1 /*
2  * Copyright (C) 2015-2017 Netronome Systems, Inc.
3  *
4  * This software is dual licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree or the BSD 2-Clause License provided below.  You have the
7  * option to license this software under the complete terms of either license.
8  *
9  * The BSD 2-Clause License:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      1. Redistributions of source code must retain the above
16  *         copyright notice, this list of conditions and the following
17  *         disclaimer.
18  *
19  *      2. Redistributions in binary form must reproduce the above
20  *         copyright notice, this list of conditions and the following
21  *         disclaimer in the documentation and/or other materials
22  *         provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 /*
35  * nfp_net_common.c
36  * Netronome network device driver: Common functions between PF and VF
37  * Authors: Jakub Kicinski <jakub.kicinski@netronome.com>
38  *          Jason McMullan <jason.mcmullan@netronome.com>
39  *          Rolf Neugebauer <rolf.neugebauer@netronome.com>
40  *          Brad Petrus <brad.petrus@netronome.com>
41  *          Chris Telfer <chris.telfer@netronome.com>
42  */
43 
44 #include <linux/bpf.h>
45 #include <linux/bpf_trace.h>
46 #include <linux/module.h>
47 #include <linux/kernel.h>
48 #include <linux/init.h>
49 #include <linux/fs.h>
50 #include <linux/netdevice.h>
51 #include <linux/etherdevice.h>
52 #include <linux/interrupt.h>
53 #include <linux/ip.h>
54 #include <linux/ipv6.h>
55 #include <linux/page_ref.h>
56 #include <linux/pci.h>
57 #include <linux/pci_regs.h>
58 #include <linux/msi.h>
59 #include <linux/ethtool.h>
60 #include <linux/log2.h>
61 #include <linux/if_vlan.h>
62 #include <linux/random.h>
63 
64 #include <linux/ktime.h>
65 
66 #include <net/pkt_cls.h>
67 #include <net/vxlan.h>
68 
69 #include "nfp_net_ctrl.h"
70 #include "nfp_net.h"
71 
72 /**
73  * nfp_net_get_fw_version() - Read and parse the FW version
74  * @fw_ver:	Output fw_version structure to read to
75  * @ctrl_bar:	Mapped address of the control BAR
76  */
77 void nfp_net_get_fw_version(struct nfp_net_fw_version *fw_ver,
78 			    void __iomem *ctrl_bar)
79 {
80 	u32 reg;
81 
82 	reg = readl(ctrl_bar + NFP_NET_CFG_VERSION);
83 	put_unaligned_le32(reg, fw_ver);
84 }
85 
86 static dma_addr_t
87 nfp_net_dma_map_rx(struct nfp_net *nn, void *frag, unsigned int bufsz,
88 		   int direction)
89 {
90 	return dma_map_single(&nn->pdev->dev, frag + NFP_NET_RX_BUF_HEADROOM,
91 			      bufsz - NFP_NET_RX_BUF_NON_DATA, direction);
92 }
93 
94 static void
95 nfp_net_dma_unmap_rx(struct nfp_net *nn, dma_addr_t dma_addr,
96 		     unsigned int bufsz, int direction)
97 {
98 	dma_unmap_single(&nn->pdev->dev, dma_addr,
99 			 bufsz - NFP_NET_RX_BUF_NON_DATA, direction);
100 }
101 
102 /* Firmware reconfig
103  *
104  * Firmware reconfig may take a while so we have two versions of it -
105  * synchronous and asynchronous (posted).  All synchronous callers are holding
106  * RTNL so we don't have to worry about serializing them.
107  */
108 static void nfp_net_reconfig_start(struct nfp_net *nn, u32 update)
109 {
110 	nn_writel(nn, NFP_NET_CFG_UPDATE, update);
111 	/* ensure update is written before pinging HW */
112 	nn_pci_flush(nn);
113 	nfp_qcp_wr_ptr_add(nn->qcp_cfg, 1);
114 }
115 
116 /* Pass 0 as update to run posted reconfigs. */
117 static void nfp_net_reconfig_start_async(struct nfp_net *nn, u32 update)
118 {
119 	update |= nn->reconfig_posted;
120 	nn->reconfig_posted = 0;
121 
122 	nfp_net_reconfig_start(nn, update);
123 
124 	nn->reconfig_timer_active = true;
125 	mod_timer(&nn->reconfig_timer, jiffies + NFP_NET_POLL_TIMEOUT * HZ);
126 }
127 
128 static bool nfp_net_reconfig_check_done(struct nfp_net *nn, bool last_check)
129 {
130 	u32 reg;
131 
132 	reg = nn_readl(nn, NFP_NET_CFG_UPDATE);
133 	if (reg == 0)
134 		return true;
135 	if (reg & NFP_NET_CFG_UPDATE_ERR) {
136 		nn_err(nn, "Reconfig error: 0x%08x\n", reg);
137 		return true;
138 	} else if (last_check) {
139 		nn_err(nn, "Reconfig timeout: 0x%08x\n", reg);
140 		return true;
141 	}
142 
143 	return false;
144 }
145 
146 static int nfp_net_reconfig_wait(struct nfp_net *nn, unsigned long deadline)
147 {
148 	bool timed_out = false;
149 
150 	/* Poll update field, waiting for NFP to ack the config */
151 	while (!nfp_net_reconfig_check_done(nn, timed_out)) {
152 		msleep(1);
153 		timed_out = time_is_before_eq_jiffies(deadline);
154 	}
155 
156 	if (nn_readl(nn, NFP_NET_CFG_UPDATE) & NFP_NET_CFG_UPDATE_ERR)
157 		return -EIO;
158 
159 	return timed_out ? -EIO : 0;
160 }
161 
162 static void nfp_net_reconfig_timer(unsigned long data)
163 {
164 	struct nfp_net *nn = (void *)data;
165 
166 	spin_lock_bh(&nn->reconfig_lock);
167 
168 	nn->reconfig_timer_active = false;
169 
170 	/* If sync caller is present it will take over from us */
171 	if (nn->reconfig_sync_present)
172 		goto done;
173 
174 	/* Read reconfig status and report errors */
175 	nfp_net_reconfig_check_done(nn, true);
176 
177 	if (nn->reconfig_posted)
178 		nfp_net_reconfig_start_async(nn, 0);
179 done:
180 	spin_unlock_bh(&nn->reconfig_lock);
181 }
182 
183 /**
184  * nfp_net_reconfig_post() - Post async reconfig request
185  * @nn:      NFP Net device to reconfigure
186  * @update:  The value for the update field in the BAR config
187  *
188  * Record FW reconfiguration request.  Reconfiguration will be kicked off
189  * whenever reconfiguration machinery is idle.  Multiple requests can be
190  * merged together!
191  */
192 static void nfp_net_reconfig_post(struct nfp_net *nn, u32 update)
193 {
194 	spin_lock_bh(&nn->reconfig_lock);
195 
196 	/* Sync caller will kick off async reconf when it's done, just post */
197 	if (nn->reconfig_sync_present) {
198 		nn->reconfig_posted |= update;
199 		goto done;
200 	}
201 
202 	/* Opportunistically check if the previous command is done */
203 	if (!nn->reconfig_timer_active ||
204 	    nfp_net_reconfig_check_done(nn, false))
205 		nfp_net_reconfig_start_async(nn, update);
206 	else
207 		nn->reconfig_posted |= update;
208 done:
209 	spin_unlock_bh(&nn->reconfig_lock);
210 }
211 
212 /**
213  * nfp_net_reconfig() - Reconfigure the firmware
214  * @nn:      NFP Net device to reconfigure
215  * @update:  The value for the update field in the BAR config
216  *
217  * Write the update word to the BAR and ping the reconfig queue.  The
218  * poll until the firmware has acknowledged the update by zeroing the
219  * update word.
220  *
221  * Return: Negative errno on error, 0 on success
222  */
223 int nfp_net_reconfig(struct nfp_net *nn, u32 update)
224 {
225 	bool cancelled_timer = false;
226 	u32 pre_posted_requests;
227 	int ret;
228 
229 	spin_lock_bh(&nn->reconfig_lock);
230 
231 	nn->reconfig_sync_present = true;
232 
233 	if (nn->reconfig_timer_active) {
234 		del_timer(&nn->reconfig_timer);
235 		nn->reconfig_timer_active = false;
236 		cancelled_timer = true;
237 	}
238 	pre_posted_requests = nn->reconfig_posted;
239 	nn->reconfig_posted = 0;
240 
241 	spin_unlock_bh(&nn->reconfig_lock);
242 
243 	if (cancelled_timer)
244 		nfp_net_reconfig_wait(nn, nn->reconfig_timer.expires);
245 
246 	/* Run the posted reconfigs which were issued before we started */
247 	if (pre_posted_requests) {
248 		nfp_net_reconfig_start(nn, pre_posted_requests);
249 		nfp_net_reconfig_wait(nn, jiffies + HZ * NFP_NET_POLL_TIMEOUT);
250 	}
251 
252 	nfp_net_reconfig_start(nn, update);
253 	ret = nfp_net_reconfig_wait(nn, jiffies + HZ * NFP_NET_POLL_TIMEOUT);
254 
255 	spin_lock_bh(&nn->reconfig_lock);
256 
257 	if (nn->reconfig_posted)
258 		nfp_net_reconfig_start_async(nn, 0);
259 
260 	nn->reconfig_sync_present = false;
261 
262 	spin_unlock_bh(&nn->reconfig_lock);
263 
264 	return ret;
265 }
266 
267 /* Interrupt configuration and handling
268  */
269 
270 /**
271  * nfp_net_irq_unmask() - Unmask automasked interrupt
272  * @nn:       NFP Network structure
273  * @entry_nr: MSI-X table entry
274  *
275  * Clear the ICR for the IRQ entry.
276  */
277 static void nfp_net_irq_unmask(struct nfp_net *nn, unsigned int entry_nr)
278 {
279 	nn_writeb(nn, NFP_NET_CFG_ICR(entry_nr), NFP_NET_CFG_ICR_UNMASKED);
280 	nn_pci_flush(nn);
281 }
282 
283 /**
284  * nfp_net_irqs_alloc() - allocates MSI-X irqs
285  * @pdev:        PCI device structure
286  * @irq_entries: Array to be initialized and used to hold the irq entries
287  * @min_irqs:    Minimal acceptable number of interrupts
288  * @wanted_irqs: Target number of interrupts to allocate
289  *
290  * Return: Number of irqs obtained or 0 on error.
291  */
292 unsigned int
293 nfp_net_irqs_alloc(struct pci_dev *pdev, struct msix_entry *irq_entries,
294 		   unsigned int min_irqs, unsigned int wanted_irqs)
295 {
296 	unsigned int i;
297 	int got_irqs;
298 
299 	for (i = 0; i < wanted_irqs; i++)
300 		irq_entries[i].entry = i;
301 
302 	got_irqs = pci_enable_msix_range(pdev, irq_entries,
303 					 min_irqs, wanted_irqs);
304 	if (got_irqs < 0) {
305 		dev_err(&pdev->dev, "Failed to enable %d-%d MSI-X (err=%d)\n",
306 			min_irqs, wanted_irqs, got_irqs);
307 		return 0;
308 	}
309 
310 	if (got_irqs < wanted_irqs)
311 		dev_warn(&pdev->dev, "Unable to allocate %d IRQs got only %d\n",
312 			 wanted_irqs, got_irqs);
313 
314 	return got_irqs;
315 }
316 
317 /**
318  * nfp_net_irqs_assign() - Assign interrupts allocated externally to netdev
319  * @nn:		 NFP Network structure
320  * @irq_entries: Table of allocated interrupts
321  * @n:		 Size of @irq_entries (number of entries to grab)
322  *
323  * After interrupts are allocated with nfp_net_irqs_alloc() this function
324  * should be called to assign them to a specific netdev (port).
