Pileus Git - ~andy/linux/blob - drivers/net/ethernet/intel/i40e/i40e_txrx.c

   1 /*******************************************************************************
   2  *
   3  * Intel Ethernet Controller XL710 Family Linux Driver
   4  * Copyright(c) 2013 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * The full GNU General Public License is included in this distribution in
  20  * the file called "COPYING".
  21  *
  22  * Contact Information:
  23  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  24  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  25  *
  26  ******************************************************************************/
  27
  28 #include "i40e.h"
  29
  30 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
  31                                 u32 td_tag)
  32 {
  33         return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
  34                            ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
  35                            ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
  36                            ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
  37                            ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
  38 }
  39
  40 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
  41 /**
  42  * i40e_program_fdir_filter - Program a Flow Director filter
  43  * @fdir_input: Packet data that will be filter parameters
  44  * @pf: The pf pointer
  45  * @add: True for add/update, False for remove
  46  **/
  47 int i40e_program_fdir_filter(struct i40e_fdir_data *fdir_data,
  48                              struct i40e_pf *pf, bool add)
  49 {
  50         struct i40e_filter_program_desc *fdir_desc;
  51         struct i40e_tx_buffer *tx_buf;
  52         struct i40e_tx_desc *tx_desc;
  53         struct i40e_ring *tx_ring;
  54         unsigned int fpt, dcc;
  55         struct i40e_vsi *vsi;
  56         struct device *dev;
  57         dma_addr_t dma;
  58         u32 td_cmd = 0;
  59         u16 i;
  60
  61         /* find existing FDIR VSI */
  62         vsi = NULL;
  63         for (i = 0; i < pf->hw.func_caps.num_vsis; i++)
  64                 if (pf->vsi[i] && pf->vsi[i]->type == I40E_VSI_FDIR)
  65                         vsi = pf->vsi[i];
  66         if (!vsi)
  67                 return -ENOENT;
  68
  69         tx_ring = vsi->tx_rings[0];
  70         dev = tx_ring->dev;
  71
  72         dma = dma_map_single(dev, fdir_data->raw_packet,
  73                              I40E_FDIR_MAX_RAW_PACKET_LOOKUP, DMA_TO_DEVICE);
  74         if (dma_mapping_error(dev, dma))
  75                 goto dma_fail;
  76
  77         /* grab the next descriptor */
  78         i = tx_ring->next_to_use;
  79         fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
  80         tx_buf = &tx_ring->tx_bi[i];
  81
  82         tx_ring->next_to_use = (i + 1 < tx_ring->count) ? i + 1 : 0;
  83
  84         fpt = (fdir_data->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
  85               I40E_TXD_FLTR_QW0_QINDEX_MASK;
  86
  87         fpt |= (fdir_data->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT) &
  88                I40E_TXD_FLTR_QW0_FLEXOFF_MASK;
  89
  90         fpt |= (fdir_data->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) &
  91                I40E_TXD_FLTR_QW0_PCTYPE_MASK;
  92
  93         /* Use LAN VSI Id if not programmed by user */
  94         if (fdir_data->dest_vsi == 0)
  95                 fpt |= (pf->vsi[pf->lan_vsi]->id) <<
  96                        I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
  97         else
  98                 fpt |= ((u32)fdir_data->dest_vsi <<
  99                         I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT) &
 100                        I40E_TXD_FLTR_QW0_DEST_VSI_MASK;
 101
 102         fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(fpt);
 103
 104         dcc = I40E_TX_DESC_DTYPE_FILTER_PROG;
 105
 106         if (add)
 107                 dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
 108                        I40E_TXD_FLTR_QW1_PCMD_SHIFT;
 109         else
 110                 dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
 111                        I40E_TXD_FLTR_QW1_PCMD_SHIFT;
 112
 113         dcc |= (fdir_data->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT) &
 114                I40E_TXD_FLTR_QW1_DEST_MASK;
 115
 116         dcc |= (fdir_data->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT) &
 117                I40E_TXD_FLTR_QW1_FD_STATUS_MASK;
 118
 119         if (fdir_data->cnt_index != 0) {
 120                 dcc |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
 121                 dcc |= ((u32)fdir_data->cnt_index <<
 122                         I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
 123                        I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
 124         }
 125
 126         fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dcc);
 127         fdir_desc->fd_id = cpu_to_le32(fdir_data->fd_id);
 128
 129         /* Now program a dummy descriptor */
 130         i = tx_ring->next_to_use;
 131         tx_desc = I40E_TX_DESC(tx_ring, i);
 132
 133         tx_ring->next_to_use = (i + 1 < tx_ring->count) ? i + 1 : 0;
 134
 135         tx_desc->buffer_addr = cpu_to_le64(dma);
 136         td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
 137
 138         tx_desc->cmd_type_offset_bsz =
 139                 build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_LOOKUP, 0);
 140
 141         /* Force memory writes to complete before letting h/w
 142          * know there are new descriptors to fetch.  (Only
 143          * applicable for weak-ordered memory model archs,
 144          * such as IA-64).
 145          */
 146         wmb();
 147
 148         /* Mark the data descriptor to be watched */
 149         tx_buf->next_to_watch = tx_desc;
 150
 151         writel(tx_ring->next_to_use, tx_ring->tail);
 152         return 0;
 153
 154 dma_fail:
 155         return -1;
 156 }
 157
 158 /**
 159  * i40e_fd_handle_status - check the Programming Status for FD
 160  * @rx_ring: the Rx ring for this descriptor
 161  * @qw: the descriptor data
 162  * @prog_id: the id originally used for programming
 163  *
 164  * This is used to verify if the FD programming or invalidation
 165  * requested by SW to the HW is successful or not and take actions accordingly.
 166  **/
 167 static void i40e_fd_handle_status(struct i40e_ring *rx_ring, u32 qw, u8 prog_id)
 168 {
 169         struct pci_dev *pdev = rx_ring->vsi->back->pdev;
 170         u32 error;
 171
 172         error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
 173                 I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
 174
 175         /* for now just print the Status */
 176         dev_info(&pdev->dev, "FD programming id %02x, Status %08x\n",
 177                  prog_id, error);
 178 }
 179
 180 /**
 181  * i40e_unmap_and_free_tx_resource - Release a Tx buffer
 182  * @ring:      the ring that owns the buffer
 183  * @tx_buffer: the buffer to free
 184  **/
 185 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
 186                                             struct i40e_tx_buffer *tx_buffer)
 187 {
 188         if (tx_buffer->skb) {
 189                 dev_kfree_skb_any(tx_buffer->skb);
 190                 if (dma_unmap_len(tx_buffer, len))
 191                         dma_unmap_single(ring->dev,
 192                                          dma_unmap_addr(tx_buffer, dma),
 193                                          dma_unmap_len(tx_buffer, len),
 194                                          DMA_TO_DEVICE);
 195         } else if (dma_unmap_len(tx_buffer, len)) {
 196                 dma_unmap_page(ring->dev,
 197                                dma_unmap_addr(tx_buffer, dma),
 198                                dma_unmap_len(tx_buffer, len),
 199                                DMA_TO_DEVICE);
 200         }
 201         tx_buffer->next_to_watch = NULL;
 202         tx_buffer->skb = NULL;
 203         dma_unmap_len_set(tx_buffer, len, 0);
 204         /* tx_buffer must be completely set up in the transmit path */
 205 }
 206
 207 /**
 208  * i40e_clean_tx_ring - Free any empty Tx buffers
 209  * @tx_ring: ring to be cleaned
 210  **/
 211 void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
 212 {
 213         unsigned long bi_size;
 214         u16 i;
 215
 216         /* ring already cleared, nothing to do */
 217         if (!tx_ring->tx_bi)
 218                 return;
 219
 220         /* Free all the Tx ring sk_buffs */
 221         for (i = 0; i < tx_ring->count; i++)
 222                 i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
 223
 224         bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
 225         memset(tx_ring->tx_bi, 0, bi_size);
 226
 227         /* Zero out the descriptor ring */
 228         memset(tx_ring->desc, 0, tx_ring->size);
 229
 230         tx_ring->next_to_use = 0;
 231         tx_ring->next_to_clean = 0;
 232
 233         if (!tx_ring->netdev)
 234                 return;
 235
 236         /* cleanup Tx queue statistics */
 237         netdev_tx_reset_queue(netdev_get_tx_queue(tx_ring->netdev,
 238                                                   tx_ring->queue_index));
 239 }
 240
 241 /**
 242  * i40e_free_tx_resources - Free Tx resources per queue
 243  * @tx_ring: Tx descriptor ring for a specific queue
 244  *
 245  * Free all transmit software resources
 246  **/
 247 void i40e_free_tx_resources(struct i40e_ring *tx_ring)
 248 {
 249         i40e_clean_tx_ring(tx_ring);
 250         kfree(tx_ring->tx_bi);
 251         tx_ring->tx_bi = NULL;
 252
 253         if (tx_ring->desc) {
 254                 dma_free_coherent(tx_ring->dev, tx_ring->size,
 255                                   tx_ring->desc, tx_ring->dma);
 256                 tx_ring->desc = NULL;
 257         }
 258 }
 259
 260 /**
 261  * i40e_get_tx_pending - how many tx descriptors not processed
 262  * @tx_ring: the ring of descriptors
 263  *
 264  * Since there is no access to the ring head register
 265  * in XL710, we need to use our local copies
 266  **/
 267 static u32 i40e_get_tx_pending(struct i40e_ring *ring)
 268 {
 269         u32 ntu = ((ring->next_to_clean <= ring->next_to_use)
 270                         ? ring->next_to_use
 271                         : ring->next_to_use + ring->count);
 272         return ntu - ring->next_to_clean;
 273 }
 274
 275 /**
 276  * i40e_check_tx_hang - Is there a hang in the Tx queue
 277  * @tx_ring: the ring of descriptors
 278  **/
 279 static bool i40e_check_tx_hang(struct i40e_ring *tx_ring)
 280 {
 281         u32 tx_pending = i40e_get_tx_pending(tx_ring);
 282         bool ret = false;
 283
 284         clear_check_for_tx_hang(tx_ring);
 285
 286         /* Check for a hung queue, but be thorough. This verifies
 287          * that a transmit has been completed since the previous
 288          * check AND there is at least one packet pending. The
 289          * ARMED bit is set to indicate a potential hang. The
 290          * bit is cleared if a pause frame is received to remove
 291          * false hang detection due to PFC or 802.3x frames. By
 292          * requiring this to fail twice we avoid races with
 293          * PFC clearing the ARMED bit and conditions where we
 294          * run the check_tx_hang logic with a transmit completion
 295          * pending but without time to complete it yet.
