/*************************************************************************
 * myri10ge.c: Myricom Myri-10G Ethernet driver.
 *
 * Copyright (C) 2005 - 2011 Myricom, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of Myricom, Inc. nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 *
 * If the eeprom on your board is not recent enough, you will need to get a
 * newer firmware image at:
 *   http://www.myri.com/scs/download-Myri10GE.html
 *
 * Contact Information:
 *   <help@myri.com>
 *   Myricom, Inc., 325N Santa Anita Avenue, Arcadia, CA 91006
 *************************************************************************/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/tcp.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/string.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/etherdevice.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/dca.h>
#include <linux/ip.h>
#include <linux/inet.h>
#include <linux/in.h>
#include <linux/ethtool.h>
#include <linux/firmware.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/vmalloc.h>
#include <linux/crc32.h>
#include <linux/moduleparam.h>
#include <linux/io.h>
#include <linux/log2.h>
#include <linux/slab.h>
#include <linux/prefetch.h>
#include <net/checksum.h>
#include <net/ip.h>
#include <net/tcp.h>
#include <asm/byteorder.h>
#include <asm/processor.h>

#include "myri10ge_mcp.h"
#include "myri10ge_mcp_gen_header.h"

#define MYRI10GE_VERSION_STR "1.5.3-1.534"

MODULE_DESCRIPTION("Myricom 10G driver (10GbE)");
MODULE_AUTHOR("Maintainer: help@myri.com");
MODULE_VERSION(MYRI10GE_VERSION_STR);
MODULE_LICENSE("Dual BSD/GPL");

#define MYRI10GE_MAX_ETHER_MTU 9014

#define MYRI10GE_ETH_STOPPED 0
#define MYRI10GE_ETH_STOPPING 1
#define MYRI10GE_ETH_STARTING 2
#define MYRI10GE_ETH_RUNNING 3
#define MYRI10GE_ETH_OPEN_FAILED 4

#define MYRI10GE_EEPROM_STRINGS_SIZE 256
#define MYRI10GE_MAX_SEND_DESC_TSO ((65536 / 2048) * 2)

#define MYRI10GE_NO_CONFIRM_DATA htonl(0xffffffff)
#define MYRI10GE_NO_RESPONSE_RESULT 0xffffffff

#define MYRI10GE_ALLOC_ORDER 0
#define MYRI10GE_ALLOC_SIZE ((1 << MYRI10GE_ALLOC_ORDER) * PAGE_SIZE)
#define MYRI10GE_MAX_FRAGS_PER_FRAME (MYRI10GE_MAX_ETHER_MTU/MYRI10GE_ALLOC_SIZE + 1)

#define MYRI10GE_MAX_SLICES 32

struct myri10ge_rx_buffer_state {
        struct page *page;
        int page_offset;
        DEFINE_DMA_UNMAP_ADDR(bus);
        DEFINE_DMA_UNMAP_LEN(len);
};

struct myri10ge_tx_buffer_state {
        struct sk_buff *skb;
        int last;
        DEFINE_DMA_UNMAP_ADDR(bus);
        DEFINE_DMA_UNMAP_LEN(len);
};

struct myri10ge_cmd {
        u32 data0;
        u32 data1;
        u32 data2;
};

struct myri10ge_rx_buf {
        struct mcp_kreq_ether_recv __iomem *lanai;      /* lanai ptr for recv ring */
        struct mcp_kreq_ether_recv *shadow;     /* host shadow of recv ring */
        struct myri10ge_rx_buffer_state *info;
        struct page *page;
        dma_addr_t bus;
        int page_offset;
        int cnt;
        int fill_cnt;
        int alloc_fail;
        int mask;               /* number of rx slots -1 */
        int watchdog_needed;
};

struct myri10ge_tx_buf {
        struct mcp_kreq_ether_send __iomem *lanai;      /* lanai ptr for sendq */
        __be32 __iomem *send_go;        /* "go" doorbell ptr */
        __be32 __iomem *send_stop;      /* "stop" doorbell ptr */
        struct mcp_kreq_ether_send *req_list;   /* host shadow of sendq */
        char *req_bytes;
        struct myri10ge_tx_buffer_state *info;
        int mask;               /* number of transmit slots -1  */
        int req ____cacheline_aligned;  /* transmit slots submitted     */
        int pkt_start;          /* packets started */
        int stop_queue;
        int linearized;
        int done ____cacheline_aligned; /* transmit slots completed     */
        int pkt_done;           /* packets completed */
        int wake_queue;
        int queue_active;
};

struct myri10ge_rx_done {
        struct mcp_slot *entry;
        dma_addr_t bus;
        int cnt;
        int idx;
};

struct myri10ge_slice_netstats {
        unsigned long rx_packets;
        unsigned long tx_packets;
        unsigned long rx_bytes;
        unsigned long tx_bytes;
        unsigned long rx_dropped;
        unsigned long tx_dropped;
};

struct myri10ge_slice_state {
        struct myri10ge_tx_buf tx;      /* transmit ring        */
        struct myri10ge_rx_buf rx_small;
        struct myri10ge_rx_buf rx_big;
        struct myri10ge_rx_done rx_done;
        struct net_device *dev;
        struct napi_struct napi;
        struct myri10ge_priv *mgp;
        struct myri10ge_slice_netstats stats;
        __be32 __iomem *irq_claim;
        struct mcp_irq_data *fw_stats;
        dma_addr_t fw_stats_bus;
        int watchdog_tx_done;
        int watchdog_tx_req;
        int watchdog_rx_done;
        int stuck;
#ifdef CONFIG_MYRI10GE_DCA
        int cached_dca_tag;
        int cpu;
        __be32 __iomem *dca_tag;
#endif
        char irq_desc[32];
};

struct myri10ge_priv {
        struct myri10ge_slice_state *ss;
        int tx_boundary;        /* boundary transmits cannot cross */
        int num_slices;
        int running;            /* running?             */
        int small_bytes;
        int big_bytes;
        int max_intr_slots;
        struct net_device *dev;
        u8 __iomem *sram;
        int sram_size;
        unsigned long board_span;
        unsigned long iomem_base;
        __be32 __iomem *irq_deassert;
        char *mac_addr_string;
        struct mcp_cmd_response *cmd;
        dma_addr_t cmd_bus;
        struct pci_dev *pdev;
        int msi_enabled;
        int msix_enabled;
        struct msix_entry *msix_vectors;
#ifdef CONFIG_MYRI10GE_DCA
        int dca_enabled;
        int relaxed_order;
#endif
        u32 link_state;
        unsigned int rdma_tags_available;
        int intr_coal_delay;
        __be32 __iomem *intr_coal_delay_ptr;
        int wc_cookie;
        int down_cnt;
        wait_queue_head_t down_wq;
        struct work_struct watchdog_work;
        struct timer_list watchdog_timer;
        int watchdog_resets;
        int watchdog_pause;
        int pause;
        bool fw_name_allocated;
        char *fw_name;
        char eeprom_strings[MYRI10GE_EEPROM_STRINGS_SIZE];
        char *product_code_string;
        char fw_version[128];
        int fw_ver_major;
        int fw_ver_minor;
        int fw_ver_tiny;
        int adopted_rx_filter_bug;
        u8 mac_addr[ETH_ALEN];          /* eeprom mac address */
        unsigned long serial_number;
        int vendor_specific_offset;
        int fw_multicast_support;
        u32 features;
        u32 max_tso6;
        u32 read_dma;
        u32 write_dma;
        u32 read_write_dma;
        u32 link_changes;
        u32 msg_enable;
        unsigned int board_number;
        int rebooted;
};

static char *myri10ge_fw_unaligned = "myri10ge_ethp_z8e.dat";
static char *myri10ge_fw_aligned = "myri10ge_eth_z8e.dat";
static char *myri10ge_fw_rss_unaligned = "myri10ge_rss_ethp_z8e.dat";
static char *myri10ge_fw_rss_aligned = "myri10ge_rss_eth_z8e.dat";
MODULE_FIRMWARE("myri10ge_ethp_z8e.dat");
MODULE_FIRMWARE("myri10ge_eth_z8e.dat");
MODULE_FIRMWARE("myri10ge_rss_ethp_z8e.dat");
MODULE_FIRMWARE("myri10ge_rss_eth_z8e.dat");

/* Careful: must be accessed under kernel_param_lock() */
static char *myri10ge_fw_name = NULL;
module_param(myri10ge_fw_name, charp, 0644);
MODULE_PARM_DESC(myri10ge_fw_name, "Firmware image name");

#define MYRI10GE_MAX_BOARDS 8
static char *myri10ge_fw_names[MYRI10GE_MAX_BOARDS] =
    {[0 ... (MYRI10GE_MAX_BOARDS - 1)] = NULL };
module_param_array_named(myri10ge_fw_names, myri10ge_fw_names, charp, NULL,
                         0444);
MODULE_PARM_DESC(myri10ge_fw_names, "Firmware image names per board");

static int myri10ge_ecrc_enable = 1;
module_param(myri10ge_ecrc_enable, int, 0444);
MODULE_PARM_DESC(myri10ge_ecrc_enable, "Enable Extended CRC on PCI-E");

static int myri10ge_small_bytes = -1;   /* -1 == auto */
module_param(myri10ge_small_bytes, int, 0644);
MODULE_PARM_DESC(myri10ge_small_bytes, "Threshold of small packets");

static int myri10ge_msi = 1;    /* enable msi by default */
module_param(myri10ge_msi, int, 0644);
MODULE_PARM_DESC(myri10ge_msi, "Enable Message Signalled Interrupts");

static int myri10ge_intr_coal_delay = 75;
module_param(myri10ge_intr_coal_delay, int, 0444);
MODULE_PARM_DESC(myri10ge_intr_coal_delay, "Interrupt coalescing delay");

static int myri10ge_flow_control = 1;
module_param(myri10ge_flow_control, int, 0444);
MODULE_PARM_DESC(myri10ge_flow_control, "Pause parameter");

static int myri10ge_deassert_wait = 1;
module_param(myri10ge_deassert_wait, int, 0644);
MODULE_PARM_DESC(myri10ge_deassert_wait,
                 "Wait when deasserting legacy interrupts");

static int myri10ge_force_firmware = 0;
module_param(myri10ge_force_firmware, int, 0444);
MODULE_PARM_DESC(myri10ge_force_firmware,
                 "Force firmware to assume aligned completions");

static int myri10ge_initial_mtu = MYRI10GE_MAX_ETHER_MTU - ETH_HLEN;
module_param(myri10ge_initial_mtu, int, 0444);
MODULE_PARM_DESC(myri10ge_initial_mtu, "Initial MTU");

static int myri10ge_napi_weight = 64;
module_param(myri10ge_napi_weight, int, 0444);
MODULE_PARM_DESC(myri10ge_napi_weight, "Set NAPI weight");

static int myri10ge_watchdog_timeout = 1;
module_param(myri10ge_watchdog_timeout, int, 0444);
MODULE_PARM_DESC(myri10ge_watchdog_timeout, "Set watchdog timeout");

static int myri10ge_max_irq_loops = 1048576;
module_param(myri10ge_max_irq_loops, int, 0444);
MODULE_PARM_DESC(myri10ge_max_irq_loops,
                 "Set stuck legacy IRQ detection threshold");

#define MYRI10GE_MSG_DEFAULT NETIF_MSG_LINK

static int myri10ge_debug = -1; /* defaults above */
module_param(myri10ge_debug, int, 0);
MODULE_PARM_DESC(myri10ge_debug, "Debug level (0=none,...,16=all)");

static int myri10ge_fill_thresh = 256;
module_param(myri10ge_fill_thresh, int, 0644);
MODULE_PARM_DESC(myri10ge_fill_thresh, "Number of empty rx slots allowed");

static int myri10ge_reset_recover = 1;

static int myri10ge_max_slices = 1;
module_param(myri10ge_max_slices, int, 0444);
MODULE_PARM_DESC(myri10ge_max_slices, "Max tx/rx queues");

static int myri10ge_rss_hash = MXGEFW_RSS_HASH_TYPE_SRC_DST_PORT;
module_param(myri10ge_rss_hash, int, 0444);
MODULE_PARM_DESC(myri10ge_rss_hash, "Type of RSS hashing to do");

static int myri10ge_dca = 1;
module_param(myri10ge_dca, int, 0444);
MODULE_PARM_DESC(myri10ge_dca, "Enable DCA if possible");

#define MYRI10GE_FW_OFFSET 1024*1024
#define MYRI10GE_HIGHPART_TO_U32(X) \
(sizeof (X) == 8) ? ((u32)((u64)(X) >> 32)) : (0)
#define MYRI10GE_LOWPART_TO_U32(X) ((u32)(X))

#define myri10ge_pio_copy(to,from,size) __iowrite64_copy(to,from,size/8)

static void myri10ge_set_multicast_list(struct net_device *dev);
static netdev_tx_t myri10ge_sw_tso(struct sk_buff *skb,
                                         struct net_device *dev);

static inline void put_be32(__be32 val, __be32 __iomem * p)
{
        __raw_writel((__force __u32) val, (__force void __iomem *)p);
}

static void myri10ge_get_stats(struct net_device *dev,
                               struct rtnl_link_stats64 *stats);

static void set_fw_name(struct myri10ge_priv *mgp, char *name, bool allocated)
{
        if (mgp->fw_name_allocated)
                kfree(mgp->fw_name);
        mgp->fw_name = name;
        mgp->fw_name_allocated = allocated;
}

static int
myri10ge_send_cmd(struct myri10ge_priv *mgp, u32 cmd,
                  struct myri10ge_cmd *data, int atomic)
{
        struct mcp_cmd *buf;
        char buf_bytes[sizeof(*buf) + 8];
        struct mcp_cmd_response *response = mgp->cmd;
        char __iomem *cmd_addr = mgp->sram + MXGEFW_ETH_CMD;
        u32 dma_low, dma_high, result, value;
        int sleep_total = 0;

