// SPDX-License-Identifier: GPL-2.0
/* Renesas Ethernet AVB device driver
 *
 * Copyright (C) 2014-2019 Renesas Electronics Corporation
 * Copyright (C) 2015 Renesas Solutions Corp.
 * Copyright (C) 2015-2016 Cogent Embedded, Inc. <source@cogentembedded.com>
 *
 * Based on the SuperH Ethernet driver
 */

#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 <linux/sys_soc.h>
#include <linux/reset.h>

#include <asm/div64.h>

#include "ravb.h"

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

static const char *ravb_rx_irqs[NUM_RX_QUEUE] = {
        "ch0", /* RAVB_BE */
        "ch1", /* RAVB_NC */
};

static const char *ravb_tx_irqs[NUM_TX_QUEUE] = {
        "ch18", /* RAVB_BE */
        "ch19", /* RAVB_NC */
};

void ravb_modify(struct net_device *ndev, enum ravb_reg reg, u32 clear,
                 u32 set)
{
        ravb_write(ndev, (ravb_read(ndev, reg) & ~clear) | set, reg);
}

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_modify(ndev, CCC, CCC_OPC, CCC_OPC_CONFIG);
        /* 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_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;
        }
}

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 device_node *np,
                                  struct net_device *ndev)
{
        int ret;

        ret = of_get_mac_address(np, ndev->dev_addr);
        if (ret) {
                u32 mahr = ravb_read(ndev, MAHR);
                u32 malr = ravb_read(ndev, MALR);

                ndev->dev_addr[0] = (mahr >> 24) & 0xFF;
                ndev->dev_addr[1] = (mahr >> 16) & 0xFF;
                ndev->dev_addr[2] = (mahr >>  8) & 0xFF;
                ndev->dev_addr[3] = (mahr >>  0) & 0xFF;
                ndev->dev_addr[4] = (malr >>  8) & 0xFF;
                ndev->dev_addr[5] = (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);

        ravb_modify(priv->ndev, PIR, mask, set ? mask : 0);
}

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

        for (; priv->cur_tx[q] - priv->dirty_tx[q] > 0; priv->dirty_tx[q]++) {
                bool txed;

                entry = priv->dirty_tx[q] % (priv->num_tx_ring[q] *
                                             num_tx_desc);
                desc = &priv->tx_ring[q][entry];
                txed = desc->die_dt == DT_FEMPTY;
                if (free_txed_only && !txed)
                        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 / num_tx_desc]) {
                        dma_unmap_single(ndev->dev.parent, le32_to_cpu(desc->dptr),
                                         size, DMA_TO_DEVICE);
                        /* Last packet descriptor? */
                        if (entry % num_tx_desc == num_tx_desc - 1) {
                                entry /= num_tx_desc;
                                dev_kfree_skb_any(priv->tx_skb[q][entry]);
                                priv->tx_skb[q][entry] = NULL;
                                if (txed)
                                        stats->tx_packets++;
                        }
                        free_num++;
                }
                if (txed)
                        stats->tx_bytes += size;
                desc->die_dt = DT_EEMPTY;
        }
        return free_num;
}

static void ravb_rx_ring_free(struct net_device *ndev, int q)
{
        struct ravb_private *priv = netdev_priv(ndev);
        unsigned int ring_size;
        unsigned int i;

        if (!priv->rx_ring[q])
                return;

        for (i = 0; i < priv->num_rx_ring[q]; i++) {
                struct ravb_ex_rx_desc *desc = &priv->rx_ring[q][i];

                if (!dma_mapping_error(ndev->dev.parent,
                                       le32_to_cpu(desc->dptr)))
                        dma_unmap_single(ndev->dev.parent,
                                         le32_to_cpu(desc->dptr),
                                         RX_BUF_SZ,
                                         DMA_FROM_DEVICE);
        }
        ring_size = sizeof(struct ravb_ex_rx_desc) *
                    (priv->num_rx_ring[q] + 1);
        dma_free_coherent(ndev->dev.parent, ring_size, priv->rx_ring[q],
                          priv->rx_desc_dma[q]);
        priv->rx_ring[q] = NULL;
}

/* 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);
        const struct ravb_hw_info *info = priv->info;
        unsigned int num_tx_desc = priv->num_tx_desc;
        unsigned int ring_size;
        unsigned int i;

        info->rx_ring_free(ndev, q);

        if (priv->tx_ring[q]) {
                ravb_tx_free(ndev, q, false);

                ring_size = sizeof(struct ravb_tx_desc) *
                            (priv->num_tx_ring[q] * num_tx_desc + 1);
                dma_free_coherent(ndev->dev.parent, ring_size, priv->tx_ring[q],
                                  priv->tx_desc_dma[q]);
                priv->tx_ring[q] = NULL;
        }

        /* 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 aligned TX buffers */
        kfree(priv->tx_align[q]);
        priv->tx_align[q] = NULL;

        /* Free TX skb ringbuffer.
         * SKBs are freed by ravb_tx_free() call above.
         */
        kfree(priv->tx_skb[q]);
        priv->tx_skb[q] = NULL;
}

static void ravb_rx_ring_format(struct net_device *ndev, int q)
{
        struct ravb_private *priv = netdev_priv(ndev);
        struct ravb_ex_rx_desc *rx_desc;
        unsigned int rx_ring_size = sizeof(*rx_desc) * priv->num_rx_ring[q];
        dma_addr_t dma_addr;
        unsigned int i;

        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];
                rx_desc->ds_cc = cpu_to_le16(RX_BUF_SZ);
                dma_addr = dma_map_single(ndev->dev.parent, priv->rx_skb[q][i]->data,
                                          RX_BUF_SZ,
                                          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.parent, 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 */
}