325  */
326 void
327 nfp_net_irqs_assign(struct nfp_net *nn, struct msix_entry *irq_entries,
328 		    unsigned int n)
329 {
330 	nn->max_r_vecs = n - NFP_NET_NON_Q_VECTORS;
331 	nn->num_r_vecs = nn->max_r_vecs;
332 
333 	memcpy(nn->irq_entries, irq_entries, sizeof(*irq_entries) * n);
334 
335 	if (nn->num_rx_rings > nn->num_r_vecs ||
336 	    nn->num_tx_rings > nn->num_r_vecs)
337 		nn_warn(nn, "More rings (%d,%d) than vectors (%d).\n",
338 			nn->num_rx_rings, nn->num_tx_rings, nn->num_r_vecs);
339 
340 	nn->num_rx_rings = min(nn->num_r_vecs, nn->num_rx_rings);
341 	nn->num_tx_rings = min(nn->num_r_vecs, nn->num_tx_rings);
342 	nn->num_stack_tx_rings = nn->num_tx_rings;
343 }
344 
345 /**
346  * nfp_net_irqs_disable() - Disable interrupts
347  * @pdev:        PCI device structure
348  *
349  * Undoes what @nfp_net_irqs_alloc() does.
350  */
351 void nfp_net_irqs_disable(struct pci_dev *pdev)
352 {
353 	pci_disable_msix(pdev);
354 }
355 
356 /**
357  * nfp_net_irq_rxtx() - Interrupt service routine for RX/TX rings.
358  * @irq:      Interrupt
359  * @data:     Opaque data structure
360  *
361  * Return: Indicate if the interrupt has been handled.
362  */
363 static irqreturn_t nfp_net_irq_rxtx(int irq, void *data)
364 {
365 	struct nfp_net_r_vector *r_vec = data;
366 
367 	napi_schedule_irqoff(&r_vec->napi);
368 
369 	/* The FW auto-masks any interrupt, either via the MASK bit in
370 	 * the MSI-X table or via the per entry ICR field.  So there
371 	 * is no need to disable interrupts here.
372 	 */
373 	return IRQ_HANDLED;
374 }
375 
376 /**
377  * nfp_net_read_link_status() - Reread link status from control BAR
378  * @nn:       NFP Network structure
379  */
380 static void nfp_net_read_link_status(struct nfp_net *nn)
381 {
382 	unsigned long flags;
383 	bool link_up;
384 	u32 sts;
385 
386 	spin_lock_irqsave(&nn->link_status_lock, flags);
387 
388 	sts = nn_readl(nn, NFP_NET_CFG_STS);
389 	link_up = !!(sts & NFP_NET_CFG_STS_LINK);
390 
391 	if (nn->link_up == link_up)
392 		goto out;
393 
394 	nn->link_up = link_up;
395 
396 	if (nn->link_up) {
397 		netif_carrier_on(nn->netdev);
398 		netdev_info(nn->netdev, "NIC Link is Up\n");
399 	} else {
400 		netif_carrier_off(nn->netdev);
401 		netdev_info(nn->netdev, "NIC Link is Down\n");
402 	}
403 out:
404 	spin_unlock_irqrestore(&nn->link_status_lock, flags);
405 }
406 
407 /**
408  * nfp_net_irq_lsc() - Interrupt service routine for link state changes
409  * @irq:      Interrupt
410  * @data:     Opaque data structure
411  *
412  * Return: Indicate if the interrupt has been handled.
413  */
414 static irqreturn_t nfp_net_irq_lsc(int irq, void *data)
415 {
416 	struct nfp_net *nn = data;
417 	struct msix_entry *entry;
418 
419 	entry = &nn->irq_entries[NFP_NET_IRQ_LSC_IDX];
420 
421 	nfp_net_read_link_status(nn);
422 
423 	nfp_net_irq_unmask(nn, entry->entry);
424 
425 	return IRQ_HANDLED;
426 }
427 
428 /**
429  * nfp_net_irq_exn() - Interrupt service routine for exceptions
430  * @irq:      Interrupt
431  * @data:     Opaque data structure
432  *
433  * Return: Indicate if the interrupt has been handled.
434  */
435 static irqreturn_t nfp_net_irq_exn(int irq, void *data)
436 {
437 	struct nfp_net *nn = data;
438 
439 	nn_err(nn, "%s: UNIMPLEMENTED.\n", __func__);
440 	/* XXX TO BE IMPLEMENTED */
441 	return IRQ_HANDLED;
442 }
443 
444 /**
445  * nfp_net_tx_ring_init() - Fill in the boilerplate for a TX ring
446  * @tx_ring:  TX ring structure
447  * @r_vec:    IRQ vector servicing this ring
448  * @idx:      Ring index
449  */
450 static void
451 nfp_net_tx_ring_init(struct nfp_net_tx_ring *tx_ring,
452 		     struct nfp_net_r_vector *r_vec, unsigned int idx)
453 {
454 	struct nfp_net *nn = r_vec->nfp_net;
455 
456 	tx_ring->idx = idx;
457 	tx_ring->r_vec = r_vec;
458 
459 	tx_ring->qcidx = tx_ring->idx * nn->stride_tx;
460 	tx_ring->qcp_q = nn->tx_bar + NFP_QCP_QUEUE_OFF(tx_ring->qcidx);
461 }
462 
463 /**
464  * nfp_net_rx_ring_init() - Fill in the boilerplate for a RX ring
465  * @rx_ring:  RX ring structure
466  * @r_vec:    IRQ vector servicing this ring
467  * @idx:      Ring index
468  */
469 static void
470 nfp_net_rx_ring_init(struct nfp_net_rx_ring *rx_ring,
471 		     struct nfp_net_r_vector *r_vec, unsigned int idx)
472 {
473 	struct nfp_net *nn = r_vec->nfp_net;
474 
475 	rx_ring->idx = idx;
476 	rx_ring->r_vec = r_vec;
477 
478 	rx_ring->fl_qcidx = rx_ring->idx * nn->stride_rx;
479 	rx_ring->rx_qcidx = rx_ring->fl_qcidx + (nn->stride_rx - 1);
480 
481 	rx_ring->qcp_fl = nn->rx_bar + NFP_QCP_QUEUE_OFF(rx_ring->fl_qcidx);
482 	rx_ring->qcp_rx = nn->rx_bar + NFP_QCP_QUEUE_OFF(rx_ring->rx_qcidx);
483 }
484 
485 /**
486  * nfp_net_vecs_init() - Assign IRQs and setup rvecs.
487  * @netdev:   netdev structure
488  */
489 static void nfp_net_vecs_init(struct net_device *netdev)
490 {
491 	struct nfp_net *nn = netdev_priv(netdev);
492 	struct nfp_net_r_vector *r_vec;
493 	int r;
494 
495 	nn->lsc_handler = nfp_net_irq_lsc;
496 	nn->exn_handler = nfp_net_irq_exn;
497 
498 	for (r = 0; r < nn->max_r_vecs; r++) {
499 		struct msix_entry *entry;
500 
501 		entry = &nn->irq_entries[NFP_NET_NON_Q_VECTORS + r];
502 
503 		r_vec = &nn->r_vecs[r];
504 		r_vec->nfp_net = nn;
505 		r_vec->handler = nfp_net_irq_rxtx;
506 		r_vec->irq_entry = entry->entry;
507 		r_vec->irq_vector = entry->vector;
508 
509 		cpumask_set_cpu(r, &r_vec->affinity_mask);
510 	}
511 }
512 
513 /**
514  * nfp_net_aux_irq_request() - Request an auxiliary interrupt (LSC or EXN)
515  * @nn:		NFP Network structure
516  * @ctrl_offset: Control BAR offset where IRQ configuration should be written
517  * @format:	printf-style format to construct the interrupt name
518  * @name:	Pointer to allocated space for interrupt name
519  * @name_sz:	Size of space for interrupt name
520  * @vector_idx:	Index of MSI-X vector used for this interrupt
521  * @handler:	IRQ handler to register for this interrupt
522  */
523 static int
524 nfp_net_aux_irq_request(struct nfp_net *nn, u32 ctrl_offset,
525 			const char *format, char *name, size_t name_sz,
526 			unsigned int vector_idx, irq_handler_t handler)
527 {
528 	struct msix_entry *entry;
529 	int err;
530 
531 	entry = &nn->irq_entries[vector_idx];
532 
533 	snprintf(name, name_sz, format, netdev_name(nn->netdev));
534 	err = request_irq(entry->vector, handler, 0, name, nn);
535 	if (err) {
536 		nn_err(nn, "Failed to request IRQ %d (err=%d).\n",
537 		       entry->vector, err);
538 		return err;
539 	}
540 	nn_writeb(nn, ctrl_offset, entry->entry);
541 
542 	return 0;
543 }
544 
545 /**
546  * nfp_net_aux_irq_free() - Free an auxiliary interrupt (LSC or EXN)
547  * @nn:		NFP Network structure
548  * @ctrl_offset: Control BAR offset where IRQ configuration should be written
549  * @vector_idx:	Index of MSI-X vector used for this interrupt
550  */
551 static void nfp_net_aux_irq_free(struct nfp_net *nn, u32 ctrl_offset,
552 				 unsigned int vector_idx)
553 {
554 	nn_writeb(nn, ctrl_offset, 0xff);
555 	free_irq(nn->irq_entries[vector_idx].vector, nn);
556 }
557 
558 /* Transmit
559  *
560  * One queue controller peripheral queue is used for transmit.  The
561  * driver en-queues packets for transmit by advancing the write
562  * pointer.  The device indicates that packets have transmitted by
563  * advancing the read pointer.  The driver maintains a local copy of
564  * the read and write pointer in @struct nfp_net_tx_ring.  The driver
565  * keeps @wr_p in sync with the queue controller write pointer and can
566  * determine how many packets have been transmitted by comparing its
567  * copy of the read pointer @rd_p with the read pointer maintained by
568  * the queue controller peripheral.
569  */
570 
571 /**
572  * nfp_net_tx_full() - Check if the TX ring is full
573  * @tx_ring: TX ring to check
574  * @dcnt:    Number of descriptors that need to be enqueued (must be >= 1)
575  *
576  * This function checks, based on the *host copy* of read/write
577  * pointer if a given TX ring is full.  The real TX queue may have
578  * some newly made available slots.
579  *
580  * Return: True if the ring is full.
581  */
582 static int nfp_net_tx_full(struct nfp_net_tx_ring *tx_ring, int dcnt)
583 {
584 	return (tx_ring->wr_p - tx_ring->rd_p) >= (tx_ring->cnt - dcnt);
585 }
586 
587 /* Wrappers for deciding when to stop and restart TX queues */
588 static int nfp_net_tx_ring_should_wake(struct nfp_net_tx_ring *tx_ring)
589 {
590 	return !nfp_net_tx_full(tx_ring, MAX_SKB_FRAGS * 4);
591 }
592 
593 static int nfp_net_tx_ring_should_stop(struct nfp_net_tx_ring *tx_ring)
594 {
595 	return nfp_net_tx_full(tx_ring, MAX_SKB_FRAGS + 1);
596 }
597 
598 /**
599  * nfp_net_tx_ring_stop() - stop tx ring
600  * @nd_q:    netdev queue
601  * @tx_ring: driver tx queue structure
602  *
603  * Safely stop TX ring.  Remember that while we are running .start_xmit()
604  * someone else may be cleaning the TX ring completions so we need to be
605  * extra careful here.
