| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2004-2013 Synopsys, Inc. (www.synopsys.com) |
| * |
| * Driver for the ARC EMAC 10100 (hardware revision 5) |
| * |
| * Contributors: |
| * Amit Bhor |
| * Sameer Dhavale |
| * Vineet Gupta |
| */ |
| |
| #include <linux/crc32.h> |
| #include <linux/etherdevice.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/module.h> |
| #include <linux/of_address.h> |
| #include <linux/of_irq.h> |
| #include <linux/of_mdio.h> |
| #include <linux/of_net.h> |
| #include <linux/of_platform.h> |
| |
| #include "emac.h" |
| |
| static void arc_emac_restart(struct net_device *ndev); |
| |
| /** |
| * arc_emac_tx_avail - Return the number of available slots in the tx ring. |
| * @priv: Pointer to ARC EMAC private data structure. |
| * |
| * returns: the number of slots available for transmission in tx the ring. |
| */ |
| static inline int arc_emac_tx_avail(struct arc_emac_priv *priv) |
| { |
| return (priv->txbd_dirty + TX_BD_NUM - priv->txbd_curr - 1) % TX_BD_NUM; |
| } |
| |
| /** |
| * arc_emac_adjust_link - Adjust the PHY link duplex. |
| * @ndev: Pointer to the net_device structure. |
| * |
| * This function is called to change the duplex setting after auto negotiation |
| * is done by the PHY. |
| */ |
| static void arc_emac_adjust_link(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct phy_device *phy_dev = ndev->phydev; |
| unsigned int reg, state_changed = 0; |
| |
| if (priv->link != phy_dev->link) { |
| priv->link = phy_dev->link; |
| state_changed = 1; |
| } |
| |
| if (priv->speed != phy_dev->speed) { |
| priv->speed = phy_dev->speed; |
| state_changed = 1; |
| if (priv->set_mac_speed) |
| priv->set_mac_speed(priv, priv->speed); |
| } |
| |
| if (priv->duplex != phy_dev->duplex) { |
| reg = arc_reg_get(priv, R_CTRL); |
| |
| if (phy_dev->duplex == DUPLEX_FULL) |
| reg |= ENFL_MASK; |
| else |
| reg &= ~ENFL_MASK; |
| |
| arc_reg_set(priv, R_CTRL, reg); |
| priv->duplex = phy_dev->duplex; |
| state_changed = 1; |
| } |
| |
| if (state_changed) |
| phy_print_status(phy_dev); |
| } |
| |
| /** |
| * arc_emac_get_drvinfo - Get EMAC driver information. |
| * @ndev: Pointer to net_device structure. |
| * @info: Pointer to ethtool_drvinfo structure. |
| * |
| * This implements ethtool command for getting the driver information. |
| * Issue "ethtool -i ethX" under linux prompt to execute this function. |
| */ |
| static void arc_emac_get_drvinfo(struct net_device *ndev, |
| struct ethtool_drvinfo *info) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| |
| strlcpy(info->driver, priv->drv_name, sizeof(info->driver)); |
| } |
| |
| static const struct ethtool_ops arc_emac_ethtool_ops = { |
| .get_drvinfo = arc_emac_get_drvinfo, |
| .get_link = ethtool_op_get_link, |
| .get_link_ksettings = phy_ethtool_get_link_ksettings, |
| .set_link_ksettings = phy_ethtool_set_link_ksettings, |
| }; |
| |
| #define FIRST_OR_LAST_MASK (FIRST_MASK | LAST_MASK) |
| |
| /** |
| * arc_emac_tx_clean - clears processed by EMAC Tx BDs. |
| * @ndev: Pointer to the network device. |
| */ |
| static void arc_emac_tx_clean(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct net_device_stats *stats = &ndev->stats; |
| unsigned int i; |
| |
| for (i = 0; i < TX_BD_NUM; i++) { |
| unsigned int *txbd_dirty = &priv->txbd_dirty; |
| struct arc_emac_bd *txbd = &priv->txbd[*txbd_dirty]; |
| struct buffer_state *tx_buff = &priv->tx_buff[*txbd_dirty]; |
| struct sk_buff *skb = tx_buff->skb; |
| unsigned int info = le32_to_cpu(txbd->info); |
| |
| if ((info & FOR_EMAC) || !txbd->data || !skb) |