/* 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);
        const struct ravb_hw_info *info = priv->info;
        unsigned int num_tx_desc = priv->num_tx_desc;
        struct ravb_tx_desc *tx_desc;
        struct ravb_desc *desc;
        unsigned int tx_ring_size = sizeof(*tx_desc) * priv->num_tx_ring[q] *
                                    num_tx_desc;
        unsigned int i;

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

        info->rx_ring_format(ndev, q);

        memset(priv->tx_ring[q], 0, tx_ring_size);
        /* Build TX ring buffer */
        for (i = 0, tx_desc = priv->tx_ring[q]; i < priv->num_tx_ring[q];
             i++, tx_desc++) {
                tx_desc->die_dt = DT_EEMPTY;
                if (num_tx_desc > 1) {
                        tx_desc++;
                        tx_desc->die_dt = DT_EEMPTY;
                }
        }
        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]);
}

static void *ravb_alloc_rx_desc(struct net_device *ndev, int q)
{
        struct ravb_private *priv = netdev_priv(ndev);
        unsigned int ring_size;

        ring_size = sizeof(struct ravb_ex_rx_desc) * (priv->num_rx_ring[q] + 1);

        priv->rx_ring[q] = dma_alloc_coherent(ndev->dev.parent, ring_size,
                                              &priv->rx_desc_dma[q],
                                              GFP_KERNEL);
        return priv->rx_ring[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);
        const struct ravb_hw_info *info = priv->info;
        unsigned int num_tx_desc = priv->num_tx_desc;
        unsigned int ring_size;
        struct sk_buff *skb;
        unsigned 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, info->max_rx_len);
                if (!skb)
                        goto error;
                ravb_set_buffer_align(skb);
                priv->rx_skb[q][i] = skb;
        }

        if (num_tx_desc > 1) {
                /* Allocate rings for the aligned buffers */
                priv->tx_align[q] = kmalloc(DPTR_ALIGN * priv->num_tx_ring[q] +
                                            DPTR_ALIGN - 1, GFP_KERNEL);
                if (!priv->tx_align[q])
                        goto error;
        }

        /* Allocate all RX descriptors. */
        if (!info->alloc_rx_desc(ndev, q))
                goto error;

        priv->dirty_rx[q] = 0;

        /* Allocate all TX descriptors. */
        ring_size = sizeof(struct ravb_tx_desc) *
                    (priv->num_tx_ring[q] * num_tx_desc + 1);
        priv->tx_ring[q] = dma_alloc_coherent(ndev->dev.parent, 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;
}

static void ravb_rcar_emac_init(struct net_device *ndev)
{
        /* Receive frame limit set register */
        ravb_write(ndev, ndev->mtu + ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN, RFLR);

        /* EMAC Mode: PAUSE prohibition; Duplex; RX Checksum; TX; RX */
        ravb_write(ndev, ECMR_ZPF | ECMR_DM |
                   (ndev->features & NETIF_F_RXCSUM ? ECMR_RCSC : 0) |
                   ECMR_TE | ECMR_RE, 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);

        /* 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);
}

/* E-MAC init function */
static void ravb_emac_init(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;

        info->emac_init(ndev);
}

static void ravb_rcar_dmac_init(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;

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

        /* Set FIFO size */
        ravb_write(ndev, TGC_TQP_AVBMODE1 | 0x00112200, TGC);

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

        /* Interrupt init: */
        if (info->multi_irqs) {
                /* Clear DIL.DPLx */
                ravb_write(ndev, 0, DIL);
                /* Set queue specific interrupt */
                ravb_write(ndev, CIE_CRIE | CIE_CTIE | CIE_CL0M, CIE);
        }
        /* Frame receive */
        ravb_write(ndev, RIC0_FRE0 | RIC0_FRE1, RIC0);
        /* Disable FIFO full warning */
        ravb_write(ndev, 0, 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);
}

/* Device init function for Ethernet AVB */
static int ravb_dmac_init(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;
        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);

        info->dmac_init(ndev);

        /* Setting the control will start the AVB-DMAC process. */
        ravb_modify(ndev, CCC, CCC_OPC, CCC_OPC_OPERATION);

        return 0;
}

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);
                                dev_consume_skb_any(skb);
                                break;
                        } else {
                                dev_kfree_skb_any(skb);
                        }
                }
                ravb_modify(ndev, TCCR, TCCR_TFR, TCCR_TFR);
        }
}

static void ravb_rx_csum(struct sk_buff *skb)
{
        u8 *hw_csum;

        /* The hardware checksum is contained in sizeof(__sum16) (2) bytes
         * appended to packet data
         */
        if (unlikely(skb->len < sizeof(__sum16)))
                return;
        hw_csum = skb_tail_pointer(skb) - sizeof(__sum16);
        skb->csum = csum_unfold((__force __sum16)get_unaligned_le16(hw_csum));
        skb->ip_summed = CHECKSUM_COMPLETE;
        skb_trim(skb, skb->len - sizeof(__sum16));
}

static bool ravb_rcar_rx(struct net_device *ndev, int *quota, int q)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;
        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;
        u8  desc_status;
        u16 pkt_len;
        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.parent, le32_to_cpu(desc->dptr),
                                         RX_BUF_SZ,
                                         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);
                        if (ndev->features & NETIF_F_RXCSUM)
                                ravb_rx_csum(skb);
                        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];
                desc->ds_cc = cpu_to_le16(RX_BUF_SZ);

                if (!priv->rx_skb[q][entry]) {
                        skb = netdev_alloc_skb(ndev, info->max_rx_len);
                        if (!skb)
                                break;  /* Better luck next round. */
                        ravb_set_buffer_align(skb);
                        dma_addr = dma_map_single(ndev->dev.parent, 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.parent, 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;
}