 296          */
 297         if ((tx_ring->tx_stats.tx_done_old == tx_ring->stats.packets) &&
 298             tx_pending) {
 299                 /* make sure it is true for two checks in a row */
 300                 ret = test_and_set_bit(__I40E_HANG_CHECK_ARMED,
 301                                        &tx_ring->state);
 302         } else {
 303                 /* update completed stats and disarm the hang check */
 304                 tx_ring->tx_stats.tx_done_old = tx_ring->stats.packets;
 305                 clear_bit(__I40E_HANG_CHECK_ARMED, &tx_ring->state);
 306         }
 307
 308         return ret;
 309 }
 310
 311 /**
 312  * i40e_clean_tx_irq - Reclaim resources after transmit completes
 313  * @tx_ring:  tx ring to clean
 314  * @budget:   how many cleans we're allowed
 315  *
 316  * Returns true if there's any budget left (e.g. the clean is finished)
 317  **/
 318 static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
 319 {
 320         u16 i = tx_ring->next_to_clean;
 321         struct i40e_tx_buffer *tx_buf;
 322         struct i40e_tx_desc *tx_desc;
 323         unsigned int total_packets = 0;
 324         unsigned int total_bytes = 0;
 325
 326         tx_buf = &tx_ring->tx_bi[i];
 327         tx_desc = I40E_TX_DESC(tx_ring, i);
 328         i -= tx_ring->count;
 329
 330         do {
 331                 struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
 332
 333                 /* if next_to_watch is not set then there is no work pending */
 334                 if (!eop_desc)
 335                         break;
 336
 337                 /* prevent any other reads prior to eop_desc */
 338                 read_barrier_depends();
 339
 340                 /* if the descriptor isn't done, no work yet to do */
 341                 if (!(eop_desc->cmd_type_offset_bsz &
 342                       cpu_to_le64(I40E_TX_DESC_DTYPE_DESC_DONE)))
 343                         break;
 344
 345                 /* clear next_to_watch to prevent false hangs */
 346                 tx_buf->next_to_watch = NULL;
 347
 348                 /* update the statistics for this packet */
 349                 total_bytes += tx_buf->bytecount;
 350                 total_packets += tx_buf->gso_segs;
 351
 352                 /* free the skb */
 353                 dev_kfree_skb_any(tx_buf->skb);
 354
 355                 /* unmap skb header data */
 356                 dma_unmap_single(tx_ring->dev,
 357                                  dma_unmap_addr(tx_buf, dma),
 358                                  dma_unmap_len(tx_buf, len),
 359                                  DMA_TO_DEVICE);
 360
 361                 /* clear tx_buffer data */
 362                 tx_buf->skb = NULL;
 363                 dma_unmap_len_set(tx_buf, len, 0);
 364
 365                 /* unmap remaining buffers */
 366                 while (tx_desc != eop_desc) {
 367
 368                         tx_buf++;
 369                         tx_desc++;
 370                         i++;
 371                         if (unlikely(!i)) {
 372                                 i -= tx_ring->count;
 373                                 tx_buf = tx_ring->tx_bi;
 374                                 tx_desc = I40E_TX_DESC(tx_ring, 0);
 375                         }
 376
 377                         /* unmap any remaining paged data */
 378                         if (dma_unmap_len(tx_buf, len)) {
 379                                 dma_unmap_page(tx_ring->dev,
 380                                                dma_unmap_addr(tx_buf, dma),
 381                                                dma_unmap_len(tx_buf, len),
 382                                                DMA_TO_DEVICE);
 383                                 dma_unmap_len_set(tx_buf, len, 0);
 384                         }
 385                 }
 386
 387                 /* move us one more past the eop_desc for start of next pkt */
 388                 tx_buf++;
 389                 tx_desc++;
 390                 i++;
 391                 if (unlikely(!i)) {
 392                         i -= tx_ring->count;
 393                         tx_buf = tx_ring->tx_bi;
 394                         tx_desc = I40E_TX_DESC(tx_ring, 0);
 395                 }
 396
 397                 /* update budget accounting */
 398                 budget--;
 399         } while (likely(budget));
 400
 401         i += tx_ring->count;
 402         tx_ring->next_to_clean = i;
 403         u64_stats_update_begin(&tx_ring->syncp);
 404         tx_ring->stats.bytes += total_bytes;
 405         tx_ring->stats.packets += total_packets;
 406         u64_stats_update_end(&tx_ring->syncp);
 407         tx_ring->q_vector->tx.total_bytes += total_bytes;
 408         tx_ring->q_vector->tx.total_packets += total_packets;
 409
 410         if (check_for_tx_hang(tx_ring) && i40e_check_tx_hang(tx_ring)) {
 411                 /* schedule immediate reset if we believe we hung */
 412                 dev_info(tx_ring->dev, "Detected Tx Unit Hang\n"
 413                          "  VSI                  <%d>\n"
 414                          "  Tx Queue             <%d>\n"
 415                          "  next_to_use          <%x>\n"
 416                          "  next_to_clean        <%x>\n",
 417                          tx_ring->vsi->seid,
 418                          tx_ring->queue_index,
 419                          tx_ring->next_to_use, i);
 420                 dev_info(tx_ring->dev, "tx_bi[next_to_clean]\n"
 421                          "  time_stamp           <%lx>\n"
 422                          "  jiffies              <%lx>\n",
 423                          tx_ring->tx_bi[i].time_stamp, jiffies);
 424
 425                 netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
 426
 427                 dev_info(tx_ring->dev,
 428                          "tx hang detected on queue %d, resetting adapter\n",
 429                          tx_ring->queue_index);
 430
 431                 tx_ring->netdev->netdev_ops->ndo_tx_timeout(tx_ring->netdev);
 432
 433                 /* the adapter is about to reset, no point in enabling stuff */
 434                 return true;
 435         }
 436
 437         netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev,
 438                                                       tx_ring->queue_index),
 439                                   total_packets, total_bytes);
 440
 441 #define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
 442         if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
 443                      (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
 444                 /* Make sure that anybody stopping the queue after this
 445                  * sees the new next_to_clean.
