Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 667 insertions, 0 deletions

diff --git a/drivers/net/ethernet/ezchip/nps_enet.c b/drivers/net/ethernet/ezchip/nps_enet.c
new file mode 100644
index 000000000..f1eb660aa
--- /dev/null
+++ b/drivers/net/ethernet/ezchip/nps_enet.c
@@ -0,0 +1,667 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright(c) 2015 EZchip Technologies.
+ */
+
+#include <linux/module.h>
+#include <linux/etherdevice.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_net.h>
+#include <linux/of_platform.h>
+#include "nps_enet.h"
+
+#define DRV_NAME			"nps_mgt_enet"
+
+static inline bool nps_enet_is_tx_pending(struct nps_enet_priv *priv)
+{
+	u32 tx_ctrl_value = nps_enet_reg_get(priv, NPS_ENET_REG_TX_CTL);
+	u32 tx_ctrl_ct = (tx_ctrl_value & TX_CTL_CT_MASK) >> TX_CTL_CT_SHIFT;
+
+	return (!tx_ctrl_ct && priv->tx_skb);
+}
+
+static void nps_enet_clean_rx_fifo(struct net_device *ndev, u32 frame_len)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 i, len = DIV_ROUND_UP(frame_len, sizeof(u32));
+
+	/* Empty Rx FIFO buffer by reading all words */
+	for (i = 0; i < len; i++)
+		nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
+}
+
+static void nps_enet_read_rx_fifo(struct net_device *ndev,
+				  unsigned char *dst, u32 length)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	s32 i, last = length & (sizeof(u32) - 1);
+	u32 *reg = (u32 *)dst, len = length / sizeof(u32);
+	bool dst_is_aligned = IS_ALIGNED((unsigned long)dst, sizeof(u32));
+
+	/* In case dst is not aligned we need an intermediate buffer */
+	if (dst_is_aligned) {
+		ioread32_rep(priv->regs_base + NPS_ENET_REG_RX_BUF, reg, len);
+		reg += len;
+	} else { /* !dst_is_aligned */
+		for (i = 0; i < len; i++, reg++) {
+			u32 buf = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
+
+			put_unaligned_be32(buf, reg);
+		}
+	}
+	/* copy last bytes (if any) */
+	if (last) {
+		u32 buf;
+
+		ioread32_rep(priv->regs_base + NPS_ENET_REG_RX_BUF, &buf, 1);
+		memcpy((u8 *)reg, &buf, last);
+	}
+}
+
+static u32 nps_enet_rx_handler(struct net_device *ndev)
+{
+	u32 frame_len, err = 0;
+	u32 work_done = 0;
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	struct sk_buff *skb;
+	u32 rx_ctrl_value = nps_enet_reg_get(priv, NPS_ENET_REG_RX_CTL);
+	u32 rx_ctrl_cr = (rx_ctrl_value & RX_CTL_CR_MASK) >> RX_CTL_CR_SHIFT;
+	u32 rx_ctrl_er = (rx_ctrl_value & RX_CTL_ER_MASK) >> RX_CTL_ER_SHIFT;
+	u32 rx_ctrl_crc = (rx_ctrl_value & RX_CTL_CRC_MASK) >> RX_CTL_CRC_SHIFT;
+
+	frame_len = (rx_ctrl_value & RX_CTL_NR_MASK) >> RX_CTL_NR_SHIFT;
+
+	/* Check if we got RX */
+	if (!rx_ctrl_cr)
+		return work_done;
+
+	/* If we got here there is a work for us */
+	work_done++;
+
+	/* Check Rx error */
+	if (rx_ctrl_er) {
+		ndev->stats.rx_errors++;
+		err = 1;
+	}
+
+	/* Check Rx CRC error */
+	if (rx_ctrl_crc) {
+		ndev->stats.rx_crc_errors++;
+		ndev->stats.rx_dropped++;
+		err = 1;
+	}
+
+	/* Check Frame length Min 64b */
+	if (unlikely(frame_len < ETH_ZLEN)) {
+		ndev->stats.rx_length_errors++;
+		ndev->stats.rx_dropped++;
+		err = 1;
+	}
+
+	if (err)
+		goto rx_irq_clean;
+
+	/* Skb allocation */
+	skb = netdev_alloc_skb_ip_align(ndev, frame_len);
