GNU Linux-libre 5.10.215-gnu1

[releases.git] / drivers / net / ethernet / intel / e100.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 1999 - 2006 Intel Corporation. */

/*
 *      e100.c: Intel(R) PRO/100 ethernet driver
 *
 *      (Re)written 2003 by scott.feldman@intel.com.  Based loosely on
 *      original e100 driver, but better described as a munging of
 *      e100, e1000, eepro100, tg3, 8139cp, and other drivers.
 *
 *      References:
 *              Intel 8255x 10/100 Mbps Ethernet Controller Family,
 *              Open Source Software Developers Manual,
 *              http://sourceforge.net/projects/e1000
 *
 *
 *                            Theory of Operation
 *
 *      I.   General
 *
 *      The driver supports Intel(R) 10/100 Mbps PCI Fast Ethernet
 *      controller family, which includes the 82557, 82558, 82559, 82550,
 *      82551, and 82562 devices.  82558 and greater controllers
 *      integrate the Intel 82555 PHY.  The controllers are used in
 *      server and client network interface cards, as well as in
 *      LAN-On-Motherboard (LOM), CardBus, MiniPCI, and ICHx
 *      configurations.  8255x supports a 32-bit linear addressing
 *      mode and operates at 33Mhz PCI clock rate.
 *
 *      II.  Driver Operation
 *
 *      Memory-mapped mode is used exclusively to access the device's
 *      shared-memory structure, the Control/Status Registers (CSR). All
 *      setup, configuration, and control of the device, including queuing
 *      of Tx, Rx, and configuration commands is through the CSR.
 *      cmd_lock serializes accesses to the CSR command register.  cb_lock
 *      protects the shared Command Block List (CBL).
 *
 *      8255x is highly MII-compliant and all access to the PHY go
 *      through the Management Data Interface (MDI).  Consequently, the
 *      driver leverages the mii.c library shared with other MII-compliant
 *      devices.
 *
 *      Big- and Little-Endian byte order as well as 32- and 64-bit
 *      archs are supported.  Weak-ordered memory and non-cache-coherent
 *      archs are supported.
 *
 *      III. Transmit
 *
 *      A Tx skb is mapped and hangs off of a TCB.  TCBs are linked
 *      together in a fixed-size ring (CBL) thus forming the flexible mode
 *      memory structure.  A TCB marked with the suspend-bit indicates
 *      the end of the ring.  The last TCB processed suspends the
 *      controller, and the controller can be restarted by issue a CU
 *      resume command to continue from the suspend point, or a CU start
 *      command to start at a given position in the ring.
 *
 *      Non-Tx commands (config, multicast setup, etc) are linked
 *      into the CBL ring along with Tx commands.  The common structure
 *      used for both Tx and non-Tx commands is the Command Block (CB).
 *
 *      cb_to_use is the next CB to use for queuing a command; cb_to_clean
 *      is the next CB to check for completion; cb_to_send is the first
 *      CB to start on in case of a previous failure to resume.  CB clean
 *      up happens in interrupt context in response to a CU interrupt.
 *      cbs_avail keeps track of number of free CB resources available.
 *
 *      Hardware padding of short packets to minimum packet size is
 *      enabled.  82557 pads with 7Eh, while the later controllers pad
 *      with 00h.
 *
 *      IV.  Receive
 *
 *      The Receive Frame Area (RFA) comprises a ring of Receive Frame
 *      Descriptors (RFD) + data buffer, thus forming the simplified mode
 *      memory structure.  Rx skbs are allocated to contain both the RFD
 *      and the data buffer, but the RFD is pulled off before the skb is
 *      indicated.  The data buffer is aligned such that encapsulated
 *      protocol headers are u32-aligned.  Since the RFD is part of the
 *      mapped shared memory, and completion status is contained within
 *      the RFD, the RFD must be dma_sync'ed to maintain a consistent
 *      view from software and hardware.
 *
 *      In order to keep updates to the RFD link field from colliding with
 *      hardware writes to mark packets complete, we use the feature that
 *      hardware will not write to a size 0 descriptor and mark the previous
 *      packet as end-of-list (EL).   After updating the link, we remove EL
 *      and only then restore the size such that hardware may use the
 *      previous-to-end RFD.
 *
 *      Under typical operation, the  receive unit (RU) is start once,
 *      and the controller happily fills RFDs as frames arrive.  If
 *      replacement RFDs cannot be allocated, or the RU goes non-active,
 *      the RU must be restarted.  Frame arrival generates an interrupt,
 *      and Rx indication and re-allocation happen in the same context,
 *      therefore no locking is required.  A software-generated interrupt
 *      is generated from the watchdog to recover from a failed allocation
 *      scenario where all Rx resources have been indicated and none re-
 *      placed.
 *
 *      V.   Miscellaneous
 *
 *      VLAN offloading of tagging, stripping and filtering is not
 *      supported, but driver will accommodate the extra 4-byte VLAN tag
 *      for processing by upper layers.  Tx/Rx Checksum offloading is not
 *      supported.  Tx Scatter/Gather is not supported.  Jumbo Frames is
 *      not supported (hardware limitation).
 *
 *      MagicPacket(tm) WoL support is enabled/disabled via ethtool.
 *
 *      Thanks to JC (jchapman@katalix.com) for helping with
 *      testing/troubleshooting the development driver.
 *
 *      TODO:
 *      o several entry points race with dev->close
 *      o check for tx-no-resources/stop Q races with tx clean/wake Q
 *
 *      FIXES:
 * 2005/12/02 - Michael O'Donnell <Michael.ODonnell at stratus dot com>
 *      - Stratus87247: protect MDI control register manipulations
 * 2009/06/01 - Andreas Mohr <andi at lisas dot de>
 *      - add clean lowlevel I/O emulation for cards with MII-lacking PHYs
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/hardirq.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/mii.h>
#include <linux/if_vlan.h>
#include <linux/skbuff.h>
#include <linux/ethtool.h>
#include <linux/string.h>
#include <linux/firmware.h>
#include <linux/rtnetlink.h>
#include <asm/unaligned.h>


#define DRV_NAME                "e100"
#define DRV_DESCRIPTION         "Intel(R) PRO/100 Network Driver"
#define DRV_COPYRIGHT           "Copyright(c) 1999-2006 Intel Corporation"

#define E100_WATCHDOG_PERIOD    (2 * HZ)
#define E100_NAPI_WEIGHT        16

#define FIRMWARE_D101M          "/*(DEBLOBBED)*/"
#define FIRMWARE_D101S          "/*(DEBLOBBED)*/"
#define FIRMWARE_D102E          "/*(DEBLOBBED)*/"

MODULE_DESCRIPTION(DRV_DESCRIPTION);
MODULE_AUTHOR(DRV_COPYRIGHT);
MODULE_LICENSE("GPL v2");
/*(DEBLOBBED)*/

static int debug = 3;
static int eeprom_bad_csum_allow = 0;
static int use_io = 0;
module_param(debug, int, 0);
module_param(eeprom_bad_csum_allow, int, 0);
module_param(use_io, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
MODULE_PARM_DESC(eeprom_bad_csum_allow, "Allow bad eeprom checksums");
MODULE_PARM_DESC(use_io, "Force use of i/o access mode");

#define INTEL_8255X_ETHERNET_DEVICE(device_id, ich) {\
        PCI_VENDOR_ID_INTEL, device_id, PCI_ANY_ID, PCI_ANY_ID, \
        PCI_CLASS_NETWORK_ETHERNET << 8, 0xFFFF00, ich }
static const struct pci_device_id e100_id_table[] = {
        INTEL_8255X_ETHERNET_DEVICE(0x1029, 0),
        INTEL_8255X_ETHERNET_DEVICE(0x1030, 0),
        INTEL_8255X_ETHERNET_DEVICE(0x1031, 3),
        INTEL_8255X_ETHERNET_DEVICE(0x1032, 3),
        INTEL_8255X_ETHERNET_DEVICE(0x1033, 3),
        INTEL_8255X_ETHERNET_DEVICE(0x1034, 3),
        INTEL_8255X_ETHERNET_DEVICE(0x1038, 3),
        INTEL_8255X_ETHERNET_DEVICE(0x1039, 4),
        INTEL_8255X_ETHERNET_DEVICE(0x103A, 4),
        INTEL_8255X_ETHERNET_DEVICE(0x103B, 4),
        INTEL_8255X_ETHERNET_DEVICE(0x103C, 4),
        INTEL_8255X_ETHERNET_DEVICE(0x103D, 4),
        INTEL_8255X_ETHERNET_DEVICE(0x103E, 4),
        INTEL_8255X_ETHERNET_DEVICE(0x1050, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1051, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1052, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1053, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1054, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1055, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1056, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1057, 5),
        INTEL_8255X_ETHERNET_DEVICE(0x1059, 0),
        INTEL_8255X_ETHERNET_DEVICE(0x1064, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x1065, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x1066, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x1067, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x1068, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x1069, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x106A, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x106B, 6),
        INTEL_8255X_ETHERNET_DEVICE(0x1091, 7),
        INTEL_8255X_ETHERNET_DEVICE(0x1092, 7),
        INTEL_8255X_ETHERNET_DEVICE(0x1093, 7),
        INTEL_8255X_ETHERNET_DEVICE(0x1094, 7),
        INTEL_8255X_ETHERNET_DEVICE(0x1095, 7),
        INTEL_8255X_ETHERNET_DEVICE(0x10fe, 7),
        INTEL_8255X_ETHERNET_DEVICE(0x1209, 0),
        INTEL_8255X_ETHERNET_DEVICE(0x1229, 0),
        INTEL_8255X_ETHERNET_DEVICE(0x2449, 2),
        INTEL_8255X_ETHERNET_DEVICE(0x2459, 2),
        INTEL_8255X_ETHERNET_DEVICE(0x245D, 2),
        INTEL_8255X_ETHERNET_DEVICE(0x27DC, 7),
        { 0, }
};
MODULE_DEVICE_TABLE(pci, e100_id_table);

enum mac {
        mac_82557_D100_A  = 0,
        mac_82557_D100_B  = 1,
        mac_82557_D100_C  = 2,
        mac_82558_D101_A4 = 4,
        mac_82558_D101_B0 = 5,
        mac_82559_D101M   = 8,
        mac_82559_D101S   = 9,
        mac_82550_D102    = 12,
        mac_82550_D102_C  = 13,
        mac_82551_E       = 14,
        mac_82551_F       = 15,
        mac_82551_10      = 16,
        mac_unknown       = 0xFF,
};

enum phy {
        phy_100a     = 0x000003E0,
        phy_100c     = 0x035002A8,
        phy_82555_tx = 0x015002A8,
        phy_nsc_tx   = 0x5C002000,
        phy_82562_et = 0x033002A8,
        phy_82562_em = 0x032002A8,
        phy_82562_ek = 0x031002A8,
        phy_82562_eh = 0x017002A8,
        phy_82552_v  = 0xd061004d,
        phy_unknown  = 0xFFFFFFFF,
};

/* CSR (Control/Status Registers) */
struct csr {
        struct {
                u8 status;
                u8 stat_ack;
                u8 cmd_lo;
                u8 cmd_hi;
                u32 gen_ptr;
        } scb;
        u32 port;
        u16 flash_ctrl;
        u8 eeprom_ctrl_lo;
        u8 eeprom_ctrl_hi;
        u32 mdi_ctrl;
        u32 rx_dma_count;
};

enum scb_status {
        rus_no_res       = 0x08,
        rus_ready        = 0x10,
        rus_mask         = 0x3C,
};

enum ru_state  {
        RU_SUSPENDED = 0,
        RU_RUNNING       = 1,
        RU_UNINITIALIZED = -1,
};

enum scb_stat_ack {
        stat_ack_not_ours    = 0x00,
        stat_ack_sw_gen      = 0x04,
        stat_ack_rnr         = 0x10,
        stat_ack_cu_idle     = 0x20,
        stat_ack_frame_rx    = 0x40,
        stat_ack_cu_cmd_done = 0x80,
        stat_ack_not_present = 0xFF,
        stat_ack_rx = (stat_ack_sw_gen | stat_ack_rnr | stat_ack_frame_rx),
        stat_ack_tx = (stat_ack_cu_idle | stat_ack_cu_cmd_done),
};

enum scb_cmd_hi {
        irq_mask_none = 0x00,
        irq_mask_all  = 0x01,
        irq_sw_gen    = 0x02,
};

enum scb_cmd_lo {
        cuc_nop        = 0x00,
        ruc_start      = 0x01,
        ruc_load_base  = 0x06,
        cuc_start      = 0x10,
        cuc_resume     = 0x20,
        cuc_dump_addr  = 0x40,
        cuc_dump_stats = 0x50,
        cuc_load_base  = 0x60,
        cuc_dump_reset = 0x70,
};

enum cuc_dump {
        cuc_dump_complete       = 0x0000A005,
        cuc_dump_reset_complete = 0x0000A007,
};

enum port {
        software_reset  = 0x0000,
        selftest        = 0x0001,
        selective_reset = 0x0002,
};

enum eeprom_ctrl_lo {
        eesk = 0x01,
        eecs = 0x02,
        eedi = 0x04,
        eedo = 0x08,
};

enum mdi_ctrl {
        mdi_write = 0x04000000,
        mdi_read  = 0x08000000,
        mdi_ready = 0x10000000,
};

enum eeprom_op {
        op_write = 0x05,
        op_read  = 0x06,
        op_ewds  = 0x10,
        op_ewen  = 0x13,
};

enum eeprom_offsets {
        eeprom_cnfg_mdix  = 0x03,
        eeprom_phy_iface  = 0x06,
        eeprom_id         = 0x0A,
        eeprom_config_asf = 0x0D,
        eeprom_smbus_addr = 0x90,
};

enum eeprom_cnfg_mdix {
        eeprom_mdix_enabled = 0x0080,
};

enum eeprom_phy_iface {
        NoSuchPhy = 0,
        I82553AB,
        I82553C,
        I82503,
        DP83840,
        S80C240,
        S80C24,
        I82555,
        DP83840A = 10,
};

enum eeprom_id {
        eeprom_id_wol = 0x0020,
};

enum eeprom_config_asf {
        eeprom_asf = 0x8000,
        eeprom_gcl = 0x4000,
};

enum cb_status {
        cb_complete = 0x8000,
        cb_ok       = 0x2000,
};

/*
 * cb_command - Command Block flags
 * @cb_tx_nc:  0: controller does CRC (normal),  1: CRC from skb memory
 */
enum cb_command {
        cb_nop    = 0x0000,
        cb_iaaddr = 0x0001,
        cb_config = 0x0002,
        cb_multi  = 0x0003,
        cb_tx     = 0x0004,
        cb_ucode  = 0x0005,
        cb_dump   = 0x0006,
        cb_tx_sf  = 0x0008,
        cb_tx_nc  = 0x0010,
        cb_cid    = 0x1f00,
        cb_i      = 0x2000,
        cb_s      = 0x4000,
        cb_el     = 0x8000,
};

struct rfd {
        __le16 status;
        __le16 command;
        __le32 link;
        __le32 rbd;
        __le16 actual_size;
        __le16 size;
};

struct rx {
        struct rx *next, *prev;
        struct sk_buff *skb;
        dma_addr_t dma_addr;
};

