text: /****************************************************************************
   * Driver for Solarflare Solarstorm network controllers and boards
   * Copyright 2005-2006 Fen Systems Ltd.
   * Copyright 2005-2011 Solarflare Communications Inc.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation, incorporated herein by reference.
   */
  
  /* Common definitions for all Efx net driver code */
  
  #ifndef EFX_NET_DRIVER_H
  #define EFX_NET_DRIVER_H
  
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/ethtool.h>
  #include <linux/if_vlan.h>
  #include <linux/timer.h>
  #include <linux/mdio.h>
  #include <linux/list.h>
  #include <linux/pci.h>
  #include <linux/device.h>
  #include <linux/highmem.h>
  #include <linux/workqueue.h>
  #include <linux/mutex.h>
  #include <linux/vmalloc.h>
  #include <linux/i2c.h>
  
  #include "enum.h"
  #include "bitfield.h"
  
  /**************************************************************************
   *
   * Build definitions
   *
   **************************************************************************/
  
  #define EFX_DRIVER_VERSION	"3.1"
  
  #ifdef DEBUG
  #define EFX_BUG_ON_PARANOID(x) BUG_ON(x)
  #define EFX_WARN_ON_PARANOID(x) WARN_ON(x)
  #else
  #define EFX_BUG_ON_PARANOID(x) do {} while (0)
  #define EFX_WARN_ON_PARANOID(x) do {} while (0)
  #endif
  
  /**************************************************************************
   *
   * Efx data structures
   *
   **************************************************************************/
  
  #define EFX_MAX_CHANNELS 32U
  #define EFX_MAX_RX_QUEUES EFX_MAX_CHANNELS
  #define EFX_EXTRA_CHANNEL_IOV	0
  #define EFX_MAX_EXTRA_CHANNELS	1U
  
  /* Checksum generation is a per-queue option in hardware, so each
   * queue visible to the networking core is backed by two hardware TX
   * queues. */
  #define EFX_MAX_TX_TC		2
  #define EFX_MAX_CORE_TX_QUEUES	(EFX_MAX_TX_TC * EFX_MAX_CHANNELS)
  #define EFX_TXQ_TYPE_OFFLOAD	1	/* flag */
  #define EFX_TXQ_TYPE_HIGHPRI	2	/* flag */
  #define EFX_TXQ_TYPES		4
  #define EFX_MAX_TX_QUEUES	(EFX_TXQ_TYPES * EFX_MAX_CHANNELS)
  
  struct efx_self_tests;
  
  /**
   * struct efx_special_buffer - An Efx special buffer
   * @addr: CPU base address of the buffer
   * @dma_addr: DMA base address of the buffer
   * @len: Buffer length, in bytes
   * @index: Buffer index within controller;s buffer table
   * @entries: Number of buffer table entries
   *
   * Special buffers are used for the event queues and the TX and RX
   * descriptor queues for each channel.  They are *not* used for the
   * actual transmit and receive buffers.
   */
  struct efx_special_buffer {
  	void *addr;
  	dma_addr_t dma_addr;
  	unsigned int len;
  	unsigned int index;
  	unsigned int entries;
  };
  
  /**
   * struct efx_tx_buffer - An Efx TX buffer
   * @skb: The associated socket buffer.
   *	Set only on the final fragment of a packet; %NULL for all other
   *	fragments.  When this fragment completes, then we can free this
   *	skb.
   * @tsoh: The associated TSO header structure, or %NULL if this
   *	buffer is not a TSO header.
   * @dma_addr: DMA address of the fragment.
   * @len: Length of this fragment.
   *	This field is zero when the queue slot is empty.
   * @continuation: True if this fragment is not the end of a packet.
   * @unmap_single: True if dma_unmap_single should be used.
   * @unmap_len: Length of this fragment to unmap
   */
  struct efx_tx_buffer {
  	const struct sk_buff *skb;
  	struct efx_tso_header *tsoh;
  	dma_addr_t dma_addr;
  	unsigned short len;
  	bool continuation;
  	bool unmap_single;
  	unsigned short unmap_len;
  };
  
  /**
   * struct efx_tx_queue - An Efx TX queue
   *
   * This is a ring buffer of TX fragments.
   * Since the TX completion path always executes on the same
   * CPU and the xmit path can operate on different CPUs,
   * performance is increased by ensuring that the completion
   * path and the xmit path operate on different cache lines.
   * This is particularly important if the xmit path is always
   * executing on one CPU which is different from the completion
   * path.  There is also a cache line for members which are
   * read but not written on the fast path.
   *
   * @efx: The associated Efx NIC
   * @queue: DMA queue number
   * @channel: The associated channel
   * @core_txq: The networking core TX queue structure
   * @buffer: The software buffer ring
   * @txd: The hardware descriptor ring
   * @ptr_mask: The size of the ring minus 1.
   * @initialised: Has hardware queue been initialised?
   * @read_count: Current read pointer.
   *	This is the number of buffers that have been removed from both rings.
   * @old_write_count: The value of @write_count when last checked.
   *	This is here for performance reasons.  The xmit path will
   *	only get the up-to-date value of @write_count if this
   *	variable indicates that the queue is empty.  This is to
   *	avoid cache-line ping-pong between the xmit path and the
   *	completion path.
   * @insert_count: Current insert pointer
   *	This is the number of buffers that have been added to the
   *	software ring.
   * @write_count: Current write pointer
   *	This is the number of buffers that have been added to the
   *	hardware ring.
   * @old_read_count: The value of read_count when last checked.
   *	This is here for performance reasons.  The xmit path will
   *	only get the up-to-date value of read_count if this
   *	variable indicates that the queue is full.  This is to
   *	avoid cache-line ping-pong between the xmit path and the
   *	completion path.
   * @tso_headers_free: A list of TSO headers allocated for this TX queue
   *	that are not in use, and so available for new TSO sends. The list
   *	is protected by the TX queue lock.
   * @tso_bursts: Number of times TSO xmit invoked by kernel
   * @tso_long_headers: Number of packets with headers too long for standard
   *	blocks
   * @tso_packets: Number of packets via the TSO xmit path
   * @pushes: Number of times the TX push feature has been used
   * @empty_read_count: If the completion path has seen the queue as empty
   *	and the transmission path has not yet checked this, the value of
   *	@read_count bitwise-added to %EFX_EMPTY_COUNT_VALID; otherwise 0.
   */
  struct efx_tx_queue {
  	/* Members which don't change on the fast path */
  	struct efx_nic *efx ____cacheline_aligned_in_smp;
  	unsigned queue;
  	struct efx_channel *channel;
  	struct netdev_queue *core_txq;
  	struct efx_tx_buffer *buffer;
  	struct efx_special_buffer txd;
  	unsigned int ptr_mask;
  	bool initialised;
  
