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
  26 static bool rtap_include_phy_info;
  27 module_param(rtap_include_phy_info, bool, S_IRUGO);
  28 MODULE_PARM_DESC(rtap_include_phy_info,
  29                  " Include PHY info in the radiotap header, default - no");
  30
  31 static inline int wil_vring_is_empty(struct vring *vring)
  32 {
  33         return vring->swhead == vring->swtail;
  34 }
  35
  36 static inline u32 wil_vring_next_tail(struct vring *vring)
  37 {
  38         return (vring->swtail + 1) % vring->size;
  39 }
  40
  41 static inline void wil_vring_advance_head(struct vring *vring, int n)
  42 {
  43         vring->swhead = (vring->swhead + n) % vring->size;
  44 }
  45
  46 static inline int wil_vring_is_full(struct vring *vring)
  47 {
  48         return wil_vring_next_tail(vring) == vring->swhead;
  49 }
  50 /*
  51  * Available space in Tx Vring
  52  */
  53 static inline int wil_vring_avail_tx(struct vring *vring)
  54 {
  55         u32 swhead = vring->swhead;
  56         u32 swtail = vring->swtail;
  57         int used = (vring->size + swhead - swtail) % vring->size;
  58
  59         return vring->size - used - 1;
  60 }
  61
  62 static int wil_vring_alloc(struct wil6210_priv *wil, struct vring *vring)
  63 {
  64         struct device *dev = wil_to_dev(wil);
  65         size_t sz = vring->size * sizeof(vring->va[0]);
  66         uint i;
  67
  68         BUILD_BUG_ON(sizeof(vring->va[0]) != 32);
  69
  70         vring->swhead = 0;
  71         vring->swtail = 0;
  72         vring->ctx = kzalloc(vring->size * sizeof(vring->ctx[0]), GFP_KERNEL);
  73         if (!vring->ctx) {
  74                 vring->va = NULL;
  75                 return -ENOMEM;
  76         }
  77         /*
  78          * vring->va should be aligned on its size rounded up to power of 2
  79          * This is granted by the dma_alloc_coherent
  80          */
  81         vring->va = dma_alloc_coherent(dev, sz, &vring->pa, GFP_KERNEL);
  82         if (!vring->va) {
  83                 kfree(vring->ctx);
  84                 vring->ctx = NULL;
  85                 return -ENOMEM;
  86         }
  87         /* initially, all descriptors are SW owned
  88          * For Tx and Rx, ownership bit is at the same location, thus
  89          * we can use any
  90          */
  91         for (i = 0; i < vring->size; i++) {
  92                 volatile struct vring_tx_desc *d = &(vring->va[i].tx);
  93                 d->dma.status = TX_DMA_STATUS_DU;
  94         }
  95
  96         wil_dbg_misc(wil, "vring[%d] 0x%p:0x%016llx 0x%p\n", vring->size,
  97                      vring->va, (unsigned long long)vring->pa, vring->ctx);
  98
  99         return 0;
 100 }
 101
 102 static void wil_vring_free(struct wil6210_priv *wil, struct vring *vring,
 103                            int tx)
 104 {
 105         struct device *dev = wil_to_dev(wil);
 106         size_t sz = vring->size * sizeof(vring->va[0]);
 107
 108         while (!wil_vring_is_empty(vring)) {
 109                 u16 dmalen;
 110                 if (tx) {
 111                         volatile struct vring_tx_desc *d =
 112                                         &vring->va[vring->swtail].tx;
 113                         dma_addr_t pa = d->dma.addr_low |
 114                                         ((u64)d->dma.addr_high << 32);
 115                         struct sk_buff *skb = vring->ctx[vring->swtail];
 116                         dmalen = le16_to_cpu(d->dma.length);
 117                         if (skb) {
 118                                 dma_unmap_single(dev, pa, dmalen,
 119                                                  DMA_TO_DEVICE);
 120                                 dev_kfree_skb_any(skb);
 121                                 vring->ctx[vring->swtail] = NULL;
 122                         } else {
 123                                 dma_unmap_page(dev, pa, dmalen,
 124                                                DMA_TO_DEVICE);
 125                         }
 126                         vring->swtail = wil_vring_next_tail(vring);
 127                 } else { /* rx */
 128                         volatile struct vring_rx_desc *d =
 129                                         &vring->va[vring->swtail].rx;
