drivers/net/ethernet/faraday/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
 443         /* page might be freed in __pskb_pull_tail() */
 444         if (length > 64)
 445                 skb->truesize += PAGE_SIZE;
 446         __pskb_pull_tail(skb, min(length, 64));
 447
 448         ftmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
 449
 450         ftmac100_rx_pointer_advance(priv);
 451
 452         skb->protocol = eth_type_trans(skb, netdev);
 453
 454         netdev->stats.rx_packets++;
 455         netdev->stats.rx_bytes += skb->len;
 456
 457         /* push packet to protocol stack */
 458         netif_receive_skb(skb);
 459
 460         (*processed)++;
 461         return true;
 462 }
 463
 464 /******************************************************************************
 465  * internal functions (transmit descriptor)
 466  *****************************************************************************/
 467 static void ftmac100_txdes_reset(struct ftmac100_txdes *txdes)
 468 {
 469         /* clear all except end of ring bit */
 470         txdes->txdes0 = 0;
 471         txdes->txdes1 &= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
 472         txdes->txdes2 = 0;
 473         txdes->txdes3 = 0;
 474 }
 475
 476 static bool ftmac100_txdes_owned_by_dma(struct ftmac100_txdes *txdes)
 477 {
 478         return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
 479 }
 480
 481 static void ftmac100_txdes_set_dma_own(struct ftmac100_txdes *txdes)
 482 {
 483         /*
 484          * Make sure dma own bit will not be set before any other
 485          * descriptor fields.
 486          */
 487         wmb();
 488         txdes->txdes0 |= cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
 489 }
 490
 491 static bool ftmac100_txdes_excessive_collision(struct ftmac100_txdes *txdes)
 492 {
 493         return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_EXSCOL);
 494 }
 495
 496 static bool ftmac100_txdes_late_collision(struct ftmac100_txdes *txdes)
 497 {
 498         return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_LATECOL);
 499 }
 500
 501 static void ftmac100_txdes_set_end_of_ring(struct ftmac100_txdes *txdes)
 502 {
 503         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
 504 }
 505
 506 static void ftmac100_txdes_set_first_segment(struct ftmac100_txdes *txdes)
 507 {
 508         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_FTS);
 509 }
 510
 511 static void ftmac100_txdes_set_last_segment(struct ftmac100_txdes *txdes)
 512 {
 513         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_LTS);
 514 }
 515
 516 static void ftmac100_txdes_set_txint(struct ftmac100_txdes *txdes)
 517 {
 518         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXIC);
 519 }
 520
 521 static void ftmac100_txdes_set_buffer_size(struct ftmac100_txdes *txdes,
 522                                            unsigned int len)
 523 {
 524         txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXBUF_SIZE(len));
 525 }
 526
 527 static void ftmac100_txdes_set_dma_addr(struct ftmac100_txdes *txdes,
 528                                         dma_addr_t addr)
 529 {
 530         txdes->txdes2 = cpu_to_le32(addr);
 531 }
 532
 533 static dma_addr_t ftmac100_txdes_get_dma_addr(struct ftmac100_txdes *txdes)
 534 {
 535         return le32_to_cpu(txdes->txdes2);
 536 }
 537
 538 /*
 539  * txdes3 is not used by hardware. We use it to keep track of socket buffer.
