root/drivers/net/ethernet/amd/xgbe/xgbe-desc.c

DEFINITIONS

1. xgbe_free_ring
2. xgbe_free_ring_resources
3. xgbe_alloc_node
4. xgbe_dma_alloc_node
5. xgbe_init_ring
6. xgbe_alloc_ring_resources
7. xgbe_alloc_pages
8. xgbe_set_buffer_data
9. xgbe_map_rx_buffer
10. xgbe_wrapper_tx_descriptor_init
11. xgbe_wrapper_rx_descriptor_init
12. xgbe_unmap_rdata
13. xgbe_map_tx_skb
14. xgbe_init_function_ptrs_desc

   1 /*
   2  * AMD 10Gb Ethernet driver
   3  *
   4  * This file is available to you under your choice of the following two
   5  * licenses:
   6  *
   7  * License 1: GPLv2
   8  *
   9  * Copyright (c) 2014 Advanced Micro Devices, Inc.
  10  *
  11  * This file is free software; you may copy, redistribute and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation, either version 2 of the License, or (at
  14  * your option) any later version.
  15  *
  16  * This file is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19  * General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  *
  24  * This file incorporates work covered by the following copyright and
  25  * permission notice:
  26  *     The Synopsys DWC ETHER XGMAC Software Driver and documentation
  27  *     (hereinafter "Software") is an unsupported proprietary work of Synopsys,
  28  *     Inc. unless otherwise expressly agreed to in writing between Synopsys
  29  *     and you.
  30  *
  31  *     The Software IS NOT an item of Licensed Software or Licensed Product
  32  *     under any End User Software License Agreement or Agreement for Licensed
  33  *     Product with Synopsys or any supplement thereto.  Permission is hereby
  34  *     granted, free of charge, to any person obtaining a copy of this software
  35  *     annotated with this license and the Software, to deal in the Software
  36  *     without restriction, including without limitation the rights to use,
  37  *     copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  38  *     of the Software, and to permit persons to whom the Software is furnished
  39  *     to do so, subject to the following conditions:
  40  *
  41  *     The above copyright notice and this permission notice shall be included
  42  *     in all copies or substantial portions of the Software.
  43  *
  44  *     THIS SOFTWARE IS BEING DISTRIBUTED BY SYNOPSYS SOLELY ON AN "AS IS"
  45  *     BASIS AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  46  *     TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  47  *     PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. IN NO EVENT SHALL SYNOPSYS
  48  *     BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  49  *     CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  50  *     SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  51  *     INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  52  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  53  *     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  54  *     THE POSSIBILITY OF SUCH DAMAGE.
  55  *
  56  *
  57  * License 2: Modified BSD
  58  *
  59  * Copyright (c) 2014 Advanced Micro Devices, Inc.
  60  * All rights reserved.
  61  *
  62  * Redistribution and use in source and binary forms, with or without
  63  * modification, are permitted provided that the following conditions are met:
  64  *     * Redistributions of source code must retain the above copyright
  65  *       notice, this list of conditions and the following disclaimer.
  66  *     * Redistributions in binary form must reproduce the above copyright
  67  *       notice, this list of conditions and the following disclaimer in the
  68  *       documentation and/or other materials provided with the distribution.
  69  *     * Neither the name of Advanced Micro Devices, Inc. nor the
  70  *       names of its contributors may be used to endorse or promote products
  71  *       derived from this software without specific prior written permission.
  72  *
  73  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  74  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  75  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  76  * ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
  77  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  78  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  79  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  80  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  81  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  82  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  83  *
  84  * This file incorporates work covered by the following copyright and
  85  * permission notice:
  86  *     The Synopsys DWC ETHER XGMAC Software Driver and documentation
  87  *     (hereinafter "Software") is an unsupported proprietary work of Synopsys,
  88  *     Inc. unless otherwise expressly agreed to in writing between Synopsys
  89  *     and you.