| break; |
| |
| if (unlikely(info & (DROP | DEFR | LTCL | UFLO))) { |
| stats->tx_errors++; |
| stats->tx_dropped++; |
| |
| if (info & DEFR) |
| stats->tx_carrier_errors++; |
| |
| if (info & LTCL) |
| stats->collisions++; |
| |
| if (info & UFLO) |
| stats->tx_fifo_errors++; |
| } else if (likely(info & FIRST_OR_LAST_MASK)) { |
| stats->tx_packets++; |
| stats->tx_bytes += skb->len; |
| } |
| |
| dma_unmap_single(&ndev->dev, dma_unmap_addr(tx_buff, addr), |
| dma_unmap_len(tx_buff, len), DMA_TO_DEVICE); |
| |
| /* return the sk_buff to system */ |
| dev_consume_skb_irq(skb); |
| |
| txbd->data = 0; |
| txbd->info = 0; |
| tx_buff->skb = NULL; |
| |
| *txbd_dirty = (*txbd_dirty + 1) % TX_BD_NUM; |
| } |
| |
| /* Ensure that txbd_dirty is visible to tx() before checking |
| * for queue stopped. |
| */ |
| smp_mb(); |
| |
| if (netif_queue_stopped(ndev) && arc_emac_tx_avail(priv)) |
| netif_wake_queue(ndev); |
| } |
| |
| /** |
| * arc_emac_rx - processing of Rx packets. |
| * @ndev: Pointer to the network device. |
| * @budget: How many BDs to process on 1 call. |
| * |
| * returns: Number of processed BDs |
| * |
| * Iterate through Rx BDs and deliver received packages to upper layer. |
| */ |
| static int arc_emac_rx(struct net_device *ndev, int budget) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| unsigned int work_done; |
| |
| for (work_done = 0; work_done < budget; work_done++) { |
| unsigned int *last_rx_bd = &priv->last_rx_bd; |
| struct net_device_stats *stats = &ndev->stats; |
| struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd]; |
| struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd]; |
| unsigned int pktlen, info = le32_to_cpu(rxbd->info); |
| struct sk_buff *skb; |
| dma_addr_t addr; |
| |
| if (unlikely((info & OWN_MASK) == FOR_EMAC)) |
| break; |
| |
| /* Make a note that we saw a packet at this BD. |
| * So next time, driver starts from this + 1 |
| */ |
| *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM; |
| |
| if (unlikely((info & FIRST_OR_LAST_MASK) != |
| FIRST_OR_LAST_MASK)) { |
| /* We pre-allocate buffers of MTU size so incoming |
| * packets won't be split/chained. |
| */ |
| if (net_ratelimit()) |
| netdev_err(ndev, "incomplete packet received\n"); |
| |
| /* Return ownership to EMAC */ |
| rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); |
| stats->rx_errors++; |
| stats->rx_length_errors++; |
| continue; |
| } |
| |
| /* Prepare the BD for next cycle. netif_receive_skb() |
| * only if new skb was allocated and mapped to avoid holes |
| * in the RX fifo. |
| */ |
| skb = netdev_alloc_skb_ip_align(ndev, EMAC_BUFFER_SIZE); |
| if (unlikely(!skb)) { |
| if (net_ratelimit()) |
| netdev_err(ndev, "cannot allocate skb\n"); |
| /* Return ownership to EMAC */ |
| rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); |
| stats->rx_errors++; |
| stats->rx_dropped++; |
| continue; |
| } |
| |
| addr = dma_map_single(&ndev->dev, (void *)skb->data, |
| EMAC_BUFFER_SIZE, DMA_FROM_DEVICE); |
| if (dma_mapping_error(&ndev->dev, addr)) { |
| if (net_ratelimit()) |
| netdev_err(ndev, "cannot map dma buffer\n"); |
| dev_kfree_skb(skb); |
| /* Return ownership to EMAC */ |
| rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); |
| stats->rx_errors++; |
| stats->rx_dropped++; |
| continue; |
| } |
| |
| /* unmap previosly mapped skb */ |
| dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr), |
| dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE); |
| |
| pktlen = info & LEN_MASK; |
| stats->rx_packets++; |
| stats->rx_bytes += pktlen; |
