From a1df417e74aa6dae7352dc8cbb0ad471af5b7c69 Mon Sep 17 00:00:00 2001 From: "Michael J. Chudobiak" Date: Mon, 25 Apr 2016 10:00:44 -0400 Subject: initial Olimex linux tree from Daniel, originally Feb 3, 2016 --- linux/arch/openrisc/lib/delay.c | 60 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 linux/arch/openrisc/lib/delay.c (limited to 'linux/arch/openrisc/lib/delay.c') diff --git a/linux/arch/openrisc/lib/delay.c b/linux/arch/openrisc/lib/delay.c new file mode 100644 index 00000000..c82b09f4 --- /dev/null +++ b/linux/arch/openrisc/lib/delay.c @@ -0,0 +1,60 @@ +/* + * OpenRISC Linux + * + * Linux architectural port borrowing liberally from similar works of + * others. All original copyrights apply as per the original source + * declaration. + * + * Modifications for the OpenRISC architecture: + * Copyright (C) 2010-2011 Jonas Bonn + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation + * + * Precise Delay Loops + */ + +#include +#include +#include +#include +#include +#include + +int read_current_timer(unsigned long *timer_value) +{ + *timer_value = mfspr(SPR_TTCR); + return 0; +} + +void __delay(unsigned long cycles) +{ + cycles_t start = get_cycles(); + + while ((get_cycles() - start) < cycles) + cpu_relax(); +} +EXPORT_SYMBOL(__delay); + +inline void __const_udelay(unsigned long xloops) +{ + unsigned long long loops; + + loops = (unsigned long long)xloops * loops_per_jiffy * HZ; + + __delay(loops >> 32); +} +EXPORT_SYMBOL(__const_udelay); + +void __udelay(unsigned long usecs) +{ + __const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */ +} +EXPORT_SYMBOL(__udelay); + +void __ndelay(unsigned long nsecs) +{ + __const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */ +} +EXPORT_SYMBOL(__ndelay); -- cgit