/* Agere Systems Inc.
 * 10/100/1000 Base-T Ethernet Driver for the ET1301 and ET131x series MACs
 *
 * Copyright © 2005 Agere Systems Inc.
 * All rights reserved.
 *   http://www.agere.com
 *
 * Copyright (c) 2011 Mark Einon <mark.einon@gmail.com>
 *
 *------------------------------------------------------------------------------
 *
 * SOFTWARE LICENSE
 *
 * This software is provided subject to the following terms and conditions,
 * which you should read carefully before using the software.  Using this
 * software indicates your acceptance of these terms and conditions.  If you do
 * not agree with these terms and conditions, do not use the software.
 *
 * Copyright © 2005 Agere Systems Inc.
 * All rights reserved.
 *
 * Redistribution and use in source or binary forms, with or without
 * modifications, are permitted provided that the following conditions are met:
 *
 * . Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following Disclaimer as comments in the code as
 *    well as in the documentation and/or other materials provided with the
 *    distribution.
 *
 * . Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following Disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * . Neither the name of Agere Systems Inc. nor the names of the contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * Disclaimer
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, INFRINGEMENT AND THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  ANY
 * USE, MODIFICATION OR DISTRIBUTION OF THIS SOFTWARE IS SOLELY AT THE USERS OWN
 * RISK. IN NO EVENT SHALL AGERE SYSTEMS INC. OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, INCLUDING, BUT NOT LIMITED TO, CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/pci.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>

#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/in.h>
#include <linux/delay.h>
#include <linux/bitops.h>
#include <linux/io.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/ioport.h>
#include <linux/crc32.h>
#include <linux/random.h>
#include <linux/phy.h>

#include "et131x.h"

MODULE_AUTHOR("Victor Soriano <vjsoriano@agere.com>");
MODULE_AUTHOR("Mark Einon <mark.einon@gmail.com>");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("10/100/1000 Base-T Ethernet Driver for the ET1310 by Agere Systems");

/* EEPROM defines */
#define MAX_NUM_REGISTER_POLLS          1000
#define MAX_NUM_WRITE_RETRIES           2

/* MAC defines */
#define COUNTER_WRAP_16_BIT 0x10000
#define COUNTER_WRAP_12_BIT 0x1000

/* PCI defines */
#define INTERNAL_MEM_SIZE       0x400   /* 1024 of internal memory */
#define INTERNAL_MEM_RX_OFFSET  0x1FF   /* 50%   Tx, 50%   Rx */

/* ISR defines */
/* For interrupts, normal running is:
 *       rxdma_xfr_done, phy_interrupt, mac_stat_interrupt,
 *       watchdog_interrupt & txdma_xfer_done
 *
 * In both cases, when flow control is enabled for either Tx or bi-direction,
 * we additional enable rx_fbr0_low and rx_fbr1_low, so we know when the
 * buffer rings are running low.
 */
#define INT_MASK_DISABLE            0xffffffff

/* NOTE: Masking out MAC_STAT Interrupt for now...
 * #define INT_MASK_ENABLE             0xfff6bf17
 * #define INT_MASK_ENABLE_NO_FLOW     0xfff6bfd7
 */
#define INT_MASK_ENABLE             0xfffebf17
#define INT_MASK_ENABLE_NO_FLOW     0xfffebfd7

/* General defines */
/* Packet and header sizes */
#define NIC_MIN_PACKET_SIZE     60

/* Multicast list size */
#define NIC_MAX_MCAST_LIST      128

/* Supported Filters */
#define ET131X_PACKET_TYPE_DIRECTED             0x0001
#define ET131X_PACKET_TYPE_MULTICAST            0x0002
#define ET131X_PACKET_TYPE_BROADCAST            0x0004
#define ET131X_PACKET_TYPE_PROMISCUOUS          0x0008
#define ET131X_PACKET_TYPE_ALL_MULTICAST        0x0010

/* Tx Timeout */
#define ET131X_TX_TIMEOUT       (1 * HZ)
#define NIC_SEND_HANG_THRESHOLD 0

/* MP_TCB flags */
#define FMP_DEST_MULTI                  0x00000001
#define FMP_DEST_BROAD                  0x00000002

/* MP_ADAPTER flags */
#define FMP_ADAPTER_INTERRUPT_IN_USE    0x00000008

/* MP_SHARED flags */
#define FMP_ADAPTER_LOWER_POWER         0x00200000

#define FMP_ADAPTER_NON_RECOVER_ERROR   0x00800000
#define FMP_ADAPTER_HARDWARE_ERROR      0x04000000

#define FMP_ADAPTER_FAIL_SEND_MASK      0x3ff00000

/* Some offsets in PCI config space that are actually used. */
#define ET1310_PCI_MAC_ADDRESS          0xA4
#define ET1310_PCI_EEPROM_STATUS        0xB2
#define ET1310_PCI_ACK_NACK             0xC0
#define ET1310_PCI_REPLAY               0xC2
#define ET1310_PCI_L0L1LATENCY          0xCF

/* PCI Product IDs */
#define ET131X_PCI_DEVICE_ID_GIG        0xED00  /* ET1310 1000 Base-T 8 */
#define ET131X_PCI_DEVICE_ID_FAST       0xED01  /* ET1310 100  Base-T */

/* Define order of magnitude converter */
#define NANO_IN_A_MICRO 1000

#define PARM_RX_NUM_BUFS_DEF    4
#define PARM_RX_TIME_INT_DEF    10
#define PARM_RX_MEM_END_DEF     0x2bc
#define PARM_TX_TIME_INT_DEF    40
#define PARM_TX_NUM_BUFS_DEF    4
#define PARM_DMA_CACHE_DEF      0

/* RX defines */
#define FBR_CHUNKS              32
#define MAX_DESC_PER_RING_RX    1024

/* number of RFDs - default and min */
#define RFD_LOW_WATER_MARK      40
#define NIC_DEFAULT_NUM_RFD     1024
#define NUM_FBRS                2

#define NUM_PACKETS_HANDLED     256

#define ALCATEL_MULTICAST_PKT   0x01000000
#define ALCATEL_BROADCAST_PKT   0x02000000

/* typedefs for Free Buffer Descriptors */
struct fbr_desc {
        u32 addr_lo;
        u32 addr_hi;
        u32 word2;              /* Bits 10-31 reserved, 0-9 descriptor */
};

/* Packet Status Ring Descriptors
 *
 * Word 0:
 *
 * top 16 bits are from the Alcatel Status Word as enumerated in
 * PE-MCXMAC Data Sheet IPD DS54 0210-1 (also IPD-DS80 0205-2)
 *
 * 0: hp                        hash pass
 * 1: ipa                       IP checksum assist
 * 2: ipp                       IP checksum pass
 * 3: tcpa                      TCP checksum assist
 * 4: tcpp                      TCP checksum pass
 * 5: wol                       WOL Event
 * 6: rxmac_error               RXMAC Error Indicator
 * 7: drop                      Drop packet
 * 8: ft                        Frame Truncated
 * 9: jp                        Jumbo Packet
 * 10: vp                       VLAN Packet
 * 11-15: unused
 * 16: asw_prev_pkt_dropped     e.g. IFG too small on previous
 * 17: asw_RX_DV_event          short receive event detected
 * 18: asw_false_carrier_event  bad carrier since last good packet
 * 19: asw_code_err             one or more nibbles signalled as errors
 * 20: asw_CRC_err              CRC error
 * 21: asw_len_chk_err          frame length field incorrect
 * 22: asw_too_long             frame length > 1518 bytes
 * 23: asw_OK                   valid CRC + no code error
 * 24: asw_multicast            has a multicast address
 * 25: asw_broadcast            has a broadcast address
 * 26: asw_dribble_nibble       spurious bits after EOP
 * 27: asw_control_frame        is a control frame
 * 28: asw_pause_frame          is a pause frame
 * 29: asw_unsupported_op       unsupported OP code
 * 30: asw_VLAN_tag             VLAN tag detected
 * 31: asw_long_evt             Rx long event
 *
 * Word 1:
 * 0-15: length                 length in bytes
 * 16-25: bi                    Buffer Index
 * 26-27: ri                    Ring Index
 * 28-31: reserved
 */

struct pkt_stat_desc {
        u32 word0;
        u32 word1;
};

/* Typedefs for the RX DMA status word */

/* rx status word 0 holds part of the status bits of the Rx DMA engine
 * that get copied out to memory by the ET-1310.  Word 0 is a 32 bit word
 * which contains the Free Buffer ring 0 and 1 available offset.
 *
 * bit 0-9 FBR1 offset
 * bit 10 Wrap flag for FBR1
 * bit 16-25 FBR0 offset
 * bit 26 Wrap flag for FBR0
 */

/* RXSTAT_WORD1_t structure holds part of the status bits of the Rx DMA engine
 * that get copied out to memory by the ET-1310.  Word 3 is a 32 bit word
 * which contains the Packet Status Ring available offset.
 *
 * bit 0-15 reserved
 * bit 16-27 PSRoffset
 * bit 28 PSRwrap
 * bit 29-31 unused
 */

/* struct rx_status_block is a structure representing the status of the Rx
 * DMA engine it sits in free memory, and is pointed to by 0x101c / 0x1020
 */
struct rx_status_block {
        u32 word0;
        u32 word1;
};

/* Structure for look-up table holding free buffer ring pointers, addresses
 * and state.
 */
struct fbr_lookup {
        void            *virt[MAX_DESC_PER_RING_RX];
        u32              bus_high[MAX_DESC_PER_RING_RX];
        u32              bus_low[MAX_DESC_PER_RING_RX];
        void            *ring_virtaddr;
        dma_addr_t       ring_physaddr;
        void            *mem_virtaddrs[MAX_DESC_PER_RING_RX / FBR_CHUNKS];
        dma_addr_t       mem_physaddrs[MAX_DESC_PER_RING_RX / FBR_CHUNKS];
        u32              local_full;
        u32              num_entries;
        dma_addr_t       buffsize;
};

/* struct rx_ring is the sructure representing the adaptor's local
 * reference(s) to the rings
 */
struct rx_ring {
        struct fbr_lookup *fbr[NUM_FBRS];
        void *ps_ring_virtaddr;
        dma_addr_t ps_ring_physaddr;
        u32 local_psr_full;
        u32 psr_num_entries;

        struct rx_status_block *rx_status_block;
        dma_addr_t rx_status_bus;

        /* RECV */
        struct list_head recv_list;
        u32 num_ready_recv;

        u32 num_rfd;

        bool unfinished_receives;
};

/* TX defines */
/* word 2 of the control bits in the Tx Descriptor ring for the ET-1310
 *
 * 0-15: length of packet
 * 16-27: VLAN tag
 * 28: VLAN CFI
 * 29-31: VLAN priority
 *
 * word 3 of the control bits in the Tx Descriptor ring for the ET-1310
 *
 * 0: last packet in the sequence
 * 1: first packet in the sequence
 * 2: interrupt the processor when this pkt sent
 * 3: Control word - no packet data
 * 4: Issue half-duplex backpressure : XON/XOFF
 * 5: send pause frame
 * 6: Tx frame has error
 * 7: append CRC
 * 8: MAC override
 * 9: pad packet
 * 10: Packet is a Huge packet
 * 11: append VLAN tag
 * 12: IP checksum assist
 * 13: TCP checksum assist
 * 14: UDP checksum assist
 */

#define TXDESC_FLAG_LASTPKT             0x0001
#define TXDESC_FLAG_FIRSTPKT            0x0002
#define TXDESC_FLAG_INTPROC             0x0004

/* struct tx_desc represents each descriptor on the ring */
struct tx_desc {
        u32 addr_hi;
        u32 addr_lo;
        u32 len_vlan;   /* control words how to xmit the */
        u32 flags;      /* data (detailed above) */
};

/* The status of the Tx DMA engine it sits in free memory, and is pointed to
 * by 0x101c / 0x1020. This is a DMA10 type
 */

/* TCB (Transmit Control Block: Host Side) */
struct tcb {
        struct tcb *next;       /* Next entry in ring */
        u32 flags;              /* Our flags for the packet */
        u32 count;              /* Used to spot stuck/lost packets */
        u32 stale;              /* Used to spot stuck/lost packets */
        struct sk_buff *skb;    /* Network skb we are tied to */
        u32 index;              /* Ring indexes */
        u32 index_start;
};

/* Structure representing our local reference(s) to the ring */
struct tx_ring {
        /* TCB (Transmit Control Block) memory and lists */
        struct tcb *tcb_ring;

        /* List of TCBs that are ready to be used */
        struct tcb *tcb_qhead;
        struct tcb *tcb_qtail;

        /* list of TCBs that are currently being sent.  NOTE that access to all
         * three of these (including used) are controlled via the
         * TCBSendQLock.  This lock should be secured prior to incementing /
         * decrementing used, or any queue manipulation on send_head /
         * tail
         */
        struct tcb *send_head;
        struct tcb *send_tail;
        int used;

        /* The actual descriptor ring */
        struct tx_desc *tx_desc_ring;
        dma_addr_t tx_desc_ring_pa;

        /* send_idx indicates where we last wrote to in the descriptor ring. */
        u32 send_idx;

        /* The location of the write-back status block */
        u32 *tx_status;
        dma_addr_t tx_status_pa;

        /* Packets since the last IRQ: used for interrupt coalescing */
        int since_irq;
};

/* Do not change these values: if changed, then change also in respective
 * TXdma and Rxdma engines
 */
#define NUM_DESC_PER_RING_TX         512    /* TX Do not change these values */
#define NUM_TCB                      64

/* These values are all superseded by registry entries to facilitate tuning.
 * Once the desired performance has been achieved, the optimal registry values
 * should be re-populated to these #defines:
 */
#define TX_ERROR_PERIOD             1000

#define LO_MARK_PERCENT_FOR_PSR     15
#define LO_MARK_PERCENT_FOR_RX      15

/* RFD (Receive Frame Descriptor) */
struct rfd {
        struct list_head list_node;
        struct sk_buff *skb;
        u32 len;        /* total size of receive frame */
        u16 bufferindex;
        u8 ringindex;
};

/* Flow Control */
#define FLOW_BOTH       0
#define FLOW_TXONLY     1
#define FLOW_RXONLY     2
#define FLOW_NONE       3

/* Struct to define some device statistics */
struct ce_stats {
        /* MIB II variables
         *
         * NOTE: atomic_t types are only guaranteed to store 24-bits; if we
         * MUST have 32, then we'll need another way to perform atomic
         * operations
         */
        u32             unicast_pkts_rcvd;
        atomic_t        unicast_pkts_xmtd;
        u32             multicast_pkts_rcvd;
        atomic_t        multicast_pkts_xmtd;
        u32             broadcast_pkts_rcvd;
        atomic_t        broadcast_pkts_xmtd;
        u32             rcvd_pkts_dropped;

        /* Tx Statistics. */
        u32             tx_underflows;

        u32             tx_collisions;
        u32             tx_excessive_collisions;
        u32             tx_first_collisions;
        u32             tx_late_collisions;
        u32             tx_max_pkt_errs;
        u32             tx_deferred;

        /* Rx Statistics. */
        u32             rx_overflows;

        u32             rx_length_errs;
        u32             rx_align_errs;
        u32             rx_crc_errs;
        u32             rx_code_violations;
        u32             rx_other_errs;

        u32             synchronous_iterations;
        u32             interrupt_status;
};

/* The private adapter structure */
struct et131x_adapter {
        struct net_device *netdev;
        struct pci_dev *pdev;
        struct mii_bus *mii_bus;
        struct phy_device *phydev;
        struct work_struct task;

        /* Flags that indicate current state of the adapter */
        u32 flags;

        /* local link state, to determine if a state change has occurred */
        int link;

        /* Configuration  */
        u8 rom_addr[ETH_ALEN];
        u8 addr[ETH_ALEN];
        bool has_eeprom;
        u8 eeprom_data[2];

        /* Spinlocks */
        spinlock_t tcb_send_qlock;
        spinlock_t tcb_ready_qlock;
        spinlock_t send_hw_lock;

        spinlock_t rcv_lock;
        spinlock_t fbr_lock;

        /* Packet Filter and look ahead size */
        u32 packet_filter;

        /* multicast list */
        u32 multicast_addr_count;
        u8 multicast_list[NIC_MAX_MCAST_LIST][ETH_ALEN];

        /* Pointer to the device's PCI register space */
        struct address_map __iomem *regs;

        /* Registry parameters */
        u8 wanted_flow;         /* Flow we want for 802.3x flow control */
        u32 registry_jumbo_packet;      /* Max supported ethernet packet size */

        /* Derived from the registry: */
        u8 flowcontrol;         /* flow control validated by the far-end */

        /* Minimize init-time */
        struct timer_list error_timer;

        /* variable putting the phy into coma mode when boot up with no cable
         * plugged in after 5 seconds
         */
        u8 boot_coma;

        /* Next two used to save power information at power down. This
         * information will be used during power up to set up parts of Power
         * Management in JAGCore
         */
        u16 pdown_speed;
        u8 pdown_duplex;

        /* Tx Memory Variables */
        struct tx_ring tx_ring;

        /* Rx Memory Variables */
        struct rx_ring rx_ring;

        /* Stats */
        struct ce_stats stats;

        struct net_device_stats net_stats;
};

static int eeprom_wait_ready(struct pci_dev *pdev, u32 *status)
{
        u32 reg;
        int i;

        /* 1. Check LBCIF Status Register for bits 6 & 3:2 all equal to 0 and
         *    bits 7,1:0 both equal to 1, at least once after reset.
         *    Subsequent operations need only to check that bits 1:0 are equal
         *    to 1 prior to starting a single byte read/write
         */

        for (i = 0; i < MAX_NUM_REGISTER_POLLS; i++) {
                /* Read registers grouped in DWORD1 */
                if (pci_read_config_dword(pdev, LBCIF_DWORD1_GROUP, &reg))
                        return -EIO;

                /* I2C idle and Phy Queue Avail both true */
                if ((reg & 0x3000) == 0x3000) {
                        if (status)
                                *status = reg;
                        return reg & 0xFF;
                }
        }
        return -ETIMEDOUT;
}

/* eeprom_write - Write a byte to the ET1310's EEPROM
 * @adapter: pointer to our private adapter structure
 * @addr: the address to write
 * @data: the value to write
 *
 * Returns 1 for a successful write.
 */
static int eeprom_write(struct et131x_adapter *adapter, u32 addr, u8 data)
{
        struct pci_dev *pdev = adapter->pdev;
        int index = 0;
        int retries;
        int err = 0;
        int i2c_wack = 0;
        int writeok = 0;
        u32 status;
        u32 val = 0;