 540  * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
 541  */
 542 static void ftmac100_txdes_set_skb(struct ftmac100_txdes *txdes, struct sk_buff *skb)
 543 {
 544         txdes->txdes3 = (unsigned int)skb;
 545 }
 546
 547 static struct sk_buff *ftmac100_txdes_get_skb(struct ftmac100_txdes *txdes)
 548 {
 549         return (struct sk_buff *)txdes->txdes3;
 550 }
 551
 552 /******************************************************************************
 553  * internal functions (transmit)
 554  *****************************************************************************/
 555 static int ftmac100_next_tx_pointer(int pointer)
 556 {
 557         return (pointer + 1) & (TX_QUEUE_ENTRIES - 1);
 558 }
 559
 560 static void ftmac100_tx_pointer_advance(struct ftmac100 *priv)
 561 {
 562         priv->tx_pointer = ftmac100_next_tx_pointer(priv->tx_pointer);
 563 }
 564
 565 static void ftmac100_tx_clean_pointer_advance(struct ftmac100 *priv)
 566 {
 567         priv->tx_clean_pointer = ftmac100_next_tx_pointer(priv->tx_clean_pointer);
 568 }
 569
 570 static struct ftmac100_txdes *ftmac100_current_txdes(struct ftmac100 *priv)
 571 {
 572         return &priv->descs->txdes[priv->tx_pointer];
 573 }
 574
 575 static struct ftmac100_txdes *ftmac100_current_clean_txdes(struct ftmac100 *priv)
 576 {
 577         return &priv->descs->txdes[priv->tx_clean_pointer];
 578 }
 579
 580 static bool ftmac100_tx_complete_packet(struct ftmac100 *priv)
 581 {
 582         struct net_device *netdev = priv->netdev;
 583         struct ftmac100_txdes *txdes;
 584         struct sk_buff *skb;
 585         dma_addr_t map;
 586
 587         if (priv->tx_pending == 0)
 588                 return false;
 589
 590         txdes = ftmac100_current_clean_txdes(priv);
 591
 592         if (ftmac100_txdes_owned_by_dma(txdes))
 593                 return false;
 594
 595         skb = ftmac100_txdes_get_skb(txdes);
 596         map = ftmac100_txdes_get_dma_addr(txdes);
 597
 598         if (unlikely(ftmac100_txdes_excessive_collision(txdes) ||
 599                      ftmac100_txdes_late_collision(txdes))) {
 600                 /*
 601                  * packet transmitted to ethernet lost due to late collision
 602                  * or excessive collision
 603                  */
 604                 netdev->stats.tx_aborted_errors++;
 605         } else {
 606                 netdev->stats.tx_packets++;
 607                 netdev->stats.tx_bytes += skb->len;
 608         }
 609
 610         dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
 611         dev_kfree_skb(skb);
 612
 613         ftmac100_txdes_reset(txdes);
 614
 615         ftmac100_tx_clean_pointer_advance(priv);
 616
 617         spin_lock(&priv->tx_lock);
 618         priv->tx_pending--;
 619         spin_unlock(&priv->tx_lock);
 620         netif_wake_queue(netdev);
 621
 622         return true;
 623 }
 624
 625 static void ftmac100_tx_complete(struct ftmac100 *priv)
 626 {
 627         while (ftmac100_tx_complete_packet(priv))
 628                 ;
 629 }
 630
 631 static int ftmac100_xmit(struct ftmac100 *priv, struct sk_buff *skb,
 632                          dma_addr_t map)
 633 {
 634         struct net_device *netdev = priv->netdev;
 635         struct ftmac100_txdes *txdes;
 636         unsigned int len = (skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len;
 637
 638         txdes = ftmac100_current_txdes(priv);
 639         ftmac100_tx_pointer_advance(priv);
 640
 641         /* setup TX descriptor */
 642         ftmac100_txdes_set_skb(txdes, skb);
 643         ftmac100_txdes_set_dma_addr(txdes, map);
 644
 645         ftmac100_txdes_set_first_segment(txdes);
 646         ftmac100_txdes_set_last_segment(txdes);
 647         ftmac100_txdes_set_txint(txdes);
 648         ftmac100_txdes_set_buffer_size(txdes, len);
 649
 650         spin_lock(&priv->tx_lock);
 651         priv->tx_pending++;
 652         if (priv->tx_pending == TX_QUEUE_ENTRIES)
 653                 netif_stop_queue(netdev);
 654