| skb_put(rx_buff->skb, pktlen); |
| rx_buff->skb->dev = ndev; |
| rx_buff->skb->protocol = eth_type_trans(rx_buff->skb, ndev); |
| |
| netif_receive_skb(rx_buff->skb); |
| |
| rx_buff->skb = skb; |
| dma_unmap_addr_set(rx_buff, addr, addr); |
| dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE); |
| |
| rxbd->data = cpu_to_le32(addr); |
| |
| /* Make sure pointer to data buffer is set */ |
| wmb(); |
| |
| /* Return ownership to EMAC */ |
| rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); |
| } |
| |
| return work_done; |
| } |
| |
| /** |
| * arc_emac_rx_miss_handle - handle R_MISS register |
| * @ndev: Pointer to the net_device structure. |
| */ |
| static void arc_emac_rx_miss_handle(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct net_device_stats *stats = &ndev->stats; |
| unsigned int miss; |
| |
| miss = arc_reg_get(priv, R_MISS); |
| if (miss) { |
| stats->rx_errors += miss; |
| stats->rx_missed_errors += miss; |
| priv->rx_missed_errors += miss; |
| } |
| } |
| |
| /** |
| * arc_emac_rx_stall_check - check RX stall |
| * @ndev: Pointer to the net_device structure. |
| * @budget: How many BDs requested to process on 1 call. |
| * @work_done: How many BDs processed |
| * |
| * Under certain conditions EMAC stop reception of incoming packets and |
| * continuously increment R_MISS register instead of saving data into |
| * provided buffer. This function detect that condition and restart |
| * EMAC. |
| */ |
| static void arc_emac_rx_stall_check(struct net_device *ndev, |
| int budget, unsigned int work_done) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct arc_emac_bd *rxbd; |
| |
| if (work_done) |
| priv->rx_missed_errors = 0; |
| |
| if (priv->rx_missed_errors && budget) { |
| rxbd = &priv->rxbd[priv->last_rx_bd]; |
| if (le32_to_cpu(rxbd->info) & FOR_EMAC) { |
| arc_emac_restart(ndev); |
| priv->rx_missed_errors = 0; |
| } |
| } |
| } |
| |
| /** |
| * arc_emac_poll - NAPI poll handler. |
| * @napi: Pointer to napi_struct structure. |
| * @budget: How many BDs to process on 1 call. |
| * |
| * returns: Number of processed BDs |
| */ |
| static int arc_emac_poll(struct napi_struct *napi, int budget) |
| { |
| struct net_device *ndev = napi->dev; |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| unsigned int work_done; |
| |
| arc_emac_tx_clean(ndev); |
| arc_emac_rx_miss_handle(ndev); |
| |
| work_done = arc_emac_rx(ndev, budget); |
| if (work_done < budget) { |
| napi_complete_done(napi, work_done); |
| arc_reg_or(priv, R_ENABLE, RXINT_MASK | TXINT_MASK); |
| } |
| |
| arc_emac_rx_stall_check(ndev, budget, work_done); |
| |
| return work_done; |
| } |
| |
| /** |
| * arc_emac_intr - Global interrupt handler for EMAC. |
| * @irq: irq number. |
| * @dev_instance: device instance. |
| * |
| * returns: IRQ_HANDLED for all cases. |
| * |
| * ARC EMAC has only 1 interrupt line, and depending on bits raised in |
| * STATUS register we may tell what is a reason for interrupt to fire. |
| */ |
| static irqreturn_t arc_emac_intr(int irq, void *dev_instance) |
| { |
| struct net_device *ndev = dev_instance; |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct net_device_stats *stats = &ndev->stats; |
| unsigned int status; |
| |
| status = arc_reg_get(priv, R_STATUS); |
| status &= ~MDIO_MASK; |
| |
| /* Reset all flags except "MDIO complete" */ |
| arc_reg_set(priv, R_STATUS, status); |
| |
| if (status & (RXINT_MASK | TXINT_MASK)) { |
| if (likely(napi_schedule_prep(&priv->napi))) { |
| arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK); |
| __napi_schedule(&priv->napi); |