 130                         dma_addr_t pa = d->dma.addr_low |
 131                                         ((u64)d->dma.addr_high << 32);
 132                         struct sk_buff *skb = vring->ctx[vring->swhead];
 133                         dmalen = le16_to_cpu(d->dma.length);
 134                         dma_unmap_single(dev, pa, dmalen, DMA_FROM_DEVICE);
 135                         kfree_skb(skb);
 136                         wil_vring_advance_head(vring, 1);
 137                 }
 138         }
 139         dma_free_coherent(dev, sz, (void *)vring->va, vring->pa);
 140         kfree(vring->ctx);
 141         vring->pa = 0;
 142         vring->va = NULL;
 143         vring->ctx = NULL;
 144 }
 145
 146 /**
 147  * Allocate one skb for Rx VRING
 148  *
 149  * Safe to call from IRQ
 150  */
 151 static int wil_vring_alloc_skb(struct wil6210_priv *wil, struct vring *vring,
 152                                u32 i, int headroom)
 153 {
 154         struct device *dev = wil_to_dev(wil);
 155         unsigned int sz = RX_BUF_LEN;
 156         volatile struct vring_rx_desc *d = &(vring->va[i].rx);
 157         dma_addr_t pa;
 158
 159         /* TODO align */
 160         struct sk_buff *skb = dev_alloc_skb(sz + headroom);
 161         if (unlikely(!skb))
 162                 return -ENOMEM;
 163
 164         skb_reserve(skb, headroom);
 165         skb_put(skb, sz);
 166
 167         pa = dma_map_single(dev, skb->data, skb->len, DMA_FROM_DEVICE);
 168         if (unlikely(dma_mapping_error(dev, pa))) {
 169                 kfree_skb(skb);
 170                 return -ENOMEM;
 171         }
 172
 173         d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
 174         d->dma.addr_low = lower_32_bits(pa);
 175         d->dma.addr_high = (u16)upper_32_bits(pa);
 176         /* ip_length don't care */
 177         /* b11 don't care */
 178         /* error don't care */
 179         d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
 180         d->dma.length = cpu_to_le16(sz);
 181         vring->ctx[i] = skb;
 182
 183         return 0;
 184 }
 185
 186 /**
 187  * Adds radiotap header
 188  *
 189  * Any error indicated as "Bad FCS"
 190  *
 191  * Vendor data for 04:ce:14-1 (Wilocity-1) consists of:
 192  *  - Rx descriptor: 32 bytes
 193  *  - Phy info
 194  */
 195 static void wil_rx_add_radiotap_header(struct wil6210_priv *wil,
 196                                        struct sk_buff *skb)
 197 {
 198         struct wireless_dev *wdev = wil->wdev;
 199         struct wil6210_rtap {
 200                 struct ieee80211_radiotap_header rthdr;
 201                 /* fields should be in the order of bits in rthdr.it_present */
 202                 /* flags */
 203                 u8 flags;
 204                 /* channel */
 205                 __le16 chnl_freq __aligned(2);
 206                 __le16 chnl_flags;
 207                 /* MCS */
 208                 u8 mcs_present;
 209                 u8 mcs_flags;
 210                 u8 mcs_index;
 211         } __packed;
 212         struct wil6210_rtap_vendor {
 213                 struct wil6210_rtap rtap;
 214                 /* vendor */
 215                 u8 vendor_oui[3] __aligned(2);
 216                 u8 vendor_ns;
 217                 __le16 vendor_skip;
 218                 u8 vendor_data[0];
 219         } __packed;
 220         struct vring_rx_desc *d = wil_skb_rxdesc(skb);
 221         struct wil6210_rtap_vendor *rtap_vendor;
 222         int rtap_len = sizeof(struct wil6210_rtap);
 223         int phy_length = 0; /* phy info header size, bytes */
 224         static char phy_data[128];
 225         struct ieee80211_channel *ch = wdev->preset_chandef.chan;
 226
 227         if (rtap_include_phy_info) {
 228                 rtap_len = sizeof(*rtap_vendor) + sizeof(*d);
 229                 /* calculate additional length */
 230                 if (d->dma.status & RX_DMA_STATUS_PHY_INFO) {
 231                         /**
 232                          * PHY info starts from 8-byte boundary
 233                          * there are 8-byte lines, last line may be partially
 234                          * written (HW bug), thus FW configures for last line
 235                          * to be excessive. Driver skips this last line.
