1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2004-2013 Synopsys, Inc. (www.synopsys.com) 4 * 5 * Driver for the ARC EMAC 10100 (hardware revision 5) 6 * 7 * Contributors: 8 * Amit Bhor 9 * Sameer Dhavale 10 * Vineet Gupta 11 */ 12 13 #include <linux/crc32.h> 14 #include <linux/etherdevice.h> 15 #include <linux/interrupt.h> 16 #include <linux/io.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/of_address.h> 20 #include <linux/of_irq.h> 21 #include <linux/of_mdio.h> 22 #include <linux/of_net.h> 23 24 #include "emac.h" 25 26 static void arc_emac_restart(struct net_device *ndev); 27 28 /** 29 * arc_emac_tx_avail - Return the number of available slots in the tx ring. 30 * @priv: Pointer to ARC EMAC private data structure. 31 * 32 * returns: the number of slots available for transmission in tx the ring. 33 */ 34 static inline int arc_emac_tx_avail(struct arc_emac_priv *priv) 35 { 36 return (priv->txbd_dirty + TX_BD_NUM - priv->txbd_curr - 1) % TX_BD_NUM; 37 } 38 39 /** 40 * arc_emac_adjust_link - Adjust the PHY link duplex. 41 * @ndev: Pointer to the net_device structure. 42 * 43 * This function is called to change the duplex setting after auto negotiation 44 * is done by the PHY. 45 */ 46 static void arc_emac_adjust_link(struct net_device *ndev) 47 { 48 struct arc_emac_priv *priv = netdev_priv(ndev); 49 struct phy_device *phy_dev = ndev->phydev; 50 unsigned int reg, state_changed = 0; 51 52 if (priv->link != phy_dev->link) { 53 priv->link = phy_dev->link; 54 state_changed = 1; 55 } 56 57 if (priv->speed != phy_dev->speed) { 58 priv->speed = phy_dev->speed; 59 state_changed = 1; 60 if (priv->set_mac_speed) 61 priv->set_mac_speed(priv, priv->speed); 62 } 63 64 if (priv->duplex != phy_dev->duplex) { 65 reg = arc_reg_get(priv, R_CTRL); 66 67 if (phy_dev->duplex == DUPLEX_FULL) 68 reg |= ENFL_MASK; 69 else 70 reg &= ~ENFL_MASK; 71 72 arc_reg_set(priv, R_CTRL, reg); 73 priv->duplex = phy_dev->duplex; 74 state_changed = 1; 75 } 76 77 if (state_changed) 78 phy_print_status(phy_dev); 79 } 80 81 /** 82 * arc_emac_get_drvinfo - Get EMAC driver information. 83 * @ndev: Pointer to net_device structure. 84 * @info: Pointer to ethtool_drvinfo structure. 85 * 86 * This implements ethtool command for getting the driver information. 87 * Issue "ethtool -i ethX" under linux prompt to execute this function. 88 */ 89 static void arc_emac_get_drvinfo(struct net_device *ndev, 90 struct ethtool_drvinfo *info) 91 { 92 struct arc_emac_priv *priv = netdev_priv(ndev); 93 94 strscpy(info->driver, priv->drv_name, sizeof(info->driver)); 95 } 96 97 static const struct ethtool_ops arc_emac_ethtool_ops = { 98 .get_drvinfo = arc_emac_get_drvinfo, 99 .get_link = ethtool_op_get_link, 100 .get_link_ksettings = phy_ethtool_get_link_ksettings, 101 .set_link_ksettings = phy_ethtool_set_link_ksettings, 102 }; 103 104 #define FIRST_OR_LAST_MASK (FIRST_MASK | LAST_MASK) 105 106 /** 107 * arc_emac_tx_clean - clears processed by EMAC Tx BDs. 108 * @ndev: Pointer to the network device. 109 */ 110 static void arc_emac_tx_clean(struct net_device *ndev) 111 { 112 struct arc_emac_priv *priv = netdev_priv(ndev); 113 struct net_device_stats *stats = &ndev->stats; 114 unsigned int i; 115 116 for (i = 0; i < TX_BD_NUM; i++) { 117 unsigned int *txbd_dirty = &priv->txbd_dirty; 118 struct arc_emac_bd *txbd = &priv->txbd[*txbd_dirty]; 119 struct buffer_state *tx_buff = &priv->tx_buff[*txbd_dirty]; 120 struct sk_buff *skb = tx_buff->skb; 121 unsigned int info = le32_to_cpu(txbd->info); 122 123 if ((info & FOR_EMAC) || !txbd->data || !skb) 124 break; 125 126 if (unlikely(info & (DROP | DEFR | LTCL | UFLO))) { 127 stats->tx_errors++; 128 stats->tx_dropped++; 129 130 if (info & DEFR) 131 stats->tx_carrier_errors++; 132 133 if (info & LTCL) 134 stats->collisions++; 135 136 if (info & UFLO) 137 stats->tx_fifo_errors++; 138 } else if (likely(info & FIRST_OR_LAST_MASK)) { 139 stats->tx_packets++; 140 stats->tx_bytes += skb->len; 141 } 142 143 dma_unmap_single(&ndev->dev, dma_unmap_addr(tx_buff, addr), 144 dma_unmap_len(tx_buff, len), DMA_TO_DEVICE); 145 146 /* return the sk_buff to system */ 147 dev_consume_skb_irq(skb); 148 149 txbd->data = 0; 150 txbd->info = 0; 151 tx_buff->skb = NULL; 152 153 *txbd_dirty = (*txbd_dirty + 1) % TX_BD_NUM; 154 } 155 156 /* Ensure that txbd_dirty is visible to tx() before checking 157 * for queue stopped. 158 */ 159 smp_mb(); 160 161 if (netif_queue_stopped(ndev) && arc_emac_tx_avail(priv)) 162 netif_wake_queue(ndev); 163 } 164 165 /** 166 * arc_emac_rx - processing of Rx packets. 167 * @ndev: Pointer to the network device. 168 * @budget: How many BDs to process on 1 call. 169 * 170 * returns: Number of processed BDs 171 * 172 * Iterate through Rx BDs and deliver received packages to upper layer. 173 */ 174 static int arc_emac_rx(struct net_device *ndev, int budget) 175 { 176 struct arc_emac_priv *priv = netdev_priv(ndev); 177 unsigned int work_done; 178 179 for (work_done = 0; work_done < budget; work_done++) { 180 unsigned int *last_rx_bd = &priv->last_rx_bd; 181 struct net_device_stats *stats = &ndev->stats; 182 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd]; 183 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd]; 184 unsigned int pktlen, info = le32_to_cpu(rxbd->info); 185 struct sk_buff *skb; 186 dma_addr_t addr; 187 188 if (unlikely((info & OWN_MASK) == FOR_EMAC)) 189 break; 190 191 /* Make a note that we saw a packet at this BD. 192 * So next time, driver starts from this + 1 193 */ 194 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM; 195 196 if (unlikely((info & FIRST_OR_LAST_MASK) != 197 FIRST_OR_LAST_MASK)) { 198 /* We pre-allocate buffers of MTU size so incoming 199 * packets won't be split/chained. 200 */ 201 if (net_ratelimit()) 202 netdev_err(ndev, "incomplete packet received\n"); 203 204 /* Return ownership to EMAC */ 205 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 206 stats->rx_errors++; 207 stats->rx_length_errors++; 208 continue; 209 } 210 211 /* Prepare the BD for next cycle. netif_receive_skb() 212 * only if new skb was allocated and mapped to avoid holes 213 * in the RX fifo. 214 */ 215 skb = netdev_alloc_skb_ip_align(ndev, EMAC_BUFFER_SIZE); 216 if (unlikely(!skb)) { 217 if (net_ratelimit()) 218 netdev_err(ndev, "cannot allocate skb\n"); 219 /* Return ownership to EMAC */ 220 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 221 stats->rx_errors++; 222 stats->rx_dropped++; 223 continue; 224 } 225 226 addr = dma_map_single(&ndev->dev, (void *)skb->data, 227 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE); 228 if (dma_mapping_error(&ndev->dev, addr)) { 229 if (net_ratelimit()) 230 netdev_err(ndev, "cannot map dma buffer\n"); 231 dev_kfree_skb(skb); 232 /* Return ownership to EMAC */ 233 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 234 stats->rx_errors++; 235 stats->rx_dropped++; 236 continue; 237 } 238 239 /* unmap previosly mapped skb */ 240 dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr), 241 dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE); 242 243 pktlen = info & LEN_MASK; 244 stats->rx_packets++; 245 stats->rx_bytes += pktlen; 246 skb_put(rx_buff->skb, pktlen); 247 rx_buff->skb->dev = ndev; 248 rx_buff->skb->protocol = eth_type_trans(rx_buff->skb, ndev); 249 250 netif_receive_skb(rx_buff->skb); 251 252 rx_buff->skb = skb; 253 dma_unmap_addr_set(rx_buff, addr, addr); 254 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE); 255 256 rxbd->data = cpu_to_le32(addr); 257 258 /* Make sure pointer to data buffer is set */ 259 wmb(); 260 261 /* Return ownership to EMAC */ 262 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 263 } 264 265 return work_done; 266 } 267 268 /** 269 * arc_emac_rx_miss_handle - handle R_MISS register 270 * @ndev: Pointer to the net_device structure. 271 */ 272 static void arc_emac_rx_miss_handle(struct net_device *ndev) 273 { 274 struct arc_emac_priv *priv = netdev_priv(ndev); 275 struct net_device_stats *stats = &ndev->stats; 276 unsigned int miss; 277 278 miss = arc_reg_get(priv, R_MISS); 279 if (miss) { 280 stats->rx_errors += miss; 281 stats->rx_missed_errors += miss; 282 priv->rx_missed_errors += miss; 283 } 284 } 285 286 /** 287 * arc_emac_rx_stall_check - check RX stall 288 * @ndev: Pointer to the net_device structure. 289 * @budget: How many BDs requested to process on 1 call. 290 * @work_done: How many BDs processed 291 * 292 * Under certain conditions EMAC stop reception of incoming packets and 293 * continuously increment R_MISS register instead of saving data into 294 * provided buffer. This function detect that condition and restart 295 * EMAC. 296 */ 297 static void arc_emac_rx_stall_check(struct net_device *ndev, 298 int budget, unsigned int work_done) 299 { 300 struct arc_emac_priv *priv = netdev_priv(ndev); 301 struct arc_emac_bd *rxbd; 302 303 if (work_done) 304 priv->rx_missed_errors = 0; 305 306 if (priv->rx_missed_errors && budget) { 307 rxbd = &priv->rxbd[priv->last_rx_bd]; 308 if (le32_to_cpu(rxbd->info) & FOR_EMAC) { 309 arc_emac_restart(ndev); 310 priv->rx_missed_errors = 0; 311 } 312 } 313 } 314 315 /** 316 * arc_emac_poll - NAPI poll handler. 317 * @napi: Pointer to napi_struct structure. 318 * @budget: How many BDs to process on 1 call. 319 * 320 * returns: Number of processed BDs 321 */ 322 static int arc_emac_poll(struct napi_struct *napi, int budget) 323 { 324 struct net_device *ndev = napi->dev; 325 struct arc_emac_priv *priv = netdev_priv(ndev); 326 unsigned int work_done; 327 328 arc_emac_tx_clean(ndev); 329 arc_emac_rx_miss_handle(ndev); 330 331 work_done = arc_emac_rx(ndev, budget); 332 if (work_done < budget) { 333 napi_complete_done(napi, work_done); 334 arc_reg_or(priv, R_ENABLE, RXINT_MASK | TXINT_MASK); 335 } 336 337 arc_emac_rx_stall_check(ndev, budget, work_done); 338 339 return work_done; 340 } 341 342 /** 343 * arc_emac_intr - Global interrupt handler for EMAC. 344 * @irq: irq number. 345 * @dev_instance: device instance. 346 * 347 * returns: IRQ_HANDLED for all cases. 348 * 349 * ARC EMAC has only 1 interrupt line, and depending on bits raised in 350 * STATUS register we may tell what is a reason for interrupt to fire. 351 */ 352 static irqreturn_t arc_emac_intr(int irq, void *dev_instance) 353 { 354 struct net_device *ndev = dev_instance; 355 struct arc_emac_priv *priv = netdev_priv(ndev); 356 struct net_device_stats *stats = &ndev->stats; 357 unsigned int status; 358 359 status = arc_reg_get(priv, R_STATUS); 360 status &= ~MDIO_MASK; 361 362 /* Reset all flags except "MDIO complete" */ 363 arc_reg_set(priv, R_STATUS, status); 364 365 if (status & (RXINT_MASK | TXINT_MASK)) { 366 if (likely(napi_schedule_prep(&priv->napi))) { 367 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK); 368 __napi_schedule(&priv->napi); 369 } 370 } 371 372 if (status & ERR_MASK) { 373 /* MSER/RXCR/RXFR/RXFL interrupt fires on corresponding 374 * 8-bit error counter overrun. 