/* Copyright (c) 2014 Linaro Ltd.
 * Copyright (c) 2014 Hisilicon Limited.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/etherdevice.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/ktime.h>
#include <linux/of_address.h>
#include <linux/phy.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>

#define PPE_CFG_RX_ADDR			0x100
#define PPE_CFG_POOL_GRP		0x300
#define PPE_CFG_RX_BUF_SIZE		0x400
#define PPE_CFG_RX_FIFO_SIZE		0x500
#define PPE_CURR_BUF_CNT		0xa200

#define GE_DUPLEX_TYPE			0x08
#define GE_MAX_FRM_SIZE_REG		0x3c
#define GE_PORT_MODE			0x40
#define GE_PORT_EN			0x44
#define GE_SHORT_RUNTS_THR_REG		0x50
#define GE_TX_LOCAL_PAGE_REG		0x5c
#define GE_TRANSMIT_CONTROL_REG		0x60
#define GE_CF_CRC_STRIP_REG		0x1b0
#define GE_MODE_CHANGE_REG		0x1b4
#define GE_RECV_CONTROL_REG		0x1e0
#define GE_STATION_MAC_ADDRESS		0x210
#define PPE_CFG_CPU_ADD_ADDR		0x580
#define PPE_CFG_MAX_FRAME_LEN_REG	0x408
#define PPE_CFG_BUS_CTRL_REG		0x424
#define PPE_CFG_RX_CTRL_REG		0x428
#define PPE_CFG_RX_PKT_MODE_REG		0x438
#define PPE_CFG_QOS_VMID_GEN		0x500
#define PPE_CFG_RX_PKT_INT		0x538
#define PPE_INTEN			0x600
#define PPE_INTSTS			0x608
#define PPE_RINT			0x604
#define PPE_CFG_STS_MODE		0x700
#define PPE_HIS_RX_PKT_CNT		0x804

/* REG_INTERRUPT */
#define RCV_INT				BIT(10)
#define RCV_NOBUF			BIT(8)
#define RCV_DROP			BIT(7)
#define TX_DROP				BIT(6)
#define DEF_INT_ERR			(RCV_NOBUF | RCV_DROP | TX_DROP)
#define DEF_INT_MASK			(RCV_INT | DEF_INT_ERR)

/* TX descriptor config */
#define TX_FREE_MEM			BIT(0)
#define TX_READ_ALLOC_L3		BIT(1)
#define TX_FINISH_CACHE_INV		BIT(2)
#define TX_CLEAR_WB			BIT(4)
#define TX_L3_CHECKSUM			BIT(5)
#define TX_LOOP_BACK			BIT(11)

/* RX error */
#define RX_PKT_DROP			BIT(0)
#define RX_L2_ERR			BIT(1)
#define RX_PKT_ERR			(RX_PKT_DROP | RX_L2_ERR)

#define SGMII_SPEED_1000		0x08
#define SGMII_SPEED_100			0x07
#define SGMII_SPEED_10			0x06
#define MII_SPEED_100			0x01
#define MII_SPEED_10			0x00

#define GE_DUPLEX_FULL			BIT(0)
#define GE_DUPLEX_HALF			0x00
#define GE_MODE_CHANGE_EN		BIT(0)

#define GE_TX_AUTO_NEG			BIT(5)
#define GE_TX_ADD_CRC			BIT(6)
#define GE_TX_SHORT_PAD_THROUGH		BIT(7)

#define GE_RX_STRIP_CRC			BIT(0)
#define GE_RX_STRIP_PAD			BIT(3)
#define GE_RX_PAD_EN			BIT(4)

#define GE_AUTO_NEG_CTL			BIT(0)

#define GE_RX_INT_THRESHOLD		BIT(6)
#define GE_RX_TIMEOUT			0x04

#define GE_RX_PORT_EN			BIT(1)
#define GE_TX_PORT_EN			BIT(2)

#define PPE_CFG_STS_RX_PKT_CNT_RC	BIT(12)

#define PPE_CFG_RX_PKT_ALIGN		BIT(18)
#define PPE_CFG_QOS_VMID_MODE		BIT(14)
#define PPE_CFG_QOS_VMID_GRP_SHIFT	8

#define PPE_CFG_RX_FIFO_FSFU		BIT(11)
#define PPE_CFG_RX_DEPTH_SHIFT		16
#define PPE_CFG_RX_START_SHIFT		0
#define PPE_CFG_RX_CTRL_ALIGN_SHIFT	11