        /* ensure buf is aligned to 8 bytes */
        buf = (struct mcp_cmd *)ALIGN((unsigned long)buf_bytes, 8);

        buf->data0 = htonl(data->data0);
        buf->data1 = htonl(data->data1);
        buf->data2 = htonl(data->data2);
        buf->cmd = htonl(cmd);
        dma_low = MYRI10GE_LOWPART_TO_U32(mgp->cmd_bus);
        dma_high = MYRI10GE_HIGHPART_TO_U32(mgp->cmd_bus);

        buf->response_addr.low = htonl(dma_low);
        buf->response_addr.high = htonl(dma_high);
        response->result = htonl(MYRI10GE_NO_RESPONSE_RESULT);
        mb();
        myri10ge_pio_copy(cmd_addr, buf, sizeof(*buf));

        /* wait up to 15ms. Longest command is the DMA benchmark,
         * which is capped at 5ms, but runs from a timeout handler
         * that runs every 7.8ms. So a 15ms timeout leaves us with
         * a 2.2ms margin
         */
        if (atomic) {
                /* if atomic is set, do not sleep,
                 * and try to get the completion quickly
                 * (1ms will be enough for those commands) */
                for (sleep_total = 0;
                     sleep_total < 1000 &&
                     response->result == htonl(MYRI10GE_NO_RESPONSE_RESULT);
                     sleep_total += 10) {
                        udelay(10);
                        mb();
                }
        } else {
                /* use msleep for most command */
                for (sleep_total = 0;
                     sleep_total < 15 &&
                     response->result == htonl(MYRI10GE_NO_RESPONSE_RESULT);
                     sleep_total++)
                        msleep(1);
        }

        result = ntohl(response->result);
        value = ntohl(response->data);
        if (result != MYRI10GE_NO_RESPONSE_RESULT) {
                if (result == 0) {
                        data->data0 = value;
                        return 0;
                } else if (result == MXGEFW_CMD_UNKNOWN) {
                        return -ENOSYS;
                } else if (result == MXGEFW_CMD_ERROR_UNALIGNED) {
                        return -E2BIG;
                } else if (result == MXGEFW_CMD_ERROR_RANGE &&
                           cmd == MXGEFW_CMD_ENABLE_RSS_QUEUES &&
                           (data->
                            data1 & MXGEFW_SLICE_ENABLE_MULTIPLE_TX_QUEUES) !=
                           0) {
                        return -ERANGE;
                } else {
                        dev_err(&mgp->pdev->dev,
                                "command %d failed, result = %d\n",
                                cmd, result);
                        return -ENXIO;
                }
        }

        dev_err(&mgp->pdev->dev, "command %d timed out, result = %d\n",
                cmd, result);
        return -EAGAIN;
}

/*
 * The eeprom strings on the lanaiX have the format
 * SN=x\0
 * MAC=x:x:x:x:x:x\0
 * PT:ddd mmm xx xx:xx:xx xx\0
 * PV:ddd mmm xx xx:xx:xx xx\0
 */
static int myri10ge_read_mac_addr(struct myri10ge_priv *mgp)
{
        char *ptr, *limit;
        int i;

        ptr = mgp->eeprom_strings;
        limit = mgp->eeprom_strings + MYRI10GE_EEPROM_STRINGS_SIZE;

        while (*ptr != '\0' && ptr < limit) {
                if (memcmp(ptr, "MAC=", 4) == 0) {
                        ptr += 4;
                        mgp->mac_addr_string = ptr;
                        for (i = 0; i < 6; i++) {
                                if ((ptr + 2) > limit)
                                        goto abort;
                                mgp->mac_addr[i] =
                                    simple_strtoul(ptr, &ptr, 16);
                                ptr += 1;
                        }
                }
                if (memcmp(ptr, "PC=", 3) == 0) {
                        ptr += 3;
                        mgp->product_code_string = ptr;
                }
                if (memcmp((const void *)ptr, "SN=", 3) == 0) {
                        ptr += 3;
                        mgp->serial_number = simple_strtoul(ptr, &ptr, 10);
                }
                while (ptr < limit && *ptr++) ;
        }

        return 0;

abort:
        dev_err(&mgp->pdev->dev, "failed to parse eeprom_strings\n");
        return -ENXIO;
}

/*
 * Enable or disable periodic RDMAs from the host to make certain
 * chipsets resend dropped PCIe messages
 */

static void myri10ge_dummy_rdma(struct myri10ge_priv *mgp, int enable)
{
        char __iomem *submit;
        __be32 buf[16] __attribute__ ((__aligned__(8)));
        u32 dma_low, dma_high;
        int i;

        /* clear confirmation addr */
        mgp->cmd->data = 0;
        mb();

        /* send a rdma command to the PCIe engine, and wait for the
         * response in the confirmation address.  The firmware should
         * write a -1 there to indicate it is alive and well
         */
        dma_low = MYRI10GE_LOWPART_TO_U32(mgp->cmd_bus);
        dma_high = MYRI10GE_HIGHPART_TO_U32(mgp->cmd_bus);

        buf[0] = htonl(dma_high);       /* confirm addr MSW */
        buf[1] = htonl(dma_low);        /* confirm addr LSW */
        buf[2] = MYRI10GE_NO_CONFIRM_DATA;      /* confirm data */
        buf[3] = htonl(dma_high);       /* dummy addr MSW */
        buf[4] = htonl(dma_low);        /* dummy addr LSW */
        buf[5] = htonl(enable); /* enable? */

        submit = mgp->sram + MXGEFW_BOOT_DUMMY_RDMA;

        myri10ge_pio_copy(submit, &buf, sizeof(buf));
        for (i = 0; mgp->cmd->data != MYRI10GE_NO_CONFIRM_DATA && i < 20; i++)
                msleep(1);
        if (mgp->cmd->data != MYRI10GE_NO_CONFIRM_DATA)
                dev_err(&mgp->pdev->dev, "dummy rdma %s failed\n",
                        (enable ? "enable" : "disable"));
}

static int
myri10ge_validate_firmware(struct myri10ge_priv *mgp,
                           struct mcp_gen_header *hdr)
{
        struct device *dev = &mgp->pdev->dev;

        /* check firmware type */
        if (ntohl(hdr->mcp_type) != MCP_TYPE_ETH) {
                dev_err(dev, "Bad firmware type: 0x%x\n", ntohl(hdr->mcp_type));
                return -EINVAL;
        }

        /* save firmware version for ethtool */
        strncpy(mgp->fw_version, hdr->version, sizeof(mgp->fw_version));
        mgp->fw_version[sizeof(mgp->fw_version) - 1] = '\0';

        sscanf(mgp->fw_version, "%d.%d.%d", &mgp->fw_ver_major,
               &mgp->fw_ver_minor, &mgp->fw_ver_tiny);

        if (!(mgp->fw_ver_major == MXGEFW_VERSION_MAJOR &&
              mgp->fw_ver_minor == MXGEFW_VERSION_MINOR)) {
                dev_err(dev, "Found firmware version %s\n", mgp->fw_version);
                dev_err(dev, "Driver needs %d.%d\n", MXGEFW_VERSION_MAJOR,
                        MXGEFW_VERSION_MINOR);
                return -EINVAL;
        }
        return 0;
}

static int myri10ge_load_hotplug_firmware(struct myri10ge_priv *mgp, u32 * size)
{
        unsigned crc, reread_crc;
        const struct firmware *fw;
        struct device *dev = &mgp->pdev->dev;
        unsigned char *fw_readback;
        struct mcp_gen_header *hdr;
        size_t hdr_offset;
        int status;
        unsigned i;

        if ((status = request_firmware(&fw, mgp->fw_name, dev)) < 0) {
                dev_err(dev, "Unable to load %s firmware image via hotplug\n",
                        mgp->fw_name);
                status = -EINVAL;
                goto abort_with_nothing;
        }

        /* check size */

        if (fw->size >= mgp->sram_size - MYRI10GE_FW_OFFSET ||
            fw->size < MCP_HEADER_PTR_OFFSET + 4) {
                dev_err(dev, "Firmware size invalid:%d\n", (int)fw->size);
                status = -EINVAL;
                goto abort_with_fw;
        }

        /* check id */
        hdr_offset = ntohl(*(__be32 *) (fw->data + MCP_HEADER_PTR_OFFSET));
        if ((hdr_offset & 3) || hdr_offset + sizeof(*hdr) > fw->size) {
                dev_err(dev, "Bad firmware file\n");
                status = -EINVAL;
                goto abort_with_fw;
        }
        hdr = (void *)(fw->data + hdr_offset);

        status = myri10ge_validate_firmware(mgp, hdr);
        if (status != 0)
                goto abort_with_fw;

        crc = crc32(~0, fw->data, fw->size);
        for (i = 0; i < fw->size; i += 256) {
                myri10ge_pio_copy(mgp->sram + MYRI10GE_FW_OFFSET + i,
                                  fw->data + i,
                                  min(256U, (unsigned)(fw->size - i)));
                mb();
                readb(mgp->sram);
        }
        fw_readback = vmalloc(fw->size);
        if (!fw_readback) {
                status = -ENOMEM;
                goto abort_with_fw;
        }
        /* corruption checking is good for parity recovery and buggy chipset */
        memcpy_fromio(fw_readback, mgp->sram + MYRI10GE_FW_OFFSET, fw->size);
        reread_crc = crc32(~0, fw_readback, fw->size);
        vfree(fw_readback);
        if (crc != reread_crc) {
                dev_err(dev, "CRC failed(fw-len=%u), got 0x%x (expect 0x%x)\n",
                        (unsigned)fw->size, reread_crc, crc);
                status = -EIO;
                goto abort_with_fw;
        }
        *size = (u32) fw->size;

abort_with_fw:
        release_firmware(fw);

abort_with_nothing:
        return status;
}

static int myri10ge_adopt_running_firmware(struct myri10ge_priv *mgp)
{
        struct mcp_gen_header *hdr;
        struct device *dev = &mgp->pdev->dev;
        const size_t bytes = sizeof(struct mcp_gen_header);
        size_t hdr_offset;
        int status;

        /* find running firmware header */
        hdr_offset = swab32(readl(mgp->sram + MCP_HEADER_PTR_OFFSET));

        if ((hdr_offset & 3) || hdr_offset + sizeof(*hdr) > mgp->sram_size) {
                dev_err(dev, "Running firmware has bad header offset (%d)\n",
                        (int)hdr_offset);
                return -EIO;
        }

        /* copy header of running firmware from SRAM to host memory to
         * validate firmware */
        hdr = kmalloc(bytes, GFP_KERNEL);
        if (hdr == NULL)
                return -ENOMEM;

        memcpy_fromio(hdr, mgp->sram + hdr_offset, bytes);
        status = myri10ge_validate_firmware(mgp, hdr);
        kfree(hdr);

        /* check to see if adopted firmware has bug where adopting
         * it will cause broadcasts to be filtered unless the NIC
         * is kept in ALLMULTI mode */
        if (mgp->fw_ver_major == 1 && mgp->fw_ver_minor == 4 &&
            mgp->fw_ver_tiny >= 4 && mgp->fw_ver_tiny <= 11) {
                mgp->adopted_rx_filter_bug = 1;
                dev_warn(dev, "Adopting fw %d.%d.%d: "
                         "working around rx filter bug\n",
                         mgp->fw_ver_major, mgp->fw_ver_minor,
                         mgp->fw_ver_tiny);
        }
        return status;
}

static int myri10ge_get_firmware_capabilities(struct myri10ge_priv *mgp)
{
        struct myri10ge_cmd cmd;
        int status;

        /* probe for IPv6 TSO support */
        mgp->features = NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_TSO;
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_MAX_TSO6_HDR_SIZE,
                                   &cmd, 0);
        if (status == 0) {
                mgp->max_tso6 = cmd.data0;
                mgp->features |= NETIF_F_TSO6;
        }

        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_RX_RING_SIZE, &cmd, 0);
        if (status != 0) {
                dev_err(&mgp->pdev->dev,
                        "failed MXGEFW_CMD_GET_RX_RING_SIZE\n");
                return -ENXIO;
        }

        mgp->max_intr_slots = 2 * (cmd.data0 / sizeof(struct mcp_dma_addr));

        return 0;
}

static int myri10ge_load_firmware(struct myri10ge_priv *mgp, int adopt)
{
        char __iomem *submit;
        __be32 buf[16] __attribute__ ((__aligned__(8)));
        u32 dma_low, dma_high, size;
        int status, i;

        size = 0;
        status = myri10ge_load_hotplug_firmware(mgp, &size);
        if (status) {
                if (!adopt)
                        return status;
                dev_warn(&mgp->pdev->dev, "hotplug firmware loading failed\n");

                /* Do not attempt to adopt firmware if there
                 * was a bad crc */
                if (status == -EIO)
                        return status;

                status = myri10ge_adopt_running_firmware(mgp);
                if (status != 0) {
                        dev_err(&mgp->pdev->dev,
                                "failed to adopt running firmware\n");
                        return status;
                }
                dev_info(&mgp->pdev->dev,
                         "Successfully adopted running firmware\n");
                if (mgp->tx_boundary == 4096) {
                        dev_warn(&mgp->pdev->dev,
                                 "Using firmware currently running on NIC"
                                 ".  For optimal\n");
                        dev_warn(&mgp->pdev->dev,
                                 "performance consider loading optimized "
                                 "firmware\n");
                        dev_warn(&mgp->pdev->dev, "via hotplug\n");
                }

                set_fw_name(mgp, "adopted", false);
                mgp->tx_boundary = 2048;
                myri10ge_dummy_rdma(mgp, 1);
                status = myri10ge_get_firmware_capabilities(mgp);
                return status;
        }

        /* clear confirmation addr */
        mgp->cmd->data = 0;
        mb();

