drivers/net/ftmac100.c

   1 /*
   2  * Faraday FTMAC100 10/100 Ethernet
   3  *
   4  * (C) Copyright 2009-2011 Faraday Technology
   5  * Po-Yu Chuang <ratbert@faraday-tech.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  23
  24 #include <linux/dma-mapping.h>
  25 #include <linux/etherdevice.h>
  26 #include <linux/ethtool.h>
  27 #include <linux/init.h>
  28 #include <linux/io.h>
  29 #include <linux/mii.h>
  30 #include <linux/module.h>
  31 #include <linux/netdevice.h>
  32 #include <linux/platform_device.h>
  33
  34 #include "ftmac100.h"
  35
  36 #define DRV_NAME        "ftmac100"
  37 #define DRV_VERSION     "0.2"
  38
  39 #define RX_QUEUE_ENTRIES        128     /* must be power of 2 */
  40 #define TX_QUEUE_ENTRIES        16      /* must be power of 2 */
  41
  42 #define MAX_PKT_SIZE            1518
  43 #define RX_BUF_SIZE             2044    /* must be smaller than 0x7ff */
  44
  45 #if MAX_PKT_SIZE > 0x7ff
  46 #error invalid MAX_PKT_SIZE
  47 #endif
  48
  49 #if RX_BUF_SIZE > 0x7ff || RX_BUF_SIZE > PAGE_SIZE
  50 #error invalid RX_BUF_SIZE
  51 #endif
  52
  53 /******************************************************************************
  54  * private data
  55  *****************************************************************************/
  56 struct ftmac100_descs {
  57         struct ftmac100_rxdes rxdes[RX_QUEUE_ENTRIES];
  58         struct ftmac100_txdes txdes[TX_QUEUE_ENTRIES];
  59 };
  60
  61 struct ftmac100 {
  62         struct resource *res;
  63         void __iomem *base;
  64         int irq;
  65
  66         struct ftmac100_descs *descs;
  67         dma_addr_t descs_dma_addr;
  68
  69         unsigned int rx_pointer;
  70         unsigned int tx_clean_pointer;
  71         unsigned int tx_pointer;
  72         unsigned int tx_pending;
  73
  74         spinlock_t tx_lock;
  75
  76         struct net_device *netdev;
  77         struct device *dev;
  78         struct napi_struct napi;
  79
  80         struct mii_if_info mii;
  81 };
  82
  83 static int ftmac100_alloc_rx_page(struct ftmac100 *priv,
  84                                   struct ftmac100_rxdes *rxdes, gfp_t gfp);
  85
  86 /******************************************************************************
  87  * internal functions (hardware register access)
  88  *****************************************************************************/
  89 #define INT_MASK_ALL_ENABLED    (FTMAC100_INT_RPKT_FINISH       | \
  90                                  FTMAC100_INT_NORXBUF           | \
  91                                  FTMAC100_INT_XPKT_OK           | \
  92                                  FTMAC100_INT_XPKT_LOST         | \
  93                                  FTMAC100_INT_RPKT_LOST         | \
  94                                  FTMAC100_INT_AHB_ERR           | \
  95                                  FTMAC100_INT_PHYSTS_CHG)
  96
  97 #define INT_MASK_ALL_DISABLED   0
  98
  99 static void ftmac100_enable_all_int(struct ftmac100 *priv)
 100 {
 101         iowrite32(INT_MASK_ALL_ENABLED, priv->base + FTMAC100_OFFSET_IMR);
 102 }
 103
 104 static void ftmac100_disable_all_int(struct ftmac100 *priv)
 105 {
 106         iowrite32(INT_MASK_ALL_DISABLED, priv->base + FTMAC100_OFFSET_IMR);
 107 }
 108
 109 static void ftmac100_set_rx_ring_base(struct ftmac100 *priv, dma_addr_t addr)
 110 {
 111         iowrite32(addr, priv->base + FTMAC100_OFFSET_RXR_BADR);
 112 }
 113
 114 static void ftmac100_set_tx_ring_base(struct ftmac100 *priv, dma_addr_t addr)
 115 {
 116         iowrite32(addr, priv->base + FTMAC100_OFFSET_TXR_BADR);
 117 }
 118
 119 static void ftmac100_txdma_start_polling(struct ftmac100 *priv)
 120 {
 121         iowrite32(1, priv->base + FTMAC100_OFFSET_TXPD);
 122 }
 123
 124 static int ftmac100_reset(struct ftmac100 *priv)
 125 {
 126         struct net_device *netdev = priv->netdev;
 127         int i;
 128
 129         /* NOTE: reset clears all registers */
 130         iowrite32(FTMAC100_MACCR_SW_RST, priv->base + FTMAC100_OFFSET_MACCR);
 131
 132         for (i = 0; i < 5; i++) {
 133                 unsigned int maccr;
 134
 135                 maccr = ioread32(priv->base + FTMAC100_OFFSET_MACCR);
 136                 if (!(maccr & FTMAC100_MACCR_SW_RST)) {
 137                         /*
 138                          * FTMAC100_MACCR_SW_RST cleared does not indicate
 139                          * that hardware reset completed (what the f*ck).
 140                          * We still need to wait for a while.