/* 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);
        const struct ravb_hw_info *info = priv->info;

        return info->receive(ndev, quota, q);
}

static void ravb_rcv_snd_disable(struct net_device *ndev)
{
        /* Disable TX and RX */
        ravb_modify(ndev, ECMR, ECMR_RE | ECMR_TE, 0);
}

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

/* 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_unlocked(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_MPD)
                pm_wakeup_event(&priv->pdev->dev, 0);
        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);
                }
        }
}

static irqreturn_t ravb_emac_interrupt(int irq, void *dev_id)
{
        struct net_device *ndev = dev_id;
        struct ravb_private *priv = netdev_priv(ndev);

        spin_lock(&priv->lock);
        ravb_emac_interrupt_unlocked(ndev);
        spin_unlock(&priv->lock);
        return IRQ_HANDLED;
}

/* 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_RESERVED), EIS);
        if (eis & EIS_QFS) {
                ris2 = ravb_read(ndev, RIS2);
                ravb_write(ndev, ~(RIS2_QFF0 | RIS2_RFFF | RIS2_RESERVED),
                           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 bool ravb_queue_interrupt(struct net_device *ndev, int q)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;
        u32 ris0 = ravb_read(ndev, RIS0);
        u32 ric0 = ravb_read(ndev, RIC0);
        u32 tis  = ravb_read(ndev, TIS);
        u32 tic  = ravb_read(ndev, TIC);

        if (((ris0 & ric0) & BIT(q)) || ((tis  & tic)  & BIT(q))) {
                if (napi_schedule_prep(&priv->napi[q])) {
                        /* Mask RX and TX interrupts */
                        if (!info->multi_irqs) {
                                ravb_write(ndev, ric0 & ~BIT(q), RIC0);
                                ravb_write(ndev, tic & ~BIT(q), TIC);
                        } else {
                                ravb_write(ndev, BIT(q), RID0);
                                ravb_write(ndev, BIT(q), TID);
                        }
                        __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);
                }
                return true;
        }
        return false;
}

static bool ravb_timestamp_interrupt(struct net_device *ndev)
{
        u32 tis = ravb_read(ndev, TIS);

        if (tis & TIS_TFUF) {
                ravb_write(ndev, ~(TIS_TFUF | TIS_RESERVED), TIS);
                ravb_get_tx_tstamp(ndev);
                return true;
        }
        return false;
}

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)) {
                int q;

                /* Timestamp updated */
                if (ravb_timestamp_interrupt(ndev))
                        result = IRQ_HANDLED;

                /* Network control and best effort queue RX/TX */
                for (q = RAVB_NC; q >= RAVB_BE; q--) {
                        if (ravb_queue_interrupt(ndev, q))
                                result = IRQ_HANDLED;
                }
        }

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

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

        /* gPTP interrupt status summary */
        if (iss & ISS_CGIS) {
                ravb_ptp_interrupt(ndev);
                result = IRQ_HANDLED;
        }

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

/* Timestamp/Error/gPTP interrupt handler */
static irqreturn_t ravb_multi_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);

        /* Timestamp updated */
        if ((iss & ISS_TFUS) && ravb_timestamp_interrupt(ndev))
                result = IRQ_HANDLED;

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

        /* gPTP interrupt status summary */
        if (iss & ISS_CGIS) {
                ravb_ptp_interrupt(ndev);
                result = IRQ_HANDLED;
        }

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

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

        spin_lock(&priv->lock);

        /* Network control/Best effort queue RX/TX */
        if (ravb_queue_interrupt(ndev, q))
                result = IRQ_HANDLED;

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

static irqreturn_t ravb_be_interrupt(int irq, void *dev_id)
{
        return ravb_dma_interrupt(irq, dev_id, RAVB_BE);
}

static irqreturn_t ravb_nc_interrupt(int irq, void *dev_id)
{
        return ravb_dma_interrupt(irq, dev_id, RAVB_NC);
}

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

        /* Processing RX Descriptor Ring */
        /* Clear RX interrupt */
        ravb_write(ndev, ~(mask | RIS0_RESERVED), RIS0);
        if (ravb_rx(ndev, &quota, q))
                goto out;

        /* Processing TX Descriptor Ring */
        spin_lock_irqsave(&priv->lock, flags);
        /* Clear TX interrupt */
        ravb_write(ndev, ~(mask | TIS_RESERVED), TIS);
        ravb_tx_free(ndev, q, true);
        netif_wake_subqueue(ndev, q);
        spin_unlock_irqrestore(&priv->lock, flags);

        napi_complete(napi);

        /* Re-enable RX/TX interrupts */
        spin_lock_irqsave(&priv->lock, flags);
        if (!info->multi_irqs) {
                ravb_modify(ndev, RIC0, mask, mask);
                ravb_modify(ndev, TIC,  mask, mask);
        } else {
                ravb_write(ndev, mask, RIE0);
                ravb_write(ndev, mask, TIE);
        }
        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;
        if (priv->rx_fifo_errors != ndev->stats.rx_fifo_errors)
                ndev->stats.rx_fifo_errors = priv->rx_fifo_errors;
out:
        return budget - quota;
}

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

        spin_lock_irqsave(&priv->lock, flags);

        /* Disable TX and RX right over here, if E-MAC change is ignored */
        if (priv->no_avb_link)
                ravb_rcv_snd_disable(ndev);

        if (phydev->link) {
                if (phydev->speed != priv->speed) {
                        new_state = true;
                        priv->speed = phydev->speed;
                        info->set_rate(ndev);
                }
                if (!priv->link) {
                        ravb_modify(ndev, ECMR, ECMR_TXF, 0);
                        new_state = true;
                        priv->link = phydev->link;
                }
        } else if (priv->link) {
                new_state = true;
                priv->link = 0;
                priv->speed = 0;
        }

