ASoC: wm8904: harmless underflow in wm8904_put_deemph()

[mirror_ubuntu-zesty-kernel.git] / drivers / net / ethernet / marvell / mvneta.c

/*
 * Driver for Marvell NETA network card for Armada XP and Armada 370 SoCs.
 *
 * Copyright (C) 2012 Marvell
 *
 * Rami Rosen <rosenr@marvell.com>
 * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/platform_device.h>
#include <linux/skbuff.h>
#include <linux/inetdevice.h>
#include <linux/mbus.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/if_vlan.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <linux/io.h>
#include <net/tso.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/of_address.h>
#include <linux/phy.h>
#include <linux/clk.h>

/* Registers */
#define MVNETA_RXQ_CONFIG_REG(q)                (0x1400 + ((q) << 2))
#define      MVNETA_RXQ_HW_BUF_ALLOC            BIT(1)
#define      MVNETA_RXQ_PKT_OFFSET_ALL_MASK     (0xf    << 8)
#define      MVNETA_RXQ_PKT_OFFSET_MASK(offs)   ((offs) << 8)
#define MVNETA_RXQ_THRESHOLD_REG(q)             (0x14c0 + ((q) << 2))
#define      MVNETA_RXQ_NON_OCCUPIED(v)         ((v) << 16)
#define MVNETA_RXQ_BASE_ADDR_REG(q)             (0x1480 + ((q) << 2))
#define MVNETA_RXQ_SIZE_REG(q)                  (0x14a0 + ((q) << 2))
#define      MVNETA_RXQ_BUF_SIZE_SHIFT          19
#define      MVNETA_RXQ_BUF_SIZE_MASK           (0x1fff << 19)
#define MVNETA_RXQ_STATUS_REG(q)                (0x14e0 + ((q) << 2))
#define      MVNETA_RXQ_OCCUPIED_ALL_MASK       0x3fff
#define MVNETA_RXQ_STATUS_UPDATE_REG(q)         (0x1500 + ((q) << 2))
#define      MVNETA_RXQ_ADD_NON_OCCUPIED_SHIFT  16
#define      MVNETA_RXQ_ADD_NON_OCCUPIED_MAX    255
#define MVNETA_PORT_RX_RESET                    0x1cc0
#define      MVNETA_PORT_RX_DMA_RESET           BIT(0)
#define MVNETA_PHY_ADDR                         0x2000
#define      MVNETA_PHY_ADDR_MASK               0x1f
#define MVNETA_MBUS_RETRY                       0x2010
#define MVNETA_UNIT_INTR_CAUSE                  0x2080
#define MVNETA_UNIT_CONTROL                     0x20B0
#define      MVNETA_PHY_POLLING_ENABLE          BIT(1)
#define MVNETA_WIN_BASE(w)                      (0x2200 + ((w) << 3))
#define MVNETA_WIN_SIZE(w)                      (0x2204 + ((w) << 3))
#define MVNETA_WIN_REMAP(w)                     (0x2280 + ((w) << 2))
#define MVNETA_BASE_ADDR_ENABLE                 0x2290
#define MVNETA_PORT_CONFIG                      0x2400
#define      MVNETA_UNI_PROMISC_MODE            BIT(0)
#define      MVNETA_DEF_RXQ(q)                  ((q) << 1)
#define      MVNETA_DEF_RXQ_ARP(q)              ((q) << 4)
#define      MVNETA_TX_UNSET_ERR_SUM            BIT(12)
#define      MVNETA_DEF_RXQ_TCP(q)              ((q) << 16)
#define      MVNETA_DEF_RXQ_UDP(q)              ((q) << 19)
#define      MVNETA_DEF_RXQ_BPDU(q)             ((q) << 22)
#define      MVNETA_RX_CSUM_WITH_PSEUDO_HDR     BIT(25)
#define      MVNETA_PORT_CONFIG_DEFL_VALUE(q)   (MVNETA_DEF_RXQ(q)       | \
                                                 MVNETA_DEF_RXQ_ARP(q)   | \
                                                 MVNETA_DEF_RXQ_TCP(q)   | \
                                                 MVNETA_DEF_RXQ_UDP(q)   | \
                                                 MVNETA_DEF_RXQ_BPDU(q)  | \
                                                 MVNETA_TX_UNSET_ERR_SUM | \
                                                 MVNETA_RX_CSUM_WITH_PSEUDO_HDR)
#define MVNETA_PORT_CONFIG_EXTEND                0x2404
#define MVNETA_MAC_ADDR_LOW                      0x2414
#define MVNETA_MAC_ADDR_HIGH                     0x2418
#define MVNETA_SDMA_CONFIG                       0x241c
#define      MVNETA_SDMA_BRST_SIZE_16            4
#define      MVNETA_RX_BRST_SZ_MASK(burst)       ((burst) << 1)
#define      MVNETA_RX_NO_DATA_SWAP              BIT(4)
#define      MVNETA_TX_NO_DATA_SWAP              BIT(5)
#define      MVNETA_DESC_SWAP                    BIT(6)
#define      MVNETA_TX_BRST_SZ_MASK(burst)       ((burst) << 22)
#define MVNETA_PORT_STATUS                       0x2444
#define      MVNETA_TX_IN_PRGRS                  BIT(1)
#define      MVNETA_TX_FIFO_EMPTY                BIT(8)
#define MVNETA_RX_MIN_FRAME_SIZE                 0x247c
#define MVNETA_SERDES_CFG                        0x24A0
#define      MVNETA_SGMII_SERDES_PROTO           0x0cc7
#define      MVNETA_QSGMII_SERDES_PROTO          0x0667
#define MVNETA_TYPE_PRIO                         0x24bc
#define      MVNETA_FORCE_UNI                    BIT(21)
#define MVNETA_TXQ_CMD_1                         0x24e4
#define MVNETA_TXQ_CMD                           0x2448
#define      MVNETA_TXQ_DISABLE_SHIFT            8
#define      MVNETA_TXQ_ENABLE_MASK              0x000000ff
#define MVNETA_GMAC_CLOCK_DIVIDER                0x24f4
#define      MVNETA_GMAC_1MS_CLOCK_ENABLE        BIT(31)
#define MVNETA_ACC_MODE                          0x2500
#define MVNETA_CPU_MAP(cpu)                      (0x2540 + ((cpu) << 2))
#define      MVNETA_CPU_RXQ_ACCESS_ALL_MASK      0x000000ff
#define      MVNETA_CPU_TXQ_ACCESS_ALL_MASK      0x0000ff00
#define MVNETA_RXQ_TIME_COAL_REG(q)              (0x2580 + ((q) << 2))

/* Exception Interrupt Port/Queue Cause register */

#define MVNETA_INTR_NEW_CAUSE                    0x25a0
#define MVNETA_INTR_NEW_MASK                     0x25a4

/* bits  0..7  = TXQ SENT, one bit per queue.
 * bits  8..15 = RXQ OCCUP, one bit per queue.
 * bits 16..23 = RXQ FREE, one bit per queue.
 * bit  29 = OLD_REG_SUM, see old reg ?
 * bit  30 = TX_ERR_SUM, one bit for 4 ports
 * bit  31 = MISC_SUM,   one bit for 4 ports
 */
#define      MVNETA_TX_INTR_MASK(nr_txqs)        (((1 << nr_txqs) - 1) << 0)
#define      MVNETA_TX_INTR_MASK_ALL             (0xff << 0)
#define      MVNETA_RX_INTR_MASK(nr_rxqs)        (((1 << nr_rxqs) - 1) << 8)
#define      MVNETA_RX_INTR_MASK_ALL             (0xff << 8)
#define      MVNETA_MISCINTR_INTR_MASK           BIT(31)

#define MVNETA_INTR_OLD_CAUSE                    0x25a8
#define MVNETA_INTR_OLD_MASK                     0x25ac

/* Data Path Port/Queue Cause Register */
#define MVNETA_INTR_MISC_CAUSE                   0x25b0
#define MVNETA_INTR_MISC_MASK                    0x25b4

#define      MVNETA_CAUSE_PHY_STATUS_CHANGE      BIT(0)
#define      MVNETA_CAUSE_LINK_CHANGE            BIT(1)
#define      MVNETA_CAUSE_PTP                    BIT(4)

#define      MVNETA_CAUSE_INTERNAL_ADDR_ERR      BIT(7)
#define      MVNETA_CAUSE_RX_OVERRUN             BIT(8)
#define      MVNETA_CAUSE_RX_CRC_ERROR           BIT(9)
#define      MVNETA_CAUSE_RX_LARGE_PKT           BIT(10)
#define      MVNETA_CAUSE_TX_UNDERUN             BIT(11)
#define      MVNETA_CAUSE_PRBS_ERR               BIT(12)
#define      MVNETA_CAUSE_PSC_SYNC_CHANGE        BIT(13)
#define      MVNETA_CAUSE_SERDES_SYNC_ERR        BIT(14)

#define      MVNETA_CAUSE_BMU_ALLOC_ERR_SHIFT    16
#define      MVNETA_CAUSE_BMU_ALLOC_ERR_ALL_MASK   (0xF << MVNETA_CAUSE_BMU_ALLOC_ERR_SHIFT)
#define      MVNETA_CAUSE_BMU_ALLOC_ERR_MASK(pool) (1 << (MVNETA_CAUSE_BMU_ALLOC_ERR_SHIFT + (pool)))

#define      MVNETA_CAUSE_TXQ_ERROR_SHIFT        24
#define      MVNETA_CAUSE_TXQ_ERROR_ALL_MASK     (0xFF << MVNETA_CAUSE_TXQ_ERROR_SHIFT)
#define      MVNETA_CAUSE_TXQ_ERROR_MASK(q)      (1 << (MVNETA_CAUSE_TXQ_ERROR_SHIFT + (q)))

#define MVNETA_INTR_ENABLE                       0x25b8
#define      MVNETA_TXQ_INTR_ENABLE_ALL_MASK     0x0000ff00
#define      MVNETA_RXQ_INTR_ENABLE_ALL_MASK     0xff000000  // note: neta says it's 0x000000FF

#define MVNETA_RXQ_CMD                           0x2680
#define      MVNETA_RXQ_DISABLE_SHIFT            8
#define      MVNETA_RXQ_ENABLE_MASK              0x000000ff
#define MVETH_TXQ_TOKEN_COUNT_REG(q)             (0x2700 + ((q) << 4))
#define MVETH_TXQ_TOKEN_CFG_REG(q)               (0x2704 + ((q) << 4))
#define MVNETA_GMAC_CTRL_0                       0x2c00
#define      MVNETA_GMAC_MAX_RX_SIZE_SHIFT       2
#define      MVNETA_GMAC_MAX_RX_SIZE_MASK        0x7ffc
#define      MVNETA_GMAC0_PORT_ENABLE            BIT(0)
#define MVNETA_GMAC_CTRL_2                       0x2c08
#define      MVNETA_GMAC2_INBAND_AN_ENABLE       BIT(0)
#define      MVNETA_GMAC2_PCS_ENABLE             BIT(3)
#define      MVNETA_GMAC2_PORT_RGMII             BIT(4)
#define      MVNETA_GMAC2_PORT_RESET             BIT(6)
#define MVNETA_GMAC_STATUS                       0x2c10
#define      MVNETA_GMAC_LINK_UP                 BIT(0)
#define      MVNETA_GMAC_SPEED_1000              BIT(1)
#define      MVNETA_GMAC_SPEED_100               BIT(2)
#define      MVNETA_GMAC_FULL_DUPLEX             BIT(3)
#define      MVNETA_GMAC_RX_FLOW_CTRL_ENABLE     BIT(4)
#define      MVNETA_GMAC_TX_FLOW_CTRL_ENABLE     BIT(5)
#define      MVNETA_GMAC_RX_FLOW_CTRL_ACTIVE     BIT(6)
#define      MVNETA_GMAC_TX_FLOW_CTRL_ACTIVE     BIT(7)
#define MVNETA_GMAC_AUTONEG_CONFIG               0x2c0c
#define      MVNETA_GMAC_FORCE_LINK_DOWN         BIT(0)
#define      MVNETA_GMAC_FORCE_LINK_PASS         BIT(1)
#define      MVNETA_GMAC_INBAND_AN_ENABLE        BIT(2)
#define      MVNETA_GMAC_CONFIG_MII_SPEED        BIT(5)
#define      MVNETA_GMAC_CONFIG_GMII_SPEED       BIT(6)
#define      MVNETA_GMAC_AN_SPEED_EN             BIT(7)
#define      MVNETA_GMAC_AN_FLOW_CTRL_EN         BIT(11)
#define      MVNETA_GMAC_CONFIG_FULL_DUPLEX      BIT(12)
#define      MVNETA_GMAC_AN_DUPLEX_EN            BIT(13)
#define MVNETA_MIB_COUNTERS_BASE                 0x3080
#define      MVNETA_MIB_LATE_COLLISION           0x7c
#define MVNETA_DA_FILT_SPEC_MCAST                0x3400
#define MVNETA_DA_FILT_OTH_MCAST                 0x3500
#define MVNETA_DA_FILT_UCAST_BASE                0x3600
#define MVNETA_TXQ_BASE_ADDR_REG(q)              (0x3c00 + ((q) << 2))
#define MVNETA_TXQ_SIZE_REG(q)                   (0x3c20 + ((q) << 2))
#define      MVNETA_TXQ_SENT_THRESH_ALL_MASK     0x3fff0000
#define      MVNETA_TXQ_SENT_THRESH_MASK(coal)   ((coal) << 16)
#define MVNETA_TXQ_UPDATE_REG(q)                 (0x3c60 + ((q) << 2))
#define      MVNETA_TXQ_DEC_SENT_SHIFT           16
#define MVNETA_TXQ_STATUS_REG(q)                 (0x3c40 + ((q) << 2))
#define      MVNETA_TXQ_SENT_DESC_SHIFT          16
#define      MVNETA_TXQ_SENT_DESC_MASK           0x3fff0000
#define MVNETA_PORT_TX_RESET                     0x3cf0
#define      MVNETA_PORT_TX_DMA_RESET            BIT(0)
#define MVNETA_TX_MTU                            0x3e0c
#define MVNETA_TX_TOKEN_SIZE                     0x3e14
#define      MVNETA_TX_TOKEN_SIZE_MAX            0xffffffff
#define MVNETA_TXQ_TOKEN_SIZE_REG(q)             (0x3e40 + ((q) << 2))
#define      MVNETA_TXQ_TOKEN_SIZE_MAX           0x7fffffff

#define MVNETA_CAUSE_TXQ_SENT_DESC_ALL_MASK      0xff

/* Descriptor ring Macros */
#define MVNETA_QUEUE_NEXT_DESC(q, index)        \
        (((index) < (q)->last_desc) ? ((index) + 1) : 0)

/* Various constants */

/* Coalescing */
#define MVNETA_TXDONE_COAL_PKTS         1
#define MVNETA_RX_COAL_PKTS             32
#define MVNETA_RX_COAL_USEC             100

/* The two bytes Marvell header. Either contains a special value used
 * by Marvell switches when a specific hardware mode is enabled (not
 * supported by this driver) or is filled automatically by zeroes on
 * the RX side. Those two bytes being at the front of the Ethernet
 * header, they allow to have the IP header aligned on a 4 bytes
 * boundary automatically: the hardware skips those two bytes on its
 * own.
 */
#define MVNETA_MH_SIZE                  2