375 */ 376 377 if (status & MSER_MASK) { 378 stats->rx_missed_errors += 0x100; 379 stats->rx_errors += 0x100; 380 priv->rx_missed_errors += 0x100; 381 napi_schedule(&priv->napi); 382 } 383 384 if (status & RXCR_MASK) { 385 stats->rx_crc_errors += 0x100; 386 stats->rx_errors += 0x100; 387 } 388 389 if (status & RXFR_MASK) { 390 stats->rx_frame_errors += 0x100; 391 stats->rx_errors += 0x100; 392 } 393 394 if (status & RXFL_MASK) { 395 stats->rx_over_errors += 0x100; 396 stats->rx_errors += 0x100; 397 } 398 } 399 400 return IRQ_HANDLED; 401 } 402 403 #ifdef CONFIG_NET_POLL_CONTROLLER 404 static void arc_emac_poll_controller(struct net_device *dev) 405 { 406 disable_irq(dev->irq); 407 arc_emac_intr(dev->irq, dev); 408 enable_irq(dev->irq); 409 } 410 #endif 411 412 /** 413 * arc_emac_open - Open the network device. 414 * @ndev: Pointer to the network device. 415 * 416 * returns: 0, on success or non-zero error value on failure. 417 * 418 * This function sets the MAC address, requests and enables an IRQ 419 * for the EMAC device and starts the Tx queue. 420 * It also connects to the phy device. 421 */ 422 static int arc_emac_open(struct net_device *ndev) 423 { 424 struct arc_emac_priv *priv = netdev_priv(ndev); 425 struct phy_device *phy_dev = ndev->phydev; 426 int i; 427 428 phy_dev->autoneg = AUTONEG_ENABLE; 429 phy_dev->speed = 0; 430 phy_dev->duplex = 0; 431 linkmode_and(phy_dev->advertising, phy_dev->advertising, 432 phy_dev->supported); 433 434 priv->last_rx_bd = 0; 435 436 /* Allocate and set buffers for Rx BD's */ 437 for (i = 0; i < RX_BD_NUM; i++) { 438 dma_addr_t addr; 439 unsigned int *last_rx_bd = &priv->last_rx_bd; 440 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd]; 441 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd]; 442 443 rx_buff->skb = netdev_alloc_skb_ip_align(ndev, 444 EMAC_BUFFER_SIZE); 445 if (unlikely(!rx_buff->skb)) 446 return -ENOMEM; 447 448 addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data, 449 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE); 450 if (dma_mapping_error(&ndev->dev, addr)) { 451 netdev_err(ndev, "cannot dma map\n"); 452 dev_kfree_skb(rx_buff->skb); 453 return -ENOMEM; 454 } 455 dma_unmap_addr_set(rx_buff, addr, addr); 456 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE); 457 458 rxbd->data = cpu_to_le32(addr); 459 460 /* Make sure pointer to data buffer is set */ 461 wmb(); 462 463 /* Return ownership to EMAC */ 464 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 465 466 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM; 467 } 468 469 priv->txbd_curr = 0; 470 priv->txbd_dirty = 0; 471 472 /* Clean Tx BD's */ 473 memset(priv->txbd, 0, TX_RING_SZ); 474 475 /* Initialize logical address filter */ 476 arc_reg_set(priv, R_LAFL, 0); 477 arc_reg_set(priv, R_LAFH, 0); 478 479 /* Set BD ring pointers for device side */ 480 arc_reg_set(priv, R_RX_RING, (unsigned int)priv->rxbd_dma); 481 arc_reg_set(priv, R_TX_RING, (unsigned int)priv->txbd_dma); 482 483 /* Enable interrupts */ 484 arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 485 486 /* Set CONTROL */ 487 arc_reg_set(priv, R_CTRL, 488 (RX_BD_NUM << 24) | /* RX BD table length */ 489 (TX_BD_NUM << 16) | /* TX BD table length */ 490 TXRN_MASK | RXRN_MASK); 491 492 napi_enable(&priv->napi); 493 494 /* Enable EMAC */ 495 arc_reg_or(priv, R_CTRL, EN_MASK); 496 497 phy_start(ndev->phydev); 498 499 netif_start_queue(ndev); 500 501 return 0; 502 } 503 504 /** 505 * arc_emac_set_rx_mode - Change the receive filtering mode. 506 * @ndev: Pointer to the network device. 