 141                          */
 142                         udelay(500);
 143                         return 0;
 144                 }
 145
 146                 udelay(1000);
 147         }
 148
 149         netdev_err(netdev, "software reset failed\n");
 150         return -EIO;
 151 }
 152
 153 static void ftmac100_set_mac(struct ftmac100 *priv, const unsigned char *mac)
 154 {
 155         unsigned int maddr = mac[0] << 8 | mac[1];
 156         unsigned int laddr = mac[2] << 24 | mac[3] << 16 | mac[4] << 8 | mac[5];
 157
 158         iowrite32(maddr, priv->base + FTMAC100_OFFSET_MAC_MADR);
 159         iowrite32(laddr, priv->base + FTMAC100_OFFSET_MAC_LADR);
 160 }
 161
 162 #define MACCR_ENABLE_ALL        (FTMAC100_MACCR_XMT_EN  | \
 163                                  FTMAC100_MACCR_RCV_EN  | \
 164                                  FTMAC100_MACCR_XDMA_EN | \
 165                                  FTMAC100_MACCR_RDMA_EN | \
 166                                  FTMAC100_MACCR_CRC_APD | \
 167                                  FTMAC100_MACCR_FULLDUP | \
 168                                  FTMAC100_MACCR_RX_RUNT | \
 169                                  FTMAC100_MACCR_RX_BROADPKT)
 170
 171 static int ftmac100_start_hw(struct ftmac100 *priv)
 172 {
 173         struct net_device *netdev = priv->netdev;
 174
 175         if (ftmac100_reset(priv))
 176                 return -EIO;
 177
 178         /* setup ring buffer base registers */
 179         ftmac100_set_rx_ring_base(priv,
 180                                   priv->descs_dma_addr +
 181                                   offsetof(struct ftmac100_descs, rxdes));
 182         ftmac100_set_tx_ring_base(priv,
 183                                   priv->descs_dma_addr +
 184                                   offsetof(struct ftmac100_descs, txdes));
 185
 186         iowrite32(FTMAC100_APTC_RXPOLL_CNT(1), priv->base + FTMAC100_OFFSET_APTC);
 187
 188         ftmac100_set_mac(priv, netdev->dev_addr);
 189
 190         iowrite32(MACCR_ENABLE_ALL, priv->base + FTMAC100_OFFSET_MACCR);
 191         return 0;
 192 }
 193
 194 static void ftmac100_stop_hw(struct ftmac100 *priv)
 195 {
 196         iowrite32(0, priv->base + FTMAC100_OFFSET_MACCR);
 197 }
 198
 199 /******************************************************************************
 200  * internal functions (receive descriptor)
 201  *****************************************************************************/
 202 static bool ftmac100_rxdes_first_segment(struct ftmac100_rxdes *rxdes)
 203 {
 204         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_FRS);
 205 }
 206
 207 static bool ftmac100_rxdes_last_segment(struct ftmac100_rxdes *rxdes)
 208 {
 209         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_LRS);
 210 }
 211
 212 static bool ftmac100_rxdes_owned_by_dma(struct ftmac100_rxdes *rxdes)
 213 {
 214         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RXDMA_OWN);
 215 }
 216
 217 static void ftmac100_rxdes_set_dma_own(struct ftmac100_rxdes *rxdes)
 218 {
 219         /* clear status bits */
 220         rxdes->rxdes0 = cpu_to_le32(FTMAC100_RXDES0_RXDMA_OWN);
 221 }
 222
 223 static bool ftmac100_rxdes_rx_error(struct ftmac100_rxdes *rxdes)
 224 {
 225         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RX_ERR);
 226 }
 227
 228 static bool ftmac100_rxdes_crc_error(struct ftmac100_rxdes *rxdes)
 229 {
 230         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_CRC_ERR);
 231 }
 232
 233 static bool ftmac100_rxdes_frame_too_long(struct ftmac100_rxdes *rxdes)
 234 {
 235         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_FTL);
 236 }
 237
 238 static bool ftmac100_rxdes_runt(struct ftmac100_rxdes *rxdes)
 239 {
 240         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RUNT);
 241 }
 242
 243 static bool ftmac100_rxdes_odd_nibble(struct ftmac100_rxdes *rxdes)
 244 {
 245         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RX_ODD_NB);
 246 }
 247
 248 static unsigned int ftmac100_rxdes_frame_length(struct ftmac100_rxdes *rxdes)
 249 {
 250         return le32_to_cpu(rxdes->rxdes0) & FTMAC100_RXDES0_RFL;
 251 }
 252
 253 static bool ftmac100_rxdes_multicast(struct ftmac100_rxdes *rxdes)
 254 {
 255         return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_MULTICAST);
 256 }
 257
 258 static void ftmac100_rxdes_set_buffer_size(struct ftmac100_rxdes *rxdes,
 259                                            unsigned int size)
 260 {
 261         rxdes->rxdes1 &= cpu_to_le32(FTMAC100_RXDES1_EDORR);
 262         rxdes->rxdes1 |= cpu_to_le32(FTMAC100_RXDES1_RXBUF_SIZE(size));
 263 }
 264
 265 static void ftmac100_rxdes_set_end_of_ring(struct ftmac100_rxdes *rxdes)
 266 {
 267         rxdes->rxdes1 |= cpu_to_le32(FTMAC100_RXDES1_EDORR);
 268 }
 269
 270 static void ftmac100_rxdes_set_dma_addr(struct ftmac100_rxdes *rxdes,
 271                                         dma_addr_t addr)
 272 {
 273         rxdes->rxdes2 = cpu_to_le32(addr);
 274 }
 275
 276 static dma_addr_t ftmac100_rxdes_get_dma_addr(struct ftmac100_rxdes *rxdes)
 277 {
 278         return le32_to_cpu(rxdes->rxdes2);
 279 }
 280
 281 /*
 282  * rxdes3 is not used by hardware. We use it to keep track of page.
