// SPDX-License-Identifier: GPL-2.0 /* * Precise Delay Loops for SuperH * * Copyright (C) 1999 Niibe Yutaka & Kaz Kojima */ #include <linux/sched.h> #include <linux/delay.h> void __delay(unsigned long loops) { __asm__ __volatile__( /* * ST40-300 appears to have an issue with this code, * normally taking two cycles each loop, as with all * other SH variants. If however the branch and the * delay slot straddle an 8 byte boundary, this increases * to 3 cycles. * This align directive ensures this doesn't occur. */ ".balign 8\n\t" "tst %0, %0\n\t" "1:\t" "bf/s 1b\n\t" " dt %0" : "=r" (loops) : "0" (loops) : "t"); } inline void __const_udelay(unsigned long xloops) { xloops *= 4; __asm__("dmulu.l %0, %2\n\t" "sts mach, %0" : "=r" (xloops) : "0" (xloops), "r" (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4)) : "macl", "mach"); __delay(++xloops); } void __udelay(unsigned long usecs) { __const_udelay(usecs * 0x000010c6); /* 2**32 / 1000000 */ } void __ndelay(unsigned long nsecs) { __const_udelay(nsecs * 0x00000005); }