+	if (unlikely(!skb)) {
+		ndev->stats.rx_errors++;
+		ndev->stats.rx_dropped++;
+		goto rx_irq_clean;
+	}
+
+	/* Copy frame from Rx fifo into the skb */
+	nps_enet_read_rx_fifo(ndev, skb->data, frame_len);
+
+	skb_put(skb, frame_len);
+	skb->protocol = eth_type_trans(skb, ndev);
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+	ndev->stats.rx_packets++;
+	ndev->stats.rx_bytes += frame_len;
+	netif_receive_skb(skb);
+
+	goto rx_irq_frame_done;
+
+rx_irq_clean:
+	/* Clean Rx fifo */
+	nps_enet_clean_rx_fifo(ndev, frame_len);
+
+rx_irq_frame_done:
+	/* Ack Rx ctrl register */
+	nps_enet_reg_set(priv, NPS_ENET_REG_RX_CTL, 0);
+
+	return work_done;
+}
+
+static void nps_enet_tx_handler(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 tx_ctrl_value = nps_enet_reg_get(priv, NPS_ENET_REG_TX_CTL);
+	u32 tx_ctrl_et = (tx_ctrl_value & TX_CTL_ET_MASK) >> TX_CTL_ET_SHIFT;
+	u32 tx_ctrl_nt = (tx_ctrl_value & TX_CTL_NT_MASK) >> TX_CTL_NT_SHIFT;
+
+	/* Check if we got TX */
+	if (!nps_enet_is_tx_pending(priv))
+		return;
+
+	/* Ack Tx ctrl register */
+	nps_enet_reg_set(priv, NPS_ENET_REG_TX_CTL, 0);
+
+	/* Check Tx transmit error */
+	if (unlikely(tx_ctrl_et)) {
+		ndev->stats.tx_errors++;
+	} else {
+		ndev->stats.tx_packets++;
+		ndev->stats.tx_bytes += tx_ctrl_nt;
+	}
+
+	dev_kfree_skb(priv->tx_skb);
+	priv->tx_skb = NULL;
+
+	if (netif_queue_stopped(ndev))
+		netif_wake_queue(ndev);
+}
+
+/**
+ * nps_enet_poll - NAPI poll handler.
+ * @napi:       Pointer to napi_struct structure.
+ * @budget:     How many frames to process on one call.
+ *
+ * returns:     Number of processed frames
+ */
+static int nps_enet_poll(struct napi_struct *napi, int budget)
+{
+	struct net_device *ndev = napi->dev;
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 work_done;
+
+	nps_enet_tx_handler(ndev);
+	work_done = nps_enet_rx_handler(ndev);
+	if ((work_done < budget) && napi_complete_done(napi, work_done)) {
+		u32 buf_int_enable_value = 0;
+
+		/* set tx_done and rx_rdy bits */
+		buf_int_enable_value |= NPS_ENET_ENABLE << RX_RDY_SHIFT;
+		buf_int_enable_value |= NPS_ENET_ENABLE << TX_DONE_SHIFT;
+
+		nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE,
+				 buf_int_enable_value);
+
+		/* in case we will get a tx interrupt while interrupts
+		 * are masked, we will lose it since the tx is edge interrupt.
+		 * specifically, while executing the code section above,
+		 * between nps_enet_tx_handler and the interrupts enable, all
+		 * tx requests will be stuck until we will get an rx interrupt.
+		 * the two code lines below will solve this situation by
+		 * re-adding ourselves to the poll list.
+		 */
+		if (nps_enet_is_tx_pending(priv)) {
+			nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, 0);
+			napi_reschedule(napi);
+		}
+	}
+
+	return work_done;
+}
+
+/**
+ * nps_enet_irq_handler - Global interrupt handler for ENET.
+ * @irq:                irq number.
+ * @dev_instance:       device instance.
+ *
+ * returns: IRQ_HANDLED for all cases.
+ *
+ * EZchip ENET has 2 interrupt causes, and depending on bits raised in
+ * CTRL registers we may tell what is a reason for interrupt to fire up.