        /* Enable TX and RX right over here, if E-MAC change is ignored */
        if (priv->no_avb_link && phydev->link)
                ravb_rcv_snd_enable(ndev);

        spin_unlock_irqrestore(&priv->lock, flags);

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

static const struct soc_device_attribute r8a7795es10[] = {
        { .soc_id = "r8a7795", .revision = "ES1.0", },
        { /* sentinel */ }
};

/* 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;
        phy_interface_t iface;
        int err;

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

        /* Try connecting to PHY */
        pn = of_parse_phandle(np, "phy-handle", 0);
        if (!pn) {
                /* In the case of a fixed PHY, the DT node associated
                 * to the PHY is the Ethernet MAC DT node.
                 */
                if (of_phy_is_fixed_link(np)) {
                        err = of_phy_register_fixed_link(np);
                        if (err)
                                return err;
                }
                pn = of_node_get(np);
        }

        iface = priv->rgmii_override ? PHY_INTERFACE_MODE_RGMII
                                     : priv->phy_interface;
        phydev = of_phy_connect(ndev, pn, ravb_adjust_link, 0, iface);
        of_node_put(pn);
        if (!phydev) {
                netdev_err(ndev, "failed to connect PHY\n");
                err = -ENOENT;
                goto err_deregister_fixed_link;
        }

        /* This driver only support 10/100Mbit speeds on R-Car H3 ES1.0
         * at this time.
         */
        if (soc_device_match(r8a7795es10)) {
                err = phy_set_max_speed(phydev, SPEED_100);
                if (err) {
                        netdev_err(ndev, "failed to limit PHY to 100Mbit/s\n");
                        goto err_phy_disconnect;
                }

                netdev_info(ndev, "limited PHY to 100Mbit/s\n");
        }

        /* 10BASE, Pause and Asym Pause is not supported */
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Full_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_Pause_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_Asym_Pause_BIT);

        /* Half Duplex is not supported */
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);

        phy_attached_info(phydev);

        return 0;

err_phy_disconnect:
        phy_disconnect(phydev);
err_deregister_fixed_link:
        if (of_phy_is_fixed_link(np))
                of_phy_deregister_fixed_link(np);

        return err;
}

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

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

        phy_start(ndev->phydev);

        return 0;
}

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",
};

static int ravb_get_sset_count(struct net_device *netdev, int sset)
{
        struct ravb_private *priv = netdev_priv(netdev);
        const struct ravb_hw_info *info = priv->info;

        switch (sset) {
        case ETH_SS_STATS:
                return info->stats_len;
        default:
                return -EOPNOTSUPP;
        }
}

static void ravb_get_ethtool_stats(struct net_device *ndev,
                                   struct ethtool_stats *estats, 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)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;

        switch (stringset) {
        case ETH_SS_STATS:
                memcpy(data, info->gstrings_stats, info->gstrings_size);
                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);
        const struct ravb_hw_info *info = priv->info;
        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 */
                if (info->no_ptp_cfg_active)
                        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 */
                if (info->no_ptp_cfg_active)
                        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 void ravb_get_wol(struct net_device *ndev, struct ethtool_wolinfo *wol)
{
        struct ravb_private *priv = netdev_priv(ndev);

        wol->supported = WAKE_MAGIC;
        wol->wolopts = priv->wol_enabled ? WAKE_MAGIC : 0;
}

static int ravb_set_wol(struct net_device *ndev, struct ethtool_wolinfo *wol)
{
        struct ravb_private *priv = netdev_priv(ndev);

        if (wol->wolopts & ~WAKE_MAGIC)
                return -EOPNOTSUPP;

        priv->wol_enabled = !!(wol->wolopts & WAKE_MAGIC);

        device_set_wakeup_enable(&priv->pdev->dev, priv->wol_enabled);

        return 0;
}

static const struct ethtool_ops ravb_ethtool_ops = {
        .nway_reset             = phy_ethtool_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,
        .get_link_ksettings     = phy_ethtool_get_link_ksettings,
        .set_link_ksettings     = phy_ethtool_set_link_ksettings,
        .get_wol                = ravb_get_wol,
        .set_wol                = ravb_set_wol,
};

static inline int ravb_hook_irq(unsigned int irq, irq_handler_t handler,
                                struct net_device *ndev, struct device *dev,
                                const char *ch)
{
        char *name;
        int error;

        name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s", ndev->name, ch);
        if (!name)
                return -ENOMEM;
        error = request_irq(irq, handler, 0, name, ndev);
        if (error)
                netdev_err(ndev, "cannot request IRQ %s\n", name);

        return error;
}

/* Network device open function for Ethernet AVB */
static int ravb_open(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;
        struct platform_device *pdev = priv->pdev;
        struct device *dev = &pdev->dev;
        int error;

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

        if (!info->multi_irqs) {
                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;
                }
        } else {
                error = ravb_hook_irq(ndev->irq, ravb_multi_interrupt, ndev,
                                      dev, "ch22:multi");
                if (error)
                        goto out_napi_off;
                error = ravb_hook_irq(priv->emac_irq, ravb_emac_interrupt, ndev,
                                      dev, "ch24:emac");
                if (error)
                        goto out_free_irq;
                error = ravb_hook_irq(priv->rx_irqs[RAVB_BE], ravb_be_interrupt,
                                      ndev, dev, "ch0:rx_be");
                if (error)
                        goto out_free_irq_emac;
                error = ravb_hook_irq(priv->tx_irqs[RAVB_BE], ravb_be_interrupt,
                                      ndev, dev, "ch18:tx_be");
                if (error)
                        goto out_free_irq_be_rx;
                error = ravb_hook_irq(priv->rx_irqs[RAVB_NC], ravb_nc_interrupt,
                                      ndev, dev, "ch1:rx_nc");
                if (error)
                        goto out_free_irq_be_tx;
                error = ravb_hook_irq(priv->tx_irqs[RAVB_NC], ravb_nc_interrupt,
                                      ndev, dev, "ch19:tx_nc");
                if (error)
                        goto out_free_irq_nc_rx;
        }