#if defined(__BIG_ENDIAN_BITFIELD)
#define X(a,b)  b,a
#else
#define X(a,b)  a,b
#endif
struct config {
/*0*/   u8 X(byte_count:6, pad0:2);
/*1*/   u8 X(X(rx_fifo_limit:4, tx_fifo_limit:3), pad1:1);
/*2*/   u8 adaptive_ifs;
/*3*/   u8 X(X(X(X(mwi_enable:1, type_enable:1), read_align_enable:1),
           term_write_cache_line:1), pad3:4);
/*4*/   u8 X(rx_dma_max_count:7, pad4:1);
/*5*/   u8 X(tx_dma_max_count:7, dma_max_count_enable:1);
/*6*/   u8 X(X(X(X(X(X(X(late_scb_update:1, direct_rx_dma:1),
           tno_intr:1), cna_intr:1), standard_tcb:1), standard_stat_counter:1),
           rx_save_overruns : 1), rx_save_bad_frames : 1);
/*7*/   u8 X(X(X(X(X(rx_discard_short_frames:1, tx_underrun_retry:2),
           pad7:2), rx_extended_rfd:1), tx_two_frames_in_fifo:1),
           tx_dynamic_tbd:1);
/*8*/   u8 X(X(mii_mode:1, pad8:6), csma_disabled:1);
/*9*/   u8 X(X(X(X(X(rx_tcpudp_checksum:1, pad9:3), vlan_arp_tco:1),
           link_status_wake:1), arp_wake:1), mcmatch_wake:1);
/*10*/  u8 X(X(X(pad10:3, no_source_addr_insertion:1), preamble_length:2),
           loopback:2);
/*11*/  u8 X(linear_priority:3, pad11:5);
/*12*/  u8 X(X(linear_priority_mode:1, pad12:3), ifs:4);
/*13*/  u8 ip_addr_lo;
/*14*/  u8 ip_addr_hi;
/*15*/  u8 X(X(X(X(X(X(X(promiscuous_mode:1, broadcast_disabled:1),
           wait_after_win:1), pad15_1:1), ignore_ul_bit:1), crc_16_bit:1),
           pad15_2:1), crs_or_cdt:1);
/*16*/  u8 fc_delay_lo;
/*17*/  u8 fc_delay_hi;
/*18*/  u8 X(X(X(X(X(rx_stripping:1, tx_padding:1), rx_crc_transfer:1),
           rx_long_ok:1), fc_priority_threshold:3), pad18:1);
/*19*/  u8 X(X(X(X(X(X(X(addr_wake:1, magic_packet_disable:1),
           fc_disable:1), fc_restop:1), fc_restart:1), fc_reject:1),
           full_duplex_force:1), full_duplex_pin:1);
/*20*/  u8 X(X(X(pad20_1:5, fc_priority_location:1), multi_ia:1), pad20_2:1);
/*21*/  u8 X(X(pad21_1:3, multicast_all:1), pad21_2:4);
/*22*/  u8 X(X(rx_d102_mode:1, rx_vlan_drop:1), pad22:6);
        u8 pad_d102[9];
};

#define E100_MAX_MULTICAST_ADDRS        64
struct multi {
        __le16 count;
        u8 addr[E100_MAX_MULTICAST_ADDRS * ETH_ALEN + 2/*pad*/];
};

/* Important: keep total struct u32-aligned */
#define UCODE_SIZE                      134
struct cb {
        __le16 status;
        __le16 command;
        __le32 link;
        union {
                u8 iaaddr[ETH_ALEN];
                __le32 ucode[UCODE_SIZE];
                struct config config;
                struct multi multi;
                struct {
                        u32 tbd_array;
                        u16 tcb_byte_count;
                        u8 threshold;
                        u8 tbd_count;
                        struct {
                                __le32 buf_addr;
                                __le16 size;
                                u16 eol;
                        } tbd;
                } tcb;
                __le32 dump_buffer_addr;
        } u;
        struct cb *next, *prev;
        dma_addr_t dma_addr;
        struct sk_buff *skb;
};

enum loopback {
        lb_none = 0, lb_mac = 1, lb_phy = 3,
};

struct stats {
        __le32 tx_good_frames, tx_max_collisions, tx_late_collisions,
                tx_underruns, tx_lost_crs, tx_deferred, tx_single_collisions,
                tx_multiple_collisions, tx_total_collisions;
        __le32 rx_good_frames, rx_crc_errors, rx_alignment_errors,
                rx_resource_errors, rx_overrun_errors, rx_cdt_errors,
                rx_short_frame_errors;
        __le32 fc_xmt_pause, fc_rcv_pause, fc_rcv_unsupported;
        __le16 xmt_tco_frames, rcv_tco_frames;
        __le32 complete;
};

struct mem {
        struct {
                u32 signature;
                u32 result;
        } selftest;
        struct stats stats;
        u8 dump_buf[596];
};

struct param_range {
        u32 min;
        u32 max;
        u32 count;
};

struct params {
        struct param_range rfds;
        struct param_range cbs;
};

struct nic {
        /* Begin: frequently used values: keep adjacent for cache effect */
        u32 msg_enable                          ____cacheline_aligned;
        struct net_device *netdev;
        struct pci_dev *pdev;
        u16 (*mdio_ctrl)(struct nic *nic, u32 addr, u32 dir, u32 reg, u16 data);

        struct rx *rxs                          ____cacheline_aligned;
        struct rx *rx_to_use;
        struct rx *rx_to_clean;
        struct rfd blank_rfd;
        enum ru_state ru_running;

        spinlock_t cb_lock                      ____cacheline_aligned;
        spinlock_t cmd_lock;
        struct csr __iomem *csr;
        enum scb_cmd_lo cuc_cmd;
        unsigned int cbs_avail;
        struct napi_struct napi;
        struct cb *cbs;
        struct cb *cb_to_use;
        struct cb *cb_to_send;
        struct cb *cb_to_clean;
        __le16 tx_command;
        /* End: frequently used values: keep adjacent for cache effect */

        enum {
                ich                = (1 << 0),
                promiscuous        = (1 << 1),
                multicast_all      = (1 << 2),
                wol_magic          = (1 << 3),
                ich_10h_workaround = (1 << 4),
        } flags                                 ____cacheline_aligned;

        enum mac mac;
        enum phy phy;
        struct params params;
        struct timer_list watchdog;
        struct mii_if_info mii;
        struct work_struct tx_timeout_task;
        enum loopback loopback;

        struct mem *mem;
        dma_addr_t dma_addr;

        struct dma_pool *cbs_pool;
        dma_addr_t cbs_dma_addr;
        u8 adaptive_ifs;
        u8 tx_threshold;
        u32 tx_frames;
        u32 tx_collisions;
        u32 tx_deferred;
        u32 tx_single_collisions;
        u32 tx_multiple_collisions;
        u32 tx_fc_pause;
        u32 tx_tco_frames;

        u32 rx_fc_pause;
        u32 rx_fc_unsupported;
        u32 rx_tco_frames;
        u32 rx_short_frame_errors;
        u32 rx_over_length_errors;

        u16 eeprom_wc;
        __le16 eeprom[256];
        spinlock_t mdio_lock;
        const struct firmware *fw;
};

static inline void e100_write_flush(struct nic *nic)
{
        /* Flush previous PCI writes through intermediate bridges
         * by doing a benign read */
        (void)ioread8(&nic->csr->scb.status);
}

static void e100_enable_irq(struct nic *nic)
{
        unsigned long flags;

        spin_lock_irqsave(&nic->cmd_lock, flags);
        iowrite8(irq_mask_none, &nic->csr->scb.cmd_hi);
        e100_write_flush(nic);
        spin_unlock_irqrestore(&nic->cmd_lock, flags);
}

static void e100_disable_irq(struct nic *nic)
{
        unsigned long flags;

        spin_lock_irqsave(&nic->cmd_lock, flags);
        iowrite8(irq_mask_all, &nic->csr->scb.cmd_hi);
        e100_write_flush(nic);
        spin_unlock_irqrestore(&nic->cmd_lock, flags);
}

static void e100_hw_reset(struct nic *nic)
{
        /* Put CU and RU into idle with a selective reset to get
         * device off of PCI bus */
        iowrite32(selective_reset, &nic->csr->port);
        e100_write_flush(nic); udelay(20);

        /* Now fully reset device */
        iowrite32(software_reset, &nic->csr->port);
        e100_write_flush(nic); udelay(20);

        /* Mask off our interrupt line - it's unmasked after reset */
        e100_disable_irq(nic);
}

static int e100_self_test(struct nic *nic)
{
        u32 dma_addr = nic->dma_addr + offsetof(struct mem, selftest);

        /* Passing the self-test is a pretty good indication
         * that the device can DMA to/from host memory */

        nic->mem->selftest.signature = 0;
        nic->mem->selftest.result = 0xFFFFFFFF;

        iowrite32(selftest | dma_addr, &nic->csr->port);
        e100_write_flush(nic);
        /* Wait 10 msec for self-test to complete */
        msleep(10);

        /* Interrupts are enabled after self-test */
        e100_disable_irq(nic);

        /* Check results of self-test */
        if (nic->mem->selftest.result != 0) {
                netif_err(nic, hw, nic->netdev,
                          "Self-test failed: result=0x%08X\n",
                          nic->mem->selftest.result);
                return -ETIMEDOUT;
        }
        if (nic->mem->selftest.signature == 0) {
                netif_err(nic, hw, nic->netdev, "Self-test failed: timed out\n");
                return -ETIMEDOUT;
        }

        return 0;
}

static void e100_eeprom_write(struct nic *nic, u16 addr_len, u16 addr, __le16 data)
{
        u32 cmd_addr_data[3];
        u8 ctrl;
        int i, j;

        /* Three cmds: write/erase enable, write data, write/erase disable */
        cmd_addr_data[0] = op_ewen << (addr_len - 2);
        cmd_addr_data[1] = (((op_write << addr_len) | addr) << 16) |
                le16_to_cpu(data);
        cmd_addr_data[2] = op_ewds << (addr_len - 2);

        /* Bit-bang cmds to write word to eeprom */
        for (j = 0; j < 3; j++) {

                /* Chip select */
                iowrite8(eecs | eesk, &nic->csr->eeprom_ctrl_lo);
                e100_write_flush(nic); udelay(4);

                for (i = 31; i >= 0; i--) {
                        ctrl = (cmd_addr_data[j] & (1 << i)) ?
                                eecs | eedi : eecs;
                        iowrite8(ctrl, &nic->csr->eeprom_ctrl_lo);
                        e100_write_flush(nic); udelay(4);

                        iowrite8(ctrl | eesk, &nic->csr->eeprom_ctrl_lo);
                        e100_write_flush(nic); udelay(4);
                }
                /* Wait 10 msec for cmd to complete */
                msleep(10);

                /* Chip deselect */
                iowrite8(0, &nic->csr->eeprom_ctrl_lo);
                e100_write_flush(nic); udelay(4);
        }
};

/* General technique stolen from the eepro100 driver - very clever */
static __le16 e100_eeprom_read(struct nic *nic, u16 *addr_len, u16 addr)
{
        u32 cmd_addr_data;
        u16 data = 0;
        u8 ctrl;
        int i;

        cmd_addr_data = ((op_read << *addr_len) | addr) << 16;

        /* Chip select */
        iowrite8(eecs | eesk, &nic->csr->eeprom_ctrl_lo);
        e100_write_flush(nic); udelay(4);

        /* Bit-bang to read word from eeprom */
        for (i = 31; i >= 0; i--) {
                ctrl = (cmd_addr_data & (1 << i)) ? eecs | eedi : eecs;
                iowrite8(ctrl, &nic->csr->eeprom_ctrl_lo);
                e100_write_flush(nic); udelay(4);

                iowrite8(ctrl | eesk, &nic->csr->eeprom_ctrl_lo);
                e100_write_flush(nic); udelay(4);

                /* Eeprom drives a dummy zero to EEDO after receiving
                 * complete address.  Use this to adjust addr_len. */
                ctrl = ioread8(&nic->csr->eeprom_ctrl_lo);
                if (!(ctrl & eedo) && i > 16) {
                        *addr_len -= (i - 16);
                        i = 17;
                }

                data = (data << 1) | (ctrl & eedo ? 1 : 0);
        }

        /* Chip deselect */
        iowrite8(0, &nic->csr->eeprom_ctrl_lo);
        e100_write_flush(nic); udelay(4);

        return cpu_to_le16(data);
};

/* Load entire EEPROM image into driver cache and validate checksum */
static int e100_eeprom_load(struct nic *nic)
{
        u16 addr, addr_len = 8, checksum = 0;

        /* Try reading with an 8-bit addr len to discover actual addr len */
        e100_eeprom_read(nic, &addr_len, 0);
        nic->eeprom_wc = 1 << addr_len;

        for (addr = 0; addr < nic->eeprom_wc; addr++) {
                nic->eeprom[addr] = e100_eeprom_read(nic, &addr_len, addr);
                if (addr < nic->eeprom_wc - 1)
                        checksum += le16_to_cpu(nic->eeprom[addr]);
        }

        /* The checksum, stored in the last word, is calculated such that
         * the sum of words should be 0xBABA */
        if (cpu_to_le16(0xBABA - checksum) != nic->eeprom[nic->eeprom_wc - 1]) {
                netif_err(nic, probe, nic->netdev, "EEPROM corrupted\n");
                if (!eeprom_bad_csum_allow)
                        return -EAGAIN;
        }

        return 0;
}

/* Save (portion of) driver EEPROM cache to device and update checksum */
static int e100_eeprom_save(struct nic *nic, u16 start, u16 count)
{
        u16 addr, addr_len = 8, checksum = 0;

        /* Try reading with an 8-bit addr len to discover actual addr len */
        e100_eeprom_read(nic, &addr_len, 0);
        nic->eeprom_wc = 1 << addr_len;

        if (start + count >= nic->eeprom_wc)
                return -EINVAL;

        for (addr = start; addr < start + count; addr++)
                e100_eeprom_write(nic, addr_len, addr, nic->eeprom[addr]);