        /* For an EEPROM, an I2C single byte write is defined as a START
         * condition followed by the device address, EEPROM address, one byte
         * of data and a STOP condition.  The STOP condition will trigger the
         * EEPROM's internally timed write cycle to the nonvolatile memory.
         * All inputs are disabled during this write cycle and the EEPROM will
         * not respond to any access until the internal write is complete.
         */

        err = eeprom_wait_ready(pdev, NULL);
        if (err < 0)
                return err;

         /* 2. Write to the LBCIF Control Register:  bit 7=1, bit 6=1, bit 3=0,
          *    and bits 1:0 both =0.  Bit 5 should be set according to the
          *    type of EEPROM being accessed (1=two byte addressing, 0=one
          *    byte addressing).
          */
        if (pci_write_config_byte(pdev, LBCIF_CONTROL_REGISTER,
                        LBCIF_CONTROL_LBCIF_ENABLE | LBCIF_CONTROL_I2C_WRITE))
                return -EIO;

        i2c_wack = 1;

        /* Prepare EEPROM address for Step 3 */

        for (retries = 0; retries < MAX_NUM_WRITE_RETRIES; retries++) {
                /* Write the address to the LBCIF Address Register */
                if (pci_write_config_dword(pdev, LBCIF_ADDRESS_REGISTER, addr))
                        break;
                /* Write the data to the LBCIF Data Register (the I2C write
                 * will begin).
                 */
                if (pci_write_config_byte(pdev, LBCIF_DATA_REGISTER, data))
                        break;
                /* Monitor bit 1:0 of the LBCIF Status Register.  When bits
                 * 1:0 are both equal to 1, the I2C write has completed and the
                 * internal write cycle of the EEPROM is about to start.
                 * (bits 1:0 = 01 is a legal state while waiting from both
                 * equal to 1, but bits 1:0 = 10 is invalid and implies that
                 * something is broken).
                 */
                err = eeprom_wait_ready(pdev, &status);
                if (err < 0)
                        return 0;

                /* Check bit 3 of the LBCIF Status Register.  If  equal to 1,
                 * an error has occurred.Don't break here if we are revision
                 * 1, this is so we do a blind write for load bug.
                 */
                if ((status & LBCIF_STATUS_GENERAL_ERROR)
                        && adapter->pdev->revision == 0)
                        break;

                /* Check bit 2 of the LBCIF Status Register.  If equal to 1 an
                 * ACK error has occurred on the address phase of the write.
                 * This could be due to an actual hardware failure or the
                 * EEPROM may still be in its internal write cycle from a
                 * previous write. This write operation was ignored and must be
                  *repeated later.
                 */
                if (status & LBCIF_STATUS_ACK_ERROR) {
                        /* This could be due to an actual hardware failure
                         * or the EEPROM may still be in its internal write
                         * cycle from a previous write. This write operation
                         * was ignored and must be repeated later.
                         */
                        udelay(10);
                        continue;
                }

                writeok = 1;
                break;
        }

        /* Set bit 6 of the LBCIF Control Register = 0.
         */
        udelay(10);

        while (i2c_wack) {
                if (pci_write_config_byte(pdev, LBCIF_CONTROL_REGISTER,
                        LBCIF_CONTROL_LBCIF_ENABLE))
                        writeok = 0;

                /* Do read until internal ACK_ERROR goes away meaning write
                 * completed
                 */
                do {
                        pci_write_config_dword(pdev,
                                               LBCIF_ADDRESS_REGISTER,
                                               addr);
                        do {
                                pci_read_config_dword(pdev,
                                        LBCIF_DATA_REGISTER, &val);
                        } while ((val & 0x00010000) == 0);
                } while (val & 0x00040000);

                if ((val & 0xFF00) != 0xC000 || index == 10000)
                        break;
                index++;
        }
        return writeok ? 0 : -EIO;
}

/* eeprom_read - Read a byte from the ET1310's EEPROM
 * @adapter: pointer to our private adapter structure
 * @addr: the address from which to read
 * @pdata: a pointer to a byte in which to store the value of the read
 * @eeprom_id: the ID of the EEPROM
 * @addrmode: how the EEPROM is to be accessed
 *
 * Returns 1 for a successful read
 */
static int eeprom_read(struct et131x_adapter *adapter, u32 addr, u8 *pdata)
{
        struct pci_dev *pdev = adapter->pdev;
        int err;
        u32 status;

        /* A single byte read is similar to the single byte write, with the
         * exception of the data flow:
         */

        err = eeprom_wait_ready(pdev, NULL);
        if (err < 0)
                return err;
        /* Write to the LBCIF Control Register:  bit 7=1, bit 6=0, bit 3=0,
         * and bits 1:0 both =0.  Bit 5 should be set according to the type
         * of EEPROM being accessed (1=two byte addressing, 0=one byte
         * addressing).
         */
        if (pci_write_config_byte(pdev, LBCIF_CONTROL_REGISTER,
                                  LBCIF_CONTROL_LBCIF_ENABLE))
                return -EIO;
        /* Write the address to the LBCIF Address Register (I2C read will
         * begin).
         */
        if (pci_write_config_dword(pdev, LBCIF_ADDRESS_REGISTER, addr))
                return -EIO;
        /* Monitor bit 0 of the LBCIF Status Register.  When = 1, I2C read
         * is complete. (if bit 1 =1 and bit 0 stays = 0, a hardware failure
         * has occurred).
         */
        err = eeprom_wait_ready(pdev, &status);
        if (err < 0)
                return err;
        /* Regardless of error status, read data byte from LBCIF Data
         * Register.
         */
        *pdata = err;
        /* Check bit 2 of the LBCIF Status Register.  If = 1,
         * then an error has occurred.
         */
        return (status & LBCIF_STATUS_ACK_ERROR) ? -EIO : 0;
}

static int et131x_init_eeprom(struct et131x_adapter *adapter)
{
        struct pci_dev *pdev = adapter->pdev;
        u8 eestatus;

        /* We first need to check the EEPROM Status code located at offset
         * 0xB2 of config space
         */
        pci_read_config_byte(pdev, ET1310_PCI_EEPROM_STATUS, &eestatus);

        /* THIS IS A WORKAROUND:
         * I need to call this function twice to get my card in a
         * LG M1 Express Dual running. I tried also a msleep before this
         * function, because I thought there could be some time conditions
         * but it didn't work. Call the whole function twice also work.
         */
        if (pci_read_config_byte(pdev, ET1310_PCI_EEPROM_STATUS, &eestatus)) {
                dev_err(&pdev->dev,
                       "Could not read PCI config space for EEPROM Status\n");
                return -EIO;
        }

        /* Determine if the error(s) we care about are present. If they are
         * present we need to fail.
         */
        if (eestatus & 0x4C) {
                int write_failed = 0;

                if (pdev->revision == 0x01) {
                        int     i;
                        static const u8 eedata[4] = { 0xFE, 0x13, 0x10, 0xFF };

                        /* Re-write the first 4 bytes if we have an eeprom
                         * present and the revision id is 1, this fixes the
                         * corruption seen with 1310 B Silicon
                         */
                        for (i = 0; i < 3; i++)
                                if (eeprom_write(adapter, i, eedata[i]) < 0)
                                        write_failed = 1;
                }
                if (pdev->revision  != 0x01 || write_failed) {
                        dev_err(&pdev->dev,
                            "Fatal EEPROM Status Error - 0x%04x\n", eestatus);

                        /* This error could mean that there was an error
                         * reading the eeprom or that the eeprom doesn't exist.
                         * We will treat each case the same and not try to
                         * gather additional information that normally would
                         * come from the eeprom, like MAC Address
                         */
                        adapter->has_eeprom = 0;
                        return -EIO;
                }
        }
        adapter->has_eeprom = 1;

        /* Read the EEPROM for information regarding LED behavior. Refer to
         * ET1310_phy.c, et131x_xcvr_init(), for its use.
         */
        eeprom_read(adapter, 0x70, &adapter->eeprom_data[0]);
        eeprom_read(adapter, 0x71, &adapter->eeprom_data[1]);

        if (adapter->eeprom_data[0] != 0xcd)
                /* Disable all optional features */
                adapter->eeprom_data[1] = 0x00;

        return 0;
}

/* et131x_rx_dma_enable - re-start of Rx_DMA on the ET1310.
 * @adapter: pointer to our adapter structure
 */
static void et131x_rx_dma_enable(struct et131x_adapter *adapter)
{
        /* Setup the receive dma configuration register for normal operation */
        u32 csr =  ET_RXDMA_CSR_FBR1_ENABLE;
        struct rx_ring *rx_ring = &adapter->rx_ring;

        if (rx_ring->fbr[1]->buffsize == 4096)
                csr |= ET_RXDMA_CSR_FBR1_SIZE_LO;
        else if (rx_ring->fbr[1]->buffsize == 8192)
                csr |= ET_RXDMA_CSR_FBR1_SIZE_HI;
        else if (rx_ring->fbr[1]->buffsize == 16384)
                csr |= ET_RXDMA_CSR_FBR1_SIZE_LO | ET_RXDMA_CSR_FBR1_SIZE_HI;

        csr |= ET_RXDMA_CSR_FBR0_ENABLE;
        if (rx_ring->fbr[0]->buffsize == 256)
                csr |= ET_RXDMA_CSR_FBR0_SIZE_LO;
        else if (rx_ring->fbr[0]->buffsize == 512)
                csr |= ET_RXDMA_CSR_FBR0_SIZE_HI;
        else if (rx_ring->fbr[0]->buffsize == 1024)
                csr |= ET_RXDMA_CSR_FBR0_SIZE_LO | ET_RXDMA_CSR_FBR0_SIZE_HI;
        writel(csr, &adapter->regs->rxdma.csr);

        csr = readl(&adapter->regs->rxdma.csr);
        if (csr & ET_RXDMA_CSR_HALT_STATUS) {
                udelay(5);
                csr = readl(&adapter->regs->rxdma.csr);
                if (csr & ET_RXDMA_CSR_HALT_STATUS) {
                        dev_err(&adapter->pdev->dev,
                            "RX Dma failed to exit halt state.  CSR 0x%08x\n",
                                csr);
                }
        }
}

/* et131x_rx_dma_disable - Stop of Rx_DMA on the ET1310
 * @adapter: pointer to our adapter structure
 */
static void et131x_rx_dma_disable(struct et131x_adapter *adapter)
{
        u32 csr;
        /* Setup the receive dma configuration register */
        writel(ET_RXDMA_CSR_HALT | ET_RXDMA_CSR_FBR1_ENABLE,
               &adapter->regs->rxdma.csr);
        csr = readl(&adapter->regs->rxdma.csr);
        if (!(csr & ET_RXDMA_CSR_HALT_STATUS)) {
                udelay(5);
                csr = readl(&adapter->regs->rxdma.csr);
                if (!(csr & ET_RXDMA_CSR_HALT_STATUS))
                        dev_err(&adapter->pdev->dev,
                              "RX Dma failed to enter halt state. CSR 0x%08x\n",
                              csr);
        }
}

/* et131x_tx_dma_enable - re-start of Tx_DMA on the ET1310.
 * @adapter: pointer to our adapter structure
 *
 * Mainly used after a return to the D0 (full-power) state from a lower state.
 */
static void et131x_tx_dma_enable(struct et131x_adapter *adapter)
{
        /* Setup the transmit dma configuration register for normal
         * operation
         */
        writel(ET_TXDMA_SNGL_EPKT|(PARM_DMA_CACHE_DEF << ET_TXDMA_CACHE_SHIFT),
                                        &adapter->regs->txdma.csr);
}

static inline void add_10bit(u32 *v, int n)
{
        *v = INDEX10(*v + n) | (*v & ET_DMA10_WRAP);
}

static inline void add_12bit(u32 *v, int n)
{
        *v = INDEX12(*v + n) | (*v & ET_DMA12_WRAP);
}

/* et1310_config_mac_regs1 - Initialize the first part of MAC regs
 * @adapter: pointer to our adapter structure
 */
static void et1310_config_mac_regs1(struct et131x_adapter *adapter)
{
        struct mac_regs __iomem *macregs = &adapter->regs->mac;
        u32 station1;
        u32 station2;
        u32 ipg;

        /* First we need to reset everything.  Write to MAC configuration
         * register 1 to perform reset.
         */
        writel(ET_MAC_CFG1_SOFT_RESET | ET_MAC_CFG1_SIM_RESET  |
               ET_MAC_CFG1_RESET_RXMC | ET_MAC_CFG1_RESET_TXMC |
               ET_MAC_CFG1_RESET_RXFUNC | ET_MAC_CFG1_RESET_TXFUNC,
               &macregs->cfg1);

        /* Next lets configure the MAC Inter-packet gap register */
        ipg = 0x38005860;               /* IPG1 0x38 IPG2 0x58 B2B 0x60 */
        ipg |= 0x50 << 8;               /* ifg enforce 0x50 */
        writel(ipg, &macregs->ipg);

        /* Next lets configure the MAC Half Duplex register */
        /* BEB trunc 0xA, Ex Defer, Rexmit 0xF Coll 0x37 */
        writel(0x00A1F037, &macregs->hfdp);

        /* Next lets configure the MAC Interface Control register */
        writel(0, &macregs->if_ctrl);

        /* Let's move on to setting up the mii management configuration */
        writel(ET_MAC_MIIMGMT_CLK_RST, &macregs->mii_mgmt_cfg);

        /* Next lets configure the MAC Station Address register.  These
         * values are read from the EEPROM during initialization and stored
         * in the adapter structure.  We write what is stored in the adapter
         * structure to the MAC Station Address registers high and low.  This
         * station address is used for generating and checking pause control
         * packets.
         */
        station2 = (adapter->addr[1] << ET_MAC_STATION_ADDR2_OC2_SHIFT) |
                   (adapter->addr[0] << ET_MAC_STATION_ADDR2_OC1_SHIFT);
        station1 = (adapter->addr[5] << ET_MAC_STATION_ADDR1_OC6_SHIFT) |
                   (adapter->addr[4] << ET_MAC_STATION_ADDR1_OC5_SHIFT) |
                   (adapter->addr[3] << ET_MAC_STATION_ADDR1_OC4_SHIFT) |
                    adapter->addr[2];
        writel(station1, &macregs->station_addr_1);
        writel(station2, &macregs->station_addr_2);

        /* Max ethernet packet in bytes that will be passed by the mac without
         * being truncated.  Allow the MAC to pass 4 more than our max packet
         * size.  This is 4 for the Ethernet CRC.
         *
         * Packets larger than (registry_jumbo_packet) that do not contain a
         * VLAN ID will be dropped by the Rx function.
         */
        writel(adapter->registry_jumbo_packet + 4, &macregs->max_fm_len);

        /* clear out MAC config reset */
        writel(0, &macregs->cfg1);
}

/* et1310_config_mac_regs2 - Initialize the second part of MAC regs
 * @adapter: pointer to our adapter structure
 */
static void et1310_config_mac_regs2(struct et131x_adapter *adapter)
{
        int32_t delay = 0;
        struct mac_regs __iomem *mac = &adapter->regs->mac;
        struct phy_device *phydev = adapter->phydev;
        u32 cfg1;
        u32 cfg2;
        u32 ifctrl;
        u32 ctl;

        ctl = readl(&adapter->regs->txmac.ctl);
        cfg1 = readl(&mac->cfg1);
        cfg2 = readl(&mac->cfg2);
        ifctrl = readl(&mac->if_ctrl);

        /* Set up the if mode bits */
        cfg2 &= ~ET_MAC_CFG2_IFMODE_MASK;
        if (phydev->speed == SPEED_1000) {
                cfg2 |= ET_MAC_CFG2_IFMODE_1000;
                /* Phy mode bit */
                ifctrl &= ~ET_MAC_IFCTRL_PHYMODE;
        } else {
                cfg2 |= ET_MAC_CFG2_IFMODE_100;
                ifctrl |= ET_MAC_IFCTRL_PHYMODE;
        }

        /* We need to enable Rx/Tx */
        cfg1 |= ET_MAC_CFG1_RX_ENABLE | ET_MAC_CFG1_TX_ENABLE |
                                                        ET_MAC_CFG1_TX_FLOW;
        /* Initialize loop back to off */
        cfg1 &= ~(ET_MAC_CFG1_LOOPBACK | ET_MAC_CFG1_RX_FLOW);
        if (adapter->flowcontrol == FLOW_RXONLY ||
                                adapter->flowcontrol == FLOW_BOTH)
                cfg1 |= ET_MAC_CFG1_RX_FLOW;
        writel(cfg1, &mac->cfg1);

        /* Now we need to initialize the MAC Configuration 2 register */
        /* preamble 7, check length, huge frame off, pad crc, crc enable
         * full duplex off
         */
        cfg2 |= 0x7 << ET_MAC_CFG2_PREAMBLE_SHIFT;
        cfg2 |= ET_MAC_CFG2_IFMODE_LEN_CHECK;
        cfg2 |= ET_MAC_CFG2_IFMODE_PAD_CRC;
        cfg2 |= ET_MAC_CFG2_IFMODE_CRC_ENABLE;
        cfg2 &= ~ET_MAC_CFG2_IFMODE_HUGE_FRAME;
        cfg2 &= ~ET_MAC_CFG2_IFMODE_FULL_DPLX;

        /* Turn on duplex if needed */

        if (phydev->duplex == DUPLEX_FULL)
                cfg2 |= ET_MAC_CFG2_IFMODE_FULL_DPLX;

        ifctrl &= ~ET_MAC_IFCTRL_GHDMODE;
        if (phydev->duplex == DUPLEX_HALF)
                ifctrl |= ET_MAC_IFCTRL_GHDMODE;

        writel(ifctrl, &mac->if_ctrl);
        writel(cfg2, &mac->cfg2);

        do {
                udelay(10);
                delay++;
                cfg1 = readl(&mac->cfg1);
        } while ((cfg1 & ET_MAC_CFG1_WAIT) != ET_MAC_CFG1_WAIT && delay < 100);

        if (delay == 100) {
                dev_warn(&adapter->pdev->dev,
                    "Syncd bits did not respond correctly cfg1 word 0x%08x\n",
                        cfg1);
        }

