summaryrefslogblamecommitdiffstats
path: root/drivers/net/ethernet/renesas/ravb_main.c
blob: 78849dd4ef8e9463c2420c84cc583a927492df58 (plain) (tree)
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826





























                                                                              











                                     
                                                                              


























































































































































































                                                                             
                            









                                                    



                                                                           
                                                                               

                                                                




                                                                            





                                                               



                                                    





















                                                               
                            
                      

                     








                                                                        







                                                                          





                                                                                







                                                                          

















































































































































































































                                                                                



                                                                              


















                                                                               


                                                                             




































                                                                                



                                                                           




                                                                              





































































































































































                                                                                                              


                                                  



















































































































































































































































































































































                                                                                

                                           




























                                                                                                   


                                                 








                                                         

                                                      











                                                                        
                                                           








































                                                                               


                                         




                                        
                                  


                 


                                   






























                                                                           


                                   









                                      


                                         













                                                                                















































                                                                               
                                                                          

































































































                                                                                


                                   





































































































































































































































































































































































































                                                                                         
/* Renesas Ethernet AVB device driver
 *
 * Copyright (C) 2014-2015 Renesas Electronics Corporation
 * Copyright (C) 2015 Renesas Solutions Corp.
 * Copyright (C) 2015 Cogent Embedded, Inc. <source@cogentembedded.com>
 *
 * Based on the SuperH Ethernet driver
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License version 2,
 * as published by the Free Software Foundation.
 */

#include <linux/cache.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/if_vlan.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/net_tstamp.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

#include "ravb.h"

#define RAVB_DEF_MSG_ENABLE \
		(NETIF_MSG_LINK	  | \
		 NETIF_MSG_TIMER  | \
		 NETIF_MSG_RX_ERR | \
		 NETIF_MSG_TX_ERR)

int ravb_wait(struct net_device *ndev, enum ravb_reg reg, u32 mask, u32 value)
{
	int i;

	for (i = 0; i < 10000; i++) {
		if ((ravb_read(ndev, reg) & mask) == value)
			return 0;
		udelay(10);
	}
	return -ETIMEDOUT;
}

static int ravb_config(struct net_device *ndev)
{
	int error;

	/* Set config mode */
	ravb_write(ndev, (ravb_read(ndev, CCC) & ~CCC_OPC) | CCC_OPC_CONFIG,
		   CCC);
	/* Check if the operating mode is changed to the config mode */
	error = ravb_wait(ndev, CSR, CSR_OPS, CSR_OPS_CONFIG);
	if (error)
		netdev_err(ndev, "failed to switch device to config mode\n");

	return error;
}

static void ravb_set_duplex(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	u32 ecmr = ravb_read(ndev, ECMR);

	if (priv->duplex)	/* Full */
		ecmr |=  ECMR_DM;
	else			/* Half */
		ecmr &= ~ECMR_DM;
	ravb_write(ndev, ecmr, ECMR);
}

static void ravb_set_rate(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);

	switch (priv->speed) {
	case 100:		/* 100BASE */
		ravb_write(ndev, GECMR_SPEED_100, GECMR);
		break;
	case 1000:		/* 1000BASE */
		ravb_write(ndev, GECMR_SPEED_1000, GECMR);
		break;
	default:
		break;
	}
}

static void ravb_set_buffer_align(struct sk_buff *skb)
{
	u32 reserve = (unsigned long)skb->data & (RAVB_ALIGN - 1);

	if (reserve)
		skb_reserve(skb, RAVB_ALIGN - reserve);
}

/* Get MAC address from the MAC address registers
 *
 * Ethernet AVB device doesn't have ROM for MAC address.
 * This function gets the MAC address that was used by a bootloader.
 */
static void ravb_read_mac_address(struct net_device *ndev, const u8 *mac)
{
	if (mac) {
		ether_addr_copy(ndev->dev_addr, mac);
	} else {
		ndev->dev_addr[0] = (ravb_read(ndev, MAHR) >> 24);
		ndev->dev_addr[1] = (ravb_read(ndev, MAHR) >> 16) & 0xFF;
		ndev->dev_addr[2] = (ravb_read(ndev, MAHR) >> 8) & 0xFF;
		ndev->dev_addr[3] = (ravb_read(ndev, MAHR) >> 0) & 0xFF;
		ndev->dev_addr[4] = (ravb_read(ndev, MALR) >> 8) & 0xFF;
		ndev->dev_addr[5] = (ravb_read(ndev, MALR) >> 0) & 0xFF;
	}
}

static void ravb_mdio_ctrl(struct mdiobb_ctrl *ctrl, u32 mask, int set)
{
	struct ravb_private *priv = container_of(ctrl, struct ravb_private,
						 mdiobb);
	u32 pir = ravb_read(priv->ndev, PIR);

	if (set)
		pir |=  mask;
	else
		pir &= ~mask;
	ravb_write(priv->ndev, pir, PIR);
}

/* MDC pin control */
static void ravb_set_mdc(struct mdiobb_ctrl *ctrl, int level)
{
	ravb_mdio_ctrl(ctrl, PIR_MDC, level);
}

/* Data I/O pin control */
static void ravb_set_mdio_dir(struct mdiobb_ctrl *ctrl, int output)
{
	ravb_mdio_ctrl(ctrl, PIR_MMD, output);
}

/* Set data bit */
static void ravb_set_mdio_data(struct mdiobb_ctrl *ctrl, int value)
{
	ravb_mdio_ctrl(ctrl, PIR_MDO, value);
}

/* Get data bit */
static int ravb_get_mdio_data(struct mdiobb_ctrl *ctrl)
{
	struct ravb_private *priv = container_of(ctrl, struct ravb_private,
						 mdiobb);

	return (ravb_read(priv->ndev, PIR) & PIR_MDI) != 0;
}

/* MDIO bus control struct */
static struct mdiobb_ops bb_ops = {
	.owner = THIS_MODULE,
	.set_mdc = ravb_set_mdc,
	.set_mdio_dir = ravb_set_mdio_dir,
	.set_mdio_data = ravb_set_mdio_data,
	.get_mdio_data = ravb_get_mdio_data,
};

/* Free skb's and DMA buffers for Ethernet AVB */
static void ravb_ring_free(struct net_device *ndev, int q)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int ring_size;
	int i;

	/* Free RX skb ringbuffer */
	if (priv->rx_skb[q]) {
		for (i = 0; i < priv->num_rx_ring[q]; i++)
			dev_kfree_skb(priv->rx_skb[q][i]);
	}
	kfree(priv->rx_skb[q]);
	priv->rx_skb[q] = NULL;

	/* Free TX skb ringbuffer */
	if (priv->tx_skb[q]) {
		for (i = 0; i < priv->num_tx_ring[q]; i++)
			dev_kfree_skb(priv->tx_skb[q][i]);
	}
	kfree(priv->tx_skb[q]);
	priv->tx_skb[q] = NULL;

	/* Free aligned TX buffers */
	if (priv->tx_buffers[q]) {
		for (i = 0; i < priv->num_tx_ring[q]; i++)
			kfree(priv->tx_buffers[q][i]);
	}
	kfree(priv->tx_buffers[q]);
	priv->tx_buffers[q] = NULL;

	if (priv->rx_ring[q]) {
		ring_size = sizeof(struct ravb_ex_rx_desc) *
			    (priv->num_rx_ring[q] + 1);
		dma_free_coherent(NULL, ring_size, priv->rx_ring[q],
				  priv->rx_desc_dma[q]);
		priv->rx_ring[q] = NULL;
	}

	if (priv->tx_ring[q]) {
		ring_size = sizeof(struct ravb_tx_desc) *
			    (priv->num_tx_ring[q] + 1);
		dma_free_coherent(NULL, ring_size, priv->tx_ring[q],
				  priv->tx_desc_dma[q]);
		priv->tx_ring[q] = NULL;
	}
}