  	/* Members used mainly on the completion path */
  	unsigned int read_count ____cacheline_aligned_in_smp;
  	unsigned int old_write_count;
  
  	/* Members used only on the xmit path */
  	unsigned int insert_count ____cacheline_aligned_in_smp;
  	unsigned int write_count;
  	unsigned int old_read_count;
  	struct efx_tso_header *tso_headers_free;
  	unsigned int tso_bursts;
  	unsigned int tso_long_headers;
  	unsigned int tso_packets;
  	unsigned int pushes;
  
  	/* Members shared between paths and sometimes updated */
  	unsigned int empty_read_count ____cacheline_aligned_in_smp;
  #define EFX_EMPTY_COUNT_VALID 0x80000000
  };
  
  /**
   * struct efx_rx_buffer - An Efx RX data buffer
   * @dma_addr: DMA base address of the buffer
   * @skb: The associated socket buffer. Valid iff !(@flags & %EFX_RX_BUF_PAGE).
   *	Will be %NULL if the buffer slot is currently free.
   * @page: The associated page buffer. Valif iff @flags & %EFX_RX_BUF_PAGE.
   *	Will be %NULL if the buffer slot is currently free.
   * @len: Buffer length, in bytes.
   * @flags: Flags for buffer and packet state.
   */
  struct efx_rx_buffer {
  	dma_addr_t dma_addr;
  	union {
  		struct sk_buff *skb;
  		struct page *page;
  	} u;
  	unsigned int len;
  	u16 flags;
  };
  #define EFX_RX_BUF_PAGE		0x0001
  #define EFX_RX_PKT_CSUMMED	0x0002
  #define EFX_RX_PKT_DISCARD	0x0004
  
  /**
   * struct efx_rx_page_state - Page-based rx buffer state
   *
   * Inserted at the start of every page allocated for receive buffers.
   * Used to facilitate sharing dma mappings between recycled rx buffers
   * and those passed up to the kernel.
   *
   * @refcnt: Number of struct efx_rx_buffer's referencing this page.
   *	When refcnt falls to zero, the page is unmapped for dma
   * @dma_addr: The dma address of this page.
   */
  struct efx_rx_page_state {
  	unsigned refcnt;
  	dma_addr_t dma_addr;
  
  	unsigned int __pad[0] ____cacheline_aligned;
  };
  
  /**
   * struct efx_rx_queue - An Efx RX queue
   * @efx: The associated Efx NIC
   * @buffer: The software buffer ring
   * @rxd: The hardware descriptor ring
   * @ptr_mask: The size of the ring minus 1.
   * @enabled: Receive queue enabled indicator.
   * @flush_pending: Set when a RX flush is pending. Has the same lifetime as
   *	@rxq_flush_pending.
   * @added_count: Number of buffers added to the receive queue.
   * @notified_count: Number of buffers given to NIC (<= @added_count).
   * @removed_count: Number of buffers removed from the receive queue.
   * @max_fill: RX descriptor maximum fill level (<= ring size)
   * @fast_fill_trigger: RX descriptor fill level that will trigger a fast fill
   *	(<= @max_fill)
   * @min_fill: RX descriptor minimum non-zero fill level.
   *	This records the minimum fill level observed when a ring
   *	refill was triggered.
   * @alloc_page_count: RX allocation strategy counter.
   * @alloc_skb_count: RX allocation strategy counter.
   * @slow_fill: Timer used to defer efx_nic_generate_fill_event().
   */
  struct efx_rx_queue {
  	struct efx_nic *efx;
  	struct efx_rx_buffer *buffer;
  	struct efx_special_buffer rxd;
  	unsigned int ptr_mask;
  	bool enabled;
  	bool flush_pending;
  
  	int added_count;
  	int notified_count;
  	int removed_count;
  	unsigned int max_fill;
  	unsigned int fast_fill_trigger;
  	unsigned int min_fill;
  	unsigned int min_overfill;
  	unsigned int alloc_page_count;
  	unsigned int alloc_skb_count;
  	struct timer_list slow_fill;
  	unsigned int slow_fill_count;
  };
  
  /**
   * struct efx_buffer - An Efx general-purpose buffer
   * @addr: host base address of the buffer
   * @dma_addr: DMA base address of the buffer
   * @len: Buffer length, in bytes
   *
   * The NIC uses these buffers for its interrupt status registers and
   * MAC stats dumps.
   */
  struct efx_buffer {
  	void *addr;
  	dma_addr_t dma_addr;
  	unsigned int len;
  };
  
  
  enum efx_rx_alloc_method {
  	RX_ALLOC_METHOD_AUTO = 0,
  	RX_ALLOC_METHOD_SKB = 1,
  	RX_ALLOC_METHOD_PAGE = 2,
  };
  
