1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer,
12 *    without modification.
13 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
14 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
15 *    redistribution must be conditioned upon including a substantially
16 *    similar Disclaimer requirement for further binary redistribution.
17 *
18 * NO WARRANTY
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
22 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
23 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
24 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
27 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
29 * THE POSSIBILITY OF SUCH DAMAGES.
30 *
31 * $FreeBSD: releng/12.0/sys/dev/ath/if_ath_tsf.h 326255 2017-11-27 14:52:40Z pfg $
32 */
33#ifndef	__IF_ATH_TSF_H__
34#define	__IF_ATH_TSF_H__
35
36/*
37 * Extend 15-bit time stamp from rx descriptor to
38 * a full 64-bit TSF using the specified TSF.
39 */
40static __inline u_int64_t
41ath_extend_tsf15(u_int32_t rstamp, u_int64_t tsf)
42{
43	if ((tsf & 0x7fff) < rstamp)
44		tsf -= 0x8000;
45
46	return ((tsf &~ 0x7fff) | rstamp);
47}
48
49/*
50 * Extend 32-bit time stamp from rx descriptor to
51 * a full 64-bit TSF using the specified TSF.
52 */
53static __inline u_int64_t
54ath_extend_tsf32(u_int32_t rstamp, u_int64_t tsf)
55{
56	u_int32_t tsf_low = tsf & 0xffffffff;
57	u_int64_t tsf64 = (tsf & ~0xffffffffULL) | rstamp;
58
59	if (rstamp > tsf_low && (rstamp - tsf_low > 0x10000000))
60		tsf64 -= 0x100000000ULL;
61
62	if (rstamp < tsf_low && (tsf_low - rstamp > 0x10000000))
63		tsf64 += 0x100000000ULL;
64
65	return tsf64;
66}
67
68/*
69 * Extend the TSF from the RX descriptor to a full 64 bit TSF.
70 * Earlier hardware versions only wrote the low 15 bits of the
71 * TSF into the RX descriptor; later versions (AR5416 and up)
72 * include the 32 bit TSF value.
73 */
74static __inline u_int64_t
75ath_extend_tsf(struct ath_softc *sc, u_int32_t rstamp, u_int64_t tsf)
76{
77	if (sc->sc_rxtsf32)
78		return ath_extend_tsf32(rstamp, tsf);
79	else
80		return ath_extend_tsf15(rstamp, tsf);
81}
82
83#endif
84