PMD是Poll Mode Driver的缩写，即基于用户态的轮询机制的驱动

在不考虑vfio的情况下，PMD的结构图如下

 　　虽然PMD是在用户态实现设备驱动，但还是依赖于内核提供的策略。其中uio模块，是内核提供的用户态驱动框架，而igb_uio是DPDK kit中拥有与uio交互，bind指定网卡的内核模块;

　　当使用DPDK脚本dpdk-devbind来bind网卡时，会通过sysfs与内核交互，让内核使用指定驱动来匹配网卡。具体的行为向/sys/bus/pci/devices/(pci id)/driver_override写入指定驱动名称，或者向/sys/bus/pci/drivers/igb_uio(驱动名称）/new_id写入要绑定网卡的PCI ID。前者是配置设备，让其选择驱动。后者是是配置驱动，让其支持新的PCI设备。按照内核的文档https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-bus-pci，这两个动作都会促使驱动bind新设备。

　　但是在dpdk-devbind脚本中，还是通过向/sys/bus/pci/drivers/igb_uio(驱动名称）/bind写入pci id来保证bind;

　　当使用igb_uio bind指定设备后，内核会调用igb_uio注册的struct pci_driver的probe函数，即igbuio_pci_probe;

其会调用uio_register_device，注册uio设备

打开uio设备

 应用层DPDK已经可以使用uio设备了。DPDK的应用层代码，会打开uioX设备，在函数pci_uio_alloc_resource中；

 　　当open对应的uio设备时，对应的内核操作为uio_open，其又会调用igb_uio的open函数，流程图如下

 igb_uio的默认中断模式为RTE_INTR_MODE_MSIX，在igbuio_pci_enable_interrupts的关键代码如下

static int
igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
{int err = 0;switch (igbuio_intr_mode_preferred) {case RTE_INTR_MODE_MSIX:/* Only 1 msi-x vector needed */
#ifndef HAVE_ALLOC_IRQ_VECTORSmsix_entry.entry = 0;if (pci_enable_msix(udev->pdev, &msix_entry, 1) == 0) {dev_dbg(&udev->pdev->dev, "using MSI-X");udev->info.irq_flags = IRQF_NO_THREAD;udev->info.irq = msix_entry.vector;udev->mode = RTE_INTR_MODE_MSIX;break;}
#elseif (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSIX) == 1) {dev_dbg(&udev->pdev->dev, "using MSI-X");udev->info.irq_flags = IRQF_NO_THREAD;udev->info.irq = pci_irq_vector(udev->pdev, 0);udev->mode = RTE_INTR_MODE_MSIX;break;}
#endifdefault:dev_err(&udev->pdev->dev, "invalid IRQ mode %u",igbuio_intr_mode_preferred);udev->info.irq = UIO_IRQ_NONE;err = -EINVAL;}if (udev->info.irq != UIO_IRQ_NONE)err = request_irq(udev->info.irq, igbuio_pci_irqhandler,udev->info.irq_flags, udev->info.name,udev);dev_info(&udev->pdev->dev, "uio device registered with irq %ld\n",udev->info.irq);return err;
}

 　　当打开uio设备时，igb_uio注册了一个中断。这时大家应该有个疑问，PMD不是用户态轮询设备吗？为什么还要申请中断，注册中断处理函数呢？这是因为，即使应用层可以通过uio来实现设备驱动，但是设备的某些事件还是需要内核进行响应，然后通知应用层；相当于中断的上半部 和下半部

 上半部中断服务函数： 主要通知一个event到user比如： 唤醒在idev->wait等待队列中的task

/*** This is interrupt handler which will check if the interrupt is for the right device.* If yes, disable it here and will be enable later.*/
static irqreturn_t
igbuio_pci_irqhandler(int irq, void *dev_id)
{struct rte_uio_pci_dev *udev = (struct rte_uio_pci_dev *)dev_id;struct uio_info *info = &udev->info;/* Legacy mode need to mask in hardware */if (udev->mode == RTE_INTR_MODE_LEGACY &&!pci_check_and_mask_intx(udev->pdev))return IRQ_NONE;uio_event_notify(info);/* Message signal mode, no share IRQ and automasked */return IRQ_HANDLED;
}

