xref: /openbmc/linux/drivers/net/wireless/ath/wil6210/txrx.c (revision 6c870213d6f3a25981c10728f46294a3bed1703f)
1 /*
2  * Copyright (c) 2012 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 static inline int wil_vring_is_empty(struct vring *vring)
37 {
38 	return vring->swhead == vring->swtail;
39 }
40 
41 static inline u32 wil_vring_next_tail(struct vring *vring)
42 {
43 	return (vring->swtail + 1) % vring->size;
44 }
45 
46 static inline void wil_vring_advance_head(struct vring *vring, int n)
47 {
48 	vring->swhead = (vring->swhead + n) % vring->size;
49 }
50 
51 static inline int wil_vring_is_full(struct vring *vring)
52 {
53 	return wil_vring_next_tail(vring) == vring->swhead;
54 }
55 /*
56  * Available space in Tx Vring
57  */
58 static inline int wil_vring_avail_tx(struct vring *vring)
59 {
60 	u32 swhead = vring->swhead;
61 	u32 swtail = vring->swtail;
62 	int used = (vring->size + swhead - swtail) % vring->size;
63 
64 	return vring->size - used - 1;
65 }
66 
67 static int wil_vring_alloc(struct wil6210_priv *wil, struct vring *vring)
68 {
69 	struct device *dev = wil_to_dev(wil);
70 	size_t sz = vring->size * sizeof(vring->va[0]);
71 	uint i;
72 
73 	BUILD_BUG_ON(sizeof(vring->va[0]) != 32);
74 
75 	vring->swhead = 0;
76 	vring->swtail = 0;
77 	vring->ctx = kcalloc(vring->size, sizeof(vring->ctx[0]), GFP_KERNEL);
78 	if (!vring->ctx) {
79 		vring->va = NULL;
80 		return -ENOMEM;
81 	}
82 	/*
83 	 * vring->va should be aligned on its size rounded up to power of 2
84 	 * This is granted by the dma_alloc_coherent
85 	 */
86 	vring->va = dma_alloc_coherent(dev, sz, &vring->pa, GFP_KERNEL);
87 	if (!vring->va) {
88 		kfree(vring->ctx);
89 		vring->ctx = NULL;
90 		return -ENOMEM;
91 	}
92 	/* initially, all descriptors are SW owned
93 	 * For Tx and Rx, ownership bit is at the same location, thus
94 	 * we can use any
95 	 */
96 	for (i = 0; i < vring->size; i++) {
97 		volatile struct vring_tx_desc *_d = &(vring->va[i].tx);
98 		_d->dma.status = TX_DMA_STATUS_DU;
99 	}
100 
101 	wil_dbg_misc(wil, "vring[%d] 0x%p:0x%016llx 0x%p\n", vring->size,
102 		     vring->va, (unsigned long long)vring->pa, vring->ctx);
103 
104 	return 0;
105 }
106 
107 static void wil_txdesc_unmap(struct device *dev, struct vring_tx_desc *d,
108 			     struct wil_ctx *ctx)
109 {
110 	dma_addr_t pa = wil_desc_addr(&d->dma.addr);
111 	u16 dmalen = le16_to_cpu(d->dma.length);
112 	switch (ctx->mapped_as) {
113 	case wil_mapped_as_single:
114 		dma_unmap_single(dev, pa, dmalen, DMA_TO_DEVICE);
115 		break;
116 	case wil_mapped_as_page:
117 		dma_unmap_page(dev, pa, dmalen, DMA_TO_DEVICE);
118 		break;
119 	default:
120 		break;
121 	}
122 }
123 
124 static void wil_vring_free(struct wil6210_priv *wil, struct vring *vring,
125 			   int tx)
126 {
127 	struct device *dev = wil_to_dev(wil);
128 	size_t sz = vring->size * sizeof(vring->va[0]);
129 
130 	while (!wil_vring_is_empty(vring)) {
131 		dma_addr_t pa;
132 		u16 dmalen;
133 		struct wil_ctx *ctx;
134 
135 		if (tx) {
136 			struct vring_tx_desc dd, *d = &dd;
137 			volatile struct vring_tx_desc *_d =
138 					&vring->va[vring->swtail].tx;
139 
140 			ctx = &vring->ctx[vring->swtail];
141 			*d = *_d;
142 			wil_txdesc_unmap(dev, d, ctx);
143 			if (ctx->skb)
144 				dev_kfree_skb_any(ctx->skb);
145 			vring->swtail = wil_vring_next_tail(vring);
146 		} else { /* rx */
147 			struct vring_rx_desc dd, *d = &dd;
148 			volatile struct vring_rx_desc *_d =
149 					&vring->va[vring->swhead].rx;
150 
151 			ctx = &vring->ctx[vring->swhead];
152 			*d = *_d;
153 			pa = wil_desc_addr(&d->dma.addr);
154 			dmalen = le16_to_cpu(d->dma.length);
155 			dma_unmap_single(dev, pa, dmalen, DMA_FROM_DEVICE);
156 			kfree_skb(ctx->skb);
157 			wil_vring_advance_head(vring, 1);
158 		}
159 	}
160 	dma_free_coherent(dev, sz, (void *)vring->va, vring->pa);
161 	kfree(vring->ctx);
162 	vring->pa = 0;
163 	vring->va = NULL;
164 	vring->ctx = NULL;
165 }
166 
167 /**
168  * Allocate one skb for Rx VRING
169  *
170  * Safe to call from IRQ
171  */
172 static int wil_vring_alloc_skb(struct wil6210_priv *wil, struct vring *vring,
173 			       u32 i, int headroom)
174 {
175 	struct device *dev = wil_to_dev(wil);
176 	unsigned int sz = RX_BUF_LEN;
177 	struct vring_rx_desc dd, *d = &dd;
178 	volatile struct vring_rx_desc *_d = &(vring->va[i].rx);
179 	dma_addr_t pa;
180 
181 	/* TODO align */