 446                  */
 447                 smp_mb();
 448                 if (__netif_subqueue_stopped(tx_ring->netdev,
 449                                              tx_ring->queue_index) &&
 450                    !test_bit(__I40E_DOWN, &tx_ring->vsi->state)) {
 451                         netif_wake_subqueue(tx_ring->netdev,
 452                                             tx_ring->queue_index);
 453                         ++tx_ring->tx_stats.restart_queue;
 454                 }
 455         }
 456
 457         return budget > 0;
 458 }
 459
 460 /**
 461  * i40e_set_new_dynamic_itr - Find new ITR level
 462  * @rc: structure containing ring performance data
 463  *
 464  * Stores a new ITR value based on packets and byte counts during
 465  * the last interrupt.  The advantage of per interrupt computation
 466  * is faster updates and more accurate ITR for the current traffic
 467  * pattern.  Constants in this function were computed based on
 468  * theoretical maximum wire speed and thresholds were set based on
 469  * testing data as well as attempting to minimize response time
 470  * while increasing bulk throughput.
 471  **/
 472 static void i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
 473 {
 474         enum i40e_latency_range new_latency_range = rc->latency_range;
 475         u32 new_itr = rc->itr;
 476         int bytes_per_int;
 477
 478         if (rc->total_packets == 0 || !rc->itr)
 479                 return;
 480
 481         /* simple throttlerate management
 482          *   0-10MB/s   lowest (100000 ints/s)
 483          *  10-20MB/s   low    (20000 ints/s)
 484          *  20-1249MB/s bulk   (8000 ints/s)
 485          */
 486         bytes_per_int = rc->total_bytes / rc->itr;
 487         switch (rc->itr) {
 488         case I40E_LOWEST_LATENCY:
 489                 if (bytes_per_int > 10)
 490                         new_latency_range = I40E_LOW_LATENCY;
 491                 break;
 492         case I40E_LOW_LATENCY:
 493                 if (bytes_per_int > 20)
 494                         new_latency_range = I40E_BULK_LATENCY;
 495                 else if (bytes_per_int <= 10)
 496                         new_latency_range = I40E_LOWEST_LATENCY;
 497                 break;
 498         case I40E_BULK_LATENCY:
 499                 if (bytes_per_int <= 20)
 500                         rc->latency_range = I40E_LOW_LATENCY;
 501                 break;
 502         }
 503
 504         switch (new_latency_range) {
 505         case I40E_LOWEST_LATENCY:
 506                 new_itr = I40E_ITR_100K;
 507                 break;
 508         case I40E_LOW_LATENCY:
 509                 new_itr = I40E_ITR_20K;
 510                 break;
 511         case I40E_BULK_LATENCY:
 512                 new_itr = I40E_ITR_8K;
 513                 break;
 514         default:
 515                 break;
 516         }
 517
 518         if (new_itr != rc->itr) {
 519                 /* do an exponential smoothing */
 520                 new_itr = (10 * new_itr * rc->itr) /
 521                           ((9 * new_itr) + rc->itr);
 522                 rc->itr = new_itr & I40E_MAX_ITR;
 523         }
 524
 525         rc->total_bytes = 0;
 526         rc->total_packets = 0;
 527 }
 528
 529 /**
 530  * i40e_update_dynamic_itr - Adjust ITR based on bytes per int
 531  * @q_vector: the vector to adjust
 532  **/
 533 static void i40e_update_dynamic_itr(struct i40e_q_vector *q_vector)
 534 {
 535         u16 vector = q_vector->vsi->base_vector + q_vector->v_idx;
 536         struct i40e_hw *hw = &q_vector->vsi->back->hw;
 537         u32 reg_addr;
 538         u16 old_itr;
 539
 540         reg_addr = I40E_PFINT_ITRN(I40E_RX_ITR, vector - 1);
 541         old_itr = q_vector->rx.itr;
 542         i40e_set_new_dynamic_itr(&q_vector->rx);
 543         if (old_itr != q_vector->rx.itr)
 544                 wr32(hw, reg_addr, q_vector->rx.itr);
 545
 546         reg_addr = I40E_PFINT_ITRN(I40E_TX_ITR, vector - 1);
 547         old_itr = q_vector->tx.itr;
 548         i40e_set_new_dynamic_itr(&q_vector->tx);
 549         if (old_itr != q_vector->tx.itr)
 550                 wr32(hw, reg_addr, q_vector->tx.itr);
 551 }
 552
 553 /**
 554  * i40e_clean_programming_status - clean the programming status descriptor
 555  * @rx_ring: the rx ring that has this descriptor
 556  * @rx_desc: the rx descriptor written back by HW
 557  *
 558  * Flow director should handle FD_FILTER_STATUS to check its filter programming
 559  * status being successful or not and take actions accordingly. FCoE should
 560  * handle its context/filter programming/invalidation status and take actions.
 561  *
 562  **/
 563 static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
 564                                           union i40e_rx_desc *rx_desc)
 565 {
 566         u64 qw;
 567         u8 id;
 568
 569         qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
 570         id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
 571                   I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
 572
 573         if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
 574                 i40e_fd_handle_status(rx_ring, qw, id);
 575 }
 576
 577 /**
 578  * i40e_setup_tx_descriptors - Allocate the Tx descriptors
 579  * @tx_ring: the tx ring to set up
 580  *
 581  * Return 0 on success, negative on error
 582  **/
 583 int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
 584 {
 585         struct device *dev = tx_ring->dev;
 586         int bi_size;
 587
 588         if (!dev)
 589                 return -ENOMEM;
 590
 591         bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
 592         tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
 593         if (!tx_ring->tx_bi)
 594                 goto err;
 595
 596         /* round up to nearest 4K */
 597         tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
 598         tx_ring->size = ALIGN(tx_ring->size, 4096);
 599         tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
 600                                            &tx_ring->dma, GFP_KERNEL);
 601         if (!tx_ring->desc) {
 602                 dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
 603                          tx_ring->size);
 604                 goto err;
 605         }
 606
 607         tx_ring->next_to_use = 0;
 608         tx_ring->next_to_clean = 0;
 609         return 0;
 610
 611 err:
 612         kfree(tx_ring->tx_bi);
 613         tx_ring->tx_bi = NULL;
 614         return -ENOMEM;
 615 }
 616
 617 /**
 618  * i40e_clean_rx_ring - Free Rx buffers
 619  * @rx_ring: ring to be cleaned
 620  **/
 621 void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
 622 {
 623         struct device *dev = rx_ring->dev;
 624         struct i40e_rx_buffer *rx_bi;
 625         unsigned long bi_size;
 626         u16 i;
 627
 628         /* ring already cleared, nothing to do */
 629         if (!rx_ring->rx_bi)
 630                 return;
 631
 632         /* Free all the Rx ring sk_buffs */
 633         for (i = 0; i < rx_ring->count; i++) {
 634                 rx_bi = &rx_ring->rx_bi[i];
 635                 if (rx_bi->dma) {
 636                         dma_unmap_single(dev,
 637                                          rx_bi->dma,
 638                                          rx_ring->rx_buf_len,
 639                                          DMA_FROM_DEVICE);
 640                         rx_bi->dma = 0;
 641                 }
 642                 if (rx_bi->skb) {
 643                         dev_kfree_skb(rx_bi->skb);
 644                         rx_bi->skb = NULL;
 645                 }
 646                 if (rx_bi->page) {
 647                         if (rx_bi->page_dma) {
 648                                 dma_unmap_page(dev,
 649                                                rx_bi->page_dma,
 650                                                PAGE_SIZE / 2,
 651                                                DMA_FROM_DEVICE);
 652                                 rx_bi->page_dma = 0;
 653                         }
 654                         __free_page(rx_bi->page);
 655                         rx_bi->page = NULL;
 656                         rx_bi->page_offset = 0;
 657                 }
 658         }
 659
 660         bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
 661         memset(rx_ring->rx_bi, 0, bi_size);
 662
 663         /* Zero out the descriptor ring */
 664         memset(rx_ring->desc, 0, rx_ring->size);
 665
 666         rx_ring->next_to_clean = 0;
 667         rx_ring->next_to_use = 0;
 668 }
 669
 670 /**
 671  * i40e_free_rx_resources - Free Rx resources
 672  * @rx_ring: ring to clean the resources from
 673  *
 674  * Free all receive software resources
 675  **/
 676 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
 677 {
 678         i40e_clean_rx_ring(rx_ring);
 679         kfree(rx_ring->rx_bi);
 680         rx_ring->rx_bi = NULL;
 681
 682         if (rx_ring->desc) {
 683                 dma_free_coherent(rx_ring->dev, rx_ring->size,
 684                                   rx_ring->desc, rx_ring->dma);
 685                 rx_ring->desc = NULL;
 686         }
 687 }
 688
 689 /**
 690  * i40e_setup_rx_descriptors - Allocate Rx descriptors
 691  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
 692  *
 693  * Returns 0 on success, negative on failure
 694  **/
 695 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
 696 {
 697         struct device *dev = rx_ring->dev;
 698         int bi_size;
 699
 700         bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
 701         rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
 702         if (!rx_ring->rx_bi)
 703                 goto err;
 704
 705         /* Round up to nearest 4K */
 706         rx_ring->size = ring_is_16byte_desc_enabled(rx_ring)
 707                 ? rx_ring->count * sizeof(union i40e_16byte_rx_desc)
 708                 : rx_ring->count * sizeof(union i40e_32byte_rx_desc);
 709         rx_ring->size = ALIGN(rx_ring->size, 4096);
 710         rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
 711                                            &rx_ring->dma, GFP_KERNEL);
 712
 713         if (!rx_ring->desc) {
 714                 dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
 715                          rx_ring->size);
 716                 goto err;
 717         }
 718
 719         rx_ring->next_to_clean = 0;
 720         rx_ring->next_to_use = 0;
 721
 722         return 0;
 723 err:
 724         kfree(rx_ring->rx_bi);
 725         rx_ring->rx_bi = NULL;
 726         return -ENOMEM;
 727 }
 728
 729 /**
 730  * i40e_release_rx_desc - Store the new tail and head values
 731  * @rx_ring: ring to bump
 732  * @val: new head index
 733  **/
 734 static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
 735 {
 736         rx_ring->next_to_use = val;
 737         /* Force memory writes to complete before letting h/w
 738          * know there are new descriptors to fetch.  (Only
 739          * applicable for weak-ordered memory model archs,
 740          * such as IA-64).