#define PPE_CFG_BUS_LOCAL_REL		BIT(14)
#define PPE_CFG_BUS_BIG_ENDIEN		BIT(0)

#define RX_DESC_NUM			128
#define TX_DESC_NUM			256
#define TX_NEXT(N)			(((N) + 1) & (TX_DESC_NUM-1))
#define RX_NEXT(N)			(((N) + 1) & (RX_DESC_NUM-1))

#define GMAC_PPE_RX_PKT_MAX_LEN		379
#define GMAC_MAX_PKT_LEN		1516
#define GMAC_MIN_PKT_LEN		31
#define RX_BUF_SIZE			1600
#define RESET_TIMEOUT			1000
#define TX_TIMEOUT			(6 * HZ)

#define DRV_NAME			"hip04-ether"
#define DRV_VERSION			"v1.0"

#define HIP04_MAX_TX_COALESCE_USECS	200
#define HIP04_MIN_TX_COALESCE_USECS	100
#define HIP04_MAX_TX_COALESCE_FRAMES	200
#define HIP04_MIN_TX_COALESCE_FRAMES	100

struct tx_desc {
	u32 send_addr;
	u32 send_size;
	u32 next_addr;
	u32 cfg;
	u32 wb_addr;
} __aligned(64);

struct rx_desc {
	u16 reserved_16;
	u16 pkt_len;
	u32 reserve1[3];
	u32 pkt_err;
	u32 reserve2[4];
};

struct hip04_priv {
	void __iomem *base;
	int phy_mode;
	int chan;
	unsigned int port;
	unsigned int speed;
	unsigned int duplex;
	unsigned int reg_inten;

	struct napi_struct napi;
	struct net_device *ndev;

	struct tx_desc *tx_desc;
	dma_addr_t tx_desc_dma;
	struct sk_buff *tx_skb[TX_DESC_NUM];
	dma_addr_t tx_phys[TX_DESC_NUM];
	unsigned int tx_head;

	int tx_coalesce_frames;
	int tx_coalesce_usecs;
	struct hrtimer tx_coalesce_timer;

	unsigned char *rx_buf[RX_DESC_NUM];
	dma_addr_t rx_phys[RX_DESC_NUM];
	unsigned int rx_head;
	unsigned int rx_buf_size;

	struct device_node *phy_node;
	struct phy_device *phy;
	struct regmap *map;
	struct work_struct tx_timeout_task;

	/* written only by tx cleanup */
	unsigned int tx_tail ____cacheline_aligned_in_smp;
};

static inline unsigned int tx_count(unsigned int head, unsigned int tail)
{
	return (head - tail) % (TX_DESC_NUM - 1);
}

static void hip04_config_port(struct net_device *ndev, u32 speed, u32 duplex)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	u32 val;

	priv->speed = speed;
	priv->duplex = duplex;

	switch (priv->phy_mode) {
	case PHY_INTERFACE_MODE_SGMII:
		if (speed == SPEED_1000)
			val = SGMII_SPEED_1000;
		else if (speed == SPEED_100)
			val = SGMII_SPEED_100;
		else
			val = SGMII_SPEED_10;
		break;
	case PHY_INTERFACE_MODE_MII:
		if (speed == SPEED_100)
			val = MII_SPEED_100;
		else
			val = MII_SPEED_10;
		break;
	default:
		netdev_warn(ndev, "not supported mode\n");
		val = MII_SPEED_10;
		break;
	}
	writel_relaxed(val, priv->base + GE_PORT_MODE);

	val = duplex ? GE_DUPLEX_FULL : GE_DUPLEX_HALF;
	writel_relaxed(val, priv->base + GE_DUPLEX_TYPE);

	val = GE_MODE_CHANGE_EN;
	writel_relaxed(val, priv->base + GE_MODE_CHANGE_REG);
}

static void hip04_reset_ppe(struct hip04_priv *priv)
{
	u32 val, tmp, timeout = 0;

	do {
		regmap_read(priv->map, priv->port * 4 + PPE_CURR_BUF_CNT, &val);
		regmap_read(priv->map, priv->port * 4 + PPE_CFG_RX_ADDR, &tmp);
		if (timeout++ > RESET_TIMEOUT)
			break;
	} while (val & 0xfff);
}

static void hip04_config_fifo(struct hip04_priv *priv)
{
	u32 val;

	val = readl_relaxed(priv->base + PPE_CFG_STS_MODE);
	val |= PPE_CFG_STS_RX_PKT_CNT_RC;
	writel_relaxed(val, priv->base + PPE_CFG_STS_MODE);

