1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2009-2012  Realtek Corporation.*/
3 
4 #include "wifi.h"
5 #include "base.h"
6 #include "rc.h"
7 
8 /*
9  *Finds the highest rate index we can use
10  *if skb is special data like DHCP/EAPOL, we set should
11  *it to lowest rate CCK_1M, otherwise we set rate to
12  *highest rate based on wireless mode used for iwconfig
13  *show Tx rate.
14  */
15 static u8 _rtl_rc_get_highest_rix(struct rtl_priv *rtlpriv,
16 				  struct ieee80211_sta *sta,
17 				  struct sk_buff *skb, bool not_data)
18 {
19 	struct rtl_hal *rtlhal = rtl_hal(rtlpriv);
20 	struct rtl_phy *rtlphy = &(rtlpriv->phy);
21 	struct rtl_sta_info *sta_entry = NULL;
22 	u16 wireless_mode = 0;
23 	u8 nss;
24 	struct ieee80211_tx_rate rate;
25 
26 	switch (get_rf_type(rtlphy)) {
27 	case RF_4T4R:
28 		nss = 4;
29 		break;
30 	case RF_3T3R:
31 		nss = 3;
32 		break;
33 	case RF_2T2R:
34 		nss = 2;
35 		break;
36 	default:
37 		nss = 1;
38 		break;
39 	}
40 
41 	/*
42 	 *this rate is no use for true rate, firmware
43 	 *will control rate at all it just used for
44 	 *1.show in iwconfig in B/G mode
45 	 *2.in rtl_get_tcb_desc when we check rate is
46 	 *      1M we will not use FW rate but user rate.
47 	 */
48 
49 	if (sta) {
50 		sta_entry = (struct rtl_sta_info *)sta->drv_priv;
51 		wireless_mode = sta_entry->wireless_mode;
52 	}
53 
54 	if (rtl_is_special_data(rtlpriv->mac80211.hw, skb, true, false) ||
55 	    not_data) {
56 		return 0;
57 	} else {
58 		if (rtlhal->current_bandtype == BAND_ON_2_4G) {
59 			if (wireless_mode == WIRELESS_MODE_B) {
60 				return B_MODE_MAX_RIX;
61 			} else if (wireless_mode == WIRELESS_MODE_G) {
62 				return G_MODE_MAX_RIX;
63 			} else if (wireless_mode == WIRELESS_MODE_N_24G) {
64 				if (nss == 1)
65 					return N_MODE_MCS7_RIX;
66 				else
67 					return N_MODE_MCS15_RIX;
68 			} else if (wireless_mode == WIRELESS_MODE_AC_24G) {
69 				if (sta->bandwidth == IEEE80211_STA_RX_BW_20) {
70 					ieee80211_rate_set_vht(&rate,
71 							       AC_MODE_MCS8_RIX,
72 							       nss);
73 					goto out;
74 				} else {
75 					ieee80211_rate_set_vht(&rate,
76 							       AC_MODE_MCS9_RIX,
77 							       nss);
78 					goto out;
79 				}
80 			}
81 			return 0;
82 		} else {
83 			if (wireless_mode == WIRELESS_MODE_A) {
84 				return A_MODE_MAX_RIX;
85 			} else if (wireless_mode == WIRELESS_MODE_N_5G) {
86 				if (nss == 1)
87 					return N_MODE_MCS7_RIX;
88 				else
89 					return N_MODE_MCS15_RIX;
90 			} else if (wireless_mode == WIRELESS_MODE_AC_5G) {
91 				if (sta->bandwidth == IEEE80211_STA_RX_BW_20) {
92 					ieee80211_rate_set_vht(&rate,
93 							       AC_MODE_MCS8_RIX,
94 							       nss);
95 					goto out;
96 				} else {
97 					ieee80211_rate_set_vht(&rate,
98 							       AC_MODE_MCS9_RIX,
99 							       nss);
100 					goto out;
101 				}
102 			}
103 			return 0;
104 		}
105 	}
106 
107 out:
108 	return rate.idx;
109 }
110 
111 static void _rtl_rc_rate_set_series(struct rtl_priv *rtlpriv,
112 				    struct ieee80211_sta *sta,
113 				    struct ieee80211_tx_rate *rate,
114 				    struct ieee80211_tx_rate_control *txrc,
