1 /******************************************************************************
2  *
3  * Copyright(c) 2009-2012  Realtek Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * The full GNU General Public License is included in this distribution in the
15  * file called LICENSE.
16  *
17  * Contact Information:
18  * wlanfae <wlanfae@realtek.com>
19  * Realtek Corporation, No. 2, Innovation Road II, Hsinchu Science Park,
20  * Hsinchu 300, Taiwan.
21  *
22  * Larry Finger <Larry.Finger@lwfinger.net>
23  *
24  *****************************************************************************/
25 
26 #include "wifi.h"
27 #include "base.h"
28 #include "rc.h"
29 
30 /*
31  *Finds the highest rate index we can use
32  *if skb is special data like DHCP/EAPOL, we set should
33  *it to lowest rate CCK_1M, otherwise we set rate to
34  *highest rate based on wireless mode used for iwconfig
35  *show Tx rate.
36  */
37 static u8 _rtl_rc_get_highest_rix(struct rtl_priv *rtlpriv,
38 				  struct ieee80211_sta *sta,
39 				  struct sk_buff *skb, bool not_data)
40 {
41 	struct rtl_hal *rtlhal = rtl_hal(rtlpriv);
42 	struct rtl_phy *rtlphy = &(rtlpriv->phy);
43 	struct rtl_sta_info *sta_entry = NULL;
44 	u16 wireless_mode = 0;
45 
46 	/*
47 	 *this rate is no use for true rate, firmware
48 	 *will control rate at all it just used for
49 	 *1.show in iwconfig in B/G mode
50 	 *2.in rtl_get_tcb_desc when we check rate is
51 	 *      1M we will not use FW rate but user rate.
52 	 */
53 
54 	if (sta) {
55 		sta_entry = (struct rtl_sta_info *)sta->drv_priv;
56 		wireless_mode = sta_entry->wireless_mode;
57 	}
58 
59 	if (rtl_is_special_data(rtlpriv->mac80211.hw, skb, true, false) ||
60 	    not_data) {
61 		return 0;
62 	} else {
63 		if (rtlhal->current_bandtype == BAND_ON_2_4G) {
64 			if (wireless_mode == WIRELESS_MODE_B) {
65 				return B_MODE_MAX_RIX;
66 			} else if (wireless_mode == WIRELESS_MODE_G) {
67 				return G_MODE_MAX_RIX;
68 			} else if (wireless_mode == WIRELESS_MODE_N_24G) {
69 				if (get_rf_type(rtlphy) != RF_2T2R)
70 					return N_MODE_MCS7_RIX;
71 				else
72 					return N_MODE_MCS15_RIX;
73 			} else if (wireless_mode == WIRELESS_MODE_AC_24G) {
74 				return AC_MODE_MCS9_RIX;
75 			}
76 			return 0;
77 		} else {
78 			if (wireless_mode == WIRELESS_MODE_A) {
79 				return A_MODE_MAX_RIX;
80 			} else if (wireless_mode == WIRELESS_MODE_N_5G) {
81 				if (get_rf_type(rtlphy) != RF_2T2R)
82 					return N_MODE_MCS7_RIX;
83 				else
84 					return N_MODE_MCS15_RIX;
85 			} else if (wireless_mode == WIRELESS_MODE_AC_5G) {
86 				return AC_MODE_MCS9_RIX;
87 			}
88 			return 0;
89 		}
90 	}
91 }
92 
93 static void _rtl_rc_rate_set_series(struct rtl_priv *rtlpriv,
94 				    struct ieee80211_sta *sta,
95 				    struct ieee80211_tx_rate *rate,
96 				    struct ieee80211_tx_rate_control *txrc,
97 				    u8 tries, s8 rix, int rtsctsenable,
98 				    bool not_data)
99 {
100 	struct rtl_mac *mac = rtl_mac(rtlpriv);
101 	struct rtl_sta_info *sta_entry = NULL;
102 	u16 wireless_mode = 0;
103 	u8 sgi_20 = 0, sgi_40 = 0, sgi_80 = 0;
104 
105 	if (sta) {
