xref: /linux/drivers/net/wireless/ath/wil6210/txrx.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
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 /**
68  * wil_vring_wmark_low - low watermark for available descriptor space
69  */
70 static inline int wil_vring_wmark_low(struct vring *vring)
71 {
72 	return vring->size/8;
73 }
74 
75 /**
76  * wil_vring_wmark_high - high watermark for available descriptor space
77  */
78 static inline int wil_vring_wmark_high(struct vring *vring)
79 {
80 	return vring->size/4;
81 }
82 
83 static int wil_vring_alloc(struct wil6210_priv *wil, struct vring *vring)
84 {
85 	struct device *dev = wil_to_dev(wil);
86 	size_t sz = vring->size * sizeof(vring->va[0]);
87 	uint i;
88 
89 	BUILD_BUG_ON(sizeof(vring->va[0]) != 32);
90 
91 	vring->swhead = 0;
92 	vring->swtail = 0;
93 	vring->ctx = kcalloc(vring->size, sizeof(vring->ctx[0]), GFP_KERNEL);
94 	if (!vring->ctx) {
95 		vring->va = NULL;
96 		return -ENOMEM;
97 	}
98 	/*
99 	 * vring->va should be aligned on its size rounded up to power of 2
100 	 * This is granted by the dma_alloc_coherent
101 	 */
102 	vring->va = dma_alloc_coherent(dev, sz, &vring->pa, GFP_KERNEL);
103 	if (!vring->va) {
104 		kfree(vring->ctx);
105 		vring->ctx = NULL;
106 		return -ENOMEM;
107 	}
108 	/* initially, all descriptors are SW owned
109 	 * For Tx and Rx, ownership bit is at the same location, thus
110 	 * we can use any
111 	 */
112 	for (i = 0; i < vring->size; i++) {
113 		volatile struct vring_tx_desc *_d = &(vring->va[i].tx);
114 		_d->dma.status = TX_DMA_STATUS_DU;
115 	}
116 
117 	wil_dbg_misc(wil, "vring[%d] 0x%p:%pad 0x%p\n", vring->size,
118 		     vring->va, &vring->pa, vring->ctx);
119 
120 	return 0;
121 }
122 
123 static void wil_txdesc_unmap(struct device *dev, struct vring_tx_desc *d,
124 			     struct wil_ctx *ctx)
125 {
126 	dma_addr_t pa = wil_desc_addr(&d->dma.addr);
127 	u16 dmalen = le16_to_cpu(d->dma.length);
128 	switch (ctx->mapped_as) {
129 	case wil_mapped_as_single:
130 		dma_unmap_single(dev, pa, dmalen, DMA_TO_DEVICE);
131 		break;
132 	case wil_mapped_as_page:
133 		dma_unmap_page(dev, pa, dmalen, DMA_TO_DEVICE);
134 		break;
135 	default:
136 		break;
137 	}
138 }
139 
140 static void wil_vring_free(struct wil6210_priv *wil, struct vring *vring,
141 			   int tx)
142 {
143 	struct device *dev = wil_to_dev(wil);
144 	size_t sz = vring->size * sizeof(vring->va[0]);
145 
146 	while (!wil_vring_is_empty(vring)) {
147 		dma_addr_t pa;
148 		u16 dmalen;
149 		struct wil_ctx *ctx;
150 
151 		if (tx) {
152 			struct vring_tx_desc dd, *d = &dd;
153 			volatile struct vring_tx_desc *_d =
154 					&vring->va[vring->swtail].tx;
155 
156 			ctx = &vring->ctx[vring->swtail];
157 			*d = *_d;
158 			wil_txdesc_unmap(dev, d, ctx);
159 			if (ctx->skb)
160 				dev_kfree_skb_any(ctx->skb);
161 			vring->swtail = wil_vring_next_tail(vring);
162 		} else { /* rx */
163 			struct vring_rx_desc dd, *d = &dd;
164 			volatile struct vring_rx_desc *_d =
165 					&vring->va[vring->swhead].rx;
166 
167 			ctx = &vring->ctx[vring->swhead];
168 			*d = *_d;
169 			pa = wil_desc_addr(&d->dma.addr);
170 			dmalen = le16_to_cpu(d->dma.length);
171 			dma_unmap_single(dev, pa, dmalen, DMA_FROM_DEVICE);
172 			kfree_skb(ctx->skb);
173 			wil_vring_advance_head(vring, 1);
174 		}
175 	}
176 	dma_free_coherent(dev, sz, (void *)vring->va, vring->pa);
177 	kfree(vring->ctx);
178 	vring->pa = 0;
179 	vring->va = NULL;
180 	vring->ctx = NULL;
181 }
182 
183 /**
184  * Allocate one skb for Rx VRING
185  *
186  * Safe to call from IRQ
187  */
188 static int wil_vring_alloc_skb(struct wil6210_priv *wil, struct vring *vring,
189 			       u32 i, int headroom)
190 {
191 	struct device *dev = wil_to_dev(wil);
192 	unsigned int sz = RX_BUF_LEN;
193 	struct vring_rx_desc dd, *d = &dd;
194 	volatile struct vring_rx_desc *_d = &(vring->va[i].rx);
195 	dma_addr_t pa;
196 
197 	/* TODO align */
198 	struct sk_buff *skb = dev_alloc_skb(sz + headroom);
199 	if (unlikely(!skb))
200 		return -ENOMEM;
201 
202 	skb_reserve(skb, headroom);
203 	skb_put(skb, sz);
204 
205 	pa = dma_map_single(dev, skb->data, skb->len, DMA_FROM_DEVICE);
206 	if (unlikely(dma_mapping_error(dev, pa))) {
207 		kfree_skb(skb);
208 		return -ENOMEM;