        /* Enable txmac */
        ctl |= ET_TX_CTRL_TXMAC_ENABLE | ET_TX_CTRL_FC_DISABLE;
        writel(ctl, &adapter->regs->txmac.ctl);

        /* Ready to start the RXDMA/TXDMA engine */
        if (adapter->flags & FMP_ADAPTER_LOWER_POWER) {
                et131x_rx_dma_enable(adapter);
                et131x_tx_dma_enable(adapter);
        }
}

/* et1310_in_phy_coma - check if the device is in phy coma
 * @adapter: pointer to our adapter structure
 *
 * Returns 0 if the device is not in phy coma, 1 if it is in phy coma
 */
static int et1310_in_phy_coma(struct et131x_adapter *adapter)
{
        u32 pmcsr = readl(&adapter->regs->global.pm_csr);

        return ET_PM_PHY_SW_COMA & pmcsr ? 1 : 0;
}

static void et1310_setup_device_for_multicast(struct et131x_adapter *adapter)
{
        struct rxmac_regs __iomem *rxmac = &adapter->regs->rxmac;
        u32 hash1 = 0;
        u32 hash2 = 0;
        u32 hash3 = 0;
        u32 hash4 = 0;
        u32 pm_csr;

        /* If ET131X_PACKET_TYPE_MULTICAST is specified, then we provision
         * the multi-cast LIST.  If it is NOT specified, (and "ALL" is not
         * specified) then we should pass NO multi-cast addresses to the
         * driver.
         */
        if (adapter->packet_filter & ET131X_PACKET_TYPE_MULTICAST) {
                int i;

                /* Loop through our multicast array and set up the device */
                for (i = 0; i < adapter->multicast_addr_count; i++) {
                        u32 result;

                        result = ether_crc(6, adapter->multicast_list[i]);

                        result = (result & 0x3F800000) >> 23;

                        if (result < 32) {
                                hash1 |= (1 << result);
                        } else if ((31 < result) && (result < 64)) {
                                result -= 32;
                                hash2 |= (1 << result);
                        } else if ((63 < result) && (result < 96)) {
                                result -= 64;
                                hash3 |= (1 << result);
                        } else {
                                result -= 96;
                                hash4 |= (1 << result);
                        }
                }
        }

        /* Write out the new hash to the device */
        pm_csr = readl(&adapter->regs->global.pm_csr);
        if (!et1310_in_phy_coma(adapter)) {
                writel(hash1, &rxmac->multi_hash1);
                writel(hash2, &rxmac->multi_hash2);
                writel(hash3, &rxmac->multi_hash3);
                writel(hash4, &rxmac->multi_hash4);
        }
}

static void et1310_setup_device_for_unicast(struct et131x_adapter *adapter)
{
        struct rxmac_regs __iomem *rxmac = &adapter->regs->rxmac;
        u32 uni_pf1;
        u32 uni_pf2;
        u32 uni_pf3;
        u32 pm_csr;

        /* Set up unicast packet filter reg 3 to be the first two octets of
         * the MAC address for both address
         *
         * Set up unicast packet filter reg 2 to be the octets 2 - 5 of the
         * MAC address for second address
         *
         * Set up unicast packet filter reg 3 to be the octets 2 - 5 of the
         * MAC address for first address
         */
        uni_pf3 = (adapter->addr[0] << ET_RX_UNI_PF_ADDR2_1_SHIFT) |
                  (adapter->addr[1] << ET_RX_UNI_PF_ADDR2_2_SHIFT) |
                  (adapter->addr[0] << ET_RX_UNI_PF_ADDR1_1_SHIFT) |
                   adapter->addr[1];

        uni_pf2 = (adapter->addr[2] << ET_RX_UNI_PF_ADDR2_3_SHIFT) |
                  (adapter->addr[3] << ET_RX_UNI_PF_ADDR2_4_SHIFT) |
                  (adapter->addr[4] << ET_RX_UNI_PF_ADDR2_5_SHIFT) |
                   adapter->addr[5];

        uni_pf1 = (adapter->addr[2] << ET_RX_UNI_PF_ADDR1_3_SHIFT) |
                  (adapter->addr[3] << ET_RX_UNI_PF_ADDR1_4_SHIFT) |
                  (adapter->addr[4] << ET_RX_UNI_PF_ADDR1_5_SHIFT) |
                   adapter->addr[5];

        pm_csr = readl(&adapter->regs->global.pm_csr);
        if (!et1310_in_phy_coma(adapter)) {
                writel(uni_pf1, &rxmac->uni_pf_addr1);
                writel(uni_pf2, &rxmac->uni_pf_addr2);
                writel(uni_pf3, &rxmac->uni_pf_addr3);
        }
}

static void et1310_config_rxmac_regs(struct et131x_adapter *adapter)
{
        struct rxmac_regs __iomem *rxmac = &adapter->regs->rxmac;
        struct phy_device *phydev = adapter->phydev;
        u32 sa_lo;
        u32 sa_hi = 0;
        u32 pf_ctrl = 0;

        /* Disable the MAC while it is being configured (also disable WOL) */
        writel(0x8, &rxmac->ctrl);

        /* Initialize WOL to disabled. */
        writel(0, &rxmac->crc0);
        writel(0, &rxmac->crc12);
        writel(0, &rxmac->crc34);

        /* We need to set the WOL mask0 - mask4 next.  We initialize it to
         * its default Values of 0x00000000 because there are not WOL masks
         * as of this time.
         */
        writel(0, &rxmac->mask0_word0);
        writel(0, &rxmac->mask0_word1);
        writel(0, &rxmac->mask0_word2);
        writel(0, &rxmac->mask0_word3);

        writel(0, &rxmac->mask1_word0);
        writel(0, &rxmac->mask1_word1);
        writel(0, &rxmac->mask1_word2);
        writel(0, &rxmac->mask1_word3);

        writel(0, &rxmac->mask2_word0);
        writel(0, &rxmac->mask2_word1);
        writel(0, &rxmac->mask2_word2);
        writel(0, &rxmac->mask2_word3);

        writel(0, &rxmac->mask3_word0);
        writel(0, &rxmac->mask3_word1);
        writel(0, &rxmac->mask3_word2);
        writel(0, &rxmac->mask3_word3);

        writel(0, &rxmac->mask4_word0);
        writel(0, &rxmac->mask4_word1);
        writel(0, &rxmac->mask4_word2);
        writel(0, &rxmac->mask4_word3);

        /* Lets setup the WOL Source Address */
        sa_lo = (adapter->addr[2] << ET_RX_WOL_LO_SA3_SHIFT) |
                (adapter->addr[3] << ET_RX_WOL_LO_SA4_SHIFT) |
                (adapter->addr[4] << ET_RX_WOL_LO_SA5_SHIFT) |
                 adapter->addr[5];
        writel(sa_lo, &rxmac->sa_lo);

        sa_hi = (u32) (adapter->addr[0] << ET_RX_WOL_HI_SA1_SHIFT) |
                       adapter->addr[1];
        writel(sa_hi, &rxmac->sa_hi);

        /* Disable all Packet Filtering */
        writel(0, &rxmac->pf_ctrl);

        /* Let's initialize the Unicast Packet filtering address */
        if (adapter->packet_filter & ET131X_PACKET_TYPE_DIRECTED) {
                et1310_setup_device_for_unicast(adapter);
                pf_ctrl |= ET_RX_PFCTRL_UNICST_FILTER_ENABLE;
        } else {
                writel(0, &rxmac->uni_pf_addr1);
                writel(0, &rxmac->uni_pf_addr2);
                writel(0, &rxmac->uni_pf_addr3);
        }

        /* Let's initialize the Multicast hash */
        if (!(adapter->packet_filter & ET131X_PACKET_TYPE_ALL_MULTICAST)) {
                pf_ctrl |= ET_RX_PFCTRL_MLTCST_FILTER_ENABLE;
                et1310_setup_device_for_multicast(adapter);
        }

        /* Runt packet filtering.  Didn't work in version A silicon. */
        pf_ctrl |= (NIC_MIN_PACKET_SIZE + 4) << ET_RX_PFCTRL_MIN_PKT_SZ_SHIFT;
        pf_ctrl |= ET_RX_PFCTRL_FRAG_FILTER_ENABLE;

        if (adapter->registry_jumbo_packet > 8192)
                /* In order to transmit jumbo packets greater than 8k, the
                 * FIFO between RxMAC and RxDMA needs to be reduced in size
                 * to (16k - Jumbo packet size).  In order to implement this,
                 * we must use "cut through" mode in the RxMAC, which chops
                 * packets down into segments which are (max_size * 16).  In
                 * this case we selected 256 bytes, since this is the size of
                 * the PCI-Express TLP's that the 1310 uses.
                 *
                 * seg_en on, fc_en off, size 0x10
                 */
                writel(0x41, &rxmac->mcif_ctrl_max_seg);
        else
                writel(0, &rxmac->mcif_ctrl_max_seg);

        /* Initialize the MCIF water marks */
        writel(0, &rxmac->mcif_water_mark);

        /*  Initialize the MIF control */
        writel(0, &rxmac->mif_ctrl);

        /* Initialize the Space Available Register */
        writel(0, &rxmac->space_avail);

        /* Initialize the the mif_ctrl register
         * bit 3:  Receive code error. One or more nibbles were signaled as
         *         errors  during the reception of the packet.  Clear this
         *         bit in Gigabit, set it in 100Mbit.  This was derived
         *         experimentally at UNH.
         * bit 4:  Receive CRC error. The packet's CRC did not match the
         *         internally generated CRC.
         * bit 5:  Receive length check error. Indicates that frame length
         *         field value in the packet does not match the actual data
         *         byte length and is not a type field.
         * bit 16: Receive frame truncated.
         * bit 17: Drop packet enable
         */
        if (phydev && phydev->speed == SPEED_100)
                writel(0x30038, &rxmac->mif_ctrl);
        else
                writel(0x30030, &rxmac->mif_ctrl);

        /* Finally we initialize RxMac to be enabled & WOL disabled.  Packet
         * filter is always enabled since it is where the runt packets are
         * supposed to be dropped.  For version A silicon, runt packet
         * dropping doesn't work, so it is disabled in the pf_ctrl register,
         * but we still leave the packet filter on.
         */
        writel(pf_ctrl, &rxmac->pf_ctrl);
        writel(ET_RX_CTRL_RXMAC_ENABLE | ET_RX_CTRL_WOL_DISABLE, &rxmac->ctrl);
}

static void et1310_config_txmac_regs(struct et131x_adapter *adapter)
{
        struct txmac_regs __iomem *txmac = &adapter->regs->txmac;

        /* We need to update the Control Frame Parameters
         * cfpt - control frame pause timer set to 64 (0x40)
         * cfep - control frame extended pause timer set to 0x0
         */
        if (adapter->flowcontrol == FLOW_NONE)
                writel(0, &txmac->cf_param);
        else
                writel(0x40, &txmac->cf_param);
}

static void et1310_config_macstat_regs(struct et131x_adapter *adapter)
{
        struct macstat_regs __iomem *macstat =
                &adapter->regs->macstat;

        /* Next we need to initialize all the macstat registers to zero on
         * the device.
         */
        writel(0, &macstat->txrx_0_64_byte_frames);
        writel(0, &macstat->txrx_65_127_byte_frames);
        writel(0, &macstat->txrx_128_255_byte_frames);
        writel(0, &macstat->txrx_256_511_byte_frames);
        writel(0, &macstat->txrx_512_1023_byte_frames);
        writel(0, &macstat->txrx_1024_1518_byte_frames);
        writel(0, &macstat->txrx_1519_1522_gvln_frames);

        writel(0, &macstat->rx_bytes);
        writel(0, &macstat->rx_packets);
        writel(0, &macstat->rx_fcs_errs);
        writel(0, &macstat->rx_multicast_packets);
        writel(0, &macstat->rx_broadcast_packets);
        writel(0, &macstat->rx_control_frames);
        writel(0, &macstat->rx_pause_frames);
        writel(0, &macstat->rx_unknown_opcodes);
        writel(0, &macstat->rx_align_errs);
        writel(0, &macstat->rx_frame_len_errs);
        writel(0, &macstat->rx_code_errs);
        writel(0, &macstat->rx_carrier_sense_errs);
        writel(0, &macstat->rx_undersize_packets);
        writel(0, &macstat->rx_oversize_packets);
        writel(0, &macstat->rx_fragment_packets);
        writel(0, &macstat->rx_jabbers);
        writel(0, &macstat->rx_drops);

        writel(0, &macstat->tx_bytes);
        writel(0, &macstat->tx_packets);
        writel(0, &macstat->tx_multicast_packets);
        writel(0, &macstat->tx_broadcast_packets);
        writel(0, &macstat->tx_pause_frames);
        writel(0, &macstat->tx_deferred);
        writel(0, &macstat->tx_excessive_deferred);
        writel(0, &macstat->tx_single_collisions);
        writel(0, &macstat->tx_multiple_collisions);
        writel(0, &macstat->tx_late_collisions);
        writel(0, &macstat->tx_excessive_collisions);
        writel(0, &macstat->tx_total_collisions);
        writel(0, &macstat->tx_pause_honored_frames);
        writel(0, &macstat->tx_drops);
        writel(0, &macstat->tx_jabbers);
        writel(0, &macstat->tx_fcs_errs);
        writel(0, &macstat->tx_control_frames);
        writel(0, &macstat->tx_oversize_frames);
        writel(0, &macstat->tx_undersize_frames);
        writel(0, &macstat->tx_fragments);
        writel(0, &macstat->carry_reg1);
        writel(0, &macstat->carry_reg2);

        /* Unmask any counters that we want to track the overflow of.
         * Initially this will be all counters.  It may become clear later
         * that we do not need to track all counters.
         */
        writel(0xFFFFBE32, &macstat->carry_reg1_mask);
        writel(0xFFFE7E8B, &macstat->carry_reg2_mask);
}

/* et131x_phy_mii_read - Read from the PHY through the MII Interface on the MAC
 * @adapter: pointer to our private adapter structure
 * @addr: the address of the transceiver
 * @reg: the register to read
 * @value: pointer to a 16-bit value in which the value will be stored
 */
static int et131x_phy_mii_read(struct et131x_adapter *adapter, u8 addr,
              u8 reg, u16 *value)
{
        struct mac_regs __iomem *mac = &adapter->regs->mac;
        int status = 0;
        u32 delay = 0;
        u32 mii_addr;
        u32 mii_cmd;
        u32 mii_indicator;

        /* Save a local copy of the registers we are dealing with so we can
         * set them back
         */
        mii_addr = readl(&mac->mii_mgmt_addr);
        mii_cmd = readl(&mac->mii_mgmt_cmd);

        /* Stop the current operation */
        writel(0, &mac->mii_mgmt_cmd);

        /* Set up the register we need to read from on the correct PHY */
        writel(ET_MAC_MII_ADDR(addr, reg), &mac->mii_mgmt_addr);

        writel(0x1, &mac->mii_mgmt_cmd);

        do {
                udelay(50);
                delay++;
                mii_indicator = readl(&mac->mii_mgmt_indicator);
        } while ((mii_indicator & ET_MAC_MGMT_WAIT) && delay < 50);

        /* If we hit the max delay, we could not read the register */
        if (delay == 50) {
                dev_warn(&adapter->pdev->dev,
                            "reg 0x%08x could not be read\n", reg);
                dev_warn(&adapter->pdev->dev, "status is  0x%08x\n",
                            mii_indicator);

                status = -EIO;
                goto out;
        }

        /* If we hit here we were able to read the register and we need to
         * return the value to the caller
         */
        *value = readl(&mac->mii_mgmt_stat) & ET_MAC_MIIMGMT_STAT_PHYCRTL_MASK;

out:
        /* Stop the read operation */
        writel(0, &mac->mii_mgmt_cmd);

        /* set the registers we touched back to the state at which we entered
         * this function
         */
        writel(mii_addr, &mac->mii_mgmt_addr);
        writel(mii_cmd, &mac->mii_mgmt_cmd);

        return status;
}

static int et131x_mii_read(struct et131x_adapter *adapter, u8 reg, u16 *value)
{
        struct phy_device *phydev = adapter->phydev;

        if (!phydev)
                return -EIO;

        return et131x_phy_mii_read(adapter, phydev->addr, reg, value);
}

/* et131x_mii_write - Write to a PHY reg through the MII interface of the MAC
 * @adapter: pointer to our private adapter structure
 * @reg: the register to read
 * @value: 16-bit value to write
 */
static int et131x_mii_write(struct et131x_adapter *adapter, u8 reg, u16 value)
{
        struct mac_regs __iomem *mac = &adapter->regs->mac;
        struct phy_device *phydev = adapter->phydev;
        int status = 0;
        u8 addr;
        u32 delay = 0;
        u32 mii_addr;
        u32 mii_cmd;
        u32 mii_indicator;

        if (!phydev)
                return -EIO;

        addr = phydev->addr;

        /* Save a local copy of the registers we are dealing with so we can
         * set them back
         */
        mii_addr = readl(&mac->mii_mgmt_addr);
        mii_cmd = readl(&mac->mii_mgmt_cmd);

        /* Stop the current operation */
        writel(0, &mac->mii_mgmt_cmd);

        /* Set up the register we need to write to on the correct PHY */
        writel(ET_MAC_MII_ADDR(addr, reg), &mac->mii_mgmt_addr);

        /* Add the value to write to the registers to the mac */
        writel(value, &mac->mii_mgmt_ctrl);

        do {
                udelay(50);
                delay++;
                mii_indicator = readl(&mac->mii_mgmt_indicator);
        } while ((mii_indicator & ET_MAC_MGMT_BUSY) && delay < 100);

        /* If we hit the max delay, we could not write the register */
        if (delay == 100) {
                u16 tmp;

                dev_warn(&adapter->pdev->dev,
                    "reg 0x%08x could not be written", reg);
                dev_warn(&adapter->pdev->dev, "status is  0x%08x\n",
                            mii_indicator);
                dev_warn(&adapter->pdev->dev, "command is  0x%08x\n",
                            readl(&mac->mii_mgmt_cmd));

                et131x_mii_read(adapter, reg, &tmp);

                status = -EIO;
        }
        /* Stop the write operation */
        writel(0, &mac->mii_mgmt_cmd);

