1 /*
2  *
3  *  Copyright (C) 2002 Intersil Americas Inc.
4  *  Copyright (C) 2004 Aurelien Alleaume <slts@free.fr>
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License as published by
7  *  the Free Software Foundation; either version 2 of the License
8  *
9  *  This program is distributed in the hope that it will be useful,
10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  *  GNU General Public License for more details.
13  *
14  *  You should have received a copy of the GNU General Public License
15  *  along with this program; if not, write to the Free Software
16  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
17  *
18  */
19 
20 #include <linux/version.h>
21 #include <linux/module.h>
22 
23 #include <linux/pci.h>
24 #include <linux/delay.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/if_arp.h>
28 
29 #include "prismcompat.h"
30 #include "isl_38xx.h"
31 #include "islpci_eth.h"
32 #include "islpci_mgt.h"
33 #include "oid_mgt.h"
34 
35 /******************************************************************************
36     Network Interface functions
37 ******************************************************************************/
38 void
islpci_eth_cleanup_transmit(islpci_private * priv,isl38xx_control_block * control_block)39 islpci_eth_cleanup_transmit(islpci_private *priv,
40 			    isl38xx_control_block *control_block)
41 {
42 	struct sk_buff *skb;
43 	u32 index;
44 
45 	/* compare the control block read pointer with the free pointer */
46 	while (priv->free_data_tx !=
47 	       le32_to_cpu(control_block->
48 			   device_curr_frag[ISL38XX_CB_TX_DATA_LQ])) {
49 		/* read the index of the first fragment to be freed */
50 		index = priv->free_data_tx % ISL38XX_CB_TX_QSIZE;
51 
52 		/* check for holes in the arrays caused by multi fragment frames
53 		 * searching for the last fragment of a frame */
54 		if (priv->pci_map_tx_address[index] != (dma_addr_t) NULL) {
55 			/* entry is the last fragment of a frame
56 			 * free the skb structure and unmap pci memory */
57 			skb = priv->data_low_tx[index];
58 
59 #if VERBOSE > SHOW_ERROR_MESSAGES
60 			DEBUG(SHOW_TRACING,
61 			      "cleanup skb %p skb->data %p skb->len %u truesize %u\n ",
62 			      skb, skb->data, skb->len, skb->truesize);
63 #endif
64 
65 			pci_unmap_single(priv->pdev,
66 					 priv->pci_map_tx_address[index],
67 					 skb->len, PCI_DMA_TODEVICE);
68 			dev_kfree_skb_irq(skb);
69 			skb = NULL;
70 		}
71 		/* increment the free data low queue pointer */
72 		priv->free_data_tx++;
73 	}
74 }
75 
76 int
islpci_eth_transmit(struct sk_buff * skb,struct net_device * ndev)77 islpci_eth_transmit(struct sk_buff *skb, struct net_device *ndev)
78 {
79 	islpci_private *priv = netdev_priv(ndev);
80 	isl38xx_control_block *cb = priv->control_block;
81 	u32 index;
82 	dma_addr_t pci_map_address;
83 	int frame_size;
84 	isl38xx_fragment *fragment;
85 	int offset;
86 	struct sk_buff *newskb;
87 	int newskb_offset;
88 	unsigned long flags;
89 	unsigned char wds_mac[6];
90 	u32 curr_frag;
91 	int err = 0;
92 
93 #if VERBOSE > SHOW_ERROR_MESSAGES
94 	DEBUG(SHOW_FUNCTION_CALLS, "islpci_eth_transmit \n");
95 #endif
96 
97 	/* lock the driver code */
98 	spin_lock_irqsave(&priv->slock, flags);
99 
100 	/* determine the amount of fragments needed to store the frame */
101 
102 	frame_size = skb->len < ETH_ZLEN ? ETH_ZLEN : skb->len;
103 	if (init_wds)
104 		frame_size += 6;
105 
106 	/* check whether the destination queue has enough fragments for the frame */
