drivers/net/ethernet/synopsys/dwc-xlgmac-net.c

   1 /* Synopsys DesignWare Core Enterprise Ethernet (XLGMAC) Driver
   2  *
   3  * Copyright (c) 2017 Synopsys, Inc. (www.synopsys.com)
   4  *
   5  * This program is dual-licensed; you may select either version 2 of
   6  * the GNU General Public License ("GPL") or BSD license ("BSD").
   7  *
   8  * This Synopsys DWC XLGMAC software driver and associated documentation
   9  * (hereinafter the "Software") is an unsupported proprietary work of
  10  * Synopsys, Inc. unless otherwise expressly agreed to in writing between
  11  * Synopsys and you. The Software IS NOT an item of Licensed Software or a
  12  * Licensed Product under any End User Software License Agreement or
  13  * Agreement for Licensed Products with Synopsys or any supplement thereto.
  14  * Synopsys is a registered trademark of Synopsys, Inc. Other names included
  15  * in the SOFTWARE may be the trademarks of their respective owners.
  16  */
  17
  18 #include <linux/netdevice.h>
  19 #include <linux/tcp.h>
  20 #include <linux/interrupt.h>
  21
  22 #include "dwc-xlgmac.h"
  23 #include "dwc-xlgmac-reg.h"
  24
  25 static int xlgmac_one_poll(struct napi_struct *, int);
  26 static int xlgmac_all_poll(struct napi_struct *, int);
  27
  28 static inline unsigned int xlgmac_tx_avail_desc(struct xlgmac_ring *ring)
  29 {
  30         return (ring->dma_desc_count - (ring->cur - ring->dirty));
  31 }
  32
  33 static inline unsigned int xlgmac_rx_dirty_desc(struct xlgmac_ring *ring)
  34 {
  35         return (ring->cur - ring->dirty);
  36 }
  37
  38 static int xlgmac_maybe_stop_tx_queue(
  39                         struct xlgmac_channel *channel,
  40                         struct xlgmac_ring *ring,
  41                         unsigned int count)
  42 {
  43         struct xlgmac_pdata *pdata = channel->pdata;
  44
  45         if (count > xlgmac_tx_avail_desc(ring)) {
  46                 netif_info(pdata, drv, pdata->netdev,
  47                            "Tx queue stopped, not enough descriptors available\n");
  48                 netif_stop_subqueue(pdata->netdev, channel->queue_index);
  49                 ring->tx.queue_stopped = 1;
  50
  51                 /* If we haven't notified the hardware because of xmit_more
  52                  * support, tell it now
  53                  */
  54                 if (ring->tx.xmit_more)
  55                         pdata->hw_ops.tx_start_xmit(channel, ring);
  56
  57                 return NETDEV_TX_BUSY;
  58         }
  59
  60         return 0;
  61 }
  62
  63 static void xlgmac_prep_vlan(struct sk_buff *skb,
  64                              struct xlgmac_pkt_info *pkt_info)
  65 {
  66         if (skb_vlan_tag_present(skb))
  67                 pkt_info->vlan_ctag = skb_vlan_tag_get(skb);
  68 }
  69
  70 static int xlgmac_prep_tso(struct sk_buff *skb,
  71                            struct xlgmac_pkt_info *pkt_info)
  72 {
  73         int ret;
  74
  75         if (!XLGMAC_GET_REG_BITS(pkt_info->attributes,
  76                                  TX_PACKET_ATTRIBUTES_TSO_ENABLE_POS,
  77                                  TX_PACKET_ATTRIBUTES_TSO_ENABLE_LEN))
  78                 return 0;
  79
  80         ret = skb_cow_head(skb, 0);
  81         if (ret)
  82                 return ret;
  83
  84         pkt_info->header_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
  85         pkt_info->tcp_header_len = tcp_hdrlen(skb);
  86         pkt_info->tcp_payload_len = skb->len - pkt_info->header_len;
  87         pkt_info->mss = skb_shinfo(skb)->gso_size;
  88
  89         XLGMAC_PR("header_len=%u\n", pkt_info->header_len);
  90         XLGMAC_PR("tcp_header_len=%u, tcp_payload_len=%u\n",
  91                   pkt_info->tcp_header_len, pkt_info->tcp_payload_len);
  92         XLGMAC_PR("mss=%u\n", pkt_info->mss);
  93
  94         /* Update the number of packets that will ultimately be transmitted
  95          * along with the extra bytes for each extra packet
  96          */
  97         pkt_info->tx_packets = skb_shinfo(skb)->gso_segs;
  98         pkt_info->tx_bytes += (pkt_info->tx_packets - 1) * pkt_info->header_len;
  99
 100         return 0;
 101 }
 102
 103 static int xlgmac_is_tso(struct sk_buff *skb)
 104 {
 105         if (skb->ip_summed != CHECKSUM_PARTIAL)
 106                 return 0;
 107
 108         if (!skb_is_gso(skb))
 109                 return 0;
 110
 111         return 1;
 112 }
 113
 114 static void xlgmac_prep_tx_pkt(struct xlgmac_pdata *pdata,
 115                                struct xlgmac_ring *ring,
 116                                struct sk_buff *skb,
 117                                struct xlgmac_pkt_info *pkt_info)
 118 {
 119         struct skb_frag_struct *frag;
 120         unsigned int context_desc;
 121         unsigned int len;
 122         unsigned int i;
 123
 124         pkt_info->skb = skb;
 125
 126         context_desc = 0;
 127         pkt_info->desc_count = 0;
 128
 129         pkt_info->tx_packets = 1;
 130         pkt_info->tx_bytes = skb->len;
 131
 132         if (xlgmac_is_tso(skb)) {
 133                 /* TSO requires an extra descriptor if mss is different */
 134                 if (skb_shinfo(skb)->gso_size != ring->tx.cur_mss) {
 135                         context_desc = 1;
 136                         pkt_info->desc_count++;
 137                 }
 138
 139                 /* TSO requires an extra descriptor for TSO header */
 140                 pkt_info->desc_count++;
 141
 142                 pkt_info->attributes = XLGMAC_SET_REG_BITS(
 143                                         pkt_info->attributes,
 144                                         TX_PACKET_ATTRIBUTES_TSO_ENABLE_POS,
 145                                         TX_PACKET_ATTRIBUTES_TSO_ENABLE_LEN,
 146                                         1);
 147                 pkt_info->attributes = XLGMAC_SET_REG_BITS(
