1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
4 */
5
6 #ifndef __RC_MINSTREL_H
7 #define __RC_MINSTREL_H
8
9 #define EWMA_LEVEL 96 /* ewma weighting factor [/EWMA_DIV] */
10 #define EWMA_DIV 128
11 #define SAMPLE_COLUMNS 10 /* number of columns in sample table */
12
13 /* scaled fraction values */
14 #define MINSTREL_SCALE 12
15 #define MINSTREL_FRAC(val, div) (((val) << MINSTREL_SCALE) / div)
16 #define MINSTREL_TRUNC(val) ((val) >> MINSTREL_SCALE)
17
18 /* number of highest throughput rates to consider*/
19 #define MAX_THR_RATES 4
20
21 /*
22 * Perform EWMA (Exponentially Weighted Moving Average) calculation
23 */
24 static inline int
minstrel_ewma(int old,int new,int weight)25 minstrel_ewma(int old, int new, int weight)
26 {
27 int diff, incr;
28
29 diff = new - old;
30 incr = (EWMA_DIV - weight) * diff / EWMA_DIV;
31
32 return old + incr;
33 }
34
35 struct minstrel_rate_stats {
36 /* current / last sampling period attempts/success counters */
37 u16 attempts, last_attempts;
38 u16 success, last_success;
39
40 /* total attempts/success counters */
41 u32 att_hist, succ_hist;
42
43 /* prob_ewma - exponential weighted moving average of prob */
44 u16 prob_ewma;
45
46 /* maximum retry counts */
47 u8 retry_count;
48 u8 retry_count_rtscts;
49
50 u8 sample_skipped;
51 bool retry_updated;
52 };
53
54 struct minstrel_rate {
55 int bitrate;
56
57 s8 rix;
58 u8 retry_count_cts;
59 u8 adjusted_retry_count;
60
61 unsigned int perfect_tx_time;
62 unsigned int ack_time;
63
64 int sample_limit;
65
66 struct minstrel_rate_stats stats;
67 };
68
69 struct minstrel_sta_info {
70 struct ieee80211_sta *sta;
71
72 unsigned long last_stats_update;
73 unsigned int sp_ack_dur;
74 unsigned int rate_avg;
75
76 unsigned int lowest_rix;
77
78 u8 max_tp_rate[MAX_THR_RATES];
79 u8 max_prob_rate;
80 unsigned int total_packets;
81 unsigned int sample_packets;
82 int sample_deferred;
83
84 unsigned int sample_row;
85 unsigned int sample_column;
86
87 int n_rates;
88 struct minstrel_rate *r;
89 bool prev_sample;
90
91 /* sampling table */
92 u8 *sample_table;
93 };
94
95 struct minstrel_priv {
96 struct ieee80211_hw *hw;
97 bool has_mrr;
98 u32 sample_switch;
99 unsigned int cw_min;
100 unsigned int cw_max;
101 unsigned int max_retry;
102 unsigned int segment_size;
103 unsigned int update_interval;
104 unsigned int lookaround_rate;
105 unsigned int lookaround_rate_mrr;
106
107 u8 cck_rates[4];
108
109 #ifdef CONFIG_MAC80211_DEBUGFS
110 /*
111 * enable fixed rate processing per RC
112 * - write static index to debugfs:ieee80211/phyX/rc/fixed_rate_idx
113 * - write -1 to enable RC processing again
114 * - setting will be applied on next update
115 */
116 u32 fixed_rate_idx;
117 #endif
118 };
119
120 struct minstrel_debugfs_info {
121 size_t len;
122 char buf[];
123 };
124
125 extern const struct rate_control_ops mac80211_minstrel;
126 void minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir);
127
128 /* Recalculate success probabilities and counters for a given rate using EWMA */
129 void minstrel_calc_rate_stats(struct minstrel_rate_stats *mrs);
130 int minstrel_get_tp_avg(struct minstrel_rate *mr, int prob_ewma);
131
132 /* debugfs */
133 int minstrel_stats_open(struct inode *inode, struct file *file);
134 int minstrel_stats_csv_open(struct inode *inode, struct file *file);
135
136 #endif
137