209 	}
210 
211 	d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
212 	wil_desc_addr_set(&d->dma.addr, pa);
213 	/* ip_length don't care */
214 	/* b11 don't care */
215 	/* error don't care */
216 	d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
217 	d->dma.length = cpu_to_le16(sz);
218 	*_d = *d;
219 	vring->ctx[i].skb = skb;
220 
221 	return 0;
222 }
223 
224 /**
225  * Adds radiotap header
226  *
227  * Any error indicated as "Bad FCS"
228  *
229  * Vendor data for 04:ce:14-1 (Wilocity-1) consists of:
230  *  - Rx descriptor: 32 bytes
231  *  - Phy info
232  */
233 static void wil_rx_add_radiotap_header(struct wil6210_priv *wil,
234 				       struct sk_buff *skb)
235 {
236 	struct wireless_dev *wdev = wil->wdev;
237 	struct wil6210_rtap {
238 		struct ieee80211_radiotap_header rthdr;
239 		/* fields should be in the order of bits in rthdr.it_present */
240 		/* flags */
241 		u8 flags;
242 		/* channel */
243 		__le16 chnl_freq __aligned(2);
244 		__le16 chnl_flags;
245 		/* MCS */
246 		u8 mcs_present;
247 		u8 mcs_flags;
248 		u8 mcs_index;
249 	} __packed;
250 	struct wil6210_rtap_vendor {
251 		struct wil6210_rtap rtap;
252 		/* vendor */
253 		u8 vendor_oui[3] __aligned(2);
254 		u8 vendor_ns;
255 		__le16 vendor_skip;
256 		u8 vendor_data[0];
257 	} __packed;
258 	struct vring_rx_desc *d = wil_skb_rxdesc(skb);
259 	struct wil6210_rtap_vendor *rtap_vendor;
260 	int rtap_len = sizeof(struct wil6210_rtap);
261 	int phy_length = 0; /* phy info header size, bytes */
262 	static char phy_data[128];
263 	struct ieee80211_channel *ch = wdev->preset_chandef.chan;
264 
265 	if (rtap_include_phy_info) {
266 		rtap_len = sizeof(*rtap_vendor) + sizeof(*d);
267 		/* calculate additional length */
268 		if (d->dma.status & RX_DMA_STATUS_PHY_INFO) {
269 			/**
270 			 * PHY info starts from 8-byte boundary
271 			 * there are 8-byte lines, last line may be partially
272 			 * written (HW bug), thus FW configures for last line
273 			 * to be excessive. Driver skips this last line.
274 			 */
275 			int len = min_t(int, 8 + sizeof(phy_data),
276 					wil_rxdesc_phy_length(d));
277 			if (len > 8) {
278 				void *p = skb_tail_pointer(skb);
279 				void *pa = PTR_ALIGN(p, 8);
280 				if (skb_tailroom(skb) >= len + (pa - p)) {
281 					phy_length = len - 8;
282 					memcpy(phy_data, pa, phy_length);
283 				}
284 			}
285 		}
286 		rtap_len += phy_length;
287 	}
288 
289 	if (skb_headroom(skb) < rtap_len &&
290 	    pskb_expand_head(skb, rtap_len, 0, GFP_ATOMIC)) {
291 		wil_err(wil, "Unable to expand headrom to %d\n", rtap_len);
292 		return;
293 	}
294 
295 	rtap_vendor = (void *)skb_push(skb, rtap_len);
296 	memset(rtap_vendor, 0, rtap_len);
297 
298 	rtap_vendor->rtap.rthdr.it_version = PKTHDR_RADIOTAP_VERSION;
299 	rtap_vendor->rtap.rthdr.it_len = cpu_to_le16(rtap_len);
300 	rtap_vendor->rtap.rthdr.it_present = cpu_to_le32(
301 			(1 << IEEE80211_RADIOTAP_FLAGS) |
302 			(1 << IEEE80211_RADIOTAP_CHANNEL) |
303 			(1 << IEEE80211_RADIOTAP_MCS));
304 	if (d->dma.status & RX_DMA_STATUS_ERROR)
305 		rtap_vendor->rtap.flags |= IEEE80211_RADIOTAP_F_BADFCS;
306 
307 	rtap_vendor->rtap.chnl_freq = cpu_to_le16(ch ? ch->center_freq : 58320);
308 	rtap_vendor->rtap.chnl_flags = cpu_to_le16(0);
309 
310 	rtap_vendor->rtap.mcs_present = IEEE80211_RADIOTAP_MCS_HAVE_MCS;
311 	rtap_vendor->rtap.mcs_flags = 0;
312 	rtap_vendor->rtap.mcs_index = wil_rxdesc_mcs(d);
313 
314 	if (rtap_include_phy_info) {
315 		rtap_vendor->rtap.rthdr.it_present |= cpu_to_le32(1 <<
316 				IEEE80211_RADIOTAP_VENDOR_NAMESPACE);
317 		/* OUI for Wilocity 04:ce:14 */
318 		rtap_vendor->vendor_oui[0] = 0x04;
319 		rtap_vendor->vendor_oui[1] = 0xce;
320 		rtap_vendor->vendor_oui[2] = 0x14;
321 		rtap_vendor->vendor_ns = 1;
322 		/* Rx descriptor + PHY data  */
323 		rtap_vendor->vendor_skip = cpu_to_le16(sizeof(*d) +
324 						       phy_length);
325 		memcpy(rtap_vendor->vendor_data, (void *)d, sizeof(*d));
326 		memcpy(rtap_vendor->vendor_data + sizeof(*d), phy_data,
327 		       phy_length);
328 	}
329 }
330 
331 /*
332  * Fast swap in place between 2 registers
333  */
334 static void wil_swap_u16(u16 *a, u16 *b)
335 {
336 	*a ^= *b;
337 	*b ^= *a;
338 	*a ^= *b;
339 }
340 
341 static void wil_swap_ethaddr(void *data)
