40 lines
935 B
C
40 lines
935 B
C
// SPDX-License-Identifier: GPL-2.0
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// Copyright (C) 2005-2017 Andes Technology Corporation
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#ifndef __NDS32_DELAY_H__
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#define __NDS32_DELAY_H__
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#include <asm/param.h>
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/* There is no clocksource cycle counter in the CPU. */
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static inline void __delay(unsigned long loops)
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{
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__asm__ __volatile__(".align 2\n"
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"1:\n"
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"\taddi\t%0, %0, -1\n"
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"\tbgtz\t%0, 1b\n"
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:"=r"(loops)
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:"0"(loops));
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}
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static inline void __udelay(unsigned long usecs, unsigned long lpj)
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{
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usecs *= (unsigned long)(((0x8000000000000000ULL / (500000 / HZ)) +
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0x80000000ULL) >> 32);
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usecs = (unsigned long)(((unsigned long long)usecs * lpj) >> 32);
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__delay(usecs);
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}
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#define udelay(usecs) __udelay((usecs), loops_per_jiffy)
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/* make sure "usecs *= ..." in udelay do not overflow. */
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#if HZ >= 1000
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#define MAX_UDELAY_MS 1
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#elif HZ <= 200
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#define MAX_UDELAY_MS 5
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#else
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#define MAX_UDELAY_MS (1000 / HZ)
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#endif
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#endif
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