/* Format skb and descriptor buffer for Ethernet AVB */
static void ravb_ring_format(struct net_device *ndev, int q)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct ravb_ex_rx_desc *rx_desc = NULL;
	struct ravb_tx_desc *tx_desc = NULL;
	struct ravb_desc *desc = NULL;
	int rx_ring_size = sizeof(*rx_desc) * priv->num_rx_ring[q];
	int tx_ring_size = sizeof(*tx_desc) * priv->num_tx_ring[q];
	dma_addr_t dma_addr;
	int i;

	priv->cur_rx[q] = 0;
	priv->cur_tx[q] = 0;
	priv->dirty_rx[q] = 0;
	priv->dirty_tx[q] = 0;

	memset(priv->rx_ring[q], 0, rx_ring_size);
	/* Build RX ring buffer */
	for (i = 0; i < priv->num_rx_ring[q]; i++) {
		/* RX descriptor */
		rx_desc = &priv->rx_ring[q][i];
		/* The size of the buffer should be on 16-byte boundary. */
		rx_desc->ds_cc = cpu_to_le16(ALIGN(PKT_BUF_SZ, 16));
		dma_addr = dma_map_single(&ndev->dev, priv->rx_skb[q][i]->data,
					  ALIGN(PKT_BUF_SZ, 16),
					  DMA_FROM_DEVICE);
		/* We just set the data size to 0 for a failed mapping which
		 * should prevent DMA from happening...
		 */
		if (dma_mapping_error(&ndev->dev, dma_addr))
			rx_desc->ds_cc = cpu_to_le16(0);
		rx_desc->dptr = cpu_to_le32(dma_addr);
		rx_desc->die_dt = DT_FEMPTY;
	}
	rx_desc = &priv->rx_ring[q][i];
	rx_desc->dptr = cpu_to_le32((u32)priv->rx_desc_dma[q]);
	rx_desc->die_dt = DT_LINKFIX; /* type */

	memset(priv->tx_ring[q], 0, tx_ring_size);
	/* Build TX ring buffer */
	for (i = 0; i < priv->num_tx_ring[q]; i++) {
		tx_desc = &priv->tx_ring[q][i];
		tx_desc->die_dt = DT_EEMPTY;
	}
	tx_desc = &priv->tx_ring[q][i];
	tx_desc->dptr = cpu_to_le32((u32)priv->tx_desc_dma[q]);
	tx_desc->die_dt = DT_LINKFIX; /* type */

	/* RX descriptor base address for best effort */
	desc = &priv->desc_bat[RX_QUEUE_OFFSET + q];
	desc->die_dt = DT_LINKFIX; /* type */
	desc->dptr = cpu_to_le32((u32)priv->rx_desc_dma[q]);

	/* TX descriptor base address for best effort */
	desc = &priv->desc_bat[q];
	desc->die_dt = DT_LINKFIX; /* type */
	desc->dptr = cpu_to_le32((u32)priv->tx_desc_dma[q]);
}

/* Init skb and descriptor buffer for Ethernet AVB */
static int ravb_ring_init(struct net_device *ndev, int q)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct sk_buff *skb;
	int ring_size;
	void *buffer;
	int i;

	/* Allocate RX and TX skb rings */
	priv->rx_skb[q] = kcalloc(priv->num_rx_ring[q],
				  sizeof(*priv->rx_skb[q]), GFP_KERNEL);
	priv->tx_skb[q] = kcalloc(priv->num_tx_ring[q],
				  sizeof(*priv->tx_skb[q]), GFP_KERNEL);
	if (!priv->rx_skb[q] || !priv->tx_skb[q])
		goto error;

	for (i = 0; i < priv->num_rx_ring[q]; i++) {
		skb = netdev_alloc_skb(ndev, PKT_BUF_SZ + RAVB_ALIGN - 1);
		if (!skb)
			goto error;
		ravb_set_buffer_align(skb);
		priv->rx_skb[q][i] = skb;
	}

	/* Allocate rings for the aligned buffers */
	priv->tx_buffers[q] = kcalloc(priv->num_tx_ring[q],
				      sizeof(*priv->tx_buffers[q]), GFP_KERNEL);
	if (!priv->tx_buffers[q])
		goto error;

	for (i = 0; i < priv->num_tx_ring[q]; i++) {
		buffer = kmalloc(PKT_BUF_SZ + RAVB_ALIGN - 1, GFP_KERNEL);
		if (!buffer)
			goto error;
		/* Aligned TX buffer */
		priv->tx_buffers[q][i] = buffer;
	}

	/* Allocate all RX descriptors. */
	ring_size = sizeof(struct ravb_ex_rx_desc) * (priv->num_rx_ring[q] + 1);
	priv->rx_ring[q] = dma_alloc_coherent(NULL, ring_size,
					      &priv->rx_desc_dma[q],
					      GFP_KERNEL);
	if (!priv->rx_ring[q])
		goto error;

	priv->dirty_rx[q] = 0;

	/* Allocate all TX descriptors. */
	ring_size = sizeof(struct ravb_tx_desc) * (priv->num_tx_ring[q] + 1);
	priv->tx_ring[q] = dma_alloc_coherent(NULL, ring_size,
					      &priv->tx_desc_dma[q],
					      GFP_KERNEL);
	if (!priv->tx_ring[q])
		goto error;

	return 0;

error:
	ravb_ring_free(ndev, q);

	return -ENOMEM;
}

/* E-MAC init function */
static void ravb_emac_init(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	u32 ecmr;

	/* Receive frame limit set register */
	ravb_write(ndev, ndev->mtu + ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN, RFLR);

	/* PAUSE prohibition */
	ecmr =  ravb_read(ndev, ECMR);
	ecmr &= ECMR_DM;
	ecmr |= ECMR_ZPF | (priv->duplex ? ECMR_DM : 0) | ECMR_TE | ECMR_RE;
	ravb_write(ndev, ecmr, ECMR);

	ravb_set_rate(ndev);

	/* Set MAC address */
	ravb_write(ndev,
		   (ndev->dev_addr[0] << 24) | (ndev->dev_addr[1] << 16) |
		   (ndev->dev_addr[2] << 8)  | (ndev->dev_addr[3]), MAHR);
	ravb_write(ndev,
		   (ndev->dev_addr[4] << 8)  | (ndev->dev_addr[5]), MALR);

	ravb_write(ndev, 1, MPR);

	/* E-MAC status register clear */
	ravb_write(ndev, ECSR_ICD | ECSR_MPD, ECSR);

	/* E-MAC interrupt enable register */
	ravb_write(ndev, ECSIPR_ICDIP | ECSIPR_MPDIP | ECSIPR_LCHNGIP, ECSIPR);
}

/* Device init function for Ethernet AVB */
static int ravb_dmac_init(struct net_device *ndev)
{
	int error;

	/* Set CONFIG mode */
	error = ravb_config(ndev);
	if (error)
		return error;

	error = ravb_ring_init(ndev, RAVB_BE);
	if (error)
		return error;
	error = ravb_ring_init(ndev, RAVB_NC);
	if (error) {
		ravb_ring_free(ndev, RAVB_BE);
		return error;
	}

	/* Descriptor format */
	ravb_ring_format(ndev, RAVB_BE);
	ravb_ring_format(ndev, RAVB_NC);

#if defined(__LITTLE_ENDIAN)
	ravb_write(ndev, ravb_read(ndev, CCC) & ~CCC_BOC, CCC);
#else
	ravb_write(ndev, ravb_read(ndev, CCC) | CCC_BOC, CCC);
#endif

	/* Set AVB RX */
	ravb_write(ndev, RCR_EFFS | RCR_ENCF | RCR_ETS0 | 0x18000000, RCR);

	/* Set FIFO size */
	ravb_write(ndev, TGC_TQP_AVBMODE1 | 0x00222200, TGC);

	/* Timestamp enable */
	ravb_write(ndev, TCCR_TFEN, TCCR);