342 {
343 	struct ethhdr *eth = data;
344 	u16 *s = (u16 *)eth->h_source;
345 	u16 *d = (u16 *)eth->h_dest;
346 
347 	wil_swap_u16(s++, d++);
348 	wil_swap_u16(s++, d++);
349 	wil_swap_u16(s, d);
350 }
351 
352 /**
353  * reap 1 frame from @swhead
354  *
355  * Rx descriptor copied to skb->cb
356  *
357  * Safe to call from IRQ
358  */
359 static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
360 					 struct vring *vring)
361 {
362 	struct device *dev = wil_to_dev(wil);
363 	struct net_device *ndev = wil_to_ndev(wil);
364 	volatile struct vring_rx_desc *_d;
365 	struct vring_rx_desc *d;
366 	struct sk_buff *skb;
367 	dma_addr_t pa;
368 	unsigned int sz = RX_BUF_LEN;
369 	u16 dmalen;
370 	u8 ftype;
371 	u8 ds_bits;
372 	int cid;
373 	struct wil_net_stats *stats;
374 
375 
376 	BUILD_BUG_ON(sizeof(struct vring_rx_desc) > sizeof(skb->cb));
377 
378 	if (wil_vring_is_empty(vring))
379 		return NULL;
380 
381 	_d = &(vring->va[vring->swhead].rx);
382 	if (!(_d->dma.status & RX_DMA_STATUS_DU)) {
383 		/* it is not error, we just reached end of Rx done area */
384 		return NULL;
385 	}
386 
387 	skb = vring->ctx[vring->swhead].skb;
388 	d = wil_skb_rxdesc(skb);
389 	*d = *_d;
390 	pa = wil_desc_addr(&d->dma.addr);
391 	vring->ctx[vring->swhead].skb = NULL;
392 	wil_vring_advance_head(vring, 1);
393 
394 	dma_unmap_single(dev, pa, sz, DMA_FROM_DEVICE);
395 	dmalen = le16_to_cpu(d->dma.length);
396 
397 	trace_wil6210_rx(vring->swhead, d);
398 	wil_dbg_txrx(wil, "Rx[%3d] : %d bytes\n", vring->swhead, dmalen);
399 	wil_hex_dump_txrx("Rx ", DUMP_PREFIX_NONE, 32, 4,
400 			  (const void *)d, sizeof(*d), false);
401 
402 	if (dmalen > sz) {
403 		wil_err(wil, "Rx size too large: %d bytes!\n", dmalen);
404 		kfree_skb(skb);
405 		return NULL;
406 	}
407 	skb_trim(skb, dmalen);
408 
409 	prefetch(skb->data);
410 
411 	wil_hex_dump_txrx("Rx ", DUMP_PREFIX_OFFSET, 16, 1,
412 			  skb->data, skb_headlen(skb), false);
413 
414 	cid = wil_rxdesc_cid(d);
415 	stats = &wil->sta[cid].stats;
416 	stats->last_mcs_rx = wil_rxdesc_mcs(d);
417 	wil->stats.last_mcs_rx = stats->last_mcs_rx;
418 
419 	/* use radiotap header only if required */
420 	if (ndev->type == ARPHRD_IEEE80211_RADIOTAP)
421 		wil_rx_add_radiotap_header(wil, skb);
422 
423 	/* no extra checks if in sniffer mode */
424 	if (ndev->type != ARPHRD_ETHER)
425 		return skb;
426 	/*
427 	 * Non-data frames may be delivered through Rx DMA channel (ex: BAR)
428 	 * Driver should recognize it by frame type, that is found
429 	 * in Rx descriptor. If type is not data, it is 802.11 frame as is
430 	 */
431 	ftype = wil_rxdesc_ftype(d) << 2;
432 	if (ftype != IEEE80211_FTYPE_DATA) {
433 		wil_dbg_txrx(wil, "Non-data frame ftype 0x%08x\n", ftype);
434 		/* TODO: process it */
435 		kfree_skb(skb);
436 		return NULL;
437 	}
438 
439 	if (skb->len < ETH_HLEN) {
440 		wil_err(wil, "Short frame, len = %d\n", skb->len);
441 		/* TODO: process it (i.e. BAR) */
442 		kfree_skb(skb);
443 		return NULL;
444 	}
445 
446 	/* L4 IDENT is on when HW calculated checksum, check status
447 	 * and in case of error drop the packet
448 	 * higher stack layers will handle retransmission (if required)
449 	 */
450 	if (d->dma.status & RX_DMA_STATUS_L4_IDENT) {
451 		/* L4 protocol identified, csum calculated */
452 		if ((d->dma.error & RX_DMA_ERROR_L4_ERR) == 0)
453 			skb->ip_summed = CHECKSUM_UNNECESSARY;
454 		/* If HW reports bad checksum, let IP stack re-check it
455 		 * For example, HW don't understand Microsoft IP stack that
456 		 * mis-calculates TCP checksum - if it should be 0x0,
457 		 * it writes 0xffff in violation of RFC 1624
458 		 */
459 	}
460 
461 	ds_bits = wil_rxdesc_ds_bits(d);
462 	if (ds_bits == 1) {
463 		/*
464 		 * HW bug - in ToDS mode, i.e. Rx on AP side,
465 		 * addresses get swapped
466 		 */
467 		wil_swap_ethaddr(skb->data);
468 	}
469 
470 	return skb;
471 }
472 
473 /**
474  * allocate and fill up to @count buffers in rx ring
475  * buffers posted at @swtail
476  */
477 static int wil_rx_refill(struct wil6210_priv *wil, int count)
478 {
479 	struct net_device *ndev = wil_to_ndev(wil);
480 	struct vring *v = &wil->vring_rx;
481 	u32 next_tail;
482 	int rc = 0;
483 	int headroom = ndev->type == ARPHRD_IEEE80211_RADIOTAP ?
