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_address.h> 19 #include <linux/of_irq.h> 20 #include <linux/of_mdio.h> 21 #include <linux/of_net.h> 22 #include <linux/of_platform.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 strlcpy(info->driver, priv->drv_name, sizeof(info->driver)); 95 strlcpy(info->version, priv->drv_version, sizeof(info->version)); 96 } 97 98 static const struct ethtool_ops arc_emac_ethtool_ops = { 99 .get_drvinfo = arc_emac_get_drvinfo, 100 .get_link = ethtool_op_get_link, 101 .get_link_ksettings = phy_ethtool_get_link_ksettings, 102 .set_link_ksettings = phy_ethtool_set_link_ksettings, 103 }; 104 105 #define FIRST_OR_LAST_MASK (FIRST_MASK | LAST_MASK) 106 107 /** 108 * arc_emac_tx_clean - clears processed by EMAC Tx BDs. 109 * @ndev: Pointer to the network device. 110 */ 111 static void arc_emac_tx_clean(struct net_device *ndev) 112 { 113 struct arc_emac_priv *priv = netdev_priv(ndev); 114 struct net_device_stats *stats = &ndev->stats; 115 unsigned int i; 116 117 for (i = 0; i < TX_BD_NUM; i++) { 118 unsigned int *txbd_dirty = &priv->txbd_dirty; 119 struct arc_emac_bd *txbd = &priv->txbd[*txbd_dirty]; 120 struct buffer_state *tx_buff = &priv->tx_buff[*txbd_dirty]; 121 struct sk_buff *skb = tx_buff->skb; 122 unsigned int info = le32_to_cpu(txbd->info); 123 124 if ((info & FOR_EMAC) || !txbd->data || !skb) 125 break; 126 127 if (unlikely(info & (DROP | DEFR | LTCL | UFLO))) { 128 stats->tx_errors++; 129 stats->tx_dropped++; 130 131 if (info & DEFR) 132 stats->tx_carrier_errors++; 133 134 if (info & LTCL) 135 stats->collisions++; 136 137 if (info & UFLO) 138 stats->tx_fifo_errors++; 139 } else if (likely(info & FIRST_OR_LAST_MASK)) { 140 stats->tx_packets++; 141 stats->tx_bytes += skb->len; 142 } 143 144 dma_unmap_single(&ndev->dev, dma_unmap_addr(tx_buff, addr), 145 dma_unmap_len(tx_buff, len), DMA_TO_DEVICE); 146 147 /* return the sk_buff to system */ 148 dev_consume_skb_irq(skb); 149 150 txbd->data = 0; 151 txbd->info = 0; 152 tx_buff->skb = NULL; 153 154 *txbd_dirty = (*txbd_dirty + 1) % TX_BD_NUM; 155 } 156 157 /* Ensure that txbd_dirty is visible to tx() before checking 158 * for queue stopped. 159 */ 160 smp_mb(); 161 162 if (netif_queue_stopped(ndev) && arc_emac_tx_avail(priv)) 163 netif_wake_queue(ndev); 164 } 165 166 /** 167 * arc_emac_rx - processing of Rx packets. 168 * @ndev: Pointer to the network device. 169 * @budget: How many BDs to process on 1 call. 170 * 171 * returns: Number of processed BDs 172 * 173 * Iterate through Rx BDs and deliver received packages to upper layer. 174 */ 175 static int arc_emac_rx(struct net_device *ndev, int budget) 176 { 177 struct arc_emac_priv *priv = netdev_priv(ndev); 178 unsigned int work_done; 179 180 for (work_done = 0; work_done < budget; work_done++) { 181 unsigned int *last_rx_bd = &priv->last_rx_bd; 182 struct net_device_stats *stats = &ndev->stats; 183 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd]; 184 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd]; 185 unsigned int pktlen, info = le32_to_cpu(rxbd->info); 186 struct sk_buff *skb; 187 dma_addr_t addr; 188 189 if (unlikely((info & OWN_MASK) == FOR_EMAC)) 190 break; 191 192 /* Make a note that we saw a packet at this BD. 193 * So next time, driver starts from this + 1 194 */ 195 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM; 196 197 if (unlikely((info & FIRST_OR_LAST_MASK) != 198 FIRST_OR_LAST_MASK)) { 199 /* We pre-allocate buffers of MTU size so incoming 200 * packets won't be split/chained. 