tx.c revision 6f93a8e7e41c2d29749242f983f41e3f6a75b40b
1/**
2  * This file contains the handling of TX in wlan driver.
3  */
4#include <linux/netdevice.h>
5#include <linux/etherdevice.h>
6
7#include "hostcmd.h"
8#include "radiotap.h"
9#include "decl.h"
10#include "defs.h"
11#include "dev.h"
12#include "wext.h"
13
14/**
15 *  @brief This function converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
16 *  units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
17 *
18 *  @param rate    Input rate
19 *  @return      Output Rate (0 if invalid)
20 */
21static u32 convert_radiotap_rate_to_mv(u8 rate)
22{
23	switch (rate) {
24	case 2:		/*   1 Mbps */
25		return 0 | (1 << 4);
26	case 4:		/*   2 Mbps */
27		return 1 | (1 << 4);
28	case 11:		/* 5.5 Mbps */
29		return 2 | (1 << 4);
30	case 22:		/*  11 Mbps */
31		return 3 | (1 << 4);
32	case 12:		/*   6 Mbps */
33		return 4 | (1 << 4);
34	case 18:		/*   9 Mbps */
35		return 5 | (1 << 4);
36	case 24:		/*  12 Mbps */
37		return 6 | (1 << 4);
38	case 36:		/*  18 Mbps */
39		return 7 | (1 << 4);
40	case 48:		/*  24 Mbps */
41		return 8 | (1 << 4);
42	case 72:		/*  36 Mbps */
43		return 9 | (1 << 4);
44	case 96:		/*  48 Mbps */
45		return 10 | (1 << 4);
46	case 108:		/*  54 Mbps */
47		return 11 | (1 << 4);
48	}
49	return 0;
50}
51
52/**
53 *  @brief This function checks the conditions and sends packet to IF
54 *  layer if everything is ok.
55 *
56 *  @param priv    A pointer to struct lbs_private structure
57 *  @param skb     A pointer to skb which includes TX packet
58 *  @return 	   0 or -1
59 */
60int lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
61{
62	unsigned long flags;
63	struct lbs_private *priv = dev->priv;
64	struct txpd *txpd;
65	char *p802x_hdr;
66	uint16_t pkt_len;
67	int ret;
68
69	lbs_deb_enter(LBS_DEB_TX);
70
71	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		priv->stats.tx_dropped++;
86		priv->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 (dev == priv->rtap_net_dev) {
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	if (dev == priv->mesh_dev)
136		txpd->tx_control |= cpu_to_le32(TxPD_MESH_FRAME);
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	priv->stats.tx_packets++;
150	priv->stats.tx_bytes += skb->len;
151
152	dev->trans_start = jiffies;
153
154	if (priv->monitormode != LBS_MONITOR_OFF) {
155		/* Keep the skb to echo it back once Tx feedback is
156		   received from FW */
157		skb_orphan(skb);
158
159		/* Keep the skb around for when we get feedback */
160		priv->currenttxskb = skb;
161	} else {
162 free:
163		dev_kfree_skb_any(skb);
164	}
165 unlock:
166	spin_unlock_irqrestore(&priv->driver_lock, flags);
167	wake_up(&priv->waitq);
168
169	lbs_deb_leave_args(LBS_DEB_TX, "ret %d", ret);
170	return ret;
171}
172
173/**
174 *  @brief This function sends to the host the last transmitted packet,
175 *  filling the radiotap headers with transmission information.
176 *
177 *  @param priv     A pointer to struct lbs_private structure
178 *  @param status   A 32 bit value containing transmission status.
179 *
180 *  @returns void
181 */
182void lbs_send_tx_feedback(struct lbs_private *priv)
183{
184	struct tx_radiotap_hdr *radiotap_hdr;
185	u32 status = priv->eventcause;
186	int txfail;
187	int try_count;
188
189	if (priv->monitormode == LBS_MONITOR_OFF ||
190	    priv->currenttxskb == NULL)
191		return;
192
193	radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
194
195	txfail = (status >> 24);
196
197#if 0
198	/* The version of roofnet that we've tested does not use this yet
199	 * But it may be used in the future.
200	 */
201	if (txfail)
202		radiotap_hdr->flags &= IEEE80211_RADIOTAP_F_TX_FAIL;
203#endif
204	try_count = (status >> 16) & 0xff;
205	radiotap_hdr->data_retries = (try_count) ?
206	    (1 + priv->txretrycount - try_count) : 0;
207
208
209	priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
210						      priv->rtap_net_dev);
211	netif_rx(priv->currenttxskb);
212
213	priv->currenttxskb = NULL;
214
215	if (priv->connect_status == LBS_CONNECTED)
216		netif_wake_queue(priv->dev);
217
218	if (priv->mesh_dev && (priv->mesh_connect_status == LBS_CONNECTED))
219		netif_wake_queue(priv->mesh_dev);
220}
221EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);
222