xref: /linux/drivers/net/wireless/ath/wil6210/txrx.c (revision 110e6f26af80dfd90b6e5c645b1aed7228aa580d)
1 /*
2  * Copyright (c) 2012-2016 Qualcomm Atheros, Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <linux/etherdevice.h>
18 #include <net/ieee80211_radiotap.h>
19 #include <linux/if_arp.h>
20 #include <linux/moduleparam.h>
21 #include <linux/ip.h>
22 #include <linux/ipv6.h>
23 #include <net/ipv6.h>
24 #include <linux/prefetch.h>
25 
26 #include "wil6210.h"
27 #include "wmi.h"
28 #include "txrx.h"
29 #include "trace.h"
30 
31 static bool rtap_include_phy_info;
32 module_param(rtap_include_phy_info, bool, S_IRUGO);
33 MODULE_PARM_DESC(rtap_include_phy_info,
34 		 " Include PHY info in the radiotap header, default - no");
35 
36 bool rx_align_2;
37 module_param(rx_align_2, bool, S_IRUGO);
38 MODULE_PARM_DESC(rx_align_2, " align Rx buffers on 4*n+2, default - no");
39 
40 static inline uint wil_rx_snaplen(void)
41 {
42 	return rx_align_2 ? 6 : 0;
43 }
44 
45 static inline int wil_vring_is_empty(struct vring *vring)
46 {
47 	return vring->swhead == vring->swtail;
48 }
49 
50 static inline u32 wil_vring_next_tail(struct vring *vring)
51 {
52 	return (vring->swtail + 1) % vring->size;
53 }
54 
55 static inline void wil_vring_advance_head(struct vring *vring, int n)
56 {
57 	vring->swhead = (vring->swhead + n) % vring->size;
58 }
59 
60 static inline int wil_vring_is_full(struct vring *vring)
61 {
62 	return wil_vring_next_tail(vring) == vring->swhead;
63 }
64 
65 /* Used space in Tx Vring */
66 static inline int wil_vring_used_tx(struct vring *vring)
67 {
68 	u32 swhead = vring->swhead;
69 	u32 swtail = vring->swtail;
70 	return (vring->size + swhead - swtail) % vring->size;
71 }
72 
73 /* Available space in Tx Vring */
74 static inline int wil_vring_avail_tx(struct vring *vring)
75 {
76 	return vring->size - wil_vring_used_tx(vring) - 1;
77 }
78 
79 /* wil_vring_wmark_low - low watermark for available descriptor space */
80 static inline int wil_vring_wmark_low(struct vring *vring)
81 {
82 	return vring->size/8;
83 }
84 
85 /* wil_vring_wmark_high - high watermark for available descriptor space */
86 static inline int wil_vring_wmark_high(struct vring *vring)
87 {
88 	return vring->size/4;
89 }
90 
91 /* wil_val_in_range - check if value in [min,max) */
92 static inline bool wil_val_in_range(int val, int min, int max)
93 {
94 	return val >= min && val < max;
95 }
96 
97 static int wil_vring_alloc(struct wil6210_priv *wil, struct vring *vring)
98 {
99 	struct device *dev = wil_to_dev(wil);
100 	size_t sz = vring->size * sizeof(vring->va[0]);
101 	uint i;
102 
103 	wil_dbg_misc(wil, "%s()\n", __func__);
104 
105 	BUILD_BUG_ON(sizeof(vring->va[0]) != 32);
106 
107 	vring->swhead = 0;
108 	vring->swtail = 0;
109 	vring->ctx = kcalloc(vring->size, sizeof(vring->ctx[0]), GFP_KERNEL);
110 	if (!vring->ctx) {
111 		vring->va = NULL;
112 		return -ENOMEM;
113 	}
114 	/* vring->va should be aligned on its size rounded up to power of 2
115 	 * This is granted by the dma_alloc_coherent
116 	 */
117 	vring->va = dma_alloc_coherent(dev, sz, &vring->pa, GFP_KERNEL);
118 	if (!vring->va) {
119 		kfree(vring->ctx);
120 		vring->ctx = NULL;
121 		return -ENOMEM;
122 	}
123 	/* initially, all descriptors are SW owned
124 	 * For Tx and Rx, ownership bit is at the same location, thus
125 	 * we can use any
126 	 */
127 	for (i = 0; i < vring->size; i++) {
128 		volatile struct vring_tx_desc *_d = &vring->va[i].tx;
129 
130 		_d->dma.status = TX_DMA_STATUS_DU;
131 	}
132 
133 	wil_dbg_misc(wil, "vring[%d] 0x%p:%pad 0x%p\n", vring->size,
134 		     vring->va, &vring->pa, vring->ctx);
135 
136 	return 0;
137 }
138 
139 static void wil_txdesc_unmap(struct device *dev, struct vring_tx_desc *d,
140 			     struct wil_ctx *ctx)
141 {
142 	dma_addr_t pa = wil_desc_addr(&d->dma.addr);
143 	u16 dmalen = le16_to_cpu(d->dma.length);
144 
145 	switch (ctx->mapped_as) {
146 	case wil_mapped_as_single:
147 		dma_unmap_single(dev, pa, dmalen, DMA_TO_DEVICE);
148 		break;
149 	case wil_mapped_as_page:
150 		dma_unmap_page(dev, pa, dmalen, DMA_TO_DEVICE);
151 		break;
152 	default:
153 		break;
154 	}
155 }
156 
157 static void wil_vring_free(struct wil6210_priv *wil, struct vring *vring,
158 			   int tx)
159 {
160 	struct device *dev = wil_to_dev(wil);
161 	size_t sz = vring->size * sizeof(vring->va[0]);
162 
163 	lockdep_assert_held(&wil->mutex);
164 	if (tx) {
165 		int vring_index = vring - wil->vring_tx;
166 
167 		wil_dbg_misc(wil, "free Tx vring %d [%d] 0x%p:%pad 0x%p\n",
168 			     vring_index, vring->size, vring->va,
169 			     &vring->pa, vring->ctx);
170 	} else {
171 		wil_dbg_misc(wil, "free Rx vring [%d] 0x%p:%pad 0x%p\n",
172 			     vring->size, vring->va,
173 			     &vring->pa, vring->ctx);
174 	}
175 
176 	while (!wil_vring_is_empty(vring)) {
177 		dma_addr_t pa;
178 		u16 dmalen;
179 		struct wil_ctx *ctx;
180 
181 		if (tx) {
182 			struct vring_tx_desc dd, *d = &dd;
183 			volatile struct vring_tx_desc *_d =
184 					&vring->va[vring->swtail].tx;
185 
186 			ctx = &vring->ctx[vring->swtail];
187 			*d = *_d;
188 			wil_txdesc_unmap(dev, d, ctx);
189 			if (ctx->skb)
190 				dev_kfree_skb_any(ctx->skb);
191 			vring->swtail = wil_vring_next_tail(vring);
192 		} else { /* rx */
193 			struct vring_rx_desc dd, *d = &dd;
194 			volatile struct vring_rx_desc *_d =
195 					&vring->va[vring->swhead].rx;
196 
197 			ctx = &vring->ctx[vring->swhead];
198 			*d = *_d;
199 			pa = wil_desc_addr(&d->dma.addr);
200 			dmalen = le16_to_cpu(d->dma.length);
201 			dma_unmap_single(dev, pa, dmalen, DMA_FROM_DEVICE);
202 			kfree_skb(ctx->skb);
203 			wil_vring_advance_head(vring, 1);
204 		}
205 	}
206 	dma_free_coherent(dev, sz, (void *)vring->va, vring->pa);
207 	kfree(vring->ctx);
208 	vring->pa = 0;
209 	vring->va = NULL;
210 	vring->ctx = NULL;
211 }
212 
213 /**
214  * Allocate one skb for Rx VRING
215  *
216  * Safe to call from IRQ
217  */
218 static int wil_vring_alloc_skb(struct wil6210_priv *wil, struct vring *vring,
219 			       u32 i, int headroom)
220 {
221 	struct device *dev = wil_to_dev(wil);
222 	unsigned int sz = mtu_max + ETH_HLEN + wil_rx_snaplen();
223 	struct vring_rx_desc dd, *d = &dd;
224 	volatile struct vring_rx_desc *_d = &vring->va[i].rx;
225 	dma_addr_t pa;
226 	struct sk_buff *skb = dev_alloc_skb(sz + headroom);
227 
228 	if (unlikely(!skb))
229 		return -ENOMEM;
230 
231 	skb_reserve(skb, headroom);
232 	skb_put(skb, sz);
233 
234 	pa = dma_map_single(dev, skb->data, skb->len, DMA_FROM_DEVICE);
235 	if (unlikely(dma_mapping_error(dev, pa))) {
236 		kfree_skb(skb);
237 		return -ENOMEM;
238 	}
239 
240 	d->dma.d0 = RX_DMA_D0_CMD_DMA_RT | RX_DMA_D0_CMD_DMA_IT;
241 	wil_desc_addr_set(&d->dma.addr, pa);
242 	/* ip_length don't care */
243 	/* b11 don't care */
244 	/* error don't care */
245 	d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
246 	d->dma.length = cpu_to_le16(sz);
247 	*_d = *d;
248 	vring->ctx[i].skb = skb;
249 
250 	return 0;
251 }
252 
253 /**
254  * Adds radiotap header
255  *
256  * Any error indicated as "Bad FCS"
257  *
258  * Vendor data for 04:ce:14-1 (Wilocity-1) consists of:
259  *  - Rx descriptor: 32 bytes
260  *  - Phy info
261  */
262 static void wil_rx_add_radiotap_header(struct wil6210_priv *wil,
263 				       struct sk_buff *skb)
264 {
265 	struct wireless_dev *wdev = wil->wdev;
266 	struct wil6210_rtap {
267 		struct ieee80211_radiotap_header rthdr;
268 		/* fields should be in the order of bits in rthdr.it_present */
269 		/* flags */
270 		u8 flags;
271 		/* channel */
272 		__le16 chnl_freq __aligned(2);
273 		__le16 chnl_flags;
274 		/* MCS */
275 		u8 mcs_present;
276 		u8 mcs_flags;
277 		u8 mcs_index;
278 	} __packed;
279 	struct wil6210_rtap_vendor {
280 		struct wil6210_rtap rtap;
281 		/* vendor */
282 		u8 vendor_oui[3] __aligned(2);
283 		u8 vendor_ns;
284 		__le16 vendor_skip;
285 		u8 vendor_data[0];
286 	} __packed;
287 	struct vring_rx_desc *d = wil_skb_rxdesc(skb);
288 	struct wil6210_rtap_vendor *rtap_vendor;
289 	int rtap_len = sizeof(struct wil6210_rtap);
290 	int phy_length = 0; /* phy info header size, bytes */
291 	static char phy_data[128];
292 	struct ieee80211_channel *ch = wdev->preset_chandef.chan;
293 
294 	if (rtap_include_phy_info) {
295 		rtap_len = sizeof(*rtap_vendor) + sizeof(*d);
296 		/* calculate additional length */
297 		if (d->dma.status & RX_DMA_STATUS_PHY_INFO) {
298 			/**
299 			 * PHY info starts from 8-byte boundary
300 			 * there are 8-byte lines, last line may be partially
301 			 * written (HW bug), thus FW configures for last line
302 			 * to be excessive. Driver skips this last line.
