2 * Copyright (C) 2004-2013 Synopsys, Inc. (www.synopsys.com)
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
8 * Driver for the ARC EMAC 10100 (hardware revision 5)
16 #include <linux/etherdevice.h>
17 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <linux/of_address.h>
21 #include <linux/of_irq.h>
22 #include <linux/of_mdio.h>
23 #include <linux/of_net.h>
24 #include <linux/of_platform.h>
28 #define DRV_NAME "arc_emac"
29 #define DRV_VERSION "1.0"
32 * arc_emac_adjust_link - Adjust the PHY link duplex.
33 * @ndev: Pointer to the net_device structure.
35 * This function is called to change the duplex setting after auto negotiation
38 static void arc_emac_adjust_link(struct net_device *ndev)
40 struct arc_emac_priv *priv = netdev_priv(ndev);
41 struct phy_device *phy_dev = priv->phy_dev;
42 unsigned int reg, state_changed = 0;
44 if (priv->link != phy_dev->link) {
45 priv->link = phy_dev->link;
49 if (priv->speed != phy_dev->speed) {
50 priv->speed = phy_dev->speed;
54 if (priv->duplex != phy_dev->duplex) {
55 reg = arc_reg_get(priv, R_CTRL);
57 if (DUPLEX_FULL == phy_dev->duplex)
62 arc_reg_set(priv, R_CTRL, reg);
63 priv->duplex = phy_dev->duplex;
68 phy_print_status(phy_dev);
72 * arc_emac_get_settings - Get PHY settings.
73 * @ndev: Pointer to net_device structure.
74 * @cmd: Pointer to ethtool_cmd structure.
76 * This implements ethtool command for getting PHY settings. If PHY could
77 * not be found, the function returns -ENODEV. This function calls the
78 * relevant PHY ethtool API to get the PHY settings.
79 * Issue "ethtool ethX" under linux prompt to execute this function.
81 static int arc_emac_get_settings(struct net_device *ndev,
82 struct ethtool_cmd *cmd)
84 struct arc_emac_priv *priv = netdev_priv(ndev);
86 return phy_ethtool_gset(priv->phy_dev, cmd);
90 * arc_emac_set_settings - Set PHY settings as passed in the argument.
91 * @ndev: Pointer to net_device structure.
92 * @cmd: Pointer to ethtool_cmd structure.
94 * This implements ethtool command for setting various PHY settings. If PHY
95 * could not be found, the function returns -ENODEV. This function calls the
96 * relevant PHY ethtool API to set the PHY.
97 * Issue e.g. "ethtool -s ethX speed 1000" under linux prompt to execute this
100 static int arc_emac_set_settings(struct net_device *ndev,
101 struct ethtool_cmd *cmd)
103 struct arc_emac_priv *priv = netdev_priv(ndev);
105 if (!capable(CAP_NET_ADMIN))
108 return phy_ethtool_sset(priv->phy_dev, cmd);
112 * arc_emac_get_drvinfo - Get EMAC driver information.
113 * @ndev: Pointer to net_device structure.
114 * @info: Pointer to ethtool_drvinfo structure.
116 * This implements ethtool command for getting the driver information.
117 * Issue "ethtool -i ethX" under linux prompt to execute this function.
119 static void arc_emac_get_drvinfo(struct net_device *ndev,
120 struct ethtool_drvinfo *info)
122 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
123 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
126 static const struct ethtool_ops arc_emac_ethtool_ops = {
127 .get_settings = arc_emac_get_settings,
128 .set_settings = arc_emac_set_settings,
129 .get_drvinfo = arc_emac_get_drvinfo,
130 .get_link = ethtool_op_get_link,
133 #define FIRST_OR_LAST_MASK (FIRST_MASK | LAST_MASK)
136 * arc_emac_tx_clean - clears processed by EMAC Tx BDs.
137 * @ndev: Pointer to the network device.