 148                                         pkt_info->attributes,
 149                                         TX_PACKET_ATTRIBUTES_CSUM_ENABLE_POS,
 150                                         TX_PACKET_ATTRIBUTES_CSUM_ENABLE_LEN,
 151                                         1);
 152         } else if (skb->ip_summed == CHECKSUM_PARTIAL)
 153                 pkt_info->attributes = XLGMAC_SET_REG_BITS(
 154                                         pkt_info->attributes,
 155                                         TX_PACKET_ATTRIBUTES_CSUM_ENABLE_POS,
 156                                         TX_PACKET_ATTRIBUTES_CSUM_ENABLE_LEN,
 157                                         1);
 158
 159         if (skb_vlan_tag_present(skb)) {
 160                 /* VLAN requires an extra descriptor if tag is different */
 161                 if (skb_vlan_tag_get(skb) != ring->tx.cur_vlan_ctag)
 162                         /* We can share with the TSO context descriptor */
 163                         if (!context_desc) {
 164                                 context_desc = 1;
 165                                 pkt_info->desc_count++;
 166                         }
 167
 168                 pkt_info->attributes = XLGMAC_SET_REG_BITS(
 169                                         pkt_info->attributes,
 170                                         TX_PACKET_ATTRIBUTES_VLAN_CTAG_POS,
 171                                         TX_PACKET_ATTRIBUTES_VLAN_CTAG_LEN,
 172                                         1);
 173         }
 174
 175         for (len = skb_headlen(skb); len;) {
 176                 pkt_info->desc_count++;
 177                 len -= min_t(unsigned int, len, XLGMAC_TX_MAX_BUF_SIZE);
 178         }
 179
 180         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 181                 frag = &skb_shinfo(skb)->frags[i];
 182                 for (len = skb_frag_size(frag); len; ) {
 183                         pkt_info->desc_count++;
 184                         len -= min_t(unsigned int, len, XLGMAC_TX_MAX_BUF_SIZE);
 185                 }
 186         }
 187 }
 188
 189 static int xlgmac_calc_rx_buf_size(struct net_device *netdev, unsigned int mtu)
 190 {
 191         unsigned int rx_buf_size;
 192
 193         if (mtu > XLGMAC_JUMBO_PACKET_MTU) {
 194                 netdev_alert(netdev, "MTU exceeds maximum supported value\n");
 195                 return -EINVAL;
 196         }
 197
 198         rx_buf_size = mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
 199         rx_buf_size = clamp_val(rx_buf_size, XLGMAC_RX_MIN_BUF_SIZE, PAGE_SIZE);
 200
 201         rx_buf_size = (rx_buf_size + XLGMAC_RX_BUF_ALIGN - 1) &
 202                       ~(XLGMAC_RX_BUF_ALIGN - 1);
 203
 204         return rx_buf_size;
 205 }
 206
 207 static void xlgmac_enable_rx_tx_ints(struct xlgmac_pdata *pdata)
 208 {
 209         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 210         struct xlgmac_channel *channel;
 211         enum xlgmac_int int_id;
 212         unsigned int i;
 213
 214         channel = pdata->channel_head;
 215         for (i = 0; i < pdata->channel_count; i++, channel++) {
 216                 if (channel->tx_ring && channel->rx_ring)
 217                         int_id = XLGMAC_INT_DMA_CH_SR_TI_RI;
 218                 else if (channel->tx_ring)
 219                         int_id = XLGMAC_INT_DMA_CH_SR_TI;
 220                 else if (channel->rx_ring)
 221                         int_id = XLGMAC_INT_DMA_CH_SR_RI;
 222                 else
 223                         continue;
 224
 225                 hw_ops->enable_int(channel, int_id);
 226         }
 227 }
 228
 229 static void xlgmac_disable_rx_tx_ints(struct xlgmac_pdata *pdata)
 230 {
 231         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 232         struct xlgmac_channel *channel;
 233         enum xlgmac_int int_id;
 234         unsigned int i;
 235
 236         channel = pdata->channel_head;
 237         for (i = 0; i < pdata->channel_count; i++, channel++) {
 238                 if (channel->tx_ring && channel->rx_ring)
 239                         int_id = XLGMAC_INT_DMA_CH_SR_TI_RI;
 240                 else if (channel->tx_ring)
 241                         int_id = XLGMAC_INT_DMA_CH_SR_TI;
 242                 else if (channel->rx_ring)
 243                         int_id = XLGMAC_INT_DMA_CH_SR_RI;
 244                 else
 245                         continue;
 246
 247                 hw_ops->disable_int(channel, int_id);
 248         }
 249 }
 250
 251 static irqreturn_t xlgmac_isr(int irq, void *data)
 252 {
 253         unsigned int dma_isr, dma_ch_isr, mac_isr;
 254         struct xlgmac_pdata *pdata = data;
 255         struct xlgmac_channel *channel;
 256         struct xlgmac_hw_ops *hw_ops;
 257         unsigned int i, ti, ri;
 258
 259         hw_ops = &pdata->hw_ops;
 260
 261         /* The DMA interrupt status register also reports MAC and MTL
 262          * interrupts. So for polling mode, we just need to check for
 263          * this register to be non-zero
 264          */
 265         dma_isr = readl(pdata->mac_regs + DMA_ISR);
 266         if (!dma_isr)
 267                 return IRQ_HANDLED;
 268
 269         netif_dbg(pdata, intr, pdata->netdev, "DMA_ISR=%#010x\n", dma_isr);
 270
 271         for (i = 0; i < pdata->channel_count; i++) {
 272                 if (!(dma_isr & (1 << i)))
 273                         continue;
 274
 275                 channel = pdata->channel_head + i;
 276
 277                 dma_ch_isr = readl(XLGMAC_DMA_REG(channel, DMA_CH_SR));
 278                 netif_dbg(pdata, intr, pdata->netdev, "DMA_CH%u_ISR=%#010x\n",
 279                           i, dma_ch_isr);
 280
 281                 /* The TI or RI interrupt bits may still be set even if using
 282                  * per channel DMA interrupts. Check to be sure those are not
 283                  * enabled before using the private data napi structure.
