kernel-ark/include/asm-xtensa/timex.h
Chris Zankel de6b03456e [XTENSA] Add volatile keyword to asm statements accessing counter registers
The compiler get's sometimes to smart and doesn't reread the
counter registers and the kernel doesn't schedule until the
counter wraps around.

Signed-off-by: Chris Zankel <chris@zankel.net>
2008-02-13 17:24:47 -08:00

97 lines
2.4 KiB
C

/*
* include/asm-xtensa/timex.h
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*/
#ifndef _XTENSA_TIMEX_H
#define _XTENSA_TIMEX_H
#ifdef __KERNEL__
#include <asm/processor.h>
#include <linux/stringify.h>
#define _INTLEVEL(x) XCHAL_INT ## x ## _LEVEL
#define INTLEVEL(x) _INTLEVEL(x)
#if INTLEVEL(XCHAL_TIMER0_INTERRUPT) == 1
# define LINUX_TIMER 0
# define LINUX_TIMER_INT XCHAL_TIMER0_INTERRUPT
#elif INTLEVEL(XCHAL_TIMER1_INTERRUPT) == 1
# define LINUX_TIMER 1
# define LINUX_TIMER_INT XCHAL_TIMER1_INTERRUPT
#elif INTLEVEL(XCHAL_TIMER2_INTERRUPT) == 1
# define LINUX_TIMER 2
# define LINUX_TIMER_INT XCHAL_TIMER2_INTERRUPT
#else
# error "Bad timer number for Linux configurations!"
#endif
#define LINUX_TIMER_MASK (1L << LINUX_TIMER_INT)
#define CLOCK_TICK_RATE 1193180 /* (everyone is using this value) */
#define CLOCK_TICK_FACTOR 20 /* Factor of both 10^6 and CLOCK_TICK_RATE */
#ifdef CONFIG_XTENSA_CALIBRATE_CCOUNT
extern unsigned long ccount_per_jiffy;
extern unsigned long ccount_nsec;
#define CCOUNT_PER_JIFFY ccount_per_jiffy
#define NSEC_PER_CCOUNT ccount_nsec
#else
#define CCOUNT_PER_JIFFY (CONFIG_XTENSA_CPU_CLOCK*(1000000UL/HZ))
#define NSEC_PER_CCOUNT (1000UL / CONFIG_XTENSA_CPU_CLOCK)
#endif
typedef unsigned long long cycles_t;
/*
* Only used for SMP.
*/
extern cycles_t cacheflush_time;
#define get_cycles() (0)
/*
* Register access.
*/
#define WSR_CCOUNT(r) asm volatile ("wsr %0,"__stringify(CCOUNT) :: "a" (r))
#define RSR_CCOUNT(r) asm volatile ("rsr %0,"__stringify(CCOUNT) : "=a" (r))
#define WSR_CCOMPARE(x,r) asm volatile ("wsr %0,"__stringify(CCOMPARE)"+"__stringify(x) :: "a"(r))
#define RSR_CCOMPARE(x,r) asm volatile ("rsr %0,"__stringify(CCOMPARE)"+"__stringify(x) : "=a"(r))
static inline unsigned long get_ccount (void)
{
unsigned long ccount;
RSR_CCOUNT(ccount);
return ccount;
}
static inline void set_ccount (unsigned long ccount)
{
WSR_CCOUNT(ccount);
}
static inline unsigned long get_linux_timer (void)
{
unsigned ccompare;
RSR_CCOMPARE(LINUX_TIMER, ccompare);
return ccompare;
}
static inline void set_linux_timer (unsigned long ccompare)
{
WSR_CCOMPARE(LINUX_TIMER, ccompare);
}
#endif /* __KERNEL__ */
#endif /* _XTENSA_TIMEX_H */