summaryrefslogtreecommitdiffstats
path: root/drivers/net/wireless/ath9k/rc.h
blob: b95b41508b986000174519cc451458962f4962c3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
/*
 * Copyright (c) 2004 Sam Leffler, Errno Consulting
 * Copyright (c) 2004 Video54 Technologies, Inc.
 * Copyright (c) 2008 Atheros Communications Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef RC_H
#define RC_H

#include "ath9k.h"
/*
 * Interface definitions for transmit rate control modules for the
 * Atheros driver.
 *
 * A rate control module is responsible for choosing the transmit rate
 * for each data frame.  Management+control frames are always sent at
 * a fixed rate.
 *
 * Only one module may be present at a time; the driver references
 * rate control interfaces by symbol name.  If multiple modules are
 * to be supported we'll need to switch to a registration-based scheme
 * as is currently done, for example, for authentication modules.
 *
 * An instance of the rate control module is attached to each device
 * at attach time and detached when the device is destroyed.  The module
 * may associate data with each device and each node (station).  Both
 * sets of storage are opaque except for the size of the per-node storage
 * which must be provided when the module is attached.
 *
 * The rate control module is notified for each state transition and
 * station association/reassociation.  Otherwise it is queried for a
 * rate for each outgoing frame and provided status from each transmitted
 * frame.  Any ancillary processing is the responsibility of the module
 * (e.g. if periodic processing is required then the module should setup
 * it's own timer).
 *
 * In addition to the transmit rate for each frame the module must also
 * indicate the number of attempts to make at the specified rate.  If this
 * number is != ATH_TXMAXTRY then an additional callback is made to setup
 * additional transmit state.  The rate control code is assumed to write
 * this additional data directly to the transmit descriptor.
 */

struct ath_softc;

#define TRUE 1
#define FALSE 0

#define ATH_RATE_MAX	30
#define MCS_SET_SIZE	128

enum ieee80211_fixed_rate_mode {
	IEEE80211_FIXED_RATE_NONE  = 0,
	IEEE80211_FIXED_RATE_MCS   = 1  /* HT rates */
};

/*
 * Use the hal os glue code to get ms time
 */
#define IEEE80211_RATE_IDX_ENTRY(val, idx) (((val&(0xff<<(idx*8)))>>(idx*8)))

#define WLAN_PHY_HT_20_SS       WLAN_RC_PHY_HT_20_SS
#define WLAN_PHY_HT_20_DS       WLAN_RC_PHY_HT_20_DS
#define WLAN_PHY_HT_20_DS_HGI   WLAN_RC_PHY_HT_20_DS_HGI
#define WLAN_PHY_HT_40_SS       WLAN_RC_PHY_HT_40_SS
#define WLAN_PHY_HT_40_SS_HGI   WLAN_RC_PHY_HT_40_SS_HGI
#define WLAN_PHY_HT_40_DS       WLAN_RC_PHY_HT_40_DS
#define WLAN_PHY_HT_40_DS_HGI   WLAN_RC_PHY_HT_40_DS_HGI

#define WLAN_PHY_OFDM	PHY_OFDM
#define WLAN_PHY_CCK	PHY_CCK

#define TRUE_20		0x2
#define TRUE_40		0x4
#define TRUE_2040	(TRUE_20|TRUE_40)
#define TRUE_ALL	(TRUE_2040|TRUE)

enum {
	WLAN_RC_PHY_HT_20_SS = 4,
	WLAN_RC_PHY_HT_20_DS,
	WLAN_RC_PHY_HT_40_SS,
	WLAN_RC_PHY_HT_40_DS,
	WLAN_RC_PHY_HT_20_SS_HGI,
	WLAN_RC_PHY_HT_20_DS_HGI,
	WLAN_RC_PHY_HT_40_SS_HGI,
	WLAN_RC_PHY_HT_40_DS_HGI,
	WLAN_RC_PHY_MAX
};