#define MVNETA_VLAN_TAG_LEN             4

#define MVNETA_CPU_D_CACHE_LINE_SIZE    32
#define MVNETA_TX_CSUM_MAX_SIZE         9800
#define MVNETA_ACC_MODE_EXT             1

/* Timeout constants */
#define MVNETA_TX_DISABLE_TIMEOUT_MSEC  1000
#define MVNETA_RX_DISABLE_TIMEOUT_MSEC  1000
#define MVNETA_TX_FIFO_EMPTY_TIMEOUT    10000

#define MVNETA_TX_MTU_MAX               0x3ffff

/* TSO header size */
#define TSO_HEADER_SIZE 128

/* Max number of Rx descriptors */
#define MVNETA_MAX_RXD 128

/* Max number of Tx descriptors */
#define MVNETA_MAX_TXD 532

/* Max number of allowed TCP segments for software TSO */
#define MVNETA_MAX_TSO_SEGS 100

#define MVNETA_MAX_SKB_DESCS (MVNETA_MAX_TSO_SEGS * 2 + MAX_SKB_FRAGS)

/* descriptor aligned size */
#define MVNETA_DESC_ALIGNED_SIZE        32

#define MVNETA_RX_PKT_SIZE(mtu) \
        ALIGN((mtu) + MVNETA_MH_SIZE + MVNETA_VLAN_TAG_LEN + \
              ETH_HLEN + ETH_FCS_LEN,                        \
              MVNETA_CPU_D_CACHE_LINE_SIZE)

#define IS_TSO_HEADER(txq, addr) \
        ((addr >= txq->tso_hdrs_phys) && \
         (addr < txq->tso_hdrs_phys + txq->size * TSO_HEADER_SIZE))

#define MVNETA_RX_BUF_SIZE(pkt_size)   ((pkt_size) + NET_SKB_PAD)

struct mvneta_pcpu_stats {
        struct  u64_stats_sync syncp;
        u64     rx_packets;
        u64     rx_bytes;
        u64     tx_packets;
        u64     tx_bytes;
};

struct mvneta_port {
        int pkt_size;
        unsigned int frag_size;
        void __iomem *base;
        struct mvneta_rx_queue *rxqs;
        struct mvneta_tx_queue *txqs;
        struct net_device *dev;

        u32 cause_rx_tx;
        struct napi_struct napi;

        /* Core clock */
        struct clk *clk;
        u8 mcast_count[256];
        u16 tx_ring_size;
        u16 rx_ring_size;
        struct mvneta_pcpu_stats *stats;

        struct mii_bus *mii_bus;
        struct phy_device *phy_dev;
        phy_interface_t phy_interface;
        struct device_node *phy_node;
        unsigned int link;
        unsigned int duplex;
        unsigned int speed;
        unsigned int tx_csum_limit;
        int use_inband_status:1;
};

/* The mvneta_tx_desc and mvneta_rx_desc structures describe the
 * layout of the transmit and reception DMA descriptors, and their
 * layout is therefore defined by the hardware design
 */

#define MVNETA_TX_L3_OFF_SHIFT  0
#define MVNETA_TX_IP_HLEN_SHIFT 8
#define MVNETA_TX_L4_UDP        BIT(16)
#define MVNETA_TX_L3_IP6        BIT(17)
#define MVNETA_TXD_IP_CSUM      BIT(18)
#define MVNETA_TXD_Z_PAD        BIT(19)
#define MVNETA_TXD_L_DESC       BIT(20)
#define MVNETA_TXD_F_DESC       BIT(21)
#define MVNETA_TXD_FLZ_DESC     (MVNETA_TXD_Z_PAD  | \
                                 MVNETA_TXD_L_DESC | \
                                 MVNETA_TXD_F_DESC)
#define MVNETA_TX_L4_CSUM_FULL  BIT(30)
#define MVNETA_TX_L4_CSUM_NOT   BIT(31)

#define MVNETA_RXD_ERR_CRC              0x0
#define MVNETA_RXD_ERR_SUMMARY          BIT(16)
#define MVNETA_RXD_ERR_OVERRUN          BIT(17)
#define MVNETA_RXD_ERR_LEN              BIT(18)
#define MVNETA_RXD_ERR_RESOURCE         (BIT(17) | BIT(18))
#define MVNETA_RXD_ERR_CODE_MASK        (BIT(17) | BIT(18))
#define MVNETA_RXD_L3_IP4               BIT(25)
#define MVNETA_RXD_FIRST_LAST_DESC      (BIT(26) | BIT(27))
#define MVNETA_RXD_L4_CSUM_OK           BIT(30)

#if defined(__LITTLE_ENDIAN)
struct mvneta_tx_desc {
        u32  command;           /* Options used by HW for packet transmitting.*/
        u16  reserverd1;        /* csum_l4 (for future use)             */
        u16  data_size;         /* Data size of transmitted packet in bytes */
        u32  buf_phys_addr;     /* Physical addr of transmitted buffer  */
        u32  reserved2;         /* hw_cmd - (for future use, PMT)       */
        u32  reserved3[4];      /* Reserved - (for future use)          */
};

struct mvneta_rx_desc {
        u32  status;            /* Info about received packet           */
        u16  reserved1;         /* pnc_info - (for future use, PnC)     */
        u16  data_size;         /* Size of received packet in bytes     */

        u32  buf_phys_addr;     /* Physical address of the buffer       */
        u32  reserved2;         /* pnc_flow_id  (for future use, PnC)   */

        u32  buf_cookie;        /* cookie for access to RX buffer in rx path */
        u16  reserved3;         /* prefetch_cmd, for future use         */
        u16  reserved4;         /* csum_l4 - (for future use, PnC)      */

        u32  reserved5;         /* pnc_extra PnC (for future use, PnC)  */
        u32  reserved6;         /* hw_cmd (for future use, PnC and HWF) */
};
#else
struct mvneta_tx_desc {
        u16  data_size;         /* Data size of transmitted packet in bytes */
        u16  reserverd1;        /* csum_l4 (for future use)             */
        u32  command;           /* Options used by HW for packet transmitting.*/
        u32  reserved2;         /* hw_cmd - (for future use, PMT)       */
        u32  buf_phys_addr;     /* Physical addr of transmitted buffer  */
        u32  reserved3[4];      /* Reserved - (for future use)          */
};

struct mvneta_rx_desc {
        u16  data_size;         /* Size of received packet in bytes     */
        u16  reserved1;         /* pnc_info - (for future use, PnC)     */
        u32  status;            /* Info about received packet           */

        u32  reserved2;         /* pnc_flow_id  (for future use, PnC)   */
        u32  buf_phys_addr;     /* Physical address of the buffer       */

        u16  reserved4;         /* csum_l4 - (for future use, PnC)      */
        u16  reserved3;         /* prefetch_cmd, for future use         */
        u32  buf_cookie;        /* cookie for access to RX buffer in rx path */

        u32  reserved5;         /* pnc_extra PnC (for future use, PnC)  */
        u32  reserved6;         /* hw_cmd (for future use, PnC and HWF) */
};
#endif

struct mvneta_tx_queue {
        /* Number of this TX queue, in the range 0-7 */
        u8 id;

        /* Number of TX DMA descriptors in the descriptor ring */
        int size;

        /* Number of currently used TX DMA descriptor in the
         * descriptor ring
         */
        int count;
        int tx_stop_threshold;
        int tx_wake_threshold;

        /* Array of transmitted skb */
        struct sk_buff **tx_skb;

        /* Index of last TX DMA descriptor that was inserted */
        int txq_put_index;

        /* Index of the TX DMA descriptor to be cleaned up */
        int txq_get_index;

        u32 done_pkts_coal;

        /* Virtual address of the TX DMA descriptors array */
        struct mvneta_tx_desc *descs;

        /* DMA address of the TX DMA descriptors array */
        dma_addr_t descs_phys;

        /* Index of the last TX DMA descriptor */
        int last_desc;

        /* Index of the next TX DMA descriptor to process */
        int next_desc_to_proc;

        /* DMA buffers for TSO headers */
        char *tso_hdrs;

        /* DMA address of TSO headers */
        dma_addr_t tso_hdrs_phys;
};

struct mvneta_rx_queue {
        /* rx queue number, in the range 0-7 */
        u8 id;

        /* num of rx descriptors in the rx descriptor ring */
        int size;

        /* counter of times when mvneta_refill() failed */
        int missed;

        u32 pkts_coal;
        u32 time_coal;

        /* Virtual address of the RX DMA descriptors array */
        struct mvneta_rx_desc *descs;

        /* DMA address of the RX DMA descriptors array */
        dma_addr_t descs_phys;

        /* Index of the last RX DMA descriptor */
        int last_desc;

        /* Index of the next RX DMA descriptor to process */
        int next_desc_to_proc;
};

/* The hardware supports eight (8) rx queues, but we are only allowing
 * the first one to be used. Therefore, let's just allocate one queue.
 */
static int rxq_number = 1;
static int txq_number = 8;

static int rxq_def;

static int rx_copybreak __read_mostly = 256;

#define MVNETA_DRIVER_NAME "mvneta"
#define MVNETA_DRIVER_VERSION "1.0"

/* Utility/helper methods */

/* Write helper method */
static void mvreg_write(struct mvneta_port *pp, u32 offset, u32 data)
{
        writel(data, pp->base + offset);
}

/* Read helper method */
static u32 mvreg_read(struct mvneta_port *pp, u32 offset)
{
        return readl(pp->base + offset);
}

/* Increment txq get counter */
static void mvneta_txq_inc_get(struct mvneta_tx_queue *txq)
{
        txq->txq_get_index++;
        if (txq->txq_get_index == txq->size)
                txq->txq_get_index = 0;
}

/* Increment txq put counter */
static void mvneta_txq_inc_put(struct mvneta_tx_queue *txq)
{
        txq->txq_put_index++;
        if (txq->txq_put_index == txq->size)
                txq->txq_put_index = 0;
}


/* Clear all MIB counters */
static void mvneta_mib_counters_clear(struct mvneta_port *pp)
{
        int i;
        u32 dummy;

        /* Perform dummy reads from MIB counters */
        for (i = 0; i < MVNETA_MIB_LATE_COLLISION; i += 4)
                dummy = mvreg_read(pp, (MVNETA_MIB_COUNTERS_BASE + i));
}

/* Get System Network Statistics */
struct rtnl_link_stats64 *mvneta_get_stats64(struct net_device *dev,
                                             struct rtnl_link_stats64 *stats)
{
        struct mvneta_port *pp = netdev_priv(dev);
        unsigned int start;
        int cpu;

        for_each_possible_cpu(cpu) {
                struct mvneta_pcpu_stats *cpu_stats;
                u64 rx_packets;
                u64 rx_bytes;
                u64 tx_packets;
                u64 tx_bytes;

                cpu_stats = per_cpu_ptr(pp->stats, cpu);
                do {
                        start = u64_stats_fetch_begin_irq(&cpu_stats->syncp);
                        rx_packets = cpu_stats->rx_packets;
                        rx_bytes   = cpu_stats->rx_bytes;
                        tx_packets = cpu_stats->tx_packets;
                        tx_bytes   = cpu_stats->tx_bytes;
                } while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, start));

                stats->rx_packets += rx_packets;
                stats->rx_bytes   += rx_bytes;
                stats->tx_packets += tx_packets;
                stats->tx_bytes   += tx_bytes;
        }

        stats->rx_errors        = dev->stats.rx_errors;
        stats->rx_dropped       = dev->stats.rx_dropped;

        stats->tx_dropped       = dev->stats.tx_dropped;

        return stats;
}

/* Rx descriptors helper methods */

/* Checks whether the RX descriptor having this status is both the first
 * and the last descriptor for the RX packet. Each RX packet is currently
 * received through a single RX descriptor, so not having each RX
 * descriptor with its first and last bits set is an error
 */
static int mvneta_rxq_desc_is_first_last(u32 status)
{
        return (status & MVNETA_RXD_FIRST_LAST_DESC) ==
                MVNETA_RXD_FIRST_LAST_DESC;
}

/* Add number of descriptors ready to receive new packets */
static void mvneta_rxq_non_occup_desc_add(struct mvneta_port *pp,
                                          struct mvneta_rx_queue *rxq,
                                          int ndescs)
{
        /* Only MVNETA_RXQ_ADD_NON_OCCUPIED_MAX (255) descriptors can
         * be added at once
         */
        while (ndescs > MVNETA_RXQ_ADD_NON_OCCUPIED_MAX) {
                mvreg_write(pp, MVNETA_RXQ_STATUS_UPDATE_REG(rxq->id),
                            (MVNETA_RXQ_ADD_NON_OCCUPIED_MAX <<
                             MVNETA_RXQ_ADD_NON_OCCUPIED_SHIFT));
                ndescs -= MVNETA_RXQ_ADD_NON_OCCUPIED_MAX;
        }

        mvreg_write(pp, MVNETA_RXQ_STATUS_UPDATE_REG(rxq->id),
                    (ndescs << MVNETA_RXQ_ADD_NON_OCCUPIED_SHIFT));
}

/* Get number of RX descriptors occupied by received packets */
static int mvneta_rxq_busy_desc_num_get(struct mvneta_port *pp,
                                        struct mvneta_rx_queue *rxq)
{
        u32 val;

        val = mvreg_read(pp, MVNETA_RXQ_STATUS_REG(rxq->id));
        return val & MVNETA_RXQ_OCCUPIED_ALL_MASK;
}

/* Update num of rx desc called upon return from rx path or
 * from mvneta_rxq_drop_pkts().
 */
static void mvneta_rxq_desc_num_update(struct mvneta_port *pp,
                                       struct mvneta_rx_queue *rxq,
                                       int rx_done, int rx_filled)
{
        u32 val;

        if ((rx_done <= 0xff) && (rx_filled <= 0xff)) {
                val = rx_done |
                  (rx_filled << MVNETA_RXQ_ADD_NON_OCCUPIED_SHIFT);
                mvreg_write(pp, MVNETA_RXQ_STATUS_UPDATE_REG(rxq->id), val);
                return;
        }

        /* Only 255 descriptors can be added at once */
        while ((rx_done > 0) || (rx_filled > 0)) {
                if (rx_done <= 0xff) {
                        val = rx_done;
                        rx_done = 0;
                } else {
                        val = 0xff;
                        rx_done -= 0xff;
                }
                if (rx_filled <= 0xff) {
                        val |= rx_filled << MVNETA_RXQ_ADD_NON_OCCUPIED_SHIFT;
                        rx_filled = 0;
                } else {
                        val |= 0xff << MVNETA_RXQ_ADD_NON_OCCUPIED_SHIFT;
                        rx_filled -= 0xff;
                }
                mvreg_write(pp, MVNETA_RXQ_STATUS_UPDATE_REG(rxq->id), val);
        }
}

/* Get pointer to next RX descriptor to be processed by SW */
static struct mvneta_rx_desc *
mvneta_rxq_next_desc_get(struct mvneta_rx_queue *rxq)
{
        int rx_desc = rxq->next_desc_to_proc;

        rxq->next_desc_to_proc = MVNETA_QUEUE_NEXT_DESC(rxq, rx_desc);
        prefetch(rxq->descs + rxq->next_desc_to_proc);
        return rxq->descs + rx_desc;
}