  /**
   * struct efx_channel - An Efx channel
   *
   * A channel comprises an event queue, at least one TX queue, at least
   * one RX queue, and an associated tasklet for processing the event
   * queue.
   *
   * @efx: Associated Efx NIC
   * @channel: Channel instance number
   * @type: Channel type definition
   * @enabled: Channel enabled indicator
   * @irq: IRQ number (MSI and MSI-X only)
   * @irq_moderation: IRQ moderation value (in hardware ticks)
   * @napi_dev: Net device used with NAPI
   * @napi_str: NAPI control structure
   * @work_pending: Is work pending via NAPI?
   * @eventq: Event queue buffer
   * @eventq_mask: Event queue pointer mask
   * @eventq_read_ptr: Event queue read pointer
   * @event_test_cpu: Last CPU to handle interrupt or test event for this channel
   * @irq_count: Number of IRQs since last adaptive moderation decision
   * @irq_mod_score: IRQ moderation score
   * @rx_alloc_level: Watermark based heuristic counter for pushing descriptors
   *	and diagnostic counters
   * @rx_alloc_push_pages: RX allocation method currently in use for pushing
   *	descriptors
   * @n_rx_tobe_disc: Count of RX_TOBE_DISC errors
   * @n_rx_ip_hdr_chksum_err: Count of RX IP header checksum errors
   * @n_rx_tcp_udp_chksum_err: Count of RX TCP and UDP checksum errors
   * @n_rx_mcast_mismatch: Count of unmatched multicast frames
   * @n_rx_frm_trunc: Count of RX_FRM_TRUNC errors
   * @n_rx_overlength: Count of RX_OVERLENGTH errors
   * @n_skbuff_leaks: Count of skbuffs leaked due to RX overrun
   * @rx_queue: RX queue for this channel
   * @tx_queue: TX queues for this channel
   */
  struct efx_channel {
  	struct efx_nic *efx;
  	int channel;
  	const struct efx_channel_type *type;
  	bool enabled;
  	int irq;
  	unsigned int irq_moderation;
  	struct net_device *napi_dev;
  	struct napi_struct napi_str;
  	bool work_pending;
  	struct efx_special_buffer eventq;
  	unsigned int eventq_mask;
  	unsigned int eventq_read_ptr;
  	int event_test_cpu;
  
  	unsigned int irq_count;
  	unsigned int irq_mod_score;
  #ifdef CONFIG_RFS_ACCEL
  	unsigned int rfs_filters_added;
  #endif
  
  	int rx_alloc_level;
  	int rx_alloc_push_pages;
  
  	unsigned n_rx_tobe_disc;
  	unsigned n_rx_ip_hdr_chksum_err;
  	unsigned n_rx_tcp_udp_chksum_err;
  	unsigned n_rx_mcast_mismatch;
  	unsigned n_rx_frm_trunc;
  	unsigned n_rx_overlength;
  	unsigned n_skbuff_leaks;
  
  	/* Used to pipeline received packets in order to optimise memory
  	 * access with prefetches.
  	 */
  	struct efx_rx_buffer *rx_pkt;
  
  	struct efx_rx_queue rx_queue;
  	struct efx_tx_queue tx_queue[EFX_TXQ_TYPES];
  };
  
  /**
   * struct efx_channel_type - distinguishes traffic and extra channels
   * @handle_no_channel: Handle failure to allocate an extra channel
   * @pre_probe: Set up extra state prior to initialisation
   * @post_remove: Tear down extra state after finalisation, if allocated.
   *	May be called on channels that have not been probed.
   * @get_name: Generate the channel's name (used for its IRQ handler)
   * @copy: Copy the channel state prior to reallocation.  May be %NULL if
   *	reallocation is not supported.
   * @keep_eventq: Flag for whether event queue should be kept initialised
   *	while the device is stopped
   */
  struct efx_channel_type {
  	void (*handle_no_channel)(struct efx_nic *);
  	int (*pre_probe)(struct efx_channel *);
  	void (*get_name)(struct efx_channel *, char *buf, size_t len);
  	struct efx_channel *(*copy)(const struct efx_channel *);
  	bool keep_eventq;
  };
  
  enum efx_led_mode {
  	EFX_LED_OFF	= 0,
  	EFX_LED_ON	= 1,
  	EFX_LED_DEFAULT	= 2
  };
  
  #define STRING_TABLE_LOOKUP(val, member) \
  	((val) < member ## _max) ? member ## _names[val] : "(invalid)"
  
  extern const char *const efx_loopback_mode_names[];
  extern const unsigned int efx_loopback_mode_max;
  #define LOOPBACK_MODE(efx) \
  	STRING_TABLE_LOOKUP((efx)->loopback_mode, efx_loopback_mode)
  
  extern const char *const efx_reset_type_names[];
  extern const unsigned int efx_reset_type_max;
  #define RESET_TYPE(type) \
  	STRING_TABLE_LOOKUP(type, efx_reset_type)
  
  enum efx_int_mode {
  	/* Be careful if altering to correct macro below */
  	EFX_INT_MODE_MSIX = 0,
  	EFX_INT_MODE_MSI = 1,
  	EFX_INT_MODE_LEGACY = 2,
  	EFX_INT_MODE_MAX	/* Insert any new items before this */
  };
  #define EFX_INT_MODE_USE_MSI(x) (((x)->interrupt_mode) <= EFX_INT_MODE_MSI)
  
  enum nic_state {
  	STATE_INIT = 0,
  	STATE_RUNNING = 1,
  	STATE_FINI = 2,
  	STATE_DISABLED = 3,
  	STATE_MAX,
  };
  
  /*
   * Alignment of page-allocated RX buffers
   *
   * Controls the number of bytes inserted at the start of an RX buffer.
   * This is the equivalent of NET_IP_ALIGN [which controls the alignment
   * of the skb->head for hardware DMA].
   */
  #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
  #define EFX_PAGE_IP_ALIGN 0
  #else
  #define EFX_PAGE_IP_ALIGN NET_IP_ALIGN
  #endif
  