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

        /* Initialise PTP Clock driver */
        if (info->no_ptp_cfg_active)
                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 */
        if (info->no_ptp_cfg_active)
                ravb_ptp_stop(ndev);
out_free_irq_nc_tx:
        if (!info->multi_irqs)
                goto out_free_irq;
        free_irq(priv->tx_irqs[RAVB_NC], ndev);
out_free_irq_nc_rx:
        free_irq(priv->rx_irqs[RAVB_NC], ndev);
out_free_irq_be_tx:
        free_irq(priv->tx_irqs[RAVB_BE], ndev);
out_free_irq_be_rx:
        free_irq(priv->rx_irqs[RAVB_BE], ndev);
out_free_irq_emac:
        free_irq(priv->emac_irq, 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, unsigned int txqueue)
{
        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);
        const struct ravb_hw_info *info = priv->info;
        struct net_device *ndev = priv->ndev;
        int error;

        netif_tx_stop_all_queues(ndev);

        /* Stop PTP Clock driver */
        if (info->no_ptp_cfg_active)
                ravb_ptp_stop(ndev);

        /* Wait for DMA stopping */
        if (ravb_stop_dma(ndev)) {
                /* If ravb_stop_dma() fails, the hardware is still operating
                 * for TX and/or RX. So, this should not call the following
                 * functions because ravb_dmac_init() is possible to fail too.
                 * Also, this should not retry ravb_stop_dma() again and again
                 * here because it's possible to wait forever. So, this just
                 * re-enables the TX and RX and skip the following
                 * re-initialization procedure.
                 */
                ravb_rcv_snd_enable(ndev);
                goto out;
        }

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

        /* Device init */
        error = ravb_dmac_init(ndev);
        if (error) {
                /* If ravb_dmac_init() fails, descriptors are freed. So, this
                 * should return here to avoid re-enabling the TX and RX in
                 * ravb_emac_init().
                 */
                netdev_err(ndev, "%s: ravb_dmac_init() failed, error %d\n",
                           __func__, error);
                return;
        }
        ravb_emac_init(ndev);

out:
        /* Initialise PTP Clock driver */
        if (info->no_ptp_cfg_active)
                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);
        unsigned int num_tx_desc = priv->num_tx_desc;
        u16 q = skb_get_queue_mapping(skb);
        struct ravb_tstamp_skb *ts_skb;
        struct ravb_tx_desc *desc;
        unsigned long flags;
        u32 dma_addr;
        void *buffer;
        u32 entry;
        u32 len;

        spin_lock_irqsave(&priv->lock, flags);
        if (priv->cur_tx[q] - priv->dirty_tx[q] > (priv->num_tx_ring[q] - 1) *
            num_tx_desc) {
                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;
        }

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

        entry = priv->cur_tx[q] % (priv->num_tx_ring[q] * num_tx_desc);
        priv->tx_skb[q][entry / num_tx_desc] = skb;

        if (num_tx_desc > 1) {
                buffer = PTR_ALIGN(priv->tx_align[q], DPTR_ALIGN) +
                         entry / num_tx_desc * DPTR_ALIGN;
                len = PTR_ALIGN(skb->data, DPTR_ALIGN) - skb->data;

                /* Zero length DMA descriptors are problematic as they seem
                 * to terminate DMA transfers. Avoid them by simply using a
                 * length of DPTR_ALIGN (4) when skb data is aligned to
                 * DPTR_ALIGN.
                 *
                 * As skb is guaranteed to have at least ETH_ZLEN (60)
                 * bytes of data by the call to skb_put_padto() above this
                 * is safe with respect to both the length of the first DMA
                 * descriptor (len) overflowing the available data and the
                 * length of the second DMA descriptor (skb->len - len)
                 * being negative.
                 */
                if (len == 0)
                        len = DPTR_ALIGN;

                memcpy(buffer, skb->data, len);
                dma_addr = dma_map_single(ndev->dev.parent, buffer, len,
                                          DMA_TO_DEVICE);
                if (dma_mapping_error(ndev->dev.parent, dma_addr))
                        goto drop;

                desc = &priv->tx_ring[q][entry];
                desc->ds_tagl = cpu_to_le16(len);
                desc->dptr = cpu_to_le32(dma_addr);

                buffer = skb->data + len;
                len = skb->len - len;
                dma_addr = dma_map_single(ndev->dev.parent, buffer, len,
                                          DMA_TO_DEVICE);
                if (dma_mapping_error(ndev->dev.parent, dma_addr))
                        goto unmap;

                desc++;
        } else {
                desc = &priv->tx_ring[q][entry];
                len = skb->len;
                dma_addr = dma_map_single(ndev->dev.parent, skb->data, skb->len,
                                          DMA_TO_DEVICE);
                if (dma_mapping_error(ndev->dev.parent, dma_addr))
                        goto drop;
        }
        desc->ds_tagl = cpu_to_le16(len);
        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) {
                        if (num_tx_desc > 1) {
                                desc--;
                                dma_unmap_single(ndev->dev.parent, dma_addr,
                                                 len, DMA_TO_DEVICE);
                        }
                        goto unmap;
                }
                ts_skb->skb = skb_get(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;
                desc->tagh_tsr = (ts_skb->tag >> 4) | TX_TSR;
                desc->ds_tagl |= cpu_to_le16(ts_skb->tag << 12);
        }

        skb_tx_timestamp(skb);
        /* Descriptor type must be set after all the above writes */
        dma_wmb();
        if (num_tx_desc > 1) {
                desc->die_dt = DT_FEND;
                desc--;
                desc->die_dt = DT_FSTART;
        } else {
                desc->die_dt = DT_FSINGLE;
        }
        ravb_modify(ndev, TCCR, TCCR_TSRQ0 << q, TCCR_TSRQ0 << q);

        priv->cur_tx[q] += num_tx_desc;
        if (priv->cur_tx[q] - priv->dirty_tx[q] >
            (priv->num_tx_ring[q] - 1) * num_tx_desc &&
            !ravb_tx_free(ndev, q, true))
                netif_stop_subqueue(ndev, q);