507 * 508 * This function enables/disables promiscuous or all-multicast mode 509 * and updates the multicast filtering list of the network device. 510 */ 511 static void arc_emac_set_rx_mode(struct net_device *ndev) 512 { 513 struct arc_emac_priv *priv = netdev_priv(ndev); 514 515 if (ndev->flags & IFF_PROMISC) { 516 arc_reg_or(priv, R_CTRL, PROM_MASK); 517 } else { 518 arc_reg_clr(priv, R_CTRL, PROM_MASK); 519 520 if (ndev->flags & IFF_ALLMULTI) { 521 arc_reg_set(priv, R_LAFL, ~0); 522 arc_reg_set(priv, R_LAFH, ~0); 523 } else if (ndev->flags & IFF_MULTICAST) { 524 struct netdev_hw_addr *ha; 525 unsigned int filter[2] = { 0, 0 }; 526 int bit; 527 528 netdev_for_each_mc_addr(ha, ndev) { 529 bit = ether_crc_le(ETH_ALEN, ha->addr) >> 26; 530 filter[bit >> 5] |= 1 << (bit & 31); 531 } 532 533 arc_reg_set(priv, R_LAFL, filter[0]); 534 arc_reg_set(priv, R_LAFH, filter[1]); 535 } else { 536 arc_reg_set(priv, R_LAFL, 0); 537 arc_reg_set(priv, R_LAFH, 0); 538 } 539 } 540 } 541 542 /** 543 * arc_free_tx_queue - free skb from tx queue 544 * @ndev: Pointer to the network device. 545 * 546 * This function must be called while EMAC disable 547 */ 548 static void arc_free_tx_queue(struct net_device *ndev) 549 { 550 struct arc_emac_priv *priv = netdev_priv(ndev); 551 unsigned int i; 552 553 for (i = 0; i < TX_BD_NUM; i++) { 554 struct arc_emac_bd *txbd = &priv->txbd[i]; 555 struct buffer_state *tx_buff = &priv->tx_buff[i]; 556 557 if (tx_buff->skb) { 558 dma_unmap_single(&ndev->dev, 559 dma_unmap_addr(tx_buff, addr), 560 dma_unmap_len(tx_buff, len), 561 DMA_TO_DEVICE); 562 563 /* return the sk_buff to system */ 564 dev_kfree_skb_irq(tx_buff->skb); 565 } 566 567 txbd->info = 0; 568 txbd->data = 0; 569 tx_buff->skb = NULL; 570 } 571 } 572 573 /** 574 * arc_free_rx_queue - free skb from rx queue 575 * @ndev: Pointer to the network device. 576 * 577 * This function must be called while EMAC disable 578 */ 579 static void arc_free_rx_queue(struct net_device *ndev) 580 { 581 struct arc_emac_priv *priv = netdev_priv(ndev); 582 unsigned int i; 583 584 for (i = 0; i < RX_BD_NUM; i++) { 585 struct arc_emac_bd *rxbd = &priv->rxbd[i]; 586 struct buffer_state *rx_buff = &priv->rx_buff[i]; 587 588 if (rx_buff->skb) { 589 dma_unmap_single(&ndev->dev, 590 dma_unmap_addr(rx_buff, addr), 591 dma_unmap_len(rx_buff, len), 592 DMA_FROM_DEVICE); 593 594 /* return the sk_buff to system */ 595 dev_kfree_skb_irq(rx_buff->skb); 596 } 597 598 rxbd->info = 0; 599 rxbd->data = 0; 600 rx_buff->skb = NULL; 601 } 602 } 603 604 /** 605 * arc_emac_stop - Close the network device. 606 * @ndev: Pointer to the network device. 607 * 608 * This function stops the Tx queue, disables interrupts and frees the IRQ for 609 * the EMAC device. 610 * It also disconnects the PHY device associated with the EMAC device. 611 */ 612 static int arc_emac_stop(struct net_device *ndev) 613 { 614 struct arc_emac_priv *priv = netdev_priv(ndev); 615 616 napi_disable(&priv->napi); 617 netif_stop_queue(ndev); 618 619 phy_stop(ndev->phydev); 620 621 /* Disable interrupts */ 622 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 623 624 /* Disable EMAC */ 625 arc_reg_clr(priv, R_CTRL, EN_MASK); 626 627 /* Return the sk_buff to system */ 628 arc_free_tx_queue(ndev); 629 arc_free_rx_queue(ndev); 630 631 return 0; 632 } 633 634 /** 635 * arc_emac_stats - Get system network statistics. 636 * @ndev: Pointer to net_device structure. 637 * 638 * Returns the address of the device statistics structure. 639 * Statistics are updated in interrupt handler. 