	/* Interrupt enable: */
	/* Frame receive */
	ravb_write(ndev, RIC0_FRE0 | RIC0_FRE1, RIC0);
	/* Receive FIFO full warning */
	ravb_write(ndev, RIC1_RFWE, RIC1);
	/* Receive FIFO full error, descriptor empty */
	ravb_write(ndev, RIC2_QFE0 | RIC2_QFE1 | RIC2_RFFE, RIC2);
	/* Frame transmitted, timestamp FIFO updated */
	ravb_write(ndev, TIC_FTE0 | TIC_FTE1 | TIC_TFUE, TIC);

	/* Setting the control will start the AVB-DMAC process. */
	ravb_write(ndev, (ravb_read(ndev, CCC) & ~CCC_OPC) | CCC_OPC_OPERATION,
		   CCC);

	return 0;
}

/* Free TX skb function for AVB-IP */
static int ravb_tx_free(struct net_device *ndev, int q)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct net_device_stats *stats = &priv->stats[q];
	struct ravb_tx_desc *desc;
	int free_num = 0;
	int entry = 0;
	u32 size;

	for (; priv->cur_tx[q] - priv->dirty_tx[q] > 0; priv->dirty_tx[q]++) {
		entry = priv->dirty_tx[q] % priv->num_tx_ring[q];
		desc = &priv->tx_ring[q][entry];
		if (desc->die_dt != DT_FEMPTY)
			break;
		/* Descriptor type must be checked before all other reads */
		dma_rmb();
		size = le16_to_cpu(desc->ds_tagl) & TX_DS;
		/* Free the original skb. */
		if (priv->tx_skb[q][entry]) {
			dma_unmap_single(&ndev->dev, le32_to_cpu(desc->dptr),
					 size, DMA_TO_DEVICE);
			dev_kfree_skb_any(priv->tx_skb[q][entry]);
			priv->tx_skb[q][entry] = NULL;
			free_num++;
		}
		stats->tx_packets++;
		stats->tx_bytes += size;
		desc->die_dt = DT_EEMPTY;
	}
	return free_num;
}

static void ravb_get_tx_tstamp(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct ravb_tstamp_skb *ts_skb, *ts_skb2;
	struct skb_shared_hwtstamps shhwtstamps;
	struct sk_buff *skb;
	struct timespec64 ts;
	u16 tag, tfa_tag;
	int count;
	u32 tfa2;

	count = (ravb_read(ndev, TSR) & TSR_TFFL) >> 8;
	while (count--) {
		tfa2 = ravb_read(ndev, TFA2);
		tfa_tag = (tfa2 & TFA2_TST) >> 16;
		ts.tv_nsec = (u64)ravb_read(ndev, TFA0);
		ts.tv_sec = ((u64)(tfa2 & TFA2_TSV) << 32) |
			    ravb_read(ndev, TFA1);
		memset(&shhwtstamps, 0, sizeof(shhwtstamps));
		shhwtstamps.hwtstamp = timespec64_to_ktime(ts);
		list_for_each_entry_safe(ts_skb, ts_skb2, &priv->ts_skb_list,
					 list) {
			skb = ts_skb->skb;
			tag = ts_skb->tag;
			list_del(&ts_skb->list);
			kfree(ts_skb);
			if (tag == tfa_tag) {
				skb_tstamp_tx(skb, &shhwtstamps);
				break;
			}
		}
		ravb_write(ndev, ravb_read(ndev, TCCR) | TCCR_TFR, TCCR);
	}
}

/* Packet receive function for Ethernet AVB */
static bool ravb_rx(struct net_device *ndev, int *quota, int q)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int entry = priv->cur_rx[q] % priv->num_rx_ring[q];
	int boguscnt = (priv->dirty_rx[q] + priv->num_rx_ring[q]) -
			priv->cur_rx[q];
	struct net_device_stats *stats = &priv->stats[q];
	struct ravb_ex_rx_desc *desc;
	struct sk_buff *skb;
	dma_addr_t dma_addr;
	struct timespec64 ts;
	u16 pkt_len = 0;
	u8  desc_status;
	int limit;

	boguscnt = min(boguscnt, *quota);
	limit = boguscnt;
	desc = &priv->rx_ring[q][entry];
	while (desc->die_dt != DT_FEMPTY) {
		/* Descriptor type must be checked before all other reads */
		dma_rmb();
		desc_status = desc->msc;
		pkt_len = le16_to_cpu(desc->ds_cc) & RX_DS;

		if (--boguscnt < 0)
			break;

		/* We use 0-byte descriptors to mark the DMA mapping errors */
		if (!pkt_len)
			continue;

		if (desc_status & MSC_MC)
			stats->multicast++;

		if (desc_status & (MSC_CRC | MSC_RFE | MSC_RTSF | MSC_RTLF |
				   MSC_CEEF)) {
			stats->rx_errors++;
			if (desc_status & MSC_CRC)
				stats->rx_crc_errors++;
			if (desc_status & MSC_RFE)
				stats->rx_frame_errors++;
			if (desc_status & (MSC_RTLF | MSC_RTSF))
				stats->rx_length_errors++;
			if (desc_status & MSC_CEEF)
				stats->rx_missed_errors++;
		} else {
			u32 get_ts = priv->tstamp_rx_ctrl & RAVB_RXTSTAMP_TYPE;

			skb = priv->rx_skb[q][entry];
			priv->rx_skb[q][entry] = NULL;
			dma_unmap_single(&ndev->dev, le32_to_cpu(desc->dptr),
					 ALIGN(PKT_BUF_SZ, 16),
					 DMA_FROM_DEVICE);
			get_ts &= (q == RAVB_NC) ?
					RAVB_RXTSTAMP_TYPE_V2_L2_EVENT :
					~RAVB_RXTSTAMP_TYPE_V2_L2_EVENT;
			if (get_ts) {
				struct skb_shared_hwtstamps *shhwtstamps;

				shhwtstamps = skb_hwtstamps(skb);
				memset(shhwtstamps, 0, sizeof(*shhwtstamps));
				ts.tv_sec = ((u64) le16_to_cpu(desc->ts_sh) <<
					     32) | le32_to_cpu(desc->ts_sl);
				ts.tv_nsec = le32_to_cpu(desc->ts_n);
				shhwtstamps->hwtstamp = timespec64_to_ktime(ts);
			}
			skb_put(skb, pkt_len);
			skb->protocol = eth_type_trans(skb, ndev);
			napi_gro_receive(&priv->napi[q], skb);
			stats->rx_packets++;
			stats->rx_bytes += pkt_len;
		}

		entry = (++priv->cur_rx[q]) % priv->num_rx_ring[q];
		desc = &priv->rx_ring[q][entry];
	}

	/* Refill the RX ring buffers. */
	for (; priv->cur_rx[q] - priv->dirty_rx[q] > 0; priv->dirty_rx[q]++) {
		entry = priv->dirty_rx[q] % priv->num_rx_ring[q];
		desc = &priv->rx_ring[q][entry];
		/* The size of the buffer should be on 16-byte boundary. */
		desc->ds_cc = cpu_to_le16(ALIGN(PKT_BUF_SZ, 16));

		if (!priv->rx_skb[q][entry]) {
			skb = netdev_alloc_skb(ndev,
					       PKT_BUF_SZ + RAVB_ALIGN - 1);
			if (!skb)
				break;	/* Better luck next round. */
			ravb_set_buffer_align(skb);
			dma_addr = dma_map_single(&ndev->dev, skb->data,
						  le16_to_cpu(desc->ds_cc),
						  DMA_FROM_DEVICE);
			skb_checksum_none_assert(skb);
			/* We just set the data size to 0 for a failed mapping
			 * which should prevent DMA  from happening...
			 */
			if (dma_mapping_error(&ndev->dev, dma_addr))
				desc->ds_cc = cpu_to_le16(0);
			desc->dptr = cpu_to_le32(dma_addr);
			priv->rx_skb[q][entry] = skb;
		}
		/* Descriptor type must be set after all the above writes */
		dma_wmb();
		desc->die_dt = DT_FEMPTY;
	}

