/*  Synopsys DWC Ethernet Quality-of-Service v4.10a linux driver
 *
 *  This is a driver for the Synopsys DWC Ethernet QoS IP version 4.10a (GMAC).
 *  This version introduced a lot of changes which breaks backwards
 *  compatibility the non-QoS IP from Synopsys (used in the ST Micro drivers).
 *  Some fields differ between version 4.00a and 4.10a, mainly the interrupt
 *  bit fields. The driver could be made compatible with 4.00, if all relevant
 *  HW erratas are handled.
 *
 *  The GMAC is highly configurable at synthesis time. This driver has been
 *  developed for a subset of the total available feature set. Currently
 *  it supports:
 *  - TSO
 *  - Checksum offload for RX and TX.
 *  - Energy efficient ethernet.
 *  - GMII phy interface.
 *  - The statistics module.
 *  - Single RX and TX queue.
 *
 *  Copyright (C) 2015 Axis Communications AB.
 *
 *  This program is free software; you can redistribute it and/or modify it
 *  under the terms and conditions of the GNU General Public License,
 *  version 2, as published by the Free Software Foundation.
 */

#include <linux/clk.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ethtool.h>
#include <linux/stat.h>
#include <linux/types.h>

#include <linux/types.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/mm.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/platform_device.h>

#include <linux/phy.h>
#include <linux/mii.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/vmalloc.h>
#include <linux/version.h>

#include <linux/device.h>
#include <linux/bitrev.h>
#include <linux/crc32.h>

#include <linux/of.h>
#include <linux/interrupt.h>
#include <linux/clocksource.h>
#include <linux/net_tstamp.h>
#include <linux/pm_runtime.h>
#include <linux/of_net.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/timer.h>
#include <linux/tcp.h>

#define DRIVER_NAME                     "dwceqos"
#define DRIVER_DESCRIPTION              "Synopsys DWC Ethernet QoS driver"
#define DRIVER_VERSION                  "0.9"

#define DWCEQOS_MSG_DEFAULT     (NETIF_MSG_DRV | NETIF_MSG_PROBE | \
        NETIF_MSG_LINK | NETIF_MSG_IFDOWN | NETIF_MSG_IFUP)

#define DWCEQOS_TX_TIMEOUT 5 /* Seconds */

#define DWCEQOS_LPI_TIMER_MIN      8
#define DWCEQOS_LPI_TIMER_MAX      ((1 << 20) - 1)

#define DWCEQOS_RX_BUF_SIZE 2048

#define DWCEQOS_RX_DCNT 256
#define DWCEQOS_TX_DCNT 256

#define DWCEQOS_HASH_TABLE_SIZE 64

/* The size field in the DMA descriptor is 14 bits */
#define BYTES_PER_DMA_DESC 16376

/* Hardware registers */
#define START_MAC_REG_OFFSET    0x0000
#define MAX_MAC_REG_OFFSET      0x0bd0
#define START_MTL_REG_OFFSET    0x0c00
#define MAX_MTL_REG_OFFSET      0x0d7c
#define START_DMA_REG_OFFSET    0x1000
#define MAX_DMA_REG_OFFSET      0x117C

#define REG_SPACE_SIZE          0x1800

/* DMA */
#define REG_DWCEQOS_DMA_MODE             0x1000
#define REG_DWCEQOS_DMA_SYSBUS_MODE      0x1004
#define REG_DWCEQOS_DMA_IS               0x1008
#define REG_DWCEQOS_DMA_DEBUG_ST0        0x100c

/* DMA channel registers */
#define REG_DWCEQOS_DMA_CH0_CTRL         0x1100
#define REG_DWCEQOS_DMA_CH0_TX_CTRL      0x1104
#define REG_DWCEQOS_DMA_CH0_RX_CTRL      0x1108
#define REG_DWCEQOS_DMA_CH0_TXDESC_LIST  0x1114
#define REG_DWCEQOS_DMA_CH0_RXDESC_LIST  0x111c
#define REG_DWCEQOS_DMA_CH0_TXDESC_TAIL  0x1120
#define REG_DWCEQOS_DMA_CH0_RXDESC_TAIL  0x1128
#define REG_DWCEQOS_DMA_CH0_TXDESC_LEN   0x112c
#define REG_DWCEQOS_DMA_CH0_RXDESC_LEN   0x1130
#define REG_DWCEQOS_DMA_CH0_IE           0x1134
#define REG_DWCEQOS_DMA_CH0_CUR_TXDESC   0x1144
#define REG_DWCEQOS_DMA_CH0_CUR_RXDESC   0x114c
#define REG_DWCEQOS_DMA_CH0_CUR_TXBUF    0x1154
#define REG_DWCEQOS_DMA_CH0_CUR_RXBUG    0x115c
#define REG_DWCEQOS_DMA_CH0_STA          0x1160

#define DWCEQOS_DMA_MODE_TXPR            BIT(11)
#define DWCEQOS_DMA_MODE_DA              BIT(1)

#define DWCEQOS_DMA_SYSBUS_MODE_EN_LPI   BIT(31)
#define DWCEQOS_DMA_SYSBUS_MODE_FB       BIT(0)
#define DWCEQOS_DMA_SYSBUS_MODE_AAL      BIT(12)

#define DWCEQOS_DMA_SYSBUS_MODE_RD_OSR_LIMIT(x) \
        (((x) << 16) & 0x000F0000)
#define DWCEQOS_DMA_SYSBUS_MODE_RD_OSR_LIMIT_DEFAULT    3
#define DWCEQOS_DMA_SYSBUS_MODE_RD_OSR_LIMIT_MASK       GENMASK(19, 16)

#define DWCEQOS_DMA_SYSBUS_MODE_WR_OSR_LIMIT(x) \
        (((x) << 24) & 0x0F000000)
#define DWCEQOS_DMA_SYSBUS_MODE_WR_OSR_LIMIT_DEFAULT    3
#define DWCEQOS_DMA_SYSBUS_MODE_WR_OSR_LIMIT_MASK       GENMASK(27, 24)

#define DWCEQOS_DMA_SYSBUS_MODE_BURST_MASK GENMASK(7, 1)
#define DWCEQOS_DMA_SYSBUS_MODE_BURST(x) \
        (((x) << 1) & DWCEQOS_DMA_SYSBUS_MODE_BURST_MASK)
#define DWCEQOS_DMA_SYSBUS_MODE_BURST_DEFAULT   GENMASK(3, 1)

#define DWCEQOS_DMA_CH_CTRL_PBLX8       BIT(16)
#define DWCEQOS_DMA_CH_CTRL_DSL(x)      ((x) << 18)

#define DWCEQOS_DMA_CH_CTRL_PBL(x)       ((x) << 16)
#define DWCEQOS_DMA_CH_CTRL_START         BIT(0)
#define DWCEQOS_DMA_CH_RX_CTRL_BUFSIZE(x)   ((x) << 1)
#define DWCEQOS_DMA_CH_TX_OSP            BIT(4)
#define DWCEQOS_DMA_CH_TX_TSE            BIT(12)

#define DWCEQOS_DMA_CH0_IE_NIE           BIT(15)
#define DWCEQOS_DMA_CH0_IE_AIE           BIT(14)
#define DWCEQOS_DMA_CH0_IE_RIE           BIT(6)
#define DWCEQOS_DMA_CH0_IE_TIE           BIT(0)
#define DWCEQOS_DMA_CH0_IE_FBEE          BIT(12)
#define DWCEQOS_DMA_CH0_IE_RBUE          BIT(7)

#define DWCEQOS_DMA_IS_DC0IS             BIT(0)
#define DWCEQOS_DMA_IS_MTLIS             BIT(16)
#define DWCEQOS_DMA_IS_MACIS             BIT(17)

#define DWCEQOS_DMA_CH0_IS_TI            BIT(0)
#define DWCEQOS_DMA_CH0_IS_RI            BIT(6)
#define DWCEQOS_DMA_CH0_IS_RBU           BIT(7)
#define DWCEQOS_DMA_CH0_IS_FBE           BIT(12)
#define DWCEQOS_DMA_CH0_IS_CDE           BIT(13)
#define DWCEQOS_DMA_CH0_IS_AIS           BIT(14)

#define DWCEQOS_DMA_CH0_IS_TEB           GENMASK(18, 16)
#define DWCEQOS_DMA_CH0_IS_TX_ERR_READ   BIT(16)
#define DWCEQOS_DMA_CH0_IS_TX_ERR_DESCR  BIT(17)

#define DWCEQOS_DMA_CH0_IS_REB           GENMASK(21, 19)
#define DWCEQOS_DMA_CH0_IS_RX_ERR_READ   BIT(19)
#define DWCEQOS_DMA_CH0_IS_RX_ERR_DESCR  BIT(20)

/* DMA descriptor bits for RX normal descriptor (read format) */
#define DWCEQOS_DMA_RDES3_OWN     BIT(31)
#define DWCEQOS_DMA_RDES3_INTE    BIT(30)
#define DWCEQOS_DMA_RDES3_BUF2V   BIT(25)
#define DWCEQOS_DMA_RDES3_BUF1V   BIT(24)

/* DMA descriptor bits for RX normal descriptor (write back format) */
#define DWCEQOS_DMA_RDES1_IPCE    BIT(7)
#define DWCEQOS_DMA_RDES3_ES      BIT(15)
#define DWCEQOS_DMA_RDES3_E_JT    BIT(14)
#define DWCEQOS_DMA_RDES3_PL(x)   ((x) & 0x7fff)
#define DWCEQOS_DMA_RDES1_PT      0x00000007
#define DWCEQOS_DMA_RDES1_PT_UDP  BIT(0)
#define DWCEQOS_DMA_RDES1_PT_TCP  BIT(1)
#define DWCEQOS_DMA_RDES1_PT_ICMP 0x00000003

/* DMA descriptor bits for TX normal descriptor (read format) */
#define DWCEQOS_DMA_TDES2_IOC     BIT(31)
#define DWCEQOS_DMA_TDES3_OWN     BIT(31)
#define DWCEQOS_DMA_TDES3_CTXT    BIT(30)
#define DWCEQOS_DMA_TDES3_FD      BIT(29)
#define DWCEQOS_DMA_TDES3_LD      BIT(28)
#define DWCEQOS_DMA_TDES3_CIPH    BIT(16)
#define DWCEQOS_DMA_TDES3_CIPP    BIT(17)
#define DWCEQOS_DMA_TDES3_CA      0x00030000
#define DWCEQOS_DMA_TDES3_TSE     BIT(18)
#define DWCEQOS_DMA_DES3_THL(x)   ((x) << 19)
#define DWCEQOS_DMA_DES2_B2L(x)   ((x) << 16)

#define DWCEQOS_DMA_TDES3_TCMSSV    BIT(26)

/* DMA channel states */
#define DMA_TX_CH_STOPPED   0
#define DMA_TX_CH_SUSPENDED 6

#define DMA_GET_TX_STATE_CH0(status0) ((status0 & 0xF000) >> 12)

/* MTL */
#define REG_DWCEQOS_MTL_OPER             0x0c00
#define REG_DWCEQOS_MTL_DEBUG_ST         0x0c0c
#define REG_DWCEQOS_MTL_TXQ0_DEBUG_ST    0x0d08
#define REG_DWCEQOS_MTL_RXQ0_DEBUG_ST    0x0d38

#define REG_DWCEQOS_MTL_IS               0x0c20
#define REG_DWCEQOS_MTL_TXQ0_OPER        0x0d00
#define REG_DWCEQOS_MTL_RXQ0_OPER        0x0d30
#define REG_DWCEQOS_MTL_RXQ0_MIS_CNT     0x0d34
#define REG_DWCEQOS_MTL_RXQ0_CTRL         0x0d3c

#define REG_DWCEQOS_MTL_Q0_ISCTRL         0x0d2c

#define DWCEQOS_MTL_SCHALG_STRICT        0x00000060

#define DWCEQOS_MTL_TXQ_TXQEN            BIT(3)
#define DWCEQOS_MTL_TXQ_TSF              BIT(1)
#define DWCEQOS_MTL_TXQ_FTQ              BIT(0)
#define DWCEQOS_MTL_TXQ_TTC512           0x00000070

#define DWCEQOS_MTL_TXQ_SIZE(x)          ((((x) - 256) & 0xff00) << 8)

#define DWCEQOS_MTL_RXQ_SIZE(x)          ((((x) - 256) & 0xff00) << 12)
#define DWCEQOS_MTL_RXQ_EHFC             BIT(7)
#define DWCEQOS_MTL_RXQ_DIS_TCP_EF       BIT(6)
#define DWCEQOS_MTL_RXQ_FEP              BIT(4)
#define DWCEQOS_MTL_RXQ_FUP              BIT(3)
#define DWCEQOS_MTL_RXQ_RSF              BIT(5)
#define DWCEQOS_MTL_RXQ_RTC32            BIT(0)

/* MAC */
#define REG_DWCEQOS_MAC_CFG              0x0000
#define REG_DWCEQOS_MAC_EXT_CFG          0x0004
#define REG_DWCEQOS_MAC_PKT_FILT         0x0008
#define REG_DWCEQOS_MAC_WD_TO            0x000c
#define REG_DWCEQOS_HASTABLE_LO          0x0010
#define REG_DWCEQOS_HASTABLE_HI          0x0014
#define REG_DWCEQOS_MAC_IS               0x00b0
#define REG_DWCEQOS_MAC_IE               0x00b4
#define REG_DWCEQOS_MAC_STAT             0x00b8
#define REG_DWCEQOS_MAC_MDIO_ADDR        0x0200
#define REG_DWCEQOS_MAC_MDIO_DATA        0x0204
#define REG_DWCEQOS_MAC_MAC_ADDR0_HI     0x0300
#define REG_DWCEQOS_MAC_MAC_ADDR0_LO     0x0304
#define REG_DWCEQOS_MAC_RXQ0_CTRL0       0x00a0
#define REG_DWCEQOS_MAC_HW_FEATURE0      0x011c
#define REG_DWCEQOS_MAC_HW_FEATURE1      0x0120
#define REG_DWCEQOS_MAC_HW_FEATURE2      0x0124
#define REG_DWCEQOS_MAC_HASHTABLE_LO     0x0010
#define REG_DWCEQOS_MAC_HASHTABLE_HI     0x0014
#define REG_DWCEQOS_MAC_LPI_CTRL_STATUS  0x00d0
#define REG_DWCEQOS_MAC_LPI_TIMERS_CTRL  0x00d4
#define REG_DWCEQOS_MAC_LPI_ENTRY_TIMER  0x00d8
#define REG_DWCEQOS_MAC_1US_TIC_COUNTER  0x00dc
#define REG_DWCEQOS_MAC_RX_FLOW_CTRL     0x0090
#define REG_DWCEQOS_MAC_Q0_TX_FLOW       0x0070

#define DWCEQOS_MAC_CFG_ACS              BIT(20)
#define DWCEQOS_MAC_CFG_JD               BIT(17)
#define DWCEQOS_MAC_CFG_JE               BIT(16)
#define DWCEQOS_MAC_CFG_PS               BIT(15)
#define DWCEQOS_MAC_CFG_FES              BIT(14)
#define DWCEQOS_MAC_CFG_DM               BIT(13)
#define DWCEQOS_MAC_CFG_DO               BIT(10)
#define DWCEQOS_MAC_CFG_TE               BIT(1)
#define DWCEQOS_MAC_CFG_IPC              BIT(27)
#define DWCEQOS_MAC_CFG_RE               BIT(0)

#define DWCEQOS_ADDR_HIGH(reg)           (0x00000300 + (reg * 8))
#define DWCEQOS_ADDR_LOW(reg)            (0x00000304 + (reg * 8))