+ * We got one for RX and the other for TX (completion).
+ */
+static irqreturn_t nps_enet_irq_handler(s32 irq, void *dev_instance)
+{
+	struct net_device *ndev = dev_instance;
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 rx_ctrl_value = nps_enet_reg_get(priv, NPS_ENET_REG_RX_CTL);
+	u32 rx_ctrl_cr = (rx_ctrl_value & RX_CTL_CR_MASK) >> RX_CTL_CR_SHIFT;
+
+	if (nps_enet_is_tx_pending(priv) || rx_ctrl_cr)
+		if (likely(napi_schedule_prep(&priv->napi))) {
+			nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, 0);
+			__napi_schedule(&priv->napi);
+		}
+
+	return IRQ_HANDLED;
+}
+
+static void nps_enet_set_hw_mac_address(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 ge_mac_cfg_1_value = 0;
+	u32 *ge_mac_cfg_2_value = &priv->ge_mac_cfg_2_value;
+
+	/* set MAC address in HW */
+	ge_mac_cfg_1_value |= ndev->dev_addr[0] << CFG_1_OCTET_0_SHIFT;
+	ge_mac_cfg_1_value |= ndev->dev_addr[1] << CFG_1_OCTET_1_SHIFT;
+	ge_mac_cfg_1_value |= ndev->dev_addr[2] << CFG_1_OCTET_2_SHIFT;
+	ge_mac_cfg_1_value |= ndev->dev_addr[3] << CFG_1_OCTET_3_SHIFT;
+	*ge_mac_cfg_2_value = (*ge_mac_cfg_2_value & ~CFG_2_OCTET_4_MASK)
+		 | ndev->dev_addr[4] << CFG_2_OCTET_4_SHIFT;
+	*ge_mac_cfg_2_value = (*ge_mac_cfg_2_value & ~CFG_2_OCTET_5_MASK)
+		 | ndev->dev_addr[5] << CFG_2_OCTET_5_SHIFT;
+
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_1,
+			 ge_mac_cfg_1_value);
+
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2,
+			 *ge_mac_cfg_2_value);
+}
+
+/**
+ * nps_enet_hw_reset - Reset the network device.
+ * @ndev:       Pointer to the network device.
+ *
+ * This function reset the PCS and TX fifo.
+ * The programming model is to set the relevant reset bits
+ * wait for some time for this to propagate and then unset
+ * the reset bits. This way we ensure that reset procedure
+ * is done successfully by device.
+ */
+static void nps_enet_hw_reset(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 ge_rst_value = 0, phase_fifo_ctl_value = 0;
+
+	/* Pcs reset sequence*/
+	ge_rst_value |= NPS_ENET_ENABLE << RST_GMAC_0_SHIFT;
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_RST, ge_rst_value);
+	usleep_range(10, 20);
+	ge_rst_value = 0;
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_RST, ge_rst_value);
+
+	/* Tx fifo reset sequence */
+	phase_fifo_ctl_value |= NPS_ENET_ENABLE << PHASE_FIFO_CTL_RST_SHIFT;
+	phase_fifo_ctl_value |= NPS_ENET_ENABLE << PHASE_FIFO_CTL_INIT_SHIFT;
+	nps_enet_reg_set(priv, NPS_ENET_REG_PHASE_FIFO_CTL,
+			 phase_fifo_ctl_value);
+	usleep_range(10, 20);
+	phase_fifo_ctl_value = 0;
+	nps_enet_reg_set(priv, NPS_ENET_REG_PHASE_FIFO_CTL,
+			 phase_fifo_ctl_value);
+}
+
+static void nps_enet_hw_enable_control(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 ge_mac_cfg_0_value = 0, buf_int_enable_value = 0;
+	u32 *ge_mac_cfg_2_value = &priv->ge_mac_cfg_2_value;
+	u32 *ge_mac_cfg_3_value = &priv->ge_mac_cfg_3_value;
+	s32 max_frame_length;
+
+	/* Enable Rx and Tx statistics */
+	*ge_mac_cfg_2_value = (*ge_mac_cfg_2_value & ~CFG_2_STAT_EN_MASK)
+		 | NPS_ENET_GE_MAC_CFG_2_STAT_EN << CFG_2_STAT_EN_SHIFT;
+
+	/* Discard packets with different MAC address */
+	*ge_mac_cfg_2_value = (*ge_mac_cfg_2_value & ~CFG_2_DISK_DA_MASK)
+		 | NPS_ENET_ENABLE << CFG_2_DISK_DA_SHIFT;
+
+	/* Discard multicast packets */
+	*ge_mac_cfg_2_value = (*ge_mac_cfg_2_value & ~CFG_2_DISK_MC_MASK)
+		 | NPS_ENET_ENABLE << CFG_2_DISK_MC_SHIFT;
+
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2,
+			 *ge_mac_cfg_2_value);
+
+	/* Discard Packets bigger than max frame length */