	*quota -= limit - (++boguscnt);

	return boguscnt <= 0;
}

static void ravb_rcv_snd_disable(struct net_device *ndev)
{
	/* Disable TX and RX */
	ravb_write(ndev, ravb_read(ndev, ECMR) & ~(ECMR_RE | ECMR_TE), ECMR);
}

static void ravb_rcv_snd_enable(struct net_device *ndev)
{
	/* Enable TX and RX */
	ravb_write(ndev, ravb_read(ndev, ECMR) | ECMR_RE | ECMR_TE, ECMR);
}

/* function for waiting dma process finished */
static int ravb_stop_dma(struct net_device *ndev)
{
	int error;

	/* Wait for stopping the hardware TX process */
	error = ravb_wait(ndev, TCCR,
			  TCCR_TSRQ0 | TCCR_TSRQ1 | TCCR_TSRQ2 | TCCR_TSRQ3, 0);
	if (error)
		return error;

	error = ravb_wait(ndev, CSR, CSR_TPO0 | CSR_TPO1 | CSR_TPO2 | CSR_TPO3,
			  0);
	if (error)
		return error;

	/* Stop the E-MAC's RX/TX processes. */
	ravb_rcv_snd_disable(ndev);

	/* Wait for stopping the RX DMA process */
	error = ravb_wait(ndev, CSR, CSR_RPO, 0);
	if (error)
		return error;

	/* Stop AVB-DMAC process */
	return ravb_config(ndev);
}

/* E-MAC interrupt handler */
static void ravb_emac_interrupt(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	u32 ecsr, psr;

	ecsr = ravb_read(ndev, ECSR);
	ravb_write(ndev, ecsr, ECSR);	/* clear interrupt */
	if (ecsr & ECSR_ICD)
		ndev->stats.tx_carrier_errors++;
	if (ecsr & ECSR_LCHNG) {
		/* Link changed */
		if (priv->no_avb_link)
			return;
		psr = ravb_read(ndev, PSR);
		if (priv->avb_link_active_low)
			psr ^= PSR_LMON;
		if (!(psr & PSR_LMON)) {
			/* DIsable RX and TX */
			ravb_rcv_snd_disable(ndev);
		} else {
			/* Enable RX and TX */
			ravb_rcv_snd_enable(ndev);
		}
	}
}

/* Error interrupt handler */
static void ravb_error_interrupt(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	u32 eis, ris2;

	eis = ravb_read(ndev, EIS);
	ravb_write(ndev, ~EIS_QFS, EIS);
	if (eis & EIS_QFS) {
		ris2 = ravb_read(ndev, RIS2);
		ravb_write(ndev, ~(RIS2_QFF0 | RIS2_RFFF), RIS2);

		/* Receive Descriptor Empty int */
		if (ris2 & RIS2_QFF0)
			priv->stats[RAVB_BE].rx_over_errors++;

		    /* Receive Descriptor Empty int */
		if (ris2 & RIS2_QFF1)
			priv->stats[RAVB_NC].rx_over_errors++;

		/* Receive FIFO Overflow int */
		if (ris2 & RIS2_RFFF)
			priv->rx_fifo_errors++;
	}
}

static irqreturn_t ravb_interrupt(int irq, void *dev_id)
{
	struct net_device *ndev = dev_id;
	struct ravb_private *priv = netdev_priv(ndev);
	irqreturn_t result = IRQ_NONE;
	u32 iss;

	spin_lock(&priv->lock);
	/* Get interrupt status */
	iss = ravb_read(ndev, ISS);

	/* Received and transmitted interrupts */
	if (iss & (ISS_FRS | ISS_FTS | ISS_TFUS)) {
		u32 ris0 = ravb_read(ndev, RIS0);
		u32 ric0 = ravb_read(ndev, RIC0);
		u32 tis  = ravb_read(ndev, TIS);
		u32 tic  = ravb_read(ndev, TIC);
		int q;

		/* Timestamp updated */
		if (tis & TIS_TFUF) {
			ravb_write(ndev, ~TIS_TFUF, TIS);
			ravb_get_tx_tstamp(ndev);
			result = IRQ_HANDLED;
		}

		/* Network control and best effort queue RX/TX */
		for (q = RAVB_NC; q >= RAVB_BE; q--) {
			if (((ris0 & ric0) & BIT(q)) ||
			    ((tis  & tic)  & BIT(q))) {
				if (napi_schedule_prep(&priv->napi[q])) {
					/* Mask RX and TX interrupts */
					ravb_write(ndev, ric0 & ~BIT(q), RIC0);
					ravb_write(ndev, tic  & ~BIT(q), TIC);
					__napi_schedule(&priv->napi[q]);
				} else {
					netdev_warn(ndev,
						    "ignoring interrupt, rx status 0x%08x, rx mask 0x%08x,\n",
						    ris0, ric0);
					netdev_warn(ndev,
						    "                    tx status 0x%08x, tx mask 0x%08x.\n",
						    tis, tic);
				}
				result = IRQ_HANDLED;
			}
		}
	}

	/* E-MAC status summary */
	if (iss & ISS_MS) {
		ravb_emac_interrupt(ndev);
		result = IRQ_HANDLED;
	}

	/* Error status summary */
	if (iss & ISS_ES) {
		ravb_error_interrupt(ndev);
		result = IRQ_HANDLED;
	}

	if (iss & ISS_CGIS)
		result = ravb_ptp_interrupt(ndev);

	mmiowb();
	spin_unlock(&priv->lock);
	return result;
}

static int ravb_poll(struct napi_struct *napi, int budget)
{
	struct net_device *ndev = napi->dev;
	struct ravb_private *priv = netdev_priv(ndev);
	unsigned long flags;
	int q = napi - priv->napi;
	int mask = BIT(q);
	int quota = budget;
	u32 ris0, tis;

	for (;;) {
		tis = ravb_read(ndev, TIS);
		ris0 = ravb_read(ndev, RIS0);
		if (!((ris0 & mask) || (tis & mask)))
			break;

		/* Processing RX Descriptor Ring */
		if (ris0 & mask) {
			/* Clear RX interrupt */
			ravb_write(ndev, ~mask, RIS0);
			if (ravb_rx(ndev, &quota, q))
				goto out;
		}
		/* Processing TX Descriptor Ring */
		if (tis & mask) {
			spin_lock_irqsave(&priv->lock, flags);
			/* Clear TX interrupt */
			ravb_write(ndev, ~mask, TIS);
			ravb_tx_free(ndev, q);
			netif_wake_subqueue(ndev, q);
			mmiowb();
			spin_unlock_irqrestore(&priv->lock, flags);
		}
	}

	napi_complete(napi);

	/* Re-enable RX/TX interrupts */
	spin_lock_irqsave(&priv->lock, flags);
	ravb_write(ndev, ravb_read(ndev, RIC0) | mask, RIC0);
	ravb_write(ndev, ravb_read(ndev, TIC)  | mask,  TIC);
	mmiowb();
	spin_unlock_irqrestore(&priv->lock, flags);

	/* Receive error message handling */
	priv->rx_over_errors =  priv->stats[RAVB_BE].rx_over_errors;
	priv->rx_over_errors += priv->stats[RAVB_NC].rx_over_errors;
	if (priv->rx_over_errors != ndev->stats.rx_over_errors) {
		ndev->stats.rx_over_errors = priv->rx_over_errors;
		netif_err(priv, rx_err, ndev, "Receive Descriptor Empty\n");
	}
	if (priv->rx_fifo_errors != ndev->stats.rx_fifo_errors) {
		ndev->stats.rx_fifo_errors = priv->rx_fifo_errors;
		netif_err(priv, rx_err, ndev, "Receive FIFO Overflow\n");
	}
out:
	return budget - quota;
}