 655         /* start transmit */
 656         ftmac100_txdes_set_dma_own(txdes);
 657         spin_unlock(&priv->tx_lock);
 658
 659         ftmac100_txdma_start_polling(priv);
 660         return NETDEV_TX_OK;
 661 }
 662
 663 /******************************************************************************
 664  * internal functions (buffer)
 665  *****************************************************************************/
 666 static int ftmac100_alloc_rx_page(struct ftmac100 *priv,
 667                                   struct ftmac100_rxdes *rxdes, gfp_t gfp)
 668 {
 669         struct net_device *netdev = priv->netdev;
 670         struct page *page;
 671         dma_addr_t map;
 672
 673         page = alloc_page(gfp);
 674         if (!page) {
 675                 if (net_ratelimit())
 676                         netdev_err(netdev, "failed to allocate rx page\n");
 677                 return -ENOMEM;
 678         }
 679
 680         map = dma_map_page(priv->dev, page, 0, RX_BUF_SIZE, DMA_FROM_DEVICE);
 681         if (unlikely(dma_mapping_error(priv->dev, map))) {
 682                 if (net_ratelimit())
 683                         netdev_err(netdev, "failed to map rx page\n");
 684                 __free_page(page);
 685                 return -ENOMEM;
 686         }
 687
 688         ftmac100_rxdes_set_page(rxdes, page);
 689         ftmac100_rxdes_set_dma_addr(rxdes, map);
 690         ftmac100_rxdes_set_buffer_size(rxdes, RX_BUF_SIZE);
 691         ftmac100_rxdes_set_dma_own(rxdes);
 692         return 0;
 693 }
 694
 695 static void ftmac100_free_buffers(struct ftmac100 *priv)
 696 {
 697         int i;
 698
 699         for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
 700                 struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
 701                 struct page *page = ftmac100_rxdes_get_page(rxdes);
 702                 dma_addr_t map = ftmac100_rxdes_get_dma_addr(rxdes);
 703
 704                 if (!page)
 705                         continue;
 706
 707                 dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
 708                 __free_page(page);
 709         }
 710
 711         for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
 712                 struct ftmac100_txdes *txdes = &priv->descs->txdes[i];
 713                 struct sk_buff *skb = ftmac100_txdes_get_skb(txdes);
 714                 dma_addr_t map = ftmac100_txdes_get_dma_addr(txdes);
 715
 716                 if (!skb)
 717                         continue;
 718
 719                 dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
 720                 dev_kfree_skb(skb);
 721         }
 722
 723         dma_free_coherent(priv->dev, sizeof(struct ftmac100_descs),
 724                           priv->descs, priv->descs_dma_addr);
 725 }
 726
 727 static int ftmac100_alloc_buffers(struct ftmac100 *priv)
 728 {
 729         int i;
 730
 731         priv->descs = dma_alloc_coherent(priv->dev, sizeof(struct ftmac100_descs),
 732                                          &priv->descs_dma_addr, GFP_KERNEL);
 733         if (!priv->descs)
 734                 return -ENOMEM;
 735
 736         memset(priv->descs, 0, sizeof(struct ftmac100_descs));
 737
 738         /* initialize RX ring */
 739         ftmac100_rxdes_set_end_of_ring(&priv->descs->rxdes[RX_QUEUE_ENTRIES - 1]);
 740
 741         for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
 742                 struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
 743
 744                 if (ftmac100_alloc_rx_page(priv, rxdes, GFP_KERNEL))
 745                         goto err;
 746         }
 747
 748         /* initialize TX ring */
 749         ftmac100_txdes_set_end_of_ring(&priv->descs->txdes[TX_QUEUE_ENTRIES - 1]);
 750         return 0;
 751
 752 err:
 753         ftmac100_free_buffers(priv);
 754         return -ENOMEM;
 755 }
 756
 757 /******************************************************************************
 758  * struct mii_if_info functions