606  */
607 static void nfp_net_tx_ring_stop(struct netdev_queue *nd_q,
608 				 struct nfp_net_tx_ring *tx_ring)
609 {
610 	netif_tx_stop_queue(nd_q);
611 
612 	/* We can race with the TX completion out of NAPI so recheck */
613 	smp_mb();
614 	if (unlikely(nfp_net_tx_ring_should_wake(tx_ring)))
615 		netif_tx_start_queue(nd_q);
616 }
617 
618 /**
619  * nfp_net_tx_tso() - Set up Tx descriptor for LSO
620  * @nn:  NFP Net device
621  * @r_vec: per-ring structure
622  * @txbuf: Pointer to driver soft TX descriptor
623  * @txd: Pointer to HW TX descriptor
624  * @skb: Pointer to SKB
625  *
626  * Set up Tx descriptor for LSO, do nothing for non-LSO skbs.
627  * Return error on packet header greater than maximum supported LSO header size.
628  */
629 static void nfp_net_tx_tso(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
630 			   struct nfp_net_tx_buf *txbuf,
631 			   struct nfp_net_tx_desc *txd, struct sk_buff *skb)
632 {
633 	u32 hdrlen;
634 	u16 mss;
635 
636 	if (!skb_is_gso(skb))
637 		return;
638 
639 	if (!skb->encapsulation)
640 		hdrlen = skb_transport_offset(skb) + tcp_hdrlen(skb);
641 	else
642 		hdrlen = skb_inner_transport_header(skb) - skb->data +
643 			inner_tcp_hdrlen(skb);
644 
645 	txbuf->pkt_cnt = skb_shinfo(skb)->gso_segs;
646 	txbuf->real_len += hdrlen * (txbuf->pkt_cnt - 1);
647 
648 	mss = skb_shinfo(skb)->gso_size & PCIE_DESC_TX_MSS_MASK;
649 	txd->l4_offset = hdrlen;
650 	txd->mss = cpu_to_le16(mss);
651 	txd->flags |= PCIE_DESC_TX_LSO;
652 
653 	u64_stats_update_begin(&r_vec->tx_sync);
654 	r_vec->tx_lso++;
655 	u64_stats_update_end(&r_vec->tx_sync);
656 }
657 
658 /**
659  * nfp_net_tx_csum() - Set TX CSUM offload flags in TX descriptor
660  * @nn:  NFP Net device
661  * @r_vec: per-ring structure
662  * @txbuf: Pointer to driver soft TX descriptor
663  * @txd: Pointer to TX descriptor
664  * @skb: Pointer to SKB
665  *
666  * This function sets the TX checksum flags in the TX descriptor based
667  * on the configuration and the protocol of the packet to be transmitted.
668  */
669 static void nfp_net_tx_csum(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
670 			    struct nfp_net_tx_buf *txbuf,
671 			    struct nfp_net_tx_desc *txd, struct sk_buff *skb)
672 {
673 	struct ipv6hdr *ipv6h;
674 	struct iphdr *iph;
675 	u8 l4_hdr;
676 
677 	if (!(nn->ctrl & NFP_NET_CFG_CTRL_TXCSUM))
678 		return;
679 
680 	if (skb->ip_summed != CHECKSUM_PARTIAL)
681 		return;
682 
683 	txd->flags |= PCIE_DESC_TX_CSUM;
684 	if (skb->encapsulation)
685 		txd->flags |= PCIE_DESC_TX_ENCAP;
686 
687 	iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
688 	ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
689 
690 	if (iph->version == 4) {
691 		txd->flags |= PCIE_DESC_TX_IP4_CSUM;
692 		l4_hdr = iph->protocol;
693 	} else if (ipv6h->version == 6) {
694 		l4_hdr = ipv6h->nexthdr;
695 	} else {
696 		nn_warn_ratelimit(nn, "partial checksum but ipv=%x!\n",
697 				  iph->version);
698 		return;
699 	}
700 
701 	switch (l4_hdr) {
702 	case IPPROTO_TCP:
703 		txd->flags |= PCIE_DESC_TX_TCP_CSUM;
704 		break;
705 	case IPPROTO_UDP:
706 		txd->flags |= PCIE_DESC_TX_UDP_CSUM;
707 		break;
708 	default:
709 		nn_warn_ratelimit(nn, "partial checksum but l4 proto=%x!\n",
710 				  l4_hdr);
711 		return;
712 	}
713 
714 	u64_stats_update_begin(&r_vec->tx_sync);
715 	if (skb->encapsulation)
716 		r_vec->hw_csum_tx_inner += txbuf->pkt_cnt;
717 	else
718 		r_vec->hw_csum_tx += txbuf->pkt_cnt;
719 	u64_stats_update_end(&r_vec->tx_sync);
720 }
721 
722 static void nfp_net_tx_xmit_more_flush(struct nfp_net_tx_ring *tx_ring)
723 {
724 	wmb();
725 	nfp_qcp_wr_ptr_add(tx_ring->qcp_q, tx_ring->wr_ptr_add);
726 	tx_ring->wr_ptr_add = 0;
727 }
728 
729 /**
730  * nfp_net_tx() - Main transmit entry point
731  * @skb:    SKB to transmit
732  * @netdev: netdev structure
733  *
734  * Return: NETDEV_TX_OK on success.
735  */
736 static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
737 {
738 	struct nfp_net *nn = netdev_priv(netdev);
739 	const struct skb_frag_struct *frag;
740 	struct nfp_net_r_vector *r_vec;
741 	struct nfp_net_tx_desc *txd, txdg;
742 	struct nfp_net_tx_buf *txbuf;
743 	struct nfp_net_tx_ring *tx_ring;
744 	struct netdev_queue *nd_q;
745 	dma_addr_t dma_addr;
746 	unsigned int fsize;
747 	int f, nr_frags;
748 	int wr_idx;
749 	u16 qidx;
750 
751 	qidx = skb_get_queue_mapping(skb);
752 	tx_ring = &nn->tx_rings[qidx];
753 	r_vec = tx_ring->r_vec;
754 	nd_q = netdev_get_tx_queue(nn->netdev, qidx);
755 
756 	nr_frags = skb_shinfo(skb)->nr_frags;
757 
758 	if (unlikely(nfp_net_tx_full(tx_ring, nr_frags + 1))) {
759 		nn_warn_ratelimit(nn, "TX ring %d busy. wrp=%u rdp=%u\n",
760 				  qidx, tx_ring->wr_p, tx_ring->rd_p);
761 		netif_tx_stop_queue(nd_q);
762 		u64_stats_update_begin(&r_vec->tx_sync);
763 		r_vec->tx_busy++;
764 		u64_stats_update_end(&r_vec->tx_sync);
765 		return NETDEV_TX_BUSY;
766 	}
767 
768 	/* Start with the head skbuf */
769 	dma_addr = dma_map_single(&nn->pdev->dev, skb->data, skb_headlen(skb),
770 				  DMA_TO_DEVICE);
771 	if (dma_mapping_error(&nn->pdev->dev, dma_addr))
772 		goto err_free;
773 
774 	wr_idx = tx_ring->wr_p & (tx_ring->cnt - 1);
775 
776 	/* Stash the soft descriptor of the head then initialize it */
777 	txbuf = &tx_ring->txbufs[wr_idx];
778 	txbuf->skb = skb;
779 	txbuf->dma_addr = dma_addr;
780 	txbuf->fidx = -1;
781 	txbuf->pkt_cnt = 1;
782 	txbuf->real_len = skb->len;
783 
784 	/* Build TX descriptor */
785 	txd = &tx_ring->txds[wr_idx];
786 	txd->offset_eop = (nr_frags == 0) ? PCIE_DESC_TX_EOP : 0;
787 	txd->dma_len = cpu_to_le16(skb_headlen(skb));
788 	nfp_desc_set_dma_addr(txd, dma_addr);
789 	txd->data_len = cpu_to_le16(skb->len);
790 
791 	txd->flags = 0;
792 	txd->mss = 0;
793 	txd->l4_offset = 0;
794 
795 	nfp_net_tx_tso(nn, r_vec, txbuf, txd, skb);
796 
797 	nfp_net_tx_csum(nn, r_vec, txbuf, txd, skb);
798 
799 	if (skb_vlan_tag_present(skb) && nn->ctrl & NFP_NET_CFG_CTRL_TXVLAN) {
800 		txd->flags |= PCIE_DESC_TX_VLAN;
801 		txd->vlan = cpu_to_le16(skb_vlan_tag_get(skb));
802 	}
803 
804 	/* Gather DMA */
805 	if (nr_frags > 0) {
806 		/* all descs must match except for in addr, length and eop */
807 		txdg = *txd;
808 
809 		for (f = 0; f < nr_frags; f++) {
810 			frag = &skb_shinfo(skb)->frags[f];
811 			fsize = skb_frag_size(frag);
812 
813 			dma_addr = skb_frag_dma_map(&nn->pdev->dev, frag, 0,
814 						    fsize, DMA_TO_DEVICE);
815 			if (dma_mapping_error(&nn->pdev->dev, dma_addr))
816 				goto err_unmap;
817 
818 			wr_idx = (wr_idx + 1) & (tx_ring->cnt - 1);
819 			tx_ring->txbufs[wr_idx].skb = skb;
820 			tx_ring->txbufs[wr_idx].dma_addr = dma_addr;
821 			tx_ring->txbufs[wr_idx].fidx = f;
822 
823 			txd = &tx_ring->txds[wr_idx];
824 			*txd = txdg;
825 			txd->dma_len = cpu_to_le16(fsize);
826 			nfp_desc_set_dma_addr(txd, dma_addr);
827 			txd->offset_eop =
828 				(f == nr_frags - 1) ? PCIE_DESC_TX_EOP : 0;
829 		}
830 
831 		u64_stats_update_begin(&r_vec->tx_sync);
832 		r_vec->tx_gather++;
833 		u64_stats_update_end(&r_vec->tx_sync);
834 	}
835 
836 	netdev_tx_sent_queue(nd_q, txbuf->real_len);
837 
838 	tx_ring->wr_p += nr_frags + 1;
839 	if (nfp_net_tx_ring_should_stop(tx_ring))
840 		nfp_net_tx_ring_stop(nd_q, tx_ring);
841 
842 	tx_ring->wr_ptr_add += nr_frags + 1;
843 	if (!skb->xmit_more || netif_xmit_stopped(nd_q))
844 		nfp_net_tx_xmit_more_flush(tx_ring);
845 
846 	skb_tx_timestamp(skb);
847 
848 	return NETDEV_TX_OK;
849 
850 err_unmap:
851 	--f;
852 	while (f >= 0) {
853 		frag = &skb_shinfo(skb)->frags[f];
854 		dma_unmap_page(&nn->pdev->dev,
855 			       tx_ring->txbufs[wr_idx].dma_addr,
856 			       skb_frag_size(frag), DMA_TO_DEVICE);
857 		tx_ring->txbufs[wr_idx].skb = NULL;
858 		tx_ring->txbufs[wr_idx].dma_addr = 0;
859 		tx_ring->txbufs[wr_idx].fidx = -2;
860 		wr_idx = wr_idx - 1;
861 		if (wr_idx < 0)
862 			wr_idx += tx_ring->cnt;
863 	}
864 	dma_unmap_single(&nn->pdev->dev, tx_ring->txbufs[wr_idx].dma_addr,
865 			 skb_headlen(skb), DMA_TO_DEVICE);
866 	tx_ring->txbufs[wr_idx].skb = NULL;
867 	tx_ring->txbufs[wr_idx].dma_addr = 0;
