1 /****************************************************************************
2  * Driver for Solarflare Solarstorm network controllers and boards
3  * Copyright 2005-2006 Fen Systems Ltd.
4  * Copyright 2005-2011 Solarflare Communications Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published
8  * by the Free Software Foundation, incorporated herein by reference.
9  */
10 
11 /* Common definitions for all Efx net driver code */
12 
13 #ifndef EFX_NET_DRIVER_H
14 #define EFX_NET_DRIVER_H
15 
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/ethtool.h>
19 #include <linux/if_vlan.h>
20 #include <linux/timer.h>
21 #include <linux/mdio.h>
22 #include <linux/list.h>
23 #include <linux/pci.h>
24 #include <linux/device.h>
25 #include <linux/highmem.h>
26 #include <linux/workqueue.h>
27 #include <linux/mutex.h>
28 #include <linux/vmalloc.h>
29 #include <linux/i2c.h>
30 
31 #include "enum.h"
32 #include "bitfield.h"
33 
34 /**************************************************************************
35  *
36  * Build definitions
37  *
38  **************************************************************************/
39 
40 #define EFX_DRIVER_VERSION	"3.2"
41 
42 #ifdef DEBUG
43 #define EFX_BUG_ON_PARANOID(x) BUG_ON(x)
44 #define EFX_WARN_ON_PARANOID(x) WARN_ON(x)
45 #else
46 #define EFX_BUG_ON_PARANOID(x) do {} while (0)
47 #define EFX_WARN_ON_PARANOID(x) do {} while (0)
48 #endif
49 
50 /**************************************************************************
51  *
52  * Efx data structures
53  *
54  **************************************************************************/
55 
56 #define EFX_MAX_CHANNELS 32U
57 #define EFX_MAX_RX_QUEUES EFX_MAX_CHANNELS
58 #define EFX_EXTRA_CHANNEL_IOV	0
59 #define EFX_EXTRA_CHANNEL_PTP	1
60 #define EFX_MAX_EXTRA_CHANNELS	2U
61 
62 /* Checksum generation is a per-queue option in hardware, so each
63  * queue visible to the networking core is backed by two hardware TX
64  * queues. */
65 #define EFX_MAX_TX_TC		2
66 #define EFX_MAX_CORE_TX_QUEUES	(EFX_MAX_TX_TC * EFX_MAX_CHANNELS)
67 #define EFX_TXQ_TYPE_OFFLOAD	1	/* flag */
68 #define EFX_TXQ_TYPE_HIGHPRI	2	/* flag */
69 #define EFX_TXQ_TYPES		4
70 #define EFX_MAX_TX_QUEUES	(EFX_TXQ_TYPES * EFX_MAX_CHANNELS)
71 
72 /* Maximum possible MTU the driver supports */
73 #define EFX_MAX_MTU (9 * 1024)
74 
75 /* Size of an RX scatter buffer.  Small enough to pack 2 into a 4K page,
76  * and should be a multiple of the cache line size.
77  */
78 #define EFX_RX_USR_BUF_SIZE	(2048 - 256)
79 
80 /* If possible, we should ensure cache line alignment at start and end
81  * of every buffer.  Otherwise, we just need to ensure 4-byte
82  * alignment of the network header.
83  */
84 #if NET_IP_ALIGN == 0
85 #define EFX_RX_BUF_ALIGNMENT	L1_CACHE_BYTES
86 #else
87 #define EFX_RX_BUF_ALIGNMENT	4
88 #endif
89 
90 /* Forward declare Precision Time Protocol (PTP) support structure. */
91 struct efx_ptp_data;
92 
93 struct efx_self_tests;
94 
95 /**
96  * struct efx_special_buffer - An Efx special buffer
97  * @addr: CPU base address of the buffer
98  * @dma_addr: DMA base address of the buffer
99  * @len: Buffer length, in bytes
100  * @index: Buffer index within controller;s buffer table
101  * @entries: Number of buffer table entries
102  *
103  * Special buffers are used for the event queues and the TX and RX
104  * descriptor queues for each channel.  They are *not* used for the
105  * actual transmit and receive buffers.
106  */
107 struct efx_special_buffer {
108 	void *addr;
109 	dma_addr_t dma_addr;
110 	unsigned int len;
111 	unsigned int index;
112 	unsigned int entries;
113 };
114 
115 /**
116  * struct efx_tx_buffer - buffer state for a TX descriptor
117  * @skb: When @flags & %EFX_TX_BUF_SKB, the associated socket buffer to be
118  *	freed when descriptor completes
119  * @heap_buf: When @flags & %EFX_TX_BUF_HEAP, the associated heap buffer to be
120  *	freed when descriptor completes.
121  * @dma_addr: DMA address of the fragment.
122  * @flags: Flags for allocation and DMA mapping type
123  * @len: Length of this fragment.
124  *	This field is zero when the queue slot is empty.
125  * @unmap_len: Length of this fragment to unmap
126  */
127 struct efx_tx_buffer {
128 	union {
129 		const struct sk_buff *skb;
130 		void *heap_buf;
131 	};
132 	dma_addr_t dma_addr;
133 	unsigned short flags;
134 	unsigned short len;
135 	unsigned short unmap_len;
136 };
137 #define EFX_TX_BUF_CONT		1	/* not last descriptor of packet */
138 #define EFX_TX_BUF_SKB		2	/* buffer is last part of skb */
139 #define EFX_TX_BUF_HEAP		4	/* buffer was allocated with kmalloc() */
140 #define EFX_TX_BUF_MAP_SINGLE	8	/* buffer was mapped with dma_map_single() */
141 
142 /**
143  * struct efx_tx_queue - An Efx TX queue
144  *
145  * This is a ring buffer of TX fragments.
146  * Since the TX completion path always executes on the same
147  * CPU and the xmit path can operate on different CPUs,
148  * performance is increased by ensuring that the completion
149  * path and the xmit path operate on different cache lines.
150  * This is particularly important if the xmit path is always
151  * executing on one CPU which is different from the completion
152  * path.  There is also a cache line for members which are
153  * read but not written on the fast path.
154  *
155  * @efx: The associated Efx NIC
156  * @queue: DMA queue number
157  * @channel: The associated channel
158  * @core_txq: The networking core TX queue structure
159  * @buffer: The software buffer ring
160  * @tsoh_page: Array of pages of TSO header buffers
161  * @txd: The hardware descriptor ring
162  * @ptr_mask: The size of the ring minus 1.
163  * @initialised: Has hardware queue been initialised?
164  * @read_count: Current read pointer.
