Linux-libre 3.11-gnu
[librecmc/linux-libre.git] / drivers / net / wireless / ath / wil6210 / txrx.c
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
22 #include "wil6210.h"
23 #include "wmi.h"
24 #include "txrx.h"
25 #include "trace.h"
26
27 static bool rtap_include_phy_info;
28 module_param(rtap_include_phy_info, bool, S_IRUGO);
29 MODULE_PARM_DESC(rtap_include_phy_info,
30                  " Include PHY info in the radiotap header, default - no");
31
32 static inline int wil_vring_is_empty(struct vring *vring)
33 {
34         return vring->swhead == vring->swtail;
35 }
36
37 static inline u32 wil_vring_next_tail(struct vring *vring)
38 {
39         return (vring->swtail + 1) % vring->size;
40 }
41
42 static inline void wil_vring_advance_head(struct vring *vring, int n)
43 {
44         vring->swhead = (vring->swhead + n) % vring->size;
45 }
46
47 static inline int wil_vring_is_full(struct vring *vring)
48 {
49         return wil_vring_next_tail(vring) == vring->swhead;
50 }
51 /*
52  * Available space in Tx Vring
53  */
54 static inline int wil_vring_avail_tx(struct vring *vring)
55 {
56         u32 swhead = vring->swhead;
57         u32 swtail = vring->swtail;
58         int used = (vring->size + swhead - swtail) % vring->size;
59
60         return vring->size - used - 1;
61 }
62
63 static int wil_vring_alloc(struct wil6210_priv *wil, struct vring *vring)
64 {
65         struct device *dev = wil_to_dev(wil);
66         size_t sz = vring->size * sizeof(vring->va[0]);
67         uint i;
68
69         BUILD_BUG_ON(sizeof(vring->va[0]) != 32);
70
71         vring->swhead = 0;
72         vring->swtail = 0;
73         vring->ctx = kzalloc(vring->size * sizeof(vring->ctx[0]), GFP_KERNEL);
74         if (!vring->ctx) {
75                 vring->va = NULL;
76                 return -ENOMEM;
77         }
78         /*
79          * vring->va should be aligned on its size rounded up to power of 2
80          * This is granted by the dma_alloc_coherent
81          */
82         vring->va = dma_alloc_coherent(dev, sz, &vring->pa, GFP_KERNEL);
83         if (!vring->va) {
84                 kfree(vring->ctx);
85                 vring->ctx = NULL;
86                 return -ENOMEM;
87         }
88         /* initially, all descriptors are SW owned
89          * For Tx and Rx, ownership bit is at the same location, thus
90          * we can use any
91          */
92         for (i = 0; i < vring->size; i++) {
93                 volatile struct vring_tx_desc *_d = &(vring->va[i].tx);
94                 _d->dma.status = TX_DMA_STATUS_DU;
95         }
96
97         wil_dbg_misc(wil, "vring[%d] 0x%p:0x%016llx 0x%p\n", vring->size,
98                      vring->va, (unsigned long long)vring->pa, vring->ctx);
99
100         return 0;
101 }
102
103 static void wil_vring_free(struct wil6210_priv *wil, struct vring *vring,
104                            int tx)
105 {
106         struct device *dev = wil_to_dev(wil);
107         size_t sz = vring->size * sizeof(vring->va[0]);
108
109         while (!wil_vring_is_empty(vring)) {
110                 dma_addr_t pa;
111                 struct sk_buff *skb;
112                 u16 dmalen;
113
114                 if (tx) {
115                         struct vring_tx_desc dd, *d = &dd;
116                         volatile struct vring_tx_desc *_d =
117                                         &vring->va[vring->swtail].tx;
118
119                         *d = *_d;
120                         pa = wil_desc_addr(&d->dma.addr);
121                         dmalen = le16_to_cpu(d->dma.length);
122                         skb = vring->ctx[vring->swtail];
123                         if (skb) {
124                                 dma_unmap_single(dev, pa, dmalen,
125                                                  DMA_TO_DEVICE);
126                                 dev_kfree_skb_any(skb);
127                                 vring->ctx[vring->swtail] = NULL;
128                         } else {
129                                 dma_unmap_page(dev, pa, dmalen,
130                                                DMA_TO_DEVICE);
131                         }
132                         vring->swtail = wil_vring_next_tail(vring);
133                 } else { /* rx */
134                         struct vring_rx_desc dd, *d = &dd;