868 	tx_ring->txbufs[wr_idx].fidx = -2;
869 err_free:
870 	nn_warn_ratelimit(nn, "Failed to map DMA TX buffer\n");
871 	u64_stats_update_begin(&r_vec->tx_sync);
872 	r_vec->tx_errors++;
873 	u64_stats_update_end(&r_vec->tx_sync);
874 	dev_kfree_skb_any(skb);
875 	return NETDEV_TX_OK;
876 }
877 
878 /**
879  * nfp_net_tx_complete() - Handled completed TX packets
880  * @tx_ring:   TX ring structure
881  *
882  * Return: Number of completed TX descriptors
883  */
884 static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring)
885 {
886 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
887 	struct nfp_net *nn = r_vec->nfp_net;
888 	const struct skb_frag_struct *frag;
889 	struct netdev_queue *nd_q;
890 	u32 done_pkts = 0, done_bytes = 0;
891 	struct sk_buff *skb;
892 	int todo, nr_frags;
893 	u32 qcp_rd_p;
894 	int fidx;
895 	int idx;
896 
897 	/* Work out how many descriptors have been transmitted */
898 	qcp_rd_p = nfp_qcp_rd_ptr_read(tx_ring->qcp_q);
899 
900 	if (qcp_rd_p == tx_ring->qcp_rd_p)
901 		return;
902 
903 	if (qcp_rd_p > tx_ring->qcp_rd_p)
904 		todo = qcp_rd_p - tx_ring->qcp_rd_p;
905 	else
906 		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
907 
908 	while (todo--) {
909 		idx = tx_ring->rd_p & (tx_ring->cnt - 1);
910 		tx_ring->rd_p++;
911 
912 		skb = tx_ring->txbufs[idx].skb;
913 		if (!skb)
914 			continue;
915 
916 		nr_frags = skb_shinfo(skb)->nr_frags;
917 		fidx = tx_ring->txbufs[idx].fidx;
918 
919 		if (fidx == -1) {
920 			/* unmap head */
921 			dma_unmap_single(&nn->pdev->dev,
922 					 tx_ring->txbufs[idx].dma_addr,
923 					 skb_headlen(skb), DMA_TO_DEVICE);
924 
925 			done_pkts += tx_ring->txbufs[idx].pkt_cnt;
926 			done_bytes += tx_ring->txbufs[idx].real_len;
927 		} else {
928 			/* unmap fragment */
929 			frag = &skb_shinfo(skb)->frags[fidx];
930 			dma_unmap_page(&nn->pdev->dev,
931 				       tx_ring->txbufs[idx].dma_addr,
932 				       skb_frag_size(frag), DMA_TO_DEVICE);
933 		}
934 
935 		/* check for last gather fragment */
936 		if (fidx == nr_frags - 1)
937 			dev_kfree_skb_any(skb);
938 
939 		tx_ring->txbufs[idx].dma_addr = 0;
940 		tx_ring->txbufs[idx].skb = NULL;
941 		tx_ring->txbufs[idx].fidx = -2;
942 	}
943 
944 	tx_ring->qcp_rd_p = qcp_rd_p;
945 
946 	u64_stats_update_begin(&r_vec->tx_sync);
947 	r_vec->tx_bytes += done_bytes;
948 	r_vec->tx_pkts += done_pkts;
949 	u64_stats_update_end(&r_vec->tx_sync);
950 
951 	nd_q = netdev_get_tx_queue(nn->netdev, tx_ring->idx);
952 	netdev_tx_completed_queue(nd_q, done_pkts, done_bytes);
953 	if (nfp_net_tx_ring_should_wake(tx_ring)) {
954 		/* Make sure TX thread will see updated tx_ring->rd_p */
955 		smp_mb();
956 
957 		if (unlikely(netif_tx_queue_stopped(nd_q)))
958 			netif_tx_wake_queue(nd_q);
959 	}
960 
961 	WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
962 		  "TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
963 		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
964 }
965 
966 static void nfp_net_xdp_complete(struct nfp_net_tx_ring *tx_ring)
967 {
968 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
969 	struct nfp_net *nn = r_vec->nfp_net;
970 	u32 done_pkts = 0, done_bytes = 0;
971 	int idx, todo;
972 	u32 qcp_rd_p;
973 
974 	/* Work out how many descriptors have been transmitted */
975 	qcp_rd_p = nfp_qcp_rd_ptr_read(tx_ring->qcp_q);
976 
977 	if (qcp_rd_p == tx_ring->qcp_rd_p)
978 		return;
979 
980 	if (qcp_rd_p > tx_ring->qcp_rd_p)
981 		todo = qcp_rd_p - tx_ring->qcp_rd_p;
982 	else
983 		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
984 
985 	while (todo--) {
986 		idx = tx_ring->rd_p & (tx_ring->cnt - 1);
987 		tx_ring->rd_p++;
988 
989 		if (!tx_ring->txbufs[idx].frag)
990 			continue;
991 
992 		nfp_net_dma_unmap_rx(nn, tx_ring->txbufs[idx].dma_addr,
993 				     nn->fl_bufsz, DMA_BIDIRECTIONAL);
994 		__free_page(virt_to_page(tx_ring->txbufs[idx].frag));
995 
996 		done_pkts++;
997 		done_bytes += tx_ring->txbufs[idx].real_len;
998 
999 		tx_ring->txbufs[idx].dma_addr = 0;
1000 		tx_ring->txbufs[idx].frag = NULL;
1001 		tx_ring->txbufs[idx].fidx = -2;
1002 	}
1003 
1004 	tx_ring->qcp_rd_p = qcp_rd_p;
1005 
1006 	u64_stats_update_begin(&r_vec->tx_sync);
1007 	r_vec->tx_bytes += done_bytes;
1008 	r_vec->tx_pkts += done_pkts;
1009 	u64_stats_update_end(&r_vec->tx_sync);
1010 
1011 	WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
1012 		  "TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
1013 		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
1014 }
1015 
1016 /**
1017  * nfp_net_tx_ring_reset() - Free any untransmitted buffers and reset pointers
1018  * @nn:		NFP Net device
1019  * @tx_ring:	TX ring structure
1020  *
1021  * Assumes that the device is stopped
1022  */
1023 static void
1024 nfp_net_tx_ring_reset(struct nfp_net *nn, struct nfp_net_tx_ring *tx_ring)
1025 {
1026 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
1027 	const struct skb_frag_struct *frag;
1028 	struct pci_dev *pdev = nn->pdev;
1029 	struct netdev_queue *nd_q;
1030 
1031 	while (tx_ring->rd_p != tx_ring->wr_p) {
1032 		struct nfp_net_tx_buf *tx_buf;
1033 		int idx;
1034 
1035 		idx = tx_ring->rd_p & (tx_ring->cnt - 1);
1036 		tx_buf = &tx_ring->txbufs[idx];
1037 
1038 		if (tx_ring == r_vec->xdp_ring) {
1039 			nfp_net_dma_unmap_rx(nn, tx_buf->dma_addr,
1040 					     nn->fl_bufsz, DMA_BIDIRECTIONAL);
1041 			__free_page(virt_to_page(tx_ring->txbufs[idx].frag));
1042 		} else {
1043 			struct sk_buff *skb = tx_ring->txbufs[idx].skb;
1044 			int nr_frags = skb_shinfo(skb)->nr_frags;
1045 
1046 			if (tx_buf->fidx == -1) {
1047 				/* unmap head */
1048 				dma_unmap_single(&pdev->dev, tx_buf->dma_addr,
1049 						 skb_headlen(skb),
1050 						 DMA_TO_DEVICE);
1051 			} else {
1052 				/* unmap fragment */
1053 				frag = &skb_shinfo(skb)->frags[tx_buf->fidx];
1054 				dma_unmap_page(&pdev->dev, tx_buf->dma_addr,
1055 					       skb_frag_size(frag),
1056 					       DMA_TO_DEVICE);
1057 			}
1058 
1059 			/* check for last gather fragment */
1060 			if (tx_buf->fidx == nr_frags - 1)
1061 				dev_kfree_skb_any(skb);
1062 		}
1063 
1064 		tx_buf->dma_addr = 0;
1065 		tx_buf->skb = NULL;
1066 		tx_buf->fidx = -2;
1067 
1068 		tx_ring->qcp_rd_p++;
1069 		tx_ring->rd_p++;
1070 	}
1071 
1072 	memset(tx_ring->txds, 0, sizeof(*tx_ring->txds) * tx_ring->cnt);
1073 	tx_ring->wr_p = 0;
1074 	tx_ring->rd_p = 0;
1075 	tx_ring->qcp_rd_p = 0;
1076 	tx_ring->wr_ptr_add = 0;
1077 
1078 	if (tx_ring == r_vec->xdp_ring)
1079 		return;
1080 
1081 	nd_q = netdev_get_tx_queue(nn->netdev, tx_ring->idx);
1082 	netdev_tx_reset_queue(nd_q);
1083 }
1084 
1085 static void nfp_net_tx_timeout(struct net_device *netdev)
1086 {
1087 	struct nfp_net *nn = netdev_priv(netdev);
1088 	int i;
1089 
1090 	for (i = 0; i < nn->netdev->real_num_tx_queues; i++) {
1091 		if (!netif_tx_queue_stopped(netdev_get_tx_queue(netdev, i)))
1092 			continue;
1093 		nn_warn(nn, "TX timeout on ring: %d\n", i);
1094 	}
1095 	nn_warn(nn, "TX watchdog timeout\n");
1096 }
1097 
1098 /* Receive processing
1099  */
1100 static unsigned int
1101 nfp_net_calc_fl_bufsz(struct nfp_net *nn, unsigned int mtu)
1102 {
1103 	unsigned int fl_bufsz;
1104 
1105 	fl_bufsz = NFP_NET_RX_BUF_HEADROOM;
1106 	if (nn->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
1107 		fl_bufsz += NFP_NET_MAX_PREPEND;
1108 	else
1109 		fl_bufsz += nn->rx_offset;
1110 	fl_bufsz += ETH_HLEN + VLAN_HLEN * 2 + mtu;
1111 
1112 	fl_bufsz = SKB_DATA_ALIGN(fl_bufsz);
1113 	fl_bufsz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
1114 
1115 	return fl_bufsz;
1116 }
1117 
1118 static void
1119 nfp_net_free_frag(void *frag, bool xdp)
1120 {
1121 	if (!xdp)
1122 		skb_free_frag(frag);
1123 	else
1124 		__free_page(virt_to_page(frag));
1125 }
1126 
1127 /**
1128  * nfp_net_rx_alloc_one() - Allocate and map page frag for RX
1129  * @rx_ring:	RX ring structure of the skb
1130  * @dma_addr:	Pointer to storage for DMA address (output param)
1131  * @fl_bufsz:	size of freelist buffers
1132  * @xdp:	Whether XDP is enabled
1133  *
1134  * This function will allcate a new page frag, map it for DMA.