 283  * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
 284  */
 285 static void ftmac100_rxdes_set_page(struct ftmac100_rxdes *rxdes, struct page *page)
 286 {
 287         rxdes->rxdes3 = (unsigned int)page;
 288 }
 289
 290 static struct page *ftmac100_rxdes_get_page(struct ftmac100_rxdes *rxdes)
 291 {
 292         return (struct page *)rxdes->rxdes3;
 293 }
 294
 295 /******************************************************************************
 296  * internal functions (receive)
 297  *****************************************************************************/
 298 static int ftmac100_next_rx_pointer(int pointer)
 299 {
 300         return (pointer + 1) & (RX_QUEUE_ENTRIES - 1);
 301 }
 302
 303 static void ftmac100_rx_pointer_advance(struct ftmac100 *priv)
 304 {
 305         priv->rx_pointer = ftmac100_next_rx_pointer(priv->rx_pointer);
 306 }
 307
 308 static struct ftmac100_rxdes *ftmac100_current_rxdes(struct ftmac100 *priv)
 309 {
 310         return &priv->descs->rxdes[priv->rx_pointer];
 311 }
 312
 313 static struct ftmac100_rxdes *
 314 ftmac100_rx_locate_first_segment(struct ftmac100 *priv)
 315 {
 316         struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
 317
 318         while (!ftmac100_rxdes_owned_by_dma(rxdes)) {
 319                 if (ftmac100_rxdes_first_segment(rxdes))
 320                         return rxdes;
 321
 322                 ftmac100_rxdes_set_dma_own(rxdes);
 323                 ftmac100_rx_pointer_advance(priv);
 324                 rxdes = ftmac100_current_rxdes(priv);
 325         }
 326
 327         return NULL;
 328 }
 329
 330 static bool ftmac100_rx_packet_error(struct ftmac100 *priv,
 331                                      struct ftmac100_rxdes *rxdes)
 332 {
 333         struct net_device *netdev = priv->netdev;
 334         bool error = false;
 335
 336         if (unlikely(ftmac100_rxdes_rx_error(rxdes))) {
 337                 if (net_ratelimit())
 338                         netdev_info(netdev, "rx err\n");
 339
 340                 netdev->stats.rx_errors++;
 341                 error = true;
 342         }
 343
 344         if (unlikely(ftmac100_rxdes_crc_error(rxdes))) {
 345                 if (net_ratelimit())
 346                         netdev_info(netdev, "rx crc err\n");
 347
 348                 netdev->stats.rx_crc_errors++;
 349                 error = true;
 350         }
 351
 352         if (unlikely(ftmac100_rxdes_frame_too_long(rxdes))) {
 353                 if (net_ratelimit())
 354                         netdev_info(netdev, "rx frame too long\n");
 355
 356                 netdev->stats.rx_length_errors++;
 357                 error = true;
 358         } else if (unlikely(ftmac100_rxdes_runt(rxdes))) {
 359                 if (net_ratelimit())
 360                         netdev_info(netdev, "rx runt\n");
 361
 362                 netdev->stats.rx_length_errors++;
 363                 error = true;
 364         } else if (unlikely(ftmac100_rxdes_odd_nibble(rxdes))) {
 365                 if (net_ratelimit())
 366                         netdev_info(netdev, "rx odd nibble\n");
 367
 368                 netdev->stats.rx_length_errors++;
 369                 error = true;
 370         }
 371
 372         return error;
 373 }
 374
 375 static void ftmac100_rx_drop_packet(struct ftmac100 *priv)
 376 {
 377         struct net_device *netdev = priv->netdev;
 378         struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
 379         bool done = false;
 380
 381         if (net_ratelimit())
 382                 netdev_dbg(netdev, "drop packet %p\n", rxdes);
 383
 384         do {
 385                 if (ftmac100_rxdes_last_segment(rxdes))
 386                         done = true;
 387
 388                 ftmac100_rxdes_set_dma_own(rxdes);
 389                 ftmac100_rx_pointer_advance(priv);
 390                 rxdes = ftmac100_current_rxdes(priv);
 391         } while (!done && !ftmac100_rxdes_owned_by_dma(rxdes));
 392
 393         netdev->stats.rx_dropped++;
 394 }
 395
 396 static bool ftmac100_rx_packet(struct ftmac100 *priv, int *processed)
 397 {
 398         struct net_device *netdev = priv->netdev;
 399         struct ftmac100_rxdes *rxdes;
 400         struct sk_buff *skb;
 401         struct page *page;
 402         dma_addr_t map;
 403         int length;
 404
 405         rxdes = ftmac100_rx_locate_first_segment(priv);
 406         if (!rxdes)
 407                 return false;
 408
 409         if (unlikely(ftmac100_rx_packet_error(priv, rxdes))) {
 410                 ftmac100_rx_drop_packet(priv);
 411                 return true;
 412         }
 413
 414         /*
 415          * It is impossible to get multi-segment packets
 416          * because we always provide big enough receive buffers.