201 */ 202 if (net_ratelimit()) 203 netdev_err(ndev, "incomplete packet received\n"); 204 205 /* Return ownership to EMAC */ 206 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 207 stats->rx_errors++; 208 stats->rx_length_errors++; 209 continue; 210 } 211 212 /* Prepare the BD for next cycle. netif_receive_skb() 213 * only if new skb was allocated and mapped to avoid holes 214 * in the RX fifo. 215 */ 216 skb = netdev_alloc_skb_ip_align(ndev, EMAC_BUFFER_SIZE); 217 if (unlikely(!skb)) { 218 if (net_ratelimit()) 219 netdev_err(ndev, "cannot allocate skb\n"); 220 /* Return ownership to EMAC */ 221 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 222 stats->rx_errors++; 223 stats->rx_dropped++; 224 continue; 225 } 226 227 addr = dma_map_single(&ndev->dev, (void *)skb->data, 228 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE); 229 if (dma_mapping_error(&ndev->dev, addr)) { 230 if (net_ratelimit()) 231 netdev_err(ndev, "cannot map dma buffer\n"); 232 dev_kfree_skb(skb); 233 /* Return ownership to EMAC */ 234 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 235 stats->rx_errors++; 236 stats->rx_dropped++; 237 continue; 238 } 239 240 /* unmap previosly mapped skb */ 241 dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr), 242 dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE); 243 244 pktlen = info & LEN_MASK; 245 stats->rx_packets++; 246 stats->rx_bytes += pktlen; 247 skb_put(rx_buff->skb, pktlen); 248 rx_buff->skb->dev = ndev; 249 rx_buff->skb->protocol = eth_type_trans(rx_buff->skb, ndev); 250 251 netif_receive_skb(rx_buff->skb); 252 253 rx_buff->skb = skb; 254 dma_unmap_addr_set(rx_buff, addr, addr); 255 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE); 256 257 rxbd->data = cpu_to_le32(addr); 258 259 /* Make sure pointer to data buffer is set */ 260 wmb(); 261 262 /* Return ownership to EMAC */ 263 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 264 } 265 266 return work_done; 267 } 268 269 /** 270 * arc_emac_rx_miss_handle - handle R_MISS register 271 * @ndev: Pointer to the net_device structure. 272 */ 273 static void arc_emac_rx_miss_handle(struct net_device *ndev) 274 { 275 struct arc_emac_priv *priv = netdev_priv(ndev); 276 struct net_device_stats *stats = &ndev->stats; 277 unsigned int miss; 278 279 miss = arc_reg_get(priv, R_MISS); 280 if (miss) { 281 stats->rx_errors += miss; 282 stats->rx_missed_errors += miss; 283 priv->rx_missed_errors += miss; 284 } 285 } 286 287 /** 288 * arc_emac_rx_stall_check - check RX stall 289 * @ndev: Pointer to the net_device structure. 290 * @budget: How many BDs requested to process on 1 call. 291 * @work_done: How many BDs processed 292 * 293 * Under certain conditions EMAC stop reception of incoming packets and 294 * continuously increment R_MISS register instead of saving data into 295 * provided buffer. This function detect that condition and restart 296 * EMAC. 297 */ 298 static void arc_emac_rx_stall_check(struct net_device *ndev, 299 int budget, unsigned int work_done) 300 { 301 struct arc_emac_priv *priv = netdev_priv(ndev); 302 struct arc_emac_bd *rxbd; 303 304 if (work_done) 305 priv->rx_missed_errors = 0; 306 307 if (priv->rx_missed_errors && budget) { 308 rxbd = &priv->rxbd[priv->last_rx_bd]; 309 if (le32_to_cpu(rxbd->info) & FOR_EMAC) { 310 arc_emac_restart(ndev); 311 priv->rx_missed_errors = 0; 312 } 313 } 314 } 315 316 /** 317 * arc_emac_poll - NAPI poll handler. 