| } |
| } |
| |
| if (status & ERR_MASK) { |
| /* MSER/RXCR/RXFR/RXFL interrupt fires on corresponding |
| * 8-bit error counter overrun. |
| */ |
| |
| if (status & MSER_MASK) { |
| stats->rx_missed_errors += 0x100; |
| stats->rx_errors += 0x100; |
| priv->rx_missed_errors += 0x100; |
| napi_schedule(&priv->napi); |
| } |
| |
| if (status & RXCR_MASK) { |
| stats->rx_crc_errors += 0x100; |
| stats->rx_errors += 0x100; |
| } |
| |
| if (status & RXFR_MASK) { |
| stats->rx_frame_errors += 0x100; |
| stats->rx_errors += 0x100; |
| } |
| |
| if (status & RXFL_MASK) { |
| stats->rx_over_errors += 0x100; |
| stats->rx_errors += 0x100; |
| } |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| #ifdef CONFIG_NET_POLL_CONTROLLER |
| static void arc_emac_poll_controller(struct net_device *dev) |
| { |
| disable_irq(dev->irq); |
| arc_emac_intr(dev->irq, dev); |
| enable_irq(dev->irq); |
| } |
| #endif |
| |
| /** |
| * arc_emac_open - Open the network device. |
| * @ndev: Pointer to the network device. |
| * |
| * returns: 0, on success or non-zero error value on failure. |
| * |
| * This function sets the MAC address, requests and enables an IRQ |
| * for the EMAC device and starts the Tx queue. |
| * It also connects to the phy device. |
| */ |
| static int arc_emac_open(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct phy_device *phy_dev = ndev->phydev; |
| int i; |
| |
| phy_dev->autoneg = AUTONEG_ENABLE; |
| phy_dev->speed = 0; |
| phy_dev->duplex = 0; |
| linkmode_and(phy_dev->advertising, phy_dev->advertising, |
| phy_dev->supported); |
| |
| priv->last_rx_bd = 0; |
| |
| /* Allocate and set buffers for Rx BD's */ |
| for (i = 0; i < RX_BD_NUM; i++) { |
| dma_addr_t addr; |
| unsigned int *last_rx_bd = &priv->last_rx_bd; |
| struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd]; |
| struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd]; |
| |
| rx_buff->skb = netdev_alloc_skb_ip_align(ndev, |
| EMAC_BUFFER_SIZE); |
| if (unlikely(!rx_buff->skb)) |
| return -ENOMEM; |
| |
| addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data, |
| EMAC_BUFFER_SIZE, DMA_FROM_DEVICE); |
| if (dma_mapping_error(&ndev->dev, addr)) { |
| netdev_err(ndev, "cannot dma map\n"); |
| dev_kfree_skb(rx_buff->skb); |
| return -ENOMEM; |
| } |
| dma_unmap_addr_set(rx_buff, addr, addr); |
| dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE); |
| |
| rxbd->data = cpu_to_le32(addr); |
| |
| /* Make sure pointer to data buffer is set */ |
| wmb(); |
| |
| /* Return ownership to EMAC */ |
| rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); |
| |
| *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM; |
| } |
| |
| priv->txbd_curr = 0; |
| priv->txbd_dirty = 0; |
| |
| /* Clean Tx BD's */ |
| memset(priv->txbd, 0, TX_RING_SZ); |
| |
| /* Initialize logical address filter */ |
| arc_reg_set(priv, R_LAFL, 0); |
| arc_reg_set(priv, R_LAFH, 0); |
| |
| /* Set BD ring pointers for device side */ |
| arc_reg_set(priv, R_RX_RING, (unsigned int)priv->rxbd_dma); |
| arc_reg_set(priv, R_TX_RING, (unsigned int)priv->txbd_dma); |
| |
| /* Enable interrupts */ |
| arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); |
| |
| /* Set CONTROL */ |
| arc_reg_set(priv, R_CTRL, |
| (RX_BD_NUM << 24) | /* RX BD table length */ |
| (TX_BD_NUM << 16) | /* TX BD table length */ |
| TXRN_MASK | RXRN_MASK); |
| |
| napi_enable(&priv->napi); |
| |
| /* Enable EMAC */ |
| arc_reg_or(priv, R_CTRL, EN_MASK); |
| |
| phy_start(ndev->phydev); |
| |
| netif_start_queue(ndev); |
| |
| return 0; |
| } |
| |
| /** |