 236                          */
 237                         int len = min_t(int, 8 + sizeof(phy_data),
 238                                         wil_rxdesc_phy_length(d));
 239                         if (len > 8) {
 240                                 void *p = skb_tail_pointer(skb);
 241                                 void *pa = PTR_ALIGN(p, 8);
 242                                 if (skb_tailroom(skb) >= len + (pa - p)) {
 243                                         phy_length = len - 8;
 244                                         memcpy(phy_data, pa, phy_length);
 245                                 }
 246                         }
 247                 }
 248                 rtap_len += phy_length;
 249         }
 250
 251         if (skb_headroom(skb) < rtap_len &&
 252             pskb_expand_head(skb, rtap_len, 0, GFP_ATOMIC)) {
 253                 wil_err(wil, "Unable to expand headrom to %d\n", rtap_len);
 254                 return;
 255         }
 256
 257         rtap_vendor = (void *)skb_push(skb, rtap_len);
 258         memset(rtap_vendor, 0, rtap_len);
 259
 260         rtap_vendor->rtap.rthdr.it_version = PKTHDR_RADIOTAP_VERSION;
 261         rtap_vendor->rtap.rthdr.it_len = cpu_to_le16(rtap_len);
 262         rtap_vendor->rtap.rthdr.it_present = cpu_to_le32(
 263                         (1 << IEEE80211_RADIOTAP_FLAGS) |
 264                         (1 << IEEE80211_RADIOTAP_CHANNEL) |
 265                         (1 << IEEE80211_RADIOTAP_MCS));
 266         if (d->dma.status & RX_DMA_STATUS_ERROR)
 267                 rtap_vendor->rtap.flags |= IEEE80211_RADIOTAP_F_BADFCS;
 268
 269         rtap_vendor->rtap.chnl_freq = cpu_to_le16(ch ? ch->center_freq : 58320);
 270         rtap_vendor->rtap.chnl_flags = cpu_to_le16(0);
 271
 272         rtap_vendor->rtap.mcs_present = IEEE80211_RADIOTAP_MCS_HAVE_MCS;
 273         rtap_vendor->rtap.mcs_flags = 0;
 274         rtap_vendor->rtap.mcs_index = wil_rxdesc_mcs(d);
 275
 276         if (rtap_include_phy_info) {
 277                 rtap_vendor->rtap.rthdr.it_present |= cpu_to_le32(1 <<
 278                                 IEEE80211_RADIOTAP_VENDOR_NAMESPACE);
 279                 /* OUI for Wilocity 04:ce:14 */
 280                 rtap_vendor->vendor_oui[0] = 0x04;
 281                 rtap_vendor->vendor_oui[1] = 0xce;
 282                 rtap_vendor->vendor_oui[2] = 0x14;
 283                 rtap_vendor->vendor_ns = 1;
 284                 /* Rx descriptor + PHY data  */
 285                 rtap_vendor->vendor_skip = cpu_to_le16(sizeof(*d) +
 286                                                        phy_length);
 287                 memcpy(rtap_vendor->vendor_data, (void *)d, sizeof(*d));
 288                 memcpy(rtap_vendor->vendor_data + sizeof(*d), phy_data,
 289                        phy_length);
 290         }
 291 }
 292
 293 /*
 294  * Fast swap in place between 2 registers
 295  */
 296 static void wil_swap_u16(u16 *a, u16 *b)
 297 {
 298         *a ^= *b;
 299         *b ^= *a;
 300         *a ^= *b;
 301 }
 302
 303 static void wil_swap_ethaddr(void *data)
 304 {
 305         struct ethhdr *eth = data;
 306         u16 *s = (u16 *)eth->h_source;
 307         u16 *d = (u16 *)eth->h_dest;
 308
 309         wil_swap_u16(s++, d++);
 310         wil_swap_u16(s++, d++);
 311         wil_swap_u16(s, d);
 312 }
 313
 314 /**
 315  * reap 1 frame from @swhead
 316  *
 317  * Rx descriptor copied to skb->cb
 318  *
 319  * Safe to call from IRQ
 320  */
 321 static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
 322                                          struct vring *vring)
 323 {
