include/sys/_ffcounter.h

0001 /**
0002  * @file
0003  *
0004  * @ingroup RTEMSScoreTimecounter
0005  *
0006  * @brief This header file provides interfaces of the feed-forward clock
0007  *   counter.
0008  */
0009
0010 /*-
0011  * SPDX-License-Identifier: BSD-2-Clause
0012  *
0013  * Copyright (c) 2011 The University of Melbourne
0014  * All rights reserved.
0015  *
0016  * This software was developed by Julien Ridoux at the University of Melbourne
0017  * under sponsorship from the FreeBSD Foundation.
0018  *
0019  * Redistribution and use in source and binary forms, with or without
0020  * modification, are permitted provided that the following conditions
0021  * are met:
0022  * 1. Redistributions of source code must retain the above copyright
0023  *    notice, this list of conditions and the following disclaimer.
0024  * 2. Redistributions in binary form must reproduce the above copyright
0025  *    notice, this list of conditions and the following disclaimer in the
0026  *    documentation and/or other materials provided with the distribution.
0027  *
0028  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
0029  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0030  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0031  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
0032  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
0033  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
0034  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
0035  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
0036  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
0037  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
0038  * SUCH DAMAGE.
0039  */
0040
0041 #ifndef _SYS__FFCOUNTER_H_
0042 #define _SYS__FFCOUNTER_H_
0043
0044 /*
0045  * The feed-forward clock counter. The fundamental element of a feed-forward
0046  * clock is a wide monotonically increasing counter that accumulates at the same
0047  * rate as the selected timecounter.
0048  */
0049 typedef uint64_t ffcounter;
0050
0051 #endif /* _SYS__FFCOUNTER_H_ */