303 			 */
304 			int len = min_t(int, 8 + sizeof(phy_data),
305 					wil_rxdesc_phy_length(d));
306 
307 			if (len > 8) {
308 				void *p = skb_tail_pointer(skb);
309 				void *pa = PTR_ALIGN(p, 8);
310 
311 				if (skb_tailroom(skb) >= len + (pa - p)) {
312 					phy_length = len - 8;
313 					memcpy(phy_data, pa, phy_length);
314 				}
315 			}
316 		}
317 		rtap_len += phy_length;
318 	}
319 
320 	if (skb_headroom(skb) < rtap_len &&
321 	    pskb_expand_head(skb, rtap_len, 0, GFP_ATOMIC)) {
322 		wil_err(wil, "Unable to expand headrom to %d\n", rtap_len);
323 		return;
324 	}
325 
326 	rtap_vendor = (void *)skb_push(skb, rtap_len);
327 	memset(rtap_vendor, 0, rtap_len);
328 
329 	rtap_vendor->rtap.rthdr.it_version = PKTHDR_RADIOTAP_VERSION;
330 	rtap_vendor->rtap.rthdr.it_len = cpu_to_le16(rtap_len);
331 	rtap_vendor->rtap.rthdr.it_present = cpu_to_le32(
332 			(1 << IEEE80211_RADIOTAP_FLAGS) |
333 			(1 << IEEE80211_RADIOTAP_CHANNEL) |
334 			(1 << IEEE80211_RADIOTAP_MCS));
335 	if (d->dma.status & RX_DMA_STATUS_ERROR)
336 		rtap_vendor->rtap.flags |= IEEE80211_RADIOTAP_F_BADFCS;
337 
338 	rtap_vendor->rtap.chnl_freq = cpu_to_le16(ch ? ch->center_freq : 58320);
339 	rtap_vendor->rtap.chnl_flags = cpu_to_le16(0);
340 
341 	rtap_vendor->rtap.mcs_present = IEEE80211_RADIOTAP_MCS_HAVE_MCS;
342 	rtap_vendor->rtap.mcs_flags = 0;
343 	rtap_vendor->rtap.mcs_index = wil_rxdesc_mcs(d);
344 
345 	if (rtap_include_phy_info) {
346 		rtap_vendor->rtap.rthdr.it_present |= cpu_to_le32(1 <<
347 				IEEE80211_RADIOTAP_VENDOR_NAMESPACE);
348 		/* OUI for Wilocity 04:ce:14 */
349 		rtap_vendor->vendor_oui[0] = 0x04;
350 		rtap_vendor->vendor_oui[1] = 0xce;
351 		rtap_vendor->vendor_oui[2] = 0x14;
352 		rtap_vendor->vendor_ns = 1;
353 		/* Rx descriptor + PHY data  */
354 		rtap_vendor->vendor_skip = cpu_to_le16(sizeof(*d) +
355 						       phy_length);
356 		memcpy(rtap_vendor->vendor_data, (void *)d, sizeof(*d));
357 		memcpy(rtap_vendor->vendor_data + sizeof(*d), phy_data,
358 		       phy_length);
359 	}
360 }
361 
362 /* similar to ieee80211_ version, but FC contain only 1-st byte */
363 static inline int wil_is_back_req(u8 fc)
364 {
365 	return (fc & (IEEE80211_FCTL_FTYPE | IEEE80211_FCTL_STYPE)) ==
366 	       (IEEE80211_FTYPE_CTL | IEEE80211_STYPE_BACK_REQ);
367 }
368 
369 /**
370  * reap 1 frame from @swhead
371  *
372  * Rx descriptor copied to skb->cb
373  *
374  * Safe to call from IRQ
375  */
376 static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
377 					 struct vring *vring)
378 {
379 	struct device *dev = wil_to_dev(wil);
380 	struct net_device *ndev = wil_to_ndev(wil);
381 	volatile struct vring_rx_desc *_d;
382 	struct vring_rx_desc *d;
383 	struct sk_buff *skb;
384 	dma_addr_t pa;
385 	unsigned int snaplen = wil_rx_snaplen();
386 	unsigned int sz = mtu_max + ETH_HLEN + snaplen;
387 	u16 dmalen;
388 	u8 ftype;
389 	int cid;
390 	int i;
391 	struct wil_net_stats *stats;
392 
393 	BUILD_BUG_ON(sizeof(struct vring_rx_desc) > sizeof(skb->cb));
394 
395 again:
396 	if (unlikely(wil_vring_is_empty(vring)))
397 		return NULL;
398 
399 	i = (int)vring->swhead;
400 	_d = &vring->va[i].rx;
401 	if (unlikely(!(_d->dma.status & RX_DMA_STATUS_DU))) {
402 		/* it is not error, we just reached end of Rx done area */
403 		return NULL;
404 	}
405 
406 	skb = vring->ctx[i].skb;
407 	vring->ctx[i].skb = NULL;
408 	wil_vring_advance_head(vring, 1);
409 	if (!skb) {
410 		wil_err(wil, "No Rx skb at [%d]\n", i);
411 		goto again;
412 	}
413 	d = wil_skb_rxdesc(skb);
414 	*d = *_d;
415 	pa = wil_desc_addr(&d->dma.addr);
416 
417 	dma_unmap_single(dev, pa, sz, DMA_FROM_DEVICE);
418 	dmalen = le16_to_cpu(d->dma.length);
419 
420 	trace_wil6210_rx(i, d);
421 	wil_dbg_txrx(wil, "Rx[%3d] : %d bytes\n", i, dmalen);
422 	wil_hex_dump_txrx("RxD ", DUMP_PREFIX_NONE, 32, 4,
423 			  (const void *)d, sizeof(*d), false);
424 
425 	cid = wil_rxdesc_cid(d);
426 	stats = &wil->sta[cid].stats;
427 
428 	if (unlikely(dmalen > sz)) {
429 		wil_err(wil, "Rx size too large: %d bytes!\n", dmalen);
430 		stats->rx_large_frame++;
431 		kfree_skb(skb);
432 		goto again;
433 	}
434 	skb_trim(skb, dmalen);
435 
436 	prefetch(skb->data);
437 
438 	wil_hex_dump_txrx("Rx ", DUMP_PREFIX_OFFSET, 16, 1,
439 			  skb->data, skb_headlen(skb), false);
440 
441 	stats->last_mcs_rx = wil_rxdesc_mcs(d);
442 	if (stats->last_mcs_rx < ARRAY_SIZE(stats->rx_per_mcs))
443 		stats->rx_per_mcs[stats->last_mcs_rx]++;
444 
445 	/* use radiotap header only if required */
446 	if (ndev->type == ARPHRD_IEEE80211_RADIOTAP)
447 		wil_rx_add_radiotap_header(wil, skb);
448 
449 	/* no extra checks if in sniffer mode */
450 	if (ndev->type != ARPHRD_ETHER)
451 		return skb;
452 	/* Non-data frames may be delivered through Rx DMA channel (ex: BAR)
453 	 * Driver should recognize it by frame type, that is found
454 	 * in Rx descriptor. If type is not data, it is 802.11 frame as is
455 	 */
456 	ftype = wil_rxdesc_ftype(d) << 2;
457 	if (unlikely(ftype != IEEE80211_FTYPE_DATA)) {
458 		u8 fc1 = wil_rxdesc_fc1(d);
459 		int mid = wil_rxdesc_mid(d);
460 		int tid = wil_rxdesc_tid(d);
461 		u16 seq = wil_rxdesc_seq(d);
462 
463 		wil_dbg_txrx(wil,
464 			     "Non-data frame FC[7:0] 0x%02x MID %d CID %d TID %d Seq 0x%03x\n",
465 			     fc1, mid, cid, tid, seq);
466 		stats->rx_non_data_frame++;
467 		if (wil_is_back_req(fc1)) {
468 			wil_dbg_txrx(wil,
469 				     "BAR: MID %d CID %d TID %d Seq 0x%03x\n",
470 				     mid, cid, tid, seq);
471 			wil_rx_bar(wil, cid, tid, seq);
472 		} else {
473 			/* print again all info. One can enable only this
474 			 * without overhead for printing every Rx frame
475 			 */
476 			wil_dbg_txrx(wil,
477 				     "Unhandled non-data frame FC[7:0] 0x%02x MID %d CID %d TID %d Seq 0x%03x\n",
478 				     fc1, mid, cid, tid, seq);
479 			wil_hex_dump_txrx("RxD ", DUMP_PREFIX_NONE, 32, 4,
480 					  (const void *)d, sizeof(*d), false);
481 			wil_hex_dump_txrx("Rx ", DUMP_PREFIX_OFFSET, 16, 1,
482 					  skb->data, skb_headlen(skb), false);
483 		}
484 		kfree_skb(skb);
485 		goto again;
486 	}
487 
488 	if (unlikely(skb->len < ETH_HLEN + snaplen)) {
489 		wil_err(wil, "Short frame, len = %d\n", skb->len);
490 		stats->rx_short_frame++;
491 		kfree_skb(skb);
492 		goto again;
493 	}
494 
495 	/* L4 IDENT is on when HW calculated checksum, check status
496 	 * and in case of error drop the packet
497 	 * higher stack layers will handle retransmission (if required)
498 	 */
499 	if (likely(d->dma.status & RX_DMA_STATUS_L4I)) {
500 		/* L4 protocol identified, csum calculated */
501 		if (likely((d->dma.error & RX_DMA_ERROR_L4_ERR) == 0))
502 			skb->ip_summed = CHECKSUM_UNNECESSARY;
503 		/* If HW reports bad checksum, let IP stack re-check it
504 		 * For example, HW don't understand Microsoft IP stack that
505 		 * mis-calculates TCP checksum - if it should be 0x0,
506 		 * it writes 0xffff in violation of RFC 1624
507 		 */
508 	}
509 
510 	if (snaplen) {
511 		/* Packet layout
512 		 * +-------+-------+---------+------------+------+
513 		 * | SA(6) | DA(6) | SNAP(6) | ETHTYPE(2) | DATA |
514 		 * +-------+-------+---------+------------+------+
515 		 * Need to remove SNAP, shifting SA and DA forward
516 		 */
517 		memmove(skb->data + snaplen, skb->data, 2 * ETH_ALEN);
518 		skb_pull(skb, snaplen);
519 	}
520 
521 	return skb;
522 }
523 
524 /**
525  * allocate and fill up to @count buffers in rx ring
526  * buffers posted at @swtail
527  */
528 static int wil_rx_refill(struct wil6210_priv *wil, int count)
529 {
530 	struct net_device *ndev = wil_to_ndev(wil);
531 	struct vring *v = &wil->vring_rx;
532 	u32 next_tail;
533 	int rc = 0;
534 	int headroom = ndev->type == ARPHRD_IEEE80211_RADIOTAP ?