182 	struct sk_buff *skb = dev_alloc_skb(sz + headroom);
183 	if (unlikely(!skb))
184 		return -ENOMEM;
185 
186 	skb_reserve(skb, headroom);
187 	skb_put(skb, sz);
188 
189 	pa = dma_map_single(dev, skb->data, skb->len, DMA_FROM_DEVICE);
190 	if (unlikely(dma_mapping_error(dev, pa))) {
191 		kfree_skb(skb);
192 		return -ENOMEM;
193 	}
194 
195 	d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
196 	wil_desc_addr_set(&d->dma.addr, pa);
197 	/* ip_length don't care */
198 	/* b11 don't care */
199 	/* error don't care */
200 	d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
201 	d->dma.length = cpu_to_le16(sz);
202 	*_d = *d;
203 	vring->ctx[i].skb = skb;
204 
205 	return 0;
206 }
207 
208 /**
209  * Adds radiotap header
210  *
211  * Any error indicated as "Bad FCS"
212  *
213  * Vendor data for 04:ce:14-1 (Wilocity-1) consists of:
214  *  - Rx descriptor: 32 bytes
215  *  - Phy info
216  */
217 static void wil_rx_add_radiotap_header(struct wil6210_priv *wil,
218 				       struct sk_buff *skb)
219 {
220 	struct wireless_dev *wdev = wil->wdev;
221 	struct wil6210_rtap {
222 		struct ieee80211_radiotap_header rthdr;
223 		/* fields should be in the order of bits in rthdr.it_present */
224 		/* flags */
225 		u8 flags;
226 		/* channel */
227 		__le16 chnl_freq __aligned(2);
228 		__le16 chnl_flags;
229 		/* MCS */
230 		u8 mcs_present;
231 		u8 mcs_flags;
232 		u8 mcs_index;
233 	} __packed;
234 	struct wil6210_rtap_vendor {
235 		struct wil6210_rtap rtap;
236 		/* vendor */
237 		u8 vendor_oui[3] __aligned(2);
238 		u8 vendor_ns;
239 		__le16 vendor_skip;
240 		u8 vendor_data[0];
241 	} __packed;
242 	struct vring_rx_desc *d = wil_skb_rxdesc(skb);
243 	struct wil6210_rtap_vendor *rtap_vendor;
244 	int rtap_len = sizeof(struct wil6210_rtap);
245 	int phy_length = 0; /* phy info header size, bytes */
246 	static char phy_data[128];
247 	struct ieee80211_channel *ch = wdev->preset_chandef.chan;
248 
249 	if (rtap_include_phy_info) {
250 		rtap_len = sizeof(*rtap_vendor) + sizeof(*d);
251 		/* calculate additional length */
252 		if (d->dma.status & RX_DMA_STATUS_PHY_INFO) {
253 			/**
254 			 * PHY info starts from 8-byte boundary
255 			 * there are 8-byte lines, last line may be partially
256 			 * written (HW bug), thus FW configures for last line
257 			 * to be excessive. Driver skips this last line.
258 			 */
259 			int len = min_t(int, 8 + sizeof(phy_data),
260 					wil_rxdesc_phy_length(d));
261 			if (len > 8) {
262 				void *p = skb_tail_pointer(skb);
263 				void *pa = PTR_ALIGN(p, 8);
264 				if (skb_tailroom(skb) >= len + (pa - p)) {
265 					phy_length = len - 8;
266 					memcpy(phy_data, pa, phy_length);
267 				}
268 			}
269 		}
270 		rtap_len += phy_length;
271 	}
272 
273 	if (skb_headroom(skb) < rtap_len &&
274 	    pskb_expand_head(skb, rtap_len, 0, GFP_ATOMIC)) {
275 		wil_err(wil, "Unable to expand headrom to %d\n", rtap_len);
276 		return;
277 	}
278 
279 	rtap_vendor = (void *)skb_push(skb, rtap_len);
280 	memset(rtap_vendor, 0, rtap_len);
281 
282 	rtap_vendor->rtap.rthdr.it_version = PKTHDR_RADIOTAP_VERSION;
283 	rtap_vendor->rtap.rthdr.it_len = cpu_to_le16(rtap_len);
284 	rtap_vendor->rtap.rthdr.it_present = cpu_to_le32(
285 			(1 << IEEE80211_RADIOTAP_FLAGS) |
286 			(1 << IEEE80211_RADIOTAP_CHANNEL) |
287 			(1 << IEEE80211_RADIOTAP_MCS));
288 	if (d->dma.status & RX_DMA_STATUS_ERROR)
289 		rtap_vendor->rtap.flags |= IEEE80211_RADIOTAP_F_BADFCS;
290 
291 	rtap_vendor->rtap.chnl_freq = cpu_to_le16(ch ? ch->center_freq : 58320);
292 	rtap_vendor->rtap.chnl_flags = cpu_to_le16(0);
293 
294 	rtap_vendor->rtap.mcs_present = IEEE80211_RADIOTAP_MCS_HAVE_MCS;
295 	rtap_vendor->rtap.mcs_flags = 0;
296 	rtap_vendor->rtap.mcs_index = wil_rxdesc_mcs(d);
297 
298 	if (rtap_include_phy_info) {
299 		rtap_vendor->rtap.rthdr.it_present |= cpu_to_le32(1 <<
300 				IEEE80211_RADIOTAP_VENDOR_NAMESPACE);
301 		/* OUI for Wilocity 04:ce:14 */
302 		rtap_vendor->vendor_oui[0] = 0x04;
303 		rtap_vendor->vendor_oui[1] = 0xce;
304 		rtap_vendor->vendor_oui[2] = 0x14;
305 		rtap_vendor->vendor_ns = 1;
306 		/* Rx descriptor + PHY data  */
307 		rtap_vendor->vendor_skip = cpu_to_le16(sizeof(*d) +
308 						       phy_length);
309 		memcpy(rtap_vendor->vendor_data, (void *)d, sizeof(*d));
310 		memcpy(rtap_vendor->vendor_data + sizeof(*d), phy_data,
311 		       phy_length);
312 	}
313 }
314 
315 /*
316  * Fast swap in place between 2 registers