1135  *
1136  * Return: allocated page frag or NULL on failure.
1137  */
1138 static void *
1139 nfp_net_rx_alloc_one(struct nfp_net_rx_ring *rx_ring, dma_addr_t *dma_addr,
1140 		     unsigned int fl_bufsz, bool xdp)
1141 {
1142 	struct nfp_net *nn = rx_ring->r_vec->nfp_net;
1143 	int direction;
1144 	void *frag;
1145 
1146 	if (!xdp)
1147 		frag = netdev_alloc_frag(fl_bufsz);
1148 	else
1149 		frag = page_address(alloc_page(GFP_KERNEL | __GFP_COLD));
1150 	if (!frag) {
1151 		nn_warn_ratelimit(nn, "Failed to alloc receive page frag\n");
1152 		return NULL;
1153 	}
1154 
1155 	direction = xdp ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
1156 
1157 	*dma_addr = nfp_net_dma_map_rx(nn, frag, fl_bufsz, direction);
1158 	if (dma_mapping_error(&nn->pdev->dev, *dma_addr)) {
1159 		nfp_net_free_frag(frag, xdp);
1160 		nn_warn_ratelimit(nn, "Failed to map DMA RX buffer\n");
1161 		return NULL;
1162 	}
1163 
1164 	return frag;
1165 }
1166 
1167 static void *
1168 nfp_net_napi_alloc_one(struct nfp_net *nn, int direction, dma_addr_t *dma_addr)
1169 {
1170 	void *frag;
1171 
1172 	if (!nn->xdp_prog)
1173 		frag = napi_alloc_frag(nn->fl_bufsz);
1174 	else
1175 		frag = page_address(alloc_page(GFP_ATOMIC | __GFP_COLD));
1176 	if (!frag) {
1177 		nn_warn_ratelimit(nn, "Failed to alloc receive page frag\n");
1178 		return NULL;
1179 	}
1180 
1181 	*dma_addr = nfp_net_dma_map_rx(nn, frag, nn->fl_bufsz, direction);
1182 	if (dma_mapping_error(&nn->pdev->dev, *dma_addr)) {
1183 		nfp_net_free_frag(frag, nn->xdp_prog);
1184 		nn_warn_ratelimit(nn, "Failed to map DMA RX buffer\n");
1185 		return NULL;
1186 	}
1187 
1188 	return frag;
1189 }
1190 
1191 /**
1192  * nfp_net_rx_give_one() - Put mapped skb on the software and hardware rings
1193  * @rx_ring:	RX ring structure
1194  * @frag:	page fragment buffer
1195  * @dma_addr:	DMA address of skb mapping
1196  */
1197 static void nfp_net_rx_give_one(struct nfp_net_rx_ring *rx_ring,
1198 				void *frag, dma_addr_t dma_addr)
1199 {
1200 	unsigned int wr_idx;
1201 
1202 	wr_idx = rx_ring->wr_p & (rx_ring->cnt - 1);
1203 
1204 	/* Stash SKB and DMA address away */
1205 	rx_ring->rxbufs[wr_idx].frag = frag;
1206 	rx_ring->rxbufs[wr_idx].dma_addr = dma_addr;
1207 
1208 	/* Fill freelist descriptor */
1209 	rx_ring->rxds[wr_idx].fld.reserved = 0;
1210 	rx_ring->rxds[wr_idx].fld.meta_len_dd = 0;
1211 	nfp_desc_set_dma_addr(&rx_ring->rxds[wr_idx].fld, dma_addr);
1212 
1213 	rx_ring->wr_p++;
1214 	rx_ring->wr_ptr_add++;
1215 	if (rx_ring->wr_ptr_add >= NFP_NET_FL_BATCH) {
1216 		/* Update write pointer of the freelist queue. Make
1217 		 * sure all writes are flushed before telling the hardware.
1218 		 */
1219 		wmb();
1220 		nfp_qcp_wr_ptr_add(rx_ring->qcp_fl, rx_ring->wr_ptr_add);
1221 		rx_ring->wr_ptr_add = 0;
1222 	}
1223 }
1224 
1225 /**
1226  * nfp_net_rx_ring_reset() - Reflect in SW state of freelist after disable
1227  * @rx_ring:	RX ring structure
1228  *
1229  * Warning: Do *not* call if ring buffers were never put on the FW freelist
1230  *	    (i.e. device was not enabled)!
1231  */
1232 static void nfp_net_rx_ring_reset(struct nfp_net_rx_ring *rx_ring)
1233 {
1234 	unsigned int wr_idx, last_idx;
1235 
1236 	/* Move the empty entry to the end of the list */
1237 	wr_idx = rx_ring->wr_p & (rx_ring->cnt - 1);
1238 	last_idx = rx_ring->cnt - 1;
1239 	rx_ring->rxbufs[wr_idx].dma_addr = rx_ring->rxbufs[last_idx].dma_addr;
1240 	rx_ring->rxbufs[wr_idx].frag = rx_ring->rxbufs[last_idx].frag;
1241 	rx_ring->rxbufs[last_idx].dma_addr = 0;
1242 	rx_ring->rxbufs[last_idx].frag = NULL;
1243 
1244 	memset(rx_ring->rxds, 0, sizeof(*rx_ring->rxds) * rx_ring->cnt);
1245 	rx_ring->wr_p = 0;
1246 	rx_ring->rd_p = 0;
1247 	rx_ring->wr_ptr_add = 0;
1248 }
1249 
1250 /**
1251  * nfp_net_rx_ring_bufs_free() - Free any buffers currently on the RX ring
1252  * @nn:		NFP Net device
1253  * @rx_ring:	RX ring to remove buffers from
1254  * @xdp:	Whether XDP is enabled
1255  *
1256  * Assumes that the device is stopped and buffers are in [0, ring->cnt - 1)
1257  * entries.  After device is disabled nfp_net_rx_ring_reset() must be called
1258  * to restore required ring geometry.
1259  */
1260 static void
1261 nfp_net_rx_ring_bufs_free(struct nfp_net *nn, struct nfp_net_rx_ring *rx_ring,
1262 			  bool xdp)
1263 {
1264 	int direction = xdp ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
1265 	unsigned int i;
1266 
1267 	for (i = 0; i < rx_ring->cnt - 1; i++) {
1268 		/* NULL skb can only happen when initial filling of the ring
1269 		 * fails to allocate enough buffers and calls here to free
1270 		 * already allocated ones.
1271 		 */
1272 		if (!rx_ring->rxbufs[i].frag)
1273 			continue;
1274 
1275 		nfp_net_dma_unmap_rx(nn, rx_ring->rxbufs[i].dma_addr,
1276 				     rx_ring->bufsz, direction);
1277 		nfp_net_free_frag(rx_ring->rxbufs[i].frag, xdp);
1278 		rx_ring->rxbufs[i].dma_addr = 0;
1279 		rx_ring->rxbufs[i].frag = NULL;
1280 	}
1281 }
1282 
1283 /**
1284  * nfp_net_rx_ring_bufs_alloc() - Fill RX ring with buffers (don't give to FW)
1285  * @nn:		NFP Net device
1286  * @rx_ring:	RX ring to remove buffers from
1287  * @xdp:	Whether XDP is enabled
1288  */
1289 static int
1290 nfp_net_rx_ring_bufs_alloc(struct nfp_net *nn, struct nfp_net_rx_ring *rx_ring,
1291 			   bool xdp)
1292 {
1293 	struct nfp_net_rx_buf *rxbufs;
1294 	unsigned int i;
1295 
1296 	rxbufs = rx_ring->rxbufs;
1297 
1298 	for (i = 0; i < rx_ring->cnt - 1; i++) {
1299 		rxbufs[i].frag =
1300 			nfp_net_rx_alloc_one(rx_ring, &rxbufs[i].dma_addr,
1301 					     rx_ring->bufsz, xdp);
1302 		if (!rxbufs[i].frag) {
1303 			nfp_net_rx_ring_bufs_free(nn, rx_ring, xdp);
1304 			return -ENOMEM;
1305 		}
1306 	}
1307 
1308 	return 0;
1309 }
1310 
1311 /**
1312  * nfp_net_rx_ring_fill_freelist() - Give buffers from the ring to FW
1313  * @rx_ring: RX ring to fill
1314  */
1315 static void nfp_net_rx_ring_fill_freelist(struct nfp_net_rx_ring *rx_ring)
1316 {
1317 	unsigned int i;
1318 
1319 	for (i = 0; i < rx_ring->cnt - 1; i++)
1320 		nfp_net_rx_give_one(rx_ring, rx_ring->rxbufs[i].frag,
1321 				    rx_ring->rxbufs[i].dma_addr);
1322 }
1323 
1324 /**
1325  * nfp_net_rx_csum_has_errors() - group check if rxd has any csum errors
1326  * @flags: RX descriptor flags field in CPU byte order
1327  */
1328 static int nfp_net_rx_csum_has_errors(u16 flags)
1329 {
1330 	u16 csum_all_checked, csum_all_ok;
1331 
1332 	csum_all_checked = flags & __PCIE_DESC_RX_CSUM_ALL;
1333 	csum_all_ok = flags & __PCIE_DESC_RX_CSUM_ALL_OK;
1334 
1335 	return csum_all_checked != (csum_all_ok << PCIE_DESC_RX_CSUM_OK_SHIFT);
1336 }
1337 
1338 /**
1339  * nfp_net_rx_csum() - set SKB checksum field based on RX descriptor flags
1340  * @nn:  NFP Net device
1341  * @r_vec: per-ring structure
1342  * @rxd: Pointer to RX descriptor
1343  * @skb: Pointer to SKB
1344  */
1345 static void nfp_net_rx_csum(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
1346 			    struct nfp_net_rx_desc *rxd, struct sk_buff *skb)
1347 {
1348 	skb_checksum_none_assert(skb);
1349 
1350 	if (!(nn->netdev->features & NETIF_F_RXCSUM))
1351 		return;
1352 
1353 	if (nfp_net_rx_csum_has_errors(le16_to_cpu(rxd->rxd.flags))) {
1354 		u64_stats_update_begin(&r_vec->rx_sync);
1355 		r_vec->hw_csum_rx_error++;
1356 		u64_stats_update_end(&r_vec->rx_sync);
1357 		return;
1358 	}
1359 
1360 	/* Assume that the firmware will never report inner CSUM_OK unless outer
1361 	 * L4 headers were successfully parsed. FW will always report zero UDP
1362 	 * checksum as CSUM_OK.