当DPDK的app启动时，会进行EAL初始化，如下图：

以ixgbe驱动为例详细说明：

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RTE_PMD_REGISTER_PCI(net_ixgbe, rte_ixgbe_pmd);#define RTE_PMD_EXPORT_NAME(name, idx) \
static const char RTE_PMD_EXPORT_NAME_ARRAY(this_pmd_name, idx) \
__attribute__((used)) = RTE_STR(name)/** Helper for PCI device registration from driver (eth, crypto) instance */
#define RTE_PMD_REGISTER_PCI(nm, pci_drv) \
RTE_INIT(pciinitfn_ ##nm) \
{\(pci_drv).driver.name = RTE_STR(nm);\rte_pci_register(&pci_drv); \
} \
RTE_PMD_EXPORT_NAME(nm, __COUNTER__)/* register a driver */
void
rte_pci_register(struct rte_pci_driver *driver)
{TAILQ_INSERT_TAIL(&rte_pci_bus.driver_list, driver, next);driver->bus = &rte_pci_bus;
}

　　　　RTE_PMD_REGISTER_PCI为dpdk定义的宏，使用了GNU C提供的“__attribute__（constructor）”机制，使得注册设备驱动的过程在main函数执行之前完成。 
　　这样就有了设备驱动类型、设备驱动的初始化函数

 使用attribute的constructor属性，在MAIN函数执行前，就执行pmd_driver_register()函数，将pmd_igb_drv驱动挂到全局dev_driver_list链表上。

2、通过读取/sys/bus/pci/devices/目录下的信息，扫描当前系统的PCI设备，并初始化，并按照PCI地址从大到小的顺序挂在到pci_debice_list上。

3、rte_bus_probe------>rte_eal_pci_probe_one_driver();通过比对PCI_ID的vendor_id、device_id、subsystem_vendor_id、subsystem_device_id四个字段判断pci设备和pci驱动是否匹配。

　　PCI设备和PCI驱动匹配后，调用pci_map_device()函数为该PCI设备创建map resource；　　pci_uio_map_resource()函数为pci设备在虚拟地址空间映射pci资源，后续直接通过操作内存来操作pci设备

4、rte_bus_probe---------->调用rte_eth_dev_create 以及 eth_ixgbe_pci_probe()初始化PCI设备； 并通过eth_ixgbe_dev_init 函数分配一个网卡设备，并在全局数组rte_eth_dev_data[]中为网卡设备的数据域分配空间。