484 			WIL6210_RTAP_SIZE : 0;
485 
486 	for (; next_tail = wil_vring_next_tail(v),
487 			(next_tail != v->swhead) && (count-- > 0);
488 			v->swtail = next_tail) {
489 		rc = wil_vring_alloc_skb(wil, v, v->swtail, headroom);
490 		if (rc) {
491 			wil_err(wil, "Error %d in wil_rx_refill[%d]\n",
492 				rc, v->swtail);
493 			break;
494 		}
495 	}
496 	iowrite32(v->swtail, wil->csr + HOSTADDR(v->hwtail));
497 
498 	return rc;
499 }
500 
501 /*
502  * Pass Rx packet to the netif. Update statistics.
503  * Called in softirq context (NAPI poll).
504  */
505 void wil_netif_rx_any(struct sk_buff *skb, struct net_device *ndev)
506 {
507 	gro_result_t rc;
508 	struct wil6210_priv *wil = ndev_to_wil(ndev);
509 	unsigned int len = skb->len;
510 	struct vring_rx_desc *d = wil_skb_rxdesc(skb);
511 	int cid = wil_rxdesc_cid(d);
512 	struct wil_net_stats *stats = &wil->sta[cid].stats;
513 
514 	skb_orphan(skb);
515 
516 	rc = napi_gro_receive(&wil->napi_rx, skb);
517 
518 	if (unlikely(rc == GRO_DROP)) {
519 		ndev->stats.rx_dropped++;
520 		stats->rx_dropped++;
521 		wil_dbg_txrx(wil, "Rx drop %d bytes\n", len);
522 	} else {
523 		ndev->stats.rx_packets++;
524 		stats->rx_packets++;
525 		ndev->stats.rx_bytes += len;
526 		stats->rx_bytes += len;
527 	}
528 	{
529 		static const char * const gro_res_str[] = {
530 			[GRO_MERGED]		= "GRO_MERGED",
531 			[GRO_MERGED_FREE]	= "GRO_MERGED_FREE",
532 			[GRO_HELD]		= "GRO_HELD",
533 			[GRO_NORMAL]		= "GRO_NORMAL",
534 			[GRO_DROP]		= "GRO_DROP",
535 		};
536 		wil_dbg_txrx(wil, "Rx complete %d bytes => %s,\n",
537 			     len, gro_res_str[rc]);
538 	}
539 }
540 
541 /**
542  * Proceed all completed skb's from Rx VRING
543  *
544  * Safe to call from NAPI poll, i.e. softirq with interrupts enabled
545  */
546 void wil_rx_handle(struct wil6210_priv *wil, int *quota)
547 {
548 	struct net_device *ndev = wil_to_ndev(wil);
549 	struct vring *v = &wil->vring_rx;
550 	struct sk_buff *skb;
551 
552 	if (!v->va) {
553 		wil_err(wil, "Rx IRQ while Rx not yet initialized\n");
554 		return;
555 	}
556 	wil_dbg_txrx(wil, "%s()\n", __func__);
557 	while ((*quota > 0) && (NULL != (skb = wil_vring_reap_rx(wil, v)))) {
558 		(*quota)--;
559 
560 		if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
561 			skb->dev = ndev;
562 			skb_reset_mac_header(skb);
563 			skb->ip_summed = CHECKSUM_UNNECESSARY;
564 			skb->pkt_type = PACKET_OTHERHOST;
565 			skb->protocol = htons(ETH_P_802_2);
566 			wil_netif_rx_any(skb, ndev);
567 		} else {
568 			struct ethhdr *eth = (void *)skb->data;
569 
570 			skb->protocol = eth_type_trans(skb, ndev);
571 
572 			if (is_unicast_ether_addr(eth->h_dest))
573 				wil_rx_reorder(wil, skb);
574 			else
575 				wil_netif_rx_any(skb, ndev);
576 		}
577 
578 	}
579 	wil_rx_refill(wil, v->size);
580 }
581 
582 int wil_rx_init(struct wil6210_priv *wil)
583 {
584 	struct vring *vring = &wil->vring_rx;
585 	int rc;
586 
587 	if (vring->va) {
588 		wil_err(wil, "Rx ring already allocated\n");
589 		return -EINVAL;
590 	}
591 
592 	vring->size = WIL6210_RX_RING_SIZE;
593 	rc = wil_vring_alloc(wil, vring);
594 	if (rc)
595 		return rc;
596 
597 	rc = wmi_rx_chain_add(wil, vring);
598 	if (rc)
599 		goto err_free;
600 
601 	rc = wil_rx_refill(wil, vring->size);
602 	if (rc)
603 		goto err_free;
604 
605 	return 0;
606  err_free:
607 	wil_vring_free(wil, vring, 0);
608 
609 	return rc;
610 }
611 
612 void wil_rx_fini(struct wil6210_priv *wil)
613 {
614 	struct vring *vring = &wil->vring_rx;
615 
616 	if (vring->va)
617 		wil_vring_free(wil, vring, 0);
618 }
619 
620 int wil_vring_init_tx(struct wil6210_priv *wil, int id, int size,
621 		      int cid, int tid)
622 {
623 	int rc;
624 	struct wmi_vring_cfg_cmd cmd = {
625 		.action = cpu_to_le32(WMI_VRING_CMD_ADD),
626 		.vring_cfg = {
627 			.tx_sw_ring = {
628 				.max_mpdu_size = cpu_to_le16(TX_BUF_LEN),
629 				.ring_size = cpu_to_le16(size),
630 			},
631 			.ringid = id,
632 			.cidxtid = mk_cidxtid(cid, tid),
