Files
android/arch/alpha/lib/udelay.c
T
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

57 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 1993, 2000 Linus Torvalds
*
* Delay routines, using a pre-computed "loops_per_jiffy" value.
*/
#include <linux/module.h>
#include <linux/sched.h> /* for udelay's use of smp_processor_id */
#include <asm/param.h>
#include <asm/smp.h>
#include <linux/delay.h>
/*
* Use only for very small delays (< 1 msec).
*
* The active part of our cycle counter is only 32-bits wide, and
* we're treating the difference between two marks as signed. On
* a 1GHz box, that's about 2 seconds.
*/
void
__delay(int loops)
{
int tmp;
__asm__ __volatile__(
" rpcc %0\n"
" addl %1,%0,%1\n"
"1: rpcc %0\n"
" subl %1,%0,%0\n"
" bgt %0,1b"
: "=&r" (tmp), "=r" (loops) : "1"(loops));
}
EXPORT_SYMBOL(__delay);
#ifdef CONFIG_SMP
#define LPJ cpu_data[smp_processor_id()].loops_per_jiffy
#else
#define LPJ loops_per_jiffy
#endif
void
udelay(unsigned long usecs)
{
usecs *= (((unsigned long)HZ << 32) / 1000000) * LPJ;
__delay((long)usecs >> 32);
}
EXPORT_SYMBOL(udelay);
void
ndelay(unsigned long nsecs)
{
nsecs *= (((unsigned long)HZ << 32) / 1000000000) * LPJ;
__delay((long)nsecs >> 32);
}
EXPORT_SYMBOL(ndelay);