#define DWCEQOS_MAC_IS_LPI_INT           BIT(5)
#define DWCEQOS_MAC_IS_MMC_INT           BIT(8)

#define DWCEQOS_MAC_RXQ_EN               BIT(1)
#define DWCEQOS_MAC_MAC_ADDR_HI_EN       BIT(31)
#define DWCEQOS_MAC_PKT_FILT_RA          BIT(31)
#define DWCEQOS_MAC_PKT_FILT_HPF         BIT(10)
#define DWCEQOS_MAC_PKT_FILT_SAF         BIT(9)
#define DWCEQOS_MAC_PKT_FILT_SAIF        BIT(8)
#define DWCEQOS_MAC_PKT_FILT_DBF         BIT(5)
#define DWCEQOS_MAC_PKT_FILT_PM          BIT(4)
#define DWCEQOS_MAC_PKT_FILT_DAIF        BIT(3)
#define DWCEQOS_MAC_PKT_FILT_HMC         BIT(2)
#define DWCEQOS_MAC_PKT_FILT_HUC         BIT(1)
#define DWCEQOS_MAC_PKT_FILT_PR          BIT(0)

#define DWCEQOS_MAC_MDIO_ADDR_CR(x)      (((x & 15)) << 8)
#define DWCEQOS_MAC_MDIO_ADDR_CR_20      2
#define DWCEQOS_MAC_MDIO_ADDR_CR_35      3
#define DWCEQOS_MAC_MDIO_ADDR_CR_60      0
#define DWCEQOS_MAC_MDIO_ADDR_CR_100     1
#define DWCEQOS_MAC_MDIO_ADDR_CR_150     4
#define DWCEQOS_MAC_MDIO_ADDR_CR_250     5
#define DWCEQOS_MAC_MDIO_ADDR_GOC_READ   0x0000000c
#define DWCEQOS_MAC_MDIO_ADDR_GOC_WRITE  BIT(2)
#define DWCEQOS_MAC_MDIO_ADDR_GB         BIT(0)

#define DWCEQOS_MAC_LPI_CTRL_STATUS_TLPIEN  BIT(0)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_TLPIEX  BIT(1)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_RLPIEN  BIT(2)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_RLPIEX  BIT(3)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_TLPIST  BIT(8)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_RLPIST  BIT(9)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_LPIEN   BIT(16)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_PLS     BIT(17)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_PLSEN   BIT(18)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_LIPTXA  BIT(19)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_LPITE   BIT(20)
#define DWCEQOS_MAC_LPI_CTRL_STATUS_LPITCSE BIT(21)

#define DWCEQOS_MAC_1US_TIC_COUNTER_VAL(x)  ((x) & GENMASK(11, 0))

#define DWCEQOS_LPI_CTRL_ENABLE_EEE      (DWCEQOS_MAC_LPI_CTRL_STATUS_LPITE | \
                                          DWCEQOS_MAC_LPI_CTRL_STATUS_LIPTXA | \
                                          DWCEQOS_MAC_LPI_CTRL_STATUS_LPIEN)

#define DWCEQOS_MAC_RX_FLOW_CTRL_RFE BIT(0)

#define DWCEQOS_MAC_Q0_TX_FLOW_TFE   BIT(1)
#define DWCEQOS_MAC_Q0_TX_FLOW_PT(time) ((time) << 16)
#define DWCEQOS_MAC_Q0_TX_FLOW_PLT_4_SLOTS (0 << 4)

/* Features */
#define DWCEQOS_MAC_HW_FEATURE0_RXCOESEL BIT(16)
#define DWCEQOS_MAC_HW_FEATURE0_TXCOESEL BIT(14)
#define DWCEQOS_MAC_HW_FEATURE0_HDSEL    BIT(2)
#define DWCEQOS_MAC_HW_FEATURE0_EEESEL   BIT(13)
#define DWCEQOS_MAC_HW_FEATURE0_GMIISEL  BIT(1)
#define DWCEQOS_MAC_HW_FEATURE0_MIISEL   BIT(0)

#define DWCEQOS_MAC_HW_FEATURE1_TSOEN    BIT(18)
#define DWCEQOS_MAC_HW_FEATURE1_TXFIFOSIZE(x) ((128 << ((x) & 0x7c0)) >> 6)
#define DWCEQOS_MAC_HW_FEATURE1_RXFIFOSIZE(x)  (128 << ((x) & 0x1f))

#define DWCEQOS_MAX_PERFECT_ADDRESSES(feature1) \
        (1 + (((feature1) & 0x1fc0000) >> 18))

#define DWCEQOS_MDIO_PHYADDR(x)     (((x) & 0x1f) << 21)
#define DWCEQOS_MDIO_PHYREG(x)      (((x) & 0x1f) << 16)

#define DWCEQOS_DMA_MODE_SWR            BIT(0)

#define DWCEQOS_DWCEQOS_RX_BUF_SIZE 2048

/* Mac Management Counters */
#define REG_DWCEQOS_MMC_CTRL             0x0700
#define REG_DWCEQOS_MMC_RXIRQ            0x0704
#define REG_DWCEQOS_MMC_TXIRQ            0x0708
#define REG_DWCEQOS_MMC_RXIRQMASK        0x070c
#define REG_DWCEQOS_MMC_TXIRQMASK        0x0710

#define DWCEQOS_MMC_CTRL_CNTRST          BIT(0)
#define DWCEQOS_MMC_CTRL_RSTONRD         BIT(2)

#define DWC_MMC_TXLPITRANSCNTR           0x07F0
#define DWC_MMC_TXLPIUSCNTR              0x07EC
#define DWC_MMC_TXOVERSIZE_G             0x0778
#define DWC_MMC_TXVLANPACKETS_G          0x0774
#define DWC_MMC_TXPAUSEPACKETS           0x0770
#define DWC_MMC_TXEXCESSDEF              0x076C
#define DWC_MMC_TXPACKETCOUNT_G          0x0768
#define DWC_MMC_TXOCTETCOUNT_G           0x0764
#define DWC_MMC_TXCARRIERERROR           0x0760
#define DWC_MMC_TXEXCESSCOL              0x075C
#define DWC_MMC_TXLATECOL                0x0758
#define DWC_MMC_TXDEFERRED               0x0754
#define DWC_MMC_TXMULTICOL_G             0x0750
#define DWC_MMC_TXSINGLECOL_G            0x074C
#define DWC_MMC_TXUNDERFLOWERROR         0x0748
#define DWC_MMC_TXBROADCASTPACKETS_GB    0x0744
#define DWC_MMC_TXMULTICASTPACKETS_GB    0x0740
#define DWC_MMC_TXUNICASTPACKETS_GB      0x073C
#define DWC_MMC_TX1024TOMAXOCTETS_GB     0x0738
#define DWC_MMC_TX512TO1023OCTETS_GB     0x0734
#define DWC_MMC_TX256TO511OCTETS_GB      0x0730
#define DWC_MMC_TX128TO255OCTETS_GB      0x072C
#define DWC_MMC_TX65TO127OCTETS_GB       0x0728
#define DWC_MMC_TX64OCTETS_GB            0x0724
#define DWC_MMC_TXMULTICASTPACKETS_G     0x0720
#define DWC_MMC_TXBROADCASTPACKETS_G     0x071C
#define DWC_MMC_TXPACKETCOUNT_GB         0x0718
#define DWC_MMC_TXOCTETCOUNT_GB          0x0714

#define DWC_MMC_RXLPITRANSCNTR           0x07F8
#define DWC_MMC_RXLPIUSCNTR              0x07F4
#define DWC_MMC_RXCTRLPACKETS_G          0x07E4
#define DWC_MMC_RXRCVERROR               0x07E0
#define DWC_MMC_RXWATCHDOG               0x07DC
#define DWC_MMC_RXVLANPACKETS_GB         0x07D8
#define DWC_MMC_RXFIFOOVERFLOW           0x07D4
#define DWC_MMC_RXPAUSEPACKETS           0x07D0
#define DWC_MMC_RXOUTOFRANGETYPE         0x07CC
#define DWC_MMC_RXLENGTHERROR            0x07C8
#define DWC_MMC_RXUNICASTPACKETS_G       0x07C4
#define DWC_MMC_RX1024TOMAXOCTETS_GB     0x07C0
#define DWC_MMC_RX512TO1023OCTETS_GB     0x07BC
#define DWC_MMC_RX256TO511OCTETS_GB      0x07B8
#define DWC_MMC_RX128TO255OCTETS_GB      0x07B4
#define DWC_MMC_RX65TO127OCTETS_GB       0x07B0
#define DWC_MMC_RX64OCTETS_GB            0x07AC
#define DWC_MMC_RXOVERSIZE_G             0x07A8
#define DWC_MMC_RXUNDERSIZE_G            0x07A4
#define DWC_MMC_RXJABBERERROR            0x07A0
#define DWC_MMC_RXRUNTERROR              0x079C
#define DWC_MMC_RXALIGNMENTERROR         0x0798
#define DWC_MMC_RXCRCERROR               0x0794
#define DWC_MMC_RXMULTICASTPACKETS_G     0x0790
#define DWC_MMC_RXBROADCASTPACKETS_G     0x078C
#define DWC_MMC_RXOCTETCOUNT_G           0x0788
#define DWC_MMC_RXOCTETCOUNT_GB          0x0784
#define DWC_MMC_RXPACKETCOUNT_GB         0x0780

static int debug = -1;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "DWC_eth_qos debug level (0=none,...,16=all)");

/* DMA ring descriptor. These are used as support descriptors for the HW DMA */
struct ring_desc {
        struct sk_buff *skb;
        dma_addr_t mapping;
        size_t len;
};

/* DMA hardware descriptor */
struct dwceqos_dma_desc {
        u32     des0;
        u32     des1;
        u32     des2;
        u32     des3;
} ____cacheline_aligned;

struct dwceqos_mmc_counters {
        __u64 txlpitranscntr;
        __u64 txpiuscntr;
        __u64 txoversize_g;
        __u64 txvlanpackets_g;
        __u64 txpausepackets;
        __u64 txexcessdef;
        __u64 txpacketcount_g;
        __u64 txoctetcount_g;
        __u64 txcarriererror;
        __u64 txexcesscol;
        __u64 txlatecol;
        __u64 txdeferred;
        __u64 txmulticol_g;
        __u64 txsinglecol_g;
        __u64 txunderflowerror;
        __u64 txbroadcastpackets_gb;
        __u64 txmulticastpackets_gb;
        __u64 txunicastpackets_gb;
        __u64 tx1024tomaxoctets_gb;
        __u64 tx512to1023octets_gb;
        __u64 tx256to511octets_gb;
        __u64 tx128to255octets_gb;
        __u64 tx65to127octets_gb;
        __u64 tx64octets_gb;
        __u64 txmulticastpackets_g;
        __u64 txbroadcastpackets_g;
        __u64 txpacketcount_gb;
        __u64 txoctetcount_gb;

        __u64 rxlpitranscntr;
        __u64 rxlpiuscntr;
        __u64 rxctrlpackets_g;
        __u64 rxrcverror;
        __u64 rxwatchdog;
        __u64 rxvlanpackets_gb;
        __u64 rxfifooverflow;
        __u64 rxpausepackets;
        __u64 rxoutofrangetype;
        __u64 rxlengtherror;
        __u64 rxunicastpackets_g;
        __u64 rx1024tomaxoctets_gb;
        __u64 rx512to1023octets_gb;
        __u64 rx256to511octets_gb;
        __u64 rx128to255octets_gb;
        __u64 rx65to127octets_gb;
        __u64 rx64octets_gb;
        __u64 rxoversize_g;
        __u64 rxundersize_g;
        __u64 rxjabbererror;
        __u64 rxrunterror;
        __u64 rxalignmenterror;
        __u64 rxcrcerror;
        __u64 rxmulticastpackets_g;
        __u64 rxbroadcastpackets_g;
        __u64 rxoctetcount_g;
        __u64 rxoctetcount_gb;
        __u64 rxpacketcount_gb;
};

/* Ethtool statistics */

struct dwceqos_stat {
        const char stat_name[ETH_GSTRING_LEN];
        int   offset;
};

#define STAT_ITEM(name, var) \
        {\
                name,\
                offsetof(struct dwceqos_mmc_counters, var),\
        }

static const struct dwceqos_stat dwceqos_ethtool_stats[] = {
        STAT_ITEM("tx_bytes", txoctetcount_gb),
        STAT_ITEM("tx_packets", txpacketcount_gb),
        STAT_ITEM("tx_unicst_packets", txunicastpackets_gb),
        STAT_ITEM("tx_broadcast_packets", txbroadcastpackets_gb),
        STAT_ITEM("tx_multicast_packets",  txmulticastpackets_gb),
        STAT_ITEM("tx_pause_packets", txpausepackets),
        STAT_ITEM("tx_up_to_64_byte_packets", tx64octets_gb),
        STAT_ITEM("tx_65_to_127_byte_packets",  tx65to127octets_gb),
        STAT_ITEM("tx_128_to_255_byte_packets", tx128to255octets_gb),
        STAT_ITEM("tx_256_to_511_byte_packets", tx256to511octets_gb),
        STAT_ITEM("tx_512_to_1023_byte_packets", tx512to1023octets_gb),
        STAT_ITEM("tx_1024_to_maxsize_packets", tx1024tomaxoctets_gb),
        STAT_ITEM("tx_underflow_errors", txunderflowerror),
        STAT_ITEM("tx_lpi_count", txlpitranscntr),

        STAT_ITEM("rx_bytes", rxoctetcount_gb),
        STAT_ITEM("rx_packets", rxpacketcount_gb),
        STAT_ITEM("rx_unicast_packets", rxunicastpackets_g),
        STAT_ITEM("rx_broadcast_packets", rxbroadcastpackets_g),
        STAT_ITEM("rx_multicast_packets", rxmulticastpackets_g),
        STAT_ITEM("rx_vlan_packets", rxvlanpackets_gb),
        STAT_ITEM("rx_pause_packets", rxpausepackets),
        STAT_ITEM("rx_up_to_64_byte_packets", rx64octets_gb),
        STAT_ITEM("rx_65_to_127_byte_packets",  rx65to127octets_gb),
        STAT_ITEM("rx_128_to_255_byte_packets", rx128to255octets_gb),
        STAT_ITEM("rx_256_to_511_byte_packets", rx256to511octets_gb),
        STAT_ITEM("rx_512_to_1023_byte_packets", rx512to1023octets_gb),
        STAT_ITEM("rx_1024_to_maxsize_packets", rx1024tomaxoctets_gb),
        STAT_ITEM("rx_fifo_overflow_errors", rxfifooverflow),
        STAT_ITEM("rx_oversize_packets", rxoversize_g),
        STAT_ITEM("rx_undersize_packets", rxundersize_g),
        STAT_ITEM("rx_jabbers", rxjabbererror),
        STAT_ITEM("rx_align_errors", rxalignmenterror),
        STAT_ITEM("rx_crc_errors", rxcrcerror),
        STAT_ITEM("rx_lpi_count", rxlpitranscntr),
};