165  *	This is the number of buffers that have been removed from both rings.
166  * @old_write_count: The value of @write_count when last checked.
167  *	This is here for performance reasons.  The xmit path will
168  *	only get the up-to-date value of @write_count if this
169  *	variable indicates that the queue is empty.  This is to
170  *	avoid cache-line ping-pong between the xmit path and the
171  *	completion path.
172  * @insert_count: Current insert pointer
173  *	This is the number of buffers that have been added to the
174  *	software ring.
175  * @write_count: Current write pointer
176  *	This is the number of buffers that have been added to the
177  *	hardware ring.
178  * @old_read_count: The value of read_count when last checked.
179  *	This is here for performance reasons.  The xmit path will
180  *	only get the up-to-date value of read_count if this
181  *	variable indicates that the queue is full.  This is to
182  *	avoid cache-line ping-pong between the xmit path and the
183  *	completion path.
184  * @tso_bursts: Number of times TSO xmit invoked by kernel
185  * @tso_long_headers: Number of packets with headers too long for standard
186  *	blocks
187  * @tso_packets: Number of packets via the TSO xmit path
188  * @pushes: Number of times the TX push feature has been used
189  * @empty_read_count: If the completion path has seen the queue as empty
190  *	and the transmission path has not yet checked this, the value of
191  *	@read_count bitwise-added to %EFX_EMPTY_COUNT_VALID; otherwise 0.
192  */
193 struct efx_tx_queue {
194 	/* Members which don't change on the fast path */
195 	struct efx_nic *efx ____cacheline_aligned_in_smp;
196 	unsigned queue;
197 	struct efx_channel *channel;
198 	struct netdev_queue *core_txq;
199 	struct efx_tx_buffer *buffer;
200 	struct efx_buffer *tsoh_page;
201 	struct efx_special_buffer txd;
202 	unsigned int ptr_mask;
203 	bool initialised;
204 
205 	/* Members used mainly on the completion path */
206 	unsigned int read_count ____cacheline_aligned_in_smp;
207 	unsigned int old_write_count;
208 
209 	/* Members used only on the xmit path */
210 	unsigned int insert_count ____cacheline_aligned_in_smp;
211 	unsigned int write_count;
212 	unsigned int old_read_count;
213 	unsigned int tso_bursts;
214 	unsigned int tso_long_headers;
215 	unsigned int tso_packets;
216 	unsigned int pushes;
217 
218 	/* Members shared between paths and sometimes updated */
219 	unsigned int empty_read_count ____cacheline_aligned_in_smp;
220 #define EFX_EMPTY_COUNT_VALID 0x80000000
221 	atomic_t flush_outstanding;
222 };
223 
224 /**
225  * struct efx_rx_buffer - An Efx RX data buffer
226  * @dma_addr: DMA base address of the buffer
227  * @page: The associated page buffer.
228  *	Will be %NULL if the buffer slot is currently free.
229  * @page_offset: If pending: offset in @page of DMA base address.
230  *	If completed: offset in @page of Ethernet header.
231  * @len: If pending: length for DMA descriptor.
232  *	If completed: received length, excluding hash prefix.
233  * @flags: Flags for buffer and packet state.  These are only set on the
234  *	first buffer of a scattered packet.
235  */
236 struct efx_rx_buffer {
237 	dma_addr_t dma_addr;
238 	struct page *page;
239 	u16 page_offset;
240 	u16 len;
241 	u16 flags;
242 };
243 #define EFX_RX_BUF_LAST_IN_PAGE	0x0001
244 #define EFX_RX_PKT_CSUMMED	0x0002
245 #define EFX_RX_PKT_DISCARD	0x0004
246 
247 /**
248  * struct efx_rx_page_state - Page-based rx buffer state
249  *
250  * Inserted at the start of every page allocated for receive buffers.
251  * Used to facilitate sharing dma mappings between recycled rx buffers
252  * and those passed up to the kernel.
253  *
254  * @refcnt: Number of struct efx_rx_buffer's referencing this page.
255  *	When refcnt falls to zero, the page is unmapped for dma
256  * @dma_addr: The dma address of this page.
257  */
258 struct efx_rx_page_state {
259 	unsigned refcnt;
260 	dma_addr_t dma_addr;
261 
262 	unsigned int __pad[0] ____cacheline_aligned;
263 };
264 
265 /**
266  * struct efx_rx_queue - An Efx RX queue
267  * @efx: The associated Efx NIC
268  * @core_index:  Index of network core RX queue.  Will be >= 0 iff this
269  *	is associated with a real RX queue.
270  * @buffer: The software buffer ring
271  * @rxd: The hardware descriptor ring
272  * @ptr_mask: The size of the ring minus 1.
273  * @enabled: Receive queue enabled indicator.
274  * @flush_pending: Set when a RX flush is pending. Has the same lifetime as
275  *	@rxq_flush_pending.
276  * @added_count: Number of buffers added to the receive queue.
277  * @notified_count: Number of buffers given to NIC (<= @added_count).
278  * @removed_count: Number of buffers removed from the receive queue.
279  * @scatter_n: Number of buffers used by current packet
280  * @page_ring: The ring to store DMA mapped pages for reuse.
281  * @page_add: Counter to calculate the write pointer for the recycle ring.
282  * @page_remove: Counter to calculate the read pointer for the recycle ring.
283  * @page_recycle_count: The number of pages that have been recycled.
284  * @page_recycle_failed: The number of pages that couldn't be recycled because
285  *      the kernel still held a reference to them.
286  * @page_recycle_full: The number of pages that were released because the
287  *      recycle ring was full.
288  * @page_ptr_mask: The number of pages in the RX recycle ring minus 1.
289  * @max_fill: RX descriptor maximum fill level (<= ring size)
290  * @fast_fill_trigger: RX descriptor fill level that will trigger a fast fill
291  *	(<= @max_fill)
292  * @min_fill: RX descriptor minimum non-zero fill level.
293  *	This records the minimum fill level observed when a ring
294  *	refill was triggered.
295  * @recycle_count: RX buffer recycle counter.
296  * @slow_fill: Timer used to defer efx_nic_generate_fill_event().