  90  *
  91  *     The Software IS NOT an item of Licensed Software or Licensed Product
  92  *     under any End User Software License Agreement or Agreement for Licensed
  93  *     Product with Synopsys or any supplement thereto.  Permission is hereby
  94  *     granted, free of charge, to any person obtaining a copy of this software
  95  *     annotated with this license and the Software, to deal in the Software
  96  *     without restriction, including without limitation the rights to use,
  97  *     copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  98  *     of the Software, and to permit persons to whom the Software is furnished
  99  *     to do so, subject to the following conditions:
 100  *
 101  *     The above copyright notice and this permission notice shall be included
 102  *     in all copies or substantial portions of the Software.
 103  *
 104  *     THIS SOFTWARE IS BEING DISTRIBUTED BY SYNOPSYS SOLELY ON AN "AS IS"
 105  *     BASIS AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 106  *     TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 107  *     PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. IN NO EVENT SHALL SYNOPSYS
 108  *     BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 109  *     CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 110  *     SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 111  *     INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 112  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 113  *     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 114  *     THE POSSIBILITY OF SUCH DAMAGE.
 115  */
 116 
 117 #include "xgbe.h"
 118 #include "xgbe-common.h"
 119 
 120 static void xgbe_unmap_rdata(struct xgbe_prv_data *, struct xgbe_ring_data *);
 121 
 122 static void xgbe_free_ring(struct xgbe_prv_data *pdata,
 123                            struct xgbe_ring *ring)
 124 {
 125         struct xgbe_ring_data *rdata;
 126         unsigned int i;
 127 
 128         if (!ring)
 129                 return;
 130 
 131         if (ring->rdata) {
 132                 for (i = 0; i < ring->rdesc_count; i++) {
 133                         rdata = XGBE_GET_DESC_DATA(ring, i);
 134                         xgbe_unmap_rdata(pdata, rdata);
 135                 }
 136 
 137                 kfree(ring->rdata);
 138                 ring->rdata = NULL;
 139         }
 140 
 141         if (ring->rx_hdr_pa.pages) {
 142                 dma_unmap_page(pdata->dev, ring->rx_hdr_pa.pages_dma,
 143                                ring->rx_hdr_pa.pages_len, DMA_FROM_DEVICE);
 144                 put_page(ring->rx_hdr_pa.pages);
 145 
 146                 ring->rx_hdr_pa.pages = NULL;
 147                 ring->rx_hdr_pa.pages_len = 0;
 148                 ring->rx_hdr_pa.pages_offset = 0;
 149                 ring->rx_hdr_pa.pages_dma = 0;
 150         }
 151 
 152         if (ring->rx_buf_pa.pages) {
 153                 dma_unmap_page(pdata->dev, ring->rx_buf_pa.pages_dma,
 154                                ring->rx_buf_pa.pages_len, DMA_FROM_DEVICE);
 155                 put_page(ring->rx_buf_pa.pages);
 156 
 157                 ring->rx_buf_pa.pages = NULL;
 158                 ring->rx_buf_pa.pages_len = 0;
 159                 ring->rx_buf_pa.pages_offset = 0;
 160                 ring->rx_buf_pa.pages_dma = 0;
 161         }
 162 
 163         if (ring->rdesc) {
 164                 dma_free_coherent(pdata->dev,
 165                                   (sizeof(struct xgbe_ring_desc) *
 166                                    ring->rdesc_count),
 167                                   ring->rdesc, ring->rdesc_dma);
 168                 ring->rdesc = NULL;
 169         }
 170 }
 171 
 172 static void xgbe_free_ring_resources(struct xgbe_prv_data *pdata)
 173 {