 759  *****************************************************************************/
 760 static int ftmac100_mdio_read(struct net_device *netdev, int phy_id, int reg)
 761 {
 762         struct ftmac100 *priv = netdev_priv(netdev);
 763         unsigned int phycr;
 764         int i;
 765
 766         phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
 767                 FTMAC100_PHYCR_REGAD(reg) |
 768                 FTMAC100_PHYCR_MIIRD;
 769
 770         iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
 771
 772         for (i = 0; i < 10; i++) {
 773                 phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
 774
 775                 if ((phycr & FTMAC100_PHYCR_MIIRD) == 0)
 776                         return phycr & FTMAC100_PHYCR_MIIRDATA;
 777
 778                 udelay(100);
 779         }
 780
 781         netdev_err(netdev, "mdio read timed out\n");
 782         return 0;
 783 }
 784
 785 static void ftmac100_mdio_write(struct net_device *netdev, int phy_id, int reg,
 786                                 int data)
 787 {
 788         struct ftmac100 *priv = netdev_priv(netdev);
 789         unsigned int phycr;
 790         int i;
 791
 792         phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
 793                 FTMAC100_PHYCR_REGAD(reg) |
 794                 FTMAC100_PHYCR_MIIWR;
 795
 796         data = FTMAC100_PHYWDATA_MIIWDATA(data);
 797
 798         iowrite32(data, priv->base + FTMAC100_OFFSET_PHYWDATA);
 799         iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
 800
 801         for (i = 0; i < 10; i++) {
 802                 phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
 803
 804                 if ((phycr & FTMAC100_PHYCR_MIIWR) == 0)
 805                         return;
 806
 807                 udelay(100);
 808         }
 809
 810         netdev_err(netdev, "mdio write timed out\n");
 811 }
 812
 813 /******************************************************************************
 814  * struct ethtool_ops functions
 815  *****************************************************************************/
 816 static void ftmac100_get_drvinfo(struct net_device *netdev,
 817                                  struct ethtool_drvinfo *info)
 818 {
 819         strcpy(info->driver, DRV_NAME);
 820         strcpy(info->version, DRV_VERSION);
 821         strcpy(info->bus_info, dev_name(&netdev->dev));
 822 }
 823
 824 static int ftmac100_get_settings(struct net_device *netdev, struct ethtool_cmd *cmd)
 825 {
 826         struct ftmac100 *priv = netdev_priv(netdev);
 827         return mii_ethtool_gset(&priv->mii, cmd);
 828 }
 829
 830 static int ftmac100_set_settings(struct net_device *netdev, struct ethtool_cmd *cmd)
 831 {
 832         struct ftmac100 *priv = netdev_priv(netdev);
 833         return mii_ethtool_sset(&priv->mii, cmd);
 834 }
 835
 836 static int ftmac100_nway_reset(struct net_device *netdev)
 837 {
 838         struct ftmac100 *priv = netdev_priv(netdev);
 839         return mii_nway_restart(&priv->mii);
 840 }
 841
 842 static u32 ftmac100_get_link(struct net_device *netdev)
 843 {
 844         struct ftmac100 *priv = netdev_priv(netdev);
 845         return mii_link_ok(&priv->mii);
 846 }
 847
 848 static const struct ethtool_ops ftmac100_ethtool_ops = {
 849         .set_settings           = ftmac100_set_settings,
 850         .get_settings           = ftmac100_get_settings,
 851         .get_drvinfo            = ftmac100_get_drvinfo,
 852         .nway_reset             = ftmac100_nway_reset,
 853         .get_link               = ftmac100_get_link,
 854 };
 855
 856 /******************************************************************************
 857  * interrupt handler
 858  *****************************************************************************/
 859 static irqreturn_t ftmac100_interrupt(int irq, void *dev_id)
 860 {
 861         struct net_device *netdev = dev_id;
 862         struct ftmac100 *priv = netdev_priv(netdev);
 863
 864         if (likely(netif_running(netdev))) {
 865                 /* Disable interrupts for polling */
