78 строки
1.9 KiB
C
78 строки
1.9 KiB
C
/*
|
|
* linux/arch/m68k/hp300/time.c
|
|
*
|
|
* Copyright (C) 1998 Philip Blundell <philb@gnu.org>
|
|
*
|
|
* This file contains the HP300-specific time handling code.
|
|
*/
|
|
|
|
#include <asm/ptrace.h>
|
|
#include <linux/types.h>
|
|
#include <linux/init.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/interrupt.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/io.h>
|
|
#include <asm/system.h>
|
|
#include <asm/traps.h>
|
|
#include <asm/blinken.h>
|
|
|
|
/* Clock hardware definitions */
|
|
|
|
#define CLOCKBASE 0xf05f8000
|
|
|
|
#define CLKCR1 0x1
|
|
#define CLKCR2 0x3
|
|
#define CLKCR3 CLKCR1
|
|
#define CLKSR CLKCR2
|
|
#define CLKMSB1 0x5
|
|
#define CLKMSB2 0x9
|
|
#define CLKMSB3 0xD
|
|
|
|
/* This is for machines which generate the exact clock. */
|
|
#define USECS_PER_JIFFY (1000000/HZ)
|
|
|
|
#define INTVAL ((10000 / 4) - 1)
|
|
|
|
static irqreturn_t hp300_tick(int irq, void *dev_id)
|
|
{
|
|
unsigned long tmp;
|
|
irq_handler_t vector = dev_id;
|
|
in_8(CLOCKBASE + CLKSR);
|
|
asm volatile ("movpw %1@(5),%0" : "=d" (tmp) : "a" (CLOCKBASE));
|
|
/* Turn off the network and SCSI leds */
|
|
blinken_leds(0, 0xe0);
|
|
return vector(irq, NULL);
|
|
}
|
|
|
|
unsigned long hp300_gettimeoffset(void)
|
|
{
|
|
/* Read current timer 1 value */
|
|
unsigned char lsb, msb1, msb2;
|
|
unsigned short ticks;
|
|
|
|
msb1 = in_8(CLOCKBASE + 5);
|
|
lsb = in_8(CLOCKBASE + 7);
|
|
msb2 = in_8(CLOCKBASE + 5);
|
|
if (msb1 != msb2)
|
|
/* A carry happened while we were reading. Read it again */
|
|
lsb = in_8(CLOCKBASE + 7);
|
|
ticks = INTVAL - ((msb2 << 8) | lsb);
|
|
return (USECS_PER_JIFFY * ticks) / INTVAL;
|
|
}
|
|
|
|
void __init hp300_sched_init(irq_handler_t vector)
|
|
{
|
|
out_8(CLOCKBASE + CLKCR2, 0x1); /* select CR1 */
|
|
out_8(CLOCKBASE + CLKCR1, 0x1); /* reset */
|
|
|
|
asm volatile(" movpw %0,%1@(5)" : : "d" (INTVAL), "a" (CLOCKBASE));
|
|
|
|
request_irq(IRQ_AUTO_6, hp300_tick, IRQ_FLG_STD, "timer tick", vector);
|
|
|
|
out_8(CLOCKBASE + CLKCR2, 0x1); /* select CR1 */
|
|
out_8(CLOCKBASE + CLKCR1, 0x40); /* enable irq */
|
|
}
|