640 */ 641 static struct net_device_stats *arc_emac_stats(struct net_device *ndev) 642 { 643 struct arc_emac_priv *priv = netdev_priv(ndev); 644 struct net_device_stats *stats = &ndev->stats; 645 unsigned long miss, rxerr; 646 u8 rxcrc, rxfram, rxoflow; 647 648 rxerr = arc_reg_get(priv, R_RXERR); 649 miss = arc_reg_get(priv, R_MISS); 650 651 rxcrc = rxerr; 652 rxfram = rxerr >> 8; 653 rxoflow = rxerr >> 16; 654 655 stats->rx_errors += miss; 656 stats->rx_errors += rxcrc + rxfram + rxoflow; 657 658 stats->rx_over_errors += rxoflow; 659 stats->rx_frame_errors += rxfram; 660 stats->rx_crc_errors += rxcrc; 661 stats->rx_missed_errors += miss; 662 663 return stats; 664 } 665 666 /** 667 * arc_emac_tx - Starts the data transmission. 668 * @skb: sk_buff pointer that contains data to be Transmitted. 669 * @ndev: Pointer to net_device structure. 670 * 671 * returns: NETDEV_TX_OK, on success 672 * NETDEV_TX_BUSY, if any of the descriptors are not free. 673 * 674 * This function is invoked from upper layers to initiate transmission. 675 */ 676 static netdev_tx_t arc_emac_tx(struct sk_buff *skb, struct net_device *ndev) 677 { 678 struct arc_emac_priv *priv = netdev_priv(ndev); 679 unsigned int len, *txbd_curr = &priv->txbd_curr; 680 struct net_device_stats *stats = &ndev->stats; 681 __le32 *info = &priv->txbd[*txbd_curr].info; 682 dma_addr_t addr; 683 684 if (skb_padto(skb, ETH_ZLEN)) 685 return NETDEV_TX_OK; 686 687 len = max_t(unsigned int, ETH_ZLEN, skb->len); 688 689 if (unlikely(!arc_emac_tx_avail(priv))) { 690 netif_stop_queue(ndev); 691 netdev_err(ndev, "BUG! Tx Ring full when queue awake!\n"); 692 return NETDEV_TX_BUSY; 693 } 694 695 addr = dma_map_single(&ndev->dev, (void *)skb->data, len, 696 DMA_TO_DEVICE); 697 698 if (unlikely(dma_mapping_error(&ndev->dev, addr))) { 699 stats->tx_dropped++; 700 stats->tx_errors++; 701 dev_kfree_skb_any(skb); 702 return NETDEV_TX_OK; 703 } 704 dma_unmap_addr_set(&priv->tx_buff[*txbd_curr], addr, addr); 705 dma_unmap_len_set(&priv->tx_buff[*txbd_curr], len, len); 706 707 priv->txbd[*txbd_curr].data = cpu_to_le32(addr); 708 709 /* Make sure pointer to data buffer is set */ 710 wmb(); 711 712 skb_tx_timestamp(skb); 713 714 *info = cpu_to_le32(FOR_EMAC | FIRST_OR_LAST_MASK | len); 715 716 /* Make sure info word is set */ 717 wmb(); 718 719 priv->tx_buff[*txbd_curr].skb = skb; 720 721 /* Increment index to point to the next BD */ 722 *txbd_curr = (*txbd_curr + 1) % TX_BD_NUM; 723 724 /* Ensure that tx_clean() sees the new txbd_curr before 725 * checking the queue status. This prevents an unneeded wake 726 * of the queue in tx_clean(). 727 */ 728 smp_mb(); 729 730 if (!arc_emac_tx_avail(priv)) { 731 netif_stop_queue(ndev); 732 /* Refresh tx_dirty */ 733 smp_mb(); 734 if (arc_emac_tx_avail(priv)) 735 netif_start_queue(ndev); 736 } 737 738 arc_reg_set(priv, R_STATUS, TXPL_MASK); 739 740 return NETDEV_TX_OK; 741 } 742 743 static void arc_emac_set_address_internal(struct net_device *ndev) 744 { 745 struct arc_emac_priv *priv = netdev_priv(ndev); 746 unsigned int addr_low, addr_hi; 747 748 addr_low = le32_to_cpu(*(__le32 *)&ndev->dev_addr[0]); 749 addr_hi = le16_to_cpu(*(__le16 *)&ndev->dev_addr[4]); 750 751 arc_reg_set(priv, R_ADDRL, addr_low); 752 arc_reg_set(priv, R_ADDRH, addr_hi); 753 } 754 755 /** 756 * arc_emac_set_address - Set the MAC address for this device. 757 * @ndev: Pointer to net_device structure. 758 * @p: 6 byte Address to be written as MAC address. 759 * 760 * This function copies the HW address from the sockaddr structure to the 761 * net_device structure and updates the address in HW. 762 * 763 * returns: -EBUSY if the net device is busy or 0 if the address is set 764 * successfully. 