  /*
   * Alignment of the skb->head which wraps a page-allocated RX buffer
   *
   * The skb allocated to wrap an rx_buffer can have this alignment. Since
   * the data is memcpy'd from the rx_buf, it does not need to be equal to
   * EFX_PAGE_IP_ALIGN.
   */
  #define EFX_PAGE_SKB_ALIGN 2
  
  /* Forward declaration */
  struct efx_nic;
  
  /* Pseudo bit-mask flow control field */
  #define EFX_FC_RX	FLOW_CTRL_RX
  #define EFX_FC_TX	FLOW_CTRL_TX
  #define EFX_FC_AUTO	4
  
  /**
   * struct efx_link_state - Current state of the link
   * @up: Link is up
   * @fd: Link is full-duplex
   * @fc: Actual flow control flags
   * @speed: Link speed (Mbps)
   */
  struct efx_link_state {
  	bool up;
  	bool fd;
  	u8 fc;
  	unsigned int speed;
  };
  
  static inline bool efx_link_state_equal(const struct efx_link_state *left,
  					const struct efx_link_state *right)
  {
  	return left->up == right->up && left->fd == right->fd &&
  		left->fc == right->fc && left->speed == right->speed;
  }
  
  /**
   * struct efx_phy_operations - Efx PHY operations table
   * @probe: Probe PHY and initialise efx->mdio.mode_support, efx->mdio.mmds,
   *	efx->loopback_modes.
   * @init: Initialise PHY
   * @fini: Shut down PHY
   * @reconfigure: Reconfigure PHY (e.g. for new link parameters)
   * @poll: Update @link_state and report whether it changed.
   *	Serialised by the mac_lock.
   * @get_settings: Get ethtool settings. Serialised by the mac_lock.
   * @set_settings: Set ethtool settings. Serialised by the mac_lock.
   * @set_npage_adv: Set abilities advertised in (Extended) Next Page
   *	(only needed where AN bit is set in mmds)
   * @test_alive: Test that PHY is 'alive' (online)
   * @test_name: Get the name of a PHY-specific test/result
   * @run_tests: Run tests and record results as appropriate (offline).
   *	Flags are the ethtool tests flags.
   */
  struct efx_phy_operations {
  	int (*probe) (struct efx_nic *efx);
  	int (*init) (struct efx_nic *efx);
  	void (*fini) (struct efx_nic *efx);
  	void (*remove) (struct efx_nic *efx);
  	int (*reconfigure) (struct efx_nic *efx);
  	bool (*poll) (struct efx_nic *efx);
  	void (*get_settings) (struct efx_nic *efx,
  			      struct ethtool_cmd *ecmd);
  	int (*set_settings) (struct efx_nic *efx,
  			     struct ethtool_cmd *ecmd);
  	void (*set_npage_adv) (struct efx_nic *efx, u32);
  	int (*test_alive) (struct efx_nic *efx);
  	const char *(*test_name) (struct efx_nic *efx, unsigned int index);
  	int (*run_tests) (struct efx_nic *efx, int *results, unsigned flags);
  	int (*get_module_eeprom) (struct efx_nic *efx,
  			       struct ethtool_eeprom *ee,
  			       u8 *data);
  	int (*get_module_info) (struct efx_nic *efx,
  				struct ethtool_modinfo *modinfo);
  };
  
  /**
   * enum efx_phy_mode - PHY operating mode flags
   * @PHY_MODE_NORMAL: on and should pass traffic
   * @PHY_MODE_TX_DISABLED: on with TX disabled
   * @PHY_MODE_LOW_POWER: set to low power through MDIO
   * @PHY_MODE_OFF: switched off through external control
   * @PHY_MODE_SPECIAL: on but will not pass traffic
   */
  enum efx_phy_mode {
  	PHY_MODE_NORMAL		= 0,
  	PHY_MODE_TX_DISABLED	= 1,
  	PHY_MODE_LOW_POWER	= 2,
  	PHY_MODE_OFF		= 4,
  	PHY_MODE_SPECIAL	= 8,
  };
  
  static inline bool efx_phy_mode_disabled(enum efx_phy_mode mode)
  {
  	return !!(mode & ~PHY_MODE_TX_DISABLED);
  }
  
  /*
   * Efx extended statistics
   *
   * Not all statistics are provided by all supported MACs.  The purpose
   * is this structure is to contain the raw statistics provided by each
   * MAC.
   */
  struct efx_mac_stats {
  	u64 tx_bytes;
  	u64 tx_good_bytes;
  	u64 tx_bad_bytes;
  	u64 tx_packets;
  	u64 tx_bad;
  	u64 tx_pause;
  	u64 tx_control;
  	u64 tx_unicast;
  	u64 tx_multicast;
  	u64 tx_broadcast;
  	u64 tx_lt64;
  	u64 tx_64;
  	u64 tx_65_to_127;
  	u64 tx_128_to_255;
  	u64 tx_256_to_511;
  	u64 tx_512_to_1023;
  	u64 tx_1024_to_15xx;
  	u64 tx_15xx_to_jumbo;
  	u64 tx_gtjumbo;
  	u64 tx_collision;
  	u64 tx_single_collision;
  	u64 tx_multiple_collision;
  	u64 tx_excessive_collision;
  	u64 tx_deferred;
  	u64 tx_late_collision;
  	u64 tx_excessive_deferred;
  	u64 tx_non_tcpudp;
  	u64 tx_mac_src_error;
  	u64 tx_ip_src_error;
  	u64 rx_bytes;
  	u64 rx_good_bytes;
  	u64 rx_bad_bytes;
  	u64 rx_packets;
  	u64 rx_good;
  	u64 rx_bad;
  	u64 rx_pause;
  	u64 rx_control;
  	u64 rx_unicast;
  	u64 rx_multicast;
  	u64 rx_broadcast;
  	u64 rx_lt64;
  	u64 rx_64;
  	u64 rx_65_to_127;
  	u64 rx_128_to_255;
  	u64 rx_256_to_511;
  	u64 rx_512_to_1023;
  	u64 rx_1024_to_15xx;
  	u64 rx_15xx_to_jumbo;
  	u64 rx_gtjumbo;
  	u64 rx_bad_lt64;
  	u64 rx_bad_64_to_15xx;
  	u64 rx_bad_15xx_to_jumbo;
  	u64 rx_bad_gtjumbo;
  	u64 rx_overflow;
  	u64 rx_missed;
  	u64 rx_false_carrier;
  	u64 rx_symbol_error;
  	u64 rx_align_error;
  	u64 rx_length_error;
  	u64 rx_internal_error;
  	u64 rx_good_lt64;
  };
  