        /* The checksum, stored in the last word, is calculated such that
         * the sum of words should be 0xBABA */
        for (addr = 0; addr < nic->eeprom_wc - 1; addr++)
                checksum += le16_to_cpu(nic->eeprom[addr]);
        nic->eeprom[nic->eeprom_wc - 1] = cpu_to_le16(0xBABA - checksum);
        e100_eeprom_write(nic, addr_len, nic->eeprom_wc - 1,
                nic->eeprom[nic->eeprom_wc - 1]);

        return 0;
}

#define E100_WAIT_SCB_TIMEOUT 20000 /* we might have to wait 100ms!!! */
#define E100_WAIT_SCB_FAST 20       /* delay like the old code */
static int e100_exec_cmd(struct nic *nic, u8 cmd, dma_addr_t dma_addr)
{
        unsigned long flags;
        unsigned int i;
        int err = 0;

        spin_lock_irqsave(&nic->cmd_lock, flags);

        /* Previous command is accepted when SCB clears */
        for (i = 0; i < E100_WAIT_SCB_TIMEOUT; i++) {
                if (likely(!ioread8(&nic->csr->scb.cmd_lo)))
                        break;
                cpu_relax();
                if (unlikely(i > E100_WAIT_SCB_FAST))
                        udelay(5);
        }
        if (unlikely(i == E100_WAIT_SCB_TIMEOUT)) {
                err = -EAGAIN;
                goto err_unlock;
        }

        if (unlikely(cmd != cuc_resume))
                iowrite32(dma_addr, &nic->csr->scb.gen_ptr);
        iowrite8(cmd, &nic->csr->scb.cmd_lo);

err_unlock:
        spin_unlock_irqrestore(&nic->cmd_lock, flags);

        return err;
}

static int e100_exec_cb(struct nic *nic, struct sk_buff *skb,
        int (*cb_prepare)(struct nic *, struct cb *, struct sk_buff *))
{
        struct cb *cb;
        unsigned long flags;
        int err;

        spin_lock_irqsave(&nic->cb_lock, flags);

        if (unlikely(!nic->cbs_avail)) {
                err = -ENOMEM;
                goto err_unlock;
        }

        cb = nic->cb_to_use;
        nic->cb_to_use = cb->next;
        nic->cbs_avail--;
        cb->skb = skb;

        err = cb_prepare(nic, cb, skb);
        if (err)
                goto err_unlock;

        if (unlikely(!nic->cbs_avail))
                err = -ENOSPC;


        /* Order is important otherwise we'll be in a race with h/w:
         * set S-bit in current first, then clear S-bit in previous. */
        cb->command |= cpu_to_le16(cb_s);
        dma_wmb();
        cb->prev->command &= cpu_to_le16(~cb_s);

        while (nic->cb_to_send != nic->cb_to_use) {
                if (unlikely(e100_exec_cmd(nic, nic->cuc_cmd,
                        nic->cb_to_send->dma_addr))) {
                        /* Ok, here's where things get sticky.  It's
                         * possible that we can't schedule the command
                         * because the controller is too busy, so
                         * let's just queue the command and try again
                         * when another command is scheduled. */
                        if (err == -ENOSPC) {
                                //request a reset
                                schedule_work(&nic->tx_timeout_task);
                        }
                        break;
                } else {
                        nic->cuc_cmd = cuc_resume;
                        nic->cb_to_send = nic->cb_to_send->next;
                }
        }

err_unlock:
        spin_unlock_irqrestore(&nic->cb_lock, flags);

        return err;
}

static int mdio_read(struct net_device *netdev, int addr, int reg)
{
        struct nic *nic = netdev_priv(netdev);
        return nic->mdio_ctrl(nic, addr, mdi_read, reg, 0);
}

static void mdio_write(struct net_device *netdev, int addr, int reg, int data)
{
        struct nic *nic = netdev_priv(netdev);

        nic->mdio_ctrl(nic, addr, mdi_write, reg, data);
}

/* the standard mdio_ctrl() function for usual MII-compliant hardware */
static u16 mdio_ctrl_hw(struct nic *nic, u32 addr, u32 dir, u32 reg, u16 data)
{
        u32 data_out = 0;
        unsigned int i;
        unsigned long flags;


        /*
         * Stratus87247: we shouldn't be writing the MDI control
         * register until the Ready bit shows True.  Also, since
         * manipulation of the MDI control registers is a multi-step
         * procedure it should be done under lock.
         */
        spin_lock_irqsave(&nic->mdio_lock, flags);
        for (i = 100; i; --i) {
                if (ioread32(&nic->csr->mdi_ctrl) & mdi_ready)
                        break;
                udelay(20);
        }
        if (unlikely(!i)) {
                netdev_err(nic->netdev, "e100.mdio_ctrl won't go Ready\n");
                spin_unlock_irqrestore(&nic->mdio_lock, flags);
                return 0;               /* No way to indicate timeout error */
        }
        iowrite32((reg << 16) | (addr << 21) | dir | data, &nic->csr->mdi_ctrl);

        for (i = 0; i < 100; i++) {
                udelay(20);
                if ((data_out = ioread32(&nic->csr->mdi_ctrl)) & mdi_ready)
                        break;
        }
        spin_unlock_irqrestore(&nic->mdio_lock, flags);
        netif_printk(nic, hw, KERN_DEBUG, nic->netdev,
                     "%s:addr=%d, reg=%d, data_in=0x%04X, data_out=0x%04X\n",
                     dir == mdi_read ? "READ" : "WRITE",
                     addr, reg, data, data_out);
        return (u16)data_out;
}

/* slightly tweaked mdio_ctrl() function for phy_82552_v specifics */
static u16 mdio_ctrl_phy_82552_v(struct nic *nic,
                                 u32 addr,
                                 u32 dir,
                                 u32 reg,
                                 u16 data)
{
        if ((reg == MII_BMCR) && (dir == mdi_write)) {
                if (data & (BMCR_ANRESTART | BMCR_ANENABLE)) {
                        u16 advert = mdio_read(nic->netdev, nic->mii.phy_id,
                                                        MII_ADVERTISE);

                        /*
                         * Workaround Si issue where sometimes the part will not
                         * autoneg to 100Mbps even when advertised.
                         */
                        if (advert & ADVERTISE_100FULL)
                                data |= BMCR_SPEED100 | BMCR_FULLDPLX;
                        else if (advert & ADVERTISE_100HALF)
                                data |= BMCR_SPEED100;
                }
        }
        return mdio_ctrl_hw(nic, addr, dir, reg, data);
}

/* Fully software-emulated mdio_ctrl() function for cards without
 * MII-compliant PHYs.
 * For now, this is mainly geared towards 80c24 support; in case of further
 * requirements for other types (i82503, ...?) either extend this mechanism
 * or split it, whichever is cleaner.
 */
static u16 mdio_ctrl_phy_mii_emulated(struct nic *nic,
                                      u32 addr,
                                      u32 dir,
                                      u32 reg,
                                      u16 data)
{
        /* might need to allocate a netdev_priv'ed register array eventually
         * to be able to record state changes, but for now
         * some fully hardcoded register handling ought to be ok I guess. */

        if (dir == mdi_read) {
                switch (reg) {
                case MII_BMCR:
                        /* Auto-negotiation, right? */
                        return  BMCR_ANENABLE |
                                BMCR_FULLDPLX;
                case MII_BMSR:
                        return  BMSR_LSTATUS /* for mii_link_ok() */ |
                                BMSR_ANEGCAPABLE |
                                BMSR_10FULL;
                case MII_ADVERTISE:
                        /* 80c24 is a "combo card" PHY, right? */
                        return  ADVERTISE_10HALF |
                                ADVERTISE_10FULL;
                default:
                        netif_printk(nic, hw, KERN_DEBUG, nic->netdev,
                                     "%s:addr=%d, reg=%d, data=0x%04X: unimplemented emulation!\n",
                                     dir == mdi_read ? "READ" : "WRITE",
                                     addr, reg, data);
                        return 0xFFFF;
                }
        } else {
                switch (reg) {
                default:
                        netif_printk(nic, hw, KERN_DEBUG, nic->netdev,
                                     "%s:addr=%d, reg=%d, data=0x%04X: unimplemented emulation!\n",
                                     dir == mdi_read ? "READ" : "WRITE",
                                     addr, reg, data);
                        return 0xFFFF;
                }
        }
}
static inline int e100_phy_supports_mii(struct nic *nic)
{
        /* for now, just check it by comparing whether we
           are using MII software emulation.
        */
        return (nic->mdio_ctrl != mdio_ctrl_phy_mii_emulated);
}

static void e100_get_defaults(struct nic *nic)
{
        struct param_range rfds = { .min = 16, .max = 256, .count = 256 };
        struct param_range cbs  = { .min = 64, .max = 256, .count = 128 };

        /* MAC type is encoded as rev ID; exception: ICH is treated as 82559 */
        nic->mac = (nic->flags & ich) ? mac_82559_D101M : nic->pdev->revision;
        if (nic->mac == mac_unknown)
                nic->mac = mac_82557_D100_A;

        nic->params.rfds = rfds;
        nic->params.cbs = cbs;

        /* Quadwords to DMA into FIFO before starting frame transmit */
        nic->tx_threshold = 0xE0;

        /* no interrupt for every tx completion, delay = 256us if not 557 */
        nic->tx_command = cpu_to_le16(cb_tx | cb_tx_sf |
                ((nic->mac >= mac_82558_D101_A4) ? cb_cid : cb_i));

        /* Template for a freshly allocated RFD */
        nic->blank_rfd.command = 0;
        nic->blank_rfd.rbd = cpu_to_le32(0xFFFFFFFF);
        nic->blank_rfd.size = cpu_to_le16(VLAN_ETH_FRAME_LEN + ETH_FCS_LEN);

        /* MII setup */
        nic->mii.phy_id_mask = 0x1F;
        nic->mii.reg_num_mask = 0x1F;
        nic->mii.dev = nic->netdev;
        nic->mii.mdio_read = mdio_read;
        nic->mii.mdio_write = mdio_write;
}

static int e100_configure(struct nic *nic, struct cb *cb, struct sk_buff *skb)
{
        struct config *config = &cb->u.config;
        u8 *c = (u8 *)config;
        struct net_device *netdev = nic->netdev;

        cb->command = cpu_to_le16(cb_config);

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

        config->byte_count = 0x16;              /* bytes in this struct */
        config->rx_fifo_limit = 0x8;            /* bytes in FIFO before DMA */
        config->direct_rx_dma = 0x1;            /* reserved */
        config->standard_tcb = 0x1;             /* 1=standard, 0=extended */
        config->standard_stat_counter = 0x1;    /* 1=standard, 0=extended */
        config->rx_discard_short_frames = 0x1;  /* 1=discard, 0=pass */
        config->tx_underrun_retry = 0x3;        /* # of underrun retries */
        if (e100_phy_supports_mii(nic))
                config->mii_mode = 1;           /* 1=MII mode, 0=i82503 mode */
        config->pad10 = 0x6;
        config->no_source_addr_insertion = 0x1; /* 1=no, 0=yes */
        config->preamble_length = 0x2;          /* 0=1, 1=3, 2=7, 3=15 bytes */
        config->ifs = 0x6;                      /* x16 = inter frame spacing */
        config->ip_addr_hi = 0xF2;              /* ARP IP filter - not used */
        config->pad15_1 = 0x1;
        config->pad15_2 = 0x1;
        config->crs_or_cdt = 0x0;               /* 0=CRS only, 1=CRS or CDT */
        config->fc_delay_hi = 0x40;             /* time delay for fc frame */
        config->tx_padding = 0x1;               /* 1=pad short frames */
        config->fc_priority_threshold = 0x7;    /* 7=priority fc disabled */
        config->pad18 = 0x1;
        config->full_duplex_pin = 0x1;          /* 1=examine FDX# pin */
        config->pad20_1 = 0x1F;
        config->fc_priority_location = 0x1;     /* 1=byte#31, 0=byte#19 */
        config->pad21_1 = 0x5;

        config->adaptive_ifs = nic->adaptive_ifs;
        config->loopback = nic->loopback;

        if (nic->mii.force_media && nic->mii.full_duplex)
                config->full_duplex_force = 0x1;        /* 1=force, 0=auto */

        if (nic->flags & promiscuous || nic->loopback) {
                config->rx_save_bad_frames = 0x1;       /* 1=save, 0=discard */
                config->rx_discard_short_frames = 0x0;  /* 1=discard, 0=save */
                config->promiscuous_mode = 0x1;         /* 1=on, 0=off */
        }

        if (unlikely(netdev->features & NETIF_F_RXFCS))
                config->rx_crc_transfer = 0x1;  /* 1=save, 0=discard */

        if (nic->flags & multicast_all)
                config->multicast_all = 0x1;            /* 1=accept, 0=no */

        /* disable WoL when up */
        if (netif_running(nic->netdev) || !(nic->flags & wol_magic))
                config->magic_packet_disable = 0x1;     /* 1=off, 0=on */

        if (nic->mac >= mac_82558_D101_A4) {
                config->fc_disable = 0x1;       /* 1=Tx fc off, 0=Tx fc on */
                config->mwi_enable = 0x1;       /* 1=enable, 0=disable */
                config->standard_tcb = 0x0;     /* 1=standard, 0=extended */
                config->rx_long_ok = 0x1;       /* 1=VLANs ok, 0=standard */
                if (nic->mac >= mac_82559_D101M) {
                        config->tno_intr = 0x1;         /* TCO stats enable */
                        /* Enable TCO in extended config */
                        if (nic->mac >= mac_82551_10) {
                                config->byte_count = 0x20; /* extended bytes */
                                config->rx_d102_mode = 0x1; /* GMRC for TCO */
                        }
                } else {
                        config->standard_stat_counter = 0x0;
                }
        }

        if (netdev->features & NETIF_F_RXALL) {
                config->rx_save_overruns = 0x1; /* 1=save, 0=discard */
                config->rx_save_bad_frames = 0x1;       /* 1=save, 0=discard */
                config->rx_discard_short_frames = 0x0;  /* 1=discard, 0=save */
        }

        netif_printk(nic, hw, KERN_DEBUG, nic->netdev, "[00-07]=%8ph\n",
                     c + 0);
        netif_printk(nic, hw, KERN_DEBUG, nic->netdev, "[08-15]=%8ph\n",
                     c + 8);
        netif_printk(nic, hw, KERN_DEBUG, nic->netdev, "[16-23]=%8ph\n",
                     c + 16);
        return 0;
}

