mirror of https://gitee.com/openkylin/linux.git
42 lines
853 B
C
42 lines
853 B
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* SH-Mobile Timer
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*
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* Copyright (C) 2010 Magnus Damm
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* Copyright (C) 2002 - 2009 Paul Mundt
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*/
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#include <linux/platform_device.h>
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#include <linux/clocksource.h>
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#include <linux/delay.h>
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#include <linux/of_address.h>
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#include "common.h"
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void __init shmobile_init_delay(void)
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{
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struct device_node *np;
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u32 max_freq = 0;
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for_each_of_cpu_node(np) {
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u32 freq;
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if (!of_property_read_u32(np, "clock-frequency", &freq))
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max_freq = max(max_freq, freq);
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}
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if (!max_freq)
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return;
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/*
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* Calculate a worst-case loops-per-jiffy value
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* based on maximum cpu core hz setting and the
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* __delay() implementation in arch/arm/lib/delay.S.
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*
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* This will result in a longer delay than expected
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* when the cpu core runs on lower frequencies.
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*/
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if (!preset_lpj)
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preset_lpj = max_freq / HZ;
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}
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