 417          */
 418         if (unlikely(!ftmac100_rxdes_last_segment(rxdes)))
 419                 BUG();
 420
 421         /* start processing */
 422         skb = netdev_alloc_skb_ip_align(netdev, 128);
 423         if (unlikely(!skb)) {
 424                 if (net_ratelimit())
 425                         netdev_err(netdev, "rx skb alloc failed\n");
 426
 427                 ftmac100_rx_drop_packet(priv);
 428                 return true;
 429         }
 430
 431         if (unlikely(ftmac100_rxdes_multicast(rxdes)))
 432                 netdev->stats.multicast++;
 433
 434         map = ftmac100_rxdes_get_dma_addr(rxdes);
 435         dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
 436
 437         length = ftmac100_rxdes_frame_length(rxdes);
 438         page = ftmac100_rxdes_get_page(rxdes);
 439         skb_fill_page_desc(skb, 0, page, 0, length);
 440         skb->len += length;
 441         skb->data_len += length;
 442         skb->truesize += length;
 443         __pskb_pull_tail(skb, min(length, 64));
 444
 445         ftmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
 446
 447         ftmac100_rx_pointer_advance(priv);
 448
 449         skb->protocol = eth_type_trans(skb, netdev);
 450
 451         netdev->stats.rx_packets++;
 452         netdev->stats.rx_bytes += skb->len;
 453
 454         /* push packet to protocol stack */
 455         netif_receive_skb(skb);
 456
 457         (*processed)++;
 458         return true;
 459 }
 460
 461 /******************************************************************************
 462  * internal functions (transmit descriptor)
 463  *****************************************************************************/
 464 static void ftmac100_txdes_reset(struct ftmac100_txdes *txdes)
 465 {
 466         /* clear all except end of ring bit */
 467         txdes->txdes0 = 0;
 468         txdes->txdes1 &= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
 469         txdes->txdes2 = 0;
 470         txdes->txdes3 = 0;
 471 }
 472
 473 static bool ftmac100_txdes_owned_by_dma(struct ftmac100_txdes *txdes)
 474 {
 475         return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
 476 }
 477
 478 static void ftmac100_txdes_set_dma_own(struct ftmac100_txdes *txdes)
 479 {
 480         /*
 481          * Make sure dma own bit will not be set before any other
 482          * descriptor fields.
 483          */
 484         wmb();
 485         txdes->txdes0 |= cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
 486 }
 487
 488 static bool ftmac100_txdes_excessive_collision(struct ftmac100_txdes *txdes)
 489 {
 490         return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_EXSCOL);
 491 }
 492
 493 static bool ftmac100_txdes_late_collision(struct ftmac100_txdes *txdes)
 494 {
 495         return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_LATECOL);
 496 }
 497
 498 static void ftmac100_txdes_set_end_of_ring(struct ftmac100_txdes *txdes)
 499 {
 500         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
 501 }
 502
 503 static void ftmac100_txdes_set_first_segment(struct ftmac100_txdes *txdes)
 504 {
 505         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_FTS);
 506 }
 507
 508 static void ftmac100_txdes_set_last_segment(struct ftmac100_txdes *txdes)
 509 {
 510         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_LTS);
 511 }
 512
 513 static void ftmac100_txdes_set_txint(struct ftmac100_txdes *txdes)
 514 {
 515         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXIC);
 516 }
 517
 518 static void ftmac100_txdes_set_buffer_size(struct ftmac100_txdes *txdes,
 519                                            unsigned int len)
 520 {
 521         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXBUF_SIZE(len));
 522 }
 523
 524 static void ftmac100_txdes_set_dma_addr(struct ftmac100_txdes *txdes,
 525                                         dma_addr_t addr)
 526 {
 527         txdes->txdes2 = cpu_to_le32(addr);
 528 }
 529
 530 static dma_addr_t ftmac100_txdes_get_dma_addr(struct ftmac100_txdes *txdes)
 531 {
 532         return le32_to_cpu(txdes->txdes2);
 533 }
 534
 535 /*
 536  * txdes3 is not used by hardware. We use it to keep track of socket buffer.
 537  * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
 538  */
 539 static void ftmac100_txdes_set_skb(struct ftmac100_txdes *txdes, struct sk_buff *skb)
 540 {
 541         txdes->txdes3 = (unsigned int)skb;
 542 }
 543
 544 static struct sk_buff *ftmac100_txdes_get_skb(struct ftmac100_txdes *txdes)
 545 {
 546         return (struct sk_buff *)txdes->txdes3;
 547 }
 548
 549 /******************************************************************************
 550  * internal functions (transmit)
 551  *****************************************************************************/
 552 static int ftmac100_next_tx_pointer(int pointer)
 553 {
 554         return (pointer + 1) & (TX_QUEUE_ENTRIES - 1);
 555 }
 556
 557 static void ftmac100_tx_pointer_advance(struct ftmac100 *priv)
 558 {
 559         priv->tx_pointer = ftmac100_next_tx_pointer(priv->tx_pointer);
 560 }
 561
 562 static void ftmac100_tx_clean_pointer_advance(struct ftmac100 *priv)
 563 {
 564         priv->tx_clean_pointer = ftmac100_next_tx_pointer(priv->tx_clean_pointer);
 565 }
 566
 567 static struct ftmac100_txdes *ftmac100_current_txdes(struct ftmac100 *priv)
 568 {
 569         return &priv->descs->txdes[priv->tx_pointer];
 570 }
 571
 572 static struct ftmac100_txdes *ftmac100_current_clean_txdes(struct ftmac100 *priv)
 573 {
 574         return &priv->descs->txdes[priv->tx_clean_pointer];
 575 }
 576
 577 static bool ftmac100_tx_complete_packet(struct ftmac100 *priv)