        /* set the registers we touched back to the state at which we entered
         * this function
         */
        writel(mii_addr, &mac->mii_mgmt_addr);
        writel(mii_cmd, &mac->mii_mgmt_cmd);

        return status;
}

static void et1310_phy_read_mii_bit(struct et131x_adapter *adapter,
                                    u16 regnum,
                                    u16 bitnum,
                                    u8 *value)
{
        u16 reg;
        u16 mask = 1 << bitnum;

        /* Read the requested register */
        et131x_mii_read(adapter, regnum, &reg);

        *value = (reg & mask) >> bitnum;
}

static void et1310_config_flow_control(struct et131x_adapter *adapter)
{
        struct phy_device *phydev = adapter->phydev;

        if (phydev->duplex == DUPLEX_HALF) {
                adapter->flowcontrol = FLOW_NONE;
        } else {
                char remote_pause, remote_async_pause;

                et1310_phy_read_mii_bit(adapter, 5, 10, &remote_pause);
                et1310_phy_read_mii_bit(adapter, 5, 11, &remote_async_pause);

                if (remote_pause && remote_async_pause) {
                        adapter->flowcontrol = adapter->wanted_flow;
                } else if (remote_pause && !remote_async_pause) {
                        if (adapter->wanted_flow == FLOW_BOTH)
                                adapter->flowcontrol = FLOW_BOTH;
                        else
                                adapter->flowcontrol = FLOW_NONE;
                } else if (!remote_pause && !remote_async_pause) {
                        adapter->flowcontrol = FLOW_NONE;
                } else {
                        if (adapter->wanted_flow == FLOW_BOTH)
                                adapter->flowcontrol = FLOW_RXONLY;
                        else
                                adapter->flowcontrol = FLOW_NONE;
                }
        }
}

/* et1310_update_macstat_host_counters - Update local copy of the statistics */
static void et1310_update_macstat_host_counters(struct et131x_adapter *adapter)
{
        struct ce_stats *stats = &adapter->stats;
        struct macstat_regs __iomem *macstat =
                &adapter->regs->macstat;

        stats->tx_collisions           += readl(&macstat->tx_total_collisions);
        stats->tx_first_collisions     += readl(&macstat->tx_single_collisions);
        stats->tx_deferred             += readl(&macstat->tx_deferred);
        stats->tx_excessive_collisions +=
                                readl(&macstat->tx_multiple_collisions);
        stats->tx_late_collisions      += readl(&macstat->tx_late_collisions);
        stats->tx_underflows           += readl(&macstat->tx_undersize_frames);
        stats->tx_max_pkt_errs         += readl(&macstat->tx_oversize_frames);

        stats->rx_align_errs        += readl(&macstat->rx_align_errs);
        stats->rx_crc_errs          += readl(&macstat->rx_code_errs);
        stats->rcvd_pkts_dropped    += readl(&macstat->rx_drops);
        stats->rx_overflows         += readl(&macstat->rx_oversize_packets);
        stats->rx_code_violations   += readl(&macstat->rx_fcs_errs);
        stats->rx_length_errs       += readl(&macstat->rx_frame_len_errs);
        stats->rx_other_errs        += readl(&macstat->rx_fragment_packets);
}

/* et1310_handle_macstat_interrupt
 *
 * One of the MACSTAT counters has wrapped.  Update the local copy of
 * the statistics held in the adapter structure, checking the "wrap"
 * bit for each counter.
 */
static void et1310_handle_macstat_interrupt(struct et131x_adapter *adapter)
{
        u32 carry_reg1;
        u32 carry_reg2;

        /* Read the interrupt bits from the register(s).  These are Clear On
         * Write.
         */
        carry_reg1 = readl(&adapter->regs->macstat.carry_reg1);
        carry_reg2 = readl(&adapter->regs->macstat.carry_reg2);

        writel(carry_reg1, &adapter->regs->macstat.carry_reg1);
        writel(carry_reg2, &adapter->regs->macstat.carry_reg2);

        /* We need to do update the host copy of all the MAC_STAT counters.
         * For each counter, check it's overflow bit.  If the overflow bit is
         * set, then increment the host version of the count by one complete
         * revolution of the counter.  This routine is called when the counter
         * block indicates that one of the counters has wrapped.
         */
        if (carry_reg1 & (1 << 14))
                adapter->stats.rx_code_violations       += COUNTER_WRAP_16_BIT;
        if (carry_reg1 & (1 << 8))
                adapter->stats.rx_align_errs    += COUNTER_WRAP_12_BIT;
        if (carry_reg1 & (1 << 7))
                adapter->stats.rx_length_errs   += COUNTER_WRAP_16_BIT;
        if (carry_reg1 & (1 << 2))
                adapter->stats.rx_other_errs    += COUNTER_WRAP_16_BIT;
        if (carry_reg1 & (1 << 6))
                adapter->stats.rx_crc_errs      += COUNTER_WRAP_16_BIT;
        if (carry_reg1 & (1 << 3))
                adapter->stats.rx_overflows     += COUNTER_WRAP_16_BIT;
        if (carry_reg1 & (1 << 0))
                adapter->stats.rcvd_pkts_dropped        += COUNTER_WRAP_16_BIT;
        if (carry_reg2 & (1 << 16))
                adapter->stats.tx_max_pkt_errs  += COUNTER_WRAP_12_BIT;
        if (carry_reg2 & (1 << 15))
                adapter->stats.tx_underflows    += COUNTER_WRAP_12_BIT;
        if (carry_reg2 & (1 << 6))
                adapter->stats.tx_first_collisions += COUNTER_WRAP_12_BIT;
        if (carry_reg2 & (1 << 8))
                adapter->stats.tx_deferred      += COUNTER_WRAP_12_BIT;
        if (carry_reg2 & (1 << 5))
                adapter->stats.tx_excessive_collisions += COUNTER_WRAP_12_BIT;
        if (carry_reg2 & (1 << 4))
                adapter->stats.tx_late_collisions       += COUNTER_WRAP_12_BIT;
        if (carry_reg2 & (1 << 2))
                adapter->stats.tx_collisions    += COUNTER_WRAP_12_BIT;
}

static int et131x_mdio_read(struct mii_bus *bus, int phy_addr, int reg)
{
        struct net_device *netdev = bus->priv;
        struct et131x_adapter *adapter = netdev_priv(netdev);
        u16 value;
        int ret;

        ret = et131x_phy_mii_read(adapter, phy_addr, reg, &value);

        if (ret < 0)
                return ret;
        else
                return value;
}

static int et131x_mdio_write(struct mii_bus *bus, int phy_addr,
                             int reg, u16 value)
{
        struct net_device *netdev = bus->priv;
        struct et131x_adapter *adapter = netdev_priv(netdev);

        return et131x_mii_write(adapter, reg, value);
}

static int et131x_mdio_reset(struct mii_bus *bus)
{
        struct net_device *netdev = bus->priv;
        struct et131x_adapter *adapter = netdev_priv(netdev);

        et131x_mii_write(adapter, MII_BMCR, BMCR_RESET);

        return 0;
}

/*      et1310_phy_power_switch -       PHY power control
 *      @adapter: device to control
 *      @down: true for off/false for back on
 *
 *      one hundred, ten, one thousand megs
 *      How would you like to have your LAN accessed
 *      Can't you see that this code processed
 *      Phy power, phy power..
 */
static void et1310_phy_power_switch(struct et131x_adapter *adapter, bool down)
{
        u16 data;

        et131x_mii_read(adapter, MII_BMCR, &data);
        data &= ~BMCR_PDOWN;
        if (down)
                data |= BMCR_PDOWN;
        et131x_mii_write(adapter, MII_BMCR, data);
}

/* et131x_xcvr_init - Init the phy if we are setting it into force mode */
static void et131x_xcvr_init(struct et131x_adapter *adapter)
{
        u16 lcr2;

        /* Set the LED behavior such that LED 1 indicates speed (off =
         * 10Mbits, blink = 100Mbits, on = 1000Mbits) and LED 2 indicates
         * link and activity (on for link, blink off for activity).
         *
         * NOTE: Some customizations have been added here for specific
         * vendors; The LED behavior is now determined by vendor data in the
         * EEPROM. However, the above description is the default.
         */
        if ((adapter->eeprom_data[1] & 0x4) == 0) {
                et131x_mii_read(adapter, PHY_LED_2, &lcr2);

                lcr2 &= (ET_LED2_LED_100TX | ET_LED2_LED_1000T);
                lcr2 |= (LED_VAL_LINKON_ACTIVE << LED_LINK_SHIFT);

                if ((adapter->eeprom_data[1] & 0x8) == 0)
                        lcr2 |= (LED_VAL_1000BT_100BTX << LED_TXRX_SHIFT);
                else
                        lcr2 |= (LED_VAL_LINKON << LED_TXRX_SHIFT);

                et131x_mii_write(adapter, PHY_LED_2, lcr2);
        }
}

/* et131x_configure_global_regs - configure JAGCore global regs
 *
 * Used to configure the global registers on the JAGCore
 */
static void et131x_configure_global_regs(struct et131x_adapter *adapter)
{
        struct global_regs __iomem *regs = &adapter->regs->global;

        writel(0, &regs->rxq_start_addr);
        writel(INTERNAL_MEM_SIZE - 1, &regs->txq_end_addr);

        if (adapter->registry_jumbo_packet < 2048) {
                /* Tx / RxDMA and Tx/Rx MAC interfaces have a 1k word
                 * block of RAM that the driver can split between Tx
                 * and Rx as it desires.  Our default is to split it
                 * 50/50:
                 */
                writel(PARM_RX_MEM_END_DEF, &regs->rxq_end_addr);
                writel(PARM_RX_MEM_END_DEF + 1, &regs->txq_start_addr);
        } else if (adapter->registry_jumbo_packet < 8192) {
                /* For jumbo packets > 2k but < 8k, split 50-50. */
                writel(INTERNAL_MEM_RX_OFFSET, &regs->rxq_end_addr);
                writel(INTERNAL_MEM_RX_OFFSET + 1, &regs->txq_start_addr);
        } else {
                /* 9216 is the only packet size greater than 8k that
                 * is available. The Tx buffer has to be big enough
                 * for one whole packet on the Tx side. We'll make
                 * the Tx 9408, and give the rest to Rx
                 */
                writel(0x01b3, &regs->rxq_end_addr);
                writel(0x01b4, &regs->txq_start_addr);
        }

        /* Initialize the loopback register. Disable all loopbacks. */
        writel(0, &regs->loopback);

        /* MSI Register */
        writel(0, &regs->msi_config);

        /* By default, disable the watchdog timer.  It will be enabled when
         * a packet is queued.
         */
        writel(0, &regs->watchdog_timer);
}

/* et131x_config_rx_dma_regs - Start of Rx_DMA init sequence */
static void et131x_config_rx_dma_regs(struct et131x_adapter *adapter)
{
        struct rxdma_regs __iomem *rx_dma = &adapter->regs->rxdma;
        struct rx_ring *rx_local = &adapter->rx_ring;
        struct fbr_desc *fbr_entry;
        u32 entry;
        u32 psr_num_des;
        unsigned long flags;
        u8 id;

        /* Halt RXDMA to perform the reconfigure.  */
        et131x_rx_dma_disable(adapter);

        /* Load the completion writeback physical address */
        writel(upper_32_bits(rx_local->rx_status_bus), &rx_dma->dma_wb_base_hi);
        writel(lower_32_bits(rx_local->rx_status_bus), &rx_dma->dma_wb_base_lo);

        memset(rx_local->rx_status_block, 0, sizeof(struct rx_status_block));

        /* Set the address and parameters of the packet status ring into the
         * 1310's registers
         */
        writel(upper_32_bits(rx_local->ps_ring_physaddr), &rx_dma->psr_base_hi);
        writel(lower_32_bits(rx_local->ps_ring_physaddr), &rx_dma->psr_base_lo);
        writel(rx_local->psr_num_entries - 1, &rx_dma->psr_num_des);
        writel(0, &rx_dma->psr_full_offset);

        psr_num_des = readl(&rx_dma->psr_num_des) & ET_RXDMA_PSR_NUM_DES_MASK;
        writel((psr_num_des * LO_MARK_PERCENT_FOR_PSR) / 100,
               &rx_dma->psr_min_des);

        spin_lock_irqsave(&adapter->rcv_lock, flags);

        /* These local variables track the PSR in the adapter structure */
        rx_local->local_psr_full = 0;

        for (id = 0; id < NUM_FBRS; id++) {
                u32 __iomem *num_des;
                u32 __iomem *full_offset;
                u32 __iomem *min_des;
                u32 __iomem *base_hi;
                u32 __iomem *base_lo;
                struct fbr_lookup *fbr = rx_local->fbr[id];

                if (id == 0) {
                        num_des = &rx_dma->fbr0_num_des;
                        full_offset = &rx_dma->fbr0_full_offset;
                        min_des = &rx_dma->fbr0_min_des;
                        base_hi = &rx_dma->fbr0_base_hi;
                        base_lo = &rx_dma->fbr0_base_lo;
                } else {
                        num_des = &rx_dma->fbr1_num_des;
                        full_offset = &rx_dma->fbr1_full_offset;
                        min_des = &rx_dma->fbr1_min_des;
                        base_hi = &rx_dma->fbr1_base_hi;
                        base_lo = &rx_dma->fbr1_base_lo;
                }

                /* Now's the best time to initialize FBR contents */
                fbr_entry = fbr->ring_virtaddr;
                for (entry = 0; entry < fbr->num_entries; entry++) {
                        fbr_entry->addr_hi = fbr->bus_high[entry];
                        fbr_entry->addr_lo = fbr->bus_low[entry];
                        fbr_entry->word2 = entry;
                        fbr_entry++;
                }

                /* Set the address and parameters of Free buffer ring 1 and 0
                 * into the 1310's registers
                 */
                writel(upper_32_bits(fbr->ring_physaddr), base_hi);
                writel(lower_32_bits(fbr->ring_physaddr), base_lo);
                writel(fbr->num_entries - 1, num_des);
                writel(ET_DMA10_WRAP, full_offset);

                /* This variable tracks the free buffer ring 1 full position,
                 * so it has to match the above.
                 */
                fbr->local_full = ET_DMA10_WRAP;
                writel(((fbr->num_entries * LO_MARK_PERCENT_FOR_RX) / 100) - 1,
                       min_des);
        }

        /* Program the number of packets we will receive before generating an
         * interrupt.
         * For version B silicon, this value gets updated once autoneg is
         *complete.
         */
        writel(PARM_RX_NUM_BUFS_DEF, &rx_dma->num_pkt_done);

        /* The "time_done" is not working correctly to coalesce interrupts
         * after a given time period, but rather is giving us an interrupt
         * regardless of whether we have received packets.
         * This value gets updated once autoneg is complete.
         */
        writel(PARM_RX_TIME_INT_DEF, &rx_dma->max_pkt_time);

        spin_unlock_irqrestore(&adapter->rcv_lock, flags);
}

/* et131x_config_tx_dma_regs - Set up the tx dma section of the JAGCore.
 *
 * Configure the transmit engine with the ring buffers we have created
 * and prepare it for use.
 */
static void et131x_config_tx_dma_regs(struct et131x_adapter *adapter)
{
        struct txdma_regs __iomem *txdma = &adapter->regs->txdma;
        struct tx_ring *tx_ring = &adapter->tx_ring;

        /* Load the hardware with the start of the transmit descriptor ring. */
        writel(upper_32_bits(tx_ring->tx_desc_ring_pa), &txdma->pr_base_hi);
        writel(lower_32_bits(tx_ring->tx_desc_ring_pa), &txdma->pr_base_lo);

        /* Initialise the transmit DMA engine */
        writel(NUM_DESC_PER_RING_TX - 1, &txdma->pr_num_des);

        /* Load the completion writeback physical address */
        writel(upper_32_bits(tx_ring->tx_status_pa), &txdma->dma_wb_base_hi);
        writel(lower_32_bits(tx_ring->tx_status_pa), &txdma->dma_wb_base_lo);

        *tx_ring->tx_status = 0;

        writel(0, &txdma->service_request);
        tx_ring->send_idx = 0;
}

/* et131x_adapter_setup - Set the adapter up as per cassini+ documentation */
static void et131x_adapter_setup(struct et131x_adapter *adapter)
{
        /* Configure the JAGCore */
        et131x_configure_global_regs(adapter);

        et1310_config_mac_regs1(adapter);

        /* Configure the MMC registers */
        /* All we need to do is initialize the Memory Control Register */
        writel(ET_MMC_ENABLE, &adapter->regs->mmc.mmc_ctrl);

        et1310_config_rxmac_regs(adapter);
        et1310_config_txmac_regs(adapter);

        et131x_config_rx_dma_regs(adapter);
        et131x_config_tx_dma_regs(adapter);

        et1310_config_macstat_regs(adapter);

        et1310_phy_power_switch(adapter, 0);
        et131x_xcvr_init(adapter);
}

/* et131x_soft_reset - Issue soft reset to the hardware, complete for ET1310 */
static void et131x_soft_reset(struct et131x_adapter *adapter)
{
        u32 reg;

        /* Disable MAC Core */
        reg = ET_MAC_CFG1_SOFT_RESET | ET_MAC_CFG1_SIM_RESET |
              ET_MAC_CFG1_RESET_RXMC | ET_MAC_CFG1_RESET_TXMC |
              ET_MAC_CFG1_RESET_RXFUNC | ET_MAC_CFG1_RESET_TXFUNC;
        writel(reg, &adapter->regs->mac.cfg1);

        reg = ET_RESET_ALL;
        writel(reg, &adapter->regs->global.sw_reset);

        reg = ET_MAC_CFG1_RESET_RXMC | ET_MAC_CFG1_RESET_TXMC |
              ET_MAC_CFG1_RESET_RXFUNC | ET_MAC_CFG1_RESET_TXFUNC;
        writel(reg, &adapter->regs->mac.cfg1);
        writel(0, &adapter->regs->mac.cfg1);
}

/*      et131x_enable_interrupts        -       enable interrupt
 *
 *      Enable the appropriate interrupts on the ET131x according to our
 *      configuration
 */
static void et131x_enable_interrupts(struct et131x_adapter *adapter)
{
        u32 mask;