        /* send a reload command to the bootstrap MCP, and wait for the
         *  response in the confirmation address.  The firmware should
         * write a -1 there to indicate it is alive and well
         */
        dma_low = MYRI10GE_LOWPART_TO_U32(mgp->cmd_bus);
        dma_high = MYRI10GE_HIGHPART_TO_U32(mgp->cmd_bus);

        buf[0] = htonl(dma_high);       /* confirm addr MSW */
        buf[1] = htonl(dma_low);        /* confirm addr LSW */
        buf[2] = MYRI10GE_NO_CONFIRM_DATA;      /* confirm data */

        /* FIX: All newest firmware should un-protect the bottom of
         * the sram before handoff. However, the very first interfaces
         * do not. Therefore the handoff copy must skip the first 8 bytes
         */
        buf[3] = htonl(MYRI10GE_FW_OFFSET + 8); /* where the code starts */
        buf[4] = htonl(size - 8);       /* length of code */
        buf[5] = htonl(8);      /* where to copy to */
        buf[6] = htonl(0);      /* where to jump to */

        submit = mgp->sram + MXGEFW_BOOT_HANDOFF;

        myri10ge_pio_copy(submit, &buf, sizeof(buf));
        mb();
        msleep(1);
        mb();
        i = 0;
        while (mgp->cmd->data != MYRI10GE_NO_CONFIRM_DATA && i < 9) {
                msleep(1 << i);
                i++;
        }
        if (mgp->cmd->data != MYRI10GE_NO_CONFIRM_DATA) {
                dev_err(&mgp->pdev->dev, "handoff failed\n");
                return -ENXIO;
        }
        myri10ge_dummy_rdma(mgp, 1);
        status = myri10ge_get_firmware_capabilities(mgp);

        return status;
}

static int myri10ge_update_mac_address(struct myri10ge_priv *mgp, u8 * addr)
{
        struct myri10ge_cmd cmd;
        int status;

        cmd.data0 = ((addr[0] << 24) | (addr[1] << 16)
                     | (addr[2] << 8) | addr[3]);

        cmd.data1 = ((addr[4] << 8) | (addr[5]));

        status = myri10ge_send_cmd(mgp, MXGEFW_SET_MAC_ADDRESS, &cmd, 0);
        return status;
}

static int myri10ge_change_pause(struct myri10ge_priv *mgp, int pause)
{
        struct myri10ge_cmd cmd;
        int status, ctl;

        ctl = pause ? MXGEFW_ENABLE_FLOW_CONTROL : MXGEFW_DISABLE_FLOW_CONTROL;
        status = myri10ge_send_cmd(mgp, ctl, &cmd, 0);

        if (status) {
                netdev_err(mgp->dev, "Failed to set flow control mode\n");
                return status;
        }
        mgp->pause = pause;
        return 0;
}

static void
myri10ge_change_promisc(struct myri10ge_priv *mgp, int promisc, int atomic)
{
        struct myri10ge_cmd cmd;
        int status, ctl;

        ctl = promisc ? MXGEFW_ENABLE_PROMISC : MXGEFW_DISABLE_PROMISC;
        status = myri10ge_send_cmd(mgp, ctl, &cmd, atomic);
        if (status)
                netdev_err(mgp->dev, "Failed to set promisc mode\n");
}

static int myri10ge_dma_test(struct myri10ge_priv *mgp, int test_type)
{
        struct myri10ge_cmd cmd;
        int status;
        u32 len;
        struct page *dmatest_page;
        dma_addr_t dmatest_bus;
        char *test = " ";

        dmatest_page = alloc_page(GFP_KERNEL);
        if (!dmatest_page)
                return -ENOMEM;
        dmatest_bus = pci_map_page(mgp->pdev, dmatest_page, 0, PAGE_SIZE,
                                   DMA_BIDIRECTIONAL);
        if (unlikely(pci_dma_mapping_error(mgp->pdev, dmatest_bus))) {
                __free_page(dmatest_page);
                return -ENOMEM;
        }

        /* Run a small DMA test.
         * The magic multipliers to the length tell the firmware
         * to do DMA read, write, or read+write tests.  The
         * results are returned in cmd.data0.  The upper 16
         * bits or the return is the number of transfers completed.
         * The lower 16 bits is the time in 0.5us ticks that the
         * transfers took to complete.
         */

        len = mgp->tx_boundary;

        cmd.data0 = MYRI10GE_LOWPART_TO_U32(dmatest_bus);
        cmd.data1 = MYRI10GE_HIGHPART_TO_U32(dmatest_bus);
        cmd.data2 = len * 0x10000;
        status = myri10ge_send_cmd(mgp, test_type, &cmd, 0);
        if (status != 0) {
                test = "read";
                goto abort;
        }
        mgp->read_dma = ((cmd.data0 >> 16) * len * 2) / (cmd.data0 & 0xffff);
        cmd.data0 = MYRI10GE_LOWPART_TO_U32(dmatest_bus);
        cmd.data1 = MYRI10GE_HIGHPART_TO_U32(dmatest_bus);
        cmd.data2 = len * 0x1;
        status = myri10ge_send_cmd(mgp, test_type, &cmd, 0);
        if (status != 0) {
                test = "write";
                goto abort;
        }
        mgp->write_dma = ((cmd.data0 >> 16) * len * 2) / (cmd.data0 & 0xffff);

        cmd.data0 = MYRI10GE_LOWPART_TO_U32(dmatest_bus);
        cmd.data1 = MYRI10GE_HIGHPART_TO_U32(dmatest_bus);
        cmd.data2 = len * 0x10001;
        status = myri10ge_send_cmd(mgp, test_type, &cmd, 0);
        if (status != 0) {
                test = "read/write";
                goto abort;
        }
        mgp->read_write_dma = ((cmd.data0 >> 16) * len * 2 * 2) /
            (cmd.data0 & 0xffff);

abort:
        pci_unmap_page(mgp->pdev, dmatest_bus, PAGE_SIZE, DMA_BIDIRECTIONAL);
        put_page(dmatest_page);

        if (status != 0 && test_type != MXGEFW_CMD_UNALIGNED_TEST)
                dev_warn(&mgp->pdev->dev, "DMA %s benchmark failed: %d\n",
                         test, status);

        return status;
}

static int myri10ge_reset(struct myri10ge_priv *mgp)
{
        struct myri10ge_cmd cmd;
        struct myri10ge_slice_state *ss;
        int i, status;
        size_t bytes;
#ifdef CONFIG_MYRI10GE_DCA
        unsigned long dca_tag_off;
#endif

        /* try to send a reset command to the card to see if it
         * is alive */
        memset(&cmd, 0, sizeof(cmd));
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_RESET, &cmd, 0);
        if (status != 0) {
                dev_err(&mgp->pdev->dev, "failed reset\n");
                return -ENXIO;
        }

        (void)myri10ge_dma_test(mgp, MXGEFW_DMA_TEST);
        /*
         * Use non-ndis mcp_slot (eg, 4 bytes total,
         * no toeplitz hash value returned.  Older firmware will
         * not understand this command, but will use the correct
         * sized mcp_slot, so we ignore error returns
         */
        cmd.data0 = MXGEFW_RSS_MCP_SLOT_TYPE_MIN;
        (void)myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_RSS_MCP_SLOT_TYPE, &cmd, 0);

        /* Now exchange information about interrupts  */

        bytes = mgp->max_intr_slots * sizeof(*mgp->ss[0].rx_done.entry);
        cmd.data0 = (u32) bytes;
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_INTRQ_SIZE, &cmd, 0);

        /*
         * Even though we already know how many slices are supported
         * via myri10ge_probe_slices() MXGEFW_CMD_GET_MAX_RSS_QUEUES
         * has magic side effects, and must be called after a reset.
         * It must be called prior to calling any RSS related cmds,
         * including assigning an interrupt queue for anything but
         * slice 0.  It must also be called *after*
         * MXGEFW_CMD_SET_INTRQ_SIZE, since the intrq size is used by
         * the firmware to compute offsets.
         */

        if (mgp->num_slices > 1) {

                /* ask the maximum number of slices it supports */
                status = myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_MAX_RSS_QUEUES,
                                           &cmd, 0);
                if (status != 0) {
                        dev_err(&mgp->pdev->dev,
                                "failed to get number of slices\n");
                }

                /*
                 * MXGEFW_CMD_ENABLE_RSS_QUEUES must be called prior
                 * to setting up the interrupt queue DMA
                 */

                cmd.data0 = mgp->num_slices;
                cmd.data1 = MXGEFW_SLICE_INTR_MODE_ONE_PER_SLICE;
                if (mgp->dev->real_num_tx_queues > 1)
                        cmd.data1 |= MXGEFW_SLICE_ENABLE_MULTIPLE_TX_QUEUES;
                status = myri10ge_send_cmd(mgp, MXGEFW_CMD_ENABLE_RSS_QUEUES,
                                           &cmd, 0);

                /* Firmware older than 1.4.32 only supports multiple
                 * RX queues, so if we get an error, first retry using a
                 * single TX queue before giving up */
                if (status != 0 && mgp->dev->real_num_tx_queues > 1) {
                        netif_set_real_num_tx_queues(mgp->dev, 1);
                        cmd.data0 = mgp->num_slices;
                        cmd.data1 = MXGEFW_SLICE_INTR_MODE_ONE_PER_SLICE;
                        status = myri10ge_send_cmd(mgp,
                                                   MXGEFW_CMD_ENABLE_RSS_QUEUES,
                                                   &cmd, 0);
                }

                if (status != 0) {
                        dev_err(&mgp->pdev->dev,
                                "failed to set number of slices\n");

                        return status;
                }
        }
        for (i = 0; i < mgp->num_slices; i++) {
                ss = &mgp->ss[i];

                cmd.data0 = MYRI10GE_LOWPART_TO_U32(ss->rx_done.bus);
                cmd.data1 = MYRI10GE_HIGHPART_TO_U32(ss->rx_done.bus);
                cmd.data2 = i;
                status |= myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_INTRQ_DMA,
                                            &cmd, 0);
        }

        status |=
            myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_IRQ_ACK_OFFSET, &cmd, 0);
        for (i = 0; i < mgp->num_slices; i++) {
                ss = &mgp->ss[i];
                ss->irq_claim =
                    (__iomem __be32 *) (mgp->sram + cmd.data0 + 8 * i);
        }
        status |= myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_IRQ_DEASSERT_OFFSET,
                                    &cmd, 0);
        mgp->irq_deassert = (__iomem __be32 *) (mgp->sram + cmd.data0);

        status |= myri10ge_send_cmd
            (mgp, MXGEFW_CMD_GET_INTR_COAL_DELAY_OFFSET, &cmd, 0);
        mgp->intr_coal_delay_ptr = (__iomem __be32 *) (mgp->sram + cmd.data0);
        if (status != 0) {
                dev_err(&mgp->pdev->dev, "failed set interrupt parameters\n");
                return status;
        }
        put_be32(htonl(mgp->intr_coal_delay), mgp->intr_coal_delay_ptr);

#ifdef CONFIG_MYRI10GE_DCA
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_DCA_OFFSET, &cmd, 0);
        dca_tag_off = cmd.data0;
        for (i = 0; i < mgp->num_slices; i++) {
                ss = &mgp->ss[i];
                if (status == 0) {
                        ss->dca_tag = (__iomem __be32 *)
                            (mgp->sram + dca_tag_off + 4 * i);
                } else {
                        ss->dca_tag = NULL;
                }
        }
#endif                          /* CONFIG_MYRI10GE_DCA */

        /* reset mcp/driver shared state back to 0 */

        mgp->link_changes = 0;
        for (i = 0; i < mgp->num_slices; i++) {
                ss = &mgp->ss[i];

                memset(ss->rx_done.entry, 0, bytes);
                ss->tx.req = 0;
                ss->tx.done = 0;
                ss->tx.pkt_start = 0;
                ss->tx.pkt_done = 0;
                ss->rx_big.cnt = 0;
                ss->rx_small.cnt = 0;
                ss->rx_done.idx = 0;
                ss->rx_done.cnt = 0;
                ss->tx.wake_queue = 0;
                ss->tx.stop_queue = 0;
        }

        status = myri10ge_update_mac_address(mgp, mgp->dev->dev_addr);
        myri10ge_change_pause(mgp, mgp->pause);
        myri10ge_set_multicast_list(mgp->dev);
        return status;
}