317  */
318 static void wil_swap_u16(u16 *a, u16 *b)
319 {
320 	*a ^= *b;
321 	*b ^= *a;
322 	*a ^= *b;
323 }
324 
325 static void wil_swap_ethaddr(void *data)
326 {
327 	struct ethhdr *eth = data;
328 	u16 *s = (u16 *)eth->h_source;
329 	u16 *d = (u16 *)eth->h_dest;
330 
331 	wil_swap_u16(s++, d++);
332 	wil_swap_u16(s++, d++);
333 	wil_swap_u16(s, d);
334 }
335 
336 /**
337  * reap 1 frame from @swhead
338  *
339  * Rx descriptor copied to skb->cb
340  *
341  * Safe to call from IRQ
342  */
343 static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
344 					 struct vring *vring)
345 {
346 	struct device *dev = wil_to_dev(wil);
347 	struct net_device *ndev = wil_to_ndev(wil);
348 	volatile struct vring_rx_desc *_d;
349 	struct vring_rx_desc *d;
350 	struct sk_buff *skb;
351 	dma_addr_t pa;
352 	unsigned int sz = RX_BUF_LEN;
353 	u16 dmalen;
354 	u8 ftype;
355 	u8 ds_bits;
356 	int cid;
357 	struct wil_net_stats *stats;
358 
359 
360 	BUILD_BUG_ON(sizeof(struct vring_rx_desc) > sizeof(skb->cb));
361 
362 	if (wil_vring_is_empty(vring))
363 		return NULL;
364 
365 	_d = &(vring->va[vring->swhead].rx);
366 	if (!(_d->dma.status & RX_DMA_STATUS_DU)) {
367 		/* it is not error, we just reached end of Rx done area */
368 		return NULL;
369 	}
370 
371 	skb = vring->ctx[vring->swhead].skb;
372 	d = wil_skb_rxdesc(skb);
373 	*d = *_d;
374 	pa = wil_desc_addr(&d->dma.addr);
375 	vring->ctx[vring->swhead].skb = NULL;
376 	wil_vring_advance_head(vring, 1);
377 
378 	dma_unmap_single(dev, pa, sz, DMA_FROM_DEVICE);
379 	dmalen = le16_to_cpu(d->dma.length);
380 
381 	trace_wil6210_rx(vring->swhead, d);
382 	wil_dbg_txrx(wil, "Rx[%3d] : %d bytes\n", vring->swhead, dmalen);
383 	wil_hex_dump_txrx("Rx ", DUMP_PREFIX_NONE, 32, 4,
384 			  (const void *)d, sizeof(*d), false);
385 
386 	if (dmalen > sz) {
387 		wil_err(wil, "Rx size too large: %d bytes!\n", dmalen);
388 		kfree_skb(skb);
389 		return NULL;
390 	}
391 	skb_trim(skb, dmalen);
392 
393 	prefetch(skb->data);
394 
395 	wil_hex_dump_txrx("Rx ", DUMP_PREFIX_OFFSET, 16, 1,
396 			  skb->data, skb_headlen(skb), false);
397 
398 	cid = wil_rxdesc_cid(d);
399 	stats = &wil->sta[cid].stats;
400 	stats->last_mcs_rx = wil_rxdesc_mcs(d);
401 	wil->stats.last_mcs_rx = stats->last_mcs_rx;
402 
403 	/* use radiotap header only if required */
404 	if (ndev->type == ARPHRD_IEEE80211_RADIOTAP)
405 		wil_rx_add_radiotap_header(wil, skb);
406 
407 	/* no extra checks if in sniffer mode */
408 	if (ndev->type != ARPHRD_ETHER)
409 		return skb;
410 	/*
411 	 * Non-data frames may be delivered through Rx DMA channel (ex: BAR)
412 	 * Driver should recognize it by frame type, that is found
413 	 * in Rx descriptor. If type is not data, it is 802.11 frame as is
414 	 */
415 	ftype = wil_rxdesc_ftype(d) << 2;
416 	if (ftype != IEEE80211_FTYPE_DATA) {
417 		wil_dbg_txrx(wil, "Non-data frame ftype 0x%08x\n", ftype);
418 		/* TODO: process it */
419 		kfree_skb(skb);
420 		return NULL;
421 	}
422 
423 	if (skb->len < ETH_HLEN) {
424 		wil_err(wil, "Short frame, len = %d\n", skb->len);
425 		/* TODO: process it (i.e. BAR) */
426 		kfree_skb(skb);
427 		return NULL;
428 	}
429 
430 	/* L4 IDENT is on when HW calculated checksum, check status
431 	 * and in case of error drop the packet
432 	 * higher stack layers will handle retransmission (if required)
433 	 */
434 	if (d->dma.status & RX_DMA_STATUS_L4_IDENT) {
435 		/* L4 protocol identified, csum calculated */
436 		if ((d->dma.error & RX_DMA_ERROR_L4_ERR) == 0)
437 			skb->ip_summed = CHECKSUM_UNNECESSARY;
438 		/* If HW reports bad checksum, let IP stack re-check it
439 		 * For example, HW don't understand Microsoft IP stack that
440 		 * mis-calculates TCP checksum - if it should be 0x0,
441 		 * it writes 0xffff in violation of RFC 1624
442 		 */
443 	}
444 
445 	ds_bits = wil_rxdesc_ds_bits(d);
446 	if (ds_bits == 1) {
447 		/*
448 		 * HW bug - in ToDS mode, i.e. Rx on AP side,
449 		 * addresses get swapped
450 		 */
451 		wil_swap_ethaddr(skb->data);
452 	}
453 
454 	return skb;
455 }
456 
457 /**
458  * allocate and fill up to @count buffers in rx ring
459  * buffers posted at @swtail
460  */
461 static int wil_rx_refill(struct wil6210_priv *wil, int count)
462 {
463 	struct net_device *ndev = wil_to_ndev(wil);
464 	struct vring *v = &wil->vring_rx;
465 	u32 next_tail;
466 	int rc = 0;
467 	int headroom = ndev->type == ARPHRD_IEEE80211_RADIOTAP ?