/* PHY state control function */
static void ravb_adjust_link(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct phy_device *phydev = priv->phydev;
	bool new_state = false;

	if (phydev->link) {
		if (phydev->duplex != priv->duplex) {
			new_state = true;
			priv->duplex = phydev->duplex;
			ravb_set_duplex(ndev);
		}

		if (phydev->speed != priv->speed) {
			new_state = true;
			priv->speed = phydev->speed;
			ravb_set_rate(ndev);
		}
		if (!priv->link) {
			ravb_write(ndev, ravb_read(ndev, ECMR) & ~ECMR_TXF,
				   ECMR);
			new_state = true;
			priv->link = phydev->link;
			if (priv->no_avb_link)
				ravb_rcv_snd_enable(ndev);
		}
	} else if (priv->link) {
		new_state = true;
		priv->link = 0;
		priv->speed = 0;
		priv->duplex = -1;
		if (priv->no_avb_link)
			ravb_rcv_snd_disable(ndev);
	}

	if (new_state && netif_msg_link(priv))
		phy_print_status(phydev);
}

/* PHY init function */
static int ravb_phy_init(struct net_device *ndev)
{
	struct device_node *np = ndev->dev.parent->of_node;
	struct ravb_private *priv = netdev_priv(ndev);
	struct phy_device *phydev;
	struct device_node *pn;

	priv->link = 0;
	priv->speed = 0;
	priv->duplex = -1;

	/* Try connecting to PHY */
	pn = of_parse_phandle(np, "phy-handle", 0);
	phydev = of_phy_connect(ndev, pn, ravb_adjust_link, 0,
				priv->phy_interface);
	if (!phydev) {
		netdev_err(ndev, "failed to connect PHY\n");
		return -ENOENT;
	}

	netdev_info(ndev, "attached PHY %d (IRQ %d) to driver %s\n",
		    phydev->addr, phydev->irq, phydev->drv->name);

	priv->phydev = phydev;

	return 0;
}

/* PHY control start function */
static int ravb_phy_start(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int error;

	error = ravb_phy_init(ndev);
	if (error)
		return error;

	phy_start(priv->phydev);

	return 0;
}

static int ravb_get_settings(struct net_device *ndev, struct ethtool_cmd *ecmd)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int error = -ENODEV;
	unsigned long flags;

	if (priv->phydev) {
		spin_lock_irqsave(&priv->lock, flags);
		error = phy_ethtool_gset(priv->phydev, ecmd);
		spin_unlock_irqrestore(&priv->lock, flags);
	}

	return error;
}

static int ravb_set_settings(struct net_device *ndev, struct ethtool_cmd *ecmd)
{
	struct ravb_private *priv = netdev_priv(ndev);
	unsigned long flags;
	int error;

	if (!priv->phydev)
		return -ENODEV;

	spin_lock_irqsave(&priv->lock, flags);

	/* Disable TX and RX */
	ravb_rcv_snd_disable(ndev);

	error = phy_ethtool_sset(priv->phydev, ecmd);
	if (error)
		goto error_exit;

	if (ecmd->duplex == DUPLEX_FULL)
		priv->duplex = 1;
	else
		priv->duplex = 0;

	ravb_set_duplex(ndev);

error_exit:
	mdelay(1);

	/* Enable TX and RX */
	ravb_rcv_snd_enable(ndev);

	mmiowb();
	spin_unlock_irqrestore(&priv->lock, flags);

	return error;
}

static int ravb_nway_reset(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int error = -ENODEV;
	unsigned long flags;

	if (priv->phydev) {
		spin_lock_irqsave(&priv->lock, flags);
		error = phy_start_aneg(priv->phydev);
		spin_unlock_irqrestore(&priv->lock, flags);
	}

	return error;
}

static u32 ravb_get_msglevel(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);

	return priv->msg_enable;
}

static void ravb_set_msglevel(struct net_device *ndev, u32 value)
{
	struct ravb_private *priv = netdev_priv(ndev);

	priv->msg_enable = value;
}

static const char ravb_gstrings_stats[][ETH_GSTRING_LEN] = {
	"rx_queue_0_current",
	"tx_queue_0_current",
	"rx_queue_0_dirty",
	"tx_queue_0_dirty",
	"rx_queue_0_packets",
	"tx_queue_0_packets",
	"rx_queue_0_bytes",
	"tx_queue_0_bytes",
	"rx_queue_0_mcast_packets",
	"rx_queue_0_errors",
	"rx_queue_0_crc_errors",
	"rx_queue_0_frame_errors",
	"rx_queue_0_length_errors",
	"rx_queue_0_missed_errors",
	"rx_queue_0_over_errors",

	"rx_queue_1_current",
	"tx_queue_1_current",
	"rx_queue_1_dirty",
	"tx_queue_1_dirty",
	"rx_queue_1_packets",
	"tx_queue_1_packets",
	"rx_queue_1_bytes",
	"tx_queue_1_bytes",
	"rx_queue_1_mcast_packets",
	"rx_queue_1_errors",
	"rx_queue_1_crc_errors",
	"rx_queue_1_frame_errors_",
	"rx_queue_1_length_errors",
	"rx_queue_1_missed_errors",
	"rx_queue_1_over_errors",
};

#define RAVB_STATS_LEN	ARRAY_SIZE(ravb_gstrings_stats)

static int ravb_get_sset_count(struct net_device *netdev, int sset)
{
	switch (sset) {
	case ETH_SS_STATS:
		return RAVB_STATS_LEN;
	default:
		return -EOPNOTSUPP;
	}
}

static void ravb_get_ethtool_stats(struct net_device *ndev,
				   struct ethtool_stats *stats, u64 *data)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int i = 0;
	int q;

	/* Device-specific stats */
	for (q = RAVB_BE; q < NUM_RX_QUEUE; q++) {
		struct net_device_stats *stats = &priv->stats[q];

		data[i++] = priv->cur_rx[q];
		data[i++] = priv->cur_tx[q];
		data[i++] = priv->dirty_rx[q];
		data[i++] = priv->dirty_tx[q];
		data[i++] = stats->rx_packets;
		data[i++] = stats->tx_packets;
		data[i++] = stats->rx_bytes;
		data[i++] = stats->tx_bytes;
		data[i++] = stats->multicast;
		data[i++] = stats->rx_errors;
		data[i++] = stats->rx_crc_errors;
		data[i++] = stats->rx_frame_errors;
		data[i++] = stats->rx_length_errors;
		data[i++] = stats->rx_missed_errors;
		data[i++] = stats->rx_over_errors;
	}
}

static void ravb_get_strings(struct net_device *ndev, u32 stringset, u8 *data)
{
	switch (stringset) {
	case ETH_SS_STATS:
		memcpy(data, *ravb_gstrings_stats, sizeof(ravb_gstrings_stats));
		break;
	}
}

static void ravb_get_ringparam(struct net_device *ndev,
			       struct ethtool_ringparam *ring)
{
	struct ravb_private *priv = netdev_priv(ndev);

	ring->rx_max_pending = BE_RX_RING_MAX;
	ring->tx_max_pending = BE_TX_RING_MAX;
	ring->rx_pending = priv->num_rx_ring[RAVB_BE];
	ring->tx_pending = priv->num_tx_ring[RAVB_BE];
}

static int ravb_set_ringparam(struct net_device *ndev,
			      struct ethtool_ringparam *ring)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int error;

	if (ring->tx_pending > BE_TX_RING_MAX ||
	    ring->rx_pending > BE_RX_RING_MAX ||
	    ring->tx_pending < BE_TX_RING_MIN ||
	    ring->rx_pending < BE_RX_RING_MIN)
		return -EINVAL;
	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
		return -EINVAL;

	if (netif_running(ndev)) {
		netif_device_detach(ndev);
		/* Stop PTP Clock driver */
		ravb_ptp_stop(ndev);
		/* Wait for DMA stopping */
		error = ravb_stop_dma(ndev);
		if (error) {
			netdev_err(ndev,
				   "cannot set ringparam! Any AVB processes are still running?\n");
			return error;
		}
		synchronize_irq(ndev->irq);

		/* Free all the skb's in the RX queue and the DMA buffers. */
		ravb_ring_free(ndev, RAVB_BE);
		ravb_ring_free(ndev, RAVB_NC);
	}