/* Change maximum receive size of the port. */
static void mvneta_max_rx_size_set(struct mvneta_port *pp, int max_rx_size)
{
        u32 val;

        val =  mvreg_read(pp, MVNETA_GMAC_CTRL_0);
        val &= ~MVNETA_GMAC_MAX_RX_SIZE_MASK;
        val |= ((max_rx_size - MVNETA_MH_SIZE) / 2) <<
                MVNETA_GMAC_MAX_RX_SIZE_SHIFT;
        mvreg_write(pp, MVNETA_GMAC_CTRL_0, val);
}


/* Set rx queue offset */
static void mvneta_rxq_offset_set(struct mvneta_port *pp,
                                  struct mvneta_rx_queue *rxq,
                                  int offset)
{
        u32 val;

        val = mvreg_read(pp, MVNETA_RXQ_CONFIG_REG(rxq->id));
        val &= ~MVNETA_RXQ_PKT_OFFSET_ALL_MASK;

        /* Offset is in */
        val |= MVNETA_RXQ_PKT_OFFSET_MASK(offset >> 3);
        mvreg_write(pp, MVNETA_RXQ_CONFIG_REG(rxq->id), val);
}


/* Tx descriptors helper methods */

/* Update HW with number of TX descriptors to be sent */
static void mvneta_txq_pend_desc_add(struct mvneta_port *pp,
                                     struct mvneta_tx_queue *txq,
                                     int pend_desc)
{
        u32 val;

        /* Only 255 descriptors can be added at once ; Assume caller
         * process TX desriptors in quanta less than 256
         */
        val = pend_desc;
        mvreg_write(pp, MVNETA_TXQ_UPDATE_REG(txq->id), val);
}

/* Get pointer to next TX descriptor to be processed (send) by HW */
static struct mvneta_tx_desc *
mvneta_txq_next_desc_get(struct mvneta_tx_queue *txq)
{
        int tx_desc = txq->next_desc_to_proc;

        txq->next_desc_to_proc = MVNETA_QUEUE_NEXT_DESC(txq, tx_desc);
        return txq->descs + tx_desc;
}

/* Release the last allocated TX descriptor. Useful to handle DMA
 * mapping failures in the TX path.
 */
static void mvneta_txq_desc_put(struct mvneta_tx_queue *txq)
{
        if (txq->next_desc_to_proc == 0)
                txq->next_desc_to_proc = txq->last_desc - 1;
        else
                txq->next_desc_to_proc--;
}

/* Set rxq buf size */
static void mvneta_rxq_buf_size_set(struct mvneta_port *pp,
                                    struct mvneta_rx_queue *rxq,
                                    int buf_size)
{
        u32 val;

        val = mvreg_read(pp, MVNETA_RXQ_SIZE_REG(rxq->id));

        val &= ~MVNETA_RXQ_BUF_SIZE_MASK;
        val |= ((buf_size >> 3) << MVNETA_RXQ_BUF_SIZE_SHIFT);

        mvreg_write(pp, MVNETA_RXQ_SIZE_REG(rxq->id), val);
}

/* Disable buffer management (BM) */
static void mvneta_rxq_bm_disable(struct mvneta_port *pp,
                                  struct mvneta_rx_queue *rxq)
{
        u32 val;

        val = mvreg_read(pp, MVNETA_RXQ_CONFIG_REG(rxq->id));
        val &= ~MVNETA_RXQ_HW_BUF_ALLOC;
        mvreg_write(pp, MVNETA_RXQ_CONFIG_REG(rxq->id), val);
}

/* Start the Ethernet port RX and TX activity */
static void mvneta_port_up(struct mvneta_port *pp)
{
        int queue;
        u32 q_map;

        /* Enable all initialized TXs. */
        mvneta_mib_counters_clear(pp);
        q_map = 0;
        for (queue = 0; queue < txq_number; queue++) {
                struct mvneta_tx_queue *txq = &pp->txqs[queue];
                if (txq->descs != NULL)
                        q_map |= (1 << queue);
        }
        mvreg_write(pp, MVNETA_TXQ_CMD, q_map);

        /* Enable all initialized RXQs. */
        q_map = 0;
        for (queue = 0; queue < rxq_number; queue++) {
                struct mvneta_rx_queue *rxq = &pp->rxqs[queue];
                if (rxq->descs != NULL)
                        q_map |= (1 << queue);
        }

        mvreg_write(pp, MVNETA_RXQ_CMD, q_map);
}

/* Stop the Ethernet port activity */
static void mvneta_port_down(struct mvneta_port *pp)
{
        u32 val;
        int count;

        /* Stop Rx port activity. Check port Rx activity. */
        val = mvreg_read(pp, MVNETA_RXQ_CMD) & MVNETA_RXQ_ENABLE_MASK;

        /* Issue stop command for active channels only */
        if (val != 0)
                mvreg_write(pp, MVNETA_RXQ_CMD,
                            val << MVNETA_RXQ_DISABLE_SHIFT);

        /* Wait for all Rx activity to terminate. */
        count = 0;
        do {
                if (count++ >= MVNETA_RX_DISABLE_TIMEOUT_MSEC) {
                        netdev_warn(pp->dev,
                                    "TIMEOUT for RX stopped ! rx_queue_cmd: 0x08%x\n",
                                    val);
                        break;
                }
                mdelay(1);

                val = mvreg_read(pp, MVNETA_RXQ_CMD);
        } while (val & 0xff);

        /* Stop Tx port activity. Check port Tx activity. Issue stop
         * command for active channels only
         */
        val = (mvreg_read(pp, MVNETA_TXQ_CMD)) & MVNETA_TXQ_ENABLE_MASK;

        if (val != 0)
                mvreg_write(pp, MVNETA_TXQ_CMD,
                            (val << MVNETA_TXQ_DISABLE_SHIFT));

        /* Wait for all Tx activity to terminate. */
        count = 0;
        do {
                if (count++ >= MVNETA_TX_DISABLE_TIMEOUT_MSEC) {
                        netdev_warn(pp->dev,
                                    "TIMEOUT for TX stopped status=0x%08x\n",
                                    val);
                        break;
                }
                mdelay(1);

                /* Check TX Command reg that all Txqs are stopped */
                val = mvreg_read(pp, MVNETA_TXQ_CMD);

        } while (val & 0xff);

        /* Double check to verify that TX FIFO is empty */
        count = 0;
        do {
                if (count++ >= MVNETA_TX_FIFO_EMPTY_TIMEOUT) {
                        netdev_warn(pp->dev,
                                    "TX FIFO empty timeout status=0x08%x\n",
                                    val);
                        break;
                }
                mdelay(1);

                val = mvreg_read(pp, MVNETA_PORT_STATUS);
        } while (!(val & MVNETA_TX_FIFO_EMPTY) &&
                 (val & MVNETA_TX_IN_PRGRS));

        udelay(200);
}

/* Enable the port by setting the port enable bit of the MAC control register */
static void mvneta_port_enable(struct mvneta_port *pp)
{
        u32 val;

        /* Enable port */
        val = mvreg_read(pp, MVNETA_GMAC_CTRL_0);
        val |= MVNETA_GMAC0_PORT_ENABLE;
        mvreg_write(pp, MVNETA_GMAC_CTRL_0, val);
}

/* Disable the port and wait for about 200 usec before retuning */
static void mvneta_port_disable(struct mvneta_port *pp)
{
        u32 val;

        /* Reset the Enable bit in the Serial Control Register */
        val = mvreg_read(pp, MVNETA_GMAC_CTRL_0);
        val &= ~MVNETA_GMAC0_PORT_ENABLE;
        mvreg_write(pp, MVNETA_GMAC_CTRL_0, val);

        udelay(200);
}

/* Multicast tables methods */

/* Set all entries in Unicast MAC Table; queue==-1 means reject all */
static void mvneta_set_ucast_table(struct mvneta_port *pp, int queue)
{
        int offset;
        u32 val;

        if (queue == -1) {
                val = 0;
        } else {
                val = 0x1 | (queue << 1);
                val |= (val << 24) | (val << 16) | (val << 8);
        }

        for (offset = 0; offset <= 0xc; offset += 4)
                mvreg_write(pp, MVNETA_DA_FILT_UCAST_BASE + offset, val);
}

/* Set all entries in Special Multicast MAC Table; queue==-1 means reject all */
static void mvneta_set_special_mcast_table(struct mvneta_port *pp, int queue)
{
        int offset;
        u32 val;

        if (queue == -1) {
                val = 0;
        } else {
                val = 0x1 | (queue << 1);
                val |= (val << 24) | (val << 16) | (val << 8);
        }

        for (offset = 0; offset <= 0xfc; offset += 4)
                mvreg_write(pp, MVNETA_DA_FILT_SPEC_MCAST + offset, val);

}

/* Set all entries in Other Multicast MAC Table. queue==-1 means reject all */
static void mvneta_set_other_mcast_table(struct mvneta_port *pp, int queue)
{
        int offset;
        u32 val;

        if (queue == -1) {
                memset(pp->mcast_count, 0, sizeof(pp->mcast_count));
                val = 0;
        } else {
                memset(pp->mcast_count, 1, sizeof(pp->mcast_count));
                val = 0x1 | (queue << 1);
                val |= (val << 24) | (val << 16) | (val << 8);
        }

        for (offset = 0; offset <= 0xfc; offset += 4)
                mvreg_write(pp, MVNETA_DA_FILT_OTH_MCAST + offset, val);
}

/* This method sets defaults to the NETA port:
 *      Clears interrupt Cause and Mask registers.
 *      Clears all MAC tables.
 *      Sets defaults to all registers.
 *      Resets RX and TX descriptor rings.
 *      Resets PHY.
 * This method can be called after mvneta_port_down() to return the port
 *      settings to defaults.
 */
static void mvneta_defaults_set(struct mvneta_port *pp)
{
        int cpu;
        int queue;
        u32 val;

        /* Clear all Cause registers */
        mvreg_write(pp, MVNETA_INTR_NEW_CAUSE, 0);
        mvreg_write(pp, MVNETA_INTR_OLD_CAUSE, 0);
        mvreg_write(pp, MVNETA_INTR_MISC_CAUSE, 0);

        /* Mask all interrupts */
        mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0);
        mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0);
        mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0);
        mvreg_write(pp, MVNETA_INTR_ENABLE, 0);

        /* Enable MBUS Retry bit16 */
        mvreg_write(pp, MVNETA_MBUS_RETRY, 0x20);

        /* Set CPU queue access map - all CPUs have access to all RX
         * queues and to all TX queues
         */
        for (cpu = 0; cpu < CONFIG_NR_CPUS; cpu++)
                mvreg_write(pp, MVNETA_CPU_MAP(cpu),
                            (MVNETA_CPU_RXQ_ACCESS_ALL_MASK |
                             MVNETA_CPU_TXQ_ACCESS_ALL_MASK));

        /* Reset RX and TX DMAs */
        mvreg_write(pp, MVNETA_PORT_RX_RESET, MVNETA_PORT_RX_DMA_RESET);
        mvreg_write(pp, MVNETA_PORT_TX_RESET, MVNETA_PORT_TX_DMA_RESET);

        /* Disable Legacy WRR, Disable EJP, Release from reset */
        mvreg_write(pp, MVNETA_TXQ_CMD_1, 0);
        for (queue = 0; queue < txq_number; queue++) {
                mvreg_write(pp, MVETH_TXQ_TOKEN_COUNT_REG(queue), 0);
                mvreg_write(pp, MVETH_TXQ_TOKEN_CFG_REG(queue), 0);
        }

        mvreg_write(pp, MVNETA_PORT_TX_RESET, 0);
        mvreg_write(pp, MVNETA_PORT_RX_RESET, 0);

        /* Set Port Acceleration Mode */
        val = MVNETA_ACC_MODE_EXT;
        mvreg_write(pp, MVNETA_ACC_MODE, val);

        /* Update val of portCfg register accordingly with all RxQueue types */
        val = MVNETA_PORT_CONFIG_DEFL_VALUE(rxq_def);
        mvreg_write(pp, MVNETA_PORT_CONFIG, val);

        val = 0;
        mvreg_write(pp, MVNETA_PORT_CONFIG_EXTEND, val);
        mvreg_write(pp, MVNETA_RX_MIN_FRAME_SIZE, 64);

        /* Build PORT_SDMA_CONFIG_REG */
        val = 0;

        /* Default burst size */
        val |= MVNETA_TX_BRST_SZ_MASK(MVNETA_SDMA_BRST_SIZE_16);
        val |= MVNETA_RX_BRST_SZ_MASK(MVNETA_SDMA_BRST_SIZE_16);
        val |= MVNETA_RX_NO_DATA_SWAP | MVNETA_TX_NO_DATA_SWAP;

#if defined(__BIG_ENDIAN)
        val |= MVNETA_DESC_SWAP;
#endif

        /* Assign port SDMA configuration */
        mvreg_write(pp, MVNETA_SDMA_CONFIG, val);

        /* Disable PHY polling in hardware, since we're using the
         * kernel phylib to do this.
         */
        val = mvreg_read(pp, MVNETA_UNIT_CONTROL);
        val &= ~MVNETA_PHY_POLLING_ENABLE;
        mvreg_write(pp, MVNETA_UNIT_CONTROL, val);

        if (pp->use_inband_status) {
                val = mvreg_read(pp, MVNETA_GMAC_AUTONEG_CONFIG);
                val &= ~(MVNETA_GMAC_FORCE_LINK_PASS |
                         MVNETA_GMAC_FORCE_LINK_DOWN |
                         MVNETA_GMAC_AN_FLOW_CTRL_EN);
                val |= MVNETA_GMAC_INBAND_AN_ENABLE |
                       MVNETA_GMAC_AN_SPEED_EN |
                       MVNETA_GMAC_AN_DUPLEX_EN;
                mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG, val);
                val = mvreg_read(pp, MVNETA_GMAC_CLOCK_DIVIDER);
                val |= MVNETA_GMAC_1MS_CLOCK_ENABLE;
                mvreg_write(pp, MVNETA_GMAC_CLOCK_DIVIDER, val);
        } else {
                val = mvreg_read(pp, MVNETA_GMAC_AUTONEG_CONFIG);
                val &= ~(MVNETA_GMAC_INBAND_AN_ENABLE |
                       MVNETA_GMAC_AN_SPEED_EN |
                       MVNETA_GMAC_AN_DUPLEX_EN);
                mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG, val);
        }

        mvneta_set_ucast_table(pp, -1);
        mvneta_set_special_mcast_table(pp, -1);
        mvneta_set_other_mcast_table(pp, -1);

        /* Set port interrupt enable register - default enable all */
        mvreg_write(pp, MVNETA_INTR_ENABLE,
                    (MVNETA_RXQ_INTR_ENABLE_ALL_MASK
                     | MVNETA_TXQ_INTR_ENABLE_ALL_MASK));
}

/* Set max sizes for tx queues */
static void mvneta_txq_max_tx_size_set(struct mvneta_port *pp, int max_tx_size)

