1 // SPDX-License-Identifier: ISC
2 /*
3  * Copyright (C) 2018 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
4  */
5 
6 #include "mt76x02_usb.h"
7 
mt76x02u_remove_dma_hdr(struct sk_buff * skb)8 static void mt76x02u_remove_dma_hdr(struct sk_buff *skb)
9 {
10 	int hdr_len;
11 
12 	skb_pull(skb, sizeof(struct mt76x02_txwi) + MT_DMA_HDR_LEN);
13 	hdr_len = ieee80211_get_hdrlen_from_skb(skb);
14 	if (hdr_len % 4)
15 		mt76x02_remove_hdr_pad(skb, 2);
16 }
17 
mt76x02u_tx_complete_skb(struct mt76_dev * mdev,struct mt76_queue_entry * e)18 void mt76x02u_tx_complete_skb(struct mt76_dev *mdev, struct mt76_queue_entry *e)
19 {
20 	mt76x02u_remove_dma_hdr(e->skb);
21 	mt76_tx_complete_skb(mdev, e->wcid, e->skb);
22 }
23 EXPORT_SYMBOL_GPL(mt76x02u_tx_complete_skb);
24 
mt76x02u_mac_start(struct mt76x02_dev * dev)25 int mt76x02u_mac_start(struct mt76x02_dev *dev)
26 {
27 	mt76x02_mac_reset_counters(dev);
28 
29 	mt76_wr(dev, MT_MAC_SYS_CTRL, MT_MAC_SYS_CTRL_ENABLE_TX);
30 	if (!mt76x02_wait_for_wpdma(&dev->mt76, 200000))
31 		return -ETIMEDOUT;
32 
33 	mt76_wr(dev, MT_RX_FILTR_CFG, dev->mt76.rxfilter);
34 
35 	mt76_wr(dev, MT_MAC_SYS_CTRL,
36 		MT_MAC_SYS_CTRL_ENABLE_TX |
37 		MT_MAC_SYS_CTRL_ENABLE_RX);
38 
39 	if (!mt76x02_wait_for_wpdma(&dev->mt76, 50))
40 		return -ETIMEDOUT;
41 
42 	return 0;
43 }
44 EXPORT_SYMBOL_GPL(mt76x02u_mac_start);
45 
mt76x02u_skb_dma_info(struct sk_buff * skb,int port,u32 flags)46 int mt76x02u_skb_dma_info(struct sk_buff *skb, int port, u32 flags)
47 {
48 	u32 info, pad;
49 
50 	/* Buffer layout:
51 	 *	|   4B   | xfer len |      pad       |  4B  |
52 	 *	| TXINFO | pkt/cmd  | zero pad to 4B | zero |
53 	 *
54 	 * length field of TXINFO should be set to 'xfer len'.
55 	 */
56 	info = FIELD_PREP(MT_TXD_INFO_LEN, round_up(skb->len, 4)) |
57 	       FIELD_PREP(MT_TXD_INFO_DPORT, port) | flags;
58 	put_unaligned_le32(info, skb_push(skb, sizeof(info)));
59 
60 	pad = round_up(skb->len, 4) + 4 - skb->len;
61 	return mt76_skb_adjust_pad(skb, pad);
62 }
63 
mt76x02u_tx_prepare_skb(struct mt76_dev * mdev,void * data,enum mt76_txq_id qid,struct mt76_wcid * wcid,struct ieee80211_sta * sta,struct mt76_tx_info * tx_info)64 int mt76x02u_tx_prepare_skb(struct mt76_dev *mdev, void *data,
65 			    enum mt76_txq_id qid, struct mt76_wcid *wcid,
66 			    struct ieee80211_sta *sta,
67 			    struct mt76_tx_info *tx_info)
68 {
69 	struct mt76x02_dev *dev = container_of(mdev, struct mt76x02_dev, mt76);
70 	int pid, len = tx_info->skb->len, ep = q2ep(dev->mphy.q_tx[qid]->hw_idx);
71 	struct mt76x02_txwi *txwi;
72 	bool ampdu = IEEE80211_SKB_CB(tx_info->skb)->flags & IEEE80211_TX_CTL_AMPDU;
73 	enum mt76_qsel qsel;
74 	u32 flags;
75 	int err;
76 
77 	mt76_insert_hdr_pad(tx_info->skb);
78 
79 	txwi = (struct mt76x02_txwi *)(tx_info->skb->data - sizeof(*txwi));
80 	mt76x02_mac_write_txwi(dev, txwi, tx_info->skb, wcid, sta, len);
81 	skb_push(tx_info->skb, sizeof(*txwi));
82 
83 	pid = mt76_tx_status_skb_add(mdev, wcid, tx_info->skb);
84 
85 	/* encode packet rate for no-skb packet id to fix up status reporting */
86 	if (pid == MT_PACKET_ID_NO_SKB)
87 		pid = MT_PACKET_ID_HAS_RATE |
88 		      (le16_to_cpu(txwi->rate) & MT_PKTID_RATE) |