	/* Set new parameters */
	priv->num_rx_ring[RAVB_BE] = ring->rx_pending;
	priv->num_tx_ring[RAVB_BE] = ring->tx_pending;

	if (netif_running(ndev)) {
		error = ravb_dmac_init(ndev);
		if (error) {
			netdev_err(ndev,
				   "%s: ravb_dmac_init() failed, error %d\n",
				   __func__, error);
			return error;
		}

		ravb_emac_init(ndev);

		/* Initialise PTP Clock driver */
		ravb_ptp_init(ndev, priv->pdev);

		netif_device_attach(ndev);
	}

	return 0;
}

static int ravb_get_ts_info(struct net_device *ndev,
			    struct ethtool_ts_info *info)
{
	struct ravb_private *priv = netdev_priv(ndev);

	info->so_timestamping =
		SOF_TIMESTAMPING_TX_SOFTWARE |
		SOF_TIMESTAMPING_RX_SOFTWARE |
		SOF_TIMESTAMPING_SOFTWARE |
		SOF_TIMESTAMPING_TX_HARDWARE |
		SOF_TIMESTAMPING_RX_HARDWARE |
		SOF_TIMESTAMPING_RAW_HARDWARE;
	info->tx_types = (1 << HWTSTAMP_TX_OFF) | (1 << HWTSTAMP_TX_ON);
	info->rx_filters =
		(1 << HWTSTAMP_FILTER_NONE) |
		(1 << HWTSTAMP_FILTER_PTP_V2_L2_EVENT) |
		(1 << HWTSTAMP_FILTER_ALL);
	info->phc_index = ptp_clock_index(priv->ptp.clock);

	return 0;
}

static const struct ethtool_ops ravb_ethtool_ops = {
	.get_settings		= ravb_get_settings,
	.set_settings		= ravb_set_settings,
	.nway_reset		= ravb_nway_reset,
	.get_msglevel		= ravb_get_msglevel,
	.set_msglevel		= ravb_set_msglevel,
	.get_link		= ethtool_op_get_link,
	.get_strings		= ravb_get_strings,
	.get_ethtool_stats	= ravb_get_ethtool_stats,
	.get_sset_count		= ravb_get_sset_count,
	.get_ringparam		= ravb_get_ringparam,
	.set_ringparam		= ravb_set_ringparam,
	.get_ts_info		= ravb_get_ts_info,
};

/* Network device open function for Ethernet AVB */
static int ravb_open(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	int error;

	napi_enable(&priv->napi[RAVB_BE]);
	napi_enable(&priv->napi[RAVB_NC]);

	error = request_irq(ndev->irq, ravb_interrupt, IRQF_SHARED, ndev->name,
			    ndev);
	if (error) {
		netdev_err(ndev, "cannot request IRQ\n");
		goto out_napi_off;
	}

	/* Device init */
	error = ravb_dmac_init(ndev);
	if (error)
		goto out_free_irq;
	ravb_emac_init(ndev);

	/* Initialise PTP Clock driver */
	ravb_ptp_init(ndev, priv->pdev);

	netif_tx_start_all_queues(ndev);

	/* PHY control start */
	error = ravb_phy_start(ndev);
	if (error)
		goto out_ptp_stop;

	return 0;

out_ptp_stop:
	/* Stop PTP Clock driver */
	ravb_ptp_stop(ndev);
out_free_irq:
	free_irq(ndev->irq, ndev);
out_napi_off:
	napi_disable(&priv->napi[RAVB_NC]);
	napi_disable(&priv->napi[RAVB_BE]);
	return error;
}

/* Timeout function for Ethernet AVB */
static void ravb_tx_timeout(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);

	netif_err(priv, tx_err, ndev,
		  "transmit timed out, status %08x, resetting...\n",
		  ravb_read(ndev, ISS));

	/* tx_errors count up */
	ndev->stats.tx_errors++;

	schedule_work(&priv->work);
}

static void ravb_tx_timeout_work(struct work_struct *work)
{
	struct ravb_private *priv = container_of(work, struct ravb_private,
						 work);
	struct net_device *ndev = priv->ndev;

	netif_tx_stop_all_queues(ndev);

	/* Stop PTP Clock driver */
	ravb_ptp_stop(ndev);

	/* Wait for DMA stopping */
	ravb_stop_dma(ndev);

	ravb_ring_free(ndev, RAVB_BE);
	ravb_ring_free(ndev, RAVB_NC);

	/* Device init */
	ravb_dmac_init(ndev);
	ravb_emac_init(ndev);

	/* Initialise PTP Clock driver */
	ravb_ptp_init(ndev, priv->pdev);

	netif_tx_start_all_queues(ndev);
}

/* Packet transmit function for Ethernet AVB */
static netdev_tx_t ravb_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct ravb_tstamp_skb *ts_skb = NULL;
	u16 q = skb_get_queue_mapping(skb);
	struct ravb_tx_desc *desc;
	unsigned long flags;
	u32 dma_addr;
	void *buffer;
	u32 entry;

	spin_lock_irqsave(&priv->lock, flags);
	if (priv->cur_tx[q] - priv->dirty_tx[q] >= priv->num_tx_ring[q]) {
		netif_err(priv, tx_queued, ndev,
			  "still transmitting with the full ring!\n");
		netif_stop_subqueue(ndev, q);
		spin_unlock_irqrestore(&priv->lock, flags);
		return NETDEV_TX_BUSY;
	}
	entry = priv->cur_tx[q] % priv->num_tx_ring[q];
	priv->tx_skb[q][entry] = skb;

	if (skb_put_padto(skb, ETH_ZLEN))
		goto drop;

	buffer = PTR_ALIGN(priv->tx_buffers[q][entry], RAVB_ALIGN);
	memcpy(buffer, skb->data, skb->len);
	desc = &priv->tx_ring[q][entry];
	desc->ds_tagl = cpu_to_le16(skb->len);
	dma_addr = dma_map_single(&ndev->dev, buffer, skb->len, DMA_TO_DEVICE);
	if (dma_mapping_error(&ndev->dev, dma_addr))
		goto drop;
	desc->dptr = cpu_to_le32(dma_addr);

	/* TX timestamp required */
	if (q == RAVB_NC) {
		ts_skb = kmalloc(sizeof(*ts_skb), GFP_ATOMIC);
		if (!ts_skb) {
			dma_unmap_single(&ndev->dev, dma_addr, skb->len,
					 DMA_TO_DEVICE);
			goto drop;
		}
		ts_skb->skb = skb;
		ts_skb->tag = priv->ts_skb_tag++;
		priv->ts_skb_tag &= 0x3ff;
		list_add_tail(&ts_skb->list, &priv->ts_skb_list);

		/* TAG and timestamp required flag */
		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
		skb_tx_timestamp(skb);
		desc->tagh_tsr = (ts_skb->tag >> 4) | TX_TSR;
		desc->ds_tagl |= le16_to_cpu(ts_skb->tag << 12);
	}

	/* Descriptor type must be set after all the above writes */
	dma_wmb();
	desc->die_dt = DT_FSINGLE;

	ravb_write(ndev, ravb_read(ndev, TCCR) | (TCCR_TSRQ0 << q), TCCR);

	priv->cur_tx[q]++;
	if (priv->cur_tx[q] - priv->dirty_tx[q] >= priv->num_tx_ring[q] &&
	    !ravb_tx_free(ndev, q))
		netif_stop_subqueue(ndev, q);

exit:
	mmiowb();
	spin_unlock_irqrestore(&priv->lock, flags);
	return NETDEV_TX_OK;

drop:
	dev_kfree_skb_any(skb);
	priv->tx_skb[q][entry] = NULL;
	goto exit;
}

static u16 ravb_select_queue(struct net_device *ndev, struct sk_buff *skb,
			     void *accel_priv, select_queue_fallback_t fallback)
{
	/* If skb needs TX timestamp, it is handled in network control queue */
	return (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) ? RAVB_NC :
							       RAVB_BE;