        /* Enable all global interrupts */
        if (adapter->flowcontrol == FLOW_TXONLY ||
            adapter->flowcontrol == FLOW_BOTH)
                mask = INT_MASK_ENABLE;
        else
                mask = INT_MASK_ENABLE_NO_FLOW;

        writel(mask, &adapter->regs->global.int_mask);
}

/*      et131x_disable_interrupts       -       interrupt disable
 *
 *      Block all interrupts from the et131x device at the device itself
 */
static void et131x_disable_interrupts(struct et131x_adapter *adapter)
{
        /* Disable all global interrupts */
        writel(INT_MASK_DISABLE, &adapter->regs->global.int_mask);
}

/* et131x_tx_dma_disable - Stop of Tx_DMA on the ET1310 */
static void et131x_tx_dma_disable(struct et131x_adapter *adapter)
{
        /* Setup the tramsmit dma configuration register */
        writel(ET_TXDMA_CSR_HALT | ET_TXDMA_SNGL_EPKT,
                                        &adapter->regs->txdma.csr);
}

/* et131x_enable_txrx - Enable tx/rx queues */
static void et131x_enable_txrx(struct net_device *netdev)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);

        /* Enable the Tx and Rx DMA engines (if not already enabled) */
        et131x_rx_dma_enable(adapter);
        et131x_tx_dma_enable(adapter);

        /* Enable device interrupts */
        if (adapter->flags & FMP_ADAPTER_INTERRUPT_IN_USE)
                et131x_enable_interrupts(adapter);

        /* We're ready to move some data, so start the queue */
        netif_start_queue(netdev);
}

/* et131x_disable_txrx - Disable tx/rx queues */
static void et131x_disable_txrx(struct net_device *netdev)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);

        /* First thing is to stop the queue */
        netif_stop_queue(netdev);

        /* Stop the Tx and Rx DMA engines */
        et131x_rx_dma_disable(adapter);
        et131x_tx_dma_disable(adapter);

        /* Disable device interrupts */
        et131x_disable_interrupts(adapter);
}

/* et131x_init_send - Initialize send data structures */
static void et131x_init_send(struct et131x_adapter *adapter)
{
        u32 ct;
        struct tx_ring *tx_ring = &adapter->tx_ring;
        struct tcb *tcb = tx_ring->tcb_ring;

        tx_ring->tcb_qhead = tcb;

        memset(tcb, 0, sizeof(struct tcb) * NUM_TCB);

        /* Go through and set up each TCB */
        for (ct = 0; ct++ < NUM_TCB; tcb++)
                /* Set the link pointer in HW TCB to the next TCB in the
                 * chain
                 */
                tcb->next = tcb + 1;

        /* Set the  tail pointer */
        tcb--;
        tx_ring->tcb_qtail = tcb;
        tcb->next = NULL;
        /* Curr send queue should now be empty */
        tx_ring->send_head = NULL;
        tx_ring->send_tail = NULL;
}

/* et1310_enable_phy_coma - called when network cable is unplugged
 *
 * driver receive an phy status change interrupt while in D0 and check that
 * phy_status is down.
 *
 *          -- gate off JAGCore;
 *          -- set gigE PHY in Coma mode
 *          -- wake on phy_interrupt; Perform software reset JAGCore,
 *             re-initialize jagcore and gigE PHY
 *
 *      Add D0-ASPM-PhyLinkDown Support:
 *          -- while in D0, when there is a phy_interrupt indicating phy link
 *             down status, call the MPSetPhyComa routine to enter this active
 *             state power saving mode
 *          -- while in D0-ASPM-PhyLinkDown mode, when there is a phy_interrupt
 *       indicating linkup status, call the MPDisablePhyComa routine to
 *             restore JAGCore and gigE PHY
 */
static void et1310_enable_phy_coma(struct et131x_adapter *adapter)
{
        unsigned long flags;
        u32 pmcsr;

        pmcsr = readl(&adapter->regs->global.pm_csr);

        /* Save the GbE PHY speed and duplex modes. Need to restore this
         * when cable is plugged back in
         */

        /* Stop sending packets. */
        spin_lock_irqsave(&adapter->send_hw_lock, flags);
        adapter->flags |= FMP_ADAPTER_LOWER_POWER;
        spin_unlock_irqrestore(&adapter->send_hw_lock, flags);

        /* Wait for outstanding Receive packets */

        et131x_disable_txrx(adapter->netdev);

        /* Gate off JAGCore 3 clock domains */
        pmcsr &= ~ET_PMCSR_INIT;
        writel(pmcsr, &adapter->regs->global.pm_csr);

        /* Program gigE PHY in to Coma mode */
        pmcsr |= ET_PM_PHY_SW_COMA;
        writel(pmcsr, &adapter->regs->global.pm_csr);
}

/* et1310_disable_phy_coma - Disable the Phy Coma Mode */
static void et1310_disable_phy_coma(struct et131x_adapter *adapter)
{
        u32 pmcsr;

        pmcsr = readl(&adapter->regs->global.pm_csr);

        /* Disable phy_sw_coma register and re-enable JAGCore clocks */
        pmcsr |= ET_PMCSR_INIT;
        pmcsr &= ~ET_PM_PHY_SW_COMA;
        writel(pmcsr, &adapter->regs->global.pm_csr);

        /* Restore the GbE PHY speed and duplex modes;
         * Reset JAGCore; re-configure and initialize JAGCore and gigE PHY
         */

        /* Re-initialize the send structures */
        et131x_init_send(adapter);

        /* Bring the device back to the state it was during init prior to
         * autonegotiation being complete.  This way, when we get the auto-neg
         * complete interrupt, we can complete init by calling ConfigMacREGS2.
         */
        et131x_soft_reset(adapter);

        /* setup et1310 as per the documentation ?? */
        et131x_adapter_setup(adapter);

        /* Allow Tx to restart */
        adapter->flags &= ~FMP_ADAPTER_LOWER_POWER;

        et131x_enable_txrx(adapter->netdev);
}

static inline u32 bump_free_buff_ring(u32 *free_buff_ring, u32 limit)
{
        u32 tmp_free_buff_ring = *free_buff_ring;

        tmp_free_buff_ring++;
        /* This works for all cases where limit < 1024. The 1023 case
         * works because 1023++ is 1024 which means the if condition is not
         * taken but the carry of the bit into the wrap bit toggles the wrap
         * value correctly
         */
        if ((tmp_free_buff_ring & ET_DMA10_MASK) > limit) {
                tmp_free_buff_ring &= ~ET_DMA10_MASK;
                tmp_free_buff_ring ^= ET_DMA10_WRAP;
        }
        /* For the 1023 case */
        tmp_free_buff_ring &= (ET_DMA10_MASK | ET_DMA10_WRAP);
        *free_buff_ring = tmp_free_buff_ring;
        return tmp_free_buff_ring;
}

/* et131x_rx_dma_memory_alloc
 *
 * Allocates Free buffer ring 1 for sure, free buffer ring 0 if required,
 * and the Packet Status Ring.
 */
static int et131x_rx_dma_memory_alloc(struct et131x_adapter *adapter)
{
        u8 id;
        u32 i, j;
        u32 bufsize;
        u32 pktstat_ringsize;
        u32 fbr_chunksize;
        struct rx_ring *rx_ring = &adapter->rx_ring;
        struct fbr_lookup *fbr;

        /* Alloc memory for the lookup table */
        rx_ring->fbr[0] = kmalloc(sizeof(struct fbr_lookup), GFP_KERNEL);
        if (rx_ring->fbr[0] == NULL)
                return -ENOMEM;
        rx_ring->fbr[1] = kmalloc(sizeof(struct fbr_lookup), GFP_KERNEL);
        if (rx_ring->fbr[1] == NULL)
                return -ENOMEM;

        /* The first thing we will do is configure the sizes of the buffer
         * rings. These will change based on jumbo packet support.  Larger
         * jumbo packets increases the size of each entry in FBR0, and the
         * number of entries in FBR0, while at the same time decreasing the
         * number of entries in FBR1.
         *
         * FBR1 holds "large" frames, FBR0 holds "small" frames.  If FBR1
         * entries are huge in order to accommodate a "jumbo" frame, then it
         * will have less entries.  Conversely, FBR1 will now be relied upon
         * to carry more "normal" frames, thus it's entry size also increases
         * and the number of entries goes up too (since it now carries
         * "small" + "regular" packets.
         *
         * In this scheme, we try to maintain 512 entries between the two
         * rings. Also, FBR1 remains a constant size - when it's size doubles
         * the number of entries halves.  FBR0 increases in size, however.
         */

        if (adapter->registry_jumbo_packet < 2048) {
                rx_ring->fbr[0]->buffsize = 256;
                rx_ring->fbr[0]->num_entries = 512;
                rx_ring->fbr[1]->buffsize = 2048;
                rx_ring->fbr[1]->num_entries = 512;
        } else if (adapter->registry_jumbo_packet < 4096) {
                rx_ring->fbr[0]->buffsize = 512;
                rx_ring->fbr[0]->num_entries = 1024;
                rx_ring->fbr[1]->buffsize = 4096;
                rx_ring->fbr[1]->num_entries = 512;
        } else {
                rx_ring->fbr[0]->buffsize = 1024;
                rx_ring->fbr[0]->num_entries = 768;
                rx_ring->fbr[1]->buffsize = 16384;
                rx_ring->fbr[1]->num_entries = 128;
        }

        rx_ring->psr_num_entries = rx_ring->fbr[0]->num_entries +
                                   rx_ring->fbr[1]->num_entries;

        for (id = 0; id < NUM_FBRS; id++) {
                fbr = rx_ring->fbr[id];
                /* Allocate an area of memory for Free Buffer Ring */
                bufsize = sizeof(struct fbr_desc) * fbr->num_entries;
                fbr->ring_virtaddr = dma_alloc_coherent(&adapter->pdev->dev,
                                                        bufsize,
                                                        &fbr->ring_physaddr,
                                                        GFP_KERNEL);
                if (!fbr->ring_virtaddr) {
                        dev_err(&adapter->pdev->dev,
                           "Cannot alloc memory for Free Buffer Ring %d\n", id);
                        return -ENOMEM;
                }
        }

        for (id = 0; id < NUM_FBRS; id++) {
                fbr = rx_ring->fbr[id];
                fbr_chunksize = (FBR_CHUNKS * fbr->buffsize);

                for (i = 0; i < fbr->num_entries / FBR_CHUNKS; i++) {
                        dma_addr_t fbr_tmp_physaddr;

                        fbr->mem_virtaddrs[i] = dma_alloc_coherent(
                                        &adapter->pdev->dev, fbr_chunksize,
                                        &fbr->mem_physaddrs[i],
                                        GFP_KERNEL);

                        if (!fbr->mem_virtaddrs[i]) {
                                dev_err(&adapter->pdev->dev,
                                        "Could not alloc memory\n");
                                return -ENOMEM;
                        }

                        /* See NOTE in "Save Physical Address" comment above */
                        fbr_tmp_physaddr = fbr->mem_physaddrs[i];

                        for (j = 0; j < FBR_CHUNKS; j++) {
                                u32 index = (i * FBR_CHUNKS) + j;

                                /* Save the Virtual address of this index for
                                 * quick access later
                                 */
                                fbr->virt[index] = (u8 *)fbr->mem_virtaddrs[i] +
                                                   (j * fbr->buffsize);

                                /* now store the physical address in the
                                 * descriptor so the device can access it
                                 */
                                fbr->bus_high[index] =
                                                upper_32_bits(fbr_tmp_physaddr);
                                fbr->bus_low[index] =
                                                lower_32_bits(fbr_tmp_physaddr);

                                fbr_tmp_physaddr += fbr->buffsize;
                        }
                }
        }

        /* Allocate an area of memory for FIFO of Packet Status ring entries */
        pktstat_ringsize =
                sizeof(struct pkt_stat_desc) * rx_ring->psr_num_entries;

        rx_ring->ps_ring_virtaddr = dma_alloc_coherent(&adapter->pdev->dev,
                                                  pktstat_ringsize,
                                                  &rx_ring->ps_ring_physaddr,
                                                  GFP_KERNEL);

        if (!rx_ring->ps_ring_virtaddr) {
                dev_err(&adapter->pdev->dev,
                          "Cannot alloc memory for Packet Status Ring\n");
                return -ENOMEM;
        }

        /* NOTE : dma_alloc_coherent(), used above to alloc DMA regions,
         * ALWAYS returns SAC (32-bit) addresses. If DAC (64-bit) addresses
         * are ever returned, make sure the high part is retrieved here before
         * storing the adjusted address.
         */

        /* Allocate an area of memory for writeback of status information */
        rx_ring->rx_status_block = dma_alloc_coherent(&adapter->pdev->dev,
                                            sizeof(struct rx_status_block),
                                            &rx_ring->rx_status_bus,
                                            GFP_KERNEL);
        if (!rx_ring->rx_status_block) {
                dev_err(&adapter->pdev->dev,
                          "Cannot alloc memory for Status Block\n");
                return -ENOMEM;
        }
        rx_ring->num_rfd = NIC_DEFAULT_NUM_RFD;

        /* The RFDs are going to be put on lists later on, so initialize the
         * lists now.
         */
        INIT_LIST_HEAD(&rx_ring->recv_list);
        return 0;
}

/* et131x_rx_dma_memory_free - Free all memory allocated within this module */
static void et131x_rx_dma_memory_free(struct et131x_adapter *adapter)
{
        u8 id;
        u32 index;
        u32 bufsize;
        u32 pktstat_ringsize;
        struct rfd *rfd;
        struct rx_ring *rx_ring = &adapter->rx_ring;
        struct fbr_lookup *fbr;

        /* Free RFDs and associated packet descriptors */
        WARN_ON(rx_ring->num_ready_recv != rx_ring->num_rfd);

        while (!list_empty(&rx_ring->recv_list)) {
                rfd = list_entry(rx_ring->recv_list.next,
                                 struct rfd, list_node);

                list_del(&rfd->list_node);
                rfd->skb = NULL;
                kfree(rfd);
        }

        /* Free Free Buffer Rings */
        for (id = 0; id < NUM_FBRS; id++) {
                fbr = rx_ring->fbr[id];

                if (!fbr || !fbr->ring_virtaddr)
                        continue;

                /* First the packet memory */
                for (index = 0;
                     index < fbr->num_entries / FBR_CHUNKS;
                     index++) {
                        if (fbr->mem_virtaddrs[index]) {
                                bufsize = fbr->buffsize * FBR_CHUNKS;

                                dma_free_coherent(&adapter->pdev->dev,
                                                  bufsize,
                                                  fbr->mem_virtaddrs[index],
                                                  fbr->mem_physaddrs[index]);

                                fbr->mem_virtaddrs[index] = NULL;
                        }
                }

                bufsize = sizeof(struct fbr_desc) * fbr->num_entries;

                dma_free_coherent(&adapter->pdev->dev,
                                  bufsize,
                                  fbr->ring_virtaddr,
                                  fbr->ring_physaddr);

                fbr->ring_virtaddr = NULL;
        }

        /* Free Packet Status Ring */
        if (rx_ring->ps_ring_virtaddr) {
                pktstat_ringsize = sizeof(struct pkt_stat_desc) *
                                        rx_ring->psr_num_entries;

                dma_free_coherent(&adapter->pdev->dev, pktstat_ringsize,
                                    rx_ring->ps_ring_virtaddr,
                                    rx_ring->ps_ring_physaddr);

                rx_ring->ps_ring_virtaddr = NULL;
        }

        /* Free area of memory for the writeback of status information */
        if (rx_ring->rx_status_block) {
                dma_free_coherent(&adapter->pdev->dev,
                        sizeof(struct rx_status_block),
                        rx_ring->rx_status_block, rx_ring->rx_status_bus);
                rx_ring->rx_status_block = NULL;
        }

        /* Free the FBR Lookup Table */
        kfree(rx_ring->fbr[0]);
        kfree(rx_ring->fbr[1]);

        /* Reset Counters */
        rx_ring->num_ready_recv = 0;
}

/* et131x_init_recv - Initialize receive data structures */
static int et131x_init_recv(struct et131x_adapter *adapter)
{
        struct rfd *rfd;
        u32 rfdct;
        struct rx_ring *rx_ring = &adapter->rx_ring;

        /* Setup each RFD */
        for (rfdct = 0; rfdct < rx_ring->num_rfd; rfdct++) {
                rfd = kzalloc(sizeof(struct rfd), GFP_ATOMIC | GFP_DMA);
                if (!rfd)
                        return -ENOMEM;

                rfd->skb = NULL;

                /* Add this RFD to the recv_list */
                list_add_tail(&rfd->list_node, &rx_ring->recv_list);

                /* Increment the available RFD's */
                rx_ring->num_ready_recv++;
        }

        return 0;
}

/* et131x_set_rx_dma_timer - Set the heartbeat timer according to line rate */
static void et131x_set_rx_dma_timer(struct et131x_adapter *adapter)
{
        struct phy_device *phydev = adapter->phydev;

        /* For version B silicon, we do not use the RxDMA timer for 10 and 100
         * Mbits/s line rates. We do not enable and RxDMA interrupt coalescing.
         */
        if ((phydev->speed == SPEED_100) || (phydev->speed == SPEED_10)) {
                writel(0, &adapter->regs->rxdma.max_pkt_time);
                writel(1, &adapter->regs->rxdma.num_pkt_done);
        }
}

/* NICReturnRFD - Recycle a RFD and put it back onto the receive list
 * @adapter: pointer to our adapter
 * @rfd: pointer to the RFD
 */
static void nic_return_rfd(struct et131x_adapter *adapter, struct rfd *rfd)
{
        struct rx_ring *rx_local = &adapter->rx_ring;
        struct rxdma_regs __iomem *rx_dma = &adapter->regs->rxdma;
        u16 buff_index = rfd->bufferindex;
        u8 ring_index = rfd->ringindex;
        unsigned long flags;
        struct fbr_lookup *fbr = rx_local->fbr[ring_index];

        /* We don't use any of the OOB data besides status. Otherwise, we
         * need to clean up OOB data
         */
        if (buff_index < fbr->num_entries) {
                u32 free_buff_ring;
                u32 __iomem *offset;
                struct fbr_desc *next;

                spin_lock_irqsave(&adapter->fbr_lock, flags);

                if (ring_index == 0)
                        offset = &rx_dma->fbr0_full_offset;
                else
                        offset = &rx_dma->fbr1_full_offset;

                next = (struct fbr_desc *)(fbr->ring_virtaddr) +
                       INDEX10(fbr->local_full);