318 * @napi: Pointer to napi_struct structure. 319 * @budget: How many BDs to process on 1 call. 320 * 321 * returns: Number of processed BDs 322 */ 323 static int arc_emac_poll(struct napi_struct *napi, int budget) 324 { 325 struct net_device *ndev = napi->dev; 326 struct arc_emac_priv *priv = netdev_priv(ndev); 327 unsigned int work_done; 328 329 arc_emac_tx_clean(ndev); 330 arc_emac_rx_miss_handle(ndev); 331 332 work_done = arc_emac_rx(ndev, budget); 333 if (work_done < budget) { 334 napi_complete_done(napi, work_done); 335 arc_reg_or(priv, R_ENABLE, RXINT_MASK | TXINT_MASK); 336 } 337 338 arc_emac_rx_stall_check(ndev, budget, work_done); 339 340 return work_done; 341 } 342 343 /** 344 * arc_emac_intr - Global interrupt handler for EMAC. 345 * @irq: irq number. 346 * @dev_instance: device instance. 347 * 348 * returns: IRQ_HANDLED for all cases. 349 * 350 * ARC EMAC has only 1 interrupt line, and depending on bits raised in 351 * STATUS register we may tell what is a reason for interrupt to fire. 352 */ 353 static irqreturn_t arc_emac_intr(int irq, void *dev_instance) 354 { 355 struct net_device *ndev = dev_instance; 356 struct arc_emac_priv *priv = netdev_priv(ndev); 357 struct net_device_stats *stats = &ndev->stats; 358 unsigned int status; 359 360 status = arc_reg_get(priv, R_STATUS); 361 status &= ~MDIO_MASK; 362 363 /* Reset all flags except "MDIO complete" */ 364 arc_reg_set(priv, R_STATUS, status); 365 366 if (status & (RXINT_MASK | TXINT_MASK)) { 367 if (likely(napi_schedule_prep(&priv->napi))) { 368 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK); 369 __napi_schedule(&priv->napi); 370 } 371 } 372 373 if (status & ERR_MASK) { 374 /* MSER/RXCR/RXFR/RXFL interrupt fires on corresponding 375 * 8-bit error counter overrun. 376 */ 377 378 if (status & MSER_MASK) { 379 stats->rx_missed_errors += 0x100; 380 stats->rx_errors += 0x100; 381 priv->rx_missed_errors += 0x100; 382 napi_schedule(&priv->napi); 383 } 384 385 if (status & RXCR_MASK) { 386 stats->rx_crc_errors += 0x100; 387 stats->rx_errors += 0x100; 388 } 389 390 if (status & RXFR_MASK) { 391 stats->rx_frame_errors += 0x100; 392 stats->rx_errors += 0x100; 393 } 394 395 if (status & RXFL_MASK) { 396 stats->rx_over_errors += 0x100; 397 stats->rx_errors += 0x100; 398 } 399 } 400 401 return IRQ_HANDLED; 402 } 403 404 #ifdef CONFIG_NET_POLL_CONTROLLER 405 static void arc_emac_poll_controller(struct net_device *dev) 406 { 407 disable_irq(dev->irq); 408 arc_emac_intr(dev->irq, dev); 409 enable_irq(dev->irq); 410 } 411 #endif 412 413 /** 414 * arc_emac_open - Open the network device. 415 * @ndev: Pointer to the network device. 416 * 417 * returns: 0, on success or non-zero error value on failure. 418 * 419 * This function sets the MAC address, requests and enables an IRQ 420 * for the EMAC device and starts the Tx queue. 421 * It also connects to the phy device. 