 741          */
 742         wmb();
 743         writel(val, rx_ring->tail);
 744 }
 745
 746 /**
 747  * i40e_alloc_rx_buffers - Replace used receive buffers; packet split
 748  * @rx_ring: ring to place buffers on
 749  * @cleaned_count: number of buffers to replace
 750  **/
 751 void i40e_alloc_rx_buffers(struct i40e_ring *rx_ring, u16 cleaned_count)
 752 {
 753         u16 i = rx_ring->next_to_use;
 754         union i40e_rx_desc *rx_desc;
 755         struct i40e_rx_buffer *bi;
 756         struct sk_buff *skb;
 757
 758         /* do nothing if no valid netdev defined */
 759         if (!rx_ring->netdev || !cleaned_count)
 760                 return;
 761
 762         while (cleaned_count--) {
 763                 rx_desc = I40E_RX_DESC(rx_ring, i);
 764                 bi = &rx_ring->rx_bi[i];
 765                 skb = bi->skb;
 766
 767                 if (!skb) {
 768                         skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
 769                                                         rx_ring->rx_buf_len);
 770                         if (!skb) {
 771                                 rx_ring->rx_stats.alloc_rx_buff_failed++;
 772                                 goto no_buffers;
 773                         }
 774                         /* initialize queue mapping */
 775                         skb_record_rx_queue(skb, rx_ring->queue_index);
 776                         bi->skb = skb;
 777                 }
 778
 779                 if (!bi->dma) {
 780                         bi->dma = dma_map_single(rx_ring->dev,
 781                                                  skb->data,
 782                                                  rx_ring->rx_buf_len,
 783                                                  DMA_FROM_DEVICE);
 784                         if (dma_mapping_error(rx_ring->dev, bi->dma)) {
 785                                 rx_ring->rx_stats.alloc_rx_buff_failed++;
 786                                 bi->dma = 0;
 787                                 goto no_buffers;
 788                         }
 789                 }
 790
 791                 if (ring_is_ps_enabled(rx_ring)) {
 792                         if (!bi->page) {
 793                                 bi->page = alloc_page(GFP_ATOMIC);
 794                                 if (!bi->page) {
 795                                         rx_ring->rx_stats.alloc_rx_page_failed++;
 796                                         goto no_buffers;
 797                                 }
 798                         }
 799
 800                         if (!bi->page_dma) {
 801                                 /* use a half page if we're re-using */
 802                                 bi->page_offset ^= PAGE_SIZE / 2;
 803                                 bi->page_dma = dma_map_page(rx_ring->dev,
 804                                                             bi->page,
 805                                                             bi->page_offset,
 806                                                             PAGE_SIZE / 2,
 807                                                             DMA_FROM_DEVICE);
 808                                 if (dma_mapping_error(rx_ring->dev,
 809                                                       bi->page_dma)) {
 810                                         rx_ring->rx_stats.alloc_rx_page_failed++;
 811                                         bi->page_dma = 0;
 812                                         goto no_buffers;
 813                                 }
 814                         }
 815
 816                         /* Refresh the desc even if buffer_addrs didn't change
 817                          * because each write-back erases this info.
 818                          */
 819                         rx_desc->read.pkt_addr = cpu_to_le64(bi->page_dma);
 820                         rx_desc->read.hdr_addr = cpu_to_le64(bi->dma);
 821                 } else {
 822                         rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
 823                         rx_desc->read.hdr_addr = 0;
 824                 }
 825                 i++;
 826                 if (i == rx_ring->count)
 827                         i = 0;
 828         }
 829
 830 no_buffers:
 831         if (rx_ring->next_to_use != i)
 832                 i40e_release_rx_desc(rx_ring, i);
 833 }
 834
 835 /**
 836  * i40e_receive_skb - Send a completed packet up the stack
 837  * @rx_ring:  rx ring in play
 838  * @skb: packet to send up
 839  * @vlan_tag: vlan tag for packet
 840  **/
 841 static void i40e_receive_skb(struct i40e_ring *rx_ring,
 842                              struct sk_buff *skb, u16 vlan_tag)
 843 {
 844         struct i40e_q_vector *q_vector = rx_ring->q_vector;
 845         struct i40e_vsi *vsi = rx_ring->vsi;
 846         u64 flags = vsi->back->flags;
 847
 848         if (vlan_tag & VLAN_VID_MASK)
 849                 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
 850
 851         if (flags & I40E_FLAG_IN_NETPOLL)
 852                 netif_rx(skb);
 853         else
 854                 napi_gro_receive(&q_vector->napi, skb);
 855 }
 856
 857 /**
 858  * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
 859  * @vsi: the VSI we care about
 860  * @skb: skb currently being received and modified
 861  * @rx_status: status value of last descriptor in packet
 862  * @rx_error: error value of last descriptor in packet
 863  **/
 864 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
 865                                     struct sk_buff *skb,
 866                                     u32 rx_status,
 867                                     u32 rx_error)
 868 {
 869         skb->ip_summed = CHECKSUM_NONE;
 870
 871         /* Rx csum enabled and ip headers found? */
 872         if (!(vsi->netdev->features & NETIF_F_RXCSUM &&
 873               rx_status & (1 << I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
 874                 return;
 875
 876         /* IP or L4 checksum error */
 877         if (rx_error & ((1 << I40E_RX_DESC_ERROR_IPE_SHIFT) |
 878                         (1 << I40E_RX_DESC_ERROR_L4E_SHIFT))) {
 879                 vsi->back->hw_csum_rx_error++;
 880                 return;
 881         }
 882
 883         skb->ip_summed = CHECKSUM_UNNECESSARY;
 884 }
 885
 886 /**
 887  * i40e_rx_hash - returns the hash value from the Rx descriptor
 888  * @ring: descriptor ring
 889  * @rx_desc: specific descriptor
 890  **/
 891 static inline u32 i40e_rx_hash(struct i40e_ring *ring,
 892                                union i40e_rx_desc *rx_desc)
 893 {
 894         const __le64 rss_mask =
 895                 cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
 896                             I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
 897
 898         if ((ring->netdev->features & NETIF_F_RXHASH) &&
 899             (rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask)
 900                 return le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
 901         else
 902                 return 0;
 903 }
 904
 905 /**
 906  * i40e_clean_rx_irq - Reclaim resources after receive completes
 907  * @rx_ring:  rx ring to clean
 908  * @budget:   how many cleans we're allowed
 909  *
 910  * Returns true if there's any budget left (e.g. the clean is finished)
 911  **/
 912 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 913 {
 914         unsigned int total_rx_bytes = 0, total_rx_packets = 0;
 915         u16 rx_packet_len, rx_header_len, rx_sph, rx_hbo;
 916         u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
 917         const int current_node = numa_node_id();
 918         struct i40e_vsi *vsi = rx_ring->vsi;
 919         u16 i = rx_ring->next_to_clean;
 920         union i40e_rx_desc *rx_desc;
 921         u32 rx_error, rx_status;
 922         u64 qword;
 923
 924         rx_desc = I40E_RX_DESC(rx_ring, i);
 925         qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
 926         rx_status = (qword & I40E_RXD_QW1_STATUS_MASK)
 927                                 >> I40E_RXD_QW1_STATUS_SHIFT;
 928
 929         while (rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)) {
 930                 union i40e_rx_desc *next_rxd;
 931                 struct i40e_rx_buffer *rx_bi;
 932                 struct sk_buff *skb;
 933                 u16 vlan_tag;
 934                 if (i40e_rx_is_programming_status(qword)) {