/* Configuration of AXI bus parameters.
 * These values depend on the parameters set on the MAC core as well
 * as the AXI interconnect.
 */
struct dwceqos_bus_cfg {
        /* Enable AXI low-power interface. */
        bool en_lpi;
        /* Limit on number of outstanding AXI write requests. */
        u32 write_requests;
        /* Limit on number of outstanding AXI read requests. */
        u32 read_requests;
        /* Bitmap of allowed AXI burst lengths, 4-256 beats. */
        u32 burst_map;
        /* DMA Programmable burst length*/
        u32 tx_pbl;
        u32 rx_pbl;
};

struct dwceqos_flowcontrol {
        int autoneg;
        int rx;
        int rx_current;
        int tx;
        int tx_current;
};

struct net_local {
        void __iomem *baseaddr;
        struct clk *phy_ref_clk;
        struct clk *apb_pclk;

        struct device_node *phy_node;
        struct net_device *ndev;
        struct platform_device *pdev;

        u32 msg_enable;

        struct tasklet_struct tx_bdreclaim_tasklet;
        struct workqueue_struct *txtimeout_handler_wq;
        struct work_struct txtimeout_reinit;

        phy_interface_t phy_interface;
        struct phy_device *phy_dev;
        struct mii_bus *mii_bus;

        unsigned int link;
        unsigned int speed;
        unsigned int duplex;

        struct napi_struct napi;

        /* DMA Descriptor Areas */
        struct ring_desc *rx_skb;
        struct ring_desc *tx_skb;

        struct dwceqos_dma_desc *tx_descs;
        struct dwceqos_dma_desc *rx_descs;

        /* DMA Mapped Descriptor areas*/
        dma_addr_t tx_descs_addr;
        dma_addr_t rx_descs_addr;
        dma_addr_t tx_descs_tail_addr;
        dma_addr_t rx_descs_tail_addr;

        size_t tx_free;
        size_t tx_next;
        size_t rx_cur;
        size_t tx_cur;

        /* Spinlocks for accessing DMA Descriptors */
        spinlock_t tx_lock;

        /* Spinlock for register read-modify-writes. */
        spinlock_t hw_lock;

        u32 feature0;
        u32 feature1;
        u32 feature2;

        struct dwceqos_bus_cfg bus_cfg;
        bool en_tx_lpi_clockgating;

        int eee_enabled;
        int eee_active;
        int csr_val;
        u32 gso_size;

        struct dwceqos_mmc_counters mmc_counters;
        /* Protect the mmc_counter updates. */
        spinlock_t stats_lock;
        u32 mmc_rx_counters_mask;
        u32 mmc_tx_counters_mask;

        struct dwceqos_flowcontrol flowcontrol;

        /* Tracks the intermediate state of phy started but hardware
         * init not finished yet.
         */
        bool phy_defer;
};

static void dwceqos_read_mmc_counters(struct net_local *lp, u32 rx_mask,
                                      u32 tx_mask);

static void dwceqos_set_umac_addr(struct net_local *lp, unsigned char *addr,
                                  unsigned int reg_n);
static int dwceqos_stop(struct net_device *ndev);
static int dwceqos_open(struct net_device *ndev);
static void dwceqos_tx_poll_demand(struct net_local *lp);

static void dwceqos_set_rx_flowcontrol(struct net_local *lp, bool enable);
static void dwceqos_set_tx_flowcontrol(struct net_local *lp, bool enable);

static void dwceqos_reset_state(struct net_local *lp);

#define dwceqos_read(lp, reg)                                           \
        readl_relaxed(((void __iomem *)((lp)->baseaddr)) + (reg))
#define dwceqos_write(lp, reg, val)                                     \
        writel_relaxed((val), ((void __iomem *)((lp)->baseaddr)) + (reg))

static void dwceqos_reset_state(struct net_local *lp)
{
        lp->link    = 0;
        lp->speed   = 0;
        lp->duplex  = DUPLEX_UNKNOWN;
        lp->flowcontrol.rx_current = 0;
        lp->flowcontrol.tx_current = 0;
        lp->eee_active = 0;
        lp->eee_enabled = 0;
}

static void print_descriptor(struct net_local *lp, int index, int tx)
{
        struct dwceqos_dma_desc *dd;

        if (tx)
                dd = (struct dwceqos_dma_desc *)&lp->tx_descs[index];
        else
                dd = (struct dwceqos_dma_desc *)&lp->rx_descs[index];

        pr_info("%s DMA Descriptor #%d@%p Contents:\n", tx ? "TX" : "RX",
                index, dd);
        pr_info("0x%08x 0x%08x 0x%08x 0x%08x\n", dd->des0, dd->des1, dd->des2,
                dd->des3);
}

static void print_status(struct net_local *lp)
{
        size_t desci, i;

        pr_info("tx_free %zu, tx_cur %zu, tx_next %zu\n", lp->tx_free,
                lp->tx_cur, lp->tx_next);

        print_descriptor(lp, lp->rx_cur, 0);

        for (desci = (lp->tx_cur - 10) % DWCEQOS_TX_DCNT, i = 0;
                 i < DWCEQOS_TX_DCNT;
                 ++i) {
                print_descriptor(lp, desci, 1);
                desci = (desci + 1) % DWCEQOS_TX_DCNT;
        }

        pr_info("DMA_Debug_Status0:          0x%08x\n",
                dwceqos_read(lp, REG_DWCEQOS_DMA_DEBUG_ST0));
        pr_info("DMA_CH0_Status:             0x%08x\n",
                dwceqos_read(lp, REG_DWCEQOS_DMA_IS));
        pr_info("DMA_CH0_Current_App_TxDesc: 0x%08x\n",
                dwceqos_read(lp, 0x1144));
        pr_info("DMA_CH0_Current_App_TxBuff: 0x%08x\n",
                dwceqos_read(lp, 0x1154));
        pr_info("MTL_Debug_Status:      0x%08x\n",
                dwceqos_read(lp, REG_DWCEQOS_MTL_DEBUG_ST));
        pr_info("MTL_TXQ0_Debug_Status: 0x%08x\n",
                dwceqos_read(lp, REG_DWCEQOS_MTL_TXQ0_DEBUG_ST));
        pr_info("MTL_RXQ0_Debug_Status: 0x%08x\n",
                dwceqos_read(lp, REG_DWCEQOS_MTL_RXQ0_DEBUG_ST));
        pr_info("Current TX DMA: 0x%08x, RX DMA: 0x%08x\n",
                dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_CUR_TXDESC),
                dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_CUR_RXDESC));
}

static void dwceqos_mdio_set_csr(struct net_local *lp)
{
        int rate = clk_get_rate(lp->apb_pclk);

        if (rate <= 20000000)
                lp->csr_val = DWCEQOS_MAC_MDIO_ADDR_CR_20;
        else if (rate <= 35000000)
                lp->csr_val = DWCEQOS_MAC_MDIO_ADDR_CR_35;
        else if (rate <= 60000000)
                lp->csr_val = DWCEQOS_MAC_MDIO_ADDR_CR_60;
        else if (rate <= 100000000)
                lp->csr_val = DWCEQOS_MAC_MDIO_ADDR_CR_100;
        else if (rate <= 150000000)
                lp->csr_val = DWCEQOS_MAC_MDIO_ADDR_CR_150;
        else if (rate <= 250000000)
                lp->csr_val = DWCEQOS_MAC_MDIO_ADDR_CR_250;
}

/* Simple MDIO functions implementing mii_bus */
static int dwceqos_mdio_read(struct mii_bus *bus, int mii_id, int phyreg)
{
        struct net_local *lp = bus->priv;
        u32 regval;
        int i;
        int data;

        regval = DWCEQOS_MDIO_PHYADDR(mii_id) |
                DWCEQOS_MDIO_PHYREG(phyreg) |
                DWCEQOS_MAC_MDIO_ADDR_CR(lp->csr_val) |
                DWCEQOS_MAC_MDIO_ADDR_GB |
                DWCEQOS_MAC_MDIO_ADDR_GOC_READ;
        dwceqos_write(lp, REG_DWCEQOS_MAC_MDIO_ADDR, regval);

        for (i = 0; i < 5; ++i) {
                usleep_range(64, 128);
                if (!(dwceqos_read(lp, REG_DWCEQOS_MAC_MDIO_ADDR) &
                      DWCEQOS_MAC_MDIO_ADDR_GB))
                        break;
        }

        data = dwceqos_read(lp, REG_DWCEQOS_MAC_MDIO_DATA);
        if (i == 5) {
                netdev_warn(lp->ndev, "MDIO read timed out\n");
                data = 0xffff;
        }

        return data & 0xffff;
}

static int dwceqos_mdio_write(struct mii_bus *bus, int mii_id, int phyreg,
                              u16 value)
{
        struct net_local *lp = bus->priv;
        u32 regval;
        int i;

        dwceqos_write(lp, REG_DWCEQOS_MAC_MDIO_DATA, value);

        regval = DWCEQOS_MDIO_PHYADDR(mii_id) |
                DWCEQOS_MDIO_PHYREG(phyreg) |
                DWCEQOS_MAC_MDIO_ADDR_CR(lp->csr_val) |
                DWCEQOS_MAC_MDIO_ADDR_GB |
                DWCEQOS_MAC_MDIO_ADDR_GOC_WRITE;
        dwceqos_write(lp, REG_DWCEQOS_MAC_MDIO_ADDR, regval);

        for (i = 0; i < 5; ++i) {
                usleep_range(64, 128);
                if (!(dwceqos_read(lp, REG_DWCEQOS_MAC_MDIO_ADDR) &
                      DWCEQOS_MAC_MDIO_ADDR_GB))
                        break;
        }
        if (i == 5)
                netdev_warn(lp->ndev, "MDIO write timed out\n");
        return 0;
}

static int dwceqos_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd)
{
        struct net_local *lp = netdev_priv(ndev);
        struct phy_device *phydev = lp->phy_dev;

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

        if (!phydev)
                return -ENODEV;

        switch (cmd) {
        case SIOCGMIIPHY:
        case SIOCGMIIREG:
        case SIOCSMIIREG:
                return phy_mii_ioctl(phydev, rq, cmd);
        default:
                dev_info(&lp->pdev->dev, "ioctl %X not implemented.\n", cmd);
                return -EOPNOTSUPP;
        }
}

static void dwceqos_link_down(struct net_local *lp)
{
        u32 regval;
        unsigned long flags;

        /* Indicate link down to the LPI state machine */
        spin_lock_irqsave(&lp->hw_lock, flags);
        regval = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS);
        regval &= ~DWCEQOS_MAC_LPI_CTRL_STATUS_PLS;
        dwceqos_write(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS, regval);
        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_link_up(struct net_local *lp)
{
        u32 regval;
        unsigned long flags;

        /* Indicate link up to the LPI state machine */
        spin_lock_irqsave(&lp->hw_lock, flags);
        regval = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS);
        regval |= DWCEQOS_MAC_LPI_CTRL_STATUS_PLS;
        dwceqos_write(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS, regval);
        spin_unlock_irqrestore(&lp->hw_lock, flags);

        lp->eee_active = !phy_init_eee(lp->phy_dev, 0);

        /* Check for changed EEE capability */
        if (!lp->eee_active && lp->eee_enabled) {
                lp->eee_enabled = 0;

                spin_lock_irqsave(&lp->hw_lock, flags);
                regval = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS);
                regval &= ~DWCEQOS_LPI_CTRL_ENABLE_EEE;
                dwceqos_write(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS, regval);
                spin_unlock_irqrestore(&lp->hw_lock, flags);
        }
}

static void dwceqos_set_speed(struct net_local *lp)
{
        struct phy_device *phydev = lp->phy_dev;
        u32 regval;

        regval = dwceqos_read(lp, REG_DWCEQOS_MAC_CFG);
        regval &= ~(DWCEQOS_MAC_CFG_PS | DWCEQOS_MAC_CFG_FES |
                    DWCEQOS_MAC_CFG_DM);

        if (phydev->duplex)
                regval |= DWCEQOS_MAC_CFG_DM;
        if (phydev->speed == SPEED_10) {
                regval |= DWCEQOS_MAC_CFG_PS;
        } else if (phydev->speed == SPEED_100) {
                regval |= DWCEQOS_MAC_CFG_PS |
                        DWCEQOS_MAC_CFG_FES;
        } else if (phydev->speed != SPEED_1000) {
                netdev_err(lp->ndev,
                           "unknown PHY speed %d\n",
                           phydev->speed);
                return;
        }

        dwceqos_write(lp, REG_DWCEQOS_MAC_CFG, regval);
}

static void dwceqos_adjust_link(struct net_device *ndev)
{
        struct net_local *lp = netdev_priv(ndev);
        struct phy_device *phydev = lp->phy_dev;
        int status_change = 0;

        if (lp->phy_defer)
                return;

        if (phydev->link) {
                if ((lp->speed != phydev->speed) ||
                    (lp->duplex != phydev->duplex)) {
                        dwceqos_set_speed(lp);

                        lp->speed = phydev->speed;
                        lp->duplex = phydev->duplex;
                        status_change = 1;
                }

                if (lp->flowcontrol.autoneg) {
                        lp->flowcontrol.rx = phydev->pause ||
                                             phydev->asym_pause;
                        lp->flowcontrol.tx = phydev->pause ||
                                             phydev->asym_pause;
                }

                if (lp->flowcontrol.rx != lp->flowcontrol.rx_current) {
                        if (netif_msg_link(lp))
                                netdev_dbg(ndev, "set rx flow to %d\n",
                                           lp->flowcontrol.rx);
                        dwceqos_set_rx_flowcontrol(lp, lp->flowcontrol.rx);
                        lp->flowcontrol.rx_current = lp->flowcontrol.rx;
                }
                if (lp->flowcontrol.tx != lp->flowcontrol.tx_current) {
                        if (netif_msg_link(lp))
                                netdev_dbg(ndev, "set tx flow to %d\n",
                                           lp->flowcontrol.tx);
                        dwceqos_set_tx_flowcontrol(lp, lp->flowcontrol.tx);
                        lp->flowcontrol.tx_current = lp->flowcontrol.tx;
                }
        }

        if (phydev->link != lp->link) {
                lp->link = phydev->link;
                status_change = 1;
        }

        if (status_change) {
                if (phydev->link) {
                        lp->ndev->trans_start = jiffies;
                        dwceqos_link_up(lp);
                } else {
                        dwceqos_link_down(lp);
                }
                phy_print_status(phydev);
        }
}

static int dwceqos_mii_probe(struct net_device *ndev)
{
        struct net_local *lp = netdev_priv(ndev);
        struct phy_device *phydev = NULL;

        if (lp->phy_node) {
                phydev = of_phy_connect(lp->ndev,
                                        lp->phy_node,
                                        &dwceqos_adjust_link,
                                        0,
                                        lp->phy_interface);

                if (!phydev) {
                        netdev_err(ndev, "no PHY found\n");
                        return -1;
                }
        } else {
                netdev_err(ndev, "no PHY configured\n");
                return -ENODEV;
        }

        if (netif_msg_probe(lp))
                phy_attached_info(phydev);

        phydev->supported &= PHY_GBIT_FEATURES;

        lp->link    = 0;
        lp->speed   = 0;
        lp->duplex  = DUPLEX_UNKNOWN;
        lp->phy_dev = phydev;

        return 0;
}

static void dwceqos_alloc_rxring_desc(struct net_local *lp, int index)
{
        struct sk_buff *new_skb;
        dma_addr_t new_skb_baddr = 0;

        new_skb = netdev_alloc_skb(lp->ndev, DWCEQOS_RX_BUF_SIZE);

        if (!new_skb) {
                netdev_err(lp->ndev, "alloc_skb error for desc %d\n", index);
                goto err_out;
        }

        new_skb_baddr = dma_map_single(lp->ndev->dev.parent,
                                       new_skb->data, DWCEQOS_RX_BUF_SIZE,
                                       DMA_FROM_DEVICE);
        if (dma_mapping_error(lp->ndev->dev.parent, new_skb_baddr)) {
                netdev_err(lp->ndev, "DMA map error\n");
                dev_kfree_skb(new_skb);
                new_skb = NULL;
                goto err_out;
        }

        lp->rx_descs[index].des0 = new_skb_baddr;
        lp->rx_descs[index].des1 = 0;
        lp->rx_descs[index].des2 = 0;
        lp->rx_descs[index].des3 = DWCEQOS_DMA_RDES3_INTE |
                                   DWCEQOS_DMA_RDES3_BUF1V |
                                   DWCEQOS_DMA_RDES3_OWN;

        lp->rx_skb[index].mapping = new_skb_baddr;
        lp->rx_skb[index].len = DWCEQOS_RX_BUF_SIZE;

err_out:
        lp->rx_skb[index].skb = new_skb;
}

static void dwceqos_clean_rings(struct net_local *lp)
{
        int i;

        if (lp->rx_skb) {
                for (i = 0; i < DWCEQOS_RX_DCNT; i++) {
                        if (lp->rx_skb[i].skb) {
                                dma_unmap_single(lp->ndev->dev.parent,
                                                 lp->rx_skb[i].mapping,
                                                 lp->rx_skb[i].len,
                                                 DMA_FROM_DEVICE);