	val = BIT(priv->port);
	regmap_write(priv->map, priv->port * 4 + PPE_CFG_POOL_GRP, val);

	val = priv->port << PPE_CFG_QOS_VMID_GRP_SHIFT;
	val |= PPE_CFG_QOS_VMID_MODE;
	writel_relaxed(val, priv->base + PPE_CFG_QOS_VMID_GEN);

	val = RX_BUF_SIZE;
	regmap_write(priv->map, priv->port * 4 + PPE_CFG_RX_BUF_SIZE, val);

	val = RX_DESC_NUM << PPE_CFG_RX_DEPTH_SHIFT;
	val |= PPE_CFG_RX_FIFO_FSFU;
	val |= priv->chan << PPE_CFG_RX_START_SHIFT;
	regmap_write(priv->map, priv->port * 4 + PPE_CFG_RX_FIFO_SIZE, val);

	val = NET_IP_ALIGN << PPE_CFG_RX_CTRL_ALIGN_SHIFT;
	writel_relaxed(val, priv->base + PPE_CFG_RX_CTRL_REG);

	val = PPE_CFG_RX_PKT_ALIGN;
	writel_relaxed(val, priv->base + PPE_CFG_RX_PKT_MODE_REG);

	val = PPE_CFG_BUS_LOCAL_REL | PPE_CFG_BUS_BIG_ENDIEN;
	writel_relaxed(val, priv->base + PPE_CFG_BUS_CTRL_REG);

	val = GMAC_PPE_RX_PKT_MAX_LEN;
	writel_relaxed(val, priv->base + PPE_CFG_MAX_FRAME_LEN_REG);

	val = GMAC_MAX_PKT_LEN;
	writel_relaxed(val, priv->base + GE_MAX_FRM_SIZE_REG);

	val = GMAC_MIN_PKT_LEN;
	writel_relaxed(val, priv->base + GE_SHORT_RUNTS_THR_REG);

	val = readl_relaxed(priv->base + GE_TRANSMIT_CONTROL_REG);
	val |= GE_TX_AUTO_NEG | GE_TX_ADD_CRC | GE_TX_SHORT_PAD_THROUGH;
	writel_relaxed(val, priv->base + GE_TRANSMIT_CONTROL_REG);

	val = GE_RX_STRIP_CRC;
	writel_relaxed(val, priv->base + GE_CF_CRC_STRIP_REG);

	val = readl_relaxed(priv->base + GE_RECV_CONTROL_REG);
	val |= GE_RX_STRIP_PAD | GE_RX_PAD_EN;
	writel_relaxed(val, priv->base + GE_RECV_CONTROL_REG);

	val = GE_AUTO_NEG_CTL;
	writel_relaxed(val, priv->base + GE_TX_LOCAL_PAGE_REG);
}

static void hip04_mac_enable(struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	u32 val;

	/* enable tx & rx */
	val = readl_relaxed(priv->base + GE_PORT_EN);
	val |= GE_RX_PORT_EN | GE_TX_PORT_EN;
	writel_relaxed(val, priv->base + GE_PORT_EN);

	/* clear rx int */
	val = RCV_INT;
	writel_relaxed(val, priv->base + PPE_RINT);

	/* config recv int */
	val = GE_RX_INT_THRESHOLD | GE_RX_TIMEOUT;
	writel_relaxed(val, priv->base + PPE_CFG_RX_PKT_INT);

	/* enable interrupt */
	priv->reg_inten = DEF_INT_MASK;
	writel_relaxed(priv->reg_inten, priv->base + PPE_INTEN);
}

static void hip04_mac_disable(struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	u32 val;

	/* disable int */
	priv->reg_inten &= ~(DEF_INT_MASK);
	writel_relaxed(priv->reg_inten, priv->base + PPE_INTEN);