297  */
298 struct efx_rx_queue {
299 	struct efx_nic *efx;
300 	int core_index;
301 	struct efx_rx_buffer *buffer;
302 	struct efx_special_buffer rxd;
303 	unsigned int ptr_mask;
304 	bool enabled;
305 	bool flush_pending;
306 
307 	unsigned int added_count;
308 	unsigned int notified_count;
309 	unsigned int removed_count;
310 	unsigned int scatter_n;
311 	struct page **page_ring;
312 	unsigned int page_add;
313 	unsigned int page_remove;
314 	unsigned int page_recycle_count;
315 	unsigned int page_recycle_failed;
316 	unsigned int page_recycle_full;
317 	unsigned int page_ptr_mask;
318 	unsigned int max_fill;
319 	unsigned int fast_fill_trigger;
320 	unsigned int min_fill;
321 	unsigned int min_overfill;
322 	unsigned int recycle_count;
323 	struct timer_list slow_fill;
324 	unsigned int slow_fill_count;
325 };
326 
327 /**
328  * struct efx_buffer - An Efx general-purpose buffer
329  * @addr: host base address of the buffer
330  * @dma_addr: DMA base address of the buffer
331  * @len: Buffer length, in bytes
332  *
333  * The NIC uses these buffers for its interrupt status registers and
334  * MAC stats dumps.
335  */
336 struct efx_buffer {
337 	void *addr;
338 	dma_addr_t dma_addr;
339 	unsigned int len;
340 };
341 
342 
343 enum efx_rx_alloc_method {
344 	RX_ALLOC_METHOD_AUTO = 0,
345 	RX_ALLOC_METHOD_SKB = 1,
346 	RX_ALLOC_METHOD_PAGE = 2,
347 };
348 
349 /**
350  * struct efx_channel - An Efx channel
351  *
352  * A channel comprises an event queue, at least one TX queue, at least
353  * one RX queue, and an associated tasklet for processing the event
354  * queue.
355  *
356  * @efx: Associated Efx NIC
357  * @channel: Channel instance number
358  * @type: Channel type definition
359  * @enabled: Channel enabled indicator
360  * @irq: IRQ number (MSI and MSI-X only)
361  * @irq_moderation: IRQ moderation value (in hardware ticks)
362  * @napi_dev: Net device used with NAPI
363  * @napi_str: NAPI control structure
364  * @work_pending: Is work pending via NAPI?
365  * @eventq: Event queue buffer
366  * @eventq_mask: Event queue pointer mask
367  * @eventq_read_ptr: Event queue read pointer
368  * @event_test_cpu: Last CPU to handle interrupt or test event for this channel
369  * @irq_count: Number of IRQs since last adaptive moderation decision
370  * @irq_mod_score: IRQ moderation score
371  * @n_rx_tobe_disc: Count of RX_TOBE_DISC errors
372  * @n_rx_ip_hdr_chksum_err: Count of RX IP header checksum errors
373  * @n_rx_tcp_udp_chksum_err: Count of RX TCP and UDP checksum errors
374  * @n_rx_mcast_mismatch: Count of unmatched multicast frames
375  * @n_rx_frm_trunc: Count of RX_FRM_TRUNC errors
376  * @n_rx_overlength: Count of RX_OVERLENGTH errors
377  * @n_skbuff_leaks: Count of skbuffs leaked due to RX overrun
378  * @n_rx_nodesc_trunc: Number of RX packets truncated and then dropped due to
379  *	lack of descriptors
380  * @rx_pkt_n_frags: Number of fragments in next packet to be delivered by
381  *	__efx_rx_packet(), or zero if there is none
382  * @rx_pkt_index: Ring index of first buffer for next packet to be delivered
383  *	by __efx_rx_packet(), if @rx_pkt_n_frags != 0
384  * @rx_queue: RX queue for this channel
385  * @tx_queue: TX queues for this channel
386  */
387 struct efx_channel {
388 	struct efx_nic *efx;
389 	int channel;
390 	const struct efx_channel_type *type;
391 	bool enabled;
392 	int irq;
393 	unsigned int irq_moderation;
394 	struct net_device *napi_dev;
395 	struct napi_struct napi_str;
396 	bool work_pending;
397 	struct efx_special_buffer eventq;
398 	unsigned int eventq_mask;
399 	unsigned int eventq_read_ptr;
400 	int event_test_cpu;
401 
402 	unsigned int irq_count;
403 	unsigned int irq_mod_score;
404 #ifdef CONFIG_RFS_ACCEL
405 	unsigned int rfs_filters_added;
406 #endif
407 
408 	unsigned n_rx_tobe_disc;
409 	unsigned n_rx_ip_hdr_chksum_err;
410 	unsigned n_rx_tcp_udp_chksum_err;
411 	unsigned n_rx_mcast_mismatch;
412 	unsigned n_rx_frm_trunc;
413 	unsigned n_rx_overlength;
414 	unsigned n_skbuff_leaks;
415 	unsigned int n_rx_nodesc_trunc;
416 
417 	unsigned int rx_pkt_n_frags;
418 	unsigned int rx_pkt_index;
419 
420 	struct efx_rx_queue rx_queue;
421 	struct efx_tx_queue tx_queue[EFX_TXQ_TYPES];
422 };
423 
424 /**
425  * struct efx_channel_type - distinguishes traffic and extra channels
426  * @handle_no_channel: Handle failure to allocate an extra channel
427  * @pre_probe: Set up extra state prior to initialisation
428  * @post_remove: Tear down extra state after finalisation, if allocated.
429  *	May be called on channels that have not been probed.
430  * @get_name: Generate the channel's name (used for its IRQ handler)
431  * @copy: Copy the channel state prior to reallocation.  May be %NULL if
432  *	reallocation is not supported.