135                         volatile struct vring_rx_desc *_d =
136                                         &vring->va[vring->swtail].rx;
137
138                         *d = *_d;
139                         pa = wil_desc_addr(&d->dma.addr);
140                         dmalen = le16_to_cpu(d->dma.length);
141                         skb = vring->ctx[vring->swhead];
142                         dma_unmap_single(dev, pa, dmalen, DMA_FROM_DEVICE);
143                         kfree_skb(skb);
144                         wil_vring_advance_head(vring, 1);
145                 }
146         }
147         dma_free_coherent(dev, sz, (void *)vring->va, vring->pa);
148         kfree(vring->ctx);
149         vring->pa = 0;
150         vring->va = NULL;
151         vring->ctx = NULL;
152 }
153
154 /**
155  * Allocate one skb for Rx VRING
156  *
157  * Safe to call from IRQ
158  */
159 static int wil_vring_alloc_skb(struct wil6210_priv *wil, struct vring *vring,
160                                u32 i, int headroom)
161 {
162         struct device *dev = wil_to_dev(wil);
163         unsigned int sz = RX_BUF_LEN;
164         struct vring_rx_desc dd, *d = &dd;
165         volatile struct vring_rx_desc *_d = &(vring->va[i].rx);
166         dma_addr_t pa;
167
168         /* TODO align */
169         struct sk_buff *skb = dev_alloc_skb(sz + headroom);
170         if (unlikely(!skb))
171                 return -ENOMEM;
172
173         skb_reserve(skb, headroom);
174         skb_put(skb, sz);
175
176         pa = dma_map_single(dev, skb->data, skb->len, DMA_FROM_DEVICE);
177         if (unlikely(dma_mapping_error(dev, pa))) {
178                 kfree_skb(skb);
179                 return -ENOMEM;
180         }
181
182         d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
183         wil_desc_addr_set(&d->dma.addr, pa);
184         /* ip_length don't care */
185         /* b11 don't care */
186         /* error don't care */
187         d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
188         d->dma.length = cpu_to_le16(sz);
189         *_d = *d;
190         vring->ctx[i] = skb;
191
192         return 0;
193 }
194
195 /**
196  * Adds radiotap header
197  *
198  * Any error indicated as "Bad FCS"
199  *
200  * Vendor data for 04:ce:14-1 (Wilocity-1) consists of:
201  *  - Rx descriptor: 32 bytes
202  *  - Phy info
203  */
204 static void wil_rx_add_radiotap_header(struct wil6210_priv *wil,
205                                        struct sk_buff *skb)
206 {
207         struct wireless_dev *wdev = wil->wdev;
208         struct wil6210_rtap {
209                 struct ieee80211_radiotap_header rthdr;
210                 /* fields should be in the order of bits in rthdr.it_present */
211                 /* flags */
212                 u8 flags;
213                 /* channel */
214                 __le16 chnl_freq __aligned(2);
215                 __le16 chnl_flags;
216                 /* MCS */
217                 u8 mcs_present;
218                 u8 mcs_flags;
219                 u8 mcs_index;
220         } __packed;
221         struct wil6210_rtap_vendor {
222                 struct wil6210_rtap rtap;
223                 /* vendor */
224                 u8 vendor_oui[3] __aligned(2);
225                 u8 vendor_ns;
226                 __le16 vendor_skip;
227                 u8 vendor_data[0];
228         } __packed;
229         struct vring_rx_desc *d = wil_skb_rxdesc(skb);
230         struct wil6210_rtap_vendor *rtap_vendor;
231         int rtap_len = sizeof(struct wil6210_rtap);
232         int phy_length = 0; /* phy info header size, bytes */
233         static char phy_data[128];
234         struct ieee80211_channel *ch = wdev->preset_chandef.chan;
235
236         if (rtap_include_phy_info) {
237                 rtap_len = sizeof(*rtap_vendor) + sizeof(*d);
238                 /* calculate additional length */
239                 if (d->dma.status & RX_DMA_STATUS_PHY_INFO) {
240                         /**
241                          * PHY info starts from 8-byte boundary
242                          * there are 8-byte lines, last line may be partially
243                          * written (HW bug), thus FW configures for last line
244                          * to be excessive. Driver skips this last line.