1363 	 */
1364 	if (rxd->rxd.flags & PCIE_DESC_RX_TCP_CSUM_OK ||
1365 	    rxd->rxd.flags & PCIE_DESC_RX_UDP_CSUM_OK) {
1366 		__skb_incr_checksum_unnecessary(skb);
1367 		u64_stats_update_begin(&r_vec->rx_sync);
1368 		r_vec->hw_csum_rx_ok++;
1369 		u64_stats_update_end(&r_vec->rx_sync);
1370 	}
1371 
1372 	if (rxd->rxd.flags & PCIE_DESC_RX_I_TCP_CSUM_OK ||
1373 	    rxd->rxd.flags & PCIE_DESC_RX_I_UDP_CSUM_OK) {
1374 		__skb_incr_checksum_unnecessary(skb);
1375 		u64_stats_update_begin(&r_vec->rx_sync);
1376 		r_vec->hw_csum_rx_inner_ok++;
1377 		u64_stats_update_end(&r_vec->rx_sync);
1378 	}
1379 }
1380 
1381 static void nfp_net_set_hash(struct net_device *netdev, struct sk_buff *skb,
1382 			     unsigned int type, __be32 *hash)
1383 {
1384 	if (!(netdev->features & NETIF_F_RXHASH))
1385 		return;
1386 
1387 	switch (type) {
1388 	case NFP_NET_RSS_IPV4:
1389 	case NFP_NET_RSS_IPV6:
1390 	case NFP_NET_RSS_IPV6_EX:
1391 		skb_set_hash(skb, get_unaligned_be32(hash), PKT_HASH_TYPE_L3);
1392 		break;
1393 	default:
1394 		skb_set_hash(skb, get_unaligned_be32(hash), PKT_HASH_TYPE_L4);
1395 		break;
1396 	}
1397 }
1398 
1399 static void
1400 nfp_net_set_hash_desc(struct net_device *netdev, struct sk_buff *skb,
1401 		      struct nfp_net_rx_desc *rxd)
1402 {
1403 	struct nfp_net_rx_hash *rx_hash;
1404 
1405 	if (!(rxd->rxd.flags & PCIE_DESC_RX_RSS))
1406 		return;
1407 
1408 	rx_hash = (struct nfp_net_rx_hash *)(skb->data - sizeof(*rx_hash));
1409 
1410 	nfp_net_set_hash(netdev, skb, get_unaligned_be32(&rx_hash->hash_type),
1411 			 &rx_hash->hash);
1412 }
1413 
1414 static void *
1415 nfp_net_parse_meta(struct net_device *netdev, struct sk_buff *skb,
1416 		   int meta_len)
1417 {
1418 	u8 *data = skb->data - meta_len;
1419 	u32 meta_info;
1420 
1421 	meta_info = get_unaligned_be32(data);
1422 	data += 4;
1423 
1424 	while (meta_info) {
1425 		switch (meta_info & NFP_NET_META_FIELD_MASK) {
1426 		case NFP_NET_META_HASH:
1427 			meta_info >>= NFP_NET_META_FIELD_SIZE;
1428 			nfp_net_set_hash(netdev, skb,
1429 					 meta_info & NFP_NET_META_FIELD_MASK,
1430 					 (__be32 *)data);
1431 			data += 4;
1432 			break;
1433 		case NFP_NET_META_MARK:
1434 			skb->mark = get_unaligned_be32(data);
1435 			data += 4;
1436 			break;
1437 		default:
1438 			return NULL;
1439 		}
1440 
1441 		meta_info >>= NFP_NET_META_FIELD_SIZE;
1442 	}
1443 
1444 	return data;
1445 }
1446 
1447 static void
1448 nfp_net_rx_drop(struct nfp_net_r_vector *r_vec, struct nfp_net_rx_ring *rx_ring,
1449 		struct nfp_net_rx_buf *rxbuf, struct sk_buff *skb)
1450 {
1451 	u64_stats_update_begin(&r_vec->rx_sync);
1452 	r_vec->rx_drops++;
1453 	u64_stats_update_end(&r_vec->rx_sync);
1454 
1455 	/* skb is build based on the frag, free_skb() would free the frag
1456 	 * so to be able to reuse it we need an extra ref.
1457 	 */
1458 	if (skb && rxbuf && skb->head == rxbuf->frag)
1459 		page_ref_inc(virt_to_head_page(rxbuf->frag));
1460 	if (rxbuf)
1461 		nfp_net_rx_give_one(rx_ring, rxbuf->frag, rxbuf->dma_addr);
1462 	if (skb)
1463 		dev_kfree_skb_any(skb);
1464 }
1465 
1466 static bool
1467 nfp_net_tx_xdp_buf(struct nfp_net *nn, struct nfp_net_rx_ring *rx_ring,
1468 		   struct nfp_net_tx_ring *tx_ring,
1469 		   struct nfp_net_rx_buf *rxbuf, unsigned int pkt_off,
1470 		   unsigned int pkt_len)
1471 {
1472 	struct nfp_net_tx_buf *txbuf;
1473 	struct nfp_net_tx_desc *txd;
1474 	dma_addr_t new_dma_addr;
1475 	void *new_frag;
1476 	int wr_idx;
1477 
1478 	if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
1479 		nfp_net_rx_drop(rx_ring->r_vec, rx_ring, rxbuf, NULL);
1480 		return false;
1481 	}
1482 
1483 	new_frag = nfp_net_napi_alloc_one(nn, DMA_BIDIRECTIONAL, &new_dma_addr);
1484 	if (unlikely(!new_frag)) {
1485 		nfp_net_rx_drop(rx_ring->r_vec, rx_ring, rxbuf, NULL);
1486 		return false;
1487 	}
1488 	nfp_net_rx_give_one(rx_ring, new_frag, new_dma_addr);
1489 
1490 	wr_idx = tx_ring->wr_p & (tx_ring->cnt - 1);
1491 
1492 	/* Stash the soft descriptor of the head then initialize it */
1493 	txbuf = &tx_ring->txbufs[wr_idx];
1494 	txbuf->frag = rxbuf->frag;
1495 	txbuf->dma_addr = rxbuf->dma_addr;
1496 	txbuf->fidx = -1;
1497 	txbuf->pkt_cnt = 1;
1498 	txbuf->real_len = pkt_len;
1499 
1500 	dma_sync_single_for_device(&nn->pdev->dev, rxbuf->dma_addr + pkt_off,
1501 				   pkt_len, DMA_TO_DEVICE);
1502 
1503 	/* Build TX descriptor */
1504 	txd = &tx_ring->txds[wr_idx];
1505 	txd->offset_eop = PCIE_DESC_TX_EOP;
1506 	txd->dma_len = cpu_to_le16(pkt_len);
1507 	nfp_desc_set_dma_addr(txd, rxbuf->dma_addr + pkt_off);
1508 	txd->data_len = cpu_to_le16(pkt_len);
1509 
1510 	txd->flags = 0;
1511 	txd->mss = 0;
1512 	txd->l4_offset = 0;
1513 
1514 	tx_ring->wr_p++;
1515 	tx_ring->wr_ptr_add++;
1516 	return true;
1517 }
1518 
1519 static int nfp_net_run_xdp(struct bpf_prog *prog, void *data, unsigned int len)
1520 {
1521 	struct xdp_buff xdp;
1522 
1523 	xdp.data = data;
1524 	xdp.data_end = data + len;
1525 
1526 	return bpf_prog_run_xdp(prog, &xdp);
1527 }
1528 
1529 /**
1530  * nfp_net_rx() - receive up to @budget packets on @rx_ring
1531  * @rx_ring:   RX ring to receive from
1532  * @budget:    NAPI budget
1533  *
1534  * Note, this function is separated out from the napi poll function to
1535  * more cleanly separate packet receive code from other bookkeeping
1536  * functions performed in the napi poll function.
1537  *
1538  * Return: Number of packets received.
1539  */
1540 static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
1541 {
1542 	struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
1543 	struct nfp_net *nn = r_vec->nfp_net;
1544 	struct nfp_net_tx_ring *tx_ring;
1545 	struct bpf_prog *xdp_prog;
1546 	unsigned int true_bufsz;
1547 	struct sk_buff *skb;
1548 	int pkts_polled = 0;
1549 	int rx_dma_map_dir;
1550 	int idx;
1551 
1552 	rcu_read_lock();
1553 	xdp_prog = READ_ONCE(nn->xdp_prog);
1554 	rx_dma_map_dir = xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
1555 	true_bufsz = xdp_prog ? PAGE_SIZE : nn->fl_bufsz;
1556 	tx_ring = r_vec->xdp_ring;
1557 
1558 	while (pkts_polled < budget) {
1559 		unsigned int meta_len, data_len, data_off, pkt_len, pkt_off;
1560 		struct nfp_net_rx_buf *rxbuf;
1561 		struct nfp_net_rx_desc *rxd;
1562 		dma_addr_t new_dma_addr;
1563 		void *new_frag;
1564 
1565 		idx = rx_ring->rd_p & (rx_ring->cnt - 1);
1566 
1567 		rxd = &rx_ring->rxds[idx];
1568 		if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
1569 			break;
1570 
1571 		/* Memory barrier to ensure that we won't do other reads
1572 		 * before the DD bit.
1573 		 */
1574 		dma_rmb();
1575 
1576 		rx_ring->rd_p++;
1577 		pkts_polled++;
1578 
1579 		rxbuf =	&rx_ring->rxbufs[idx];
1580 		/*         < meta_len >
1581 		 *  <-- [rx_offset] -->
1582 		 *  ---------------------------------------------------------
1583 		 * | [XX] |  metadata  |             packet           | XXXX |
1584 		 *  ---------------------------------------------------------
1585 		 *         <---------------- data_len --------------->
1586 		 *
1587 		 * The rx_offset is fixed for all packets, the meta_len can vary
1588 		 * on a packet by packet basis. If rx_offset is set to zero
1589 		 * (_RX_OFFSET_DYNAMIC) metadata starts at the beginning of the
1590 		 * buffer and is immediately followed by the packet (no [XX]).
1591 		 */
1592 		meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
1593 		data_len = le16_to_cpu(rxd->rxd.data_len);
1594 		pkt_len = data_len - meta_len;
1595 
1596 		if (nn->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
1597 			pkt_off = meta_len;
1598 		else
1599 			pkt_off = nn->rx_offset;
1600 		data_off = NFP_NET_RX_BUF_HEADROOM + pkt_off;
1601 
1602 		/* Stats update */
1603 		u64_stats_update_begin(&r_vec->rx_sync);
1604 		r_vec->rx_pkts++;
1605 		r_vec->rx_bytes += pkt_len;
1606 		u64_stats_update_end(&r_vec->rx_sync);
1607 
1608 		if (xdp_prog && !(rxd->rxd.flags & PCIE_DESC_RX_BPF &&
1609 				  nn->bpf_offload_xdp)) {
1610 			int act;
1611 
1612 			dma_sync_single_for_cpu(&nn->pdev->dev,
1613 						rxbuf->dma_addr + pkt_off,
1614 						pkt_len, DMA_FROM_DEVICE);
1615 			act = nfp_net_run_xdp(xdp_prog, rxbuf->frag + data_off,
1616 					      pkt_len);
1617 			switch (act) {
1618 			case XDP_PASS:
1619 				break;
1620 			case XDP_TX:
1621 				if (unlikely(!nfp_net_tx_xdp_buf(nn, rx_ring,
1622 								 tx_ring, rxbuf,
1623 								 pkt_off, pkt_len)))
1624 					trace_xdp_exception(nn->netdev, xdp_prog, act);
1625 				continue;
1626 			default:
1627 				bpf_warn_invalid_xdp_action(act);
1628 			case XDP_ABORTED:
1629 				trace_xdp_exception(nn->netdev, xdp_prog, act);
1630 			case XDP_DROP:
1631 				nfp_net_rx_give_one(rx_ring, rxbuf->frag,
1632 						    rxbuf->dma_addr);
1633 				continue;
1634 			}
1635 		}
1636 
1637 		skb = build_skb(rxbuf->frag, true_bufsz);
1638 		if (unlikely(!skb)) {
1639 			nfp_net_rx_drop(r_vec, rx_ring, rxbuf, NULL);
1640 			continue;
1641 		}
1642 		new_frag = nfp_net_napi_alloc_one(nn, rx_dma_map_dir,
1643 						  &new_dma_addr);
1644 		if (unlikely(!new_frag)) {
1645 			nfp_net_rx_drop(r_vec, rx_ring, rxbuf, skb);
1646 			continue;
1647 		}
1648 
1649 		nfp_net_dma_unmap_rx(nn, rxbuf->dma_addr, nn->fl_bufsz,
1650 				     rx_dma_map_dir);
1651 
1652 		nfp_net_rx_give_one(rx_ring, new_frag, new_dma_addr);
1653 
1654 		skb_reserve(skb, data_off);
1655 		skb_put(skb, pkt_len);
1656 
1657 		if (nn->fw_ver.major <= 3) {
1658 			nfp_net_set_hash_desc(nn->netdev, skb, rxd);
1659 		} else if (meta_len) {
1660 			void *end;
1661 
1662 			end = nfp_net_parse_meta(nn->netdev, skb, meta_len);
1663 			if (unlikely(end != skb->data)) {
1664 				nn_warn_ratelimit(nn, "invalid RX packet metadata\n");
1665 				nfp_net_rx_drop(r_vec, rx_ring, NULL, skb);
1666 				continue;
1667 			}
1668 		}
1669 
1670 		skb_record_rx_queue(skb, rx_ring->idx);
1671 		skb->protocol = eth_type_trans(skb, nn->netdev);
1672 
1673 		nfp_net_rx_csum(nn, r_vec, rxd, skb);
1674 
1675 		if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
1676 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
1677 					       le16_to_cpu(rxd->rxd.vlan));
1678 
1679 		napi_gro_receive(&rx_ring->r_vec->napi, skb);
1680 	}
1681 
1682 	if (xdp_prog && tx_ring->wr_ptr_add)
1683 		nfp_net_tx_xmit_more_flush(tx_ring);
1684 	rcu_read_unlock();
1685 
1686 	return pkts_polled;
1687 }
1688 
1689 /**
1690  * nfp_net_poll() - napi poll function
1691  * @napi:    NAPI structure
1692  * @budget:  NAPI budget
1693  *
1694  * Return: number of packets polled.