139 static void arc_emac_tx_clean(struct net_device *ndev)
141 struct arc_emac_priv *priv = netdev_priv(ndev);
142 struct net_device_stats *stats = &priv->stats;
145 for (i = 0; i < TX_BD_NUM; i++) {
146 unsigned int *txbd_dirty = &priv->txbd_dirty;
147 struct arc_emac_bd *txbd = &priv->txbd[*txbd_dirty];
148 struct buffer_state *tx_buff = &priv->tx_buff[*txbd_dirty];
149 struct sk_buff *skb = tx_buff->skb;
150 unsigned int info = le32_to_cpu(txbd->info);
152 if ((info & FOR_EMAC) || !txbd->data)
155 if (unlikely(info & (DROP | DEFR | LTCL | UFLO))) {
160 stats->tx_carrier_errors++;
166 stats->tx_fifo_errors++;
167 } else if (likely(info & FIRST_OR_LAST_MASK)) {
169 stats->tx_bytes += skb->len;
172 dma_unmap_single(&ndev->dev, dma_unmap_addr(tx_buff, addr),
173 dma_unmap_len(tx_buff, len), DMA_TO_DEVICE);
175 /* return the sk_buff to system */
176 dev_kfree_skb_irq(skb);
181 *txbd_dirty = (*txbd_dirty + 1) % TX_BD_NUM;
183 if (netif_queue_stopped(ndev))
184 netif_wake_queue(ndev);
189 * arc_emac_rx - processing of Rx packets.
190 * @ndev: Pointer to the network device.
191 * @budget: How many BDs to process on 1 call.
193 * returns: Number of processed BDs
195 * Iterate through Rx BDs and deliver received packages to upper layer.
197 static int arc_emac_rx(struct net_device *ndev, int budget)
199 struct arc_emac_priv *priv = netdev_priv(ndev);
200 unsigned int work_done;
202 for (work_done = 0; work_done < budget; work_done++) {
203 unsigned int *last_rx_bd = &priv->last_rx_bd;
204 struct net_device_stats *stats = &priv->stats;
205 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd];
206 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd];
207 unsigned int pktlen, info = le32_to_cpu(rxbd->info);
211 if (unlikely((info & OWN_MASK) == FOR_EMAC))
214 /* Make a note that we saw a packet at this BD.
215 * So next time, driver starts from this + 1
217 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM;
219 if (unlikely((info & FIRST_OR_LAST_MASK) !=
220 FIRST_OR_LAST_MASK)) {
221 /* We pre-allocate buffers of MTU size so incoming
222 * packets won't be split/chained.
225 netdev_err(ndev, "incomplete packet received\n");
227 /* Return ownership to EMAC */
228 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
230 stats->rx_length_errors++;
234 pktlen = info & LEN_MASK;
236 stats->rx_bytes += pktlen;
238 skb_put(skb, pktlen);
240 skb->protocol = eth_type_trans(skb, ndev);
242 dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr),
243 dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE);
245 /* Prepare the BD for next cycle */
246 rx_buff->skb = netdev_alloc_skb_ip_align(ndev,
248 if (unlikely(!rx_buff->skb)) {
250 /* Because receive_skb is below, increment rx_dropped */
255 /* receive_skb only if new skb was allocated to avoid holes */
256 netif_receive_skb(skb);
258 addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data,
259 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE);
260 if (dma_mapping_error(&ndev->dev, addr)) {
262 netdev_err(ndev, "cannot dma map\n");
263 dev_kfree_skb(rx_buff->skb);
267 dma_unmap_addr_set(rx_buff, addr, addr);
268 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE);
270 rxbd->data = cpu_to_le32(addr);
272 /* Make sure pointer to data buffer is set */
275 /* Return ownership to EMAC */
276 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
283 * arc_emac_poll - NAPI poll handler.
284 * @napi: Pointer to napi_struct structure.
285 * @budget: How many BDs to process on 1 call.
