mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
52 lines
1.4 KiB
C
52 lines
1.4 KiB
C
/*
|
|
* time.c: MIPS CPU Count/Compare timer hookup
|
|
*
|
|
* Author: Mark.Zhan, <rongkai.zhan@windriver.com>
|
|
*
|
|
* 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) 1996, 1997, 2004 by Ralf Baechle (ralf@linux-mips.org)
|
|
* Copyright (C) 2006, Wind River System Inc.
|
|
*/
|
|
#include <linux/init.h>
|
|
#include <linux/string.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/param.h> /* for HZ */
|
|
#include <linux/irq.h>
|
|
#include <linux/timex.h>
|
|
#include <linux/interrupt.h>
|
|
|
|
#include <asm/reboot.h>
|
|
#include <asm/time.h>
|
|
#include <asm/io.h>
|
|
#include <asm/bootinfo.h>
|
|
#include <asm/gt64120.h>
|
|
|
|
#define WRPPMC_CPU_CLK_FREQ 40000000 /* 40MHZ */
|
|
|
|
void __init plat_timer_setup(struct irqaction *irq)
|
|
{
|
|
/* Install ISR for timer interrupt */
|
|
setup_irq(WRPPMC_MIPS_TIMER_IRQ, irq);
|
|
}
|
|
|
|
/*
|
|
* Estimate CPU frequency. Sets mips_hpt_frequency as a side-effect
|
|
*
|
|
* NOTE: We disable all GT64120 timers, and use MIPS processor internal
|
|
* timer as the source of kernel clock tick.
|
|
*/
|
|
void __init wrppmc_time_init(void)
|
|
{
|
|
/* Disable GT64120 timers */
|
|
GT_WRITE(GT_TC_CONTROL_OFS, 0x00);
|
|
GT_WRITE(GT_TC0_OFS, 0x00);
|
|
GT_WRITE(GT_TC1_OFS, 0x00);
|
|
GT_WRITE(GT_TC2_OFS, 0x00);
|
|
GT_WRITE(GT_TC3_OFS, 0x00);
|
|
|
|
/* Use MIPS compare/count internal timer */
|
|
mips_hpt_frequency = WRPPMC_CPU_CLK_FREQ;
|
|
}
|