1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2004-2008 Sam Leffler, Errno Consulting
5 * Copyright (c) 2004 Video54 Technologies, Inc.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer,
13 *    without modification.
14 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
15 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
16 *    redistribution must be conditioned upon including a substantially
17 *    similar Disclaimer requirement for further binary redistribution.
18 *
19 * NO WARRANTY
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
23 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
24 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
25 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
28 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
30 * THE POSSIBILITY OF SUCH DAMAGES.
31 *
32 * $FreeBSD: releng/12.0/sys/dev/ath/if_athrate.h 326255 2017-11-27 14:52:40Z pfg $
33 */
34#ifndef _ATH_RATECTRL_H_
35#define _ATH_RATECTRL_H_
36
37/*
38 * Interface definitions for transmit rate control modules for the
39 * Atheros driver.
40 *
41 * A rate control module is responsible for choosing the transmit rate
42 * for each data frame.  Management+control frames are always sent at
43 * a fixed rate.
44 *
45 * Only one module may be present at a time; the driver references
46 * rate control interfaces by symbol name.  If multiple modules are
47 * to be supported we'll need to switch to a registration-based scheme
48 * as is currently done, for example, for authentication modules.
49 *
50 * An instance of the rate control module is attached to each device
51 * at attach time and detached when the device is destroyed.  The module
52 * may associate data with each device and each node (station).  Both
53 * sets of storage are opaque except for the size of the per-node storage
54 * which must be provided when the module is attached.
55 *
56 * The rate control module is notified for each state transition and
57 * station association/reassociation.  Otherwise it is queried for a
58 * rate for each outgoing frame and provided status from each transmitted
59 * frame.  Any ancillary processing is the responsibility of the module
60 * (e.g. if periodic processing is required then the module should setup
61 * it's own timer).
62 *
63 * In addition to the transmit rate for each frame the module must also
64 * indicate the number of attempts to make at the specified rate.  If this
65 * number is != ATH_TXMAXTRY then an additional callback is made to setup
66 * additional transmit state.  The rate control code is assumed to write
67 * this additional data directly to the transmit descriptor.
68 */
69struct ath_softc;
70struct ath_node;
71struct ath_desc;
72
73struct ath_ratectrl {
74	size_t	arc_space;	/* space required for per-node state */
75};
76/*
77 * Attach/detach a rate control module.
78 */
79struct ath_ratectrl *ath_rate_attach(struct ath_softc *);
80void	ath_rate_detach(struct ath_ratectrl *);
81
82#define	ATH_RC_NUM		4
83
84#define	ATH_RC_DS_FLAG		0x01	/* dual-stream rate */
85#define	ATH_RC_CW40_FLAG	0x02	/* use HT40 */
86#define	ATH_RC_SGI_FLAG		0x04	/* use short-GI */
87#define	ATH_RC_HT_FLAG		0x08	/* use HT */
88#define	ATH_RC_RTSCTS_FLAG	0x10	/* enable RTS/CTS protection */
89#define	ATH_RC_STBC_FLAG	0x20	/* enable STBC */
90#define	ATH_RC_TS_FLAG		0x40	/* triple-stream rate */
91
92struct ath_rc_series {
93	uint8_t rix;		/* ratetable index, not rate code */
94	uint8_t ratecode;	/* hardware rate code */
95	uint8_t tries;
96	uint8_t tx_power_cap;
97	uint16_t flags;
98	uint16_t max4msframelen;
99};
100
101/*
102 * State storage handling.
103 */
104/*
105 * Initialize per-node state already allocated for the specified
106 * node; this space can be assumed initialized to zero.
107 */
108void	ath_rate_node_init(struct ath_softc *, struct ath_node *);
109/*
110 * Cleanup any per-node state prior to the node being reclaimed.
111 */
112void	ath_rate_node_cleanup(struct ath_softc *, struct ath_node *);
113/*
114 * Update rate control state on station associate/reassociate
115 * (when operating as an ap or for nodes discovered when operating
116 * in ibss mode).
117 */
118void	ath_rate_newassoc(struct ath_softc *, struct ath_node *,
119		int isNewAssociation);
120
121/*
122 * Transmit handling.
123 */
124/*
125 * Return the four TX rate index and try counts for the current data packet.
126 */
127void	ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an,
128		uint8_t rix0, int is_aggr, struct ath_rc_series *rc);
129
130/*
131 * Return the transmit info for a data packet.  If multi-rate state
132 * is to be setup then try0 should contain a value other than ATH_TXMATRY
133 * and ath_rate_setupxtxdesc will be called after deciding if the frame
134 * can be transmitted with multi-rate retry.
135 *
136 * maxdur is an optional return value (or -1 if not set) that defines
137 * the maximum frame duration in microseconds.  This allows the rate
138 * control selection to override the maximum duration (normally 4ms)
139 * that the packet aggregation logic makes.
140 */
141void	ath_rate_findrate(struct ath_softc *, struct ath_node *,
142		int shortPreamble, size_t frameLen, int tid, int is_aggr,
143		u_int8_t *rix, int *try0, u_int8_t *txrate, int *maxdur,
144		int *maxpktlen);
145/*
146 * Setup any extended (multi-rate) descriptor state for a data packet.
147 * The rate index returned by ath_rate_findrate is passed back in.
148 */
149void	ath_rate_setupxtxdesc(struct ath_softc *, struct ath_node *,
150		struct ath_desc *, int shortPreamble, u_int8_t rix);
151/*
152 * Update rate control state for a packet associated with the
153 * supplied transmit descriptor.  The routine is invoked both
154 * for packets that were successfully sent and for those that
155 * failed (consult the descriptor for details).
156 *
157 * For A-MPDU frames, nframes and nbad indicate how many frames
158 * were in the aggregate, and how many failed.
159 */
160struct ath_buf;
161void	ath_rate_tx_complete(struct ath_softc *, struct ath_node *,
162		const struct ath_rc_series *, const struct ath_tx_status *,
163		int pktlen, int rc_framelen, int nframes, int nbad);
164
165/*
166 * Update rate control with a per-packet receive RSSI value.
167 */
168void	ath_rate_update_rx_rssi(struct ath_softc *, struct ath_node *,
169		int rssi);
170
171/*
172 * Fetch the global rate control statistics.
173 */
174int	ath_rate_fetch_stats(struct ath_softc *sc, struct ath_rateioctl *rs);
175
176/*
177 * Fetch the per-node statistics.
178 */
179int	ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an,
180		struct ath_rateioctl *rs);
181
182#endif /* _ATH_RATECTRL_H_ */
183