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