2 * timer.h: Definitions for the timer chips on the Sparc.
4 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
11 #include <linux/clocksource.h>
12 #include <linux/irqreturn.h>
14 #include <asm-generic/percpu.h>
16 #include <asm/cpu_type.h> /* For SUN4M_NCPUS */
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 */
23 /* The counter timer register has the value offset by 9 bits.
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).
28 * To compensate for this add one to the value.
30 static inline unsigned int timer_value(unsigned int value
)
32 return (value
+ 1) << TIMER_VALUE_SHIFT
;
35 extern volatile u32 __iomem
*master_l10_counter
;
37 irqreturn_t notrace
timer_interrupt(int dummy
, void *dev_id
);
40 DECLARE_PER_CPU(struct clock_event_device
, sparc32_clockevent
);
41 void register_percpu_ce(int cpu
);
44 #endif /* !(_SPARC_TIMER_H) */