　　同时初始化网卡设备。首先设置网卡设备的操作函数集，以及收包、发包函数

/* Launch threads, called at application init(). */
int
rte_eal_init(int argc, char **argv)
{int i, fctret, ret;pthread_t thread_id;static rte_atomic32_t run_once = RTE_ATOMIC32_INIT(0);const char *p;static char logid[PATH_MAX];char cpuset[RTE_CPU_AFFINITY_STR_LEN];char thread_name[RTE_MAX_THREAD_NAME_LEN];/* checks if the machine is adequate */if (!rte_cpu_is_supported()) {rte_eal_init_alert("unsupported cpu type.");rte_errno = ENOTSUP;return -1;}//操作静态局部变量run_once确保函数只执行一次if (!rte_atomic32_test_and_set(&run_once)) {rte_eal_init_alert("already called initialization.");rte_errno = EALREADY;return -1;}
//dpdk: EAL init args: -c 3 -n 4 --file-prefix vpp --master-lcore 0p = strrchr(argv[0], '/');strlcpy(logid, p ? p + 1 : argv[0], sizeof(logid));thread_id = pthread_self();//获取主线程的线程ID
//初始化结构体struct internal_configeal_reset_internal_config(&internal_config);/* set log level as early as possible设置log level */eal_log_level_parse(argc, argv);//赋值全局结构struct lcore_configif (rte_eal_cpu_init() < 0) {//赋值全局结构struct lcore_configrte_eal_init_alert("Cannot detect lcores.");rte_errno = ENOTSUP;return -1;}fctret = eal_parse_args(argc, argv);if (fctret < 0) {rte_eal_init_alert("Invalid 'command line' arguments.");rte_errno = EINVAL;rte_atomic32_clear(&run_once);return -1;}if (eal_plugins_init() < 0) {//EAL的“-d”选项可以指定需要载入的动态链接库)rte_eal_init_alert("Cannot init plugins\n");rte_errno = EINVAL;rte_atomic32_clear(&run_once);return -1;}if (eal_option_device_parse()) {rte_errno = ENODEV;rte_atomic32_clear(&run_once);return -1;}rte_config_init();if (rte_eal_intr_init() < 0) {rte_eal_init_alert("Cannot init interrupt-handling thread\n");return -1;}/* Put mp channel init before bus scan so that we can init the vdev* bus through mp channel in the secondary process before the bus scan.*/if (rte_mp_channel_init() < 0) {rte_eal_init_alert("failed to init mp channel\n");if (rte_eal_process_type() == RTE_PROC_PRIMARY) {rte_errno = EFAULT;return -1;}}if (rte_bus_scan()) {//scan 扫描设备的device信息///sys/bus/pci/devices”目录下的所有pci地址，逐个获取对应的pci地址、pci id、sriov使能时的vf个数、亲和的numa、设备地址空间、驱动类型等rte_eal_init_alert("Cannot scan the buses for devices\n");rte_errno = ENODEV;rte_atomic32_clear(&run_once);return -1;}/* autodetect the iova mapping mode (default is iova_pa) */rte_eal_get_configuration()->iova_mode = rte_bus_get_iommu_class();/* Workaround for KNI which requires physical address to work */if (rte_eal_get_configuration()->iova_mode == RTE_IOVA_VA &&rte_eal_check_module("rte_kni") == 1) {rte_eal_get_configuration()->iova_mode = RTE_IOVA_PA;RTE_LOG(WARNING, EAL,"Some devices want IOVA as VA but PA will be used because.. ""KNI module inserted\n");}if (internal_config.no_hugetlbfs == 0) {/* rte_config isn't initialized yet */ret = internal_config.process_type == RTE_PROC_PRIMARY ?eal_hugepage_info_init() :eal_hugepage_info_read();if (ret < 0) {rte_eal_init_alert("Cannot get hugepage information.");rte_errno = EACCES;rte_atomic32_clear(&run_once);return -1;}}if (internal_config.memory == 0 && internal_config.force_sockets == 0) {if (internal_config.no_hugetlbfs)internal_config.memory = MEMSIZE_IF_NO_HUGE_PAGE;}if (internal_config.vmware_tsc_map == 1) {
#ifdef RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORTrte_cycles_vmware_tsc_map = 1;RTE_LOG (DEBUG, EAL, "Using VMWARE TSC MAP, ""you must have monitor_control.pseudo_perfctr = TRUE\n");
#elseRTE_LOG (WARNING, EAL, "Ignoring --vmware-tsc-map because ""RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORT is not set\n");