633 			.encap_trans_type = WMI_VRING_ENC_TYPE_802_3,
634 			.mac_ctrl = 0,
635 			.to_resolution = 0,
636 			.agg_max_wsize = 16,
637 			.schd_params = {
638 				.priority = cpu_to_le16(0),
639 				.timeslot_us = cpu_to_le16(0xfff),
640 			},
641 		},
642 	};
643 	struct {
644 		struct wil6210_mbox_hdr_wmi wmi;
645 		struct wmi_vring_cfg_done_event cmd;
646 	} __packed reply;
647 	struct vring *vring = &wil->vring_tx[id];
648 	struct vring_tx_data *txdata = &wil->vring_tx_data[id];
649 
650 	if (vring->va) {
651 		wil_err(wil, "Tx ring [%d] already allocated\n", id);
652 		rc = -EINVAL;
653 		goto out;
654 	}
655 
656 	memset(txdata, 0, sizeof(*txdata));
657 	vring->size = size;
658 	rc = wil_vring_alloc(wil, vring);
659 	if (rc)
660 		goto out;
661 
662 	wil->vring2cid_tid[id][0] = cid;
663 	wil->vring2cid_tid[id][1] = tid;
664 
665 	cmd.vring_cfg.tx_sw_ring.ring_mem_base = cpu_to_le64(vring->pa);
666 
667 	rc = wmi_call(wil, WMI_VRING_CFG_CMDID, &cmd, sizeof(cmd),
668 		      WMI_VRING_CFG_DONE_EVENTID, &reply, sizeof(reply), 100);
669 	if (rc)
670 		goto out_free;
671 
672 	if (reply.cmd.status != WMI_FW_STATUS_SUCCESS) {
673 		wil_err(wil, "Tx config failed, status 0x%02x\n",
674 			reply.cmd.status);
675 		rc = -EINVAL;
676 		goto out_free;
677 	}
678 	vring->hwtail = le32_to_cpu(reply.cmd.tx_vring_tail_ptr);
679 
680 	txdata->enabled = 1;
681 
682 	return 0;
683  out_free:
684 	wil_vring_free(wil, vring, 1);
685  out:
686 
687 	return rc;
688 }
689 
690 void wil_vring_fini_tx(struct wil6210_priv *wil, int id)
691 {
692 	struct vring *vring = &wil->vring_tx[id];
693 
694 	WARN_ON(!mutex_is_locked(&wil->mutex));
695 
696 	if (!vring->va)
697 		return;
698 
699 	/* make sure NAPI won't touch this vring */
700 	wil->vring_tx_data[id].enabled = 0;
701 	if (test_bit(wil_status_napi_en, &wil->status))
702 		napi_synchronize(&wil->napi_tx);
703 
704 	wil_vring_free(wil, vring, 1);
705 }
706 
707 static struct vring *wil_find_tx_vring(struct wil6210_priv *wil,
708 				       struct sk_buff *skb)
709 {
710 	int i;
711 	struct ethhdr *eth = (void *)skb->data;
712 	int cid = wil_find_cid(wil, eth->h_dest);
713 
714 	if (cid < 0)
715 		return NULL;
716 
717 	if (!wil->sta[cid].data_port_open &&
718 	    (skb->protocol != cpu_to_be16(ETH_P_PAE)))
719 		return NULL;
720 
721 	/* TODO: fix for multiple TID */
722 	for (i = 0; i < ARRAY_SIZE(wil->vring2cid_tid); i++) {
723 		if (wil->vring2cid_tid[i][0] == cid) {
724 			struct vring *v = &wil->vring_tx[i];
725 			wil_dbg_txrx(wil, "%s(%pM) -> [%d]\n",
726 				     __func__, eth->h_dest, i);
727 			if (v->va) {
728 				return v;
729 			} else {
730 				wil_dbg_txrx(wil, "vring[%d] not valid\n", i);
731 				return NULL;
732 			}
733 		}
734 	}
735 
736 	return NULL;
737 }
738 
739 static void wil_set_da_for_vring(struct wil6210_priv *wil,
740 				 struct sk_buff *skb, int vring_index)
741 {
742 	struct ethhdr *eth = (void *)skb->data;
743 	int cid = wil->vring2cid_tid[vring_index][0];
744 	memcpy(eth->h_dest, wil->sta[cid].addr, ETH_ALEN);
745 }
746 
747 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
748 			struct sk_buff *skb);
749 /*
750  * Find 1-st vring and return it; set dest address for this vring in skb
751  * duplicate skb and send it to other active vrings
752  */
753 static struct vring *wil_tx_bcast(struct wil6210_priv *wil,
754 				       struct sk_buff *skb)
755 {
756 	struct vring *v, *v2;
757 	struct sk_buff *skb2;
758 	int i;
759 	u8 cid;
760 
761 	/* find 1-st vring eligible for data */
762 	for (i = 0; i < WIL6210_MAX_TX_RINGS; i++) {
763 		v = &wil->vring_tx[i];
764 		if (!v->va)
765 			continue;
766 
767 		cid = wil->vring2cid_tid[i][0];
768 		if (!wil->sta[cid].data_port_open)
769 			continue;
770 
771 		goto found;
772 	}
773 
774 	wil_dbg_txrx(wil, "Tx while no vrings active?\n");
775 
776 	return NULL;
777 
778 found:
779 	wil_dbg_txrx(wil, "BCAST -> ring %d\n", i);
780 	wil_set_da_for_vring(wil, skb, i);
781 
782 	/* find other active vrings and duplicate skb for each */
