diff options
Diffstat (limited to 'kernel/arch/sh/lib64/udelay.c')
-rw-r--r-- | kernel/arch/sh/lib64/udelay.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/kernel/arch/sh/lib64/udelay.c b/kernel/arch/sh/lib64/udelay.c new file mode 100644 index 000000000..f215b063d --- /dev/null +++ b/kernel/arch/sh/lib64/udelay.c @@ -0,0 +1,49 @@ +/* + * arch/sh/lib64/udelay.c + * + * Delay routines, using a pre-computed "loops_per_jiffy" value. + * + * Copyright (C) 2000, 2001 Paolo Alberelli + * Copyright (C) 2003, 2004 Paul Mundt + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/sched.h> +#include <asm/param.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(unsigned long loops) +{ + long long dummy; + __asm__ __volatile__("gettr tr0, %1\n\t" + "pta $+4, tr0\n\t" + "addi %0, -1, %0\n\t" + "bne %0, r63, tr0\n\t" + "ptabs %1, tr0\n\t":"=r"(loops), + "=r"(dummy) + :"0"(loops)); +} + +void __const_udelay(unsigned long xloops) +{ + __delay(xloops * (HZ * cpu_data[raw_smp_processor_id()].loops_per_jiffy)); +} + +void __udelay(unsigned long usecs) +{ + __const_udelay(usecs * 0x000010c6); /* 2**32 / 1000000 */ +} + +void __ndelay(unsigned long nsecs) +{ + __const_udelay(nsecs * 0x00000005); +} |