#ifdef CONFIG_MYRI10GE_DCA
static int myri10ge_toggle_relaxed(struct pci_dev *pdev, int on)
{
        int ret;
        u16 ctl;

        pcie_capability_read_word(pdev, PCI_EXP_DEVCTL, &ctl);

        ret = (ctl & PCI_EXP_DEVCTL_RELAX_EN) >> 4;
        if (ret != on) {
                ctl &= ~PCI_EXP_DEVCTL_RELAX_EN;
                ctl |= (on << 4);
                pcie_capability_write_word(pdev, PCI_EXP_DEVCTL, ctl);
        }
        return ret;
}

static void
myri10ge_write_dca(struct myri10ge_slice_state *ss, int cpu, int tag)
{
        ss->cached_dca_tag = tag;
        put_be32(htonl(tag), ss->dca_tag);
}

static inline void myri10ge_update_dca(struct myri10ge_slice_state *ss)
{
        int cpu = get_cpu();
        int tag;

        if (cpu != ss->cpu) {
                tag = dca3_get_tag(&ss->mgp->pdev->dev, cpu);
                if (ss->cached_dca_tag != tag)
                        myri10ge_write_dca(ss, cpu, tag);
                ss->cpu = cpu;
        }
        put_cpu();
}

static void myri10ge_setup_dca(struct myri10ge_priv *mgp)
{
        int err, i;
        struct pci_dev *pdev = mgp->pdev;

        if (mgp->ss[0].dca_tag == NULL || mgp->dca_enabled)
                return;
        if (!myri10ge_dca) {
                dev_err(&pdev->dev, "dca disabled by administrator\n");
                return;
        }
        err = dca_add_requester(&pdev->dev);
        if (err) {
                if (err != -ENODEV)
                        dev_err(&pdev->dev,
                                "dca_add_requester() failed, err=%d\n", err);
                return;
        }
        mgp->relaxed_order = myri10ge_toggle_relaxed(pdev, 0);
        mgp->dca_enabled = 1;
        for (i = 0; i < mgp->num_slices; i++) {
                mgp->ss[i].cpu = -1;
                mgp->ss[i].cached_dca_tag = -1;
                myri10ge_update_dca(&mgp->ss[i]);
        }
}

static void myri10ge_teardown_dca(struct myri10ge_priv *mgp)
{
        struct pci_dev *pdev = mgp->pdev;

        if (!mgp->dca_enabled)
                return;
        mgp->dca_enabled = 0;
        if (mgp->relaxed_order)
                myri10ge_toggle_relaxed(pdev, 1);
        dca_remove_requester(&pdev->dev);
}

static int myri10ge_notify_dca_device(struct device *dev, void *data)
{
        struct myri10ge_priv *mgp;
        unsigned long event;

        mgp = dev_get_drvdata(dev);
        event = *(unsigned long *)data;

        if (event == DCA_PROVIDER_ADD)
                myri10ge_setup_dca(mgp);
        else if (event == DCA_PROVIDER_REMOVE)
                myri10ge_teardown_dca(mgp);
        return 0;
}
#endif                          /* CONFIG_MYRI10GE_DCA */

static inline void
myri10ge_submit_8rx(struct mcp_kreq_ether_recv __iomem * dst,
                    struct mcp_kreq_ether_recv *src)
{
        __be32 low;

        low = src->addr_low;
        src->addr_low = htonl(DMA_BIT_MASK(32));
        myri10ge_pio_copy(dst, src, 4 * sizeof(*src));
        mb();
        myri10ge_pio_copy(dst + 4, src + 4, 4 * sizeof(*src));
        mb();
        src->addr_low = low;
        put_be32(low, &dst->addr_low);
        mb();
}

static inline void myri10ge_vlan_ip_csum(struct sk_buff *skb, __wsum hw_csum)
{
        struct vlan_hdr *vh = (struct vlan_hdr *)(skb->data);

        if ((skb->protocol == htons(ETH_P_8021Q)) &&
            (vh->h_vlan_encapsulated_proto == htons(ETH_P_IP) ||
             vh->h_vlan_encapsulated_proto == htons(ETH_P_IPV6))) {
                skb->csum = hw_csum;
                skb->ip_summed = CHECKSUM_COMPLETE;
        }
}

static void
myri10ge_alloc_rx_pages(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
                        int bytes, int watchdog)
{
        struct page *page;
        dma_addr_t bus;
        int idx;
#if MYRI10GE_ALLOC_SIZE > 4096
        int end_offset;
#endif

        if (unlikely(rx->watchdog_needed && !watchdog))
                return;

        /* try to refill entire ring */
        while (rx->fill_cnt != (rx->cnt + rx->mask + 1)) {
                idx = rx->fill_cnt & rx->mask;
                if (rx->page_offset + bytes <= MYRI10GE_ALLOC_SIZE) {
                        /* we can use part of previous page */
                        get_page(rx->page);
                } else {
                        /* we need a new page */
                        page =
                            alloc_pages(GFP_ATOMIC | __GFP_COMP,
                                        MYRI10GE_ALLOC_ORDER);
                        if (unlikely(page == NULL)) {
                                if (rx->fill_cnt - rx->cnt < 16)
                                        rx->watchdog_needed = 1;
                                return;
                        }

                        bus = pci_map_page(mgp->pdev, page, 0,
                                           MYRI10GE_ALLOC_SIZE,
                                           PCI_DMA_FROMDEVICE);
                        if (unlikely(pci_dma_mapping_error(mgp->pdev, bus))) {
                                __free_pages(page, MYRI10GE_ALLOC_ORDER);
                                if (rx->fill_cnt - rx->cnt < 16)
                                        rx->watchdog_needed = 1;
                                return;
                        }

                        rx->page = page;
                        rx->page_offset = 0;
                        rx->bus = bus;

                }
                rx->info[idx].page = rx->page;
                rx->info[idx].page_offset = rx->page_offset;
                /* note that this is the address of the start of the
                 * page */
                dma_unmap_addr_set(&rx->info[idx], bus, rx->bus);
                rx->shadow[idx].addr_low =
                    htonl(MYRI10GE_LOWPART_TO_U32(rx->bus) + rx->page_offset);
                rx->shadow[idx].addr_high =
                    htonl(MYRI10GE_HIGHPART_TO_U32(rx->bus));

                /* start next packet on a cacheline boundary */
                rx->page_offset += SKB_DATA_ALIGN(bytes);

#if MYRI10GE_ALLOC_SIZE > 4096
                /* don't cross a 4KB boundary */
                end_offset = rx->page_offset + bytes - 1;
                if ((unsigned)(rx->page_offset ^ end_offset) > 4095)
                        rx->page_offset = end_offset & ~4095;
#endif
                rx->fill_cnt++;

                /* copy 8 descriptors to the firmware at a time */
                if ((idx & 7) == 7) {
                        myri10ge_submit_8rx(&rx->lanai[idx - 7],
                                            &rx->shadow[idx - 7]);
                }
        }
}

static inline void
myri10ge_unmap_rx_page(struct pci_dev *pdev,
                       struct myri10ge_rx_buffer_state *info, int bytes)
{
        /* unmap the recvd page if we're the only or last user of it */
        if (bytes >= MYRI10GE_ALLOC_SIZE / 2 ||
            (info->page_offset + 2 * bytes) > MYRI10GE_ALLOC_SIZE) {
                pci_unmap_page(pdev, (dma_unmap_addr(info, bus)
                                      & ~(MYRI10GE_ALLOC_SIZE - 1)),
                               MYRI10GE_ALLOC_SIZE, PCI_DMA_FROMDEVICE);
        }
}

/*
 * GRO does not support acceleration of tagged vlan frames, and
 * this NIC does not support vlan tag offload, so we must pop
 * the tag ourselves to be able to achieve GRO performance that
 * is comparable to LRO.
 */

static inline void
myri10ge_vlan_rx(struct net_device *dev, void *addr, struct sk_buff *skb)
{
        u8 *va;
        struct vlan_ethhdr *veh;
        skb_frag_t *frag;
        __wsum vsum;

        va = addr;
        va += MXGEFW_PAD;
        veh = (struct vlan_ethhdr *)va;
        if ((dev->features & NETIF_F_HW_VLAN_CTAG_RX) ==
            NETIF_F_HW_VLAN_CTAG_RX &&
            veh->h_vlan_proto == htons(ETH_P_8021Q)) {
                /* fixup csum if needed */
                if (skb->ip_summed == CHECKSUM_COMPLETE) {
                        vsum = csum_partial(va + ETH_HLEN, VLAN_HLEN, 0);
                        skb->csum = csum_sub(skb->csum, vsum);
                }
                /* pop tag */
                __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), ntohs(veh->h_vlan_TCI));
                memmove(va + VLAN_HLEN, va, 2 * ETH_ALEN);
                skb->len -= VLAN_HLEN;
                skb->data_len -= VLAN_HLEN;
                frag = skb_shinfo(skb)->frags;
                skb_frag_off_add(frag, VLAN_HLEN);
                skb_frag_size_sub(frag, VLAN_HLEN);
        }
}

#define MYRI10GE_HLEN 64 /* Bytes to copy from page to skb linear memory */

static inline int
myri10ge_rx_done(struct myri10ge_slice_state *ss, int len, __wsum csum)
{
        struct myri10ge_priv *mgp = ss->mgp;
        struct sk_buff *skb;
        skb_frag_t *rx_frags;
        struct myri10ge_rx_buf *rx;
        int i, idx, remainder, bytes;
        struct pci_dev *pdev = mgp->pdev;
        struct net_device *dev = mgp->dev;
        u8 *va;

        if (len <= mgp->small_bytes) {
                rx = &ss->rx_small;
                bytes = mgp->small_bytes;
        } else {
                rx = &ss->rx_big;
                bytes = mgp->big_bytes;
        }

        len += MXGEFW_PAD;
        idx = rx->cnt & rx->mask;
        va = page_address(rx->info[idx].page) + rx->info[idx].page_offset;
        prefetch(va);

        skb = napi_get_frags(&ss->napi);
        if (unlikely(skb == NULL)) {
                ss->stats.rx_dropped++;
                for (i = 0, remainder = len; remainder > 0; i++) {
                        myri10ge_unmap_rx_page(pdev, &rx->info[idx], bytes);
                        put_page(rx->info[idx].page);
                        rx->cnt++;
                        idx = rx->cnt & rx->mask;
                        remainder -= MYRI10GE_ALLOC_SIZE;
                }
                return 0;
        }
        rx_frags = skb_shinfo(skb)->frags;
        /* Fill skb_frag_t(s) with data from our receive */
        for (i = 0, remainder = len; remainder > 0; i++) {
                myri10ge_unmap_rx_page(pdev, &rx->info[idx], bytes);
                skb_fill_page_desc(skb, i, rx->info[idx].page,
                                   rx->info[idx].page_offset,
                                   remainder < MYRI10GE_ALLOC_SIZE ?
                                   remainder : MYRI10GE_ALLOC_SIZE);
                rx->cnt++;
                idx = rx->cnt & rx->mask;
                remainder -= MYRI10GE_ALLOC_SIZE;
        }

        /* remove padding */
        skb_frag_off_add(&rx_frags[0], MXGEFW_PAD);
        skb_frag_size_sub(&rx_frags[0], MXGEFW_PAD);
        len -= MXGEFW_PAD;

        skb->len = len;
        skb->data_len = len;
        skb->truesize += len;
        if (dev->features & NETIF_F_RXCSUM) {
                skb->ip_summed = CHECKSUM_COMPLETE;
                skb->csum = csum;
        }
        myri10ge_vlan_rx(mgp->dev, va, skb);
        skb_record_rx_queue(skb, ss - &mgp->ss[0]);

        napi_gro_frags(&ss->napi);

        return 1;
}

static inline void
myri10ge_tx_done(struct myri10ge_slice_state *ss, int mcp_index)
{
        struct pci_dev *pdev = ss->mgp->pdev;
        struct myri10ge_tx_buf *tx = &ss->tx;
        struct netdev_queue *dev_queue;
        struct sk_buff *skb;
        int idx, len;

        while (tx->pkt_done != mcp_index) {
                idx = tx->done & tx->mask;
                skb = tx->info[idx].skb;

                /* Mark as free */
                tx->info[idx].skb = NULL;
                if (tx->info[idx].last) {
                        tx->pkt_done++;
                        tx->info[idx].last = 0;
                }
                tx->done++;
                len = dma_unmap_len(&tx->info[idx], len);
                dma_unmap_len_set(&tx->info[idx], len, 0);
                if (skb) {
                        ss->stats.tx_bytes += skb->len;
                        ss->stats.tx_packets++;
                        dev_consume_skb_irq(skb);
                        if (len)
                                pci_unmap_single(pdev,
                                                 dma_unmap_addr(&tx->info[idx],
                                                                bus), len,
                                                 PCI_DMA_TODEVICE);
                } else {
                        if (len)
                                pci_unmap_page(pdev,
                                               dma_unmap_addr(&tx->info[idx],
                                                              bus), len,
                                               PCI_DMA_TODEVICE);
                }
        }

        dev_queue = netdev_get_tx_queue(ss->dev, ss - ss->mgp->ss);
        /*
         * Make a minimal effort to prevent the NIC from polling an
         * idle tx queue.  If we can't get the lock we leave the queue
         * active. In this case, either a thread was about to start
         * using the queue anyway, or we lost a race and the NIC will
         * waste some of its resources polling an inactive queue for a
         * while.
         */

        if ((ss->mgp->dev->real_num_tx_queues > 1) &&
            __netif_tx_trylock(dev_queue)) {
                if (tx->req == tx->done) {
                        tx->queue_active = 0;
                        put_be32(htonl(1), tx->send_stop);
                        mb();
                }
                __netif_tx_unlock(dev_queue);
        }

        /* start the queue if we've stopped it */
        if (netif_tx_queue_stopped(dev_queue) &&
            tx->req - tx->done < (tx->mask >> 1) &&
            ss->mgp->running == MYRI10GE_ETH_RUNNING) {
                tx->wake_queue++;
                netif_tx_wake_queue(dev_queue);
        }
}

static inline int
myri10ge_clean_rx_done(struct myri10ge_slice_state *ss, int budget)
{
        struct myri10ge_rx_done *rx_done = &ss->rx_done;
        struct myri10ge_priv *mgp = ss->mgp;
        unsigned long rx_bytes = 0;
        unsigned long rx_packets = 0;
        unsigned long rx_ok;
        int idx = rx_done->idx;
        int cnt = rx_done->cnt;
        int work_done = 0;
        u16 length;
        __wsum checksum;

        while (rx_done->entry[idx].length != 0 && work_done < budget) {
                length = ntohs(rx_done->entry[idx].length);
                rx_done->entry[idx].length = 0;
                checksum = csum_unfold(rx_done->entry[idx].checksum);
                rx_ok = myri10ge_rx_done(ss, length, checksum);
                rx_packets += rx_ok;
                rx_bytes += rx_ok * (unsigned long)length;
                cnt++;
                idx = cnt & (mgp->max_intr_slots - 1);
                work_done++;
        }
        rx_done->idx = idx;
        rx_done->cnt = cnt;
        ss->stats.rx_packets += rx_packets;
        ss->stats.rx_bytes += rx_bytes;