783 	for (i++; i < WIL6210_MAX_TX_RINGS; i++) {
784 		v2 = &wil->vring_tx[i];
785 		if (!v2->va)
786 			continue;
787 		cid = wil->vring2cid_tid[i][0];
788 		if (!wil->sta[cid].data_port_open)
789 			continue;
790 
791 		skb2 = skb_copy(skb, GFP_ATOMIC);
792 		if (skb2) {
793 			wil_dbg_txrx(wil, "BCAST DUP -> ring %d\n", i);
794 			wil_set_da_for_vring(wil, skb2, i);
795 			wil_tx_vring(wil, v2, skb2);
796 		} else {
797 			wil_err(wil, "skb_copy failed\n");
798 		}
799 	}
800 
801 	return v;
802 }
803 
804 static int wil_tx_desc_map(struct vring_tx_desc *d, dma_addr_t pa, u32 len,
805 			   int vring_index)
806 {
807 	wil_desc_addr_set(&d->dma.addr, pa);
808 	d->dma.ip_length = 0;
809 	/* 0..6: mac_length; 7:ip_version 0-IP6 1-IP4*/
810 	d->dma.b11 = 0/*14 | BIT(7)*/;
811 	d->dma.error = 0;
812 	d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
813 	d->dma.length = cpu_to_le16((u16)len);
814 	d->dma.d0 = (vring_index << DMA_CFG_DESC_TX_0_QID_POS);
815 	d->mac.d[0] = 0;
816 	d->mac.d[1] = 0;
817 	d->mac.d[2] = 0;
818 	d->mac.ucode_cmd = 0;
819 	/* use dst index 0 */
820 	d->mac.d[1] |= BIT(MAC_CFG_DESC_TX_1_DST_INDEX_EN_POS) |
821 		       (0 << MAC_CFG_DESC_TX_1_DST_INDEX_POS);
822 	/* translation type:  0 - bypass; 1 - 802.3; 2 - native wifi */
823 	d->mac.d[2] = BIT(MAC_CFG_DESC_TX_2_SNAP_HDR_INSERTION_EN_POS) |
824 		      (1 << MAC_CFG_DESC_TX_2_L2_TRANSLATION_TYPE_POS);
825 
826 	return 0;
827 }
828 
829 static inline
830 void wil_tx_desc_set_nr_frags(struct vring_tx_desc *d, int nr_frags)
831 {
832 	d->mac.d[2] |= ((nr_frags + 1) <<
833 		       MAC_CFG_DESC_TX_2_NUM_OF_DESCRIPTORS_POS);
834 }
835 
836 static int wil_tx_desc_offload_cksum_set(struct wil6210_priv *wil,
837 				struct vring_tx_desc *d,
838 				struct sk_buff *skb)
839 {
840 	int protocol;
841 
842 	if (skb->ip_summed != CHECKSUM_PARTIAL)
843 		return 0;
844 
845 	d->dma.b11 = ETH_HLEN; /* MAC header length */
846 
847 	switch (skb->protocol) {
848 	case cpu_to_be16(ETH_P_IP):
849 		protocol = ip_hdr(skb)->protocol;
850 		d->dma.b11 |= BIT(DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_POS);
851 		break;
852 	case cpu_to_be16(ETH_P_IPV6):
853 		protocol = ipv6_hdr(skb)->nexthdr;
854 		break;
855 	default:
856 		return -EINVAL;
857 	}
858 
859 	switch (protocol) {
860 	case IPPROTO_TCP:
861 		d->dma.d0 |= (2 << DMA_CFG_DESC_TX_0_L4_TYPE_POS);
862 		/* L4 header len: TCP header length */
863 		d->dma.d0 |=
864 		(tcp_hdrlen(skb) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
865 		break;
866 	case IPPROTO_UDP:
867 		/* L4 header len: UDP header length */
868 		d->dma.d0 |=
869 		(sizeof(struct udphdr) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
870 		break;
871 	default:
872 		return -EINVAL;
873 	}
874 
875 	d->dma.ip_length = skb_network_header_len(skb);
876 	/* Enable TCP/UDP checksum */
877 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_TCP_UDP_CHECKSUM_EN_POS);
878 	/* Calculate pseudo-header */
879 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_PSEUDO_HEADER_CALC_EN_POS);
880 
881 	return 0;
882 }
883 
884 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
885 			struct sk_buff *skb)
886 {
887 	struct device *dev = wil_to_dev(wil);
888 	struct vring_tx_desc dd, *d = &dd;
889 	volatile struct vring_tx_desc *_d;
890 	u32 swhead = vring->swhead;
891 	int avail = wil_vring_avail_tx(vring);
892 	int nr_frags = skb_shinfo(skb)->nr_frags;
893 	uint f = 0;
894 	int vring_index = vring - wil->vring_tx;
895 	struct vring_tx_data *txdata = &wil->vring_tx_data[vring_index];
896 	uint i = swhead;
897 	dma_addr_t pa;
898 
899 	wil_dbg_txrx(wil, "%s()\n", __func__);
900 
901 	if (avail < 1 + nr_frags) {
902 		wil_err(wil, "Tx ring full. No space for %d fragments\n",
903 			1 + nr_frags);
904 		return -ENOMEM;
905 	}
906 	_d = &(vring->va[i].tx);
907 
908 	pa = dma_map_single(dev, skb->data,
909 			skb_headlen(skb), DMA_TO_DEVICE);
910 
911 	wil_dbg_txrx(wil, "Tx skb %d bytes 0x%p -> %pad\n", skb_headlen(skb),