 174         struct xgbe_channel *channel;
 175         unsigned int i;
 176 
 177         DBGPR("-->xgbe_free_ring_resources\n");
 178 
 179         for (i = 0; i < pdata->channel_count; i++) {
 180                 channel = pdata->channel[i];
 181                 xgbe_free_ring(pdata, channel->tx_ring);
 182                 xgbe_free_ring(pdata, channel->rx_ring);
 183         }
 184 
 185         DBGPR("<--xgbe_free_ring_resources\n");
 186 }
 187 
 188 static void *xgbe_alloc_node(size_t size, int node)
 189 {
 190         void *mem;
 191 
 192         mem = kzalloc_node(size, GFP_KERNEL, node);
 193         if (!mem)
 194                 mem = kzalloc(size, GFP_KERNEL);
 195 
 196         return mem;
 197 }
 198 
 199 static void *xgbe_dma_alloc_node(struct device *dev, size_t size,
 200                                  dma_addr_t *dma, int node)
 201 {
 202         void *mem;
 203         int cur_node = dev_to_node(dev);
 204 
 205         set_dev_node(dev, node);
 206         mem = dma_alloc_coherent(dev, size, dma, GFP_KERNEL);
 207         set_dev_node(dev, cur_node);
 208 
 209         if (!mem)
 210                 mem = dma_alloc_coherent(dev, size, dma, GFP_KERNEL);
 211 
 212         return mem;
 213 }
 214 
 215 static int xgbe_init_ring(struct xgbe_prv_data *pdata,
 216                           struct xgbe_ring *ring, unsigned int rdesc_count)
 217 {
 218         size_t size;
 219 
 220         if (!ring)
 221                 return 0;
 222 
 223         /* Descriptors */
 224         size = rdesc_count * sizeof(struct xgbe_ring_desc);
 225 
 226         ring->rdesc_count = rdesc_count;
 227         ring->rdesc = xgbe_dma_alloc_node(pdata->dev, size, &ring->rdesc_dma,
 228                                           ring->node);
 229         if (!ring->rdesc)
 230                 return -ENOMEM;
 231 
 232         /* Descriptor information */
 233         size = rdesc_count * sizeof(struct xgbe_ring_data);
 234 
 235         ring->rdata = xgbe_alloc_node(size, ring->node);
 236         if (!ring->rdata)
 237                 return -ENOMEM;
 238 
 239         netif_dbg(pdata, drv, pdata->netdev,
 240                   "rdesc=%p, rdesc_dma=%pad, rdata=%p, node=%d\n",
 241                   ring->rdesc, &ring->rdesc_dma, ring->rdata, ring->node);
 242 
 243         return 0;
 244 }
 245 
 246 static int xgbe_alloc_ring_resources(struct xgbe_prv_data *pdata)
 247 {
 248         struct xgbe_channel *channel;
 249         unsigned int i;
 250         int ret;
 251 
 252         for (i = 0; i < pdata->channel_count; i++) {
 253                 channel = pdata->channel[i];
 254                 netif_dbg(pdata, drv, pdata->netdev, "%s - Tx ring:\n",
 255                           channel->name);
 256 
 257                 ret = xgbe_init_ring(pdata, channel->tx_ring,
 258                                      pdata->tx_desc_count);
 259                 if (ret) {
 260                         netdev_alert(pdata->netdev,
 261                                      "error initializing Tx ring\n");
 262                         goto err_ring;
 263                 }
 264 
 265                 netif_dbg(pdata, drv, pdata->netdev, "%s - Rx ring:\n",
 266                           channel->name);
 267 
 268                 ret = xgbe_init_ring(pdata, channel->rx_ring,
 269                                      pdata->rx_desc_count);
 270                 if (ret) {
 271                         netdev_alert(pdata->netdev,
 272                                      "error initializing Rx ring\n");
 273                         goto err_ring;
 274                 }
 275         }
 276 
 277         return 0;
 278 
 279 err_ring:
 280         xgbe_free_ring_resources(pdata);
 281 
 282         return ret;
 283 }
 284 
 285 static int xgbe_alloc_pages(struct xgbe_prv_data *pdata,