  /* Number of bits used in a multicast filter hash address */
  #define EFX_MCAST_HASH_BITS 8
  
  /* Number of (single-bit) entries in a multicast filter hash */
  #define EFX_MCAST_HASH_ENTRIES (1 << EFX_MCAST_HASH_BITS)
  
  /* An Efx multicast filter hash */
  union efx_multicast_hash {
  	u8 byte[EFX_MCAST_HASH_ENTRIES / 8];
  	efx_oword_t oword[EFX_MCAST_HASH_ENTRIES / sizeof(efx_oword_t) / 8];
  };
  
  struct efx_filter_state;
  struct efx_vf;
  struct vfdi_status;
  
  /**
   * struct efx_nic - an Efx NIC
   * @name: Device name (net device name or bus id before net device registered)
   * @pci_dev: The PCI device
   * @type: Controller type attributes
   * @legacy_irq: IRQ number
   * @legacy_irq_enabled: Are IRQs enabled on NIC (INT_EN_KER register)?
   * @workqueue: Workqueue for port reconfigures and the HW monitor.
   *	Work items do not hold and must not acquire RTNL.
   * @workqueue_name: Name of workqueue
   * @reset_work: Scheduled reset workitem
   * @membase_phys: Memory BAR value as physical address
   * @membase: Memory BAR value
   * @interrupt_mode: Interrupt mode
   * @timer_quantum_ns: Interrupt timer quantum, in nanoseconds
   * @irq_rx_adaptive: Adaptive IRQ moderation enabled for RX event queues
   * @irq_rx_moderation: IRQ moderation time for RX event queues
   * @msg_enable: Log message enable flags
   * @state: Device state flag. Serialised by the rtnl_lock.
   * @reset_pending: Bitmask for pending resets
   * @tx_queue: TX DMA queues
   * @rx_queue: RX DMA queues
   * @channel: Channels
   * @channel_name: Names for channels and their IRQs
   * @extra_channel_types: Types of extra (non-traffic) channels that
   *	should be allocated for this NIC
   * @rxq_entries: Size of receive queues requested by user.
   * @txq_entries: Size of transmit queues requested by user.
   * @tx_dc_base: Base qword address in SRAM of TX queue descriptor caches
   * @rx_dc_base: Base qword address in SRAM of RX queue descriptor caches
   * @sram_lim_qw: Qword address limit of SRAM
   * @next_buffer_table: First available buffer table id
   * @n_channels: Number of channels in use
   * @n_rx_channels: Number of channels used for RX (= number of RX queues)
   * @n_tx_channels: Number of channels used for TX
   * @rx_buffer_len: RX buffer length
   * @rx_buffer_order: Order (log2) of number of pages for each RX buffer
   * @rx_hash_key: Toeplitz hash key for RSS
   * @rx_indir_table: Indirection table for RSS
   * @int_error_count: Number of internal errors seen recently
   * @int_error_expire: Time at which error count will be expired
   * @irq_status: Interrupt status buffer
   * @irq_zero_count: Number of legacy IRQs seen with queue flags == 0
   * @irq_level: IRQ level/index for IRQs not triggered by an event queue
   * @selftest_work: Work item for asynchronous self-test
   * @mtd_list: List of MTDs attached to the NIC
   * @nic_data: Hardware dependent state
   * @mac_lock: MAC access lock. Protects @port_enabled, @phy_mode,
   *	efx_monitor() and efx_reconfigure_port()
   * @port_enabled: Port enabled indicator.
   *	Serialises efx_stop_all(), efx_start_all(), efx_monitor() and
   *	efx_mac_work() with kernel interfaces. Safe to read under any
   *	one of the rtnl_lock, mac_lock, or netif_tx_lock, but all three must
   *	be held to modify it.
   * @port_initialized: Port initialized?
   * @net_dev: Operating system network device. Consider holding the rtnl lock
   * @stats_buffer: DMA buffer for statistics
   * @phy_type: PHY type
   * @phy_op: PHY interface
   * @phy_data: PHY private data (including PHY-specific stats)
   * @mdio: PHY MDIO interface
   * @mdio_bus: PHY MDIO bus ID (only used by Siena)
   * @phy_mode: PHY operating mode. Serialised by @mac_lock.
   * @link_advertising: Autonegotiation advertising flags
   * @link_state: Current state of the link
   * @n_link_state_changes: Number of times the link has changed state
   * @promiscuous: Promiscuous flag. Protected by netif_tx_lock.
   * @multicast_hash: Multicast hash table
   * @wanted_fc: Wanted flow control flags
   * @fc_disable: When non-zero flow control is disabled. Typically used to
   *	ensure that network back pressure doesn't delay dma queue flushes.
   *	Serialised by the rtnl lock.
   * @mac_work: Work item for changing MAC promiscuity and multicast hash
   * @loopback_mode: Loopback status
   * @loopback_modes: Supported loopback mode bitmask
   * @loopback_selftest: Offline self-test private state
   * @drain_pending: Count of RX and TX queues that haven't been flushed and drained.
   * @rxq_flush_pending: Count of number of receive queues that need to be flushed.
   *	Decremented when the efx_flush_rx_queue() is called.
   * @rxq_flush_outstanding: Count of number of RX flushes started but not yet
   *	completed (either success or failure). Not used when MCDI is used to
   *	flush receive queues.
   * @flush_wq: wait queue used by efx_nic_flush_queues() to wait for flush completions.
   * @vf: Array of &struct efx_vf objects.
   * @vf_count: Number of VFs intended to be enabled.
   * @vf_init_count: Number of VFs that have been fully initialised.
   * @vi_scale: log2 number of vnics per VF.
   * @vf_buftbl_base: The zeroth buffer table index used to back VF queues.
   * @vfdi_status: Common VFDI status page to be dmad to VF address space.
   * @local_addr_list: List of local addresses. Protected by %local_lock.
   * @local_page_list: List of DMA addressable pages used to broadcast
   *	%local_addr_list. Protected by %local_lock.
   * @local_lock: Mutex protecting %local_addr_list and %local_page_list.
   * @peer_work: Work item to broadcast peer addresses to VMs.
   * @monitor_work: Hardware monitor workitem
   * @biu_lock: BIU (bus interface unit) lock
   * @last_irq_cpu: Last CPU to handle a possible test interrupt.  This
   *	field is used by efx_test_interrupts() to verify that an
   *	interrupt has occurred.
   * @n_rx_nodesc_drop_cnt: RX no descriptor drop count
   * @mac_stats: MAC statistics. These include all statistics the MACs
   *	can provide.  Generic code converts these into a standard
   *	&struct net_device_stats.
   * @stats_lock: Statistics update lock. Serialises statistics fetches
   *	and access to @mac_stats.
   *
   * This is stored in the private area of the &struct net_device.
   */
  struct efx_nic {
  	/* The following fields should be written very rarely */
  
