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Diffstat (limited to 'arch/sh64/lib/udelay.c')
| -rw-r--r-- | arch/sh64/lib/udelay.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/sh64/lib/udelay.c b/arch/sh64/lib/udelay.c new file mode 100644 index 00000000000..dad2f254efe --- /dev/null +++ b/arch/sh64/lib/udelay.c @@ -0,0 +1,60 @@ +/* + * arch/sh64/lib/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/config.h> +#include <linux/sched.h> +#include <asm/param.h> + +extern unsigned long loops_per_jiffy; + +/* + * 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) +{ + 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 __udelay(unsigned long long usecs, unsigned long lpj) +{ + usecs *= (((unsigned long long) HZ << 32) / 1000000) * lpj; + __delay((long long) usecs >> 32); +} + +void __ndelay(unsigned long long nsecs, unsigned long lpj) +{ + nsecs *= (((unsigned long long) HZ << 32) / 1000000000) * lpj; + __delay((long long) nsecs >> 32); +} + +void udelay(unsigned long usecs) +{ + __udelay(usecs, loops_per_jiffy); +} + +void ndelay(unsigned long nsecs) +{ + __ndelay(nsecs, loops_per_jiffy); +} + |