 866                 ftmac100_disable_all_int(priv);
 867                 napi_schedule(&priv->napi);
 868         }
 869
 870         return IRQ_HANDLED;
 871 }
 872
 873 /******************************************************************************
 874  * struct napi_struct functions
 875  *****************************************************************************/
 876 static int ftmac100_poll(struct napi_struct *napi, int budget)
 877 {
 878         struct ftmac100 *priv = container_of(napi, struct ftmac100, napi);
 879         struct net_device *netdev = priv->netdev;
 880         unsigned int status;
 881         bool completed = true;
 882         int rx = 0;
 883
 884         status = ioread32(priv->base + FTMAC100_OFFSET_ISR);
 885
 886         if (status & (FTMAC100_INT_RPKT_FINISH | FTMAC100_INT_NORXBUF)) {
 887                 /*
 888                  * FTMAC100_INT_RPKT_FINISH:
 889                  *      RX DMA has received packets into RX buffer successfully
 890                  *
 891                  * FTMAC100_INT_NORXBUF:
 892                  *      RX buffer unavailable
 893                  */
 894                 bool retry;
 895
 896                 do {
 897                         retry = ftmac100_rx_packet(priv, &rx);
 898                 } while (retry && rx < budget);
 899
 900                 if (retry && rx == budget)
 901                         completed = false;
 902         }
 903
 904         if (status & (FTMAC100_INT_XPKT_OK | FTMAC100_INT_XPKT_LOST)) {
 905                 /*
 906                  * FTMAC100_INT_XPKT_OK:
 907                  *      packet transmitted to ethernet successfully
 908                  *
 909                  * FTMAC100_INT_XPKT_LOST:
 910                  *      packet transmitted to ethernet lost due to late
 911                  *      collision or excessive collision
 912                  */
 913                 ftmac100_tx_complete(priv);
 914         }
 915
 916         if (status & (FTMAC100_INT_NORXBUF | FTMAC100_INT_RPKT_LOST |
 917                       FTMAC100_INT_AHB_ERR | FTMAC100_INT_PHYSTS_CHG)) {
 918                 if (net_ratelimit())
 919                         netdev_info(netdev, "[ISR] = 0x%x: %s%s%s%s\n", status,
 920                                     status & FTMAC100_INT_NORXBUF ? "NORXBUF " : "",
 921                                     status & FTMAC100_INT_RPKT_LOST ? "RPKT_LOST " : "",
 922                                     status & FTMAC100_INT_AHB_ERR ? "AHB_ERR " : "",
 923                                     status & FTMAC100_INT_PHYSTS_CHG ? "PHYSTS_CHG" : "");
 924
 925                 if (status & FTMAC100_INT_NORXBUF) {
 926                         /* RX buffer unavailable */
 927                         netdev->stats.rx_over_errors++;
 928                 }
 929
 930                 if (status & FTMAC100_INT_RPKT_LOST) {
 931                         /* received packet lost due to RX FIFO full */
 932                         netdev->stats.rx_fifo_errors++;
 933                 }
 934
 935                 if (status & FTMAC100_INT_PHYSTS_CHG) {
 936                         /* PHY link status change */
 937                         mii_check_link(&priv->mii);
 938                 }
 939         }
 940
 941         if (completed) {
 942                 /* stop polling */
 943                 napi_complete(napi);
 944                 ftmac100_enable_all_int(priv);
 945         }
 946
 947         return rx;
 948 }
 949
 950 /******************************************************************************
 951  * struct net_device_ops functions
 952  *****************************************************************************/
 953 static int ftmac100_open(struct net_device *netdev)
 954 {
 955         struct ftmac100 *priv = netdev_priv(netdev);
 956         int err;
 957
 958         err = ftmac100_alloc_buffers(priv);
 959         if (err) {
 960                 netdev_err(netdev, "failed to allocate buffers\n");
 961                 goto err_alloc;