  	char name[IFNAMSIZ];
  	struct pci_dev *pci_dev;
  	const struct efx_nic_type *type;
  	int legacy_irq;
  	bool legacy_irq_enabled;
  	struct workqueue_struct *workqueue;
  	char workqueue_name[16];
  	struct work_struct reset_work;
  	resource_size_t membase_phys;
  	void __iomem *membase;
  
  	enum efx_int_mode interrupt_mode;
  	unsigned int timer_quantum_ns;
  	bool irq_rx_adaptive;
  	unsigned int irq_rx_moderation;
  	u32 msg_enable;
  
  	enum nic_state state;
  	unsigned long reset_pending;
  
  	struct efx_channel *channel[EFX_MAX_CHANNELS];
  	char channel_name[EFX_MAX_CHANNELS][IFNAMSIZ + 6];
  	const struct efx_channel_type *
  	extra_channel_type[EFX_MAX_EXTRA_CHANNELS];
  
  	unsigned rxq_entries;
  	unsigned txq_entries;
  	unsigned tx_dc_base;
  	unsigned rx_dc_base;
  	unsigned sram_lim_qw;
  	unsigned next_buffer_table;
  	unsigned n_channels;
  	unsigned n_rx_channels;
  	unsigned rss_spread;
  	unsigned tx_channel_offset;
  	unsigned n_tx_channels;
  	unsigned int rx_buffer_len;
  	unsigned int rx_buffer_order;
  	u8 rx_hash_key[40];
  	u32 rx_indir_table[128];
  
  	unsigned int_error_count;
  	unsigned long int_error_expire;
  
  	struct efx_buffer irq_status;
  	unsigned irq_zero_count;
  	unsigned irq_level;
  	struct delayed_work selftest_work;
  
  #ifdef CONFIG_SFC_MTD
  	struct list_head mtd_list;
  #endif
  
  	void *nic_data;
  
  	struct mutex mac_lock;
  	struct work_struct mac_work;
  	bool port_enabled;
  
  	bool port_initialized;
  	struct net_device *net_dev;
  
  	struct efx_buffer stats_buffer;
  
  	unsigned int phy_type;
  	const struct efx_phy_operations *phy_op;
  	void *phy_data;
  	struct mdio_if_info mdio;
  	unsigned int mdio_bus;
  	enum efx_phy_mode phy_mode;
  
  	u32 link_advertising;
  	struct efx_link_state link_state;
  	unsigned int n_link_state_changes;
  
  	bool promiscuous;
  	union efx_multicast_hash multicast_hash;
  	u8 wanted_fc;
  	unsigned fc_disable;
  
  	atomic_t rx_reset;
  	enum efx_loopback_mode loopback_mode;
  	u64 loopback_modes;
  
  	void *loopback_selftest;
  
  	struct efx_filter_state *filter_state;
  
  	atomic_t drain_pending;
  	atomic_t rxq_flush_pending;
  	atomic_t rxq_flush_outstanding;
  	wait_queue_head_t flush_wq;
  
  #ifdef CONFIG_SFC_SRIOV
  	struct efx_channel *vfdi_channel;
  	struct efx_vf *vf;
  	unsigned vf_count;
  	unsigned vf_init_count;
  	unsigned vi_scale;
  	unsigned vf_buftbl_base;
  	struct efx_buffer vfdi_status;
  	struct list_head local_addr_list;
  	struct list_head local_page_list;
  	struct mutex local_lock;
  	struct work_struct peer_work;
  #endif
  