245                          */
246                         int len = min_t(int, 8 + sizeof(phy_data),
247                                         wil_rxdesc_phy_length(d));
248                         if (len > 8) {
249                                 void *p = skb_tail_pointer(skb);
250                                 void *pa = PTR_ALIGN(p, 8);
251                                 if (skb_tailroom(skb) >= len + (pa - p)) {
252                                         phy_length = len - 8;
253                                         memcpy(phy_data, pa, phy_length);
254                                 }
255                         }
256                 }
257                 rtap_len += phy_length;
258         }
259
260         if (skb_headroom(skb) < rtap_len &&
261             pskb_expand_head(skb, rtap_len, 0, GFP_ATOMIC)) {
262                 wil_err(wil, "Unable to expand headrom to %d\n", rtap_len);
263                 return;
264         }
265
266         rtap_vendor = (void *)skb_push(skb, rtap_len);
267         memset(rtap_vendor, 0, rtap_len);
268
269         rtap_vendor->rtap.rthdr.it_version = PKTHDR_RADIOTAP_VERSION;
270         rtap_vendor->rtap.rthdr.it_len = cpu_to_le16(rtap_len);
271         rtap_vendor->rtap.rthdr.it_present = cpu_to_le32(
272                         (1 << IEEE80211_RADIOTAP_FLAGS) |
273                         (1 << IEEE80211_RADIOTAP_CHANNEL) |
274                         (1 << IEEE80211_RADIOTAP_MCS));
275         if (d->dma.status & RX_DMA_STATUS_ERROR)
276                 rtap_vendor->rtap.flags |= IEEE80211_RADIOTAP_F_BADFCS;
277
278         rtap_vendor->rtap.chnl_freq = cpu_to_le16(ch ? ch->center_freq : 58320);
279         rtap_vendor->rtap.chnl_flags = cpu_to_le16(0);
280
281         rtap_vendor->rtap.mcs_present = IEEE80211_RADIOTAP_MCS_HAVE_MCS;
282         rtap_vendor->rtap.mcs_flags = 0;
283         rtap_vendor->rtap.mcs_index = wil_rxdesc_mcs(d);
284
285         if (rtap_include_phy_info) {
286                 rtap_vendor->rtap.rthdr.it_present |= cpu_to_le32(1 <<
287                                 IEEE80211_RADIOTAP_VENDOR_NAMESPACE);
288                 /* OUI for Wilocity 04:ce:14 */
289                 rtap_vendor->vendor_oui[0] = 0x04;
290                 rtap_vendor->vendor_oui[1] = 0xce;
291                 rtap_vendor->vendor_oui[2] = 0x14;
292                 rtap_vendor->vendor_ns = 1;
293                 /* Rx descriptor + PHY data  */
294                 rtap_vendor->vendor_skip = cpu_to_le16(sizeof(*d) +
295                                                        phy_length);
296                 memcpy(rtap_vendor->vendor_data, (void *)d, sizeof(*d));
297                 memcpy(rtap_vendor->vendor_data + sizeof(*d), phy_data,
298                        phy_length);
299         }
300 }
301
302 /*
303  * Fast swap in place between 2 registers
304  */
305 static void wil_swap_u16(u16 *a, u16 *b)
306 {
307         *a ^= *b;
308         *b ^= *a;
309         *a ^= *b;
310 }
311
312 static void wil_swap_ethaddr(void *data)
313 {
314         struct ethhdr *eth = data;
315         u16 *s = (u16 *)eth->h_source;
316         u16 *d = (u16 *)eth->h_dest;
317
318         wil_swap_u16(s++, d++);
319         wil_swap_u16(s++, d++);
320         wil_swap_u16(s, d);
321 }
322
323 /**
324  * reap 1 frame from @swhead
325  *
326  * Rx descriptor copied to skb->cb
327  *
328  * Safe to call from IRQ
329  */
330 static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
331                                          struct vring *vring)
332 {
333         struct device *dev = wil_to_dev(wil);