535 			WIL6210_RTAP_SIZE : 0;
536 
537 	for (; next_tail = wil_vring_next_tail(v),
538 			(next_tail != v->swhead) && (count-- > 0);
539 			v->swtail = next_tail) {
540 		rc = wil_vring_alloc_skb(wil, v, v->swtail, headroom);
541 		if (unlikely(rc)) {
542 			wil_err(wil, "Error %d in wil_rx_refill[%d]\n",
543 				rc, v->swtail);
544 			break;
545 		}
546 	}
547 	wil_w(wil, v->hwtail, v->swtail);
548 
549 	return rc;
550 }
551 
552 /*
553  * Pass Rx packet to the netif. Update statistics.
554  * Called in softirq context (NAPI poll).
555  */
556 void wil_netif_rx_any(struct sk_buff *skb, struct net_device *ndev)
557 {
558 	gro_result_t rc = GRO_NORMAL;
559 	struct wil6210_priv *wil = ndev_to_wil(ndev);
560 	struct wireless_dev *wdev = wil_to_wdev(wil);
561 	unsigned int len = skb->len;
562 	struct vring_rx_desc *d = wil_skb_rxdesc(skb);
563 	int cid = wil_rxdesc_cid(d); /* always 0..7, no need to check */
564 	struct ethhdr *eth = (void *)skb->data;
565 	/* here looking for DA, not A1, thus Rxdesc's 'mcast' indication
566 	 * is not suitable, need to look at data
567 	 */
568 	int mcast = is_multicast_ether_addr(eth->h_dest);
569 	struct wil_net_stats *stats = &wil->sta[cid].stats;
570 	struct sk_buff *xmit_skb = NULL;
571 	static const char * const gro_res_str[] = {
572 		[GRO_MERGED]		= "GRO_MERGED",
573 		[GRO_MERGED_FREE]	= "GRO_MERGED_FREE",
574 		[GRO_HELD]		= "GRO_HELD",
575 		[GRO_NORMAL]		= "GRO_NORMAL",
576 		[GRO_DROP]		= "GRO_DROP",
577 	};
578 
579 	if (ndev->features & NETIF_F_RXHASH)
580 		/* fake L4 to ensure it won't be re-calculated later
581 		 * set hash to any non-zero value to activate rps
582 		 * mechanism, core will be chosen according
583 		 * to user-level rps configuration.
584 		 */
585 		skb_set_hash(skb, 1, PKT_HASH_TYPE_L4);
586 
587 	skb_orphan(skb);
588 
589 	if (wdev->iftype == NL80211_IFTYPE_AP && !wil->ap_isolate) {
590 		if (mcast) {
591 			/* send multicast frames both to higher layers in
592 			 * local net stack and back to the wireless medium
593 			 */
594 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
595 		} else {
596 			int xmit_cid = wil_find_cid(wil, eth->h_dest);
597 
598 			if (xmit_cid >= 0) {
599 				/* The destination station is associated to
600 				 * this AP (in this VLAN), so send the frame
601 				 * directly to it and do not pass it to local
602 				 * net stack.
603 				 */
604 				xmit_skb = skb;
605 				skb = NULL;
606 			}
607 		}
608 	}
609 	if (xmit_skb) {
610 		/* Send to wireless media and increase priority by 256 to
611 		 * keep the received priority instead of reclassifying
612 		 * the frame (see cfg80211_classify8021d).
613 		 */
614 		xmit_skb->dev = ndev;
615 		xmit_skb->priority += 256;
616 		xmit_skb->protocol = htons(ETH_P_802_3);
617 		skb_reset_network_header(xmit_skb);
618 		skb_reset_mac_header(xmit_skb);
619 		wil_dbg_txrx(wil, "Rx -> Tx %d bytes\n", len);
620 		dev_queue_xmit(xmit_skb);
621 	}
622 
623 	if (skb) { /* deliver to local stack */
624 
625 		skb->protocol = eth_type_trans(skb, ndev);
626 		rc = napi_gro_receive(&wil->napi_rx, skb);
627 		wil_dbg_txrx(wil, "Rx complete %d bytes => %s\n",
628 			     len, gro_res_str[rc]);
629 	}
630 	/* statistics. rc set to GRO_NORMAL for AP bridging */
631 	if (unlikely(rc == GRO_DROP)) {
632 		ndev->stats.rx_dropped++;
633 		stats->rx_dropped++;
634 		wil_dbg_txrx(wil, "Rx drop %d bytes\n", len);
635 	} else {
636 		ndev->stats.rx_packets++;
637 		stats->rx_packets++;
638 		ndev->stats.rx_bytes += len;
639 		stats->rx_bytes += len;
640 		if (mcast)
641 			ndev->stats.multicast++;
642 	}
643 }
644 
645 /**
646  * Proceed all completed skb's from Rx VRING
647  *
648  * Safe to call from NAPI poll, i.e. softirq with interrupts enabled
649  */
650 void wil_rx_handle(struct wil6210_priv *wil, int *quota)
651 {
652 	struct net_device *ndev = wil_to_ndev(wil);
653 	struct vring *v = &wil->vring_rx;
654 	struct sk_buff *skb;
655 
656 	if (unlikely(!v->va)) {
657 		wil_err(wil, "Rx IRQ while Rx not yet initialized\n");
658 		return;
659 	}
660 	wil_dbg_txrx(wil, "%s()\n", __func__);
661 	while ((*quota > 0) && (NULL != (skb = wil_vring_reap_rx(wil, v)))) {
662 		(*quota)--;
663 
664 		if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
665 			skb->dev = ndev;
666 			skb_reset_mac_header(skb);
667 			skb->ip_summed = CHECKSUM_UNNECESSARY;
668 			skb->pkt_type = PACKET_OTHERHOST;
669 			skb->protocol = htons(ETH_P_802_2);
670 			wil_netif_rx_any(skb, ndev);
671 		} else {
672 			wil_rx_reorder(wil, skb);
673 		}
674 	}
675 	wil_rx_refill(wil, v->size);
676 }
677 
678 int wil_rx_init(struct wil6210_priv *wil, u16 size)
679 {
680 	struct vring *vring = &wil->vring_rx;
681 	int rc;
682 
683 	wil_dbg_misc(wil, "%s()\n", __func__);
684 
685 	if (vring->va) {
686 		wil_err(wil, "Rx ring already allocated\n");
687 		return -EINVAL;
688 	}
689 
690 	vring->size = size;
691 	rc = wil_vring_alloc(wil, vring);
692 	if (rc)
693 		return rc;
694 
695 	rc = wmi_rx_chain_add(wil, vring);
696 	if (rc)
697 		goto err_free;
698 
699 	rc = wil_rx_refill(wil, vring->size);
700 	if (rc)
701 		goto err_free;
702 
703 	return 0;
704  err_free:
705 	wil_vring_free(wil, vring, 0);
706 
707 	return rc;
708 }
709 
710 void wil_rx_fini(struct wil6210_priv *wil)
711 {
712 	struct vring *vring = &wil->vring_rx;
713 
714 	wil_dbg_misc(wil, "%s()\n", __func__);
715 
716 	if (vring->va)
717 		wil_vring_free(wil, vring, 0);
718 }
719 
720 static inline void wil_tx_data_init(struct vring_tx_data *txdata)
721 {
722 	spin_lock_bh(&txdata->lock);
723 	txdata->dot1x_open = 0;
724 	txdata->enabled = 0;
725 	txdata->idle = 0;
726 	txdata->last_idle = 0;
727 	txdata->begin = 0;
728 	txdata->agg_wsize = 0;
729 	txdata->agg_timeout = 0;
730 	txdata->agg_amsdu = 0;
731 	txdata->addba_in_progress = false;
732 	spin_unlock_bh(&txdata->lock);
733 }
734 
735 int wil_vring_init_tx(struct wil6210_priv *wil, int id, int size,
736 		      int cid, int tid)
737 {
738 	int rc;
739 	struct wmi_vring_cfg_cmd cmd = {
740 		.action = cpu_to_le32(WMI_VRING_CMD_ADD),
741 		.vring_cfg = {
742 			.tx_sw_ring = {
743 				.max_mpdu_size =
744 					cpu_to_le16(wil_mtu2macbuf(mtu_max)),