	/* disable tx & rx */
	val = readl_relaxed(priv->base + GE_PORT_EN);
	val &= ~(GE_RX_PORT_EN | GE_TX_PORT_EN);
	writel_relaxed(val, priv->base + GE_PORT_EN);
}

static void hip04_set_xmit_desc(struct hip04_priv *priv, dma_addr_t phys)
{
	writel(phys, priv->base + PPE_CFG_CPU_ADD_ADDR);
}

static void hip04_set_recv_desc(struct hip04_priv *priv, dma_addr_t phys)
{
	regmap_write(priv->map, priv->port * 4 + PPE_CFG_RX_ADDR, phys);
}

static u32 hip04_recv_cnt(struct hip04_priv *priv)
{
	return readl(priv->base + PPE_HIS_RX_PKT_CNT);
}

static void hip04_update_mac_address(struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);

	writel_relaxed(((ndev->dev_addr[0] << 8) | (ndev->dev_addr[1])),
		       priv->base + GE_STATION_MAC_ADDRESS);
	writel_relaxed(((ndev->dev_addr[2] << 24) | (ndev->dev_addr[3] << 16) |
			(ndev->dev_addr[4] << 8) | (ndev->dev_addr[5])),
		       priv->base + GE_STATION_MAC_ADDRESS + 4);
}

static int hip04_set_mac_address(struct net_device *ndev, void *addr)
{
	eth_mac_addr(ndev, addr);
	hip04_update_mac_address(ndev);
	return 0;
}

static int hip04_tx_reclaim(struct net_device *ndev, bool force)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	unsigned tx_tail = priv->tx_tail;
	struct tx_desc *desc;
	unsigned int bytes_compl = 0, pkts_compl = 0;
	unsigned int count;

	smp_rmb();
	count = tx_count(ACCESS_ONCE(priv->tx_head), tx_tail);
	if (count == 0)
		goto out;

	while (count) {
		desc = &priv->tx_desc[tx_tail];
		if (desc->send_addr != 0) {
			if (force)
				desc->send_addr = 0;
			else
				break;
		}

		if (priv->tx_phys[tx_tail]) {
			dma_unmap_single(&ndev->dev, priv->tx_phys[tx_tail],
					 priv->tx_skb[tx_tail]->len,
					 DMA_TO_DEVICE);
			priv->tx_phys[tx_tail] = 0;
		}
		pkts_compl++;
		bytes_compl += priv->tx_skb[tx_tail]->len;
		dev_kfree_skb(priv->tx_skb[tx_tail]);
		priv->tx_skb[tx_tail] = NULL;
		tx_tail = TX_NEXT(tx_tail);
		count--;
	}

	priv->tx_tail = tx_tail;
	smp_wmb(); /* Ensure tx_tail visible to xmit */

out:
	if (pkts_compl || bytes_compl)
		netdev_completed_queue(ndev, pkts_compl, bytes_compl);

	if (unlikely(netif_queue_stopped(ndev)) && (count < (TX_DESC_NUM - 1)))
		netif_wake_queue(ndev);

	return count;
}

static void hip04_start_tx_timer(struct hip04_priv *priv)
{
	unsigned long ns = priv->tx_coalesce_usecs * NSEC_PER_USEC / 2;

	/* allow timer to fire after half the time at the earliest */
	hrtimer_start_range_ns(&priv->tx_coalesce_timer, ns_to_ktime(ns),
			       ns, HRTIMER_MODE_REL);
}

static int hip04_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	struct net_device_stats *stats = &ndev->stats;
	unsigned int tx_head = priv->tx_head, count;
	struct tx_desc *desc = &priv->tx_desc[tx_head];
	dma_addr_t phys;

	smp_rmb();
	count = tx_count(tx_head, ACCESS_ONCE(priv->tx_tail));
	if (count == (TX_DESC_NUM - 1)) {
		netif_stop_queue(ndev);
		return NETDEV_TX_BUSY;
	}

	phys = dma_map_single(&ndev->dev, skb->data, skb->len, DMA_TO_DEVICE);
	if (dma_mapping_error(&ndev->dev, phys)) {
		dev_kfree_skb(skb);
		return NETDEV_TX_OK;
	}

	priv->tx_skb[tx_head] = skb;
	priv->tx_phys[tx_head] = phys;
	desc->send_addr = cpu_to_be32(phys);
	desc->send_size = cpu_to_be32(skb->len);
	desc->cfg = cpu_to_be32(TX_CLEAR_WB | TX_FINISH_CACHE_INV);
	phys = priv->tx_desc_dma + tx_head * sizeof(struct tx_desc);
	desc->wb_addr = cpu_to_be32(phys);
	skb_tx_timestamp(skb);

	hip04_set_xmit_desc(priv, phys);
	priv->tx_head = TX_NEXT(tx_head);
	count++;
	netdev_sent_queue(ndev, skb->len);

	stats->tx_bytes += skb->len;
	stats->tx_packets++;

	/* Ensure tx_head update visible to tx reclaim */
	smp_wmb();

