1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
4 */
5
6#ifndef __RC_MINSTREL_HT_H
7#define __RC_MINSTREL_HT_H
8
9#include <linux/bitfield.h>
10
11/* number of highest throughput rates to consider*/
12#define MAX_THR_RATES 4
13#define SAMPLE_COLUMNS	10	/* number of columns in sample table */
14
15/* scaled fraction values */
16#define MINSTREL_SCALE  12
17#define MINSTREL_FRAC(val, div) (((val) << MINSTREL_SCALE) / div)
18#define MINSTREL_TRUNC(val) ((val) >> MINSTREL_SCALE)
19
20#define EWMA_LEVEL	96	/* ewma weighting factor [/EWMA_DIV] */
21#define EWMA_DIV	128
22
23/*
24 * Coefficients for moving average with noise filter (period=16),
25 * scaled by 10 bits
26 *
27 * a1 = exp(-pi * sqrt(2) / period)
28 * coeff2 = 2 * a1 * cos(sqrt(2) * 2 * pi / period)
29 * coeff3 = -sqr(a1)
30 * coeff1 = 1 - coeff2 - coeff3
31 */
32#define MINSTREL_AVG_COEFF1		(MINSTREL_FRAC(1, 1) - \
33					 MINSTREL_AVG_COEFF2 - \
34					 MINSTREL_AVG_COEFF3)
35#define MINSTREL_AVG_COEFF2		0x00001499
36#define MINSTREL_AVG_COEFF3		-0x0000092e
37
38/*
39 * The number of streams can be changed to 2 to reduce code
40 * size and memory footprint.
41 */
42#define MINSTREL_MAX_STREAMS		4
43#define MINSTREL_HT_STREAM_GROUPS	4 /* BW(=2) * SGI(=2) */
44#define MINSTREL_VHT_STREAM_GROUPS	6 /* BW(=3) * SGI(=2) */
45
46#define MINSTREL_HT_GROUPS_NB	(MINSTREL_MAX_STREAMS *		\
47				 MINSTREL_HT_STREAM_GROUPS)
48#define MINSTREL_VHT_GROUPS_NB	(MINSTREL_MAX_STREAMS *		\
49				 MINSTREL_VHT_STREAM_GROUPS)
50#define MINSTREL_LEGACY_GROUPS_NB	2
51#define MINSTREL_GROUPS_NB	(MINSTREL_HT_GROUPS_NB +	\
52				 MINSTREL_VHT_GROUPS_NB +	\
53				 MINSTREL_LEGACY_GROUPS_NB)
54
55#define MINSTREL_HT_GROUP_0	0
56#define MINSTREL_CCK_GROUP	(MINSTREL_HT_GROUP_0 + MINSTREL_HT_GROUPS_NB)
57#define MINSTREL_OFDM_GROUP	(MINSTREL_CCK_GROUP + 1)
58#define MINSTREL_VHT_GROUP_0	(MINSTREL_OFDM_GROUP + 1)
59
60#define MCS_GROUP_RATES		10
61
62#define MI_RATE_IDX_MASK	GENMASK(3, 0)
63#define MI_RATE_GROUP_MASK	GENMASK(15, 4)
64
65#define MI_RATE(_group, _idx)				\
66	(FIELD_PREP(MI_RATE_GROUP_MASK, _group) |	\
67	 FIELD_PREP(MI_RATE_IDX_MASK, _idx))
68
69#define MI_RATE_IDX(_rate) FIELD_GET(MI_RATE_IDX_MASK, _rate)
70#define MI_RATE_GROUP(_rate) FIELD_GET(MI_RATE_GROUP_MASK, _rate)
71
72#define MINSTREL_SAMPLE_RATES		5 /* rates per sample type */
73#define MINSTREL_SAMPLE_INTERVAL	(HZ / 50)
74
75struct minstrel_priv {
76	struct ieee80211_hw *hw;
77	unsigned int cw_min;
78	unsigned int cw_max;
79	unsigned int max_retry;
80	unsigned int segment_size;
81	unsigned int update_interval;
82
83	u8 cck_rates[4];
84	u8 ofdm_rates[NUM_NL80211_BANDS][8];
85
86#ifdef CONFIG_MAC80211_DEBUGFS
87	/*
88	 * enable fixed rate processing per RC
89	 *   - write static index to debugfs:ieee80211/phyX/rc/fixed_rate_idx