#define WLAN_RC_PHY_DS(_phy)   ((_phy == WLAN_RC_PHY_HT_20_DS)		\
				|| (_phy == WLAN_RC_PHY_HT_40_DS)	\
				|| (_phy == WLAN_RC_PHY_HT_20_DS_HGI)	\
				|| (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
#define WLAN_RC_PHY_40(_phy)   ((_phy == WLAN_RC_PHY_HT_40_SS)		\
				|| (_phy == WLAN_RC_PHY_HT_40_DS)	\
				|| (_phy == WLAN_RC_PHY_HT_40_SS_HGI)	\
				|| (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
#define WLAN_RC_PHY_SGI(_phy)  ((_phy == WLAN_RC_PHY_HT_20_SS_HGI)      \
				|| (_phy == WLAN_RC_PHY_HT_20_DS_HGI)   \
				|| (_phy == WLAN_RC_PHY_HT_40_SS_HGI)   \
				|| (_phy == WLAN_RC_PHY_HT_40_DS_HGI))

#define WLAN_RC_PHY_HT(_phy)    (_phy >= WLAN_RC_PHY_HT_20_SS)

/* Returns the capflag mode */
#define WLAN_RC_CAP_MODE(capflag) (((capflag & WLAN_RC_HT_FLAG) ?	\
		(capflag & WLAN_RC_40_FLAG) ? TRUE_40 : TRUE_20 : TRUE))

/* Return TRUE if flag supports HT20 && client supports HT20 or
 * return TRUE if flag supports HT40 && client supports HT40.
 * This is used becos some rates overlap between HT20/HT40.
 */

#define WLAN_RC_PHY_HT_VALID(flag, capflag) (((flag & TRUE_20) && !(capflag \
				& WLAN_RC_40_FLAG)) || ((flag & TRUE_40) && \
				  (capflag & WLAN_RC_40_FLAG)))

#define WLAN_RC_DS_FLAG         (0x01)
#define WLAN_RC_40_FLAG         (0x02)
#define WLAN_RC_SGI_FLAG        (0x04)
#define WLAN_RC_HT_FLAG         (0x08)

#define RATE_TABLE_SIZE		64

/**
 * struct ath_rate_table - Rate Control table
 * @valid: valid for use in rate control
 * @valid_single_stream: valid for use in rate control for
 * 	single stream operation
 * @phy: CCK/OFDM
 * @ratekbps: rate in Kbits per second
 * @user_ratekbps: user rate in Kbits per second
 * @ratecode: rate that goes into HW descriptors
 * @short_preamble: Mask for enabling short preamble in ratecode for CCK
 * @dot11rate: value that goes into supported
 * 	rates info element of MLME
 * @ctrl_rate: Index of next lower basic rate, used for duration computation
 * @max_4ms_framelen: maximum frame length(bytes) for tx duration
 * @probe_interval: interval for rate control to probe for other rates
 * @rssi_reduce_interval: interval for rate control to reduce rssi
 * @initial_ratemax: initial ratemax value used in ath_rc_sib_update()
 */
struct ath_rate_table {
	int rate_cnt;
	struct {
		int valid;
		int valid_single_stream;
		u8 phy;
		u32 ratekbps;
		u32 user_ratekbps;
		u8 ratecode;
		u8 short_preamble;
		u8 dot11rate;
		u8 ctrl_rate;
		int8_t rssi_ack_validmin;
		int8_t rssi_ack_deltamin;
		u8 base_index;
		u8 cw40index;
		u8 sgi_index;
		u8 ht_index;
		u32 max_4ms_framelen;
	} info[RATE_TABLE_SIZE];
	u32 probe_interval;
	u32 rssi_reduce_interval;
	u8 initial_ratemax;
};

#define ATH_RC_PROBE_ALLOWED            0x00000001
#define ATH_RC_MINRATE_LASTRATE         0x00000002

struct ath_rc_series {
	u8 rix;
	u8 tries;
	u8 flags;
	u32 max_4ms_framelen;
};

/* rcs_flags definition */
#define ATH_RC_DS_FLAG               0x01
#define ATH_RC_CW40_FLAG             0x02    /* CW 40 */
#define ATH_RC_SGI_FLAG              0x04    /* Short Guard Interval */
#define ATH_RC_HT_FLAG               0x08    /* HT */
#define ATH_RC_RTSCTS_FLAG           0x10    /* RTS-CTS */

/*
 * State structures for new rate adaptation code
 */
#define	MAX_TX_RATE_TBL	        64
#define MAX_TX_RATE_PHY         48

struct ath_tx_ratectrl_state {
	int8_t rssi_thres;	/* required rssi for this rate (dB) */
	u8 per;			/* recent estimate of packet error rate (%) */
};

