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

136 lines
2.6 KiB
C

/* ASB2305 timer specifcations
*
* Copyright (C) 2007 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
#ifndef __ASSEMBLY__
#include <linux/irq.h>
#endif /* __ASSEMBLY__ */
#include <asm/timer-regs.h>
#include <unit/clock.h>
/*
* jiffies counter specifications
*/
#define TMJCBR_MAX 0xffff
#define TMJCBC TM01BC
#define TMJCMD TM01MD
#define TMJCBR TM01BR
#define TMJCIRQ TM1IRQ
#define TMJCICR TM1ICR
#define TMJCICR_LEVEL GxICR_LEVEL_5
#ifndef __ASSEMBLY__
static inline void startup_jiffies_counter(void)
{
unsigned rate;
u16 md, t16;
/* use as little prescaling as possible to avoid losing accuracy */
md = TM0MD_SRC_IOCLK;
rate = MN10300_JCCLK / HZ;
if (rate > TMJCBR_MAX) {
md = TM0MD_SRC_IOCLK_8;
rate = MN10300_JCCLK / 8 / HZ;
if (rate > TMJCBR_MAX) {
md = TM0MD_SRC_IOCLK_32;
rate = MN10300_JCCLK / 32 / HZ;
if (rate > TMJCBR_MAX)
BUG();
}
}
TMJCBR = rate - 1;
t16 = TMJCBR;
TMJCMD =
md |
TM1MD_SRC_TM0CASCADE << 8 |
TM0MD_INIT_COUNTER |
TM1MD_INIT_COUNTER << 8;
TMJCMD =
md |
TM1MD_SRC_TM0CASCADE << 8 |
TM0MD_COUNT_ENABLE |
TM1MD_COUNT_ENABLE << 8;
t16 = TMJCMD;
TMJCICR |= GxICR_ENABLE | GxICR_DETECT | GxICR_REQUEST;
t16 = TMJCICR;
}
static inline void shutdown_jiffies_counter(void)
{
}
#endif /* !__ASSEMBLY__ */
/*
* timestamp counter specifications
*/
#define TMTSCBR_MAX 0xffffffff
#define TMTSCBC TM45BC
#ifndef __ASSEMBLY__
static inline void startup_timestamp_counter(void)
{
/* 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;
TM4MD = TM4MD_SRC_IOCLK;
TM4MD |= TM4MD_INIT_COUNTER;
TM4MD &= ~TM4MD_INIT_COUNTER;
TM4ICR = 0;
TM5MD = TM5MD_SRC_TM4CASCADE;
TM5MD |= TM5MD_INIT_COUNTER;
TM5MD &= ~TM5MD_INIT_COUNTER;
TM5ICR = 0;
TM5MD |= TM5MD_COUNT_ENABLE;
TM4MD |= TM4MD_COUNT_ENABLE;
}
static inline void shutdown_timestamp_counter(void)
{
TM4MD = 0;
TM5MD = 0;
}
/*
* 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 */