xref: /linux/drivers/net/wireless/marvell/libertas/tx.c (revision 64282ea2d2a90437c0739ce016b80a1dec16507e)
1 /*
2  * This file contains the handling of TX in wlan driver.
3  */
4 #include <linux/hardirq.h>
5 #include <linux/netdevice.h>
6 #include <linux/etherdevice.h>
7 #include <linux/sched.h>
8 #include <linux/export.h>
9 #include <net/cfg80211.h>
10 
11 #include "host.h"
12 #include "radiotap.h"
13 #include "decl.h"
14 #include "defs.h"
15 #include "dev.h"
16 #include "mesh.h"
17 
18 /**
19  * convert_radiotap_rate_to_mv - converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
20  * units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
21  *
22  * @rate:	Input rate
23  * returns:	Output Rate (0 if invalid)
24  */
25 static u32 convert_radiotap_rate_to_mv(u8 rate)
26 {
27 	switch (rate) {
28 	case 2:		/*   1 Mbps */
29 		return 0 | (1 << 4);
30 	case 4:		/*   2 Mbps */
31 		return 1 | (1 << 4);
32 	case 11:		/* 5.5 Mbps */
33 		return 2 | (1 << 4);
34 	case 22:		/*  11 Mbps */
35 		return 3 | (1 << 4);
36 	case 12:		/*   6 Mbps */
37 		return 4 | (1 << 4);
38 	case 18:		/*   9 Mbps */
39 		return 5 | (1 << 4);
40 	case 24:		/*  12 Mbps */
41 		return 6 | (1 << 4);
42 	case 36:		/*  18 Mbps */
43 		return 7 | (1 << 4);
44 	case 48:		/*  24 Mbps */
45 		return 8 | (1 << 4);
46 	case 72:		/*  36 Mbps */
47 		return 9 | (1 << 4);
48 	case 96:		/*  48 Mbps */
49 		return 10 | (1 << 4);
50 	case 108:		/*  54 Mbps */
51 		return 11 | (1 << 4);
52 	}
53 	return 0;
54 }
55 
56 /**
57  * lbs_hard_start_xmit - checks the conditions and sends packet to IF
58  * layer if everything is ok
59  *
60  * @skb:	A pointer to skb which includes TX packet
61  * @dev:	A pointer to the &struct net_device
62  * returns:	0 or -1
63  */
64 netdev_tx_t lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
65 {
66 	unsigned long flags;
67 	struct lbs_private *priv = dev->ml_priv;
68 	struct txpd *txpd;
69 	char *p802x_hdr;
70 	uint16_t pkt_len;
71 	netdev_tx_t ret = NETDEV_TX_OK;
72 
73 	/* We need to protect against the queues being restarted before
74 	   we get round to stopping them */
75 	spin_lock_irqsave(&priv->driver_lock, flags);
76 
77 	if (priv->surpriseremoved)
78 		goto free;
79 
80 	if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
81 		lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
82 		       skb->len, MRVDRV_ETH_TX_PACKET_BUFFER_SIZE);
83 		/* We'll never manage to send this one; drop it and return 'OK' */
84 
85 		dev->stats.tx_dropped++;
86 		dev->stats.tx_errors++;
87 		goto free;
88 	}
89 
90 
91 	netif_stop_queue(priv->dev);
92 	if (priv->mesh_dev)
93 		netif_stop_queue(priv->mesh_dev);
94 
95 	if (priv->tx_pending_len) {
96 		/* This can happen if packets come in on the mesh and eth
97 		   device simultaneously -- there's no mutual exclusion on
98 		   hard_start_xmit() calls between devices. */
99 		lbs_deb_tx("Packet on %s while busy\n", dev->name);
100 		ret = NETDEV_TX_BUSY;
101 		goto unlock;
102 	}
103 
104 	priv->tx_pending_len = -1;
105 	spin_unlock_irqrestore(&priv->driver_lock, flags);
106 
107 	lbs_deb_hex(LBS_DEB_TX, "TX Data", skb->data, min_t(unsigned int, skb->len, 100));
108 
109 	txpd = (void *)priv->tx_pending_buf;
110 	memset(txpd, 0, sizeof(struct txpd));
111 
112 	p802x_hdr = skb->data;
113 	pkt_len = skb->len;
114 
115 	if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
116 		struct tx_radiotap_hdr *rtap_hdr = (void *)skb->data;
117 
118 		/* set txpd fields from the radiotap header */
119 		txpd->tx_control = cpu_to_le32(convert_radiotap_rate_to_mv(rtap_hdr->rate));
120 
121 		/* skip the radiotap header */
122 		p802x_hdr += sizeof(*rtap_hdr);
123 		pkt_len -= sizeof(*rtap_hdr);
124 
125 		/* copy destination address from 802.11 header */
126 		memcpy(txpd->tx_dest_addr_high, p802x_hdr + 4, ETH_ALEN);
127 	} else {
128 		/* copy destination address from 802.3 header */
129 		memcpy(txpd->tx_dest_addr_high, p802x_hdr, ETH_ALEN);
130 	}
131 
132 	txpd->tx_packet_length = cpu_to_le16(pkt_len);
133 	txpd->tx_packet_location = cpu_to_le32(sizeof(struct txpd));
134 
135 	lbs_mesh_set_txpd(priv, dev, txpd);
136 
137 	lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
138 
139 	lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
140 
141 	memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
142 
143 	spin_lock_irqsave(&priv->driver_lock, flags);
144 	priv->tx_pending_len = pkt_len + sizeof(struct txpd);
145 
146 	lbs_deb_tx("%s lined up packet\n", __func__);
147 
148 	dev->stats.tx_packets++;
149 	dev->stats.tx_bytes += skb->len;
150 
151 	if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
152 		/* Keep the skb to echo it back once Tx feedback is
153 		   received from FW */
154 		skb_orphan(skb);
155 
156 		/* Keep the skb around for when we get feedback */
157 		priv->currenttxskb = skb;
158 	} else {
159  free:
160 		dev_kfree_skb_any(skb);
161 	}
162 
163  unlock:
164 	spin_unlock_irqrestore(&priv->driver_lock, flags);
165 	wake_up(&priv->waitq);
166 
167 	return ret;
168 }
169 
170 /**
171  * lbs_send_tx_feedback - sends to the host the last transmitted packet,
172  * filling the radiotap headers with transmission information.
173  *
174  * @priv:	A pointer to &struct lbs_private structure
175  * @try_count:	A 32-bit value containing transmission retry status.
176  *
177  * returns:	void
178  */
179 void lbs_send_tx_feedback(struct lbs_private *priv, u32 try_count)
180 {
181 	struct tx_radiotap_hdr *radiotap_hdr;
182 
183 	if (priv->wdev->iftype != NL80211_IFTYPE_MONITOR ||
184 	    priv->currenttxskb == NULL)
185 		return;
186 
187 	radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
188 
189 	radiotap_hdr->data_retries = try_count ?
190 		(1 + priv->txretrycount - try_count) : 0;
191 
192 	priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
193 						      priv->dev);
194 	netif_rx(priv->currenttxskb);
195 
196 	priv->currenttxskb = NULL;
197 
198 	if (priv->connect_status == LBS_CONNECTED)
199 		netif_wake_queue(priv->dev);
200 
201 	if (priv->mesh_dev && netif_running(priv->mesh_dev))
202 		netif_wake_queue(priv->mesh_dev);
203 }
204 EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);
205