468 			WIL6210_RTAP_SIZE : 0;
469 
470 	for (; next_tail = wil_vring_next_tail(v),
471 			(next_tail != v->swhead) && (count-- > 0);
472 			v->swtail = next_tail) {
473 		rc = wil_vring_alloc_skb(wil, v, v->swtail, headroom);
474 		if (rc) {
475 			wil_err(wil, "Error %d in wil_rx_refill[%d]\n",
476 				rc, v->swtail);
477 			break;
478 		}
479 	}
480 	iowrite32(v->swtail, wil->csr + HOSTADDR(v->hwtail));
481 
482 	return rc;
483 }
484 
485 /*
486  * Pass Rx packet to the netif. Update statistics.
487  * Called in softirq context (NAPI poll).
488  */
489 void wil_netif_rx_any(struct sk_buff *skb, struct net_device *ndev)
490 {
491 	gro_result_t rc;
492 	struct wil6210_priv *wil = ndev_to_wil(ndev);
493 	unsigned int len = skb->len;
494 	struct vring_rx_desc *d = wil_skb_rxdesc(skb);
495 	int cid = wil_rxdesc_cid(d);
496 	struct wil_net_stats *stats = &wil->sta[cid].stats;
497 
498 	skb_orphan(skb);
499 
500 	rc = napi_gro_receive(&wil->napi_rx, skb);
501 
502 	if (unlikely(rc == GRO_DROP)) {
503 		ndev->stats.rx_dropped++;
504 		stats->rx_dropped++;
505 		wil_dbg_txrx(wil, "Rx drop %d bytes\n", len);
506 	} else {
507 		ndev->stats.rx_packets++;
508 		stats->rx_packets++;
509 		ndev->stats.rx_bytes += len;
510 		stats->rx_bytes += len;
511 	}
512 }
513 
514 /**
515  * Proceed all completed skb's from Rx VRING
516  *
517  * Safe to call from NAPI poll, i.e. softirq with interrupts enabled
518  */
519 void wil_rx_handle(struct wil6210_priv *wil, int *quota)
520 {
521 	struct net_device *ndev = wil_to_ndev(wil);
522 	struct vring *v = &wil->vring_rx;
523 	struct sk_buff *skb;
524 
525 	if (!v->va) {
526 		wil_err(wil, "Rx IRQ while Rx not yet initialized\n");
527 		return;
528 	}
529 	wil_dbg_txrx(wil, "%s()\n", __func__);
530 	while ((*quota > 0) && (NULL != (skb = wil_vring_reap_rx(wil, v)))) {
531 		(*quota)--;
532 
533 		if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
534 			skb->dev = ndev;
535 			skb_reset_mac_header(skb);
536 			skb->ip_summed = CHECKSUM_UNNECESSARY;
537 			skb->pkt_type = PACKET_OTHERHOST;
538 			skb->protocol = htons(ETH_P_802_2);
539 			wil_netif_rx_any(skb, ndev);
540 		} else {
541 			struct ethhdr *eth = (void *)skb->data;
542 
543 			skb->protocol = eth_type_trans(skb, ndev);
544 
545 			if (is_unicast_ether_addr(eth->h_dest))
546 				wil_rx_reorder(wil, skb);
547 			else
548 				wil_netif_rx_any(skb, ndev);
549 		}
550 
551 	}
552 	wil_rx_refill(wil, v->size);
553 }
554 
555 int wil_rx_init(struct wil6210_priv *wil)
556 {
557 	struct vring *vring = &wil->vring_rx;
558 	int rc;
559 
560 	if (vring->va) {
561 		wil_err(wil, "Rx ring already allocated\n");
562 		return -EINVAL;
563 	}
564 
565 	vring->size = WIL6210_RX_RING_SIZE;
566 	rc = wil_vring_alloc(wil, vring);
567 	if (rc)
568 		return rc;
569 
570 	rc = wmi_rx_chain_add(wil, vring);
571 	if (rc)
572 		goto err_free;
573 
574 	rc = wil_rx_refill(wil, vring->size);
575 	if (rc)
576 		goto err_free;
577 
578 	return 0;
579  err_free:
580 	wil_vring_free(wil, vring, 0);
581 
582 	return rc;
583 }
584 
585 void wil_rx_fini(struct wil6210_priv *wil)
586 {
587 	struct vring *vring = &wil->vring_rx;
588 
589 	if (vring->va)
590 		wil_vring_free(wil, vring, 0);
591 }
592 
593 int wil_vring_init_tx(struct wil6210_priv *wil, int id, int size,
594 		      int cid, int tid)
595 {
596 	int rc;
597 	struct wmi_vring_cfg_cmd cmd = {
598 		.action = cpu_to_le32(WMI_VRING_CMD_ADD),
599 		.vring_cfg = {
600 			.tx_sw_ring = {
601 				.max_mpdu_size = cpu_to_le16(TX_BUF_LEN),
602 				.ring_size = cpu_to_le16(size),
603 			},
604 			.ringid = id,
605 			.cidxtid = mk_cidxtid(cid, tid),
606 			.encap_trans_type = WMI_VRING_ENC_TYPE_802_3,
607 			.mac_ctrl = 0,
608 			.to_resolution = 0,
609 			.agg_max_wsize = 16,
610 			.schd_params = {
611 				.priority = cpu_to_le16(0),