 324         struct device *dev = wil_to_dev(wil);
 325         struct net_device *ndev = wil_to_ndev(wil);
 326         volatile struct vring_rx_desc *d;
 327         struct vring_rx_desc *d1;
 328         struct sk_buff *skb;
 329         dma_addr_t pa;
 330         unsigned int sz = RX_BUF_LEN;
 331         u16 dmalen;
 332         u8 ftype;
 333         u8 ds_bits;
 334
 335         BUILD_BUG_ON(sizeof(struct vring_rx_desc) > sizeof(skb->cb));
 336
 337         if (wil_vring_is_empty(vring))
 338                 return NULL;
 339
 340         d = &(vring->va[vring->swhead].rx);
 341         if (!(d->dma.status & RX_DMA_STATUS_DU)) {
 342                 /* it is not error, we just reached end of Rx done area */
 343                 return NULL;
 344         }
 345
 346         pa = d->dma.addr_low | ((u64)d->dma.addr_high << 32);
 347         skb = vring->ctx[vring->swhead];
 348         dma_unmap_single(dev, pa, sz, DMA_FROM_DEVICE);
 349
 350         d1 = wil_skb_rxdesc(skb);
 351         *d1 = *d;
 352         wil_vring_advance_head(vring, 1);
 353         dmalen = le16_to_cpu(d1->dma.length);
 354         if (dmalen > sz) {
 355                 wil_err(wil, "Rx size too large: %d bytes!\n", dmalen);
 356                 kfree(skb);
 357                 return NULL;
 358         }
 359         skb_trim(skb, dmalen);
 360
 361         wil_hex_dump_txrx("Rx ", DUMP_PREFIX_OFFSET, 16, 1,
 362                           skb->data, skb_headlen(skb), false);
 363
 364
 365         wil->stats.last_mcs_rx = wil_rxdesc_mcs(d1);
 366
 367         /* use radiotap header only if required */
 368         if (ndev->type == ARPHRD_IEEE80211_RADIOTAP)
 369                 wil_rx_add_radiotap_header(wil, skb);
 370
 371         wil_dbg_txrx(wil, "Rx[%3d] : %d bytes\n", vring->swhead, d->dma.length);
 372         wil_hex_dump_txrx("Rx ", DUMP_PREFIX_NONE, 32, 4,
 373                           (const void *)d, sizeof(*d), false);
 374
 375         /* no extra checks if in sniffer mode */
 376         if (ndev->type != ARPHRD_ETHER)
 377                 return skb;
 378         /*
 379          * Non-data frames may be delivered through Rx DMA channel (ex: BAR)
 380          * Driver should recognize it by frame type, that is found
 381          * in Rx descriptor. If type is not data, it is 802.11 frame as is
 382          */
 383         ftype = wil_rxdesc_ftype(d1) << 2;
 384         if (ftype != IEEE80211_FTYPE_DATA) {
 385                 wil_dbg_txrx(wil, "Non-data frame ftype 0x%08x\n", ftype);
 386                 /* TODO: process it */
 387                 kfree_skb(skb);
 388                 return NULL;
 389         }
 390
 391         if (skb->len < ETH_HLEN) {
 392                 wil_err(wil, "Short frame, len = %d\n", skb->len);
 393                 /* TODO: process it (i.e. BAR) */
 394                 kfree_skb(skb);
 395                 return NULL;
 396         }
 397
 398         ds_bits = wil_rxdesc_ds_bits(d1);
 399         if (ds_bits == 1) {
 400                 /*
 401                  * HW bug - in ToDS mode, i.e. Rx on AP side,
 402                  * addresses get swapped
 403                  */
 404                 wil_swap_ethaddr(skb->data);
 405         }
 406
 407         return skb;
 408 }
 409
 410 /**
 411  * allocate and fill up to @count buffers in rx ring
 412  * buffers posted at @swtail
 413  */
 414 static int wil_rx_refill(struct wil6210_priv *wil, int count)
 415 {
 416         struct net_device *ndev = wil_to_ndev(wil);
 417         struct vring *v = &wil->vring_rx;
 418         u32 next_tail;
 419         int rc = 0;
 420         int headroom = ndev->type == ARPHRD_IEEE80211_RADIOTAP ?