{
        u32 val, size, mtu;
        int queue;

        mtu = max_tx_size * 8;
        if (mtu > MVNETA_TX_MTU_MAX)
                mtu = MVNETA_TX_MTU_MAX;

        /* Set MTU */
        val = mvreg_read(pp, MVNETA_TX_MTU);
        val &= ~MVNETA_TX_MTU_MAX;
        val |= mtu;
        mvreg_write(pp, MVNETA_TX_MTU, val);

        /* TX token size and all TXQs token size must be larger that MTU */
        val = mvreg_read(pp, MVNETA_TX_TOKEN_SIZE);

        size = val & MVNETA_TX_TOKEN_SIZE_MAX;
        if (size < mtu) {
                size = mtu;
                val &= ~MVNETA_TX_TOKEN_SIZE_MAX;
                val |= size;
                mvreg_write(pp, MVNETA_TX_TOKEN_SIZE, val);
        }
        for (queue = 0; queue < txq_number; queue++) {
                val = mvreg_read(pp, MVNETA_TXQ_TOKEN_SIZE_REG(queue));

                size = val & MVNETA_TXQ_TOKEN_SIZE_MAX;
                if (size < mtu) {
                        size = mtu;
                        val &= ~MVNETA_TXQ_TOKEN_SIZE_MAX;
                        val |= size;
                        mvreg_write(pp, MVNETA_TXQ_TOKEN_SIZE_REG(queue), val);
                }
        }
}

/* Set unicast address */
static void mvneta_set_ucast_addr(struct mvneta_port *pp, u8 last_nibble,
                                  int queue)
{
        unsigned int unicast_reg;
        unsigned int tbl_offset;
        unsigned int reg_offset;

        /* Locate the Unicast table entry */
        last_nibble = (0xf & last_nibble);

        /* offset from unicast tbl base */
        tbl_offset = (last_nibble / 4) * 4;

        /* offset within the above reg  */
        reg_offset = last_nibble % 4;

        unicast_reg = mvreg_read(pp, (MVNETA_DA_FILT_UCAST_BASE + tbl_offset));

        if (queue == -1) {
                /* Clear accepts frame bit at specified unicast DA tbl entry */
                unicast_reg &= ~(0xff << (8 * reg_offset));
        } else {
                unicast_reg &= ~(0xff << (8 * reg_offset));
                unicast_reg |= ((0x01 | (queue << 1)) << (8 * reg_offset));
        }

        mvreg_write(pp, (MVNETA_DA_FILT_UCAST_BASE + tbl_offset), unicast_reg);
}

/* Set mac address */
static void mvneta_mac_addr_set(struct mvneta_port *pp, unsigned char *addr,
                                int queue)
{
        unsigned int mac_h;
        unsigned int mac_l;

        if (queue != -1) {
                mac_l = (addr[4] << 8) | (addr[5]);
                mac_h = (addr[0] << 24) | (addr[1] << 16) |
                        (addr[2] << 8) | (addr[3] << 0);

                mvreg_write(pp, MVNETA_MAC_ADDR_LOW, mac_l);
                mvreg_write(pp, MVNETA_MAC_ADDR_HIGH, mac_h);
        }

        /* Accept frames of this address */
        mvneta_set_ucast_addr(pp, addr[5], queue);
}

/* Set the number of packets that will be received before RX interrupt
 * will be generated by HW.
 */
static void mvneta_rx_pkts_coal_set(struct mvneta_port *pp,
                                    struct mvneta_rx_queue *rxq, u32 value)
{
        mvreg_write(pp, MVNETA_RXQ_THRESHOLD_REG(rxq->id),
                    value | MVNETA_RXQ_NON_OCCUPIED(0));
        rxq->pkts_coal = value;
}

/* Set the time delay in usec before RX interrupt will be generated by
 * HW.
 */
static void mvneta_rx_time_coal_set(struct mvneta_port *pp,
                                    struct mvneta_rx_queue *rxq, u32 value)
{
        u32 val;
        unsigned long clk_rate;

        clk_rate = clk_get_rate(pp->clk);
        val = (clk_rate / 1000000) * value;

        mvreg_write(pp, MVNETA_RXQ_TIME_COAL_REG(rxq->id), val);
        rxq->time_coal = value;
}

/* Set threshold for TX_DONE pkts coalescing */
static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp,
                                         struct mvneta_tx_queue *txq, u32 value)
{
        u32 val;

        val = mvreg_read(pp, MVNETA_TXQ_SIZE_REG(txq->id));

        val &= ~MVNETA_TXQ_SENT_THRESH_ALL_MASK;
        val |= MVNETA_TXQ_SENT_THRESH_MASK(value);

        mvreg_write(pp, MVNETA_TXQ_SIZE_REG(txq->id), val);

        txq->done_pkts_coal = value;
}

/* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */
static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc,
                                u32 phys_addr, u32 cookie)
{
        rx_desc->buf_cookie = cookie;
        rx_desc->buf_phys_addr = phys_addr;
}

/* Decrement sent descriptors counter */
static void mvneta_txq_sent_desc_dec(struct mvneta_port *pp,
                                     struct mvneta_tx_queue *txq,
                                     int sent_desc)
{
        u32 val;

        /* Only 255 TX descriptors can be updated at once */
        while (sent_desc > 0xff) {
                val = 0xff << MVNETA_TXQ_DEC_SENT_SHIFT;
                mvreg_write(pp, MVNETA_TXQ_UPDATE_REG(txq->id), val);
                sent_desc = sent_desc - 0xff;
        }

        val = sent_desc << MVNETA_TXQ_DEC_SENT_SHIFT;
        mvreg_write(pp, MVNETA_TXQ_UPDATE_REG(txq->id), val);
}

/* Get number of TX descriptors already sent by HW */
static int mvneta_txq_sent_desc_num_get(struct mvneta_port *pp,
                                        struct mvneta_tx_queue *txq)
{
        u32 val;
        int sent_desc;

        val = mvreg_read(pp, MVNETA_TXQ_STATUS_REG(txq->id));
        sent_desc = (val & MVNETA_TXQ_SENT_DESC_MASK) >>
                MVNETA_TXQ_SENT_DESC_SHIFT;

        return sent_desc;
}

/* Get number of sent descriptors and decrement counter.
 *  The number of sent descriptors is returned.
 */
static int mvneta_txq_sent_desc_proc(struct mvneta_port *pp,
                                     struct mvneta_tx_queue *txq)
{
        int sent_desc;

        /* Get number of sent descriptors */
        sent_desc = mvneta_txq_sent_desc_num_get(pp, txq);

        /* Decrement sent descriptors counter */
        if (sent_desc)
                mvneta_txq_sent_desc_dec(pp, txq, sent_desc);

        return sent_desc;
}

/* Set TXQ descriptors fields relevant for CSUM calculation */
static u32 mvneta_txq_desc_csum(int l3_offs, int l3_proto,
                                int ip_hdr_len, int l4_proto)
{
        u32 command;

        /* Fields: L3_offset, IP_hdrlen, L3_type, G_IPv4_chk,
         * G_L4_chk, L4_type; required only for checksum
         * calculation
         */
        command =  l3_offs    << MVNETA_TX_L3_OFF_SHIFT;
        command |= ip_hdr_len << MVNETA_TX_IP_HLEN_SHIFT;

        if (l3_proto == htons(ETH_P_IP))
                command |= MVNETA_TXD_IP_CSUM;
        else
                command |= MVNETA_TX_L3_IP6;

        if (l4_proto == IPPROTO_TCP)
                command |=  MVNETA_TX_L4_CSUM_FULL;
        else if (l4_proto == IPPROTO_UDP)
                command |= MVNETA_TX_L4_UDP | MVNETA_TX_L4_CSUM_FULL;
        else
                command |= MVNETA_TX_L4_CSUM_NOT;

        return command;
}


/* Display more error info */
static void mvneta_rx_error(struct mvneta_port *pp,
                            struct mvneta_rx_desc *rx_desc)
{
        u32 status = rx_desc->status;

        if (!mvneta_rxq_desc_is_first_last(status)) {
                netdev_err(pp->dev,
                           "bad rx status %08x (buffer oversize), size=%d\n",
                           status, rx_desc->data_size);
                return;
        }

        switch (status & MVNETA_RXD_ERR_CODE_MASK) {
        case MVNETA_RXD_ERR_CRC:
                netdev_err(pp->dev, "bad rx status %08x (crc error), size=%d\n",
                           status, rx_desc->data_size);
                break;
        case MVNETA_RXD_ERR_OVERRUN:
                netdev_err(pp->dev, "bad rx status %08x (overrun error), size=%d\n",
                           status, rx_desc->data_size);
                break;
        case MVNETA_RXD_ERR_LEN:
                netdev_err(pp->dev, "bad rx status %08x (max frame length error), size=%d\n",
                           status, rx_desc->data_size);
                break;
        case MVNETA_RXD_ERR_RESOURCE:
                netdev_err(pp->dev, "bad rx status %08x (resource error), size=%d\n",
                           status, rx_desc->data_size);
                break;
        }
}

/* Handle RX checksum offload based on the descriptor's status */
static void mvneta_rx_csum(struct mvneta_port *pp, u32 status,
                           struct sk_buff *skb)
{
        if ((status & MVNETA_RXD_L3_IP4) &&
            (status & MVNETA_RXD_L4_CSUM_OK)) {
                skb->csum = 0;
                skb->ip_summed = CHECKSUM_UNNECESSARY;
                return;
        }

        skb->ip_summed = CHECKSUM_NONE;
}

/* Return tx queue pointer (find last set bit) according to <cause> returned
 * form tx_done reg. <cause> must not be null. The return value is always a
 * valid queue for matching the first one found in <cause>.
 */
static struct mvneta_tx_queue *mvneta_tx_done_policy(struct mvneta_port *pp,
                                                     u32 cause)
{
        int queue = fls(cause) - 1;

        return &pp->txqs[queue];
}

/* Free tx queue skbuffs */
static void mvneta_txq_bufs_free(struct mvneta_port *pp,
                                 struct mvneta_tx_queue *txq, int num)
{
        int i;

        for (i = 0; i < num; i++) {
                struct mvneta_tx_desc *tx_desc = txq->descs +
                        txq->txq_get_index;
                struct sk_buff *skb = txq->tx_skb[txq->txq_get_index];

                mvneta_txq_inc_get(txq);

                if (!IS_TSO_HEADER(txq, tx_desc->buf_phys_addr))
                        dma_unmap_single(pp->dev->dev.parent,
                                         tx_desc->buf_phys_addr,
                                         tx_desc->data_size, DMA_TO_DEVICE);
                if (!skb)
                        continue;
                dev_kfree_skb_any(skb);
        }
}

/* Handle end of transmission */
static void mvneta_txq_done(struct mvneta_port *pp,
                           struct mvneta_tx_queue *txq)
{
        struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id);
        int tx_done;

        tx_done = mvneta_txq_sent_desc_proc(pp, txq);
        if (!tx_done)
                return;

        mvneta_txq_bufs_free(pp, txq, tx_done);

        txq->count -= tx_done;

        if (netif_tx_queue_stopped(nq)) {
                if (txq->count <= txq->tx_wake_threshold)
                        netif_tx_wake_queue(nq);
        }
}

static void *mvneta_frag_alloc(const struct mvneta_port *pp)
{
        if (likely(pp->frag_size <= PAGE_SIZE))
                return netdev_alloc_frag(pp->frag_size);
        else
                return kmalloc(pp->frag_size, GFP_ATOMIC);
}

static void mvneta_frag_free(const struct mvneta_port *pp, void *data)
{
        if (likely(pp->frag_size <= PAGE_SIZE))
                skb_free_frag(data);
        else
                kfree(data);
}

/* Refill processing */
static int mvneta_rx_refill(struct mvneta_port *pp,
                            struct mvneta_rx_desc *rx_desc)

{
        dma_addr_t phys_addr;
        void *data;

        data = mvneta_frag_alloc(pp);
        if (!data)
                return -ENOMEM;

        phys_addr = dma_map_single(pp->dev->dev.parent, data,
                                   MVNETA_RX_BUF_SIZE(pp->pkt_size),
                                   DMA_FROM_DEVICE);
        if (unlikely(dma_mapping_error(pp->dev->dev.parent, phys_addr))) {
                mvneta_frag_free(pp, data);
                return -ENOMEM;
        }

        mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data);
        return 0;
}

/* Handle tx checksum */
static u32 mvneta_skb_tx_csum(struct mvneta_port *pp, struct sk_buff *skb)
{
        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                int ip_hdr_len = 0;
                __be16 l3_proto = vlan_get_protocol(skb);
                u8 l4_proto;

                if (l3_proto == htons(ETH_P_IP)) {
                        struct iphdr *ip4h = ip_hdr(skb);

                        /* Calculate IPv4 checksum and L4 checksum */
                        ip_hdr_len = ip4h->ihl;
                        l4_proto = ip4h->protocol;
                } else if (l3_proto == htons(ETH_P_IPV6)) {
                        struct ipv6hdr *ip6h = ipv6_hdr(skb);

                        /* Read l4_protocol from one of IPv6 extra headers */
                        if (skb_network_header_len(skb) > 0)
                                ip_hdr_len = (skb_network_header_len(skb) >> 2);
                        l4_proto = ip6h->nexthdr;
                } else
                        return MVNETA_TX_L4_CSUM_NOT;

                return mvneta_txq_desc_csum(skb_network_offset(skb),
                                            l3_proto, ip_hdr_len, l4_proto);
        }

        return MVNETA_TX_L4_CSUM_NOT;
}

/* Returns rx queue pointer (find last set bit) according to causeRxTx
 * value
 */
static struct mvneta_rx_queue *mvneta_rx_policy(struct mvneta_port *pp,
                                                u32 cause)
{
        int queue = fls(cause >> 8) - 1;

        return (queue < 0 || queue >= rxq_number) ? NULL : &pp->rxqs[queue];
}

/* Drop packets received by the RXQ and free buffers */
static void mvneta_rxq_drop_pkts(struct mvneta_port *pp,
                                 struct mvneta_rx_queue *rxq)
{
        int rx_done, i;

        rx_done = mvneta_rxq_busy_desc_num_get(pp, rxq);
        for (i = 0; i < rxq->size; i++) {
                struct mvneta_rx_desc *rx_desc = rxq->descs + i;
                void *data = (void *)rx_desc->buf_cookie;

                mvneta_frag_free(pp, data);
                dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr,
                                 MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE);
        }

        if (rx_done)
                mvneta_rxq_desc_num_update(pp, rxq, rx_done, rx_done);
}

/* Main rx processing */
static int mvneta_rx(struct mvneta_port *pp, int rx_todo,
                     struct mvneta_rx_queue *rxq)
{
        struct net_device *dev = pp->dev;
        int rx_done;
        u32 rcvd_pkts = 0;
        u32 rcvd_bytes = 0;

        /* Get number of received packets */
        rx_done = mvneta_rxq_busy_desc_num_get(pp, rxq);

        if (rx_todo > rx_done)
                rx_todo = rx_done;

        rx_done = 0;