                                dev_kfree_skb(lp->rx_skb[i].skb);
                                lp->rx_skb[i].skb = NULL;
                                lp->rx_skb[i].mapping = 0;
                        }
                }
        }

        if (lp->tx_skb) {
                for (i = 0; i < DWCEQOS_TX_DCNT; i++) {
                        if (lp->tx_skb[i].skb) {
                                dev_kfree_skb(lp->tx_skb[i].skb);
                                lp->tx_skb[i].skb = NULL;
                        }
                        if (lp->tx_skb[i].mapping) {
                                dma_unmap_single(lp->ndev->dev.parent,
                                                 lp->tx_skb[i].mapping,
                                                 lp->tx_skb[i].len,
                                                 DMA_TO_DEVICE);
                                lp->tx_skb[i].mapping = 0;
                        }
                }
        }
}

static void dwceqos_descriptor_free(struct net_local *lp)
{
        int size;

        dwceqos_clean_rings(lp);

        kfree(lp->tx_skb);
        lp->tx_skb = NULL;
        kfree(lp->rx_skb);
        lp->rx_skb = NULL;

        size = DWCEQOS_RX_DCNT * sizeof(struct dwceqos_dma_desc);
        if (lp->rx_descs) {
                dma_free_coherent(lp->ndev->dev.parent, size,
                                  (void *)(lp->rx_descs), lp->rx_descs_addr);
                lp->rx_descs = NULL;
        }

        size = DWCEQOS_TX_DCNT * sizeof(struct dwceqos_dma_desc);
        if (lp->tx_descs) {
                dma_free_coherent(lp->ndev->dev.parent, size,
                                  (void *)(lp->tx_descs), lp->tx_descs_addr);
                lp->tx_descs = NULL;
        }
}

static int dwceqos_descriptor_init(struct net_local *lp)
{
        int size;
        u32 i;

        lp->gso_size = 0;

        lp->tx_skb = NULL;
        lp->rx_skb = NULL;
        lp->rx_descs = NULL;
        lp->tx_descs = NULL;

        /* Reset the DMA indexes */
        lp->rx_cur = 0;
        lp->tx_cur = 0;
        lp->tx_next = 0;
        lp->tx_free = DWCEQOS_TX_DCNT;

        /* Allocate Ring descriptors */
        size = DWCEQOS_RX_DCNT * sizeof(struct ring_desc);
        lp->rx_skb = kzalloc(size, GFP_KERNEL);
        if (!lp->rx_skb)
                goto err_out;

        size = DWCEQOS_TX_DCNT * sizeof(struct ring_desc);
        lp->tx_skb = kzalloc(size, GFP_KERNEL);
        if (!lp->tx_skb)
                goto err_out;

        /* Allocate DMA descriptors */
        size = DWCEQOS_RX_DCNT * sizeof(struct dwceqos_dma_desc);
        lp->rx_descs = dma_alloc_coherent(lp->ndev->dev.parent, size,
                        &lp->rx_descs_addr, GFP_KERNEL);
        if (!lp->rx_descs)
                goto err_out;
        lp->rx_descs_tail_addr = lp->rx_descs_addr +
                sizeof(struct dwceqos_dma_desc) * DWCEQOS_RX_DCNT;

        size = DWCEQOS_TX_DCNT * sizeof(struct dwceqos_dma_desc);
        lp->tx_descs = dma_alloc_coherent(lp->ndev->dev.parent, size,
                        &lp->tx_descs_addr, GFP_KERNEL);
        if (!lp->tx_descs)
                goto err_out;
        lp->tx_descs_tail_addr = lp->tx_descs_addr +
                sizeof(struct dwceqos_dma_desc) * DWCEQOS_TX_DCNT;

        /* Initialize RX Ring Descriptors and buffers */
        for (i = 0; i < DWCEQOS_RX_DCNT; ++i) {
                dwceqos_alloc_rxring_desc(lp, i);
                if (!(lp->rx_skb[lp->rx_cur].skb))
                        goto err_out;
        }

        /* Initialize TX Descriptors */
        for (i = 0; i < DWCEQOS_TX_DCNT; ++i) {
                lp->tx_descs[i].des0 = 0;
                lp->tx_descs[i].des1 = 0;
                lp->tx_descs[i].des2 = 0;
                lp->tx_descs[i].des3 = 0;
        }

        /* Make descriptor writes visible to the DMA. */
        wmb();

        return 0;

err_out:
        dwceqos_descriptor_free(lp);
        return -ENOMEM;
}

static int dwceqos_packet_avail(struct net_local *lp)
{
        return !(lp->rx_descs[lp->rx_cur].des3 & DWCEQOS_DMA_RDES3_OWN);
}

static void dwceqos_get_hwfeatures(struct net_local *lp)
{
        lp->feature0 = dwceqos_read(lp, REG_DWCEQOS_MAC_HW_FEATURE0);
        lp->feature1 = dwceqos_read(lp, REG_DWCEQOS_MAC_HW_FEATURE1);
        lp->feature2 = dwceqos_read(lp, REG_DWCEQOS_MAC_HW_FEATURE2);
}

static void dwceqos_dma_enable_txirq(struct net_local *lp)
{
        u32 regval;
        unsigned long flags;

        spin_lock_irqsave(&lp->hw_lock, flags);
        regval = dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_IE);
        regval |= DWCEQOS_DMA_CH0_IE_TIE;
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE, regval);
        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_dma_disable_txirq(struct net_local *lp)
{
        u32 regval;
        unsigned long flags;

        spin_lock_irqsave(&lp->hw_lock, flags);
        regval = dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_IE);
        regval &= ~DWCEQOS_DMA_CH0_IE_TIE;
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE, regval);
        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_dma_enable_rxirq(struct net_local *lp)
{
        u32 regval;
        unsigned long flags;

        spin_lock_irqsave(&lp->hw_lock, flags);
        regval = dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_IE);
        regval |= DWCEQOS_DMA_CH0_IE_RIE;
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE, regval);
        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_dma_disable_rxirq(struct net_local *lp)
{
        u32 regval;
        unsigned long flags;

        spin_lock_irqsave(&lp->hw_lock, flags);
        regval = dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_IE);
        regval &= ~DWCEQOS_DMA_CH0_IE_RIE;
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE, regval);
        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_enable_mmc_interrupt(struct net_local *lp)
{
        dwceqos_write(lp, REG_DWCEQOS_MMC_RXIRQMASK, 0);
        dwceqos_write(lp, REG_DWCEQOS_MMC_TXIRQMASK, 0);
}

static int dwceqos_mii_init(struct net_local *lp)
{
        int ret = -ENXIO;
        struct resource res;
        struct device_node *mdionode;

        mdionode = of_get_child_by_name(lp->pdev->dev.of_node, "mdio");

        if (!mdionode)
                return 0;

        lp->mii_bus = mdiobus_alloc();
        if (!lp->mii_bus) {
                ret = -ENOMEM;
                goto err_out;
        }

        lp->mii_bus->name  = "DWCEQOS MII bus";
        lp->mii_bus->read  = &dwceqos_mdio_read;
        lp->mii_bus->write = &dwceqos_mdio_write;
        lp->mii_bus->priv = lp;
        lp->mii_bus->parent = &lp->ndev->dev;

        of_address_to_resource(lp->pdev->dev.of_node, 0, &res);
        snprintf(lp->mii_bus->id, MII_BUS_ID_SIZE, "%.8llx",
                 (unsigned long long)res.start);
        if (of_mdiobus_register(lp->mii_bus, mdionode))
                goto err_out_free_mdiobus;

        return 0;

err_out_free_mdiobus:
        mdiobus_free(lp->mii_bus);
err_out:
        of_node_put(mdionode);
        return ret;
}

/* DMA reset. When issued also resets all MTL and MAC registers as well */
static void dwceqos_reset_hw(struct net_local *lp)
{
        /* Wait (at most) 0.5 seconds for DMA reset*/
        int i = 5000;
        u32 reg;

        /* Force gigabit to guarantee a TX clock for GMII. */
        reg = dwceqos_read(lp, REG_DWCEQOS_MAC_CFG);
        reg &= ~(DWCEQOS_MAC_CFG_PS | DWCEQOS_MAC_CFG_FES);
        reg |= DWCEQOS_MAC_CFG_DM;
        dwceqos_write(lp, REG_DWCEQOS_MAC_CFG, reg);

        dwceqos_write(lp, REG_DWCEQOS_DMA_MODE, DWCEQOS_DMA_MODE_SWR);

        do {
                udelay(100);
                i--;
                reg = dwceqos_read(lp, REG_DWCEQOS_DMA_MODE);
        } while ((reg & DWCEQOS_DMA_MODE_SWR) && i);
        /* We might experience a timeout if the chip clock mux is broken */
        if (!i)
                netdev_err(lp->ndev, "DMA reset timed out!\n");
}

static void dwceqos_fatal_bus_error(struct net_local *lp, u32 dma_status)
{
        if (dma_status & DWCEQOS_DMA_CH0_IS_TEB) {
                netdev_err(lp->ndev, "txdma bus error %s %s (status=%08x)\n",
                           dma_status & DWCEQOS_DMA_CH0_IS_TX_ERR_READ ?
                                "read" : "write",
                           dma_status & DWCEQOS_DMA_CH0_IS_TX_ERR_DESCR ?
                                "descr" : "data",
                           dma_status);

                print_status(lp);
        }
        if (dma_status & DWCEQOS_DMA_CH0_IS_REB) {
                netdev_err(lp->ndev, "rxdma bus error %s %s (status=%08x)\n",
                           dma_status & DWCEQOS_DMA_CH0_IS_RX_ERR_READ ?
                                "read" : "write",
                           dma_status & DWCEQOS_DMA_CH0_IS_RX_ERR_DESCR ?
                                "descr" : "data",
                           dma_status);

                print_status(lp);
        }
}

static void dwceqos_mmc_interrupt(struct net_local *lp)
{
        unsigned long flags;

        spin_lock_irqsave(&lp->stats_lock, flags);

        /* A latched mmc interrupt can not be masked, we must read
         *  all the counters with an interrupt pending.
         */
        dwceqos_read_mmc_counters(lp,
                                  dwceqos_read(lp, REG_DWCEQOS_MMC_RXIRQ),
                                  dwceqos_read(lp, REG_DWCEQOS_MMC_TXIRQ));

        spin_unlock_irqrestore(&lp->stats_lock, flags);
}

static void dwceqos_mac_interrupt(struct net_local *lp)
{
        u32 cause;

        cause = dwceqos_read(lp, REG_DWCEQOS_MAC_IS);

        if (cause & DWCEQOS_MAC_IS_MMC_INT)
                dwceqos_mmc_interrupt(lp);
}

static irqreturn_t dwceqos_interrupt(int irq, void *dev_id)
{
        struct net_device *ndev = dev_id;
        struct net_local *lp = netdev_priv(ndev);

        u32 cause;
        u32 dma_status;
        irqreturn_t ret = IRQ_NONE;

        cause = dwceqos_read(lp, REG_DWCEQOS_DMA_IS);
        /* DMA Channel 0 Interrupt */
        if (cause & DWCEQOS_DMA_IS_DC0IS) {
                dma_status = dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_STA);

                /* Transmit Interrupt */
                if (dma_status & DWCEQOS_DMA_CH0_IS_TI) {
                        tasklet_schedule(&lp->tx_bdreclaim_tasklet);
                        dwceqos_dma_disable_txirq(lp);
                }

                /* Receive Interrupt */
                if (dma_status & DWCEQOS_DMA_CH0_IS_RI) {
                        /* Disable RX IRQs */
                        dwceqos_dma_disable_rxirq(lp);
                        napi_schedule(&lp->napi);
                }

                /* Fatal Bus Error interrupt */
                if (unlikely(dma_status & DWCEQOS_DMA_CH0_IS_FBE)) {
                        dwceqos_fatal_bus_error(lp, dma_status);

                        /* errata 9000831707 */
                        dma_status |= DWCEQOS_DMA_CH0_IS_TEB |
                                      DWCEQOS_DMA_CH0_IS_REB;
                }

                /* Ack all DMA Channel 0 IRQs */
                dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_STA, dma_status);
                ret = IRQ_HANDLED;
        }

        if (cause & DWCEQOS_DMA_IS_MTLIS) {
                u32 val = dwceqos_read(lp, REG_DWCEQOS_MTL_Q0_ISCTRL);

                dwceqos_write(lp, REG_DWCEQOS_MTL_Q0_ISCTRL, val);
                ret = IRQ_HANDLED;
        }

        if (cause & DWCEQOS_DMA_IS_MACIS) {
                dwceqos_mac_interrupt(lp);
                ret = IRQ_HANDLED;
        }
        return ret;
}

static void dwceqos_set_rx_flowcontrol(struct net_local *lp, bool enable)
{
        u32 regval;
        unsigned long flags;

        spin_lock_irqsave(&lp->hw_lock, flags);

        regval = dwceqos_read(lp, REG_DWCEQOS_MAC_RX_FLOW_CTRL);
        if (enable)
                regval |= DWCEQOS_MAC_RX_FLOW_CTRL_RFE;
        else
                regval &= ~DWCEQOS_MAC_RX_FLOW_CTRL_RFE;
        dwceqos_write(lp, REG_DWCEQOS_MAC_RX_FLOW_CTRL, regval);

        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_set_tx_flowcontrol(struct net_local *lp, bool enable)
{
        u32 regval;
        unsigned long flags;

        spin_lock_irqsave(&lp->hw_lock, flags);

        /* MTL flow control */
        regval = dwceqos_read(lp, REG_DWCEQOS_MTL_RXQ0_OPER);
        if (enable)
                regval |= DWCEQOS_MTL_RXQ_EHFC;
        else
                regval &= ~DWCEQOS_MTL_RXQ_EHFC;

        dwceqos_write(lp, REG_DWCEQOS_MTL_RXQ0_OPER, regval);

        /* MAC flow control */
        regval = dwceqos_read(lp, REG_DWCEQOS_MAC_Q0_TX_FLOW);
        if (enable)
                regval |= DWCEQOS_MAC_Q0_TX_FLOW_TFE;
        else
                regval &= ~DWCEQOS_MAC_Q0_TX_FLOW_TFE;
        dwceqos_write(lp, REG_DWCEQOS_MAC_Q0_TX_FLOW, regval);

        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_configure_flow_control(struct net_local *lp)
{
        u32 regval;
        unsigned long flags;
        int RQS, RFD, RFA;

        spin_lock_irqsave(&lp->hw_lock, flags);

        regval = dwceqos_read(lp, REG_DWCEQOS_MTL_RXQ0_OPER);