+	max_frame_length = ETH_HLEN + ndev->mtu + ETH_FCS_LEN;
+	if (max_frame_length <= NPS_ENET_MAX_FRAME_LENGTH) {
+		*ge_mac_cfg_3_value =
+			 (*ge_mac_cfg_3_value & ~CFG_3_MAX_LEN_MASK)
+			 | max_frame_length << CFG_3_MAX_LEN_SHIFT;
+	}
+
+	/* Enable interrupts */
+	buf_int_enable_value |= NPS_ENET_ENABLE << RX_RDY_SHIFT;
+	buf_int_enable_value |= NPS_ENET_ENABLE << TX_DONE_SHIFT;
+	nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE,
+			 buf_int_enable_value);
+
+	/* Write device MAC address to HW */
+	nps_enet_set_hw_mac_address(ndev);
+
+	/* Rx and Tx HW features */
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_TX_PAD_EN_SHIFT;
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_TX_CRC_EN_SHIFT;
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_RX_CRC_STRIP_SHIFT;
+
+	/* IFG configuration */
+	ge_mac_cfg_0_value |=
+		 NPS_ENET_GE_MAC_CFG_0_RX_IFG << CFG_0_RX_IFG_SHIFT;
+	ge_mac_cfg_0_value |=
+		 NPS_ENET_GE_MAC_CFG_0_TX_IFG << CFG_0_TX_IFG_SHIFT;
+
+	/* preamble configuration */
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_RX_PR_CHECK_EN_SHIFT;
+	ge_mac_cfg_0_value |=
+		 NPS_ENET_GE_MAC_CFG_0_TX_PR_LEN << CFG_0_TX_PR_LEN_SHIFT;
+
+	/* enable flow control frames */
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_TX_FC_EN_SHIFT;
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_RX_FC_EN_SHIFT;
+	ge_mac_cfg_0_value |=
+		 NPS_ENET_GE_MAC_CFG_0_TX_FC_RETR << CFG_0_TX_FC_RETR_SHIFT;
+	*ge_mac_cfg_3_value = (*ge_mac_cfg_3_value & ~CFG_3_CF_DROP_MASK)
+		 | NPS_ENET_ENABLE << CFG_3_CF_DROP_SHIFT;
+
+	/* Enable Rx and Tx */
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_RX_EN_SHIFT;
+	ge_mac_cfg_0_value |= NPS_ENET_ENABLE << CFG_0_TX_EN_SHIFT;
+
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_3,
+			 *ge_mac_cfg_3_value);
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_0,
+			 ge_mac_cfg_0_value);
+}
+
+static void nps_enet_hw_disable_control(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+
+	/* Disable interrupts */
+	nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, 0);
+
+	/* Disable Rx and Tx */
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_0, 0);
+}
+
+static void nps_enet_send_frame(struct net_device *ndev,
+				struct sk_buff *skb)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 tx_ctrl_value = 0;
+	short length = skb->len;
+	u32 i, len = DIV_ROUND_UP(length, sizeof(u32));
+	u32 *src = (void *)skb->data;
+	bool src_is_aligned = IS_ALIGNED((unsigned long)src, sizeof(u32));
+
+	/* In case src is not aligned we need an intermediate buffer */
+	if (src_is_aligned)
+		iowrite32_rep(priv->regs_base + NPS_ENET_REG_TX_BUF, src, len);
+	else /* !src_is_aligned */
+		for (i = 0; i < len; i++, src++)
+			nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF,
+					 get_unaligned_be32(src));
+
+	/* Write the length of the Frame */
+	tx_ctrl_value |= length << TX_CTL_NT_SHIFT;
+
+	tx_ctrl_value |= NPS_ENET_ENABLE << TX_CTL_CT_SHIFT;
+	/* Send Frame */
+	nps_enet_reg_set(priv, NPS_ENET_REG_TX_CTL, tx_ctrl_value);
+}
+
+/**
+ * nps_enet_set_mac_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 s32 nps_enet_set_mac_address(struct net_device *ndev, void *p)
+{
+	struct sockaddr *addr = p;
+	s32 res;
+
+	if (netif_running(ndev))
+		return -EBUSY;
+
+	res = eth_mac_addr(ndev, p);
+	if (!res) {
+		eth_hw_addr_set(ndev, addr->sa_data);
+		nps_enet_set_hw_mac_address(ndev);
+	}
+
+	return res;
+}
+
+/**
+ * nps_enet_set_rx_mode - Change the receive filtering mode.