        /* Fairness NAPI loop */
        while (rx_done < rx_todo) {
                struct mvneta_rx_desc *rx_desc = mvneta_rxq_next_desc_get(rxq);
                struct sk_buff *skb;
                unsigned char *data;
                u32 rx_status;
                int rx_bytes, err;

                rx_done++;
                rx_status = rx_desc->status;
                rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE);
                data = (unsigned char *)rx_desc->buf_cookie;

                if (!mvneta_rxq_desc_is_first_last(rx_status) ||
                    (rx_status & MVNETA_RXD_ERR_SUMMARY)) {
                err_drop_frame:
                        dev->stats.rx_errors++;
                        mvneta_rx_error(pp, rx_desc);
                        /* leave the descriptor untouched */
                        continue;
                }

                if (rx_bytes <= rx_copybreak) {
                        /* better copy a small frame and not unmap the DMA region */
                        skb = netdev_alloc_skb_ip_align(dev, rx_bytes);
                        if (unlikely(!skb))
                                goto err_drop_frame;

                        dma_sync_single_range_for_cpu(dev->dev.parent,
                                                      rx_desc->buf_phys_addr,
                                                      MVNETA_MH_SIZE + NET_SKB_PAD,
                                                      rx_bytes,
                                                      DMA_FROM_DEVICE);
                        memcpy(skb_put(skb, rx_bytes),
                               data + MVNETA_MH_SIZE + NET_SKB_PAD,
                               rx_bytes);

                        skb->protocol = eth_type_trans(skb, dev);
                        mvneta_rx_csum(pp, rx_status, skb);
                        napi_gro_receive(&pp->napi, skb);

                        rcvd_pkts++;
                        rcvd_bytes += rx_bytes;

                        /* leave the descriptor and buffer untouched */
                        continue;
                }

                /* Refill processing */
                err = mvneta_rx_refill(pp, rx_desc);
                if (err) {
                        netdev_err(dev, "Linux processing - Can't refill\n");
                        rxq->missed++;
                        goto err_drop_frame;
                }

                skb = build_skb(data, pp->frag_size > PAGE_SIZE ? 0 : pp->frag_size);
                if (!skb)
                        goto err_drop_frame;

                dma_unmap_single(dev->dev.parent, rx_desc->buf_phys_addr,
                                 MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE);

                rcvd_pkts++;
                rcvd_bytes += rx_bytes;

                /* Linux processing */
                skb_reserve(skb, MVNETA_MH_SIZE + NET_SKB_PAD);
                skb_put(skb, rx_bytes);

                skb->protocol = eth_type_trans(skb, dev);

                mvneta_rx_csum(pp, rx_status, skb);

                napi_gro_receive(&pp->napi, skb);
        }

        if (rcvd_pkts) {
                struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);

                u64_stats_update_begin(&stats->syncp);
                stats->rx_packets += rcvd_pkts;
                stats->rx_bytes   += rcvd_bytes;
                u64_stats_update_end(&stats->syncp);
        }

        /* Update rxq management counters */
        mvneta_rxq_desc_num_update(pp, rxq, rx_done, rx_done);

        return rx_done;
}

static inline void
mvneta_tso_put_hdr(struct sk_buff *skb,
                   struct mvneta_port *pp, struct mvneta_tx_queue *txq)
{
        struct mvneta_tx_desc *tx_desc;
        int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);

        txq->tx_skb[txq->txq_put_index] = NULL;
        tx_desc = mvneta_txq_next_desc_get(txq);
        tx_desc->data_size = hdr_len;
        tx_desc->command = mvneta_skb_tx_csum(pp, skb);
        tx_desc->command |= MVNETA_TXD_F_DESC;
        tx_desc->buf_phys_addr = txq->tso_hdrs_phys +
                                 txq->txq_put_index * TSO_HEADER_SIZE;
        mvneta_txq_inc_put(txq);
}

static inline int
mvneta_tso_put_data(struct net_device *dev, struct mvneta_tx_queue *txq,
                    struct sk_buff *skb, char *data, int size,
                    bool last_tcp, bool is_last)
{
        struct mvneta_tx_desc *tx_desc;

        tx_desc = mvneta_txq_next_desc_get(txq);
        tx_desc->data_size = size;
        tx_desc->buf_phys_addr = dma_map_single(dev->dev.parent, data,
                                                size, DMA_TO_DEVICE);
        if (unlikely(dma_mapping_error(dev->dev.parent,
                     tx_desc->buf_phys_addr))) {
                mvneta_txq_desc_put(txq);
                return -ENOMEM;
        }

        tx_desc->command = 0;
        txq->tx_skb[txq->txq_put_index] = NULL;

        if (last_tcp) {
                /* last descriptor in the TCP packet */
                tx_desc->command = MVNETA_TXD_L_DESC;

                /* last descriptor in SKB */
                if (is_last)
                        txq->tx_skb[txq->txq_put_index] = skb;
        }
        mvneta_txq_inc_put(txq);
        return 0;
}

static int mvneta_tx_tso(struct sk_buff *skb, struct net_device *dev,
                         struct mvneta_tx_queue *txq)
{
        int total_len, data_left;
        int desc_count = 0;
        struct mvneta_port *pp = netdev_priv(dev);
        struct tso_t tso;
        int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
        int i;

        /* Count needed descriptors */
        if ((txq->count + tso_count_descs(skb)) >= txq->size)
                return 0;

        if (skb_headlen(skb) < (skb_transport_offset(skb) + tcp_hdrlen(skb))) {
                pr_info("*** Is this even  possible???!?!?\n");
                return 0;
        }

        /* Initialize the TSO handler, and prepare the first payload */
        tso_start(skb, &tso);

        total_len = skb->len - hdr_len;
        while (total_len > 0) {
                char *hdr;

                data_left = min_t(int, skb_shinfo(skb)->gso_size, total_len);
                total_len -= data_left;
                desc_count++;

                /* prepare packet headers: MAC + IP + TCP */
                hdr = txq->tso_hdrs + txq->txq_put_index * TSO_HEADER_SIZE;
                tso_build_hdr(skb, hdr, &tso, data_left, total_len == 0);

                mvneta_tso_put_hdr(skb, pp, txq);

                while (data_left > 0) {
                        int size;
                        desc_count++;

                        size = min_t(int, tso.size, data_left);

                        if (mvneta_tso_put_data(dev, txq, skb,
                                                 tso.data, size,
                                                 size == data_left,
                                                 total_len == 0))
                                goto err_release;
                        data_left -= size;

                        tso_build_data(skb, &tso, size);
                }
        }

        return desc_count;

err_release:
        /* Release all used data descriptors; header descriptors must not
         * be DMA-unmapped.
         */
        for (i = desc_count - 1; i >= 0; i--) {
                struct mvneta_tx_desc *tx_desc = txq->descs + i;
                if (!IS_TSO_HEADER(txq, tx_desc->buf_phys_addr))
                        dma_unmap_single(pp->dev->dev.parent,
                                         tx_desc->buf_phys_addr,
                                         tx_desc->data_size,
                                         DMA_TO_DEVICE);
                mvneta_txq_desc_put(txq);
        }
        return 0;
}

/* Handle tx fragmentation processing */
static int mvneta_tx_frag_process(struct mvneta_port *pp, struct sk_buff *skb,
                                  struct mvneta_tx_queue *txq)
{
        struct mvneta_tx_desc *tx_desc;
        int i, nr_frags = skb_shinfo(skb)->nr_frags;

        for (i = 0; i < nr_frags; i++) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                void *addr = page_address(frag->page.p) + frag->page_offset;

                tx_desc = mvneta_txq_next_desc_get(txq);
                tx_desc->data_size = frag->size;

                tx_desc->buf_phys_addr =
                        dma_map_single(pp->dev->dev.parent, addr,
                                       tx_desc->data_size, DMA_TO_DEVICE);

                if (dma_mapping_error(pp->dev->dev.parent,
                                      tx_desc->buf_phys_addr)) {
                        mvneta_txq_desc_put(txq);
                        goto error;
                }

                if (i == nr_frags - 1) {
                        /* Last descriptor */
                        tx_desc->command = MVNETA_TXD_L_DESC | MVNETA_TXD_Z_PAD;
                        txq->tx_skb[txq->txq_put_index] = skb;
                } else {
                        /* Descriptor in the middle: Not First, Not Last */
                        tx_desc->command = 0;
                        txq->tx_skb[txq->txq_put_index] = NULL;
                }
                mvneta_txq_inc_put(txq);
        }

        return 0;

error:
        /* Release all descriptors that were used to map fragments of
         * this packet, as well as the corresponding DMA mappings
         */
        for (i = i - 1; i >= 0; i--) {
                tx_desc = txq->descs + i;
                dma_unmap_single(pp->dev->dev.parent,
                                 tx_desc->buf_phys_addr,
                                 tx_desc->data_size,
                                 DMA_TO_DEVICE);
                mvneta_txq_desc_put(txq);
        }

        return -ENOMEM;
}

/* Main tx processing */
static int mvneta_tx(struct sk_buff *skb, struct net_device *dev)
{
        struct mvneta_port *pp = netdev_priv(dev);
        u16 txq_id = skb_get_queue_mapping(skb);
        struct mvneta_tx_queue *txq = &pp->txqs[txq_id];
        struct mvneta_tx_desc *tx_desc;
        int len = skb->len;
        int frags = 0;
        u32 tx_cmd;

        if (!netif_running(dev))
                goto out;

        if (skb_is_gso(skb)) {
                frags = mvneta_tx_tso(skb, dev, txq);
                goto out;
        }

        frags = skb_shinfo(skb)->nr_frags + 1;

        /* Get a descriptor for the first part of the packet */
        tx_desc = mvneta_txq_next_desc_get(txq);

        tx_cmd = mvneta_skb_tx_csum(pp, skb);

        tx_desc->data_size = skb_headlen(skb);

        tx_desc->buf_phys_addr = dma_map_single(dev->dev.parent, skb->data,
                                                tx_desc->data_size,
                                                DMA_TO_DEVICE);
        if (unlikely(dma_mapping_error(dev->dev.parent,
                                       tx_desc->buf_phys_addr))) {
                mvneta_txq_desc_put(txq);
                frags = 0;
                goto out;
        }

        if (frags == 1) {
                /* First and Last descriptor */
                tx_cmd |= MVNETA_TXD_FLZ_DESC;
                tx_desc->command = tx_cmd;
                txq->tx_skb[txq->txq_put_index] = skb;
                mvneta_txq_inc_put(txq);
        } else {
                /* First but not Last */
                tx_cmd |= MVNETA_TXD_F_DESC;
                txq->tx_skb[txq->txq_put_index] = NULL;
                mvneta_txq_inc_put(txq);
                tx_desc->command = tx_cmd;
                /* Continue with other skb fragments */
                if (mvneta_tx_frag_process(pp, skb, txq)) {
                        dma_unmap_single(dev->dev.parent,
                                         tx_desc->buf_phys_addr,
                                         tx_desc->data_size,
                                         DMA_TO_DEVICE);
                        mvneta_txq_desc_put(txq);
                        frags = 0;
                        goto out;
                }
        }

out:
        if (frags > 0) {
                struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);
                struct netdev_queue *nq = netdev_get_tx_queue(dev, txq_id);

                txq->count += frags;
                mvneta_txq_pend_desc_add(pp, txq, frags);

                if (txq->count >= txq->tx_stop_threshold)
                        netif_tx_stop_queue(nq);

                u64_stats_update_begin(&stats->syncp);
                stats->tx_packets++;
                stats->tx_bytes  += len;
                u64_stats_update_end(&stats->syncp);
        } else {
                dev->stats.tx_dropped++;
                dev_kfree_skb_any(skb);
        }

        return NETDEV_TX_OK;
}


/* Free tx resources, when resetting a port */
static void mvneta_txq_done_force(struct mvneta_port *pp,
                                  struct mvneta_tx_queue *txq)

{
        int tx_done = txq->count;

        mvneta_txq_bufs_free(pp, txq, tx_done);

        /* reset txq */
        txq->count = 0;
        txq->txq_put_index = 0;
        txq->txq_get_index = 0;
}

/* Handle tx done - called in softirq context. The <cause_tx_done> argument
 * must be a valid cause according to MVNETA_TXQ_INTR_MASK_ALL.
 */
static void mvneta_tx_done_gbe(struct mvneta_port *pp, u32 cause_tx_done)
{
        struct mvneta_tx_queue *txq;
        struct netdev_queue *nq;

        while (cause_tx_done) {
                txq = mvneta_tx_done_policy(pp, cause_tx_done);

                nq = netdev_get_tx_queue(pp->dev, txq->id);
                __netif_tx_lock(nq, smp_processor_id());

                if (txq->count)
                        mvneta_txq_done(pp, txq);

                __netif_tx_unlock(nq);
                cause_tx_done &= ~((1 << txq->id));
        }
}

/* Compute crc8 of the specified address, using a unique algorithm ,
 * according to hw spec, different than generic crc8 algorithm
 */
static int mvneta_addr_crc(unsigned char *addr)
{
        int crc = 0;
        int i;

        for (i = 0; i < ETH_ALEN; i++) {
                int j;

                crc = (crc ^ addr[i]) << 8;
                for (j = 7; j >= 0; j--) {
                        if (crc & (0x100 << j))
                                crc ^= 0x107 << j;
                }
        }

        return crc;
}

/* This method controls the net device special MAC multicast support.
 * The Special Multicast Table for MAC addresses supports MAC of the form
 * 0x01-00-5E-00-00-XX (where XX is between 0x00 and 0xFF).
 * The MAC DA[7:0] bits are used as a pointer to the Special Multicast
 * Table entries in the DA-Filter table. This method set the Special
 * Multicast Table appropriate entry.
 */
static void mvneta_set_special_mcast_addr(struct mvneta_port *pp,
                                          unsigned char last_byte,
                                          int queue)
{
        unsigned int smc_table_reg;
        unsigned int tbl_offset;
        unsigned int reg_offset;

        /* Register offset from SMC table base    */
        tbl_offset = (last_byte / 4);
        /* Entry offset within the above reg */
        reg_offset = last_byte % 4;

        smc_table_reg = mvreg_read(pp, (MVNETA_DA_FILT_SPEC_MCAST
                                        + tbl_offset * 4));

        if (queue == -1)
                smc_table_reg &= ~(0xff << (8 * reg_offset));
        else {
                smc_table_reg &= ~(0xff << (8 * reg_offset));
                smc_table_reg |= ((0x01 | (queue << 1)) << (8 * reg_offset));
        }

        mvreg_write(pp, MVNETA_DA_FILT_SPEC_MCAST + tbl_offset * 4,
                    smc_table_reg);
}