612 				.timeslot_us = cpu_to_le16(0xfff),
613 			},
614 		},
615 	};
616 	struct {
617 		struct wil6210_mbox_hdr_wmi wmi;
618 		struct wmi_vring_cfg_done_event cmd;
619 	} __packed reply;
620 	struct vring *vring = &wil->vring_tx[id];
621 	struct vring_tx_data *txdata = &wil->vring_tx_data[id];
622 
623 	if (vring->va) {
624 		wil_err(wil, "Tx ring [%d] already allocated\n", id);
625 		rc = -EINVAL;
626 		goto out;
627 	}
628 
629 	memset(txdata, 0, sizeof(*txdata));
630 	vring->size = size;
631 	rc = wil_vring_alloc(wil, vring);
632 	if (rc)
633 		goto out;
634 
635 	wil->vring2cid_tid[id][0] = cid;
636 	wil->vring2cid_tid[id][1] = tid;
637 
638 	cmd.vring_cfg.tx_sw_ring.ring_mem_base = cpu_to_le64(vring->pa);
639 
640 	rc = wmi_call(wil, WMI_VRING_CFG_CMDID, &cmd, sizeof(cmd),
641 		      WMI_VRING_CFG_DONE_EVENTID, &reply, sizeof(reply), 100);
642 	if (rc)
643 		goto out_free;
644 
645 	if (reply.cmd.status != WMI_FW_STATUS_SUCCESS) {
646 		wil_err(wil, "Tx config failed, status 0x%02x\n",
647 			reply.cmd.status);
648 		rc = -EINVAL;
649 		goto out_free;
650 	}
651 	vring->hwtail = le32_to_cpu(reply.cmd.tx_vring_tail_ptr);
652 
653 	txdata->enabled = 1;
654 
655 	return 0;
656  out_free:
657 	wil_vring_free(wil, vring, 1);
658  out:
659 
660 	return rc;
661 }
662 
663 void wil_vring_fini_tx(struct wil6210_priv *wil, int id)
664 {
665 	struct vring *vring = &wil->vring_tx[id];
666 
667 	WARN_ON(!mutex_is_locked(&wil->mutex));
668 
669 	if (!vring->va)
670 		return;
671 
672 	/* make sure NAPI won't touch this vring */
673 	wil->vring_tx_data[id].enabled = 0;
674 	if (test_bit(wil_status_napi_en, &wil->status))
675 		napi_synchronize(&wil->napi_tx);
676 
677 	wil_vring_free(wil, vring, 1);
678 }
679 
680 static struct vring *wil_find_tx_vring(struct wil6210_priv *wil,
681 				       struct sk_buff *skb)
682 {
683 	int i;
684 	struct ethhdr *eth = (void *)skb->data;
685 	int cid = wil_find_cid(wil, eth->h_dest);
686 
687 	if (cid < 0)
688 		return NULL;
689 
690 	if (!wil->sta[cid].data_port_open &&
691 	    (skb->protocol != cpu_to_be16(ETH_P_PAE)))
692 		return NULL;
693 
694 	/* TODO: fix for multiple TID */
695 	for (i = 0; i < ARRAY_SIZE(wil->vring2cid_tid); i++) {
696 		if (wil->vring2cid_tid[i][0] == cid) {
697 			struct vring *v = &wil->vring_tx[i];
698 			wil_dbg_txrx(wil, "%s(%pM) -> [%d]\n",
699 				     __func__, eth->h_dest, i);
700 			if (v->va) {
701 				return v;
702 			} else {
703 				wil_dbg_txrx(wil, "vring[%d] not valid\n", i);
704 				return NULL;
705 			}
706 		}
707 	}
708 
709 	return NULL;
710 }
711 
712 static void wil_set_da_for_vring(struct wil6210_priv *wil,
713 				 struct sk_buff *skb, int vring_index)
714 {
715 	struct ethhdr *eth = (void *)skb->data;
716 	int cid = wil->vring2cid_tid[vring_index][0];
717 	memcpy(eth->h_dest, wil->sta[cid].addr, ETH_ALEN);
718 }
719 
720 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
721 			struct sk_buff *skb);
722 /*
723  * Find 1-st vring and return it; set dest address for this vring in skb
724  * duplicate skb and send it to other active vrings
725  */
726 static struct vring *wil_tx_bcast(struct wil6210_priv *wil,
727 				       struct sk_buff *skb)
728 {
729 	struct vring *v, *v2;
730 	struct sk_buff *skb2;
731 	int i;
732 	u8 cid;
733 
734 	/* find 1-st vring eligible for data */
735 	for (i = 0; i < WIL6210_MAX_TX_RINGS; i++) {
736 		v = &wil->vring_tx[i];
737 		if (!v->va)
738 			continue;
739 
740 		cid = wil->vring2cid_tid[i][0];
741 		if (!wil->sta[cid].data_port_open)
742 			continue;
743 
744 		goto found;
745 	}
746 
747 	wil_err(wil, "Tx while no vrings active?\n");
748 
749 	return NULL;
750 
751 found:
752 	wil_dbg_txrx(wil, "BCAST -> ring %d\n", i);
753 	wil_set_da_for_vring(wil, skb, i);
754 
755 	/* find other active vrings and duplicate skb for each */