| * arc_emac_set_rx_mode - Change the receive filtering mode. |
| * @ndev: Pointer to the network device. |
| * |
| * This function enables/disables promiscuous or all-multicast mode |
| * and updates the multicast filtering list of the network device. |
| */ |
| static void arc_emac_set_rx_mode(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| |
| if (ndev->flags & IFF_PROMISC) { |
| arc_reg_or(priv, R_CTRL, PROM_MASK); |
| } else { |
| arc_reg_clr(priv, R_CTRL, PROM_MASK); |
| |
| if (ndev->flags & IFF_ALLMULTI) { |
| arc_reg_set(priv, R_LAFL, ~0); |
| arc_reg_set(priv, R_LAFH, ~0); |
| } else if (ndev->flags & IFF_MULTICAST) { |
| struct netdev_hw_addr *ha; |
| unsigned int filter[2] = { 0, 0 }; |
| int bit; |
| |
| netdev_for_each_mc_addr(ha, ndev) { |
| bit = ether_crc_le(ETH_ALEN, ha->addr) >> 26; |
| filter[bit >> 5] |= 1 << (bit & 31); |
| } |
| |
| arc_reg_set(priv, R_LAFL, filter[0]); |
| arc_reg_set(priv, R_LAFH, filter[1]); |
| } else { |
| arc_reg_set(priv, R_LAFL, 0); |
| arc_reg_set(priv, R_LAFH, 0); |
| } |
| } |
| } |
| |
| /** |
| * arc_free_tx_queue - free skb from tx queue |
| * @ndev: Pointer to the network device. |
| * |
| * This function must be called while EMAC disable |
| */ |
| static void arc_free_tx_queue(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| unsigned int i; |
| |
| for (i = 0; i < TX_BD_NUM; i++) { |
| struct arc_emac_bd *txbd = &priv->txbd[i]; |
| struct buffer_state *tx_buff = &priv->tx_buff[i]; |
| |
| if (tx_buff->skb) { |
| dma_unmap_single(&ndev->dev, |
| dma_unmap_addr(tx_buff, addr), |
| dma_unmap_len(tx_buff, len), |
| DMA_TO_DEVICE); |
| |
| /* return the sk_buff to system */ |
| dev_kfree_skb_irq(tx_buff->skb); |
| } |
| |
| txbd->info = 0; |
| txbd->data = 0; |
| tx_buff->skb = NULL; |
| } |
| } |
| |
| /** |
| * arc_free_rx_queue - free skb from rx queue |
| * @ndev: Pointer to the network device. |
| * |
| * This function must be called while EMAC disable |
| */ |
| static void arc_free_rx_queue(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| unsigned int i; |
| |
| for (i = 0; i < RX_BD_NUM; i++) { |
| struct arc_emac_bd *rxbd = &priv->rxbd[i]; |
| struct buffer_state *rx_buff = &priv->rx_buff[i]; |
| |
| if (rx_buff->skb) { |
| dma_unmap_single(&ndev->dev, |
| dma_unmap_addr(rx_buff, addr), |
| dma_unmap_len(rx_buff, len), |
| DMA_FROM_DEVICE); |
| |
| /* return the sk_buff to system */ |
| dev_kfree_skb_irq(rx_buff->skb); |
| } |
| |
| rxbd->info = 0; |
| rxbd->data = 0; |
| rx_buff->skb = NULL; |
| } |
| } |
| |
| /** |
| * arc_emac_stop - Close the network device. |
| * @ndev: Pointer to the network device. |
| * |
| * This function stops the Tx queue, disables interrupts and frees the IRQ for |
| * the EMAC device. |
| * It also disconnects the PHY device associated with the EMAC device. |
| */ |
| static int arc_emac_stop(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| |
| napi_disable(&priv->napi); |
| netif_stop_queue(ndev); |
| |
| phy_stop(ndev->phydev); |
| |
| /* Disable interrupts */ |
| arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); |
| |
| /* Disable EMAC */ |
| arc_reg_clr(priv, R_CTRL, EN_MASK); |
| |
| /* Return the sk_buff to system */ |
| arc_free_tx_queue(ndev); |
| arc_free_rx_queue(ndev); |
| |
| return 0; |
| } |
| |
| /** |
| * arc_emac_stats - Get system network statistics. |
| * @ndev: Pointer to net_device structure. |
| * |
| * Returns the address of the device statistics structure. |
| * Statistics are updated in interrupt handler. |
| */ |
