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* Copyright (C) 2005-2008 by Pieter Palmers
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* This file is part of FFADO
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* FFADO = Free Firewire (pro-)audio drivers for linux
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* FFADO is based upon FreeBoB.
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 2 of the License, or
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* (at your option) version 3 of the License.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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* Based upon cycles.h from the jackdmp package.
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* Copyright (C) 2001 Paul Davis
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* Code derived from various headers from the Linux kernel
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) version 3 of the License.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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#ifndef __FFADO_CYCLES_H__
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#define __FFADO_CYCLES_H__
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* Standard way to access the cycle timer on i586+ CPUs.
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* Currently only used on SMP.
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* If you really have a SMP machine with i486 chips or older,
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* compile for that, and this will just always return zero.
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* That's ok, it just means that the nicer scheduling heuristics
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* We only use the low 32 bits, and we'd simply better make sure
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* that we reschedule before that wraps. Scheduling at least every
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* four billion cycles just basically sounds like a good idea,
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* regardless of how fast the machine is.
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#define CPU_FTR_601 0x00000100
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typedef unsigned long cycles_t;
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/* For the "cycle" counter we use the timebase lower half. */
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extern cycles_t cacheflush_time;
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static inline cycles_t get_cycles(void)
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".section __ftr_fixup,\"a\"\n"
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: "=r" (ret) : "i" (CPU_FTR_601));
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typedef unsigned long long cycles_t;
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extern cycles_t cacheflush_time;
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#define rdtscll(val) \
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__asm__ __volatile__("rdtsc" : "=A" (val))
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static inline cycles_t get_cycles (void)
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unsigned long long ret;
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#endif // __FFADO_CYCLES_H__
added
removed
src/libutil/cycles.h