#endif}rte_srand(rte_rdtsc());if (rte_eal_log_init(logid, internal_config.syslog_facility) < 0) {rte_eal_init_alert("Cannot init logging.");rte_errno = ENOMEM;rte_atomic32_clear(&run_once);return -1;}#ifdef VFIO_PRESENTif (rte_eal_vfio_setup() < 0) {rte_eal_init_alert("Cannot init VFIO\n");rte_errno = EAGAIN;rte_atomic32_clear(&run_once);return -1;}
#endif/* in secondary processes, memory init may allocate additional fbarrays* not present in primary processes, so to avoid any potential issues,* initialize memzones first.*/if (rte_eal_memzone_init() < 0) {rte_eal_init_alert("Cannot init memzone\n");rte_errno = ENODEV;return -1;}if (rte_eal_memory_init() < 0) {rte_eal_init_alert("Cannot init memory\n");rte_errno = ENOMEM;return -1;}/* the directories are locked during eal_hugepage_info_init */eal_hugedirs_unlock();if (rte_eal_malloc_heap_init() < 0) {rte_eal_init_alert("Cannot init malloc heap\n");rte_errno = ENODEV;return -1;}if (rte_eal_tailqs_init() < 0) {rte_eal_init_alert("Cannot init tail queues for objects\n");rte_errno = EFAULT;return -1;}if (rte_eal_alarm_init() < 0) {rte_eal_init_alert("Cannot init interrupt-handling thread\n");/* rte_eal_alarm_init sets rte_errno on failure. */return -1;}if (rte_eal_timer_init() < 0) {rte_eal_init_alert("Cannot init HPET or TSC timers\n");rte_errno = ENOTSUP;return -1;}eal_check_mem_on_local_socket();eal_thread_init_master(rte_config.master_lcore);ret = eal_thread_dump_affinity(cpuset, sizeof(cpuset));RTE_LOG(DEBUG, EAL, "Master lcore %u is ready (tid=%x;cpuset=[%s%s])\n",rte_config.master_lcore, (int)thread_id, cpuset,ret == 0 ? "" : "...");RTE_LCORE_FOREACH_SLAVE(i) {/** create communication pipes between master thread* and children*/if (pipe(lcore_config[i].pipe_master2slave) < 0)rte_panic("Cannot create pipe\n");if (pipe(lcore_config[i].pipe_slave2master) < 0)rte_panic("Cannot create pipe\n");lcore_config[i].state = WAIT;/* create a thread for each lcore */ret = pthread_create(&lcore_config[i].thread_id, NULL,eal_thread_loop, NULL);if (ret != 0)rte_panic("Cannot create thread\n");/* Set thread_name for aid in debugging. */snprintf(thread_name, sizeof(thread_name),"lcore-slave-%d", i);ret = rte_thread_setname(lcore_config[i].thread_id,thread_name);if (ret != 0)RTE_LOG(DEBUG, EAL,"Cannot set name for lcore thread\n");}/** Launch a dummy function on all slave lcores, so that master lcore* knows they are all ready when this function returns.*/rte_eal_mp_remote_launch(sync_func, NULL, SKIP_MASTER);rte_eal_mp_wait_lcore();/* initialize services so vdevs register service during bus_probe. */ret = rte_service_init();if (ret) {rte_eal_init_alert("rte_service_init() failed\n");rte_errno = ENOEXEC;return -1;}/* Probe all the buses and devices/drivers on them /* 所有的 dirver 都会register a driver  void rte_pci_register(struct rte_pci_driver *driver){  TAILQ_INSERT_TAIL(&rte_pci_bus.driver_list, driver, next);driver->bus = &rte_pci_bus;*/／＊遍历pci_device_list和pci_driver_list链表，根据PCI_ID，将pci_device与pci_driver绑定，并调用pci_driver的　probe函数初始化PCI设备＊／if (rte_bus_probe()) {//对应 rte_pci_probe  函数 --->pci_probe_all_drivers//--AILQ_FOREACH(p, &(rte_pci_bus.driver_list), next) ---->rte_pci_probe_one_driver
//----rte_pci_map_device  &&　　dr->probe(dr, dev);
//PCI设备和PCI驱动匹配后，调用pci_map_device()函数为该PCI设备创建map resourcerte_eal_init_alert("Cannot probe devices\n");rte_errno = ENOTSUP;return -1;}#ifdef VFIO_PRESENT/* Register mp action after probe() so that we got enough info */if (rte_vfio_is_enabled("vfio") && vfio_mp_sync_setup() < 0)return -1;
#endif/* initialize default service/lcore mappings and start running. Ignore* -ENOTSUP, as it indicates no service coremask passed to EAL.*/ret = rte_service_start_with_defaults();if (ret < 0 && ret != -ENOTSUP) {rte_errno = ENOEXEC;return -1;}rte_eal_mcfg_complete();return fctret;
}