115 				    u8 tries, s8 rix, int rtsctsenable,
116 				    bool not_data)
117 {
118 	struct rtl_mac *mac = rtl_mac(rtlpriv);
119 	struct rtl_sta_info *sta_entry = NULL;
120 	u16 wireless_mode = 0;
121 	u8 sgi_20 = 0, sgi_40 = 0, sgi_80 = 0;
122 
123 	if (sta) {
124 		sgi_20 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_20;
125 		sgi_40 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40;
126 		sgi_80 = sta->vht_cap.cap & IEEE80211_VHT_CAP_SHORT_GI_80;
127 		sta_entry = (struct rtl_sta_info *)sta->drv_priv;
128 		wireless_mode = sta_entry->wireless_mode;
129 	}
130 	rate->count = tries;
131 	rate->idx = rix >= 0x00 ? rix : 0x00;
132 
133 	if (!not_data) {
134 		if (txrc->short_preamble)
135 			rate->flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
136 		if (mac->opmode == NL80211_IFTYPE_AP ||
137 			mac->opmode == NL80211_IFTYPE_ADHOC) {
138 			if (sta && (sta->ht_cap.cap &
139 				    IEEE80211_HT_CAP_SUP_WIDTH_20_40))
140 				rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
141 			if (sta && sta->vht_cap.vht_supported)
142 				rate->flags |= IEEE80211_TX_RC_80_MHZ_WIDTH;
143 		} else {
144 			if (mac->bw_80)
145 				rate->flags |= IEEE80211_TX_RC_80_MHZ_WIDTH;
146 			else if (mac->bw_40)
147 				rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
148 		}
149 
150 		if (sgi_20 || sgi_40 || sgi_80)
151 			rate->flags |= IEEE80211_TX_RC_SHORT_GI;
152 		if (sta && sta->ht_cap.ht_supported &&
153 		    (wireless_mode == WIRELESS_MODE_N_5G ||
154 		     wireless_mode == WIRELESS_MODE_N_24G))
155 			rate->flags |= IEEE80211_TX_RC_MCS;
156 		if (sta && sta->vht_cap.vht_supported &&
157 		    (wireless_mode == WIRELESS_MODE_AC_5G ||
158 		     wireless_mode == WIRELESS_MODE_AC_24G ||
159 		     wireless_mode == WIRELESS_MODE_AC_ONLY))
160 			rate->flags |= IEEE80211_TX_RC_VHT_MCS;
161 	}
162 }
163 
164 static void rtl_get_rate(void *ppriv, struct ieee80211_sta *sta,
165 			 void *priv_sta,
166 			 struct ieee80211_tx_rate_control *txrc)
167 {
168 	struct rtl_priv *rtlpriv = ppriv;
169 	struct sk_buff *skb = txrc->skb;
170 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
171 	struct ieee80211_tx_rate *rates = tx_info->control.rates;
172 	__le16 fc = rtl_get_fc(skb);
173 	u8 try_per_rate, i, rix;
174 	bool not_data = !ieee80211_is_data(fc);
175 
176 	rix = _rtl_rc_get_highest_rix(rtlpriv, sta, skb, not_data);
177 	try_per_rate = 1;
178 	_rtl_rc_rate_set_series(rtlpriv, sta, &rates[0], txrc,
179 				try_per_rate, rix, 1, not_data);
180 
181 	if (!not_data) {
182 		for (i = 1; i < 4; i++)
183 			_rtl_rc_rate_set_series(rtlpriv, sta, &rates[i],
184 						txrc, i, (rix - i), 1,
185 						not_data);
186 	}
187 }
188 
189 static bool _rtl_tx_aggr_check(struct rtl_priv *rtlpriv,
190 			       struct rtl_sta_info *sta_entry, u16 tid)
191 {
192 	struct rtl_mac *mac = rtl_mac(rtlpriv);
193 
194 	if (mac->act_scanning)
195 		return false;
196 
197 	if (mac->opmode == NL80211_IFTYPE_STATION &&
198 	    mac->cnt_after_linked < 3)
199 		return false;
200 
201 	if (sta_entry->tids[tid].agg.agg_state == RTL_AGG_STOP)
202 		return true;
203 