 421                         WIL6210_RTAP_SIZE : 0;
 422
 423         for (; next_tail = wil_vring_next_tail(v),
 424                         (next_tail != v->swhead) && (count-- > 0);
 425                         v->swtail = next_tail) {
 426                 rc = wil_vring_alloc_skb(wil, v, v->swtail, headroom);
 427                 if (rc) {
 428                         wil_err(wil, "Error %d in wil_rx_refill[%d]\n",
 429                                 rc, v->swtail);
 430                         break;
 431                 }
 432         }
 433         iowrite32(v->swtail, wil->csr + HOSTADDR(v->hwtail));
 434
 435         return rc;
 436 }
 437
 438 /*
 439  * Pass Rx packet to the netif. Update statistics.
 440  */
 441 static void wil_netif_rx_any(struct sk_buff *skb, struct net_device *ndev)
 442 {
 443         int rc;
 444         unsigned int len = skb->len;
 445
 446         skb_orphan(skb);
 447
 448         if (in_interrupt())
 449                 rc = netif_rx(skb);
 450         else
 451                 rc = netif_rx_ni(skb);
 452
 453         if (likely(rc == NET_RX_SUCCESS)) {
 454                 ndev->stats.rx_packets++;
 455                 ndev->stats.rx_bytes += len;
 456
 457         } else {
 458                 ndev->stats.rx_dropped++;
 459         }
 460 }
 461
 462 /**
 463  * Proceed all completed skb's from Rx VRING
 464  *
 465  * Safe to call from IRQ
 466  */
 467 void wil_rx_handle(struct wil6210_priv *wil)
 468 {
 469         struct net_device *ndev = wil_to_ndev(wil);
 470         struct vring *v = &wil->vring_rx;
 471         struct sk_buff *skb;
 472
 473         if (!v->va) {
 474                 wil_err(wil, "Rx IRQ while Rx not yet initialized\n");
 475                 return;
 476         }
 477         wil_dbg_txrx(wil, "%s()\n", __func__);
 478         while (NULL != (skb = wil_vring_reap_rx(wil, v))) {
 479
 480                 if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 481                         skb->dev = ndev;
 482                         skb_reset_mac_header(skb);
 483                         skb->ip_summed = CHECKSUM_UNNECESSARY;
 484                         skb->pkt_type = PACKET_OTHERHOST;
 485                         skb->protocol = htons(ETH_P_802_2);
 486
 487                 } else {
 488                         skb->protocol = eth_type_trans(skb, ndev);
 489                 }
 490
 491                 wil_netif_rx_any(skb, ndev);
 492         }
 493         wil_rx_refill(wil, v->size);
 494 }
 495
 496 int wil_rx_init(struct wil6210_priv *wil)
 497 {
 498         struct vring *vring = &wil->vring_rx;
 499         int rc;
 500
 501         vring->size = WIL6210_RX_RING_SIZE;
 502         rc = wil_vring_alloc(wil, vring);
 503         if (rc)
 504                 return rc;
 505
 506         rc = wmi_rx_chain_add(wil, vring);
 507         if (rc)
 508                 goto err_free;
 509
 510         rc = wil_rx_refill(wil, vring->size);
 511         if (rc)
 512                 goto err_free;
 513
 514         return 0;
 515  err_free:
 516         wil_vring_free(wil, vring, 0);
 517
 518         return rc;
 519 }
 520
 521 void wil_rx_fini(struct wil6210_priv *wil)
 522 {
 523         struct vring *vring = &wil->vring_rx;
 524
 525         if (vring->va)
 526                 wil_vring_free(wil, vring, 0);
 527 }
 528
 529 int wil_vring_init_tx(struct wil6210_priv *wil, int id, int size,
 530                       int cid, int tid)
 531 {
 532         int rc;
 533         struct wmi_vring_cfg_cmd cmd = {
 534                 .action = cpu_to_le32(WMI_VRING_CMD_ADD),
 535                 .vring_cfg = {
 536                         .tx_sw_ring = {
 537                                 .max_mpdu_size = cpu_to_le16(TX_BUF_LEN),
 538                                 .ring_size = cpu_to_le16(size),
 539                         },
 540                         .ringid = id,
 541                         .cidxtid = (cid & 0xf) | ((tid & 0xf) << 4),
 542                         .encap_trans_type = WMI_VRING_ENC_TYPE_802_3,