107 	curr_frag = le32_to_cpu(cb->driver_curr_frag[ISL38XX_CB_TX_DATA_LQ]);
108 	if (unlikely(curr_frag - priv->free_data_tx >= ISL38XX_CB_TX_QSIZE)) {
109 		printk(KERN_ERR "%s: transmit device queue full when awake\n",
110 		       ndev->name);
111 		netif_stop_queue(ndev);
112 
113 		/* trigger the device */
114 		isl38xx_w32_flush(priv->device_base, ISL38XX_DEV_INT_UPDATE,
115 				  ISL38XX_DEV_INT_REG);
116 		udelay(ISL38XX_WRITEIO_DELAY);
117 
118 		err = -EBUSY;
119 		goto drop_free;
120 	}
121 	/* Check alignment and WDS frame formatting. The start of the packet should
122 	 * be aligned on a 4-byte boundary. If WDS is enabled add another 6 bytes
123 	 * and add WDS address information */
124 	if (likely(((long) skb->data & 0x03) | init_wds)) {
125 		/* get the number of bytes to add and re-allign */
126 		offset = (4 - (long) skb->data) & 0x03;
127 		offset += init_wds ? 6 : 0;
128 
129 		/* check whether the current skb can be used  */
130 		if (!skb_cloned(skb) && (skb_tailroom(skb) >= offset)) {
131 			unsigned char *src = skb->data;
132 
133 #if VERBOSE > SHOW_ERROR_MESSAGES
134 			DEBUG(SHOW_TRACING, "skb offset %i wds %i\n", offset,
135 			      init_wds);
136 #endif
137 
138 			/* align the buffer on 4-byte boundary */
139 			skb_reserve(skb, (4 - (long) skb->data) & 0x03);
140 			if (init_wds) {
141 				/* wds requires an additional address field of 6 bytes */
142 				skb_put(skb, 6);
143 #ifdef ISLPCI_ETH_DEBUG
144 				printk("islpci_eth_transmit:wds_mac\n");
145 #endif
146 				memmove(skb->data + 6, src, skb->len);
147 				memcpy(skb->data, wds_mac, 6);
148 			} else {
149 				memmove(skb->data, src, skb->len);
150 			}
151 
152 #if VERBOSE > SHOW_ERROR_MESSAGES
153 			DEBUG(SHOW_TRACING, "memmove %p %p %i \n", skb->data,
154 			      src, skb->len);
155 #endif
156 		} else {
157 			newskb =
158 			    dev_alloc_skb(init_wds ? skb->len + 6 : skb->len);
159 			if (unlikely(newskb == NULL)) {
160 				printk(KERN_ERR "%s: Cannot allocate skb\n",
161 				       ndev->name);
162 				err = -ENOMEM;
163 				goto drop_free;
164 			}
165 			newskb_offset = (4 - (long) newskb->data) & 0x03;
166 
167 			/* Check if newskb->data is aligned */
168 			if (newskb_offset)
169 				skb_reserve(newskb, newskb_offset);
170 
171 			skb_put(newskb, init_wds ? skb->len + 6 : skb->len);
172 			if (init_wds) {
173 				memcpy(newskb->data + 6, skb->data, skb->len);
174 				memcpy(newskb->data, wds_mac, 6);
175 #ifdef ISLPCI_ETH_DEBUG
176 				printk("islpci_eth_transmit:wds_mac\n");
177 #endif
178 			} else
179 				memcpy(newskb->data, skb->data, skb->len);
180 
181 #if VERBOSE > SHOW_ERROR_MESSAGES
182 			DEBUG(SHOW_TRACING, "memcpy %p %p %i wds %i\n",
183 			      newskb->data, skb->data, skb->len, init_wds);
184 #endif
185 
186 			newskb->dev = skb->dev;
187 			dev_kfree_skb(skb);
188 			skb = newskb;
189 		}
190 	}
191 	/* display the buffer contents for debugging */
192 #if VERBOSE > SHOW_ERROR_MESSAGES
193 	DEBUG(SHOW_BUFFER_CONTENTS, "\ntx %p ", skb->data);
194 	display_buffer((char *) skb->data, skb->len);
195 #endif
196 
197 	/* map the skb buffer to pci memory for DMA operation */
198 	pci_map_address = pci_map_single(priv->pdev,
199 					 (void *) skb->data, skb->len,
200 					 PCI_DMA_TODEVICE);
201 	if (unlikely(pci_map_address == 0)) {
202 		printk(KERN_WARNING "%s: cannot map buffer to PCI\n",
203 		       ndev->name);
204 
205 		err = -EIO;
206 		goto drop_free;
207 	}
208 	/* Place the fragment in the control block structure. */