                /* Handle the Free Buffer Ring advancement here. Write
                 * the PA / Buffer Index for the returned buffer into
                 * the oldest (next to be freed)FBR entry
                 */
                next->addr_hi = fbr->bus_high[buff_index];
                next->addr_lo = fbr->bus_low[buff_index];
                next->word2 = buff_index;

                free_buff_ring = bump_free_buff_ring(&fbr->local_full,
                                                     fbr->num_entries - 1);
                writel(free_buff_ring, offset);

                spin_unlock_irqrestore(&adapter->fbr_lock, flags);
        } else {
                dev_err(&adapter->pdev->dev,
                          "%s illegal Buffer Index returned\n", __func__);
        }

        /* The processing on this RFD is done, so put it back on the tail of
         * our list
         */
        spin_lock_irqsave(&adapter->rcv_lock, flags);
        list_add_tail(&rfd->list_node, &rx_local->recv_list);
        rx_local->num_ready_recv++;
        spin_unlock_irqrestore(&adapter->rcv_lock, flags);

        WARN_ON(rx_local->num_ready_recv > rx_local->num_rfd);
}

/* nic_rx_pkts - Checks the hardware for available packets
 *
 * Returns rfd, a pointer to our MPRFD.
 *
 * Checks the hardware for available packets, using completion ring
 * If packets are available, it gets an RFD from the recv_list, attaches
 * the packet to it, puts the RFD in the RecvPendList, and also returns
 * the pointer to the RFD.
 */
static struct rfd *nic_rx_pkts(struct et131x_adapter *adapter)
{
        struct rx_ring *rx_local = &adapter->rx_ring;
        struct rx_status_block *status;
        struct pkt_stat_desc *psr;
        struct rfd *rfd;
        u32 i;
        u8 *buf;
        unsigned long flags;
        struct list_head *element;
        u8 ring_index;
        u16 buff_index;
        u32 len;
        u32 word0;
        u32 word1;
        struct sk_buff *skb;
        struct fbr_lookup *fbr;

        /* RX Status block is written by the DMA engine prior to every
         * interrupt. It contains the next to be used entry in the Packet
         * Status Ring, and also the two Free Buffer rings.
         */
        status = rx_local->rx_status_block;
        word1 = status->word1 >> 16;    /* Get the useful bits */

        /* Check the PSR and wrap bits do not match */
        if ((word1 & 0x1FFF) == (rx_local->local_psr_full & 0x1FFF))
                return NULL; /* Looks like this ring is not updated yet */

        /* The packet status ring indicates that data is available. */
        psr = (struct pkt_stat_desc *) (rx_local->ps_ring_virtaddr) +
                        (rx_local->local_psr_full & 0xFFF);

        /* Grab any information that is required once the PSR is advanced,
         * since we can no longer rely on the memory being accurate
         */
        len = psr->word1 & 0xFFFF;
        ring_index = (psr->word1 >> 26) & 0x03;
        fbr = rx_local->fbr[ring_index];
        buff_index = (psr->word1 >> 16) & 0x3FF;
        word0 = psr->word0;

        /* Indicate that we have used this PSR entry. */
        /* FIXME wrap 12 */
        add_12bit(&rx_local->local_psr_full, 1);
        if (
          (rx_local->local_psr_full & 0xFFF) > rx_local->psr_num_entries - 1) {
                /* Clear psr full and toggle the wrap bit */
                rx_local->local_psr_full &=  ~0xFFF;
                rx_local->local_psr_full ^= 0x1000;
        }

        writel(rx_local->local_psr_full, &adapter->regs->rxdma.psr_full_offset);

        if (ring_index > 1 || buff_index > fbr->num_entries - 1) {
                /* Illegal buffer or ring index cannot be used by S/W*/
                dev_err(&adapter->pdev->dev,
                        "NICRxPkts PSR Entry %d indicates length of %d and/or bad bi(%d)\n",
                        rx_local->local_psr_full & 0xFFF, len, buff_index);
                return NULL;
        }

        /* Get and fill the RFD. */
        spin_lock_irqsave(&adapter->rcv_lock, flags);

        element = rx_local->recv_list.next;
        rfd = list_entry(element, struct rfd, list_node);

        if (!rfd) {
                spin_unlock_irqrestore(&adapter->rcv_lock, flags);
                return NULL;
        }

        list_del(&rfd->list_node);
        rx_local->num_ready_recv--;

        spin_unlock_irqrestore(&adapter->rcv_lock, flags);

        rfd->bufferindex = buff_index;
        rfd->ringindex = ring_index;

        /* In V1 silicon, there is a bug which screws up filtering of runt
         * packets. Therefore runt packet filtering is disabled in the MAC and
         * the packets are dropped here. They are also counted here.
         */
        if (len < (NIC_MIN_PACKET_SIZE + 4)) {
                adapter->stats.rx_other_errs++;
                len = 0;
        }

        if (len == 0) {
                rfd->len = 0;
                goto out;
        }

        /* Determine if this is a multicast packet coming in */
        if ((word0 & ALCATEL_MULTICAST_PKT) &&
            !(word0 & ALCATEL_BROADCAST_PKT)) {
                /* Promiscuous mode and Multicast mode are not mutually
                 * exclusive as was first thought. I guess Promiscuous is just
                 * considered a super-set of the other filters. Generally filter
                 * is 0x2b when in promiscuous mode.
                 */
                if ((adapter->packet_filter & ET131X_PACKET_TYPE_MULTICAST)
                   && !(adapter->packet_filter & ET131X_PACKET_TYPE_PROMISCUOUS)
                   && !(adapter->packet_filter &
                                        ET131X_PACKET_TYPE_ALL_MULTICAST)) {
                        buf = fbr->virt[buff_index];

                        /* Loop through our list to see if the destination
                         * address of this packet matches one in our list.
                         */
                        for (i = 0; i < adapter->multicast_addr_count; i++) {
                                if (buf[0] == adapter->multicast_list[i][0]
                                 && buf[1] == adapter->multicast_list[i][1]
                                 && buf[2] == adapter->multicast_list[i][2]
                                 && buf[3] == adapter->multicast_list[i][3]
                                 && buf[4] == adapter->multicast_list[i][4]
                                 && buf[5] == adapter->multicast_list[i][5]) {
                                        break;
                                }
                        }

                        /* If our index is equal to the number of Multicast
                         * address we have, then this means we did not find this
                         * packet's matching address in our list. Set the len to
                         * zero, so we free our RFD when we return from this
                         * function.
                         */
                        if (i == adapter->multicast_addr_count)
                                len = 0;
                }

                if (len > 0)
                        adapter->stats.multicast_pkts_rcvd++;
        } else if (word0 & ALCATEL_BROADCAST_PKT) {
                adapter->stats.broadcast_pkts_rcvd++;
        } else {
                /* Not sure what this counter measures in promiscuous mode.
                 * Perhaps we should check the MAC address to see if it is
                 * directed to us in promiscuous mode.
                 */
                adapter->stats.unicast_pkts_rcvd++;
        }

        if (!len) {
                rfd->len = 0;
                goto out;
        }

        rfd->len = len;

        skb = dev_alloc_skb(rfd->len + 2);
        if (!skb) {
                dev_err(&adapter->pdev->dev, "Couldn't alloc an SKB for Rx\n");
                return NULL;
        }

        adapter->net_stats.rx_bytes += rfd->len;

        memcpy(skb_put(skb, rfd->len), fbr->virt[buff_index], rfd->len);

        skb->protocol = eth_type_trans(skb, adapter->netdev);
        skb->ip_summed = CHECKSUM_NONE;
        netif_rx_ni(skb);

out:
        nic_return_rfd(adapter, rfd);
        return rfd;
}

/* et131x_handle_recv_interrupt - Interrupt handler for receive processing
 *
 * Assumption, Rcv spinlock has been acquired.
 */
static void et131x_handle_recv_interrupt(struct et131x_adapter *adapter)
{
        struct rfd *rfd = NULL;
        u32 count = 0;
        bool done = true;
        struct rx_ring *rx_ring = &adapter->rx_ring;

        /* Process up to available RFD's */
        while (count < NUM_PACKETS_HANDLED) {
                if (list_empty(&rx_ring->recv_list)) {
                        WARN_ON(rx_ring->num_ready_recv != 0);
                        done = false;
                        break;
                }

                rfd = nic_rx_pkts(adapter);

                if (rfd == NULL)
                        break;

                /* Do not receive any packets until a filter has been set.
                 * Do not receive any packets until we have link.
                 * If length is zero, return the RFD in order to advance the
                 * Free buffer ring.
                 */
                if (!adapter->packet_filter ||
                    !netif_carrier_ok(adapter->netdev) ||
                    rfd->len == 0)
                        continue;

                /* Increment the number of packets we received */
                adapter->net_stats.rx_packets++;

                /* Set the status on the packet, either resources or success */
                if (rx_ring->num_ready_recv < RFD_LOW_WATER_MARK)
                        dev_warn(&adapter->pdev->dev, "RFD's are running out\n");

                count++;
        }

        if (count == NUM_PACKETS_HANDLED || !done) {
                rx_ring->unfinished_receives = true;
                writel(PARM_TX_TIME_INT_DEF * NANO_IN_A_MICRO,
                       &adapter->regs->global.watchdog_timer);
        } else
                /* Watchdog timer will disable itself if appropriate. */
                rx_ring->unfinished_receives = false;
}

/* et131x_tx_dma_memory_alloc
 *
 * Allocates memory that will be visible both to the device and to the CPU.
 * The OS will pass us packets, pointers to which we will insert in the Tx
 * Descriptor queue. The device will read this queue to find the packets in
 * memory. The device will update the "status" in memory each time it xmits a
 * packet.
 */
static int et131x_tx_dma_memory_alloc(struct et131x_adapter *adapter)
{
        int desc_size = 0;
        struct tx_ring *tx_ring = &adapter->tx_ring;

        /* Allocate memory for the TCB's (Transmit Control Block) */
        tx_ring->tcb_ring = kcalloc(NUM_TCB, sizeof(struct tcb),
                                    GFP_ATOMIC | GFP_DMA);
        if (!tx_ring->tcb_ring)
                return -ENOMEM;

        desc_size = (sizeof(struct tx_desc) * NUM_DESC_PER_RING_TX);
        tx_ring->tx_desc_ring = dma_alloc_coherent(&adapter->pdev->dev,
                                                   desc_size,
                                                   &tx_ring->tx_desc_ring_pa,
                                                   GFP_KERNEL);
        if (!tx_ring->tx_desc_ring) {
                dev_err(&adapter->pdev->dev,
                        "Cannot alloc memory for Tx Ring\n");
                return -ENOMEM;
        }

        /* Save physical address
         *
         * NOTE: dma_alloc_coherent(), used above to alloc DMA regions,
         * ALWAYS returns SAC (32-bit) addresses. If DAC (64-bit) addresses
         * are ever returned, make sure the high part is retrieved here before
         * storing the adjusted address.
         */
        /* Allocate memory for the Tx status block */
        tx_ring->tx_status = dma_alloc_coherent(&adapter->pdev->dev,
                                                    sizeof(u32),
                                                    &tx_ring->tx_status_pa,
                                                    GFP_KERNEL);
        if (!tx_ring->tx_status_pa) {
                dev_err(&adapter->pdev->dev,
                        "Cannot alloc memory for Tx status block\n");
                return -ENOMEM;
        }
        return 0;
}

/* et131x_tx_dma_memory_free - Free all memory allocated within this module */
static void et131x_tx_dma_memory_free(struct et131x_adapter *adapter)
{
        int desc_size = 0;
        struct tx_ring *tx_ring = &adapter->tx_ring;

        if (tx_ring->tx_desc_ring) {
                /* Free memory relating to Tx rings here */
                desc_size = (sizeof(struct tx_desc) * NUM_DESC_PER_RING_TX);
                dma_free_coherent(&adapter->pdev->dev,
                                  desc_size,
                                  tx_ring->tx_desc_ring,
                                  tx_ring->tx_desc_ring_pa);
                tx_ring->tx_desc_ring = NULL;
        }

        /* Free memory for the Tx status block */
        if (tx_ring->tx_status) {
                dma_free_coherent(&adapter->pdev->dev,
                                  sizeof(u32),
                                  tx_ring->tx_status,
                                  tx_ring->tx_status_pa);

                tx_ring->tx_status = NULL;
        }
        /* Free the memory for the tcb structures */
        kfree(tx_ring->tcb_ring);
}

/* nic_send_packet - NIC specific send handler for version B silicon.
 * @adapter: pointer to our adapter
 * @tcb: pointer to struct tcb
 */
static int nic_send_packet(struct et131x_adapter *adapter, struct tcb *tcb)
{
        u32 i;
        struct tx_desc desc[24];        /* 24 x 16 byte */
        u32 frag = 0;
        u32 thiscopy, remainder;
        struct sk_buff *skb = tcb->skb;
        u32 nr_frags = skb_shinfo(skb)->nr_frags + 1;
        struct skb_frag_struct *frags = &skb_shinfo(skb)->frags[0];
        unsigned long flags;
        struct phy_device *phydev = adapter->phydev;
        dma_addr_t dma_addr;
        struct tx_ring *tx_ring = &adapter->tx_ring;

        /* Part of the optimizations of this send routine restrict us to
         * sending 24 fragments at a pass.  In practice we should never see
         * more than 5 fragments.
         *
         * NOTE: The older version of this function (below) can handle any
         * number of fragments. If needed, we can call this function,
         * although it is less efficient.
         */

        /* nr_frags should be no more than 18. */
        BUILD_BUG_ON(MAX_SKB_FRAGS + 1 > 23);

        memset(desc, 0, sizeof(struct tx_desc) * (nr_frags + 1));

        for (i = 0; i < nr_frags; i++) {
                /* If there is something in this element, lets get a
                 * descriptor from the ring and get the necessary data
                 */
                if (i == 0) {
                        /* If the fragments are smaller than a standard MTU,
                         * then map them to a single descriptor in the Tx
                         * Desc ring. However, if they're larger, as is
                         * possible with support for jumbo packets, then
                         * split them each across 2 descriptors.
                         *
                         * This will work until we determine why the hardware
                         * doesn't seem to like large fragments.
                         */
                        if (skb_headlen(skb) <= 1514) {
                                /* Low 16bits are length, high is vlan and
                                 * unused currently so zero
                                 */
                                desc[frag].len_vlan = skb_headlen(skb);
                                dma_addr = dma_map_single(&adapter->pdev->dev,
                                                          skb->data,
                                                          skb_headlen(skb),
                                                          DMA_TO_DEVICE);
                                desc[frag].addr_lo = lower_32_bits(dma_addr);
                                desc[frag].addr_hi = upper_32_bits(dma_addr);
                                frag++;
                        } else {
                                desc[frag].len_vlan = skb_headlen(skb) / 2;
                                dma_addr = dma_map_single(&adapter->pdev->dev,
                                                         skb->data,
                                                         (skb_headlen(skb) / 2),
                                                         DMA_TO_DEVICE);
                                desc[frag].addr_lo = lower_32_bits(dma_addr);
                                desc[frag].addr_hi = upper_32_bits(dma_addr);
                                frag++;

                                desc[frag].len_vlan = skb_headlen(skb) / 2;
                                dma_addr = dma_map_single(&adapter->pdev->dev,
                                                         skb->data +
                                                         (skb_headlen(skb) / 2),
                                                         (skb_headlen(skb) / 2),
                                                         DMA_TO_DEVICE);
                                desc[frag].addr_lo = lower_32_bits(dma_addr);
                                desc[frag].addr_hi = upper_32_bits(dma_addr);
                                frag++;
                        }
                } else {
                        desc[frag].len_vlan = frags[i - 1].size;
                        dma_addr = skb_frag_dma_map(&adapter->pdev->dev,
                                                    &frags[i - 1],
                                                    0,
                                                    frags[i - 1].size,
                                                    DMA_TO_DEVICE);
                        desc[frag].addr_lo = lower_32_bits(dma_addr);
                        desc[frag].addr_hi = upper_32_bits(dma_addr);
                        frag++;
                }
        }

        if (phydev && phydev->speed == SPEED_1000) {
                if (++tx_ring->since_irq == PARM_TX_NUM_BUFS_DEF) {
                        /* Last element & Interrupt flag */
                        desc[frag - 1].flags =
                                    TXDESC_FLAG_INTPROC | TXDESC_FLAG_LASTPKT;
                        tx_ring->since_irq = 0;
                } else { /* Last element */
                        desc[frag - 1].flags = TXDESC_FLAG_LASTPKT;
                }
        } else
                desc[frag - 1].flags =
                                    TXDESC_FLAG_INTPROC | TXDESC_FLAG_LASTPKT;

        desc[0].flags |= TXDESC_FLAG_FIRSTPKT;

        tcb->index_start = tx_ring->send_idx;
        tcb->stale = 0;

        spin_lock_irqsave(&adapter->send_hw_lock, flags);

        thiscopy = NUM_DESC_PER_RING_TX - INDEX10(tx_ring->send_idx);

        if (thiscopy >= frag) {
                remainder = 0;
                thiscopy = frag;
        } else {
                remainder = frag - thiscopy;
        }

        memcpy(tx_ring->tx_desc_ring + INDEX10(tx_ring->send_idx),
               desc,
               sizeof(struct tx_desc) * thiscopy);

        add_10bit(&tx_ring->send_idx, thiscopy);

        if (INDEX10(tx_ring->send_idx) == 0 ||
                  INDEX10(tx_ring->send_idx) == NUM_DESC_PER_RING_TX) {
                tx_ring->send_idx &= ~ET_DMA10_MASK;
                tx_ring->send_idx ^= ET_DMA10_WRAP;
        }

        if (remainder) {
                memcpy(tx_ring->tx_desc_ring,
                       desc + thiscopy,
                       sizeof(struct tx_desc) * remainder);

                add_10bit(&tx_ring->send_idx, remainder);
        }

        if (INDEX10(tx_ring->send_idx) == 0) {
                if (tx_ring->send_idx)
                        tcb->index = NUM_DESC_PER_RING_TX - 1;
                else
                        tcb->index = ET_DMA10_WRAP|(NUM_DESC_PER_RING_TX - 1);
        } else
                tcb->index = tx_ring->send_idx - 1;

        spin_lock(&adapter->tcb_send_qlock);

        if (tx_ring->send_tail)
                tx_ring->send_tail->next = tcb;
        else
                tx_ring->send_head = tcb;

        tx_ring->send_tail = tcb;

        WARN_ON(tcb->next != NULL);

        tx_ring->used++;

        spin_unlock(&adapter->tcb_send_qlock);