433  * @receive_skb: Handle an skb ready to be passed to netif_receive_skb()
434  * @keep_eventq: Flag for whether event queue should be kept initialised
435  *	while the device is stopped
436  */
437 struct efx_channel_type {
438 	void (*handle_no_channel)(struct efx_nic *);
439 	int (*pre_probe)(struct efx_channel *);
440 	void (*post_remove)(struct efx_channel *);
441 	void (*get_name)(struct efx_channel *, char *buf, size_t len);
442 	struct efx_channel *(*copy)(const struct efx_channel *);
443 	bool (*receive_skb)(struct efx_channel *, struct sk_buff *);
444 	bool keep_eventq;
445 };
446 
447 enum efx_led_mode {
448 	EFX_LED_OFF	= 0,
449 	EFX_LED_ON	= 1,
450 	EFX_LED_DEFAULT	= 2
451 };
452 
453 #define STRING_TABLE_LOOKUP(val, member) \
454 	((val) < member ## _max) ? member ## _names[val] : "(invalid)"
455 
456 extern const char *const efx_loopback_mode_names[];
457 extern const unsigned int efx_loopback_mode_max;
458 #define LOOPBACK_MODE(efx) \
459 	STRING_TABLE_LOOKUP((efx)->loopback_mode, efx_loopback_mode)
460 
461 extern const char *const efx_reset_type_names[];
462 extern const unsigned int efx_reset_type_max;
463 #define RESET_TYPE(type) \
464 	STRING_TABLE_LOOKUP(type, efx_reset_type)
465 
466 enum efx_int_mode {
467 	/* Be careful if altering to correct macro below */
468 	EFX_INT_MODE_MSIX = 0,
469 	EFX_INT_MODE_MSI = 1,
470 	EFX_INT_MODE_LEGACY = 2,
471 	EFX_INT_MODE_MAX	/* Insert any new items before this */
472 };
473 #define EFX_INT_MODE_USE_MSI(x) (((x)->interrupt_mode) <= EFX_INT_MODE_MSI)
474 
475 enum nic_state {
476 	STATE_UNINIT = 0,	/* device being probed/removed or is frozen */
477 	STATE_READY = 1,	/* hardware ready and netdev registered */
478 	STATE_DISABLED = 2,	/* device disabled due to hardware errors */
479 	STATE_RECOVERY = 3,	/* device recovering from PCI error */
480 };
481 
482 /*
483  * Alignment of the skb->head which wraps a page-allocated RX buffer
484  *
485  * The skb allocated to wrap an rx_buffer can have this alignment. Since
486  * the data is memcpy'd from the rx_buf, it does not need to be equal to
487  * NET_IP_ALIGN.
488  */
489 #define EFX_PAGE_SKB_ALIGN 2
490 
491 /* Forward declaration */
492 struct efx_nic;
493 
494 /* Pseudo bit-mask flow control field */
495 #define EFX_FC_RX	FLOW_CTRL_RX
496 #define EFX_FC_TX	FLOW_CTRL_TX
497 #define EFX_FC_AUTO	4
498 
499 /**
500  * struct efx_link_state - Current state of the link
501  * @up: Link is up
502  * @fd: Link is full-duplex
503  * @fc: Actual flow control flags
504  * @speed: Link speed (Mbps)
505  */
506 struct efx_link_state {
507 	bool up;
508 	bool fd;
509 	u8 fc;
510 	unsigned int speed;
511 };
512 
513 static inline bool efx_link_state_equal(const struct efx_link_state *left,
514 					const struct efx_link_state *right)
515 {
516 	return left->up == right->up && left->fd == right->fd &&
517 		left->fc == right->fc && left->speed == right->speed;
518 }
519 
520 /**
521  * struct efx_phy_operations - Efx PHY operations table
522  * @probe: Probe PHY and initialise efx->mdio.mode_support, efx->mdio.mmds,
523  *	efx->loopback_modes.
524  * @init: Initialise PHY
525  * @fini: Shut down PHY
526  * @reconfigure: Reconfigure PHY (e.g. for new link parameters)
527  * @poll: Update @link_state and report whether it changed.
528  *	Serialised by the mac_lock.
529  * @get_settings: Get ethtool settings. Serialised by the mac_lock.
530  * @set_settings: Set ethtool settings. Serialised by the mac_lock.
531  * @set_npage_adv: Set abilities advertised in (Extended) Next Page
532  *	(only needed where AN bit is set in mmds)
533  * @test_alive: Test that PHY is 'alive' (online)
534  * @test_name: Get the name of a PHY-specific test/result
535  * @run_tests: Run tests and record results as appropriate (offline).
536  *	Flags are the ethtool tests flags.
537  */
538 struct efx_phy_operations {
539 	int (*probe) (struct efx_nic *efx);
540 	int (*init) (struct efx_nic *efx);
541 	void (*fini) (struct efx_nic *efx);
542 	void (*remove) (struct efx_nic *efx);
543 	int (*reconfigure) (struct efx_nic *efx);
544 	bool (*poll) (struct efx_nic *efx);
545 	void (*get_settings) (struct efx_nic *efx,
546 			      struct ethtool_cmd *ecmd);
547 	int (*set_settings) (struct efx_nic *efx,
548 			     struct ethtool_cmd *ecmd);
549 	void (*set_npage_adv) (struct efx_nic *efx, u32);
550 	int (*test_alive) (struct efx_nic *efx);
551 	const char *(*test_name) (struct efx_nic *efx, unsigned int index);
552 	int (*run_tests) (struct efx_nic *efx, int *results, unsigned flags);
553 	int (*get_module_eeprom) (struct efx_nic *efx,
554 			       struct ethtool_eeprom *ee,
555 			       u8 *data);
556 	int (*get_module_info) (struct efx_nic *efx,
557 				struct ethtool_modinfo *modinfo);
558 };
559 
560 /**
561  * enum efx_phy_mode - PHY operating mode flags
562  * @PHY_MODE_NORMAL: on and should pass traffic
563  * @PHY_MODE_TX_DISABLED: on with TX disabled
564  * @PHY_MODE_LOW_POWER: set to low power through MDIO
565  * @PHY_MODE_OFF: switched off through external control
566  * @PHY_MODE_SPECIAL: on but will not pass traffic
567  */
568 enum efx_phy_mode {
569 	PHY_MODE_NORMAL		= 0,
570 	PHY_MODE_TX_DISABLED	= 1,
571 	PHY_MODE_LOW_POWER	= 2,
572 	PHY_MODE_OFF		= 4,
573 	PHY_MODE_SPECIAL	= 8,
574 };
575 
576 static inline bool efx_phy_mode_disabled(enum efx_phy_mode mode)
577 {
578 	return !!(mode & ~PHY_MODE_TX_DISABLED);
579 }
580 
581 /*
582  * Efx extended statistics
583  *
584  * Not all statistics are provided by all supported MACs.  The purpose
585  * is this structure is to contain the raw statistics provided by each
586  * MAC.
