1 /*
2  *  Copyright (C) 2002 Intersil Americas Inc.
3  *  Copyright (C) 2004 Aurelien Alleaume <slts@free.fr>
4  *  This program is free software; you can redistribute it and/or modify
5  *  it under the terms of the GNU General Public License as published by
6  *  the Free Software Foundation; either version 2 of the License
7  *
8  *  This program is distributed in the hope that it will be useful,
9  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
10  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  *  GNU General Public License for more details.
12  *
13  *  You should have received a copy of the GNU General Public License
14  *  along with this program; if not, write to the Free Software
15  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
16  *
17  */
18 
19 #include <linux/module.h>
20 #include <linux/gfp.h>
21 
22 #include <linux/pci.h>
23 #include <linux/delay.h>
24 #include <linux/netdevice.h>
25 #include <linux/etherdevice.h>
26 #include <linux/if_arp.h>
27 #include <asm/byteorder.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]) {
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 netdev_tx_t
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 
92 #if VERBOSE > SHOW_ERROR_MESSAGES
93 	DEBUG(SHOW_FUNCTION_CALLS, "islpci_eth_transmit\n");
94 #endif
95 
96 	/* lock the driver code */
97 	spin_lock_irqsave(&priv->slock, flags);
98 
99 	/* check whether the destination queue has enough fragments for the frame */
100 	curr_frag = le32_to_cpu(cb->driver_curr_frag[ISL38XX_CB_TX_DATA_LQ]);
101 	if (unlikely(curr_frag - priv->free_data_tx >= ISL38XX_CB_TX_QSIZE)) {
102 		printk(KERN_ERR "%s: transmit device queue full when awake\n",
103 		       ndev->name);
104 		netif_stop_queue(ndev);
105 
106 		/* trigger the device */
107 		isl38xx_w32_flush(priv->device_base, ISL38XX_DEV_INT_UPDATE,
108 				  ISL38XX_DEV_INT_REG);
109 		udelay(ISL38XX_WRITEIO_DELAY);
110 		goto drop_free;
111 	}
112 	/* Check alignment and WDS frame formatting. The start of the packet should
113 	 * be aligned on a 4-byte boundary. If WDS is enabled add another 6 bytes
114 	 * and add WDS address information */
115 	if (likely(((long) skb->data & 0x03) | init_wds)) {
116 		/* get the number of bytes to add and re-align */
117 		offset = (4 - (long) skb->data) & 0x03;
118 		offset += init_wds ? 6 : 0;
119 
120 		/* check whether the current skb can be used  */
121 		if (!skb_cloned(skb) && (skb_tailroom(skb) >= offset)) {
122 			unsigned char *src = skb->data;
123 
124 #if VERBOSE > SHOW_ERROR_MESSAGES
125 			DEBUG(SHOW_TRACING, "skb offset %i wds %i\n", offset,
126 			      init_wds);
127 #endif
128 
129 			/* align the buffer on 4-byte boundary */
130 			skb_reserve(skb, (4 - (long) skb->data) & 0x03);
131 			if (init_wds) {
132 				/* wds requires an additional address field of 6 bytes */
133 				skb_put(skb, 6);
134 #ifdef ISLPCI_ETH_DEBUG
135 				printk("islpci_eth_transmit:wds_mac\n");
136 #endif
137 				memmove(skb->data + 6, src, skb->len);
138 				skb_copy_to_linear_data(skb, wds_mac, 6);
139 			} else {
140 				memmove(skb->data, src, skb->len);
141 			}
142 
143 #if VERBOSE > SHOW_ERROR_MESSAGES
144 			DEBUG(SHOW_TRACING, "memmove %p %p %i\n", skb->data,