756 	for (i++; i < WIL6210_MAX_TX_RINGS; i++) {
757 		v2 = &wil->vring_tx[i];
758 		if (!v2->va)
759 			continue;
760 		cid = wil->vring2cid_tid[i][0];
761 		if (!wil->sta[cid].data_port_open)
762 			continue;
763 
764 		skb2 = skb_copy(skb, GFP_ATOMIC);
765 		if (skb2) {
766 			wil_dbg_txrx(wil, "BCAST DUP -> ring %d\n", i);
767 			wil_set_da_for_vring(wil, skb2, i);
768 			wil_tx_vring(wil, v2, skb2);
769 		} else {
770 			wil_err(wil, "skb_copy failed\n");
771 		}
772 	}
773 
774 	return v;
775 }
776 
777 static int wil_tx_desc_map(struct vring_tx_desc *d, dma_addr_t pa, u32 len,
778 			   int vring_index)
779 {
780 	wil_desc_addr_set(&d->dma.addr, pa);
781 	d->dma.ip_length = 0;
782 	/* 0..6: mac_length; 7:ip_version 0-IP6 1-IP4*/
783 	d->dma.b11 = 0/*14 | BIT(7)*/;
784 	d->dma.error = 0;
785 	d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
786 	d->dma.length = cpu_to_le16((u16)len);
787 	d->dma.d0 = (vring_index << DMA_CFG_DESC_TX_0_QID_POS);
788 	d->mac.d[0] = 0;
789 	d->mac.d[1] = 0;
790 	d->mac.d[2] = 0;
791 	d->mac.ucode_cmd = 0;
792 	/* use dst index 0 */
793 	d->mac.d[1] |= BIT(MAC_CFG_DESC_TX_1_DST_INDEX_EN_POS) |
794 		       (0 << MAC_CFG_DESC_TX_1_DST_INDEX_POS);
795 	/* translation type:  0 - bypass; 1 - 802.3; 2 - native wifi */
796 	d->mac.d[2] = BIT(MAC_CFG_DESC_TX_2_SNAP_HDR_INSERTION_EN_POS) |
797 		      (1 << MAC_CFG_DESC_TX_2_L2_TRANSLATION_TYPE_POS);
798 
799 	return 0;
800 }
801 
802 static inline
803 void wil_tx_desc_set_nr_frags(struct vring_tx_desc *d, int nr_frags)
804 {
805 	d->mac.d[2] |= ((nr_frags + 1) <<
806 		       MAC_CFG_DESC_TX_2_NUM_OF_DESCRIPTORS_POS);
807 }
808 
809 static int wil_tx_desc_offload_cksum_set(struct wil6210_priv *wil,
810 				struct vring_tx_desc *d,
811 				struct sk_buff *skb)
812 {
813 	int protocol;
814 
815 	if (skb->ip_summed != CHECKSUM_PARTIAL)
816 		return 0;
817 
818 	d->dma.b11 = ETH_HLEN; /* MAC header length */
819 
820 	switch (skb->protocol) {
821 	case cpu_to_be16(ETH_P_IP):
822 		protocol = ip_hdr(skb)->protocol;
823 		d->dma.b11 |= BIT(DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_POS);
824 		break;
825 	case cpu_to_be16(ETH_P_IPV6):
826 		protocol = ipv6_hdr(skb)->nexthdr;
827 		break;
828 	default:
829 		return -EINVAL;
830 	}
831 
832 	switch (protocol) {
833 	case IPPROTO_TCP:
834 		d->dma.d0 |= (2 << DMA_CFG_DESC_TX_0_L4_TYPE_POS);
835 		/* L4 header len: TCP header length */
836 		d->dma.d0 |=
837 		(tcp_hdrlen(skb) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
838 		break;
839 	case IPPROTO_UDP:
840 		/* L4 header len: UDP header length */
841 		d->dma.d0 |=
842 		(sizeof(struct udphdr) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
843 		break;
844 	default:
845 		return -EINVAL;
846 	}
847 
848 	d->dma.ip_length = skb_network_header_len(skb);
849 	/* Enable TCP/UDP checksum */
850 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_TCP_UDP_CHECKSUM_EN_POS);
851 	/* Calculate pseudo-header */
852 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_PSEUDO_HEADER_CALC_EN_POS);
853 
854 	return 0;
855 }
856 
857 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
858 			struct sk_buff *skb)
859 {
860 	struct device *dev = wil_to_dev(wil);
861 	struct vring_tx_desc dd, *d = &dd;
862 	volatile struct vring_tx_desc *_d;
863 	u32 swhead = vring->swhead;
864 	int avail = wil_vring_avail_tx(vring);
865 	int nr_frags = skb_shinfo(skb)->nr_frags;
866 	uint f = 0;
867 	int vring_index = vring - wil->vring_tx;
868 	uint i = swhead;
869 	dma_addr_t pa;
870 
871 	wil_dbg_txrx(wil, "%s()\n", __func__);
872 
873 	if (avail < 1 + nr_frags) {
874 		wil_err(wil, "Tx ring full. No space for %d fragments\n",
875 			1 + nr_frags);
876 		return -ENOMEM;
877 	}
878 	_d = &(vring->va[i].tx);
879 
880 	pa = dma_map_single(dev, skb->data,
