xref: /openbmc/linux/arch/sparc/include/asm/timer_32.h (revision 9cfc5c90)
1 /*
2  * timer.h:  Definitions for the timer chips on the Sparc.
3  *
4  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5  */
6 
7 
8 #ifndef _SPARC_TIMER_H
9 #define _SPARC_TIMER_H
10 
11 #include <linux/clocksource.h>
12 #include <linux/irqreturn.h>
13 
14 #include <asm-generic/percpu.h>
15 
16 #include <asm/cpu_type.h>  /* For SUN4M_NCPUS */
17 
18 #define SBUS_CLOCK_RATE   2000000 /* 2MHz */
19 #define TIMER_VALUE_SHIFT 9
20 #define TIMER_VALUE_MASK  0x3fffff
21 #define TIMER_LIMIT_BIT   (1 << 31)  /* Bit 31 in Counter-Timer register */
22 
23 /* The counter timer register has the value offset by 9 bits.
24  * From sun4m manual:
25  * When a counter reaches the value in the corresponding limit register,
26  * the Limit bit is set and the counter is set to 500 nS (i.e. 0x00000200).
27  *
28  * To compensate for this add one to the value.
29  */
30 static inline unsigned int timer_value(unsigned int value)
31 {
32 	return (value + 1) << TIMER_VALUE_SHIFT;
33 }
34 
35 extern volatile u32 __iomem *master_l10_counter;
36 
37 irqreturn_t notrace timer_interrupt(int dummy, void *dev_id);
38 
39 #ifdef CONFIG_SMP
40 DECLARE_PER_CPU(struct clock_event_device, sparc32_clockevent);
41 void register_percpu_ce(int cpu);
42 #endif
43 
44 #endif /* !(_SPARC_TIMER_H) */
45