 284                  */
 285                 ti = XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TI_POS,
 286                                          DMA_CH_SR_TI_LEN);
 287                 ri = XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RI_POS,
 288                                          DMA_CH_SR_RI_LEN);
 289                 if (!pdata->per_channel_irq && (ti || ri)) {
 290                         if (napi_schedule_prep(&pdata->napi)) {
 291                                 /* Disable Tx and Rx interrupts */
 292                                 xlgmac_disable_rx_tx_ints(pdata);
 293
 294                                 pdata->stats.napi_poll_isr++;
 295                                 /* Turn on polling */
 296                                 __napi_schedule_irqoff(&pdata->napi);
 297                         }
 298                 }
 299
 300                 if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TPS_POS,
 301                                         DMA_CH_SR_TPS_LEN))
 302                         pdata->stats.tx_process_stopped++;
 303
 304                 if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RPS_POS,
 305                                         DMA_CH_SR_RPS_LEN))
 306                         pdata->stats.rx_process_stopped++;
 307
 308                 if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TBU_POS,
 309                                         DMA_CH_SR_TBU_LEN))
 310                         pdata->stats.tx_buffer_unavailable++;
 311
 312                 if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RBU_POS,
 313                                         DMA_CH_SR_RBU_LEN))
 314                         pdata->stats.rx_buffer_unavailable++;
 315
 316                 /* Restart the device on a Fatal Bus Error */
 317                 if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_FBE_POS,
 318                                         DMA_CH_SR_FBE_LEN)) {
 319                         pdata->stats.fatal_bus_error++;
 320                         schedule_work(&pdata->restart_work);
 321                 }
 322
 323                 /* Clear all interrupt signals */
 324                 writel(dma_ch_isr, XLGMAC_DMA_REG(channel, DMA_CH_SR));
 325         }
 326
 327         if (XLGMAC_GET_REG_BITS(dma_isr, DMA_ISR_MACIS_POS,
 328                                 DMA_ISR_MACIS_LEN)) {
 329                 mac_isr = readl(pdata->mac_regs + MAC_ISR);
 330
 331                 if (XLGMAC_GET_REG_BITS(mac_isr, MAC_ISR_MMCTXIS_POS,
 332                                         MAC_ISR_MMCTXIS_LEN))
 333                         hw_ops->tx_mmc_int(pdata);
 334
 335                 if (XLGMAC_GET_REG_BITS(mac_isr, MAC_ISR_MMCRXIS_POS,
 336                                         MAC_ISR_MMCRXIS_LEN))
 337                         hw_ops->rx_mmc_int(pdata);
 338         }
 339
 340         return IRQ_HANDLED;
 341 }
 342
 343 static irqreturn_t xlgmac_dma_isr(int irq, void *data)
 344 {
 345         struct xlgmac_channel *channel = data;
 346
 347         /* Per channel DMA interrupts are enabled, so we use the per
 348          * channel napi structure and not the private data napi structure
 349          */
 350         if (napi_schedule_prep(&channel->napi)) {
 351                 /* Disable Tx and Rx interrupts */
 352                 disable_irq_nosync(channel->dma_irq);
 353
 354                 /* Turn on polling */
 355                 __napi_schedule_irqoff(&channel->napi);
 356         }
 357
 358         return IRQ_HANDLED;
 359 }
 360
 361 static void xlgmac_tx_timer(unsigned long data)
 362 {
 363         struct xlgmac_channel *channel = (struct xlgmac_channel *)data;
 364         struct xlgmac_pdata *pdata = channel->pdata;
 365         struct napi_struct *napi;
 366
 367         napi = (pdata->per_channel_irq) ? &channel->napi : &pdata->napi;
 368
 369         if (napi_schedule_prep(napi)) {
 370                 /* Disable Tx and Rx interrupts */
 371                 if (pdata->per_channel_irq)
 372                         disable_irq_nosync(channel->dma_irq);
 373                 else
 374                         xlgmac_disable_rx_tx_ints(pdata);
 375
 376                 pdata->stats.napi_poll_txtimer++;
 377                 /* Turn on polling */
 378                 __napi_schedule(napi);
 379         }
 380
 381         channel->tx_timer_active = 0;
 382 }
 383
 384 static void xlgmac_init_timers(struct xlgmac_pdata *pdata)
 385 {
 386         struct xlgmac_channel *channel;
 387         unsigned int i;
 388
 389         channel = pdata->channel_head;
 390         for (i = 0; i < pdata->channel_count; i++, channel++) {
 391                 if (!channel->tx_ring)
 392                         break;
 393
 394                 setup_timer(&channel->tx_timer, xlgmac_tx_timer,
 395                             (unsigned long)channel);
 396         }
 397 }
 398
 399 static void xlgmac_stop_timers(struct xlgmac_pdata *pdata)
 400 {
 401         struct xlgmac_channel *channel;
 402         unsigned int i;
 403
 404         channel = pdata->channel_head;
 405         for (i = 0; i < pdata->channel_count; i++, channel++) {
 406                 if (!channel->tx_ring)
 407                         break;
 408
 409                 del_timer_sync(&channel->tx_timer);
 410         }
 411 }
 412
 413 static void xlgmac_napi_enable(struct xlgmac_pdata *pdata, unsigned int add)
 414 {
 415         struct xlgmac_channel *channel;
 416         unsigned int i;
 417
 418         if (pdata->per_channel_irq) {
 419                 channel = pdata->channel_head;
 420                 for (i = 0; i < pdata->channel_count; i++, channel++) {
 421                         if (add)
 422                                 netif_napi_add(pdata->netdev, &channel->napi,
 423                                                xlgmac_one_poll,
 424                                                NAPI_POLL_WEIGHT);
 425
 426                         napi_enable(&channel->napi);
 427                 }
 428         } else {
 429                 if (add)
 430                         netif_napi_add(pdata->netdev, &pdata->napi,
 431                                        xlgmac_all_poll, NAPI_POLL_WEIGHT);
 432
 433                 napi_enable(&pdata->napi);
 434         }
 435 }
 436
 437 static void xlgmac_napi_disable(struct xlgmac_pdata *pdata, unsigned int del)
 438 {
 439         struct xlgmac_channel *channel;
 440         unsigned int i;
 441
 442         if (pdata->per_channel_irq) {
 443                 channel = pdata->channel_head;
 444                 for (i = 0; i < pdata->channel_count; i++, channel++) {
 445                         napi_disable(&channel->napi);
 446
 447                         if (del)
 448                                 netif_napi_del(&channel->napi);
 449                 }
 450         } else {
 451                 napi_disable(&pdata->napi);
 452
 453                 if (del)
 454                         netif_napi_del(&pdata->napi);