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

unmap:
        dma_unmap_single(ndev->dev.parent, le32_to_cpu(desc->dptr),
                         le16_to_cpu(desc->ds_tagl), DMA_TO_DEVICE);
drop:
        dev_kfree_skb_any(skb);
        priv->tx_skb[q][entry / num_tx_desc] = NULL;
        goto exit;
}

static u16 ravb_select_queue(struct net_device *ndev, struct sk_buff *skb,
                             struct net_device *sb_dev)
{
        /* 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);
        const struct ravb_hw_info *info = priv->info;
        struct net_device_stats *nstats, *stats0, *stats1;

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

        if (info->tx_counters) {
                nstats->tx_dropped += ravb_read(ndev, TROCR);
                ravb_write(ndev, 0, TROCR);     /* (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;

        spin_lock_irqsave(&priv->lock, flags);
        ravb_modify(ndev, ECMR, ECMR_PRM,
                    ndev->flags & IFF_PROMISC ? ECMR_PRM : 0);
        spin_unlock_irqrestore(&priv->lock, flags);
}

/* Device close function for Ethernet AVB */
static int ravb_close(struct net_device *ndev)
{
        struct device_node *np = ndev->dev.parent->of_node;
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;
        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, RIC2);
        ravb_write(ndev, 0, TIC);

        /* Stop PTP Clock driver */
        if (info->no_ptp_cfg_active)
                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_skb(ts_skb->skb);
                kfree(ts_skb);
        }

        /* PHY disconnect */
        if (ndev->phydev) {
                phy_stop(ndev->phydev);
                phy_disconnect(ndev->phydev);
                if (of_phy_is_fixed_link(np))
                        of_phy_deregister_fixed_link(np);
        }

        if (info->multi_irqs) {
                free_irq(priv->tx_irqs[RAVB_NC], ndev);
                free_irq(priv->rx_irqs[RAVB_NC], ndev);
                free_irq(priv->tx_irqs[RAVB_BE], ndev);
                free_irq(priv->rx_irqs[RAVB_BE], ndev);
                free_irq(priv->emac_irq, ndev);
        }
        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;
        switch (priv->tstamp_rx_ctrl & RAVB_RXTSTAMP_TYPE) {
        case RAVB_RXTSTAMP_TYPE_V2_L2_EVENT:
                config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L2_EVENT;
                break;
        case RAVB_RXTSTAMP_TYPE_ALL:
                config.rx_filter = HWTSTAMP_FILTER_ALL;
                break;
        default:
                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 phy_device *phydev = ndev->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 int ravb_change_mtu(struct net_device *ndev, int new_mtu)
{
        struct ravb_private *priv = netdev_priv(ndev);

        ndev->mtu = new_mtu;

        if (netif_running(ndev)) {
                synchronize_irq(priv->emac_irq);
                ravb_emac_init(ndev);
        }

        netdev_update_features(ndev);

        return 0;
}

static void ravb_set_rx_csum(struct net_device *ndev, bool enable)
{
        struct ravb_private *priv = netdev_priv(ndev);
        unsigned long flags;

        spin_lock_irqsave(&priv->lock, flags);

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

        /* Modify RX Checksum setting */
        ravb_modify(ndev, ECMR, ECMR_RCSC, enable ? ECMR_RCSC : 0);

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

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

static int ravb_set_features_rx_csum(struct net_device *ndev,
                                     netdev_features_t features)
{
        netdev_features_t changed = ndev->features ^ features;

        if (changed & NETIF_F_RXCSUM)
                ravb_set_rx_csum(ndev, features & NETIF_F_RXCSUM);

        ndev->features = features;

        return 0;
}

static int ravb_set_features(struct net_device *ndev,
                             netdev_features_t features)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;

        return info->set_rx_csum_feature(ndev, features);
}

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_eth_ioctl          = ravb_do_ioctl,
        .ndo_change_mtu         = ravb_change_mtu,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = eth_mac_addr,
        .ndo_set_features       = ravb_set_features,
};

/* 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 const struct ravb_hw_info ravb_gen3_hw_info = {
        .rx_ring_free = ravb_rx_ring_free,
        .rx_ring_format = ravb_rx_ring_format,
        .alloc_rx_desc = ravb_alloc_rx_desc,
        .receive = ravb_rcar_rx,
        .set_rate = ravb_set_rate,
        .set_rx_csum_feature = ravb_set_features_rx_csum,
        .dmac_init = ravb_rcar_dmac_init,
        .emac_init = ravb_rcar_emac_init,
        .gstrings_stats = ravb_gstrings_stats,
        .gstrings_size = sizeof(ravb_gstrings_stats),
        .net_hw_features = NETIF_F_RXCSUM,
        .net_features = NETIF_F_RXCSUM,
        .stats_len = ARRAY_SIZE(ravb_gstrings_stats),
        .max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,
        .internal_delay = 1,
        .tx_counters = 1,
        .multi_irqs = 1,
        .ptp_cfg_active = 1,
};