/*
读取/sys/bus/pci/devices/0000\:00\:09.0/uio/uio0/maps/map0/目录下的文件，获取UIO设备的map resource。并将其记录在struct pci_map数据结构中。
检查PCI设备和UIO设备在内存总线上的物理地址是否一致。如果一致，对/dev/uioID文件mmap一段内存空间，并将其记录在pci_map->addr和rte_pci_device->mem_resource[].addr中将所有UIO设备的resource信息都记录在struct mapped_pci_resource数据结构中，并挂到全局链表uio_res_list上
*//* Map pci device */
int
rte_pci_map_device(struct rte_pci_device *dev)
{int ret = -1;/* try mapping the NIC resources using VFIO if it exists */switch (dev->kdrv) {case RTE_KDRV_VFIO:
#ifdef VFIO_PRESENTif (pci_vfio_is_enabled())ret = pci_vfio_map_resource(dev);
#endifbreak;case RTE_KDRV_IGB_UIO:case RTE_KDRV_UIO_GENERIC:if (rte_eal_using_phys_addrs()) {/* map resources for devices that use uio */ret = pci_uio_map_resource(dev);}break;default:RTE_LOG(DEBUG, EAL,"  Not managed by a supported kernel driver, skipped\n");ret = 1;break;}return ret;
}/* map the PCI resource of a PCI device in virtual memory */
int
pci_uio_map_resource(struct rte_pci_device *dev)
{int i, map_idx = 0, ret;uint64_t phaddr;struct mapped_pci_resource *uio_res = NULL;struct mapped_pci_res_list *uio_res_list =RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list);dev->intr_handle.fd = -1;dev->intr_handle.uio_cfg_fd = -1;/* secondary processes - use already recorded details */if (rte_eal_process_type() != RTE_PROC_PRIMARY)return pci_uio_map_secondary(dev);/* allocate uio resource  open 打开要管理的uio 设备*/ret = pci_uio_alloc_resource(dev, &uio_res);if (ret)return ret;/* DPDK还需要把PCI设备的BAR映射到应用层Map all BARs    */for (i = 0; i != PCI_MAX_RESOURCE; i++) {/* skip empty BAR */phaddr = dev->mem_resource[i].phys_addr;if (phaddr == 0)continue;ret = pci_uio_map_resource_by_index(dev, i,uio_res, map_idx);if (ret)goto error;map_idx++;}uio_res->nb_maps = map_idx;TAILQ_INSERT_TAIL(uio_res_list, uio_res, next);return 0;
error:for (i = 0; i < map_idx; i++) {pci_unmap_resource(uio_res->maps[i].addr,(size_t)uio_res->maps[i].size);rte_free(uio_res->maps[i].path);}pci_uio_free_resource(dev, uio_res);return -1;
}int
pci_uio_alloc_resource(struct rte_pci_device *dev,struct mapped_pci_resource **uio_res)
{char devname[PATH_MAX]; /* contains the /dev/uioX */struct rte_pci_addr *loc;loc = &dev->addr;snprintf(devname, sizeof(devname), "/dev/uio@pci:%u:%u:%u",dev->addr.bus, dev->addr.devid, dev->addr.function);if (access(devname, O_RDWR) < 0) {RTE_LOG(WARNING, EAL, "  "PCI_PRI_FMT" not managed by UIO driver, ""skipping\n", loc->domain, loc->bus, loc->devid, loc->function);return 1;}/* save fd if in primary process 
初始化PCI设备的中断句柄。*/dev->intr_handle.fd = open(devname, O_RDWR);if (dev->intr_handle.fd < 0) {RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",devname, strerror(errno));goto error;}dev->intr_handle.type = RTE_INTR_HANDLE_UIO;/* allocate the mapping details for secondary processes*/*uio_res = rte_zmalloc("UIO_RES", sizeof(**uio_res), 0);if (*uio_res == NULL) {RTE_LOG(ERR, EAL,"%s(): cannot store uio mmap details\n", __func__);goto error;}snprintf((*uio_res)->path, sizeof((*uio_res)->path), "%s", devname);memcpy(&(*uio_res)->pci_addr, &dev->addr, sizeof((*uio_res)->pci_addr));return 0;error:pci_uio_free_resource(dev, *uio_res);return -1;
}