        /* restock receive rings if needed */
        if (ss->rx_small.fill_cnt - ss->rx_small.cnt < myri10ge_fill_thresh)
                myri10ge_alloc_rx_pages(mgp, &ss->rx_small,
                                        mgp->small_bytes + MXGEFW_PAD, 0);
        if (ss->rx_big.fill_cnt - ss->rx_big.cnt < myri10ge_fill_thresh)
                myri10ge_alloc_rx_pages(mgp, &ss->rx_big, mgp->big_bytes, 0);

        return work_done;
}

static inline void myri10ge_check_statblock(struct myri10ge_priv *mgp)
{
        struct mcp_irq_data *stats = mgp->ss[0].fw_stats;

        if (unlikely(stats->stats_updated)) {
                unsigned link_up = ntohl(stats->link_up);
                if (mgp->link_state != link_up) {
                        mgp->link_state = link_up;

                        if (mgp->link_state == MXGEFW_LINK_UP) {
                                netif_info(mgp, link, mgp->dev, "link up\n");
                                netif_carrier_on(mgp->dev);
                                mgp->link_changes++;
                        } else {
                                netif_info(mgp, link, mgp->dev, "link %s\n",
                                           (link_up == MXGEFW_LINK_MYRINET ?
                                            "mismatch (Myrinet detected)" :
                                            "down"));
                                netif_carrier_off(mgp->dev);
                                mgp->link_changes++;
                        }
                }
                if (mgp->rdma_tags_available !=
                    ntohl(stats->rdma_tags_available)) {
                        mgp->rdma_tags_available =
                            ntohl(stats->rdma_tags_available);
                        netdev_warn(mgp->dev, "RDMA timed out! %d tags left\n",
                                    mgp->rdma_tags_available);
                }
                mgp->down_cnt += stats->link_down;
                if (stats->link_down)
                        wake_up(&mgp->down_wq);
        }
}

static int myri10ge_poll(struct napi_struct *napi, int budget)
{
        struct myri10ge_slice_state *ss =
            container_of(napi, struct myri10ge_slice_state, napi);
        int work_done;

#ifdef CONFIG_MYRI10GE_DCA
        if (ss->mgp->dca_enabled)
                myri10ge_update_dca(ss);
#endif
        /* process as many rx events as NAPI will allow */
        work_done = myri10ge_clean_rx_done(ss, budget);

        if (work_done < budget) {
                napi_complete_done(napi, work_done);
                put_be32(htonl(3), ss->irq_claim);
        }
        return work_done;
}

static irqreturn_t myri10ge_intr(int irq, void *arg)
{
        struct myri10ge_slice_state *ss = arg;
        struct myri10ge_priv *mgp = ss->mgp;
        struct mcp_irq_data *stats = ss->fw_stats;
        struct myri10ge_tx_buf *tx = &ss->tx;
        u32 send_done_count;
        int i;

        /* an interrupt on a non-zero receive-only slice is implicitly
         * valid  since MSI-X irqs are not shared */
        if ((mgp->dev->real_num_tx_queues == 1) && (ss != mgp->ss)) {
                napi_schedule(&ss->napi);
                return IRQ_HANDLED;
        }

        /* make sure it is our IRQ, and that the DMA has finished */
        if (unlikely(!stats->valid))
                return IRQ_NONE;

        /* low bit indicates receives are present, so schedule
         * napi poll handler */
        if (stats->valid & 1)
                napi_schedule(&ss->napi);

        if (!mgp->msi_enabled && !mgp->msix_enabled) {
                put_be32(0, mgp->irq_deassert);
                if (!myri10ge_deassert_wait)
                        stats->valid = 0;
                mb();
        } else
                stats->valid = 0;

        /* Wait for IRQ line to go low, if using INTx */
        i = 0;
        while (1) {
                i++;
                /* check for transmit completes and receives */
                send_done_count = ntohl(stats->send_done_count);
                if (send_done_count != tx->pkt_done)
                        myri10ge_tx_done(ss, (int)send_done_count);
                if (unlikely(i > myri10ge_max_irq_loops)) {
                        netdev_warn(mgp->dev, "irq stuck?\n");
                        stats->valid = 0;
                        schedule_work(&mgp->watchdog_work);
                }
                if (likely(stats->valid == 0))
                        break;
                cpu_relax();
                barrier();
        }

        /* Only slice 0 updates stats */
        if (ss == mgp->ss)
                myri10ge_check_statblock(mgp);

        put_be32(htonl(3), ss->irq_claim + 1);
        return IRQ_HANDLED;
}

static int
myri10ge_get_link_ksettings(struct net_device *netdev,
                            struct ethtool_link_ksettings *cmd)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);
        char *ptr;
        int i;

        cmd->base.autoneg = AUTONEG_DISABLE;
        cmd->base.speed = SPEED_10000;
        cmd->base.duplex = DUPLEX_FULL;

        /*
         * parse the product code to deterimine the interface type
         * (CX4, XFP, Quad Ribbon Fiber) by looking at the character
         * after the 3rd dash in the driver's cached copy of the
         * EEPROM's product code string.
         */
        ptr = mgp->product_code_string;
        if (ptr == NULL) {
                netdev_err(netdev, "Missing product code\n");
                return 0;
        }
        for (i = 0; i < 3; i++, ptr++) {
                ptr = strchr(ptr, '-');
                if (ptr == NULL) {
                        netdev_err(netdev, "Invalid product code %s\n",
                                   mgp->product_code_string);
                        return 0;
                }
        }
        if (*ptr == '2')
                ptr++;
        if (*ptr == 'R' || *ptr == 'Q' || *ptr == 'S') {
                /* We've found either an XFP, quad ribbon fiber, or SFP+ */
                cmd->base.port = PORT_FIBRE;
                ethtool_link_ksettings_add_link_mode(cmd, supported, FIBRE);
                ethtool_link_ksettings_add_link_mode(cmd, advertising, FIBRE);
        } else {
                cmd->base.port = PORT_OTHER;
        }

        return 0;
}

static void
myri10ge_get_drvinfo(struct net_device *netdev, struct ethtool_drvinfo *info)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);

        strlcpy(info->driver, "myri10ge", sizeof(info->driver));
        strlcpy(info->version, MYRI10GE_VERSION_STR, sizeof(info->version));
        strlcpy(info->fw_version, mgp->fw_version, sizeof(info->fw_version));
        strlcpy(info->bus_info, pci_name(mgp->pdev), sizeof(info->bus_info));
}

static int
myri10ge_get_coalesce(struct net_device *netdev, struct ethtool_coalesce *coal)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);

        coal->rx_coalesce_usecs = mgp->intr_coal_delay;
        return 0;
}

static int
myri10ge_set_coalesce(struct net_device *netdev, struct ethtool_coalesce *coal)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);

        mgp->intr_coal_delay = coal->rx_coalesce_usecs;
        put_be32(htonl(mgp->intr_coal_delay), mgp->intr_coal_delay_ptr);
        return 0;
}

static void
myri10ge_get_pauseparam(struct net_device *netdev,
                        struct ethtool_pauseparam *pause)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);

        pause->autoneg = 0;
        pause->rx_pause = mgp->pause;
        pause->tx_pause = mgp->pause;
}

static int
myri10ge_set_pauseparam(struct net_device *netdev,
                        struct ethtool_pauseparam *pause)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);

        if (pause->tx_pause != mgp->pause)
                return myri10ge_change_pause(mgp, pause->tx_pause);
        if (pause->rx_pause != mgp->pause)
                return myri10ge_change_pause(mgp, pause->rx_pause);
        if (pause->autoneg != 0)
                return -EINVAL;
        return 0;
}

static void
myri10ge_get_ringparam(struct net_device *netdev,
                       struct ethtool_ringparam *ring)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);

        ring->rx_mini_max_pending = mgp->ss[0].rx_small.mask + 1;
        ring->rx_max_pending = mgp->ss[0].rx_big.mask + 1;
        ring->rx_jumbo_max_pending = 0;
        ring->tx_max_pending = mgp->ss[0].tx.mask + 1;
        ring->rx_mini_pending = ring->rx_mini_max_pending;
        ring->rx_pending = ring->rx_max_pending;
        ring->rx_jumbo_pending = ring->rx_jumbo_max_pending;
        ring->tx_pending = ring->tx_max_pending;
}

static const char myri10ge_gstrings_main_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_boundary", "irq", "MSI", "MSIX",
        "read_dma_bw_MBs", "write_dma_bw_MBs", "read_write_dma_bw_MBs",
        "serial_number", "watchdog_resets",
#ifdef CONFIG_MYRI10GE_DCA
        "dca_capable_firmware", "dca_device_present",
#endif
        "link_changes", "link_up", "dropped_link_overflow",
        "dropped_link_error_or_filtered",
        "dropped_pause", "dropped_bad_phy", "dropped_bad_crc32",
        "dropped_unicast_filtered", "dropped_multicast_filtered",
        "dropped_runt", "dropped_overrun", "dropped_no_small_buffer",
        "dropped_no_big_buffer"
};

static const char myri10ge_gstrings_slice_stats[][ETH_GSTRING_LEN] = {
        "----------- slice ---------",
        "tx_pkt_start", "tx_pkt_done", "tx_req", "tx_done",
        "rx_small_cnt", "rx_big_cnt",
        "wake_queue", "stop_queue", "tx_linearized",
};

#define MYRI10GE_NET_STATS_LEN      21
#define MYRI10GE_MAIN_STATS_LEN  ARRAY_SIZE(myri10ge_gstrings_main_stats)
#define MYRI10GE_SLICE_STATS_LEN  ARRAY_SIZE(myri10ge_gstrings_slice_stats)

static void
myri10ge_get_strings(struct net_device *netdev, u32 stringset, u8 * data)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);
        int i;

        switch (stringset) {
        case ETH_SS_STATS:
                memcpy(data, *myri10ge_gstrings_main_stats,
                       sizeof(myri10ge_gstrings_main_stats));
                data += sizeof(myri10ge_gstrings_main_stats);
                for (i = 0; i < mgp->num_slices; i++) {
                        memcpy(data, *myri10ge_gstrings_slice_stats,
                               sizeof(myri10ge_gstrings_slice_stats));
                        data += sizeof(myri10ge_gstrings_slice_stats);
                }
                break;
        }
}

static int myri10ge_get_sset_count(struct net_device *netdev, int sset)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);

        switch (sset) {
        case ETH_SS_STATS:
                return MYRI10GE_MAIN_STATS_LEN +
                    mgp->num_slices * MYRI10GE_SLICE_STATS_LEN;
        default:
                return -EOPNOTSUPP;
        }
}

static void
myri10ge_get_ethtool_stats(struct net_device *netdev,
                           struct ethtool_stats *stats, u64 * data)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);
        struct myri10ge_slice_state *ss;
        struct rtnl_link_stats64 link_stats;
        int slice;
        int i;

        /* force stats update */
        memset(&link_stats, 0, sizeof(link_stats));
        (void)myri10ge_get_stats(netdev, &link_stats);
        for (i = 0; i < MYRI10GE_NET_STATS_LEN; i++)
                data[i] = ((u64 *)&link_stats)[i];

        data[i++] = (unsigned int)mgp->tx_boundary;
        data[i++] = (unsigned int)mgp->pdev->irq;
        data[i++] = (unsigned int)mgp->msi_enabled;
        data[i++] = (unsigned int)mgp->msix_enabled;
        data[i++] = (unsigned int)mgp->read_dma;
        data[i++] = (unsigned int)mgp->write_dma;
        data[i++] = (unsigned int)mgp->read_write_dma;
        data[i++] = (unsigned int)mgp->serial_number;
        data[i++] = (unsigned int)mgp->watchdog_resets;
#ifdef CONFIG_MYRI10GE_DCA
        data[i++] = (unsigned int)(mgp->ss[0].dca_tag != NULL);
        data[i++] = (unsigned int)(mgp->dca_enabled);
#endif
        data[i++] = (unsigned int)mgp->link_changes;

        /* firmware stats are useful only in the first slice */
        ss = &mgp->ss[0];
        data[i++] = (unsigned int)ntohl(ss->fw_stats->link_up);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_link_overflow);
        data[i++] =
            (unsigned int)ntohl(ss->fw_stats->dropped_link_error_or_filtered);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_pause);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_bad_phy);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_bad_crc32);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_unicast_filtered);
        data[i++] =
            (unsigned int)ntohl(ss->fw_stats->dropped_multicast_filtered);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_runt);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_overrun);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_no_small_buffer);
        data[i++] = (unsigned int)ntohl(ss->fw_stats->dropped_no_big_buffer);

        for (slice = 0; slice < mgp->num_slices; slice++) {
                ss = &mgp->ss[slice];
                data[i++] = slice;
                data[i++] = (unsigned int)ss->tx.pkt_start;
                data[i++] = (unsigned int)ss->tx.pkt_done;
                data[i++] = (unsigned int)ss->tx.req;
                data[i++] = (unsigned int)ss->tx.done;
                data[i++] = (unsigned int)ss->rx_small.cnt;
                data[i++] = (unsigned int)ss->rx_big.cnt;
                data[i++] = (unsigned int)ss->tx.wake_queue;
                data[i++] = (unsigned int)ss->tx.stop_queue;
                data[i++] = (unsigned int)ss->tx.linearized;
        }
}

static void myri10ge_set_msglevel(struct net_device *netdev, u32 value)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);
        mgp->msg_enable = value;
}

static u32 myri10ge_get_msglevel(struct net_device *netdev)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);
        return mgp->msg_enable;
}

/*
 * Use a low-level command to change the LED behavior. Rather than
 * blinking (which is the normal case), when identify is used, the
 * yellow LED turns solid.
 */
static int myri10ge_led(struct myri10ge_priv *mgp, int on)
{
        struct mcp_gen_header *hdr;
        struct device *dev = &mgp->pdev->dev;
        size_t hdr_off, pattern_off, hdr_len;
        u32 pattern = 0xfffffffe;

