mirror of https://gitee.com/openkylin/linux.git
40 lines
1.1 KiB
C
40 lines
1.1 KiB
C
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/*
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* time.c: MIPS CPU Count/Compare timer hookup
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*
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* Author: Mark.Zhan, <rongkai.zhan@windriver.com>
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 1996, 1997, 2004 by Ralf Baechle (ralf@linux-mips.org)
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* Copyright (C) 2006, Wind River System Inc.
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*/
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <asm/gt64120.h>
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#include <asm/time.h>
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#define WRPPMC_CPU_CLK_FREQ 40000000 /* 40MHZ */
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/*
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* Estimate CPU frequency. Sets mips_hpt_frequency as a side-effect
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*
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* NOTE: We disable all GT64120 timers, and use MIPS processor internal
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* timer as the source of kernel clock tick.
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*/
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void __init plat_time_init(void)
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{
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/* Disable GT64120 timers */
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GT_WRITE(GT_TC_CONTROL_OFS, 0x00);
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GT_WRITE(GT_TC0_OFS, 0x00);
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GT_WRITE(GT_TC1_OFS, 0x00);
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GT_WRITE(GT_TC2_OFS, 0x00);
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GT_WRITE(GT_TC3_OFS, 0x00);
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/* Use MIPS compare/count internal timer */
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mips_hpt_frequency = WRPPMC_CPU_CLK_FREQ;
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}
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