89 		      FIELD_PREP(MT_PKTID_AC,
90 				 skb_get_queue_mapping(tx_info->skb));
91 
92 	txwi->pktid = pid;
93 
94 	if ((mt76_is_skb_pktid(pid) && ampdu) || ep == MT_EP_OUT_HCCA)
95 		qsel = MT_QSEL_MGMT;
96 	else
97 		qsel = MT_QSEL_EDCA;
98 
99 	flags = FIELD_PREP(MT_TXD_INFO_QSEL, qsel) |
100 		MT_TXD_INFO_80211;
101 	if (!wcid || wcid->hw_key_idx == 0xff || wcid->sw_iv)
102 		flags |= MT_TXD_INFO_WIV;
103 
104 	if (sta) {
105 		struct mt76x02_sta *msta = (struct mt76x02_sta *)sta->drv_priv;
106 
107 		ewma_pktlen_add(&msta->pktlen, tx_info->skb->len);
108 	}
109 
110 	err = mt76x02u_skb_dma_info(tx_info->skb, WLAN_PORT, flags);
111 	if (err && wcid)
112 		/* Release pktid in case of error. */
113 		idr_remove(&wcid->pktid, pid);
114 
115 	return err;
116 }
117 EXPORT_SYMBOL_GPL(mt76x02u_tx_prepare_skb);
118 
119 /* Trigger pre-TBTT event 8 ms before TBTT */
120 #define PRE_TBTT_USEC 8000
121 
122 /* Beacon SRAM memory is limited to 8kB. We need to send PS buffered frames
123  * (which can be 1500 bytes big) via beacon memory. That make limit of number
124  * of slots to 5. TODO: dynamically calculate offsets in beacon SRAM.
125  */
126 #define N_BCN_SLOTS 5
127 
mt76x02u_start_pre_tbtt_timer(struct mt76x02_dev * dev)128 static void mt76x02u_start_pre_tbtt_timer(struct mt76x02_dev *dev)
129 {
130 	u64 time;
131 	u32 tbtt;
132 
133 	/* Get remaining TBTT in usec */
134 	tbtt = mt76_get_field(dev, MT_TBTT_TIMER, MT_TBTT_TIMER_VAL);
135 	tbtt *= 32;
136 
137 	if (tbtt <= PRE_TBTT_USEC) {
138 		queue_work(system_highpri_wq, &dev->pre_tbtt_work);
139 		return;
140 	}
141 
142 	time = (tbtt - PRE_TBTT_USEC) * 1000ull;
143 	hrtimer_start(&dev->pre_tbtt_timer, time, HRTIMER_MODE_REL);
144 }
145 
mt76x02u_restart_pre_tbtt_timer(struct mt76x02_dev * dev)146 static void mt76x02u_restart_pre_tbtt_timer(struct mt76x02_dev *dev)
147 {
148 	u32 tbtt, dw0, dw1;
149 	u64 tsf, time;
150 
151 	/* Get remaining TBTT in usec */
152 	tbtt = mt76_get_field(dev, MT_TBTT_TIMER, MT_TBTT_TIMER_VAL);
153 	tbtt *= 32;
154 
155 	dw0 = mt76_rr(dev, MT_TSF_TIMER_DW0);
156 	dw1 = mt76_rr(dev, MT_TSF_TIMER_DW1);
157 	tsf = (u64)dw0 << 32 | dw1;
158 	dev_dbg(dev->mt76.dev, "TSF: %llu us TBTT %u us\n", tsf, tbtt);
159 
160 	/* Convert beacon interval in TU (1024 usec) to nsec */
161 	time = ((1000000000ull * dev->mt76.beacon_int) >> 10);
162 
163 	/* Adjust time to trigger hrtimer 8ms before TBTT */
164 	if (tbtt < PRE_TBTT_USEC)
165 		time -= (PRE_TBTT_USEC - tbtt) * 1000ull;
166 	else
167 		time += (tbtt - PRE_TBTT_USEC) * 1000ull;
168 
169 	hrtimer_start(&dev->pre_tbtt_timer, time, HRTIMER_MODE_REL);
170 }
171 
mt76x02u_stop_pre_tbtt_timer(struct mt76x02_dev * dev)172 static void mt76x02u_stop_pre_tbtt_timer(struct mt76x02_dev *dev)
173 {
174 	do {
175 		hrtimer_cancel(&dev->pre_tbtt_timer);
176 		cancel_work_sync(&dev->pre_tbtt_work);
177 		/* Timer can be rearmed by work. */
178 	} while (hrtimer_active(&dev->pre_tbtt_timer));
179 }
180 
mt76x02u_pre_tbtt_work(struct work_struct * work)181 static void mt76x02u_pre_tbtt_work(struct work_struct *work)
182 {
183 	struct mt76x02_dev *dev =
184 		container_of(work, struct mt76x02_dev, pre_tbtt_work);