587  */
588 struct efx_mac_stats {
589 	u64 tx_bytes;
590 	u64 tx_good_bytes;
591 	u64 tx_bad_bytes;
592 	u64 tx_packets;
593 	u64 tx_bad;
594 	u64 tx_pause;
595 	u64 tx_control;
596 	u64 tx_unicast;
597 	u64 tx_multicast;
598 	u64 tx_broadcast;
599 	u64 tx_lt64;
600 	u64 tx_64;
601 	u64 tx_65_to_127;
602 	u64 tx_128_to_255;
603 	u64 tx_256_to_511;
604 	u64 tx_512_to_1023;
605 	u64 tx_1024_to_15xx;
606 	u64 tx_15xx_to_jumbo;
607 	u64 tx_gtjumbo;
608 	u64 tx_collision;
609 	u64 tx_single_collision;
610 	u64 tx_multiple_collision;
611 	u64 tx_excessive_collision;
612 	u64 tx_deferred;
613 	u64 tx_late_collision;
614 	u64 tx_excessive_deferred;
615 	u64 tx_non_tcpudp;
616 	u64 tx_mac_src_error;
617 	u64 tx_ip_src_error;
618 	u64 rx_bytes;
619 	u64 rx_good_bytes;
620 	u64 rx_bad_bytes;
621 	u64 rx_packets;
622 	u64 rx_good;
623 	u64 rx_bad;
624 	u64 rx_pause;
625 	u64 rx_control;
626 	u64 rx_unicast;
627 	u64 rx_multicast;
628 	u64 rx_broadcast;
629 	u64 rx_lt64;
630 	u64 rx_64;
631 	u64 rx_65_to_127;
632 	u64 rx_128_to_255;
633 	u64 rx_256_to_511;
634 	u64 rx_512_to_1023;
635 	u64 rx_1024_to_15xx;
636 	u64 rx_15xx_to_jumbo;
637 	u64 rx_gtjumbo;
638 	u64 rx_bad_lt64;
639 	u64 rx_bad_64_to_15xx;
640 	u64 rx_bad_15xx_to_jumbo;
641 	u64 rx_bad_gtjumbo;
642 	u64 rx_overflow;
643 	u64 rx_missed;
644 	u64 rx_false_carrier;
645 	u64 rx_symbol_error;
646 	u64 rx_align_error;
647 	u64 rx_length_error;
648 	u64 rx_internal_error;
649 	u64 rx_good_lt64;
650 };
651 
652 /* Number of bits used in a multicast filter hash address */
653 #define EFX_MCAST_HASH_BITS 8
654 
655 /* Number of (single-bit) entries in a multicast filter hash */
656 #define EFX_MCAST_HASH_ENTRIES (1 << EFX_MCAST_HASH_BITS)
657 
658 /* An Efx multicast filter hash */
659 union efx_multicast_hash {
660 	u8 byte[EFX_MCAST_HASH_ENTRIES / 8];
661 	efx_oword_t oword[EFX_MCAST_HASH_ENTRIES / sizeof(efx_oword_t) / 8];
662 };
663 
664 struct efx_filter_state;
665 struct efx_vf;
666 struct vfdi_status;
667 
668 /**
669  * struct efx_nic - an Efx NIC
670  * @name: Device name (net device name or bus id before net device registered)
671  * @pci_dev: The PCI device
672  * @type: Controller type attributes
673  * @legacy_irq: IRQ number
674  * @legacy_irq_enabled: Are IRQs enabled on NIC (INT_EN_KER register)?
675  * @workqueue: Workqueue for port reconfigures and the HW monitor.
676  *	Work items do not hold and must not acquire RTNL.
677  * @workqueue_name: Name of workqueue
678  * @reset_work: Scheduled reset workitem
679  * @membase_phys: Memory BAR value as physical address
680  * @membase: Memory BAR value
681  * @interrupt_mode: Interrupt mode
682  * @timer_quantum_ns: Interrupt timer quantum, in nanoseconds
683  * @irq_rx_adaptive: Adaptive IRQ moderation enabled for RX event queues
684  * @irq_rx_moderation: IRQ moderation time for RX event queues
685  * @msg_enable: Log message enable flags
686  * @state: Device state number (%STATE_*). Serialised by the rtnl_lock.
687  * @reset_pending: Bitmask for pending resets
688  * @tx_queue: TX DMA queues
689  * @rx_queue: RX DMA queues
690  * @channel: Channels
691  * @channel_name: Names for channels and their IRQs
692  * @extra_channel_types: Types of extra (non-traffic) channels that
693  *	should be allocated for this NIC
694  * @rxq_entries: Size of receive queues requested by user.
695  * @txq_entries: Size of transmit queues requested by user.
696  * @txq_stop_thresh: TX queue fill level at or above which we stop it.
697  * @txq_wake_thresh: TX queue fill level at or below which we wake it.
698  * @tx_dc_base: Base qword address in SRAM of TX queue descriptor caches
699  * @rx_dc_base: Base qword address in SRAM of RX queue descriptor caches
700  * @sram_lim_qw: Qword address limit of SRAM
701  * @next_buffer_table: First available buffer table id
702  * @n_channels: Number of channels in use
703  * @n_rx_channels: Number of channels used for RX (= number of RX queues)
704  * @n_tx_channels: Number of channels used for TX
705  * @rx_dma_len: Current maximum RX DMA length
706  * @rx_buffer_order: Order (log2) of number of pages for each RX buffer
707  * @rx_buffer_truesize: Amortised allocation size of an RX buffer,
708  *	for use in sk_buff::truesize
709  * @rx_hash_key: Toeplitz hash key for RSS
710  * @rx_indir_table: Indirection table for RSS
711  * @rx_scatter: Scatter mode enabled for receives
712  * @int_error_count: Number of internal errors seen recently
713  * @int_error_expire: Time at which error count will be expired
714  * @irq_status: Interrupt status buffer
715  * @irq_zero_count: Number of legacy IRQs seen with queue flags == 0
716  * @irq_level: IRQ level/index for IRQs not triggered by an event queue
717  * @selftest_work: Work item for asynchronous self-test
718  * @mtd_list: List of MTDs attached to the NIC
719  * @nic_data: Hardware dependent state
720  * @mac_lock: MAC access lock. Protects @port_enabled, @phy_mode,
721  *	efx_monitor() and efx_reconfigure_port()
722  * @port_enabled: Port enabled indicator.
723  *	Serialises efx_stop_all(), efx_start_all(), efx_monitor() and
724  *	efx_mac_work() with kernel interfaces. Safe to read under any
725  *	one of the rtnl_lock, mac_lock, or netif_tx_lock, but all three must
726  *	be held to modify it.
727  * @port_initialized: Port initialized?
728  * @net_dev: Operating system network device. Consider holding the rtnl lock
729  * @stats_buffer: DMA buffer for statistics
730  * @phy_type: PHY type
731  * @phy_op: PHY interface
732  * @phy_data: PHY private data (including PHY-specific stats)
733  * @mdio: PHY MDIO interface
734  * @mdio_bus: PHY MDIO bus ID (only used by Siena)
735  * @phy_mode: PHY operating mode. Serialised by @mac_lock.
736  * @link_advertising: Autonegotiation advertising flags
737  * @link_state: Current state of the link
738  * @n_link_state_changes: Number of times the link has changed state
739  * @promiscuous: Promiscuous flag. Protected by netif_tx_lock.