 455         }
 456 }
 457
 458 static int xlgmac_request_irqs(struct xlgmac_pdata *pdata)
 459 {
 460         struct net_device *netdev = pdata->netdev;
 461         struct xlgmac_channel *channel;
 462         unsigned int i;
 463         int ret;
 464
 465         ret = devm_request_irq(pdata->dev, pdata->dev_irq, xlgmac_isr,
 466                                IRQF_SHARED, netdev->name, pdata);
 467         if (ret) {
 468                 netdev_alert(netdev, "error requesting irq %d\n",
 469                              pdata->dev_irq);
 470                 return ret;
 471         }
 472
 473         if (!pdata->per_channel_irq)
 474                 return 0;
 475
 476         channel = pdata->channel_head;
 477         for (i = 0; i < pdata->channel_count; i++, channel++) {
 478                 snprintf(channel->dma_irq_name,
 479                          sizeof(channel->dma_irq_name) - 1,
 480                          "%s-TxRx-%u", netdev_name(netdev),
 481                          channel->queue_index);
 482
 483                 ret = devm_request_irq(pdata->dev, channel->dma_irq,
 484                                        xlgmac_dma_isr, 0,
 485                                        channel->dma_irq_name, channel);
 486                 if (ret) {
 487                         netdev_alert(netdev, "error requesting irq %d\n",
 488                                      channel->dma_irq);
 489                         goto err_irq;
 490                 }
 491         }
 492
 493         return 0;
 494
 495 err_irq:
 496         /* Using an unsigned int, 'i' will go to UINT_MAX and exit */
 497         for (i--, channel--; i < pdata->channel_count; i--, channel--)
 498                 devm_free_irq(pdata->dev, channel->dma_irq, channel);
 499
 500         devm_free_irq(pdata->dev, pdata->dev_irq, pdata);
 501
 502         return ret;
 503 }
 504
 505 static void xlgmac_free_irqs(struct xlgmac_pdata *pdata)
 506 {
 507         struct xlgmac_channel *channel;
 508         unsigned int i;
 509
 510         devm_free_irq(pdata->dev, pdata->dev_irq, pdata);
 511
 512         if (!pdata->per_channel_irq)
 513                 return;
 514
 515         channel = pdata->channel_head;
 516         for (i = 0; i < pdata->channel_count; i++, channel++)
 517                 devm_free_irq(pdata->dev, channel->dma_irq, channel);
 518 }
 519
 520 static void xlgmac_free_tx_data(struct xlgmac_pdata *pdata)
 521 {
 522         struct xlgmac_desc_ops *desc_ops = &pdata->desc_ops;
 523         struct xlgmac_desc_data *desc_data;
 524         struct xlgmac_channel *channel;
 525         struct xlgmac_ring *ring;
 526         unsigned int i, j;
 527
 528         channel = pdata->channel_head;
 529         for (i = 0; i < pdata->channel_count; i++, channel++) {
 530                 ring = channel->tx_ring;
 531                 if (!ring)
 532                         break;
 533
 534                 for (j = 0; j < ring->dma_desc_count; j++) {
 535                         desc_data = XLGMAC_GET_DESC_DATA(ring, j);
 536                         desc_ops->unmap_desc_data(pdata, desc_data);
 537                 }
 538         }
 539 }
 540
 541 static void xlgmac_free_rx_data(struct xlgmac_pdata *pdata)
 542 {
 543         struct xlgmac_desc_ops *desc_ops = &pdata->desc_ops;
 544         struct xlgmac_desc_data *desc_data;
 545         struct xlgmac_channel *channel;
 546         struct xlgmac_ring *ring;
 547         unsigned int i, j;
 548
 549         channel = pdata->channel_head;
 550         for (i = 0; i < pdata->channel_count; i++, channel++) {
 551                 ring = channel->rx_ring;
 552                 if (!ring)
 553                         break;
 554
 555                 for (j = 0; j < ring->dma_desc_count; j++) {
 556                         desc_data = XLGMAC_GET_DESC_DATA(ring, j);
 557                         desc_ops->unmap_desc_data(pdata, desc_data);
 558                 }
 559         }
 560 }
 561
 562 static int xlgmac_start(struct xlgmac_pdata *pdata)
 563 {
 564         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 565         struct net_device *netdev = pdata->netdev;
 566         int ret;
 567
 568         hw_ops->init(pdata);
 569         xlgmac_napi_enable(pdata, 1);
 570
 571         ret = xlgmac_request_irqs(pdata);
 572         if (ret)
 573                 goto err_napi;
 574
 575         hw_ops->enable_tx(pdata);
 576         hw_ops->enable_rx(pdata);
 577         netif_tx_start_all_queues(netdev);
 578
 579         return 0;
 580
 581 err_napi:
 582         xlgmac_napi_disable(pdata, 1);
 583         hw_ops->exit(pdata);
 584
 585         return ret;
 586 }
 587
 588 static void xlgmac_stop(struct xlgmac_pdata *pdata)
 589 {
 590         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 591         struct net_device *netdev = pdata->netdev;
 592         struct xlgmac_channel *channel;
 593         struct netdev_queue *txq;
 594         unsigned int i;
 595
 596         netif_tx_stop_all_queues(netdev);
 597         xlgmac_stop_timers(pdata);
 598         hw_ops->disable_tx(pdata);
 599         hw_ops->disable_rx(pdata);
 600         xlgmac_free_irqs(pdata);
 601         xlgmac_napi_disable(pdata, 1);
 602         hw_ops->exit(pdata);
 603
 604         channel = pdata->channel_head;
 605         for (i = 0; i < pdata->channel_count; i++, channel++) {
 606                 if (!channel->tx_ring)
 607                         continue;
 608
 609                 txq = netdev_get_tx_queue(netdev, channel->queue_index);
 610                 netdev_tx_reset_queue(txq);
 611         }
 612 }
 613
 614 static void xlgmac_restart_dev(struct xlgmac_pdata *pdata)
 615 {
 616         /* If not running, "restart" will happen on open */
 617         if (!netif_running(pdata->netdev))
 618                 return;
 619
 620         xlgmac_stop(pdata);
 621
 622         xlgmac_free_tx_data(pdata);
 623         xlgmac_free_rx_data(pdata);
 624
 625         xlgmac_start(pdata);
 626 }
 627
 628 static void xlgmac_restart(struct work_struct *work)
 629 {
 630         struct xlgmac_pdata *pdata = container_of(work,
 631                                                    struct xlgmac_pdata,
 632                                                    restart_work);
 633
 634         rtnl_lock();
 635
 636         xlgmac_restart_dev(pdata);
 637
 638         rtnl_unlock();
 639 }
 640
 641 static int xlgmac_open(struct net_device *netdev)
 642 {
 643         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 644         struct xlgmac_desc_ops *desc_ops;
 645         int ret;
 646
 647         desc_ops = &pdata->desc_ops;
 648
 649         /* TODO: Initialize the phy */
 650
 651         /* Calculate the Rx buffer size before allocating rings */
 652         ret = xlgmac_calc_rx_buf_size(netdev, netdev->mtu);
 653         if (ret < 0)
 654                 return ret;
 655         pdata->rx_buf_size = ret;
 656
 657         /* Allocate the channels and rings */
