/* SPDX-License-Identifier: GPL-2.0+ */
/* Copyright (C) 2018 Microchip Technology Inc. */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/crc32.h>
#include <linux/microchipphy.h>
#include <linux/net_tstamp.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/phy.h>
#include <linux/phy_fixed.h>
#include <linux/rtnetlink.h>
#include <linux/iopoll.h>
#include <linux/crc16.h>
#include "lan743x_main.h"
#include "lan743x_ethtool.h"

static void lan743x_pci_cleanup(struct lan743x_adapter *adapter)
{
        pci_release_selected_regions(adapter->pdev,
                                     pci_select_bars(adapter->pdev,
                                                     IORESOURCE_MEM));
        pci_disable_device(adapter->pdev);
}

static int lan743x_pci_init(struct lan743x_adapter *adapter,
                            struct pci_dev *pdev)
{
        unsigned long bars = 0;
        int ret;

        adapter->pdev = pdev;
        ret = pci_enable_device_mem(pdev);
        if (ret)
                goto return_error;

        netif_info(adapter, probe, adapter->netdev,
                   "PCI: Vendor ID = 0x%04X, Device ID = 0x%04X\n",
                   pdev->vendor, pdev->device);
        bars = pci_select_bars(pdev, IORESOURCE_MEM);
        if (!test_bit(0, &bars))
                goto disable_device;

        ret = pci_request_selected_regions(pdev, bars, DRIVER_NAME);
        if (ret)
                goto disable_device;

        pci_set_master(pdev);
        return 0;

disable_device:
        pci_disable_device(adapter->pdev);

return_error:
        return ret;
}

u32 lan743x_csr_read(struct lan743x_adapter *adapter, int offset)
{
        return ioread32(&adapter->csr.csr_address[offset]);
}

void lan743x_csr_write(struct lan743x_adapter *adapter, int offset,
                       u32 data)
{
        iowrite32(data, &adapter->csr.csr_address[offset]);
}

#define LAN743X_CSR_READ_OP(offset)     lan743x_csr_read(adapter, offset)

static int lan743x_csr_light_reset(struct lan743x_adapter *adapter)
{
        u32 data;

        data = lan743x_csr_read(adapter, HW_CFG);
        data |= HW_CFG_LRST_;
        lan743x_csr_write(adapter, HW_CFG, data);

        return readx_poll_timeout(LAN743X_CSR_READ_OP, HW_CFG, data,
                                  !(data & HW_CFG_LRST_), 100000, 10000000);
}

static int lan743x_csr_wait_for_bit(struct lan743x_adapter *adapter,
                                    int offset, u32 bit_mask,
                                    int target_value, int usleep_min,
                                    int usleep_max, int count)
{
        u32 data;

        return readx_poll_timeout(LAN743X_CSR_READ_OP, offset, data,
                                  target_value == ((data & bit_mask) ? 1 : 0),
                                  usleep_max, usleep_min * count);
}

static int lan743x_csr_init(struct lan743x_adapter *adapter)
{
        struct lan743x_csr *csr = &adapter->csr;
        resource_size_t bar_start, bar_length;
        int result;

        bar_start = pci_resource_start(adapter->pdev, 0);
        bar_length = pci_resource_len(adapter->pdev, 0);
        csr->csr_address = devm_ioremap(&adapter->pdev->dev,
                                        bar_start, bar_length);
        if (!csr->csr_address) {
                result = -ENOMEM;
                goto clean_up;
        }

        csr->id_rev = lan743x_csr_read(adapter, ID_REV);
        csr->fpga_rev = lan743x_csr_read(adapter, FPGA_REV);
        netif_info(adapter, probe, adapter->netdev,
                   "ID_REV = 0x%08X, FPGA_REV = %d.%d\n",
                   csr->id_rev, FPGA_REV_GET_MAJOR_(csr->fpga_rev),
                   FPGA_REV_GET_MINOR_(csr->fpga_rev));
        if (!ID_REV_IS_VALID_CHIP_ID_(csr->id_rev)) {
                result = -ENODEV;
                goto clean_up;
        }

        csr->flags = LAN743X_CSR_FLAG_SUPPORTS_INTR_AUTO_SET_CLR;
        switch (csr->id_rev & ID_REV_CHIP_REV_MASK_) {
        case ID_REV_CHIP_REV_A0_:
                csr->flags |= LAN743X_CSR_FLAG_IS_A0;
                csr->flags &= ~LAN743X_CSR_FLAG_SUPPORTS_INTR_AUTO_SET_CLR;
                break;
        case ID_REV_CHIP_REV_B0_:
                csr->flags |= LAN743X_CSR_FLAG_IS_B0;
                break;
        }

        result = lan743x_csr_light_reset(adapter);
        if (result)
                goto clean_up;
        return 0;
clean_up:
        return result;
}

static void lan743x_intr_software_isr(struct lan743x_adapter *adapter)
{
        struct lan743x_intr *intr = &adapter->intr;

        /* disable the interrupt to prevent repeated re-triggering */
        lan743x_csr_write(adapter, INT_EN_CLR, INT_BIT_SW_GP_);
        intr->software_isr_flag = true;
        wake_up(&intr->software_isr_wq);
}

static void lan743x_tx_isr(void *context, u32 int_sts, u32 flags)
{
        struct lan743x_tx *tx = context;
        struct lan743x_adapter *adapter = tx->adapter;
        bool enable_flag = true;

        lan743x_csr_read(adapter, INT_EN_SET);
        if (flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CLEAR) {
                lan743x_csr_write(adapter, INT_EN_CLR,
                                  INT_BIT_DMA_TX_(tx->channel_number));
        }

        if (int_sts & INT_BIT_DMA_TX_(tx->channel_number)) {
                u32 ioc_bit = DMAC_INT_BIT_TX_IOC_(tx->channel_number);
                u32 dmac_int_sts;
                u32 dmac_int_en;

                if (flags & LAN743X_VECTOR_FLAG_SOURCE_STATUS_READ)
                        dmac_int_sts = lan743x_csr_read(adapter, DMAC_INT_STS);
                else
                        dmac_int_sts = ioc_bit;
                if (flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CHECK)
                        dmac_int_en = lan743x_csr_read(adapter,
                                                       DMAC_INT_EN_SET);
                else
                        dmac_int_en = ioc_bit;

                dmac_int_en &= ioc_bit;
                dmac_int_sts &= dmac_int_en;
                if (dmac_int_sts & ioc_bit) {
                        napi_schedule(&tx->napi);
                        enable_flag = false;/* poll func will enable later */
                }
        }

        if (enable_flag)
                /* enable isr */
                lan743x_csr_write(adapter, INT_EN_SET,
                                  INT_BIT_DMA_TX_(tx->channel_number));
}

static void lan743x_rx_isr(void *context, u32 int_sts, u32 flags)
{
        struct lan743x_rx *rx = context;
        struct lan743x_adapter *adapter = rx->adapter;
        bool enable_flag = true;

        if (flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CLEAR) {
                lan743x_csr_write(adapter, INT_EN_CLR,
                                  INT_BIT_DMA_RX_(rx->channel_number));
        }

        if (int_sts & INT_BIT_DMA_RX_(rx->channel_number)) {
                u32 rx_frame_bit = DMAC_INT_BIT_RXFRM_(rx->channel_number);
                u32 dmac_int_sts;
                u32 dmac_int_en;

                if (flags & LAN743X_VECTOR_FLAG_SOURCE_STATUS_READ)
                        dmac_int_sts = lan743x_csr_read(adapter, DMAC_INT_STS);
                else
                        dmac_int_sts = rx_frame_bit;
                if (flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CHECK)
                        dmac_int_en = lan743x_csr_read(adapter,
                                                       DMAC_INT_EN_SET);
                else
                        dmac_int_en = rx_frame_bit;

                dmac_int_en &= rx_frame_bit;
                dmac_int_sts &= dmac_int_en;
                if (dmac_int_sts & rx_frame_bit) {
                        napi_schedule(&rx->napi);
                        enable_flag = false;/* poll funct will enable later */
                }
        }

        if (enable_flag) {
                /* enable isr */
                lan743x_csr_write(adapter, INT_EN_SET,
                                  INT_BIT_DMA_RX_(rx->channel_number));
        }
}

static void lan743x_intr_shared_isr(void *context, u32 int_sts, u32 flags)
{
        struct lan743x_adapter *adapter = context;
        unsigned int channel;

        if (int_sts & INT_BIT_ALL_RX_) {
                for (channel = 0; channel < LAN743X_USED_RX_CHANNELS;
                        channel++) {
                        u32 int_bit = INT_BIT_DMA_RX_(channel);

                        if (int_sts & int_bit) {
                                lan743x_rx_isr(&adapter->rx[channel],
                                               int_bit, flags);
                                int_sts &= ~int_bit;
                        }
                }
        }
        if (int_sts & INT_BIT_ALL_TX_) {
                for (channel = 0; channel < LAN743X_USED_TX_CHANNELS;
                        channel++) {
                        u32 int_bit = INT_BIT_DMA_TX_(channel);