745 				.ring_size = cpu_to_le16(size),
746 			},
747 			.ringid = id,
748 			.cidxtid = mk_cidxtid(cid, tid),
749 			.encap_trans_type = WMI_VRING_ENC_TYPE_802_3,
750 			.mac_ctrl = 0,
751 			.to_resolution = 0,
752 			.agg_max_wsize = 0,
753 			.schd_params = {
754 				.priority = cpu_to_le16(0),
755 				.timeslot_us = cpu_to_le16(0xfff),
756 			},
757 		},
758 	};
759 	struct {
760 		struct wil6210_mbox_hdr_wmi wmi;
761 		struct wmi_vring_cfg_done_event cmd;
762 	} __packed reply;
763 	struct vring *vring = &wil->vring_tx[id];
764 	struct vring_tx_data *txdata = &wil->vring_tx_data[id];
765 
766 	wil_dbg_misc(wil, "%s() max_mpdu_size %d\n", __func__,
767 		     cmd.vring_cfg.tx_sw_ring.max_mpdu_size);
768 	lockdep_assert_held(&wil->mutex);
769 
770 	if (vring->va) {
771 		wil_err(wil, "Tx ring [%d] already allocated\n", id);
772 		rc = -EINVAL;
773 		goto out;
774 	}
775 
776 	wil_tx_data_init(txdata);
777 	vring->size = size;
778 	rc = wil_vring_alloc(wil, vring);
779 	if (rc)
780 		goto out;
781 
782 	wil->vring2cid_tid[id][0] = cid;
783 	wil->vring2cid_tid[id][1] = tid;
784 
785 	cmd.vring_cfg.tx_sw_ring.ring_mem_base = cpu_to_le64(vring->pa);
786 
787 	if (!wil->privacy)
788 		txdata->dot1x_open = true;
789 	rc = wmi_call(wil, WMI_VRING_CFG_CMDID, &cmd, sizeof(cmd),
790 		      WMI_VRING_CFG_DONE_EVENTID, &reply, sizeof(reply), 100);
791 	if (rc)
792 		goto out_free;
793 
794 	if (reply.cmd.status != WMI_FW_STATUS_SUCCESS) {
795 		wil_err(wil, "Tx config failed, status 0x%02x\n",
796 			reply.cmd.status);
797 		rc = -EINVAL;
798 		goto out_free;
799 	}
800 	vring->hwtail = le32_to_cpu(reply.cmd.tx_vring_tail_ptr);
801 
802 	txdata->enabled = 1;
803 	if (txdata->dot1x_open && (agg_wsize >= 0))
804 		wil_addba_tx_request(wil, id, agg_wsize);
805 
806 	return 0;
807  out_free:
808 	spin_lock_bh(&txdata->lock);
809 	txdata->dot1x_open = false;
810 	txdata->enabled = 0;
811 	spin_unlock_bh(&txdata->lock);
812 	wil_vring_free(wil, vring, 1);
813 	wil->vring2cid_tid[id][0] = WIL6210_MAX_CID;
814 	wil->vring2cid_tid[id][1] = 0;
815 
816  out:
817 
818 	return rc;
819 }
820 
821 int wil_vring_init_bcast(struct wil6210_priv *wil, int id, int size)
822 {
823 	int rc;
824 	struct wmi_bcast_vring_cfg_cmd cmd = {
825 		.action = cpu_to_le32(WMI_VRING_CMD_ADD),
826 		.vring_cfg = {
827 			.tx_sw_ring = {
828 				.max_mpdu_size =
829 					cpu_to_le16(wil_mtu2macbuf(mtu_max)),
830 				.ring_size = cpu_to_le16(size),
831 			},
832 			.ringid = id,
833 			.encap_trans_type = WMI_VRING_ENC_TYPE_802_3,
834 		},
835 	};
836 	struct {
837 		struct wil6210_mbox_hdr_wmi wmi;
838 		struct wmi_vring_cfg_done_event cmd;
839 	} __packed reply;
840 	struct vring *vring = &wil->vring_tx[id];
841 	struct vring_tx_data *txdata = &wil->vring_tx_data[id];
842 
843 	wil_dbg_misc(wil, "%s() max_mpdu_size %d\n", __func__,
844 		     cmd.vring_cfg.tx_sw_ring.max_mpdu_size);
845 	lockdep_assert_held(&wil->mutex);
846 
847 	if (vring->va) {
848 		wil_err(wil, "Tx ring [%d] already allocated\n", id);
849 		rc = -EINVAL;
850 		goto out;
851 	}
852 
853 	wil_tx_data_init(txdata);
854 	vring->size = size;
855 	rc = wil_vring_alloc(wil, vring);
856 	if (rc)
857 		goto out;
858 
859 	wil->vring2cid_tid[id][0] = WIL6210_MAX_CID; /* CID */
860 	wil->vring2cid_tid[id][1] = 0; /* TID */
861 
862 	cmd.vring_cfg.tx_sw_ring.ring_mem_base = cpu_to_le64(vring->pa);
863 
864 	if (!wil->privacy)
865 		txdata->dot1x_open = true;
866 	rc = wmi_call(wil, WMI_BCAST_VRING_CFG_CMDID, &cmd, sizeof(cmd),
867 		      WMI_VRING_CFG_DONE_EVENTID, &reply, sizeof(reply), 100);
868 	if (rc)
869 		goto out_free;
870 
871 	if (reply.cmd.status != WMI_FW_STATUS_SUCCESS) {
872 		wil_err(wil, "Tx config failed, status 0x%02x\n",
873 			reply.cmd.status);
874 		rc = -EINVAL;
875 		goto out_free;
876 	}
877 	vring->hwtail = le32_to_cpu(reply.cmd.tx_vring_tail_ptr);
878 
879 	txdata->enabled = 1;
880 
881 	return 0;
882  out_free:
883 	spin_lock_bh(&txdata->lock);
884 	txdata->enabled = 0;
885 	txdata->dot1x_open = false;
886 	spin_unlock_bh(&txdata->lock);
887 	wil_vring_free(wil, vring, 1);
888  out:
889 
890 	return rc;
891 }
892 
893 void wil_vring_fini_tx(struct wil6210_priv *wil, int id)
894 {
895 	struct vring *vring = &wil->vring_tx[id];
896 	struct vring_tx_data *txdata = &wil->vring_tx_data[id];
897 
898 	lockdep_assert_held(&wil->mutex);
899 
900 	if (!vring->va)
901 		return;
902 
903 	wil_dbg_misc(wil, "%s() id=%d\n", __func__, id);
904 
905 	spin_lock_bh(&txdata->lock);
906 	txdata->dot1x_open = false;
907 	txdata->enabled = 0; /* no Tx can be in progress or start anew */
908 	spin_unlock_bh(&txdata->lock);
909 	/* make sure NAPI won't touch this vring */
910 	if (test_bit(wil_status_napi_en, wil->status))
911 		napi_synchronize(&wil->napi_tx);
912 
913 	wil_vring_free(wil, vring, 1);
914 }
915 
916 static struct vring *wil_find_tx_ucast(struct wil6210_priv *wil,
917 				       struct sk_buff *skb)
918 {
919 	int i;
920 	struct ethhdr *eth = (void *)skb->data;
921 	int cid = wil_find_cid(wil, eth->h_dest);
922 
923 	if (cid < 0)
924 		return NULL;
925 
926 	/* TODO: fix for multiple TID */
927 	for (i = 0; i < ARRAY_SIZE(wil->vring2cid_tid); i++) {
928 		if (!wil->vring_tx_data[i].dot1x_open &&
929 		    (skb->protocol != cpu_to_be16(ETH_P_PAE)))
930 			continue;
931 		if (wil->vring2cid_tid[i][0] == cid) {
932 			struct vring *v = &wil->vring_tx[i];
933 			struct vring_tx_data *txdata = &wil->vring_tx_data[i];
934 
935 			wil_dbg_txrx(wil, "%s(%pM) -> [%d]\n",
936 				     __func__, eth->h_dest, i);
937 			if (v->va && txdata->enabled) {
938 				return v;
939 			} else {
940 				wil_dbg_txrx(wil, "vring[%d] not valid\n", i);
941 				return NULL;
942 			}
943 		}
944 	}
945 
946 	return NULL;
947 }
948 
949 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
950 			struct sk_buff *skb);
951 
952 static struct vring *wil_find_tx_vring_sta(struct wil6210_priv *wil,
953 					   struct sk_buff *skb)
954 {
955 	struct vring *v;
956 	int i;
957 	u8 cid;
958 	struct vring_tx_data *txdata;
959 
960 	/* In the STA mode, it is expected to have only 1 VRING
961 	 * for the AP we connected to.
962 	 * find 1-st vring eligible for this skb and use it.