334         struct net_device *ndev = wil_to_ndev(wil);
335         volatile struct vring_rx_desc *_d;
336         struct vring_rx_desc *d;
337         struct sk_buff *skb;
338         dma_addr_t pa;
339         unsigned int sz = RX_BUF_LEN;
340         u16 dmalen;
341         u8 ftype;
342         u8 ds_bits;
343
344         BUILD_BUG_ON(sizeof(struct vring_rx_desc) > sizeof(skb->cb));
345
346         if (wil_vring_is_empty(vring))
347                 return NULL;
348
349         _d = &(vring->va[vring->swhead].rx);
350         if (!(_d->dma.status & RX_DMA_STATUS_DU)) {
351                 /* it is not error, we just reached end of Rx done area */
352                 return NULL;
353         }
354
355         skb = vring->ctx[vring->swhead];
356         d = wil_skb_rxdesc(skb);
357         *d = *_d;
358         pa = wil_desc_addr(&d->dma.addr);
359         vring->ctx[vring->swhead] = NULL;
360         wil_vring_advance_head(vring, 1);
361
362         dma_unmap_single(dev, pa, sz, DMA_FROM_DEVICE);
363         dmalen = le16_to_cpu(d->dma.length);
364
365         trace_wil6210_rx(vring->swhead, d);
366         wil_dbg_txrx(wil, "Rx[%3d] : %d bytes\n", vring->swhead, dmalen);
367         wil_hex_dump_txrx("Rx ", DUMP_PREFIX_NONE, 32, 4,
368                           (const void *)d, sizeof(*d), false);
369
370         if (dmalen > sz) {
371                 wil_err(wil, "Rx size too large: %d bytes!\n", dmalen);
372                 kfree_skb(skb);
373                 return NULL;
374         }
375         skb_trim(skb, dmalen);
376
377         wil_hex_dump_txrx("Rx ", DUMP_PREFIX_OFFSET, 16, 1,
378                           skb->data, skb_headlen(skb), false);
379
380
381         wil->stats.last_mcs_rx = wil_rxdesc_mcs(d);
382
383         /* use radiotap header only if required */
384         if (ndev->type == ARPHRD_IEEE80211_RADIOTAP)
385                 wil_rx_add_radiotap_header(wil, skb);
386
387         /* no extra checks if in sniffer mode */
388         if (ndev->type != ARPHRD_ETHER)
389                 return skb;
390         /*
391          * Non-data frames may be delivered through Rx DMA channel (ex: BAR)
392          * Driver should recognize it by frame type, that is found
393          * in Rx descriptor. If type is not data, it is 802.11 frame as is
394          */
395         ftype = wil_rxdesc_ftype(d) << 2;
396         if (ftype != IEEE80211_FTYPE_DATA) {
397                 wil_dbg_txrx(wil, "Non-data frame ftype 0x%08x\n", ftype);
398                 /* TODO: process it */
399                 kfree_skb(skb);
400                 return NULL;
401         }
402
403         if (skb->len < ETH_HLEN) {
404                 wil_err(wil, "Short frame, len = %d\n", skb->len);
405                 /* TODO: process it (i.e. BAR) */
406                 kfree_skb(skb);
407                 return NULL;
408         }
409
410         ds_bits = wil_rxdesc_ds_bits(d);
411         if (ds_bits == 1) {
412                 /*
413                  * HW bug - in ToDS mode, i.e. Rx on AP side,
414                  * addresses get swapped
415                  */
416                 wil_swap_ethaddr(skb->data);
417         }
418
419         return skb;
420 }
421
422 /**
423  * allocate and fill up to @count buffers in rx ring
424  * buffers posted at @swtail
425  */
426 static int wil_rx_refill(struct wil6210_priv *wil, int count)
427 {
428         struct net_device *ndev = wil_to_ndev(wil);
429         struct vring *v = &wil->vring_rx;
430         u32 next_tail;
431         int rc = 0;
432         int headroom = ndev->type == ARPHRD_IEEE80211_RADIOTAP ?