740  * @multicast_hash: Multicast hash table
741  * @wanted_fc: Wanted flow control flags
742  * @fc_disable: When non-zero flow control is disabled. Typically used to
743  *	ensure that network back pressure doesn't delay dma queue flushes.
744  *	Serialised by the rtnl lock.
745  * @mac_work: Work item for changing MAC promiscuity and multicast hash
746  * @loopback_mode: Loopback status
747  * @loopback_modes: Supported loopback mode bitmask
748  * @loopback_selftest: Offline self-test private state
749  * @drain_pending: Count of RX and TX queues that haven't been flushed and drained.
750  * @rxq_flush_pending: Count of number of receive queues that need to be flushed.
751  *	Decremented when the efx_flush_rx_queue() is called.
752  * @rxq_flush_outstanding: Count of number of RX flushes started but not yet
753  *	completed (either success or failure). Not used when MCDI is used to
754  *	flush receive queues.
755  * @flush_wq: wait queue used by efx_nic_flush_queues() to wait for flush completions.
756  * @vf: Array of &struct efx_vf objects.
757  * @vf_count: Number of VFs intended to be enabled.
758  * @vf_init_count: Number of VFs that have been fully initialised.
759  * @vi_scale: log2 number of vnics per VF.
760  * @vf_buftbl_base: The zeroth buffer table index used to back VF queues.
761  * @vfdi_status: Common VFDI status page to be dmad to VF address space.
762  * @local_addr_list: List of local addresses. Protected by %local_lock.
763  * @local_page_list: List of DMA addressable pages used to broadcast
764  *	%local_addr_list. Protected by %local_lock.
765  * @local_lock: Mutex protecting %local_addr_list and %local_page_list.
766  * @peer_work: Work item to broadcast peer addresses to VMs.
767  * @ptp_data: PTP state data
768  * @monitor_work: Hardware monitor workitem
769  * @biu_lock: BIU (bus interface unit) lock
770  * @last_irq_cpu: Last CPU to handle a possible test interrupt.  This
771  *	field is used by efx_test_interrupts() to verify that an
772  *	interrupt has occurred.
773  * @n_rx_nodesc_drop_cnt: RX no descriptor drop count
774  * @mac_stats: MAC statistics. These include all statistics the MACs
775  *	can provide.  Generic code converts these into a standard
776  *	&struct net_device_stats.
777  * @stats_lock: Statistics update lock. Serialises statistics fetches
778  *	and access to @mac_stats.
779  *
780  * This is stored in the private area of the &struct net_device.
781  */
782 struct efx_nic {
783 	/* The following fields should be written very rarely */
784 
785 	char name[IFNAMSIZ];
786 	struct pci_dev *pci_dev;
787 	const struct efx_nic_type *type;
788 	int legacy_irq;
789 	bool legacy_irq_enabled;
790 	struct workqueue_struct *workqueue;
791 	char workqueue_name[16];
792 	struct work_struct reset_work;
793 	resource_size_t membase_phys;
794 	void __iomem *membase;
795 
796 	enum efx_int_mode interrupt_mode;
797 	unsigned int timer_quantum_ns;
798 	bool irq_rx_adaptive;
799 	unsigned int irq_rx_moderation;
800 	u32 msg_enable;
801 
802 	enum nic_state state;
803 	unsigned long reset_pending;
804 
805 	struct efx_channel *channel[EFX_MAX_CHANNELS];
806 	char channel_name[EFX_MAX_CHANNELS][IFNAMSIZ + 6];
807 	const struct efx_channel_type *
808 	extra_channel_type[EFX_MAX_EXTRA_CHANNELS];
809 
810 	unsigned rxq_entries;
811 	unsigned txq_entries;
812 	unsigned int txq_stop_thresh;
813 	unsigned int txq_wake_thresh;
814 
815 	unsigned tx_dc_base;
816 	unsigned rx_dc_base;
817 	unsigned sram_lim_qw;
818 	unsigned next_buffer_table;
819 	unsigned n_channels;
820 	unsigned n_rx_channels;
821 	unsigned rss_spread;
822 	unsigned tx_channel_offset;
823 	unsigned n_tx_channels;
824 	unsigned int rx_dma_len;
825 	unsigned int rx_buffer_order;
826 	unsigned int rx_buffer_truesize;
827 	unsigned int rx_page_buf_step;
828 	unsigned int rx_bufs_per_page;
829 	unsigned int rx_pages_per_batch;
830 	u8 rx_hash_key[40];
831 	u32 rx_indir_table[128];
832 	bool rx_scatter;
833 
834 	unsigned int_error_count;
835 	unsigned long int_error_expire;
836 
837 	struct efx_buffer irq_status;
838 	unsigned irq_zero_count;
839 	unsigned irq_level;
840 	struct delayed_work selftest_work;
841 
842 #ifdef CONFIG_SFC_MTD
843 	struct list_head mtd_list;
844 #endif
845 
846 	void *nic_data;
847 
848 	struct mutex mac_lock;
849 	struct work_struct mac_work;
850 	bool port_enabled;
851 
852 	bool port_initialized;
853 	struct net_device *net_dev;
854 
855 	struct efx_buffer stats_buffer;
856 
857 	unsigned int phy_type;
858 	const struct efx_phy_operations *phy_op;
859 	void *phy_data;
860 	struct mdio_if_info mdio;
861 	unsigned int mdio_bus;
862 	enum efx_phy_mode phy_mode;
863 
864 	u32 link_advertising;
865 	struct efx_link_state link_state;
866 	unsigned int n_link_state_changes;
867 
868 	bool promiscuous;
869 	union efx_multicast_hash multicast_hash;
870 	u8 wanted_fc;
871 	unsigned fc_disable;
872 
873 	atomic_t rx_reset;
874 	enum efx_loopback_mode loopback_mode;
875 	u64 loopback_modes;
876 
877 	void *loopback_selftest;
878 
879 	struct efx_filter_state *filter_state;
880 
881 	atomic_t drain_pending;
882 	atomic_t rxq_flush_pending;
883 	atomic_t rxq_flush_outstanding;
884 	wait_queue_head_t flush_wq;
885 
886 #ifdef CONFIG_SFC_SRIOV
887 	struct efx_channel *vfdi_channel;
888 	struct efx_vf *vf;
889 	unsigned vf_count;
890 	unsigned vf_init_count;
891 	unsigned vi_scale;
892 	unsigned vf_buftbl_base;
893 	struct efx_buffer vfdi_status;
894 	struct list_head local_addr_list;
895 	struct list_head local_page_list;
896 	struct mutex local_lock;
897 	struct work_struct peer_work;
898 #endif
899 
900 	struct efx_ptp_data *ptp_data;
901 
902 	/* The following fields may be written more often */
903 
904 	struct delayed_work monitor_work ____cacheline_aligned_in_smp;
905 	spinlock_t biu_lock;
906 	int last_irq_cpu;
907 	unsigned n_rx_nodesc_drop_cnt;
908 	struct efx_mac_stats mac_stats;
909 	spinlock_t stats_lock;
910 };
911 
912 static inline int efx_dev_registered(struct efx_nic *efx)
913 {
914 	return efx->net_dev->reg_state == NETREG_REGISTERED;
915 }
916 
917 static inline unsigned int efx_port_num(struct efx_nic *efx)
918 {
919 	return efx->net_dev->dev_id;
920 }
921 
922 /**
923  * struct efx_nic_type - Efx device type definition
924  * @probe: Probe the controller
925  * @remove: Free resources allocated by probe()
926  * @init: Initialise the controller
927  * @dimension_resources: Dimension controller resources (buffer table,
928  *	and VIs once the available interrupt resources are clear)
929  * @fini: Shut down the controller
930  * @monitor: Periodic function for polling link state and hardware monitor
931  * @map_reset_reason: Map ethtool reset reason to a reset method
932  * @map_reset_flags: Map ethtool reset flags to a reset method, if possible
933  * @reset: Reset the controller hardware and possibly the PHY.  This will
934  *	be called while the controller is uninitialised.