                        if (int_sts & int_bit) {
                                lan743x_tx_isr(&adapter->tx[channel],
                                               int_bit, flags);
                                int_sts &= ~int_bit;
                        }
                }
        }
        if (int_sts & INT_BIT_ALL_OTHER_) {
                if (int_sts & INT_BIT_SW_GP_) {
                        lan743x_intr_software_isr(adapter);
                        int_sts &= ~INT_BIT_SW_GP_;
                }
                if (int_sts & INT_BIT_1588_) {
                        lan743x_ptp_isr(adapter);
                        int_sts &= ~INT_BIT_1588_;
                }
        }
        if (int_sts)
                lan743x_csr_write(adapter, INT_EN_CLR, int_sts);
}

static irqreturn_t lan743x_intr_entry_isr(int irq, void *ptr)
{
        struct lan743x_vector *vector = ptr;
        struct lan743x_adapter *adapter = vector->adapter;
        irqreturn_t result = IRQ_NONE;
        u32 int_enables;
        u32 int_sts;

        if (vector->flags & LAN743X_VECTOR_FLAG_SOURCE_STATUS_READ) {
                int_sts = lan743x_csr_read(adapter, INT_STS);
        } else if (vector->flags &
                   (LAN743X_VECTOR_FLAG_SOURCE_STATUS_R2C |
                   LAN743X_VECTOR_FLAG_SOURCE_ENABLE_R2C)) {
                int_sts = lan743x_csr_read(adapter, INT_STS_R2C);
        } else {
                /* use mask as implied status */
                int_sts = vector->int_mask | INT_BIT_MAS_;
        }

        if (!(int_sts & INT_BIT_MAS_))
                goto irq_done;

        if (vector->flags & LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_CLEAR)
                /* disable vector interrupt */
                lan743x_csr_write(adapter,
                                  INT_VEC_EN_CLR,
                                  INT_VEC_EN_(vector->vector_index));

        if (vector->flags & LAN743X_VECTOR_FLAG_MASTER_ENABLE_CLEAR)
                /* disable master interrupt */
                lan743x_csr_write(adapter, INT_EN_CLR, INT_BIT_MAS_);

        if (vector->flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CHECK) {
                int_enables = lan743x_csr_read(adapter, INT_EN_SET);
        } else {
                /*  use vector mask as implied enable mask */
                int_enables = vector->int_mask;
        }

        int_sts &= int_enables;
        int_sts &= vector->int_mask;
        if (int_sts) {
                if (vector->handler) {
                        vector->handler(vector->context,
                                        int_sts, vector->flags);
                } else {
                        /* disable interrupts on this vector */
                        lan743x_csr_write(adapter, INT_EN_CLR,
                                          vector->int_mask);
                }
                result = IRQ_HANDLED;
        }

        if (vector->flags & LAN743X_VECTOR_FLAG_MASTER_ENABLE_SET)
                /* enable master interrupt */
                lan743x_csr_write(adapter, INT_EN_SET, INT_BIT_MAS_);

        if (vector->flags & LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_SET)
                /* enable vector interrupt */
                lan743x_csr_write(adapter,
                                  INT_VEC_EN_SET,
                                  INT_VEC_EN_(vector->vector_index));
irq_done:
        return result;
}

static int lan743x_intr_test_isr(struct lan743x_adapter *adapter)
{
        struct lan743x_intr *intr = &adapter->intr;
        int ret;

        intr->software_isr_flag = false;

        /* enable and activate test interrupt */
        lan743x_csr_write(adapter, INT_EN_SET, INT_BIT_SW_GP_);
        lan743x_csr_write(adapter, INT_SET, INT_BIT_SW_GP_);

        ret = wait_event_timeout(intr->software_isr_wq,
                                 intr->software_isr_flag,
                                 msecs_to_jiffies(200));

        /* disable test interrupt */
        lan743x_csr_write(adapter, INT_EN_CLR, INT_BIT_SW_GP_);

        return ret > 0 ? 0 : -ENODEV;
}

static int lan743x_intr_register_isr(struct lan743x_adapter *adapter,
                                     int vector_index, u32 flags,
                                     u32 int_mask,
                                     lan743x_vector_handler handler,
                                     void *context)
{
        struct lan743x_vector *vector = &adapter->intr.vector_list
                                        [vector_index];
        int ret;

        vector->adapter = adapter;
        vector->flags = flags;
        vector->vector_index = vector_index;
        vector->int_mask = int_mask;
        vector->handler = handler;
        vector->context = context;

        ret = request_irq(vector->irq,
                          lan743x_intr_entry_isr,
                          (flags & LAN743X_VECTOR_FLAG_IRQ_SHARED) ?
                          IRQF_SHARED : 0, DRIVER_NAME, vector);
        if (ret) {
                vector->handler = NULL;
                vector->context = NULL;
                vector->int_mask = 0;
                vector->flags = 0;
        }
        return ret;
}

static void lan743x_intr_unregister_isr(struct lan743x_adapter *adapter,
                                        int vector_index)
{
        struct lan743x_vector *vector = &adapter->intr.vector_list
                                        [vector_index];

        free_irq(vector->irq, vector);
        vector->handler = NULL;
        vector->context = NULL;
        vector->int_mask = 0;
        vector->flags = 0;
}

static u32 lan743x_intr_get_vector_flags(struct lan743x_adapter *adapter,
                                         u32 int_mask)
{
        int index;

        for (index = 0; index < LAN743X_MAX_VECTOR_COUNT; index++) {
                if (adapter->intr.vector_list[index].int_mask & int_mask)
                        return adapter->intr.vector_list[index].flags;
        }
        return 0;
}

static void lan743x_intr_close(struct lan743x_adapter *adapter)
{
        struct lan743x_intr *intr = &adapter->intr;
        int index = 0;

        lan743x_csr_write(adapter, INT_EN_CLR, INT_BIT_MAS_);
        lan743x_csr_write(adapter, INT_VEC_EN_CLR, 0x000000FF);

        for (index = 0; index < LAN743X_MAX_VECTOR_COUNT; index++) {
                if (intr->flags & INTR_FLAG_IRQ_REQUESTED(index)) {
                        lan743x_intr_unregister_isr(adapter, index);
                        intr->flags &= ~INTR_FLAG_IRQ_REQUESTED(index);
                }
        }

        if (intr->flags & INTR_FLAG_MSI_ENABLED) {
                pci_disable_msi(adapter->pdev);
                intr->flags &= ~INTR_FLAG_MSI_ENABLED;
        }

        if (intr->flags & INTR_FLAG_MSIX_ENABLED) {
                pci_disable_msix(adapter->pdev);
                intr->flags &= ~INTR_FLAG_MSIX_ENABLED;
        }
}

static int lan743x_intr_open(struct lan743x_adapter *adapter)
{
        struct msix_entry msix_entries[LAN743X_MAX_VECTOR_COUNT];
        struct lan743x_intr *intr = &adapter->intr;
        u32 int_vec_en_auto_clr = 0;
        u32 int_vec_map0 = 0;
        u32 int_vec_map1 = 0;
        int ret = -ENODEV;
        int index = 0;
        u32 flags = 0;

        intr->number_of_vectors = 0;

        /* Try to set up MSIX interrupts */
        memset(&msix_entries[0], 0,
               sizeof(struct msix_entry) * LAN743X_MAX_VECTOR_COUNT);
        for (index = 0; index < LAN743X_MAX_VECTOR_COUNT; index++)
                msix_entries[index].entry = index;
        ret = pci_enable_msix_range(adapter->pdev,
                                    msix_entries, 1,
                                    1 + LAN743X_USED_TX_CHANNELS +
                                    LAN743X_USED_RX_CHANNELS);

        if (ret > 0) {
                intr->flags |= INTR_FLAG_MSIX_ENABLED;
                intr->number_of_vectors = ret;
                intr->using_vectors = true;
                for (index = 0; index < intr->number_of_vectors; index++)
                        intr->vector_list[index].irq = msix_entries
                                                       [index].vector;
                netif_info(adapter, ifup, adapter->netdev,
                           "using MSIX interrupts, number of vectors = %d\n",
                           intr->number_of_vectors);
        }

        /* If MSIX failed try to setup using MSI interrupts */
        if (!intr->number_of_vectors) {
                if (!(adapter->csr.flags & LAN743X_CSR_FLAG_IS_A0)) {
                        if (!pci_enable_msi(adapter->pdev)) {
                                intr->flags |= INTR_FLAG_MSI_ENABLED;
                                intr->number_of_vectors = 1;
                                intr->using_vectors = true;
                                intr->vector_list[0].irq =
                                        adapter->pdev->irq;
                                netif_info(adapter, ifup, adapter->netdev,
                                           "using MSI interrupts, number of vectors = %d\n",
                                           intr->number_of_vectors);
                        }
                }
        }

        /* If MSIX, and MSI failed, setup using legacy interrupt */
        if (!intr->number_of_vectors) {
                intr->number_of_vectors = 1;
                intr->using_vectors = false;
                intr->vector_list[0].irq = intr->irq;
                netif_info(adapter, ifup, adapter->netdev,
                           "using legacy interrupts\n");
        }

        /* At this point we must have at least one irq */
        lan743x_csr_write(adapter, INT_VEC_EN_CLR, 0xFFFFFFFF);

        /* map all interrupts to vector 0 */
        lan743x_csr_write(adapter, INT_VEC_MAP0, 0x00000000);
        lan743x_csr_write(adapter, INT_VEC_MAP1, 0x00000000);
        lan743x_csr_write(adapter, INT_VEC_MAP2, 0x00000000);
        flags = LAN743X_VECTOR_FLAG_SOURCE_STATUS_READ |
                LAN743X_VECTOR_FLAG_SOURCE_STATUS_W2C |
                LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CHECK |
                LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CLEAR;

        if (intr->using_vectors) {
                flags |= LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_CLEAR |
                         LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_SET;
        } else {
                flags |= LAN743X_VECTOR_FLAG_MASTER_ENABLE_CLEAR |
                         LAN743X_VECTOR_FLAG_MASTER_ENABLE_SET |
                         LAN743X_VECTOR_FLAG_IRQ_SHARED;
        }

        if (adapter->csr.flags & LAN743X_CSR_FLAG_SUPPORTS_INTR_AUTO_SET_CLR) {
                flags &= ~LAN743X_VECTOR_FLAG_SOURCE_STATUS_READ;
                flags &= ~LAN743X_VECTOR_FLAG_SOURCE_STATUS_W2C;
                flags &= ~LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CLEAR;
                flags &= ~LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CHECK;
                flags |= LAN743X_VECTOR_FLAG_SOURCE_STATUS_R2C;
                flags |= LAN743X_VECTOR_FLAG_SOURCE_ENABLE_R2C;
        }

        init_waitqueue_head(&intr->software_isr_wq);

        ret = lan743x_intr_register_isr(adapter, 0, flags,
                                        INT_BIT_ALL_RX_ | INT_BIT_ALL_TX_ |
                                        INT_BIT_ALL_OTHER_,
                                        lan743x_intr_shared_isr, adapter);
        if (ret)
                goto clean_up;
        intr->flags |= INTR_FLAG_IRQ_REQUESTED(0);

        if (intr->using_vectors)
                lan743x_csr_write(adapter, INT_VEC_EN_SET,
                                  INT_VEC_EN_(0));

        if (!(adapter->csr.flags & LAN743X_CSR_FLAG_IS_A0)) {
                lan743x_csr_write(adapter, INT_MOD_CFG0, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_CFG1, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_CFG2, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_CFG3, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_CFG4, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_CFG5, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_CFG6, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_CFG7, LAN743X_INT_MOD);
                lan743x_csr_write(adapter, INT_MOD_MAP0, 0x00005432);
                lan743x_csr_write(adapter, INT_MOD_MAP1, 0x00000001);
                lan743x_csr_write(adapter, INT_MOD_MAP2, 0x00FFFFFF);
        }