422 */ 423 static int arc_emac_open(struct net_device *ndev) 424 { 425 struct arc_emac_priv *priv = netdev_priv(ndev); 426 struct phy_device *phy_dev = ndev->phydev; 427 int i; 428 429 phy_dev->autoneg = AUTONEG_ENABLE; 430 phy_dev->speed = 0; 431 phy_dev->duplex = 0; 432 linkmode_and(phy_dev->advertising, phy_dev->advertising, 433 phy_dev->supported); 434 435 priv->last_rx_bd = 0; 436 437 /* Allocate and set buffers for Rx BD's */ 438 for (i = 0; i < RX_BD_NUM; i++) { 439 dma_addr_t addr; 440 unsigned int *last_rx_bd = &priv->last_rx_bd; 441 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd]; 442 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd]; 443 444 rx_buff->skb = netdev_alloc_skb_ip_align(ndev, 445 EMAC_BUFFER_SIZE); 446 if (unlikely(!rx_buff->skb)) 447 return -ENOMEM; 448 449 addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data, 450 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE); 451 if (dma_mapping_error(&ndev->dev, addr)) { 452 netdev_err(ndev, "cannot dma map\n"); 453 dev_kfree_skb(rx_buff->skb); 454 return -ENOMEM; 455 } 456 dma_unmap_addr_set(rx_buff, addr, addr); 457 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE); 458 459 rxbd->data = cpu_to_le32(addr); 460 461 /* Make sure pointer to data buffer is set */ 462 wmb(); 463 464 /* Return ownership to EMAC */ 465 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 466 467 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM; 468 } 469 470 priv->txbd_curr = 0; 471 priv->txbd_dirty = 0; 472 473 /* Clean Tx BD's */ 474 memset(priv->txbd, 0, TX_RING_SZ); 475 476 /* Initialize logical address filter */ 477 arc_reg_set(priv, R_LAFL, 0); 478 arc_reg_set(priv, R_LAFH, 0); 479 480 /* Set BD ring pointers for device side */ 481 arc_reg_set(priv, R_RX_RING, (unsigned int)priv->rxbd_dma); 482 arc_reg_set(priv, R_TX_RING, (unsigned int)priv->txbd_dma); 483 484 /* Enable interrupts */ 485 arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 486 487 /* Set CONTROL */ 488 arc_reg_set(priv, R_CTRL, 489 (RX_BD_NUM << 24) | /* RX BD table length */ 490 (TX_BD_NUM << 16) | /* TX BD table length */ 491 TXRN_MASK | RXRN_MASK); 492 493 napi_enable(&priv->napi); 494 495 /* Enable EMAC */ 496 arc_reg_or(priv, R_CTRL, EN_MASK); 497 498 phy_start(ndev->phydev); 499 500 netif_start_queue(ndev); 501 502 return 0; 503 } 504 505 /** 506 * arc_emac_set_rx_mode - Change the receive filtering mode. 507 * @ndev: Pointer to the network device. 508 * 509 * This function enables/disables promiscuous or all-multicast mode 510 * and updates the multicast filtering list of the network device. 511 */ 512 static void arc_emac_set_rx_mode(struct net_device *ndev) 513 { 514 struct arc_emac_priv *priv = netdev_priv(ndev); 515 516 if (ndev->flags & IFF_PROMISC) { 517 arc_reg_or(priv, R_CTRL, PROM_MASK); 518 } else { 519 arc_reg_clr(priv, R_CTRL, PROM_MASK); 520 521 if (ndev->flags & IFF_ALLMULTI) { 522 arc_reg_set(priv, R_LAFL, ~0); 523 arc_reg_set(priv, R_LAFH, ~0); 524 } else if (ndev->flags & IFF_MULTICAST) { 525 struct netdev_hw_addr *ha; 526 unsigned int filter[2] = { 0, 0 }; 527 int bit; 528 529 netdev_for_each_mc_addr(ha, ndev) { 530 bit = ether_crc_le(ETH_ALEN, ha->addr) >> 26; 531 filter[bit >> 5] |= 1 << (bit & 31); 532 } 533 534 arc_reg_set(priv, R_LAFL, filter[0]); 535 arc_reg_set(priv, R_LAFH, filter[1]); 536 } else { 537 arc_reg_set(priv, R_LAFL, 0); 538 arc_reg_set(priv, R_LAFH, 0); 539 } 540 } 541 } 542 543 /** 544 * arc_free_tx_queue - free skb from tx queue 545 * @ndev: Pointer to the network device. 