 658         ret = desc_ops->alloc_channles_and_rings(pdata);
 659         if (ret)
 660                 return ret;
 661
 662         INIT_WORK(&pdata->restart_work, xlgmac_restart);
 663         xlgmac_init_timers(pdata);
 664
 665         ret = xlgmac_start(pdata);
 666         if (ret)
 667                 goto err_channels_and_rings;
 668
 669         return 0;
 670
 671 err_channels_and_rings:
 672         desc_ops->free_channels_and_rings(pdata);
 673
 674         return ret;
 675 }
 676
 677 static int xlgmac_close(struct net_device *netdev)
 678 {
 679         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 680         struct xlgmac_desc_ops *desc_ops;
 681
 682         desc_ops = &pdata->desc_ops;
 683
 684         /* Stop the device */
 685         xlgmac_stop(pdata);
 686
 687         /* Free the channels and rings */
 688         desc_ops->free_channels_and_rings(pdata);
 689
 690         return 0;
 691 }
 692
 693 static void xlgmac_tx_timeout(struct net_device *netdev)
 694 {
 695         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 696
 697         netdev_warn(netdev, "tx timeout, device restarting\n");
 698         schedule_work(&pdata->restart_work);
 699 }
 700
 701 static int xlgmac_xmit(struct sk_buff *skb, struct net_device *netdev)
 702 {
 703         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 704         struct xlgmac_pkt_info *tx_pkt_info;
 705         struct xlgmac_desc_ops *desc_ops;
 706         struct xlgmac_channel *channel;
 707         struct xlgmac_hw_ops *hw_ops;
 708         struct netdev_queue *txq;
 709         struct xlgmac_ring *ring;
 710         int ret;
 711
 712         desc_ops = &pdata->desc_ops;
 713         hw_ops = &pdata->hw_ops;
 714
 715         XLGMAC_PR("skb->len = %d\n", skb->len);
 716
 717         channel = pdata->channel_head + skb->queue_mapping;
 718         txq = netdev_get_tx_queue(netdev, channel->queue_index);
 719         ring = channel->tx_ring;
 720         tx_pkt_info = &ring->pkt_info;
 721
 722         if (skb->len == 0) {
 723                 netif_err(pdata, tx_err, netdev,
 724                           "empty skb received from stack\n");
 725                 dev_kfree_skb_any(skb);
 726                 return NETDEV_TX_OK;
 727         }
 728
 729         /* Prepare preliminary packet info for TX */
 730         memset(tx_pkt_info, 0, sizeof(*tx_pkt_info));
 731         xlgmac_prep_tx_pkt(pdata, ring, skb, tx_pkt_info);
 732
 733         /* Check that there are enough descriptors available */
 734         ret = xlgmac_maybe_stop_tx_queue(channel, ring,
 735                                          tx_pkt_info->desc_count);
 736         if (ret)
 737                 return ret;
 738
 739         ret = xlgmac_prep_tso(skb, tx_pkt_info);
 740         if (ret) {
 741                 netif_err(pdata, tx_err, netdev,
 742                           "error processing TSO packet\n");
 743                 dev_kfree_skb_any(skb);
 744                 return ret;
 745         }
 746         xlgmac_prep_vlan(skb, tx_pkt_info);
 747
 748         if (!desc_ops->map_tx_skb(channel, skb)) {
 749                 dev_kfree_skb_any(skb);
 750                 return NETDEV_TX_OK;
 751         }
 752
 753         /* Report on the actual number of bytes (to be) sent */
 754         netdev_tx_sent_queue(txq, tx_pkt_info->tx_bytes);
 755
 756         /* Configure required descriptor fields for transmission */
 757         hw_ops->dev_xmit(channel);
 758
 759         if (netif_msg_pktdata(pdata))
 760                 xlgmac_print_pkt(netdev, skb, true);
 761
 762         /* Stop the queue in advance if there may not be enough descriptors */
 763         xlgmac_maybe_stop_tx_queue(channel, ring, XLGMAC_TX_MAX_DESC_NR);
 764
 765         return NETDEV_TX_OK;
 766 }
 767
 768 static void xlgmac_get_stats64(struct net_device *netdev,
 769                                struct rtnl_link_stats64 *s)
 770 {
 771         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 772         struct xlgmac_stats *pstats = &pdata->stats;
 773
 774         pdata->hw_ops.read_mmc_stats(pdata);
 775
 776         s->rx_packets = pstats->rxframecount_gb;
 777         s->rx_bytes = pstats->rxoctetcount_gb;
 778         s->rx_errors = pstats->rxframecount_gb -
 779                        pstats->rxbroadcastframes_g -
 780                        pstats->rxmulticastframes_g -
 781                        pstats->rxunicastframes_g;
 782         s->multicast = pstats->rxmulticastframes_g;
 783         s->rx_length_errors = pstats->rxlengtherror;
 784         s->rx_crc_errors = pstats->rxcrcerror;
 785         s->rx_fifo_errors = pstats->rxfifooverflow;
 786
 787         s->tx_packets = pstats->txframecount_gb;
 788         s->tx_bytes = pstats->txoctetcount_gb;
 789         s->tx_errors = pstats->txframecount_gb - pstats->txframecount_g;
 790         s->tx_dropped = netdev->stats.tx_dropped;
 791 }
 792
 793 static int xlgmac_set_mac_address(struct net_device *netdev, void *addr)
 794 {
 795         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 796         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 797         struct sockaddr *saddr = addr;
 798
 799         if (!is_valid_ether_addr(saddr->sa_data))
 800                 return -EADDRNOTAVAIL;
 801
 802         memcpy(netdev->dev_addr, saddr->sa_data, netdev->addr_len);
 803
 804         hw_ops->set_mac_address(pdata, netdev->dev_addr);
 805
 806         return 0;
 807 }
 808
 809 static int xlgmac_ioctl(struct net_device *netdev,
 810                         struct ifreq *ifreq, int cmd)
 811 {
 812         if (!netif_running(netdev))
 813                 return -ENODEV;
 814
 815         return 0;
 816 }
 817
 818 static int xlgmac_change_mtu(struct net_device *netdev, int mtu)
 819 {
 820         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 821         int ret;
 822
 823         ret = xlgmac_calc_rx_buf_size(netdev, mtu);
 824         if (ret < 0)
 825                 return ret;
 826
 827         pdata->rx_buf_size = ret;
 828         netdev->mtu = mtu;
 829
 830         xlgmac_restart_dev(pdata);
 831
 832         return 0;
 833 }
 834
 835 static int xlgmac_vlan_rx_add_vid(struct net_device *netdev,
 836                                   __be16 proto,
 837                                   u16 vid)
 838 {
 839         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 840         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 841
 842         set_bit(vid, pdata->active_vlans);
 843         hw_ops->update_vlan_hash_table(pdata);
 844
 845         return 0;
 846 }
 847
 848 static int xlgmac_vlan_rx_kill_vid(struct net_device *netdev,
 849                                    __be16 proto,
 850                                    u16 vid)
 851 {
 852         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 853         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 854
 855         clear_bit(vid, pdata->active_vlans);