        /* enable interrupts */
        lan743x_csr_write(adapter, INT_EN_SET, INT_BIT_MAS_);
        ret = lan743x_intr_test_isr(adapter);
        if (ret)
                goto clean_up;

        if (intr->number_of_vectors > 1) {
                int number_of_tx_vectors = intr->number_of_vectors - 1;

                if (number_of_tx_vectors > LAN743X_USED_TX_CHANNELS)
                        number_of_tx_vectors = LAN743X_USED_TX_CHANNELS;
                flags = LAN743X_VECTOR_FLAG_SOURCE_STATUS_READ |
                        LAN743X_VECTOR_FLAG_SOURCE_STATUS_W2C |
                        LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CHECK |
                        LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CLEAR |
                        LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_CLEAR |
                        LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_SET;

                if (adapter->csr.flags &
                   LAN743X_CSR_FLAG_SUPPORTS_INTR_AUTO_SET_CLR) {
                        flags = LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_SET |
                                LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_SET |
                                LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_CLEAR |
                                LAN743X_VECTOR_FLAG_SOURCE_STATUS_AUTO_CLEAR;
                }

                for (index = 0; index < number_of_tx_vectors; index++) {
                        u32 int_bit = INT_BIT_DMA_TX_(index);
                        int vector = index + 1;

                        /* map TX interrupt to vector */
                        int_vec_map1 |= INT_VEC_MAP1_TX_VEC_(index, vector);
                        lan743x_csr_write(adapter, INT_VEC_MAP1, int_vec_map1);

                        /* Remove TX interrupt from shared mask */
                        intr->vector_list[0].int_mask &= ~int_bit;
                        ret = lan743x_intr_register_isr(adapter, vector, flags,
                                                        int_bit, lan743x_tx_isr,
                                                        &adapter->tx[index]);
                        if (ret)
                                goto clean_up;
                        intr->flags |= INTR_FLAG_IRQ_REQUESTED(vector);
                        if (!(flags &
                            LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_SET))
                                lan743x_csr_write(adapter, INT_VEC_EN_SET,
                                                  INT_VEC_EN_(vector));
                }
        }
        if ((intr->number_of_vectors - LAN743X_USED_TX_CHANNELS) > 1) {
                int number_of_rx_vectors = intr->number_of_vectors -
                                           LAN743X_USED_TX_CHANNELS - 1;

                if (number_of_rx_vectors > LAN743X_USED_RX_CHANNELS)
                        number_of_rx_vectors = LAN743X_USED_RX_CHANNELS;

                flags = LAN743X_VECTOR_FLAG_SOURCE_STATUS_READ |
                        LAN743X_VECTOR_FLAG_SOURCE_STATUS_W2C |
                        LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CHECK |
                        LAN743X_VECTOR_FLAG_SOURCE_ENABLE_CLEAR |
                        LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_CLEAR |
                        LAN743X_VECTOR_FLAG_VECTOR_ENABLE_ISR_SET;

                if (adapter->csr.flags &
                    LAN743X_CSR_FLAG_SUPPORTS_INTR_AUTO_SET_CLR) {
                        flags = LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_CLEAR |
                                LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_SET |
                                LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_SET |
                                LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_CLEAR |
                                LAN743X_VECTOR_FLAG_SOURCE_STATUS_AUTO_CLEAR;
                }
                for (index = 0; index < number_of_rx_vectors; index++) {
                        int vector = index + 1 + LAN743X_USED_TX_CHANNELS;
                        u32 int_bit = INT_BIT_DMA_RX_(index);

                        /* map RX interrupt to vector */
                        int_vec_map0 |= INT_VEC_MAP0_RX_VEC_(index, vector);
                        lan743x_csr_write(adapter, INT_VEC_MAP0, int_vec_map0);
                        if (flags &
                            LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_CLEAR) {
                                int_vec_en_auto_clr |= INT_VEC_EN_(vector);
                                lan743x_csr_write(adapter, INT_VEC_EN_AUTO_CLR,
                                                  int_vec_en_auto_clr);
                        }

                        /* Remove RX interrupt from shared mask */
                        intr->vector_list[0].int_mask &= ~int_bit;
                        ret = lan743x_intr_register_isr(adapter, vector, flags,
                                                        int_bit, lan743x_rx_isr,
                                                        &adapter->rx[index]);
                        if (ret)
                                goto clean_up;
                        intr->flags |= INTR_FLAG_IRQ_REQUESTED(vector);

                        lan743x_csr_write(adapter, INT_VEC_EN_SET,
                                          INT_VEC_EN_(vector));
                }
        }
        return 0;

clean_up:
        lan743x_intr_close(adapter);
        return ret;
}

static int lan743x_dp_write(struct lan743x_adapter *adapter,
                            u32 select, u32 addr, u32 length, u32 *buf)
{
        u32 dp_sel;
        int i;

        if (lan743x_csr_wait_for_bit(adapter, DP_SEL, DP_SEL_DPRDY_,
                                     1, 40, 100, 100))
                return -EIO;
        dp_sel = lan743x_csr_read(adapter, DP_SEL);
        dp_sel &= ~DP_SEL_MASK_;
        dp_sel |= select;
        lan743x_csr_write(adapter, DP_SEL, dp_sel);

        for (i = 0; i < length; i++) {
                lan743x_csr_write(adapter, DP_ADDR, addr + i);
                lan743x_csr_write(adapter, DP_DATA_0, buf[i]);
                lan743x_csr_write(adapter, DP_CMD, DP_CMD_WRITE_);
                if (lan743x_csr_wait_for_bit(adapter, DP_SEL, DP_SEL_DPRDY_,
                                             1, 40, 100, 100))
                        return -EIO;
        }

        return 0;
}

static u32 lan743x_mac_mii_access(u16 id, u16 index, int read)
{
        u32 ret;

        ret = (id << MAC_MII_ACC_PHY_ADDR_SHIFT_) &
                MAC_MII_ACC_PHY_ADDR_MASK_;
        ret |= (index << MAC_MII_ACC_MIIRINDA_SHIFT_) &
                MAC_MII_ACC_MIIRINDA_MASK_;

        if (read)
                ret |= MAC_MII_ACC_MII_READ_;
        else
                ret |= MAC_MII_ACC_MII_WRITE_;
        ret |= MAC_MII_ACC_MII_BUSY_;

        return ret;
}

static int lan743x_mac_mii_wait_till_not_busy(struct lan743x_adapter *adapter)
{
        u32 data;

        return readx_poll_timeout(LAN743X_CSR_READ_OP, MAC_MII_ACC, data,
                                  !(data & MAC_MII_ACC_MII_BUSY_), 0, 1000000);
}

static int lan743x_mdiobus_read(struct mii_bus *bus, int phy_id, int index)
{
        struct lan743x_adapter *adapter = bus->priv;
        u32 val, mii_access;
        int ret;

        /* comfirm MII not busy */
        ret = lan743x_mac_mii_wait_till_not_busy(adapter);
        if (ret < 0)
                return ret;

        /* set the address, index & direction (read from PHY) */
        mii_access = lan743x_mac_mii_access(phy_id, index, MAC_MII_READ);
        lan743x_csr_write(adapter, MAC_MII_ACC, mii_access);
        ret = lan743x_mac_mii_wait_till_not_busy(adapter);
        if (ret < 0)
                return ret;

        val = lan743x_csr_read(adapter, MAC_MII_DATA);
        return (int)(val & 0xFFFF);
}

static int lan743x_mdiobus_write(struct mii_bus *bus,
                                 int phy_id, int index, u16 regval)
{
        struct lan743x_adapter *adapter = bus->priv;
        u32 val, mii_access;
        int ret;

        /* confirm MII not busy */
        ret = lan743x_mac_mii_wait_till_not_busy(adapter);
        if (ret < 0)
                return ret;
        val = (u32)regval;
        lan743x_csr_write(adapter, MAC_MII_DATA, val);

        /* set the address, index & direction (write to PHY) */
        mii_access = lan743x_mac_mii_access(phy_id, index, MAC_MII_WRITE);
        lan743x_csr_write(adapter, MAC_MII_ACC, mii_access);
        ret = lan743x_mac_mii_wait_till_not_busy(adapter);
        return ret;
}

static void lan743x_mac_set_address(struct lan743x_adapter *adapter,
                                    u8 *addr)
{
        u32 addr_lo, addr_hi;

        addr_lo = addr[0] |
                addr[1] << 8 |
                addr[2] << 16 |
                addr[3] << 24;
        addr_hi = addr[4] |
                addr[5] << 8;
        lan743x_csr_write(adapter, MAC_RX_ADDRL, addr_lo);
        lan743x_csr_write(adapter, MAC_RX_ADDRH, addr_hi);

        ether_addr_copy(adapter->mac_address, addr);
        netif_info(adapter, drv, adapter->netdev,
                   "MAC address set to %pM\n", addr);
}

static int lan743x_mac_init(struct lan743x_adapter *adapter)
{
        bool mac_address_valid = true;
        struct net_device *netdev;
        u32 mac_addr_hi = 0;
        u32 mac_addr_lo = 0;
        u32 data;

        netdev = adapter->netdev;

