tx.c revision 49fee69204035247fd2a5828863fc6f633e829f2
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 <net/cfg80211.h>
9
10#include "host.h"
11#include "radiotap.h"
12#include "decl.h"
13#include "defs.h"
14#include "dev.h"
15#include "mesh.h"
16
17/**
18 * convert_radiotap_rate_to_mv - converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
19 * units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
20 *
21 * @rate:	Input rate
22 * returns:	Output Rate (0 if invalid)
23 */
24static u32 convert_radiotap_rate_to_mv(u8 rate)
25{
26	switch (rate) {
27	case 2:		/*   1 Mbps */
28		return 0 | (1 << 4);
29	case 4:		/*   2 Mbps */
30		return 1 | (1 << 4);
31	case 11:		/* 5.5 Mbps */
32		return 2 | (1 << 4);
33	case 22:		/*  11 Mbps */
34		return 3 | (1 << 4);
35	case 12:		/*   6 Mbps */
36		return 4 | (1 << 4);
37	case 18:		/*   9 Mbps */
38		return 5 | (1 << 4);
39	case 24:		/*  12 Mbps */
40		return 6 | (1 << 4);
41	case 36:		/*  18 Mbps */
42		return 7 | (1 << 4);
43	case 48:		/*  24 Mbps */
44		return 8 | (1 << 4);
45	case 72:		/*  36 Mbps */
46		return 9 | (1 << 4);
47	case 96:		/*  48 Mbps */
48		return 10 | (1 << 4);
49	case 108:		/*  54 Mbps */
50		return 11 | (1 << 4);
51	}
52	return 0;
53}
54
55/**
56 * lbs_hard_start_xmit - checks the conditions and sends packet to IF
57 * layer if everything is ok
58 *
59 * @skb:	A pointer to skb which includes TX packet
60 * @dev:	A pointer to the &struct net_device
61 * returns:	0 or -1
62 */
63netdev_tx_t lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
64{
65	unsigned long flags;
66	struct lbs_private *priv = dev->ml_priv;
67	struct txpd *txpd;
68	char *p802x_hdr;
69	uint16_t pkt_len;
70	netdev_tx_t ret = NETDEV_TX_OK;
71
72	lbs_deb_enter(LBS_DEB_TX);
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	if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
117		struct tx_radiotap_hdr *rtap_hdr = (void *)skb->data;
118
119		/* set txpd fields from the radiotap header */
120		txpd->tx_control = cpu_to_le32(convert_radiotap_rate_to_mv(rtap_hdr->rate));
121
122		/* skip the radiotap header */
123		p802x_hdr += sizeof(*rtap_hdr);
124		pkt_len -= sizeof(*rtap_hdr);
125
126		/* copy destination address from 802.11 header */
127		memcpy(txpd->tx_dest_addr_high, p802x_hdr + 4, ETH_ALEN);
128	} else {
129		/* copy destination address from 802.3 header */
130		memcpy(txpd->tx_dest_addr_high, p802x_hdr, ETH_ALEN);
131	}
132
133	txpd->tx_packet_length = cpu_to_le16(pkt_len);
134	txpd->tx_packet_location = cpu_to_le32(sizeof(struct txpd));
135
136	lbs_mesh_set_txpd(priv, dev, txpd);
137
138	lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
139
140	lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
141
142	memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
143
144	spin_lock_irqsave(&priv->driver_lock, flags);
145	priv->tx_pending_len = pkt_len + sizeof(struct txpd);
146
147	lbs_deb_tx("%s lined up packet\n", __func__);
148
149	dev->stats.tx_packets++;
150	dev->stats.tx_bytes += skb->len;
151
152	if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
153		/* Keep the skb to echo it back once Tx feedback is
154		   received from FW */
155		skb_orphan(skb);
156
157		/* Keep the skb around for when we get feedback */
158		priv->currenttxskb = skb;
159	} else {
160 free:
161		dev_kfree_skb_any(skb);
162	}
163
164 unlock:
165	spin_unlock_irqrestore(&priv->driver_lock, flags);
166	wake_up(&priv->waitq);
167
168	lbs_deb_leave_args(LBS_DEB_TX, "ret %d", ret);
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 */
181void 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}
206EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);
207