	/* queue is getting full, better start cleaning up now */
	if (count >= priv->tx_coalesce_frames) {
		if (napi_schedule_prep(&priv->napi)) {
			/* disable rx interrupt and timer */
			priv->reg_inten &= ~(RCV_INT);
			writel_relaxed(DEF_INT_MASK & ~RCV_INT,
				       priv->base + PPE_INTEN);
			hrtimer_cancel(&priv->tx_coalesce_timer);
			__napi_schedule(&priv->napi);
		}
	} else if (!hrtimer_is_queued(&priv->tx_coalesce_timer)) {
		/* cleanup not pending yet, start a new timer */
		hip04_start_tx_timer(priv);
	}

	return NETDEV_TX_OK;
}

static int hip04_rx_poll(struct napi_struct *napi, int budget)
{
	struct hip04_priv *priv = container_of(napi, struct hip04_priv, napi);
	struct net_device *ndev = priv->ndev;
	struct net_device_stats *stats = &ndev->stats;
	unsigned int cnt = hip04_recv_cnt(priv);
	struct rx_desc *desc;
	struct sk_buff *skb;
	unsigned char *buf;
	bool last = false;
	dma_addr_t phys;
	int rx = 0;
	int tx_remaining;
	u16 len;
	u32 err;

	while (cnt && !last) {
		buf = priv->rx_buf[priv->rx_head];
		skb = build_skb(buf, priv->rx_buf_size);
		if (unlikely(!skb))
			net_dbg_ratelimited("build_skb failed\n");

		dma_unmap_single(&ndev->dev, priv->rx_phys[priv->rx_head],
				 RX_BUF_SIZE, DMA_FROM_DEVICE);
		priv->rx_phys[priv->rx_head] = 0;

		desc = (struct rx_desc *)skb->data;
		len = be16_to_cpu(desc->pkt_len);
		err = be32_to_cpu(desc->pkt_err);

		if (0 == len) {
			dev_kfree_skb_any(skb);
			last = true;
		} else if ((err & RX_PKT_ERR) || (len >= GMAC_MAX_PKT_LEN)) {
			dev_kfree_skb_any(skb);
			stats->rx_dropped++;
			stats->rx_errors++;
		} else {
			skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
			skb_put(skb, len);
			skb->protocol = eth_type_trans(skb, ndev);
			napi_gro_receive(&priv->napi, skb);
			stats->rx_packets++;
			stats->rx_bytes += len;
			rx++;
		}

		buf = netdev_alloc_frag(priv->rx_buf_size);
		if (!buf)
			goto done;
		phys = dma_map_single(&ndev->dev, buf,
				      RX_BUF_SIZE, DMA_FROM_DEVICE);
		if (dma_mapping_error(&ndev->dev, phys))
			goto done;
		priv->rx_buf[priv->rx_head] = buf;
		priv->rx_phys[priv->rx_head] = phys;
		hip04_set_recv_desc(priv, phys);

		priv->rx_head = RX_NEXT(priv->rx_head);
		if (rx >= budget)
			goto done;

		if (--cnt == 0)
			cnt = hip04_recv_cnt(priv);
	}

	if (!(priv->reg_inten & RCV_INT)) {
		/* enable rx interrupt */
		priv->reg_inten |= RCV_INT;
		writel_relaxed(priv->reg_inten, priv->base + PPE_INTEN);
	}
	napi_complete(napi);
done:
	/* clean up tx descriptors and start a new timer if necessary */
	tx_remaining = hip04_tx_reclaim(ndev, false);
	if (rx < budget && tx_remaining)
		hip04_start_tx_timer(priv);

	return rx;
}

static irqreturn_t hip04_mac_interrupt(int irq, void *dev_id)
{
	struct net_device *ndev = (struct net_device *)dev_id;
	struct hip04_priv *priv = netdev_priv(ndev);
	struct net_device_stats *stats = &ndev->stats;
	u32 ists = readl_relaxed(priv->base + PPE_INTSTS);

	if (!ists)
		return IRQ_NONE;

	writel_relaxed(DEF_INT_MASK, priv->base + PPE_RINT);

	if (unlikely(ists & DEF_INT_ERR)) {
		if (ists & (RCV_NOBUF | RCV_DROP)) {
			stats->rx_errors++;
			stats->rx_dropped++;
			netdev_err(ndev, "rx drop\n");
		}
		if (ists & TX_DROP) {
			stats->tx_dropped++;
			netdev_err(ndev, "tx drop\n");
		}
	}

