diff options
Diffstat (limited to 'drivers/net/ethernet/arc/emac_main.c')
| -rw-r--r-- | drivers/net/ethernet/arc/emac_main.c | 1029 |
1 files changed, 1029 insertions, 0 deletions
diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c new file mode 100644 index 000000000..ba0646b3b --- /dev/null +++ b/drivers/net/ethernet/arc/emac_main.c @@ -0,0 +1,1029 @@ +// 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); + + strscpy(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; + + eth_hw_addr_set(ndev, addr->sa_data); + + 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_eth_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_ethdev_address(dev->of_node, ndev); + 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_weight(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"); |