        /* Write the new write pointer back to the device. */
        writel(tx_ring->send_idx, &adapter->regs->txdma.service_request);

        /* For Gig only, we use Tx Interrupt coalescing.  Enable the software
         * timer to wake us up if this packet isn't followed by N more.
         */
        if (phydev && phydev->speed == SPEED_1000) {
                writel(PARM_TX_TIME_INT_DEF * NANO_IN_A_MICRO,
                       &adapter->regs->global.watchdog_timer);
        }
        spin_unlock_irqrestore(&adapter->send_hw_lock, flags);

        return 0;
}

/* send_packet - Do the work to send a packet
 *
 * Assumption: Send spinlock has been acquired
 */
static int send_packet(struct sk_buff *skb, struct et131x_adapter *adapter)
{
        int status;
        struct tcb *tcb;
        u16 *shbufva;
        unsigned long flags;
        struct tx_ring *tx_ring = &adapter->tx_ring;

        /* All packets must have at least a MAC address and a protocol type */
        if (skb->len < ETH_HLEN)
                return -EIO;

        /* Get a TCB for this packet */
        spin_lock_irqsave(&adapter->tcb_ready_qlock, flags);

        tcb = tx_ring->tcb_qhead;

        if (tcb == NULL) {
                spin_unlock_irqrestore(&adapter->tcb_ready_qlock, flags);
                return -ENOMEM;
        }

        tx_ring->tcb_qhead = tcb->next;

        if (tx_ring->tcb_qhead == NULL)
                tx_ring->tcb_qtail = NULL;

        spin_unlock_irqrestore(&adapter->tcb_ready_qlock, flags);

        tcb->skb = skb;

        if (skb->data != NULL && skb_headlen(skb) >= 6) {
                shbufva = (u16 *) skb->data;

                if ((shbufva[0] == 0xffff) &&
                    (shbufva[1] == 0xffff) && (shbufva[2] == 0xffff))
                        tcb->flags |= FMP_DEST_BROAD;
                else if ((shbufva[0] & 0x3) == 0x0001)
                        tcb->flags |=  FMP_DEST_MULTI;
        }

        tcb->next = NULL;

        /* Call the NIC specific send handler. */
        status = nic_send_packet(adapter, tcb);

        if (status != 0) {
                spin_lock_irqsave(&adapter->tcb_ready_qlock, flags);

                if (tx_ring->tcb_qtail)
                        tx_ring->tcb_qtail->next = tcb;
                else
                        /* Apparently ready Q is empty. */

                        tx_ring->tcb_qhead = tcb;

                tx_ring->tcb_qtail = tcb;
                spin_unlock_irqrestore(&adapter->tcb_ready_qlock, flags);
                return status;
        }
        WARN_ON(tx_ring->used > NUM_TCB);
        return 0;
}

/* et131x_send_packets - This function is called by the OS to send packets */
static int et131x_send_packets(struct sk_buff *skb, struct net_device *netdev)
{
        int status = 0;
        struct et131x_adapter *adapter = netdev_priv(netdev);
        struct tx_ring *tx_ring = &adapter->tx_ring;

        /* Send these packets
         *
         * NOTE: The Linux Tx entry point is only given one packet at a time
         * to Tx, so the PacketCount and it's array used makes no sense here
         */

        /* TCB is not available */
        if (tx_ring->used >= NUM_TCB) {
                /* NOTE: If there's an error on send, no need to queue the
                 * packet under Linux; if we just send an error up to the
                 * netif layer, it will resend the skb to us.
                 */
                status = -ENOMEM;
        } else {
                /* We need to see if the link is up; if it's not, make the
                 * netif layer think we're good and drop the packet
                 */
                if ((adapter->flags & FMP_ADAPTER_FAIL_SEND_MASK) ||
                                        !netif_carrier_ok(netdev)) {
                        dev_kfree_skb_any(skb);
                        skb = NULL;

                        adapter->net_stats.tx_dropped++;
                } else {
                        status = send_packet(skb, adapter);
                        if (status != 0 && status != -ENOMEM) {
                                /* On any other error, make netif think we're
                                 * OK and drop the packet
                                 */
                                dev_kfree_skb_any(skb);
                                skb = NULL;
                                adapter->net_stats.tx_dropped++;
                        }
                }
        }
        return status;
}

/* free_send_packet - Recycle a struct tcb
 * @adapter: pointer to our adapter
 * @tcb: pointer to struct tcb
 *
 * Complete the packet if necessary
 * Assumption - Send spinlock has been acquired
 */
static inline void free_send_packet(struct et131x_adapter *adapter,
                                                struct tcb *tcb)
{
        unsigned long flags;
        struct tx_desc *desc = NULL;
        struct net_device_stats *stats = &adapter->net_stats;
        struct tx_ring *tx_ring = &adapter->tx_ring;
        u64  dma_addr;

        if (tcb->flags & FMP_DEST_BROAD)
                atomic_inc(&adapter->stats.broadcast_pkts_xmtd);
        else if (tcb->flags & FMP_DEST_MULTI)
                atomic_inc(&adapter->stats.multicast_pkts_xmtd);
        else
                atomic_inc(&adapter->stats.unicast_pkts_xmtd);

        if (tcb->skb) {
                stats->tx_bytes += tcb->skb->len;

                /* Iterate through the TX descriptors on the ring
                 * corresponding to this packet and umap the fragments
                 * they point to
                 */
                do {
                        desc = tx_ring->tx_desc_ring +
                               INDEX10(tcb->index_start);

                        dma_addr = desc->addr_lo;
                        dma_addr |= (u64)desc->addr_hi << 32;

                        dma_unmap_single(&adapter->pdev->dev,
                                         dma_addr,
                                         desc->len_vlan, DMA_TO_DEVICE);

                        add_10bit(&tcb->index_start, 1);
                        if (INDEX10(tcb->index_start) >=
                                                        NUM_DESC_PER_RING_TX) {
                                tcb->index_start &= ~ET_DMA10_MASK;
                                tcb->index_start ^= ET_DMA10_WRAP;
                        }
                } while (desc != tx_ring->tx_desc_ring + INDEX10(tcb->index));

                dev_kfree_skb_any(tcb->skb);
        }

        memset(tcb, 0, sizeof(struct tcb));

        /* Add the TCB to the Ready Q */
        spin_lock_irqsave(&adapter->tcb_ready_qlock, flags);

        adapter->net_stats.tx_packets++;

        if (tx_ring->tcb_qtail)
                tx_ring->tcb_qtail->next = tcb;
        else
                /* Apparently ready Q is empty. */
                tx_ring->tcb_qhead = tcb;

        tx_ring->tcb_qtail = tcb;

        spin_unlock_irqrestore(&adapter->tcb_ready_qlock, flags);
        WARN_ON(tx_ring->used < 0);
}

/* et131x_free_busy_send_packets - Free and complete the stopped active sends
 *
 * Assumption - Send spinlock has been acquired
 */
static void et131x_free_busy_send_packets(struct et131x_adapter *adapter)
{
        struct tcb *tcb;
        unsigned long flags;
        u32 freed = 0;
        struct tx_ring *tx_ring = &adapter->tx_ring;

        /* Any packets being sent? Check the first TCB on the send list */
        spin_lock_irqsave(&adapter->tcb_send_qlock, flags);

        tcb = tx_ring->send_head;

        while (tcb != NULL && freed < NUM_TCB) {
                struct tcb *next = tcb->next;

                tx_ring->send_head = next;

                if (next == NULL)
                        tx_ring->send_tail = NULL;

                tx_ring->used--;

                spin_unlock_irqrestore(&adapter->tcb_send_qlock, flags);

                freed++;
                free_send_packet(adapter, tcb);

                spin_lock_irqsave(&adapter->tcb_send_qlock, flags);

                tcb = tx_ring->send_head;
        }

        WARN_ON(freed == NUM_TCB);

        spin_unlock_irqrestore(&adapter->tcb_send_qlock, flags);

        tx_ring->used = 0;
}

/* et131x_handle_send_interrupt - Interrupt handler for sending processing
 *
 * Re-claim the send resources, complete sends and get more to send from
 * the send wait queue.
 *
 * Assumption - Send spinlock has been acquired
 */
static void et131x_handle_send_interrupt(struct et131x_adapter *adapter)
{
        unsigned long flags;
        u32 serviced;
        struct tcb *tcb;
        u32 index;
        struct tx_ring *tx_ring = &adapter->tx_ring;

        serviced = readl(&adapter->regs->txdma.new_service_complete);
        index = INDEX10(serviced);

        /* Has the ring wrapped?  Process any descriptors that do not have
         * the same "wrap" indicator as the current completion indicator
         */
        spin_lock_irqsave(&adapter->tcb_send_qlock, flags);

        tcb = tx_ring->send_head;

        while (tcb &&
               ((serviced ^ tcb->index) & ET_DMA10_WRAP) &&
               index < INDEX10(tcb->index)) {
                tx_ring->used--;
                tx_ring->send_head = tcb->next;
                if (tcb->next == NULL)
                        tx_ring->send_tail = NULL;

                spin_unlock_irqrestore(&adapter->tcb_send_qlock, flags);
                free_send_packet(adapter, tcb);
                spin_lock_irqsave(&adapter->tcb_send_qlock, flags);

                /* Goto the next packet */
                tcb = tx_ring->send_head;
        }
        while (tcb &&
               !((serviced ^ tcb->index) & ET_DMA10_WRAP)
               && index > (tcb->index & ET_DMA10_MASK)) {
                tx_ring->used--;
                tx_ring->send_head = tcb->next;
                if (tcb->next == NULL)
                        tx_ring->send_tail = NULL;

                spin_unlock_irqrestore(&adapter->tcb_send_qlock, flags);
                free_send_packet(adapter, tcb);
                spin_lock_irqsave(&adapter->tcb_send_qlock, flags);

                /* Goto the next packet */
                tcb = tx_ring->send_head;
        }

        /* Wake up the queue when we hit a low-water mark */
        if (tx_ring->used <= NUM_TCB / 3)
                netif_wake_queue(adapter->netdev);

        spin_unlock_irqrestore(&adapter->tcb_send_qlock, flags);
}

static int et131x_get_settings(struct net_device *netdev,
                               struct ethtool_cmd *cmd)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);

        return phy_ethtool_gset(adapter->phydev, cmd);
}

static int et131x_set_settings(struct net_device *netdev,
                               struct ethtool_cmd *cmd)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);

        return phy_ethtool_sset(adapter->phydev, cmd);
}

static int et131x_get_regs_len(struct net_device *netdev)
{
#define ET131X_REGS_LEN 256
        return ET131X_REGS_LEN * sizeof(u32);
}

static void et131x_get_regs(struct net_device *netdev,
                            struct ethtool_regs *regs, void *regs_data)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);
        struct address_map __iomem *aregs = adapter->regs;
        u32 *regs_buff = regs_data;
        u32 num = 0;
        u16 tmp;

        memset(regs_data, 0, et131x_get_regs_len(netdev));

        regs->version = (1 << 24) | (adapter->pdev->revision << 16) |
                        adapter->pdev->device;

        /* PHY regs */
        et131x_mii_read(adapter, MII_BMCR, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_BMSR, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_PHYSID1, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_PHYSID2, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_ADVERTISE, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_LPA, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_EXPANSION, &tmp);
        regs_buff[num++] = tmp;
        /* Autoneg next page transmit reg */
        et131x_mii_read(adapter, 0x07, &tmp);
        regs_buff[num++] = tmp;
        /* Link partner next page reg */
        et131x_mii_read(adapter, 0x08, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_CTRL1000, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_STAT1000, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, 0x0b, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, 0x0c, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_MMD_CTRL, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_MMD_DATA, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, MII_ESTATUS, &tmp);
        regs_buff[num++] = tmp;

        et131x_mii_read(adapter, PHY_INDEX_REG, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_DATA_REG, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_MPHY_CONTROL_REG, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_LOOPBACK_CONTROL, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_LOOPBACK_CONTROL + 1, &tmp);
        regs_buff[num++] = tmp;

        et131x_mii_read(adapter, PHY_REGISTER_MGMT_CONTROL, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_CONFIG, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_PHY_CONTROL, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_INTERRUPT_MASK, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_INTERRUPT_STATUS, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_PHY_STATUS, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_LED_1, &tmp);
        regs_buff[num++] = tmp;
        et131x_mii_read(adapter, PHY_LED_2, &tmp);
        regs_buff[num++] = tmp;

        /* Global regs */
        regs_buff[num++] = readl(&aregs->global.txq_start_addr);
        regs_buff[num++] = readl(&aregs->global.txq_end_addr);
        regs_buff[num++] = readl(&aregs->global.rxq_start_addr);
        regs_buff[num++] = readl(&aregs->global.rxq_end_addr);
        regs_buff[num++] = readl(&aregs->global.pm_csr);
        regs_buff[num++] = adapter->stats.interrupt_status;
        regs_buff[num++] = readl(&aregs->global.int_mask);
        regs_buff[num++] = readl(&aregs->global.int_alias_clr_en);
        regs_buff[num++] = readl(&aregs->global.int_status_alias);
        regs_buff[num++] = readl(&aregs->global.sw_reset);
        regs_buff[num++] = readl(&aregs->global.slv_timer);
        regs_buff[num++] = readl(&aregs->global.msi_config);
        regs_buff[num++] = readl(&aregs->global.loopback);
        regs_buff[num++] = readl(&aregs->global.watchdog_timer);

        /* TXDMA regs */
        regs_buff[num++] = readl(&aregs->txdma.csr);
        regs_buff[num++] = readl(&aregs->txdma.pr_base_hi);
        regs_buff[num++] = readl(&aregs->txdma.pr_base_lo);
        regs_buff[num++] = readl(&aregs->txdma.pr_num_des);
        regs_buff[num++] = readl(&aregs->txdma.txq_wr_addr);
        regs_buff[num++] = readl(&aregs->txdma.txq_wr_addr_ext);
        regs_buff[num++] = readl(&aregs->txdma.txq_rd_addr);
        regs_buff[num++] = readl(&aregs->txdma.dma_wb_base_hi);
        regs_buff[num++] = readl(&aregs->txdma.dma_wb_base_lo);
        regs_buff[num++] = readl(&aregs->txdma.service_request);
        regs_buff[num++] = readl(&aregs->txdma.service_complete);
        regs_buff[num++] = readl(&aregs->txdma.cache_rd_index);
        regs_buff[num++] = readl(&aregs->txdma.cache_wr_index);
        regs_buff[num++] = readl(&aregs->txdma.tx_dma_error);
        regs_buff[num++] = readl(&aregs->txdma.desc_abort_cnt);
        regs_buff[num++] = readl(&aregs->txdma.payload_abort_cnt);
        regs_buff[num++] = readl(&aregs->txdma.writeback_abort_cnt);
        regs_buff[num++] = readl(&aregs->txdma.desc_timeout_cnt);
        regs_buff[num++] = readl(&aregs->txdma.payload_timeout_cnt);
        regs_buff[num++] = readl(&aregs->txdma.writeback_timeout_cnt);
        regs_buff[num++] = readl(&aregs->txdma.desc_error_cnt);
        regs_buff[num++] = readl(&aregs->txdma.payload_error_cnt);
        regs_buff[num++] = readl(&aregs->txdma.writeback_error_cnt);
        regs_buff[num++] = readl(&aregs->txdma.dropped_tlp_cnt);
        regs_buff[num++] = readl(&aregs->txdma.new_service_complete);
        regs_buff[num++] = readl(&aregs->txdma.ethernet_packet_cnt);

        /* RXDMA regs */
        regs_buff[num++] = readl(&aregs->rxdma.csr);
        regs_buff[num++] = readl(&aregs->rxdma.dma_wb_base_hi);
        regs_buff[num++] = readl(&aregs->rxdma.dma_wb_base_lo);
        regs_buff[num++] = readl(&aregs->rxdma.num_pkt_done);
        regs_buff[num++] = readl(&aregs->rxdma.max_pkt_time);
        regs_buff[num++] = readl(&aregs->rxdma.rxq_rd_addr);
        regs_buff[num++] = readl(&aregs->rxdma.rxq_rd_addr_ext);
        regs_buff[num++] = readl(&aregs->rxdma.rxq_wr_addr);
        regs_buff[num++] = readl(&aregs->rxdma.psr_base_hi);
        regs_buff[num++] = readl(&aregs->rxdma.psr_base_lo);
        regs_buff[num++] = readl(&aregs->rxdma.psr_num_des);
        regs_buff[num++] = readl(&aregs->rxdma.psr_avail_offset);
        regs_buff[num++] = readl(&aregs->rxdma.psr_full_offset);
        regs_buff[num++] = readl(&aregs->rxdma.psr_access_index);
        regs_buff[num++] = readl(&aregs->rxdma.psr_min_des);
        regs_buff[num++] = readl(&aregs->rxdma.fbr0_base_lo);
        regs_buff[num++] = readl(&aregs->rxdma.fbr0_base_hi);
        regs_buff[num++] = readl(&aregs->rxdma.fbr0_num_des);
        regs_buff[num++] = readl(&aregs->rxdma.fbr0_avail_offset);
        regs_buff[num++] = readl(&aregs->rxdma.fbr0_full_offset);
        regs_buff[num++] = readl(&aregs->rxdma.fbr0_rd_index);
        regs_buff[num++] = readl(&aregs->rxdma.fbr0_min_des);
        regs_buff[num++] = readl(&aregs->rxdma.fbr1_base_lo);
        regs_buff[num++] = readl(&aregs->rxdma.fbr1_base_hi);
        regs_buff[num++] = readl(&aregs->rxdma.fbr1_num_des);
        regs_buff[num++] = readl(&aregs->rxdma.fbr1_avail_offset);
        regs_buff[num++] = readl(&aregs->rxdma.fbr1_full_offset);
        regs_buff[num++] = readl(&aregs->rxdma.fbr1_rd_index);
        regs_buff[num++] = readl(&aregs->rxdma.fbr1_min_des);
}

static void et131x_get_drvinfo(struct net_device *netdev,
                               struct ethtool_drvinfo *info)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);

        strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
        strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
        strlcpy(info->bus_info, pci_name(adapter->pdev),
                sizeof(info->bus_info));
}

static struct ethtool_ops et131x_ethtool_ops = {
        .get_settings   = et131x_get_settings,
        .set_settings   = et131x_set_settings,
        .get_drvinfo    = et131x_get_drvinfo,
        .get_regs_len   = et131x_get_regs_len,
        .get_regs       = et131x_get_regs,
        .get_link       = ethtool_op_get_link,
};