static const struct ravb_hw_info ravb_gen2_hw_info = {
        .rx_ring_free = ravb_rx_ring_free,
        .rx_ring_format = ravb_rx_ring_format,
        .alloc_rx_desc = ravb_alloc_rx_desc,
        .receive = ravb_rcar_rx,
        .set_rate = ravb_set_rate,
        .set_rx_csum_feature = ravb_set_features_rx_csum,
        .dmac_init = ravb_rcar_dmac_init,
        .emac_init = ravb_rcar_emac_init,
        .gstrings_stats = ravb_gstrings_stats,
        .gstrings_size = sizeof(ravb_gstrings_stats),
        .net_hw_features = NETIF_F_RXCSUM,
        .net_features = NETIF_F_RXCSUM,
        .stats_len = ARRAY_SIZE(ravb_gstrings_stats),
        .max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,
        .aligned_tx = 1,
        .no_ptp_cfg_active = 1,
};

static const struct of_device_id ravb_match_table[] = {
        { .compatible = "renesas,etheravb-r8a7790", .data = &ravb_gen2_hw_info },
        { .compatible = "renesas,etheravb-r8a7794", .data = &ravb_gen2_hw_info },
        { .compatible = "renesas,etheravb-rcar-gen2", .data = &ravb_gen2_hw_info },
        { .compatible = "renesas,etheravb-r8a7795", .data = &ravb_gen3_hw_info },
        { .compatible = "renesas,etheravb-rcar-gen3", .data = &ravb_gen3_hw_info },
        { }
};
MODULE_DEVICE_TABLE(of, ravb_match_table);

static int ravb_set_gti(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        struct device *dev = ndev->dev.parent;
        unsigned long rate;
        uint64_t inc;

        rate = clk_get_rate(priv->clk);
        if (!rate)
                return -EINVAL;

        inc = 1000000000ULL << 20;
        do_div(inc, rate);

        if (inc < GTI_TIV_MIN || inc > GTI_TIV_MAX) {
                dev_err(dev, "gti.tiv increment 0x%llx is outside the range 0x%x - 0x%x\n",
                        inc, GTI_TIV_MIN, GTI_TIV_MAX);
                return -EINVAL;
        }

        ravb_write(ndev, inc, GTI);

        return 0;
}

static void ravb_set_config_mode(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;

        if (info->no_ptp_cfg_active) {
                ravb_modify(ndev, CCC, CCC_OPC, CCC_OPC_CONFIG);
                /* Set CSEL value */
                ravb_modify(ndev, CCC, CCC_CSEL, CCC_CSEL_HPB);
        } else {
                ravb_modify(ndev, CCC, CCC_OPC, CCC_OPC_CONFIG |
                            CCC_GAC | CCC_CSEL_HPB);
        }
}

/* Set tx and rx clock internal delay modes */
static void ravb_parse_delay_mode(struct device_node *np, struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        bool explicit_delay = false;
        u32 delay;

        if (!of_property_read_u32(np, "rx-internal-delay-ps", &delay)) {
                /* Valid values are 0 and 1800, according to DT bindings */
                priv->rxcidm = !!delay;
                explicit_delay = true;
        }
        if (!of_property_read_u32(np, "tx-internal-delay-ps", &delay)) {
                /* Valid values are 0 and 2000, according to DT bindings */
                priv->txcidm = !!delay;
                explicit_delay = true;
        }

        if (explicit_delay)
                return;

        /* Fall back to legacy rgmii-*id behavior */
        if (priv->phy_interface == PHY_INTERFACE_MODE_RGMII_ID ||
            priv->phy_interface == PHY_INTERFACE_MODE_RGMII_RXID) {
                priv->rxcidm = 1;
                priv->rgmii_override = 1;
        }

        if (priv->phy_interface == PHY_INTERFACE_MODE_RGMII_ID ||
            priv->phy_interface == PHY_INTERFACE_MODE_RGMII_TXID) {
                priv->txcidm = 1;
                priv->rgmii_override = 1;
        }
}

static void ravb_set_delay_mode(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        u32 set = 0;

        if (priv->rxcidm)
                set |= APSR_RDM;
        if (priv->txcidm)
                set |= APSR_TDM;
        ravb_modify(ndev, APSR, APSR_RDM | APSR_TDM, set);
}

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

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

        rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
        if (IS_ERR(rstc))
                return dev_err_probe(&pdev->dev, PTR_ERR(rstc),
                                     "failed to get cpg reset\n");

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

        info = of_device_get_match_data(&pdev->dev);

        ndev->features = info->net_features;
        ndev->hw_features = info->net_hw_features;

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

        if (info->multi_irqs)
                irq = platform_get_irq_byname(pdev, "ch22");
        else
                irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
                error = irq;
                goto out_release;
        }
        ndev->irq = irq;

        SET_NETDEV_DEV(ndev, &pdev->dev);

        priv = netdev_priv(ndev);
        priv->info = info;
        priv->rstc = rstc;
        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_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(priv->addr)) {
                error = PTR_ERR(priv->addr);
                goto out_release;
        }

        /* The Ether-specific entries in the device structure. */
        ndev->base_addr = res->start;

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

        error = of_get_phy_mode(np, &priv->phy_interface);
        if (error && error != -ENODEV)
                goto out_release;

        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");

        if (info->multi_irqs) {
                irq = platform_get_irq_byname(pdev, "ch24");
                if (irq < 0) {
                        error = irq;
                        goto out_release;
                }
                priv->emac_irq = irq;
                for (i = 0; i < NUM_RX_QUEUE; i++) {
                        irq = platform_get_irq_byname(pdev, ravb_rx_irqs[i]);
                        if (irq < 0) {
                                error = irq;
                                goto out_release;
                        }
                        priv->rx_irqs[i] = irq;
                }
                for (i = 0; i < NUM_TX_QUEUE; i++) {
                        irq = platform_get_irq_byname(pdev, ravb_tx_irqs[i]);
                        if (irq < 0) {
                                error = irq;
                                goto out_release;
                        }
                        priv->tx_irqs[i] = irq;
                }
        }

        priv->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(priv->clk)) {
                error = PTR_ERR(priv->clk);
                goto out_release;
        }

        priv->refclk = devm_clk_get_optional(&pdev->dev, "refclk");
        if (IS_ERR(priv->refclk)) {
                error = PTR_ERR(priv->refclk);
                goto out_release;
        }
        clk_prepare_enable(priv->refclk);

        ndev->max_mtu = 2048 - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN);
        ndev->min_mtu = ETH_MIN_MTU;