1695  */
1696 static int nfp_net_poll(struct napi_struct *napi, int budget)
1697 {
1698 	struct nfp_net_r_vector *r_vec =
1699 		container_of(napi, struct nfp_net_r_vector, napi);
1700 	unsigned int pkts_polled = 0;
1701 
1702 	if (r_vec->tx_ring)
1703 		nfp_net_tx_complete(r_vec->tx_ring);
1704 	if (r_vec->rx_ring) {
1705 		pkts_polled = nfp_net_rx(r_vec->rx_ring, budget);
1706 		if (r_vec->xdp_ring)
1707 			nfp_net_xdp_complete(r_vec->xdp_ring);
1708 	}
1709 
1710 	if (pkts_polled < budget) {
1711 		napi_complete_done(napi, pkts_polled);
1712 		nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
1713 	}
1714 
1715 	return pkts_polled;
1716 }
1717 
1718 /* Setup and Configuration
1719  */
1720 
1721 /**
1722  * nfp_net_tx_ring_free() - Free resources allocated to a TX ring
1723  * @tx_ring:   TX ring to free
1724  */
1725 static void nfp_net_tx_ring_free(struct nfp_net_tx_ring *tx_ring)
1726 {
1727 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
1728 	struct nfp_net *nn = r_vec->nfp_net;
1729 	struct pci_dev *pdev = nn->pdev;
1730 
1731 	kfree(tx_ring->txbufs);
1732 
1733 	if (tx_ring->txds)
1734 		dma_free_coherent(&pdev->dev, tx_ring->size,
1735 				  tx_ring->txds, tx_ring->dma);
1736 
1737 	tx_ring->cnt = 0;
1738 	tx_ring->txbufs = NULL;
1739 	tx_ring->txds = NULL;
1740 	tx_ring->dma = 0;
1741 	tx_ring->size = 0;
1742 }
1743 
1744 /**
1745  * nfp_net_tx_ring_alloc() - Allocate resource for a TX ring
1746  * @tx_ring:   TX Ring structure to allocate
1747  * @cnt:       Ring buffer count
1748  * @is_xdp:    True if ring will be used for XDP
1749  *
1750  * Return: 0 on success, negative errno otherwise.
1751  */
1752 static int
1753 nfp_net_tx_ring_alloc(struct nfp_net_tx_ring *tx_ring, u32 cnt, bool is_xdp)
1754 {
1755 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
1756 	struct nfp_net *nn = r_vec->nfp_net;
1757 	struct pci_dev *pdev = nn->pdev;
1758 	int sz;
1759 
1760 	tx_ring->cnt = cnt;
1761 
1762 	tx_ring->size = sizeof(*tx_ring->txds) * tx_ring->cnt;
1763 	tx_ring->txds = dma_zalloc_coherent(&pdev->dev, tx_ring->size,
1764 					    &tx_ring->dma, GFP_KERNEL);
1765 	if (!tx_ring->txds)
1766 		goto err_alloc;
1767 
1768 	sz = sizeof(*tx_ring->txbufs) * tx_ring->cnt;
1769 	tx_ring->txbufs = kzalloc(sz, GFP_KERNEL);
1770 	if (!tx_ring->txbufs)
1771 		goto err_alloc;
1772 
1773 	if (!is_xdp)
1774 		netif_set_xps_queue(nn->netdev, &r_vec->affinity_mask,
1775 				    tx_ring->idx);
1776 
1777 	nn_dbg(nn, "TxQ%02d: QCidx=%02d cnt=%d dma=%#llx host=%p %s\n",
1778 	       tx_ring->idx, tx_ring->qcidx,
1779 	       tx_ring->cnt, (unsigned long long)tx_ring->dma, tx_ring->txds,
1780 	       is_xdp ? "XDP" : "");
1781 
1782 	return 0;
1783 
1784 err_alloc:
1785 	nfp_net_tx_ring_free(tx_ring);
1786 	return -ENOMEM;
1787 }
1788 
1789 static struct nfp_net_tx_ring *
1790 nfp_net_tx_ring_set_prepare(struct nfp_net *nn, struct nfp_net_ring_set *s,
1791 			    unsigned int num_stack_tx_rings)
1792 {
1793 	struct nfp_net_tx_ring *rings;
1794 	unsigned int r;
1795 
1796 	rings = kcalloc(s->n_rings, sizeof(*rings), GFP_KERNEL);
1797 	if (!rings)
1798 		return NULL;
1799 
1800 	for (r = 0; r < s->n_rings; r++) {
1801 		int bias = 0;
1802 
1803 		if (r >= num_stack_tx_rings)
1804 			bias = num_stack_tx_rings;
1805 
1806 		nfp_net_tx_ring_init(&rings[r], &nn->r_vecs[r - bias], r);
1807 
1808 		if (nfp_net_tx_ring_alloc(&rings[r], s->dcnt, bias))
1809 			goto err_free_prev;
1810 	}
1811 
1812 	return s->rings = rings;
1813 
1814 err_free_prev:
1815 	while (r--)
1816 		nfp_net_tx_ring_free(&rings[r]);
1817 	kfree(rings);
1818 	return NULL;
1819 }
1820 
1821 static void
1822 nfp_net_tx_ring_set_swap(struct nfp_net *nn, struct nfp_net_ring_set *s)
1823 {
1824 	struct nfp_net_ring_set new = *s;
1825 
1826 	s->dcnt = nn->txd_cnt;
1827 	s->rings = nn->tx_rings;
1828 	s->n_rings = nn->num_tx_rings;
1829 
1830 	nn->txd_cnt = new.dcnt;
1831 	nn->tx_rings = new.rings;
1832 	nn->num_tx_rings = new.n_rings;
1833 }
1834 
1835 static void
1836 nfp_net_tx_ring_set_free(struct nfp_net *nn, struct nfp_net_ring_set *s)
1837 {
1838 	struct nfp_net_tx_ring *rings = s->rings;
1839 	unsigned int r;
1840 
1841 	for (r = 0; r < s->n_rings; r++)
1842 		nfp_net_tx_ring_free(&rings[r]);
1843 
1844 	kfree(rings);
1845 }
1846 
1847 /**
1848  * nfp_net_rx_ring_free() - Free resources allocated to a RX ring
1849  * @rx_ring:  RX ring to free
1850  */
1851 static void nfp_net_rx_ring_free(struct nfp_net_rx_ring *rx_ring)
1852 {
1853 	struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
1854 	struct nfp_net *nn = r_vec->nfp_net;
1855 	struct pci_dev *pdev = nn->pdev;
1856 
1857 	kfree(rx_ring->rxbufs);
1858 
1859 	if (rx_ring->rxds)
1860 		dma_free_coherent(&pdev->dev, rx_ring->size,
1861 				  rx_ring->rxds, rx_ring->dma);
1862 
1863 	rx_ring->cnt = 0;
1864 	rx_ring->rxbufs = NULL;
1865 	rx_ring->rxds = NULL;
1866 	rx_ring->dma = 0;
1867 	rx_ring->size = 0;
1868 }
1869 
1870 /**
1871  * nfp_net_rx_ring_alloc() - Allocate resource for a RX ring
1872  * @rx_ring:  RX ring to allocate
1873  * @fl_bufsz: Size of buffers to allocate
1874  * @cnt:      Ring buffer count
1875  *
1876  * Return: 0 on success, negative errno otherwise.