 543                         .mac_ctrl = 0,
 544                         .to_resolution = 0,
 545                         .agg_max_wsize = 16,
 546                         .schd_params = {
 547                                 .priority = cpu_to_le16(0),
 548                                 .timeslot_us = cpu_to_le16(0xfff),
 549                         },
 550                 },
 551         };
 552         struct {
 553                 struct wil6210_mbox_hdr_wmi wmi;
 554                 struct wmi_vring_cfg_done_event cmd;
 555         } __packed reply;
 556         struct vring *vring = &wil->vring_tx[id];
 557
 558         if (vring->va) {
 559                 wil_err(wil, "Tx ring [%d] already allocated\n", id);
 560                 rc = -EINVAL;
 561                 goto out;
 562         }
 563
 564         vring->size = size;
 565         rc = wil_vring_alloc(wil, vring);
 566         if (rc)
 567                 goto out;
 568
 569         cmd.vring_cfg.tx_sw_ring.ring_mem_base = cpu_to_le64(vring->pa);
 570
 571         rc = wmi_call(wil, WMI_VRING_CFG_CMDID, &cmd, sizeof(cmd),
 572                       WMI_VRING_CFG_DONE_EVENTID, &reply, sizeof(reply), 100);
 573         if (rc)
 574                 goto out_free;
 575
 576         if (reply.cmd.status != WMI_FW_STATUS_SUCCESS) {
 577                 wil_err(wil, "Tx config failed, status 0x%02x\n",
 578                         reply.cmd.status);
 579                 rc = -EINVAL;
 580                 goto out_free;
 581         }
 582         vring->hwtail = le32_to_cpu(reply.cmd.tx_vring_tail_ptr);
 583
 584         return 0;
 585  out_free:
 586         wil_vring_free(wil, vring, 1);
 587  out:
 588
 589         return rc;
 590 }
 591
 592 void wil_vring_fini_tx(struct wil6210_priv *wil, int id)
 593 {
 594         struct vring *vring = &wil->vring_tx[id];
 595
 596         if (!vring->va)
 597                 return;
 598
 599         wil_vring_free(wil, vring, 1);
 600 }
 601
 602 static struct vring *wil_find_tx_vring(struct wil6210_priv *wil,
 603                                        struct sk_buff *skb)
 604 {
 605         struct vring *v = &wil->vring_tx[0];
 606
 607         if (v->va)
 608                 return v;
 609
 610         return NULL;
 611 }
 612
 613 static int wil_tx_desc_map(volatile struct vring_tx_desc *d,
 614                            dma_addr_t pa, u32 len)
 615 {
 616         d->dma.addr_low = lower_32_bits(pa);
 617         d->dma.addr_high = (u16)upper_32_bits(pa);
 618         d->dma.ip_length = 0;
 619         /* 0..6: mac_length; 7:ip_version 0-IP6 1-IP4*/
 620         d->dma.b11 = 0/*14 | BIT(7)*/;
 621         d->dma.error = 0;
 622         d->dma.status = 0; /* BIT(0) should be 0 for HW_OWNED */
 623         d->dma.length = cpu_to_le16((u16)len);
 624         d->dma.d0 = 0;
 625         d->mac.d[0] = 0;
 626         d->mac.d[1] = 0;
 627         d->mac.d[2] = 0;
 628         d->mac.ucode_cmd = 0;
 629         /* use dst index 0 */
 630         d->mac.d[1] |= BIT(MAC_CFG_DESC_TX_1_DST_INDEX_EN_POS) |
 631                        (0 << MAC_CFG_DESC_TX_1_DST_INDEX_POS);
 632         /* translation type:  0 - bypass; 1 - 802.3; 2 - native wifi */
 633         d->mac.d[2] = BIT(MAC_CFG_DESC_TX_2_SNAP_HDR_INSERTION_EN_POS) |
 634                       (1 << MAC_CFG_DESC_TX_2_L2_TRANSLATION_TYPE_POS);
 635
 636         return 0;
 637 }
 638
 639 static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
 640                         struct sk_buff *skb)
 641 {
 642         struct device *dev = wil_to_dev(wil);
 643         volatile struct vring_tx_desc *d;
 644         u32 swhead = vring->swhead;
 645         int avail = wil_vring_avail_tx(vring);
 646         int nr_frags = skb_shinfo(skb)->nr_frags;
 647         uint f;
 648         int vring_index = vring - wil->vring_tx;
 649         uint i = swhead;
 650         dma_addr_t pa;
 651
 652         wil_dbg_txrx(wil, "%s()\n", __func__);
 653
 654         if (avail < vring->size/8)
 655                 netif_tx_stop_all_queues(wil_to_ndev(wil));