  	/* The following fields may be written more often */
  
  	struct delayed_work monitor_work ____cacheline_aligned_in_smp;
  	spinlock_t biu_lock;
  	int last_irq_cpu;
  	unsigned n_rx_nodesc_drop_cnt;
  	struct efx_mac_stats mac_stats;
  	spinlock_t stats_lock;
  };
  
  static inline int efx_dev_registered(struct efx_nic *efx)
  {
  	return efx->net_dev->reg_state == NETREG_REGISTERED;
  }
  
  static inline unsigned int efx_port_num(struct efx_nic *efx)
  {
  	return efx->net_dev->dev_id;
  }
  
  /**
   * struct efx_nic_type - Efx device type definition
   * @probe: Probe the controller
   * @remove: Free resources allocated by probe()
   * @init: Initialise the controller
   * @dimension_resources: Dimension controller resources (buffer table,
   *	and VIs once the available interrupt resources are clear)
   * @fini: Shut down the controller
   * @monitor: Periodic function for polling link state and hardware monitor
   * @map_reset_reason: Map ethtool reset reason to a reset method
   * @map_reset_flags: Map ethtool reset flags to a reset method, if possible
   * @reset: Reset the controller hardware and possibly the PHY.  This will
   *	be called while the controller is uninitialised.
   * @probe_port: Probe the MAC and PHY
   * @remove_port: Free resources allocated by probe_port()
   * @handle_global_event: Handle a "global" event (may be %NULL)
   * @prepare_flush: Prepare the hardware for flushing the DMA queues
   * @update_stats: Update statistics not provided by event handling
   * @start_stats: Start the regular fetching of statistics
   * @stop_stats: Stop the regular fetching of statistics
   * @set_id_led: Set state of identifying LED or revert to automatic function
   * @push_irq_moderation: Apply interrupt moderation value
   * @reconfigure_port: Push loopback/power/txdis changes to the MAC and PHY
   * @reconfigure_mac: Push MAC address, MTU, flow control and filter settings
   *	to the hardware.  Serialised by the mac_lock.
   * @check_mac_fault: Check MAC fault state. True if fault present.
   * @get_wol: Get WoL configuration from driver state
   * @set_wol: Push WoL configuration to the NIC
   * @resume_wol: Synchronise WoL state between driver and MC (e.g. after resume)
   * @test_chip: Test registers.  Should use efx_nic_test_registers(), and is
   *	expected to reset the NIC.
   * @test_nvram: Test validity of NVRAM contents
   * @revision: Hardware architecture revision
   * @mem_map_size: Memory BAR mapped size
   * @txd_ptr_tbl_base: TX descriptor ring base address
   * @rxd_ptr_tbl_base: RX descriptor ring base address
   * @buf_tbl_base: Buffer table base address
   * @evq_ptr_tbl_base: Event queue pointer table base address
   * @evq_rptr_tbl_base: Event queue read-pointer table base address
   * @max_dma_mask: Maximum possible DMA mask
   * @rx_buffer_hash_size: Size of hash at start of RX buffer
   * @rx_buffer_padding: Size of padding at end of RX buffer
   * @max_interrupt_mode: Highest capability interrupt mode supported
   *	from &enum efx_init_mode.
   * @phys_addr_channels: Number of channels with physically addressed
   *	descriptors
   * @timer_period_max: Maximum period of interrupt timer (in ticks)
   * @offload_features: net_device feature flags for protocol offload
   *	features implemented in hardware
   */
  struct efx_nic_type {
  	int (*probe)(struct efx_nic *efx);
  	void (*remove)(struct efx_nic *efx);
  	int (*init)(struct efx_nic *efx);
  	void (*dimension_resources)(struct efx_nic *efx);
  	void (*fini)(struct efx_nic *efx);
  	void (*monitor)(struct efx_nic *efx);
  	enum reset_type (*map_reset_reason)(enum reset_type reason);
  	int (*map_reset_flags)(u32 *flags);
  	int (*reset)(struct efx_nic *efx, enum reset_type method);
  	int (*probe_port)(struct efx_nic *efx);
  	void (*remove_port)(struct efx_nic *efx);
  	bool (*handle_global_event)(struct efx_channel *channel, efx_qword_t *);
  	void (*prepare_flush)(struct efx_nic *efx);
  	void (*update_stats)(struct efx_nic *efx);
  	void (*start_stats)(struct efx_nic *efx);
  	void (*stop_stats)(struct efx_nic *efx);
  	void (*set_id_led)(struct efx_nic *efx, enum efx_led_mode mode);
  	void (*push_irq_moderation)(struct efx_channel *channel);
  	int (*reconfigure_port)(struct efx_nic *efx);
  	int (*reconfigure_mac)(struct efx_nic *efx);
  	bool (*check_mac_fault)(struct efx_nic *efx);
  	void (*get_wol)(struct efx_nic *efx, struct ethtool_wolinfo *wol);
  	int (*set_wol)(struct efx_nic *efx, u32 type);
  	void (*resume_wol)(struct efx_nic *efx);
  	int (*test_chip)(struct efx_nic *efx, struct efx_self_tests *tests);
  	int (*test_nvram)(struct efx_nic *efx);
  
  	int revision;
  	unsigned int mem_map_size;
  	unsigned int txd_ptr_tbl_base;
  	unsigned int rxd_ptr_tbl_base;
  	unsigned int buf_tbl_base;
  	unsigned int evq_ptr_tbl_base;
  	unsigned int evq_rptr_tbl_base;
  	u64 max_dma_mask;
  	unsigned int rx_buffer_hash_size;
  	unsigned int rx_buffer_padding;
  	unsigned int max_interrupt_mode;
  	unsigned int phys_addr_channels;
  	unsigned int timer_period_max;
  	netdev_features_t offload_features;
  };
  
  /**************************************************************************
   *
   * Prototypes and inline functions
   *
   *************************************************************************/
  
  static inline struct efx_channel *
  efx_get_channel(struct efx_nic *efx, unsigned index)
  {
  	EFX_BUG_ON_PARANOID(index >= efx->n_channels);
  	return efx->channel[index];
  }
  