        /* disable auto duplex, and speed detection. Phylib does that */
        data = lan743x_csr_read(adapter, MAC_CR);
        data &= ~(MAC_CR_ADD_ | MAC_CR_ASD_);
        data |= MAC_CR_CNTR_RST_;
        lan743x_csr_write(adapter, MAC_CR, data);

        if (!is_valid_ether_addr(adapter->mac_address)) {
                mac_addr_hi = lan743x_csr_read(adapter, MAC_RX_ADDRH);
                mac_addr_lo = lan743x_csr_read(adapter, MAC_RX_ADDRL);
                adapter->mac_address[0] = mac_addr_lo & 0xFF;
                adapter->mac_address[1] = (mac_addr_lo >> 8) & 0xFF;
                adapter->mac_address[2] = (mac_addr_lo >> 16) & 0xFF;
                adapter->mac_address[3] = (mac_addr_lo >> 24) & 0xFF;
                adapter->mac_address[4] = mac_addr_hi & 0xFF;
                adapter->mac_address[5] = (mac_addr_hi >> 8) & 0xFF;

                if (((mac_addr_hi & 0x0000FFFF) == 0x0000FFFF) &&
                    mac_addr_lo == 0xFFFFFFFF) {
                        mac_address_valid = false;
                } else if (!is_valid_ether_addr(adapter->mac_address)) {
                        mac_address_valid = false;
                }

                if (!mac_address_valid)
                        eth_random_addr(adapter->mac_address);
        }
        lan743x_mac_set_address(adapter, adapter->mac_address);
        ether_addr_copy(netdev->dev_addr, adapter->mac_address);

        return 0;
}

static int lan743x_mac_open(struct lan743x_adapter *adapter)
{
        u32 temp;

        temp = lan743x_csr_read(adapter, MAC_RX);
        lan743x_csr_write(adapter, MAC_RX, temp | MAC_RX_RXEN_);
        temp = lan743x_csr_read(adapter, MAC_TX);
        lan743x_csr_write(adapter, MAC_TX, temp | MAC_TX_TXEN_);
        return 0;
}

static void lan743x_mac_close(struct lan743x_adapter *adapter)
{
        u32 temp;

        temp = lan743x_csr_read(adapter, MAC_TX);
        temp &= ~MAC_TX_TXEN_;
        lan743x_csr_write(adapter, MAC_TX, temp);
        lan743x_csr_wait_for_bit(adapter, MAC_TX, MAC_TX_TXD_,
                                 1, 1000, 20000, 100);

        temp = lan743x_csr_read(adapter, MAC_RX);
        temp &= ~MAC_RX_RXEN_;
        lan743x_csr_write(adapter, MAC_RX, temp);
        lan743x_csr_wait_for_bit(adapter, MAC_RX, MAC_RX_RXD_,
                                 1, 1000, 20000, 100);
}

static void lan743x_mac_flow_ctrl_set_enables(struct lan743x_adapter *adapter,
                                              bool tx_enable, bool rx_enable)
{
        u32 flow_setting = 0;

        /* set maximum pause time because when fifo space frees
         * up a zero value pause frame will be sent to release the pause
         */
        flow_setting = MAC_FLOW_CR_FCPT_MASK_;
        if (tx_enable)
                flow_setting |= MAC_FLOW_CR_TX_FCEN_;
        if (rx_enable)
                flow_setting |= MAC_FLOW_CR_RX_FCEN_;
        lan743x_csr_write(adapter, MAC_FLOW, flow_setting);
}

static int lan743x_mac_set_mtu(struct lan743x_adapter *adapter, int new_mtu)
{
        int enabled = 0;
        u32 mac_rx = 0;

        mac_rx = lan743x_csr_read(adapter, MAC_RX);
        if (mac_rx & MAC_RX_RXEN_) {
                enabled = 1;
                if (mac_rx & MAC_RX_RXD_) {
                        lan743x_csr_write(adapter, MAC_RX, mac_rx);
                        mac_rx &= ~MAC_RX_RXD_;
                }
                mac_rx &= ~MAC_RX_RXEN_;
                lan743x_csr_write(adapter, MAC_RX, mac_rx);
                lan743x_csr_wait_for_bit(adapter, MAC_RX, MAC_RX_RXD_,
                                         1, 1000, 20000, 100);
                lan743x_csr_write(adapter, MAC_RX, mac_rx | MAC_RX_RXD_);
        }

        mac_rx &= ~(MAC_RX_MAX_SIZE_MASK_);
        mac_rx |= (((new_mtu + ETH_HLEN + ETH_FCS_LEN)
                  << MAC_RX_MAX_SIZE_SHIFT_) & MAC_RX_MAX_SIZE_MASK_);
        lan743x_csr_write(adapter, MAC_RX, mac_rx);

        if (enabled) {
                mac_rx |= MAC_RX_RXEN_;
                lan743x_csr_write(adapter, MAC_RX, mac_rx);
        }
        return 0;
}

/* PHY */
static int lan743x_phy_reset(struct lan743x_adapter *adapter)
{
        u32 data;

        /* Only called with in probe, and before mdiobus_register */

        data = lan743x_csr_read(adapter, PMT_CTL);
        data |= PMT_CTL_ETH_PHY_RST_;
        lan743x_csr_write(adapter, PMT_CTL, data);

        return readx_poll_timeout(LAN743X_CSR_READ_OP, PMT_CTL, data,
                                  (!(data & PMT_CTL_ETH_PHY_RST_) &&
                                  (data & PMT_CTL_READY_)),
                                  50000, 1000000);
}

static void lan743x_phy_update_flowcontrol(struct lan743x_adapter *adapter,
                                           u8 duplex, u16 local_adv,
                                           u16 remote_adv)
{
        struct lan743x_phy *phy = &adapter->phy;
        u8 cap;

        if (phy->fc_autoneg)
                cap = mii_resolve_flowctrl_fdx(local_adv, remote_adv);
        else
                cap = phy->fc_request_control;

        lan743x_mac_flow_ctrl_set_enables(adapter,
                                          cap & FLOW_CTRL_TX,
                                          cap & FLOW_CTRL_RX);
}

static int lan743x_phy_init(struct lan743x_adapter *adapter)
{
        return lan743x_phy_reset(adapter);
}

static void lan743x_phy_link_status_change(struct net_device *netdev)
{
        struct lan743x_adapter *adapter = netdev_priv(netdev);
        struct phy_device *phydev = netdev->phydev;
        u32 data;

        phy_print_status(phydev);
        if (phydev->state == PHY_RUNNING) {
                struct ethtool_link_ksettings ksettings;
                int remote_advertisement = 0;
                int local_advertisement = 0;

                data = lan743x_csr_read(adapter, MAC_CR);

                /* set interface mode */
                if (phy_interface_is_rgmii(phydev))
                        /* RGMII */
                        data &= ~MAC_CR_MII_EN_;
                else
                        /* GMII */
                        data |= MAC_CR_MII_EN_;

                /* set duplex mode */
                if (phydev->duplex)
                        data |= MAC_CR_DPX_;
                else
                        data &= ~MAC_CR_DPX_;

                /* set bus speed */
                switch (phydev->speed) {
                case SPEED_10:
                        data &= ~MAC_CR_CFG_H_;
                        data &= ~MAC_CR_CFG_L_;
                break;
                case SPEED_100:
                        data &= ~MAC_CR_CFG_H_;
                        data |= MAC_CR_CFG_L_;
                break;
                case SPEED_1000:
                        data |= MAC_CR_CFG_H_;
                        data &= ~MAC_CR_CFG_L_;
                break;
                }
                lan743x_csr_write(adapter, MAC_CR, data);

                memset(&ksettings, 0, sizeof(ksettings));
                phy_ethtool_get_link_ksettings(netdev, &ksettings);
                local_advertisement =
                        linkmode_adv_to_mii_adv_t(phydev->advertising);
                remote_advertisement =
                        linkmode_adv_to_mii_adv_t(phydev->lp_advertising);

                lan743x_phy_update_flowcontrol(adapter,
                                               ksettings.base.duplex,
                                               local_advertisement,
                                               remote_advertisement);
                lan743x_ptp_update_latency(adapter, ksettings.base.speed);
        }
}

static void lan743x_phy_close(struct lan743x_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;

        phy_stop(netdev->phydev);
        phy_disconnect(netdev->phydev);
        netdev->phydev = NULL;
}

static int lan743x_phy_open(struct lan743x_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct lan743x_phy *phy = &adapter->phy;
        struct phy_device *phydev;
        int ret = -EIO;

        /* try devicetree phy, or fixed link */
        phydev = of_phy_get_and_connect(netdev, adapter->pdev->dev.of_node,
                                        lan743x_phy_link_status_change);

        if (!phydev) {
                /* try internal phy */
                phydev = phy_find_first(adapter->mdiobus);
                if (!phydev)
                        goto return_error;

                ret = phy_connect_direct(netdev, phydev,
                                         lan743x_phy_link_status_change,
                                         PHY_INTERFACE_MODE_GMII);
                if (ret)
                        goto return_error;
        }

        /* MAC doesn't support 1000T Half */
        phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);

