2 Copyright (C) 2001 Paul Davis
3 Code derived from various headers from the Linux kernel
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #ifndef __ardour_cycles_h__
22 #define __ardour_cycles_h__
26 #if defined(__i386__) || defined(__x86_64__)
29 * Standard way to access the cycle counter on i586+ CPUs.
30 * Currently only used on SMP.
32 * If you really have a SMP machine with i486 chips or older,
33 * compile for that, and this will just always return zero.
34 * That's ok, it just means that the nicer scheduling heuristics
37 * We only use the low 32 bits, and we'd simply better make sure
38 * that we reschedule before that wraps. Scheduling at least every
39 * four billion cycles just basically sounds like a good idea,
40 * regardless of how fast the machine is.
42 typedef uint64_t cycles_t;
44 extern cycles_t cacheflush_time;
46 #if defined(__x86_64__)
48 #define rdtscll(lo, hi) \
49 __asm__ __volatile__("rdtsc" : "=a" (lo), "=d" (hi))
51 static inline cycles_t get_cycles (void)
61 #define rdtscll(val) \
62 __asm__ __volatile__("rdtsc" : "=A" (val))
64 static inline cycles_t get_cycles (void)
69 return ret & 0xffffffff;
73 #elif defined(__powerpc__)
75 #define CPU_FTR_601 0x00000100
77 typedef uint32_t cycles_t;
80 * For the "cycle" counter we use the timebase lower half.
81 * Currently only used on SMP.
84 extern cycles_t cacheflush_time;
86 static inline cycles_t get_cycles(void)
93 ".section __ftr_fixup,\"a\"\n"
99 : "=r" (ret) : "i" (CPU_FTR_601));
103 #elif defined(__ia64__)
106 typedef uint32_t cycles_t;
107 static inline cycles_t
111 __asm__ __volatile__ ("mov %0=ar.itc" : "=r"(ret));
115 #elif defined(__alpha__)
119 * Standard way to access the cycle counter.
120 * Currently only used on SMP for scheduling.
122 * Only the low 32 bits are available as a continuously counting entity.
123 * But this only means we'll force a reschedule every 8 seconds or so,
124 * which isn't an evil thing.
127 typedef uint32_t cycles_t;
128 static inline cycles_t get_cycles (void)
131 __asm__ __volatile__ ("rpcc %0" : "=r"(ret));
135 #elif defined(__s390__)
138 typedef uint32_t long cycles_t;
139 static inline cycles_t get_cycles(void)
142 __asm__("stck 0(%0)" : : "a" (&(cycles)) : "memory", "cc");
146 #elif defined(__hppa__)
149 #define mfctl(reg) ({ \
151 __asm__ __volatile__( \
152 "mfctl " #reg ",%0" : \
158 typedef uint32_t cycles_t;
159 static inline cycles_t get_cycles (void)
164 #elif defined(__mips__)
168 * Standard way to access the cycle counter.
169 * Currently only used on SMP for scheduling.
171 * Only the low 32 bits are available as a continuously counting entity.
172 * But this only means we'll force a reschedule every 8 seconds or so,
173 * which isn't an evil thing.
175 * We know that all SMP capable CPUs have cycle counters.
178 #define __read_32bit_c0_register(source, sel) \
181 __asm__ __volatile__( \
182 "mfc0\t%0, " #source "\n\t" \
185 __asm__ __volatile__( \
187 "mfc0\t%0, " #source ", " #sel "\n\t" \
193 /* #define CP0_COUNT $9 */
194 #define read_c0_count() __read_32bit_c0_register($9, 0)
196 typedef uint32_t cycles_t;
197 static inline cycles_t get_cycles (void)
199 return read_c0_count();
203 #elif defined(__APPLE__)
205 #include <CoreAudio/HostTime.h>
207 typedef UInt64 cycles_t;
208 static inline cycles_t get_cycles (void)
210 UInt64 time = AudioGetCurrentHostTime();
211 return AudioConvertHostTimeToNanos(time);
217 /* debian: sparc, arm, m68k */
219 #ifndef COMPILER_MSVC
220 /* GRRR... Annoyingly, #warning aborts the compilation for MSVC !! */
221 #warning You are compiling libardour on a platform for which ardour/cycles.h needs work
224 #include <sys/time.h>
226 typedef long cycles_t;
228 extern cycles_t cacheflush_time;
230 static inline cycles_t get_cycles(void)
233 gettimeofday (&tv, NULL);
240 #endif /* __ardour_cycles_h__ */