xref: /linux/drivers/net/wireless/marvell/libertas/tx.c (revision 03ab8e6297acd1bc0eedaa050e2a1635c576fd11)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * This file contains the handling of TX in wlan driver.
4  */
5 #include <linux/hardirq.h>
6 #include <linux/netdevice.h>
7 #include <linux/etherdevice.h>
8 #include <linux/sched.h>
9 #include <linux/export.h>
10 #include <net/cfg80211.h>
11 
12 #include "host.h"
13 #include "radiotap.h"
14 #include "decl.h"
15 #include "defs.h"
16 #include "dev.h"
17 #include "mesh.h"
18 
19 /**
20  * convert_radiotap_rate_to_mv - converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
21  * units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
22  *
23  * @rate:	Input rate
24  * returns:	Output Rate (0 if invalid)
25  */
convert_radiotap_rate_to_mv(u8 rate)26 static u32 convert_radiotap_rate_to_mv(u8 rate)
27 {
28 	switch (rate) {
29 	case 2:		/*   1 Mbps */
30 		return 0 | (1 << 4);
31 	case 4:		/*   2 Mbps */
32 		return 1 | (1 << 4);
33 	case 11:		/* 5.5 Mbps */
34 		return 2 | (1 << 4);
35 	case 22:		/*  11 Mbps */
36 		return 3 | (1 << 4);
37 	case 12:		/*   6 Mbps */
38 		return 4 | (1 << 4);
39 	case 18:		/*   9 Mbps */
40 		return 5 | (1 << 4);
41 	case 24:		/*  12 Mbps */
42 		return 6 | (1 << 4);
43 	case 36:		/*  18 Mbps */
44 		return 7 | (1 << 4);
45 	case 48:		/*  24 Mbps */
46 		return 8 | (1 << 4);
47 	case 72:		/*  36 Mbps */
48 		return 9 | (1 << 4);
49 	case 96:		/*  48 Mbps */
50 		return 10 | (1 << 4);
51 	case 108:		/*  54 Mbps */
52 		return 11 | (1 << 4);
53 	}
54 	return 0;
55 }
56 
57 /**
58  * lbs_hard_start_xmit - checks the conditions and sends packet to IF
59  * layer if everything is ok
60  *
61  * @skb:	A pointer to skb which includes TX packet
62  * @dev:	A pointer to the &struct net_device
63  * returns:	0 or -1
64  */
lbs_hard_start_xmit(struct sk_buff * skb,struct net_device * dev)65 netdev_tx_t lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
66 {
67 	unsigned long flags;
68 	struct lbs_private *priv = dev->ml_priv;
69 	struct txpd *txpd;
70 	char *p802x_hdr;
71 	uint16_t pkt_len;
72 	netdev_tx_t ret = NETDEV_TX_OK;
73 
74 	/* We need to protect against the queues being restarted before
75 	   we get round to stopping them */
76 	spin_lock_irqsave(&priv->driver_lock, flags);
77 
78 	if (priv->surpriseremoved)
79 		goto free;
80 
81 	if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
82 		lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
83 		       skb->len, MRVDRV_ETH_TX_PACKET_BUFFER_SIZE);
84 		/* We'll never manage to send this one; drop it and return 'OK' */
85 
86 		dev->stats.tx_dropped++;
87 		dev->stats.tx_errors++;
88 		goto free;
89 	}
90 
91 
92 	netif_stop_queue(priv->dev);
93 	if (priv->mesh_dev)
94 		netif_stop_queue(priv->mesh_dev);
95 
96 	if (priv->tx_pending_len) {
97 		/* This can happen if packets come in on the mesh and eth
98 		   device simultaneously -- there's no mutual exclusion on
99 		   hard_start_xmit() calls between devices. */
100 		lbs_deb_tx("Packet on %s while busy\n", dev->name);
101 		ret = NETDEV_TX_BUSY;
102 		goto unlock;
103 	}
104 
105 	priv->tx_pending_len = -1;
106 	spin_unlock_irqrestore(&priv->driver_lock, flags);