 286                             struct xgbe_page_alloc *pa, int alloc_order,
 287                             int node)
 288 {
 289         struct page *pages = NULL;
 290         dma_addr_t pages_dma;
 291         gfp_t gfp;
 292         int order;
 293 
 294 again:
 295         order = alloc_order;
 296 
 297         /* Try to obtain pages, decreasing order if necessary */
 298         gfp = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
 299         while (order >= 0) {
 300                 pages = alloc_pages_node(node, gfp, order);
 301                 if (pages)
 302                         break;
 303 
 304                 order--;
 305         }
 306 
 307         /* If we couldn't get local pages, try getting from anywhere */
 308         if (!pages && (node != NUMA_NO_NODE)) {
 309                 node = NUMA_NO_NODE;
 310                 goto again;
 311         }
 312 
 313         if (!pages)
 314                 return -ENOMEM;
 315 
 316         /* Map the pages */
 317         pages_dma = dma_map_page(pdata->dev, pages, 0,
 318                                  PAGE_SIZE << order, DMA_FROM_DEVICE);
 319         if (dma_mapping_error(pdata->dev, pages_dma)) {
 320                 put_page(pages);
 321                 return -ENOMEM;
 322         }
 323 
 324         pa->pages = pages;
 325         pa->pages_len = PAGE_SIZE << order;
 326         pa->pages_offset = 0;
 327         pa->pages_dma = pages_dma;
 328 
 329         return 0;
 330 }
 331 
 332 static void xgbe_set_buffer_data(struct xgbe_buffer_data *bd,
 333                                  struct xgbe_page_alloc *pa,
 334                                  unsigned int len)
 335 {
 336         get_page(pa->pages);
 337         bd->pa = *pa;
 338 
 339         bd->dma_base = pa->pages_dma;
 340         bd->dma_off = pa->pages_offset;
 341         bd->dma_len = len;
 342 
 343         pa->pages_offset += len;
 344         if ((pa->pages_offset + len) > pa->pages_len) {
 345                 /* This data descriptor is responsible for unmapping page(s) */
 346                 bd->pa_unmap = *pa;
 347 
 348                 /* Get a new allocation next time */
 349                 pa->pages = NULL;
 350                 pa->pages_len = 0;
 351                 pa->pages_offset = 0;
 352                 pa->pages_dma = 0;
 353         }
 354 }
 355 
 356 static int xgbe_map_rx_buffer(struct xgbe_prv_data *pdata,
 357                               struct xgbe_ring *ring,
 358                               struct xgbe_ring_data *rdata)
 359 {
 360         int ret;
 361 
 362         if (!ring->rx_hdr_pa.pages) {
 363                 ret = xgbe_alloc_pages(pdata, &ring->rx_hdr_pa, 0, ring->node);
 364                 if (ret)
 365                         return ret;
 366         }
 367 
 368         if (!ring->rx_buf_pa.pages) {
 369                 ret = xgbe_alloc_pages(pdata, &ring->rx_buf_pa,
 370                                        PAGE_ALLOC_COSTLY_ORDER, ring->node);
 371                 if (ret)
 372                         return ret;
 373         }
 374 
 375         /* Set up the header page info */
 376         xgbe_set_buffer_data(&rdata->rx.hdr, &ring->rx_hdr_pa,
 377                              XGBE_SKB_ALLOC_SIZE);
 378 
 379         /* Set up the buffer page info */
 380         xgbe_set_buffer_data(&rdata->rx.buf, &ring->rx_buf_pa,
 381                              pdata->rx_buf_size);
 382 
 383         return 0;
 384 }
 385 
 386 static void xgbe_wrapper_tx_descriptor_init(struct xgbe_prv_data *pdata)
 387 {
 388         struct xgbe_hw_if *hw_if = &pdata->hw_if;
 389         struct xgbe_channel *channel;
 390         struct xgbe_ring *ring;
 391         struct xgbe_ring_data *rdata;
 392         struct xgbe_ring_desc *rdesc;
 393         dma_addr_t rdesc_dma;