 962         }
 963
 964         err = request_irq(priv->irq, ftmac100_interrupt, 0, netdev->name, netdev);
 965         if (err) {
 966                 netdev_err(netdev, "failed to request irq %d\n", priv->irq);
 967                 goto err_irq;
 968         }
 969
 970         priv->rx_pointer = 0;
 971         priv->tx_clean_pointer = 0;
 972         priv->tx_pointer = 0;
 973         priv->tx_pending = 0;
 974
 975         err = ftmac100_start_hw(priv);
 976         if (err)
 977                 goto err_hw;
 978
 979         napi_enable(&priv->napi);
 980         netif_start_queue(netdev);
 981
 982         ftmac100_enable_all_int(priv);
 983
 984         return 0;
 985
 986 err_hw:
 987         free_irq(priv->irq, netdev);
 988 err_irq:
 989         ftmac100_free_buffers(priv);
 990 err_alloc:
 991         return err;
 992 }
 993
 994 static int ftmac100_stop(struct net_device *netdev)
 995 {
 996         struct ftmac100 *priv = netdev_priv(netdev);
 997
 998         ftmac100_disable_all_int(priv);
 999         netif_stop_queue(netdev);
1000         napi_disable(&priv->napi);
1001         ftmac100_stop_hw(priv);
1002         free_irq(priv->irq, netdev);
1003         ftmac100_free_buffers(priv);
1004
1005         return 0;
1006 }
1007
1008 static int ftmac100_hard_start_xmit(struct sk_buff *skb, struct net_device *netdev)
1009 {
1010         struct ftmac100 *priv = netdev_priv(netdev);
1011         dma_addr_t map;
1012
1013         if (unlikely(skb->len > MAX_PKT_SIZE)) {
1014                 if (net_ratelimit())
1015                         netdev_dbg(netdev, "tx packet too big\n");
1016
1017                 netdev->stats.tx_dropped++;
1018                 dev_kfree_skb(skb);
1019                 return NETDEV_TX_OK;
1020         }
1021
1022         map = dma_map_single(priv->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
1023         if (unlikely(dma_mapping_error(priv->dev, map))) {
1024                 /* drop packet */
1025                 if (net_ratelimit())
1026                         netdev_err(netdev, "map socket buffer failed\n");
1027
1028                 netdev->stats.tx_dropped++;
1029                 dev_kfree_skb(skb);
1030                 return NETDEV_TX_OK;
1031         }
1032
1033         return ftmac100_xmit(priv, skb, map);
1034 }
1035
1036 /* optional */
1037 static int ftmac100_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1038 {
1039         struct ftmac100 *priv = netdev_priv(netdev);
1040         struct mii_ioctl_data *data = if_mii(ifr);
1041
1042         return generic_mii_ioctl(&priv->mii, data, cmd, NULL);
1043 }
1044
1045 static const struct net_device_ops ftmac100_netdev_ops = {
1046         .ndo_open               = ftmac100_open,
1047         .ndo_stop               = ftmac100_stop,
1048         .ndo_start_xmit         = ftmac100_hard_start_xmit,
1049         .ndo_set_mac_address    = eth_mac_addr,
1050         .ndo_validate_addr      = eth_validate_addr,
1051         .ndo_do_ioctl           = ftmac100_do_ioctl,
1052 };
1053
1054 /******************************************************************************
1055  * struct platform_driver functions
1056  *****************************************************************************/
1057 static int ftmac100_probe(struct platform_device *pdev)
1058 {
1059         struct resource *res;
1060         int irq;
1061         struct net_device *netdev;
1062         struct ftmac100 *priv;
1063         int err;
1064
1065         if (!pdev)
1066                 return -ENODEV;
1067
1068         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1069         if (!res)
1070                 return -ENXIO;
1071
1072         irq = platform_get_irq(pdev, 0);
1073         if (irq < 0)
1074                 return irq;
1075
1076         /* setup net_device */
1077         netdev = alloc_etherdev(sizeof(*priv));
1078         if (!netdev) {
1079                 err = -ENOMEM;
1080                 goto err_alloc_etherdev;
1081         }
1082
1083         SET_NETDEV_DEV(netdev, &pdev->dev);