 656         if (avail < 1 + nr_frags) {
 657                 wil_err(wil, "Tx ring full. No space for %d fragments\n",
 658                         1 + nr_frags);
 659                 return -ENOMEM;
 660         }
 661         d = &(vring->va[i].tx);
 662
 663         /* FIXME FW can accept only unicast frames for the peer */
 664         memcpy(skb->data, wil->dst_addr[vring_index], ETH_ALEN);
 665
 666         pa = dma_map_single(dev, skb->data,
 667                         skb_headlen(skb), DMA_TO_DEVICE);
 668
 669         wil_dbg_txrx(wil, "Tx skb %d bytes %p -> %#08llx\n", skb_headlen(skb),
 670                      skb->data, (unsigned long long)pa);
 671         wil_hex_dump_txrx("Tx ", DUMP_PREFIX_OFFSET, 16, 1,
 672                           skb->data, skb_headlen(skb), false);
 673
 674         if (unlikely(dma_mapping_error(dev, pa)))
 675                 return -EINVAL;
 676         /* 1-st segment */
 677         wil_tx_desc_map(d, pa, skb_headlen(skb));
 678         d->mac.d[2] |= ((nr_frags + 1) <<
 679                        MAC_CFG_DESC_TX_2_NUM_OF_DESCRIPTORS_POS);
 680         /* middle segments */
 681         for (f = 0; f < nr_frags; f++) {
 682                 const struct skb_frag_struct *frag =
 683                                 &skb_shinfo(skb)->frags[f];
 684                 int len = skb_frag_size(frag);
 685                 i = (swhead + f + 1) % vring->size;
 686                 d = &(vring->va[i].tx);
 687                 pa = skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag),
 688                                 DMA_TO_DEVICE);
 689                 if (unlikely(dma_mapping_error(dev, pa)))
 690                         goto dma_error;
 691                 wil_tx_desc_map(d, pa, len);
 692                 vring->ctx[i] = NULL;
 693         }
 694         /* for the last seg only */
 695         d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_EOP_POS);
 696         d->dma.d0 |= BIT(9); /* BUG: undocumented bit */
 697         d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_CMD_DMA_IT_POS);
 698         d->dma.d0 |= (vring_index << DMA_CFG_DESC_TX_0_QID_POS);
 699
 700         wil_hex_dump_txrx("Tx ", DUMP_PREFIX_NONE, 32, 4,
 701                           (const void *)d, sizeof(*d), false);
 702
 703         /* advance swhead */
 704         wil_vring_advance_head(vring, nr_frags + 1);
 705         wil_dbg_txrx(wil, "Tx swhead %d -> %d\n", swhead, vring->swhead);
 706         iowrite32(vring->swhead, wil->csr + HOSTADDR(vring->hwtail));
 707         /* hold reference to skb
 708          * to prevent skb release before accounting
 709          * in case of immediate "tx done"
 710          */
 711         vring->ctx[i] = skb_get(skb);
 712
 713         return 0;
 714  dma_error:
 715         /* unmap what we have mapped */
 716         /* Note: increment @f to operate with positive index */
 717         for (f++; f > 0; f--) {
 718                 u16 dmalen;
 719
 720                 i = (swhead + f) % vring->size;
 721                 d = &(vring->va[i].tx);
 722                 d->dma.status = TX_DMA_STATUS_DU;
 723                 pa = d->dma.addr_low | ((u64)d->dma.addr_high << 32);
 724                 dmalen = le16_to_cpu(d->dma.length);
 725                 if (vring->ctx[i])
 726                         dma_unmap_single(dev, pa, dmalen, DMA_TO_DEVICE);
 727                 else
 728                         dma_unmap_page(dev, pa, dmalen, DMA_TO_DEVICE);
 729         }
 730
 731         return -EINVAL;
 732 }
 733
 734
 735 netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 736 {
 737         struct wil6210_priv *wil = ndev_to_wil(ndev);
 738         struct vring *vring;
 739         int rc;
 740
 741         wil_dbg_txrx(wil, "%s()\n", __func__);
 742         if (!test_bit(wil_status_fwready, &wil->status)) {
 743                 wil_err(wil, "FW not ready\n");
 744                 goto drop;
 745         }
 746         if (!test_bit(wil_status_fwconnected, &wil->status)) {
 747                 wil_err(wil, "FW not connected\n");