881 			skb_headlen(skb), DMA_TO_DEVICE);
882 
883 	wil_dbg_txrx(wil, "Tx skb %d bytes %p -> %#08llx\n", skb_headlen(skb),
884 		     skb->data, (unsigned long long)pa);
885 	wil_hex_dump_txrx("Tx ", DUMP_PREFIX_OFFSET, 16, 1,
886 			  skb->data, skb_headlen(skb), false);
887 
888 	if (unlikely(dma_mapping_error(dev, pa)))
889 		return -EINVAL;
890 	vring->ctx[i].mapped_as = wil_mapped_as_single;
891 	/* 1-st segment */
892 	wil_tx_desc_map(d, pa, skb_headlen(skb), vring_index);
893 	/* Process TCP/UDP checksum offloading */
894 	if (wil_tx_desc_offload_cksum_set(wil, d, skb)) {
895 		wil_err(wil, "VRING #%d Failed to set cksum, drop packet\n",
896 			vring_index);
897 		goto dma_error;
898 	}
899 
900 	vring->ctx[i].nr_frags = nr_frags;
901 	wil_tx_desc_set_nr_frags(d, nr_frags);
902 	if (nr_frags)
903 		*_d = *d;
904 
905 	/* middle segments */
906 	for (; f < nr_frags; f++) {
907 		const struct skb_frag_struct *frag =
908 				&skb_shinfo(skb)->frags[f];
909 		int len = skb_frag_size(frag);
910 		i = (swhead + f + 1) % vring->size;
911 		_d = &(vring->va[i].tx);
912 		pa = skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag),
913 				DMA_TO_DEVICE);
914 		if (unlikely(dma_mapping_error(dev, pa)))
915 			goto dma_error;
916 		vring->ctx[i].mapped_as = wil_mapped_as_page;
917 		wil_tx_desc_map(d, pa, len, vring_index);
918 		/* no need to check return code -
919 		 * if it succeeded for 1-st descriptor,
920 		 * it will succeed here too
921 		 */
922 		wil_tx_desc_offload_cksum_set(wil, d, skb);
923 		*_d = *d;
924 	}
925 	/* for the last seg only */
926 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_EOP_POS);
927 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_MARK_WB_POS);
928 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_DMA_IT_POS);
929 	*_d = *d;
930 
931 	/* hold reference to skb
932 	 * to prevent skb release before accounting
933 	 * in case of immediate "tx done"
934 	 */
935 	vring->ctx[i].skb = skb_get(skb);
936 
937 	wil_hex_dump_txrx("Tx ", DUMP_PREFIX_NONE, 32, 4,
938 			  (const void *)d, sizeof(*d), false);
939 
940 	/* advance swhead */
941 	wil_vring_advance_head(vring, nr_frags + 1);
942 	wil_dbg_txrx(wil, "Tx swhead %d -> %d\n", swhead, vring->swhead);
943 	trace_wil6210_tx(vring_index, swhead, skb->len, nr_frags);
944 	iowrite32(vring->swhead, wil->csr + HOSTADDR(vring->hwtail));
945 
946 	return 0;
947  dma_error:
948 	/* unmap what we have mapped */
949 	nr_frags = f + 1; /* frags mapped + one for skb head */
950 	for (f = 0; f < nr_frags; f++) {
951 		struct wil_ctx *ctx;
952 
953 		i = (swhead + f) % vring->size;
954 		ctx = &vring->ctx[i];
955 		_d = &(vring->va[i].tx);
956 		*d = *_d;
957 		_d->dma.status = TX_DMA_STATUS_DU;
958 		wil_txdesc_unmap(dev, d, ctx);
959 
960 		if (ctx->skb)
961 			dev_kfree_skb_any(ctx->skb);
962 
963 		memset(ctx, 0, sizeof(*ctx));
964 	}
965 
966 	return -EINVAL;
967 }
968 
969 
970 netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
971 {
972 	struct wil6210_priv *wil = ndev_to_wil(ndev);
973 	struct ethhdr *eth = (void *)skb->data;
974 	struct vring *vring;
975 	static bool pr_once_fw;
976 	int rc;
977 
978 	wil_dbg_txrx(wil, "%s()\n", __func__);
979 	if (!test_bit(wil_status_fwready, &wil->status)) {
980 		if (!pr_once_fw) {
981 			wil_err(wil, "FW not ready\n");
982 			pr_once_fw = true;
983 		}
984 		goto drop;
985 	}
986 	if (!test_bit(wil_status_fwconnected, &wil->status)) {
987 		wil_err(wil, "FW not connected\n");
988 		goto drop;
989 	}
990 	if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
991 		wil_err(wil, "Xmit in monitor mode not supported\n");
992 		goto drop;
993 	}
994 	pr_once_fw = false;
995 
996 	/* find vring */
997 	if (is_unicast_ether_addr(eth->h_dest)) {
998 		vring = wil_find_tx_vring(wil, skb);
999 	} else {