185 	struct beacon_bc_data data = {};
186 	struct sk_buff *skb;
187 	int nbeacons;
188 
189 	if (!dev->mt76.beacon_mask)
190 		return;
191 
192 	if (mt76_hw(dev)->conf.flags & IEEE80211_CONF_OFFCHANNEL)
193 		return;
194 
195 	mt76x02_resync_beacon_timer(dev);
196 
197 	/* Prevent corrupt transmissions during update */
198 	mt76_set(dev, MT_BCN_BYPASS_MASK, 0xffff);
199 	dev->beacon_data_count = 0;
200 
201 	ieee80211_iterate_active_interfaces(mt76_hw(dev),
202 		IEEE80211_IFACE_ITER_RESUME_ALL,
203 		mt76x02_update_beacon_iter, dev);
204 
205 	mt76_csa_check(&dev->mt76);
206 
207 	if (dev->mt76.csa_complete) {
208 		mt76_csa_finish(&dev->mt76);
209 		goto out;
210 	}
211 
212 	nbeacons = hweight8(dev->mt76.beacon_mask);
213 	mt76x02_enqueue_buffered_bc(dev, &data, N_BCN_SLOTS - nbeacons);
214 
215 	while ((skb = __skb_dequeue(&data.q)) != NULL)
216 		mt76x02_mac_set_beacon(dev, skb);
217 
218 out:
219 	mt76_wr(dev, MT_BCN_BYPASS_MASK,
220 		0xff00 | ~(0xff00 >> dev->beacon_data_count));
221 
222 	mt76x02u_restart_pre_tbtt_timer(dev);
223 }
224 
mt76x02u_pre_tbtt_interrupt(struct hrtimer * timer)225 static enum hrtimer_restart mt76x02u_pre_tbtt_interrupt(struct hrtimer *timer)
226 {
227 	struct mt76x02_dev *dev =
228 	    container_of(timer, struct mt76x02_dev, pre_tbtt_timer);
229 
230 	queue_work(system_highpri_wq, &dev->pre_tbtt_work);
231 
232 	return HRTIMER_NORESTART;
233 }
234 
mt76x02u_pre_tbtt_enable(struct mt76x02_dev * dev,bool en)235 static void mt76x02u_pre_tbtt_enable(struct mt76x02_dev *dev, bool en)
236 {
237 	if (en && dev->mt76.beacon_mask &&
238 	    !hrtimer_active(&dev->pre_tbtt_timer))
239 		mt76x02u_start_pre_tbtt_timer(dev);
240 	if (!en)
241 		mt76x02u_stop_pre_tbtt_timer(dev);
242 }
243 
mt76x02u_beacon_enable(struct mt76x02_dev * dev,bool en)244 static void mt76x02u_beacon_enable(struct mt76x02_dev *dev, bool en)
245 {
246 	if (WARN_ON_ONCE(!dev->mt76.beacon_int))
247 		return;
248 
249 	if (en)
250 		mt76x02u_start_pre_tbtt_timer(dev);
251 }
252 
mt76x02u_init_beacon_config(struct mt76x02_dev * dev)253 void mt76x02u_init_beacon_config(struct mt76x02_dev *dev)
254 {
255 	static const struct mt76x02_beacon_ops beacon_ops = {
256 		.nslots = N_BCN_SLOTS,
257 		.slot_size = (8192 / N_BCN_SLOTS) & ~63,
258 		.pre_tbtt_enable = mt76x02u_pre_tbtt_enable,
259 		.beacon_enable = mt76x02u_beacon_enable,
260 	};
261 	dev->beacon_ops = &beacon_ops;
262 
263 	hrtimer_init(&dev->pre_tbtt_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
264 	dev->pre_tbtt_timer.function = mt76x02u_pre_tbtt_interrupt;
265 	INIT_WORK(&dev->pre_tbtt_work, mt76x02u_pre_tbtt_work);
266 
267 	mt76x02_init_beacon_config(dev);
268 }
269 EXPORT_SYMBOL_GPL(mt76x02u_init_beacon_config);
270 
mt76x02u_exit_beacon_config(struct mt76x02_dev * dev)271 void mt76x02u_exit_beacon_config(struct mt76x02_dev *dev)
272 {
273 	if (!test_bit(MT76_REMOVED, &dev->mphy.state))
274 		mt76_clear(dev, MT_BEACON_TIME_CFG,
275 			   MT_BEACON_TIME_CFG_TIMER_EN |
276 			   MT_BEACON_TIME_CFG_SYNC_MODE |
277 			   MT_BEACON_TIME_CFG_TBTT_EN |
278 			   MT_BEACON_TIME_CFG_BEACON_TX);
279 
280 	mt76x02u_stop_pre_tbtt_timer(dev);
281 }
282 EXPORT_SYMBOL_GPL(mt76x02u_exit_beacon_config);
283