 748                 goto drop;
 749         }
 750         if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 751                 wil_err(wil, "Xmit in monitor mode not supported\n");
 752                 goto drop;
 753         }
 754         if (skb->protocol == cpu_to_be16(ETH_P_PAE)) {
 755                 rc = wmi_tx_eapol(wil, skb);
 756         } else {
 757                 /* find vring */
 758                 vring = wil_find_tx_vring(wil, skb);
 759                 if (!vring) {
 760                         wil_err(wil, "No Tx VRING available\n");
 761                         goto drop;
 762                 }
 763                 /* set up vring entry */
 764                 rc = wil_tx_vring(wil, vring, skb);
 765         }
 766         switch (rc) {
 767         case 0:
 768                 /* statistics will be updated on the tx_complete */
 769                 dev_kfree_skb_any(skb);
 770                 return NETDEV_TX_OK;
 771         case -ENOMEM:
 772                 return NETDEV_TX_BUSY;
 773         default:
 774                 break; /* goto drop; */
 775         }
 776  drop:
 777         netif_tx_stop_all_queues(ndev);
 778         ndev->stats.tx_dropped++;
 779         dev_kfree_skb_any(skb);
 780
 781         return NET_XMIT_DROP;
 782 }
 783
 784 /**
 785  * Clean up transmitted skb's from the Tx VRING
 786  *
 787  * Safe to call from IRQ
 788  */
 789 void wil_tx_complete(struct wil6210_priv *wil, int ringid)
 790 {
 791         struct net_device *ndev = wil_to_ndev(wil);
 792         struct device *dev = wil_to_dev(wil);
 793         struct vring *vring = &wil->vring_tx[ringid];
 794
 795         if (!vring->va) {
 796                 wil_err(wil, "Tx irq[%d]: vring not initialized\n", ringid);
 797                 return;
 798         }
 799
 800         wil_dbg_txrx(wil, "%s(%d)\n", __func__, ringid);
 801
 802         while (!wil_vring_is_empty(vring)) {
 803                 volatile struct vring_tx_desc *d1 =
 804                                               &vring->va[vring->swtail].tx;
 805                 struct vring_tx_desc dd, *d = &dd;
 806                 dma_addr_t pa;
 807                 struct sk_buff *skb;
 808                 u16 dmalen;
 809
 810                 dd = *d1;
 811
 812                 if (!(d->dma.status & TX_DMA_STATUS_DU))
 813                         break;
 814
 815                 dmalen = le16_to_cpu(d->dma.length);
 816                 wil_dbg_txrx(wil,
 817                              "Tx[%3d] : %d bytes, status 0x%02x err 0x%02x\n",
 818                              vring->swtail, dmalen, d->dma.status,
 819                              d->dma.error);
 820                 wil_hex_dump_txrx("TxC ", DUMP_PREFIX_NONE, 32, 4,
 821                                   (const void *)d, sizeof(*d), false);
 822
 823                 pa = d->dma.addr_low | ((u64)d->dma.addr_high << 32);
 824                 skb = vring->ctx[vring->swtail];
 825                 if (skb) {
 826                         if (d->dma.error == 0) {
 827                                 ndev->stats.tx_packets++;
 828                                 ndev->stats.tx_bytes += skb->len;
 829                         } else {
 830                                 ndev->stats.tx_errors++;
 831                         }
 832
 833                         dma_unmap_single(dev, pa, dmalen, DMA_TO_DEVICE);
 834                         dev_kfree_skb_any(skb);
 835                         vring->ctx[vring->swtail] = NULL;
 836                 } else {
 837                         dma_unmap_page(dev, pa, dmalen, DMA_TO_DEVICE);
 838                 }
 839                 d->dma.addr_low = 0;
 840                 d->dma.addr_high = 0;
 841                 d->dma.length = 0;
 842                 d->dma.status = TX_DMA_STATUS_DU;
 843                 vring->swtail = wil_vring_next_tail(vring);
 844         }
 845         if (wil_vring_avail_tx(vring) > vring->size/4)
 846                 netif_tx_wake_all_queues(wil_to_ndev(wil));
 847 }