+ * @ndev:       Pointer to the network device.
+ *
+ * This function enables/disables promiscuous mode
+ */
+static void nps_enet_set_rx_mode(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	u32 ge_mac_cfg_2_value = priv->ge_mac_cfg_2_value;
+
+	if (ndev->flags & IFF_PROMISC) {
+		ge_mac_cfg_2_value = (ge_mac_cfg_2_value & ~CFG_2_DISK_DA_MASK)
+			 | NPS_ENET_DISABLE << CFG_2_DISK_DA_SHIFT;
+		ge_mac_cfg_2_value = (ge_mac_cfg_2_value & ~CFG_2_DISK_MC_MASK)
+			 | NPS_ENET_DISABLE << CFG_2_DISK_MC_SHIFT;
+
+	} else {
+		ge_mac_cfg_2_value = (ge_mac_cfg_2_value & ~CFG_2_DISK_DA_MASK)
+			 | NPS_ENET_ENABLE << CFG_2_DISK_DA_SHIFT;
+		ge_mac_cfg_2_value = (ge_mac_cfg_2_value & ~CFG_2_DISK_MC_MASK)
+			 | NPS_ENET_ENABLE << CFG_2_DISK_MC_SHIFT;
+	}
+
+	nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2, ge_mac_cfg_2_value);
+}
+
+/**
+ * nps_enet_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 ENET device and starts the Tx queue.
+ */
+static s32 nps_enet_open(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+	s32 err;
+
+	/* Reset private variables */
+	priv->tx_skb = NULL;
+	priv->ge_mac_cfg_2_value = 0;
+	priv->ge_mac_cfg_3_value = 0;
+
+	/* ge_mac_cfg_3 default values */
+	priv->ge_mac_cfg_3_value |=
+		 NPS_ENET_GE_MAC_CFG_3_RX_IFG_TH << CFG_3_RX_IFG_TH_SHIFT;
+
+	priv->ge_mac_cfg_3_value |=
+		 NPS_ENET_GE_MAC_CFG_3_MAX_LEN << CFG_3_MAX_LEN_SHIFT;
+
+	/* Disable HW device */
+	nps_enet_hw_disable_control(ndev);
+
+	/* irq Rx allocation */
+	err = request_irq(priv->irq, nps_enet_irq_handler,
+			  0, "enet-rx-tx", ndev);
+	if (err)
+		return err;
+
+	napi_enable(&priv->napi);
+
+	/* Enable HW device */
+	nps_enet_hw_reset(ndev);
+	nps_enet_hw_enable_control(ndev);
+
+	netif_start_queue(ndev);
+
+	return 0;
+}
+
+/**
+ * nps_enet_stop - Close the network device.
+ * @ndev:       Pointer to the network device.
+ *
+ * This function stops the Tx queue, disables interrupts for the ENET device.
