diff options
Diffstat (limited to 'arch/openrisc/lib/delay.c')
| -rw-r--r-- | arch/openrisc/lib/delay.c | 60 | 
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/openrisc/lib/delay.c b/arch/openrisc/lib/delay.c new file mode 100644 index 00000000000..c82b09f4a10 --- /dev/null +++ b/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 <jonas@southpole.se> + * + *      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 <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <asm/delay.h> +#include <asm/timex.h> +#include <asm/processor.h> + +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);  | 