4、rte_bus_probe---------->调用rte_eth_dev_create 以及 eth_ixgbe_pci_probe()初始化PCI设备； 并通过eth_ixgbe_dev_init 函数分配一个网卡设备，并在全局数组rte_eth_dev_data[]中为网卡设备的数据域分配空间。

　　同时初始化网卡设备。首先设置网卡设备的操作函数集，以及收包、发包函数

注册中断处理函数。

rte_intr_callback_register(&(pci_dev->intr_handle),eth_igb_interrupt_handler, (void *)eth_dev);

int __rte_experimental
rte_eth_dev_create(struct rte_device *device, const char *name,size_t priv_data_size,ethdev_bus_specific_init ethdev_bus_specific_init,void *bus_init_params,ethdev_init_t ethdev_init, void *init_params)
{struct rte_eth_dev *ethdev;int retval;RTE_FUNC_PTR_OR_ERR_RET(*ethdev_init, -EINVAL);if (rte_eal_process_type() == RTE_PROC_PRIMARY) {//在全局数组rte_eth_devices[]中分配一个网卡设备。并在全局数组rte_eth_dev_data[]中为网卡设备的数据域分配空间。ethdev = rte_eth_dev_allocate(name);if (!ethdev)return -ENODEV;if (priv_data_size) {ethdev->data->dev_private = rte_zmalloc_socket(name, priv_data_size, RTE_CACHE_LINE_SIZE,device->numa_node);if (!ethdev->data->dev_private) {RTE_LOG(ERR, EAL, "failed to allocate private data");retval = -ENOMEM;goto data_alloc_failed;}}} else {ethdev = rte_eth_dev_attach_secondary(name);if (!ethdev) {RTE_LOG(ERR, EAL, "secondary process attach failed, ""ethdev doesn't exist");return  -ENODEV;}}ethdev->device = device;if (ethdev_bus_specific_init) {retval = ethdev_bus_specific_init(ethdev, bus_init_params);if (retval) {RTE_LOG(ERR, EAL,"ethdev bus specific initialisation failed");goto probe_failed;}}retval = ethdev_init(ethdev, init_params);if (retval) {RTE_LOG(ERR, EAL, "ethdev initialisation failed");goto probe_failed;}rte_eth_dev_probing_finish(ethdev);return retval;
probe_failed:/* free ports private data if primary process */if (rte_eal_process_type() == RTE_PROC_PRIMARY)rte_free(ethdev->data->dev_private);data_alloc_failed:rte_eth_dev_release_port(ethdev);return retval;
}/** This function is based on code in ixgbe_attach() in base/ixgbe.c.* It returns 0 on success.*/
static int
eth_ixgbe_dev_init(struct rte_eth_dev *eth_dev, void *init_params __rte_unused)
{struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(eth_dev);struct rte_intr_handle *intr_handle = &pci_dev->intr_handle;struct ixgbe_hw *hw =IXGBE_DEV_PRIVATE_TO_HW(eth_dev->data->dev_private);struct ixgbe_vfta *shadow_vfta =IXGBE_DEV_PRIVATE_TO_VFTA(eth_dev->data->dev_private);struct ixgbe_hwstrip *hwstrip =IXGBE_DEV_PRIVATE_TO_HWSTRIP_BITMAP(eth_dev->data->dev_private);struct ixgbe_dcb_config *dcb_config =IXGBE_DEV_PRIVATE_TO_DCB_CFG(eth_dev->data->dev_private);struct ixgbe_filter_info *filter_info =IXGBE_DEV_PRIVATE_TO_FILTER_INFO(eth_dev->data->dev_private);struct ixgbe_bw_conf *bw_conf =IXGBE_DEV_PRIVATE_TO_BW_CONF(eth_dev->data->dev_private);uint32_t ctrl_ext;uint16_t csum;int diag, i;PMD_INIT_FUNC_TRACE();//设置网卡设备的操作函数集，以及收包、发包函数eth_dev->dev_ops = &ixgbe_eth_dev_ops;eth_dev->rx_pkt_burst = &ixgbe_recv_pkts;eth_dev->tx_pkt_burst = &ixgbe_xmit_pkts;eth_dev->tx_pkt_prepare = &ixgbe_prep_pkts;/** For secondary processes, we don't initialise any further as primary* has already done this work. Only check we don't need a different* RX and TX function.