 394         unsigned int i, j;
 395 
 396         DBGPR("-->xgbe_wrapper_tx_descriptor_init\n");
 397 
 398         for (i = 0; i < pdata->channel_count; i++) {
 399                 channel = pdata->channel[i];
 400                 ring = channel->tx_ring;
 401                 if (!ring)
 402                         break;
 403 
 404                 rdesc = ring->rdesc;
 405                 rdesc_dma = ring->rdesc_dma;
 406 
 407                 for (j = 0; j < ring->rdesc_count; j++) {
 408                         rdata = XGBE_GET_DESC_DATA(ring, j);
 409 
 410                         rdata->rdesc = rdesc;
 411                         rdata->rdesc_dma = rdesc_dma;
 412 
 413                         rdesc++;
 414                         rdesc_dma += sizeof(struct xgbe_ring_desc);
 415                 }
 416 
 417                 ring->cur = 0;
 418                 ring->dirty = 0;
 419                 memset(&ring->tx, 0, sizeof(ring->tx));
 420 
 421                 hw_if->tx_desc_init(channel);
 422         }
 423 
 424         DBGPR("<--xgbe_wrapper_tx_descriptor_init\n");
 425 }
 426 
 427 static void xgbe_wrapper_rx_descriptor_init(struct xgbe_prv_data *pdata)
 428 {
 429         struct xgbe_hw_if *hw_if = &pdata->hw_if;
 430         struct xgbe_channel *channel;
 431         struct xgbe_ring *ring;
 432         struct xgbe_ring_desc *rdesc;
 433         struct xgbe_ring_data *rdata;
 434         dma_addr_t rdesc_dma;
 435         unsigned int i, j;
 436 
 437         DBGPR("-->xgbe_wrapper_rx_descriptor_init\n");
 438 
 439         for (i = 0; i < pdata->channel_count; i++) {
 440                 channel = pdata->channel[i];
 441                 ring = channel->rx_ring;
 442                 if (!ring)
 443                         break;
 444 
 445                 rdesc = ring->rdesc;
 446                 rdesc_dma = ring->rdesc_dma;
 447 
 448                 for (j = 0; j < ring->rdesc_count; j++) {
 449                         rdata = XGBE_GET_DESC_DATA(ring, j);
 450 
 451                         rdata->rdesc = rdesc;
 452                         rdata->rdesc_dma = rdesc_dma;
 453 
 454                         if (xgbe_map_rx_buffer(pdata, ring, rdata))
 455                                 break;
 456 
 457                         rdesc++;
 458                         rdesc_dma += sizeof(struct xgbe_ring_desc);
 459                 }
 460 
 461                 ring->cur = 0;
 462                 ring->dirty = 0;
 463 
 464                 hw_if->rx_desc_init(channel);
 465         }
 466 
 467         DBGPR("<--xgbe_wrapper_rx_descriptor_init\n");
 468 }
 469 
 470 static void xgbe_unmap_rdata(struct xgbe_prv_data *pdata,
 471                              struct xgbe_ring_data *rdata)
 472 {
 473         if (rdata->skb_dma) {
 474                 if (rdata->mapped_as_page) {
 475                         dma_unmap_page(pdata->dev, rdata->skb_dma,
 476                                        rdata->skb_dma_len, DMA_TO_DEVICE);
 477                 } else {
 478                         dma_unmap_single(pdata->dev, rdata->skb_dma,
 479                                          rdata->skb_dma_len, DMA_TO_DEVICE);
 480                 }
 481                 rdata->skb_dma = 0;
 482                 rdata->skb_dma_len = 0;
 483         }
 484 
 485         if (rdata->skb) {
 486                 dev_kfree_skb_any(rdata->skb);
 487                 rdata->skb = NULL;
 488         }
 489 
 490         if (rdata->rx.hdr.pa.pages)
 491                 put_page(rdata->rx.hdr.pa.pages);
 492 
 493         if (rdata->rx.hdr.pa_unmap.pages) {
 494                 dma_unmap_page(pdata->dev, rdata->rx.hdr.pa_unmap.pages_dma,
 495                                rdata->rx.hdr.pa_unmap.pages_len,
 496                                DMA_FROM_DEVICE);