106 		sgi_20 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_20;
107 		sgi_40 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40;
108 		sgi_80 = sta->vht_cap.cap & IEEE80211_VHT_CAP_SHORT_GI_80;
109 		sta_entry = (struct rtl_sta_info *)sta->drv_priv;
110 		wireless_mode = sta_entry->wireless_mode;
111 	}
112 	rate->count = tries;
113 	rate->idx = rix >= 0x00 ? rix : 0x00;
114 	if (rtlpriv->rtlhal.hw_type == HARDWARE_TYPE_RTL8812AE &&
115 	    wireless_mode == WIRELESS_MODE_AC_5G)
116 		rate->idx += 0x10;/*2NSS for 8812AE*/
117 
118 	if (!not_data) {
119 		if (txrc->short_preamble)
120 			rate->flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
121 		if (mac->opmode == NL80211_IFTYPE_AP ||
122 			mac->opmode == NL80211_IFTYPE_ADHOC) {
123 			if (sta && (sta->ht_cap.cap &
124 				    IEEE80211_HT_CAP_SUP_WIDTH_20_40))
125 				rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
126 			if (sta && (sta->vht_cap.vht_supported))
127 				rate->flags |= IEEE80211_TX_RC_80_MHZ_WIDTH;
128 		} else {
129 			if (mac->bw_40)
130 				rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
131 			if (mac->bw_80)
132 				rate->flags |= IEEE80211_TX_RC_80_MHZ_WIDTH;
133 		}
134 
135 		if (sgi_20 || sgi_40 || sgi_80)
136 			rate->flags |= IEEE80211_TX_RC_SHORT_GI;
137 		if (sta && sta->ht_cap.ht_supported &&
138 		    ((wireless_mode == WIRELESS_MODE_N_5G) ||
139 		     (wireless_mode == WIRELESS_MODE_N_24G)))
140 			rate->flags |= IEEE80211_TX_RC_MCS;
141 		if (sta && sta->vht_cap.vht_supported &&
142 		    (wireless_mode == WIRELESS_MODE_AC_5G ||
143 		     wireless_mode == WIRELESS_MODE_AC_24G ||
144 		     wireless_mode == WIRELESS_MODE_AC_ONLY))
145 			rate->flags |= IEEE80211_TX_RC_VHT_MCS;
146 	}
147 }
148 
149 static void rtl_get_rate(void *ppriv, struct ieee80211_sta *sta,
150 			 void *priv_sta,
151 			 struct ieee80211_tx_rate_control *txrc)
152 {
153 	struct rtl_priv *rtlpriv = ppriv;
154 	struct sk_buff *skb = txrc->skb;
155 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
156 	struct ieee80211_tx_rate *rates = tx_info->control.rates;
157 	__le16 fc = rtl_get_fc(skb);
158 	u8 try_per_rate, i, rix;
159 	bool not_data = !ieee80211_is_data(fc);
160 
161 	if (rate_control_send_low(sta, priv_sta, txrc))
162 		return;
163 
164 	rix = _rtl_rc_get_highest_rix(rtlpriv, sta, skb, not_data);
165 	try_per_rate = 1;
166 	_rtl_rc_rate_set_series(rtlpriv, sta, &rates[0], txrc,
167 				try_per_rate, rix, 1, not_data);
168 
169 	if (!not_data) {
170 		for (i = 1; i < 4; i++)
171 			_rtl_rc_rate_set_series(rtlpriv, sta, &rates[i],
172 						txrc, i, (rix - i), 1,
173 						not_data);
174 	}
175 }
176 
177 static bool _rtl_tx_aggr_check(struct rtl_priv *rtlpriv,
178 			       struct rtl_sta_info *sta_entry, u16 tid)
179 {
180 	struct rtl_mac *mac = rtl_mac(rtlpriv);
181 
182 	if (mac->act_scanning)
183 		return false;
184 
185 	if (mac->opmode == NL80211_IFTYPE_STATION &&
186 	    mac->cnt_after_linked < 3)
187 		return false;
188 
189 	if (sta_entry->tids[tid].agg.agg_state == RTL_AGG_STOP)
190 		return true;
191 
192 	return false;
193 }
194 
195 /*mac80211 Rate Control callbacks*/
