linux/arch/mn10300/unit-asb2305/include/unit/timex.h

147 lines
3.2 KiB
C

/* ASB2305-specific timer specifications
*
* Copyright (C) 2007, 2010 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#ifndef _ASM_UNIT_TIMEX_H
#define _ASM_UNIT_TIMEX_H
#include <asm/timer-regs.h>
#include <unit/clock.h>
#include <asm/param.h>
/*
* jiffies counter specifications
*/
#define TMJCBR_MAX 0xffff
#define TMJCIRQ TM1IRQ
#define TMJCICR TM1ICR
#ifndef __ASSEMBLY__
#define MN10300_SRC_IOCLK MN10300_IOCLK
#ifndef HZ
# error HZ undeclared.
#endif /* !HZ */
/* use as little prescaling as possible to avoid losing accuracy */
#if (MN10300_SRC_IOCLK + HZ / 2) / HZ - 1 <= TMJCBR_MAX
# define IOCLK_PRESCALE 1
# define JC_TIMER_CLKSRC TM0MD_SRC_IOCLK
# define TSC_TIMER_CLKSRC TM4MD_SRC_IOCLK
#elif (MN10300_SRC_IOCLK / 8 + HZ / 2) / HZ - 1 <= TMJCBR_MAX
# define IOCLK_PRESCALE 8
# define JC_TIMER_CLKSRC TM0MD_SRC_IOCLK_8
# define TSC_TIMER_CLKSRC TM4MD_SRC_IOCLK_8
#elif (MN10300_SRC_IOCLK / 32 + HZ / 2) / HZ - 1 <= TMJCBR_MAX
# define IOCLK_PRESCALE 32
# define JC_TIMER_CLKSRC TM0MD_SRC_IOCLK_32
# define TSC_TIMER_CLKSRC TM4MD_SRC_IOCLK_32
#else
# error You lose.
#endif
#define MN10300_JCCLK (MN10300_SRC_IOCLK / IOCLK_PRESCALE)
#define MN10300_TSCCLK (MN10300_SRC_IOCLK / IOCLK_PRESCALE)
#define MN10300_JC_PER_HZ ((MN10300_JCCLK + HZ / 2) / HZ)
#define MN10300_TSC_PER_HZ ((MN10300_TSCCLK + HZ / 2) / HZ)
static inline void stop_jiffies_counter(void)
{
u16 tmp;
TM01MD = JC_TIMER_CLKSRC | TM1MD_SRC_TM0CASCADE << 8;
tmp = TM01MD;
}
static inline void reload_jiffies_counter(u32 cnt)
{
u32 tmp;
TM01BR = cnt;
tmp = TM01BR;
TM01MD = JC_TIMER_CLKSRC | \
TM1MD_SRC_TM0CASCADE << 8 | \
TM0MD_INIT_COUNTER | \
TM1MD_INIT_COUNTER << 8;
TM01MD = JC_TIMER_CLKSRC | \
TM1MD_SRC_TM0CASCADE << 8 | \
TM0MD_COUNT_ENABLE | \
TM1MD_COUNT_ENABLE << 8;
tmp = TM01MD;
}
#endif /* !__ASSEMBLY__ */
/*
* timestamp counter specifications
*/
#define TMTSCBR_MAX 0xffffffff
#define TMTSCBC TM45BC
#ifndef __ASSEMBLY__
static inline void startup_timestamp_counter(void)
{
u32 t32;
/* set up timer 4 & 5 cascaded as a 32-bit counter to count real time
* - count down from 4Gig-1 to 0 and wrap at IOCLK rate
*/
TM45BR = TMTSCBR_MAX;
t32 = TM45BR;
TM4MD = TSC_TIMER_CLKSRC;
TM4MD |= TM4MD_INIT_COUNTER;
TM4MD &= ~TM4MD_INIT_COUNTER;
TM4ICR = 0;
t32 = TM4ICR;
TM5MD = TM5MD_SRC_TM4CASCADE;
TM5MD |= TM5MD_INIT_COUNTER;
TM5MD &= ~TM5MD_INIT_COUNTER;
TM5ICR = 0;
t32 = TM5ICR;
TM5MD |= TM5MD_COUNT_ENABLE;
TM4MD |= TM4MD_COUNT_ENABLE;
t32 = TM5MD;
t32 = TM4MD;
}
static inline void shutdown_timestamp_counter(void)
{
u8 t8;
TM4MD = 0;
TM5MD = 0;
t8 = TM4MD;
t8 = TM5MD;
}
/*
* we use a cascaded pair of 16-bit down-counting timers to count I/O
* clock cycles for the purposes of time keeping
*/
typedef unsigned long cycles_t;
static inline cycles_t read_timestamp_counter(void)
{
return (cycles_t)~TMTSCBC;
}
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_UNIT_TIMEX_H */