/* This method controls the network device Other MAC multicast support.
 * The Other Multicast Table is used for multicast of another type.
 * A CRC-8 is used as an index to the Other Multicast Table entries
 * in the DA-Filter table.
 * The method gets the CRC-8 value from the calling routine and
 * sets the Other Multicast Table appropriate entry according to the
 * specified CRC-8 .
 */
static void mvneta_set_other_mcast_addr(struct mvneta_port *pp,
                                        unsigned char crc8,
                                        int queue)
{
        unsigned int omc_table_reg;
        unsigned int tbl_offset;
        unsigned int reg_offset;

        tbl_offset = (crc8 / 4) * 4; /* Register offset from OMC table base */
        reg_offset = crc8 % 4;       /* Entry offset within the above reg   */

        omc_table_reg = mvreg_read(pp, MVNETA_DA_FILT_OTH_MCAST + tbl_offset);

        if (queue == -1) {
                /* Clear accepts frame bit at specified Other DA table entry */
                omc_table_reg &= ~(0xff << (8 * reg_offset));
        } else {
                omc_table_reg &= ~(0xff << (8 * reg_offset));
                omc_table_reg |= ((0x01 | (queue << 1)) << (8 * reg_offset));
        }

        mvreg_write(pp, MVNETA_DA_FILT_OTH_MCAST + tbl_offset, omc_table_reg);
}

/* The network device supports multicast using two tables:
 *    1) Special Multicast Table for MAC addresses of the form
 *       0x01-00-5E-00-00-XX (where XX is between 0x00 and 0xFF).
 *       The MAC DA[7:0] bits are used as a pointer to the Special Multicast
 *       Table entries in the DA-Filter table.
 *    2) Other Multicast Table for multicast of another type. A CRC-8 value
 *       is used as an index to the Other Multicast Table entries in the
 *       DA-Filter table.
 */
static int mvneta_mcast_addr_set(struct mvneta_port *pp, unsigned char *p_addr,
                                 int queue)
{
        unsigned char crc_result = 0;

        if (memcmp(p_addr, "\x01\x00\x5e\x00\x00", 5) == 0) {
                mvneta_set_special_mcast_addr(pp, p_addr[5], queue);
                return 0;
        }

        crc_result = mvneta_addr_crc(p_addr);
        if (queue == -1) {
                if (pp->mcast_count[crc_result] == 0) {
                        netdev_info(pp->dev, "No valid Mcast for crc8=0x%02x\n",
                                    crc_result);
                        return -EINVAL;
                }

                pp->mcast_count[crc_result]--;
                if (pp->mcast_count[crc_result] != 0) {
                        netdev_info(pp->dev,
                                    "After delete there are %d valid Mcast for crc8=0x%02x\n",
                                    pp->mcast_count[crc_result], crc_result);
                        return -EINVAL;
                }
        } else
                pp->mcast_count[crc_result]++;

        mvneta_set_other_mcast_addr(pp, crc_result, queue);

        return 0;
}

/* Configure Fitering mode of Ethernet port */
static void mvneta_rx_unicast_promisc_set(struct mvneta_port *pp,
                                          int is_promisc)
{
        u32 port_cfg_reg, val;

        port_cfg_reg = mvreg_read(pp, MVNETA_PORT_CONFIG);

        val = mvreg_read(pp, MVNETA_TYPE_PRIO);

        /* Set / Clear UPM bit in port configuration register */
        if (is_promisc) {
                /* Accept all Unicast addresses */
                port_cfg_reg |= MVNETA_UNI_PROMISC_MODE;
                val |= MVNETA_FORCE_UNI;
                mvreg_write(pp, MVNETA_MAC_ADDR_LOW, 0xffff);
                mvreg_write(pp, MVNETA_MAC_ADDR_HIGH, 0xffffffff);
        } else {
                /* Reject all Unicast addresses */
                port_cfg_reg &= ~MVNETA_UNI_PROMISC_MODE;
                val &= ~MVNETA_FORCE_UNI;
        }

        mvreg_write(pp, MVNETA_PORT_CONFIG, port_cfg_reg);
        mvreg_write(pp, MVNETA_TYPE_PRIO, val);
}

/* register unicast and multicast addresses */
static void mvneta_set_rx_mode(struct net_device *dev)
{
        struct mvneta_port *pp = netdev_priv(dev);
        struct netdev_hw_addr *ha;

        if (dev->flags & IFF_PROMISC) {
                /* Accept all: Multicast + Unicast */
                mvneta_rx_unicast_promisc_set(pp, 1);
                mvneta_set_ucast_table(pp, rxq_def);
                mvneta_set_special_mcast_table(pp, rxq_def);
                mvneta_set_other_mcast_table(pp, rxq_def);
        } else {
                /* Accept single Unicast */
                mvneta_rx_unicast_promisc_set(pp, 0);
                mvneta_set_ucast_table(pp, -1);
                mvneta_mac_addr_set(pp, dev->dev_addr, rxq_def);

                if (dev->flags & IFF_ALLMULTI) {
                        /* Accept all multicast */
                        mvneta_set_special_mcast_table(pp, rxq_def);
                        mvneta_set_other_mcast_table(pp, rxq_def);
                } else {
                        /* Accept only initialized multicast */
                        mvneta_set_special_mcast_table(pp, -1);
                        mvneta_set_other_mcast_table(pp, -1);

                        if (!netdev_mc_empty(dev)) {
                                netdev_for_each_mc_addr(ha, dev) {
                                        mvneta_mcast_addr_set(pp, ha->addr,
                                                              rxq_def);
                                }
                        }
                }
        }
}

/* Interrupt handling - the callback for request_irq() */
static irqreturn_t mvneta_isr(int irq, void *dev_id)
{
        struct mvneta_port *pp = (struct mvneta_port *)dev_id;

        /* Mask all interrupts */
        mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0);

        napi_schedule(&pp->napi);

        return IRQ_HANDLED;
}

static int mvneta_fixed_link_update(struct mvneta_port *pp,
                                    struct phy_device *phy)
{
        struct fixed_phy_status status;
        struct fixed_phy_status changed = {};
        u32 gmac_stat = mvreg_read(pp, MVNETA_GMAC_STATUS);

        status.link = !!(gmac_stat & MVNETA_GMAC_LINK_UP);
        if (gmac_stat & MVNETA_GMAC_SPEED_1000)
                status.speed = SPEED_1000;
        else if (gmac_stat & MVNETA_GMAC_SPEED_100)
                status.speed = SPEED_100;
        else
                status.speed = SPEED_10;
        status.duplex = !!(gmac_stat & MVNETA_GMAC_FULL_DUPLEX);
        changed.link = 1;
        changed.speed = 1;
        changed.duplex = 1;
        fixed_phy_update_state(phy, &status, &changed);
        return 0;
}

/* NAPI handler
 * Bits 0 - 7 of the causeRxTx register indicate that are transmitted
 * packets on the corresponding TXQ (Bit 0 is for TX queue 1).
 * Bits 8 -15 of the cause Rx Tx register indicate that are received
 * packets on the corresponding RXQ (Bit 8 is for RX queue 0).
 * Each CPU has its own causeRxTx register
 */
static int mvneta_poll(struct napi_struct *napi, int budget)
{
        int rx_done = 0;
        u32 cause_rx_tx;
        unsigned long flags;
        struct mvneta_port *pp = netdev_priv(napi->dev);

        if (!netif_running(pp->dev)) {
                napi_complete(napi);
                return rx_done;
        }

        /* Read cause register */
        cause_rx_tx = mvreg_read(pp, MVNETA_INTR_NEW_CAUSE);
        if (cause_rx_tx & MVNETA_MISCINTR_INTR_MASK) {
                u32 cause_misc = mvreg_read(pp, MVNETA_INTR_MISC_CAUSE);

                mvreg_write(pp, MVNETA_INTR_MISC_CAUSE, 0);
                if (pp->use_inband_status && (cause_misc &
                                (MVNETA_CAUSE_PHY_STATUS_CHANGE |
                                 MVNETA_CAUSE_LINK_CHANGE |
                                 MVNETA_CAUSE_PSC_SYNC_CHANGE))) {
                        mvneta_fixed_link_update(pp, pp->phy_dev);
                }
        }

        /* Release Tx descriptors */
        if (cause_rx_tx & MVNETA_TX_INTR_MASK_ALL) {
                mvneta_tx_done_gbe(pp, (cause_rx_tx & MVNETA_TX_INTR_MASK_ALL));
                cause_rx_tx &= ~MVNETA_TX_INTR_MASK_ALL;
        }

        /* For the case where the last mvneta_poll did not process all
         * RX packets
         */
        cause_rx_tx |= pp->cause_rx_tx;
        if (rxq_number > 1) {
                while ((cause_rx_tx & MVNETA_RX_INTR_MASK_ALL) && (budget > 0)) {
                        int count;
                        struct mvneta_rx_queue *rxq;
                        /* get rx queue number from cause_rx_tx */
                        rxq = mvneta_rx_policy(pp, cause_rx_tx);
                        if (!rxq)
                                break;

                        /* process the packet in that rx queue */
                        count = mvneta_rx(pp, budget, rxq);
                        rx_done += count;
                        budget -= count;
                        if (budget > 0) {
                                /* set off the rx bit of the
                                 * corresponding bit in the cause rx
                                 * tx register, so that next iteration
                                 * will find the next rx queue where
                                 * packets are received on
                                 */
                                cause_rx_tx &= ~((1 << rxq->id) << 8);
                        }
                }
        } else {
                rx_done = mvneta_rx(pp, budget, &pp->rxqs[rxq_def]);
                budget -= rx_done;
        }

        if (budget > 0) {
                cause_rx_tx = 0;
                napi_complete(napi);
                local_irq_save(flags);
                mvreg_write(pp, MVNETA_INTR_NEW_MASK,
                            MVNETA_RX_INTR_MASK(rxq_number) |
                            MVNETA_TX_INTR_MASK(txq_number) |
                            MVNETA_MISCINTR_INTR_MASK);
                local_irq_restore(flags);
        }

        pp->cause_rx_tx = cause_rx_tx;
        return rx_done;
}

/* Handle rxq fill: allocates rxq skbs; called when initializing a port */
static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
                           int num)
{
        int i;

        for (i = 0; i < num; i++) {
                memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc));
                if (mvneta_rx_refill(pp, rxq->descs + i) != 0) {
                        netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs  filled\n",
                                __func__, rxq->id, i, num);
                        break;
                }
        }

        /* Add this number of RX descriptors as non occupied (ready to
         * get packets)
         */
        mvneta_rxq_non_occup_desc_add(pp, rxq, i);

        return i;
}

/* Free all packets pending transmit from all TXQs and reset TX port */
static void mvneta_tx_reset(struct mvneta_port *pp)
{
        int queue;

        /* free the skb's in the tx ring */
        for (queue = 0; queue < txq_number; queue++)
                mvneta_txq_done_force(pp, &pp->txqs[queue]);

        mvreg_write(pp, MVNETA_PORT_TX_RESET, MVNETA_PORT_TX_DMA_RESET);
        mvreg_write(pp, MVNETA_PORT_TX_RESET, 0);
}

static void mvneta_rx_reset(struct mvneta_port *pp)
{
        mvreg_write(pp, MVNETA_PORT_RX_RESET, MVNETA_PORT_RX_DMA_RESET);
        mvreg_write(pp, MVNETA_PORT_RX_RESET, 0);
}

/* Rx/Tx queue initialization/cleanup methods */

/* Create a specified RX queue */
static int mvneta_rxq_init(struct mvneta_port *pp,
                           struct mvneta_rx_queue *rxq)

{
        rxq->size = pp->rx_ring_size;

        /* Allocate memory for RX descriptors */
        rxq->descs = dma_alloc_coherent(pp->dev->dev.parent,
                                        rxq->size * MVNETA_DESC_ALIGNED_SIZE,
                                        &rxq->descs_phys, GFP_KERNEL);
        if (rxq->descs == NULL)
                return -ENOMEM;

        BUG_ON(rxq->descs !=
               PTR_ALIGN(rxq->descs, MVNETA_CPU_D_CACHE_LINE_SIZE));

        rxq->last_desc = rxq->size - 1;

        /* Set Rx descriptors queue starting address */
        mvreg_write(pp, MVNETA_RXQ_BASE_ADDR_REG(rxq->id), rxq->descs_phys);
        mvreg_write(pp, MVNETA_RXQ_SIZE_REG(rxq->id), rxq->size);

        /* Set Offset */
        mvneta_rxq_offset_set(pp, rxq, NET_SKB_PAD);

        /* Set coalescing pkts and time */
        mvneta_rx_pkts_coal_set(pp, rxq, rxq->pkts_coal);
        mvneta_rx_time_coal_set(pp, rxq, rxq->time_coal);

        /* Fill RXQ with buffers from RX pool */
        mvneta_rxq_buf_size_set(pp, rxq, MVNETA_RX_BUF_SIZE(pp->pkt_size));
        mvneta_rxq_bm_disable(pp, rxq);
        mvneta_rxq_fill(pp, rxq, rxq->size);

        return 0;
}

/* Cleanup Rx queue */
static void mvneta_rxq_deinit(struct mvneta_port *pp,
                              struct mvneta_rx_queue *rxq)
{
        mvneta_rxq_drop_pkts(pp, rxq);

        if (rxq->descs)
                dma_free_coherent(pp->dev->dev.parent,
                                  rxq->size * MVNETA_DESC_ALIGNED_SIZE,
                                  rxq->descs,
                                  rxq->descs_phys);

        rxq->descs             = NULL;
        rxq->last_desc         = 0;
        rxq->next_desc_to_proc = 0;
        rxq->descs_phys        = 0;
}

/* Create and initialize a tx queue */
static int mvneta_txq_init(struct mvneta_port *pp,
                           struct mvneta_tx_queue *txq)
{
        txq->size = pp->tx_ring_size;

        /* A queue must always have room for at least one skb.
         * Therefore, stop the queue when the free entries reaches
         * the maximum number of descriptors per skb.
         */
        txq->tx_stop_threshold = txq->size - MVNETA_MAX_SKB_DESCS;
        txq->tx_wake_threshold = txq->tx_stop_threshold / 2;


        /* Allocate memory for TX descriptors */
        txq->descs = dma_alloc_coherent(pp->dev->dev.parent,
                                        txq->size * MVNETA_DESC_ALIGNED_SIZE,
                                        &txq->descs_phys, GFP_KERNEL);
        if (txq->descs == NULL)
                return -ENOMEM;

        /* Make sure descriptor address is cache line size aligned  */
        BUG_ON(txq->descs !=
               PTR_ALIGN(txq->descs, MVNETA_CPU_D_CACHE_LINE_SIZE));

        txq->last_desc = txq->size - 1;

        /* Set maximum bandwidth for enabled TXQs */
        mvreg_write(pp, MVETH_TXQ_TOKEN_CFG_REG(txq->id), 0x03ffffff);
        mvreg_write(pp, MVETH_TXQ_TOKEN_COUNT_REG(txq->id), 0x3fffffff);

        /* Set Tx descriptors queue starting address */
        mvreg_write(pp, MVNETA_TXQ_BASE_ADDR_REG(txq->id), txq->descs_phys);
        mvreg_write(pp, MVNETA_TXQ_SIZE_REG(txq->id), txq->size);

        txq->tx_skb = kmalloc(txq->size * sizeof(*txq->tx_skb), GFP_KERNEL);
        if (txq->tx_skb == NULL) {
                dma_free_coherent(pp->dev->dev.parent,
                                  txq->size * MVNETA_DESC_ALIGNED_SIZE,
                                  txq->descs, txq->descs_phys);
                return -ENOMEM;
        }