        /* support both flow controls */
        phy_support_asym_pause(phydev);
        phy->fc_request_control = (FLOW_CTRL_RX | FLOW_CTRL_TX);
        phy->fc_autoneg = phydev->autoneg;

        phy_start(phydev);
        phy_start_aneg(phydev);
        phy_attached_info(phydev);
        return 0;

return_error:
        return ret;
}

static void lan743x_rfe_open(struct lan743x_adapter *adapter)
{
        lan743x_csr_write(adapter, RFE_RSS_CFG,
                RFE_RSS_CFG_UDP_IPV6_EX_ |
                RFE_RSS_CFG_TCP_IPV6_EX_ |
                RFE_RSS_CFG_IPV6_EX_ |
                RFE_RSS_CFG_UDP_IPV6_ |
                RFE_RSS_CFG_TCP_IPV6_ |
                RFE_RSS_CFG_IPV6_ |
                RFE_RSS_CFG_UDP_IPV4_ |
                RFE_RSS_CFG_TCP_IPV4_ |
                RFE_RSS_CFG_IPV4_ |
                RFE_RSS_CFG_VALID_HASH_BITS_ |
                RFE_RSS_CFG_RSS_QUEUE_ENABLE_ |
                RFE_RSS_CFG_RSS_HASH_STORE_ |
                RFE_RSS_CFG_RSS_ENABLE_);
}

static void lan743x_rfe_update_mac_address(struct lan743x_adapter *adapter)
{
        u8 *mac_addr;
        u32 mac_addr_hi = 0;
        u32 mac_addr_lo = 0;

        /* Add mac address to perfect Filter */
        mac_addr = adapter->mac_address;
        mac_addr_lo = ((((u32)(mac_addr[0])) << 0) |
                      (((u32)(mac_addr[1])) << 8) |
                      (((u32)(mac_addr[2])) << 16) |
                      (((u32)(mac_addr[3])) << 24));
        mac_addr_hi = ((((u32)(mac_addr[4])) << 0) |
                      (((u32)(mac_addr[5])) << 8));

        lan743x_csr_write(adapter, RFE_ADDR_FILT_LO(0), mac_addr_lo);
        lan743x_csr_write(adapter, RFE_ADDR_FILT_HI(0),
                          mac_addr_hi | RFE_ADDR_FILT_HI_VALID_);
}

static void lan743x_rfe_set_multicast(struct lan743x_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        u32 hash_table[DP_SEL_VHF_HASH_LEN];
        u32 rfctl;
        u32 data;

        rfctl = lan743x_csr_read(adapter, RFE_CTL);
        rfctl &= ~(RFE_CTL_AU_ | RFE_CTL_AM_ |
                 RFE_CTL_DA_PERFECT_ | RFE_CTL_MCAST_HASH_);
        rfctl |= RFE_CTL_AB_;
        if (netdev->flags & IFF_PROMISC) {
                rfctl |= RFE_CTL_AM_ | RFE_CTL_AU_;
        } else {
                if (netdev->flags & IFF_ALLMULTI)
                        rfctl |= RFE_CTL_AM_;
        }

        memset(hash_table, 0, DP_SEL_VHF_HASH_LEN * sizeof(u32));
        if (netdev_mc_count(netdev)) {
                struct netdev_hw_addr *ha;
                int i;

                rfctl |= RFE_CTL_DA_PERFECT_;
                i = 1;
                netdev_for_each_mc_addr(ha, netdev) {
                        /* set first 32 into Perfect Filter */
                        if (i < 33) {
                                lan743x_csr_write(adapter,
                                                  RFE_ADDR_FILT_HI(i), 0);
                                data = ha->addr[3];
                                data = ha->addr[2] | (data << 8);
                                data = ha->addr[1] | (data << 8);
                                data = ha->addr[0] | (data << 8);
                                lan743x_csr_write(adapter,
                                                  RFE_ADDR_FILT_LO(i), data);
                                data = ha->addr[5];
                                data = ha->addr[4] | (data << 8);
                                data |= RFE_ADDR_FILT_HI_VALID_;
                                lan743x_csr_write(adapter,
                                                  RFE_ADDR_FILT_HI(i), data);
                        } else {
                                u32 bitnum = (ether_crc(ETH_ALEN, ha->addr) >>
                                             23) & 0x1FF;
                                hash_table[bitnum / 32] |= (1 << (bitnum % 32));
                                rfctl |= RFE_CTL_MCAST_HASH_;
                        }
                        i++;
                }
        }

        lan743x_dp_write(adapter, DP_SEL_RFE_RAM,
                         DP_SEL_VHF_VLAN_LEN,
                         DP_SEL_VHF_HASH_LEN, hash_table);
        lan743x_csr_write(adapter, RFE_CTL, rfctl);
}

static int lan743x_dmac_init(struct lan743x_adapter *adapter)
{
        u32 data = 0;

        lan743x_csr_write(adapter, DMAC_CMD, DMAC_CMD_SWR_);
        lan743x_csr_wait_for_bit(adapter, DMAC_CMD, DMAC_CMD_SWR_,
                                 0, 1000, 20000, 100);
        switch (DEFAULT_DMA_DESCRIPTOR_SPACING) {
        case DMA_DESCRIPTOR_SPACING_16:
                data = DMAC_CFG_MAX_DSPACE_16_;
                break;
        case DMA_DESCRIPTOR_SPACING_32:
                data = DMAC_CFG_MAX_DSPACE_32_;
                break;
        case DMA_DESCRIPTOR_SPACING_64:
                data = DMAC_CFG_MAX_DSPACE_64_;
                break;
        case DMA_DESCRIPTOR_SPACING_128:
                data = DMAC_CFG_MAX_DSPACE_128_;
                break;
        default:
                return -EPERM;
        }
        if (!(adapter->csr.flags & LAN743X_CSR_FLAG_IS_A0))
                data |= DMAC_CFG_COAL_EN_;
        data |= DMAC_CFG_CH_ARB_SEL_RX_HIGH_;
        data |= DMAC_CFG_MAX_READ_REQ_SET_(6);
        lan743x_csr_write(adapter, DMAC_CFG, data);
        data = DMAC_COAL_CFG_TIMER_LIMIT_SET_(1);
        data |= DMAC_COAL_CFG_TIMER_TX_START_;
        data |= DMAC_COAL_CFG_FLUSH_INTS_;
        data |= DMAC_COAL_CFG_INT_EXIT_COAL_;
        data |= DMAC_COAL_CFG_CSR_EXIT_COAL_;
        data |= DMAC_COAL_CFG_TX_THRES_SET_(0x0A);
        data |= DMAC_COAL_CFG_RX_THRES_SET_(0x0C);
        lan743x_csr_write(adapter, DMAC_COAL_CFG, data);
        data = DMAC_OBFF_TX_THRES_SET_(0x08);
        data |= DMAC_OBFF_RX_THRES_SET_(0x0A);
        lan743x_csr_write(adapter, DMAC_OBFF_CFG, data);
        return 0;
}

static int lan743x_dmac_tx_get_state(struct lan743x_adapter *adapter,
                                     int tx_channel)
{
        u32 dmac_cmd = 0;

        dmac_cmd = lan743x_csr_read(adapter, DMAC_CMD);
        return DMAC_CHANNEL_STATE_SET((dmac_cmd &
                                      DMAC_CMD_START_T_(tx_channel)),
                                      (dmac_cmd &
                                      DMAC_CMD_STOP_T_(tx_channel)));
}

static int lan743x_dmac_tx_wait_till_stopped(struct lan743x_adapter *adapter,
                                             int tx_channel)
{
        int timeout = 100;
        int result = 0;

        while (timeout &&
               ((result = lan743x_dmac_tx_get_state(adapter, tx_channel)) ==
               DMAC_CHANNEL_STATE_STOP_PENDING)) {
                usleep_range(1000, 20000);
                timeout--;
        }
        if (result == DMAC_CHANNEL_STATE_STOP_PENDING)
                result = -ENODEV;
        return result;
}

static int lan743x_dmac_rx_get_state(struct lan743x_adapter *adapter,
                                     int rx_channel)
{
        u32 dmac_cmd = 0;

        dmac_cmd = lan743x_csr_read(adapter, DMAC_CMD);
        return DMAC_CHANNEL_STATE_SET((dmac_cmd &
                                      DMAC_CMD_START_R_(rx_channel)),
                                      (dmac_cmd &
                                      DMAC_CMD_STOP_R_(rx_channel)));
}

static int lan743x_dmac_rx_wait_till_stopped(struct lan743x_adapter *adapter,
                                             int rx_channel)
{
        int timeout = 100;
        int result = 0;

        while (timeout &&
               ((result = lan743x_dmac_rx_get_state(adapter, rx_channel)) ==
               DMAC_CHANNEL_STATE_STOP_PENDING)) {
                usleep_range(1000, 20000);
                timeout--;
        }
        if (result == DMAC_CHANNEL_STATE_STOP_PENDING)
                result = -ENODEV;
        return result;
}

static void lan743x_tx_release_desc(struct lan743x_tx *tx,
                                    int descriptor_index, bool cleanup)
{
        struct lan743x_tx_buffer_info *buffer_info = NULL;
        struct lan743x_tx_descriptor *descriptor = NULL;
        u32 descriptor_type = 0;
        bool ignore_sync;

        descriptor = &tx->ring_cpu_ptr[descriptor_index];
        buffer_info = &tx->buffer_info[descriptor_index];
        if (!(buffer_info->flags & TX_BUFFER_INFO_FLAG_ACTIVE))
                goto done;

        descriptor_type = le32_to_cpu(descriptor->data0) &
                          TX_DESC_DATA0_DTYPE_MASK_;
        if (descriptor_type == TX_DESC_DATA0_DTYPE_DATA_)
                goto clean_up_data_descriptor;
        else
                goto clear_active;

clean_up_data_descriptor:
        if (buffer_info->dma_ptr) {
                if (buffer_info->flags &
                    TX_BUFFER_INFO_FLAG_SKB_FRAGMENT) {
                        dma_unmap_page(&tx->adapter->pdev->dev,
                                       buffer_info->dma_ptr,
                                       buffer_info->buffer_length,
                                       DMA_TO_DEVICE);
                } else {
                        dma_unmap_single(&tx->adapter->pdev->dev,
                                         buffer_info->dma_ptr,
                                         buffer_info->buffer_length,
                                         DMA_TO_DEVICE);
                }
                buffer_info->dma_ptr = 0;
                buffer_info->buffer_length = 0;
        }
        if (!buffer_info->skb)
                goto clear_active;