 935                         i40e_clean_programming_status(rx_ring, rx_desc);
 936                         I40E_RX_NEXT_DESC_PREFETCH(rx_ring, i, next_rxd);
 937                         goto next_desc;
 938                 }
 939                 rx_bi = &rx_ring->rx_bi[i];
 940                 skb = rx_bi->skb;
 941                 prefetch(skb->data);
 942
 943                 rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK)
 944                                               >> I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
 945                 rx_header_len = (qword & I40E_RXD_QW1_LENGTH_HBUF_MASK)
 946                                               >> I40E_RXD_QW1_LENGTH_HBUF_SHIFT;
 947                 rx_sph = (qword & I40E_RXD_QW1_LENGTH_SPH_MASK)
 948                                               >> I40E_RXD_QW1_LENGTH_SPH_SHIFT;
 949
 950                 rx_error = (qword & I40E_RXD_QW1_ERROR_MASK)
 951                                               >> I40E_RXD_QW1_ERROR_SHIFT;
 952                 rx_hbo = rx_error & (1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
 953                 rx_error &= ~(1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
 954
 955                 rx_bi->skb = NULL;
 956
 957                 /* This memory barrier is needed to keep us from reading
 958                  * any other fields out of the rx_desc until we know the
 959                  * STATUS_DD bit is set
 960                  */
 961                 rmb();
 962
 963                 /* Get the header and possibly the whole packet
 964                  * If this is an skb from previous receive dma will be 0
 965                  */
 966                 if (rx_bi->dma) {
 967                         u16 len;
 968
 969                         if (rx_hbo)
 970                                 len = I40E_RX_HDR_SIZE;
 971                         else if (rx_sph)
 972                                 len = rx_header_len;
 973                         else if (rx_packet_len)
 974                                 len = rx_packet_len;   /* 1buf/no split found */
 975                         else
 976                                 len = rx_header_len;   /* split always mode */
 977
 978                         skb_put(skb, len);
 979                         dma_unmap_single(rx_ring->dev,
 980                                          rx_bi->dma,
 981                                          rx_ring->rx_buf_len,
 982                                          DMA_FROM_DEVICE);
 983                         rx_bi->dma = 0;
 984                 }
 985
 986                 /* Get the rest of the data if this was a header split */
 987                 if (ring_is_ps_enabled(rx_ring) && rx_packet_len) {
 988
 989                         skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
 990                                            rx_bi->page,
 991                                            rx_bi->page_offset,
 992                                            rx_packet_len);
 993
 994                         skb->len += rx_packet_len;
 995                         skb->data_len += rx_packet_len;
 996                         skb->truesize += rx_packet_len;
 997
 998                         if ((page_count(rx_bi->page) == 1) &&
 999                             (page_to_nid(rx_bi->page) == current_node))
1000                                 get_page(rx_bi->page);
1001                         else
1002                                 rx_bi->page = NULL;
1003
1004                         dma_unmap_page(rx_ring->dev,
1005                                        rx_bi->page_dma,
1006                                        PAGE_SIZE / 2,
1007                                        DMA_FROM_DEVICE);
1008                         rx_bi->page_dma = 0;
1009                 }
1010                 I40E_RX_NEXT_DESC_PREFETCH(rx_ring, i, next_rxd);
1011
1012                 if (unlikely(
1013                     !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
1014                         struct i40e_rx_buffer *next_buffer;
1015
1016                         next_buffer = &rx_ring->rx_bi[i];
1017
1018                         if (ring_is_ps_enabled(rx_ring)) {
1019                                 rx_bi->skb = next_buffer->skb;
1020                                 rx_bi->dma = next_buffer->dma;
1021                                 next_buffer->skb = skb;
1022                                 next_buffer->dma = 0;
1023                         }
1024                         rx_ring->rx_stats.non_eop_descs++;
1025                         goto next_desc;
1026                 }
1027
1028                 /* ERR_MASK will only have valid bits if EOP set */
1029                 if (unlikely(rx_error & (1 << I40E_RX_DESC_ERROR_RXE_SHIFT))) {
1030                         dev_kfree_skb_any(skb);
1031                         goto next_desc;
1032                 }
1033
1034                 skb->rxhash = i40e_rx_hash(rx_ring, rx_desc);
1035                 i40e_rx_checksum(vsi, skb, rx_status, rx_error);
1036
1037                 /* probably a little skewed due to removing CRC */
1038                 total_rx_bytes += skb->len;
1039                 total_rx_packets++;
1040
1041                 skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1042                 vlan_tag = rx_status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
1043                          ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
1044                          : 0;
1045                 i40e_receive_skb(rx_ring, skb, vlan_tag);
1046
1047                 rx_ring->netdev->last_rx = jiffies;
1048                 budget--;
1049 next_desc:
1050                 rx_desc->wb.qword1.status_error_len = 0;
1051                 if (!budget)
1052                         break;
1053
1054                 cleaned_count++;
1055                 /* return some buffers to hardware, one at a time is too slow */
1056                 if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
1057                         i40e_alloc_rx_buffers(rx_ring, cleaned_count);
1058                         cleaned_count = 0;
1059                 }
1060
1061                 /* use prefetched values */
1062                 rx_desc = next_rxd;
1063                 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1064                 rx_status = (qword & I40E_RXD_QW1_STATUS_MASK)
1065                                                 >> I40E_RXD_QW1_STATUS_SHIFT;
1066         }
1067
1068         rx_ring->next_to_clean = i;
1069         u64_stats_update_begin(&rx_ring->syncp);
1070         rx_ring->stats.packets += total_rx_packets;
1071         rx_ring->stats.bytes += total_rx_bytes;
1072         u64_stats_update_end(&rx_ring->syncp);
1073         rx_ring->q_vector->rx.total_packets += total_rx_packets;
1074         rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
1075
1076         if (cleaned_count)
1077                 i40e_alloc_rx_buffers(rx_ring, cleaned_count);
1078
1079         return budget > 0;
1080 }
1081
1082 /**
1083  * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
1084  * @napi: napi struct with our devices info in it
1085  * @budget: amount of work driver is allowed to do this pass, in packets
1086  *
1087  * This function will clean all queues associated with a q_vector.
1088  *
1089  * Returns the amount of work done
1090  **/
1091 int i40e_napi_poll(struct napi_struct *napi, int budget)
1092 {
1093         struct i40e_q_vector *q_vector =
1094                                container_of(napi, struct i40e_q_vector, napi);
1095         struct i40e_vsi *vsi = q_vector->vsi;
1096         struct i40e_ring *ring;
1097         bool clean_complete = true;
1098         int budget_per_ring;
1099
1100         if (test_bit(__I40E_DOWN, &vsi->state)) {
1101                 napi_complete(napi);
1102                 return 0;
1103         }
1104
1105         /* Since the actual Tx work is minimal, we can give the Tx a larger
1106          * budget and be more aggressive about cleaning up the Tx descriptors.
1107          */
1108         i40e_for_each_ring(ring, q_vector->tx)
1109                 clean_complete &= i40e_clean_tx_irq(ring, vsi->work_limit);
1110
1111         /* We attempt to distribute budget to each Rx queue fairly, but don't
1112          * allow the budget to go below 1 because that would exit polling early.