963 	 */
964 	for (i = 0; i < WIL6210_MAX_TX_RINGS; i++) {
965 		v = &wil->vring_tx[i];
966 		txdata = &wil->vring_tx_data[i];
967 		if (!v->va || !txdata->enabled)
968 			continue;
969 
970 		cid = wil->vring2cid_tid[i][0];
971 		if (cid >= WIL6210_MAX_CID) /* skip BCAST */
972 			continue;
973 
974 		if (!wil->vring_tx_data[i].dot1x_open &&
975 		    (skb->protocol != cpu_to_be16(ETH_P_PAE)))
976 			continue;
977 
978 		wil_dbg_txrx(wil, "Tx -> ring %d\n", i);
979 
980 		return v;
981 	}
982 
983 	wil_dbg_txrx(wil, "Tx while no vrings active?\n");
984 
985 	return NULL;
986 }
987 
988 /* Use one of 2 strategies:
989  *
990  * 1. New (real broadcast):
991  *    use dedicated broadcast vring
992  * 2. Old (pseudo-DMS):
993  *    Find 1-st vring and return it;
994  *    duplicate skb and send it to other active vrings;
995  *    in all cases override dest address to unicast peer's address
996  * Use old strategy when new is not supported yet:
997  *  - for PBSS
998  */
999 static struct vring *wil_find_tx_bcast_1(struct wil6210_priv *wil,
1000 					 struct sk_buff *skb)
1001 {
1002 	struct vring *v;
1003 	struct vring_tx_data *txdata;
1004 	int i = wil->bcast_vring;
1005 
1006 	if (i < 0)
1007 		return NULL;
1008 	v = &wil->vring_tx[i];
1009 	txdata = &wil->vring_tx_data[i];
1010 	if (!v->va || !txdata->enabled)
1011 		return NULL;
1012 	if (!wil->vring_tx_data[i].dot1x_open &&
1013 	    (skb->protocol != cpu_to_be16(ETH_P_PAE)))
1014 		return NULL;
1015 
1016 	return v;
1017 }
1018 
1019 static void wil_set_da_for_vring(struct wil6210_priv *wil,
1020 				 struct sk_buff *skb, int vring_index)
1021 {
1022 	struct ethhdr *eth = (void *)skb->data;
1023 	int cid = wil->vring2cid_tid[vring_index][0];
1024 
1025 	ether_addr_copy(eth->h_dest, wil->sta[cid].addr);
1026 }
1027 
1028 static struct vring *wil_find_tx_bcast_2(struct wil6210_priv *wil,
1029 					 struct sk_buff *skb)
1030 {
1031 	struct vring *v, *v2;
1032 	struct sk_buff *skb2;
1033 	int i;
1034 	u8 cid;
1035 	struct ethhdr *eth = (void *)skb->data;
1036 	char *src = eth->h_source;
1037 	struct vring_tx_data *txdata;
1038 
1039 	/* find 1-st vring eligible for data */
1040 	for (i = 0; i < WIL6210_MAX_TX_RINGS; i++) {
1041 		v = &wil->vring_tx[i];
1042 		txdata = &wil->vring_tx_data[i];
1043 		if (!v->va || !txdata->enabled)
1044 			continue;
1045 
1046 		cid = wil->vring2cid_tid[i][0];
1047 		if (cid >= WIL6210_MAX_CID) /* skip BCAST */
1048 			continue;
1049 		if (!wil->vring_tx_data[i].dot1x_open &&
1050 		    (skb->protocol != cpu_to_be16(ETH_P_PAE)))
1051 			continue;
1052 
1053 		/* don't Tx back to source when re-routing Rx->Tx at the AP */
1054 		if (0 == memcmp(wil->sta[cid].addr, src, ETH_ALEN))
1055 			continue;
1056 
1057 		goto found;
1058 	}
1059 
1060 	wil_dbg_txrx(wil, "Tx while no vrings active?\n");
1061 
1062 	return NULL;
1063 
1064 found:
1065 	wil_dbg_txrx(wil, "BCAST -> ring %d\n", i);
1066 	wil_set_da_for_vring(wil, skb, i);
1067 
1068 	/* find other active vrings and duplicate skb for each */
1069 	for (i++; i < WIL6210_MAX_TX_RINGS; i++) {
1070 		v2 = &wil->vring_tx[i];
1071 		if (!v2->va)
1072 			continue;
1073 		cid = wil->vring2cid_tid[i][0];
1074 		if (cid >= WIL6210_MAX_CID) /* skip BCAST */
1075 			continue;
1076 		if (!wil->vring_tx_data[i].dot1x_open &&
1077 		    (skb->protocol != cpu_to_be16(ETH_P_PAE)))
1078 			continue;
1079 
1080 		if (0 == memcmp(wil->sta[cid].addr, src, ETH_ALEN))
1081 			continue;
1082 
1083 		skb2 = skb_copy(skb, GFP_ATOMIC);
1084 		if (skb2) {
1085 			wil_dbg_txrx(wil, "BCAST DUP -> ring %d\n", i);
1086 			wil_set_da_for_vring(wil, skb2, i);
1087 			wil_tx_vring(wil, v2, skb2);
1088 		} else {
1089 			wil_err(wil, "skb_copy failed\n");
1090 		}
1091 	}
1092 
1093 	return v;
1094 }
1095 
1096 static struct vring *wil_find_tx_bcast(struct wil6210_priv *wil,
1097 				       struct sk_buff *skb)
1098 {
1099 	struct wireless_dev *wdev = wil->wdev;
1100 
1101 	if (wdev->iftype != NL80211_IFTYPE_AP)
1102 		return wil_find_tx_bcast_2(wil, skb);
1103 
1104 	return wil_find_tx_bcast_1(wil, skb);
1105 }
1106 
1107 static int wil_tx_desc_map(struct vring_tx_desc *d, dma_addr_t pa, u32 len,
1108 			   int vring_index)
1109 {
1110 	wil_desc_addr_set(&d->dma.addr, pa);
1111 	d->dma.ip_length = 0;
1112 	/* 0..6: mac_length; 7:ip_version 0-IP6 1-IP4*/
1113 	d->dma.b11 = 0/*14 | BIT(7)*/;
1114 	d->dma.error = 0;
1115 	d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
1116 	d->dma.length = cpu_to_le16((u16)len);
1117 	d->dma.d0 = (vring_index << DMA_CFG_DESC_TX_0_QID_POS);
1118 	d->mac.d[0] = 0;
1119 	d->mac.d[1] = 0;
1120 	d->mac.d[2] = 0;
1121 	d->mac.ucode_cmd = 0;
1122 	/* translation type:  0 - bypass; 1 - 802.3; 2 - native wifi */
1123 	d->mac.d[2] = BIT(MAC_CFG_DESC_TX_2_SNAP_HDR_INSERTION_EN_POS) |
1124 		      (1 << MAC_CFG_DESC_TX_2_L2_TRANSLATION_TYPE_POS);
1125 
1126 	return 0;
1127 }
1128 
1129 static inline
1130 void wil_tx_desc_set_nr_frags(struct vring_tx_desc *d, int nr_frags)
1131 {
1132 	d->mac.d[2] |= (nr_frags << MAC_CFG_DESC_TX_2_NUM_OF_DESCRIPTORS_POS);
1133 }
1134 
1135 /**
1136  * Sets the descriptor @d up for csum and/or TSO offloading. The corresponding
1137  * @skb is used to obtain the protocol and headers length.
1138  * @tso_desc_type is a descriptor type for TSO: 0 - a header, 1 - first data,
1139  * 2 - middle, 3 - last descriptor.
1140  */
1141 
1142 static void wil_tx_desc_offload_setup_tso(struct vring_tx_desc *d,
1143 					  struct sk_buff *skb,
1144 					  int tso_desc_type, bool is_ipv4,
1145 					  int tcp_hdr_len, int skb_net_hdr_len)
1146 {
1147 	d->dma.b11 = ETH_HLEN; /* MAC header length */
1148 	d->dma.b11 |= is_ipv4 << DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_POS;
1149 
1150 	d->dma.d0 |= (2 << DMA_CFG_DESC_TX_0_L4_TYPE_POS);
1151 	/* L4 header len: TCP header length */
1152 	d->dma.d0 |= (tcp_hdr_len & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
1153 
1154 	/* Setup TSO: bit and desc type */
1155 	d->dma.d0 |= (BIT(DMA_CFG_DESC_TX_0_TCP_SEG_EN_POS)) |
1156 		(tso_desc_type << DMA_CFG_DESC_TX_0_SEGMENT_BUF_DETAILS_POS);
1157 	d->dma.d0 |= (is_ipv4 << DMA_CFG_DESC_TX_0_IPV4_CHECKSUM_EN_POS);
1158 
1159 	d->dma.ip_length = skb_net_hdr_len;
1160 	/* Enable TCP/UDP checksum */
1161 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_TCP_UDP_CHECKSUM_EN_POS);
1162 	/* Calculate pseudo-header */
1163 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_PSEUDO_HEADER_CALC_EN_POS);
1164 }
1165 
1166 /**
1167  * Sets the descriptor @d up for csum. The corresponding
1168  * @skb is used to obtain the protocol and headers length.
1169  * Returns the protocol: 0 - not TCP, 1 - TCPv4, 2 - TCPv6.
1170  * Note, if d==NULL, the function only returns the protocol result.
1171  *
1172  * It is very similar to previous wil_tx_desc_offload_setup_tso. This
1173  * is "if unrolling" to optimize the critical path.