935  * @probe_port: Probe the MAC and PHY
936  * @remove_port: Free resources allocated by probe_port()
937  * @handle_global_event: Handle a "global" event (may be %NULL)
938  * @prepare_flush: Prepare the hardware for flushing the DMA queues
939  * @finish_flush: Clean up after flushing the DMA queues
940  * @update_stats: Update statistics not provided by event handling
941  * @start_stats: Start the regular fetching of statistics
942  * @stop_stats: Stop the regular fetching of statistics
943  * @set_id_led: Set state of identifying LED or revert to automatic function
944  * @push_irq_moderation: Apply interrupt moderation value
945  * @reconfigure_port: Push loopback/power/txdis changes to the MAC and PHY
946  * @reconfigure_mac: Push MAC address, MTU, flow control and filter settings
947  *	to the hardware.  Serialised by the mac_lock.
948  * @check_mac_fault: Check MAC fault state. True if fault present.
949  * @get_wol: Get WoL configuration from driver state
950  * @set_wol: Push WoL configuration to the NIC
951  * @resume_wol: Synchronise WoL state between driver and MC (e.g. after resume)
952  * @test_chip: Test registers.  Should use efx_nic_test_registers(), and is
953  *	expected to reset the NIC.
954  * @test_nvram: Test validity of NVRAM contents
955  * @revision: Hardware architecture revision
956  * @mem_map_size: Memory BAR mapped size
957  * @txd_ptr_tbl_base: TX descriptor ring base address
958  * @rxd_ptr_tbl_base: RX descriptor ring base address
959  * @buf_tbl_base: Buffer table base address
960  * @evq_ptr_tbl_base: Event queue pointer table base address
961  * @evq_rptr_tbl_base: Event queue read-pointer table base address
962  * @max_dma_mask: Maximum possible DMA mask
963  * @rx_buffer_hash_size: Size of hash at start of RX packet
964  * @rx_buffer_padding: Size of padding at end of RX packet
965  * @can_rx_scatter: NIC is able to scatter packet to multiple buffers
966  * @max_interrupt_mode: Highest capability interrupt mode supported
967  *	from &enum efx_init_mode.
968  * @phys_addr_channels: Number of channels with physically addressed
969  *	descriptors
970  * @timer_period_max: Maximum period of interrupt timer (in ticks)
971  * @offload_features: net_device feature flags for protocol offload
972  *	features implemented in hardware
973  */
974 struct efx_nic_type {
975 	int (*probe)(struct efx_nic *efx);
976 	void (*remove)(struct efx_nic *efx);
977 	int (*init)(struct efx_nic *efx);
978 	void (*dimension_resources)(struct efx_nic *efx);
979 	void (*fini)(struct efx_nic *efx);
980 	void (*monitor)(struct efx_nic *efx);
981 	enum reset_type (*map_reset_reason)(enum reset_type reason);
982 	int (*map_reset_flags)(u32 *flags);
983 	int (*reset)(struct efx_nic *efx, enum reset_type method);
984 	int (*probe_port)(struct efx_nic *efx);
985 	void (*remove_port)(struct efx_nic *efx);
986 	bool (*handle_global_event)(struct efx_channel *channel, efx_qword_t *);
987 	void (*prepare_flush)(struct efx_nic *efx);
988 	void (*finish_flush)(struct efx_nic *efx);
989 	void (*update_stats)(struct efx_nic *efx);
990 	void (*start_stats)(struct efx_nic *efx);
991 	void (*stop_stats)(struct efx_nic *efx);
992 	void (*set_id_led)(struct efx_nic *efx, enum efx_led_mode mode);
993 	void (*push_irq_moderation)(struct efx_channel *channel);
994 	int (*reconfigure_port)(struct efx_nic *efx);
995 	int (*reconfigure_mac)(struct efx_nic *efx);
996 	bool (*check_mac_fault)(struct efx_nic *efx);
997 	void (*get_wol)(struct efx_nic *efx, struct ethtool_wolinfo *wol);
998 	int (*set_wol)(struct efx_nic *efx, u32 type);
999 	void (*resume_wol)(struct efx_nic *efx);
1000 	int (*test_chip)(struct efx_nic *efx, struct efx_self_tests *tests);
1001 	int (*test_nvram)(struct efx_nic *efx);
1002 
1003 	int revision;
1004 	unsigned int mem_map_size;
1005 	unsigned int txd_ptr_tbl_base;
1006 	unsigned int rxd_ptr_tbl_base;
1007 	unsigned int buf_tbl_base;
1008 	unsigned int evq_ptr_tbl_base;
1009 	unsigned int evq_rptr_tbl_base;
1010 	u64 max_dma_mask;
1011 	unsigned int rx_buffer_hash_size;
1012 	unsigned int rx_buffer_padding;
1013 	bool can_rx_scatter;
1014 	unsigned int max_interrupt_mode;
1015 	unsigned int phys_addr_channels;
1016 	unsigned int timer_period_max;
1017 	netdev_features_t offload_features;
1018 };
1019 
1020 /**************************************************************************
1021  *
1022  * Prototypes and inline functions
1023  *
1024  *************************************************************************/
1025 
1026 static inline struct efx_channel *
1027 efx_get_channel(struct efx_nic *efx, unsigned index)
1028 {
1029 	EFX_BUG_ON_PARANOID(index >= efx->n_channels);
1030 	return efx->channel[index];
1031 }
1032 
1033 /* Iterate over all used channels */
1034 #define efx_for_each_channel(_channel, _efx)				\