433                         WIL6210_RTAP_SIZE : 0;
434
435         for (; next_tail = wil_vring_next_tail(v),
436                         (next_tail != v->swhead) && (count-- > 0);
437                         v->swtail = next_tail) {
438                 rc = wil_vring_alloc_skb(wil, v, v->swtail, headroom);
439                 if (rc) {
440                         wil_err(wil, "Error %d in wil_rx_refill[%d]\n",
441                                 rc, v->swtail);
442                         break;
443                 }
444         }
445         iowrite32(v->swtail, wil->csr + HOSTADDR(v->hwtail));
446
447         return rc;
448 }
449
450 /*
451  * Pass Rx packet to the netif. Update statistics.
452  * Called in softirq context (NAPI poll).
453  */
454 static void wil_netif_rx_any(struct sk_buff *skb, struct net_device *ndev)
455 {
456         int rc;
457         unsigned int len = skb->len;
458
459         skb_orphan(skb);
460
461         rc = netif_receive_skb(skb);
462
463         if (likely(rc == NET_RX_SUCCESS)) {
464                 ndev->stats.rx_packets++;
465                 ndev->stats.rx_bytes += len;
466
467         } else {
468                 ndev->stats.rx_dropped++;
469         }
470 }
471
472 /**
473  * Proceed all completed skb's from Rx VRING
474  *
475  * Safe to call from NAPI poll, i.e. softirq with interrupts enabled
476  */
477 void wil_rx_handle(struct wil6210_priv *wil, int *quota)
478 {
479         struct net_device *ndev = wil_to_ndev(wil);
480         struct vring *v = &wil->vring_rx;
481         struct sk_buff *skb;
482
483         if (!v->va) {
484                 wil_err(wil, "Rx IRQ while Rx not yet initialized\n");
485                 return;
486         }
487         wil_dbg_txrx(wil, "%s()\n", __func__);
488         while ((*quota > 0) && (NULL != (skb = wil_vring_reap_rx(wil, v)))) {
489                 (*quota)--;
490
491                 if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
492                         skb->dev = ndev;
493                         skb_reset_mac_header(skb);
494                         skb->ip_summed = CHECKSUM_UNNECESSARY;
495                         skb->pkt_type = PACKET_OTHERHOST;
496                         skb->protocol = htons(ETH_P_802_2);
497
498                 } else {
499                         skb->protocol = eth_type_trans(skb, ndev);
500                 }
501
502                 wil_netif_rx_any(skb, ndev);
503         }
504         wil_rx_refill(wil, v->size);
505 }
506
507 int wil_rx_init(struct wil6210_priv *wil)
508 {
509         struct vring *vring = &wil->vring_rx;
510         int rc;
511
512         vring->size = WIL6210_RX_RING_SIZE;
513         rc = wil_vring_alloc(wil, vring);
514         if (rc)
515                 return rc;
516
517         rc = wmi_rx_chain_add(wil, vring);
518         if (rc)
519                 goto err_free;
520
521         rc = wil_rx_refill(wil, vring->size);
522         if (rc)
523                 goto err_free;
524
525         return 0;
526  err_free:
527         wil_vring_free(wil, vring, 0);
528
529         return rc;
530 }
531
532 void wil_rx_fini(struct wil6210_priv *wil)
533 {
534         struct vring *vring = &wil->vring_rx;
535
536         if (vring->va)
537                 wil_vring_free(wil, vring, 0);
538 }
539
540 int wil_vring_init_tx(struct wil6210_priv *wil, int id, int size,
541                       int cid, int tid)
542 {
543         int rc;
544         struct wmi_vring_cfg_cmd cmd = {
545                 .action = cpu_to_le32(WMI_VRING_CMD_ADD),
546                 .vring_cfg = {
547                         .tx_sw_ring = {
548                                 .max_mpdu_size = cpu_to_le16(TX_BUF_LEN),
549                                 .ring_size = cpu_to_le16(size),
550                         },
551                         .ringid = id,
552                         .cidxtid = (cid & 0xf) | ((tid & 0xf) << 4),
553                         .encap_trans_type = WMI_VRING_ENC_TYPE_802_3,
554                         .mac_ctrl = 0,