*/if (rte_eal_process_type() != RTE_PROC_PRIMARY) {struct ixgbe_tx_queue *txq;/* TX queue function in primary, set by last queue initialized* Tx queue may not initialized by primary process*/if (eth_dev->data->tx_queues) {txq = eth_dev->data->tx_queues[eth_dev->data->nb_tx_queues-1];ixgbe_set_tx_function(eth_dev, txq);} else {/* Use default TX function if we get here */PMD_INIT_LOG(NOTICE, "No TX queues configured yet. ""Using default TX function.");}ixgbe_set_rx_function(eth_dev);return 0;}rte_eth_copy_pci_info(eth_dev, pci_dev);/* Vendor and Device ID need to be set before init of shared code */hw->device_id = pci_dev->id.device_id;hw->vendor_id = pci_dev->id.vendor_id;hw->hw_addr = (void *)pci_dev->mem_resource[0].addr;hw->allow_unsupported_sfp = 1;/* Initialize the shared code (base driver) */
#ifdef RTE_LIBRTE_IXGBE_BYPASSdiag = ixgbe_bypass_init_shared_code(hw);
#elsediag = ixgbe_init_shared_code(hw);
#endif /* RTE_LIBRTE_IXGBE_BYPASS */if (diag != IXGBE_SUCCESS) {PMD_INIT_LOG(ERR, "Shared code init failed: %d", diag);return -EIO;}/* pick up the PCI bus settings for reporting later */ixgbe_get_bus_info(hw);/* Unlock any pending hardware semaphore */ixgbe_swfw_lock_reset(hw);#ifdef RTE_LIBRTE_SECURITY/* Initialize security_ctx only for primary process*/if (ixgbe_ipsec_ctx_create(eth_dev))return -ENOMEM;
#endif/* Initialize DCB configuration*/memset(dcb_config, 0, sizeof(struct ixgbe_dcb_config));ixgbe_dcb_init(hw, dcb_config);/* Get Hardware Flow Control setting */hw->fc.requested_mode = ixgbe_fc_full;hw->fc.current_mode = ixgbe_fc_full;hw->fc.pause_time = IXGBE_FC_PAUSE;for (i = 0; i < IXGBE_DCB_MAX_TRAFFIC_CLASS; i++) {hw->fc.low_water[i] = IXGBE_FC_LO;hw->fc.high_water[i] = IXGBE_FC_HI;}hw->fc.send_xon = 1;/* Make sure we have a good EEPROM before we read from it */diag = ixgbe_validate_eeprom_checksum(hw, &csum);if (diag != IXGBE_SUCCESS) {PMD_INIT_LOG(ERR, "The EEPROM checksum is not valid: %d", diag);return -EIO;}#ifdef RTE_LIBRTE_IXGBE_BYPASSdiag = ixgbe_bypass_init_hw(hw);
#elsediag = ixgbe_init_hw(hw);
#endif /* RTE_LIBRTE_IXGBE_BYPASS *//** Devices with copper phys will fail to initialise if ixgbe_init_hw()* is called too soon after the kernel driver unbinding/binding occurs.* The failure occurs in ixgbe_identify_phy_generic() for all devices,* but for non-copper devies, ixgbe_identify_sfp_module_generic() is* also called. See ixgbe_identify_phy_82599(). The reason for the* failure is not known, and only occuts when virtualisation features* are disabled in the bios. A delay of 100ms  was found to be enough by* trial-and-error, and is doubled to be safe.*/if (diag && (hw->mac.ops.get_media_type(hw) == ixgbe_media_type_copper)) {rte_delay_ms(200);diag = ixgbe_init_hw(hw);}if (diag == IXGBE_ERR_SFP_NOT_PRESENT)diag = IXGBE_SUCCESS;if (diag == IXGBE_ERR_EEPROM_VERSION) {PMD_INIT_LOG(ERR, "This device is a pre-production adapter/""LOM.  