287 * returns: Number of processed BDs
289 static int arc_emac_poll(struct napi_struct *napi, int budget)
291 struct net_device *ndev = napi->dev;
292 struct arc_emac_priv *priv = netdev_priv(ndev);
293 unsigned int work_done;
295 arc_emac_tx_clean(ndev);
297 work_done = arc_emac_rx(ndev, budget);
298 if (work_done < budget) {
300 arc_reg_or(priv, R_ENABLE, RXINT_MASK);
307 * arc_emac_intr - Global interrupt handler for EMAC.
309 * @dev_instance: device instance.
311 * returns: IRQ_HANDLED for all cases.
313 * ARC EMAC has only 1 interrupt line, and depending on bits raised in
314 * STATUS register we may tell what is a reason for interrupt to fire.
316 static irqreturn_t arc_emac_intr(int irq, void *dev_instance)
318 struct net_device *ndev = dev_instance;
319 struct arc_emac_priv *priv = netdev_priv(ndev);
320 struct net_device_stats *stats = &priv->stats;
323 status = arc_reg_get(priv, R_STATUS);
324 status &= ~MDIO_MASK;
326 /* Reset all flags except "MDIO complete" */
327 arc_reg_set(priv, R_STATUS, status);
329 if (status & RXINT_MASK) {
330 if (likely(napi_schedule_prep(&priv->napi))) {
331 arc_reg_clr(priv, R_ENABLE, RXINT_MASK);
332 __napi_schedule(&priv->napi);
336 if (status & ERR_MASK) {
337 /* MSER/RXCR/RXFR/RXFL interrupt fires on corresponding
338 * 8-bit error counter overrun.
341 if (status & MSER_MASK) {
342 stats->rx_missed_errors += 0x100;
343 stats->rx_errors += 0x100;
346 if (status & RXCR_MASK) {
347 stats->rx_crc_errors += 0x100;
348 stats->rx_errors += 0x100;
351 if (status & RXFR_MASK) {
352 stats->rx_frame_errors += 0x100;
353 stats->rx_errors += 0x100;
356 if (status & RXFL_MASK) {
357 stats->rx_over_errors += 0x100;
358 stats->rx_errors += 0x100;
366 * arc_emac_open - Open the network device.
367 * @ndev: Pointer to the network device.
369 * returns: 0, on success or non-zero error value on failure.
371 * This function sets the MAC address, requests and enables an IRQ
372 * for the EMAC device and starts the Tx queue.
373 * It also connects to the phy device.
375 static int arc_emac_open(struct net_device *ndev)
377 struct arc_emac_priv *priv = netdev_priv(ndev);
378 struct phy_device *phy_dev = priv->phy_dev;
381 phy_dev->autoneg = AUTONEG_ENABLE;
384 phy_dev->advertising &= phy_dev->supported;
386 priv->last_rx_bd = 0;
388 /* Allocate and set buffers for Rx BD's */
389 for (i = 0; i < RX_BD_NUM; i++) {
391 unsigned int *last_rx_bd = &priv->last_rx_bd;
392 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd];
393 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd];
395 rx_buff->skb = netdev_alloc_skb_ip_align(ndev,
397 if (unlikely(!rx_buff->skb))
400 addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data,
401 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE);
402 if (dma_mapping_error(&ndev->dev, addr)) {
403 netdev_err(ndev, "cannot dma map\n");
404 dev_kfree_skb(rx_buff->skb);
407 dma_unmap_addr_set(rx_buff, addr, addr);
408 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE);
410 rxbd->data = cpu_to_le32(addr);
412 /* Make sure pointer to data buffer is set */
415 /* Return ownership to EMAC */
416 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
418 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM;
422 memset(priv->txbd, 0, TX_RING_SZ);
424 /* Initialize logical address filter */
425 arc_reg_set(priv, R_LAFL, 0);
426 arc_reg_set(priv, R_LAFH, 0);
428 /* Set BD ring pointers for device side */
429 arc_reg_set(priv, R_RX_RING, (unsigned int)priv->rxbd_dma);
430 arc_reg_set(priv, R_TX_RING, (unsigned int)priv->txbd_dma);
432 /* Enable interrupts */
433 arc_reg_set(priv, R_ENABLE, RXINT_MASK | ERR_MASK);
436 arc_reg_set(priv, R_CTRL,
437 (RX_BD_NUM << 24) | /* RX BD table length */
438 (TX_BD_NUM << 16) | /* TX BD table length */
439 TXRN_MASK | RXRN_MASK);
441 napi_enable(&priv->napi);
444 arc_reg_or(priv, R_CTRL, EN_MASK);
446 phy_start_aneg(priv->phy_dev);
448 netif_start_queue(ndev);
454 * arc_emac_stop - Close the network device.