  /* Iterate over all used channels */
  #define efx_for_each_channel(_channel, _efx)				\
  	for (_channel = (_efx)->channel[0];				\
  	     _channel;							\
  	     _channel = (_channel->channel + 1 < (_efx)->n_channels) ?	\
  		     (_efx)->channel[_channel->channel + 1] : NULL)
  
  /* Iterate over all used channels in reverse */
  #define efx_for_each_channel_rev(_channel, _efx)			\
  	for (_channel = (_efx)->channel[(_efx)->n_channels - 1];	\
  	     _channel;							\
  	     _channel = _channel->channel ?				\
  		     (_efx)->channel[_channel->channel - 1] : NULL)
  
  static inline struct efx_tx_queue *
  efx_get_tx_queue(struct efx_nic *efx, unsigned index, unsigned type)
  {
  	EFX_BUG_ON_PARANOID(index >= efx->n_tx_channels ||
  			    type >= EFX_TXQ_TYPES);
  	return &efx->channel[efx->tx_channel_offset + index]->tx_queue[type];
  }
  
  static inline bool efx_channel_has_tx_queues(struct efx_channel *channel)
  {
  	return channel->channel - channel->efx->tx_channel_offset <
  		channel->efx->n_tx_channels;
  }
  
  static inline struct efx_tx_queue *
  efx_channel_get_tx_queue(struct efx_channel *channel, unsigned type)
  {
  	EFX_BUG_ON_PARANOID(!efx_channel_has_tx_queues(channel) ||
  			    type >= EFX_TXQ_TYPES);
  	return &channel->tx_queue[type];
  }
  
  static inline bool efx_tx_queue_used(struct efx_tx_queue *tx_queue)
  {
  	return !(tx_queue->efx->net_dev->num_tc < 2 &&
  		 tx_queue->queue & EFX_TXQ_TYPE_HIGHPRI);
  }
  
  /* Iterate over all TX queues belonging to a channel */
  #define efx_for_each_channel_tx_queue(_tx_queue, _channel)		\
  	if (!efx_channel_has_tx_queues(_channel))			\
  		;							\
  	else								\
  		for (_tx_queue = (_channel)->tx_queue;			\
  		     _tx_queue < (_channel)->tx_queue + EFX_TXQ_TYPES && \
  			     efx_tx_queue_used(_tx_queue);		\
  		     _tx_queue++)
  
  /* Iterate over all possible TX queues belonging to a channel */
  #define efx_for_each_possible_channel_tx_queue(_tx_queue, _channel)	\
  	if (!efx_channel_has_tx_queues(_channel))			\
  		;							\
  	else								\
  		for (_tx_queue = (_channel)->tx_queue;			\
  		     _tx_queue < (_channel)->tx_queue + EFX_TXQ_TYPES;	\
  		     _tx_queue++)
  
  static inline bool efx_channel_has_rx_queue(struct efx_channel *channel)
  {
  	return channel->channel < channel->efx->n_rx_channels;
  }
  
  static inline struct efx_rx_queue *
  efx_channel_get_rx_queue(struct efx_channel *channel)
  {
  	EFX_BUG_ON_PARANOID(!efx_channel_has_rx_queue(channel));
  	return &channel->rx_queue;
  }
  
  /* Iterate over all RX queues belonging to a channel */
  #define efx_for_each_channel_rx_queue(_rx_queue, _channel)		\
  	if (!efx_channel_has_rx_queue(_channel))			\
  		;							\
  	else								\
  		for (_rx_queue = &(_channel)->rx_queue;			\
  		     _rx_queue;						\
  		     _rx_queue = NULL)
  
  static inline struct efx_channel *
  efx_rx_queue_channel(struct efx_rx_queue *rx_queue)
  {
  	return container_of(rx_queue, struct efx_channel, rx_queue);
  }
  
  static inline int efx_rx_queue_index(struct efx_rx_queue *rx_queue)
  {
  	return efx_rx_queue_channel(rx_queue)->channel;
  }
  
  /* Returns a pointer to the specified receive buffer in the RX
   * descriptor queue.
   */
  static inline struct efx_rx_buffer *efx_rx_buffer(struct efx_rx_queue *rx_queue,
  						  unsigned int index)
  {
  	return &rx_queue->buffer[index];
  }
  
  /* Set bit in a little-endian bitfield */
  static inline void set_bit_le(unsigned nr, unsigned char *addr)
  {
  	addr[nr / 8] |= (1 << (nr % 8));
  }
  
  /* Clear bit in a little-endian bitfield */
  static inline void clear_bit_le(unsigned nr, unsigned char *addr)
  {
  	addr[nr / 8] &= ~(1 << (nr % 8));
  }
  
  
  /**
   * EFX_MAX_FRAME_LEN - calculate maximum frame length
   *
   * This calculates the maximum frame length that will be used for a
   * given MTU.  The frame length will be equal to the MTU plus a
   * constant amount of header space and padding.  This is the quantity
   * that the net driver will program into the MAC as the maximum frame
   * length.
   *
   * The 10G MAC requires 8-byte alignment on the frame
   * length, so we round up to the nearest 8.
   *
   * Re-clocking by the XGXS on RX can reduce an IPG to 32 bits (half an
   * XGMII cycle).  If the frame length reaches the maximum value in the
   * same cycle, the XMAC can miss the IPG altogether.  We work around
   * this by adding a further 16 bytes.
   */
  #define EFX_MAX_FRAME_LEN(mtu) \
  	((((mtu) + ETH_HLEN + VLAN_HLEN + 4/* FCS */ + 7) & ~7) + 16)
  
  
  #endif /* EFX_NET_DRIVER_H */
  