555                         .to_resolution = 0,
556                         .agg_max_wsize = 16,
557                         .schd_params = {
558                                 .priority = cpu_to_le16(0),
559                                 .timeslot_us = cpu_to_le16(0xfff),
560                         },
561                 },
562         };
563         struct {
564                 struct wil6210_mbox_hdr_wmi wmi;
565                 struct wmi_vring_cfg_done_event cmd;
566         } __packed reply;
567         struct vring *vring = &wil->vring_tx[id];
568
569         if (vring->va) {
570                 wil_err(wil, "Tx ring [%d] already allocated\n", id);
571                 rc = -EINVAL;
572                 goto out;
573         }
574
575         vring->size = size;
576         rc = wil_vring_alloc(wil, vring);
577         if (rc)
578                 goto out;
579
580         cmd.vring_cfg.tx_sw_ring.ring_mem_base = cpu_to_le64(vring->pa);
581
582         rc = wmi_call(wil, WMI_VRING_CFG_CMDID, &cmd, sizeof(cmd),
583                       WMI_VRING_CFG_DONE_EVENTID, &reply, sizeof(reply), 100);
584         if (rc)
585                 goto out_free;
586
587         if (reply.cmd.status != WMI_FW_STATUS_SUCCESS) {
588                 wil_err(wil, "Tx config failed, status 0x%02x\n",
589                         reply.cmd.status);
590                 rc = -EINVAL;
591                 goto out_free;
592         }
593         vring->hwtail = le32_to_cpu(reply.cmd.tx_vring_tail_ptr);
594
595         return 0;
596  out_free:
597         wil_vring_free(wil, vring, 1);
598  out:
599
600         return rc;
601 }
602
603 void wil_vring_fini_tx(struct wil6210_priv *wil, int id)
604 {
605         struct vring *vring = &wil->vring_tx[id];
606
607         if (!vring->va)
608                 return;
609
610         wil_vring_free(wil, vring, 1);
611 }
612
613 static struct vring *wil_find_tx_vring(struct wil6210_priv *wil,
614                                        struct sk_buff *skb)
615 {
616         struct vring *v = &wil->vring_tx[0];
617
618         if (v->va)
619                 return v;
620
621         return NULL;
622 }
623
624 static int wil_tx_desc_map(struct vring_tx_desc *d, dma_addr_t pa, u32 len,
625                            int vring_index)
626 {
627         wil_desc_addr_set(&d->dma.addr, pa);
628         d->dma.ip_length = 0;
629         /* 0..6: mac_length; 7:ip_version 0-IP6 1-IP4*/
630         d->dma.b11 = 0/*14 | BIT(7)*/;
631         d->dma.error = 0;
632         d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
633         d->dma.length = cpu_to_le16((u16)len);
634         d->dma.d0 = (vring_index << DMA_CFG_DESC_TX_0_QID_POS);
635         d->mac.d[0] = 0;
636         d->mac.d[1] = 0;
637         d->mac.d[2] = 0;
638         d->mac.ucode_cmd = 0;
639         /* use dst index 0 */
640         d->mac.d[1] |= BIT(MAC_CFG_DESC_TX_1_DST_INDEX_EN_POS) |
641                        (0 << MAC_CFG_DESC_TX_1_DST_INDEX_POS);
642         /* translation type:  0 - bypass; 1 - 802.3; 2 - native wifi */
643         d->mac.d[2] = BIT(MAC_CFG_DESC_TX_2_SNAP_HDR_INSERTION_EN_POS) |
644                       (1 << MAC_CFG_DESC_TX_2_L2_TRANSLATION_TYPE_POS);
645
646         return 0;
647 }
648
649 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
650                         struct sk_buff *skb)
651 {
652         struct device *dev = wil_to_dev(wil);
653         struct vring_tx_desc dd, *d = &dd;
654         volatile struct vring_tx_desc *_d;
655         u32 swhead = vring->swhead;
656         int avail = wil_vring_avail_tx(vring);
657         int nr_frags = skb_shinfo(skb)->nr_frags;
658         uint f;
659         int vring_index = vring - wil->vring_tx;
660         uint i = swhead;
661         dma_addr_t pa;
662
663         wil_dbg_txrx(wil, "%s()\n", __func__);
664
665         if (avail < vring->size/8)
666                 netif_tx_stop_all_queues(wil_to_ndev(wil));
667         if (avail < 1 + nr_frags) {