455 * @ndev: Pointer to the network device.
457 * This function stops the Tx queue, disables interrupts and frees the IRQ for
459 * It also disconnects the PHY device associated with the EMAC device.
461 static int arc_emac_stop(struct net_device *ndev)
463 struct arc_emac_priv *priv = netdev_priv(ndev);
465 napi_disable(&priv->napi);
466 netif_stop_queue(ndev);
468 /* Disable interrupts */
469 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | ERR_MASK);
472 arc_reg_clr(priv, R_CTRL, EN_MASK);
478 * arc_emac_stats - Get system network statistics.
479 * @ndev: Pointer to net_device structure.
481 * Returns the address of the device statistics structure.
482 * Statistics are updated in interrupt handler.
484 static struct net_device_stats *arc_emac_stats(struct net_device *ndev)
486 struct arc_emac_priv *priv = netdev_priv(ndev);
487 struct net_device_stats *stats = &priv->stats;
488 unsigned long miss, rxerr;
489 u8 rxcrc, rxfram, rxoflow;
491 rxerr = arc_reg_get(priv, R_RXERR);
492 miss = arc_reg_get(priv, R_MISS);
496 rxoflow = rxerr >> 16;
498 stats->rx_errors += miss;
499 stats->rx_errors += rxcrc + rxfram + rxoflow;
501 stats->rx_over_errors += rxoflow;
502 stats->rx_frame_errors += rxfram;
503 stats->rx_crc_errors += rxcrc;
504 stats->rx_missed_errors += miss;
510 * arc_emac_tx - Starts the data transmission.
511 * @skb: sk_buff pointer that contains data to be Transmitted.
512 * @ndev: Pointer to net_device structure.
514 * returns: NETDEV_TX_OK, on success
515 * NETDEV_TX_BUSY, if any of the descriptors are not free.
517 * This function is invoked from upper layers to initiate transmission.
519 static int arc_emac_tx(struct sk_buff *skb, struct net_device *ndev)
521 struct arc_emac_priv *priv = netdev_priv(ndev);
522 unsigned int len, *txbd_curr = &priv->txbd_curr;
523 struct net_device_stats *stats = &priv->stats;
524 __le32 *info = &priv->txbd[*txbd_curr].info;
527 if (skb_padto(skb, ETH_ZLEN))
530 len = max_t(unsigned int, ETH_ZLEN, skb->len);
532 /* EMAC still holds this buffer in its possession.