 856         hw_ops->update_vlan_hash_table(pdata);
 857
 858         return 0;
 859 }
 860
 861 #ifdef CONFIG_NET_POLL_CONTROLLER
 862 static void xlgmac_poll_controller(struct net_device *netdev)
 863 {
 864         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 865         struct xlgmac_channel *channel;
 866         unsigned int i;
 867
 868         if (pdata->per_channel_irq) {
 869                 channel = pdata->channel_head;
 870                 for (i = 0; i < pdata->channel_count; i++, channel++)
 871                         xlgmac_dma_isr(channel->dma_irq, channel);
 872         } else {
 873                 disable_irq(pdata->dev_irq);
 874                 xlgmac_isr(pdata->dev_irq, pdata);
 875                 enable_irq(pdata->dev_irq);
 876         }
 877 }
 878 #endif /* CONFIG_NET_POLL_CONTROLLER */
 879
 880 static int xlgmac_set_features(struct net_device *netdev,
 881                                netdev_features_t features)
 882 {
 883         netdev_features_t rxhash, rxcsum, rxvlan, rxvlan_filter;
 884         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 885         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 886         int ret = 0;
 887
 888         rxhash = pdata->netdev_features & NETIF_F_RXHASH;
 889         rxcsum = pdata->netdev_features & NETIF_F_RXCSUM;
 890         rxvlan = pdata->netdev_features & NETIF_F_HW_VLAN_CTAG_RX;
 891         rxvlan_filter = pdata->netdev_features & NETIF_F_HW_VLAN_CTAG_FILTER;
 892
 893         if ((features & NETIF_F_RXHASH) && !rxhash)
 894                 ret = hw_ops->enable_rss(pdata);
 895         else if (!(features & NETIF_F_RXHASH) && rxhash)
 896                 ret = hw_ops->disable_rss(pdata);
 897         if (ret)
 898                 return ret;
 899
 900         if ((features & NETIF_F_RXCSUM) && !rxcsum)
 901                 hw_ops->enable_rx_csum(pdata);
 902         else if (!(features & NETIF_F_RXCSUM) && rxcsum)
 903                 hw_ops->disable_rx_csum(pdata);
 904
 905         if ((features & NETIF_F_HW_VLAN_CTAG_RX) && !rxvlan)
 906                 hw_ops->enable_rx_vlan_stripping(pdata);
 907         else if (!(features & NETIF_F_HW_VLAN_CTAG_RX) && rxvlan)
 908                 hw_ops->disable_rx_vlan_stripping(pdata);
 909
 910         if ((features & NETIF_F_HW_VLAN_CTAG_FILTER) && !rxvlan_filter)
 911                 hw_ops->enable_rx_vlan_filtering(pdata);
 912         else if (!(features & NETIF_F_HW_VLAN_CTAG_FILTER) && rxvlan_filter)
 913                 hw_ops->disable_rx_vlan_filtering(pdata);
 914
 915         pdata->netdev_features = features;
 916
 917         return 0;
 918 }
 919
 920 static void xlgmac_set_rx_mode(struct net_device *netdev)
 921 {
 922         struct xlgmac_pdata *pdata = netdev_priv(netdev);
 923         struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
 924
 925         hw_ops->config_rx_mode(pdata);
 926 }
 927
 928 static const struct net_device_ops xlgmac_netdev_ops = {
 929         .ndo_open               = xlgmac_open,
 930         .ndo_stop               = xlgmac_close,
 931         .ndo_start_xmit         = xlgmac_xmit,
 932         .ndo_tx_timeout         = xlgmac_tx_timeout,
 933         .ndo_get_stats64        = xlgmac_get_stats64,
 934         .ndo_change_mtu         = xlgmac_change_mtu,
 935         .ndo_set_mac_address    = xlgmac_set_mac_address,
 936         .ndo_validate_addr      = eth_validate_addr,
 937         .ndo_do_ioctl           = xlgmac_ioctl,
 938         .ndo_vlan_rx_add_vid    = xlgmac_vlan_rx_add_vid,
 939         .ndo_vlan_rx_kill_vid   = xlgmac_vlan_rx_kill_vid,
 940 #ifdef CONFIG_NET_POLL_CONTROLLER
 941         .ndo_poll_controller    = xlgmac_poll_controller,
 942 #endif
 943         .ndo_set_features       = xlgmac_set_features,
 944         .ndo_set_rx_mode        = xlgmac_set_rx_mode,
 945 };
 946
 947 const struct net_device_ops *xlgmac_get_netdev_ops(void)
 948 {
 949         return &xlgmac_netdev_ops;
 950 }
 951
 952 static void xlgmac_rx_refresh(struct xlgmac_channel *channel)
 953 {
 954         struct xlgmac_pdata *pdata = channel->pdata;
 955         struct xlgmac_ring *ring = channel->rx_ring;
 956         struct xlgmac_desc_data *desc_data;
 957         struct xlgmac_desc_ops *desc_ops;
 958         struct xlgmac_hw_ops *hw_ops;
 959
 960         desc_ops = &pdata->desc_ops;
 961         hw_ops = &pdata->hw_ops;
 962
 963         while (ring->dirty != ring->cur) {
 964                 desc_data = XLGMAC_GET_DESC_DATA(ring, ring->dirty);
 965
 966                 /* Reset desc_data values */
 967                 desc_ops->unmap_desc_data(pdata, desc_data);
 968
 969                 if (desc_ops->map_rx_buffer(pdata, ring, desc_data))
 970                         break;
 971
 972                 hw_ops->rx_desc_reset(pdata, desc_data, ring->dirty);
 973
 974                 ring->dirty++;
 975         }
 976
 977         /* Make sure everything is written before the register write */
 978         wmb();
 979
 980         /* Update the Rx Tail Pointer Register with address of
 981          * the last cleaned entry
 982          */
 983         desc_data = XLGMAC_GET_DESC_DATA(ring, ring->dirty - 1);
 984         writel(lower_32_bits(desc_data->dma_desc_addr),
 985                XLGMAC_DMA_REG(channel, DMA_CH_RDTR_LO));
 986 }
 987
 988 static struct sk_buff *xlgmac_create_skb(struct xlgmac_pdata *pdata,
 989                                          struct napi_struct *napi,
 990                                          struct xlgmac_desc_data *desc_data,
 991                                          unsigned int len)
 992 {
 993         unsigned int copy_len;
 994         struct sk_buff *skb;
 995         u8 *packet;
 996
 997         skb = napi_alloc_skb(napi, desc_data->rx.hdr.dma_len);
 998         if (!skb)
 999                 return NULL;
1000
1001         /* Start with the header buffer which may contain just the header
1002          * or the header plus data
1003          */
1004         dma_sync_single_range_for_cpu(pdata->dev, desc_data->rx.hdr.dma_base,
1005                                       desc_data->rx.hdr.dma_off,
1006                                       desc_data->rx.hdr.dma_len,
1007                                       DMA_FROM_DEVICE);
1008
1009         packet = page_address(desc_data->rx.hdr.pa.pages) +
1010                  desc_data->rx.hdr.pa.pages_offset;
1011         copy_len = (desc_data->rx.hdr_len) ? desc_data->rx.hdr_len : len;
1012         copy_len = min(desc_data->rx.hdr.dma_len, copy_len);
1013         skb_copy_to_linear_data(skb, packet, copy_len);
1014         skb_put(skb, copy_len);
1015
1016         len -= copy_len;
1017         if (len) {
1018                 /* Add the remaining data as a frag */
1019                 dma_sync_single_range_for_cpu(pdata->dev,
1020                                               desc_data->rx.buf.dma_base,
1021                                               desc_data->rx.buf.dma_off,
1022                                               desc_data->rx.buf.dma_len,