Please be aware there may be issues associated ""with your hardware.");PMD_INIT_LOG(ERR, "If you are experiencing problems ""please contact your Intel or hardware representative ""who provided you with this hardware.");} else if (diag == IXGBE_ERR_SFP_NOT_SUPPORTED)PMD_INIT_LOG(ERR, "Unsupported SFP+ Module");if (diag) {PMD_INIT_LOG(ERR, "Hardware Initialization Failure: %d", diag);return -EIO;}/* Reset the hw statistics */ixgbe_dev_stats_reset(eth_dev);/* disable interrupt */ixgbe_disable_intr(hw);/* reset mappings for queue statistics hw counters*/ixgbe_reset_qstat_mappings(hw);/* Allocate memory for storing MAC addresses */eth_dev->data->mac_addrs = rte_zmalloc("ixgbe", ETHER_ADDR_LEN *hw->mac.num_rar_entries, 0);if (eth_dev->data->mac_addrs == NULL) {PMD_INIT_LOG(ERR,"Failed to allocate %u bytes needed to store ""MAC addresses",ETHER_ADDR_LEN * hw->mac.num_rar_entries);return -ENOMEM;}/* Copy the permanent MAC address */ether_addr_copy((struct ether_addr *) hw->mac.perm_addr,ð_dev->data->mac_addrs[0]);/* Allocate memory for storing hash filter MAC addresses */eth_dev->data->hash_mac_addrs = rte_zmalloc("ixgbe", ETHER_ADDR_LEN *IXGBE_VMDQ_NUM_UC_MAC, 0);if (eth_dev->data->hash_mac_addrs == NULL) {PMD_INIT_LOG(ERR,"Failed to allocate %d bytes needed to store MAC addresses",ETHER_ADDR_LEN * IXGBE_VMDQ_NUM_UC_MAC);return -ENOMEM;}/* initialize the vfta */memset(shadow_vfta, 0, sizeof(*shadow_vfta));/* initialize the hw strip bitmap*/memset(hwstrip, 0, sizeof(*hwstrip));/* initialize PF if max_vfs not zero */ixgbe_pf_host_init(eth_dev);ctrl_ext = IXGBE_READ_REG(hw, IXGBE_CTRL_EXT);/* let hardware know driver is loaded */ctrl_ext |= IXGBE_CTRL_EXT_DRV_LOAD;/* Set PF Reset Done bit so PF/VF Mail Ops can work */ctrl_ext |= IXGBE_CTRL_EXT_PFRSTD;IXGBE_WRITE_REG(hw, IXGBE_CTRL_EXT, ctrl_ext);IXGBE_WRITE_FLUSH(hw);if (ixgbe_is_sfp(hw) && hw->phy.sfp_type != ixgbe_sfp_type_not_present)PMD_INIT_LOG(DEBUG, "MAC: %d, PHY: %d, SFP+: %d",(int) hw->mac.type, (int) hw->phy.type,(int) hw->phy.sfp_type);elsePMD_INIT_LOG(DEBUG, "MAC: %d, PHY: %d",(int) hw->mac.type, (int) hw->phy.type);PMD_INIT_LOG(DEBUG, "port %d vendorID=0x%x deviceID=0x%x",eth_dev->data->port_id, pci_dev->id.vendor_id,pci_dev->id.device_id);
//注册中断处理函数。rte_intr_callback_register(intr_handle,ixgbe_dev_interrupt_handler, eth_dev);/* enable uio/vfio intr/eventfd mapping */rte_intr_enable(intr_handle);/* enable support intr */ixgbe_enable_intr(eth_dev);/* initialize filter info */memset(filter_info, 0,sizeof(struct ixgbe_filter_info));/* initialize 5tuple filter list */TAILQ_INIT(&filter_info->fivetuple_list);/* initialize flow director filter list & hash */ixgbe_fdir_filter_init(eth_dev);/* initialize l2 tunnel filter list & hash */ixgbe_l2_tn_filter_init(eth_dev);/* initialize flow filter lists */ixgbe_filterlist_init();/* initialize bandwidth configuration info */memset(bw_conf, 0, sizeof(struct ixgbe_bw_conf));/* initialize Traffic Manager configuration */ixgbe_tm_conf_init(eth_dev);return 0;
}

原文链接：https://www.cnblogs.com/codestack/p/15674071.html