1174  */
1175 
1176 static int wil_tx_desc_offload_setup(struct vring_tx_desc *d,
1177 				     struct sk_buff *skb){
1178 	int protocol;
1179 
1180 	if (skb->ip_summed != CHECKSUM_PARTIAL)
1181 		return 0;
1182 
1183 	d->dma.b11 = ETH_HLEN; /* MAC header length */
1184 
1185 	switch (skb->protocol) {
1186 	case cpu_to_be16(ETH_P_IP):
1187 		protocol = ip_hdr(skb)->protocol;
1188 		d->dma.b11 |= BIT(DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_POS);
1189 		break;
1190 	case cpu_to_be16(ETH_P_IPV6):
1191 		protocol = ipv6_hdr(skb)->nexthdr;
1192 		break;
1193 	default:
1194 		return -EINVAL;
1195 	}
1196 
1197 	switch (protocol) {
1198 	case IPPROTO_TCP:
1199 		d->dma.d0 |= (2 << DMA_CFG_DESC_TX_0_L4_TYPE_POS);
1200 		/* L4 header len: TCP header length */
1201 		d->dma.d0 |=
1202 		(tcp_hdrlen(skb) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
1203 		break;
1204 	case IPPROTO_UDP:
1205 		/* L4 header len: UDP header length */
1206 		d->dma.d0 |=
1207 		(sizeof(struct udphdr) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
1208 		break;
1209 	default:
1210 		return -EINVAL;
1211 	}
1212 
1213 	d->dma.ip_length = skb_network_header_len(skb);
1214 	/* Enable TCP/UDP checksum */
1215 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_TCP_UDP_CHECKSUM_EN_POS);
1216 	/* Calculate pseudo-header */
1217 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_PSEUDO_HEADER_CALC_EN_POS);
1218 
1219 	return 0;
1220 }
1221 
1222 static inline void wil_tx_last_desc(struct vring_tx_desc *d)
1223 {
1224 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_EOP_POS) |
1225 	      BIT(DMA_CFG_DESC_TX_0_CMD_MARK_WB_POS) |
1226 	      BIT(DMA_CFG_DESC_TX_0_CMD_DMA_IT_POS);
1227 }
1228 
1229 static inline void wil_set_tx_desc_last_tso(volatile struct vring_tx_desc *d)
1230 {
1231 	d->dma.d0 |= wil_tso_type_lst <<
1232 		  DMA_CFG_DESC_TX_0_SEGMENT_BUF_DETAILS_POS;
1233 }
1234 
1235 static int __wil_tx_vring_tso(struct wil6210_priv *wil, struct vring *vring,
1236 			      struct sk_buff *skb)
1237 {
1238 	struct device *dev = wil_to_dev(wil);
1239 
1240 	/* point to descriptors in shared memory */
1241 	volatile struct vring_tx_desc *_desc = NULL, *_hdr_desc,
1242 				      *_first_desc = NULL;
1243 
1244 	/* pointers to shadow descriptors */
1245 	struct vring_tx_desc desc_mem, hdr_desc_mem, first_desc_mem,
1246 			     *d = &hdr_desc_mem, *hdr_desc = &hdr_desc_mem,
1247 			     *first_desc = &first_desc_mem;
1248 
1249 	/* pointer to shadow descriptors' context */
1250 	struct wil_ctx *hdr_ctx, *first_ctx = NULL;
1251 
1252 	int descs_used = 0; /* total number of used descriptors */
1253 	int sg_desc_cnt = 0; /* number of descriptors for current mss*/
1254 
1255 	u32 swhead = vring->swhead;
1256 	int used, avail = wil_vring_avail_tx(vring);
1257 	int nr_frags = skb_shinfo(skb)->nr_frags;
1258 	int min_desc_required = nr_frags + 1;
1259 	int mss = skb_shinfo(skb)->gso_size;	/* payload size w/o headers */
1260 	int f, len, hdrlen, headlen;
1261 	int vring_index = vring - wil->vring_tx;
1262 	struct vring_tx_data *txdata = &wil->vring_tx_data[vring_index];
1263 	uint i = swhead;
1264 	dma_addr_t pa;
1265 	const skb_frag_t *frag = NULL;
1266 	int rem_data = mss;
1267 	int lenmss;
1268 	int hdr_compensation_need = true;
1269 	int desc_tso_type = wil_tso_type_first;
1270 	bool is_ipv4;
1271 	int tcp_hdr_len;
1272 	int skb_net_hdr_len;
1273 	int gso_type;
1274 	int rc = -EINVAL;
1275 
1276 	wil_dbg_txrx(wil, "%s() %d bytes to vring %d\n",
1277 		     __func__, skb->len, vring_index);
1278 
1279 	if (unlikely(!txdata->enabled))
1280 		return -EINVAL;
1281 
1282 	/* A typical page 4K is 3-4 payloads, we assume each fragment
1283 	 * is a full payload, that's how min_desc_required has been
1284 	 * calculated. In real we might need more or less descriptors,
1285 	 * this is the initial check only.
1286 	 */
1287 	if (unlikely(avail < min_desc_required)) {
1288 		wil_err_ratelimited(wil,
1289 				    "TSO: Tx ring[%2d] full. No space for %d fragments\n",
1290 				    vring_index, min_desc_required);
1291 		return -ENOMEM;
1292 	}
1293 
1294 	/* Header Length = MAC header len + IP header len + TCP header len*/
1295 	hdrlen = ETH_HLEN +
1296 		(int)skb_network_header_len(skb) +
1297 		tcp_hdrlen(skb);
1298 
1299 	gso_type = skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV6 | SKB_GSO_TCPV4);
1300 	switch (gso_type) {
1301 	case SKB_GSO_TCPV4:
1302 		/* TCP v4, zero out the IP length and IPv4 checksum fields
1303 		 * as required by the offloading doc
1304 		 */
1305 		ip_hdr(skb)->tot_len = 0;
1306 		ip_hdr(skb)->check = 0;
1307 		is_ipv4 = true;
1308 		break;
1309 	case SKB_GSO_TCPV6:
1310 		/* TCP v6, zero out the payload length */
1311 		ipv6_hdr(skb)->payload_len = 0;
1312 		is_ipv4 = false;
1313 		break;
1314 	default:
1315 		/* other than TCPv4 or TCPv6 types are not supported for TSO.
1316 		 * It is also illegal for both to be set simultaneously
1317 		 */
1318 		return -EINVAL;
1319 	}
1320 
1321 	if (skb->ip_summed != CHECKSUM_PARTIAL)
1322 		return -EINVAL;
1323 
1324 	/* tcp header length and skb network header length are fixed for all
1325 	 * packet's descriptors - read then once here
1326 	 */
1327 	tcp_hdr_len = tcp_hdrlen(skb);
1328 	skb_net_hdr_len = skb_network_header_len(skb);
1329 
1330 	_hdr_desc = &vring->va[i].tx;
1331 
1332 	pa = dma_map_single(dev, skb->data, hdrlen, DMA_TO_DEVICE);
1333 	if (unlikely(dma_mapping_error(dev, pa))) {
1334 		wil_err(wil, "TSO: Skb head DMA map error\n");
1335 		goto err_exit;
1336 	}
1337 
1338 	wil_tx_desc_map(hdr_desc, pa, hdrlen, vring_index);
1339 	wil_tx_desc_offload_setup_tso(hdr_desc, skb, wil_tso_type_hdr, is_ipv4,
1340 				      tcp_hdr_len, skb_net_hdr_len);
1341 	wil_tx_last_desc(hdr_desc);
1342 
1343 	vring->ctx[i].mapped_as = wil_mapped_as_single;
1344 	hdr_ctx = &vring->ctx[i];
1345 
1346 	descs_used++;
1347 	headlen = skb_headlen(skb) - hdrlen;
1348 
1349 	for (f = headlen ? -1 : 0; f < nr_frags; f++)  {
1350 		if (headlen) {
1351 			len = headlen;
1352 			wil_dbg_txrx(wil, "TSO: process skb head, len %u\n",
1353 				     len);
1354 		} else {
1355 			frag = &skb_shinfo(skb)->frags[f];
1356 			len = frag->size;
1357 			wil_dbg_txrx(wil, "TSO: frag[%d]: len %u\n", f, len);
1358 		}
1359 
1360 		while (len) {
1361 			wil_dbg_txrx(wil,
1362 				     "TSO: len %d, rem_data %d, descs_used %d\n",
1363 				     len, rem_data, descs_used);
1364 
1365 			if (descs_used == avail)  {
1366 				wil_err_ratelimited(wil, "TSO: ring overflow\n");
1367 				rc = -ENOMEM;
1368 				goto mem_error;
1369 			}
1370 
1371 			lenmss = min_t(int, rem_data, len);
1372 			i = (swhead + descs_used) % vring->size;
1373 			wil_dbg_txrx(wil, "TSO: lenmss %d, i %d\n", lenmss, i);
1374 
1375 			if (!headlen) {
1376 				pa = skb_frag_dma_map(dev, frag,
1377 						      frag->size - len, lenmss,
1378 						      DMA_TO_DEVICE);
1379 				vring->ctx[i].mapped_as = wil_mapped_as_page;
1380 			} else {
1381 				pa = dma_map_single(dev,
1382 						    skb->data +
1383 						    skb_headlen(skb) - headlen,
1384 						    lenmss,
1385 						    DMA_TO_DEVICE);
1386 				vring->ctx[i].mapped_as = wil_mapped_as_single;
1387 				headlen -= lenmss;
1388 			}
1389 
1390 			if (unlikely(dma_mapping_error(dev, pa))) {
1391 				wil_err(wil, "TSO: DMA map page error\n");
1392 				goto mem_error;
1393 			}
1394 
1395 			_desc = &vring->va[i].tx;
1396 
1397 			if (!_first_desc) {
1398 				_first_desc = _desc;
1399 				first_ctx = &vring->ctx[i];
1400 				d = first_desc;
1401 			} else {
1402 				d = &desc_mem;
1403 			}
1404 
1405 			wil_tx_desc_map(d, pa, lenmss, vring_index);
1406 			wil_tx_desc_offload_setup_tso(d, skb, desc_tso_type,
1407 						      is_ipv4, tcp_hdr_len,
1408 						      skb_net_hdr_len);
1409 
1410 			/* use tso_type_first only once */
1411 			desc_tso_type = wil_tso_type_mid;
1412 
1413 			descs_used++;  /* desc used so far */
1414 			sg_desc_cnt++; /* desc used for this segment */
1415 			len -= lenmss;
1416 			rem_data -= lenmss;
1417 
1418 			wil_dbg_txrx(wil,
1419 				     "TSO: len %d, rem_data %d, descs_used %d, sg_desc_cnt %d,\n",
1420 				     len, rem_data, descs_used, sg_desc_cnt);
1421 
1422 			/* Close the segment if reached mss size or last frag*/
1423 			if (rem_data == 0 || (f == nr_frags - 1 && len == 0)) {
1424 				if (hdr_compensation_need) {
1425 					/* first segment include hdr desc for
1426 					 * release
1427 					 */
1428 					hdr_ctx->nr_frags = sg_desc_cnt;
1429 					wil_tx_desc_set_nr_frags(first_desc,
1430 								 sg_desc_cnt +
1431 								 1);
1432 					hdr_compensation_need = false;
1433 				} else {
1434 					wil_tx_desc_set_nr_frags(first_desc,
1435 								 sg_desc_cnt);
1436 				}
1437 				first_ctx->nr_frags = sg_desc_cnt - 1;
1438 
1439 				wil_tx_last_desc(d);
1440 
1441 				/* first descriptor may also be the last
1442 				 * for this mss - make sure not to copy
1443 				 * it twice
1444 				 */
1445 				if (first_desc != d)
1446 					*_first_desc = *first_desc;
1447 
1448 				/*last descriptor will be copied at the end
1449 				 * of this TS processing
1450 				 */
1451 				if (f < nr_frags - 1 || len > 0)
1452 					*_desc = *d;
1453 
1454 				rem_data = mss;
1455 				_first_desc = NULL;
1456 				sg_desc_cnt = 0;
1457 			} else if (first_desc != d) /* update mid descriptor */
1458 					*_desc = *d;
1459 		}
1460 	}
1461 
1462 	/* first descriptor may also be the last.