/**
 * struct ath_tx_ratectrl - TX Rate control Information
 * @state: RC state
 * @rssi_last: last ACK rssi
 * @rssi_last_lookup: last ACK rssi used for lookup
 * @rssi_last_prev: previous last ACK rssi
 * @rssi_last_prev2: 2nd previous last ACK rssi
 * @rssi_sum_cnt: count of rssi_sum for averaging
 * @rssi_sum_rate: rate that we are averaging
 * @rssi_sum: running sum of rssi for averaging
 * @probe_rate: rate we are probing at
 * @rssi_time: msec timestamp for last ack rssi
 * @rssi_down_time: msec timestamp for last down step
 * @probe_time: msec timestamp for last probe
 * @hw_maxretry_pktcnt: num of packets since we got HW max retry error
 * @max_valid_rate: maximum number of valid rate
 * @per_down_time: msec timestamp for last PER down step
 * @valid_phy_ratecnt: valid rate count
 * @rate_max_phy: phy index for the max rate
 * @probe_interval: interval for ratectrl to probe for other rates
 */
struct ath_tx_ratectrl {
	struct ath_tx_ratectrl_state state[MAX_TX_RATE_TBL];
	int8_t rssi_last;
	int8_t rssi_last_lookup;
	int8_t rssi_last_prev;
	int8_t rssi_last_prev2;
	int32_t rssi_sum_cnt;
	int32_t rssi_sum_rate;
	int32_t rssi_sum;
	u8 rate_table_size;
	u8 probe_rate;
	u32 rssi_time;
	u32 rssi_down_time;
	u32 probe_time;
	u8 hw_maxretry_pktcnt;
	u8 max_valid_rate;
	u8 valid_rate_index[MAX_TX_RATE_TBL];
	u32 per_down_time;

	/* 11n state */
	u8 valid_phy_ratecnt[WLAN_RC_PHY_MAX];
	u8 valid_phy_rateidx[WLAN_RC_PHY_MAX][MAX_TX_RATE_TBL];
	u8 rc_phy_mode;
	u8 rate_max_phy;
	u32 probe_interval;
};

struct ath_rateset {
	u8 rs_nrates;
	u8 rs_rates[ATH_RATE_MAX];
};

/* per-device state */
struct ath_rate_softc {
	/* phy tables that contain rate control data */
	const void *hw_rate_table[ATH9K_MODE_MAX];

	/* -1 or index of fixed rate */
	int fixedrix;
};

/* per-node state */
struct ath_rate_node {
	struct ath_tx_ratectrl tx_ratectrl;

	/* rate idx of last data frame */
	u32 prev_data_rix;

	/* ht capabilities */
	u8 ht_cap;

	/* When TRUE, only single stream Tx possible */
	u8 single_stream;

	/* Negotiated rates */
	struct ath_rateset neg_rates;

	/* Negotiated HT rates */
	struct ath_rateset neg_ht_rates;

	struct ath_rate_softc *asc;
	struct ath_vap *avp;
};

/* Driver data of ieee80211_tx_info */
struct ath_tx_info_priv {
	struct ath_rc_series rcs[4];
	struct ath_tx_status tx;
	int n_frames;
	int n_bad_frames;
	u8 min_rate;
};

/*
 * Attach/detach a rate control module.
 */
struct ath_rate_softc *ath_rate_attach(struct ath_hal *ah);
void ath_rate_detach(struct ath_rate_softc *asc);

/*
 * Update/reset rate control state for 802.11 state transitions.
 * Important mostly as the analog to ath_rate_newassoc when operating
 * in station mode.
 */
void ath_rc_node_update(struct ieee80211_hw *hw, struct ath_rate_node *rc_priv);
void ath_rate_newstate(struct ath_softc *sc, struct ath_vap *avp);

/*
 * Return rate index for given Dot11 Rate.
 */
u8 ath_rate_findrateix(struct ath_softc *sc,
		       u8 dot11_rate);

/* Routines to register/unregister rate control algorithm */
int ath_rate_control_register(void);
void ath_rate_control_unregister(void);

#endif /* RC_H */