765 */ 766 static int arc_emac_set_address(struct net_device *ndev, void *p) 767 { 768 struct sockaddr *addr = p; 769 770 if (netif_running(ndev)) 771 return -EBUSY; 772 773 if (!is_valid_ether_addr(addr->sa_data)) 774 return -EADDRNOTAVAIL; 775 776 eth_hw_addr_set(ndev, addr->sa_data); 777 778 arc_emac_set_address_internal(ndev); 779 780 return 0; 781 } 782 783 /** 784 * arc_emac_restart - Restart EMAC 785 * @ndev: Pointer to net_device structure. 786 * 787 * This function do hardware reset of EMAC in order to restore 788 * network packets reception. 789 */ 790 static void arc_emac_restart(struct net_device *ndev) 791 { 792 struct arc_emac_priv *priv = netdev_priv(ndev); 793 struct net_device_stats *stats = &ndev->stats; 794 int i; 795 796 if (net_ratelimit()) 797 netdev_warn(ndev, "restarting stalled EMAC\n"); 798 799 netif_stop_queue(ndev); 800 801 /* Disable interrupts */ 802 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 803 804 /* Disable EMAC */ 805 arc_reg_clr(priv, R_CTRL, EN_MASK); 806 807 /* Return the sk_buff to system */ 808 arc_free_tx_queue(ndev); 809 810 /* Clean Tx BD's */ 811 priv->txbd_curr = 0; 812 priv->txbd_dirty = 0; 813 memset(priv->txbd, 0, TX_RING_SZ); 814 815 for (i = 0; i < RX_BD_NUM; i++) { 816 struct arc_emac_bd *rxbd = &priv->rxbd[i]; 817 unsigned int info = le32_to_cpu(rxbd->info); 818 819 if (!(info & FOR_EMAC)) { 820 stats->rx_errors++; 821 stats->rx_dropped++; 822 } 823 /* Return ownership to EMAC */ 824 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 825 } 826 priv->last_rx_bd = 0; 827 828 /* Make sure info is visible to EMAC before enable */ 829 wmb(); 830 831 /* Enable interrupts */ 832 arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 833 834 /* Enable EMAC */ 835 arc_reg_or(priv, R_CTRL, EN_MASK); 836 837 netif_start_queue(ndev); 838 } 839 840 static const struct net_device_ops arc_emac_netdev_ops = { 841 .ndo_open = arc_emac_open, 842 .ndo_stop = arc_emac_stop, 843 .ndo_start_xmit = arc_emac_tx, 844 .ndo_set_mac_address = arc_emac_set_address, 845 .ndo_get_stats = arc_emac_stats, 846 .ndo_set_rx_mode = arc_emac_set_rx_mode, 847 .ndo_eth_ioctl = phy_do_ioctl_running, 848 #ifdef CONFIG_NET_POLL_CONTROLLER 849 .ndo_poll_controller = arc_emac_poll_controller, 850 #endif 851 }; 852 853 int arc_emac_probe(struct net_device *ndev, int interface) 854 { 855 struct device *dev = ndev->dev.parent; 856 struct resource res_regs; 857 struct device_node *phy_node; 858 struct phy_device *phydev = NULL; 859 struct arc_emac_priv *priv; 860 unsigned int id, clock_frequency, irq; 861 int err; 862 863 /* Get PHY from device tree */ 864 phy_node = of_parse_phandle(dev->of_node, "phy", 0); 865 if (!phy_node) { 866 dev_err(dev, "failed to retrieve phy description from device tree\n"); 867 return -ENODEV; 868 } 869 870 /* Get EMAC registers base address from device tree */ 871 err = of_address_to_resource(dev->of_node, 0, &res_regs); 872 if (err) { 873 dev_err(dev, "failed to retrieve registers base from device tree\n"); 874 err = -ENODEV; 875 goto out_put_node; 876 } 877 878 /* Get IRQ from device tree */ 879 irq = irq_of_parse_and_map(dev->of_node, 0); 880 if (!irq) { 881 dev_err(dev, "failed to retrieve <irq> value from device tree\n"); 882 err = -ENODEV; 883 goto out_put_node; 884 } 885 886 ndev->netdev_ops = &arc_emac_netdev_ops; 887 ndev->ethtool_ops = &arc_emac_ethtool_ops; 888 ndev->watchdog_timeo = TX_TIMEOUT; 889 890 priv = netdev_priv(ndev); 891 priv->dev = dev; 892 893 priv->regs = devm_ioremap_resource(dev, &res_regs); 894 if (IS_ERR(priv->regs)) { 895 err = PTR_ERR(priv->regs); 896 