1113          */
1114         budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
1115
1116         i40e_for_each_ring(ring, q_vector->rx)
1117                 clean_complete &= i40e_clean_rx_irq(ring, budget_per_ring);
1118
1119         /* If work not completed, return budget and polling will return */
1120         if (!clean_complete)
1121                 return budget;
1122
1123         /* Work is done so exit the polling mode and re-enable the interrupt */
1124         napi_complete(napi);
1125         if (ITR_IS_DYNAMIC(vsi->rx_itr_setting) ||
1126             ITR_IS_DYNAMIC(vsi->tx_itr_setting))
1127                 i40e_update_dynamic_itr(q_vector);
1128
1129         if (!test_bit(__I40E_DOWN, &vsi->state)) {
1130                 if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
1131                         i40e_irq_dynamic_enable(vsi,
1132                                         q_vector->v_idx + vsi->base_vector);
1133                 } else {
1134                         struct i40e_hw *hw = &vsi->back->hw;
1135                         /* We re-enable the queue 0 cause, but
1136                          * don't worry about dynamic_enable
1137                          * because we left it on for the other
1138                          * possible interrupts during napi
1139                          */
1140                         u32 qval = rd32(hw, I40E_QINT_RQCTL(0));
1141                         qval |= I40E_QINT_RQCTL_CAUSE_ENA_MASK;
1142                         wr32(hw, I40E_QINT_RQCTL(0), qval);
1143
1144                         qval = rd32(hw, I40E_QINT_TQCTL(0));
1145                         qval |= I40E_QINT_TQCTL_CAUSE_ENA_MASK;
1146                         wr32(hw, I40E_QINT_TQCTL(0), qval);
1147
1148                         i40e_irq_dynamic_enable_icr0(vsi->back);
1149                 }
1150         }
1151
1152         return 0;
1153 }
1154
1155 /**
1156  * i40e_atr - Add a Flow Director ATR filter
1157  * @tx_ring:  ring to add programming descriptor to
1158  * @skb:      send buffer
1159  * @flags:    send flags
1160  * @protocol: wire protocol
1161  **/
1162 static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
1163                      u32 flags, __be16 protocol)
1164 {
1165         struct i40e_filter_program_desc *fdir_desc;
1166         struct i40e_pf *pf = tx_ring->vsi->back;
1167         union {
1168                 unsigned char *network;
1169                 struct iphdr *ipv4;
1170                 struct ipv6hdr *ipv6;
1171         } hdr;
1172         struct tcphdr *th;
1173         unsigned int hlen;
1174         u32 flex_ptype, dtype_cmd;
1175         u16 i;
1176
1177         /* make sure ATR is enabled */
1178         if (!(pf->flags & I40E_FLAG_FDIR_ATR_ENABLED))
1179                 return;
1180
1181         /* if sampling is disabled do nothing */
1182         if (!tx_ring->atr_sample_rate)
1183                 return;
1184
1185         tx_ring->atr_count++;
1186
1187         /* snag network header to get L4 type and address */
1188         hdr.network = skb_network_header(skb);
1189
1190         /* Currently only IPv4/IPv6 with TCP is supported */
1191         if (protocol == htons(ETH_P_IP)) {
1192                 if (hdr.ipv4->protocol != IPPROTO_TCP)
1193                         return;
1194
1195                 /* access ihl as a u8 to avoid unaligned access on ia64 */
1196                 hlen = (hdr.network[0] & 0x0F) << 2;
1197         } else if (protocol == htons(ETH_P_IPV6)) {
1198                 if (hdr.ipv6->nexthdr != IPPROTO_TCP)
1199                         return;
1200
1201                 hlen = sizeof(struct ipv6hdr);
1202         } else {
1203                 return;
1204         }
1205
1206         th = (struct tcphdr *)(hdr.network + hlen);
1207
1208         /* sample on all syn/fin packets or once every atr sample rate */
1209         if (!th->fin && !th->syn && (tx_ring->atr_count < tx_ring->atr_sample_rate))
1210                 return;
1211
1212         tx_ring->atr_count = 0;
1213
1214         /* grab the next descriptor */
1215         i = tx_ring->next_to_use;
1216         fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
1217
1218         i++;
1219         tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
1220
1221         flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
1222                       I40E_TXD_FLTR_QW0_QINDEX_MASK;
1223         flex_ptype |= (protocol == htons(ETH_P_IP)) ?
1224                       (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
1225                        I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
1226                       (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
1227                        I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
1228
1229         flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
1230
1231         dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
1232
1233         dtype_cmd |= th->fin ?
1234                      (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
1235                       I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
1236                      (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
1237                       I40E_TXD_FLTR_QW1_PCMD_SHIFT);
1238
1239         dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
1240                      I40E_TXD_FLTR_QW1_DEST_SHIFT;
1241
1242         dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
1243                      I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
1244
1245         fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
1246         fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
1247 }
1248
1249 /**
1250  * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
1251  * @skb:     send buffer
1252  * @tx_ring: ring to send buffer on
1253  * @flags:   the tx flags to be set
1254  *
1255  * Checks the skb and set up correspondingly several generic transmit flags
1256  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
1257  *
1258  * Returns error code indicate the frame should be dropped upon error and the
1259  * otherwise  returns 0 to indicate the flags has been set properly.
1260  **/
1261 static int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
1262                                       struct i40e_ring *tx_ring,
1263                                       u32 *flags)
1264 {
1265         __be16 protocol = skb->protocol;
1266         u32  tx_flags = 0;
1267
1268         /* if we have a HW VLAN tag being added, default to the HW one */
1269         if (vlan_tx_tag_present(skb)) {
1270                 tx_flags |= vlan_tx_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
1271                 tx_flags |= I40E_TX_FLAGS_HW_VLAN;
1272         /* else if it is a SW VLAN, check the next protocol and store the tag */
1273         } else if (protocol == __constant_htons(ETH_P_8021Q)) {
1274                 struct vlan_hdr *vhdr, _vhdr;
1275                 vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
1276                 if (!vhdr)
1277                         return -EINVAL;
1278
1279                 protocol = vhdr->h_vlan_encapsulated_proto;
1280                 tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
1281                 tx_flags |= I40E_TX_FLAGS_SW_VLAN;
1282         }
1283
1284         /* Insert 802.1p priority into VLAN header */
1285         if ((tx_ring->vsi->back->flags & I40E_FLAG_DCB_ENABLED) &&
1286             ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
1287              (skb->priority != TC_PRIO_CONTROL))) {
1288                 tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
1289                 tx_flags |= (skb->priority & 0x7) <<
1290                                 I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
1291                 if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
1292                         struct vlan_ethhdr *vhdr;
1293                         if (skb_header_cloned(skb) &&
1294                             pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
1295                                 return -ENOMEM;
1296                         vhdr = (struct vlan_ethhdr *)skb->data;
1297                         vhdr->h_vlan_TCI = htons(tx_flags >>
1298                                                  I40E_TX_FLAGS_VLAN_SHIFT);
1299                 } else {
1300                         tx_flags |= I40E_TX_FLAGS_HW_VLAN;
1301                 }
1302         }
1303         *flags = tx_flags;
1304         return 0;
1305 }
1306
1307 /**
1308  * i40e_tso - set up the tso context descriptor
1309  * @tx_ring:  ptr to the ring to send
1310  * @skb:      ptr to the skb we're sending
1311  * @tx_flags: the collected send information
1312  * @protocol: the send protocol
1313  * @hdr_len:  ptr to the size of the packet header
1314  * @cd_tunneling: ptr to context descriptor bits
1315  *
1316  * Returns 0 if no TSO can happen, 1 if tso is going, or error
1317  **/
1318 static int i40e_tso(struct i40e_ring *tx_ring, struct sk_buff *skb,
1319                     u32 tx_flags, __be16 protocol, u8 *hdr_len,
1320                     u64 *cd_type_cmd_tso_mss, u32 *cd_tunneling)
1321 {
1322         u32 cd_cmd, cd_tso_len, cd_mss;
1323         struct tcphdr *tcph;
1324         struct iphdr *iph;
1325         u32 l4len;
1326         int err;
1327         struct ipv6hdr *ipv6h;
1328
1329         if (!skb_is_gso(skb))
1330                 return 0;
1331
1332         if (skb_header_cloned(skb)) {
1333                 err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
1334                 if (err)
1335                         return err;
1336         }
1337
1338         if (protocol == __constant_htons(ETH_P_IP)) {
1339                 iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
1340                 tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1341                 iph->tot_len = 0;
1342                 iph->check = 0;
1343                 tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
1344                                                  0, IPPROTO_TCP, 0);
1345         } else if (skb_is_gso_v6(skb)) {
1346
1347                 ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb)
1348                                            : ipv6_hdr(skb);
1349                 tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1350                 ipv6h->payload_len = 0;
1351                 tcph->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
1352                                                0, IPPROTO_TCP, 0);
1353         }
1354
1355         l4len = skb->encapsulation ? inner_tcp_hdrlen(skb) : tcp_hdrlen(skb);
1356         *hdr_len = (skb->encapsulation
1357                     ? (skb_inner_transport_header(skb) - skb->data)
1358                     : skb_transport_offset(skb)) + l4len;
1359
1360         /* find the field values */
1361         cd_cmd = I40E_TX_CTX_DESC_TSO;
1362         cd_tso_len = skb->len - *hdr_len;
1363         cd_mss = skb_shinfo(skb)->gso_size;
1364         *cd_type_cmd_tso_mss |= ((u64)cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT)
1365                              | ((u64)cd_tso_len
1366                                 << I40E_TXD_CTX_QW1_TSO_LEN_SHIFT)
1367                              | ((u64)cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