546 * 547 * This function must be called while EMAC disable 548 */ 549 static void arc_free_tx_queue(struct net_device *ndev) 550 { 551 struct arc_emac_priv *priv = netdev_priv(ndev); 552 unsigned int i; 553 554 for (i = 0; i < TX_BD_NUM; i++) { 555 struct arc_emac_bd *txbd = &priv->txbd[i]; 556 struct buffer_state *tx_buff = &priv->tx_buff[i]; 557 558 if (tx_buff->skb) { 559 dma_unmap_single(&ndev->dev, 560 dma_unmap_addr(tx_buff, addr), 561 dma_unmap_len(tx_buff, len), 562 DMA_TO_DEVICE); 563 564 /* return the sk_buff to system */ 565 dev_kfree_skb_irq(tx_buff->skb); 566 } 567 568 txbd->info = 0; 569 txbd->data = 0; 570 tx_buff->skb = NULL; 571 } 572 } 573 574 /** 575 * arc_free_rx_queue - free skb from rx queue 576 * @ndev: Pointer to the network device. 577 * 578 * This function must be called while EMAC disable 579 */ 580 static void arc_free_rx_queue(struct net_device *ndev) 581 { 582 struct arc_emac_priv *priv = netdev_priv(ndev); 583 unsigned int i; 584 585 for (i = 0; i < RX_BD_NUM; i++) { 586 struct arc_emac_bd *rxbd = &priv->rxbd[i]; 587 struct buffer_state *rx_buff = &priv->rx_buff[i]; 588 589 if (rx_buff->skb) { 590 dma_unmap_single(&ndev->dev, 591 dma_unmap_addr(rx_buff, addr), 592 dma_unmap_len(rx_buff, len), 593 DMA_FROM_DEVICE); 594 595 /* return the sk_buff to system */ 596 dev_kfree_skb_irq(rx_buff->skb); 597 } 598 599 rxbd->info = 0; 600 rxbd->data = 0; 601 rx_buff->skb = NULL; 602 } 603 } 604 605 /** 606 * arc_emac_stop - Close the network device. 607 * @ndev: Pointer to the network device. 608 * 609 * This function stops the Tx queue, disables interrupts and frees the IRQ for 610 * the EMAC device. 611 * It also disconnects the PHY device associated with the EMAC device. 612 */ 613 static int arc_emac_stop(struct net_device *ndev) 614 { 615 struct arc_emac_priv *priv = netdev_priv(ndev); 616 617 napi_disable(&priv->napi); 618 netif_stop_queue(ndev); 619 620 phy_stop(ndev->phydev); 621 622 /* Disable interrupts */ 623 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 624 625 /* Disable EMAC */ 626 arc_reg_clr(priv, R_CTRL, EN_MASK); 627 628 /* Return the sk_buff to system */ 629 arc_free_tx_queue(ndev); 630 arc_free_rx_queue(ndev); 631 632 return 0; 633 } 634 635 /** 636 * arc_emac_stats - Get system network statistics. 637 * @ndev: Pointer to net_device structure. 638 * 639 * Returns the address of the device statistics structure. 640 * Statistics are updated in interrupt handler. 641 */ 642 static struct net_device_stats *arc_emac_stats(struct net_device *ndev) 643 { 644 struct arc_emac_priv *priv = netdev_priv(ndev); 645 struct net_device_stats *stats = &ndev->stats; 646 unsigned long miss, rxerr; 647 u8 rxcrc, rxfram, rxoflow; 648 649 rxerr = arc_reg_get(priv, R_RXERR); 650 miss = arc_reg_get(priv, R_MISS); 651 652 rxcrc = rxerr; 653 rxfram = rxerr >> 8; 654 rxoflow = rxerr >> 16; 655 656 stats->rx_errors += miss; 657 stats->rx_errors += rxcrc + rxfram + rxoflow; 658 659 stats->rx_over_errors += rxoflow; 660 stats->rx_frame_errors += rxfram; 661 stats->rx_crc_errors += rxcrc; 662 stats->rx_missed_errors += miss; 663 664 return stats; 665 } 666 667 /** 668 * arc_emac_tx - Starts the data transmission. 669 * @skb: sk_buff pointer that contains data to be Transmitted. 670 * @ndev: Pointer to net_device structure. 671 * 672 * returns: NETDEV_TX_OK, on success 673 * NETDEV_TX_BUSY, if any of the descriptors are not free. 674 * 675 * This function is invoked from upper layers to initiate transmission. 