blob: c642c3d3e600606f281ec4819533702276c335fe [file] [log] [blame] [edit]
// 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;
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(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");