90	 *   - write -1 to enable RC processing again
91	 *   - setting will be applied on next update
92	 */
93	u32 fixed_rate_idx;
94#endif
95};
96
97
98struct mcs_group {
99	u16 flags;
100	u8 streams;
101	u8 shift;
102	u8 bw;
103	u16 duration[MCS_GROUP_RATES];
104};
105
106extern const s16 minstrel_cck_bitrates[4];
107extern const s16 minstrel_ofdm_bitrates[8];
108extern const struct mcs_group minstrel_mcs_groups[];
109
110struct minstrel_rate_stats {
111	/* current / last sampling period attempts/success counters */
112	u16 attempts, last_attempts;
113	u16 success, last_success;
114
115	/* total attempts/success counters */
116	u32 att_hist, succ_hist;
117
118	/* prob_avg - moving average of prob */
119	u16 prob_avg;
120	u16 prob_avg_1;
121
122	/* maximum retry counts */
123	u8 retry_count;
124	u8 retry_count_rtscts;
125
126	bool retry_updated;
127};
128
129enum minstrel_sample_type {
130	MINSTREL_SAMPLE_TYPE_INC,
131	MINSTREL_SAMPLE_TYPE_JUMP,
132	MINSTREL_SAMPLE_TYPE_SLOW,
133	__MINSTREL_SAMPLE_TYPE_MAX
134};
135
136struct minstrel_mcs_group_data {
137	u8 index;
138	u8 column;
139
140	/* sorted rate set within a MCS group*/
141	u16 max_group_tp_rate[MAX_THR_RATES];
142	u16 max_group_prob_rate;
143
144	/* MCS rate statistics */
145	struct minstrel_rate_stats rates[MCS_GROUP_RATES];
146};
147
148struct minstrel_sample_category {
149	u8 sample_group;
150	u16 sample_rates[MINSTREL_SAMPLE_RATES];
151	u16 cur_sample_rates[MINSTREL_SAMPLE_RATES];
152};
153
154struct minstrel_ht_sta {
155	struct ieee80211_sta *sta;
156
157	/* ampdu length (average, per sampling interval) */
158	unsigned int ampdu_len;
159	unsigned int ampdu_packets;
160
161	/* ampdu length (EWMA) */
162	unsigned int avg_ampdu_len;
163
164	/* overall sorted rate set */
165	u16 max_tp_rate[MAX_THR_RATES];
166	u16 max_prob_rate;
167
168	/* time of last status update */
169	unsigned long last_stats_update;
170
171	/* overhead time in usec for each frame */
172	unsigned int overhead;
173	unsigned int overhead_rtscts;
174	unsigned int overhead_legacy;
175	unsigned int overhead_legacy_rtscts;
176
177	unsigned int total_packets;
178	unsigned int sample_packets;
179
180	/* tx flags to add for frames for this sta */
181	u32 tx_flags;
182	bool use_short_preamble;
183	u8 band;
184
185	u8 sample_seq;
186	u16 sample_rate;
187
188	unsigned long sample_time;
189	struct minstrel_sample_category sample[__MINSTREL_SAMPLE_TYPE_MAX];
190
191	/* Bitfield of supported MCS rates of all groups */
192	u16 supported[MINSTREL_GROUPS_NB];
193
194	/* MCS rate group info and statistics */
195	struct minstrel_mcs_group_data groups[MINSTREL_GROUPS_NB];
196};
197
198void minstrel_ht_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
199int minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate,
200			   int prob_avg);
201
202#endif
203