 578 {
 579         struct net_device *netdev = priv->netdev;
 580         struct ftmac100_txdes *txdes;
 581         struct sk_buff *skb;
 582         dma_addr_t map;
 583
 584         if (priv->tx_pending == 0)
 585                 return false;
 586
 587         txdes = ftmac100_current_clean_txdes(priv);
 588
 589         if (ftmac100_txdes_owned_by_dma(txdes))
 590                 return false;
 591
 592         skb = ftmac100_txdes_get_skb(txdes);
 593         map = ftmac100_txdes_get_dma_addr(txdes);
 594
 595         if (unlikely(ftmac100_txdes_excessive_collision(txdes) ||
 596                      ftmac100_txdes_late_collision(txdes))) {
 597                 /*
 598                  * packet transmitted to ethernet lost due to late collision
 599                  * or excessive collision
 600                  */
 601                 netdev->stats.tx_aborted_errors++;
 602         } else {
 603                 netdev->stats.tx_packets++;
 604                 netdev->stats.tx_bytes += skb->len;
 605         }
 606
 607         dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
 608         dev_kfree_skb(skb);
 609
 610         ftmac100_txdes_reset(txdes);
 611
 612         ftmac100_tx_clean_pointer_advance(priv);
 613
 614         spin_lock(&priv->tx_lock);
 615         priv->tx_pending--;
 616         spin_unlock(&priv->tx_lock);
 617         netif_wake_queue(netdev);
 618
 619         return true;
 620 }
 621
 622 static void ftmac100_tx_complete(struct ftmac100 *priv)
 623 {
 624         while (ftmac100_tx_complete_packet(priv))
 625                 ;
 626 }
 627
 628 static int ftmac100_xmit(struct ftmac100 *priv, struct sk_buff *skb,
 629                          dma_addr_t map)
 630 {
 631         struct net_device *netdev = priv->netdev;
 632         struct ftmac100_txdes *txdes;
 633         unsigned int len = (skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len;
 634
 635         txdes = ftmac100_current_txdes(priv);
 636         ftmac100_tx_pointer_advance(priv);
 637
 638         /* setup TX descriptor */
 639         ftmac100_txdes_set_skb(txdes, skb);
 640         ftmac100_txdes_set_dma_addr(txdes, map);
 641
 642         ftmac100_txdes_set_first_segment(txdes);
 643         ftmac100_txdes_set_last_segment(txdes);
 644         ftmac100_txdes_set_txint(txdes);
 645         ftmac100_txdes_set_buffer_size(txdes, len);
 646
 647         spin_lock(&priv->tx_lock);
 648         priv->tx_pending++;
 649         if (priv->tx_pending == TX_QUEUE_ENTRIES)
 650                 netif_stop_queue(netdev);
 651
 652         /* start transmit */
 653         ftmac100_txdes_set_dma_own(txdes);
 654         spin_unlock(&priv->tx_lock);
 655
 656         ftmac100_txdma_start_polling(priv);
 657         return NETDEV_TX_OK;
 658 }
 659
 660 /******************************************************************************
 661  * internal functions (buffer)
 662  *****************************************************************************/
 663 static int ftmac100_alloc_rx_page(struct ftmac100 *priv,
 664                                   struct ftmac100_rxdes *rxdes, gfp_t gfp)
 665 {
 666         struct net_device *netdev = priv->netdev;
 667         struct page *page;
 668         dma_addr_t map;
 669
 670         page = alloc_page(gfp);
 671         if (!page) {
 672                 if (net_ratelimit())
 673                         netdev_err(netdev, "failed to allocate rx page\n");
 674                 return -ENOMEM;
 675         }
 676
 677         map = dma_map_page(priv->dev, page, 0, RX_BUF_SIZE, DMA_FROM_DEVICE);
 678         if (unlikely(dma_mapping_error(priv->dev, map))) {
 679                 if (net_ratelimit())
 680                         netdev_err(netdev, "failed to map rx page\n");
 681                 __free_page(page);
 682                 return -ENOMEM;
 683         }
 684
 685         ftmac100_rxdes_set_page(rxdes, page);
 686         ftmac100_rxdes_set_dma_addr(rxdes, map);
 687         ftmac100_rxdes_set_buffer_size(rxdes, RX_BUF_SIZE);
 688         ftmac100_rxdes_set_dma_own(rxdes);
 689         return 0;
 690 }
 691
 692 static void ftmac100_free_buffers(struct ftmac100 *priv)
 693 {
 694         int i;
 695
 696         for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
 697                 struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
 698                 struct page *page = ftmac100_rxdes_get_page(rxdes);
 699                 dma_addr_t map = ftmac100_rxdes_get_dma_addr(rxdes);
 700
 701                 if (!page)
 702                         continue;
 703
 704                 dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
 705                 __free_page(page);
 706         }
 707
 708         for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
 709                 struct ftmac100_txdes *txdes = &priv->descs->txdes[i];
 710                 struct sk_buff *skb = ftmac100_txdes_get_skb(txdes);
 711                 dma_addr_t map = ftmac100_txdes_get_dma_addr(txdes);
 712
 713                 if (!skb)
 714                         continue;
 715
 716                 dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
 717                 dev_kfree_skb(skb);
 718         }
 719
 720         dma_free_coherent(priv->dev, sizeof(struct ftmac100_descs),
 721                           priv->descs, priv->descs_dma_addr);
 722 }
 723
 724 static int ftmac100_alloc_buffers(struct ftmac100 *priv)
 725 {
 726         int i;
 727
 728         priv->descs = dma_alloc_coherent(priv->dev, sizeof(struct ftmac100_descs),
 729                                          &priv->descs_dma_addr, GFP_KERNEL);
 730         if (!priv->descs)