912 		     skb->data, &pa);
913 	wil_hex_dump_txrx("Tx ", DUMP_PREFIX_OFFSET, 16, 1,
914 			  skb->data, skb_headlen(skb), false);
915 
916 	if (unlikely(dma_mapping_error(dev, pa)))
917 		return -EINVAL;
918 	vring->ctx[i].mapped_as = wil_mapped_as_single;
919 	/* 1-st segment */
920 	wil_tx_desc_map(d, pa, skb_headlen(skb), vring_index);
921 	/* Process TCP/UDP checksum offloading */
922 	if (wil_tx_desc_offload_cksum_set(wil, d, skb)) {
923 		wil_err(wil, "VRING #%d Failed to set cksum, drop packet\n",
924 			vring_index);
925 		goto dma_error;
926 	}
927 
928 	vring->ctx[i].nr_frags = nr_frags;
929 	wil_tx_desc_set_nr_frags(d, nr_frags);
930 	if (nr_frags)
931 		*_d = *d;
932 
933 	/* middle segments */
934 	for (; f < nr_frags; f++) {
935 		const struct skb_frag_struct *frag =
936 				&skb_shinfo(skb)->frags[f];
937 		int len = skb_frag_size(frag);
938 		i = (swhead + f + 1) % vring->size;
939 		_d = &(vring->va[i].tx);
940 		pa = skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag),
941 				DMA_TO_DEVICE);
942 		if (unlikely(dma_mapping_error(dev, pa)))
943 			goto dma_error;
944 		vring->ctx[i].mapped_as = wil_mapped_as_page;
945 		wil_tx_desc_map(d, pa, len, vring_index);
946 		/* no need to check return code -
947 		 * if it succeeded for 1-st descriptor,
948 		 * it will succeed here too
949 		 */
950 		wil_tx_desc_offload_cksum_set(wil, d, skb);
951 		*_d = *d;
952 	}
953 	/* for the last seg only */
954 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_EOP_POS);
955 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_MARK_WB_POS);
956 	d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_DMA_IT_POS);
957 	*_d = *d;
958 
959 	/* hold reference to skb
960 	 * to prevent skb release before accounting
961 	 * in case of immediate "tx done"
962 	 */
963 	vring->ctx[i].skb = skb_get(skb);
964 
965 	wil_hex_dump_txrx("Tx ", DUMP_PREFIX_NONE, 32, 4,
966 			  (const void *)d, sizeof(*d), false);
967 
968 	if (wil_vring_is_empty(vring)) /* performance monitoring */
969 		txdata->idle += get_cycles() - txdata->last_idle;
970 
971 	/* advance swhead */
972 	wil_vring_advance_head(vring, nr_frags + 1);
973 	wil_dbg_txrx(wil, "Tx swhead %d -> %d\n", swhead, vring->swhead);
974 	trace_wil6210_tx(vring_index, swhead, skb->len, nr_frags);
975 	iowrite32(vring->swhead, wil->csr + HOSTADDR(vring->hwtail));
976 
977 	return 0;
978  dma_error:
979 	/* unmap what we have mapped */
980 	nr_frags = f + 1; /* frags mapped + one for skb head */
981 	for (f = 0; f < nr_frags; f++) {
982 		struct wil_ctx *ctx;
983 
984 		i = (swhead + f) % vring->size;
985 		ctx = &vring->ctx[i];
986 		_d = &(vring->va[i].tx);
987 		*d = *_d;
988 		_d->dma.status = TX_DMA_STATUS_DU;
989 		wil_txdesc_unmap(dev, d, ctx);
990 
991 		if (ctx->skb)
992 			dev_kfree_skb_any(ctx->skb);
993 
994 		memset(ctx, 0, sizeof(*ctx));
995 	}
996 
997 	return -EINVAL;
998 }
999 
1000 
1001 netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
1002 {
1003 	struct wil6210_priv *wil = ndev_to_wil(ndev);
1004 	struct ethhdr *eth = (void *)skb->data;
1005 	struct vring *vring;
1006 	static bool pr_once_fw;
1007 	int rc;
1008 
1009 	wil_dbg_txrx(wil, "%s()\n", __func__);
1010 	if (!test_bit(wil_status_fwready, &wil->status)) {
1011 		if (!pr_once_fw) {
1012 			wil_err(wil, "FW not ready\n");
1013 			pr_once_fw = true;
1014 		}
1015 		goto drop;
1016 	}
1017 	if (!test_bit(wil_status_fwconnected, &wil->status)) {
1018 		wil_err(wil, "FW not connected\n");
1019 		goto drop;
1020 	}
1021 	if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
1022 		wil_err(wil, "Xmit in monitor mode not supported\n");
1023 		goto drop;
1024 	}
1025 	pr_once_fw = false;
1026 
1027 	/* find vring */
1028 	if (is_unicast_ether_addr(eth->h_dest)) {
1029 		vring = wil_find_tx_vring(wil, skb);
1030 	} else {
1031 		vring = wil_tx_bcast(wil, skb);
1032 	}
1033 	if (!vring) {
1034 		wil_dbg_txrx(wil, "No Tx VRING found for %pM\n", eth->h_dest);
1035 		goto drop;
1036 	}