196 static void rtl_tx_status(void *ppriv,
197 			  struct ieee80211_supported_band *sband,
198 			  struct ieee80211_sta *sta, void *priv_sta,
199 			  struct sk_buff *skb)
200 {
201 	struct rtl_priv *rtlpriv = ppriv;
202 	struct rtl_mac *mac = rtl_mac(rtlpriv);
203 	struct ieee80211_hdr *hdr = rtl_get_hdr(skb);
204 	__le16 fc = rtl_get_fc(skb);
205 	struct rtl_sta_info *sta_entry;
206 
207 	if (!priv_sta || !ieee80211_is_data(fc))
208 		return;
209 
210 	if (rtl_is_special_data(mac->hw, skb, true, true))
211 		return;
212 
213 	if (is_multicast_ether_addr(ieee80211_get_DA(hdr)) ||
214 	    is_broadcast_ether_addr(ieee80211_get_DA(hdr)))
215 		return;
216 
217 	if (sta) {
218 		/* Check if aggregation has to be enabled for this tid */
219 		sta_entry = (struct rtl_sta_info *) sta->drv_priv;
220 		if ((sta->ht_cap.ht_supported) &&
221 		    !(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
222 			if (ieee80211_is_data_qos(fc)) {
223 				u8 tid = rtl_get_tid(skb);
224 				if (_rtl_tx_aggr_check(rtlpriv, sta_entry,
225 						       tid)) {
226 					sta_entry->tids[tid].agg.agg_state =
227 						RTL_AGG_PROGRESS;
228 					ieee80211_start_tx_ba_session(sta, tid,
229 								      5000);
230 				}
231 			}
232 		}
233 	}
234 }
235 
236 static void rtl_rate_init(void *ppriv,
237 			  struct ieee80211_supported_band *sband,
238 			  struct cfg80211_chan_def *chandef,
239 			  struct ieee80211_sta *sta, void *priv_sta)
240 {
241 }
242 
243 static void rtl_rate_update(void *ppriv,
244 			    struct ieee80211_supported_band *sband,
245 			    struct cfg80211_chan_def *chandef,
246 			    struct ieee80211_sta *sta, void *priv_sta,
247 			    u32 changed)
248 {
249 }
250 
251 static void *rtl_rate_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
252 {
253 	struct rtl_priv *rtlpriv = rtl_priv(hw);
254 	return rtlpriv;
255 }
256 
257 static void rtl_rate_free(void *rtlpriv)
258 {
259 	return;
260 }
261 
262 static void *rtl_rate_alloc_sta(void *ppriv,
263 				struct ieee80211_sta *sta, gfp_t gfp)
264 {
265 	struct rtl_priv *rtlpriv = ppriv;
266 	struct rtl_rate_priv *rate_priv;
267 
268 	rate_priv = kzalloc(sizeof(struct rtl_rate_priv), gfp);
269 	if (!rate_priv) {
270 		pr_err("Unable to allocate private rc structure\n");
271 		return NULL;
272 	}
273 
274 	rtlpriv->rate_priv = rate_priv;
275 
276 	return rate_priv;
277 }
278 
279 static void rtl_rate_free_sta(void *rtlpriv,
280 			      struct ieee80211_sta *sta, void *priv_sta)
281 {
282 	struct rtl_rate_priv *rate_priv = priv_sta;
283 	kfree(rate_priv);
284 }
285 
286 static struct rate_control_ops rtl_rate_ops = {
287 	.name = "rtl_rc",
288 	.alloc = rtl_rate_alloc,
289 	.free = rtl_rate_free,
290 	.alloc_sta = rtl_rate_alloc_sta,
291 	.free_sta = rtl_rate_free_sta,
292 	.rate_init = rtl_rate_init,
293 	.rate_update = rtl_rate_update,
294 	.tx_status = rtl_tx_status,
295 	.get_rate = rtl_get_rate,
296 };
297 
298 int rtl_rate_control_register(void)
299 {
300 	return ieee80211_rate_control_register(&rtl_rate_ops);
301 }
302 
303 void rtl_rate_control_unregister(void)
304 {
305 	ieee80211_rate_control_unregister(&rtl_rate_ops);
306 }
307