        /* find running firmware header */
        hdr_off = swab32(readl(mgp->sram + MCP_HEADER_PTR_OFFSET));
        if ((hdr_off & 3) || hdr_off + sizeof(*hdr) > mgp->sram_size) {
                dev_err(dev, "Running firmware has bad header offset (%d)\n",
                        (int)hdr_off);
                return -EIO;
        }
        hdr_len = swab32(readl(mgp->sram + hdr_off +
                               offsetof(struct mcp_gen_header, header_length)));
        pattern_off = hdr_off + offsetof(struct mcp_gen_header, led_pattern);
        if (pattern_off >= (hdr_len + hdr_off)) {
                dev_info(dev, "Firmware does not support LED identification\n");
                return -EINVAL;
        }
        if (!on)
                pattern = swab32(readl(mgp->sram + pattern_off + 4));
        writel(swab32(pattern), mgp->sram + pattern_off);
        return 0;
}

static int
myri10ge_phys_id(struct net_device *netdev, enum ethtool_phys_id_state state)
{
        struct myri10ge_priv *mgp = netdev_priv(netdev);
        int rc;

        switch (state) {
        case ETHTOOL_ID_ACTIVE:
                rc = myri10ge_led(mgp, 1);
                break;

        case ETHTOOL_ID_INACTIVE:
                rc =  myri10ge_led(mgp, 0);
                break;

        default:
                rc = -EINVAL;
        }

        return rc;
}

static const struct ethtool_ops myri10ge_ethtool_ops = {
        .get_drvinfo = myri10ge_get_drvinfo,
        .get_coalesce = myri10ge_get_coalesce,
        .set_coalesce = myri10ge_set_coalesce,
        .get_pauseparam = myri10ge_get_pauseparam,
        .set_pauseparam = myri10ge_set_pauseparam,
        .get_ringparam = myri10ge_get_ringparam,
        .get_link = ethtool_op_get_link,
        .get_strings = myri10ge_get_strings,
        .get_sset_count = myri10ge_get_sset_count,
        .get_ethtool_stats = myri10ge_get_ethtool_stats,
        .set_msglevel = myri10ge_set_msglevel,
        .get_msglevel = myri10ge_get_msglevel,
        .set_phys_id = myri10ge_phys_id,
        .get_link_ksettings = myri10ge_get_link_ksettings,
};

static int myri10ge_allocate_rings(struct myri10ge_slice_state *ss)
{
        struct myri10ge_priv *mgp = ss->mgp;
        struct myri10ge_cmd cmd;
        struct net_device *dev = mgp->dev;
        int tx_ring_size, rx_ring_size;
        int tx_ring_entries, rx_ring_entries;
        int i, slice, status;
        size_t bytes;

        /* get ring sizes */
        slice = ss - mgp->ss;
        cmd.data0 = slice;
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_SEND_RING_SIZE, &cmd, 0);
        tx_ring_size = cmd.data0;
        cmd.data0 = slice;
        status |= myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_RX_RING_SIZE, &cmd, 0);
        if (status != 0)
                return status;
        rx_ring_size = cmd.data0;

        tx_ring_entries = tx_ring_size / sizeof(struct mcp_kreq_ether_send);
        rx_ring_entries = rx_ring_size / sizeof(struct mcp_dma_addr);
        ss->tx.mask = tx_ring_entries - 1;
        ss->rx_small.mask = ss->rx_big.mask = rx_ring_entries - 1;

        status = -ENOMEM;

        /* allocate the host shadow rings */

        bytes = 8 + (MYRI10GE_MAX_SEND_DESC_TSO + 4)
            * sizeof(*ss->tx.req_list);
        ss->tx.req_bytes = kzalloc(bytes, GFP_KERNEL);
        if (ss->tx.req_bytes == NULL)
                goto abort_with_nothing;

        /* ensure req_list entries are aligned to 8 bytes */
        ss->tx.req_list = (struct mcp_kreq_ether_send *)
            ALIGN((unsigned long)ss->tx.req_bytes, 8);
        ss->tx.queue_active = 0;

        bytes = rx_ring_entries * sizeof(*ss->rx_small.shadow);
        ss->rx_small.shadow = kzalloc(bytes, GFP_KERNEL);
        if (ss->rx_small.shadow == NULL)
                goto abort_with_tx_req_bytes;

        bytes = rx_ring_entries * sizeof(*ss->rx_big.shadow);
        ss->rx_big.shadow = kzalloc(bytes, GFP_KERNEL);
        if (ss->rx_big.shadow == NULL)
                goto abort_with_rx_small_shadow;

        /* allocate the host info rings */

        bytes = tx_ring_entries * sizeof(*ss->tx.info);
        ss->tx.info = kzalloc(bytes, GFP_KERNEL);
        if (ss->tx.info == NULL)
                goto abort_with_rx_big_shadow;

        bytes = rx_ring_entries * sizeof(*ss->rx_small.info);
        ss->rx_small.info = kzalloc(bytes, GFP_KERNEL);
        if (ss->rx_small.info == NULL)
                goto abort_with_tx_info;

        bytes = rx_ring_entries * sizeof(*ss->rx_big.info);
        ss->rx_big.info = kzalloc(bytes, GFP_KERNEL);
        if (ss->rx_big.info == NULL)
                goto abort_with_rx_small_info;

        /* Fill the receive rings */
        ss->rx_big.cnt = 0;
        ss->rx_small.cnt = 0;
        ss->rx_big.fill_cnt = 0;
        ss->rx_small.fill_cnt = 0;
        ss->rx_small.page_offset = MYRI10GE_ALLOC_SIZE;
        ss->rx_big.page_offset = MYRI10GE_ALLOC_SIZE;
        ss->rx_small.watchdog_needed = 0;
        ss->rx_big.watchdog_needed = 0;
        if (mgp->small_bytes == 0) {
                ss->rx_small.fill_cnt = ss->rx_small.mask + 1;
        } else {
                myri10ge_alloc_rx_pages(mgp, &ss->rx_small,
                                        mgp->small_bytes + MXGEFW_PAD, 0);
        }

        if (ss->rx_small.fill_cnt < ss->rx_small.mask + 1) {
                netdev_err(dev, "slice-%d: alloced only %d small bufs\n",
                           slice, ss->rx_small.fill_cnt);
                goto abort_with_rx_small_ring;
        }

        myri10ge_alloc_rx_pages(mgp, &ss->rx_big, mgp->big_bytes, 0);
        if (ss->rx_big.fill_cnt < ss->rx_big.mask + 1) {
                netdev_err(dev, "slice-%d: alloced only %d big bufs\n",
                           slice, ss->rx_big.fill_cnt);
                goto abort_with_rx_big_ring;
        }

        return 0;

abort_with_rx_big_ring:
        for (i = ss->rx_big.cnt; i < ss->rx_big.fill_cnt; i++) {
                int idx = i & ss->rx_big.mask;
                myri10ge_unmap_rx_page(mgp->pdev, &ss->rx_big.info[idx],
                                       mgp->big_bytes);
                put_page(ss->rx_big.info[idx].page);
        }

abort_with_rx_small_ring:
        if (mgp->small_bytes == 0)
                ss->rx_small.fill_cnt = ss->rx_small.cnt;
        for (i = ss->rx_small.cnt; i < ss->rx_small.fill_cnt; i++) {
                int idx = i & ss->rx_small.mask;
                myri10ge_unmap_rx_page(mgp->pdev, &ss->rx_small.info[idx],
                                       mgp->small_bytes + MXGEFW_PAD);
                put_page(ss->rx_small.info[idx].page);
        }

        kfree(ss->rx_big.info);

abort_with_rx_small_info:
        kfree(ss->rx_small.info);

abort_with_tx_info:
        kfree(ss->tx.info);

abort_with_rx_big_shadow:
        kfree(ss->rx_big.shadow);

abort_with_rx_small_shadow:
        kfree(ss->rx_small.shadow);

abort_with_tx_req_bytes:
        kfree(ss->tx.req_bytes);
        ss->tx.req_bytes = NULL;
        ss->tx.req_list = NULL;

abort_with_nothing:
        return status;
}

static void myri10ge_free_rings(struct myri10ge_slice_state *ss)
{
        struct myri10ge_priv *mgp = ss->mgp;
        struct sk_buff *skb;
        struct myri10ge_tx_buf *tx;
        int i, len, idx;

        /* If not allocated, skip it */
        if (ss->tx.req_list == NULL)
                return;

        for (i = ss->rx_big.cnt; i < ss->rx_big.fill_cnt; i++) {
                idx = i & ss->rx_big.mask;
                if (i == ss->rx_big.fill_cnt - 1)
                        ss->rx_big.info[idx].page_offset = MYRI10GE_ALLOC_SIZE;
                myri10ge_unmap_rx_page(mgp->pdev, &ss->rx_big.info[idx],
                                       mgp->big_bytes);
                put_page(ss->rx_big.info[idx].page);
        }

        if (mgp->small_bytes == 0)
                ss->rx_small.fill_cnt = ss->rx_small.cnt;
        for (i = ss->rx_small.cnt; i < ss->rx_small.fill_cnt; i++) {
                idx = i & ss->rx_small.mask;
                if (i == ss->rx_small.fill_cnt - 1)
                        ss->rx_small.info[idx].page_offset =
                            MYRI10GE_ALLOC_SIZE;
                myri10ge_unmap_rx_page(mgp->pdev, &ss->rx_small.info[idx],
                                       mgp->small_bytes + MXGEFW_PAD);
                put_page(ss->rx_small.info[idx].page);
        }
        tx = &ss->tx;
        while (tx->done != tx->req) {
                idx = tx->done & tx->mask;
                skb = tx->info[idx].skb;

                /* Mark as free */
                tx->info[idx].skb = NULL;
                tx->done++;
                len = dma_unmap_len(&tx->info[idx], len);
                dma_unmap_len_set(&tx->info[idx], len, 0);
                if (skb) {
                        ss->stats.tx_dropped++;
                        dev_kfree_skb_any(skb);
                        if (len)
                                pci_unmap_single(mgp->pdev,
                                                 dma_unmap_addr(&tx->info[idx],
                                                                bus), len,
                                                 PCI_DMA_TODEVICE);
                } else {
                        if (len)
                                pci_unmap_page(mgp->pdev,
                                               dma_unmap_addr(&tx->info[idx],
                                                              bus), len,
                                               PCI_DMA_TODEVICE);
                }
        }
        kfree(ss->rx_big.info);

        kfree(ss->rx_small.info);

        kfree(ss->tx.info);

        kfree(ss->rx_big.shadow);

        kfree(ss->rx_small.shadow);

        kfree(ss->tx.req_bytes);
        ss->tx.req_bytes = NULL;
        ss->tx.req_list = NULL;
}

static int myri10ge_request_irq(struct myri10ge_priv *mgp)
{
        struct pci_dev *pdev = mgp->pdev;
        struct myri10ge_slice_state *ss;
        struct net_device *netdev = mgp->dev;
        int i;
        int status;

        mgp->msi_enabled = 0;
        mgp->msix_enabled = 0;
        status = 0;
        if (myri10ge_msi) {
                if (mgp->num_slices > 1) {
                        status = pci_enable_msix_range(pdev, mgp->msix_vectors,
                                        mgp->num_slices, mgp->num_slices);
                        if (status < 0) {
                                dev_err(&pdev->dev,
                                        "Error %d setting up MSI-X\n", status);
                                return status;
                        }
                        mgp->msix_enabled = 1;
                }
                if (mgp->msix_enabled == 0) {
                        status = pci_enable_msi(pdev);
                        if (status != 0) {
                                dev_err(&pdev->dev,
                                        "Error %d setting up MSI; falling back to xPIC\n",
                                        status);
                        } else {
                                mgp->msi_enabled = 1;
                        }
                }
        }
        if (mgp->msix_enabled) {
                for (i = 0; i < mgp->num_slices; i++) {
                        ss = &mgp->ss[i];
                        snprintf(ss->irq_desc, sizeof(ss->irq_desc),
                                 "%s:slice-%d", netdev->name, i);
                        status = request_irq(mgp->msix_vectors[i].vector,
                                             myri10ge_intr, 0, ss->irq_desc,
                                             ss);
                        if (status != 0) {
                                dev_err(&pdev->dev,
                                        "slice %d failed to allocate IRQ\n", i);
                                i--;
                                while (i >= 0) {
                                        free_irq(mgp->msix_vectors[i].vector,
                                                 &mgp->ss[i]);
                                        i--;
                                }
                                pci_disable_msix(pdev);
                                return status;
                        }
                }
        } else {
                status = request_irq(pdev->irq, myri10ge_intr, IRQF_SHARED,
                                     mgp->dev->name, &mgp->ss[0]);
                if (status != 0) {
                        dev_err(&pdev->dev, "failed to allocate IRQ\n");
                        if (mgp->msi_enabled)
                                pci_disable_msi(pdev);
                }
        }
        return status;
}

static void myri10ge_free_irq(struct myri10ge_priv *mgp)
{
        struct pci_dev *pdev = mgp->pdev;
        int i;

        if (mgp->msix_enabled) {
                for (i = 0; i < mgp->num_slices; i++)
                        free_irq(mgp->msix_vectors[i].vector, &mgp->ss[i]);
        } else {
                free_irq(pdev->irq, &mgp->ss[0]);
        }
        if (mgp->msi_enabled)
                pci_disable_msi(pdev);
        if (mgp->msix_enabled)
                pci_disable_msix(pdev);
}

static int myri10ge_get_txrx(struct myri10ge_priv *mgp, int slice)
{
        struct myri10ge_cmd cmd;
        struct myri10ge_slice_state *ss;
        int status;

        ss = &mgp->ss[slice];
        status = 0;
        if (slice == 0 || (mgp->dev->real_num_tx_queues > 1)) {
                cmd.data0 = slice;
                status = myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_SEND_OFFSET,
                                           &cmd, 0);
                ss->tx.lanai = (struct mcp_kreq_ether_send __iomem *)
                    (mgp->sram + cmd.data0);
        }
        cmd.data0 = slice;
        status |= myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_SMALL_RX_OFFSET,
                                    &cmd, 0);
        ss->rx_small.lanai = (struct mcp_kreq_ether_recv __iomem *)
            (mgp->sram + cmd.data0);

        cmd.data0 = slice;
        status |= myri10ge_send_cmd(mgp, MXGEFW_CMD_GET_BIG_RX_OFFSET, &cmd, 0);
        ss->rx_big.lanai = (struct mcp_kreq_ether_recv __iomem *)
            (mgp->sram + cmd.data0);

        ss->tx.send_go = (__iomem __be32 *)
            (mgp->sram + MXGEFW_ETH_SEND_GO + 64 * slice);
        ss->tx.send_stop = (__iomem __be32 *)
            (mgp->sram + MXGEFW_ETH_SEND_STOP + 64 * slice);
        return status;