+ */
+static s32 nps_enet_stop(struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+
+	napi_disable(&priv->napi);
+	netif_stop_queue(ndev);
+	nps_enet_hw_disable_control(ndev);
+	free_irq(priv->irq, ndev);
+
+	return 0;
+}
+
+/**
+ * nps_enet_start_xmit - 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 nps_enet_start_xmit(struct sk_buff *skb,
+				       struct net_device *ndev)
+{
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+
+	/* This driver handles one frame at a time  */
+	netif_stop_queue(ndev);
+
+	priv->tx_skb = skb;
+
+	/* make sure tx_skb is actually written to the memory
+	 * before the HW is informed and the IRQ is fired.
+	 */
+	wmb();
+
+	nps_enet_send_frame(ndev, skb);
+
+	return NETDEV_TX_OK;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void nps_enet_poll_controller(struct net_device *ndev)
+{
+	disable_irq(ndev->irq);
+	nps_enet_irq_handler(ndev->irq, ndev);
+	enable_irq(ndev->irq);
+}
+#endif
+
+static const struct net_device_ops nps_netdev_ops = {
+	.ndo_open		= nps_enet_open,
+	.ndo_stop		= nps_enet_stop,
+	.ndo_start_xmit		= nps_enet_start_xmit,
+	.ndo_set_mac_address	= nps_enet_set_mac_address,
+	.ndo_set_rx_mode        = nps_enet_set_rx_mode,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller	= nps_enet_poll_controller,
+#endif
+};
+
+static s32 nps_enet_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct net_device *ndev;
+	struct nps_enet_priv *priv;
+	s32 err = 0;
+
+	if (!dev->of_node)
+		return -ENODEV;
+
+	ndev = alloc_etherdev(sizeof(struct nps_enet_priv));
+	if (!ndev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, ndev);
+	SET_NETDEV_DEV(ndev, dev);
+	priv = netdev_priv(ndev);
+
+	/* The EZ NET specific entries in the device structure. */
+	ndev->netdev_ops = &nps_netdev_ops;
+	ndev->watchdog_timeo = (400 * HZ / 1000);
+	/* FIXME :: no multicast support yet */
+	ndev->flags &= ~IFF_MULTICAST;
+
+	priv->regs_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->regs_base)) {
+		err = PTR_ERR(priv->regs_base);
+		goto out_netdev;
+	}
+	dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs_base);
+
+	/* set kernel MAC address to dev */
+	err = of_get_ethdev_address(dev->of_node, ndev);
+	if (err)
+		eth_hw_addr_random(ndev);
+
+	/* Get IRQ number */
+	priv->irq = platform_get_irq(pdev, 0);
+	if (priv->irq < 0) {
+		err = -ENODEV;
+		goto out_netdev;
+	}
+
+	netif_napi_add_weight(ndev, &priv->napi, nps_enet_poll,
+			      NPS_ENET_NAPI_POLL_WEIGHT);
+
+	/* Register the driver. Should be the last thing in probe */
+	err = register_netdev(ndev);
+	if (err) {
+		dev_err(dev, "Failed to register ndev for %s, err = 0x%08x\n",
+			ndev->name, (s32)err);
+		goto out_netif_api;
+	}
+
+	dev_info(dev, "(rx/tx=%d)\n", priv->irq);
+	return 0;
+
+out_netif_api:
+	netif_napi_del(&priv->napi);
+out_netdev:
+	free_netdev(ndev);
+
+	return err;
+}
+
+static s32 nps_enet_remove(struct platform_device *pdev)
+{
+	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct nps_enet_priv *priv = netdev_priv(ndev);
+
+	unregister_netdev(ndev);
+	netif_napi_del(&priv->napi);
+	free_netdev(ndev);
+
+	return 0;
+}
+
+static const struct of_device_id nps_enet_dt_ids[] = {
+	{ .compatible = "ezchip,nps-mgt-enet" },
+	{ /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, nps_enet_dt_ids);
+
+static struct platform_driver nps_enet_driver = {
+	.probe = nps_enet_probe,
+	.remove = nps_enet_remove,
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table  = nps_enet_dt_ids,
+	},
+};
+
+module_platform_driver(nps_enet_driver);
+
+MODULE_AUTHOR("EZchip Semiconductor");
+MODULE_LICENSE("GPL v2");