 731                 return -ENOMEM;
 732
 733         memset(priv->descs, 0, sizeof(struct ftmac100_descs));
 734
 735         /* initialize RX ring */
 736         ftmac100_rxdes_set_end_of_ring(&priv->descs->rxdes[RX_QUEUE_ENTRIES - 1]);
 737
 738         for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
 739                 struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
 740
 741                 if (ftmac100_alloc_rx_page(priv, rxdes, GFP_KERNEL))
 742                         goto err;
 743         }
 744
 745         /* initialize TX ring */
 746         ftmac100_txdes_set_end_of_ring(&priv->descs->txdes[TX_QUEUE_ENTRIES - 1]);
 747         return 0;
 748
 749 err:
 750         ftmac100_free_buffers(priv);
 751         return -ENOMEM;
 752 }
 753
 754 /******************************************************************************
 755  * struct mii_if_info functions
 756  *****************************************************************************/
 757 static int ftmac100_mdio_read(struct net_device *netdev, int phy_id, int reg)
 758 {
 759         struct ftmac100 *priv = netdev_priv(netdev);
 760         unsigned int phycr;
 761         int i;
 762
 763         phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
 764                 FTMAC100_PHYCR_REGAD(reg) |
 765                 FTMAC100_PHYCR_MIIRD;
 766
 767         iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
 768
 769         for (i = 0; i < 10; i++) {
 770                 phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
 771
 772                 if ((phycr & FTMAC100_PHYCR_MIIRD) == 0)
 773                         return phycr & FTMAC100_PHYCR_MIIRDATA;
 774
 775                 udelay(100);
 776         }
 777
 778         netdev_err(netdev, "mdio read timed out\n");
 779         return 0;
 780 }
 781
 782 static void ftmac100_mdio_write(struct net_device *netdev, int phy_id, int reg,
 783                                 int data)
 784 {
 785         struct ftmac100 *priv = netdev_priv(netdev);
 786         unsigned int phycr;
 787         int i;
 788
 789         phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
 790                 FTMAC100_PHYCR_REGAD(reg) |
 791                 FTMAC100_PHYCR_MIIWR;
 792
 793         data = FTMAC100_PHYWDATA_MIIWDATA(data);
 794
 795         iowrite32(data, priv->base + FTMAC100_OFFSET_PHYWDATA);
 796         iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
 797
 798         for (i = 0; i < 10; i++) {
 799                 phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
 800
 801                 if ((phycr & FTMAC100_PHYCR_MIIWR) == 0)
 802                         return;
 803
 804                 udelay(100);
 805         }
 806
 807         netdev_err(netdev, "mdio write timed out\n");
 808 }
 809
 810 /******************************************************************************
 811  * struct ethtool_ops functions
 812  *****************************************************************************/
 813 static void ftmac100_get_drvinfo(struct net_device *netdev,
 814                                  struct ethtool_drvinfo *info)
 815 {
 816         strcpy(info->driver, DRV_NAME);
 817         strcpy(info->version, DRV_VERSION);
 818         strcpy(info->bus_info, dev_name(&netdev->dev));
 819 }
 820
 821 static int ftmac100_get_settings(struct net_device *netdev, struct ethtool_cmd *cmd)
 822 {
 823         struct ftmac100 *priv = netdev_priv(netdev);
 824         return mii_ethtool_gset(&priv->mii, cmd);
 825 }
 826
 827 static int ftmac100_set_settings(struct net_device *netdev, struct ethtool_cmd *cmd)
 828 {
 829         struct ftmac100 *priv = netdev_priv(netdev);
 830         return mii_ethtool_sset(&priv->mii, cmd);
 831 }
 832
 833 static int ftmac100_nway_reset(struct net_device *netdev)
 834 {
 835         struct ftmac100 *priv = netdev_priv(netdev);
 836         return mii_nway_restart(&priv->mii);
 837 }
 838
 839 static u32 ftmac100_get_link(struct net_device *netdev)
 840 {
 841         struct ftmac100 *priv = netdev_priv(netdev);
 842         return mii_link_ok(&priv->mii);
 843 }
 844
 845 static const struct ethtool_ops ftmac100_ethtool_ops = {
 846         .set_settings           = ftmac100_set_settings,
 847         .get_settings           = ftmac100_get_settings,
 848         .get_drvinfo            = ftmac100_get_drvinfo,
 849         .nway_reset             = ftmac100_nway_reset,
 850         .get_link               = ftmac100_get_link,
 851 };
 852
 853 /******************************************************************************
 854  * interrupt handler
 855  *****************************************************************************/
 856 static irqreturn_t ftmac100_interrupt(int irq, void *dev_id)
 857 {
 858         struct net_device *netdev = dev_id;
 859         struct ftmac100 *priv = netdev_priv(netdev);
 860
 861         if (likely(netif_running(netdev))) {
 862                 /* Disable interrupts for polling */
 863                 ftmac100_disable_all_int(priv);
 864                 napi_schedule(&priv->napi);
 865         }
 866
 867         return IRQ_HANDLED;
 868 }
 869
 870 /******************************************************************************
 871  * struct napi_struct functions
 872  *****************************************************************************/
 873 static int ftmac100_poll(struct napi_struct *napi, int budget)
 874 {
 875         struct ftmac100 *priv = container_of(napi, struct ftmac100, napi);
 876         struct net_device *netdev = priv->netdev;
 877         unsigned int status;
 878         bool completed = true;
 879         int rx = 0;
 880