}

static struct net_device_stats *ravb_get_stats(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct net_device_stats *nstats, *stats0, *stats1;

	nstats = &ndev->stats;
	stats0 = &priv->stats[RAVB_BE];
	stats1 = &priv->stats[RAVB_NC];

	nstats->tx_dropped += ravb_read(ndev, TROCR);
	ravb_write(ndev, 0, TROCR);	/* (write clear) */
	nstats->collisions += ravb_read(ndev, CDCR);
	ravb_write(ndev, 0, CDCR);	/* (write clear) */
	nstats->tx_carrier_errors += ravb_read(ndev, LCCR);
	ravb_write(ndev, 0, LCCR);	/* (write clear) */

	nstats->tx_carrier_errors += ravb_read(ndev, CERCR);
	ravb_write(ndev, 0, CERCR);	/* (write clear) */
	nstats->tx_carrier_errors += ravb_read(ndev, CEECR);
	ravb_write(ndev, 0, CEECR);	/* (write clear) */

	nstats->rx_packets = stats0->rx_packets + stats1->rx_packets;
	nstats->tx_packets = stats0->tx_packets + stats1->tx_packets;
	nstats->rx_bytes = stats0->rx_bytes + stats1->rx_bytes;
	nstats->tx_bytes = stats0->tx_bytes + stats1->tx_bytes;
	nstats->multicast = stats0->multicast + stats1->multicast;
	nstats->rx_errors = stats0->rx_errors + stats1->rx_errors;
	nstats->rx_crc_errors = stats0->rx_crc_errors + stats1->rx_crc_errors;
	nstats->rx_frame_errors =
		stats0->rx_frame_errors + stats1->rx_frame_errors;
	nstats->rx_length_errors =
		stats0->rx_length_errors + stats1->rx_length_errors;
	nstats->rx_missed_errors =
		stats0->rx_missed_errors + stats1->rx_missed_errors;
	nstats->rx_over_errors =
		stats0->rx_over_errors + stats1->rx_over_errors;

	return nstats;
}

/* Update promiscuous bit */
static void ravb_set_rx_mode(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	unsigned long flags;
	u32 ecmr;

	spin_lock_irqsave(&priv->lock, flags);
	ecmr = ravb_read(ndev, ECMR);
	if (ndev->flags & IFF_PROMISC)
		ecmr |=  ECMR_PRM;
	else
		ecmr &= ~ECMR_PRM;
	ravb_write(ndev, ecmr, ECMR);
	mmiowb();
	spin_unlock_irqrestore(&priv->lock, flags);
}

/* Device close function for Ethernet AVB */
static int ravb_close(struct net_device *ndev)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct ravb_tstamp_skb *ts_skb, *ts_skb2;

	netif_tx_stop_all_queues(ndev);

	/* Disable interrupts by clearing the interrupt masks. */
	ravb_write(ndev, 0, RIC0);
	ravb_write(ndev, 0, RIC1);
	ravb_write(ndev, 0, RIC2);
	ravb_write(ndev, 0, TIC);

	/* Stop PTP Clock driver */
	ravb_ptp_stop(ndev);

	/* Set the config mode to stop the AVB-DMAC's processes */
	if (ravb_stop_dma(ndev) < 0)
		netdev_err(ndev,
			   "device will be stopped after h/w processes are done.\n");

	/* Clear the timestamp list */
	list_for_each_entry_safe(ts_skb, ts_skb2, &priv->ts_skb_list, list) {
		list_del(&ts_skb->list);
		kfree(ts_skb);
	}

	/* PHY disconnect */
	if (priv->phydev) {
		phy_stop(priv->phydev);
		phy_disconnect(priv->phydev);
		priv->phydev = NULL;
	}

	free_irq(ndev->irq, ndev);

	napi_disable(&priv->napi[RAVB_NC]);
	napi_disable(&priv->napi[RAVB_BE]);

	/* Free all the skb's in the RX queue and the DMA buffers. */
	ravb_ring_free(ndev, RAVB_BE);
	ravb_ring_free(ndev, RAVB_NC);

	return 0;
}

static int ravb_hwtstamp_get(struct net_device *ndev, struct ifreq *req)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct hwtstamp_config config;

	config.flags = 0;
	config.tx_type = priv->tstamp_tx_ctrl ? HWTSTAMP_TX_ON :
						HWTSTAMP_TX_OFF;
	if (priv->tstamp_rx_ctrl & RAVB_RXTSTAMP_TYPE_V2_L2_EVENT)
		config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L2_EVENT;
	else if (priv->tstamp_rx_ctrl & RAVB_RXTSTAMP_TYPE_ALL)
		config.rx_filter = HWTSTAMP_FILTER_ALL;
	else
		config.rx_filter = HWTSTAMP_FILTER_NONE;

	return copy_to_user(req->ifr_data, &config, sizeof(config)) ?
		-EFAULT : 0;
}

/* Control hardware time stamping */
static int ravb_hwtstamp_set(struct net_device *ndev, struct ifreq *req)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct hwtstamp_config config;
	u32 tstamp_rx_ctrl = RAVB_RXTSTAMP_ENABLED;
	u32 tstamp_tx_ctrl;

	if (copy_from_user(&config, req->ifr_data, sizeof(config)))
		return -EFAULT;

	/* Reserved for future extensions */
	if (config.flags)
		return -EINVAL;

	switch (config.tx_type) {
	case HWTSTAMP_TX_OFF:
		tstamp_tx_ctrl = 0;
		break;
	case HWTSTAMP_TX_ON:
		tstamp_tx_ctrl = RAVB_TXTSTAMP_ENABLED;
		break;
	default:
		return -ERANGE;
	}

	switch (config.rx_filter) {
	case HWTSTAMP_FILTER_NONE:
		tstamp_rx_ctrl = 0;
		break;
	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
		tstamp_rx_ctrl |= RAVB_RXTSTAMP_TYPE_V2_L2_EVENT;
		break;
	default:
		config.rx_filter = HWTSTAMP_FILTER_ALL;
		tstamp_rx_ctrl |= RAVB_RXTSTAMP_TYPE_ALL;
	}

	priv->tstamp_tx_ctrl = tstamp_tx_ctrl;
	priv->tstamp_rx_ctrl = tstamp_rx_ctrl;

	return copy_to_user(req->ifr_data, &config, sizeof(config)) ?
		-EFAULT : 0;
}

/* ioctl to device function */
static int ravb_do_ioctl(struct net_device *ndev, struct ifreq *req, int cmd)
{
	struct ravb_private *priv = netdev_priv(ndev);
	struct phy_device *phydev = priv->phydev;

	if (!netif_running(ndev))
		return -EINVAL;

	if (!phydev)
		return -ENODEV;

	switch (cmd) {
	case SIOCGHWTSTAMP:
		return ravb_hwtstamp_get(ndev, req);
	case SIOCSHWTSTAMP:
		return ravb_hwtstamp_set(ndev, req);
	}

	return phy_mii_ioctl(phydev, req, cmd);
}

static const struct net_device_ops ravb_netdev_ops = {
	.ndo_open		= ravb_open,
	.ndo_stop		= ravb_close,
	.ndo_start_xmit		= ravb_start_xmit,
	.ndo_select_queue	= ravb_select_queue,
	.ndo_get_stats		= ravb_get_stats,
	.ndo_set_rx_mode	= ravb_set_rx_mode,
	.ndo_tx_timeout		= ravb_tx_timeout,
	.ndo_do_ioctl		= ravb_do_ioctl,
	.ndo_validate_addr	= eth_validate_addr,
	.ndo_set_mac_address	= eth_mac_addr,
	.ndo_change_mtu		= eth_change_mtu,
};

/* MDIO bus init function */
static int ravb_mdio_init(struct ravb_private *priv)
{
	struct platform_device *pdev = priv->pdev;
	struct device *dev = &pdev->dev;
	int error;

	/* Bitbang init */
	priv->mdiobb.ops = &bb_ops;

	/* MII controller setting */
	priv->mii_bus = alloc_mdio_bitbang(&priv->mdiobb);
	if (!priv->mii_bus)
		return -ENOMEM;

	/* Hook up MII support for ethtool */
	priv->mii_bus->name = "ravb_mii";
	priv->mii_bus->parent = dev;
	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
		 pdev->name, pdev->id);