209 	index = curr_frag % ISL38XX_CB_TX_QSIZE;
210 	fragment = &cb->tx_data_low[index];
211 
212 	priv->pci_map_tx_address[index] = pci_map_address;
213 	/* store the skb address for future freeing  */
214 	priv->data_low_tx[index] = skb;
215 	/* set the proper fragment start address and size information */
216 	fragment->size = cpu_to_le16(frame_size);
217 	fragment->flags = cpu_to_le16(0);	/* set to 1 if more fragments */
218 	fragment->address = cpu_to_le32(pci_map_address);
219 	curr_frag++;
220 
221 	/* The fragment address in the control block must have been
222 	 * written before announcing the frame buffer to device. */
223 	wmb();
224 	cb->driver_curr_frag[ISL38XX_CB_TX_DATA_LQ] = cpu_to_le32(curr_frag);
225 
226 	if (curr_frag - priv->free_data_tx + ISL38XX_MIN_QTHRESHOLD
227 	    > ISL38XX_CB_TX_QSIZE) {
228 		/* stop sends from upper layers */
229 		netif_stop_queue(ndev);
230 
231 		/* set the full flag for the transmission queue */
232 		priv->data_low_tx_full = 1;
233 	}
234 
235 	/* trigger the device */
236 	islpci_trigger(priv);
237 
238 	/* unlock the driver code */
239 	spin_unlock_irqrestore(&priv->slock, flags);
240 
241 	/* set the transmission time */
242 	ndev->trans_start = jiffies;
243 	priv->statistics.tx_packets++;
244 	priv->statistics.tx_bytes += skb->len;
245 
246 	return 0;
247 
248       drop_free:
249 	/* free the skbuf structure before aborting */
250 	dev_kfree_skb(skb);
251 	skb = NULL;
252 
253 	priv->statistics.tx_dropped++;
254 	spin_unlock_irqrestore(&priv->slock, flags);
255 	return err;
256 }
257 
258 static inline int
islpci_monitor_rx(islpci_private * priv,struct sk_buff ** skb)259 islpci_monitor_rx(islpci_private *priv, struct sk_buff **skb)
260 {
261 	/* The card reports full 802.11 packets but with a 20 bytes
262 	 * header and without the FCS. But there a is a bit that
263 	 * indicates if the packet is corrupted :-) */
264 	struct rfmon_header *hdr = (struct rfmon_header *) (*skb)->data;
265 	if (hdr->flags & 0x01)
266 		/* This one is bad. Drop it ! */
267 		return -1;
268 	if (priv->ndev->type == ARPHRD_IEEE80211_PRISM) {
269 		struct avs_80211_1_header *avs;
270 		/* extract the relevant data from the header */
271 		u32 clock = le32_to_cpu(hdr->clock);
272 		u8 rate = hdr->rate;
273 		u16 freq = le16_to_cpu(hdr->freq);
274 		u8 rssi = hdr->rssi;
275 
276 		skb_pull(*skb, sizeof (struct rfmon_header));
277 
278 		if (skb_headroom(*skb) < sizeof (struct avs_80211_1_header)) {
279 			struct sk_buff *newskb = skb_copy_expand(*skb,
280 								 sizeof (struct
281 									 avs_80211_1_header),
282 								 0, GFP_ATOMIC);
283 			if (newskb) {
284 				dev_kfree_skb_irq(*skb);
285 				*skb = newskb;
286 			} else
287 				return -1;
288 			/* This behavior is not very subtile... */
289 		}
290 
291 		/* make room for the new header and fill it. */
292 		avs =
293 		    (struct avs_80211_1_header *) skb_push(*skb,
294 							   sizeof (struct
295 								   avs_80211_1_header));
296 
297 		avs->version = cpu_to_be32(P80211CAPTURE_VERSION);
298 		avs->length = cpu_to_be32(sizeof (struct avs_80211_1_header));
299 		avs->mactime = cpu_to_be64(le64_to_cpu(clock));
300 		avs->hosttime = cpu_to_be64(jiffies);
301 		avs->phytype = cpu_to_be32(6);	/*OFDM: 6 for (g), 8 for (a) */
302 		avs->channel = cpu_to_be32(channel_of_freq(freq));
303 		avs->datarate = cpu_to_be32(rate * 5);
304 		avs->antenna = cpu_to_be32(0);	/*unknown */
305 		avs->priority = cpu_to_be32(0);	/*unknown */