145 			      src, skb->len);
146 #endif
147 		} else {
148 			newskb =
149 			    dev_alloc_skb(init_wds ? skb->len + 6 : skb->len);
150 			if (unlikely(newskb == NULL)) {
151 				printk(KERN_ERR "%s: Cannot allocate skb\n",
152 				       ndev->name);
153 				goto drop_free;
154 			}
155 			newskb_offset = (4 - (long) newskb->data) & 0x03;
156 
157 			/* Check if newskb->data is aligned */
158 			if (newskb_offset)
159 				skb_reserve(newskb, newskb_offset);
160 
161 			skb_put(newskb, init_wds ? skb->len + 6 : skb->len);
162 			if (init_wds) {
163 				skb_copy_from_linear_data(skb,
164 							  newskb->data + 6,
165 							  skb->len);
166 				skb_copy_to_linear_data(newskb, wds_mac, 6);
167 #ifdef ISLPCI_ETH_DEBUG
168 				printk("islpci_eth_transmit:wds_mac\n");
169 #endif
170 			} else
171 				skb_copy_from_linear_data(skb, newskb->data,
172 							  skb->len);
173 
174 #if VERBOSE > SHOW_ERROR_MESSAGES
175 			DEBUG(SHOW_TRACING, "memcpy %p %p %i wds %i\n",
176 			      newskb->data, skb->data, skb->len, init_wds);
177 #endif
178 
179 			newskb->dev = skb->dev;
180 			dev_kfree_skb_irq(skb);
181 			skb = newskb;
182 		}
183 	}
184 	/* display the buffer contents for debugging */
185 #if VERBOSE > SHOW_ERROR_MESSAGES
186 	DEBUG(SHOW_BUFFER_CONTENTS, "\ntx %p ", skb->data);
187 	display_buffer((char *) skb->data, skb->len);
188 #endif
189 
190 	/* map the skb buffer to pci memory for DMA operation */
191 	pci_map_address = pci_map_single(priv->pdev,
192 					 (void *) skb->data, skb->len,
193 					 PCI_DMA_TODEVICE);
194 	if (unlikely(pci_map_address == 0)) {
195 		printk(KERN_WARNING "%s: cannot map buffer to PCI\n",
196 		       ndev->name);
197 		goto drop_free;
198 	}
199 	/* Place the fragment in the control block structure. */
200 	index = curr_frag % ISL38XX_CB_TX_QSIZE;
201 	fragment = &cb->tx_data_low[index];
202 
203 	priv->pci_map_tx_address[index] = pci_map_address;
204 	/* store the skb address for future freeing  */
205 	priv->data_low_tx[index] = skb;
206 	/* set the proper fragment start address and size information */
207 	frame_size = skb->len;
208 	fragment->size = cpu_to_le16(frame_size);
209 	fragment->flags = cpu_to_le16(0);	/* set to 1 if more fragments */
210 	fragment->address = cpu_to_le32(pci_map_address);
211 	curr_frag++;
212 
213 	/* The fragment address in the control block must have been
214 	 * written before announcing the frame buffer to device. */
215 	wmb();
216 	cb->driver_curr_frag[ISL38XX_CB_TX_DATA_LQ] = cpu_to_le32(curr_frag);
217 
218 	if (curr_frag - priv->free_data_tx + ISL38XX_MIN_QTHRESHOLD
219 	    > ISL38XX_CB_TX_QSIZE) {
220 		/* stop sends from upper layers */
221 		netif_stop_queue(ndev);
222 
223 		/* set the full flag for the transmission queue */
224 		priv->data_low_tx_full = 1;
225 	}
226 
227 	ndev->stats.tx_packets++;
228 	ndev->stats.tx_bytes += skb->len;
229 
230 	/* trigger the device */
231 	islpci_trigger(priv);
232 
233 	/* unlock the driver code */
234 	spin_unlock_irqrestore(&priv->slock, flags);
235 
236 	return NETDEV_TX_OK;
237 
238       drop_free:
239 	ndev->stats.tx_dropped++;
240 	spin_unlock_irqrestore(&priv->slock, flags);
241 	dev_kfree_skb(skb);