| static struct net_device_stats *arc_emac_stats(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct net_device_stats *stats = &ndev->stats; |
| unsigned long miss, rxerr; |
| u8 rxcrc, rxfram, rxoflow; |
| |
| rxerr = arc_reg_get(priv, R_RXERR); |
| miss = arc_reg_get(priv, R_MISS); |
| |
| rxcrc = rxerr; |
| rxfram = rxerr >> 8; |
| rxoflow = rxerr >> 16; |
| |
| stats->rx_errors += miss; |
| stats->rx_errors += rxcrc + rxfram + rxoflow; |
| |
| stats->rx_over_errors += rxoflow; |
| stats->rx_frame_errors += rxfram; |
| stats->rx_crc_errors += rxcrc; |
| stats->rx_missed_errors += miss; |
| |
| return stats; |
| } |
| |
| /** |
| * arc_emac_tx - Starts the data transmission. |
| * @skb: sk_buff pointer that contains data to be Transmitted. |
| * @ndev: Pointer to net_device structure. |
| * |
| * returns: NETDEV_TX_OK, on success |
| * NETDEV_TX_BUSY, if any of the descriptors are not free. |
| * |
| * This function is invoked from upper layers to initiate transmission. |
| */ |
| static netdev_tx_t arc_emac_tx(struct sk_buff *skb, struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| unsigned int len, *txbd_curr = &priv->txbd_curr; |
| struct net_device_stats *stats = &ndev->stats; |
| __le32 *info = &priv->txbd[*txbd_curr].info; |
| dma_addr_t addr; |
| |
| if (skb_padto(skb, ETH_ZLEN)) |
| return NETDEV_TX_OK; |
| |
| len = max_t(unsigned int, ETH_ZLEN, skb->len); |
| |
| if (unlikely(!arc_emac_tx_avail(priv))) { |
| netif_stop_queue(ndev); |
| netdev_err(ndev, "BUG! Tx Ring full when queue awake!\n"); |
| return NETDEV_TX_BUSY; |
| } |
| |
| addr = dma_map_single(&ndev->dev, (void *)skb->data, len, |
| DMA_TO_DEVICE); |
| |
| if (unlikely(dma_mapping_error(&ndev->dev, addr))) { |
| stats->tx_dropped++; |
| stats->tx_errors++; |
| dev_kfree_skb_any(skb); |
| return NETDEV_TX_OK; |
| } |
| dma_unmap_addr_set(&priv->tx_buff[*txbd_curr], addr, addr); |
| dma_unmap_len_set(&priv->tx_buff[*txbd_curr], len, len); |
| |
| priv->txbd[*txbd_curr].data = cpu_to_le32(addr); |
| |
| /* Make sure pointer to data buffer is set */ |
| wmb(); |
| |
| skb_tx_timestamp(skb); |
| |
| *info = cpu_to_le32(FOR_EMAC | FIRST_OR_LAST_MASK | len); |
| |
| /* Make sure info word is set */ |
| wmb(); |
| |
| priv->tx_buff[*txbd_curr].skb = skb; |
| |
| /* Increment index to point to the next BD */ |
| *txbd_curr = (*txbd_curr + 1) % TX_BD_NUM; |
| |
| /* Ensure that tx_clean() sees the new txbd_curr before |
| * checking the queue status. This prevents an unneeded wake |
| * of the queue in tx_clean(). |
| */ |
| smp_mb(); |
| |
| if (!arc_emac_tx_avail(priv)) { |
| netif_stop_queue(ndev); |
| /* Refresh tx_dirty */ |
| smp_mb(); |
| if (arc_emac_tx_avail(priv)) |
| netif_start_queue(ndev); |
| } |
| |
| arc_reg_set(priv, R_STATUS, TXPL_MASK); |
| |
| return NETDEV_TX_OK; |
| } |
| |
| static void arc_emac_set_address_internal(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| unsigned int addr_low, addr_hi; |
| |
| addr_low = le32_to_cpu(*(__le32 *)&ndev->dev_addr[0]); |
| addr_hi = le16_to_cpu(*(__le16 *)&ndev->dev_addr[4]); |
| |
| arc_reg_set(priv, R_ADDRL, addr_low); |
| arc_reg_set(priv, R_ADDRH, addr_hi); |
| } |
| |
| /** |
| * arc_emac_set_address - Set the MAC address for this device. |
| * @ndev: Pointer to net_device structure. |
| * @p: 6 byte Address to be written as MAC address. |
| * |
| * This function copies the HW address from the sockaddr structure to the |
| * net_device structure and updates the address in HW. |
| * |
| * returns: -EBUSY if the net device is busy or 0 if the address is set |
| * successfully. |
| */ |
| static int arc_emac_set_address(struct net_device *ndev, void *p) |