306 		avs->ssi_type = cpu_to_be32(3);	/*2: dBm, 3: raw RSSI */
307 		avs->ssi_signal = cpu_to_be32(rssi & 0x7f);
308 		avs->ssi_noise = cpu_to_be32(priv->local_iwstatistics.qual.noise);	/*better than 'undefined', I assume */
309 		avs->preamble = cpu_to_be32(0);	/*unknown */
310 		avs->encoding = cpu_to_be32(0);	/*unknown */
311 	} else
312 		skb_pull(*skb, sizeof (struct rfmon_header));
313 
314 	(*skb)->protocol = htons(ETH_P_802_2);
315 	(*skb)->mac.raw = (*skb)->data;
316 	(*skb)->pkt_type = PACKET_OTHERHOST;
317 
318 	return 0;
319 }
320 
321 int
islpci_eth_receive(islpci_private * priv)322 islpci_eth_receive(islpci_private *priv)
323 {
324 	struct net_device *ndev = priv->ndev;
325 	isl38xx_control_block *control_block = priv->control_block;
326 	struct sk_buff *skb;
327 	u16 size;
328 	u32 index, offset;
329 	unsigned char *src;
330 	int discard = 0;
331 
332 #if VERBOSE > SHOW_ERROR_MESSAGES
333 	DEBUG(SHOW_FUNCTION_CALLS, "islpci_eth_receive \n");
334 #endif
335 
336 	/* the device has written an Ethernet frame in the data area
337 	 * of the sk_buff without updating the structure, do it now */
338 	index = priv->free_data_rx % ISL38XX_CB_RX_QSIZE;
339 	size = le16_to_cpu(control_block->rx_data_low[index].size);
340 	skb = priv->data_low_rx[index];
341 	offset = ((unsigned long)
342 		  le32_to_cpu(control_block->rx_data_low[index].address) -
343 		  (unsigned long) skb->data) & 3;
344 
345 #if VERBOSE > SHOW_ERROR_MESSAGES
346 	DEBUG(SHOW_TRACING,
347 	      "frq->addr %x skb->data %p skb->len %u offset %u truesize %u\n ",
348 	      control_block->rx_data_low[priv->free_data_rx].address, skb->data,
349 	      skb->len, offset, skb->truesize);
350 #endif
351 
352 	/* delete the streaming DMA mapping before processing the skb */
353 	pci_unmap_single(priv->pdev,
354 			 priv->pci_map_rx_address[index],
355 			 MAX_FRAGMENT_SIZE_RX + 2, PCI_DMA_FROMDEVICE);
356 
357 	/* update the skb structure and allign the buffer */
358 	skb_put(skb, size);
359 	if (offset) {
360 		/* shift the buffer allocation offset bytes to get the right frame */
361 		skb_pull(skb, 2);
362 		skb_put(skb, 2);
363 	}
364 #if VERBOSE > SHOW_ERROR_MESSAGES
365 	/* display the buffer contents for debugging */
366 	DEBUG(SHOW_BUFFER_CONTENTS, "\nrx %p ", skb->data);
367 	display_buffer((char *) skb->data, skb->len);
368 #endif
369 
370 	/* check whether WDS is enabled and whether the data frame is a WDS frame */
371 
372 	if (init_wds) {
373 		/* WDS enabled, check for the wds address on the first 6 bytes of the buffer */
374 		src = skb->data + 6;
375 		memmove(skb->data, src, skb->len - 6);
376 		skb_trim(skb, skb->len - 6);
377 	}
378 #if VERBOSE > SHOW_ERROR_MESSAGES
379 	DEBUG(SHOW_TRACING, "Fragment size %i in skb at %p\n", size, skb);
380 	DEBUG(SHOW_TRACING, "Skb data at %p, length %i\n", skb->data, skb->len);
381 
382 	/* display the buffer contents for debugging */
383 	DEBUG(SHOW_BUFFER_CONTENTS, "\nrx %p ", skb->data);
384 	display_buffer((char *) skb->data, skb->len);
385 #endif
386 
387 	/* do some additional sk_buff and network layer parameters */
388 	skb->dev = ndev;
389 
390 	/* take care of monitor mode and spy monitoring. */
391 	if (unlikely(priv->iw_mode == IW_MODE_MONITOR))
392 		discard = islpci_monitor_rx(priv, &skb);
393 	else {
394 		if (unlikely(skb->data[2 * ETH_ALEN] == 0)) {
395 			/* The packet has a rx_annex. Read it for spy monitoring, Then
396 			 * remove it, while keeping the 2 leading MAC addr.