1023                                               DMA_FROM_DEVICE);
1024
1025                 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
1026                                 desc_data->rx.buf.pa.pages,
1027                                 desc_data->rx.buf.pa.pages_offset,
1028                                 len, desc_data->rx.buf.dma_len);
1029                 desc_data->rx.buf.pa.pages = NULL;
1030         }
1031
1032         return skb;
1033 }
1034
1035 static int xlgmac_tx_poll(struct xlgmac_channel *channel)
1036 {
1037         struct xlgmac_pdata *pdata = channel->pdata;
1038         struct xlgmac_ring *ring = channel->tx_ring;
1039         struct net_device *netdev = pdata->netdev;
1040         unsigned int tx_packets = 0, tx_bytes = 0;
1041         struct xlgmac_desc_data *desc_data;
1042         struct xlgmac_dma_desc *dma_desc;
1043         struct xlgmac_desc_ops *desc_ops;
1044         struct xlgmac_hw_ops *hw_ops;
1045         struct netdev_queue *txq;
1046         int processed = 0;
1047         unsigned int cur;
1048
1049         desc_ops = &pdata->desc_ops;
1050         hw_ops = &pdata->hw_ops;
1051
1052         /* Nothing to do if there isn't a Tx ring for this channel */
1053         if (!ring)
1054                 return 0;
1055
1056         cur = ring->cur;
1057
1058         /* Be sure we get ring->cur before accessing descriptor data */
1059         smp_rmb();
1060
1061         txq = netdev_get_tx_queue(netdev, channel->queue_index);
1062
1063         while ((processed < XLGMAC_TX_DESC_MAX_PROC) &&
1064                (ring->dirty != cur)) {
1065                 desc_data = XLGMAC_GET_DESC_DATA(ring, ring->dirty);
1066                 dma_desc = desc_data->dma_desc;
1067
1068                 if (!hw_ops->tx_complete(dma_desc))
1069                         break;
1070
1071                 /* Make sure descriptor fields are read after reading
1072                  * the OWN bit
1073                  */
1074                 dma_rmb();
1075
1076                 if (netif_msg_tx_done(pdata))
1077                         xlgmac_dump_tx_desc(pdata, ring, ring->dirty, 1, 0);
1078
1079                 if (hw_ops->is_last_desc(dma_desc)) {
1080                         tx_packets += desc_data->tx.packets;
1081                         tx_bytes += desc_data->tx.bytes;
1082                 }
1083
1084                 /* Free the SKB and reset the descriptor for re-use */
1085                 desc_ops->unmap_desc_data(pdata, desc_data);
1086                 hw_ops->tx_desc_reset(desc_data);
1087
1088                 processed++;
1089                 ring->dirty++;
1090         }
1091
1092         if (!processed)
1093                 return 0;
1094
1095         netdev_tx_completed_queue(txq, tx_packets, tx_bytes);
1096
1097         if ((ring->tx.queue_stopped == 1) &&
1098             (xlgmac_tx_avail_desc(ring) > XLGMAC_TX_DESC_MIN_FREE)) {
1099                 ring->tx.queue_stopped = 0;
1100                 netif_tx_wake_queue(txq);
1101         }
1102
1103         XLGMAC_PR("processed=%d\n", processed);
1104
1105         return processed;
1106 }
1107
1108 static int xlgmac_rx_poll(struct xlgmac_channel *channel, int budget)
1109 {
1110         struct xlgmac_pdata *pdata = channel->pdata;
1111         struct xlgmac_ring *ring = channel->rx_ring;
1112         struct net_device *netdev = pdata->netdev;
1113         unsigned int len, dma_desc_len, max_len;
1114         unsigned int context_next, context;
1115         struct xlgmac_desc_data *desc_data;
1116         struct xlgmac_pkt_info *pkt_info;
1117         unsigned int incomplete, error;
1118         struct xlgmac_hw_ops *hw_ops;
1119         unsigned int received = 0;
1120         struct napi_struct *napi;
1121         struct sk_buff *skb;
1122         int packet_count = 0;
1123
1124         hw_ops = &pdata->hw_ops;
1125
1126         /* Nothing to do if there isn't a Rx ring for this channel */
1127         if (!ring)
1128                 return 0;
1129
1130         incomplete = 0;
1131         context_next = 0;
1132
1133         napi = (pdata->per_channel_irq) ? &channel->napi : &pdata->napi;
1134
1135         desc_data = XLGMAC_GET_DESC_DATA(ring, ring->cur);
1136         pkt_info = &ring->pkt_info;
1137         while (packet_count < budget) {
1138                 /* First time in loop see if we need to restore state */
1139                 if (!received && desc_data->state_saved) {
1140                         skb = desc_data->state.skb;
1141                         error = desc_data->state.error;
1142                         len = desc_data->state.len;
1143                 } else {
1144                         memset(pkt_info, 0, sizeof(*pkt_info));
1145                         skb = NULL;
1146                         error = 0;
1147                         len = 0;
1148                 }
1149
1150 read_again:
1151                 desc_data = XLGMAC_GET_DESC_DATA(ring, ring->cur);
1152
1153                 if (xlgmac_rx_dirty_desc(ring) > XLGMAC_RX_DESC_MAX_DIRTY)
1154                         xlgmac_rx_refresh(channel);
1155
1156                 if (hw_ops->dev_read(channel))
1157                         break;
1158
1159                 received++;
1160                 ring->cur++;
1161
1162                 incomplete = XLGMAC_GET_REG_BITS(
1163                                         pkt_info->attributes,
1164                                         RX_PACKET_ATTRIBUTES_INCOMPLETE_POS,
1165                                         RX_PACKET_ATTRIBUTES_INCOMPLETE_LEN);
1166                 context_next = XLGMAC_GET_REG_BITS(
1167                                         pkt_info->attributes,
1168                                         RX_PACKET_ATTRIBUTES_CONTEXT_NEXT_POS,
1169                                         RX_PACKET_ATTRIBUTES_CONTEXT_NEXT_LEN);
1170                 context = XLGMAC_GET_REG_BITS(
1171                                         pkt_info->attributes,
1172                                         RX_PACKET_ATTRIBUTES_CONTEXT_POS,
1173                                         RX_PACKET_ATTRIBUTES_CONTEXT_LEN);
1174
1175                 /* Earlier error, just drain the remaining data */
1176                 if ((incomplete || context_next) && error)
1177                         goto read_again;
1178
1179                 if (error || pkt_info->errors) {
1180                         if (pkt_info->errors)
1181                                 netif_err(pdata, rx_err, netdev,
1182                                           "error in received packet\n");
1183                         dev_kfree_skb(skb);
1184                         goto next_packet;
1185                 }
1186
1187                 if (!context) {
1188                         /* Length is cumulative, get this descriptor's length */
1189                         dma_desc_len = desc_data->rx.len - len;
1190                         len += dma_desc_len;
1191
1192                         if (dma_desc_len && !skb) {