533 * CPU must not modify this buffer descriptor
535 if (unlikely((le32_to_cpu(*info) & OWN_MASK) == FOR_EMAC)) {
536 netif_stop_queue(ndev);
537 return NETDEV_TX_BUSY;
540 addr = dma_map_single(&ndev->dev, (void *)skb->data, len,
543 if (unlikely(dma_mapping_error(&ndev->dev, addr))) {
549 dma_unmap_addr_set(&priv->tx_buff[*txbd_curr], addr, addr);
550 dma_unmap_len_set(&priv->tx_buff[*txbd_curr], len, len);
552 priv->tx_buff[*txbd_curr].skb = skb;
553 priv->txbd[*txbd_curr].data = cpu_to_le32(addr);
555 /* Make sure pointer to data buffer is set */
558 skb_tx_timestamp(skb);
560 *info = cpu_to_le32(FOR_EMAC | FIRST_OR_LAST_MASK | len);
562 /* Increment index to point to the next BD */
563 *txbd_curr = (*txbd_curr + 1) % TX_BD_NUM;
565 /* Get "info" of the next BD */
566 info = &priv->txbd[*txbd_curr].info;
568 /* Check if if Tx BD ring is full - next BD is still owned by EMAC */
569 if (unlikely((le32_to_cpu(*info) & OWN_MASK) == FOR_EMAC))
570 netif_stop_queue(ndev);
572 arc_reg_set(priv, R_STATUS, TXPL_MASK);
578 * arc_emac_set_address - Set the MAC address for this device.
579 * @ndev: Pointer to net_device structure.
580 * @p: 6 byte Address to be written as MAC address.
582 * This function copies the HW address from the sockaddr structure to the
583 * net_device structure and updates the address in HW.
585 * returns: -EBUSY if the net device is busy or 0 if the address is set
588 static int arc_emac_set_address(struct net_device *ndev, void *p)
590 struct arc_emac_priv *priv = netdev_priv(ndev);
591 struct sockaddr *addr = p;
592 unsigned int addr_low, addr_hi;
594 if (netif_running(ndev))
597 if (!is_valid_ether_addr(addr->sa_data))
598 return -EADDRNOTAVAIL;
600 memcpy(ndev->dev_addr, addr->sa_data, ndev->addr_len);
602 addr_low = le32_to_cpu(*(__le32 *) &ndev->dev_addr[0]);
603 addr_hi = le16_to_cpu(*(__le16 *) &ndev->dev_addr[4]);
605 arc_reg_set(priv, R_ADDRL, addr_low);
606 arc_reg_set(priv, R_ADDRH, addr_hi);
611 static const struct net_device_ops arc_emac_netdev_ops = {
612 .ndo_open = arc_emac_open,
613 .ndo_stop = arc_emac_stop,
614 .ndo_start_xmit = arc_emac_tx,
615 .ndo_set_mac_address = arc_emac_set_address,
616 .ndo_get_stats = arc_emac_stats,
619 static int arc_emac_probe(struct platform_device *pdev)
621 struct resource res_regs;
622 struct device_node *phy_node;
623 struct arc_emac_priv *priv;
624 struct net_device *ndev;
625 const char *mac_addr;
626 unsigned int id, clock_frequency, irq;
629 if (!pdev->dev.of_node)
632 /* Get PHY from device tree */
633 phy_node = of_parse_phandle(pdev->dev.of_node, "phy", 0);
635 dev_err(&pdev->dev, "failed to retrieve phy description from device tree\n");
639 /* Get EMAC registers base address from device tree */
640 err = of_address_to_resource(pdev->dev.of_node, 0, &res_regs);
642 dev_err(&pdev->dev, "failed to retrieve registers base from device tree\n");
646 /* Get CPU clock frequency from device tree */
647 if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
649 dev_err(&pdev->dev, "failed to retrieve <clock-frequency> from device tree\n");
653 /* Get IRQ from device tree */
654 irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
656 dev_err(&pdev->dev, "failed to retrieve <irq> value from device tree\n");
660 ndev = alloc_etherdev(sizeof(struct arc_emac_priv));