/*************************************************************************
*  CPUSaver parameters
*
*  All CPUSaver parameters are 16-bit literals that are part of a
*  "move immediate value" instruction.  By changing the value of
*  the literal in the instruction before the code is loaded, the
*  driver can change the algorithm.
*
*  INTDELAY - This loads the dead-man timer with its initial value.
*    When this timer expires the interrupt is asserted, and the
*    timer is reset each time a new packet is received.  (see
*    BUNDLEMAX below to set the limit on number of chained packets)
*    The current default is 0x600 or 1536.  Experiments show that
*    the value should probably stay within the 0x200 - 0x1000.
*
*  BUNDLEMAX -
*    This sets the maximum number of frames that will be bundled.  In
*    some situations, such as the TCP windowing algorithm, it may be
*    better to limit the growth of the bundle size than let it go as
*    high as it can, because that could cause too much added latency.
*    The default is six, because this is the number of packets in the
*    default TCP window size.  A value of 1 would make CPUSaver indicate
*    an interrupt for every frame received.  If you do not want to put
*    a limit on the bundle size, set this value to xFFFF.
*
*  BUNDLESMALL -
*    This contains a bit-mask describing the minimum size frame that
*    will be bundled.  The default masks the lower 7 bits, which means
*    that any frame less than 128 bytes in length will not be bundled,
*    but will instead immediately generate an interrupt.  This does
*    not affect the current bundle in any way.  Any frame that is 128
*    bytes or large will be bundled normally.  This feature is meant
*    to provide immediate indication of ACK frames in a TCP environment.
*    Customers were seeing poor performance when a machine with CPUSaver
*    enabled was sending but not receiving.  The delay introduced when
*    the ACKs were received was enough to reduce total throughput, because
*    the sender would sit idle until the ACK was finally seen.
*
*    The current default is 0xFF80, which masks out the lower 7 bits.
*    This means that any frame which is x7F (127) bytes or smaller
*    will cause an immediate interrupt.  Because this value must be a
*    bit mask, there are only a few valid values that can be used.  To
*    turn this feature off, the driver can write the value xFFFF to the
*    lower word of this instruction (in the same way that the other
*    parameters are used).  Likewise, a value of 0xF800 (2047) would
*    cause an interrupt to be generated for every frame, because all
*    standard Ethernet frames are <= 2047 bytes in length.
*************************************************************************/

/* if you wish to disable the ucode functionality, while maintaining the
 * workarounds it provides, set the following defines to:
 * BUNDLESMALL 0
 * BUNDLEMAX 1
 * INTDELAY 1
 */
#define BUNDLESMALL 1
#define BUNDLEMAX (u16)6
#define INTDELAY (u16)1536 /* 0x600 */

/* Initialize firmware */
static const struct firmware *e100_request_firmware(struct nic *nic)
{
        const char *fw_name;
        const struct firmware *fw = nic->fw;
        u8 timer, bundle, min_size;
        int err = 0;
        bool required = false;

        /* do not load u-code for ICH devices */
        if (nic->flags & ich)
                return NULL;

        /* Search for ucode match against h/w revision
         *
         * Based on comments in the source code for the FreeBSD fxp
         * driver, the FIRMWARE_D102E ucode includes both CPUSaver and
         *
         *    "fixes for bugs in the B-step hardware (specifically, bugs
         *     with Inline Receive)."
         *
         * So we must fail if it cannot be loaded.
         *
         * The other microcode files are only required for the optional
         * CPUSaver feature.  Nice to have, but no reason to fail.
         */
        if (nic->mac == mac_82559_D101M) {
                fw_name = FIRMWARE_D101M;
        } else if (nic->mac == mac_82559_D101S) {
                fw_name = FIRMWARE_D101S;
        } else if (nic->mac == mac_82551_F || nic->mac == mac_82551_10) {
                fw_name = FIRMWARE_D102E;
                required = true;
        } else { /* No ucode on other devices */
                return NULL;
        }

        /* If the firmware has not previously been loaded, request a pointer
         * to it. If it was previously loaded, we are reinitializing the
         * adapter, possibly in a resume from hibernate, in which case
         * reject_firmware() cannot be used.
         */
        if (!fw)
                err = reject_firmware(&fw, fw_name, &nic->pdev->dev);

        if (err) {
                if (required) {
                        netif_err(nic, probe, nic->netdev,
                                  "Failed to load firmware \"%s\": %d\n",
                                  fw_name, err);
                        netif_err(nic, probe, nic->netdev, "Proceeding without firmware\n");
                        return NULL;
                } else {
                        netif_info(nic, probe, nic->netdev,
                                   "CPUSaver disabled. Needs \"%s\": %d\n",
                                   fw_name, err);
                        return NULL;
                }
        }

        /* Firmware should be precisely UCODE_SIZE (words) plus three bytes
           indicating the offsets for BUNDLESMALL, BUNDLEMAX, INTDELAY */
        if (fw->size != UCODE_SIZE * 4 + 3) {
                netif_err(nic, probe, nic->netdev,
                          "Firmware \"%s\" has wrong size %zu\n",
                          fw_name, fw->size);
                release_firmware(fw);
                return ERR_PTR(-EINVAL);
        }

        /* Read timer, bundle and min_size from end of firmware blob */
        timer = fw->data[UCODE_SIZE * 4];
        bundle = fw->data[UCODE_SIZE * 4 + 1];
        min_size = fw->data[UCODE_SIZE * 4 + 2];

        if (timer >= UCODE_SIZE || bundle >= UCODE_SIZE ||
            min_size >= UCODE_SIZE) {
                netif_err(nic, probe, nic->netdev,
                          "\"%s\" has bogus offset values (0x%x,0x%x,0x%x)\n",
                          fw_name, timer, bundle, min_size);
                release_firmware(fw);
                return ERR_PTR(-EINVAL);
        }

        /* OK, firmware is validated and ready to use. Save a pointer
         * to it in the nic */
        nic->fw = fw;
        return fw;
}

static int e100_setup_ucode(struct nic *nic, struct cb *cb,
                             struct sk_buff *skb)
{
        const struct firmware *fw = (void *)skb;
        u8 timer, bundle, min_size;

        /* It's not a real skb; we just abused the fact that e100_exec_cb
           will pass it through to here... */
        cb->skb = NULL;

        /* firmware is stored as little endian already */
        memcpy(cb->u.ucode, fw->data, UCODE_SIZE * 4);

        /* Read timer, bundle and min_size from end of firmware blob */
        timer = fw->data[UCODE_SIZE * 4];
        bundle = fw->data[UCODE_SIZE * 4 + 1];
        min_size = fw->data[UCODE_SIZE * 4 + 2];

        /* Insert user-tunable settings in cb->u.ucode */
        cb->u.ucode[timer] &= cpu_to_le32(0xFFFF0000);
        cb->u.ucode[timer] |= cpu_to_le32(INTDELAY);
        cb->u.ucode[bundle] &= cpu_to_le32(0xFFFF0000);
        cb->u.ucode[bundle] |= cpu_to_le32(BUNDLEMAX);
        cb->u.ucode[min_size] &= cpu_to_le32(0xFFFF0000);
        cb->u.ucode[min_size] |= cpu_to_le32((BUNDLESMALL) ? 0xFFFF : 0xFF80);

        cb->command = cpu_to_le16(cb_ucode | cb_el);
        return 0;
}

static inline int e100_load_ucode_wait(struct nic *nic)
{
        const struct firmware *fw;
        int err = 0, counter = 50;
        struct cb *cb = nic->cb_to_clean;

        fw = e100_request_firmware(nic);
        /* If it's NULL, then no ucode is required */
        if (IS_ERR_OR_NULL(fw))
                return PTR_ERR_OR_ZERO(fw);

        if ((err = e100_exec_cb(nic, (void *)fw, e100_setup_ucode)))
                netif_err(nic, probe, nic->netdev,
                          "ucode cmd failed with error %d\n", err);

        /* must restart cuc */
        nic->cuc_cmd = cuc_start;

        /* wait for completion */
        e100_write_flush(nic);
        udelay(10);

        /* wait for possibly (ouch) 500ms */
        while (!(cb->status & cpu_to_le16(cb_complete))) {
                msleep(10);
                if (!--counter) break;
        }

        /* ack any interrupts, something could have been set */
        iowrite8(~0, &nic->csr->scb.stat_ack);

        /* if the command failed, or is not OK, notify and return */
        if (!counter || !(cb->status & cpu_to_le16(cb_ok))) {
                netif_err(nic, probe, nic->netdev, "ucode load failed\n");
                err = -EPERM;
        }

        return err;
}

static int e100_setup_iaaddr(struct nic *nic, struct cb *cb,
        struct sk_buff *skb)
{
        cb->command = cpu_to_le16(cb_iaaddr);
        memcpy(cb->u.iaaddr, nic->netdev->dev_addr, ETH_ALEN);
        return 0;
}

static int e100_dump(struct nic *nic, struct cb *cb, struct sk_buff *skb)
{
        cb->command = cpu_to_le16(cb_dump);
        cb->u.dump_buffer_addr = cpu_to_le32(nic->dma_addr +
                offsetof(struct mem, dump_buf));
        return 0;
}

static int e100_phy_check_without_mii(struct nic *nic)
{
        u8 phy_type;
        int without_mii;

        phy_type = (le16_to_cpu(nic->eeprom[eeprom_phy_iface]) >> 8) & 0x0f;

        switch (phy_type) {
        case NoSuchPhy: /* Non-MII PHY; UNTESTED! */
        case I82503: /* Non-MII PHY; UNTESTED! */
        case S80C24: /* Non-MII PHY; tested and working */
                /* paragraph from the FreeBSD driver, "FXP_PHY_80C24":
                 * The Seeq 80c24 AutoDUPLEX(tm) Ethernet Interface Adapter
                 * doesn't have a programming interface of any sort.  The
                 * media is sensed automatically based on how the link partner
                 * is configured.  This is, in essence, manual configuration.
                 */
                netif_info(nic, probe, nic->netdev,
                           "found MII-less i82503 or 80c24 or other PHY\n");

                nic->mdio_ctrl = mdio_ctrl_phy_mii_emulated;
                nic->mii.phy_id = 0; /* is this ok for an MII-less PHY? */

                /* these might be needed for certain MII-less cards...
                 * nic->flags |= ich;
                 * nic->flags |= ich_10h_workaround; */

                without_mii = 1;
                break;
        default:
                without_mii = 0;
                break;
        }
        return without_mii;
}

#define NCONFIG_AUTO_SWITCH     0x0080
#define MII_NSC_CONG            MII_RESV1
#define NSC_CONG_ENABLE         0x0100
#define NSC_CONG_TXREADY        0x0400
#define ADVERTISE_FC_SUPPORTED  0x0400
static int e100_phy_init(struct nic *nic)
{
        struct net_device *netdev = nic->netdev;
        u32 addr;
        u16 bmcr, stat, id_lo, id_hi, cong;

        /* Discover phy addr by searching addrs in order {1,0,2,..., 31} */
        for (addr = 0; addr < 32; addr++) {
                nic->mii.phy_id = (addr == 0) ? 1 : (addr == 1) ? 0 : addr;
                bmcr = mdio_read(netdev, nic->mii.phy_id, MII_BMCR);
                stat = mdio_read(netdev, nic->mii.phy_id, MII_BMSR);
                stat = mdio_read(netdev, nic->mii.phy_id, MII_BMSR);
                if (!((bmcr == 0xFFFF) || ((stat == 0) && (bmcr == 0))))
                        break;
        }
        if (addr == 32) {
                /* uhoh, no PHY detected: check whether we seem to be some
                 * weird, rare variant which is *known* to not have any MII.
                 * But do this AFTER MII checking only, since this does
                 * lookup of EEPROM values which may easily be unreliable. */
                if (e100_phy_check_without_mii(nic))
                        return 0; /* simply return and hope for the best */
                else {
                        /* for unknown cases log a fatal error */
                        netif_err(nic, hw, nic->netdev,
                                  "Failed to locate any known PHY, aborting\n");
                        return -EAGAIN;
                }
        } else
                netif_printk(nic, hw, KERN_DEBUG, nic->netdev,
                             "phy_addr = %d\n", nic->mii.phy_id);

        /* Get phy ID */
        id_lo = mdio_read(netdev, nic->mii.phy_id, MII_PHYSID1);
        id_hi = mdio_read(netdev, nic->mii.phy_id, MII_PHYSID2);
        nic->phy = (u32)id_hi << 16 | (u32)id_lo;
        netif_printk(nic, hw, KERN_DEBUG, nic->netdev,
                     "phy ID = 0x%08X\n", nic->phy);

        /* Select the phy and isolate the rest */
        for (addr = 0; addr < 32; addr++) {
                if (addr != nic->mii.phy_id) {
                        mdio_write(netdev, addr, MII_BMCR, BMCR_ISOLATE);
                } else if (nic->phy != phy_82552_v) {
                        bmcr = mdio_read(netdev, addr, MII_BMCR);
                        mdio_write(netdev, addr, MII_BMCR,
                                bmcr & ~BMCR_ISOLATE);
                }
        }
        /*
         * Workaround for 82552:
         * Clear the ISOLATE bit on selected phy_id last (mirrored on all
         * other phy_id's) using bmcr value from addr discovery loop above.
         */
        if (nic->phy == phy_82552_v)
                mdio_write(netdev, nic->mii.phy_id, MII_BMCR,
                        bmcr & ~BMCR_ISOLATE);

        /* Handle National tx phys */
#define NCS_PHY_MODEL_MASK      0xFFF0FFFF
        if ((nic->phy & NCS_PHY_MODEL_MASK) == phy_nsc_tx) {
                /* Disable congestion control */
                cong = mdio_read(netdev, nic->mii.phy_id, MII_NSC_CONG);
                cong |= NSC_CONG_TXREADY;
                cong &= ~NSC_CONG_ENABLE;
                mdio_write(netdev, nic->mii.phy_id, MII_NSC_CONG, cong);
        }

        if (nic->phy == phy_82552_v) {
                u16 advert = mdio_read(netdev, nic->mii.phy_id, MII_ADVERTISE);

                /* assign special tweaked mdio_ctrl() function */
                nic->mdio_ctrl = mdio_ctrl_phy_82552_v;

                /* Workaround Si not advertising flow-control during autoneg */
                advert |= ADVERTISE_PAUSE_CAP | ADVERTISE_PAUSE_ASYM;
                mdio_write(netdev, nic->mii.phy_id, MII_ADVERTISE, advert);