1000 		vring = wil_tx_bcast(wil, skb);
1001 	}
1002 	if (!vring) {
1003 		wil_err(wil, "No Tx VRING found for %pM\n", eth->h_dest);
1004 		goto drop;
1005 	}
1006 	/* set up vring entry */
1007 	rc = wil_tx_vring(wil, vring, skb);
1008 
1009 	/* do we still have enough room in the vring? */
1010 	if (wil_vring_avail_tx(vring) < vring->size/8)
1011 		netif_tx_stop_all_queues(wil_to_ndev(wil));
1012 
1013 	switch (rc) {
1014 	case 0:
1015 		/* statistics will be updated on the tx_complete */
1016 		dev_kfree_skb_any(skb);
1017 		return NETDEV_TX_OK;
1018 	case -ENOMEM:
1019 		return NETDEV_TX_BUSY;
1020 	default:
1021 		break; /* goto drop; */
1022 	}
1023  drop:
1024 	ndev->stats.tx_dropped++;
1025 	dev_kfree_skb_any(skb);
1026 
1027 	return NET_XMIT_DROP;
1028 }
1029 
1030 /**
1031  * Clean up transmitted skb's from the Tx VRING
1032  *
1033  * Return number of descriptors cleared
1034  *
1035  * Safe to call from IRQ
1036  */
1037 int wil_tx_complete(struct wil6210_priv *wil, int ringid)
1038 {
1039 	struct net_device *ndev = wil_to_ndev(wil);
1040 	struct device *dev = wil_to_dev(wil);
1041 	struct vring *vring = &wil->vring_tx[ringid];
1042 	struct vring_tx_data *txdata = &wil->vring_tx_data[ringid];
1043 	int done = 0;
1044 	int cid = wil->vring2cid_tid[ringid][0];
1045 	struct wil_net_stats *stats = &wil->sta[cid].stats;
1046 	volatile struct vring_tx_desc *_d;
1047 
1048 	if (!vring->va) {
1049 		wil_err(wil, "Tx irq[%d]: vring not initialized\n", ringid);
1050 		return 0;
1051 	}
1052 
1053 	if (!txdata->enabled) {
1054 		wil_info(wil, "Tx irq[%d]: vring disabled\n", ringid);
1055 		return 0;
1056 	}
1057 
1058 	wil_dbg_txrx(wil, "%s(%d)\n", __func__, ringid);
1059 
1060 	while (!wil_vring_is_empty(vring)) {
1061 		int new_swtail;
1062 		struct wil_ctx *ctx = &vring->ctx[vring->swtail];
1063 		/**
1064 		 * For the fragmented skb, HW will set DU bit only for the
1065 		 * last fragment. look for it
1066 		 */
1067 		int lf = (vring->swtail + ctx->nr_frags) % vring->size;
1068 		/* TODO: check we are not past head */
1069 
1070 		_d = &vring->va[lf].tx;
1071 		if (!(_d->dma.status & TX_DMA_STATUS_DU))
1072 			break;
1073 
1074 		new_swtail = (lf + 1) % vring->size;
1075 		while (vring->swtail != new_swtail) {
1076 			struct vring_tx_desc dd, *d = &dd;
1077 			u16 dmalen;
1078 			struct wil_ctx *ctx = &vring->ctx[vring->swtail];
1079 			struct sk_buff *skb = ctx->skb;
1080 			_d = &vring->va[vring->swtail].tx;
1081 
1082 			*d = *_d;
1083 
1084 			dmalen = le16_to_cpu(d->dma.length);
1085 			trace_wil6210_tx_done(ringid, vring->swtail, dmalen,
1086 					      d->dma.error);
1087 			wil_dbg_txrx(wil,
1088 				     "Tx[%3d] : %d bytes, status 0x%02x err 0x%02x\n",
1089 				     vring->swtail, dmalen, d->dma.status,
1090 				     d->dma.error);
1091 			wil_hex_dump_txrx("TxC ", DUMP_PREFIX_NONE, 32, 4,
1092 					  (const void *)d, sizeof(*d), false);
1093 
1094 			wil_txdesc_unmap(dev, d, ctx);
1095 
1096 			if (skb) {
1097 				if (d->dma.error == 0) {
1098 					ndev->stats.tx_packets++;
1099 					stats->tx_packets++;
1100 					ndev->stats.tx_bytes += skb->len;
1101 					stats->tx_bytes += skb->len;
1102 				} else {
1103 					ndev->stats.tx_errors++;
1104 					stats->tx_errors++;
1105 				}
1106 
1107 				dev_kfree_skb_any(skb);
1108 			}
1109 			memset(ctx, 0, sizeof(*ctx));
1110 			/* There is no need to touch HW descriptor:
1111 			 * - ststus bit TX_DMA_STATUS_DU is set by design,
1112 			 *   so hardware will not try to process this desc.,
1113 			 * - rest of descriptor will be initialized on Tx.
1114 			 */
1115 			vring->swtail = wil_vring_next_tail(vring);
1116 			done++;
1117 		}
1118 	}
1119 	if (wil_vring_avail_tx(vring) > vring->size/4)
1120 		netif_tx_wake_all_queues(wil_to_ndev(wil));
1121 
1122 	return done;
1123 }
1124