1037 	/* set up vring entry */
1038 	rc = wil_tx_vring(wil, vring, skb);
1039 
1040 	/* do we still have enough room in the vring? */
1041 	if (wil_vring_avail_tx(vring) < wil_vring_wmark_low(vring)) {
1042 		netif_tx_stop_all_queues(wil_to_ndev(wil));
1043 		wil_dbg_txrx(wil, "netif_tx_stop : ring full\n");
1044 	}
1045 
1046 	switch (rc) {
1047 	case 0:
1048 		/* statistics will be updated on the tx_complete */
1049 		dev_kfree_skb_any(skb);
1050 		return NETDEV_TX_OK;
1051 	case -ENOMEM:
1052 		return NETDEV_TX_BUSY;
1053 	default:
1054 		break; /* goto drop; */
1055 	}
1056  drop:
1057 	ndev->stats.tx_dropped++;
1058 	dev_kfree_skb_any(skb);
1059 
1060 	return NET_XMIT_DROP;
1061 }
1062 
1063 /**
1064  * Clean up transmitted skb's from the Tx VRING
1065  *
1066  * Return number of descriptors cleared
1067  *
1068  * Safe to call from IRQ
1069  */
1070 int wil_tx_complete(struct wil6210_priv *wil, int ringid)
1071 {
1072 	struct net_device *ndev = wil_to_ndev(wil);
1073 	struct device *dev = wil_to_dev(wil);
1074 	struct vring *vring = &wil->vring_tx[ringid];
1075 	struct vring_tx_data *txdata = &wil->vring_tx_data[ringid];
1076 	int done = 0;
1077 	int cid = wil->vring2cid_tid[ringid][0];
1078 	struct wil_net_stats *stats = &wil->sta[cid].stats;
1079 	volatile struct vring_tx_desc *_d;
1080 
1081 	if (!vring->va) {
1082 		wil_err(wil, "Tx irq[%d]: vring not initialized\n", ringid);
1083 		return 0;
1084 	}
1085 
1086 	if (!txdata->enabled) {
1087 		wil_info(wil, "Tx irq[%d]: vring disabled\n", ringid);
1088 		return 0;
1089 	}
1090 
1091 	wil_dbg_txrx(wil, "%s(%d)\n", __func__, ringid);
1092 
1093 	while (!wil_vring_is_empty(vring)) {
1094 		int new_swtail;
1095 		struct wil_ctx *ctx = &vring->ctx[vring->swtail];
1096 		/**
1097 		 * For the fragmented skb, HW will set DU bit only for the
1098 		 * last fragment. look for it
1099 		 */
1100 		int lf = (vring->swtail + ctx->nr_frags) % vring->size;
1101 		/* TODO: check we are not past head */
1102 
1103 		_d = &vring->va[lf].tx;
1104 		if (!(_d->dma.status & TX_DMA_STATUS_DU))
1105 			break;
1106 
1107 		new_swtail = (lf + 1) % vring->size;
1108 		while (vring->swtail != new_swtail) {
1109 			struct vring_tx_desc dd, *d = &dd;
1110 			u16 dmalen;
1111 			struct sk_buff *skb;
1112 
1113 			ctx = &vring->ctx[vring->swtail];
1114 			skb = ctx->skb;
1115 			_d = &vring->va[vring->swtail].tx;
1116 
1117 			*d = *_d;
1118 
1119 			dmalen = le16_to_cpu(d->dma.length);
1120 			trace_wil6210_tx_done(ringid, vring->swtail, dmalen,
1121 					      d->dma.error);
1122 			wil_dbg_txrx(wil,
1123 				     "Tx[%3d] : %d bytes, status 0x%02x err 0x%02x\n",
1124 				     vring->swtail, dmalen, d->dma.status,
1125 				     d->dma.error);
1126 			wil_hex_dump_txrx("TxC ", DUMP_PREFIX_NONE, 32, 4,
1127 					  (const void *)d, sizeof(*d), false);
1128 
1129 			wil_txdesc_unmap(dev, d, ctx);
1130 
1131 			if (skb) {
1132 				if (d->dma.error == 0) {
1133 					ndev->stats.tx_packets++;
1134 					stats->tx_packets++;
1135 					ndev->stats.tx_bytes += skb->len;
1136 					stats->tx_bytes += skb->len;
1137 				} else {
1138 					ndev->stats.tx_errors++;
1139 					stats->tx_errors++;
1140 				}
1141 
1142 				dev_kfree_skb_any(skb);
1143 			}
1144 			memset(ctx, 0, sizeof(*ctx));
1145 			/* There is no need to touch HW descriptor:
1146 			 * - ststus bit TX_DMA_STATUS_DU is set by design,
1147 			 *   so hardware will not try to process this desc.,
1148 			 * - rest of descriptor will be initialized on Tx.
1149 			 */
1150 			vring->swtail = wil_vring_next_tail(vring);
1151 			done++;
1152 		}
1153 	}
1154 
1155 	if (wil_vring_is_empty(vring)) { /* performance monitoring */
1156 		wil_dbg_txrx(wil, "Ring[%2d] empty\n", ringid);
1157 		txdata->last_idle = get_cycles();
1158 	}
1159 
1160 	if (wil_vring_avail_tx(vring) > wil_vring_wmark_high(vring)) {
1161 		wil_dbg_txrx(wil, "netif_tx_wake : ring not full\n");
1162 		netif_tx_wake_all_queues(wil_to_ndev(wil));
1163 	}
1164 
1165 	return done;
1166 }
1167