                /* Reset for the above changes to take effect */
                bmcr = mdio_read(netdev, nic->mii.phy_id, MII_BMCR);
                bmcr |= BMCR_RESET;
                mdio_write(netdev, nic->mii.phy_id, MII_BMCR, bmcr);
        } else if ((nic->mac >= mac_82550_D102) || ((nic->flags & ich) &&
           (mdio_read(netdev, nic->mii.phy_id, MII_TPISTATUS) & 0x8000) &&
           (le16_to_cpu(nic->eeprom[eeprom_cnfg_mdix]) & eeprom_mdix_enabled))) {
                /* enable/disable MDI/MDI-X auto-switching. */
                mdio_write(netdev, nic->mii.phy_id, MII_NCONFIG,
                                nic->mii.force_media ? 0 : NCONFIG_AUTO_SWITCH);
        }

        return 0;
}

static int e100_hw_init(struct nic *nic)
{
        int err = 0;

        e100_hw_reset(nic);

        netif_err(nic, hw, nic->netdev, "e100_hw_init\n");
        if ((err = e100_self_test(nic)))
                return err;

        if ((err = e100_phy_init(nic)))
                return err;
        if ((err = e100_exec_cmd(nic, cuc_load_base, 0)))
                return err;
        if ((err = e100_exec_cmd(nic, ruc_load_base, 0)))
                return err;
        if ((err = e100_load_ucode_wait(nic)))
                return err;
        if ((err = e100_exec_cb(nic, NULL, e100_configure)))
                return err;
        if ((err = e100_exec_cb(nic, NULL, e100_setup_iaaddr)))
                return err;
        if ((err = e100_exec_cmd(nic, cuc_dump_addr,
                nic->dma_addr + offsetof(struct mem, stats))))
                return err;
        if ((err = e100_exec_cmd(nic, cuc_dump_reset, 0)))
                return err;

        e100_disable_irq(nic);

        return 0;
}

static int e100_multi(struct nic *nic, struct cb *cb, struct sk_buff *skb)
{
        struct net_device *netdev = nic->netdev;
        struct netdev_hw_addr *ha;
        u16 i, count = min(netdev_mc_count(netdev), E100_MAX_MULTICAST_ADDRS);

        cb->command = cpu_to_le16(cb_multi);
        cb->u.multi.count = cpu_to_le16(count * ETH_ALEN);
        i = 0;
        netdev_for_each_mc_addr(ha, netdev) {
                if (i == count)
                        break;
                memcpy(&cb->u.multi.addr[i++ * ETH_ALEN], &ha->addr,
                        ETH_ALEN);
        }
        return 0;
}

static void e100_set_multicast_list(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);

        netif_printk(nic, hw, KERN_DEBUG, nic->netdev,
                     "mc_count=%d, flags=0x%04X\n",
                     netdev_mc_count(netdev), netdev->flags);

        if (netdev->flags & IFF_PROMISC)
                nic->flags |= promiscuous;
        else
                nic->flags &= ~promiscuous;

        if (netdev->flags & IFF_ALLMULTI ||
                netdev_mc_count(netdev) > E100_MAX_MULTICAST_ADDRS)
                nic->flags |= multicast_all;
        else
                nic->flags &= ~multicast_all;

        e100_exec_cb(nic, NULL, e100_configure);
        e100_exec_cb(nic, NULL, e100_multi);
}

static void e100_update_stats(struct nic *nic)
{
        struct net_device *dev = nic->netdev;
        struct net_device_stats *ns = &dev->stats;
        struct stats *s = &nic->mem->stats;
        __le32 *complete = (nic->mac < mac_82558_D101_A4) ? &s->fc_xmt_pause :
                (nic->mac < mac_82559_D101M) ? (__le32 *)&s->xmt_tco_frames :
                &s->complete;

        /* Device's stats reporting may take several microseconds to
         * complete, so we're always waiting for results of the
         * previous command. */

        if (*complete == cpu_to_le32(cuc_dump_reset_complete)) {
                *complete = 0;
                nic->tx_frames = le32_to_cpu(s->tx_good_frames);
                nic->tx_collisions = le32_to_cpu(s->tx_total_collisions);
                ns->tx_aborted_errors += le32_to_cpu(s->tx_max_collisions);
                ns->tx_window_errors += le32_to_cpu(s->tx_late_collisions);
                ns->tx_carrier_errors += le32_to_cpu(s->tx_lost_crs);
                ns->tx_fifo_errors += le32_to_cpu(s->tx_underruns);
                ns->collisions += nic->tx_collisions;
                ns->tx_errors += le32_to_cpu(s->tx_max_collisions) +
                        le32_to_cpu(s->tx_lost_crs);
                nic->rx_short_frame_errors +=
                        le32_to_cpu(s->rx_short_frame_errors);
                ns->rx_length_errors = nic->rx_short_frame_errors +
                        nic->rx_over_length_errors;
                ns->rx_crc_errors += le32_to_cpu(s->rx_crc_errors);
                ns->rx_frame_errors += le32_to_cpu(s->rx_alignment_errors);
                ns->rx_over_errors += le32_to_cpu(s->rx_overrun_errors);
                ns->rx_fifo_errors += le32_to_cpu(s->rx_overrun_errors);
                ns->rx_missed_errors += le32_to_cpu(s->rx_resource_errors);
                ns->rx_errors += le32_to_cpu(s->rx_crc_errors) +
                        le32_to_cpu(s->rx_alignment_errors) +
                        le32_to_cpu(s->rx_short_frame_errors) +
                        le32_to_cpu(s->rx_cdt_errors);
                nic->tx_deferred += le32_to_cpu(s->tx_deferred);
                nic->tx_single_collisions +=
                        le32_to_cpu(s->tx_single_collisions);
                nic->tx_multiple_collisions +=
                        le32_to_cpu(s->tx_multiple_collisions);
                if (nic->mac >= mac_82558_D101_A4) {
                        nic->tx_fc_pause += le32_to_cpu(s->fc_xmt_pause);
                        nic->rx_fc_pause += le32_to_cpu(s->fc_rcv_pause);
                        nic->rx_fc_unsupported +=
                                le32_to_cpu(s->fc_rcv_unsupported);
                        if (nic->mac >= mac_82559_D101M) {
                                nic->tx_tco_frames +=
                                        le16_to_cpu(s->xmt_tco_frames);
                                nic->rx_tco_frames +=
                                        le16_to_cpu(s->rcv_tco_frames);
                        }
                }
        }


        if (e100_exec_cmd(nic, cuc_dump_reset, 0))
                netif_printk(nic, tx_err, KERN_DEBUG, nic->netdev,
                             "exec cuc_dump_reset failed\n");
}

static void e100_adjust_adaptive_ifs(struct nic *nic, int speed, int duplex)
{
        /* Adjust inter-frame-spacing (IFS) between two transmits if
         * we're getting collisions on a half-duplex connection. */

        if (duplex == DUPLEX_HALF) {
                u32 prev = nic->adaptive_ifs;
                u32 min_frames = (speed == SPEED_100) ? 1000 : 100;

                if ((nic->tx_frames / 32 < nic->tx_collisions) &&
                   (nic->tx_frames > min_frames)) {
                        if (nic->adaptive_ifs < 60)
                                nic->adaptive_ifs += 5;
                } else if (nic->tx_frames < min_frames) {
                        if (nic->adaptive_ifs >= 5)
                                nic->adaptive_ifs -= 5;
                }
                if (nic->adaptive_ifs != prev)
                        e100_exec_cb(nic, NULL, e100_configure);
        }
}

static void e100_watchdog(struct timer_list *t)
{
        struct nic *nic = from_timer(nic, t, watchdog);
        struct ethtool_cmd cmd = { .cmd = ETHTOOL_GSET };
        u32 speed;

        netif_printk(nic, timer, KERN_DEBUG, nic->netdev,
                     "right now = %ld\n", jiffies);

        /* mii library handles link maintenance tasks */

        mii_ethtool_gset(&nic->mii, &cmd);
        speed = ethtool_cmd_speed(&cmd);

        if (mii_link_ok(&nic->mii) && !netif_carrier_ok(nic->netdev)) {
                netdev_info(nic->netdev, "NIC Link is Up %u Mbps %s Duplex\n",
                            speed == SPEED_100 ? 100 : 10,
                            cmd.duplex == DUPLEX_FULL ? "Full" : "Half");
        } else if (!mii_link_ok(&nic->mii) && netif_carrier_ok(nic->netdev)) {
                netdev_info(nic->netdev, "NIC Link is Down\n");
        }

        mii_check_link(&nic->mii);

        /* Software generated interrupt to recover from (rare) Rx
         * allocation failure.
         * Unfortunately have to use a spinlock to not re-enable interrupts
         * accidentally, due to hardware that shares a register between the
         * interrupt mask bit and the SW Interrupt generation bit */
        spin_lock_irq(&nic->cmd_lock);
        iowrite8(ioread8(&nic->csr->scb.cmd_hi) | irq_sw_gen,&nic->csr->scb.cmd_hi);
        e100_write_flush(nic);
        spin_unlock_irq(&nic->cmd_lock);

        e100_update_stats(nic);
        e100_adjust_adaptive_ifs(nic, speed, cmd.duplex);

        if (nic->mac <= mac_82557_D100_C)
                /* Issue a multicast command to workaround a 557 lock up */
                e100_set_multicast_list(nic->netdev);

        if (nic->flags & ich && speed == SPEED_10 && cmd.duplex == DUPLEX_HALF)
                /* Need SW workaround for ICH[x] 10Mbps/half duplex Tx hang. */
                nic->flags |= ich_10h_workaround;
        else
                nic->flags &= ~ich_10h_workaround;

        mod_timer(&nic->watchdog,
                  round_jiffies(jiffies + E100_WATCHDOG_PERIOD));
}

static int e100_xmit_prepare(struct nic *nic, struct cb *cb,
        struct sk_buff *skb)
{
        dma_addr_t dma_addr;
        cb->command = nic->tx_command;

        dma_addr = dma_map_single(&nic->pdev->dev, skb->data, skb->len,
                                  DMA_TO_DEVICE);
        /* If we can't map the skb, have the upper layer try later */
        if (dma_mapping_error(&nic->pdev->dev, dma_addr))
                return -ENOMEM;

        /*
         * Use the last 4 bytes of the SKB payload packet as the CRC, used for
         * testing, ie sending frames with bad CRC.
         */
        if (unlikely(skb->no_fcs))
                cb->command |= cpu_to_le16(cb_tx_nc);
        else
                cb->command &= ~cpu_to_le16(cb_tx_nc);

        /* interrupt every 16 packets regardless of delay */
        if ((nic->cbs_avail & ~15) == nic->cbs_avail)
                cb->command |= cpu_to_le16(cb_i);
        cb->u.tcb.tbd_array = cb->dma_addr + offsetof(struct cb, u.tcb.tbd);
        cb->u.tcb.tcb_byte_count = 0;
        cb->u.tcb.threshold = nic->tx_threshold;
        cb->u.tcb.tbd_count = 1;
        cb->u.tcb.tbd.buf_addr = cpu_to_le32(dma_addr);
        cb->u.tcb.tbd.size = cpu_to_le16(skb->len);
        skb_tx_timestamp(skb);
        return 0;
}

static netdev_tx_t e100_xmit_frame(struct sk_buff *skb,
                                   struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);
        int err;

        if (nic->flags & ich_10h_workaround) {
                /* SW workaround for ICH[x] 10Mbps/half duplex Tx hang.
                   Issue a NOP command followed by a 1us delay before
                   issuing the Tx command. */
                if (e100_exec_cmd(nic, cuc_nop, 0))
                        netif_printk(nic, tx_err, KERN_DEBUG, nic->netdev,
                                     "exec cuc_nop failed\n");
                udelay(1);
        }

        err = e100_exec_cb(nic, skb, e100_xmit_prepare);

        switch (err) {
        case -ENOSPC:
                /* We queued the skb, but now we're out of space. */
                netif_printk(nic, tx_err, KERN_DEBUG, nic->netdev,
                             "No space for CB\n");
                netif_stop_queue(netdev);
                break;
        case -ENOMEM:
                /* This is a hard error - log it. */
                netif_printk(nic, tx_err, KERN_DEBUG, nic->netdev,
                             "Out of Tx resources, returning skb\n");
                netif_stop_queue(netdev);
                return NETDEV_TX_BUSY;
        }

        return NETDEV_TX_OK;
}

static int e100_tx_clean(struct nic *nic)
{
        struct net_device *dev = nic->netdev;
        struct cb *cb;
        int tx_cleaned = 0;

        spin_lock(&nic->cb_lock);

        /* Clean CBs marked complete */
        for (cb = nic->cb_to_clean;
            cb->status & cpu_to_le16(cb_complete);
            cb = nic->cb_to_clean = cb->next) {
                dma_rmb(); /* read skb after status */
                netif_printk(nic, tx_done, KERN_DEBUG, nic->netdev,
                             "cb[%d]->status = 0x%04X\n",
                             (int)(((void*)cb - (void*)nic->cbs)/sizeof(struct cb)),
                             cb->status);

                if (likely(cb->skb != NULL)) {
                        dev->stats.tx_packets++;
                        dev->stats.tx_bytes += cb->skb->len;

                        dma_unmap_single(&nic->pdev->dev,
                                         le32_to_cpu(cb->u.tcb.tbd.buf_addr),
                                         le16_to_cpu(cb->u.tcb.tbd.size),
                                         DMA_TO_DEVICE);
                        dev_kfree_skb_any(cb->skb);
                        cb->skb = NULL;
                        tx_cleaned = 1;
                }
                cb->status = 0;
                nic->cbs_avail++;
        }

        spin_unlock(&nic->cb_lock);

        /* Recover from running out of Tx resources in xmit_frame */
        if (unlikely(tx_cleaned && netif_queue_stopped(nic->netdev)))
                netif_wake_queue(nic->netdev);

        return tx_cleaned;
}

static void e100_clean_cbs(struct nic *nic)
{
        if (nic->cbs) {
                while (nic->cbs_avail != nic->params.cbs.count) {
                        struct cb *cb = nic->cb_to_clean;
                        if (cb->skb) {
                                dma_unmap_single(&nic->pdev->dev,
                                                 le32_to_cpu(cb->u.tcb.tbd.buf_addr),
                                                 le16_to_cpu(cb->u.tcb.tbd.size),
                                                 DMA_TO_DEVICE);
                                dev_kfree_skb(cb->skb);
                        }
                        nic->cb_to_clean = nic->cb_to_clean->next;
                        nic->cbs_avail++;
                }
                dma_pool_free(nic->cbs_pool, nic->cbs, nic->cbs_dma_addr);
                nic->cbs = NULL;
                nic->cbs_avail = 0;
        }
        nic->cuc_cmd = cuc_start;
        nic->cb_to_use = nic->cb_to_send = nic->cb_to_clean =
                nic->cbs;
}

static int e100_alloc_cbs(struct nic *nic)
{
        struct cb *cb;
        unsigned int i, count = nic->params.cbs.count;

        nic->cuc_cmd = cuc_start;
        nic->cb_to_use = nic->cb_to_send = nic->cb_to_clean = NULL;
        nic->cbs_avail = 0;

        nic->cbs = dma_pool_zalloc(nic->cbs_pool, GFP_KERNEL,
                                   &nic->cbs_dma_addr);
        if (!nic->cbs)
                return -ENOMEM;

        for (cb = nic->cbs, i = 0; i < count; cb++, i++) {
                cb->next = (i + 1 < count) ? cb + 1 : nic->cbs;
                cb->prev = (i == 0) ? nic->cbs + count - 1 : cb - 1;

                cb->dma_addr = nic->cbs_dma_addr + i * sizeof(struct cb);
                cb->link = cpu_to_le32(nic->cbs_dma_addr +
                        ((i+1) % count) * sizeof(struct cb));
        }

        nic->cb_to_use = nic->cb_to_send = nic->cb_to_clean = nic->cbs;
        nic->cbs_avail = count;

        return 0;
}

static inline void e100_start_receiver(struct nic *nic, struct rx *rx)
{
        if (!nic->rxs) return;
        if (RU_SUSPENDED != nic->ru_running) return;

