1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_IA64_TIMEX_H 3 #define _ASM_IA64_TIMEX_H 4 5 /* 6 * Copyright (C) 1998-2001, 2003 Hewlett-Packard Co 7 * David Mosberger-Tang <davidm@hpl.hp.com> 8 */ 9 /* 10 * 2001/01/18 davidm Removed CLOCK_TICK_RATE. It makes no sense on IA-64. 11 * Also removed cacheflush_time as it's entirely unused. 12 */ 13 14 #include <asm/intrinsics.h> 15 #include <asm/processor.h> 16 17 typedef unsigned long cycles_t; 18 19 extern void (*ia64_udelay)(unsigned long usecs); 20 21 /* 22 * For performance reasons, we don't want to define CLOCK_TICK_TRATE as 23 * local_cpu_data->itc_rate. Fortunately, we don't have to, either: according to George 24 * Anzinger, 1/CLOCK_TICK_RATE is taken as the resolution of the timer clock. The time 25 * calculation assumes that you will use enough of these so that your tick size <= 1/HZ. 26 * If the calculation shows that your CLOCK_TICK_RATE can not supply exactly 1/HZ ticks, 27 * the actual value is calculated and used to update the wall clock each jiffie. Setting 28 * the CLOCK_TICK_RATE to x*HZ insures that the calculation will find no errors. Hence we 29 * pick a multiple of HZ which gives us a (totally virtual) CLOCK_TICK_RATE of about 30 * 100MHz. 31 */ 32 #define CLOCK_TICK_RATE (HZ * 100000UL) 33 34 static inline cycles_t 35 get_cycles (void) 36 { 37 cycles_t ret; 38 39 ret = ia64_getreg(_IA64_REG_AR_ITC); 40 return ret; 41 } 42 43 extern void ia64_cpu_local_tick (void); 44 extern unsigned long long ia64_native_sched_clock (void); 45 46 #endif /* _ASM_IA64_TIMEX_H */ 47