        if (!(buffer_info->flags & TX_BUFFER_INFO_FLAG_TIMESTAMP_REQUESTED)) {
                dev_kfree_skb_any(buffer_info->skb);
                goto clear_skb;
        }

        if (cleanup) {
                lan743x_ptp_unrequest_tx_timestamp(tx->adapter);
                dev_kfree_skb_any(buffer_info->skb);
        } else {
                ignore_sync = (buffer_info->flags &
                               TX_BUFFER_INFO_FLAG_IGNORE_SYNC) != 0;
                lan743x_ptp_tx_timestamp_skb(tx->adapter,
                                             buffer_info->skb, ignore_sync);
        }

clear_skb:
        buffer_info->skb = NULL;

clear_active:
        buffer_info->flags &= ~TX_BUFFER_INFO_FLAG_ACTIVE;

done:
        memset(buffer_info, 0, sizeof(*buffer_info));
        memset(descriptor, 0, sizeof(*descriptor));
}

static int lan743x_tx_next_index(struct lan743x_tx *tx, int index)
{
        return ((++index) % tx->ring_size);
}

static void lan743x_tx_release_completed_descriptors(struct lan743x_tx *tx)
{
        while (le32_to_cpu(*tx->head_cpu_ptr) != (tx->last_head)) {
                lan743x_tx_release_desc(tx, tx->last_head, false);
                tx->last_head = lan743x_tx_next_index(tx, tx->last_head);
        }
}

static void lan743x_tx_release_all_descriptors(struct lan743x_tx *tx)
{
        u32 original_head = 0;

        original_head = tx->last_head;
        do {
                lan743x_tx_release_desc(tx, tx->last_head, true);
                tx->last_head = lan743x_tx_next_index(tx, tx->last_head);
        } while (tx->last_head != original_head);
        memset(tx->ring_cpu_ptr, 0,
               sizeof(*tx->ring_cpu_ptr) * (tx->ring_size));
        memset(tx->buffer_info, 0,
               sizeof(*tx->buffer_info) * (tx->ring_size));
}

static int lan743x_tx_get_desc_cnt(struct lan743x_tx *tx,
                                   struct sk_buff *skb)
{
        int result = 1; /* 1 for the main skb buffer */
        int nr_frags = 0;

        if (skb_is_gso(skb))
                result++; /* requires an extension descriptor */
        nr_frags = skb_shinfo(skb)->nr_frags;
        result += nr_frags; /* 1 for each fragment buffer */
        return result;
}

static int lan743x_tx_get_avail_desc(struct lan743x_tx *tx)
{
        int last_head = tx->last_head;
        int last_tail = tx->last_tail;

        if (last_tail >= last_head)
                return tx->ring_size - last_tail + last_head - 1;
        else
                return last_head - last_tail - 1;
}

void lan743x_tx_set_timestamping_mode(struct lan743x_tx *tx,
                                      bool enable_timestamping,
                                      bool enable_onestep_sync)
{
        if (enable_timestamping)
                tx->ts_flags |= TX_TS_FLAG_TIMESTAMPING_ENABLED;
        else
                tx->ts_flags &= ~TX_TS_FLAG_TIMESTAMPING_ENABLED;
        if (enable_onestep_sync)
                tx->ts_flags |= TX_TS_FLAG_ONE_STEP_SYNC;
        else
                tx->ts_flags &= ~TX_TS_FLAG_ONE_STEP_SYNC;
}

static int lan743x_tx_frame_start(struct lan743x_tx *tx,
                                  unsigned char *first_buffer,
                                  unsigned int first_buffer_length,
                                  unsigned int frame_length,
                                  bool time_stamp,
                                  bool check_sum)
{
        /* called only from within lan743x_tx_xmit_frame.
         * assuming tx->ring_lock has already been acquired.
         */
        struct lan743x_tx_descriptor *tx_descriptor = NULL;
        struct lan743x_tx_buffer_info *buffer_info = NULL;
        struct lan743x_adapter *adapter = tx->adapter;
        struct device *dev = &adapter->pdev->dev;
        dma_addr_t dma_ptr;

        tx->frame_flags |= TX_FRAME_FLAG_IN_PROGRESS;
        tx->frame_first = tx->last_tail;
        tx->frame_tail = tx->frame_first;

        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
        buffer_info = &tx->buffer_info[tx->frame_tail];
        dma_ptr = dma_map_single(dev, first_buffer, first_buffer_length,
                                 DMA_TO_DEVICE);
        if (dma_mapping_error(dev, dma_ptr))
                return -ENOMEM;

        tx_descriptor->data1 = cpu_to_le32(DMA_ADDR_LOW32(dma_ptr));
        tx_descriptor->data2 = cpu_to_le32(DMA_ADDR_HIGH32(dma_ptr));
        tx_descriptor->data3 = cpu_to_le32((frame_length << 16) &
                TX_DESC_DATA3_FRAME_LENGTH_MSS_MASK_);

        buffer_info->skb = NULL;
        buffer_info->dma_ptr = dma_ptr;
        buffer_info->buffer_length = first_buffer_length;
        buffer_info->flags |= TX_BUFFER_INFO_FLAG_ACTIVE;

        tx->frame_data0 = (first_buffer_length &
                TX_DESC_DATA0_BUF_LENGTH_MASK_) |
                TX_DESC_DATA0_DTYPE_DATA_ |
                TX_DESC_DATA0_FS_ |
                TX_DESC_DATA0_FCS_;
        if (time_stamp)
                tx->frame_data0 |= TX_DESC_DATA0_TSE_;

        if (check_sum)
                tx->frame_data0 |= TX_DESC_DATA0_ICE_ |
                                   TX_DESC_DATA0_IPE_ |
                                   TX_DESC_DATA0_TPE_;

        /* data0 will be programmed in one of other frame assembler functions */
        return 0;
}

static void lan743x_tx_frame_add_lso(struct lan743x_tx *tx,
                                     unsigned int frame_length,
                                     int nr_frags)
{
        /* called only from within lan743x_tx_xmit_frame.
         * assuming tx->ring_lock has already been acquired.
         */
        struct lan743x_tx_descriptor *tx_descriptor = NULL;
        struct lan743x_tx_buffer_info *buffer_info = NULL;

        /* wrap up previous descriptor */
        tx->frame_data0 |= TX_DESC_DATA0_EXT_;
        if (nr_frags <= 0) {
                tx->frame_data0 |= TX_DESC_DATA0_LS_;
                tx->frame_data0 |= TX_DESC_DATA0_IOC_;
        }
        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
        tx_descriptor->data0 = cpu_to_le32(tx->frame_data0);

        /* move to next descriptor */
        tx->frame_tail = lan743x_tx_next_index(tx, tx->frame_tail);
        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
        buffer_info = &tx->buffer_info[tx->frame_tail];

        /* add extension descriptor */
        tx_descriptor->data1 = 0;
        tx_descriptor->data2 = 0;
        tx_descriptor->data3 = 0;

        buffer_info->skb = NULL;
        buffer_info->dma_ptr = 0;
        buffer_info->buffer_length = 0;
        buffer_info->flags |= TX_BUFFER_INFO_FLAG_ACTIVE;

        tx->frame_data0 = (frame_length & TX_DESC_DATA0_EXT_PAY_LENGTH_MASK_) |
                          TX_DESC_DATA0_DTYPE_EXT_ |
                          TX_DESC_DATA0_EXT_LSO_;

        /* data0 will be programmed in one of other frame assembler functions */
}

static int lan743x_tx_frame_add_fragment(struct lan743x_tx *tx,
                                         const skb_frag_t *fragment,
                                         unsigned int frame_length)
{
        /* called only from within lan743x_tx_xmit_frame
         * assuming tx->ring_lock has already been acquired
         */
        struct lan743x_tx_descriptor *tx_descriptor = NULL;
        struct lan743x_tx_buffer_info *buffer_info = NULL;
        struct lan743x_adapter *adapter = tx->adapter;
        struct device *dev = &adapter->pdev->dev;
        unsigned int fragment_length = 0;
        dma_addr_t dma_ptr;

        fragment_length = skb_frag_size(fragment);
        if (!fragment_length)
                return 0;

        /* wrap up previous descriptor */
        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
        tx_descriptor->data0 = cpu_to_le32(tx->frame_data0);

        /* move to next descriptor */
        tx->frame_tail = lan743x_tx_next_index(tx, tx->frame_tail);
        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
        buffer_info = &tx->buffer_info[tx->frame_tail];
        dma_ptr = skb_frag_dma_map(dev, fragment,
                                   0, fragment_length,
                                   DMA_TO_DEVICE);
        if (dma_mapping_error(dev, dma_ptr)) {
                int desc_index;

                /* cleanup all previously setup descriptors */
                desc_index = tx->frame_first;
                while (desc_index != tx->frame_tail) {
                        lan743x_tx_release_desc(tx, desc_index, true);
                        desc_index = lan743x_tx_next_index(tx, desc_index);
                }
                dma_wmb();
                tx->frame_flags &= ~TX_FRAME_FLAG_IN_PROGRESS;
                tx->frame_first = 0;
                tx->frame_data0 = 0;
                tx->frame_tail = 0;
                return -ENOMEM;
        }

        tx_descriptor->data1 = cpu_to_le32(DMA_ADDR_LOW32(dma_ptr));
        tx_descriptor->data2 = cpu_to_le32(DMA_ADDR_HIGH32(dma_ptr));
        tx_descriptor->data3 = cpu_to_le32((frame_length << 16) &
                               TX_DESC_DATA3_FRAME_LENGTH_MSS_MASK_);

        buffer_info->skb = NULL;
        buffer_info->dma_ptr = dma_ptr;
        buffer_info->buffer_length = fragment_length;
        buffer_info->flags |= TX_BUFFER_INFO_FLAG_ACTIVE;
        buffer_info->flags |= TX_BUFFER_INFO_FLAG_SKB_FRAGMENT;

        tx->frame_data0 = (fragment_length & TX_DESC_DATA0_BUF_LENGTH_MASK_) |
                          TX_DESC_DATA0_DTYPE_DATA_ |
                          TX_DESC_DATA0_FCS_;