        /* The queue size is in units of 256 bytes. We want 512 bytes units for
         * the threshold fields.
         */
        RQS = ((regval >> 20) & 0x3FF) + 1;
        RQS /= 2;

        /* The thresholds are relative to a full queue, with a bias
         * of 1 KiByte below full.
         */
        RFD = RQS / 2 - 2;
        RFA = RQS / 8 - 2;

        regval = (regval & 0xFFF000FF) | (RFD << 14) | (RFA << 8);

        if (RFD >= 0 && RFA >= 0) {
                dwceqos_write(lp, REG_DWCEQOS_MTL_RXQ0_OPER, regval);
        } else {
                netdev_warn(lp->ndev,
                            "FIFO too small for flow control.");
        }

        regval = DWCEQOS_MAC_Q0_TX_FLOW_PT(256) |
                 DWCEQOS_MAC_Q0_TX_FLOW_PLT_4_SLOTS;

        dwceqos_write(lp, REG_DWCEQOS_MAC_Q0_TX_FLOW, regval);

        spin_unlock_irqrestore(&lp->hw_lock, flags);
}

static void dwceqos_configure_clock(struct net_local *lp)
{
        unsigned long rate_mhz = clk_get_rate(lp->apb_pclk) / 1000000;

        BUG_ON(!rate_mhz);

        dwceqos_write(lp,
                      REG_DWCEQOS_MAC_1US_TIC_COUNTER,
                      DWCEQOS_MAC_1US_TIC_COUNTER_VAL(rate_mhz - 1));
}

static void dwceqos_configure_bus(struct net_local *lp)
{
        u32 sysbus_reg;

        /* N.B. We do not support the Fixed Burst mode because it
         * opens a race window by making HW access to DMA descriptors
         * non-atomic.
         */

        sysbus_reg = DWCEQOS_DMA_SYSBUS_MODE_AAL;

        if (lp->bus_cfg.en_lpi)
                sysbus_reg |= DWCEQOS_DMA_SYSBUS_MODE_EN_LPI;

        if (lp->bus_cfg.burst_map)
                sysbus_reg |= DWCEQOS_DMA_SYSBUS_MODE_BURST(
                        lp->bus_cfg.burst_map);
        else
                sysbus_reg |= DWCEQOS_DMA_SYSBUS_MODE_BURST(
                        DWCEQOS_DMA_SYSBUS_MODE_BURST_DEFAULT);

        if (lp->bus_cfg.read_requests)
                sysbus_reg |= DWCEQOS_DMA_SYSBUS_MODE_RD_OSR_LIMIT(
                        lp->bus_cfg.read_requests - 1);
        else
                sysbus_reg |= DWCEQOS_DMA_SYSBUS_MODE_RD_OSR_LIMIT(
                        DWCEQOS_DMA_SYSBUS_MODE_RD_OSR_LIMIT_DEFAULT);

        if (lp->bus_cfg.write_requests)
                sysbus_reg |= DWCEQOS_DMA_SYSBUS_MODE_WR_OSR_LIMIT(
                        lp->bus_cfg.write_requests - 1);
        else
                sysbus_reg |= DWCEQOS_DMA_SYSBUS_MODE_WR_OSR_LIMIT(
                        DWCEQOS_DMA_SYSBUS_MODE_WR_OSR_LIMIT_DEFAULT);

        if (netif_msg_hw(lp))
                netdev_dbg(lp->ndev, "SysbusMode %#X\n", sysbus_reg);

        dwceqos_write(lp, REG_DWCEQOS_DMA_SYSBUS_MODE, sysbus_reg);
}

static void dwceqos_init_hw(struct net_local *lp)
{
        u32 regval;
        u32 buswidth;
        u32 dma_skip;

        /* Software reset */
        dwceqos_reset_hw(lp);

        dwceqos_configure_bus(lp);

        /* Probe data bus width, 32/64/128 bits. */
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_TXDESC_TAIL, 0xF);
        regval = dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_TXDESC_TAIL);
        buswidth = (regval ^ 0xF) + 1;

        /* Cache-align dma descriptors. */
        dma_skip = (sizeof(struct dwceqos_dma_desc) - 16) / buswidth;
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_CTRL,
                      DWCEQOS_DMA_CH_CTRL_DSL(dma_skip) |
                      DWCEQOS_DMA_CH_CTRL_PBLX8);

        /* Initialize DMA Channel 0 */
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_TXDESC_LEN, DWCEQOS_TX_DCNT - 1);
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_RXDESC_LEN, DWCEQOS_RX_DCNT - 1);
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_TXDESC_LIST,
                      (u32)lp->tx_descs_addr);
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_RXDESC_LIST,
                      (u32)lp->rx_descs_addr);

        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_TXDESC_TAIL,
                      lp->tx_descs_tail_addr);
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_RXDESC_TAIL,
                      lp->rx_descs_tail_addr);

        if (lp->bus_cfg.tx_pbl)
                regval = DWCEQOS_DMA_CH_CTRL_PBL(lp->bus_cfg.tx_pbl);
        else
                regval = DWCEQOS_DMA_CH_CTRL_PBL(2);

        /* Enable TSO if the HW support it */
        if (lp->feature1 & DWCEQOS_MAC_HW_FEATURE1_TSOEN)
                regval |= DWCEQOS_DMA_CH_TX_TSE;

        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_TX_CTRL, regval);

        if (lp->bus_cfg.rx_pbl)
                regval = DWCEQOS_DMA_CH_CTRL_PBL(lp->bus_cfg.rx_pbl);
        else
                regval = DWCEQOS_DMA_CH_CTRL_PBL(2);

        regval |= DWCEQOS_DMA_CH_RX_CTRL_BUFSIZE(DWCEQOS_DWCEQOS_RX_BUF_SIZE);
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_RX_CTRL, regval);

        regval |= DWCEQOS_DMA_CH_CTRL_START;
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_RX_CTRL, regval);

        /* Initialize MTL Queues */
        regval = DWCEQOS_MTL_SCHALG_STRICT;
        dwceqos_write(lp, REG_DWCEQOS_MTL_OPER, regval);

        regval = DWCEQOS_MTL_TXQ_SIZE(
                        DWCEQOS_MAC_HW_FEATURE1_TXFIFOSIZE(lp->feature1)) |
                DWCEQOS_MTL_TXQ_TXQEN | DWCEQOS_MTL_TXQ_TSF |
                DWCEQOS_MTL_TXQ_TTC512;
        dwceqos_write(lp, REG_DWCEQOS_MTL_TXQ0_OPER, regval);

        regval = DWCEQOS_MTL_RXQ_SIZE(
                        DWCEQOS_MAC_HW_FEATURE1_RXFIFOSIZE(lp->feature1)) |
                DWCEQOS_MTL_RXQ_FUP | DWCEQOS_MTL_RXQ_FEP | DWCEQOS_MTL_RXQ_RSF;
        dwceqos_write(lp, REG_DWCEQOS_MTL_RXQ0_OPER, regval);

        dwceqos_configure_flow_control(lp);

        /* Initialize MAC */
        dwceqos_set_umac_addr(lp, lp->ndev->dev_addr, 0);

        lp->eee_enabled = 0;

        dwceqos_configure_clock(lp);

        /* MMC counters */

        /* probe implemented counters */
        dwceqos_write(lp, REG_DWCEQOS_MMC_RXIRQMASK, ~0u);
        dwceqos_write(lp, REG_DWCEQOS_MMC_TXIRQMASK, ~0u);
        lp->mmc_rx_counters_mask = dwceqos_read(lp, REG_DWCEQOS_MMC_RXIRQMASK);
        lp->mmc_tx_counters_mask = dwceqos_read(lp, REG_DWCEQOS_MMC_TXIRQMASK);

        dwceqos_write(lp, REG_DWCEQOS_MMC_CTRL, DWCEQOS_MMC_CTRL_CNTRST |
                DWCEQOS_MMC_CTRL_RSTONRD);
        dwceqos_enable_mmc_interrupt(lp);

        /* Enable Interrupts */
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE,
                      DWCEQOS_DMA_CH0_IE_NIE |
                      DWCEQOS_DMA_CH0_IE_RIE | DWCEQOS_DMA_CH0_IE_TIE |
                      DWCEQOS_DMA_CH0_IE_AIE |
                      DWCEQOS_DMA_CH0_IE_FBEE);

        dwceqos_write(lp, REG_DWCEQOS_MAC_IE, 0);

        dwceqos_write(lp, REG_DWCEQOS_MAC_CFG, DWCEQOS_MAC_CFG_IPC |
                DWCEQOS_MAC_CFG_DM | DWCEQOS_MAC_CFG_TE | DWCEQOS_MAC_CFG_RE);

        /* Start TX DMA */
        regval = dwceqos_read(lp, REG_DWCEQOS_DMA_CH0_TX_CTRL);
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_TX_CTRL,
                      regval | DWCEQOS_DMA_CH_CTRL_START);

        /* Enable MAC TX/RX */
        regval = dwceqos_read(lp, REG_DWCEQOS_MAC_CFG);
        dwceqos_write(lp, REG_DWCEQOS_MAC_CFG,
                      regval | DWCEQOS_MAC_CFG_TE | DWCEQOS_MAC_CFG_RE);

        lp->phy_defer = false;
        mutex_lock(&lp->phy_dev->lock);
        phy_read_status(lp->phy_dev);
        dwceqos_adjust_link(lp->ndev);
        mutex_unlock(&lp->phy_dev->lock);
}

static void dwceqos_tx_reclaim(unsigned long data)
{
        struct net_device *ndev = (struct net_device *)data;
        struct net_local *lp = netdev_priv(ndev);
        unsigned int tx_bytes = 0;
        unsigned int tx_packets = 0;

        spin_lock(&lp->tx_lock);

        while (lp->tx_free < DWCEQOS_TX_DCNT) {
                struct dwceqos_dma_desc *dd = &lp->tx_descs[lp->tx_cur];
                struct ring_desc *rd = &lp->tx_skb[lp->tx_cur];

                /* Descriptor still being held by DMA ? */
                if (dd->des3 & DWCEQOS_DMA_TDES3_OWN)
                        break;

                if (rd->mapping)
                        dma_unmap_single(ndev->dev.parent, rd->mapping, rd->len,
                                         DMA_TO_DEVICE);

                if (unlikely(rd->skb)) {
                        ++tx_packets;
                        tx_bytes += rd->skb->len;
                        dev_consume_skb_any(rd->skb);
                }

                rd->skb = NULL;
                rd->mapping = 0;
                lp->tx_free++;
                lp->tx_cur = (lp->tx_cur + 1) % DWCEQOS_TX_DCNT;

                if ((dd->des3 & DWCEQOS_DMA_TDES3_LD) &&
                    (dd->des3 & DWCEQOS_DMA_RDES3_ES)) {
                        if (netif_msg_tx_err(lp))
                                netdev_err(ndev, "TX Error, TDES3 = 0x%x\n",
                                           dd->des3);
                        if (netif_msg_hw(lp))
                                print_status(lp);
                }
        }
        spin_unlock(&lp->tx_lock);

        netdev_completed_queue(ndev, tx_packets, tx_bytes);

        dwceqos_dma_enable_txirq(lp);
        netif_wake_queue(ndev);
}

static int dwceqos_rx(struct net_local *lp, int budget)
{
        struct sk_buff *skb;
        u32 tot_size = 0;
        unsigned int n_packets = 0;
        unsigned int n_descs = 0;
        u32 len;

        struct dwceqos_dma_desc *dd;
        struct sk_buff *new_skb;
        dma_addr_t new_skb_baddr = 0;

        while (n_descs < budget) {
                if (!dwceqos_packet_avail(lp))
                        break;

                new_skb = netdev_alloc_skb(lp->ndev, DWCEQOS_RX_BUF_SIZE);
                if (!new_skb) {
                        netdev_err(lp->ndev, "no memory for new sk_buff\n");
                        break;
                }

                /* Get dma handle of skb->data */
                new_skb_baddr = (u32)dma_map_single(lp->ndev->dev.parent,
                                        new_skb->data,
                                        DWCEQOS_RX_BUF_SIZE,
                                        DMA_FROM_DEVICE);
                if (dma_mapping_error(lp->ndev->dev.parent, new_skb_baddr)) {
                        netdev_err(lp->ndev, "DMA map error\n");
                        dev_kfree_skb(new_skb);
                        break;
                }

                /* Read descriptor data after reading owner bit. */
                dma_rmb();

                dd = &lp->rx_descs[lp->rx_cur];
                len = DWCEQOS_DMA_RDES3_PL(dd->des3);
                skb = lp->rx_skb[lp->rx_cur].skb;

                /* Unmap old buffer */
                dma_unmap_single(lp->ndev->dev.parent,
                                 lp->rx_skb[lp->rx_cur].mapping,
                                 lp->rx_skb[lp->rx_cur].len, DMA_FROM_DEVICE);

                /* Discard packet on reception error or bad checksum */
                if ((dd->des3 & DWCEQOS_DMA_RDES3_ES) ||
                    (dd->des1 & DWCEQOS_DMA_RDES1_IPCE)) {
                        dev_kfree_skb(skb);
                        skb = NULL;
                } else {
                        skb_put(skb, len);
                        skb->protocol = eth_type_trans(skb, lp->ndev);
                        switch (dd->des1 & DWCEQOS_DMA_RDES1_PT) {
                        case DWCEQOS_DMA_RDES1_PT_UDP:
                        case DWCEQOS_DMA_RDES1_PT_TCP:
                        case DWCEQOS_DMA_RDES1_PT_ICMP:
                                skb->ip_summed = CHECKSUM_UNNECESSARY;
                                break;
                        default:
                                skb->ip_summed = CHECKSUM_NONE;
                                break;
                        }
                }

                if (unlikely(!skb)) {
                        if (netif_msg_rx_err(lp))
                                netdev_dbg(lp->ndev, "rx error: des3=%X\n",
                                           lp->rx_descs[lp->rx_cur].des3);
                } else {
                        tot_size += skb->len;
                        n_packets++;

                        netif_receive_skb(skb);
                }

                lp->rx_descs[lp->rx_cur].des0 = new_skb_baddr;
                lp->rx_descs[lp->rx_cur].des1 = 0;
                lp->rx_descs[lp->rx_cur].des2 = 0;
                /* The DMA must observe des0/1/2 written before des3. */
                wmb();
                lp->rx_descs[lp->rx_cur].des3 = DWCEQOS_DMA_RDES3_INTE |
                                                DWCEQOS_DMA_RDES3_OWN  |
                                                DWCEQOS_DMA_RDES3_BUF1V;

                lp->rx_skb[lp->rx_cur].mapping = new_skb_baddr;
                lp->rx_skb[lp->rx_cur].len = DWCEQOS_RX_BUF_SIZE;
                lp->rx_skb[lp->rx_cur].skb = new_skb;

                n_descs++;
                lp->rx_cur = (lp->rx_cur + 1) % DWCEQOS_RX_DCNT;
        }

        /* Make sure any ownership update is written to the descriptors before
         * DMA wakeup.
         */
        wmb();