397 			 */
398 			struct iw_quality wstats;
399 			struct rx_annex_header *annex =
400 			    (struct rx_annex_header *) skb->data;
401 			wstats.level = annex->rfmon.rssi;
402 			/* The noise value can be a bit outdated if nobody's
403 			 * reading wireless stats... */
404 			wstats.noise = priv->local_iwstatistics.qual.noise;
405 			wstats.qual = wstats.level - wstats.noise;
406 			wstats.updated = 0x07;
407 			/* Update spy records */
408 			wireless_spy_update(ndev, annex->addr2, &wstats);
409 
410 			memcpy(skb->data + sizeof (struct rfmon_header),
411 			       skb->data, 2 * ETH_ALEN);
412 			skb_pull(skb, sizeof (struct rfmon_header));
413 		}
414 		skb->protocol = eth_type_trans(skb, ndev);
415 	}
416 	skb->ip_summed = CHECKSUM_NONE;
417 	priv->statistics.rx_packets++;
418 	priv->statistics.rx_bytes += size;
419 
420 	/* deliver the skb to the network layer */
421 #ifdef ISLPCI_ETH_DEBUG
422 	printk
423 	    ("islpci_eth_receive:netif_rx %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
424 	     skb->data[0], skb->data[1], skb->data[2], skb->data[3],
425 	     skb->data[4], skb->data[5]);
426 #endif
427 	if (unlikely(discard)) {
428 		dev_kfree_skb_irq(skb);
429 		skb = NULL;
430 	} else
431 		netif_rx(skb);
432 
433 	/* increment the read index for the rx data low queue */
434 	priv->free_data_rx++;
435 
436 	/* add one or more sk_buff structures */
437 	while (index =
438 	       le32_to_cpu(control_block->
439 			   driver_curr_frag[ISL38XX_CB_RX_DATA_LQ]),
440 	       index - priv->free_data_rx < ISL38XX_CB_RX_QSIZE) {
441 		/* allocate an sk_buff for received data frames storage
442 		 * include any required allignment operations */
443 		skb = dev_alloc_skb(MAX_FRAGMENT_SIZE_RX + 2);
444 		if (unlikely(skb == NULL)) {
445 			/* error allocating an sk_buff structure elements */
446 			DEBUG(SHOW_ERROR_MESSAGES, "Error allocating skb \n");
447 			break;
448 		}
449 		skb_reserve(skb, (4 - (long) skb->data) & 0x03);
450 		/* store the new skb structure pointer */
451 		index = index % ISL38XX_CB_RX_QSIZE;
452 		priv->data_low_rx[index] = skb;
453 
454 #if VERBOSE > SHOW_ERROR_MESSAGES
455 		DEBUG(SHOW_TRACING,
456 		      "new alloc skb %p skb->data %p skb->len %u index %u truesize %u\n ",
457 		      skb, skb->data, skb->len, index, skb->truesize);
458 #endif
459 
460 		/* set the streaming DMA mapping for proper PCI bus operation */
461 		priv->pci_map_rx_address[index] =
462 		    pci_map_single(priv->pdev, (void *) skb->data,
463 				   MAX_FRAGMENT_SIZE_RX + 2,
464 				   PCI_DMA_FROMDEVICE);
465 		if (unlikely(priv->pci_map_rx_address[index] == (dma_addr_t) NULL)) {
466 			/* error mapping the buffer to device accessable memory address */
467 			DEBUG(SHOW_ERROR_MESSAGES,
468 			      "Error mapping DMA address\n");
469 
470 			/* free the skbuf structure before aborting */
471 			dev_kfree_skb_irq((struct sk_buff *) skb);
472 			skb = NULL;
473 			break;
474 		}
475 		/* update the fragment address */
476 		control_block->rx_data_low[index].address = cpu_to_le32((u32)
477 									priv->
478 									pci_map_rx_address
479 									[index]);
480 		wmb();
481 
482 		/* increment the driver read pointer */
483 		add_le32p((u32 *) &control_block->
484 			  driver_curr_frag[ISL38XX_CB_RX_DATA_LQ], 1);
485 	}
486 
487 	/* trigger the device */
488 	islpci_trigger(priv);
489 
490 	return 0;
491 }
492 
493 void
islpci_do_reset_and_wake(void * data)494 islpci_do_reset_and_wake(void *data)
495 {
496 	islpci_private *priv = (islpci_private *) data;
497 	islpci_reset(priv, 1);
498 	netif_wake_queue(priv->ndev);
499 	priv->reset_task_pending = 0;
500 }
501 
502 void
islpci_eth_tx_timeout(struct net_device * ndev)503 islpci_eth_tx_timeout(struct net_device *ndev)
504 {
505 	islpci_private *priv = netdev_priv(ndev);
506 	struct net_device_stats *statistics = &priv->statistics;
507 
508 	/* increment the transmit error counter */
509 	statistics->tx_errors++;
510 
511 	printk(KERN_WARNING "%s: tx_timeout", ndev->name);
512 	if (!priv->reset_task_pending) {
513 		priv->reset_task_pending = 1;
514 		printk(", scheduling a reset");
515 		netif_stop_queue(ndev);
516 		schedule_work(&priv->reset_task);
517 	}
518 	printk("\n");
519 }
520