| { |
| struct sockaddr *addr = p; |
| |
| if (netif_running(ndev)) |
| return -EBUSY; |
| |
| if (!is_valid_ether_addr(addr->sa_data)) |
| return -EADDRNOTAVAIL; |
| |
| memcpy(ndev->dev_addr, addr->sa_data, ndev->addr_len); |
| |
| arc_emac_set_address_internal(ndev); |
| |
| return 0; |
| } |
| |
| /** |
| * arc_emac_restart - Restart EMAC |
| * @ndev: Pointer to net_device structure. |
| * |
| * This function do hardware reset of EMAC in order to restore |
| * network packets reception. |
| */ |
| static void arc_emac_restart(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| struct net_device_stats *stats = &ndev->stats; |
| int i; |
| |
| if (net_ratelimit()) |
| netdev_warn(ndev, "restarting stalled EMAC\n"); |
| |
| netif_stop_queue(ndev); |
| |
| /* Disable interrupts */ |
| arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); |
| |
| /* Disable EMAC */ |
| arc_reg_clr(priv, R_CTRL, EN_MASK); |
| |
| /* Return the sk_buff to system */ |
| arc_free_tx_queue(ndev); |
| |
| /* Clean Tx BD's */ |
| priv->txbd_curr = 0; |
| priv->txbd_dirty = 0; |
| memset(priv->txbd, 0, TX_RING_SZ); |
| |
| for (i = 0; i < RX_BD_NUM; i++) { |
| struct arc_emac_bd *rxbd = &priv->rxbd[i]; |
| unsigned int info = le32_to_cpu(rxbd->info); |
| |
| if (!(info & FOR_EMAC)) { |
| stats->rx_errors++; |
| stats->rx_dropped++; |
| } |
| /* Return ownership to EMAC */ |
| rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE); |
| } |
| priv->last_rx_bd = 0; |
| |
| /* Make sure info is visible to EMAC before enable */ |
| wmb(); |
| |
| /* Enable interrupts */ |
| arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK); |
| |
| /* Enable EMAC */ |
| arc_reg_or(priv, R_CTRL, EN_MASK); |
| |
| netif_start_queue(ndev); |
| } |
| |
| static const struct net_device_ops arc_emac_netdev_ops = { |
| .ndo_open = arc_emac_open, |
| .ndo_stop = arc_emac_stop, |
| .ndo_start_xmit = arc_emac_tx, |
| .ndo_set_mac_address = arc_emac_set_address, |
| .ndo_get_stats = arc_emac_stats, |
| .ndo_set_rx_mode = arc_emac_set_rx_mode, |
| .ndo_do_ioctl = phy_do_ioctl_running, |
| #ifdef CONFIG_NET_POLL_CONTROLLER |
| .ndo_poll_controller = arc_emac_poll_controller, |
| #endif |
| }; |
| |
| int arc_emac_probe(struct net_device *ndev, int interface) |
| { |
| struct device *dev = ndev->dev.parent; |
| struct resource res_regs; |
| struct device_node *phy_node; |
| struct phy_device *phydev = NULL; |
| struct arc_emac_priv *priv; |
| unsigned int id, clock_frequency, irq; |
| int err; |
| |
| /* Get PHY from device tree */ |
| phy_node = of_parse_phandle(dev->of_node, "phy", 0); |
| if (!phy_node) { |
| dev_err(dev, "failed to retrieve phy description from device tree\n"); |
| return -ENODEV; |
| } |
| |
| /* Get EMAC registers base address from device tree */ |
| err = of_address_to_resource(dev->of_node, 0, &res_regs); |
| if (err) { |
| dev_err(dev, "failed to retrieve registers base from device tree\n"); |
| err = -ENODEV; |
| goto out_put_node; |
| } |
| |
| /* Get IRQ from device tree */ |
| irq = irq_of_parse_and_map(dev->of_node, 0); |
| if (!irq) { |
| dev_err(dev, "failed to retrieve <irq> value from device tree\n"); |
| err = -ENODEV; |
| goto out_put_node; |
| } |
| |
| ndev->netdev_ops = &arc_emac_netdev_ops; |
| ndev->ethtool_ops = &arc_emac_ethtool_ops; |
| ndev->watchdog_timeo = TX_TIMEOUT; |
| |
| priv = netdev_priv(ndev); |
| priv->dev = dev; |
| |
| priv->regs = devm_ioremap_resource(dev, &res_regs); |
| if (IS_ERR(priv->regs)) { |
| err = PTR_ERR(priv->regs); |
| goto out_put_node; |
| } |
| |
| dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs); |
| |
| if (priv->clk) { |
| err = clk_prepare_enable(priv->clk); |
| if (err) { |
| dev_err(dev, "failed to enable clock\n"); |
| goto out_put_node; |
| } |
| |
| clock_frequency = clk_get_rate(priv->clk); |
| } else { |
| /* Get CPU clock frequency from device tree */ |
| if (of_property_read_u32(dev->of_node, "clock-frequency", |
| &clock_frequency)) { |
| dev_err(dev, "failed to retrieve <clock-frequency> from device tree\n"); |
| err = -EINVAL; |
| goto out_put_node; |
| } |
| } |
| |
| id = arc_reg_get(priv, R_ID); |
| |
| /* Check for EMAC revision 5 or 7, magic number */ |
| if (!(id == 0x0005fd02 || id == 0x0007fd02)) { |
| dev_err(dev, "ARC EMAC not detected, id=0x%x\n", id); |
| err = -ENODEV; |
| goto out_clken; |
| } |
| dev_info(dev, "ARC EMAC detected with id: 0x%x\n", id); |
| |
| /* Set poll rate so that it polls every 1 ms */ |
| arc_reg_set(priv, R_POLLRATE, clock_frequency / 1000000); |
| |
| ndev->irq = irq; |
| dev_info(dev, "IRQ is %d\n", ndev->irq); |
| |
| /* Register interrupt handler for device */ |
| err = devm_request_irq(dev, ndev->irq, arc_emac_intr, 0, |
| ndev->name, ndev); |
| if (err) { |
| dev_err(dev, "could not allocate IRQ\n"); |
| goto out_clken; |
| } |
| |
| /* Get MAC address from device tree */ |
| err = of_get_mac_address(dev->of_node, ndev->dev_addr); |
| if (err) |
| eth_hw_addr_random(ndev); |
| |
| arc_emac_set_address_internal(ndev); |
| dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr); |
| |
| /* Do 1 allocation instead of 2 separate ones for Rx and Tx BD rings */ |
| priv->rxbd = dmam_alloc_coherent(dev, RX_RING_SZ + TX_RING_SZ, |
| &priv->rxbd_dma, GFP_KERNEL); |
| |
| if (!priv->rxbd) { |
| dev_err(dev, "failed to allocate data buffers\n"); |
| err = -ENOMEM; |
| goto out_clken; |
| } |
| |
| priv->txbd = priv->rxbd + RX_BD_NUM; |
| |
| priv->txbd_dma = priv->rxbd_dma + RX_RING_SZ; |
| dev_dbg(dev, "EMAC Device addr: Rx Ring [0x%x], Tx Ring[%x]\n", |
| (unsigned int)priv->rxbd_dma, (unsigned int)priv->txbd_dma); |
| |
| err = arc_mdio_probe(priv); |
| if (err) { |
| dev_err(dev, "failed to probe MII bus\n"); |
| goto out_clken; |
| } |
| |
| phydev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0, |
| interface); |
| if (!phydev) { |
| dev_err(dev, "of_phy_connect() failed\n"); |
| err = -ENODEV; |
| goto out_mdio; |
| } |
| |
| dev_info(dev, "connected to %s phy with id 0x%x\n", |
| phydev->drv->name, phydev->phy_id); |
| |
| netif_napi_add(ndev, &priv->napi, arc_emac_poll, ARC_EMAC_NAPI_WEIGHT); |
| |
| err = register_netdev(ndev); |
| if (err) { |
| dev_err(dev, "failed to register network device\n"); |
| goto out_netif_api; |
| } |
| |
| of_node_put(phy_node); |
| return 0; |
| |
| out_netif_api: |
| netif_napi_del(&priv->napi); |
| phy_disconnect(phydev); |
| out_mdio: |
| arc_mdio_remove(priv); |
| out_clken: |
| if (priv->clk) |
| clk_disable_unprepare(priv->clk); |
| out_put_node: |
| of_node_put(phy_node); |
| |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(arc_emac_probe); |
| |
| int arc_emac_remove(struct net_device *ndev) |
| { |
| struct arc_emac_priv *priv = netdev_priv(ndev); |
| |
| phy_disconnect(ndev->phydev); |
| arc_mdio_remove(priv); |
| unregister_netdev(ndev); |
| netif_napi_del(&priv->napi); |
| |
| if (!IS_ERR(priv->clk)) |
| clk_disable_unprepare(priv->clk); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(arc_emac_remove); |
| |
| MODULE_AUTHOR("Alexey Brodkin <abrodkin@synopsys.com>"); |
| MODULE_DESCRIPTION("ARC EMAC driver"); |
| MODULE_LICENSE("GPL"); |