        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_STA, DWCEQOS_DMA_CH0_IS_RI);
        /* Wake up RX by writing tail pointer */
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_RXDESC_TAIL,
                      lp->rx_descs_tail_addr);

        return n_descs;
}

static int dwceqos_rx_poll(struct napi_struct *napi, int budget)
{
        struct net_local *lp = container_of(napi, struct net_local, napi);
        int work_done = 0;

        work_done = dwceqos_rx(lp, budget - work_done);

        if (!dwceqos_packet_avail(lp) && work_done < budget) {
                napi_complete(napi);
                dwceqos_dma_enable_rxirq(lp);
        } else {
                work_done = budget;
        }

        return work_done;
}

/* Reinitialize function if a TX timed out */
static void dwceqos_reinit_for_txtimeout(struct work_struct *data)
{
        struct net_local *lp = container_of(data, struct net_local,
                txtimeout_reinit);

        netdev_err(lp->ndev, "transmit timeout %d s, resetting...\n",
                   DWCEQOS_TX_TIMEOUT);

        if (netif_msg_hw(lp))
                print_status(lp);

        rtnl_lock();
        dwceqos_stop(lp->ndev);
        dwceqos_open(lp->ndev);
        rtnl_unlock();
}

/* DT Probing function called by main probe */
static inline int dwceqos_probe_config_dt(struct platform_device *pdev)
{
        struct net_device *ndev;
        struct net_local *lp;
        const void *mac_address;
        struct dwceqos_bus_cfg *bus_cfg;
        struct device_node *np = pdev->dev.of_node;

        ndev = platform_get_drvdata(pdev);
        lp = netdev_priv(ndev);
        bus_cfg = &lp->bus_cfg;

        /* Set the MAC address. */
        mac_address = of_get_mac_address(pdev->dev.of_node);
        if (mac_address)
                ether_addr_copy(ndev->dev_addr, mac_address);

        /* These are all optional parameters */
        lp->en_tx_lpi_clockgating =  of_property_read_bool(np,
                "snps,en-tx-lpi-clockgating");
        bus_cfg->en_lpi = of_property_read_bool(np, "snps,en-lpi");
        of_property_read_u32(np, "snps,write-requests",
                             &bus_cfg->write_requests);
        of_property_read_u32(np, "snps,read-requests", &bus_cfg->read_requests);
        of_property_read_u32(np, "snps,burst-map", &bus_cfg->burst_map);
        of_property_read_u32(np, "snps,txpbl", &bus_cfg->tx_pbl);
        of_property_read_u32(np, "snps,rxpbl", &bus_cfg->rx_pbl);

        netdev_dbg(ndev, "BusCfg: lpi:%u wr:%u rr:%u bm:%X rxpbl:%u txpbl:%d\n",
                   bus_cfg->en_lpi,
                   bus_cfg->write_requests,
                   bus_cfg->read_requests,
                   bus_cfg->burst_map,
                   bus_cfg->rx_pbl,
                   bus_cfg->tx_pbl);

        return 0;
}

static int dwceqos_open(struct net_device *ndev)
{
        struct net_local *lp = netdev_priv(ndev);
        int res;

        dwceqos_reset_state(lp);
        res = dwceqos_descriptor_init(lp);
        if (res) {
                netdev_err(ndev, "Unable to allocate DMA memory, rc %d\n", res);
                return res;
        }
        netdev_reset_queue(ndev);

        /* The dwceqos reset state machine requires all phy clocks to complete,
         * hence the unusual init order with phy_start first.
         */
        lp->phy_defer = true;
        phy_start(lp->phy_dev);
        dwceqos_init_hw(lp);
        napi_enable(&lp->napi);

        netif_start_queue(ndev);
        tasklet_enable(&lp->tx_bdreclaim_tasklet);

        return 0;
}

static bool dweqos_is_tx_dma_suspended(struct net_local *lp)
{
        u32 reg;

        reg = dwceqos_read(lp, REG_DWCEQOS_DMA_DEBUG_ST0);
        reg = DMA_GET_TX_STATE_CH0(reg);

        return reg == DMA_TX_CH_SUSPENDED;
}

static void dwceqos_drain_dma(struct net_local *lp)
{
        /* Wait for all pending TX buffers to be sent. Upper limit based
         * on max frame size on a 10 Mbit link.
         */
        size_t limit = (DWCEQOS_TX_DCNT * 1250) / 100;

        while (!dweqos_is_tx_dma_suspended(lp) && limit--)
                usleep_range(100, 200);
}

static int dwceqos_stop(struct net_device *ndev)
{
        struct net_local *lp = netdev_priv(ndev);

        tasklet_disable(&lp->tx_bdreclaim_tasklet);
        napi_disable(&lp->napi);

        /* Stop all tx before we drain the tx dma. */
        netif_tx_lock_bh(lp->ndev);
        netif_stop_queue(ndev);
        netif_tx_unlock_bh(lp->ndev);

        dwceqos_drain_dma(lp);
        dwceqos_reset_hw(lp);
        phy_stop(lp->phy_dev);

        dwceqos_descriptor_free(lp);

        return 0;
}

static void dwceqos_dmadesc_set_ctx(struct net_local *lp,
                                    unsigned short gso_size)
{
        struct dwceqos_dma_desc *dd = &lp->tx_descs[lp->tx_next];

        dd->des0 = 0;
        dd->des1 = 0;
        dd->des2 = gso_size;
        dd->des3 = DWCEQOS_DMA_TDES3_CTXT | DWCEQOS_DMA_TDES3_TCMSSV;

        lp->tx_next = (lp->tx_next + 1) % DWCEQOS_TX_DCNT;
}

static void dwceqos_tx_poll_demand(struct net_local *lp)
{
        dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_TXDESC_TAIL,
                      lp->tx_descs_tail_addr);
}

struct dwceqos_tx {
        size_t nr_descriptors;
        size_t initial_descriptor;
        size_t last_descriptor;
        size_t prev_gso_size;
        size_t network_header_len;
};

static void dwceqos_tx_prepare(struct sk_buff *skb, struct net_local *lp,
                               struct dwceqos_tx *tx)
{
        size_t n = 1;
        size_t i;

        if (skb_is_gso(skb) && skb_shinfo(skb)->gso_size != lp->gso_size)
                ++n;

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

                n +=  (skb_frag_size(frag) + BYTES_PER_DMA_DESC - 1) /
                       BYTES_PER_DMA_DESC;
        }

        tx->nr_descriptors = n;
        tx->initial_descriptor = lp->tx_next;
        tx->last_descriptor = lp->tx_next;
        tx->prev_gso_size = lp->gso_size;

        tx->network_header_len = skb_transport_offset(skb);
        if (skb_is_gso(skb))
                tx->network_header_len += tcp_hdrlen(skb);
}

static int dwceqos_tx_linear(struct sk_buff *skb, struct net_local *lp,
                             struct dwceqos_tx *tx)
{
        struct ring_desc *rd;
        struct dwceqos_dma_desc *dd;
        size_t payload_len;
        dma_addr_t dma_handle;

        if (skb_is_gso(skb) && skb_shinfo(skb)->gso_size != lp->gso_size) {
                dwceqos_dmadesc_set_ctx(lp, skb_shinfo(skb)->gso_size);
                lp->gso_size = skb_shinfo(skb)->gso_size;
        }

        dma_handle = dma_map_single(lp->ndev->dev.parent, skb->data,
                                    skb_headlen(skb), DMA_TO_DEVICE);

        if (dma_mapping_error(lp->ndev->dev.parent, dma_handle)) {
                netdev_err(lp->ndev, "TX DMA Mapping error\n");
                return -ENOMEM;
        }

        rd = &lp->tx_skb[lp->tx_next];
        dd = &lp->tx_descs[lp->tx_next];

        rd->skb = NULL;
        rd->len = skb_headlen(skb);
        rd->mapping = dma_handle;

        /* Set up DMA Descriptor */
        dd->des0 = dma_handle;

        if (skb_is_gso(skb)) {
                payload_len = skb_headlen(skb) - tx->network_header_len;

                if (payload_len)
                        dd->des1 = dma_handle + tx->network_header_len;
                dd->des2 = tx->network_header_len |
                        DWCEQOS_DMA_DES2_B2L(payload_len);
                dd->des3 = DWCEQOS_DMA_TDES3_TSE |
                        DWCEQOS_DMA_DES3_THL((tcp_hdrlen(skb) / 4)) |
                        (skb->len - tx->network_header_len);
        } else {
                dd->des1 = 0;
                dd->des2 = skb_headlen(skb);
                dd->des3 = skb->len;

                switch (skb->ip_summed) {
                case CHECKSUM_PARTIAL:
                        dd->des3 |= DWCEQOS_DMA_TDES3_CA;
                case CHECKSUM_NONE:
                case CHECKSUM_UNNECESSARY:
                case CHECKSUM_COMPLETE:
                default:
                        break;
                }
        }

        dd->des3 |= DWCEQOS_DMA_TDES3_FD;
        if (lp->tx_next  != tx->initial_descriptor)
                dd->des3 |= DWCEQOS_DMA_TDES3_OWN;

        tx->last_descriptor = lp->tx_next;
        lp->tx_next = (lp->tx_next + 1) % DWCEQOS_TX_DCNT;

        return 0;
}

static int dwceqos_tx_frags(struct sk_buff *skb, struct net_local *lp,
                            struct dwceqos_tx *tx)
{
        struct ring_desc *rd = NULL;
        struct dwceqos_dma_desc *dd;
        dma_addr_t dma_handle;
        size_t i;

        /* Setup more ring and DMA descriptor if the packet is fragmented */
        for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                size_t frag_size;
                size_t consumed_size;

                /* Map DMA Area */
                dma_handle = skb_frag_dma_map(lp->ndev->dev.parent, frag, 0,
                                              skb_frag_size(frag),
                                              DMA_TO_DEVICE);
                if (dma_mapping_error(lp->ndev->dev.parent, dma_handle)) {
                        netdev_err(lp->ndev, "DMA Mapping error\n");
                        return -ENOMEM;
                }

                /* order-3 fragments span more than one descriptor. */
                frag_size = skb_frag_size(frag);
                consumed_size = 0;
                while (consumed_size < frag_size) {
                        size_t dma_size = min_t(size_t, 16376,
                                                frag_size - consumed_size);

                        rd = &lp->tx_skb[lp->tx_next];
                        memset(rd, 0, sizeof(*rd));

                        dd = &lp->tx_descs[lp->tx_next];

                        /* Set DMA Descriptor fields */
                        dd->des0 = dma_handle + consumed_size;
                        dd->des1 = 0;
                        dd->des2 = dma_size;

                        if (skb_is_gso(skb))
                                dd->des3 = (skb->len - tx->network_header_len);
                        else
                                dd->des3 = skb->len;

                        dd->des3 |= DWCEQOS_DMA_TDES3_OWN;

                        tx->last_descriptor = lp->tx_next;
                        lp->tx_next = (lp->tx_next + 1) % DWCEQOS_TX_DCNT;
                        consumed_size += dma_size;
                }

                rd->len = skb_frag_size(frag);
                rd->mapping = dma_handle;
        }

        return 0;
}

static void dwceqos_tx_finalize(struct sk_buff *skb, struct net_local *lp,
                                struct dwceqos_tx *tx)
{
        lp->tx_descs[tx->last_descriptor].des3 |= DWCEQOS_DMA_TDES3_LD;
        lp->tx_descs[tx->last_descriptor].des2 |= DWCEQOS_DMA_TDES2_IOC;

        lp->tx_skb[tx->last_descriptor].skb = skb;

        /* Make all descriptor updates visible to the DMA before setting the
         * owner bit.
         */
        wmb();

        lp->tx_descs[tx->initial_descriptor].des3 |= DWCEQOS_DMA_TDES3_OWN;

        /* Make the owner bit visible before TX wakeup. */
        wmb();

        dwceqos_tx_poll_demand(lp);
}

static void dwceqos_tx_rollback(struct net_local *lp, struct dwceqos_tx *tx)
{
        size_t i = tx->initial_descriptor;

        while (i != lp->tx_next) {
                if (lp->tx_skb[i].mapping)
                        dma_unmap_single(lp->ndev->dev.parent,
                                         lp->tx_skb[i].mapping,
                                         lp->tx_skb[i].len,
                                         DMA_TO_DEVICE);

                lp->tx_skb[i].mapping = 0;
                lp->tx_skb[i].skb = NULL;

                memset(&lp->tx_descs[i], 0, sizeof(lp->tx_descs[i]));

                i = (i + 1) % DWCEQOS_TX_DCNT;
        }

        lp->tx_next = tx->initial_descriptor;
        lp->gso_size = tx->prev_gso_size;
}

static int dwceqos_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
        struct net_local *lp = netdev_priv(ndev);
        struct dwceqos_tx trans;
        int err;

        dwceqos_tx_prepare(skb, lp, &trans);
        if (lp->tx_free < trans.nr_descriptors) {
                netif_stop_queue(ndev);
                return NETDEV_TX_BUSY;
        }

        err = dwceqos_tx_linear(skb, lp, &trans);
        if (err)
                goto tx_error;

        err = dwceqos_tx_frags(skb, lp, &trans);
        if (err)
                goto tx_error;

        WARN_ON(lp->tx_next !=
                ((trans.initial_descriptor + trans.nr_descriptors) %
                 DWCEQOS_TX_DCNT));

        spin_lock_bh(&lp->tx_lock);
        lp->tx_free -= trans.nr_descriptors;
        dwceqos_tx_finalize(skb, lp, &trans);
        netdev_sent_queue(ndev, skb->len);
        spin_unlock_bh(&lp->tx_lock);

        ndev->trans_start = jiffies;
        return 0;

tx_error:
        dwceqos_tx_rollback(lp, &trans);
        dev_kfree_skb(skb);
        return 0;
}