goto out_put_node; 897 } 898 899 dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs); 900 901 if (priv->clk) { 902 err = clk_prepare_enable(priv->clk); 903 if (err) { 904 dev_err(dev, "failed to enable clock\n"); 905 goto out_put_node; 906 } 907 908 clock_frequency = clk_get_rate(priv->clk); 909 } else { 910 /* Get CPU clock frequency from device tree */ 911 if (of_property_read_u32(dev->of_node, "clock-frequency", 912 &clock_frequency)) { 913 dev_err(dev, "failed to retrieve <clock-frequency> from device tree\n"); 914 err = -EINVAL; 915 goto out_put_node; 916 } 917 } 918 919 id = arc_reg_get(priv, R_ID); 920 921 /* Check for EMAC revision 5 or 7, magic number */ 922 if (!(id == 0x0005fd02 || id == 0x0007fd02)) { 923 dev_err(dev, "ARC EMAC not detected, id=0x%x\n", id); 924 err = -ENODEV; 925 goto out_clken; 926 } 927 dev_info(dev, "ARC EMAC detected with id: 0x%x\n", id); 928 929 /* Set poll rate so that it polls every 1 ms */ 930 arc_reg_set(priv, R_POLLRATE, clock_frequency / 1000000); 931 932 ndev->irq = irq; 933 dev_info(dev, "IRQ is %d\n", ndev->irq); 934 935 /* Register interrupt handler for device */ 936 err = devm_request_irq(dev, ndev->irq, arc_emac_intr, 0, 937 ndev->name, ndev); 938 if (err) { 939 dev_err(dev, "could not allocate IRQ\n"); 940 goto out_clken; 941 } 942 943 /* Get MAC address from device tree */ 944 err = of_get_ethdev_address(dev->of_node, ndev); 945 if (err) 946 eth_hw_addr_random(ndev); 947 948 arc_emac_set_address_internal(ndev); 949 dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr); 950 951 /* Do 1 allocation instead of 2 separate ones for Rx and Tx BD rings */ 952 priv->rxbd = dmam_alloc_coherent(dev, RX_RING_SZ + TX_RING_SZ, 953 &priv->rxbd_dma, GFP_KERNEL); 954 955 if (!priv->rxbd) { 956 dev_err(dev, "failed to allocate data buffers\n"); 957 err = -ENOMEM; 958 goto out_clken; 959 } 960 961 priv->txbd = priv->rxbd + RX_BD_NUM; 962 963 priv->txbd_dma = priv->rxbd_dma + RX_RING_SZ; 964 dev_dbg(dev, "EMAC Device addr: Rx Ring [0x%x], Tx Ring[%x]\n", 965 (unsigned int)priv->rxbd_dma, (unsigned int)priv->txbd_dma); 966 967 err = arc_mdio_probe(priv); 968 if (err) { 969 dev_err(dev, "failed to probe MII bus\n"); 970 goto out_clken; 971 } 972 973 phydev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0, 974 interface); 975 if (!phydev) { 976 dev_err(dev, "of_phy_connect() failed\n"); 977 err = -ENODEV; 978 goto out_mdio; 979 } 980 981 dev_info(dev, "connected to %s phy with id 0x%x\n", 982 phydev->drv->name, phydev->phy_id); 983 984 netif_napi_add_weight(ndev, &priv->napi, arc_emac_poll, 985 ARC_EMAC_NAPI_WEIGHT); 986 987 err = register_netdev(ndev); 988 if (err) { 989 dev_err(dev, "failed to register network device\n"); 990 goto out_netif_api; 991 } 992 993 of_node_put(phy_node); 994 return 0; 995 996 out_netif_api: 997 netif_napi_del(&priv->napi); 998 phy_disconnect(phydev); 999 out_mdio: 1000 arc_mdio_remove(priv); 1001 out_clken: 1002 if (priv->clk) 1003 clk_disable_unprepare(priv->clk); 1004 out_put_node: 1005 of_node_put(phy_node); 1006 1007 return err; 1008 } 1009 EXPORT_SYMBOL_GPL(arc_emac_probe); 1010 1011 void arc_emac_remove(struct net_device *ndev) 1012 { 1013 struct arc_emac_priv *priv = netdev_priv(ndev); 1014 1015 phy_disconnect(ndev->phydev); 1016 arc_mdio_remove(priv); 1017 unregister_netdev(ndev); 1018 netif_napi_del(&priv->napi); 1019 1020 if (!IS_ERR(priv->clk)) 1021 clk_disable_unprepare(priv->clk); 1022 } 1023 EXPORT_SYMBOL_GPL(arc_emac_remove); 1024 1025 MODULE_AUTHOR("Alexey Brodkin <abrodkin@synopsys.com>"); 1026 MODULE_DESCRIPTION("ARC EMAC driver"); 1027 MODULE_LICENSE("GPL"); 1028