        /* handle init time starts */
        if (!rx) rx = nic->rxs;

        /* (Re)start RU if suspended or idle and RFA is non-NULL */
        if (rx->skb) {
                e100_exec_cmd(nic, ruc_start, rx->dma_addr);
                nic->ru_running = RU_RUNNING;
        }
}

#define RFD_BUF_LEN (sizeof(struct rfd) + VLAN_ETH_FRAME_LEN + ETH_FCS_LEN)
static int e100_rx_alloc_skb(struct nic *nic, struct rx *rx)
{
        if (!(rx->skb = netdev_alloc_skb_ip_align(nic->netdev, RFD_BUF_LEN)))
                return -ENOMEM;

        /* Init, and map the RFD. */
        skb_copy_to_linear_data(rx->skb, &nic->blank_rfd, sizeof(struct rfd));
        rx->dma_addr = dma_map_single(&nic->pdev->dev, rx->skb->data,
                                      RFD_BUF_LEN, DMA_BIDIRECTIONAL);

        if (dma_mapping_error(&nic->pdev->dev, rx->dma_addr)) {
                dev_kfree_skb_any(rx->skb);
                rx->skb = NULL;
                rx->dma_addr = 0;
                return -ENOMEM;
        }

        /* Link the RFD to end of RFA by linking previous RFD to
         * this one.  We are safe to touch the previous RFD because
         * it is protected by the before last buffer's el bit being set */
        if (rx->prev->skb) {
                struct rfd *prev_rfd = (struct rfd *)rx->prev->skb->data;
                put_unaligned_le32(rx->dma_addr, &prev_rfd->link);
                dma_sync_single_for_device(&nic->pdev->dev,
                                           rx->prev->dma_addr,
                                           sizeof(struct rfd),
                                           DMA_BIDIRECTIONAL);
        }

        return 0;
}

static int e100_rx_indicate(struct nic *nic, struct rx *rx,
        unsigned int *work_done, unsigned int work_to_do)
{
        struct net_device *dev = nic->netdev;
        struct sk_buff *skb = rx->skb;
        struct rfd *rfd = (struct rfd *)skb->data;
        u16 rfd_status, actual_size;
        u16 fcs_pad = 0;

        if (unlikely(work_done && *work_done >= work_to_do))
                return -EAGAIN;

        /* Need to sync before taking a peek at cb_complete bit */
        dma_sync_single_for_cpu(&nic->pdev->dev, rx->dma_addr,
                                sizeof(struct rfd), DMA_BIDIRECTIONAL);
        rfd_status = le16_to_cpu(rfd->status);

        netif_printk(nic, rx_status, KERN_DEBUG, nic->netdev,
                     "status=0x%04X\n", rfd_status);
        dma_rmb(); /* read size after status bit */

        /* If data isn't ready, nothing to indicate */
        if (unlikely(!(rfd_status & cb_complete))) {
                /* If the next buffer has the el bit, but we think the receiver
                 * is still running, check to see if it really stopped while
                 * we had interrupts off.
                 * This allows for a fast restart without re-enabling
                 * interrupts */
                if ((le16_to_cpu(rfd->command) & cb_el) &&
                    (RU_RUNNING == nic->ru_running))

                        if (ioread8(&nic->csr->scb.status) & rus_no_res)
                                nic->ru_running = RU_SUSPENDED;
                dma_sync_single_for_device(&nic->pdev->dev, rx->dma_addr,
                                           sizeof(struct rfd),
                                           DMA_FROM_DEVICE);
                return -ENODATA;
        }

        /* Get actual data size */
        if (unlikely(dev->features & NETIF_F_RXFCS))
                fcs_pad = 4;
        actual_size = le16_to_cpu(rfd->actual_size) & 0x3FFF;
        if (unlikely(actual_size > RFD_BUF_LEN - sizeof(struct rfd)))
                actual_size = RFD_BUF_LEN - sizeof(struct rfd);

        /* Get data */
        dma_unmap_single(&nic->pdev->dev, rx->dma_addr, RFD_BUF_LEN,
                         DMA_BIDIRECTIONAL);

        /* If this buffer has the el bit, but we think the receiver
         * is still running, check to see if it really stopped while
         * we had interrupts off.
         * This allows for a fast restart without re-enabling interrupts.
         * This can happen when the RU sees the size change but also sees
         * the el bit set. */
        if ((le16_to_cpu(rfd->command) & cb_el) &&
            (RU_RUNNING == nic->ru_running)) {

            if (ioread8(&nic->csr->scb.status) & rus_no_res)
                nic->ru_running = RU_SUSPENDED;
        }

        /* Pull off the RFD and put the actual data (minus eth hdr) */
        skb_reserve(skb, sizeof(struct rfd));
        skb_put(skb, actual_size);
        skb->protocol = eth_type_trans(skb, nic->netdev);

        /* If we are receiving all frames, then don't bother
         * checking for errors.
         */
        if (unlikely(dev->features & NETIF_F_RXALL)) {
                if (actual_size > ETH_DATA_LEN + VLAN_ETH_HLEN + fcs_pad)
                        /* Received oversized frame, but keep it. */
                        nic->rx_over_length_errors++;
                goto process_skb;
        }

        if (unlikely(!(rfd_status & cb_ok))) {
                /* Don't indicate if hardware indicates errors */
                dev_kfree_skb_any(skb);
        } else if (actual_size > ETH_DATA_LEN + VLAN_ETH_HLEN + fcs_pad) {
                /* Don't indicate oversized frames */
                nic->rx_over_length_errors++;
                dev_kfree_skb_any(skb);
        } else {
process_skb:
                dev->stats.rx_packets++;
                dev->stats.rx_bytes += (actual_size - fcs_pad);
                netif_receive_skb(skb);
                if (work_done)
                        (*work_done)++;
        }

        rx->skb = NULL;

        return 0;
}

static void e100_rx_clean(struct nic *nic, unsigned int *work_done,
        unsigned int work_to_do)
{
        struct rx *rx;
        int restart_required = 0, err = 0;
        struct rx *old_before_last_rx, *new_before_last_rx;
        struct rfd *old_before_last_rfd, *new_before_last_rfd;

        /* Indicate newly arrived packets */
        for (rx = nic->rx_to_clean; rx->skb; rx = nic->rx_to_clean = rx->next) {
                err = e100_rx_indicate(nic, rx, work_done, work_to_do);
                /* Hit quota or no more to clean */
                if (-EAGAIN == err || -ENODATA == err)
                        break;
        }


        /* On EAGAIN, hit quota so have more work to do, restart once
         * cleanup is complete.
         * Else, are we already rnr? then pay attention!!! this ensures that
         * the state machine progression never allows a start with a
         * partially cleaned list, avoiding a race between hardware
         * and rx_to_clean when in NAPI mode */
        if (-EAGAIN != err && RU_SUSPENDED == nic->ru_running)
                restart_required = 1;

        old_before_last_rx = nic->rx_to_use->prev->prev;
        old_before_last_rfd = (struct rfd *)old_before_last_rx->skb->data;

        /* Alloc new skbs to refill list */
        for (rx = nic->rx_to_use; !rx->skb; rx = nic->rx_to_use = rx->next) {
                if (unlikely(e100_rx_alloc_skb(nic, rx)))
                        break; /* Better luck next time (see watchdog) */
        }

        new_before_last_rx = nic->rx_to_use->prev->prev;
        if (new_before_last_rx != old_before_last_rx) {
                /* Set the el-bit on the buffer that is before the last buffer.
                 * This lets us update the next pointer on the last buffer
                 * without worrying about hardware touching it.
                 * We set the size to 0 to prevent hardware from touching this
                 * buffer.
                 * When the hardware hits the before last buffer with el-bit
                 * and size of 0, it will RNR interrupt, the RUS will go into
                 * the No Resources state.  It will not complete nor write to
                 * this buffer. */
                new_before_last_rfd =
                        (struct rfd *)new_before_last_rx->skb->data;
                new_before_last_rfd->size = 0;
                new_before_last_rfd->command |= cpu_to_le16(cb_el);
                dma_sync_single_for_device(&nic->pdev->dev,
                                           new_before_last_rx->dma_addr,
                                           sizeof(struct rfd),
                                           DMA_BIDIRECTIONAL);

                /* Now that we have a new stopping point, we can clear the old
                 * stopping point.  We must sync twice to get the proper
                 * ordering on the hardware side of things. */
                old_before_last_rfd->command &= ~cpu_to_le16(cb_el);
                dma_sync_single_for_device(&nic->pdev->dev,
                                           old_before_last_rx->dma_addr,
                                           sizeof(struct rfd),
                                           DMA_BIDIRECTIONAL);
                old_before_last_rfd->size = cpu_to_le16(VLAN_ETH_FRAME_LEN
                                                        + ETH_FCS_LEN);
                dma_sync_single_for_device(&nic->pdev->dev,
                                           old_before_last_rx->dma_addr,
                                           sizeof(struct rfd),
                                           DMA_BIDIRECTIONAL);
        }

        if (restart_required) {
                // ack the rnr?
                iowrite8(stat_ack_rnr, &nic->csr->scb.stat_ack);
                e100_start_receiver(nic, nic->rx_to_clean);
                if (work_done)
                        (*work_done)++;
        }
}

static void e100_rx_clean_list(struct nic *nic)
{
        struct rx *rx;
        unsigned int i, count = nic->params.rfds.count;

        nic->ru_running = RU_UNINITIALIZED;

        if (nic->rxs) {
                for (rx = nic->rxs, i = 0; i < count; rx++, i++) {
                        if (rx->skb) {
                                dma_unmap_single(&nic->pdev->dev,
                                                 rx->dma_addr, RFD_BUF_LEN,
                                                 DMA_BIDIRECTIONAL);
                                dev_kfree_skb(rx->skb);
                        }
                }
                kfree(nic->rxs);
                nic->rxs = NULL;
        }

        nic->rx_to_use = nic->rx_to_clean = NULL;
}

static int e100_rx_alloc_list(struct nic *nic)
{
        struct rx *rx;
        unsigned int i, count = nic->params.rfds.count;
        struct rfd *before_last;

        nic->rx_to_use = nic->rx_to_clean = NULL;
        nic->ru_running = RU_UNINITIALIZED;

        if (!(nic->rxs = kcalloc(count, sizeof(struct rx), GFP_KERNEL)))
                return -ENOMEM;

        for (rx = nic->rxs, i = 0; i < count; rx++, i++) {
                rx->next = (i + 1 < count) ? rx + 1 : nic->rxs;
                rx->prev = (i == 0) ? nic->rxs + count - 1 : rx - 1;
                if (e100_rx_alloc_skb(nic, rx)) {
                        e100_rx_clean_list(nic);
                        return -ENOMEM;
                }
        }
        /* Set the el-bit on the buffer that is before the last buffer.
         * This lets us update the next pointer on the last buffer without
         * worrying about hardware touching it.
         * We set the size to 0 to prevent hardware from touching this buffer.
         * When the hardware hits the before last buffer with el-bit and size
         * of 0, it will RNR interrupt, the RU will go into the No Resources
         * state.  It will not complete nor write to this buffer. */
        rx = nic->rxs->prev->prev;
        before_last = (struct rfd *)rx->skb->data;
        before_last->command |= cpu_to_le16(cb_el);
        before_last->size = 0;
        dma_sync_single_for_device(&nic->pdev->dev, rx->dma_addr,
                                   sizeof(struct rfd), DMA_BIDIRECTIONAL);

        nic->rx_to_use = nic->rx_to_clean = nic->rxs;
        nic->ru_running = RU_SUSPENDED;

        return 0;
}

static irqreturn_t e100_intr(int irq, void *dev_id)
{
        struct net_device *netdev = dev_id;
        struct nic *nic = netdev_priv(netdev);
        u8 stat_ack = ioread8(&nic->csr->scb.stat_ack);

        netif_printk(nic, intr, KERN_DEBUG, nic->netdev,
                     "stat_ack = 0x%02X\n", stat_ack);

        if (stat_ack == stat_ack_not_ours ||    /* Not our interrupt */
           stat_ack == stat_ack_not_present)    /* Hardware is ejected */
                return IRQ_NONE;

        /* Ack interrupt(s) */
        iowrite8(stat_ack, &nic->csr->scb.stat_ack);

        /* We hit Receive No Resource (RNR); restart RU after cleaning */
        if (stat_ack & stat_ack_rnr)
                nic->ru_running = RU_SUSPENDED;

        if (likely(napi_schedule_prep(&nic->napi))) {
                e100_disable_irq(nic);
                __napi_schedule(&nic->napi);
        }

        return IRQ_HANDLED;
}

static int e100_poll(struct napi_struct *napi, int budget)
{
        struct nic *nic = container_of(napi, struct nic, napi);
        unsigned int work_done = 0;

        e100_rx_clean(nic, &work_done, budget);
        e100_tx_clean(nic);

        /* If budget fully consumed, continue polling */
        if (work_done == budget)
                return budget;

        /* only re-enable interrupt if stack agrees polling is really done */
        if (likely(napi_complete_done(napi, work_done)))
                e100_enable_irq(nic);

        return work_done;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void e100_netpoll(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);

        e100_disable_irq(nic);
        e100_intr(nic->pdev->irq, netdev);
        e100_tx_clean(nic);
        e100_enable_irq(nic);
}
#endif

static int e100_set_mac_address(struct net_device *netdev, void *p)
{
        struct nic *nic = netdev_priv(netdev);
        struct sockaddr *addr = p;

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

        memcpy(netdev->dev_addr, addr->sa_data, netdev->addr_len);
        e100_exec_cb(nic, NULL, e100_setup_iaaddr);

        return 0;
}

static int e100_asf(struct nic *nic)
{
        /* ASF can be enabled from eeprom */
        return (nic->pdev->device >= 0x1050) && (nic->pdev->device <= 0x1057) &&
           (le16_to_cpu(nic->eeprom[eeprom_config_asf]) & eeprom_asf) &&
           !(le16_to_cpu(nic->eeprom[eeprom_config_asf]) & eeprom_gcl) &&
           ((le16_to_cpu(nic->eeprom[eeprom_smbus_addr]) & 0xFF) != 0xFE);
}

static int e100_up(struct nic *nic)
{
        int err;

        if ((err = e100_rx_alloc_list(nic)))
                return err;
        if ((err = e100_alloc_cbs(nic)))
                goto err_rx_clean_list;
        if ((err = e100_hw_init(nic)))
                goto err_clean_cbs;
        e100_set_multicast_list(nic->netdev);
        e100_start_receiver(nic, NULL);
        mod_timer(&nic->watchdog, jiffies);
        if ((err = request_irq(nic->pdev->irq, e100_intr, IRQF_SHARED,
                nic->netdev->name, nic->netdev)))
                goto err_no_irq;
        netif_wake_queue(nic->netdev);
        napi_enable(&nic->napi);
        /* enable ints _after_ enabling poll, preventing a race between
         * disable ints+schedule */
        e100_enable_irq(nic);
        return 0;

err_no_irq:
        del_timer_sync(&nic->watchdog);
err_clean_cbs:
        e100_clean_cbs(nic);
err_rx_clean_list:
        e100_rx_clean_list(nic);
        return err;
}

static void e100_down(struct nic *nic)
{
        /* wait here for poll to complete */
        napi_disable(&nic->napi);
        netif_stop_queue(nic->netdev);
        e100_hw_reset(nic);
        free_irq(nic->pdev->irq, nic->netdev);
        del_timer_sync(&nic->watchdog);
        netif_carrier_off(nic->netdev);
        e100_clean_cbs(nic);
        e100_rx_clean_list(nic);
}

static void e100_tx_timeout(struct net_device *netdev, unsigned int txqueue)
{
        struct nic *nic = netdev_priv(netdev);