668                 wil_err(wil, "Tx ring full. No space for %d fragments\n",
669                         1 + nr_frags);
670                 return -ENOMEM;
671         }
672         _d = &(vring->va[i].tx);
673
674         /* FIXME FW can accept only unicast frames for the peer */
675         memcpy(skb->data, wil->dst_addr[vring_index], ETH_ALEN);
676
677         pa = dma_map_single(dev, skb->data,
678                         skb_headlen(skb), DMA_TO_DEVICE);
679
680         wil_dbg_txrx(wil, "Tx skb %d bytes %p -> %#08llx\n", skb_headlen(skb),
681                      skb->data, (unsigned long long)pa);
682         wil_hex_dump_txrx("Tx ", DUMP_PREFIX_OFFSET, 16, 1,
683                           skb->data, skb_headlen(skb), false);
684
685         if (unlikely(dma_mapping_error(dev, pa)))
686                 return -EINVAL;
687         /* 1-st segment */
688         wil_tx_desc_map(d, pa, skb_headlen(skb), vring_index);
689         d->mac.d[2] |= ((nr_frags + 1) <<
690                        MAC_CFG_DESC_TX_2_NUM_OF_DESCRIPTORS_POS);
691         if (nr_frags)
692                 *_d = *d;
693
694         /* middle segments */
695         for (f = 0; f < nr_frags; f++) {
696                 const struct skb_frag_struct *frag =
697                                 &skb_shinfo(skb)->frags[f];
698                 int len = skb_frag_size(frag);
699                 i = (swhead + f + 1) % vring->size;
700                 _d = &(vring->va[i].tx);
701                 pa = skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag),
702                                 DMA_TO_DEVICE);
703                 if (unlikely(dma_mapping_error(dev, pa)))
704                         goto dma_error;
705                 wil_tx_desc_map(d, pa, len, vring_index);
706                 vring->ctx[i] = NULL;
707                 *_d = *d;
708         }
709         /* for the last seg only */
710         d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_EOP_POS);
711         d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_MARK_WB_POS);
712         d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_DMA_IT_POS);
713         *_d = *d;
714
715         wil_hex_dump_txrx("Tx ", DUMP_PREFIX_NONE, 32, 4,
716                           (const void *)d, sizeof(*d), false);
717
718         /* advance swhead */
719         wil_vring_advance_head(vring, nr_frags + 1);
720         wil_dbg_txrx(wil, "Tx swhead %d -> %d\n", swhead, vring->swhead);
721         trace_wil6210_tx(vring_index, swhead, skb->len, nr_frags);
722         iowrite32(vring->swhead, wil->csr + HOSTADDR(vring->hwtail));
723         /* hold reference to skb
724          * to prevent skb release before accounting
725          * in case of immediate "tx done"
726          */
727         vring->ctx[i] = skb_get(skb);
728
729         return 0;
730  dma_error:
731         /* unmap what we have mapped */
732         /* Note: increment @f to operate with positive index */
733         for (f++; f > 0; f--) {
734                 u16 dmalen;
735
736                 i = (swhead + f) % vring->size;
737                 _d = &(vring->va[i].tx);
738                 *d = *_d;
739                 _d->dma.status = TX_DMA_STATUS_DU;
740                 pa = wil_desc_addr(&d->dma.addr);
741                 dmalen = le16_to_cpu(d->dma.length);
742                 if (vring->ctx[i])
743                         dma_unmap_single(dev, pa, dmalen, DMA_TO_DEVICE);
744                 else
745                         dma_unmap_page(dev, pa, dmalen, DMA_TO_DEVICE);
746         }
747
748         return -EINVAL;
749 }
750
751
752 netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
753 {
754         struct wil6210_priv *wil = ndev_to_wil(ndev);
755         struct vring *vring;
756         int rc;
757
758         wil_dbg_txrx(wil, "%s()\n", __func__);
759         if (!test_bit(wil_status_fwready, &wil->status)) {
760                 wil_err(wil, "FW not ready\n");
761                 goto drop;
762         }
763         if (!test_bit(wil_status_fwconnected, &wil->status)) {