        /* FIXME: R-Car Gen2 has 4byte alignment restriction for tx buffer
         * Use two descriptor to handle such situation. First descriptor to
         * handle aligned data buffer and second descriptor to handle the
         * overflow data because of alignment.
         */
        priv->num_tx_desc = info->aligned_tx ? 2 : 1;

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

        /* Set AVB config mode */
        ravb_set_config_mode(ndev);

        /* Set GTI value */
        error = ravb_set_gti(ndev);
        if (error)
                goto out_disable_refclk;

        /* Request GTI loading */
        ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);

        if (info->internal_delay) {
                ravb_parse_delay_mode(np, ndev);
                ravb_set_delay_mode(ndev);
        }

        /* Allocate descriptor base address table */
        priv->desc_bat_size = sizeof(struct ravb_desc) * DBAT_ENTRY_NUM;
        priv->desc_bat = dma_alloc_coherent(ndev->dev.parent, priv->desc_bat_size,
                                            &priv->desc_bat_dma, GFP_KERNEL);
        if (!priv->desc_bat) {
                dev_err(&pdev->dev,
                        "Cannot allocate desc base address table (size %d bytes)\n",
                        priv->desc_bat_size);
                error = -ENOMEM;
                goto out_disable_refclk;
        }
        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);

        /* Initialise PTP Clock driver */
        if (info->ptp_cfg_active)
                ravb_ptp_init(ndev, pdev);

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

        /* Read and set MAC address */
        ravb_read_mac_address(np, ndev);
        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(&pdev->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;

        device_set_wakeup_capable(&pdev->dev, 1);

        /* 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(ndev->dev.parent, priv->desc_bat_size, priv->desc_bat,
                          priv->desc_bat_dma);

        /* Stop PTP Clock driver */
        if (info->ptp_cfg_active)
                ravb_ptp_stop(ndev);
out_disable_refclk:
        clk_disable_unprepare(priv->refclk);
out_release:
        free_netdev(ndev);

        pm_runtime_put(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
        reset_control_assert(rstc);
        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);
        const struct ravb_hw_info *info = priv->info;

        /* Stop PTP Clock driver */
        if (info->ptp_cfg_active)
                ravb_ptp_stop(ndev);

        clk_disable_unprepare(priv->refclk);

        dma_free_coherent(ndev->dev.parent, 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);
        reset_control_assert(priv->rstc);
        free_netdev(ndev);
        platform_set_drvdata(pdev, NULL);

        return 0;
}

static int ravb_wol_setup(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);

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

        /* Only allow ECI interrupts */
        synchronize_irq(priv->emac_irq);
        napi_disable(&priv->napi[RAVB_NC]);
        napi_disable(&priv->napi[RAVB_BE]);
        ravb_write(ndev, ECSIPR_MPDIP, ECSIPR);

        /* Enable MagicPacket */
        ravb_modify(ndev, ECMR, ECMR_MPDE, ECMR_MPDE);

        return enable_irq_wake(priv->emac_irq);
}

static int ravb_wol_restore(struct net_device *ndev)
{
        struct ravb_private *priv = netdev_priv(ndev);
        int ret;

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

        /* Disable MagicPacket */
        ravb_modify(ndev, ECMR, ECMR_MPDE, 0);

        ret = ravb_close(ndev);
        if (ret < 0)
                return ret;

        return disable_irq_wake(priv->emac_irq);
}

static int __maybe_unused ravb_suspend(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct ravb_private *priv = netdev_priv(ndev);
        int ret;

        if (!netif_running(ndev))
                return 0;

        netif_device_detach(ndev);

        if (priv->wol_enabled)
                ret = ravb_wol_setup(ndev);
        else
                ret = ravb_close(ndev);

        return ret;
}

static int __maybe_unused ravb_resume(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct ravb_private *priv = netdev_priv(ndev);
        const struct ravb_hw_info *info = priv->info;
        int ret = 0;

        /* If WoL is enabled set reset mode to rearm the WoL logic */
        if (priv->wol_enabled)
                ravb_write(ndev, CCC_OPC_RESET, CCC);

        /* All register have been reset to default values.
         * Restore all registers which where setup at probe time and
         * reopen device if it was running before system suspended.
         */

        /* Set AVB config mode */
        ravb_set_config_mode(ndev);

        /* Set GTI value */
        ret = ravb_set_gti(ndev);
        if (ret)
                return ret;

        /* Request GTI loading */
        ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);

        if (info->internal_delay)
                ravb_set_delay_mode(ndev);

        /* Restore descriptor base address table */
        ravb_write(ndev, priv->desc_bat_dma, DBAT);

        if (netif_running(ndev)) {
                if (priv->wol_enabled) {
                        ret = ravb_wol_restore(ndev);
                        if (ret)
                                return ret;
                }
                ret = ravb_open(ndev);
                if (ret < 0)
                        return ret;
                netif_device_attach(ndev);
        }

        return ret;
}

static int __maybe_unused 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 = {
        SET_SYSTEM_SLEEP_PM_OPS(ravb_suspend, ravb_resume)
        SET_RUNTIME_PM_OPS(ravb_runtime_nop, ravb_runtime_nop, NULL)
};

static struct platform_driver ravb_driver = {
        .probe          = ravb_probe,
        .remove         = ravb_remove,
        .driver = {
                .name   = "ravb",
                .pm     = &ravb_dev_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");