/* Set MAC address and then update HW accordingly */
static int dwceqos_set_mac_address(struct net_device *ndev, void *addr)
{
        struct net_local *lp = netdev_priv(ndev);
        struct sockaddr *hwaddr = (struct sockaddr *)addr;

        if (netif_running(ndev))
                return -EBUSY;

        if (!is_valid_ether_addr(hwaddr->sa_data))
                return -EADDRNOTAVAIL;

        memcpy(ndev->dev_addr, hwaddr->sa_data, ndev->addr_len);

        dwceqos_set_umac_addr(lp, lp->ndev->dev_addr, 0);
        return 0;
}

static void dwceqos_tx_timeout(struct net_device *ndev)
{
        struct net_local *lp = netdev_priv(ndev);

        queue_work(lp->txtimeout_handler_wq, &lp->txtimeout_reinit);
}

static void dwceqos_set_umac_addr(struct net_local *lp, unsigned char *addr,
                                  unsigned int reg_n)
{
        unsigned long data;

        data = (addr[5] << 8) | addr[4];
        dwceqos_write(lp, DWCEQOS_ADDR_HIGH(reg_n),
                      data | DWCEQOS_MAC_MAC_ADDR_HI_EN);
        data = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0];
        dwceqos_write(lp, DWCEQOS_ADDR_LOW(reg_n), data);
}

static void dwceqos_disable_umac_addr(struct net_local *lp, unsigned int reg_n)
{
        /* Do not disable MAC address 0 */
        if (reg_n != 0)
                dwceqos_write(lp, DWCEQOS_ADDR_HIGH(reg_n), 0);
}

static void dwceqos_set_rx_mode(struct net_device *ndev)
{
        struct net_local *lp = netdev_priv(ndev);
        u32 regval = 0;
        u32 mc_filter[2];
        int reg = 1;
        struct netdev_hw_addr *ha;
        unsigned int max_mac_addr;

        max_mac_addr = DWCEQOS_MAX_PERFECT_ADDRESSES(lp->feature1);

        if (ndev->flags & IFF_PROMISC) {
                regval = DWCEQOS_MAC_PKT_FILT_PR;
        } else if (((netdev_mc_count(ndev) > DWCEQOS_HASH_TABLE_SIZE) ||
                                (ndev->flags & IFF_ALLMULTI))) {
                regval = DWCEQOS_MAC_PKT_FILT_PM;
                dwceqos_write(lp, REG_DWCEQOS_HASTABLE_LO, 0xffffffff);
                dwceqos_write(lp, REG_DWCEQOS_HASTABLE_HI, 0xffffffff);
        } else if (!netdev_mc_empty(ndev)) {
                regval = DWCEQOS_MAC_PKT_FILT_HMC;
                memset(mc_filter, 0, sizeof(mc_filter));
                netdev_for_each_mc_addr(ha, ndev) {
                        /* The upper 6 bits of the calculated CRC are used to
                         * index the contens of the hash table
                         */
                        int bit_nr = bitrev32(~crc32_le(~0, ha->addr, 6)) >> 26;
                        /* The most significant bit determines the register
                         * to use (H/L) while the other 5 bits determine
                         * the bit within the register.
                         */
                        mc_filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
                }
                dwceqos_write(lp, REG_DWCEQOS_HASTABLE_LO, mc_filter[0]);
                dwceqos_write(lp, REG_DWCEQOS_HASTABLE_HI, mc_filter[1]);
        }
        if (netdev_uc_count(ndev) > max_mac_addr) {
                regval |= DWCEQOS_MAC_PKT_FILT_PR;
        } else {
                netdev_for_each_uc_addr(ha, ndev) {
                        dwceqos_set_umac_addr(lp, ha->addr, reg);
                        reg++;
                }
                for (; reg < DWCEQOS_MAX_PERFECT_ADDRESSES(lp->feature1); reg++)
                        dwceqos_disable_umac_addr(lp, reg);
        }
        dwceqos_write(lp, REG_DWCEQOS_MAC_PKT_FILT, regval);
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void dwceqos_poll_controller(struct net_device *ndev)
{
        disable_irq(ndev->irq);
        dwceqos_interrupt(ndev->irq, ndev);
        enable_irq(ndev->irq);
}
#endif

static void dwceqos_read_mmc_counters(struct net_local *lp, u32 rx_mask,
                                      u32 tx_mask)
{
        if (tx_mask & BIT(27))
                lp->mmc_counters.txlpitranscntr +=
                        dwceqos_read(lp, DWC_MMC_TXLPITRANSCNTR);
        if (tx_mask & BIT(26))
                lp->mmc_counters.txpiuscntr +=
                        dwceqos_read(lp, DWC_MMC_TXLPIUSCNTR);
        if (tx_mask & BIT(25))
                lp->mmc_counters.txoversize_g +=
                        dwceqos_read(lp, DWC_MMC_TXOVERSIZE_G);
        if (tx_mask & BIT(24))
                lp->mmc_counters.txvlanpackets_g +=
                        dwceqos_read(lp, DWC_MMC_TXVLANPACKETS_G);
        if (tx_mask & BIT(23))
                lp->mmc_counters.txpausepackets +=
                        dwceqos_read(lp, DWC_MMC_TXPAUSEPACKETS);
        if (tx_mask & BIT(22))
                lp->mmc_counters.txexcessdef +=
                        dwceqos_read(lp, DWC_MMC_TXEXCESSDEF);
        if (tx_mask & BIT(21))
                lp->mmc_counters.txpacketcount_g +=
                        dwceqos_read(lp, DWC_MMC_TXPACKETCOUNT_G);
        if (tx_mask & BIT(20))
                lp->mmc_counters.txoctetcount_g +=
                        dwceqos_read(lp, DWC_MMC_TXOCTETCOUNT_G);
        if (tx_mask & BIT(19))
                lp->mmc_counters.txcarriererror +=
                        dwceqos_read(lp, DWC_MMC_TXCARRIERERROR);
        if (tx_mask & BIT(18))
                lp->mmc_counters.txexcesscol +=
                        dwceqos_read(lp, DWC_MMC_TXEXCESSCOL);
        if (tx_mask & BIT(17))
                lp->mmc_counters.txlatecol +=
                        dwceqos_read(lp, DWC_MMC_TXLATECOL);
        if (tx_mask & BIT(16))
                lp->mmc_counters.txdeferred +=
                        dwceqos_read(lp, DWC_MMC_TXDEFERRED);
        if (tx_mask & BIT(15))
                lp->mmc_counters.txmulticol_g +=
                        dwceqos_read(lp, DWC_MMC_TXMULTICOL_G);
        if (tx_mask & BIT(14))
                lp->mmc_counters.txsinglecol_g +=
                        dwceqos_read(lp, DWC_MMC_TXSINGLECOL_G);
        if (tx_mask & BIT(13))
                lp->mmc_counters.txunderflowerror +=
                        dwceqos_read(lp, DWC_MMC_TXUNDERFLOWERROR);
        if (tx_mask & BIT(12))
                lp->mmc_counters.txbroadcastpackets_gb +=
                        dwceqos_read(lp, DWC_MMC_TXBROADCASTPACKETS_GB);
        if (tx_mask & BIT(11))
                lp->mmc_counters.txmulticastpackets_gb +=
                        dwceqos_read(lp, DWC_MMC_TXMULTICASTPACKETS_GB);
        if (tx_mask & BIT(10))
                lp->mmc_counters.txunicastpackets_gb +=
                        dwceqos_read(lp, DWC_MMC_TXUNICASTPACKETS_GB);
        if (tx_mask & BIT(9))
                lp->mmc_counters.tx1024tomaxoctets_gb +=
                        dwceqos_read(lp, DWC_MMC_TX1024TOMAXOCTETS_GB);
        if (tx_mask & BIT(8))
                lp->mmc_counters.tx512to1023octets_gb +=
                        dwceqos_read(lp, DWC_MMC_TX512TO1023OCTETS_GB);
        if (tx_mask & BIT(7))
                lp->mmc_counters.tx256to511octets_gb +=
                        dwceqos_read(lp, DWC_MMC_TX256TO511OCTETS_GB);
        if (tx_mask & BIT(6))
                lp->mmc_counters.tx128to255octets_gb +=
                        dwceqos_read(lp, DWC_MMC_TX128TO255OCTETS_GB);
        if (tx_mask & BIT(5))
                lp->mmc_counters.tx65to127octets_gb +=
                        dwceqos_read(lp, DWC_MMC_TX65TO127OCTETS_GB);
        if (tx_mask & BIT(4))
                lp->mmc_counters.tx64octets_gb +=
                        dwceqos_read(lp, DWC_MMC_TX64OCTETS_GB);
        if (tx_mask & BIT(3))
                lp->mmc_counters.txmulticastpackets_g +=
                        dwceqos_read(lp, DWC_MMC_TXMULTICASTPACKETS_G);
        if (tx_mask & BIT(2))
                lp->mmc_counters.txbroadcastpackets_g +=
                        dwceqos_read(lp, DWC_MMC_TXBROADCASTPACKETS_G);
        if (tx_mask & BIT(1))
                lp->mmc_counters.txpacketcount_gb +=
                        dwceqos_read(lp, DWC_MMC_TXPACKETCOUNT_GB);
        if (tx_mask & BIT(0))
                lp->mmc_counters.txoctetcount_gb +=
                        dwceqos_read(lp, DWC_MMC_TXOCTETCOUNT_GB);

        if (rx_mask & BIT(27))
                lp->mmc_counters.rxlpitranscntr +=
                        dwceqos_read(lp, DWC_MMC_RXLPITRANSCNTR);
        if (rx_mask & BIT(26))
                lp->mmc_counters.rxlpiuscntr +=
                        dwceqos_read(lp, DWC_MMC_RXLPIUSCNTR);
        if (rx_mask & BIT(25))
                lp->mmc_counters.rxctrlpackets_g +=
                        dwceqos_read(lp, DWC_MMC_RXCTRLPACKETS_G);
        if (rx_mask & BIT(24))
                lp->mmc_counters.rxrcverror +=
                        dwceqos_read(lp, DWC_MMC_RXRCVERROR);
        if (rx_mask & BIT(23))
                lp->mmc_counters.rxwatchdog +=
                        dwceqos_read(lp, DWC_MMC_RXWATCHDOG);
        if (rx_mask & BIT(22))
                lp->mmc_counters.rxvlanpackets_gb +=
                        dwceqos_read(lp, DWC_MMC_RXVLANPACKETS_GB);
        if (rx_mask & BIT(21))
                lp->mmc_counters.rxfifooverflow +=
                        dwceqos_read(lp, DWC_MMC_RXFIFOOVERFLOW);
        if (rx_mask & BIT(20))
                lp->mmc_counters.rxpausepackets +=
                        dwceqos_read(lp, DWC_MMC_RXPAUSEPACKETS);
        if (rx_mask & BIT(19))
                lp->mmc_counters.rxoutofrangetype +=
                        dwceqos_read(lp, DWC_MMC_RXOUTOFRANGETYPE);
        if (rx_mask & BIT(18))
                lp->mmc_counters.rxlengtherror +=
                        dwceqos_read(lp, DWC_MMC_RXLENGTHERROR);
        if (rx_mask & BIT(17))
                lp->mmc_counters.rxunicastpackets_g +=
                        dwceqos_read(lp, DWC_MMC_RXUNICASTPACKETS_G);
        if (rx_mask & BIT(16))
                lp->mmc_counters.rx1024tomaxoctets_gb +=
                        dwceqos_read(lp, DWC_MMC_RX1024TOMAXOCTETS_GB);
        if (rx_mask & BIT(15))
                lp->mmc_counters.rx512to1023octets_gb +=
                        dwceqos_read(lp, DWC_MMC_RX512TO1023OCTETS_GB);
        if (rx_mask & BIT(14))
                lp->mmc_counters.rx256to511octets_gb +=
                        dwceqos_read(lp, DWC_MMC_RX256TO511OCTETS_GB);
        if (rx_mask & BIT(13))
                lp->mmc_counters.rx128to255octets_gb +=
                        dwceqos_read(lp, DWC_MMC_RX128TO255OCTETS_GB);
        if (rx_mask & BIT(12))
                lp->mmc_counters.rx65to127octets_gb +=
                        dwceqos_read(lp, DWC_MMC_RX65TO127OCTETS_GB);
        if (rx_mask & BIT(11))
                lp->mmc_counters.rx64octets_gb +=
                        dwceqos_read(lp, DWC_MMC_RX64OCTETS_GB);
        if (rx_mask & BIT(10))
                lp->mmc_counters.rxoversize_g +=
                        dwceqos_read(lp, DWC_MMC_RXOVERSIZE_G);
        if (rx_mask & BIT(9))
                lp->mmc_counters.rxundersize_g +=
                        dwceqos_read(lp, DWC_MMC_RXUNDERSIZE_G);
        if (rx_mask & BIT(8))
                lp->mmc_counters.rxjabbererror +=
                        dwceqos_read(lp, DWC_MMC_RXJABBERERROR);
        if (rx_mask & BIT(7))
                lp->mmc_counters.rxrunterror +=
                        dwceqos_read(lp, DWC_MMC_RXRUNTERROR);
        if (rx_mask & BIT(6))
                lp->mmc_counters.rxalignmenterror +=
                        dwceqos_read(lp, DWC_MMC_RXALIGNMENTERROR);
        if (rx_mask & BIT(5))
                lp->mmc_counters.rxcrcerror +=
                        dwceqos_read(lp, DWC_MMC_RXCRCERROR);
        if (rx_mask & BIT(4))
                lp->mmc_counters.rxmulticastpackets_g +=
                        dwceqos_read(lp, DWC_MMC_RXMULTICASTPACKETS_G);
        if (rx_mask & BIT(3))
                lp->mmc_counters.rxbroadcastpackets_g +=
                        dwceqos_read(lp, DWC_MMC_RXBROADCASTPACKETS_G);
        if (rx_mask & BIT(2))
                lp->mmc_counters.rxoctetcount_g +=
                        dwceqos_read(lp, DWC_MMC_RXOCTETCOUNT_G);
        if (rx_mask & BIT(1))
                lp->mmc_counters.rxoctetcount_gb +=
                        dwceqos_read(lp, DWC_MMC_RXOCTETCOUNT_GB);
        if (rx_mask & BIT(0))
                lp->mmc_counters.rxpacketcount_gb +=
                        dwceqos_read(lp, DWC_MMC_RXPACKETCOUNT_GB);
}

static struct rtnl_link_stats64*
dwceqos_get_stats64(struct net_device *ndev, struct rtnl_link_stats64 *s)
{
        unsigned long flags;
        struct net_local *lp = netdev_priv(ndev);
        struct dwceqos_mmc_counters *hwstats = &lp->mmc_counters;

        spin_lock_irqsave(&lp->stats_lock, flags);
        dwceqos_read_mmc_counters(lp, lp->mmc_rx_counters_mask,
                                  lp->mmc_tx_counters_mask);
        spin_unlock_irqrestore(&lp->stats_lock, flags);

        s->rx_packets = hwstats->rxpacketcount_gb;
        s->rx_bytes = hwstats->rxoctetcount_gb;
        s->rx_errors = hwstats->rxpacketcount_gb -
                hwstats->rxbroadcastpackets_g -
                hwstats->rxmulticastpackets_g -
                hwstats->rxunicastpackets_g;
        s->multicast = hwstats->rxmulticastpackets_g;
        s->rx_length_errors = hwstats->rxlengtherror;
        s->rx_crc_errors = hwstats->rxcrcerror;
        s->rx_fifo_errors = hwstats->rxfifooverflow;

        s->tx_packets = hwstats->txpacketcount_gb;
        s->tx_bytes = hwstats->txoctetcount_gb;

        if (lp->mmc_tx_counters_mask & BIT(21))
                s->tx_errors = hwstats->txpacketcount_gb -
                        hwstats->txpacketcount_g;
        else
                s->tx_errors = hwstats->txunderflowerror +
                        hwstats->txcarriererror;

        return s;
}

static int
dwceqos_get_settings(struct net_device *ndev, struct ethtool_cmd *ecmd)
{
        struct net_local *lp = netdev_priv(ndev);
        struct phy_device *phydev = lp->phy_dev;

        if (!phydev)
                return -ENODEV;

        return phy_ethtool_gset(phydev, ecmd);
}

static int
dwceqos_set_settings(struct net_device *ndev, struct ethtool_cmd *ecmd)
{
        struct net_local *lp = netdev_priv(ndev);
        struct phy_device *phydev = lp->phy_dev;

        if (!phydev)
                return -ENODEV;

        return phy_ethtool_sset(phydev, ecmd);
}

static void
dwceqos_get_drvinfo(struct net_device *ndev, struct ethtool_drvinfo *ed)
{
        const struct net_local *lp = netdev_priv(ndev);

        strcpy(ed->driver, lp->pdev->dev.driver->name);
        strcpy(ed->version, DRIVER_VERSION);
}

static void dwceqos_get_pauseparam(struct net_device *ndev,
                                   struct ethtool_pauseparam *pp)
{
        const struct net_local *lp = netdev_priv(ndev);

        pp->autoneg = lp->flowcontrol.autoneg;
        pp->tx_pause = lp->flowcontrol.tx;
        pp->rx_pause = lp->flowcontrol.rx;
}

static int dwceqos_set_pauseparam(struct net_device *ndev,
                                  struct ethtool_pauseparam *pp)
{
        struct net_local *lp = netdev_priv(ndev);
        int ret = 0;

        lp->flowcontrol.autoneg = pp->autoneg;
        if (pp->autoneg) {
                lp->phy_dev->advertising |= ADVERTISED_Pause;
                lp->phy_dev->advertising |= ADVERTISED_Asym_Pause;
        } else {
                lp->phy_dev->advertising &= ~ADVERTISED_Pause;
                lp->phy_dev->advertising &= ~ADVERTISED_Asym_Pause;
                lp->flowcontrol.rx = pp->rx_pause;
                lp->flowcontrol.tx = pp->tx_pause;
        }

        if (netif_running(ndev))
                ret = phy_start_aneg(lp->phy_dev);

        return ret;
}

static void dwceqos_get_strings(struct net_device *ndev, u32 stringset,
                                u8 *data)
{
        size_t i;

        if (stringset != ETH_SS_STATS)
                return;

        for (i = 0; i < ARRAY_SIZE(dwceqos_ethtool_stats); ++i) {
                memcpy(data, dwceqos_ethtool_stats[i].stat_name,
                       ETH_GSTRING_LEN);
                data += ETH_GSTRING_LEN;
        }
}

static void dwceqos_get_ethtool_stats(struct net_device *ndev,
                                      struct ethtool_stats *stats, u64 *data)
{
        struct net_local *lp = netdev_priv(ndev);
        unsigned long flags;
        size_t i;
        u8 *mmcstat = (u8 *)&lp->mmc_counters;

        spin_lock_irqsave(&lp->stats_lock, flags);
        dwceqos_read_mmc_counters(lp, lp->mmc_rx_counters_mask,
                                  lp->mmc_tx_counters_mask);
        spin_unlock_irqrestore(&lp->stats_lock, flags);

        for (i = 0; i < ARRAY_SIZE(dwceqos_ethtool_stats); ++i) {
                memcpy(data,
                       mmcstat + dwceqos_ethtool_stats[i].offset,
                       sizeof(u64));
                data++;
        }
}

static int dwceqos_get_sset_count(struct net_device *ndev, int sset)
{
        if (sset == ETH_SS_STATS)
                return ARRAY_SIZE(dwceqos_ethtool_stats);

        return -EOPNOTSUPP;
}

static void dwceqos_get_regs(struct net_device *dev, struct ethtool_regs *regs,
                             void *space)
{
        const struct net_local *lp = netdev_priv(dev);
        u32 *reg_space = (u32 *)space;
        int reg_offset;
        int reg_ix = 0;