}

static int myri10ge_set_stats(struct myri10ge_priv *mgp, int slice)
{
        struct myri10ge_cmd cmd;
        struct myri10ge_slice_state *ss;
        int status;

        ss = &mgp->ss[slice];
        cmd.data0 = MYRI10GE_LOWPART_TO_U32(ss->fw_stats_bus);
        cmd.data1 = MYRI10GE_HIGHPART_TO_U32(ss->fw_stats_bus);
        cmd.data2 = sizeof(struct mcp_irq_data) | (slice << 16);
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_STATS_DMA_V2, &cmd, 0);
        if (status == -ENOSYS) {
                dma_addr_t bus = ss->fw_stats_bus;
                if (slice != 0)
                        return -EINVAL;
                bus += offsetof(struct mcp_irq_data, send_done_count);
                cmd.data0 = MYRI10GE_LOWPART_TO_U32(bus);
                cmd.data1 = MYRI10GE_HIGHPART_TO_U32(bus);
                status = myri10ge_send_cmd(mgp,
                                           MXGEFW_CMD_SET_STATS_DMA_OBSOLETE,
                                           &cmd, 0);
                /* Firmware cannot support multicast without STATS_DMA_V2 */
                mgp->fw_multicast_support = 0;
        } else {
                mgp->fw_multicast_support = 1;
        }
        return 0;
}

static int myri10ge_open(struct net_device *dev)
{
        struct myri10ge_slice_state *ss;
        struct myri10ge_priv *mgp = netdev_priv(dev);
        struct myri10ge_cmd cmd;
        int i, status, big_pow2, slice;
        u8 __iomem *itable;

        if (mgp->running != MYRI10GE_ETH_STOPPED)
                return -EBUSY;

        mgp->running = MYRI10GE_ETH_STARTING;
        status = myri10ge_reset(mgp);
        if (status != 0) {
                netdev_err(dev, "failed reset\n");
                goto abort_with_nothing;
        }

        if (mgp->num_slices > 1) {
                cmd.data0 = mgp->num_slices;
                cmd.data1 = MXGEFW_SLICE_INTR_MODE_ONE_PER_SLICE;
                if (mgp->dev->real_num_tx_queues > 1)
                        cmd.data1 |= MXGEFW_SLICE_ENABLE_MULTIPLE_TX_QUEUES;
                status = myri10ge_send_cmd(mgp, MXGEFW_CMD_ENABLE_RSS_QUEUES,
                                           &cmd, 0);
                if (status != 0) {
                        netdev_err(dev, "failed to set number of slices\n");
                        goto abort_with_nothing;
                }
                /* setup the indirection table */
                cmd.data0 = mgp->num_slices;
                status = myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_RSS_TABLE_SIZE,
                                           &cmd, 0);

                status |= myri10ge_send_cmd(mgp,
                                            MXGEFW_CMD_GET_RSS_TABLE_OFFSET,
                                            &cmd, 0);
                if (status != 0) {
                        netdev_err(dev, "failed to setup rss tables\n");
                        goto abort_with_nothing;
                }

                /* just enable an identity mapping */
                itable = mgp->sram + cmd.data0;
                for (i = 0; i < mgp->num_slices; i++)
                        __raw_writeb(i, &itable[i]);

                cmd.data0 = 1;
                cmd.data1 = myri10ge_rss_hash;
                status = myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_RSS_ENABLE,
                                           &cmd, 0);
                if (status != 0) {
                        netdev_err(dev, "failed to enable slices\n");
                        goto abort_with_nothing;
                }
        }

        status = myri10ge_request_irq(mgp);
        if (status != 0)
                goto abort_with_nothing;

        /* decide what small buffer size to use.  For good TCP rx
         * performance, it is important to not receive 1514 byte
         * frames into jumbo buffers, as it confuses the socket buffer
         * accounting code, leading to drops and erratic performance.
         */

        if (dev->mtu <= ETH_DATA_LEN)
                /* enough for a TCP header */
                mgp->small_bytes = (128 > SMP_CACHE_BYTES)
                    ? (128 - MXGEFW_PAD)
                    : (SMP_CACHE_BYTES - MXGEFW_PAD);
        else
                /* enough for a vlan encapsulated ETH_DATA_LEN frame */
                mgp->small_bytes = VLAN_ETH_FRAME_LEN;

        /* Override the small buffer size? */
        if (myri10ge_small_bytes >= 0)
                mgp->small_bytes = myri10ge_small_bytes;

        /* Firmware needs the big buff size as a power of 2.  Lie and
         * tell him the buffer is larger, because we only use 1
         * buffer/pkt, and the mtu will prevent overruns.
         */
        big_pow2 = dev->mtu + ETH_HLEN + VLAN_HLEN + MXGEFW_PAD;
        if (big_pow2 < MYRI10GE_ALLOC_SIZE / 2) {
                while (!is_power_of_2(big_pow2))
                        big_pow2++;
                mgp->big_bytes = dev->mtu + ETH_HLEN + VLAN_HLEN + MXGEFW_PAD;
        } else {
                big_pow2 = MYRI10GE_ALLOC_SIZE;
                mgp->big_bytes = big_pow2;
        }

        /* setup the per-slice data structures */
        for (slice = 0; slice < mgp->num_slices; slice++) {
                ss = &mgp->ss[slice];

                status = myri10ge_get_txrx(mgp, slice);
                if (status != 0) {
                        netdev_err(dev, "failed to get ring sizes or locations\n");
                        goto abort_with_rings;
                }
                status = myri10ge_allocate_rings(ss);
                if (status != 0)
                        goto abort_with_rings;

                /* only firmware which supports multiple TX queues
                 * supports setting up the tx stats on non-zero
                 * slices */
                if (slice == 0 || mgp->dev->real_num_tx_queues > 1)
                        status = myri10ge_set_stats(mgp, slice);
                if (status) {
                        netdev_err(dev, "Couldn't set stats DMA\n");
                        goto abort_with_rings;
                }

                /* must happen prior to any irq */
                napi_enable(&(ss)->napi);
        }

        /* now give firmware buffers sizes, and MTU */
        cmd.data0 = dev->mtu + ETH_HLEN + VLAN_HLEN;
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_MTU, &cmd, 0);
        cmd.data0 = mgp->small_bytes;
        status |=
            myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_SMALL_BUFFER_SIZE, &cmd, 0);
        cmd.data0 = big_pow2;
        status |=
            myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_BIG_BUFFER_SIZE, &cmd, 0);
        if (status) {
                netdev_err(dev, "Couldn't set buffer sizes\n");
                goto abort_with_rings;
        }

        /*
         * Set Linux style TSO mode; this is needed only on newer
         *  firmware versions.  Older versions default to Linux
         *  style TSO
         */
        cmd.data0 = 0;
        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_SET_TSO_MODE, &cmd, 0);
        if (status && status != -ENOSYS) {
                netdev_err(dev, "Couldn't set TSO mode\n");
                goto abort_with_rings;
        }

        mgp->link_state = ~0U;
        mgp->rdma_tags_available = 15;

        status = myri10ge_send_cmd(mgp, MXGEFW_CMD_ETHERNET_UP, &cmd, 0);
        if (status) {
                netdev_err(dev, "Couldn't bring up link\n");
                goto abort_with_rings;
        }

        mgp->running = MYRI10GE_ETH_RUNNING;
        mgp->watchdog_timer.expires = jiffies + myri10ge_watchdog_timeout * HZ;
        add_timer(&mgp->watchdog_timer);
        netif_tx_wake_all_queues(dev);

        return 0;

abort_with_rings:
        while (slice) {
                slice--;
                napi_disable(&mgp->ss[slice].napi);
        }
        for (i = 0; i < mgp->num_slices; i++)
                myri10ge_free_rings(&mgp->ss[i]);

        myri10ge_free_irq(mgp);

abort_with_nothing:
        mgp->running = MYRI10GE_ETH_STOPPED;
        return -ENOMEM;
}

static int myri10ge_close(struct net_device *dev)
{
        struct myri10ge_priv *mgp = netdev_priv(dev);
        struct myri10ge_cmd cmd;
        int status, old_down_cnt;
        int i;

        if (mgp->running != MYRI10GE_ETH_RUNNING)
                return 0;

        if (mgp->ss[0].tx.req_bytes == NULL)
                return 0;

        del_timer_sync(&mgp->watchdog_timer);
        mgp->running = MYRI10GE_ETH_STOPPING;
        for (i = 0; i < mgp->num_slices; i++)
                napi_disable(&mgp->ss[i].napi);

        netif_carrier_off(dev);

        netif_tx_stop_all_queues(dev);
        if (mgp->rebooted == 0) {
                old_down_cnt = mgp->down_cnt;
                mb();
                status =
                    myri10ge_send_cmd(mgp, MXGEFW_CMD_ETHERNET_DOWN, &cmd, 0);
                if (status)
                        netdev_err(dev, "Couldn't bring down link\n");

                wait_event_timeout(mgp->down_wq, old_down_cnt != mgp->down_cnt,
                                   HZ);
                if (old_down_cnt == mgp->down_cnt)
                        netdev_err(dev, "never got down irq\n");
        }
        netif_tx_disable(dev);
        myri10ge_free_irq(mgp);
        for (i = 0; i < mgp->num_slices; i++)
                myri10ge_free_rings(&mgp->ss[i]);

        mgp->running = MYRI10GE_ETH_STOPPED;
        return 0;
}

/* copy an array of struct mcp_kreq_ether_send's to the mcp.  Copy
 * backwards one at a time and handle ring wraps */

static inline void
myri10ge_submit_req_backwards(struct myri10ge_tx_buf *tx,
                              struct mcp_kreq_ether_send *src, int cnt)
{
        int idx, starting_slot;
        starting_slot = tx->req;
        while (cnt > 1) {
                cnt--;
                idx = (starting_slot + cnt) & tx->mask;
                myri10ge_pio_copy(&tx->lanai[idx], &src[cnt], sizeof(*src));
                mb();
        }
}

/*
 * copy an array of struct mcp_kreq_ether_send's to the mcp.  Copy
 * at most 32 bytes at a time, so as to avoid involving the software
 * pio handler in the nic.   We re-write the first segment's flags
 * to mark them valid only after writing the entire chain.
 */

static inline void
myri10ge_submit_req(struct myri10ge_tx_buf *tx, struct mcp_kreq_ether_send *src,
                    int cnt)
{
        int idx, i;
        struct mcp_kreq_ether_send __iomem *dstp, *dst;
        struct mcp_kreq_ether_send *srcp;
        u8 last_flags;

        idx = tx->req & tx->mask;

        last_flags = src->flags;
        src->flags = 0;
        mb();
        dst = dstp = &tx->lanai[idx];
        srcp = src;

        if ((idx + cnt) < tx->mask) {
                for (i = 0; i < (cnt - 1); i += 2) {
                        myri10ge_pio_copy(dstp, srcp, 2 * sizeof(*src));
                        mb();   /* force write every 32 bytes */
                        srcp += 2;
                        dstp += 2;
                }
        } else {
                /* submit all but the first request, and ensure
                 * that it is submitted below */
                myri10ge_submit_req_backwards(tx, src, cnt);
                i = 0;
        }
        if (i < cnt) {
                /* submit the first request */
                myri10ge_pio_copy(dstp, srcp, sizeof(*src));
                mb();           /* barrier before setting valid flag */
        }

        /* re-write the last 32-bits with the valid flags */
        src->flags = last_flags;
        put_be32(*((__be32 *) src + 3), (__be32 __iomem *) dst + 3);
        tx->req += cnt;
        mb();
}

static void myri10ge_unmap_tx_dma(struct myri10ge_priv *mgp,
                                  struct myri10ge_tx_buf *tx, int idx)
{
        unsigned int len;
        int last_idx;

        /* Free any DMA resources we've alloced and clear out the skb slot */
        last_idx = (idx + 1) & tx->mask;
        idx = tx->req & tx->mask;
        do {
                len = dma_unmap_len(&tx->info[idx], len);
                if (len) {
                        if (tx->info[idx].skb != NULL)
                                pci_unmap_single(mgp->pdev,
                                                 dma_unmap_addr(&tx->info[idx],
                                                                bus), len,
                                                 PCI_DMA_TODEVICE);
                        else
                                pci_unmap_page(mgp->pdev,
                                               dma_unmap_addr(&tx->info[idx],
                                                              bus), len,
                                               PCI_DMA_TODEVICE);
                        dma_unmap_len_set(&tx->info[idx], len, 0);
                        tx->info[idx].skb = NULL;
                }
                idx = (idx + 1) & tx->mask;
        } while (idx != last_idx);
}