1368         return 1;
1369 }
1370
1371 /**
1372  * i40e_tx_enable_csum - Enable Tx checksum offloads
1373  * @skb: send buffer
1374  * @tx_flags: Tx flags currently set
1375  * @td_cmd: Tx descriptor command bits to set
1376  * @td_offset: Tx descriptor header offsets to set
1377  * @cd_tunneling: ptr to context desc bits
1378  **/
1379 static void i40e_tx_enable_csum(struct sk_buff *skb, u32 tx_flags,
1380                                 u32 *td_cmd, u32 *td_offset,
1381                                 struct i40e_ring *tx_ring,
1382                                 u32 *cd_tunneling)
1383 {
1384         struct ipv6hdr *this_ipv6_hdr;
1385         unsigned int this_tcp_hdrlen;
1386         struct iphdr *this_ip_hdr;
1387         u32 network_hdr_len;
1388         u8 l4_hdr = 0;
1389
1390         if (skb->encapsulation) {
1391                 network_hdr_len = skb_inner_network_header_len(skb);
1392                 this_ip_hdr = inner_ip_hdr(skb);
1393                 this_ipv6_hdr = inner_ipv6_hdr(skb);
1394                 this_tcp_hdrlen = inner_tcp_hdrlen(skb);
1395
1396                 if (tx_flags & I40E_TX_FLAGS_IPV4) {
1397
1398                         if (tx_flags & I40E_TX_FLAGS_TSO) {
1399                                 *cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
1400                                 ip_hdr(skb)->check = 0;
1401                         } else {
1402                                 *cd_tunneling |=
1403                                          I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
1404                         }
1405                 } else if (tx_flags & I40E_TX_FLAGS_IPV6) {
1406                         if (tx_flags & I40E_TX_FLAGS_TSO) {
1407                                 *cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
1408                                 ip_hdr(skb)->check = 0;
1409                         } else {
1410                                 *cd_tunneling |=
1411                                          I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
1412                         }
1413                 }
1414
1415                 /* Now set the ctx descriptor fields */
1416                 *cd_tunneling |= (skb_network_header_len(skb) >> 2) <<
1417                                         I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT |
1418                                    I40E_TXD_CTX_UDP_TUNNELING            |
1419                                    ((skb_inner_network_offset(skb) -
1420                                         skb_transport_offset(skb)) >> 1) <<
1421                                    I40E_TXD_CTX_QW0_NATLEN_SHIFT;
1422
1423         } else {
1424                 network_hdr_len = skb_network_header_len(skb);
1425                 this_ip_hdr = ip_hdr(skb);
1426                 this_ipv6_hdr = ipv6_hdr(skb);
1427                 this_tcp_hdrlen = tcp_hdrlen(skb);
1428         }
1429
1430         /* Enable IP checksum offloads */
1431         if (tx_flags & I40E_TX_FLAGS_IPV4) {
1432                 l4_hdr = this_ip_hdr->protocol;
1433                 /* the stack computes the IP header already, the only time we
1434                  * need the hardware to recompute it is in the case of TSO.
1435                  */
1436                 if (tx_flags & I40E_TX_FLAGS_TSO) {
1437                         *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4_CSUM;
1438                         this_ip_hdr->check = 0;
1439                 } else {
1440                         *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4;
1441                 }
1442                 /* Now set the td_offset for IP header length */
1443                 *td_offset = (network_hdr_len >> 2) <<
1444                               I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
1445         } else if (tx_flags & I40E_TX_FLAGS_IPV6) {
1446                 l4_hdr = this_ipv6_hdr->nexthdr;
1447                 *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
1448                 /* Now set the td_offset for IP header length */
1449                 *td_offset = (network_hdr_len >> 2) <<
1450                               I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
1451         }
1452         /* words in MACLEN + dwords in IPLEN + dwords in L4Len */
1453         *td_offset |= (skb_network_offset(skb) >> 1) <<
1454                        I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
1455
1456         /* Enable L4 checksum offloads */
1457         switch (l4_hdr) {
1458         case IPPROTO_TCP:
1459                 /* enable checksum offloads */
1460                 *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
1461                 *td_offset |= (this_tcp_hdrlen >> 2) <<
1462                                I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1463                 break;
1464         case IPPROTO_SCTP:
1465                 /* enable SCTP checksum offload */
1466                 *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
1467                 *td_offset |= (sizeof(struct sctphdr) >> 2) <<
1468                                I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1469                 break;
1470         case IPPROTO_UDP:
1471                 /* enable UDP checksum offload */
1472                 *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
1473                 *td_offset |= (sizeof(struct udphdr) >> 2) <<
1474                                I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1475                 break;
1476         default:
1477                 break;
1478         }
1479 }
1480
1481 /**
1482  * i40e_create_tx_ctx Build the Tx context descriptor
1483  * @tx_ring:  ring to create the descriptor on
1484  * @cd_type_cmd_tso_mss: Quad Word 1
1485  * @cd_tunneling: Quad Word 0 - bits 0-31
1486  * @cd_l2tag2: Quad Word 0 - bits 32-63
1487  **/
1488 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
1489                                const u64 cd_type_cmd_tso_mss,
1490                                const u32 cd_tunneling, const u32 cd_l2tag2)
1491 {
1492         struct i40e_tx_context_desc *context_desc;
1493         int i = tx_ring->next_to_use;
1494
1495         if (!cd_type_cmd_tso_mss && !cd_tunneling && !cd_l2tag2)
1496                 return;
1497
1498         /* grab the next descriptor */
1499         context_desc = I40E_TX_CTXTDESC(tx_ring, i);
1500
1501         i++;
1502         tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
1503
1504         /* cpu_to_le32 and assign to struct fields */
1505         context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
1506         context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
1507         context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
1508 }
1509
1510 /**
1511  * i40e_tx_map - Build the Tx descriptor
1512  * @tx_ring:  ring to send buffer on
1513  * @skb:      send buffer
1514  * @first:    first buffer info buffer to use
1515  * @tx_flags: collected send information
1516  * @hdr_len:  size of the packet header
1517  * @td_cmd:   the command field in the descriptor
1518  * @td_offset: offset for checksum or crc
1519  **/
1520 static void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
1521                         struct i40e_tx_buffer *first, u32 tx_flags,
1522                         const u8 hdr_len, u32 td_cmd, u32 td_offset)
1523 {
1524         unsigned int data_len = skb->data_len;
1525         unsigned int size = skb_headlen(skb);
1526         struct skb_frag_struct *frag;
1527         struct i40e_tx_buffer *tx_bi;
1528         struct i40e_tx_desc *tx_desc;
1529         u16 i = tx_ring->next_to_use;
1530         u32 td_tag = 0;
1531         dma_addr_t dma;
1532         u16 gso_segs;
1533
1534         if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
1535                 td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
1536                 td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
1537                          I40E_TX_FLAGS_VLAN_SHIFT;
1538         }
1539
1540         if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO))
1541                 gso_segs = skb_shinfo(skb)->gso_segs;
1542         else
1543                 gso_segs = 1;
1544
1545         /* multiply data chunks by size of headers */
1546         first->bytecount = skb->len - hdr_len + (gso_segs * hdr_len);
1547         first->gso_segs = gso_segs;
1548         first->skb = skb;
1549         first->tx_flags = tx_flags;
1550
1551         dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
1552
1553         tx_desc = I40E_TX_DESC(tx_ring, i);
1554         tx_bi = first;
1555
1556         for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
1557                 if (dma_mapping_error(tx_ring->dev, dma))
1558                         goto dma_error;
1559
1560                 /* record length, and DMA address */
1561                 dma_unmap_len_set(tx_bi, len, size);
1562                 dma_unmap_addr_set(tx_bi, dma, dma);
1563
1564                 tx_desc->buffer_addr = cpu_to_le64(dma);
1565
1566                 while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
1567                         tx_desc->cmd_type_offset_bsz =
1568                                 build_ctob(td_cmd, td_offset,
1569                                            I40E_MAX_DATA_PER_TXD, td_tag);
1570
1571                         tx_desc++;
1572                         i++;
1573                         if (i == tx_ring->count) {
1574                                 tx_desc = I40E_TX_DESC(tx_ring, 0);
1575                                 i = 0;
1576                         }
1577
1578                         dma += I40E_MAX_DATA_PER_TXD;
1579                         size -= I40E_MAX_DATA_PER_TXD;
1580
1581                         tx_desc->buffer_addr = cpu_to_le64(dma);
1582                 }
1583
1584                 if (likely(!data_len))
1585                         break;
1586
1587                 tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
1588                                                           size, td_tag);
1589
1590                 tx_desc++;
1591                 i++;
1592                 if (i == tx_ring->count) {
1593                         tx_desc = I40E_TX_DESC(tx_ring, 0);
1594                         i = 0;
1595                 }
1596
1597                 size = skb_frag_size(frag);
1598                 data_len -= size;
1599
1600                 dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
1601                                        DMA_TO_DEVICE);
1602
1603                 tx_bi = &tx_ring->tx_bi[i];
1604         }
1605
1606         tx_desc->cmd_type_offset_bsz =
1607                 build_ctob(td_cmd, td_offset, size, td_tag) |
1608                 cpu_to_le64((u64)I40E_TXD_CMD << I40E_TXD_QW1_CMD_SHIFT);
1609
1610         netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
1611                                                  tx_ring->queue_index),
1612                              first->bytecount);
1613
1614         /* set the timestamp */
1615         first->time_stamp = jiffies;
1616
1617         /* Force memory writes to complete before letting h/w
1618          * know there are new descriptors to fetch.  (Only
1619          * applicable for weak-ordered memory model archs,
1620          * such as IA-64).
