freebsd-dev/sys/mips/include/clock.h
Neel Natu 69a5a0bfea Sibyte provides a 64-bit read-only counter that counts at half the processor
frequency. This counter can be accessed coherently from both cores.

Use this as the preferred timecounter for the SWARM kernels.

The CP0 COUNT register is unusable as the timecounter on SMP platforms because
the COUNT registers on different CPUs are not guaranteed to be in sync.
2010-03-20 05:49:06 +00:00

48 lines
1.1 KiB
C

/*
* Garrett Wollman, September 1994.
* This file is in the public domain.
* Kernel interface to machine-dependent clock driver.
*
* JNPR: clock.h,v 1.6.2.1 2007/08/29 09:36:05 girish
* from: src/sys/alpha/include/clock.h,v 1.5 1999/12/29 04:27:55 peter
* $FreeBSD$
*/
#ifndef _MACHINE_CLOCK_H_
#define _MACHINE_CLOCK_H_
#include <sys/bus.h>
#ifdef _KERNEL
extern int cpu_clock;
extern uint32_t clockintr(uint32_t, struct clockframe *);
#define wall_cmos_clock 0
#define adjkerntz 0
/*
* Default is to assume a CPU pipeline clock of 100Mhz, and
* that CP0_COUNT increments every 2 cycles.
*/
#define MIPS_DEFAULT_HZ (100 * 1000 * 1000)
void mips_timer_early_init(uint64_t clock_hz);
void mips_timer_init_params(uint64_t, int);
extern uint64_t counter_freq;
extern int clocks_running;
/*
* The 'platform_timecounter' pointer may be used to register a
* platform-specific timecounter.
*
* A default timecounter based on the CP0 COUNT register is always registered.
*/
extern struct timecounter *platform_timecounter;
#endif
#endif /* !_MACHINE_CLOCK_H_ */