242 	return NETDEV_TX_OK;
243 }
244 
245 static inline int
islpci_monitor_rx(islpci_private * priv,struct sk_buff ** skb)246 islpci_monitor_rx(islpci_private *priv, struct sk_buff **skb)
247 {
248 	/* The card reports full 802.11 packets but with a 20 bytes
249 	 * header and without the FCS. But there a is a bit that
250 	 * indicates if the packet is corrupted :-) */
251 	struct rfmon_header *hdr = (struct rfmon_header *) (*skb)->data;
252 
253 	if (hdr->flags & 0x01)
254 		/* This one is bad. Drop it ! */
255 		return -1;
256 	if (priv->ndev->type == ARPHRD_IEEE80211_PRISM) {
257 		struct avs_80211_1_header *avs;
258 		/* extract the relevant data from the header */
259 		u32 clock = le32_to_cpu(hdr->clock);
260 		u8 rate = hdr->rate;
261 		u16 freq = le16_to_cpu(hdr->freq);
262 		u8 rssi = hdr->rssi;
263 
264 		skb_pull(*skb, sizeof (struct rfmon_header));
265 
266 		if (skb_headroom(*skb) < sizeof (struct avs_80211_1_header)) {
267 			struct sk_buff *newskb = skb_copy_expand(*skb,
268 								 sizeof (struct
269 									 avs_80211_1_header),
270 								 0, GFP_ATOMIC);
271 			if (newskb) {
272 				dev_kfree_skb_irq(*skb);
273 				*skb = newskb;
274 			} else
275 				return -1;
276 			/* This behavior is not very subtile... */
277 		}
278 
279 		/* make room for the new header and fill it. */
280 		avs =
281 		    (struct avs_80211_1_header *) skb_push(*skb,
282 							   sizeof (struct
283 								   avs_80211_1_header));
284 
285 		avs->version = cpu_to_be32(P80211CAPTURE_VERSION);
286 		avs->length = cpu_to_be32(sizeof (struct avs_80211_1_header));
287 		avs->mactime = cpu_to_be64(clock);
288 		avs->hosttime = cpu_to_be64(jiffies);
289 		avs->phytype = cpu_to_be32(6);	/*OFDM: 6 for (g), 8 for (a) */
290 		avs->channel = cpu_to_be32(channel_of_freq(freq));
291 		avs->datarate = cpu_to_be32(rate * 5);
292 		avs->antenna = cpu_to_be32(0);	/*unknown */
293 		avs->priority = cpu_to_be32(0);	/*unknown */
294 		avs->ssi_type = cpu_to_be32(3);	/*2: dBm, 3: raw RSSI */
295 		avs->ssi_signal = cpu_to_be32(rssi & 0x7f);
296 		avs->ssi_noise = cpu_to_be32(priv->local_iwstatistics.qual.noise);	/*better than 'undefined', I assume */
297 		avs->preamble = cpu_to_be32(0);	/*unknown */
298 		avs->encoding = cpu_to_be32(0);	/*unknown */
299 	} else
300 		skb_pull(*skb, sizeof (struct rfmon_header));
301 
302 	(*skb)->protocol = htons(ETH_P_802_2);
303 	skb_reset_mac_header(*skb);
304 	(*skb)->pkt_type = PACKET_OTHERHOST;
305 
306 	return 0;
307 }
308 
309 int
islpci_eth_receive(islpci_private * priv)310 islpci_eth_receive(islpci_private *priv)
311 {
312 	struct net_device *ndev = priv->ndev;
313 	isl38xx_control_block *control_block = priv->control_block;
314 	struct sk_buff *skb;
315 	u16 size;
316 	u32 index, offset;
317 	unsigned char *src;
318 	int discard = 0;
319 
320 #if VERBOSE > SHOW_ERROR_MESSAGES
321 	DEBUG(SHOW_FUNCTION_CALLS, "islpci_eth_receive\n");
322 #endif
323 
324 	/* the device has written an Ethernet frame in the data area
325 	 * of the sk_buff without updating the structure, do it now */
326 	index = priv->free_data_rx % ISL38XX_CB_RX_QSIZE;
327 	size = le16_to_cpu(control_block->rx_data_low[index].size);
328 	skb = priv->data_low_rx[index];