676 */ 677 static int arc_emac_tx(struct sk_buff *skb, struct net_device *ndev) 678 { 679 struct arc_emac_priv *priv = netdev_priv(ndev); 680 unsigned int len, *txbd_curr = &priv->txbd_curr; 681 struct net_device_stats *stats = &ndev->stats; 682 __le32 *info = &priv->txbd[*txbd_curr].info; 683 dma_addr_t addr; 684 685 if (skb_padto(skb, ETH_ZLEN)) 686 return NETDEV_TX_OK; 687 688 len = max_t(unsigned int, ETH_ZLEN, skb->len); 689 690 if (unlikely(!arc_emac_tx_avail(priv))) { 691 netif_stop_queue(ndev); 692 netdev_err(ndev, "BUG! Tx Ring full when queue awake!\n"); 693 return NETDEV_TX_BUSY; 694 } 695 696 addr = dma_map_single(&ndev->dev, (void *)skb->data, len, 697 DMA_TO_DEVICE); 698 699 if (unlikely(dma_mapping_error(&ndev->dev, addr))) { 700 stats->tx_dropped++; 701 stats->tx_errors++; 702 dev_kfree_skb_any(skb); 703 return NETDEV_TX_OK; 704 } 705 dma_unmap_addr_set(&priv->tx_buff[*txbd_curr], addr, addr); 706 dma_unmap_len_set(&priv->tx_buff[*txbd_curr], len, len); 707 708 priv->txbd[*txbd_curr].data = cpu_to_le32(addr); 709 710 /* Make sure pointer to data buffer is set */ 711 wmb(); 712 713 skb_tx_timestamp(skb); 714 715 *info = cpu_to_le32(FOR_EMAC | FIRST_OR_LAST_MASK | len); 716 717 /* Make sure info word is set */ 718 wmb(); 719 720 priv->tx_buff[*txbd_curr].skb = skb; 721 722 /* Increment index to point to the next BD */ 723 *txbd_curr = (*txbd_curr + 1) % TX_BD_NUM; 724 725 /* Ensure that tx_clean() sees the new txbd_curr before 726 * checking the queue status. This prevents an unneeded wake 727 * of the queue in tx_clean(). 728 */ 729 smp_mb(); 730 731 if (!arc_emac_tx_avail(priv)) { 732 netif_stop_queue(ndev); 733 /* Refresh tx_dirty */ 734 smp_mb(); 735 if (arc_emac_tx_avail(priv)) 736 netif_start_queue(ndev); 737 } 738 739 arc_reg_set(priv, R_STATUS, TXPL_MASK); 740 741 return NETDEV_TX_OK; 742 } 743 744 static void arc_emac_set_address_internal(struct net_device *ndev) 745 { 746 struct arc_emac_priv *priv = netdev_priv(ndev); 747 unsigned int addr_low, addr_hi; 748 749 addr_low = le32_to_cpu(*(__le32 *)&ndev->dev_addr[0]); 750 addr_hi = le16_to_cpu(*(__le16 *)&ndev->dev_addr[4]); 751 752 arc_reg_set(priv, R_ADDRL, addr_low); 753 arc_reg_set(priv, R_ADDRH, addr_hi); 754 } 755 756 /** 757 * arc_emac_set_address - Set the MAC address for this device. 758 * @ndev: Pointer to net_device structure. 759 * @p: 6 byte Address to be written as MAC address. 760 * 761 * This function copies the HW address from the sockaddr structure to the 762 * net_device structure and updates the address in HW. 763 * 764 * returns: -EBUSY if the net device is busy or 0 if the address is set 765 * successfully. 766 */ 767 static int arc_emac_set_address(struct net_device *ndev, void *p) 768 { 769 struct sockaddr *addr = p; 770 771 if (netif_running(ndev)) 772 return -EBUSY; 773 774 if (!is_valid_ether_addr(addr->sa_data)) 775 return -EADDRNOTAVAIL; 776 777 memcpy(ndev->dev_addr, addr->sa_data, ndev->addr_len); 778 779 arc_emac_set_address_internal(ndev); 780 781 return 0; 782 } 783 784 /** 785 * arc_emac_restart - Restart EMAC 786 * @ndev: Pointer to net_device structure. 787 * 788 * This function do hardware reset of EMAC in order to restore 789 * network packets reception. 