	if (ists & RCV_INT && napi_schedule_prep(&priv->napi)) {
		/* disable rx interrupt */
		priv->reg_inten &= ~(RCV_INT);
		writel_relaxed(DEF_INT_MASK & ~RCV_INT, priv->base + PPE_INTEN);
		hrtimer_cancel(&priv->tx_coalesce_timer);
		__napi_schedule(&priv->napi);
	}

	return IRQ_HANDLED;
}

enum hrtimer_restart tx_done(struct hrtimer *hrtimer)
{
	struct hip04_priv *priv;

	priv = container_of(hrtimer, struct hip04_priv, tx_coalesce_timer);

	if (napi_schedule_prep(&priv->napi)) {
		/* disable rx interrupt */
		priv->reg_inten &= ~(RCV_INT);
		writel_relaxed(DEF_INT_MASK & ~RCV_INT, priv->base + PPE_INTEN);
		__napi_schedule(&priv->napi);
	}

	return HRTIMER_NORESTART;
}

static void hip04_adjust_link(struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	struct phy_device *phy = priv->phy;

	if ((priv->speed != phy->speed) || (priv->duplex != phy->duplex)) {
		hip04_config_port(ndev, phy->speed, phy->duplex);
		phy_print_status(phy);
	}
}

static int hip04_mac_open(struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	int i;

	priv->rx_head = 0;
	priv->tx_head = 0;
	priv->tx_tail = 0;
	hip04_reset_ppe(priv);

	for (i = 0; i < RX_DESC_NUM; i++) {
		dma_addr_t phys;

		phys = dma_map_single(&ndev->dev, priv->rx_buf[i],
				      RX_BUF_SIZE, DMA_FROM_DEVICE);
		if (dma_mapping_error(&ndev->dev, phys))
			return -EIO;

		priv->rx_phys[i] = phys;
		hip04_set_recv_desc(priv, phys);
	}

	if (priv->phy)
		phy_start(priv->phy);

	netdev_reset_queue(ndev);
	netif_start_queue(ndev);
	hip04_mac_enable(ndev);
	napi_enable(&priv->napi);

	return 0;
}

static int hip04_mac_stop(struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	int i;

	napi_disable(&priv->napi);
	netif_stop_queue(ndev);
	hip04_mac_disable(ndev);
	hip04_tx_reclaim(ndev, true);
	hip04_reset_ppe(priv);

	if (priv->phy)
		phy_stop(priv->phy);

	for (i = 0; i < RX_DESC_NUM; i++) {
		if (priv->rx_phys[i]) {
			dma_unmap_single(&ndev->dev, priv->rx_phys[i],
					 RX_BUF_SIZE, DMA_FROM_DEVICE);
			priv->rx_phys[i] = 0;
		}
	}

	return 0;
}

static void hip04_timeout(struct net_device *ndev)
{
	struct hip04_priv *priv = netdev_priv(ndev);

	schedule_work(&priv->tx_timeout_task);
}

static void hip04_tx_timeout_task(struct work_struct *work)
{
	struct hip04_priv *priv;

	priv = container_of(work, struct hip04_priv, tx_timeout_task);
	hip04_mac_stop(priv->ndev);
	hip04_mac_open(priv->ndev);
}

static struct net_device_stats *hip04_get_stats(struct net_device *ndev)
{
	return &ndev->stats;
}

static int hip04_get_coalesce(struct net_device *netdev,
			      struct ethtool_coalesce *ec)
{
	struct hip04_priv *priv = netdev_priv(netdev);

	ec->tx_coalesce_usecs = priv->tx_coalesce_usecs;
	ec->tx_max_coalesced_frames = priv->tx_coalesce_frames;

	return 0;
}

static int hip04_set_coalesce(struct net_device *netdev,
			      struct ethtool_coalesce *ec)
{
	struct hip04_priv *priv = netdev_priv(netdev);