        /* MAC registers */
        for (reg_offset = START_MAC_REG_OFFSET;
                reg_offset <= MAX_DMA_REG_OFFSET; reg_offset += 4) {
                reg_space[reg_ix] = dwceqos_read(lp, reg_offset);
                reg_ix++;
        }
        /* MTL registers */
        for (reg_offset = START_MTL_REG_OFFSET;
                reg_offset <= MAX_MTL_REG_OFFSET; reg_offset += 4) {
                reg_space[reg_ix] = dwceqos_read(lp, reg_offset);
                reg_ix++;
        }

        /* DMA registers */
        for (reg_offset = START_DMA_REG_OFFSET;
                reg_offset <= MAX_DMA_REG_OFFSET; reg_offset += 4) {
                reg_space[reg_ix] = dwceqos_read(lp, reg_offset);
                reg_ix++;
        }

        BUG_ON(4 * reg_ix > REG_SPACE_SIZE);
}

static int dwceqos_get_regs_len(struct net_device *dev)
{
        return REG_SPACE_SIZE;
}

static inline const char *dwceqos_get_rx_lpi_state(u32 lpi_ctrl)
{
        return (lpi_ctrl & DWCEQOS_MAC_LPI_CTRL_STATUS_RLPIST) ? "on" : "off";
}

static inline const char *dwceqos_get_tx_lpi_state(u32 lpi_ctrl)
{
        return (lpi_ctrl & DWCEQOS_MAC_LPI_CTRL_STATUS_TLPIST) ? "on" : "off";
}

static int dwceqos_get_eee(struct net_device *ndev, struct ethtool_eee *edata)
{
        struct net_local *lp = netdev_priv(ndev);
        u32 lpi_status;
        u32 lpi_enabled;

        if (!(lp->feature0 & DWCEQOS_MAC_HW_FEATURE0_EEESEL))
                return -EOPNOTSUPP;

        edata->eee_active  = lp->eee_active;
        edata->eee_enabled = lp->eee_enabled;
        edata->tx_lpi_timer = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_ENTRY_TIMER);
        lpi_status = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS);
        lpi_enabled = !!(lpi_status & DWCEQOS_MAC_LPI_CTRL_STATUS_LIPTXA);
        edata->tx_lpi_enabled = lpi_enabled;

        if (netif_msg_hw(lp)) {
                u32 regval;

                regval = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS);

                netdev_info(lp->ndev, "MAC LPI State: RX:%s TX:%s\n",
                            dwceqos_get_rx_lpi_state(regval),
                            dwceqos_get_tx_lpi_state(regval));
        }

        return phy_ethtool_get_eee(lp->phy_dev, edata);
}

static int dwceqos_set_eee(struct net_device *ndev, struct ethtool_eee *edata)
{
        struct net_local *lp = netdev_priv(ndev);
        u32 regval;
        unsigned long flags;

        if (!(lp->feature0 & DWCEQOS_MAC_HW_FEATURE0_EEESEL))
                return -EOPNOTSUPP;

        if (edata->eee_enabled && !lp->eee_active)
                return -EOPNOTSUPP;

        if (edata->tx_lpi_enabled) {
                if (edata->tx_lpi_timer < DWCEQOS_LPI_TIMER_MIN ||
                    edata->tx_lpi_timer > DWCEQOS_LPI_TIMER_MAX)
                        return -EINVAL;
        }

        lp->eee_enabled = edata->eee_enabled;

        if (edata->eee_enabled && edata->tx_lpi_enabled) {
                dwceqos_write(lp, REG_DWCEQOS_MAC_LPI_ENTRY_TIMER,
                              edata->tx_lpi_timer);

                spin_lock_irqsave(&lp->hw_lock, flags);
                regval = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS);
                regval |= DWCEQOS_LPI_CTRL_ENABLE_EEE;
                if (lp->en_tx_lpi_clockgating)
                        regval |= DWCEQOS_MAC_LPI_CTRL_STATUS_LPITCSE;
                dwceqos_write(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS, regval);
                spin_unlock_irqrestore(&lp->hw_lock, flags);
        } else {
                spin_lock_irqsave(&lp->hw_lock, flags);
                regval = dwceqos_read(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS);
                regval &= ~DWCEQOS_LPI_CTRL_ENABLE_EEE;
                dwceqos_write(lp, REG_DWCEQOS_MAC_LPI_CTRL_STATUS, regval);
                spin_unlock_irqrestore(&lp->hw_lock, flags);
        }

        return phy_ethtool_set_eee(lp->phy_dev, edata);
}

static u32 dwceqos_get_msglevel(struct net_device *ndev)
{
        const struct net_local *lp = netdev_priv(ndev);

        return lp->msg_enable;
}

static void dwceqos_set_msglevel(struct net_device *ndev, u32 msglevel)
{
        struct net_local *lp = netdev_priv(ndev);

        lp->msg_enable = msglevel;
}

static struct ethtool_ops dwceqos_ethtool_ops = {
        .get_settings   = dwceqos_get_settings,
        .set_settings   = dwceqos_set_settings,
        .get_drvinfo    = dwceqos_get_drvinfo,
        .get_link       = ethtool_op_get_link,
        .get_pauseparam = dwceqos_get_pauseparam,
        .set_pauseparam = dwceqos_set_pauseparam,
        .get_strings    = dwceqos_get_strings,
        .get_ethtool_stats = dwceqos_get_ethtool_stats,
        .get_sset_count = dwceqos_get_sset_count,
        .get_regs       = dwceqos_get_regs,
        .get_regs_len   = dwceqos_get_regs_len,
        .get_eee        = dwceqos_get_eee,
        .set_eee        = dwceqos_set_eee,
        .get_msglevel   = dwceqos_get_msglevel,
        .set_msglevel   = dwceqos_set_msglevel,
};

static struct net_device_ops netdev_ops = {
        .ndo_open               = dwceqos_open,
        .ndo_stop               = dwceqos_stop,
        .ndo_start_xmit         = dwceqos_start_xmit,
        .ndo_set_rx_mode        = dwceqos_set_rx_mode,
        .ndo_set_mac_address    = dwceqos_set_mac_address,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = dwceqos_poll_controller,
#endif
        .ndo_do_ioctl           = dwceqos_ioctl,
        .ndo_tx_timeout         = dwceqos_tx_timeout,
        .ndo_get_stats64        = dwceqos_get_stats64,
};

static const struct of_device_id dwceq_of_match[] = {
        { .compatible = "snps,dwc-qos-ethernet-4.10", },
        {}
};
MODULE_DEVICE_TABLE(of, dwceq_of_match);

static int dwceqos_probe(struct platform_device *pdev)
{
        struct resource *r_mem = NULL;
        struct net_device *ndev;
        struct net_local *lp;
        int ret = -ENXIO;

        r_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!r_mem) {
                dev_err(&pdev->dev, "no IO resource defined.\n");
                return -ENXIO;
        }

        ndev = alloc_etherdev(sizeof(*lp));
        if (!ndev) {
                dev_err(&pdev->dev, "etherdev allocation failed.\n");
                return -ENOMEM;
        }

        SET_NETDEV_DEV(ndev, &pdev->dev);

        lp = netdev_priv(ndev);
        lp->ndev = ndev;
        lp->pdev = pdev;
        lp->msg_enable = netif_msg_init(debug, DWCEQOS_MSG_DEFAULT);

        spin_lock_init(&lp->tx_lock);
        spin_lock_init(&lp->hw_lock);
        spin_lock_init(&lp->stats_lock);

        lp->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
        if (IS_ERR(lp->apb_pclk)) {
                dev_err(&pdev->dev, "apb_pclk clock not found.\n");
                ret = PTR_ERR(lp->apb_pclk);
                goto err_out_free_netdev;
        }

        ret = clk_prepare_enable(lp->apb_pclk);
        if (ret) {
                dev_err(&pdev->dev, "Unable to enable APER clock.\n");
                goto err_out_free_netdev;
        }

        lp->baseaddr = devm_ioremap_resource(&pdev->dev, r_mem);
        if (IS_ERR(lp->baseaddr)) {
                dev_err(&pdev->dev, "failed to map baseaddress.\n");
                ret = PTR_ERR(lp->baseaddr);
                goto err_out_clk_dis_aper;
        }

        ndev->irq = platform_get_irq(pdev, 0);
        ndev->watchdog_timeo = DWCEQOS_TX_TIMEOUT * HZ;
        ndev->netdev_ops = &netdev_ops;
        ndev->ethtool_ops = &dwceqos_ethtool_ops;
        ndev->base_addr = r_mem->start;

        dwceqos_get_hwfeatures(lp);
        dwceqos_mdio_set_csr(lp);

        ndev->hw_features = NETIF_F_SG;

        if (lp->feature1 & DWCEQOS_MAC_HW_FEATURE1_TSOEN)
                ndev->hw_features |= NETIF_F_TSO | NETIF_F_TSO6;

        if (lp->feature0 & DWCEQOS_MAC_HW_FEATURE0_TXCOESEL)
                ndev->hw_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;

        if (lp->feature0 & DWCEQOS_MAC_HW_FEATURE0_RXCOESEL)
                ndev->hw_features |= NETIF_F_RXCSUM;

        ndev->features = ndev->hw_features;

        netif_napi_add(ndev, &lp->napi, dwceqos_rx_poll, NAPI_POLL_WEIGHT);

        ret = register_netdev(ndev);
        if (ret) {
                dev_err(&pdev->dev, "Cannot register net device, aborting.\n");
                goto err_out_clk_dis_aper;
        }

        lp->phy_ref_clk = devm_clk_get(&pdev->dev, "phy_ref_clk");
        if (IS_ERR(lp->phy_ref_clk)) {
                dev_err(&pdev->dev, "phy_ref_clk clock not found.\n");
                ret = PTR_ERR(lp->phy_ref_clk);
                goto err_out_unregister_netdev;
        }

        ret = clk_prepare_enable(lp->phy_ref_clk);
        if (ret) {
                dev_err(&pdev->dev, "Unable to enable device clock.\n");
                goto err_out_unregister_netdev;
        }

        lp->phy_node = of_parse_phandle(lp->pdev->dev.of_node,
                                                "phy-handle", 0);
        if (!lp->phy_node && of_phy_is_fixed_link(lp->pdev->dev.of_node)) {
                ret = of_phy_register_fixed_link(lp->pdev->dev.of_node);
                if (ret < 0) {
                        dev_err(&pdev->dev, "invalid fixed-link");
                        goto err_out_unregister_netdev;
                }

                lp->phy_node = of_node_get(lp->pdev->dev.of_node);
        }

        ret = of_get_phy_mode(lp->pdev->dev.of_node);
        if (ret < 0) {
                dev_err(&lp->pdev->dev, "error in getting phy i/f\n");
                goto err_out_unregister_clk_notifier;
        }

        lp->phy_interface = ret;

        ret = dwceqos_mii_init(lp);
        if (ret) {
                dev_err(&lp->pdev->dev, "error in dwceqos_mii_init\n");
                goto err_out_unregister_clk_notifier;
        }

        ret = dwceqos_mii_probe(ndev);
        if (ret != 0) {
                netdev_err(ndev, "mii_probe fail.\n");
                ret = -ENXIO;
                goto err_out_unregister_clk_notifier;
        }

        dwceqos_set_umac_addr(lp, lp->ndev->dev_addr, 0);

        tasklet_init(&lp->tx_bdreclaim_tasklet, dwceqos_tx_reclaim,
                     (unsigned long)ndev);
        tasklet_disable(&lp->tx_bdreclaim_tasklet);

        lp->txtimeout_handler_wq = create_singlethread_workqueue(DRIVER_NAME);
        INIT_WORK(&lp->txtimeout_reinit, dwceqos_reinit_for_txtimeout);

        platform_set_drvdata(pdev, ndev);
        ret = dwceqos_probe_config_dt(pdev);
        if (ret) {
                dev_err(&lp->pdev->dev, "Unable to retrieve DT, error %d\n",
                        ret);
                goto err_out_unregister_clk_notifier;
        }
        dev_info(&lp->pdev->dev, "pdev->id %d, baseaddr 0x%08lx, irq %d\n",
                 pdev->id, ndev->base_addr, ndev->irq);

        ret = devm_request_irq(&pdev->dev, ndev->irq, &dwceqos_interrupt, 0,
                               ndev->name, ndev);
        if (ret) {
                dev_err(&lp->pdev->dev, "Unable to request IRQ %d, error %d\n",
                        ndev->irq, ret);
                goto err_out_unregister_clk_notifier;
        }

        if (netif_msg_probe(lp))
                netdev_dbg(ndev, "net_local@%p\n", lp);

        return 0;

err_out_unregister_clk_notifier:
        clk_disable_unprepare(lp->phy_ref_clk);
err_out_unregister_netdev:
        unregister_netdev(ndev);
err_out_clk_dis_aper:
        clk_disable_unprepare(lp->apb_pclk);
err_out_free_netdev:
        of_node_put(lp->phy_node);
        free_netdev(ndev);
        platform_set_drvdata(pdev, NULL);
        return ret;
}

static int dwceqos_remove(struct platform_device *pdev)
{
        struct net_device *ndev = platform_get_drvdata(pdev);
        struct net_local *lp;

        if (ndev) {
                lp = netdev_priv(ndev);

                if (lp->phy_dev)
                        phy_disconnect(lp->phy_dev);
                mdiobus_unregister(lp->mii_bus);
                mdiobus_free(lp->mii_bus);

                unregister_netdev(ndev);

                clk_disable_unprepare(lp->phy_ref_clk);
                clk_disable_unprepare(lp->apb_pclk);

                free_netdev(ndev);
        }

        return 0;
}

static struct platform_driver dwceqos_driver = {