790 */ 791 static void arc_emac_restart(struct net_device *ndev) 792 { 793 struct arc_emac_priv *priv = netdev_priv(ndev); 794 struct net_device_stats *stats = &ndev->stats; 795 int i; 796 797 if (net_ratelimit()) 798 netdev_warn(ndev, "restarting stalled EMAC\n"); 799 800 netif_stop_queue(ndev); 801 802 /* Disable interrupts */ 803 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 804 805 /* Disable EMAC */ 806 arc_reg_clr(priv, R_CTRL, EN_MASK); 807 808 /* Return the sk_buff to system */ 809 arc_free_tx_queue(ndev); 810 811 /* Clean Tx BD's */ 812 priv->txbd_curr = 0; 813 priv->txbd_dirty = 0; 814 memset(priv->txbd, 0, TX_RING_SZ); 815 816 for (i = 0; i < RX_BD_NUM; i++) { 817 struct arc_emac_bd *rxbd = &priv->rxbd[i]; 818 unsigned int info = le32_to_cpu(rxbd->info); 819 820 if (!(info & FOR_EMAC)) { 821 stats->rx_errors++; 822 stats->rx_dropped++; 823 } 824 /* Return ownership to EMAC */ 825 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); 826 } 827 priv->last_rx_bd = 0; 828 829 /* Make sure info is visible to EMAC before enable */ 830 wmb(); 831 832 /* Enable interrupts */ 833 arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); 834 835 /* Enable EMAC */ 836 arc_reg_or(priv, R_CTRL, EN_MASK); 837 838 netif_start_queue(ndev); 839 } 840 841 static const struct net_device_ops arc_emac_netdev_ops = { 842 .ndo_open = arc_emac_open, 843 .ndo_stop = arc_emac_stop, 844 .ndo_start_xmit = arc_emac_tx, 845 .ndo_set_mac_address = arc_emac_set_address, 846 .ndo_get_stats = arc_emac_stats, 847 .ndo_set_rx_mode = arc_emac_set_rx_mode, 848 .ndo_do_ioctl = phy_do_ioctl_running, 849 #ifdef CONFIG_NET_POLL_CONTROLLER 850 .ndo_poll_controller = arc_emac_poll_controller, 851 #endif 852 }; 853 854 int arc_emac_probe(struct net_device *ndev, int interface) 855 { 856 struct device *dev = ndev->dev.parent; 857 struct resource res_regs; 858 struct device_node *phy_node; 859 struct phy_device *phydev = NULL; 860 struct arc_emac_priv *priv; 861 const char *mac_addr; 862 unsigned int id, clock_frequency, irq; 863 int err; 864 865 /* Get PHY from device tree */ 866 phy_node = of_parse_phandle(dev->of_node, "phy", 0); 867 if (!phy_node) { 868 dev_err(dev, "failed to retrieve phy description from device tree\n"); 869 return -ENODEV; 870 } 871 872 /* Get EMAC registers base address from device tree */ 873 err = of_address_to_resource(dev->of_node, 0, &res_regs); 874 if (err) { 875 dev_err(dev, "failed to retrieve registers base from device tree\n"); 876 err = -ENODEV; 877 goto out_put_node; 878 } 879 880 /* Get IRQ from device tree */ 881 irq = irq_of_parse_and_map(dev->of_node, 0); 882 if (!irq) { 883 dev_err(dev, "failed to retrieve <irq> value from device tree\n"); 884 err = -ENODEV; 885 goto out_put_node; 886 } 887 888 ndev->netdev_ops = &arc_emac_netdev_ops; 889 ndev->ethtool_ops = &arc_emac_ethtool_ops; 890 ndev->watchdog_timeo = TX_TIMEOUT; 891 892 priv = netdev_priv(ndev); 893 priv->dev = dev; 894 895 priv->regs = devm_ioremap_resource(dev, &res_regs); 896 if (IS_ERR(priv->regs)) { 897 err = PTR_ERR(priv->regs); 898 goto out_put_node; 899 } 900 901 dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs); 902 903 if (priv->clk) { 904 err = clk_prepare_enable(priv->clk); 905 if (err) { 906 dev_err(dev, "failed to enable clock\n"); 907 goto out_put_node; 908 } 909 910 clock_frequency = clk_get_rate(priv->clk); 911 } else { 912 /* Get CPU clock frequency from device tree */ 913 if (of_property_read_u32(dev->of_node, "clock-frequency", 914 &clock_frequency)) { 915 dev_err(dev, "failed to retrieve <clock-frequency> from device tree\n"); 916 err = -EINVAL; 917 goto out_put_node; 918 } 919 } 920 921 id = arc_reg_get(priv, R_ID); 922 923 /* Check for EMAC revision 5 or 7, magic number */ 924 if (!