1 #ifndef _ASM_POWERPC_DELAY_H
2 #define _ASM_POWERPC_DELAY_H
5 * Copyright 1996, Paul Mackerras.
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
12 * PPC64 Support added by Dave Engebretsen, Todd Inglett, Mike Corrigan,
16 extern unsigned long tb_ticks_per_usec;
19 /* define these here to prevent circular dependencies */
20 /* these instructions control the thread priority on multi-threaded cpus */
21 #define __HMT_low() asm volatile("or 1,1,1")
22 #define __HMT_medium() asm volatile("or 2,2,2")
25 #define __HMT_medium()
28 #define __barrier() asm volatile("" ::: "memory")
30 static inline unsigned long __get_tb(void)
34 asm volatile("mftb %0" : "=r" (rval));
38 static inline void __delay(unsigned long loops)
40 unsigned long start = __get_tb();
42 while((__get_tb() - start) < loops)
48 static inline void udelay(unsigned long usecs)
50 unsigned long loops = tb_ticks_per_usec * usecs;
55 #endif /* _ASM_POWERPC_DELAY_H */