	/* Check not supported parameters  */
	if ((ec->rx_max_coalesced_frames) || (ec->rx_coalesce_usecs_irq) ||
	    (ec->rx_max_coalesced_frames_irq) || (ec->tx_coalesce_usecs_irq) ||
	    (ec->use_adaptive_rx_coalesce) || (ec->use_adaptive_tx_coalesce) ||
	    (ec->pkt_rate_low) || (ec->rx_coalesce_usecs_low) ||
	    (ec->rx_max_coalesced_frames_low) || (ec->tx_coalesce_usecs_high) ||
	    (ec->tx_max_coalesced_frames_low) || (ec->pkt_rate_high) ||
	    (ec->tx_coalesce_usecs_low) || (ec->rx_coalesce_usecs_high) ||
	    (ec->rx_max_coalesced_frames_high) || (ec->rx_coalesce_usecs) ||
	    (ec->tx_max_coalesced_frames_irq) ||
	    (ec->stats_block_coalesce_usecs) ||
	    (ec->tx_max_coalesced_frames_high) || (ec->rate_sample_interval))
		return -EOPNOTSUPP;

	if ((ec->tx_coalesce_usecs > HIP04_MAX_TX_COALESCE_USECS ||
	     ec->tx_coalesce_usecs < HIP04_MIN_TX_COALESCE_USECS) ||
	    (ec->tx_max_coalesced_frames > HIP04_MAX_TX_COALESCE_FRAMES ||
	     ec->tx_max_coalesced_frames < HIP04_MIN_TX_COALESCE_FRAMES))
		return -EINVAL;

	priv->tx_coalesce_usecs = ec->tx_coalesce_usecs;
	priv->tx_coalesce_frames = ec->tx_max_coalesced_frames;

	return 0;
}

static void hip04_get_drvinfo(struct net_device *netdev,
			      struct ethtool_drvinfo *drvinfo)
{
	strlcpy(drvinfo->driver, DRV_NAME, sizeof(drvinfo->driver));
	strlcpy(drvinfo->version, DRV_VERSION, sizeof(drvinfo->version));
}

static struct ethtool_ops hip04_ethtool_ops = {
	.get_coalesce		= hip04_get_coalesce,
	.set_coalesce		= hip04_set_coalesce,
	.get_drvinfo		= hip04_get_drvinfo,
};

static struct net_device_ops hip04_netdev_ops = {
	.ndo_open		= hip04_mac_open,
	.ndo_stop		= hip04_mac_stop,
	.ndo_get_stats		= hip04_get_stats,
	.ndo_start_xmit		= hip04_mac_start_xmit,
	.ndo_set_mac_address	= hip04_set_mac_address,
	.ndo_tx_timeout         = hip04_timeout,
	.ndo_validate_addr	= eth_validate_addr,
	.ndo_change_mtu		= eth_change_mtu,
};

static int hip04_alloc_ring(struct net_device *ndev, struct device *d)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	int i;

	priv->tx_desc = dma_alloc_coherent(d,
					   TX_DESC_NUM * sizeof(struct tx_desc),
					   &priv->tx_desc_dma, GFP_KERNEL);
	if (!priv->tx_desc)
		return -ENOMEM;

	priv->rx_buf_size = RX_BUF_SIZE +
			    SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
	for (i = 0; i < RX_DESC_NUM; i++) {
		priv->rx_buf[i] = netdev_alloc_frag(priv->rx_buf_size);
		if (!priv->rx_buf[i])
			return -ENOMEM;
	}

	return 0;
}

static void hip04_free_ring(struct net_device *ndev, struct device *d)
{
	struct hip04_priv *priv = netdev_priv(ndev);
	int i;

	for (i = 0; i < RX_DESC_NUM; i++)
		if (priv->rx_buf[i])
			skb_free_frag(priv->rx_buf[i]);

	for (i = 0; i < TX_DESC_NUM; i++)
		if (priv->tx_skb[i])
			dev_kfree_skb_any(priv->tx_skb[i]);

	dma_free_coherent(d, TX_DESC_NUM * sizeof(struct tx_desc),
			  priv->tx_desc, priv->tx_desc_dma);
}

static int hip04_mac_probe(struct platform_device *pdev)
{
	struct device *d = &pdev->dev;
	struct device_node *node = d->of_node;
	struct of_phandle_args arg;
	struct net_device *ndev;
	struct hip04_priv *priv;
	struct resource *res;
	int irq;
	int ret;

	ndev = alloc_etherdev(sizeof(struct hip04_priv));
	if (!ndev)
		return -ENOMEM;

	priv = netdev_priv(ndev);
	priv->ndev = ndev;
	platform_set_drvdata(pdev, ndev);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	priv->base = devm_ioremap_resource(d, res);
	if (IS_ERR(priv->base)) {
		ret = PTR_ERR(priv->base);
		goto init_fail;
	}

	ret = of_parse_phandle_with_fixed_args(node, "port-handle", 2, 0, &arg);
	if (ret < 0) {
		dev_warn(d, "no port-handle\n");
		goto init_fail;
	}

	priv->port = arg.args[0];
	priv->chan = arg.args[1] * RX_DESC_NUM;

	hrtimer_init(&priv->tx_coalesce_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);