/* et131x_hwaddr_init - set up the MAC Address on the ET1310 */
static void et131x_hwaddr_init(struct et131x_adapter *adapter)
{
        /* If have our default mac from init and no mac address from
         * EEPROM then we need to generate the last octet and set it on the
         * device
         */
        if (is_zero_ether_addr(adapter->rom_addr)) {
                /* We need to randomly generate the last octet so we
                 * decrease our chances of setting the mac address to
                 * same as another one of our cards in the system
                 */
                get_random_bytes(&adapter->addr[5], 1);
                /* We have the default value in the register we are
                 * working with so we need to copy the current
                 * address into the permanent address
                 */
                memcpy(adapter->rom_addr,
                        adapter->addr, ETH_ALEN);
        } else {
                /* We do not have an override address, so set the
                 * current address to the permanent address and add
                 * it to the device
                 */
                memcpy(adapter->addr,
                       adapter->rom_addr, ETH_ALEN);
        }
}

/* et131x_pci_init       - initial PCI setup
 *
 * Perform the initial setup of PCI registers and if possible initialise
 * the MAC address. At this point the I/O registers have yet to be mapped
 */
static int et131x_pci_init(struct et131x_adapter *adapter,
                           struct pci_dev *pdev)
{
        u16 max_payload;
        int i, rc;

        rc = et131x_init_eeprom(adapter);
        if (rc < 0)
                goto out;

        if (!pci_is_pcie(pdev)) {
                dev_err(&pdev->dev, "Missing PCIe capabilities\n");
                goto err_out;
        }

        /* Let's set up the PORT LOGIC Register. */

        /* Program the Ack/Nak latency and replay timers */
        max_payload = pdev->pcie_mpss;

        if (max_payload < 2) {
                static const u16 acknak[2] = { 0x76, 0xD0 };
                static const u16 replay[2] = { 0x1E0, 0x2ED };

                if (pci_write_config_word(pdev, ET1310_PCI_ACK_NACK,
                                               acknak[max_payload])) {
                        dev_err(&pdev->dev,
                          "Could not write PCI config space for ACK/NAK\n");
                        goto err_out;
                }
                if (pci_write_config_word(pdev, ET1310_PCI_REPLAY,
                                               replay[max_payload])) {
                        dev_err(&pdev->dev,
                          "Could not write PCI config space for Replay Timer\n");
                        goto err_out;
                }
        }

        /* l0s and l1 latency timers.  We are using default values.
         * Representing 001 for L0s and 010 for L1
         */
        if (pci_write_config_byte(pdev, ET1310_PCI_L0L1LATENCY, 0x11)) {
                dev_err(&pdev->dev,
                  "Could not write PCI config space for Latency Timers\n");
                goto err_out;
        }

        /* Change the max read size to 2k */
        if (pcie_set_readrq(pdev, 2048)) {
                dev_err(&pdev->dev,
                        "Couldn't change PCI config space for Max read size\n");
                goto err_out;
        }

        /* Get MAC address from config space if an eeprom exists, otherwise
         * the MAC address there will not be valid
         */
        if (!adapter->has_eeprom) {
                et131x_hwaddr_init(adapter);
                return 0;
        }

        for (i = 0; i < ETH_ALEN; i++) {
                if (pci_read_config_byte(pdev, ET1310_PCI_MAC_ADDRESS + i,
                                        adapter->rom_addr + i)) {
                        dev_err(&pdev->dev, "Could not read PCI config space for MAC address\n");
                        goto err_out;
                }
        }
        ether_addr_copy(adapter->addr, adapter->rom_addr);
out:
        return rc;
err_out:
        rc = -EIO;
        goto out;
}

/* et131x_error_timer_handler
 * @data: timer-specific variable; here a pointer to our adapter structure
 *
 * The routine called when the error timer expires, to track the number of
 * recurring errors.
 */
static void et131x_error_timer_handler(unsigned long data)
{
        struct et131x_adapter *adapter = (struct et131x_adapter *) data;
        struct phy_device *phydev = adapter->phydev;

        if (et1310_in_phy_coma(adapter)) {
                /* Bring the device immediately out of coma, to
                 * prevent it from sleeping indefinitely, this
                 * mechanism could be improved!
                 */
                et1310_disable_phy_coma(adapter);
                adapter->boot_coma = 20;
        } else {
                et1310_update_macstat_host_counters(adapter);
        }

        if (!phydev->link && adapter->boot_coma < 11)
                adapter->boot_coma++;

        if (adapter->boot_coma == 10) {
                if (!phydev->link) {
                        if (!et1310_in_phy_coma(adapter)) {
                                /* NOTE - This was originally a 'sync with
                                 *  interrupt'. How to do that under Linux?
                                 */
                                et131x_enable_interrupts(adapter);
                                et1310_enable_phy_coma(adapter);
                        }
                }
        }

        /* This is a periodic timer, so reschedule */
        mod_timer(&adapter->error_timer, jiffies + TX_ERROR_PERIOD * HZ / 1000);
}

/* et131x_adapter_memory_free - Free all memory allocated for use by Tx & Rx */
static void et131x_adapter_memory_free(struct et131x_adapter *adapter)
{
        et131x_tx_dma_memory_free(adapter);
        et131x_rx_dma_memory_free(adapter);
}

/* et131x_adapter_memory_alloc
 * Allocate all the memory blocks for send, receive and others.
 */
static int et131x_adapter_memory_alloc(struct et131x_adapter *adapter)
{
        int status;

        /* Allocate memory for the Tx Ring */
        status = et131x_tx_dma_memory_alloc(adapter);
        if (status) {
                dev_err(&adapter->pdev->dev,
                          "et131x_tx_dma_memory_alloc FAILED\n");
                et131x_tx_dma_memory_free(adapter);
                return status;
        }
        /* Receive buffer memory allocation */
        status = et131x_rx_dma_memory_alloc(adapter);
        if (status) {
                dev_err(&adapter->pdev->dev,
                          "et131x_rx_dma_memory_alloc FAILED\n");
                et131x_adapter_memory_free(adapter);
                return status;
        }

        /* Init receive data structures */
        status = et131x_init_recv(adapter);
        if (status) {
                dev_err(&adapter->pdev->dev, "et131x_init_recv FAILED\n");
                et131x_adapter_memory_free(adapter);
        }
        return status;
}

static void et131x_adjust_link(struct net_device *netdev)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);
        struct  phy_device *phydev = adapter->phydev;

        if (!phydev)
                return;
        if (phydev->link == adapter->link)
                return;

        /* Check to see if we are in coma mode and if
         * so, disable it because we will not be able
         * to read PHY values until we are out.
         */
        if (et1310_in_phy_coma(adapter))
                et1310_disable_phy_coma(adapter);

        adapter->link = phydev->link;
        phy_print_status(phydev);

        if (phydev->link) {
                adapter->boot_coma = 20;
                if (phydev->speed == SPEED_10) {
                        u16 register18;

                        et131x_mii_read(adapter, PHY_MPHY_CONTROL_REG,
                                         &register18);
                        et131x_mii_write(adapter, PHY_MPHY_CONTROL_REG,
                                         register18 | 0x4);
                        et131x_mii_write(adapter, PHY_INDEX_REG,
                                         register18 | 0x8402);
                        et131x_mii_write(adapter, PHY_DATA_REG,
                                         register18 | 511);
                        et131x_mii_write(adapter, PHY_MPHY_CONTROL_REG,
                                         register18);
                }

                et1310_config_flow_control(adapter);

                if (phydev->speed == SPEED_1000 &&
                    adapter->registry_jumbo_packet > 2048) {
                        u16 reg;

                        et131x_mii_read(adapter, PHY_CONFIG, &reg);
                        reg &= ~ET_PHY_CONFIG_TX_FIFO_DEPTH;
                        reg |= ET_PHY_CONFIG_FIFO_DEPTH_32;
                        et131x_mii_write(adapter, PHY_CONFIG, reg);
                }

                et131x_set_rx_dma_timer(adapter);
                et1310_config_mac_regs2(adapter);
        } else {
                adapter->boot_coma = 0;

                if (phydev->speed == SPEED_10) {
                        u16 register18;

                        et131x_mii_read(adapter, PHY_MPHY_CONTROL_REG,
                                         &register18);
                        et131x_mii_write(adapter, PHY_MPHY_CONTROL_REG,
                                         register18 | 0x4);
                        et131x_mii_write(adapter, PHY_INDEX_REG,
                                         register18 | 0x8402);
                        et131x_mii_write(adapter, PHY_DATA_REG,
                                         register18 | 511);
                        et131x_mii_write(adapter, PHY_MPHY_CONTROL_REG,
                                         register18);
                }

                /* Free the packets being actively sent & stopped */
                et131x_free_busy_send_packets(adapter);

                /* Re-initialize the send structures */
                et131x_init_send(adapter);

                /* Bring the device back to the state it was during
                 * init prior to autonegotiation being complete. This
                 * way, when we get the auto-neg complete interrupt,
                 * we can complete init by calling config_mac_regs2.
                 */
                et131x_soft_reset(adapter);

                /* Setup ET1310 as per the documentation */
                et131x_adapter_setup(adapter);

                /* perform reset of tx/rx */
                et131x_disable_txrx(netdev);
                et131x_enable_txrx(netdev);
        }
}

static int et131x_mii_probe(struct net_device *netdev)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);
        struct  phy_device *phydev = NULL;

        phydev = phy_find_first(adapter->mii_bus);
        if (!phydev) {
                dev_err(&adapter->pdev->dev, "no PHY found\n");
                return -ENODEV;
        }

        phydev = phy_connect(netdev, dev_name(&phydev->dev),
                             &et131x_adjust_link, PHY_INTERFACE_MODE_MII);

        if (IS_ERR(phydev)) {
                dev_err(&adapter->pdev->dev, "Could not attach to PHY\n");
                return PTR_ERR(phydev);
        }

        phydev->supported &= (SUPPORTED_10baseT_Half
                                | SUPPORTED_10baseT_Full
                                | SUPPORTED_100baseT_Half
                                | SUPPORTED_100baseT_Full
                                | SUPPORTED_Autoneg
                                | SUPPORTED_MII
                                | SUPPORTED_TP);

        if (adapter->pdev->device != ET131X_PCI_DEVICE_ID_FAST)
                phydev->supported |= SUPPORTED_1000baseT_Full;

        phydev->advertising = phydev->supported;
        adapter->phydev = phydev;

        dev_info(&adapter->pdev->dev,
                 "attached PHY driver [%s] (mii_bus:phy_addr=%s)\n",
                 phydev->drv->name, dev_name(&phydev->dev));

        return 0;
}

/* et131x_adapter_init
 *
 * Initialize the data structures for the et131x_adapter object and link
 * them together with the platform provided device structures.
 */
static struct et131x_adapter *et131x_adapter_init(struct net_device *netdev,
                                                  struct pci_dev *pdev)
{
        static const u8 default_mac[] = { 0x00, 0x05, 0x3d, 0x00, 0x02, 0x00 };

        struct et131x_adapter *adapter;

        /* Allocate private adapter struct and copy in relevant information */
        adapter = netdev_priv(netdev);
        adapter->pdev = pci_dev_get(pdev);
        adapter->netdev = netdev;

        /* Initialize spinlocks here */
        spin_lock_init(&adapter->tcb_send_qlock);
        spin_lock_init(&adapter->tcb_ready_qlock);
        spin_lock_init(&adapter->send_hw_lock);
        spin_lock_init(&adapter->rcv_lock);
        spin_lock_init(&adapter->fbr_lock);

        adapter->registry_jumbo_packet = 1514;  /* 1514-9216 */

        /* Set the MAC address to a default */
        ether_addr_copy(adapter->addr, default_mac);

        return adapter;
}

/* et131x_pci_remove
 *
 * Registered in the pci_driver structure, this function is called when the
 * PCI subsystem detects that a PCI device which matches the information
 * contained in the pci_device_id table has been removed.
 */
static void et131x_pci_remove(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct et131x_adapter *adapter = netdev_priv(netdev);

        unregister_netdev(netdev);
        phy_disconnect(adapter->phydev);
        mdiobus_unregister(adapter->mii_bus);
        cancel_work_sync(&adapter->task);
        kfree(adapter->mii_bus->irq);
        mdiobus_free(adapter->mii_bus);

        et131x_adapter_memory_free(adapter);
        iounmap(adapter->regs);
        pci_dev_put(pdev);

        free_netdev(netdev);
        pci_release_regions(pdev);
        pci_disable_device(pdev);
}

/* et131x_up - Bring up a device for use.  */
static void et131x_up(struct net_device *netdev)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);

        et131x_enable_txrx(netdev);
        phy_start(adapter->phydev);
}

/* et131x_down - Bring down the device */
static void et131x_down(struct net_device *netdev)
{
        struct et131x_adapter *adapter = netdev_priv(netdev);

        /* Save the timestamp for the TX watchdog, prevent a timeout */
        netdev->trans_start = jiffies;

        phy_stop(adapter->phydev);
        et131x_disable_txrx(netdev);
}

#ifdef CONFIG_PM_SLEEP
static int et131x_suspend(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct net_device *netdev = pci_get_drvdata(pdev);

        if (netif_running(netdev)) {
                netif_device_detach(netdev);
                et131x_down(netdev);
                pci_save_state(pdev);
        }

        return 0;
}

static int et131x_resume(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct net_device *netdev = pci_get_drvdata(pdev);

        if (netif_running(netdev)) {
                pci_restore_state(pdev);
                et131x_up(netdev);
                netif_device_attach(netdev);
        }

        return 0;
}

static SIMPLE_DEV_PM_OPS(et131x_pm_ops, et131x_suspend, et131x_resume);
#define ET131X_PM_OPS (&et131x_pm_ops)
#else
#define ET131X_PM_OPS NULL
#endif

/* et131x_isr - The Interrupt Service Routine for the driver.
 * @irq: the IRQ on which the interrupt was received.
 * @dev_id: device-specific info (here a pointer to a net_device struct)
 *
 * Returns a value indicating if the interrupt was handled.
 */
static irqreturn_t et131x_isr(int irq, void *dev_id)
{
        bool handled = true;
        struct net_device *netdev = (struct net_device *)dev_id;
        struct et131x_adapter *adapter = netdev_priv(netdev);
        struct rx_ring *rx_ring = &adapter->rx_ring;
        struct tx_ring *tx_ring = &adapter->tx_ring;
        u32 status;

        if (!netif_device_present(netdev)) {
                handled = false;
                goto out;
        }

        /* If the adapter is in low power state, then it should not
         * recognize any interrupt
         */

        /* Disable Device Interrupts */
        et131x_disable_interrupts(adapter);

        /* Get a copy of the value in the interrupt status register
         * so we can process the interrupting section
         */
        status = readl(&adapter->regs->global.int_status);

        if (adapter->flowcontrol == FLOW_TXONLY ||
            adapter->flowcontrol == FLOW_BOTH) {
                status &= ~INT_MASK_ENABLE;
        } else {
                status &= ~INT_MASK_ENABLE_NO_FLOW;
        }

        /* Make sure this is our interrupt */
        if (!status) {
                handled = false;
                et131x_enable_interrupts(adapter);
                goto out;
        }

        /* This is our interrupt, so process accordingly */

        if (status & ET_INTR_WATCHDOG) {
                struct tcb *tcb = tx_ring->send_head;

                if (tcb)
                        if (++tcb->stale > 1)
                                status |= ET_INTR_TXDMA_ISR;

                if (rx_ring->unfinished_receives)
                        status |= ET_INTR_RXDMA_XFR_DONE;
                else if (tcb == NULL)
                        writel(0, &adapter->regs->global.watchdog_timer);

                status &= ~ET_INTR_WATCHDOG;
        }

        if (!status) {
                /* This interrupt has in some way been "handled" by
                 * the ISR. Either it was a spurious Rx interrupt, or
                 * it was a Tx interrupt that has been filtered by
                 * the ISR.
                 */
                et131x_enable_interrupts(adapter);
                goto out;
        }

        /* We need to save the interrupt status value for use in our
         * DPC. We will clear the software copy of that in that
         * routine.
         */
        adapter->stats.interrupt_status = status;

        /* Schedule the ISR handler as a bottom-half task in the
         * kernel's tq_immediate queue, and mark the queue for
         * execution
         */
        schedule_work(&adapter->task);
out:
        return IRQ_RETVAL(handled);
}

/* et131x_isr_handler - The ISR handler
 *
 * scheduled to run in a deferred context by the ISR. This is where the ISR's
 * work actually gets done.
 */
static void et131x_isr_handler(struct work_struct *work)
{
        struct et131x_adapter *adapter =
                container_of(work, struct et131x_adapter, task);
        u32 status = adapter->stats.interrupt_status;
        struct address_map __iomem *iomem = adapter->regs;

        /* These first two are by far the most common.  Once handled, we clear
         * their two bits in the status word.  If the word is now zero, we
         * exit.
         */
        /* Handle all the completed Transmit interrupts */
        if (status & ET_INTR_TXDMA_ISR)
                et131x_handle_send_interrupt(adapter);

        /* Handle all the completed Receives interrupts */
        if (status & ET_INTR_RXDMA_XFR_DONE)
                et131x_handle_recv_interrupt(adapter);

        status &= ~(ET_INTR_TXDMA_ERR | ET_INTR_RXDMA_XFR_DONE);

        if (!status)
                goto out;

        /* Handle the TXDMA Error interrupt */
        if (status & ET_INTR_TXDMA_ERR) {
                /* Following read also clears the register (COR) */
                u32 txdma_err = readl(&iomem->txdma.tx_dma_error);

                dev_warn(&adapter->pdev->dev,
                            "TXDMA_ERR interrupt, error = %d\n",
                            txdma_err);
        }

        /* Handle Free Buffer Ring 0 and 1 Low interrupt */
        if (status & (ET_INTR_RXDMA_FB_R0_LOW | ET_INTR_RXDMA_FB_R1_LOW)) {
                /* This indicates the number of unused buffers in RXDMA free
                 * buffer ring 0 is <= the limit you programmed. Free buffer
                 * resources need to be returned.  Free buffers are consumed as
                 * packets are passed from the network to the host. The host
                 * becomes aware of the packets from the contents of the packet