        /* Reset outside of interrupt context, to avoid request_irq
         * in interrupt context */
        schedule_work(&nic->tx_timeout_task);
}

static void e100_tx_timeout_task(struct work_struct *work)
{
        struct nic *nic = container_of(work, struct nic, tx_timeout_task);
        struct net_device *netdev = nic->netdev;

        netif_printk(nic, tx_err, KERN_DEBUG, nic->netdev,
                     "scb.status=0x%02X\n", ioread8(&nic->csr->scb.status));

        rtnl_lock();
        if (netif_running(netdev)) {
                e100_down(netdev_priv(netdev));
                e100_up(netdev_priv(netdev));
        }
        rtnl_unlock();
}

static int e100_loopback_test(struct nic *nic, enum loopback loopback_mode)
{
        int err;
        struct sk_buff *skb;

        /* Use driver resources to perform internal MAC or PHY
         * loopback test.  A single packet is prepared and transmitted
         * in loopback mode, and the test passes if the received
         * packet compares byte-for-byte to the transmitted packet. */

        if ((err = e100_rx_alloc_list(nic)))
                return err;
        if ((err = e100_alloc_cbs(nic)))
                goto err_clean_rx;

        /* ICH PHY loopback is broken so do MAC loopback instead */
        if (nic->flags & ich && loopback_mode == lb_phy)
                loopback_mode = lb_mac;

        nic->loopback = loopback_mode;
        if ((err = e100_hw_init(nic)))
                goto err_loopback_none;

        if (loopback_mode == lb_phy)
                mdio_write(nic->netdev, nic->mii.phy_id, MII_BMCR,
                        BMCR_LOOPBACK);

        e100_start_receiver(nic, NULL);

        if (!(skb = netdev_alloc_skb(nic->netdev, ETH_DATA_LEN))) {
                err = -ENOMEM;
                goto err_loopback_none;
        }
        skb_put(skb, ETH_DATA_LEN);
        memset(skb->data, 0xFF, ETH_DATA_LEN);
        e100_xmit_frame(skb, nic->netdev);

        msleep(10);

        dma_sync_single_for_cpu(&nic->pdev->dev, nic->rx_to_clean->dma_addr,
                                RFD_BUF_LEN, DMA_BIDIRECTIONAL);

        if (memcmp(nic->rx_to_clean->skb->data + sizeof(struct rfd),
           skb->data, ETH_DATA_LEN))
                err = -EAGAIN;

err_loopback_none:
        mdio_write(nic->netdev, nic->mii.phy_id, MII_BMCR, 0);
        nic->loopback = lb_none;
        e100_clean_cbs(nic);
        e100_hw_reset(nic);
err_clean_rx:
        e100_rx_clean_list(nic);
        return err;
}

#define MII_LED_CONTROL 0x1B
#define E100_82552_LED_OVERRIDE 0x19
#define E100_82552_LED_ON       0x000F /* LEDTX and LED_RX both on */
#define E100_82552_LED_OFF      0x000A /* LEDTX and LED_RX both off */

static int e100_get_link_ksettings(struct net_device *netdev,
                                   struct ethtool_link_ksettings *cmd)
{
        struct nic *nic = netdev_priv(netdev);

        mii_ethtool_get_link_ksettings(&nic->mii, cmd);

        return 0;
}

static int e100_set_link_ksettings(struct net_device *netdev,
                                   const struct ethtool_link_ksettings *cmd)
{
        struct nic *nic = netdev_priv(netdev);
        int err;

        mdio_write(netdev, nic->mii.phy_id, MII_BMCR, BMCR_RESET);
        err = mii_ethtool_set_link_ksettings(&nic->mii, cmd);
        e100_exec_cb(nic, NULL, e100_configure);

        return err;
}

static void e100_get_drvinfo(struct net_device *netdev,
        struct ethtool_drvinfo *info)
{
        struct nic *nic = netdev_priv(netdev);
        strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
        strlcpy(info->bus_info, pci_name(nic->pdev),
                sizeof(info->bus_info));
}

#define E100_PHY_REGS 0x1D
static int e100_get_regs_len(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);

        /* We know the number of registers, and the size of the dump buffer.
         * Calculate the total size in bytes.
         */
        return (1 + E100_PHY_REGS) * sizeof(u32) + sizeof(nic->mem->dump_buf);
}

static void e100_get_regs(struct net_device *netdev,
        struct ethtool_regs *regs, void *p)
{
        struct nic *nic = netdev_priv(netdev);
        u32 *buff = p;
        int i;

        regs->version = (1 << 24) | nic->pdev->revision;
        buff[0] = ioread8(&nic->csr->scb.cmd_hi) << 24 |
                ioread8(&nic->csr->scb.cmd_lo) << 16 |
                ioread16(&nic->csr->scb.status);
        for (i = 0; i < E100_PHY_REGS; i++)
                /* Note that we read the registers in reverse order. This
                 * ordering is the ABI apparently used by ethtool and other
                 * applications.
                 */
                buff[1 + i] = mdio_read(netdev, nic->mii.phy_id,
                                        E100_PHY_REGS - 1 - i);
        memset(nic->mem->dump_buf, 0, sizeof(nic->mem->dump_buf));
        e100_exec_cb(nic, NULL, e100_dump);
        msleep(10);
        memcpy(&buff[1 + E100_PHY_REGS], nic->mem->dump_buf,
               sizeof(nic->mem->dump_buf));
}

static void e100_get_wol(struct net_device *netdev, struct ethtool_wolinfo *wol)
{
        struct nic *nic = netdev_priv(netdev);
        wol->supported = (nic->mac >= mac_82558_D101_A4) ?  WAKE_MAGIC : 0;
        wol->wolopts = (nic->flags & wol_magic) ? WAKE_MAGIC : 0;
}

static int e100_set_wol(struct net_device *netdev, struct ethtool_wolinfo *wol)
{
        struct nic *nic = netdev_priv(netdev);

        if ((wol->wolopts && wol->wolopts != WAKE_MAGIC) ||
            !device_can_wakeup(&nic->pdev->dev))
                return -EOPNOTSUPP;

        if (wol->wolopts)
                nic->flags |= wol_magic;
        else
                nic->flags &= ~wol_magic;

        device_set_wakeup_enable(&nic->pdev->dev, wol->wolopts);

        e100_exec_cb(nic, NULL, e100_configure);

        return 0;
}

static u32 e100_get_msglevel(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);
        return nic->msg_enable;
}

static void e100_set_msglevel(struct net_device *netdev, u32 value)
{
        struct nic *nic = netdev_priv(netdev);
        nic->msg_enable = value;
}

static int e100_nway_reset(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);
        return mii_nway_restart(&nic->mii);
}

static u32 e100_get_link(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);
        return mii_link_ok(&nic->mii);
}

static int e100_get_eeprom_len(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);
        return nic->eeprom_wc << 1;
}

#define E100_EEPROM_MAGIC       0x1234
static int e100_get_eeprom(struct net_device *netdev,
        struct ethtool_eeprom *eeprom, u8 *bytes)
{
        struct nic *nic = netdev_priv(netdev);

        eeprom->magic = E100_EEPROM_MAGIC;
        memcpy(bytes, &((u8 *)nic->eeprom)[eeprom->offset], eeprom->len);

        return 0;
}

static int e100_set_eeprom(struct net_device *netdev,
        struct ethtool_eeprom *eeprom, u8 *bytes)
{
        struct nic *nic = netdev_priv(netdev);

        if (eeprom->magic != E100_EEPROM_MAGIC)
                return -EINVAL;

        memcpy(&((u8 *)nic->eeprom)[eeprom->offset], bytes, eeprom->len);

        return e100_eeprom_save(nic, eeprom->offset >> 1,
                (eeprom->len >> 1) + 1);
}

static void e100_get_ringparam(struct net_device *netdev,
        struct ethtool_ringparam *ring)
{
        struct nic *nic = netdev_priv(netdev);
        struct param_range *rfds = &nic->params.rfds;
        struct param_range *cbs = &nic->params.cbs;

        ring->rx_max_pending = rfds->max;
        ring->tx_max_pending = cbs->max;
        ring->rx_pending = rfds->count;
        ring->tx_pending = cbs->count;
}

static int e100_set_ringparam(struct net_device *netdev,
        struct ethtool_ringparam *ring)
{
        struct nic *nic = netdev_priv(netdev);
        struct param_range *rfds = &nic->params.rfds;
        struct param_range *cbs = &nic->params.cbs;

        if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
                return -EINVAL;

        if (netif_running(netdev))
                e100_down(nic);
        rfds->count = max(ring->rx_pending, rfds->min);
        rfds->count = min(rfds->count, rfds->max);
        cbs->count = max(ring->tx_pending, cbs->min);
        cbs->count = min(cbs->count, cbs->max);
        netif_info(nic, drv, nic->netdev, "Ring Param settings: rx: %d, tx %d\n",
                   rfds->count, cbs->count);
        if (netif_running(netdev))
                e100_up(nic);

        return 0;
}

static const char e100_gstrings_test[][ETH_GSTRING_LEN] = {
        "Link test     (on/offline)",
        "Eeprom test   (on/offline)",
        "Self test        (offline)",
        "Mac loopback     (offline)",
        "Phy loopback     (offline)",
};
#define E100_TEST_LEN   ARRAY_SIZE(e100_gstrings_test)

static void e100_diag_test(struct net_device *netdev,
        struct ethtool_test *test, u64 *data)
{
        struct ethtool_cmd cmd;
        struct nic *nic = netdev_priv(netdev);
        int i;

        memset(data, 0, E100_TEST_LEN * sizeof(u64));
        data[0] = !mii_link_ok(&nic->mii);
        data[1] = e100_eeprom_load(nic);
        if (test->flags & ETH_TEST_FL_OFFLINE) {

                /* save speed, duplex & autoneg settings */
                mii_ethtool_gset(&nic->mii, &cmd);

                if (netif_running(netdev))
                        e100_down(nic);
                data[2] = e100_self_test(nic);
                data[3] = e100_loopback_test(nic, lb_mac);
                data[4] = e100_loopback_test(nic, lb_phy);

                /* restore speed, duplex & autoneg settings */
                mii_ethtool_sset(&nic->mii, &cmd);

                if (netif_running(netdev))
                        e100_up(nic);
        }
        for (i = 0; i < E100_TEST_LEN; i++)
                test->flags |= data[i] ? ETH_TEST_FL_FAILED : 0;

        msleep_interruptible(4 * 1000);
}

static int e100_set_phys_id(struct net_device *netdev,
                            enum ethtool_phys_id_state state)
{
        struct nic *nic = netdev_priv(netdev);
        enum led_state {
                led_on     = 0x01,
                led_off    = 0x04,
                led_on_559 = 0x05,
                led_on_557 = 0x07,
        };
        u16 led_reg = (nic->phy == phy_82552_v) ? E100_82552_LED_OVERRIDE :
                MII_LED_CONTROL;
        u16 leds = 0;

        switch (state) {
        case ETHTOOL_ID_ACTIVE:
                return 2;

        case ETHTOOL_ID_ON:
                leds = (nic->phy == phy_82552_v) ? E100_82552_LED_ON :
                       (nic->mac < mac_82559_D101M) ? led_on_557 : led_on_559;
                break;

        case ETHTOOL_ID_OFF:
                leds = (nic->phy == phy_82552_v) ? E100_82552_LED_OFF : led_off;
                break;

        case ETHTOOL_ID_INACTIVE:
                break;
        }

        mdio_write(netdev, nic->mii.phy_id, led_reg, leds);
        return 0;
}

static const char e100_gstrings_stats[][ETH_GSTRING_LEN] = {
        "rx_packets", "tx_packets", "rx_bytes", "tx_bytes", "rx_errors",
        "tx_errors", "rx_dropped", "tx_dropped", "multicast", "collisions",
        "rx_length_errors", "rx_over_errors", "rx_crc_errors",
        "rx_frame_errors", "rx_fifo_errors", "rx_missed_errors",
        "tx_aborted_errors", "tx_carrier_errors", "tx_fifo_errors",
        "tx_heartbeat_errors", "tx_window_errors",
        /* device-specific stats */
        "tx_deferred", "tx_single_collisions", "tx_multi_collisions",
        "tx_flow_control_pause", "rx_flow_control_pause",
        "rx_flow_control_unsupported", "tx_tco_packets", "rx_tco_packets",
        "rx_short_frame_errors", "rx_over_length_errors",
};
#define E100_NET_STATS_LEN      21
#define E100_STATS_LEN  ARRAY_SIZE(e100_gstrings_stats)

static int e100_get_sset_count(struct net_device *netdev, int sset)
{
        switch (sset) {
        case ETH_SS_TEST:
                return E100_TEST_LEN;
        case ETH_SS_STATS:
                return E100_STATS_LEN;
        default:
                return -EOPNOTSUPP;
        }
}

static void e100_get_ethtool_stats(struct net_device *netdev,
        struct ethtool_stats *stats, u64 *data)
{
        struct nic *nic = netdev_priv(netdev);
        int i;

        for (i = 0; i < E100_NET_STATS_LEN; i++)
                data[i] = ((unsigned long *)&netdev->stats)[i];

        data[i++] = nic->tx_deferred;
        data[i++] = nic->tx_single_collisions;
        data[i++] = nic->tx_multiple_collisions;
        data[i++] = nic->tx_fc_pause;
        data[i++] = nic->rx_fc_pause;
        data[i++] = nic->rx_fc_unsupported;
        data[i++] = nic->tx_tco_frames;
        data[i++] = nic->rx_tco_frames;
        data[i++] = nic->rx_short_frame_errors;
        data[i++] = nic->rx_over_length_errors;
}

static void e100_get_strings(struct net_device *netdev, u32 stringset, u8 *data)
{
        switch (stringset) {
        case ETH_SS_TEST:
                memcpy(data, *e100_gstrings_test, sizeof(e100_gstrings_test));
                break;
        case ETH_SS_STATS:
                memcpy(data, *e100_gstrings_stats, sizeof(e100_gstrings_stats));
                break;
        }
}