329 	offset = ((unsigned long)
330 		  le32_to_cpu(control_block->rx_data_low[index].address) -
331 		  (unsigned long) skb->data) & 3;
332 
333 #if VERBOSE > SHOW_ERROR_MESSAGES
334 	DEBUG(SHOW_TRACING,
335 	      "frq->addr %x skb->data %p skb->len %u offset %u truesize %u\n ",
336 	      control_block->rx_data_low[priv->free_data_rx].address, skb->data,
337 	      skb->len, offset, skb->truesize);
338 #endif
339 
340 	/* delete the streaming DMA mapping before processing the skb */
341 	pci_unmap_single(priv->pdev,
342 			 priv->pci_map_rx_address[index],
343 			 MAX_FRAGMENT_SIZE_RX + 2, PCI_DMA_FROMDEVICE);
344 
345 	/* update the skb structure and align the buffer */
346 	skb_put(skb, size);
347 	if (offset) {
348 		/* shift the buffer allocation offset bytes to get the right frame */
349 		skb_pull(skb, 2);
350 		skb_put(skb, 2);
351 	}
352 #if VERBOSE > SHOW_ERROR_MESSAGES
353 	/* display the buffer contents for debugging */
354 	DEBUG(SHOW_BUFFER_CONTENTS, "\nrx %p ", skb->data);
355 	display_buffer((char *) skb->data, skb->len);
356 #endif
357 
358 	/* check whether WDS is enabled and whether the data frame is a WDS frame */
359 
360 	if (init_wds) {
361 		/* WDS enabled, check for the wds address on the first 6 bytes of the buffer */
362 		src = skb->data + 6;
363 		memmove(skb->data, src, skb->len - 6);
364 		skb_trim(skb, skb->len - 6);
365 	}
366 #if VERBOSE > SHOW_ERROR_MESSAGES
367 	DEBUG(SHOW_TRACING, "Fragment size %i in skb at %p\n", size, skb);
368 	DEBUG(SHOW_TRACING, "Skb data at %p, length %i\n", skb->data, skb->len);
369 
370 	/* display the buffer contents for debugging */
371 	DEBUG(SHOW_BUFFER_CONTENTS, "\nrx %p ", skb->data);
372 	display_buffer((char *) skb->data, skb->len);
373 #endif
374 	/* take care of monitor mode and spy monitoring. */
375 	if (unlikely(priv->iw_mode == IW_MODE_MONITOR)) {
376 		skb->dev = ndev;
377 		discard = islpci_monitor_rx(priv, &skb);
378 	} else {
379 		if (unlikely(skb->data[2 * ETH_ALEN] == 0)) {
380 			/* The packet has a rx_annex. Read it for spy monitoring, Then
381 			 * remove it, while keeping the 2 leading MAC addr.
382 			 */
383 			struct iw_quality wstats;
384 			struct rx_annex_header *annex =
385 			    (struct rx_annex_header *) skb->data;
386 			wstats.level = annex->rfmon.rssi;
387 			/* The noise value can be a bit outdated if nobody's
388 			 * reading wireless stats... */
389 			wstats.noise = priv->local_iwstatistics.qual.noise;
390 			wstats.qual = wstats.level - wstats.noise;
391 			wstats.updated = 0x07;
392 			/* Update spy records */
393 			wireless_spy_update(ndev, annex->addr2, &wstats);
394 
395 			skb_copy_from_linear_data(skb,
396 						  (skb->data +
397 						   sizeof(struct rfmon_header)),
398 						  2 * ETH_ALEN);
399 			skb_pull(skb, sizeof (struct rfmon_header));
400 		}
401 		skb->protocol = eth_type_trans(skb, ndev);
402 	}
403 	skb->ip_summed = CHECKSUM_NONE;
404 	ndev->stats.rx_packets++;
405 	ndev->stats.rx_bytes += size;
406 
407 	/* deliver the skb to the network layer */
408 #ifdef ISLPCI_ETH_DEBUG
409 	printk
410 	    ("islpci_eth_receive:netif_rx %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