	/* BQL will try to keep the TX queue as short as possible, but it can't
	 * be faster than tx_coalesce_usecs, so we need a fast timeout here,
	 * but also long enough to gather up enough frames to ensure we don't
	 * get more interrupts than necessary.
	 * 200us is enough for 16 frames of 1500 bytes at gigabit ethernet rate
	 */
	priv->tx_coalesce_frames = TX_DESC_NUM * 3 / 4;
	priv->tx_coalesce_usecs = 200;
	priv->tx_coalesce_timer.function = tx_done;

	priv->map = syscon_node_to_regmap(arg.np);
	if (IS_ERR(priv->map)) {
		dev_warn(d, "no syscon hisilicon,hip04-ppe\n");
		ret = PTR_ERR(priv->map);
		goto init_fail;
	}

	priv->phy_mode = of_get_phy_mode(node);
	if (priv->phy_mode < 0) {
		dev_warn(d, "not find phy-mode\n");
		ret = -EINVAL;
		goto init_fail;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq <= 0) {
		ret = -EINVAL;
		goto init_fail;
	}

	ret = devm_request_irq(d, irq, hip04_mac_interrupt,
			       0, pdev->name, ndev);
	if (ret) {
		netdev_err(ndev, "devm_request_irq failed\n");
		goto init_fail;
	}

	priv->phy_node = of_parse_phandle(node, "phy-handle", 0);
	if (priv->phy_node) {
		priv->phy = of_phy_connect(ndev, priv->phy_node,
					   &hip04_adjust_link,
					   0, priv->phy_mode);
		if (!priv->phy) {
			ret = -EPROBE_DEFER;
			goto init_fail;
		}
	}

	INIT_WORK(&priv->tx_timeout_task, hip04_tx_timeout_task);

	ether_setup(ndev);
	ndev->netdev_ops = &hip04_netdev_ops;
	ndev->ethtool_ops = &hip04_ethtool_ops;
	ndev->watchdog_timeo = TX_TIMEOUT;
	ndev->priv_flags |= IFF_UNICAST_FLT;
	ndev->irq = irq;
	netif_napi_add(ndev, &priv->napi, hip04_rx_poll, NAPI_POLL_WEIGHT);
	SET_NETDEV_DEV(ndev, &pdev->dev);

	hip04_reset_ppe(priv);
	if (priv->phy_mode == PHY_INTERFACE_MODE_MII)
		hip04_config_port(ndev, SPEED_100, DUPLEX_FULL);

	hip04_config_fifo(priv);
	random_ether_addr(ndev->dev_addr);
	hip04_update_mac_address(ndev);

	ret = hip04_alloc_ring(ndev, d);
	if (ret) {
		netdev_err(ndev, "alloc ring fail\n");
		goto alloc_fail;
	}

	ret = register_netdev(ndev);
	if (ret) {
		free_netdev(ndev);
		goto alloc_fail;
	}

	return 0;

alloc_fail:
	hip04_free_ring(ndev, d);
init_fail:
	of_node_put(priv->phy_node);
	free_netdev(ndev);
	return ret;
}

static int hip04_remove(struct platform_device *pdev)
{
	struct net_device *ndev = platform_get_drvdata(pdev);
	struct hip04_priv *priv = netdev_priv(ndev);
	struct device *d = &pdev->dev;

	if (priv->phy)
		phy_disconnect(priv->phy);

	hip04_free_ring(ndev, d);
	unregister_netdev(ndev);
	free_irq(ndev->irq, ndev);
	of_node_put(priv->phy_node);
	cancel_work_sync(&priv->tx_timeout_task);
	free_netdev(ndev);

	return 0;
}

static const struct of_device_id hip04_mac_match[] = {
	{ .compatible = "hisilicon,hip04-mac" },
	{ }
};

MODULE_DEVICE_TABLE(of, hip04_mac_match);

static struct platform_driver hip04_mac_driver = {
	.probe	= hip04_mac_probe,
	.remove	= hip04_remove,
	.driver	= {
		.name		= DRV_NAME,
		.of_match_table	= hip04_mac_match,
	},
};
module_platform_driver(hip04_mac_driver);

MODULE_DESCRIPTION("HISILICON P04 Ethernet driver");
MODULE_LICENSE("GPL");