static const struct ethtool_ops e100_ethtool_ops = {
        .get_drvinfo            = e100_get_drvinfo,
        .get_regs_len           = e100_get_regs_len,
        .get_regs               = e100_get_regs,
        .get_wol                = e100_get_wol,
        .set_wol                = e100_set_wol,
        .get_msglevel           = e100_get_msglevel,
        .set_msglevel           = e100_set_msglevel,
        .nway_reset             = e100_nway_reset,
        .get_link               = e100_get_link,
        .get_eeprom_len         = e100_get_eeprom_len,
        .get_eeprom             = e100_get_eeprom,
        .set_eeprom             = e100_set_eeprom,
        .get_ringparam          = e100_get_ringparam,
        .set_ringparam          = e100_set_ringparam,
        .self_test              = e100_diag_test,
        .get_strings            = e100_get_strings,
        .set_phys_id            = e100_set_phys_id,
        .get_ethtool_stats      = e100_get_ethtool_stats,
        .get_sset_count         = e100_get_sset_count,
        .get_ts_info            = ethtool_op_get_ts_info,
        .get_link_ksettings     = e100_get_link_ksettings,
        .set_link_ksettings     = e100_set_link_ksettings,
};

static int e100_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
        struct nic *nic = netdev_priv(netdev);

        return generic_mii_ioctl(&nic->mii, if_mii(ifr), cmd, NULL);
}

static int e100_alloc(struct nic *nic)
{
        nic->mem = dma_alloc_coherent(&nic->pdev->dev, sizeof(struct mem),
                                      &nic->dma_addr, GFP_KERNEL);
        return nic->mem ? 0 : -ENOMEM;
}

static void e100_free(struct nic *nic)
{
        if (nic->mem) {
                dma_free_coherent(&nic->pdev->dev, sizeof(struct mem),
                                  nic->mem, nic->dma_addr);
                nic->mem = NULL;
        }
}

static int e100_open(struct net_device *netdev)
{
        struct nic *nic = netdev_priv(netdev);
        int err = 0;

        netif_carrier_off(netdev);
        if ((err = e100_up(nic)))
                netif_err(nic, ifup, nic->netdev, "Cannot open interface, aborting\n");
        return err;
}

static int e100_close(struct net_device *netdev)
{
        e100_down(netdev_priv(netdev));
        return 0;
}

static int e100_set_features(struct net_device *netdev,
                             netdev_features_t features)
{
        struct nic *nic = netdev_priv(netdev);
        netdev_features_t changed = features ^ netdev->features;

        if (!(changed & (NETIF_F_RXFCS | NETIF_F_RXALL)))
                return 0;

        netdev->features = features;
        e100_exec_cb(nic, NULL, e100_configure);
        return 1;
}

static const struct net_device_ops e100_netdev_ops = {
        .ndo_open               = e100_open,
        .ndo_stop               = e100_close,
        .ndo_start_xmit         = e100_xmit_frame,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_rx_mode        = e100_set_multicast_list,
        .ndo_set_mac_address    = e100_set_mac_address,
        .ndo_do_ioctl           = e100_do_ioctl,
        .ndo_tx_timeout         = e100_tx_timeout,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = e100_netpoll,
#endif
        .ndo_set_features       = e100_set_features,
};

static int e100_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        struct net_device *netdev;
        struct nic *nic;
        int err;

        if (!(netdev = alloc_etherdev(sizeof(struct nic))))
                return -ENOMEM;

        netdev->hw_features |= NETIF_F_RXFCS;
        netdev->priv_flags |= IFF_SUPP_NOFCS;
        netdev->hw_features |= NETIF_F_RXALL;

        netdev->netdev_ops = &e100_netdev_ops;
        netdev->ethtool_ops = &e100_ethtool_ops;
        netdev->watchdog_timeo = E100_WATCHDOG_PERIOD;
        strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);

        nic = netdev_priv(netdev);
        netif_napi_add(netdev, &nic->napi, e100_poll, E100_NAPI_WEIGHT);
        nic->netdev = netdev;
        nic->pdev = pdev;
        nic->msg_enable = (1 << debug) - 1;
        nic->mdio_ctrl = mdio_ctrl_hw;
        pci_set_drvdata(pdev, netdev);

        if ((err = pci_enable_device(pdev))) {
                netif_err(nic, probe, nic->netdev, "Cannot enable PCI device, aborting\n");
                goto err_out_free_dev;
        }

        if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
                netif_err(nic, probe, nic->netdev, "Cannot find proper PCI device base address, aborting\n");
                err = -ENODEV;
                goto err_out_disable_pdev;
        }

        if ((err = pci_request_regions(pdev, DRV_NAME))) {
                netif_err(nic, probe, nic->netdev, "Cannot obtain PCI resources, aborting\n");
                goto err_out_disable_pdev;
        }

        if ((err = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)))) {
                netif_err(nic, probe, nic->netdev, "No usable DMA configuration, aborting\n");
                goto err_out_free_res;
        }

        SET_NETDEV_DEV(netdev, &pdev->dev);

        if (use_io)
                netif_info(nic, probe, nic->netdev, "using i/o access mode\n");

        nic->csr = pci_iomap(pdev, (use_io ? 1 : 0), sizeof(struct csr));
        if (!nic->csr) {
                netif_err(nic, probe, nic->netdev, "Cannot map device registers, aborting\n");
                err = -ENOMEM;
                goto err_out_free_res;
        }

        if (ent->driver_data)
                nic->flags |= ich;
        else
                nic->flags &= ~ich;

        e100_get_defaults(nic);

        /* D100 MAC doesn't allow rx of vlan packets with normal MTU */
        if (nic->mac < mac_82558_D101_A4)
                netdev->features |= NETIF_F_VLAN_CHALLENGED;

        /* locks must be initialized before calling hw_reset */
        spin_lock_init(&nic->cb_lock);
        spin_lock_init(&nic->cmd_lock);
        spin_lock_init(&nic->mdio_lock);

        /* Reset the device before pci_set_master() in case device is in some
         * funky state and has an interrupt pending - hint: we don't have the
         * interrupt handler registered yet. */
        e100_hw_reset(nic);

        pci_set_master(pdev);

        timer_setup(&nic->watchdog, e100_watchdog, 0);

        INIT_WORK(&nic->tx_timeout_task, e100_tx_timeout_task);

        if ((err = e100_alloc(nic))) {
                netif_err(nic, probe, nic->netdev, "Cannot alloc driver memory, aborting\n");
                goto err_out_iounmap;
        }

        if ((err = e100_eeprom_load(nic)))
                goto err_out_free;

        e100_phy_init(nic);

        memcpy(netdev->dev_addr, nic->eeprom, ETH_ALEN);
        if (!is_valid_ether_addr(netdev->dev_addr)) {
                if (!eeprom_bad_csum_allow) {
                        netif_err(nic, probe, nic->netdev, "Invalid MAC address from EEPROM, aborting\n");
                        err = -EAGAIN;
                        goto err_out_free;
                } else {
                        netif_err(nic, probe, nic->netdev, "Invalid MAC address from EEPROM, you MUST configure one.\n");
                }
        }

        /* Wol magic packet can be enabled from eeprom */
        if ((nic->mac >= mac_82558_D101_A4) &&
           (le16_to_cpu(nic->eeprom[eeprom_id]) & eeprom_id_wol)) {
                nic->flags |= wol_magic;
                device_set_wakeup_enable(&pdev->dev, true);
        }

        /* ack any pending wake events, disable PME */
        pci_pme_active(pdev, false);

        strcpy(netdev->name, "eth%d");
        if ((err = register_netdev(netdev))) {
                netif_err(nic, probe, nic->netdev, "Cannot register net device, aborting\n");
                goto err_out_free;
        }
        nic->cbs_pool = dma_pool_create(netdev->name,
                           &nic->pdev->dev,
                           nic->params.cbs.max * sizeof(struct cb),
                           sizeof(u32),
                           0);
        if (!nic->cbs_pool) {
                netif_err(nic, probe, nic->netdev, "Cannot create DMA pool, aborting\n");
                err = -ENOMEM;
                goto err_out_pool;
        }
        netif_info(nic, probe, nic->netdev,
                   "addr 0x%llx, irq %d, MAC addr %pM\n",
                   (unsigned long long)pci_resource_start(pdev, use_io ? 1 : 0),
                   pdev->irq, netdev->dev_addr);

        return 0;

err_out_pool:
        unregister_netdev(netdev);
err_out_free:
        e100_free(nic);
err_out_iounmap:
        pci_iounmap(pdev, nic->csr);
err_out_free_res:
        pci_release_regions(pdev);
err_out_disable_pdev:
        pci_disable_device(pdev);
err_out_free_dev:
        free_netdev(netdev);
        return err;
}

static void e100_remove(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);

        if (netdev) {
                struct nic *nic = netdev_priv(netdev);
                unregister_netdev(netdev);
                e100_free(nic);
                pci_iounmap(pdev, nic->csr);
                dma_pool_destroy(nic->cbs_pool);
                free_netdev(netdev);
                pci_release_regions(pdev);
                pci_disable_device(pdev);
        }
}

#define E100_82552_SMARTSPEED   0x14   /* SmartSpeed Ctrl register */
#define E100_82552_REV_ANEG     0x0200 /* Reverse auto-negotiation */
#define E100_82552_ANEG_NOW     0x0400 /* Auto-negotiate now */
static void __e100_shutdown(struct pci_dev *pdev, bool *enable_wake)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct nic *nic = netdev_priv(netdev);

        netif_device_detach(netdev);

        if (netif_running(netdev))
                e100_down(nic);

        if ((nic->flags & wol_magic) | e100_asf(nic)) {
                /* enable reverse auto-negotiation */
                if (nic->phy == phy_82552_v) {
                        u16 smartspeed = mdio_read(netdev, nic->mii.phy_id,
                                                   E100_82552_SMARTSPEED);

                        mdio_write(netdev, nic->mii.phy_id,
                                   E100_82552_SMARTSPEED, smartspeed |
                                   E100_82552_REV_ANEG | E100_82552_ANEG_NOW);
                }
                *enable_wake = true;
        } else {
                *enable_wake = false;
        }

        pci_disable_device(pdev);
}

static int __e100_power_off(struct pci_dev *pdev, bool wake)
{
        if (wake)
                return pci_prepare_to_sleep(pdev);

        pci_wake_from_d3(pdev, false);
        pci_set_power_state(pdev, PCI_D3hot);

        return 0;
}

static int __maybe_unused e100_suspend(struct device *dev_d)
{
        bool wake;

        __e100_shutdown(to_pci_dev(dev_d), &wake);

        return 0;
}

static int __maybe_unused e100_resume(struct device *dev_d)
{
        struct net_device *netdev = dev_get_drvdata(dev_d);
        struct nic *nic = netdev_priv(netdev);
        int err;

        err = pci_enable_device(to_pci_dev(dev_d));
        if (err) {
                netdev_err(netdev, "Resume cannot enable PCI device, aborting\n");
                return err;
        }
        pci_set_master(to_pci_dev(dev_d));

        /* disable reverse auto-negotiation */
        if (nic->phy == phy_82552_v) {
                u16 smartspeed = mdio_read(netdev, nic->mii.phy_id,
                                           E100_82552_SMARTSPEED);

                mdio_write(netdev, nic->mii.phy_id,
                           E100_82552_SMARTSPEED,
                           smartspeed & ~(E100_82552_REV_ANEG));
        }

        if (netif_running(netdev))
                e100_up(nic);

        netif_device_attach(netdev);

        return 0;
}

static void e100_shutdown(struct pci_dev *pdev)
{
        bool wake;
        __e100_shutdown(pdev, &wake);
        if (system_state == SYSTEM_POWER_OFF)
                __e100_power_off(pdev, wake);
}

/* ------------------ PCI Error Recovery infrastructure  -------------- */
/**
 * e100_io_error_detected - called when PCI error is detected.
 * @pdev: Pointer to PCI device
 * @state: The current pci connection state
 */
static pci_ers_result_t e100_io_error_detected(struct pci_dev *pdev, pci_channel_state_t state)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct nic *nic = netdev_priv(netdev);

        netif_device_detach(netdev);

        if (state == pci_channel_io_perm_failure)
                return PCI_ERS_RESULT_DISCONNECT;

        if (netif_running(netdev))
                e100_down(nic);
        pci_disable_device(pdev);

        /* Request a slot reset. */
        return PCI_ERS_RESULT_NEED_RESET;
}

/**
 * e100_io_slot_reset - called after the pci bus has been reset.
 * @pdev: Pointer to PCI device
 *
 * Restart the card from scratch.
 */
static pci_ers_result_t e100_io_slot_reset(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct nic *nic = netdev_priv(netdev);

        if (pci_enable_device(pdev)) {
                pr_err("Cannot re-enable PCI device after reset\n");
                return PCI_ERS_RESULT_DISCONNECT;
        }
        pci_set_master(pdev);

        /* Only one device per card can do a reset */
        if (0 != PCI_FUNC(pdev->devfn))
                return PCI_ERS_RESULT_RECOVERED;
        e100_hw_reset(nic);
        e100_phy_init(nic);

        return PCI_ERS_RESULT_RECOVERED;
}

/**
 * e100_io_resume - resume normal operations
 * @pdev: Pointer to PCI device
 *
 * Resume normal operations after an error recovery
 * sequence has been completed.
 */
static void e100_io_resume(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct nic *nic = netdev_priv(netdev);

        /* ack any pending wake events, disable PME */
        pci_enable_wake(pdev, PCI_D0, 0);

        netif_device_attach(netdev);
        if (netif_running(netdev)) {
                e100_open(netdev);
                mod_timer(&nic->watchdog, jiffies);
        }
}

static const struct pci_error_handlers e100_err_handler = {
        .error_detected = e100_io_error_detected,
        .slot_reset = e100_io_slot_reset,
        .resume = e100_io_resume,
};

static SIMPLE_DEV_PM_OPS(e100_pm_ops, e100_suspend, e100_resume);

static struct pci_driver e100_driver = {
        .name =         DRV_NAME,
        .id_table =     e100_id_table,
        .probe =        e100_probe,
        .remove =       e100_remove,

        /* Power Management hooks */
        .driver.pm =    &e100_pm_ops,

        .shutdown =     e100_shutdown,
        .err_handler = &e100_err_handler,
};

static int __init e100_init_module(void)
{
        if (((1 << debug) - 1) & NETIF_MSG_DRV) {
                pr_info("%s\n", DRV_DESCRIPTION);
                pr_info("%s\n", DRV_COPYRIGHT);
        }
        return pci_register_driver(&e100_driver);
}

static void __exit e100_cleanup_module(void)
{
        pci_unregister_driver(&e100_driver);
}

module_init(e100_init_module);
module_exit(e100_cleanup_module);