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/*
* SH-Mobile Timer
*
* Copyright (C) 2010 Magnus Damm
* Copyright (C) 2002 - 2009 Paul Mundt
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/platform_device.h>
#include <linux/clocksource.h>
#include <linux/delay.h>
#include <linux/of_address.h>
#include "common.h"
void __init shmobile_init_delay(void)
{
struct device_node *np, *cpus;
u32 max_freq = 0;
cpus = of_find_node_by_path("/cpus");
if (!cpus)
return;
for_each_child_of_node(cpus, np) {
u32 freq;
if (IS_ENABLED(CONFIG_ARM_ARCH_TIMER) &&
(of_device_is_compatible(np, "arm,cortex-a7") ||
of_device_is_compatible(np, "arm,cortex-a15"))) {
of_node_put(np);
of_node_put(cpus);
return;
}
if (!of_property_read_u32(np, "clock-frequency", &freq))
max_freq = max(max_freq, freq);
}
of_node_put(cpus);
if (!max_freq)
return;
/*
* Calculate a worst-case loops-per-jiffy value
* based on maximum cpu core hz setting and the
* __delay() implementation in arch/arm/lib/delay.S.
*
* This will result in a longer delay than expected
* when the cpu core runs on lower frequencies.
*/
if (!preset_lpj)
preset_lpj = max_freq / HZ;
}
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