1463 	 * in this case d pointer is invalid
1464 	 */
1465 	if (_first_desc == _desc)
1466 		d = first_desc;
1467 
1468 	/* Last data descriptor */
1469 	wil_set_tx_desc_last_tso(d);
1470 	*_desc = *d;
1471 
1472 	/* Fill the total number of descriptors in first desc (hdr)*/
1473 	wil_tx_desc_set_nr_frags(hdr_desc, descs_used);
1474 	*_hdr_desc = *hdr_desc;
1475 
1476 	/* hold reference to skb
1477 	 * to prevent skb release before accounting
1478 	 * in case of immediate "tx done"
1479 	 */
1480 	vring->ctx[i].skb = skb_get(skb);
1481 
1482 	/* performance monitoring */
1483 	used = wil_vring_used_tx(vring);
1484 	if (wil_val_in_range(vring_idle_trsh,
1485 			     used, used + descs_used)) {
1486 		txdata->idle += get_cycles() - txdata->last_idle;
1487 		wil_dbg_txrx(wil,  "Ring[%2d] not idle %d -> %d\n",
1488 			     vring_index, used, used + descs_used);
1489 	}
1490 
1491 	/* advance swhead */
1492 	wil_vring_advance_head(vring, descs_used);
1493 	wil_dbg_txrx(wil, "TSO: Tx swhead %d -> %d\n", swhead, vring->swhead);
1494 
1495 	/* make sure all writes to descriptors (shared memory) are done before
1496 	 * committing them to HW
1497 	 */
1498 	wmb();
1499 
1500 	wil_w(wil, vring->hwtail, vring->swhead);
1501 	return 0;
1502 
1503 mem_error:
1504 	while (descs_used > 0) {
1505 		struct wil_ctx *ctx;
1506 
1507 		i = (swhead + descs_used) % vring->size;
1508 		d = (struct vring_tx_desc *)&vring->va[i].tx;
1509 		_desc = &vring->va[i].tx;
1510 		*d = *_desc;
1511 		_desc->dma.status = TX_DMA_STATUS_DU;
1512 		ctx = &vring->ctx[i];
1513 		wil_txdesc_unmap(dev, d, ctx);
1514 		memset(ctx, 0, sizeof(*ctx));
1515 		descs_used--;
1516 	}
1517 err_exit:
1518 	return rc;
1519 }
1520 
1521 static int __wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
1522 			  struct sk_buff *skb)
1523 {
1524 	struct device *dev = wil_to_dev(wil);
1525 	struct vring_tx_desc dd, *d = &dd;
1526 	volatile struct vring_tx_desc *_d;
1527 	u32 swhead = vring->swhead;
1528 	int avail = wil_vring_avail_tx(vring);
1529 	int nr_frags = skb_shinfo(skb)->nr_frags;
1530 	uint f = 0;
1531 	int vring_index = vring - wil->vring_tx;
1532 	struct vring_tx_data *txdata = &wil->vring_tx_data[vring_index];
1533 	uint i = swhead;
1534 	dma_addr_t pa;
1535 	int used;
1536 	bool mcast = (vring_index == wil->bcast_vring);
1537 	uint len = skb_headlen(skb);
1538 
1539 	wil_dbg_txrx(wil, "%s() %d bytes to vring %d\n",
1540 		     __func__, skb->len, vring_index);
1541 
1542 	if (unlikely(!txdata->enabled))
1543 		return -EINVAL;
1544 
1545 	if (unlikely(avail < 1 + nr_frags)) {
1546 		wil_err_ratelimited(wil,
1547 				    "Tx ring[%2d] full. No space for %d fragments\n",
1548 				    vring_index, 1 + nr_frags);
1549 		return -ENOMEM;
1550 	}
1551 	_d = &vring->va[i].tx;
1552 
1553 	pa = dma_map_single(dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
1554 
1555 	wil_dbg_txrx(wil, "Tx[%2d] skb %d bytes 0x%p -> %pad\n", vring_index,
1556 		     skb_headlen(skb), skb->data, &pa);
1557 	wil_hex_dump_txrx("Tx ", DUMP_PREFIX_OFFSET, 16, 1,
1558 			  skb->data, skb_headlen(skb), false);
1559 
1560 	if (unlikely(dma_mapping_error(dev, pa)))
1561 		return -EINVAL;
1562 	vring->ctx[i].mapped_as = wil_mapped_as_single;
1563 	/* 1-st segment */
1564 	wil_tx_desc_map(d, pa, len, vring_index);
1565 	if (unlikely(mcast)) {
1566 		d->mac.d[0] |= BIT(MAC_CFG_DESC_TX_0_MCS_EN_POS); /* MCS 0 */
1567 		if (unlikely(len > WIL_BCAST_MCS0_LIMIT)) /* set MCS 1 */
1568 			d->mac.d[0] |= (1 << MAC_CFG_DESC_TX_0_MCS_INDEX_POS);
1569 	}
1570 	/* Process TCP/UDP checksum offloading */
1571 	if (unlikely(wil_tx_desc_offload_setup(d, skb))) {
1572 		wil_err(wil, "Tx[%2d] Failed to set cksum, drop packet\n",
1573 			vring_index);
1574 		goto dma_error;
1575 	}
1576 
1577 	vring->ctx[i].nr_frags = nr_frags;
1578 	wil_tx_desc_set_nr_frags(d, nr_frags + 1);
1579 
1580 	/* middle segments */
1581 	for (; f < nr_frags; f++) {
1582 		const struct skb_frag_struct *frag =
1583 				&skb_shinfo(skb)->frags[f];
1584 		int len = skb_frag_size(frag);
1585 
1586 		*_d = *d;
1587 		wil_dbg_txrx(wil, "Tx[%2d] desc[%4d]\n", vring_index, i);
1588 		wil_hex_dump_txrx("TxD ", DUMP_PREFIX_NONE, 32, 4,
1589 				  (const void *)d, sizeof(*d), false);
1590 		i = (swhead + f + 1) % vring->size;
1591 		_d = &vring->va[i].tx;
1592 		pa = skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag),
1593 				      DMA_TO_DEVICE);
1594 		if (unlikely(dma_mapping_error(dev, pa))) {
1595 			wil_err(wil, "Tx[%2d] failed to map fragment\n",
1596 				vring_index);
1597 			goto dma_error;
1598 		}
1599 		vring->ctx[i].mapped_as = wil_mapped_as_page;
1600 		wil_tx_desc_map(d, pa, len, vring_index);
1601 		/* no need to check return code -
1602 		 * if it succeeded for 1-st descriptor,
1603 		 * it will succeed here too
1604 		 */
1605 		wil_tx_desc_offload_setup(d, skb);
1606 	}
1607 	/* for the last seg only */
1608 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_EOP_POS);
1609 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_MARK_WB_POS);
1610 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_DMA_IT_POS);
1611 	*_d = *d;
1612 	wil_dbg_txrx(wil, "Tx[%2d] desc[%4d]\n", vring_index, i);
1613 	wil_hex_dump_txrx("TxD ", DUMP_PREFIX_NONE, 32, 4,
1614 			  (const void *)d, sizeof(*d), false);
1615 
1616 	/* hold reference to skb
1617 	 * to prevent skb release before accounting
1618 	 * in case of immediate "tx done"
1619 	 */
1620 	vring->ctx[i].skb = skb_get(skb);
1621 
1622 	/* performance monitoring */
1623 	used = wil_vring_used_tx(vring);
1624 	if (wil_val_in_range(vring_idle_trsh,
1625 			     used, used + nr_frags + 1)) {
1626 		txdata->idle += get_cycles() - txdata->last_idle;
1627 		wil_dbg_txrx(wil,  "Ring[%2d] not idle %d -> %d\n",
1628 			     vring_index, used, used + nr_frags + 1);
1629 	}
1630 
1631 	/* advance swhead */
1632 	wil_vring_advance_head(vring, nr_frags + 1);
1633 	wil_dbg_txrx(wil, "Tx[%2d] swhead %d -> %d\n", vring_index, swhead,
1634 		     vring->swhead);
1635 	trace_wil6210_tx(vring_index, swhead, skb->len, nr_frags);
1636 
1637 	/* make sure all writes to descriptors (shared memory) are done before
1638 	 * committing them to HW
1639 	 */
1640 	wmb();
1641 
1642 	wil_w(wil, vring->hwtail, vring->swhead);
1643 
1644 	return 0;
1645  dma_error:
1646 	/* unmap what we have mapped */
1647 	nr_frags = f + 1; /* frags mapped + one for skb head */
1648 	for (f = 0; f < nr_frags; f++) {
1649 		struct wil_ctx *ctx;
1650 
1651 		i = (swhead + f) % vring->size;
1652 		ctx = &vring->ctx[i];
1653 		_d = &vring->va[i].tx;
1654 		*d = *_d;
1655 		_d->dma.status = TX_DMA_STATUS_DU;
1656 		wil_txdesc_unmap(dev, d, ctx);
1657 
1658 		memset(ctx, 0, sizeof(*ctx));
1659 	}
1660 
1661 	return -EINVAL;
1662 }
1663 
1664 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