1084         SET_ETHTOOL_OPS(netdev, &ftmac100_ethtool_ops);
1085         netdev->netdev_ops = &ftmac100_netdev_ops;
1086
1087         platform_set_drvdata(pdev, netdev);
1088
1089         /* setup private data */
1090         priv = netdev_priv(netdev);
1091         priv->netdev = netdev;
1092         priv->dev = &pdev->dev;
1093
1094         spin_lock_init(&priv->tx_lock);
1095
1096         /* initialize NAPI */
1097         netif_napi_add(netdev, &priv->napi, ftmac100_poll, 64);
1098
1099         /* map io memory */
1100         priv->res = request_mem_region(res->start, resource_size(res),
1101                                        dev_name(&pdev->dev));
1102         if (!priv->res) {
1103                 dev_err(&pdev->dev, "Could not reserve memory region\n");
1104                 err = -ENOMEM;
1105                 goto err_req_mem;
1106         }
1107
1108         priv->base = ioremap(res->start, resource_size(res));
1109         if (!priv->base) {
1110                 dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1111                 err = -EIO;
1112                 goto err_ioremap;
1113         }
1114
1115         priv->irq = irq;
1116
1117         /* initialize struct mii_if_info */
1118         priv->mii.phy_id        = 0;
1119         priv->mii.phy_id_mask   = 0x1f;
1120         priv->mii.reg_num_mask  = 0x1f;
1121         priv->mii.dev           = netdev;
1122         priv->mii.mdio_read     = ftmac100_mdio_read;
1123         priv->mii.mdio_write    = ftmac100_mdio_write;
1124
1125         /* register network device */
1126         err = register_netdev(netdev);
1127         if (err) {
1128                 dev_err(&pdev->dev, "Failed to register netdev\n");
1129                 goto err_register_netdev;
1130         }
1131
1132         netdev_info(netdev, "irq %d, mapped at %p\n", priv->irq, priv->base);
1133
1134         if (!is_valid_ether_addr(netdev->dev_addr)) {
1135                 random_ether_addr(netdev->dev_addr);
1136                 netdev_info(netdev, "generated random MAC address %pM\n",
1137                             netdev->dev_addr);
1138         }
1139
1140         return 0;
1141
1142 err_register_netdev:
1143         iounmap(priv->base);
1144 err_ioremap:
1145         release_resource(priv->res);
1146 err_req_mem:
1147         netif_napi_del(&priv->napi);
1148         platform_set_drvdata(pdev, NULL);
1149         free_netdev(netdev);
1150 err_alloc_etherdev:
1151         return err;
1152 }
1153
1154 static int __exit ftmac100_remove(struct platform_device *pdev)
1155 {
1156         struct net_device *netdev;
1157         struct ftmac100 *priv;
1158
1159         netdev = platform_get_drvdata(pdev);
1160         priv = netdev_priv(netdev);
1161
1162         unregister_netdev(netdev);
1163
1164         iounmap(priv->base);
1165         release_resource(priv->res);
1166
1167         netif_napi_del(&priv->napi);
1168         platform_set_drvdata(pdev, NULL);
1169         free_netdev(netdev);
1170         return 0;
1171 }
1172
1173 static struct platform_driver ftmac100_driver = {
1174         .probe          = ftmac100_probe,
1175         .remove         = __exit_p(ftmac100_remove),
1176         .driver         = {
1177                 .name   = DRV_NAME,
1178                 .owner  = THIS_MODULE,
1179         },
1180 };
1181
1182 /******************************************************************************
1183  * initialization / finalization
1184  *****************************************************************************/
1185 static int __init ftmac100_init(void)
1186 {
1187         pr_info("Loading version " DRV_VERSION " ...\n");
1188         return platform_driver_register(&ftmac100_driver);
1189 }
1190
1191 static void __exit ftmac100_exit(void)
1192 {
1193         platform_driver_unregister(&ftmac100_driver);
1194 }
1195
1196 module_init(ftmac100_init);
1197 module_exit(ftmac100_exit);
1198
1199 MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
1200 MODULE_DESCRIPTION("FTMAC100 driver");
1201 MODULE_LICENSE("GPL");