 881         status = ioread32(priv->base + FTMAC100_OFFSET_ISR);
 882
 883         if (status & (FTMAC100_INT_RPKT_FINISH | FTMAC100_INT_NORXBUF)) {
 884                 /*
 885                  * FTMAC100_INT_RPKT_FINISH:
 886                  *      RX DMA has received packets into RX buffer successfully
 887                  *
 888                  * FTMAC100_INT_NORXBUF:
 889                  *      RX buffer unavailable
 890                  */
 891                 bool retry;
 892
 893                 do {
 894                         retry = ftmac100_rx_packet(priv, &rx);
 895                 } while (retry && rx < budget);
 896
 897                 if (retry && rx == budget)
 898                         completed = false;
 899         }
 900
 901         if (status & (FTMAC100_INT_XPKT_OK | FTMAC100_INT_XPKT_LOST)) {
 902                 /*
 903                  * FTMAC100_INT_XPKT_OK:
 904                  *      packet transmitted to ethernet successfully
 905                  *
 906                  * FTMAC100_INT_XPKT_LOST:
 907                  *      packet transmitted to ethernet lost due to late
 908                  *      collision or excessive collision
 909                  */
 910                 ftmac100_tx_complete(priv);
 911         }
 912
 913         if (status & (FTMAC100_INT_NORXBUF | FTMAC100_INT_RPKT_LOST |
 914                       FTMAC100_INT_AHB_ERR | FTMAC100_INT_PHYSTS_CHG)) {
 915                 if (net_ratelimit())
 916                         netdev_info(netdev, "[ISR] = 0x%x: %s%s%s%s\n", status,
 917                                     status & FTMAC100_INT_NORXBUF ? "NORXBUF " : "",
 918                                     status & FTMAC100_INT_RPKT_LOST ? "RPKT_LOST " : "",
 919                                     status & FTMAC100_INT_AHB_ERR ? "AHB_ERR " : "",
 920                                     status & FTMAC100_INT_PHYSTS_CHG ? "PHYSTS_CHG" : "");
 921
 922                 if (status & FTMAC100_INT_NORXBUF) {
 923                         /* RX buffer unavailable */
 924                         netdev->stats.rx_over_errors++;
 925                 }
 926
 927                 if (status & FTMAC100_INT_RPKT_LOST) {
 928                         /* received packet lost due to RX FIFO full */
 929                         netdev->stats.rx_fifo_errors++;
 930                 }
 931
 932                 if (status & FTMAC100_INT_PHYSTS_CHG) {
 933                         /* PHY link status change */
 934                         mii_check_link(&priv->mii);
 935                 }
 936         }
 937
 938         if (completed) {
 939                 /* stop polling */
 940                 napi_complete(napi);
 941                 ftmac100_enable_all_int(priv);
 942         }
 943
 944         return rx;
 945 }
 946
 947 /******************************************************************************
 948  * struct net_device_ops functions
 949  *****************************************************************************/
 950 static int ftmac100_open(struct net_device *netdev)
 951 {
 952         struct ftmac100 *priv = netdev_priv(netdev);
 953         int err;
 954
 955         err = ftmac100_alloc_buffers(priv);
 956         if (err) {
 957                 netdev_err(netdev, "failed to allocate buffers\n");
 958                 goto err_alloc;
 959         }
 960
 961         err = request_irq(priv->irq, ftmac100_interrupt, 0, netdev->name, netdev);
 962         if (err) {
 963                 netdev_err(netdev, "failed to request irq %d\n", priv->irq);
 964                 goto err_irq;
 965         }
 966
 967         priv->rx_pointer = 0;
 968         priv->tx_clean_pointer = 0;
 969         priv->tx_pointer = 0;
 970         priv->tx_pending = 0;
 971
 972         err = ftmac100_start_hw(priv);
 973         if (err)
 974                 goto err_hw;
 975
 976         napi_enable(&priv->napi);
 977         netif_start_queue(netdev);
 978
 979         ftmac100_enable_all_int(priv);
 980
 981         return 0;
 982
 983 err_hw:
 984         free_irq(priv->irq, netdev);
 985 err_irq:
 986         ftmac100_free_buffers(priv);
 987 err_alloc:
 988         return err;
 989 }
 990
 991 static int ftmac100_stop(struct net_device *netdev)
 992 {
 993         struct ftmac100 *priv = netdev_priv(netdev);
 994
 995         ftmac100_disable_all_int(priv);
 996         netif_stop_queue(netdev);
 997         napi_disable(&priv->napi);
 998         ftmac100_stop_hw(priv);
 999         free_irq(priv->irq, netdev);
1000         ftmac100_free_buffers(priv);
1001
1002         return 0;
1003 }
1004
1005 static int ftmac100_hard_start_xmit(struct sk_buff *skb, struct net_device *netdev)
1006 {
1007         struct ftmac100 *priv = netdev_priv(netdev);
1008         dma_addr_t map;
1009
1010         if (unlikely(skb->len > MAX_PKT_SIZE)) {
1011                 if (net_ratelimit())
1012                         netdev_dbg(netdev, "tx packet too big\n");
1013
1014                 netdev->stats.tx_dropped++;
1015                 dev_kfree_skb(skb);
1016                 return NETDEV_TX_OK;
1017         }
1018
1019         map = dma_map_single(priv->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
1020         if (unlikely(dma_mapping_error(priv->dev, map))) {
1021                 /* drop packet */
1022                 if (net_ratelimit())
1023                         netdev_err(netdev, "map socket buffer failed\n");
1024
1025                 netdev->stats.tx_dropped++;
1026                 dev_kfree_skb(skb);
1027                 return NETDEV_TX_OK;
1028         }
1029
1030         return ftmac100_xmit(priv, skb, map);
1031 }
1032
1033 /* optional */
1034 static int ftmac100_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1035 {