 497                 put_page(rdata->rx.hdr.pa_unmap.pages);
 498         }
 499 
 500         if (rdata->rx.buf.pa.pages)
 501                 put_page(rdata->rx.buf.pa.pages);
 502 
 503         if (rdata->rx.buf.pa_unmap.pages) {
 504                 dma_unmap_page(pdata->dev, rdata->rx.buf.pa_unmap.pages_dma,
 505                                rdata->rx.buf.pa_unmap.pages_len,
 506                                DMA_FROM_DEVICE);
 507                 put_page(rdata->rx.buf.pa_unmap.pages);
 508         }
 509 
 510         memset(&rdata->tx, 0, sizeof(rdata->tx));
 511         memset(&rdata->rx, 0, sizeof(rdata->rx));
 512 
 513         rdata->mapped_as_page = 0;
 514 
 515         if (rdata->state_saved) {
 516                 rdata->state_saved = 0;
 517                 rdata->state.skb = NULL;
 518                 rdata->state.len = 0;
 519                 rdata->state.error = 0;
 520         }
 521 }
 522 
 523 static int xgbe_map_tx_skb(struct xgbe_channel *channel, struct sk_buff *skb)
 524 {
 525         struct xgbe_prv_data *pdata = channel->pdata;
 526         struct xgbe_ring *ring = channel->tx_ring;
 527         struct xgbe_ring_data *rdata;
 528         struct xgbe_packet_data *packet;
 529         skb_frag_t *frag;
 530         dma_addr_t skb_dma;
 531         unsigned int start_index, cur_index;
 532         unsigned int offset, tso, vlan, datalen, len;
 533         unsigned int i;
 534 
 535         DBGPR("-->xgbe_map_tx_skb: cur = %d\n", ring->cur);
 536 
 537         offset = 0;
 538         start_index = ring->cur;
 539         cur_index = ring->cur;
 540 
 541         packet = &ring->packet_data;
 542         packet->rdesc_count = 0;
 543         packet->length = 0;
 544 
 545         tso = XGMAC_GET_BITS(packet->attributes, TX_PACKET_ATTRIBUTES,
 546                              TSO_ENABLE);
 547         vlan = XGMAC_GET_BITS(packet->attributes, TX_PACKET_ATTRIBUTES,
 548                               VLAN_CTAG);
 549 
 550         /* Save space for a context descriptor if needed */
 551         if ((tso && (packet->mss != ring->tx.cur_mss)) ||
 552             (vlan && (packet->vlan_ctag != ring->tx.cur_vlan_ctag)))
 553                 cur_index++;
 554         rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 555 
 556         if (tso) {
 557                 /* Map the TSO header */
 558                 skb_dma = dma_map_single(pdata->dev, skb->data,
 559                                          packet->header_len, DMA_TO_DEVICE);
 560                 if (dma_mapping_error(pdata->dev, skb_dma)) {
 561                         netdev_alert(pdata->netdev, "dma_map_single failed\n");
 562                         goto err_out;
 563                 }
 564                 rdata->skb_dma = skb_dma;
 565                 rdata->skb_dma_len = packet->header_len;
 566                 netif_dbg(pdata, tx_queued, pdata->netdev,
 567                           "skb header: index=%u, dma=%pad, len=%u\n",
 568                           cur_index, &skb_dma, packet->header_len);
 569 
 570                 offset = packet->header_len;
 571 
 572                 packet->length += packet->header_len;
 573 
 574                 cur_index++;
 575                 rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 576         }
 577 
 578         /* Map the (remainder of the) packet */
 579         for (datalen = skb_headlen(skb) - offset; datalen; ) {
 580                 len = min_t(unsigned int, datalen, XGBE_TX_MAX_BUF_SIZE);
 581 
 582                 skb_dma = dma_map_single(pdata->dev, skb->data + offset, len,
 583                                          DMA_TO_DEVICE);
 584                 if (dma_mapping_error(pdata->dev, skb_dma)) {
 585                         netdev_alert(pdata->netdev, "dma_map_single failed\n");
 586                         goto err_out;
