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 	if (rate_control_send_low(sta, priv_sta, txrc))
177 		return;
178 
179 	rix = _rtl_rc_get_highest_rix(rtlpriv, sta, skb, not_data);
180 	try_per_rate = 1;
181 	_rtl_rc_rate_set_series(rtlpriv, sta, &rates[0], txrc,
182 				try_per_rate, rix, 1, not_data);
183 
184 	if (!not_data) {
185 		for (i = 1; i < 4; i++)
186 			_rtl_rc_rate_set_series(rtlpriv, sta, &rates[i],
187 						txrc, i, (rix - i), 1,
188 						not_data);
189 	}
190 }
191 
192 static bool _rtl_tx_aggr_check(struct rtl_priv *rtlpriv,
193 			       struct rtl_sta_info *sta_entry, u16 tid)
194 {
195 	struct rtl_mac *mac = rtl_mac(rtlpriv);
196 
197 	if (mac->act_scanning)
198 		return false;
199 
200 	if (mac->opmode == NL80211_IFTYPE_STATION &&
201 	    mac->cnt_after_linked < 3)
202 		return false;
203 
204 	if (sta_entry->tids[tid].agg.agg_state == RTL_AGG_STOP)
205 		return true;
206 
207 	return false;
208 }
209 
210 /*mac80211 Rate Control callbacks*/
211 static void rtl_tx_status(void *ppriv,
212 			  struct ieee80211_supported_band *sband,
213 			  struct ieee80211_sta *sta, void *priv_sta,
214 			  struct sk_buff *skb)
215 {
216 	struct rtl_priv *rtlpriv = ppriv;
217 	struct rtl_mac *mac = rtl_mac(rtlpriv);
218 	struct ieee80211_hdr *hdr = rtl_get_hdr(skb);
219 	__le16 fc = rtl_get_fc(skb);
220 	struct rtl_sta_info *sta_entry;
221 
222 	if (!priv_sta || !ieee80211_is_data(fc))
223 		return;
224 
225 	if (rtl_is_special_data(mac->hw, skb, true, true))
226 		return;
227 
228 	if (is_multicast_ether_addr(ieee80211_get_DA(hdr)) ||
229 	    is_broadcast_ether_addr(ieee80211_get_DA(hdr)))
230 		return;
231 
232 	if (sta) {
233 		/* Check if aggregation has to be enabled for this tid */
234 		sta_entry = (struct rtl_sta_info *)sta->drv_priv;
235 		if (sta->ht_cap.ht_supported &&
236 		    !(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
237 			if (ieee80211_is_data_qos(fc)) {
238 				u8 tid = rtl_get_tid(skb);
239 
240 				if (_rtl_tx_aggr_check(rtlpriv, sta_entry,
241 						       tid)) {
242 					sta_entry->tids[tid].agg.agg_state =
243 						RTL_AGG_PROGRESS;
244 					ieee80211_start_tx_ba_session(sta, tid,
245 								      5000);
246 				}
247 			}
248 		}
249 	}
250 }
251 
252 static void rtl_rate_init(void *ppriv,
253 			  struct ieee80211_supported_band *sband,
254 			  struct cfg80211_chan_def *chandef,
255 			  struct ieee80211_sta *sta, void *priv_sta)
256 {
257 }
258 
259 static void rtl_rate_update(void *ppriv,
260 			    struct ieee80211_supported_band *sband,
261 			    struct cfg80211_chan_def *chandef,
262 			    struct ieee80211_sta *sta, void *priv_sta,
263 			    u32 changed)
264 {
265 }
266 
267 static void *rtl_rate_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
268 {
269 	struct rtl_priv *rtlpriv = rtl_priv(hw);
270 	return rtlpriv;
271 }
272 
273 static void rtl_rate_free(void *rtlpriv)
274 {
275 	return;
276 }
277 
278 static void *rtl_rate_alloc_sta(void *ppriv,
279 				struct ieee80211_sta *sta, gfp_t gfp)
280 {
281 	struct rtl_priv *rtlpriv = ppriv;
282 	struct rtl_rate_priv *rate_priv;
283 
284 	rate_priv = kzalloc(sizeof(*rate_priv), gfp);
285 	if (!rate_priv)
286 		return NULL;
287 
288 	rtlpriv->rate_priv = rate_priv;
289 
290 	return rate_priv;
291 }
292 
293 static void rtl_rate_free_sta(void *rtlpriv,
294 			      struct ieee80211_sta *sta, void *priv_sta)
295 {
296 	struct rtl_rate_priv *rate_priv = priv_sta;
297 
298 	kfree(rate_priv);
299 }
300 
301 static const struct rate_control_ops rtl_rate_ops = {
302 	.name = "rtl_rc",
303 	.alloc = rtl_rate_alloc,
304 	.free = rtl_rate_free,
305 	.alloc_sta = rtl_rate_alloc_sta,
306 	.free_sta = rtl_rate_free_sta,
307 	.rate_init = rtl_rate_init,
308 	.rate_update = rtl_rate_update,
309 	.tx_status = rtl_tx_status,
310 	.get_rate = rtl_get_rate,
311 };
312 
313 int rtl_rate_control_register(void)
314 {
315 	return ieee80211_rate_control_register(&rtl_rate_ops);
316 }
317 
318 void rtl_rate_control_unregister(void)
319 {
320 	ieee80211_rate_control_unregister(&rtl_rate_ops);
321 }
322