diff options
Diffstat (limited to 'include/asm-cris/delay.h')
-rw-r--r-- | include/asm-cris/delay.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/include/asm-cris/delay.h b/include/asm-cris/delay.h new file mode 100644 index 000000000..7360b7bff --- /dev/null +++ b/include/asm-cris/delay.h @@ -0,0 +1,67 @@ +/* $Id: delay.h,v 1.2 2000/08/08 16:36:41 bjornw Exp $ */ + +#ifndef _CRIS_DELAY_H +#define _CRIS_DELAY_H + +/* + * Copyright (C) 1998, 1999, 2000 Axis Communications AB + * + * Delay routines, using a pre-computed "loops_per_second" value. + */ + +#include <linux/config.h> +#include <linux/linkage.h> + +#ifdef CONFIG_SMP +#include <asm/smp.h> +#endif + +extern void __do_delay(void); /* Special register call calling convention */ + +extern __inline__ void __delay(int loops) +{ + /* need to be a great deal of nops, because Etrax shuts off IRQ's during a branch + and we depend on the irq's to measure the time! */ + + __asm__ __volatile__ ( + "move.d %0,r0\n" + "1:\n\t" + "nop\n\t" + "nop\n\t" + "nop\n\t" + "nop\n\t" + "nop\n\t" + "nop\n\t" + "nop\n\t" + "subq 1,r0\n\t" + "bne 1b\n\t" + "nop\n\t" + : : "r" (loops) : "r0", "cc"); +} + + +/* + * Use only for very small delays ( < 1 msec). Should probably use a + * lookup table, really, as the multiplications take much too long with + * short delays. This is a "reasonable" implementation, though (and the + * first constant multiplications gets optimized away if the delay is + * a constant) + */ + +extern unsigned long loops_per_usec; /* arch/cris/mm/init.c */ + +extern __inline__ void udelay(unsigned long usecs) +{ + __delay(usecs * loops_per_usec); +} + +extern __inline__ unsigned long muldiv(unsigned long a, unsigned long b, unsigned long c) +{ + printk("muldiv called!\n"); + return 0; +} + +#endif /* defined(_ETRAX_DELAY_H) */ + + + |