        /* Allocate DMA buffers for TSO MAC/IP/TCP headers */
        txq->tso_hdrs = dma_alloc_coherent(pp->dev->dev.parent,
                                           txq->size * TSO_HEADER_SIZE,
                                           &txq->tso_hdrs_phys, GFP_KERNEL);
        if (txq->tso_hdrs == NULL) {
                kfree(txq->tx_skb);
                dma_free_coherent(pp->dev->dev.parent,
                                  txq->size * MVNETA_DESC_ALIGNED_SIZE,
                                  txq->descs, txq->descs_phys);
                return -ENOMEM;
        }
        mvneta_tx_done_pkts_coal_set(pp, txq, txq->done_pkts_coal);

        return 0;
}

/* Free allocated resources when mvneta_txq_init() fails to allocate memory*/
static void mvneta_txq_deinit(struct mvneta_port *pp,
                              struct mvneta_tx_queue *txq)
{
        kfree(txq->tx_skb);

        if (txq->tso_hdrs)
                dma_free_coherent(pp->dev->dev.parent,
                                  txq->size * TSO_HEADER_SIZE,
                                  txq->tso_hdrs, txq->tso_hdrs_phys);
        if (txq->descs)
                dma_free_coherent(pp->dev->dev.parent,
                                  txq->size * MVNETA_DESC_ALIGNED_SIZE,
                                  txq->descs, txq->descs_phys);

        txq->descs             = NULL;
        txq->last_desc         = 0;
        txq->next_desc_to_proc = 0;
        txq->descs_phys        = 0;

        /* Set minimum bandwidth for disabled TXQs */
        mvreg_write(pp, MVETH_TXQ_TOKEN_CFG_REG(txq->id), 0);
        mvreg_write(pp, MVETH_TXQ_TOKEN_COUNT_REG(txq->id), 0);

        /* Set Tx descriptors queue starting address and size */
        mvreg_write(pp, MVNETA_TXQ_BASE_ADDR_REG(txq->id), 0);
        mvreg_write(pp, MVNETA_TXQ_SIZE_REG(txq->id), 0);
}

/* Cleanup all Tx queues */
static void mvneta_cleanup_txqs(struct mvneta_port *pp)
{
        int queue;

        for (queue = 0; queue < txq_number; queue++)
                mvneta_txq_deinit(pp, &pp->txqs[queue]);
}

/* Cleanup all Rx queues */
static void mvneta_cleanup_rxqs(struct mvneta_port *pp)
{
        int queue;

        for (queue = 0; queue < rxq_number; queue++)
                mvneta_rxq_deinit(pp, &pp->rxqs[queue]);
}


/* Init all Rx queues */
static int mvneta_setup_rxqs(struct mvneta_port *pp)
{
        int queue;

        for (queue = 0; queue < rxq_number; queue++) {
                int err = mvneta_rxq_init(pp, &pp->rxqs[queue]);
                if (err) {
                        netdev_err(pp->dev, "%s: can't create rxq=%d\n",
                                   __func__, queue);
                        mvneta_cleanup_rxqs(pp);
                        return err;
                }
        }

        return 0;
}

/* Init all tx queues */
static int mvneta_setup_txqs(struct mvneta_port *pp)
{
        int queue;

        for (queue = 0; queue < txq_number; queue++) {
                int err = mvneta_txq_init(pp, &pp->txqs[queue]);
                if (err) {
                        netdev_err(pp->dev, "%s: can't create txq=%d\n",
                                   __func__, queue);
                        mvneta_cleanup_txqs(pp);
                        return err;
                }
        }

        return 0;
}

static void mvneta_start_dev(struct mvneta_port *pp)
{
        mvneta_max_rx_size_set(pp, pp->pkt_size);
        mvneta_txq_max_tx_size_set(pp, pp->pkt_size);

        /* start the Rx/Tx activity */
        mvneta_port_enable(pp);

        /* Enable polling on the port */
        napi_enable(&pp->napi);

        /* Unmask interrupts */
        mvreg_write(pp, MVNETA_INTR_NEW_MASK,
                    MVNETA_RX_INTR_MASK(rxq_number) |
                    MVNETA_TX_INTR_MASK(txq_number) |
                    MVNETA_MISCINTR_INTR_MASK);
        mvreg_write(pp, MVNETA_INTR_MISC_MASK,
                    MVNETA_CAUSE_PHY_STATUS_CHANGE |
                    MVNETA_CAUSE_LINK_CHANGE |
                    MVNETA_CAUSE_PSC_SYNC_CHANGE);

        phy_start(pp->phy_dev);
        netif_tx_start_all_queues(pp->dev);
}

static void mvneta_stop_dev(struct mvneta_port *pp)
{
        phy_stop(pp->phy_dev);

        napi_disable(&pp->napi);

        netif_carrier_off(pp->dev);

        mvneta_port_down(pp);
        netif_tx_stop_all_queues(pp->dev);

        /* Stop the port activity */
        mvneta_port_disable(pp);

        /* Clear all ethernet port interrupts */
        mvreg_write(pp, MVNETA_INTR_MISC_CAUSE, 0);
        mvreg_write(pp, MVNETA_INTR_OLD_CAUSE, 0);

        /* Mask all ethernet port interrupts */
        mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0);
        mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0);
        mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0);

        mvneta_tx_reset(pp);
        mvneta_rx_reset(pp);
}

/* Return positive if MTU is valid */
static int mvneta_check_mtu_valid(struct net_device *dev, int mtu)
{
        if (mtu < 68) {
                netdev_err(dev, "cannot change mtu to less than 68\n");
                return -EINVAL;
        }

        /* 9676 == 9700 - 20 and rounding to 8 */
        if (mtu > 9676) {
                netdev_info(dev, "Illegal MTU value %d, round to 9676\n", mtu);
                mtu = 9676;
        }

        if (!IS_ALIGNED(MVNETA_RX_PKT_SIZE(mtu), 8)) {
                netdev_info(dev, "Illegal MTU value %d, rounding to %d\n",
                        mtu, ALIGN(MVNETA_RX_PKT_SIZE(mtu), 8));
                mtu = ALIGN(MVNETA_RX_PKT_SIZE(mtu), 8);
        }

        return mtu;
}

/* Change the device mtu */
static int mvneta_change_mtu(struct net_device *dev, int mtu)
{
        struct mvneta_port *pp = netdev_priv(dev);
        int ret;

        mtu = mvneta_check_mtu_valid(dev, mtu);
        if (mtu < 0)
                return -EINVAL;

        dev->mtu = mtu;

        if (!netif_running(dev)) {
                netdev_update_features(dev);
                return 0;
        }

        /* The interface is running, so we have to force a
         * reallocation of the queues
         */
        mvneta_stop_dev(pp);

        mvneta_cleanup_txqs(pp);
        mvneta_cleanup_rxqs(pp);

        pp->pkt_size = MVNETA_RX_PKT_SIZE(dev->mtu);
        pp->frag_size = SKB_DATA_ALIGN(MVNETA_RX_BUF_SIZE(pp->pkt_size)) +
                        SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

        ret = mvneta_setup_rxqs(pp);
        if (ret) {
                netdev_err(dev, "unable to setup rxqs after MTU change\n");
                return ret;
        }

        ret = mvneta_setup_txqs(pp);
        if (ret) {
                netdev_err(dev, "unable to setup txqs after MTU change\n");
                return ret;
        }

        mvneta_start_dev(pp);
        mvneta_port_up(pp);

        netdev_update_features(dev);

        return 0;
}

static netdev_features_t mvneta_fix_features(struct net_device *dev,
                                             netdev_features_t features)
{
        struct mvneta_port *pp = netdev_priv(dev);

        if (pp->tx_csum_limit && dev->mtu > pp->tx_csum_limit) {
                features &= ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
                netdev_info(dev,
                            "Disable IP checksum for MTU greater than %dB\n",
                            pp->tx_csum_limit);
        }

        return features;
}

/* Get mac address */
static void mvneta_get_mac_addr(struct mvneta_port *pp, unsigned char *addr)
{
        u32 mac_addr_l, mac_addr_h;

        mac_addr_l = mvreg_read(pp, MVNETA_MAC_ADDR_LOW);
        mac_addr_h = mvreg_read(pp, MVNETA_MAC_ADDR_HIGH);
        addr[0] = (mac_addr_h >> 24) & 0xFF;
        addr[1] = (mac_addr_h >> 16) & 0xFF;
        addr[2] = (mac_addr_h >> 8) & 0xFF;
        addr[3] = mac_addr_h & 0xFF;
        addr[4] = (mac_addr_l >> 8) & 0xFF;
        addr[5] = mac_addr_l & 0xFF;
}

/* Handle setting mac address */
static int mvneta_set_mac_addr(struct net_device *dev, void *addr)
{
        struct mvneta_port *pp = netdev_priv(dev);
        struct sockaddr *sockaddr = addr;
        int ret;

        ret = eth_prepare_mac_addr_change(dev, addr);
        if (ret < 0)
                return ret;
        /* Remove previous address table entry */
        mvneta_mac_addr_set(pp, dev->dev_addr, -1);

        /* Set new addr in hw */
        mvneta_mac_addr_set(pp, sockaddr->sa_data, rxq_def);

        eth_commit_mac_addr_change(dev, addr);
        return 0;
}

static void mvneta_adjust_link(struct net_device *ndev)
{
        struct mvneta_port *pp = netdev_priv(ndev);
        struct phy_device *phydev = pp->phy_dev;
        int status_change = 0;

        if (phydev->link) {
                if ((pp->speed != phydev->speed) ||
                    (pp->duplex != phydev->duplex)) {
                        u32 val;

                        val = mvreg_read(pp, MVNETA_GMAC_AUTONEG_CONFIG);
                        val &= ~(MVNETA_GMAC_CONFIG_MII_SPEED |
                                 MVNETA_GMAC_CONFIG_GMII_SPEED |
                                 MVNETA_GMAC_CONFIG_FULL_DUPLEX);

                        if (phydev->duplex)
                                val |= MVNETA_GMAC_CONFIG_FULL_DUPLEX;

                        if (phydev->speed == SPEED_1000)
                                val |= MVNETA_GMAC_CONFIG_GMII_SPEED;
                        else if (phydev->speed == SPEED_100)
                                val |= MVNETA_GMAC_CONFIG_MII_SPEED;

                        mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG, val);

                        pp->duplex = phydev->duplex;
                        pp->speed  = phydev->speed;
                }
        }

        if (phydev->link != pp->link) {
                if (!phydev->link) {
                        pp->duplex = -1;
                        pp->speed = 0;
                }

                pp->link = phydev->link;
                status_change = 1;
        }

        if (status_change) {
                if (phydev->link) {
                        if (!pp->use_inband_status) {
                                u32 val = mvreg_read(pp,
                                                  MVNETA_GMAC_AUTONEG_CONFIG);
                                val &= ~MVNETA_GMAC_FORCE_LINK_DOWN;
                                val |= MVNETA_GMAC_FORCE_LINK_PASS;
                                mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG,
                                            val);
                        }
                        mvneta_port_up(pp);
                } else {
                        if (!pp->use_inband_status) {
                                u32 val = mvreg_read(pp,
                                                  MVNETA_GMAC_AUTONEG_CONFIG);
                                val &= ~MVNETA_GMAC_FORCE_LINK_PASS;
                                val |= MVNETA_GMAC_FORCE_LINK_DOWN;
                                mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG,
                                            val);
                        }
                        mvneta_port_down(pp);
                }
                phy_print_status(phydev);
        }
}

static int mvneta_mdio_probe(struct mvneta_port *pp)
{
        struct phy_device *phy_dev;

        phy_dev = of_phy_connect(pp->dev, pp->phy_node, mvneta_adjust_link, 0,
                                 pp->phy_interface);
        if (!phy_dev) {
                netdev_err(pp->dev, "could not find the PHY\n");
                return -ENODEV;
        }

        phy_dev->supported &= PHY_GBIT_FEATURES;
        phy_dev->advertising = phy_dev->supported;

        pp->phy_dev = phy_dev;
        pp->link    = 0;
        pp->duplex  = 0;
        pp->speed   = 0;

        return 0;
}

static void mvneta_mdio_remove(struct mvneta_port *pp)
{
        phy_disconnect(pp->phy_dev);
        pp->phy_dev = NULL;
}

static int mvneta_open(struct net_device *dev)
{
        struct mvneta_port *pp = netdev_priv(dev);
        int ret;

        pp->pkt_size = MVNETA_RX_PKT_SIZE(pp->dev->mtu);
        pp->frag_size = SKB_DATA_ALIGN(MVNETA_RX_BUF_SIZE(pp->pkt_size)) +
                        SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

        ret = mvneta_setup_rxqs(pp);
        if (ret)
                return ret;

        ret = mvneta_setup_txqs(pp);
        if (ret)
                goto err_cleanup_rxqs;

        /* Connect to port interrupt line */
        ret = request_irq(pp->dev->irq, mvneta_isr, 0,
                          MVNETA_DRIVER_NAME, pp);
        if (ret) {
                netdev_err(pp->dev, "cannot request irq %d\n", pp->dev->irq);
                goto err_cleanup_txqs;
        }

        /* In default link is down */
        netif_carrier_off(pp->dev);

        ret = mvneta_mdio_probe(pp);
        if (ret < 0) {
                netdev_err(dev, "cannot probe MDIO bus\n");
                goto err_free_irq;
        }

        mvneta_start_dev(pp);

        return 0;

err_free_irq:
        free_irq(pp->dev->irq, pp);
err_cleanup_txqs:
        mvneta_cleanup_txqs(pp);
err_cleanup_rxqs:
        mvneta_cleanup_rxqs(pp);
        return ret;
}