        /* data0 will be programmed in one of other frame assembler functions */
        return 0;
}

static void lan743x_tx_frame_end(struct lan743x_tx *tx,
                                 struct sk_buff *skb,
                                 bool time_stamp,
                                 bool ignore_sync)
{
        /* called only from within lan743x_tx_xmit_frame
         * assuming tx->ring_lock has already been acquired
         */
        struct lan743x_tx_descriptor *tx_descriptor = NULL;
        struct lan743x_tx_buffer_info *buffer_info = NULL;
        struct lan743x_adapter *adapter = tx->adapter;
        u32 tx_tail_flags = 0;

        /* wrap up previous descriptor */
        if ((tx->frame_data0 & TX_DESC_DATA0_DTYPE_MASK_) ==
            TX_DESC_DATA0_DTYPE_DATA_) {
                tx->frame_data0 |= TX_DESC_DATA0_LS_;
                tx->frame_data0 |= TX_DESC_DATA0_IOC_;
        }

        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
        buffer_info = &tx->buffer_info[tx->frame_tail];
        buffer_info->skb = skb;
        if (time_stamp)
                buffer_info->flags |= TX_BUFFER_INFO_FLAG_TIMESTAMP_REQUESTED;
        if (ignore_sync)
                buffer_info->flags |= TX_BUFFER_INFO_FLAG_IGNORE_SYNC;

        tx_descriptor->data0 = cpu_to_le32(tx->frame_data0);
        tx->frame_tail = lan743x_tx_next_index(tx, tx->frame_tail);
        tx->last_tail = tx->frame_tail;

        dma_wmb();

        if (tx->vector_flags & LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_SET)
                tx_tail_flags |= TX_TAIL_SET_TOP_INT_VEC_EN_;
        if (tx->vector_flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_SET)
                tx_tail_flags |= TX_TAIL_SET_DMAC_INT_EN_ |
                TX_TAIL_SET_TOP_INT_EN_;

        lan743x_csr_write(adapter, TX_TAIL(tx->channel_number),
                          tx_tail_flags | tx->frame_tail);
        tx->frame_flags &= ~TX_FRAME_FLAG_IN_PROGRESS;
}

static netdev_tx_t lan743x_tx_xmit_frame(struct lan743x_tx *tx,
                                         struct sk_buff *skb)
{
        int required_number_of_descriptors = 0;
        unsigned int start_frame_length = 0;
        unsigned int frame_length = 0;
        unsigned int head_length = 0;
        unsigned long irq_flags = 0;
        bool do_timestamp = false;
        bool ignore_sync = false;
        int nr_frags = 0;
        bool gso = false;
        int j;

        required_number_of_descriptors = lan743x_tx_get_desc_cnt(tx, skb);

        spin_lock_irqsave(&tx->ring_lock, irq_flags);
        if (required_number_of_descriptors >
                lan743x_tx_get_avail_desc(tx)) {
                if (required_number_of_descriptors > (tx->ring_size - 1)) {
                        dev_kfree_skb_irq(skb);
                } else {
                        /* save to overflow buffer */
                        tx->overflow_skb = skb;
                        netif_stop_queue(tx->adapter->netdev);
                }
                goto unlock;
        }

        /* space available, transmit skb  */
        if ((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
            (tx->ts_flags & TX_TS_FLAG_TIMESTAMPING_ENABLED) &&
            (lan743x_ptp_request_tx_timestamp(tx->adapter))) {
                skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
                do_timestamp = true;
                if (tx->ts_flags & TX_TS_FLAG_ONE_STEP_SYNC)
                        ignore_sync = true;
        }
        head_length = skb_headlen(skb);
        frame_length = skb_pagelen(skb);
        nr_frags = skb_shinfo(skb)->nr_frags;
        start_frame_length = frame_length;
        gso = skb_is_gso(skb);
        if (gso) {
                start_frame_length = max(skb_shinfo(skb)->gso_size,
                                         (unsigned short)8);
        }

        if (lan743x_tx_frame_start(tx,
                                   skb->data, head_length,
                                   start_frame_length,
                                   do_timestamp,
                                   skb->ip_summed == CHECKSUM_PARTIAL)) {
                dev_kfree_skb_irq(skb);
                goto unlock;
        }

        if (gso)
                lan743x_tx_frame_add_lso(tx, frame_length, nr_frags);

        if (nr_frags <= 0)
                goto finish;

        for (j = 0; j < nr_frags; j++) {
                const skb_frag_t *frag = &(skb_shinfo(skb)->frags[j]);

                if (lan743x_tx_frame_add_fragment(tx, frag, frame_length)) {
                        /* upon error no need to call
                         *      lan743x_tx_frame_end
                         * frame assembler clean up was performed inside
                         *      lan743x_tx_frame_add_fragment
                         */
                        dev_kfree_skb_irq(skb);
                        goto unlock;
                }
        }

finish:
        lan743x_tx_frame_end(tx, skb, do_timestamp, ignore_sync);

unlock:
        spin_unlock_irqrestore(&tx->ring_lock, irq_flags);
        return NETDEV_TX_OK;
}

static int lan743x_tx_napi_poll(struct napi_struct *napi, int weight)
{
        struct lan743x_tx *tx = container_of(napi, struct lan743x_tx, napi);
        struct lan743x_adapter *adapter = tx->adapter;
        bool start_transmitter = false;
        unsigned long irq_flags = 0;
        u32 ioc_bit = 0;

        ioc_bit = DMAC_INT_BIT_TX_IOC_(tx->channel_number);
        lan743x_csr_read(adapter, DMAC_INT_STS);
        if (tx->vector_flags & LAN743X_VECTOR_FLAG_SOURCE_STATUS_W2C)
                lan743x_csr_write(adapter, DMAC_INT_STS, ioc_bit);
        spin_lock_irqsave(&tx->ring_lock, irq_flags);

        /* clean up tx ring */
        lan743x_tx_release_completed_descriptors(tx);
        if (netif_queue_stopped(adapter->netdev)) {
                if (tx->overflow_skb) {
                        if (lan743x_tx_get_desc_cnt(tx, tx->overflow_skb) <=
                                lan743x_tx_get_avail_desc(tx))
                                start_transmitter = true;
                } else {
                        netif_wake_queue(adapter->netdev);
                }
        }
        spin_unlock_irqrestore(&tx->ring_lock, irq_flags);

        if (start_transmitter) {
                /* space is now available, transmit overflow skb */
                lan743x_tx_xmit_frame(tx, tx->overflow_skb);
                tx->overflow_skb = NULL;
                netif_wake_queue(adapter->netdev);
        }

        if (!napi_complete(napi))
                goto done;

        /* enable isr */
        lan743x_csr_write(adapter, INT_EN_SET,
                          INT_BIT_DMA_TX_(tx->channel_number));
        lan743x_csr_read(adapter, INT_STS);

done:
        return 0;
}

static void lan743x_tx_ring_cleanup(struct lan743x_tx *tx)
{
        if (tx->head_cpu_ptr) {
                dma_free_coherent(&tx->adapter->pdev->dev,
                                  sizeof(*tx->head_cpu_ptr), tx->head_cpu_ptr,
                                  tx->head_dma_ptr);
                tx->head_cpu_ptr = NULL;
                tx->head_dma_ptr = 0;
        }
        kfree(tx->buffer_info);
        tx->buffer_info = NULL;

        if (tx->ring_cpu_ptr) {
                dma_free_coherent(&tx->adapter->pdev->dev,
                                  tx->ring_allocation_size, tx->ring_cpu_ptr,
                                  tx->ring_dma_ptr);
                tx->ring_allocation_size = 0;
                tx->ring_cpu_ptr = NULL;
                tx->ring_dma_ptr = 0;
        }
        tx->ring_size = 0;
}

static int lan743x_tx_ring_init(struct lan743x_tx *tx)
{
        size_t ring_allocation_size = 0;
        void *cpu_ptr = NULL;
        dma_addr_t dma_ptr;
        int ret = -ENOMEM;

        tx->ring_size = LAN743X_TX_RING_SIZE;
        if (tx->ring_size & ~TX_CFG_B_TX_RING_LEN_MASK_) {
                ret = -EINVAL;
                goto cleanup;
        }
        ring_allocation_size = ALIGN(tx->ring_size *
                                     sizeof(struct lan743x_tx_descriptor),
                                     PAGE_SIZE);
        dma_ptr = 0;
        cpu_ptr = dma_alloc_coherent(&tx->adapter->pdev->dev,
                                     ring_allocation_size, &dma_ptr, GFP_KERNEL);
        if (!cpu_ptr) {
                ret = -ENOMEM;
                goto cleanup;
        }

        tx->ring_allocation_size = ring_allocation_size;
        tx->ring_cpu_ptr = (struct lan743x_tx_descriptor *)cpu_ptr;
        tx->ring_dma_ptr = dma_ptr;

        cpu_ptr = kcalloc(tx->ring_size, sizeof(*tx->buffer_info), GFP_KERNEL);
        if (!cpu_ptr) {
                ret = -ENOMEM;
                goto cleanup;
        }
        tx->buffer_info = (struct lan743x_tx_buffer_info *)cpu_ptr;
        dma_ptr = 0;
        cpu_ptr = dma_alloc_coherent(&tx->adapter->pdev->dev,
                                     sizeof(*tx->head_cpu_ptr), &dma_ptr,
                                     GFP_KERNEL);
        if (!cpu_ptr) {
                ret = -ENOMEM;
                goto cleanup;
        }

        tx->head_cpu_ptr = cpu_ptr;
        tx->head_dma_ptr = dma_ptr;
        if (tx->head_dma_ptr & 0x3) {
                ret = -ENOMEM;
                goto cleanup;
        }