 587                 }
 588                 rdata->skb_dma = skb_dma;
 589                 rdata->skb_dma_len = len;
 590                 netif_dbg(pdata, tx_queued, pdata->netdev,
 591                           "skb data: index=%u, dma=%pad, len=%u\n",
 592                           cur_index, &skb_dma, len);
 593 
 594                 datalen -= len;
 595                 offset += len;
 596 
 597                 packet->length += len;
 598 
 599                 cur_index++;
 600                 rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 601         }
 602 
 603         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 604                 netif_dbg(pdata, tx_queued, pdata->netdev,
 605                           "mapping frag %u\n", i);
 606 
 607                 frag = &skb_shinfo(skb)->frags[i];
 608                 offset = 0;
 609 
 610                 for (datalen = skb_frag_size(frag); datalen; ) {
 611                         len = min_t(unsigned int, datalen,
 612                                     XGBE_TX_MAX_BUF_SIZE);
 613 
 614                         skb_dma = skb_frag_dma_map(pdata->dev, frag, offset,
 615                                                    len, DMA_TO_DEVICE);
 616                         if (dma_mapping_error(pdata->dev, skb_dma)) {
 617                                 netdev_alert(pdata->netdev,
 618                                              "skb_frag_dma_map failed\n");
 619                                 goto err_out;
 620                         }
 621                         rdata->skb_dma = skb_dma;
 622                         rdata->skb_dma_len = len;
 623                         rdata->mapped_as_page = 1;
 624                         netif_dbg(pdata, tx_queued, pdata->netdev,
 625                                   "skb frag: index=%u, dma=%pad, len=%u\n",
 626                                   cur_index, &skb_dma, len);
 627 
 628                         datalen -= len;
 629                         offset += len;
 630 
 631                         packet->length += len;
 632 
 633                         cur_index++;
 634                         rdata = XGBE_GET_DESC_DATA(ring, cur_index);
 635                 }
 636         }
 637 
 638         /* Save the skb address in the last entry. We always have some data
 639          * that has been mapped so rdata is always advanced past the last
 640          * piece of mapped data - use the entry pointed to by cur_index - 1.
 641          */
 642         rdata = XGBE_GET_DESC_DATA(ring, cur_index - 1);
 643         rdata->skb = skb;
 644 
 645         /* Save the number of descriptor entries used */
 646         packet->rdesc_count = cur_index - start_index;
 647 
 648         DBGPR("<--xgbe_map_tx_skb: count=%u\n", packet->rdesc_count);
 649 
 650         return packet->rdesc_count;
 651 
 652 err_out:
 653         while (start_index < cur_index) {
 654                 rdata = XGBE_GET_DESC_DATA(ring, start_index++);
 655                 xgbe_unmap_rdata(pdata, rdata);
 656         }
 657 
 658         DBGPR("<--xgbe_map_tx_skb: count=0\n");
 659 
 660         return 0;
 661 }
 662 
 663 void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
 664 {
 665         DBGPR("-->xgbe_init_function_ptrs_desc\n");
 666 
 667         desc_if->alloc_ring_resources = xgbe_alloc_ring_resources;
 668         desc_if->free_ring_resources = xgbe_free_ring_resources;
 669         desc_if->map_tx_skb = xgbe_map_tx_skb;
 670         desc_if->map_rx_buffer = xgbe_map_rx_buffer;
 671         desc_if->unmap_rdata = xgbe_unmap_rdata;
 672         desc_if->wrapper_tx_desc_init = xgbe_wrapper_tx_descriptor_init;
 673         desc_if->wrapper_rx_desc_init = xgbe_wrapper_rx_descriptor_init;
 674 
 675         DBGPR("<--xgbe_init_function_ptrs_desc\n");
 676 }