1621          */
1622         wmb();
1623
1624         /* set next_to_watch value indicating a packet is present */
1625         first->next_to_watch = tx_desc;
1626
1627         i++;
1628         if (i == tx_ring->count)
1629                 i = 0;
1630
1631         tx_ring->next_to_use = i;
1632
1633         /* notify HW of packet */
1634         writel(i, tx_ring->tail);
1635
1636         return;
1637
1638 dma_error:
1639         dev_info(tx_ring->dev, "TX DMA map failed\n");
1640
1641         /* clear dma mappings for failed tx_bi map */
1642         for (;;) {
1643                 tx_bi = &tx_ring->tx_bi[i];
1644                 i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
1645                 if (tx_bi == first)
1646                         break;
1647                 if (i == 0)
1648                         i = tx_ring->count;
1649                 i--;
1650         }
1651
1652         tx_ring->next_to_use = i;
1653 }
1654
1655 /**
1656  * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
1657  * @tx_ring: the ring to be checked
1658  * @size:    the size buffer we want to assure is available
1659  *
1660  * Returns -EBUSY if a stop is needed, else 0
1661  **/
1662 static inline int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
1663 {
1664         netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
1665         smp_mb();
1666
1667         /* Check again in a case another CPU has just made room available. */
1668         if (likely(I40E_DESC_UNUSED(tx_ring) < size))
1669                 return -EBUSY;
1670
1671         /* A reprieve! - use start_queue because it doesn't call schedule */
1672         netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
1673         ++tx_ring->tx_stats.restart_queue;
1674         return 0;
1675 }
1676
1677 /**
1678  * i40e_maybe_stop_tx - 1st level check for tx stop conditions
1679  * @tx_ring: the ring to be checked
1680  * @size:    the size buffer we want to assure is available
1681  *
1682  * Returns 0 if stop is not needed
1683  **/
1684 static int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
1685 {
1686         if (likely(I40E_DESC_UNUSED(tx_ring) >= size))
1687                 return 0;
1688         return __i40e_maybe_stop_tx(tx_ring, size);
1689 }
1690
1691 /**
1692  * i40e_xmit_descriptor_count - calculate number of tx descriptors needed
1693  * @skb:     send buffer
1694  * @tx_ring: ring to send buffer on
1695  *
1696  * Returns number of data descriptors needed for this skb. Returns 0 to indicate
1697  * there is not enough descriptors available in this ring since we need at least
1698  * one descriptor.
1699  **/
1700 static int i40e_xmit_descriptor_count(struct sk_buff *skb,
1701                                       struct i40e_ring *tx_ring)
1702 {
1703 #if PAGE_SIZE > I40E_MAX_DATA_PER_TXD
1704         unsigned int f;
1705 #endif
1706         int count = 0;
1707
1708         /* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
1709          *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
1710          *       + 2 desc gap to keep tail from touching head,
1711          *       + 1 desc for context descriptor,
1712          * otherwise try next time
1713          */
1714 #if PAGE_SIZE > I40E_MAX_DATA_PER_TXD
1715         for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
1716                 count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
1717 #else
1718         count += skb_shinfo(skb)->nr_frags;
1719 #endif
1720         count += TXD_USE_COUNT(skb_headlen(skb));
1721         if (i40e_maybe_stop_tx(tx_ring, count + 3)) {
1722                 tx_ring->tx_stats.tx_busy++;
1723                 return 0;
1724         }
1725         return count;
1726 }
1727
1728 /**
1729  * i40e_xmit_frame_ring - Sends buffer on Tx ring
1730  * @skb:     send buffer
1731  * @tx_ring: ring to send buffer on
1732  *
1733  * Returns NETDEV_TX_OK if sent, else an error code
1734  **/
1735 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
1736                                         struct i40e_ring *tx_ring)
1737 {
1738         u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
1739         u32 cd_tunneling = 0, cd_l2tag2 = 0;
1740         struct i40e_tx_buffer *first;
1741         u32 td_offset = 0;
1742         u32 tx_flags = 0;
1743         __be16 protocol;
1744         u32 td_cmd = 0;
1745         u8 hdr_len = 0;
1746         int tso;
1747         if (0 == i40e_xmit_descriptor_count(skb, tx_ring))
1748                 return NETDEV_TX_BUSY;
1749
1750         /* prepare the xmit flags */
1751         if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
1752                 goto out_drop;
1753
1754         /* obtain protocol of skb */
1755         protocol = skb->protocol;
1756
1757         /* record the location of the first descriptor for this packet */
1758         first = &tx_ring->tx_bi[tx_ring->next_to_use];
1759
1760         /* setup IPv4/IPv6 offloads */
1761         if (protocol == __constant_htons(ETH_P_IP))
1762                 tx_flags |= I40E_TX_FLAGS_IPV4;
1763         else if (protocol == __constant_htons(ETH_P_IPV6))
1764                 tx_flags |= I40E_TX_FLAGS_IPV6;
1765
1766         tso = i40e_tso(tx_ring, skb, tx_flags, protocol, &hdr_len,
1767                        &cd_type_cmd_tso_mss, &cd_tunneling);
1768
1769         if (tso < 0)
1770                 goto out_drop;
1771         else if (tso)
1772                 tx_flags |= I40E_TX_FLAGS_TSO;
1773
1774         skb_tx_timestamp(skb);
1775
1776         /* always enable CRC insertion offload */
1777         td_cmd |= I40E_TX_DESC_CMD_ICRC;
1778
1779         /* Always offload the checksum, since it's in the data descriptor */
1780         if (skb->ip_summed == CHECKSUM_PARTIAL) {
1781                 tx_flags |= I40E_TX_FLAGS_CSUM;
1782
1783                 i40e_tx_enable_csum(skb, tx_flags, &td_cmd, &td_offset,
1784                                     tx_ring, &cd_tunneling);
1785         }
1786
1787         i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
1788                            cd_tunneling, cd_l2tag2);
1789
1790         /* Add Flow Director ATR if it's enabled.
1791          *
1792          * NOTE: this must always be directly before the data descriptor.
1793          */
1794         i40e_atr(tx_ring, skb, tx_flags, protocol);
1795
1796         i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
1797                     td_cmd, td_offset);
1798
1799         i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
1800
1801         return NETDEV_TX_OK;
1802
1803 out_drop:
1804         dev_kfree_skb_any(skb);
1805         return NETDEV_TX_OK;
1806 }
1807
1808 /**
1809  * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
1810  * @skb:    send buffer
1811  * @netdev: network interface device structure
1812  *
1813  * Returns NETDEV_TX_OK if sent, else an error code
1814  **/
1815 netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
1816 {
1817         struct i40e_netdev_priv *np = netdev_priv(netdev);
1818         struct i40e_vsi *vsi = np->vsi;
1819         struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
1820
1821         /* hardware can't handle really short frames, hardware padding works
1822          * beyond this point
1823          */
1824         if (unlikely(skb->len < I40E_MIN_TX_LEN)) {
1825                 if (skb_pad(skb, I40E_MIN_TX_LEN - skb->len))
1826                         return NETDEV_TX_OK;
1827                 skb->len = I40E_MIN_TX_LEN;
1828                 skb_set_tail_pointer(skb, I40E_MIN_TX_LEN);
1829         }
1830
1831         return i40e_xmit_frame_ring(skb, tx_ring);
1832 }