664 platform_set_drvdata(pdev, ndev);
665 SET_NETDEV_DEV(ndev, &pdev->dev);
667 ndev->netdev_ops = &arc_emac_netdev_ops;
668 ndev->ethtool_ops = &arc_emac_ethtool_ops;
669 ndev->watchdog_timeo = TX_TIMEOUT;
670 /* FIXME :: no multicast support yet */
671 ndev->flags &= ~IFF_MULTICAST;
673 priv = netdev_priv(ndev);
674 priv->dev = &pdev->dev;
677 priv->regs = devm_ioremap_resource(&pdev->dev, &res_regs);
678 if (IS_ERR(priv->regs)) {
679 err = PTR_ERR(priv->regs);
682 dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs);
684 id = arc_reg_get(priv, R_ID);
686 /* Check for EMAC revision 5 or 7, magic number */
687 if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
688 dev_err(&pdev->dev, "ARC EMAC not detected, id=0x%x\n", id);
692 dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id);
694 /* Set poll rate so that it polls every 1 ms */
695 arc_reg_set(priv, R_POLLRATE, clock_frequency / 1000000);
698 dev_info(&pdev->dev, "IRQ is %d\n", ndev->irq);
700 /* Register interrupt handler for device */
701 err = devm_request_irq(&pdev->dev, ndev->irq, arc_emac_intr, 0,
704 dev_err(&pdev->dev, "could not allocate IRQ\n");
708 /* Get MAC address from device tree */
709 mac_addr = of_get_mac_address(pdev->dev.of_node);
712 memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
714 eth_hw_addr_random(ndev);
716 dev_info(&pdev->dev, "MAC address is now %pM\n", ndev->dev_addr);
718 /* Do 1 allocation instead of 2 separate ones for Rx and Tx BD rings */
719 priv->rxbd = dmam_alloc_coherent(&pdev->dev, RX_RING_SZ + TX_RING_SZ,
720 &priv->rxbd_dma, GFP_KERNEL);
723 dev_err(&pdev->dev, "failed to allocate data buffers\n");
728 priv->txbd = priv->rxbd + RX_BD_NUM;
730 priv->txbd_dma = priv->rxbd_dma + RX_RING_SZ;
731 dev_dbg(&pdev->dev, "EMAC Device addr: Rx Ring [0x%x], Tx Ring[%x]\n",
732 (unsigned int)priv->rxbd_dma, (unsigned int)priv->txbd_dma);
734 err = arc_mdio_probe(pdev, priv);
736 dev_err(&pdev->dev, "failed to probe MII bus\n");
740 priv->phy_dev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
741 PHY_INTERFACE_MODE_MII);
742 if (!priv->phy_dev) {
743 dev_err(&pdev->dev, "of_phy_connect() failed\n");
748 dev_info(&pdev->dev, "connected to %s phy with id 0x%x\n",
749 priv->phy_dev->drv->name, priv->phy_dev->phy_id);
751 netif_napi_add(ndev, &priv->napi, arc_emac_poll, ARC_EMAC_NAPI_WEIGHT);
753 err = register_netdev(ndev);
755 netif_napi_del(&priv->napi);
756 dev_err(&pdev->dev, "failed to register network device\n");
767 static int arc_emac_remove(struct platform_device *pdev)
769 struct net_device *ndev = platform_get_drvdata(pdev);
770 struct arc_emac_priv *priv = netdev_priv(ndev);
772 phy_disconnect(priv->phy_dev);
773 priv->phy_dev = NULL;
774 arc_mdio_remove(priv);
775 unregister_netdev(ndev);
776 netif_napi_del(&priv->napi);
782 static const struct of_device_id arc_emac_dt_ids[] = {
783 { .compatible = "snps,arc-emac" },
786 MODULE_DEVICE_TABLE(of, arc_emac_dt_ids);
788 static struct platform_driver arc_emac_driver = {
789 .probe = arc_emac_probe,
790 .remove = arc_emac_remove,
793 .owner = THIS_MODULE,
794 .of_match_table = arc_emac_dt_ids,
798 module_platform_driver(arc_emac_driver);
800 MODULE_AUTHOR("Alexey Brodkin <abrodkin@synopsys.com>");
801 MODULE_DESCRIPTION("ARC EMAC driver");
802 MODULE_LICENSE("GPL");