1193                                 skb = xlgmac_create_skb(pdata, napi, desc_data,
1194                                                         dma_desc_len);
1195                                 if (!skb)
1196                                         error = 1;
1197                         } else if (dma_desc_len) {
1198                                 dma_sync_single_range_for_cpu(
1199                                                 pdata->dev,
1200                                                 desc_data->rx.buf.dma_base,
1201                                                 desc_data->rx.buf.dma_off,
1202                                                 desc_data->rx.buf.dma_len,
1203                                                 DMA_FROM_DEVICE);
1204
1205                                 skb_add_rx_frag(
1206                                         skb, skb_shinfo(skb)->nr_frags,
1207                                         desc_data->rx.buf.pa.pages,
1208                                         desc_data->rx.buf.pa.pages_offset,
1209                                         dma_desc_len,
1210                                         desc_data->rx.buf.dma_len);
1211                                 desc_data->rx.buf.pa.pages = NULL;
1212                         }
1213                 }
1214
1215                 if (incomplete || context_next)
1216                         goto read_again;
1217
1218                 if (!skb)
1219                         goto next_packet;
1220
1221                 /* Be sure we don't exceed the configured MTU */
1222                 max_len = netdev->mtu + ETH_HLEN;
1223                 if (!(netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
1224                     (skb->protocol == htons(ETH_P_8021Q)))
1225                         max_len += VLAN_HLEN;
1226
1227                 if (skb->len > max_len) {
1228                         netif_err(pdata, rx_err, netdev,
1229                                   "packet length exceeds configured MTU\n");
1230                         dev_kfree_skb(skb);
1231                         goto next_packet;
1232                 }
1233
1234                 if (netif_msg_pktdata(pdata))
1235                         xlgmac_print_pkt(netdev, skb, false);
1236
1237                 skb_checksum_none_assert(skb);
1238                 if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
1239                                         RX_PACKET_ATTRIBUTES_CSUM_DONE_POS,
1240                                     RX_PACKET_ATTRIBUTES_CSUM_DONE_LEN))
1241                         skb->ip_summed = CHECKSUM_UNNECESSARY;
1242
1243                 if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
1244                                         RX_PACKET_ATTRIBUTES_VLAN_CTAG_POS,
1245                                     RX_PACKET_ATTRIBUTES_VLAN_CTAG_LEN)) {
1246                         __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
1247                                                pkt_info->vlan_ctag);
1248                         pdata->stats.rx_vlan_packets++;
1249                 }
1250
1251                 if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
1252                                         RX_PACKET_ATTRIBUTES_RSS_HASH_POS,
1253                                     RX_PACKET_ATTRIBUTES_RSS_HASH_LEN))
1254                         skb_set_hash(skb, pkt_info->rss_hash,
1255                                      pkt_info->rss_hash_type);
1256
1257                 skb->dev = netdev;
1258                 skb->protocol = eth_type_trans(skb, netdev);
1259                 skb_record_rx_queue(skb, channel->queue_index);
1260
1261                 napi_gro_receive(napi, skb);
1262
1263 next_packet:
1264                 packet_count++;
1265         }
1266
1267         /* Check if we need to save state before leaving */
1268         if (received && (incomplete || context_next)) {
1269                 desc_data = XLGMAC_GET_DESC_DATA(ring, ring->cur);
1270                 desc_data->state_saved = 1;
1271                 desc_data->state.skb = skb;
1272                 desc_data->state.len = len;
1273                 desc_data->state.error = error;
1274         }
1275
1276         XLGMAC_PR("packet_count = %d\n", packet_count);
1277
1278         return packet_count;
1279 }
1280
1281 static int xlgmac_one_poll(struct napi_struct *napi, int budget)
1282 {
1283         struct xlgmac_channel *channel = container_of(napi,
1284                                                 struct xlgmac_channel,
1285                                                 napi);
1286         int processed = 0;
1287
1288         XLGMAC_PR("budget=%d\n", budget);
1289
1290         /* Cleanup Tx ring first */
1291         xlgmac_tx_poll(channel);
1292
1293         /* Process Rx ring next */
1294         processed = xlgmac_rx_poll(channel, budget);
1295
1296         /* If we processed everything, we are done */
1297         if (processed < budget) {
1298                 /* Turn off polling */
1299                 napi_complete_done(napi, processed);
1300
1301                 /* Enable Tx and Rx interrupts */
1302                 enable_irq(channel->dma_irq);
1303         }
1304
1305         XLGMAC_PR("received = %d\n", processed);
1306
1307         return processed;
1308 }
1309
1310 static int xlgmac_all_poll(struct napi_struct *napi, int budget)
1311 {
1312         struct xlgmac_pdata *pdata = container_of(napi,
1313                                                    struct xlgmac_pdata,
1314                                                    napi);
1315         struct xlgmac_channel *channel;
1316         int processed, last_processed;
1317         int ring_budget;
1318         unsigned int i;
1319
1320         XLGMAC_PR("budget=%d\n", budget);
1321
1322         processed = 0;
1323         ring_budget = budget / pdata->rx_ring_count;
1324         do {
1325                 last_processed = processed;
1326
1327                 channel = pdata->channel_head;
1328                 for (i = 0; i < pdata->channel_count; i++, channel++) {
1329                         /* Cleanup Tx ring first */
1330                         xlgmac_tx_poll(channel);
1331
1332                         /* Process Rx ring next */
1333                         if (ring_budget > (budget - processed))
1334                                 ring_budget = budget - processed;
1335                         processed += xlgmac_rx_poll(channel, ring_budget);
1336                 }
1337         } while ((processed < budget) && (processed != last_processed));
1338
1339         /* If we processed everything, we are done */
1340         if (processed < budget) {
1341                 /* Turn off polling */
1342                 napi_complete_done(napi, processed);
1343
1344                 /* Enable Tx and Rx interrupts */
1345                 xlgmac_enable_rx_tx_ints(pdata);
1346         }
1347
1348         XLGMAC_PR("received = %d\n", processed);
1349
1350         return processed;
1351 }