411 	     skb->data[0], skb->data[1], skb->data[2], skb->data[3],
412 	     skb->data[4], skb->data[5]);
413 #endif
414 	if (unlikely(discard)) {
415 		dev_kfree_skb_irq(skb);
416 		skb = NULL;
417 	} else
418 		netif_rx(skb);
419 
420 	/* increment the read index for the rx data low queue */
421 	priv->free_data_rx++;
422 
423 	/* add one or more sk_buff structures */
424 	while (index =
425 	       le32_to_cpu(control_block->
426 			   driver_curr_frag[ISL38XX_CB_RX_DATA_LQ]),
427 	       index - priv->free_data_rx < ISL38XX_CB_RX_QSIZE) {
428 		/* allocate an sk_buff for received data frames storage
429 		 * include any required allignment operations */
430 		skb = dev_alloc_skb(MAX_FRAGMENT_SIZE_RX + 2);
431 		if (unlikely(skb == NULL)) {
432 			/* error allocating an sk_buff structure elements */
433 			DEBUG(SHOW_ERROR_MESSAGES, "Error allocating skb\n");
434 			break;
435 		}
436 		skb_reserve(skb, (4 - (long) skb->data) & 0x03);
437 		/* store the new skb structure pointer */
438 		index = index % ISL38XX_CB_RX_QSIZE;
439 		priv->data_low_rx[index] = skb;
440 
441 #if VERBOSE > SHOW_ERROR_MESSAGES
442 		DEBUG(SHOW_TRACING,
443 		      "new alloc skb %p skb->data %p skb->len %u index %u truesize %u\n ",
444 		      skb, skb->data, skb->len, index, skb->truesize);
445 #endif
446 
447 		/* set the streaming DMA mapping for proper PCI bus operation */
448 		priv->pci_map_rx_address[index] =
449 		    pci_map_single(priv->pdev, (void *) skb->data,
450 				   MAX_FRAGMENT_SIZE_RX + 2,
451 				   PCI_DMA_FROMDEVICE);
452 		if (unlikely(!priv->pci_map_rx_address[index])) {
453 			/* error mapping the buffer to device accessible memory address */
454 			DEBUG(SHOW_ERROR_MESSAGES,
455 			      "Error mapping DMA address\n");
456 
457 			/* free the skbuf structure before aborting */
458 			dev_kfree_skb_irq((struct sk_buff *) skb);
459 			skb = NULL;
460 			break;
461 		}
462 		/* update the fragment address */
463 		control_block->rx_data_low[index].address =
464 			cpu_to_le32((u32)priv->pci_map_rx_address[index]);
465 		wmb();
466 
467 		/* increment the driver read pointer */
468 		le32_add_cpu(&control_block->
469 			     driver_curr_frag[ISL38XX_CB_RX_DATA_LQ], 1);
470 	}
471 
472 	/* trigger the device */
473 	islpci_trigger(priv);
474 
475 	return 0;
476 }
477 
478 void
islpci_do_reset_and_wake(struct work_struct * work)479 islpci_do_reset_and_wake(struct work_struct *work)
480 {
481 	islpci_private *priv = container_of(work, islpci_private, reset_task);
482 
483 	islpci_reset(priv, 1);
484 	priv->reset_task_pending = 0;
485 	smp_wmb();
486 	netif_wake_queue(priv->ndev);
487 }
488 
489 void
islpci_eth_tx_timeout(struct net_device * ndev)490 islpci_eth_tx_timeout(struct net_device *ndev)
491 {
492 	islpci_private *priv = netdev_priv(ndev);
493 
494 	/* increment the transmit error counter */
495 	ndev->stats.tx_errors++;
496 
497 	if (!priv->reset_task_pending) {
498 		printk(KERN_WARNING
499 			"%s: tx_timeout, scheduling reset", ndev->name);
500 		netif_stop_queue(ndev);
501 		priv->reset_task_pending = 1;
502 		schedule_work(&priv->reset_task);
503 	} else {
504 		printk(KERN_WARNING
505 			"%s: tx_timeout, waiting for reset", ndev->name);
506 	}
507 }
508