764                 wil_err(wil, "FW not connected\n");
765                 goto drop;
766         }
767         if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
768                 wil_err(wil, "Xmit in monitor mode not supported\n");
769                 goto drop;
770         }
771
772         /* find vring */
773         vring = wil_find_tx_vring(wil, skb);
774         if (!vring) {
775                 wil_err(wil, "No Tx VRING available\n");
776                 goto drop;
777         }
778         /* set up vring entry */
779         rc = wil_tx_vring(wil, vring, skb);
780
781         switch (rc) {
782         case 0:
783                 /* statistics will be updated on the tx_complete */
784                 dev_kfree_skb_any(skb);
785                 return NETDEV_TX_OK;
786         case -ENOMEM:
787                 return NETDEV_TX_BUSY;
788         default:
789                 break; /* goto drop; */
790         }
791  drop:
792         ndev->stats.tx_dropped++;
793         dev_kfree_skb_any(skb);
794
795         return NET_XMIT_DROP;
796 }
797
798 /**
799  * Clean up transmitted skb's from the Tx VRING
800  *
801  * Return number of descriptors cleared
802  *
803  * Safe to call from IRQ
804  */
805 int wil_tx_complete(struct wil6210_priv *wil, int ringid)
806 {
807         struct net_device *ndev = wil_to_ndev(wil);
808         struct device *dev = wil_to_dev(wil);
809         struct vring *vring = &wil->vring_tx[ringid];
810         int done = 0;
811
812         if (!vring->va) {
813                 wil_err(wil, "Tx irq[%d]: vring not initialized\n", ringid);
814                 return 0;
815         }
816
817         wil_dbg_txrx(wil, "%s(%d)\n", __func__, ringid);
818
819         while (!wil_vring_is_empty(vring)) {
820                 volatile struct vring_tx_desc *_d =
821                                               &vring->va[vring->swtail].tx;
822                 struct vring_tx_desc dd, *d = &dd;
823                 dma_addr_t pa;
824                 struct sk_buff *skb;
825                 u16 dmalen;
826
827                 *d = *_d;
828
829                 if (!(d->dma.status & TX_DMA_STATUS_DU))
830                         break;
831
832                 dmalen = le16_to_cpu(d->dma.length);
833                 trace_wil6210_tx_done(ringid, vring->swtail, dmalen,
834                                       d->dma.error);
835                 wil_dbg_txrx(wil,
836                              "Tx[%3d] : %d bytes, status 0x%02x err 0x%02x\n",
837                              vring->swtail, dmalen, d->dma.status,
838                              d->dma.error);
839                 wil_hex_dump_txrx("TxC ", DUMP_PREFIX_NONE, 32, 4,
840                                   (const void *)d, sizeof(*d), false);
841
842                 pa = wil_desc_addr(&d->dma.addr);
843                 skb = vring->ctx[vring->swtail];
844                 if (skb) {
845                         if (d->dma.error == 0) {
846                                 ndev->stats.tx_packets++;
847                                 ndev->stats.tx_bytes += skb->len;
848                         } else {
849                                 ndev->stats.tx_errors++;
850                         }
851
852                         dma_unmap_single(dev, pa, dmalen, DMA_TO_DEVICE);
853                         dev_kfree_skb_any(skb);
854                         vring->ctx[vring->swtail] = NULL;
855                 } else {
856                         dma_unmap_page(dev, pa, dmalen, DMA_TO_DEVICE);
857                 }
858                 d->dma.addr.addr_low = 0;
859                 d->dma.addr.addr_high = 0;
860                 d->dma.length = 0;
861                 d->dma.status = TX_DMA_STATUS_DU;
862                 vring->swtail = wil_vring_next_tail(vring);
863                 done++;
864         }
865         if (wil_vring_avail_tx(vring) > vring->size/4)
866                 netif_tx_wake_all_queues(wil_to_ndev(wil));
867
868         return done;
869 }