1035 	for (_channel = (_efx)->channel[0];				\
1036 	     _channel;							\
1037 	     _channel = (_channel->channel + 1 < (_efx)->n_channels) ?	\
1038 		     (_efx)->channel[_channel->channel + 1] : NULL)
1039 
1040 /* Iterate over all used channels in reverse */
1041 #define efx_for_each_channel_rev(_channel, _efx)			\
1042 	for (_channel = (_efx)->channel[(_efx)->n_channels - 1];	\
1043 	     _channel;							\
1044 	     _channel = _channel->channel ?				\
1045 		     (_efx)->channel[_channel->channel - 1] : NULL)
1046 
1047 static inline struct efx_tx_queue *
1048 efx_get_tx_queue(struct efx_nic *efx, unsigned index, unsigned type)
1049 {
1050 	EFX_BUG_ON_PARANOID(index >= efx->n_tx_channels ||
1051 			    type >= EFX_TXQ_TYPES);
1052 	return &efx->channel[efx->tx_channel_offset + index]->tx_queue[type];
1053 }
1054 
1055 static inline bool efx_channel_has_tx_queues(struct efx_channel *channel)
1056 {
1057 	return channel->channel - channel->efx->tx_channel_offset <
1058 		channel->efx->n_tx_channels;
1059 }
1060 
1061 static inline struct efx_tx_queue *
1062 efx_channel_get_tx_queue(struct efx_channel *channel, unsigned type)
1063 {
1064 	EFX_BUG_ON_PARANOID(!efx_channel_has_tx_queues(channel) ||
1065 			    type >= EFX_TXQ_TYPES);
1066 	return &channel->tx_queue[type];
1067 }
1068 
1069 static inline bool efx_tx_queue_used(struct efx_tx_queue *tx_queue)
1070 {
1071 	return !(tx_queue->efx->net_dev->num_tc < 2 &&
1072 		 tx_queue->queue & EFX_TXQ_TYPE_HIGHPRI);
1073 }
1074 
1075 /* Iterate over all TX queues belonging to a channel */
1076 #define efx_for_each_channel_tx_queue(_tx_queue, _channel)		\
1077 	if (!efx_channel_has_tx_queues(_channel))			\
1078 		;							\
1079 	else								\
1080 		for (_tx_queue = (_channel)->tx_queue;			\
1081 		     _tx_queue < (_channel)->tx_queue + EFX_TXQ_TYPES && \
1082 			     efx_tx_queue_used(_tx_queue);		\
1083 		     _tx_queue++)
1084 
1085 /* Iterate over all possible TX queues belonging to a channel */
1086 #define efx_for_each_possible_channel_tx_queue(_tx_queue, _channel)	\
1087 	if (!efx_channel_has_tx_queues(_channel))			\
1088 		;							\
1089 	else								\
1090 		for (_tx_queue = (_channel)->tx_queue;			\
1091 		     _tx_queue < (_channel)->tx_queue + EFX_TXQ_TYPES;	\
1092 		     _tx_queue++)
1093 
1094 static inline bool efx_channel_has_rx_queue(struct efx_channel *channel)
1095 {
1096 	return channel->rx_queue.core_index >= 0;
1097 }
1098 
1099 static inline struct efx_rx_queue *
1100 efx_channel_get_rx_queue(struct efx_channel *channel)
1101 {
1102 	EFX_BUG_ON_PARANOID(!efx_channel_has_rx_queue(channel));
1103 	return &channel->rx_queue;
1104 }
1105 
1106 /* Iterate over all RX queues belonging to a channel */
1107 #define efx_for_each_channel_rx_queue(_rx_queue, _channel)		\
1108 	if (!efx_channel_has_rx_queue(_channel))			\
1109 		;							\
1110 	else								\
1111 		for (_rx_queue = &(_channel)->rx_queue;			\
1112 		     _rx_queue;						\
1113 		     _rx_queue = NULL)
1114 
1115 static inline struct efx_channel *
1116 efx_rx_queue_channel(struct efx_rx_queue *rx_queue)
1117 {
1118 	return container_of(rx_queue, struct efx_channel, rx_queue);
1119 }
1120 
1121 static inline int efx_rx_queue_index(struct efx_rx_queue *rx_queue)
1122 {
1123 	return efx_rx_queue_channel(rx_queue)->channel;
1124 }
1125 
1126 /* Returns a pointer to the specified receive buffer in the RX
1127  * descriptor queue.
1128  */
1129 static inline struct efx_rx_buffer *efx_rx_buffer(struct efx_rx_queue *rx_queue,
1130 						  unsigned int index)
1131 {
1132 	return &rx_queue->buffer[index];
1133 }
1134 
1135 
1136 /**
1137  * EFX_MAX_FRAME_LEN - calculate maximum frame length
1138  *
1139  * This calculates the maximum frame length that will be used for a
1140  * given MTU.  The frame length will be equal to the MTU plus a
1141  * constant amount of header space and padding.  This is the quantity
1142  * that the net driver will program into the MAC as the maximum frame
1143  * length.
1144  *
1145  * The 10G MAC requires 8-byte alignment on the frame
1146  * length, so we round up to the nearest 8.
1147  *
1148  * Re-clocking by the XGXS on RX can reduce an IPG to 32 bits (half an
1149  * XGMII cycle).  If the frame length reaches the maximum value in the
1150  * same cycle, the XMAC can miss the IPG altogether.  We work around
1151  * this by adding a further 16 bytes.
1152  */
1153 #define EFX_MAX_FRAME_LEN(mtu) \
1154 	((((mtu) + ETH_HLEN + VLAN_HLEN + 4/* FCS */ + 7) & ~7) + 16)
1155 
1156 static inline bool efx_xmit_with_hwtstamp(struct sk_buff *skb)
1157 {
1158 	return skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP;
1159 }
1160 static inline void efx_xmit_hwtstamp_pending(struct sk_buff *skb)
1161 {
1162 	skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
1163 }
1164 
1165 #endif /* EFX_NET_DRIVER_H */
1166