/*
 * Transmit a packet.  We need to split the packet so that a single
 * segment does not cross myri10ge->tx_boundary, so this makes segment
 * counting tricky.  So rather than try to count segments up front, we
 * just give up if there are too few segments to hold a reasonably
 * fragmented packet currently available.  If we run
 * out of segments while preparing a packet for DMA, we just linearize
 * it and try again.
 */

static netdev_tx_t myri10ge_xmit(struct sk_buff *skb,
                                       struct net_device *dev)
{
        struct myri10ge_priv *mgp = netdev_priv(dev);
        struct myri10ge_slice_state *ss;
        struct mcp_kreq_ether_send *req;
        struct myri10ge_tx_buf *tx;
        skb_frag_t *frag;
        struct netdev_queue *netdev_queue;
        dma_addr_t bus;
        u32 low;
        __be32 high_swapped;
        unsigned int len;
        int idx, avail, frag_cnt, frag_idx, count, mss, max_segments;
        u16 pseudo_hdr_offset, cksum_offset, queue;
        int cum_len, seglen, boundary, rdma_count;
        u8 flags, odd_flag;

        queue = skb_get_queue_mapping(skb);
        ss = &mgp->ss[queue];
        netdev_queue = netdev_get_tx_queue(mgp->dev, queue);
        tx = &ss->tx;

again:
        req = tx->req_list;
        avail = tx->mask - 1 - (tx->req - tx->done);

        mss = 0;
        max_segments = MXGEFW_MAX_SEND_DESC;

        if (skb_is_gso(skb)) {
                mss = skb_shinfo(skb)->gso_size;
                max_segments = MYRI10GE_MAX_SEND_DESC_TSO;
        }

        if ((unlikely(avail < max_segments))) {
                /* we are out of transmit resources */
                tx->stop_queue++;
                netif_tx_stop_queue(netdev_queue);
                return NETDEV_TX_BUSY;
        }

        /* Setup checksum offloading, if needed */
        cksum_offset = 0;
        pseudo_hdr_offset = 0;
        odd_flag = 0;
        flags = (MXGEFW_FLAGS_NO_TSO | MXGEFW_FLAGS_FIRST);
        if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
                cksum_offset = skb_checksum_start_offset(skb);
                pseudo_hdr_offset = cksum_offset + skb->csum_offset;
                /* If the headers are excessively large, then we must
                 * fall back to a software checksum */
                if (unlikely(!mss && (cksum_offset > 255 ||
                                      pseudo_hdr_offset > 127))) {
                        if (skb_checksum_help(skb))
                                goto drop;
                        cksum_offset = 0;
                        pseudo_hdr_offset = 0;
                } else {
                        odd_flag = MXGEFW_FLAGS_ALIGN_ODD;
                        flags |= MXGEFW_FLAGS_CKSUM;
                }
        }

        cum_len = 0;

        if (mss) {              /* TSO */
                /* this removes any CKSUM flag from before */
                flags = (MXGEFW_FLAGS_TSO_HDR | MXGEFW_FLAGS_FIRST);

                /* negative cum_len signifies to the
                 * send loop that we are still in the
                 * header portion of the TSO packet.
                 * TSO header can be at most 1KB long */
                cum_len = -(skb_transport_offset(skb) + tcp_hdrlen(skb));

                /* for IPv6 TSO, the checksum offset stores the
                 * TCP header length, to save the firmware from
                 * the need to parse the headers */
                if (skb_is_gso_v6(skb)) {
                        cksum_offset = tcp_hdrlen(skb);
                        /* Can only handle headers <= max_tso6 long */
                        if (unlikely(-cum_len > mgp->max_tso6))
                                return myri10ge_sw_tso(skb, dev);
                }
                /* for TSO, pseudo_hdr_offset holds mss.
                 * The firmware figures out where to put
                 * the checksum by parsing the header. */
                pseudo_hdr_offset = mss;
        } else
                /* Mark small packets, and pad out tiny packets */
        if (skb->len <= MXGEFW_SEND_SMALL_SIZE) {
                flags |= MXGEFW_FLAGS_SMALL;

                /* pad frames to at least ETH_ZLEN bytes */
                if (eth_skb_pad(skb)) {
                        /* The packet is gone, so we must
                         * return 0 */
                        ss->stats.tx_dropped += 1;
                        return NETDEV_TX_OK;
                }
        }

        /* map the skb for DMA */
        len = skb_headlen(skb);
        bus = pci_map_single(mgp->pdev, skb->data, len, PCI_DMA_TODEVICE);
        if (unlikely(pci_dma_mapping_error(mgp->pdev, bus)))
                goto drop;

        idx = tx->req & tx->mask;
        tx->info[idx].skb = skb;
        dma_unmap_addr_set(&tx->info[idx], bus, bus);
        dma_unmap_len_set(&tx->info[idx], len, len);

        frag_cnt = skb_shinfo(skb)->nr_frags;
        frag_idx = 0;
        count = 0;
        rdma_count = 0;

        /* "rdma_count" is the number of RDMAs belonging to the
         * current packet BEFORE the current send request. For
         * non-TSO packets, this is equal to "count".
         * For TSO packets, rdma_count needs to be reset
         * to 0 after a segment cut.
         *
         * The rdma_count field of the send request is
         * the number of RDMAs of the packet starting at
         * that request. For TSO send requests with one ore more cuts
         * in the middle, this is the number of RDMAs starting
         * after the last cut in the request. All previous
         * segments before the last cut implicitly have 1 RDMA.
         *
         * Since the number of RDMAs is not known beforehand,
         * it must be filled-in retroactively - after each
         * segmentation cut or at the end of the entire packet.
         */

        while (1) {
                /* Break the SKB or Fragment up into pieces which
                 * do not cross mgp->tx_boundary */
                low = MYRI10GE_LOWPART_TO_U32(bus);
                high_swapped = htonl(MYRI10GE_HIGHPART_TO_U32(bus));
                while (len) {
                        u8 flags_next;
                        int cum_len_next;

                        if (unlikely(count == max_segments))
                                goto abort_linearize;

                        boundary =
                            (low + mgp->tx_boundary) & ~(mgp->tx_boundary - 1);
                        seglen = boundary - low;
                        if (seglen > len)
                                seglen = len;
                        flags_next = flags & ~MXGEFW_FLAGS_FIRST;
                        cum_len_next = cum_len + seglen;
                        if (mss) {      /* TSO */
                                (req - rdma_count)->rdma_count = rdma_count + 1;

                                if (likely(cum_len >= 0)) {     /* payload */
                                        int next_is_first, chop;

                                        chop = (cum_len_next > mss);
                                        cum_len_next = cum_len_next % mss;
                                        next_is_first = (cum_len_next == 0);
                                        flags |= chop * MXGEFW_FLAGS_TSO_CHOP;
                                        flags_next |= next_is_first *
                                            MXGEFW_FLAGS_FIRST;
                                        rdma_count |= -(chop | next_is_first);
                                        rdma_count += chop & ~next_is_first;
                                } else if (likely(cum_len_next >= 0)) { /* header ends */
                                        int small;

                                        rdma_count = -1;
                                        cum_len_next = 0;
                                        seglen = -cum_len;
                                        small = (mss <= MXGEFW_SEND_SMALL_SIZE);
                                        flags_next = MXGEFW_FLAGS_TSO_PLD |
                                            MXGEFW_FLAGS_FIRST |
                                            (small * MXGEFW_FLAGS_SMALL);
                                }
                        }
                        req->addr_high = high_swapped;
                        req->addr_low = htonl(low);
                        req->pseudo_hdr_offset = htons(pseudo_hdr_offset);
                        req->pad = 0;   /* complete solid 16-byte block; does this matter? */
                        req->rdma_count = 1;
                        req->length = htons(seglen);
                        req->cksum_offset = cksum_offset;
                        req->flags = flags | ((cum_len & 1) * odd_flag);

                        low += seglen;
                        len -= seglen;
                        cum_len = cum_len_next;
                        flags = flags_next;
                        req++;
                        count++;
                        rdma_count++;
                        if (cksum_offset != 0 && !(mss && skb_is_gso_v6(skb))) {
                                if (unlikely(cksum_offset > seglen))
                                        cksum_offset -= seglen;
                                else
                                        cksum_offset = 0;
                        }
                }
                if (frag_idx == frag_cnt)
                        break;

                /* map next fragment for DMA */
                frag = &skb_shinfo(skb)->frags[frag_idx];
                frag_idx++;
                len = skb_frag_size(frag);
                bus = skb_frag_dma_map(&mgp->pdev->dev, frag, 0, len,
                                       DMA_TO_DEVICE);
                if (unlikely(pci_dma_mapping_error(mgp->pdev, bus))) {
                        myri10ge_unmap_tx_dma(mgp, tx, idx);
                        goto drop;
                }
                idx = (count + tx->req) & tx->mask;
                dma_unmap_addr_set(&tx->info[idx], bus, bus);
                dma_unmap_len_set(&tx->info[idx], len, len);
        }

        (req - rdma_count)->rdma_count = rdma_count;
        if (mss)
                do {
                        req--;
                        req->flags |= MXGEFW_FLAGS_TSO_LAST;
                } while (!(req->flags & (MXGEFW_FLAGS_TSO_CHOP |
                                         MXGEFW_FLAGS_FIRST)));
        idx = ((count - 1) + tx->req) & tx->mask;
        tx->info[idx].last = 1;
        myri10ge_submit_req(tx, tx->req_list, count);
        /* if using multiple tx queues, make sure NIC polls the
         * current slice */
        if ((mgp->dev->real_num_tx_queues > 1) && tx->queue_active == 0) {
                tx->queue_active = 1;
                put_be32(htonl(1), tx->send_go);
                mb();
        }
        tx->pkt_start++;
        if ((avail - count) < MXGEFW_MAX_SEND_DESC) {
                tx->stop_queue++;
                netif_tx_stop_queue(netdev_queue);
        }
        return NETDEV_TX_OK;

abort_linearize:
        myri10ge_unmap_tx_dma(mgp, tx, idx);

        if (skb_is_gso(skb)) {
                netdev_err(mgp->dev, "TSO but wanted to linearize?!?!?\n");
                goto drop;
        }

        if (skb_linearize(skb))
                goto drop;

        tx->linearized++;
        goto again;

drop:
        dev_kfree_skb_any(skb);
        ss->stats.tx_dropped += 1;
        return NETDEV_TX_OK;

}

static netdev_tx_t myri10ge_sw_tso(struct sk_buff *skb,
                                         struct net_device *dev)
{
        struct sk_buff *segs, *curr;
        struct myri10ge_priv *mgp = netdev_priv(dev);
        struct myri10ge_slice_state *ss;
        netdev_tx_t status;

        segs = skb_gso_segment(skb, dev->features & ~NETIF_F_TSO6);
        if (IS_ERR(segs))
                goto drop;

        while (segs) {
                curr = segs;
                segs = segs->next;
                curr->next = NULL;
                status = myri10ge_xmit(curr, dev);
                if (status != 0) {
                        dev_kfree_skb_any(curr);
                        if (segs != NULL) {
                                curr = segs;
                                segs = segs->next;
                                curr->next = NULL;
                                dev_kfree_skb_any(segs);
                        }
                        goto drop;
                }
        }
        dev_kfree_skb_any(skb);
        return NETDEV_TX_OK;

drop:
        ss = &mgp->ss[skb_get_queue_mapping(skb)];
        dev_kfree_skb_any(skb);
        ss->stats.tx_dropped += 1;
        return NETDEV_TX_OK;
}

static void myri10ge_get_stats(struct net_device *dev,
                               struct rtnl_link_stats64 *stats)
{
        const struct myri10ge_priv *mgp = netdev_priv(dev);
        const struct myri10ge_slice_netstats *slice_stats;
        int i;

        for (i = 0; i < mgp->num_slices; i++) {
                slice_stats = &mgp->ss[i].stats;
                stats->rx_packets += slice_stats->rx_packets;
                stats->tx_packets += slice_stats->tx_packets;
                stats->rx_bytes += slice_stats->rx_bytes;
                stats->tx_bytes += slice_stats->tx_bytes;
                stats->rx_dropped += slice_stats->rx_dropped;
                stats->tx_dropped += slice_stats->tx_dropped;
        }
}

static void myri10ge_set_multicast_list(struct net_device *dev)
{
        struct myri10ge_priv *mgp = netdev_priv(dev);
        struct myri10ge_cmd cmd;
        struct netdev_hw_addr *ha;
        __be32 data[2] = { 0, 0 };
        int err;

        /* can be called from atomic contexts,
         * pass 1 to force atomicity in myri10ge_send_cmd() */
        myri10ge_change_promisc(mgp, dev->flags & IFF_PROMISC, 1);

        /* This firmware is known to not support multicast */
        if (!mgp->fw_multicast_support)
                return;

        /* Disable multicast filtering */

        err = myri10ge_send_cmd(mgp, MXGEFW_ENABLE_ALLMULTI, &cmd, 1);
        if (err != 0) {
                netdev_err(dev, "Failed MXGEFW_ENABLE_ALLMULTI, error status: %d\n",
                           err);
                goto abort;
        }

        if ((dev->flags & IFF_ALLMULTI) || mgp->adopted_rx_filter_bug) {
                /* request to disable multicast filtering, so quit here */
                return;
        }

        /* Flush the filters */

        err = myri10ge_send_cmd(mgp, MXGEFW_LEAVE_ALL_MULTICAST_GROUPS,
                                &cmd, 1);
        if (err != 0) {
                netdev_err(dev, "Failed MXGEFW_LEAVE_ALL_MULTICAST_GROUPS, error status: %d\n",
                           err);
                goto abort;
        }

        /* Walk the multicast list, and add each address */
        netdev_for_each_mc_addr(ha, dev) {
                memcpy(data, &ha->addr, ETH_ALEN);
                cmd.data0 = ntohl(data[0]);
                cmd.data1 = ntohl(data[1]);
                err = myri10ge_send_cmd(mgp, MXGEFW_JOIN_MULTICAST_GROUP,
                                        &cmd, 1);

                if (err != 0) {
                        netdev_err(dev, "Failed MXGEFW_JOIN_MULTICAST_GROUP, error status:%d %pM\n",
                                   err, ha->addr);
                        goto abort;
                }