1665 			struct sk_buff *skb)
1666 {
1667 	int vring_index = vring - wil->vring_tx;
1668 	struct vring_tx_data *txdata = &wil->vring_tx_data[vring_index];
1669 	int rc;
1670 
1671 	spin_lock(&txdata->lock);
1672 
1673 	rc = (skb_is_gso(skb) ? __wil_tx_vring_tso : __wil_tx_vring)
1674 	     (wil, vring, skb);
1675 
1676 	spin_unlock(&txdata->lock);
1677 
1678 	return rc;
1679 }
1680 
1681 netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
1682 {
1683 	struct wil6210_priv *wil = ndev_to_wil(ndev);
1684 	struct ethhdr *eth = (void *)skb->data;
1685 	bool bcast = is_multicast_ether_addr(eth->h_dest);
1686 	struct vring *vring;
1687 	static bool pr_once_fw;
1688 	int rc;
1689 
1690 	wil_dbg_txrx(wil, "%s()\n", __func__);
1691 	if (unlikely(!test_bit(wil_status_fwready, wil->status))) {
1692 		if (!pr_once_fw) {
1693 			wil_err(wil, "FW not ready\n");
1694 			pr_once_fw = true;
1695 		}
1696 		goto drop;
1697 	}
1698 	if (unlikely(!test_bit(wil_status_fwconnected, wil->status))) {
1699 		wil_err_ratelimited(wil, "FW not connected\n");
1700 		goto drop;
1701 	}
1702 	if (unlikely(wil->wdev->iftype == NL80211_IFTYPE_MONITOR)) {
1703 		wil_err(wil, "Xmit in monitor mode not supported\n");
1704 		goto drop;
1705 	}
1706 	pr_once_fw = false;
1707 
1708 	/* find vring */
1709 	if (wil->wdev->iftype == NL80211_IFTYPE_STATION) {
1710 		/* in STA mode (ESS), all to same VRING */
1711 		vring = wil_find_tx_vring_sta(wil, skb);
1712 	} else { /* direct communication, find matching VRING */
1713 		vring = bcast ? wil_find_tx_bcast(wil, skb) :
1714 				wil_find_tx_ucast(wil, skb);
1715 	}
1716 	if (unlikely(!vring)) {
1717 		wil_dbg_txrx(wil, "No Tx VRING found for %pM\n", eth->h_dest);
1718 		goto drop;
1719 	}
1720 	/* set up vring entry */
1721 	rc = wil_tx_vring(wil, vring, skb);
1722 
1723 	/* do we still have enough room in the vring? */
1724 	if (unlikely(wil_vring_avail_tx(vring) < wil_vring_wmark_low(vring))) {
1725 		netif_tx_stop_all_queues(wil_to_ndev(wil));
1726 		wil_dbg_txrx(wil, "netif_tx_stop : ring full\n");
1727 	}
1728 
1729 	switch (rc) {
1730 	case 0:
1731 		/* statistics will be updated on the tx_complete */
1732 		dev_kfree_skb_any(skb);
1733 		return NETDEV_TX_OK;
1734 	case -ENOMEM:
1735 		return NETDEV_TX_BUSY;
1736 	default:
1737 		break; /* goto drop; */
1738 	}
1739  drop:
1740 	ndev->stats.tx_dropped++;
1741 	dev_kfree_skb_any(skb);
1742 
1743 	return NET_XMIT_DROP;
1744 }
1745 
1746 static inline bool wil_need_txstat(struct sk_buff *skb)
1747 {
1748 	struct ethhdr *eth = (void *)skb->data;
1749 
1750 	return is_unicast_ether_addr(eth->h_dest) && skb->sk &&
1751 	       (skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS);
1752 }
1753 
1754 static inline void wil_consume_skb(struct sk_buff *skb, bool acked)
1755 {
1756 	if (unlikely(wil_need_txstat(skb)))
1757 		skb_complete_wifi_ack(skb, acked);
1758 	else
1759 		acked ? dev_consume_skb_any(skb) : dev_kfree_skb_any(skb);
1760 }
1761 
1762 /**
1763  * Clean up transmitted skb's from the Tx VRING
1764  *
1765  * Return number of descriptors cleared
1766  *
1767  * Safe to call from IRQ
1768  */
1769 int wil_tx_complete(struct wil6210_priv *wil, int ringid)
1770 {
1771 	struct net_device *ndev = wil_to_ndev(wil);
1772 	struct device *dev = wil_to_dev(wil);
1773 	struct vring *vring = &wil->vring_tx[ringid];
1774 	struct vring_tx_data *txdata = &wil->vring_tx_data[ringid];
1775 	int done = 0;
1776 	int cid = wil->vring2cid_tid[ringid][0];
1777 	struct wil_net_stats *stats = NULL;
1778 	volatile struct vring_tx_desc *_d;
1779 	int used_before_complete;
1780 	int used_new;
1781 
1782 	if (unlikely(!vring->va)) {
1783 		wil_err(wil, "Tx irq[%d]: vring not initialized\n", ringid);
1784 		return 0;
1785 	}
1786 
1787 	if (unlikely(!txdata->enabled)) {
1788 		wil_info(wil, "Tx irq[%d]: vring disabled\n", ringid);
1789 		return 0;
1790 	}
1791 
1792 	wil_dbg_txrx(wil, "%s(%d)\n", __func__, ringid);
1793 
1794 	used_before_complete = wil_vring_used_tx(vring);
1795 
1796 	if (cid < WIL6210_MAX_CID)
1797 		stats = &wil->sta[cid].stats;
1798 
1799 	while (!wil_vring_is_empty(vring)) {
1800 		int new_swtail;
1801 		struct wil_ctx *ctx = &vring->ctx[vring->swtail];
1802 		/**
1803 		 * For the fragmented skb, HW will set DU bit only for the
1804 		 * last fragment. look for it.
1805 		 * In TSO the first DU will include hdr desc
1806 		 */
1807 		int lf = (vring->swtail + ctx->nr_frags) % vring->size;
1808 		/* TODO: check we are not past head */
1809 
1810 		_d = &vring->va[lf].tx;
1811 		if (unlikely(!(_d->dma.status & TX_DMA_STATUS_DU)))
1812 			break;
1813 
1814 		new_swtail = (lf + 1) % vring->size;
1815 		while (vring->swtail != new_swtail) {
1816 			struct vring_tx_desc dd, *d = &dd;
1817 			u16 dmalen;
1818 			struct sk_buff *skb;
1819 
1820 			ctx = &vring->ctx[vring->swtail];
1821 			skb = ctx->skb;
1822 			_d = &vring->va[vring->swtail].tx;
1823 
1824 			*d = *_d;
1825 
1826 			dmalen = le16_to_cpu(d->dma.length);
1827 			trace_wil6210_tx_done(ringid, vring->swtail, dmalen,
1828 					      d->dma.error);
1829 			wil_dbg_txrx(wil,
1830 				     "TxC[%2d][%3d] : %d bytes, status 0x%02x err 0x%02x\n",
1831 				     ringid, vring->swtail, dmalen,
1832 				     d->dma.status, d->dma.error);
1833 			wil_hex_dump_txrx("TxCD ", DUMP_PREFIX_NONE, 32, 4,
1834 					  (const void *)d, sizeof(*d), false);
1835 
1836 			wil_txdesc_unmap(dev, d, ctx);
1837 
1838 			if (skb) {
1839 				if (likely(d->dma.error == 0)) {
1840 					ndev->stats.tx_packets++;
1841 					ndev->stats.tx_bytes += skb->len;
1842 					if (stats) {
1843 						stats->tx_packets++;
1844 						stats->tx_bytes += skb->len;
1845 					}
1846 				} else {
1847 					ndev->stats.tx_errors++;
1848 					if (stats)
1849 						stats->tx_errors++;
1850 				}
1851 				wil_consume_skb(skb, d->dma.error == 0);
1852 			}
1853 			memset(ctx, 0, sizeof(*ctx));
1854 			/* There is no need to touch HW descriptor:
1855 			 * - ststus bit TX_DMA_STATUS_DU is set by design,
1856 			 *   so hardware will not try to process this desc.,
1857 			 * - rest of descriptor will be initialized on Tx.
1858 			 */
1859 			vring->swtail = wil_vring_next_tail(vring);
1860 			done++;
1861 		}
1862 	}
1863 
1864 	/* performance monitoring */
1865 	used_new = wil_vring_used_tx(vring);
1866 	if (wil_val_in_range(vring_idle_trsh,
1867 			     used_new, used_before_complete)) {
1868 		wil_dbg_txrx(wil, "Ring[%2d] idle %d -> %d\n",
1869 			     ringid, used_before_complete, used_new);
1870 		txdata->last_idle = get_cycles();
1871 	}
1872 
1873 	if (wil_vring_avail_tx(vring) > wil_vring_wmark_high(vring)) {
1874 		wil_dbg_txrx(wil, "netif_tx_wake : ring not full\n");
1875 		netif_tx_wake_all_queues(wil_to_ndev(wil));
1876 	}
1877 
1878 	return done;
1879 }
1880