        return 0;

cleanup:
        lan743x_tx_ring_cleanup(tx);
        return ret;
}

static void lan743x_tx_close(struct lan743x_tx *tx)
{
        struct lan743x_adapter *adapter = tx->adapter;

        lan743x_csr_write(adapter,
                          DMAC_CMD,
                          DMAC_CMD_STOP_T_(tx->channel_number));
        lan743x_dmac_tx_wait_till_stopped(adapter, tx->channel_number);

        lan743x_csr_write(adapter,
                          DMAC_INT_EN_CLR,
                          DMAC_INT_BIT_TX_IOC_(tx->channel_number));
        lan743x_csr_write(adapter, INT_EN_CLR,
                          INT_BIT_DMA_TX_(tx->channel_number));
        napi_disable(&tx->napi);
        netif_napi_del(&tx->napi);

        lan743x_csr_write(adapter, FCT_TX_CTL,
                          FCT_TX_CTL_DIS_(tx->channel_number));
        lan743x_csr_wait_for_bit(adapter, FCT_TX_CTL,
                                 FCT_TX_CTL_EN_(tx->channel_number),
                                 0, 1000, 20000, 100);

        lan743x_tx_release_all_descriptors(tx);

        if (tx->overflow_skb) {
                dev_kfree_skb(tx->overflow_skb);
                tx->overflow_skb = NULL;
        }

        lan743x_tx_ring_cleanup(tx);
}

static int lan743x_tx_open(struct lan743x_tx *tx)
{
        struct lan743x_adapter *adapter = NULL;
        u32 data = 0;
        int ret;

        adapter = tx->adapter;
        ret = lan743x_tx_ring_init(tx);
        if (ret)
                return ret;

        /* initialize fifo */
        lan743x_csr_write(adapter, FCT_TX_CTL,
                          FCT_TX_CTL_RESET_(tx->channel_number));
        lan743x_csr_wait_for_bit(adapter, FCT_TX_CTL,
                                 FCT_TX_CTL_RESET_(tx->channel_number),
                                 0, 1000, 20000, 100);

        /* enable fifo */
        lan743x_csr_write(adapter, FCT_TX_CTL,
                          FCT_TX_CTL_EN_(tx->channel_number));

        /* reset tx channel */
        lan743x_csr_write(adapter, DMAC_CMD,
                          DMAC_CMD_TX_SWR_(tx->channel_number));
        lan743x_csr_wait_for_bit(adapter, DMAC_CMD,
                                 DMAC_CMD_TX_SWR_(tx->channel_number),
                                 0, 1000, 20000, 100);

        /* Write TX_BASE_ADDR */
        lan743x_csr_write(adapter,
                          TX_BASE_ADDRH(tx->channel_number),
                          DMA_ADDR_HIGH32(tx->ring_dma_ptr));
        lan743x_csr_write(adapter,
                          TX_BASE_ADDRL(tx->channel_number),
                          DMA_ADDR_LOW32(tx->ring_dma_ptr));

        /* Write TX_CFG_B */
        data = lan743x_csr_read(adapter, TX_CFG_B(tx->channel_number));
        data &= ~TX_CFG_B_TX_RING_LEN_MASK_;
        data |= ((tx->ring_size) & TX_CFG_B_TX_RING_LEN_MASK_);
        if (!(adapter->csr.flags & LAN743X_CSR_FLAG_IS_A0))
                data |= TX_CFG_B_TDMABL_512_;
        lan743x_csr_write(adapter, TX_CFG_B(tx->channel_number), data);

        /* Write TX_CFG_A */
        data = TX_CFG_A_TX_TMR_HPWB_SEL_IOC_ | TX_CFG_A_TX_HP_WB_EN_;
        if (!(adapter->csr.flags & LAN743X_CSR_FLAG_IS_A0)) {
                data |= TX_CFG_A_TX_HP_WB_ON_INT_TMR_;
                data |= TX_CFG_A_TX_PF_THRES_SET_(0x10);
                data |= TX_CFG_A_TX_PF_PRI_THRES_SET_(0x04);
                data |= TX_CFG_A_TX_HP_WB_THRES_SET_(0x07);
        }
        lan743x_csr_write(adapter, TX_CFG_A(tx->channel_number), data);

        /* Write TX_HEAD_WRITEBACK_ADDR */
        lan743x_csr_write(adapter,
                          TX_HEAD_WRITEBACK_ADDRH(tx->channel_number),
                          DMA_ADDR_HIGH32(tx->head_dma_ptr));
        lan743x_csr_write(adapter,
                          TX_HEAD_WRITEBACK_ADDRL(tx->channel_number),
                          DMA_ADDR_LOW32(tx->head_dma_ptr));

        /* set last head */
        tx->last_head = lan743x_csr_read(adapter, TX_HEAD(tx->channel_number));

        /* write TX_TAIL */
        tx->last_tail = 0;
        lan743x_csr_write(adapter, TX_TAIL(tx->channel_number),
                          (u32)(tx->last_tail));
        tx->vector_flags = lan743x_intr_get_vector_flags(adapter,
                                                         INT_BIT_DMA_TX_
                                                         (tx->channel_number));
        netif_tx_napi_add(adapter->netdev,
                          &tx->napi, lan743x_tx_napi_poll,
                          tx->ring_size - 1);
        napi_enable(&tx->napi);

        data = 0;
        if (tx->vector_flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_CLEAR)
                data |= TX_CFG_C_TX_TOP_INT_EN_AUTO_CLR_;
        if (tx->vector_flags & LAN743X_VECTOR_FLAG_SOURCE_STATUS_AUTO_CLEAR)
                data |= TX_CFG_C_TX_DMA_INT_STS_AUTO_CLR_;
        if (tx->vector_flags & LAN743X_VECTOR_FLAG_SOURCE_STATUS_R2C)
                data |= TX_CFG_C_TX_INT_STS_R2C_MODE_MASK_;
        if (tx->vector_flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_R2C)
                data |= TX_CFG_C_TX_INT_EN_R2C_;
        lan743x_csr_write(adapter, TX_CFG_C(tx->channel_number), data);

        if (!(tx->vector_flags & LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_SET))
                lan743x_csr_write(adapter, INT_EN_SET,
                                  INT_BIT_DMA_TX_(tx->channel_number));
        lan743x_csr_write(adapter, DMAC_INT_EN_SET,
                          DMAC_INT_BIT_TX_IOC_(tx->channel_number));

        /*  start dmac channel */
        lan743x_csr_write(adapter, DMAC_CMD,
                          DMAC_CMD_START_T_(tx->channel_number));
        return 0;
}

static int lan743x_rx_next_index(struct lan743x_rx *rx, int index)
{
        return ((++index) % rx->ring_size);
}

static void lan743x_rx_update_tail(struct lan743x_rx *rx, int index)
{
        /* update the tail once per 8 descriptors */
        if ((index & 7) == 7)
                lan743x_csr_write(rx->adapter, RX_TAIL(rx->channel_number),
                                  index);
}

static int lan743x_rx_init_ring_element(struct lan743x_rx *rx, int index)
{
        struct net_device *netdev = rx->adapter->netdev;
        struct device *dev = &rx->adapter->pdev->dev;
        struct lan743x_rx_buffer_info *buffer_info;
        unsigned int buffer_length, used_length;
        struct lan743x_rx_descriptor *descriptor;
        struct sk_buff *skb;
        dma_addr_t dma_ptr;

        buffer_length = netdev->mtu + ETH_HLEN + ETH_FCS_LEN + RX_HEAD_PADDING;

        descriptor = &rx->ring_cpu_ptr[index];
        buffer_info = &rx->buffer_info[index];
        skb = __netdev_alloc_skb(netdev, buffer_length, GFP_ATOMIC | GFP_DMA);
        if (!skb)
                return -ENOMEM;
        dma_ptr = dma_map_single(dev, skb->data, buffer_length, DMA_FROM_DEVICE);
        if (dma_mapping_error(dev, dma_ptr)) {
                dev_kfree_skb_any(skb);
                return -ENOMEM;
        }
        if (buffer_info->dma_ptr) {
                /* sync used area of buffer only */
                if (le32_to_cpu(descriptor->data0) & RX_DESC_DATA0_LS_)
                        /* frame length is valid only if LS bit is set.
                         * it's a safe upper bound for the used area in this
                         * buffer.
                         */
                        used_length = min(RX_DESC_DATA0_FRAME_LENGTH_GET_
                                          (le32_to_cpu(descriptor->data0)),
                                          buffer_info->buffer_length);
                else
                        used_length = buffer_info->buffer_length;
                dma_sync_single_for_cpu(dev, buffer_info->dma_ptr,
                                        used_length,
                                        DMA_FROM_DEVICE);
                dma_unmap_single_attrs(dev, buffer_info->dma_ptr,
                                       buffer_info->buffer_length,
                                       DMA_FROM_DEVICE,
                                       DMA_ATTR_SKIP_CPU_SYNC);
        }

        buffer_info->skb = skb;
        buffer_info->dma_ptr = dma_ptr;
        buffer_info->buffer_length = buffer_length;
        descriptor->data1 = cpu_to_le32(DMA_ADDR_LOW32(buffer_info->dma_ptr));
        descriptor->data2 = cpu_to_le32(DMA_ADDR_HIGH32(buffer_info->dma_ptr));
        descriptor->data3 = 0;
        descriptor->data0 = cpu_to_le32((RX_DESC_DATA0_OWN_ |
                            (buffer_length & RX_DESC_DATA0_BUF_LENGTH_MASK_)));
        lan743x_rx_update_tail(rx, index);

        return 0;
}

static void lan743x_rx_reuse_ring_element(struct lan743x_rx *rx, int index)
{
        struct lan743x_rx_buffer_info *buffer_info;
        struct lan743x_rx_descriptor *descriptor;

        descriptor = &rx->ring_cpu_ptr[index];
        buffer_info = &rx->buffer_info[index];