/* Stop the port, free port interrupt line */
static int mvneta_stop(struct net_device *dev)
{
        struct mvneta_port *pp = netdev_priv(dev);

        mvneta_stop_dev(pp);
        mvneta_mdio_remove(pp);
        free_irq(dev->irq, pp);
        mvneta_cleanup_rxqs(pp);
        mvneta_cleanup_txqs(pp);

        return 0;
}

static int mvneta_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
        struct mvneta_port *pp = netdev_priv(dev);

        if (!pp->phy_dev)
                return -ENOTSUPP;

        return phy_mii_ioctl(pp->phy_dev, ifr, cmd);
}

/* Ethtool methods */

/* Get settings (phy address, speed) for ethtools */
int mvneta_ethtool_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
        struct mvneta_port *pp = netdev_priv(dev);

        if (!pp->phy_dev)
                return -ENODEV;

        return phy_ethtool_gset(pp->phy_dev, cmd);
}

/* Set settings (phy address, speed) for ethtools */
int mvneta_ethtool_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
        struct mvneta_port *pp = netdev_priv(dev);

        if (!pp->phy_dev)
                return -ENODEV;

        return phy_ethtool_sset(pp->phy_dev, cmd);
}

/* Set interrupt coalescing for ethtools */
static int mvneta_ethtool_set_coalesce(struct net_device *dev,
                                       struct ethtool_coalesce *c)
{
        struct mvneta_port *pp = netdev_priv(dev);
        int queue;

        for (queue = 0; queue < rxq_number; queue++) {
                struct mvneta_rx_queue *rxq = &pp->rxqs[queue];
                rxq->time_coal = c->rx_coalesce_usecs;
                rxq->pkts_coal = c->rx_max_coalesced_frames;
                mvneta_rx_pkts_coal_set(pp, rxq, rxq->pkts_coal);
                mvneta_rx_time_coal_set(pp, rxq, rxq->time_coal);
        }

        for (queue = 0; queue < txq_number; queue++) {
                struct mvneta_tx_queue *txq = &pp->txqs[queue];
                txq->done_pkts_coal = c->tx_max_coalesced_frames;
                mvneta_tx_done_pkts_coal_set(pp, txq, txq->done_pkts_coal);
        }

        return 0;
}

/* get coalescing for ethtools */
static int mvneta_ethtool_get_coalesce(struct net_device *dev,
                                       struct ethtool_coalesce *c)
{
        struct mvneta_port *pp = netdev_priv(dev);

        c->rx_coalesce_usecs        = pp->rxqs[0].time_coal;
        c->rx_max_coalesced_frames  = pp->rxqs[0].pkts_coal;

        c->tx_max_coalesced_frames =  pp->txqs[0].done_pkts_coal;
        return 0;
}


static void mvneta_ethtool_get_drvinfo(struct net_device *dev,
                                    struct ethtool_drvinfo *drvinfo)
{
        strlcpy(drvinfo->driver, MVNETA_DRIVER_NAME,
                sizeof(drvinfo->driver));
        strlcpy(drvinfo->version, MVNETA_DRIVER_VERSION,
                sizeof(drvinfo->version));
        strlcpy(drvinfo->bus_info, dev_name(&dev->dev),
                sizeof(drvinfo->bus_info));
}


static void mvneta_ethtool_get_ringparam(struct net_device *netdev,
                                         struct ethtool_ringparam *ring)
{
        struct mvneta_port *pp = netdev_priv(netdev);

        ring->rx_max_pending = MVNETA_MAX_RXD;
        ring->tx_max_pending = MVNETA_MAX_TXD;
        ring->rx_pending = pp->rx_ring_size;
        ring->tx_pending = pp->tx_ring_size;
}

static int mvneta_ethtool_set_ringparam(struct net_device *dev,
                                        struct ethtool_ringparam *ring)
{
        struct mvneta_port *pp = netdev_priv(dev);

        if ((ring->rx_pending == 0) || (ring->tx_pending == 0))
                return -EINVAL;
        pp->rx_ring_size = ring->rx_pending < MVNETA_MAX_RXD ?
                ring->rx_pending : MVNETA_MAX_RXD;

        pp->tx_ring_size = clamp_t(u16, ring->tx_pending,
                                   MVNETA_MAX_SKB_DESCS * 2, MVNETA_MAX_TXD);
        if (pp->tx_ring_size != ring->tx_pending)
                netdev_warn(dev, "TX queue size set to %u (requested %u)\n",
                            pp->tx_ring_size, ring->tx_pending);

        if (netif_running(dev)) {
                mvneta_stop(dev);
                if (mvneta_open(dev)) {
                        netdev_err(dev,
                                   "error on opening device after ring param change\n");
                        return -ENOMEM;
                }
        }

        return 0;
}

static const struct net_device_ops mvneta_netdev_ops = {
        .ndo_open            = mvneta_open,
        .ndo_stop            = mvneta_stop,
        .ndo_start_xmit      = mvneta_tx,
        .ndo_set_rx_mode     = mvneta_set_rx_mode,
        .ndo_set_mac_address = mvneta_set_mac_addr,
        .ndo_change_mtu      = mvneta_change_mtu,
        .ndo_fix_features    = mvneta_fix_features,
        .ndo_get_stats64     = mvneta_get_stats64,
        .ndo_do_ioctl        = mvneta_ioctl,
};

const struct ethtool_ops mvneta_eth_tool_ops = {
        .get_link       = ethtool_op_get_link,
        .get_settings   = mvneta_ethtool_get_settings,
        .set_settings   = mvneta_ethtool_set_settings,
        .set_coalesce   = mvneta_ethtool_set_coalesce,
        .get_coalesce   = mvneta_ethtool_get_coalesce,
        .get_drvinfo    = mvneta_ethtool_get_drvinfo,
        .get_ringparam  = mvneta_ethtool_get_ringparam,
        .set_ringparam  = mvneta_ethtool_set_ringparam,
};

/* Initialize hw */
static int mvneta_init(struct device *dev, struct mvneta_port *pp)
{
        int queue;

        /* Disable port */
        mvneta_port_disable(pp);

        /* Set port default values */
        mvneta_defaults_set(pp);

        pp->txqs = devm_kcalloc(dev, txq_number, sizeof(struct mvneta_tx_queue),
                                GFP_KERNEL);
        if (!pp->txqs)
                return -ENOMEM;

        /* Initialize TX descriptor rings */
        for (queue = 0; queue < txq_number; queue++) {
                struct mvneta_tx_queue *txq = &pp->txqs[queue];
                txq->id = queue;
                txq->size = pp->tx_ring_size;
                txq->done_pkts_coal = MVNETA_TXDONE_COAL_PKTS;
        }

        pp->rxqs = devm_kcalloc(dev, rxq_number, sizeof(struct mvneta_rx_queue),
                                GFP_KERNEL);
        if (!pp->rxqs)
                return -ENOMEM;

        /* Create Rx descriptor rings */
        for (queue = 0; queue < rxq_number; queue++) {
                struct mvneta_rx_queue *rxq = &pp->rxqs[queue];
                rxq->id = queue;
                rxq->size = pp->rx_ring_size;
                rxq->pkts_coal = MVNETA_RX_COAL_PKTS;
                rxq->time_coal = MVNETA_RX_COAL_USEC;
        }

        return 0;
}

/* platform glue : initialize decoding windows */
static void mvneta_conf_mbus_windows(struct mvneta_port *pp,
                                     const struct mbus_dram_target_info *dram)
{
        u32 win_enable;
        u32 win_protect;
        int i;

        for (i = 0; i < 6; i++) {
                mvreg_write(pp, MVNETA_WIN_BASE(i), 0);
                mvreg_write(pp, MVNETA_WIN_SIZE(i), 0);

                if (i < 4)
                        mvreg_write(pp, MVNETA_WIN_REMAP(i), 0);
        }

        win_enable = 0x3f;
        win_protect = 0;

        for (i = 0; i < dram->num_cs; i++) {
                const struct mbus_dram_window *cs = dram->cs + i;
                mvreg_write(pp, MVNETA_WIN_BASE(i), (cs->base & 0xffff0000) |
                            (cs->mbus_attr << 8) | dram->mbus_dram_target_id);

                mvreg_write(pp, MVNETA_WIN_SIZE(i),
                            (cs->size - 1) & 0xffff0000);

                win_enable &= ~(1 << i);
                win_protect |= 3 << (2 * i);
        }

        mvreg_write(pp, MVNETA_BASE_ADDR_ENABLE, win_enable);
}

/* Power up the port */
static int mvneta_port_power_up(struct mvneta_port *pp, int phy_mode)
{
        u32 ctrl;

        /* MAC Cause register should be cleared */
        mvreg_write(pp, MVNETA_UNIT_INTR_CAUSE, 0);

        ctrl = mvreg_read(pp, MVNETA_GMAC_CTRL_2);

        /* Even though it might look weird, when we're configured in
         * SGMII or QSGMII mode, the RGMII bit needs to be set.
         */
        switch(phy_mode) {
        case PHY_INTERFACE_MODE_QSGMII:
                mvreg_write(pp, MVNETA_SERDES_CFG, MVNETA_QSGMII_SERDES_PROTO);
                ctrl |= MVNETA_GMAC2_PCS_ENABLE | MVNETA_GMAC2_PORT_RGMII;
                break;
        case PHY_INTERFACE_MODE_SGMII:
                mvreg_write(pp, MVNETA_SERDES_CFG, MVNETA_SGMII_SERDES_PROTO);
                ctrl |= MVNETA_GMAC2_PCS_ENABLE | MVNETA_GMAC2_PORT_RGMII;
                break;
        case PHY_INTERFACE_MODE_RGMII:
        case PHY_INTERFACE_MODE_RGMII_ID:
                ctrl |= MVNETA_GMAC2_PORT_RGMII;
                break;
        default:
                return -EINVAL;
        }

        if (pp->use_inband_status)
                ctrl |= MVNETA_GMAC2_INBAND_AN_ENABLE;

        /* Cancel Port Reset */
        ctrl &= ~MVNETA_GMAC2_PORT_RESET;
        mvreg_write(pp, MVNETA_GMAC_CTRL_2, ctrl);

        while ((mvreg_read(pp, MVNETA_GMAC_CTRL_2) &
                MVNETA_GMAC2_PORT_RESET) != 0)
                continue;

        return 0;
}

/* Device initialization routine */
static int mvneta_probe(struct platform_device *pdev)
{
        const struct mbus_dram_target_info *dram_target_info;
        struct resource *res;
        struct device_node *dn = pdev->dev.of_node;
        struct device_node *phy_node;
        struct mvneta_port *pp;
        struct net_device *dev;
        const char *dt_mac_addr;
        char hw_mac_addr[ETH_ALEN];
        const char *mac_from;
        const char *managed;
        int phy_mode;
        int err;

        /* Our multiqueue support is not complete, so for now, only
         * allow the usage of the first RX queue
         */
        if (rxq_def != 0) {
                dev_err(&pdev->dev, "Invalid rxq_def argument: %d\n", rxq_def);
                return -EINVAL;
        }

        dev = alloc_etherdev_mqs(sizeof(struct mvneta_port), txq_number, rxq_number);
        if (!dev)
                return -ENOMEM;

        dev->irq = irq_of_parse_and_map(dn, 0);
        if (dev->irq == 0) {
                err = -EINVAL;
                goto err_free_netdev;
        }

        phy_node = of_parse_phandle(dn, "phy", 0);
        if (!phy_node) {
                if (!of_phy_is_fixed_link(dn)) {
                        dev_err(&pdev->dev, "no PHY specified\n");
                        err = -ENODEV;
                        goto err_free_irq;
                }

                err = of_phy_register_fixed_link(dn);
                if (err < 0) {
                        dev_err(&pdev->dev, "cannot register fixed PHY\n");
                        goto err_free_irq;
                }

                /* In the case of a fixed PHY, the DT node associated
                 * to the PHY is the Ethernet MAC DT node.
                 */
                phy_node = of_node_get(dn);
        }

        phy_mode = of_get_phy_mode(dn);
        if (phy_mode < 0) {
                dev_err(&pdev->dev, "incorrect phy-mode\n");
                err = -EINVAL;
                goto err_put_phy_node;
        }

        dev->tx_queue_len = MVNETA_MAX_TXD;
        dev->watchdog_timeo = 5 * HZ;
        dev->netdev_ops = &mvneta_netdev_ops;

        dev->ethtool_ops = &mvneta_eth_tool_ops;

        pp = netdev_priv(dev);
        pp->phy_node = phy_node;
        pp->phy_interface = phy_mode;

        err = of_property_read_string(dn, "managed", &managed);
        pp->use_inband_status = (err == 0 &&
                                 strcmp(managed, "in-band-status") == 0);

        pp->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(pp->clk)) {
                err = PTR_ERR(pp->clk);
                goto err_put_phy_node;
        }

        clk_prepare_enable(pp->clk);

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        pp->base = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(pp->base)) {
                err = PTR_ERR(pp->base);
                goto err_clk;
        }

        /* Alloc per-cpu stats */
        pp->stats = netdev_alloc_pcpu_stats(struct mvneta_pcpu_stats);
        if (!pp->stats) {
                err = -ENOMEM;
                goto err_clk;
        }

        dt_mac_addr = of_get_mac_address(dn);
        if (dt_mac_addr) {
                mac_from = "device tree";
                memcpy(dev->dev_addr, dt_mac_addr, ETH_ALEN);
        } else {
                mvneta_get_mac_addr(pp, hw_mac_addr);
                if (is_valid_ether_addr(hw_mac_addr)) {
                        mac_from = "hardware";
                        memcpy(dev->dev_addr, hw_mac_addr, ETH_ALEN);
                } else {
                        mac_from = "random";
                        eth_hw_addr_random(dev);
                }
        }

        if (of_device_is_compatible(dn, "marvell,armada-370-neta"))
                pp->tx_csum_limit = 1600;

        pp->tx_ring_size = MVNETA_MAX_TXD;
        pp->rx_ring_size = MVNETA_MAX_RXD;

        pp->dev = dev;
        SET_NETDEV_DEV(dev, &pdev->dev);

        err = mvneta_init(&pdev->dev, pp);
        if (err < 0)
                goto err_free_stats;

        err = mvneta_port_power_up(pp, phy_mode);
        if (err < 0) {
                dev_err(&pdev->dev, "can't power up port\n");
                goto err_free_stats;
        }

        dram_target_info = mv_mbus_dram_info();
        if (dram_target_info)
                mvneta_conf_mbus_windows(pp, dram_target_info);

        netif_napi_add(dev, &pp->napi, mvneta_poll, NAPI_POLL_WEIGHT);

        dev->features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO;
        dev->hw_features |= dev->features;
        dev->vlan_features |= dev->features;
        dev->priv_flags |= IFF_UNICAST_FLT;
        dev->gso_max_segs = MVNETA_MAX_TSO_SEGS;

        err = register_netdev(dev);
        if (err < 0) {
                dev_err(&pdev->dev, "failed to register\n");
                goto err_free_stats;
        }

        netdev_info(dev, "Using %s mac address %pM\n", mac_from,
                    dev->dev_addr);

        platform_set_drvdata(pdev, pp->dev);

        if (pp->use_inband_status) {
                struct phy_device *phy = of_phy_find_device(dn);

                mvneta_fixed_link_update(pp, phy);
        }

        return 0;

err_free_stats:
        free_percpu(pp->stats);
err_clk:
        clk_disable_unprepare(pp->clk);
err_put_phy_node:
        of_node_put(phy_node);
err_free_irq:
        irq_dispose_mapping(dev->irq);
err_free_netdev:
        free_netdev(dev);
        return err;
}

/* Device removal routine */
static int mvneta_remove(struct platform_device *pdev)
{
        struct net_device  *dev = platform_get_drvdata(pdev);
        struct mvneta_port *pp = netdev_priv(dev);

        unregister_netdev(dev);
        clk_disable_unprepare(pp->clk);
        free_percpu(pp->stats);
        irq_dispose_mapping(dev->irq);
        of_node_put(pp->phy_node);
        free_netdev(dev);

        return 0;
}

static const struct of_device_id mvneta_match[] = {
        { .compatible = "marvell,armada-370-neta" },
        { .compatible = "marvell,armada-xp-neta" },
        { }
};
MODULE_DEVICE_TABLE(of, mvneta_match);

static struct platform_driver mvneta_driver = {
        .probe = mvneta_probe,
        .remove = mvneta_remove,
        .driver = {
                .name = MVNETA_DRIVER_NAME,
                .of_match_table = mvneta_match,
        },
};

module_platform_driver(mvneta_driver);

MODULE_DESCRIPTION("Marvell NETA Ethernet Driver - www.marvell.com");
MODULE_AUTHOR("Rami Rosen <rosenr@marvell.com>, Thomas Petazzoni <thomas.petazzoni@free-electrons.com>");
MODULE_LICENSE("GPL");

module_param(rxq_number, int, S_IRUGO);
module_param(txq_number, int, S_IRUGO);

module_param(rxq_def, int, S_IRUGO);
module_param(rx_copybreak, int, S_IRUGO | S_IWUSR);