	/* Register MDIO bus */
	error = of_mdiobus_register(priv->mii_bus, dev->of_node);
	if (error)
		goto out_free_bus;

	return 0;

out_free_bus:
	free_mdio_bitbang(priv->mii_bus);
	return error;
}

/* MDIO bus release function */
static int ravb_mdio_release(struct ravb_private *priv)
{
	/* Unregister mdio bus */
	mdiobus_unregister(priv->mii_bus);

	/* Free bitbang info */
	free_mdio_bitbang(priv->mii_bus);

	return 0;
}

static int ravb_probe(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct ravb_private *priv;
	struct net_device *ndev;
	int error, irq, q;
	struct resource *res;

	if (!np) {
		dev_err(&pdev->dev,
			"this driver is required to be instantiated from device tree\n");
		return -EINVAL;
	}

	/* Get base address */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(&pdev->dev, "invalid resource\n");
		return -EINVAL;
	}

	ndev = alloc_etherdev_mqs(sizeof(struct ravb_private),
				  NUM_TX_QUEUE, NUM_RX_QUEUE);
	if (!ndev)
		return -ENOMEM;

	pm_runtime_enable(&pdev->dev);
	pm_runtime_get_sync(&pdev->dev);

	/* The Ether-specific entries in the device structure. */
	ndev->base_addr = res->start;
	ndev->dma = -1;
	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		error = -ENODEV;
		goto out_release;
	}
	ndev->irq = irq;

	SET_NETDEV_DEV(ndev, &pdev->dev);

	priv = netdev_priv(ndev);
	priv->ndev = ndev;
	priv->pdev = pdev;
	priv->num_tx_ring[RAVB_BE] = BE_TX_RING_SIZE;
	priv->num_rx_ring[RAVB_BE] = BE_RX_RING_SIZE;
	priv->num_tx_ring[RAVB_NC] = NC_TX_RING_SIZE;
	priv->num_rx_ring[RAVB_NC] = NC_RX_RING_SIZE;
	priv->addr = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(priv->addr)) {
		error = PTR_ERR(priv->addr);
		goto out_release;
	}

	spin_lock_init(&priv->lock);
	INIT_WORK(&priv->work, ravb_tx_timeout_work);

	priv->phy_interface = of_get_phy_mode(np);

	priv->no_avb_link = of_property_read_bool(np, "renesas,no-ether-link");
	priv->avb_link_active_low =
		of_property_read_bool(np, "renesas,ether-link-active-low");

	/* Set function */
	ndev->netdev_ops = &ravb_netdev_ops;
	ndev->ethtool_ops = &ravb_ethtool_ops;

	/* Set AVB config mode */
	ravb_write(ndev, (ravb_read(ndev, CCC) & ~CCC_OPC) | CCC_OPC_CONFIG,
		   CCC);

	/* Set CSEL value */
	ravb_write(ndev, (ravb_read(ndev, CCC) & ~CCC_CSEL) | CCC_CSEL_HPB,
		   CCC);

	/* Set GTI value */
	ravb_write(ndev, ((1000 << 20) / 130) & GTI_TIV, GTI);

	/* Request GTI loading */
	ravb_write(ndev, ravb_read(ndev, GCCR) | GCCR_LTI, GCCR);

	/* Allocate descriptor base address table */
	priv->desc_bat_size = sizeof(struct ravb_desc) * DBAT_ENTRY_NUM;
	priv->desc_bat = dma_alloc_coherent(NULL, priv->desc_bat_size,
					    &priv->desc_bat_dma, GFP_KERNEL);
	if (!priv->desc_bat) {
		dev_err(&ndev->dev,
			"Cannot allocate desc base address table (size %d bytes)\n",
			priv->desc_bat_size);
		error = -ENOMEM;
		goto out_release;
	}
	for (q = RAVB_BE; q < DBAT_ENTRY_NUM; q++)
		priv->desc_bat[q].die_dt = DT_EOS;
	ravb_write(ndev, priv->desc_bat_dma, DBAT);

	/* Initialise HW timestamp list */
	INIT_LIST_HEAD(&priv->ts_skb_list);

	/* Debug message level */
	priv->msg_enable = RAVB_DEF_MSG_ENABLE;

	/* Read and set MAC address */
	ravb_read_mac_address(ndev, of_get_mac_address(np));
	if (!is_valid_ether_addr(ndev->dev_addr)) {
		dev_warn(&pdev->dev,
			 "no valid MAC address supplied, using a random one\n");
		eth_hw_addr_random(ndev);
	}

	/* MDIO bus init */
	error = ravb_mdio_init(priv);
	if (error) {
		dev_err(&ndev->dev, "failed to initialize MDIO\n");
		goto out_dma_free;
	}

	netif_napi_add(ndev, &priv->napi[RAVB_BE], ravb_poll, 64);
	netif_napi_add(ndev, &priv->napi[RAVB_NC], ravb_poll, 64);

	/* Network device register */
	error = register_netdev(ndev);
	if (error)
		goto out_napi_del;

	/* Print device information */
	netdev_info(ndev, "Base address at %#x, %pM, IRQ %d.\n",
		    (u32)ndev->base_addr, ndev->dev_addr, ndev->irq);

	platform_set_drvdata(pdev, ndev);

	return 0;

out_napi_del:
	netif_napi_del(&priv->napi[RAVB_NC]);
	netif_napi_del(&priv->napi[RAVB_BE]);
	ravb_mdio_release(priv);
out_dma_free:
	dma_free_coherent(NULL, priv->desc_bat_size, priv->desc_bat,
			  priv->desc_bat_dma);
out_release:
	if (ndev)
		free_netdev(ndev);

	pm_runtime_put(&pdev->dev);
	pm_runtime_disable(&pdev->dev);
	return error;
}

static int ravb_remove(struct platform_device *pdev)
{
	struct net_device *ndev = platform_get_drvdata(pdev);
	struct ravb_private *priv = netdev_priv(ndev);

	dma_free_coherent(NULL, priv->desc_bat_size, priv->desc_bat,
			  priv->desc_bat_dma);
	/* Set reset mode */
	ravb_write(ndev, CCC_OPC_RESET, CCC);
	pm_runtime_put_sync(&pdev->dev);
	unregister_netdev(ndev);
	netif_napi_del(&priv->napi[RAVB_NC]);
	netif_napi_del(&priv->napi[RAVB_BE]);
	ravb_mdio_release(priv);
	pm_runtime_disable(&pdev->dev);
	free_netdev(ndev);
	platform_set_drvdata(pdev, NULL);

	return 0;
}

#ifdef CONFIG_PM
static int ravb_runtime_nop(struct device *dev)
{
	/* Runtime PM callback shared between ->runtime_suspend()
	 * and ->runtime_resume(). Simply returns success.
	 *
	 * This driver re-initializes all registers after
	 * pm_runtime_get_sync() anyway so there is no need
	 * to save and restore registers here.
	 */
	return 0;
}

static const struct dev_pm_ops ravb_dev_pm_ops = {
	.runtime_suspend = ravb_runtime_nop,
	.runtime_resume = ravb_runtime_nop,
};

#define RAVB_PM_OPS (&ravb_dev_pm_ops)
#else
#define RAVB_PM_OPS NULL
#endif

static const struct of_device_id ravb_match_table[] = {
	{ .compatible = "renesas,etheravb-r8a7790" },
	{ .compatible = "renesas,etheravb-r8a7794" },
	{ }
};
MODULE_DEVICE_TABLE(of, ravb_match_table);

static struct platform_driver ravb_driver = {
	.probe		= ravb_probe,
	.remove		= ravb_remove,
	.driver = {
		.name	= "ravb",
		.pm	= RAVB_PM_OPS,
		.of_match_table = ravb_match_table,
	},
};

module_platform_driver(ravb_driver);

MODULE_AUTHOR("Mitsuhiro Kimura, Masaru Nagai");
MODULE_DESCRIPTION("Renesas Ethernet AVB driver");
MODULE_LICENSE("GPL v2");