(id == 0x0005fd02 || id == 0x0007fd02)) { 925 dev_err(dev, "ARC EMAC not detected, id=0x%x\n", id); 926 err = -ENODEV; 927 goto out_clken; 928 } 929 dev_info(dev, "ARC EMAC detected with id: 0x%x\n", id); 930 931 /* Set poll rate so that it polls every 1 ms */ 932 arc_reg_set(priv, R_POLLRATE, clock_frequency / 1000000); 933 934 ndev->irq = irq; 935 dev_info(dev, "IRQ is %d\n", ndev->irq); 936 937 /* Register interrupt handler for device */ 938 err = devm_request_irq(dev, ndev->irq, arc_emac_intr, 0, 939 ndev->name, ndev); 940 if (err) { 941 dev_err(dev, "could not allocate IRQ\n"); 942 goto out_clken; 943 } 944 945 /* Get MAC address from device tree */ 946 mac_addr = of_get_mac_address(dev->of_node); 947 948 if (!IS_ERR(mac_addr)) 949 ether_addr_copy(ndev->dev_addr, mac_addr); 950 else 951 eth_hw_addr_random(ndev); 952 953 arc_emac_set_address_internal(ndev); 954 dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr); 955 956 /* Do 1 allocation instead of 2 separate ones for Rx and Tx BD rings */ 957 priv->rxbd = dmam_alloc_coherent(dev, RX_RING_SZ + TX_RING_SZ, 958 &priv->rxbd_dma, GFP_KERNEL); 959 960 if (!priv->rxbd) { 961 dev_err(dev, "failed to allocate data buffers\n"); 962 err = -ENOMEM; 963 goto out_clken; 964 } 965 966 priv->txbd = priv->rxbd + RX_BD_NUM; 967 968 priv->txbd_dma = priv->rxbd_dma + RX_RING_SZ; 969 dev_dbg(dev, "EMAC Device addr: Rx Ring [0x%x], Tx Ring[%x]\n", 970 (unsigned int)priv->rxbd_dma, (unsigned int)priv->txbd_dma); 971 972 err = arc_mdio_probe(priv); 973 if (err) { 974 dev_err(dev, "failed to probe MII bus\n"); 975 goto out_clken; 976 } 977 978 phydev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0, 979 interface); 980 if (!phydev) { 981 dev_err(dev, "of_phy_connect() failed\n"); 982 err = -ENODEV; 983 goto out_mdio; 984 } 985 986 dev_info(dev, "connected to %s phy with id 0x%x\n", 987 phydev->drv->name, phydev->phy_id); 988 989 netif_napi_add(ndev, &priv->napi, arc_emac_poll, ARC_EMAC_NAPI_WEIGHT); 990 991 err = register_netdev(ndev); 992 if (err) { 993 dev_err(dev, "failed to register network device\n"); 994 goto out_netif_api; 995 } 996 997 of_node_put(phy_node); 998 return 0; 999 1000 out_netif_api: 1001 netif_napi_del(&priv->napi); 1002 phy_disconnect(phydev); 1003 out_mdio: 1004 arc_mdio_remove(priv); 1005 out_clken: 1006 if (priv->clk) 1007 clk_disable_unprepare(priv->clk); 1008 out_put_node: 1009 of_node_put(phy_node); 1010 1011 return err; 1012 } 1013 EXPORT_SYMBOL_GPL(arc_emac_probe); 1014 1015 int arc_emac_remove(struct net_device *ndev) 1016 { 1017 struct arc_emac_priv *priv = netdev_priv(ndev); 1018 1019 phy_disconnect(ndev->phydev); 1020 arc_mdio_remove(priv); 1021 unregister_netdev(ndev); 1022 netif_napi_del(&priv->napi); 1023 1024 if (!IS_ERR(priv->clk)) 1025 clk_disable_unprepare(priv->clk); 1026 1027 return 0; 1028 } 1029 EXPORT_SYMBOL_GPL(arc_emac_remove); 1030 1031 MODULE_AUTHOR("Alexey Brodkin <abrodkin@synopsys.com>"); 1032 MODULE_DESCRIPTION("ARC EMAC driver"); 1033 MODULE_LICENSE("GPL"); 1034