1036         struct ftmac100 *priv = netdev_priv(netdev);
1037         struct mii_ioctl_data *data = if_mii(ifr);
1038
1039         return generic_mii_ioctl(&priv->mii, data, cmd, NULL);
1040 }
1041
1042 static const struct net_device_ops ftmac100_netdev_ops = {
1043         .ndo_open               = ftmac100_open,
1044         .ndo_stop               = ftmac100_stop,
1045         .ndo_start_xmit         = ftmac100_hard_start_xmit,
1046         .ndo_set_mac_address    = eth_mac_addr,
1047         .ndo_validate_addr      = eth_validate_addr,
1048         .ndo_do_ioctl           = ftmac100_do_ioctl,
1049 };
1050
1051 /******************************************************************************
1052  * struct platform_driver functions
1053  *****************************************************************************/
1054 static int ftmac100_probe(struct platform_device *pdev)
1055 {
1056         struct resource *res;
1057         int irq;
1058         struct net_device *netdev;
1059         struct ftmac100 *priv;
1060         int err;
1061
1062         if (!pdev)
1063                 return -ENODEV;
1064
1065         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1066         if (!res)
1067                 return -ENXIO;
1068
1069         irq = platform_get_irq(pdev, 0);
1070         if (irq < 0)
1071                 return irq;
1072
1073         /* setup net_device */
1074         netdev = alloc_etherdev(sizeof(*priv));
1075         if (!netdev) {
1076                 err = -ENOMEM;
1077                 goto err_alloc_etherdev;
1078         }
1079
1080         SET_NETDEV_DEV(netdev, &pdev->dev);
1081         SET_ETHTOOL_OPS(netdev, &ftmac100_ethtool_ops);
1082         netdev->netdev_ops = &ftmac100_netdev_ops;
1083
1084         platform_set_drvdata(pdev, netdev);
1085
1086         /* setup private data */
1087         priv = netdev_priv(netdev);
1088         priv->netdev = netdev;
1089         priv->dev = &pdev->dev;
1090
1091         spin_lock_init(&priv->tx_lock);
1092
1093         /* initialize NAPI */
1094         netif_napi_add(netdev, &priv->napi, ftmac100_poll, 64);
1095
1096         /* map io memory */
1097         priv->res = request_mem_region(res->start, resource_size(res),
1098                                        dev_name(&pdev->dev));
1099         if (!priv->res) {
1100                 dev_err(&pdev->dev, "Could not reserve memory region\n");
1101                 err = -ENOMEM;
1102                 goto err_req_mem;
1103         }
1104
1105         priv->base = ioremap(res->start, resource_size(res));
1106         if (!priv->base) {
1107                 dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1108                 err = -EIO;
1109                 goto err_ioremap;
1110         }
1111
1112         priv->irq = irq;
1113
1114         /* initialize struct mii_if_info */
1115         priv->mii.phy_id        = 0;
1116         priv->mii.phy_id_mask   = 0x1f;
1117         priv->mii.reg_num_mask  = 0x1f;
1118         priv->mii.dev           = netdev;
1119         priv->mii.mdio_read     = ftmac100_mdio_read;
1120         priv->mii.mdio_write    = ftmac100_mdio_write;
1121
1122         /* register network device */
1123         err = register_netdev(netdev);
1124         if (err) {
1125                 dev_err(&pdev->dev, "Failed to register netdev\n");
1126                 goto err_register_netdev;
1127         }
1128
1129         netdev_info(netdev, "irq %d, mapped at %p\n", priv->irq, priv->base);
1130
1131         if (!is_valid_ether_addr(netdev->dev_addr)) {
1132                 random_ether_addr(netdev->dev_addr);
1133                 netdev_info(netdev, "generated random MAC address %pM\n",
1134                             netdev->dev_addr);
1135         }
1136
1137         return 0;
1138
1139 err_register_netdev:
1140         iounmap(priv->base);
1141 err_ioremap:
1142         release_resource(priv->res);
1143 err_req_mem:
1144         netif_napi_del(&priv->napi);
1145         platform_set_drvdata(pdev, NULL);
1146         free_netdev(netdev);
1147 err_alloc_etherdev:
1148         return err;
1149 }
1150
1151 static int __exit ftmac100_remove(struct platform_device *pdev)
1152 {
1153         struct net_device *netdev;
1154         struct ftmac100 *priv;
1155
1156         netdev = platform_get_drvdata(pdev);
1157         priv = netdev_priv(netdev);
1158
1159         unregister_netdev(netdev);
1160
1161         iounmap(priv->base);
1162         release_resource(priv->res);
1163
1164         netif_napi_del(&priv->napi);
1165         platform_set_drvdata(pdev, NULL);
1166         free_netdev(netdev);
1167         return 0;
1168 }
1169
1170 static struct platform_driver ftmac100_driver = {
1171         .probe          = ftmac100_probe,
1172         .remove         = __exit_p(ftmac100_remove),
1173         .driver         = {
1174                 .name   = DRV_NAME,
1175                 .owner  = THIS_MODULE,
1176         },
1177 };
1178
1179 /******************************************************************************
1180  * initialization / finalization
1181  *****************************************************************************/
1182 static int __init ftmac100_init(void)
1183 {
1184         pr_info("Loading version " DRV_VERSION " ...\n");
1185         return platform_driver_register(&ftmac100_driver);
1186 }
1187
1188 static void __exit ftmac100_exit(void)
1189 {
1190         platform_driver_unregister(&ftmac100_driver);
1191 }
1192
1193 module_init(ftmac100_init);
1194 module_exit(ftmac100_exit);
1195
1196 MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
1197 MODULE_DESCRIPTION("FTMAC100 driver");
1198 MODULE_LICENSE("GPL");