204 	return false;
205 }
206 
207 /*mac80211 Rate Control callbacks*/
208 static void rtl_tx_status(void *ppriv,
209 			  struct ieee80211_supported_band *sband,
210 			  struct ieee80211_sta *sta, void *priv_sta,
211 			  struct sk_buff *skb)
212 {
213 	struct rtl_priv *rtlpriv = ppriv;
214 	struct rtl_mac *mac = rtl_mac(rtlpriv);
215 	struct ieee80211_hdr *hdr = rtl_get_hdr(skb);
216 	__le16 fc = rtl_get_fc(skb);
217 	struct rtl_sta_info *sta_entry;
218 
219 	if (!priv_sta || !ieee80211_is_data(fc))
220 		return;
221 
222 	if (rtl_is_special_data(mac->hw, skb, true, true))
223 		return;
224 
225 	if (is_multicast_ether_addr(ieee80211_get_DA(hdr)) ||
226 	    is_broadcast_ether_addr(ieee80211_get_DA(hdr)))
227 		return;
228 
229 	if (sta) {
230 		/* Check if aggregation has to be enabled for this tid */
231 		sta_entry = (struct rtl_sta_info *)sta->drv_priv;
232 		if (sta->ht_cap.ht_supported &&
233 		    !(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
234 			if (ieee80211_is_data_qos(fc)) {
235 				u8 tid = rtl_get_tid(skb);
236 
237 				if (_rtl_tx_aggr_check(rtlpriv, sta_entry,
238 						       tid)) {
239 					sta_entry->tids[tid].agg.agg_state =
240 						RTL_AGG_PROGRESS;
241 					ieee80211_start_tx_ba_session(sta, tid,
242 								      5000);
243 				}
244 			}
245 		}
246 	}
247 }
248 
249 static void rtl_rate_init(void *ppriv,
250 			  struct ieee80211_supported_band *sband,
251 			  struct cfg80211_chan_def *chandef,
252 			  struct ieee80211_sta *sta, void *priv_sta)
253 {
254 }
255 
256 static void rtl_rate_update(void *ppriv,
257 			    struct ieee80211_supported_band *sband,
258 			    struct cfg80211_chan_def *chandef,
259 			    struct ieee80211_sta *sta, void *priv_sta,
260 			    u32 changed)
261 {
262 }
263 
264 static void *rtl_rate_alloc(struct ieee80211_hw *hw)
265 {
266 	struct rtl_priv *rtlpriv = rtl_priv(hw);
267 	return rtlpriv;
268 }
269 
270 static void rtl_rate_free(void *rtlpriv)
271 {
272 	return;
273 }
274 
275 static void *rtl_rate_alloc_sta(void *ppriv,
276 				struct ieee80211_sta *sta, gfp_t gfp)
277 {
278 	struct rtl_priv *rtlpriv = ppriv;
279 	struct rtl_rate_priv *rate_priv;
280 
281 	rate_priv = kzalloc(sizeof(*rate_priv), gfp);
282 	if (!rate_priv)
283 		return NULL;
284 
285 	rtlpriv->rate_priv = rate_priv;
286 
287 	return rate_priv;
288 }
289 
290 static void rtl_rate_free_sta(void *rtlpriv,
291 			      struct ieee80211_sta *sta, void *priv_sta)
292 {
293 	struct rtl_rate_priv *rate_priv = priv_sta;
294 
295 	kfree(rate_priv);
296 }
297 
298 static const struct rate_control_ops rtl_rate_ops = {
299 	.name = "rtl_rc",
300 	.alloc = rtl_rate_alloc,
301 	.free = rtl_rate_free,
302 	.alloc_sta = rtl_rate_alloc_sta,
303 	.free_sta = rtl_rate_free_sta,
304 	.rate_init = rtl_rate_init,
305 	.rate_update = rtl_rate_update,
306 	.tx_status = rtl_tx_status,
307 	.get_rate = rtl_get_rate,
308 };
309 
310 int rtl_rate_control_register(void)
311 {
312 	return ieee80211_rate_control_register(&rtl_rate_ops);
313 }
314 
315 void rtl_rate_control_unregister(void)
316 {
317 	ieee80211_rate_control_unregister(&rtl_rate_ops);
318 }
319