern unsigned int get_c0_compare_int(void);
46 extern int r4k_clockevent_init(void);
47 
48 static inline int mips_clockevent_init(void)
49 {
50 #ifdef CONFIG_CEVT_R4K
51 	return r4k_clockevent_init();
52 #else
53 	return -ENXIO;
54 #endif
55 }
56 
57 /*
58  * Initialize the count register as a clocksource
59  */
60 extern int init_r4k_clocksource(void);
61 
62 static inline int init_mips_clocksource(void)
63 {
64 #ifdef CONFIG_CSRC_R4K
65 	return init_r4k_clocksource();
66 #else
67 	return 0;
68 #endif
69 }
70 
71 static inline void clockevent_set_clock(struct clock_event_device *cd,
72 					unsigned int clock)
73 {
74 	clockevents_calc_mult_shift(cd, clock, 4);
75 }
76 
77 #endif /* _ASM_TIME_H */
78