107 
108 	lbs_deb_hex(LBS_DEB_TX, "TX Data", skb->data, min_t(unsigned int, skb->len, 100));
109 
110 	txpd = (void *)priv->tx_pending_buf;
111 	memset(txpd, 0, sizeof(struct txpd));
112 
113 	p802x_hdr = skb->data;
114 	pkt_len = skb->len;
115 
116 	BUILD_BUG_ON(sizeof(txpd->tx_dest_addr) != ETH_ALEN);
117 	if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
118 		struct tx_radiotap_hdr *rtap_hdr = (void *)skb->data;
119 
120 		/* set txpd fields from the radiotap header */
121 		txpd->tx_control = cpu_to_le32(convert_radiotap_rate_to_mv(rtap_hdr->rate));
122 
123 		/* skip the radiotap header */
124 		p802x_hdr += sizeof(*rtap_hdr);
125 		pkt_len -= sizeof(*rtap_hdr);
126 
127 		/* copy destination address from 802.11 header */
128 		memcpy(&txpd->tx_dest_addr, p802x_hdr + 4, ETH_ALEN);
129 	} else {
130 		/* copy destination address from 802.3 header */
131 		memcpy(&txpd->tx_dest_addr, p802x_hdr, ETH_ALEN);
132 	}
133 
134 	txpd->tx_packet_length = cpu_to_le16(pkt_len);
135 	txpd->tx_packet_location = cpu_to_le32(sizeof(struct txpd));
136 
137 	lbs_mesh_set_txpd(priv, dev, txpd);
138 
139 	lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
140 
141 	lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
142 
143 	memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
144 
145 	spin_lock_irqsave(&priv->driver_lock, flags);
146 	priv->tx_pending_len = pkt_len + sizeof(struct txpd);
147 
148 	lbs_deb_tx("%s lined up packet\n", __func__);
149 
150 	dev->stats.tx_packets++;
151 	dev->stats.tx_bytes += skb->len;
152 
153 	if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
154 		/* Keep the skb to echo it back once Tx feedback is
155 		   received from FW */
156 		skb_orphan(skb);
157 
158 		/* Keep the skb around for when we get feedback */
159 		priv->currenttxskb = skb;
160 	} else {
161  free:
162 		dev_kfree_skb_any(skb);
163 	}
164 
165  unlock:
166 	spin_unlock_irqrestore(&priv->driver_lock, flags);
167 	wake_up(&priv->waitq);
168 
169 	return ret;
170 }
171 
172 /**
173  * lbs_send_tx_feedback - sends to the host the last transmitted packet,
174  * filling the radiotap headers with transmission information.
175  *
176  * @priv:	A pointer to &struct lbs_private structure
177  * @try_count:	A 32-bit value containing transmission retry status.
178  *
179  * returns:	void
180  */
lbs_send_tx_feedback(struct lbs_private * priv,u32 try_count)181 void lbs_send_tx_feedback(struct lbs_private *priv, u32 try_count)
182 {
183 	struct tx_radiotap_hdr *radiotap_hdr;
184 
185 	if (priv->wdev->iftype != NL80211_IFTYPE_MONITOR ||
186 	    priv->currenttxskb == NULL)
187 		return;
188 
189 	radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
190 
191 	radiotap_hdr->data_retries = try_count ?
192 		(1 + priv->txretrycount - try_count) : 0;
193 
194 	priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
195 						      priv->dev);
196 	netif_rx(priv->currenttxskb);
197 
198 	priv->currenttxskb = NULL;
199 
200 	if (priv->connect_status == LBS_CONNECTED)
201 		netif_wake_queue(priv->dev);
202 
203 	if (priv->mesh_dev && netif_running(priv->mesh_dev))
204 		netif_wake_queue(priv->mesh_dev);
205 }
206 EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);
207