1877  */
1878 static int
1879 nfp_net_rx_ring_alloc(struct nfp_net_rx_ring *rx_ring, unsigned int fl_bufsz,
1880 		      u32 cnt)
1881 {
1882 	struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
1883 	struct nfp_net *nn = r_vec->nfp_net;
1884 	struct pci_dev *pdev = nn->pdev;
1885 	int sz;
1886 
1887 	rx_ring->cnt = cnt;
1888 	rx_ring->bufsz = fl_bufsz;
1889 
1890 	rx_ring->size = sizeof(*rx_ring->rxds) * rx_ring->cnt;
1891 	rx_ring->rxds = dma_zalloc_coherent(&pdev->dev, rx_ring->size,
1892 					    &rx_ring->dma, GFP_KERNEL);
1893 	if (!rx_ring->rxds)
1894 		goto err_alloc;
1895 
1896 	sz = sizeof(*rx_ring->rxbufs) * rx_ring->cnt;
1897 	rx_ring->rxbufs = kzalloc(sz, GFP_KERNEL);
1898 	if (!rx_ring->rxbufs)
1899 		goto err_alloc;
1900 
1901 	nn_dbg(nn, "RxQ%02d: FlQCidx=%02d RxQCidx=%02d cnt=%d dma=%#llx host=%p\n",
1902 	       rx_ring->idx, rx_ring->fl_qcidx, rx_ring->rx_qcidx,
1903 	       rx_ring->cnt, (unsigned long long)rx_ring->dma, rx_ring->rxds);
1904 
1905 	return 0;
1906 
1907 err_alloc:
1908 	nfp_net_rx_ring_free(rx_ring);
1909 	return -ENOMEM;
1910 }
1911 
1912 static struct nfp_net_rx_ring *
1913 nfp_net_rx_ring_set_prepare(struct nfp_net *nn, struct nfp_net_ring_set *s,
1914 			    bool xdp)
1915 {
1916 	unsigned int fl_bufsz =	nfp_net_calc_fl_bufsz(nn, s->mtu);
1917 	struct nfp_net_rx_ring *rings;
1918 	unsigned int r;
1919 
1920 	rings = kcalloc(s->n_rings, sizeof(*rings), GFP_KERNEL);
1921 	if (!rings)
1922 		return NULL;
1923 
1924 	for (r = 0; r < s->n_rings; r++) {
1925 		nfp_net_rx_ring_init(&rings[r], &nn->r_vecs[r], r);
1926 
1927 		if (nfp_net_rx_ring_alloc(&rings[r], fl_bufsz, s->dcnt))
1928 			goto err_free_prev;
1929 
1930 		if (nfp_net_rx_ring_bufs_alloc(nn, &rings[r], xdp))
1931 			goto err_free_ring;
1932 	}
1933 
1934 	return s->rings = rings;
1935 
1936 err_free_prev:
1937 	while (r--) {
1938 		nfp_net_rx_ring_bufs_free(nn, &rings[r], xdp);
1939 err_free_ring:
1940 		nfp_net_rx_ring_free(&rings[r]);
1941 	}
1942 	kfree(rings);
1943 	return NULL;
1944 }
1945 
1946 static void
1947 nfp_net_rx_ring_set_swap(struct nfp_net *nn, struct nfp_net_ring_set *s)
1948 {
1949 	struct nfp_net_ring_set new = *s;
1950 
1951 	s->mtu = nn->netdev->mtu;
1952 	s->dcnt = nn->rxd_cnt;
1953 	s->rings = nn->rx_rings;
1954 	s->n_rings = nn->num_rx_rings;
1955 
1956 	nn->netdev->mtu = new.mtu;
1957 	nn->fl_bufsz = nfp_net_calc_fl_bufsz(nn, new.mtu);
1958 	nn->rxd_cnt = new.dcnt;
1959 	nn->rx_rings = new.rings;
1960 	nn->num_rx_rings = new.n_rings;
1961 }
1962 
1963 static void
1964 nfp_net_rx_ring_set_free(struct nfp_net *nn, struct nfp_net_ring_set *s,
1965 			 bool xdp)
1966 {
1967 	struct nfp_net_rx_ring *rings = s->rings;
1968 	unsigned int r;
1969 
1970 	for (r = 0; r < s->n_rings; r++) {
1971 		nfp_net_rx_ring_bufs_free(nn, &rings[r], xdp);
1972 		nfp_net_rx_ring_free(&rings[r]);
1973 	}
1974 
1975 	kfree(rings);
1976 }
1977 
1978 static void
1979 nfp_net_vector_assign_rings(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
1980 			    int idx)
1981 {
1982 	r_vec->rx_ring = idx < nn->num_rx_rings ? &nn->rx_rings[idx] : NULL;
1983 	r_vec->tx_ring =
1984 		idx < nn->num_stack_tx_rings ? &nn->tx_rings[idx] : NULL;
1985 
1986 	r_vec->xdp_ring = idx < nn->num_tx_rings - nn->num_stack_tx_rings ?
1987 		&nn->tx_rings[nn->num_stack_tx_rings + idx] : NULL;
1988 }
1989 
1990 static int
1991 nfp_net_prepare_vector(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
1992 		       int idx)
1993 {
1994 	int err;
1995 
1996 	/* Setup NAPI */
1997 	netif_napi_add(nn->netdev, &r_vec->napi,
1998 		       nfp_net_poll, NAPI_POLL_WEIGHT);
1999 
2000 	snprintf(r_vec->name, sizeof(r_vec->name),
2001 		 "%s-rxtx-%d", nn->netdev->name, idx);
2002 	err = request_irq(r_vec->irq_vector, r_vec->handler, 0, r_vec->name,
2003 			  r_vec);
2004 	if (err) {
2005 		netif_napi_del(&r_vec->napi);
2006 		nn_err(nn, "Error requesting IRQ %d\n", r_vec->irq_vector);
2007 		return err;
2008 	}
2009 	disable_irq(r_vec->irq_vector);
2010 
2011 	irq_set_affinity_hint(r_vec->irq_vector, &r_vec->affinity_mask);
2012 
2013 	nn_dbg(nn, "RV%02d: irq=%03d/%03d\n", idx, r_vec->irq_vector,
2014 	       r_vec->irq_entry);
2015 
2016 	return 0;
2017 }
2018 
2019 static void
2020 nfp_net_cleanup_vector(struct nfp_net *nn, struct nfp_net_r_vector *r_vec)
2021 {
2022 	irq_set_affinity_hint(r_vec->irq_vector, NULL);
2023 	netif_napi_del(&r_vec->napi);
2024 	free_irq(r_vec->irq_vector, r_vec);
2025 }
2026 
2027 /**
2028  * nfp_net_rss_write_itbl() - Write RSS indirection table to device
2029  * @nn:      NFP Net device to reconfigure
2030  */
2031 void nfp_net_rss_write_itbl(struct nfp_net *nn)
2032 {
2033 	int i;
2034 
2035 	for (i = 0; i < NFP_NET_CFG_RSS_ITBL_SZ; i += 4)
2036 		nn_writel(nn, NFP_NET_CFG_RSS_ITBL + i,
2037 			  get_unaligned_le32(nn->rss_itbl + i));
2038 }
2039 
2040 /**
2041  * nfp_net_rss_write_key() - Write RSS hash key to device
2042  * @nn:      NFP Net device to reconfigure
2043  */
2044 void nfp_net_rss_write_key(struct nfp_net *nn)
2045 {
2046 	int i;
2047 
2048 	for (i = 0; i < NFP_NET_CFG_RSS_KEY_SZ; i += 4)
2049 		nn_writel(nn, NFP_NET_CFG_RSS_KEY + i,
2050 			  get_unaligned_le32(nn->rss_key + i));
2051 }
2052 
2053 /**
2054  * nfp_net_coalesce_write_cfg() - Write irq coalescence configuration to HW
2055  * @nn:      NFP Net device to reconfigure
2056  */
2057 void nfp_net_coalesce_write_cfg(struct nfp_net *nn)
2058 {
2059 	u8 i;
2060 	u32 factor;
2061 	u32 value;
2062 
2063 	/* Compute factor used to convert coalesce '_usecs' parameters to
2064 	 * ME timestamp ticks.  There are 16 ME clock cycles for each timestamp
2065 	 * count.
2066 	 */
2067 	factor = nn->me_freq_mhz / 16;
2068 
2069 	/* copy RX interrupt coalesce parameters */
2070 	value = (nn->rx_coalesce_max_frames << 16) |
2071 		(factor * nn->rx_coalesce_usecs);
2072 	for (i = 0; i < nn->num_rx_rings; i++)
2073 		nn_writel(nn, NFP_NET_CFG_RXR_IRQ_MOD(i), value);
2074 
2075 	/* copy TX interrupt coalesce parameters */
2076 	value = (nn->tx_coalesce_max_frames << 16) |
2077 		(factor * nn->tx_coalesce_usecs);
2078 	for (i = 0; i < nn->num_tx_rings; i++)
2079 		nn_writel(nn, NFP_NET_CFG_TXR_IRQ_MOD(i), value);
2080 }
2081 
2082 /**
2083  * nfp_net_write_mac_addr() - Write mac address to the device control BAR
2084  * @nn:      NFP Net device to reconfigure
2085  *
2086  * Writes the MAC address from the netdev to the device control BAR.  Does not
2087  * perform the required reconfig.  We do a bit of byte swapping dance because
2088  * firmware is LE.
2089  */
2090 static void nfp_net_write_mac_addr(struct nfp_net *nn)
2091 {
2092 	nn_writel(nn, NFP_NET_CFG_MACADDR + 0,
2093 		  get_unaligned_be32(nn->netdev->dev_addr));
2094 	nn_writew(nn, NFP_NET_CFG_MACADDR + 6,
2095 		  get_unaligned_be16(nn->netdev->dev_addr + 4));
2096 }
2097 
2098 static void nfp_net_vec_clear_ring_data(struct nfp_net *nn, unsigned int idx)
2099 {
2100 	nn_writeq(nn, NFP_NET_CFG_RXR_ADDR(idx), 0);
2101 	nn_writeb(nn, NFP_NET_CFG_RXR_SZ(idx), 0);
2102 	nn_writeb(nn, NFP_NET_CFG_RXR_VEC(idx), 0);
2103 
2104 	nn_writeq(nn, NFP_NET_CFG_TXR_ADDR(idx), 0);
2105 	nn_writeb(nn, NFP_NET_CFG_TXR_SZ(idx), 0);
2106 	nn_writeb(nn, NFP_NET_CFG_TXR_VEC(idx), 0);
2107 }
2108 
2109 /**
2110  * nfp_net_clear_config_and_disable() - Clear control BAR and disable NFP
2111  * @nn:      NFP Net device to reconfigure
2112  */
2113 static void nfp_net_clear_config_and_disable(struct nfp_net *nn)
2114 {
2115 	u32 new_ctrl, update;
2116 	unsigned int r;
2117 	int err;
2118 
2119 	new_ctrl = nn->ctrl;
2120 	new_ctrl &= ~NFP_NET_CFG_CTRL_ENABLE;
2121 	update = NFP_NET_CFG_UPDATE_GEN;
2122 	update |= NFP_NET_CFG_UPDATE_MSIX;
2123 	update |= NFP_NET_CFG_UPDATE_RING;
2124 
2125 	if (nn->cap & NFP_NET_CFG_CTRL_RINGCFG)
2126 		new_ctrl &= ~NFP_NET_CFG_CTRL_RINGCFG;
2127 
2128 	nn_writeq(nn, NFP_NET_CFG_TXRS_ENABLE, 0);
2129 	nn_writeq(nn, NFP_NET_CFG_RXRS_ENABLE, 0);
2130 
2131 	nn_writel(nn, NFP_NET_CFG_CTRL, new_ctrl);
2132 	err = nfp_net_reconfig(nn, update);
2133 	if (err)
2134 		nn_err(nn, "Could not disable device: %d\n", err);
2135 
2136 	for (r = 0; r < nn->num_rx_rings; r++)
2137 		nfp_net_rx_ring_reset(&nn->rx_rings[r]);
2138 	for (r = 0; r < nn->num_tx_rings; r++)
2139 		nfp_net_tx_ring_reset(nn, &nn->tx_rings[r]);
2140 	for (r = 0; r < nn->num_r_vecs; r++)
2141 		nfp_net_vec_clear_ring_data(nn, r);
2142 
2143 	nn->ctrl = new_ctrl;
2144 }
2145 
2146 static void
2147 nfp_net_rx_ring_hw_cfg_write(struct nfp_net *nn,
2148 			     struct nfp_net_rx_ring *rx_ring, unsigned int idx)
2149 {
2150 	/* Write the DMA address, size and MSI-X info to the device */
2151 	nn_writeq(nn, NFP_NET_CFG_RXR_ADDR(idx), rx_ring->dma);
2152 	nn_writeb(nn, NFP_NET_CFG_RXR_SZ(idx), ilog2(rx_ring->cnt));
2153 	nn_writeb(nn, NFP_NET_CFG_RXR_VEC(idx), rx_ring->r_vec->irq_entry);
2154 }
2155 
2156 static void
2157 nfp_net_tx_ring_hw_cfg_write(struct nfp_net *nn,
2158 			     struct nfp_net_tx_ring *tx_ring, unsigned int idx)
2159 {
2160 	nn_writeq(nn, NFP_NET_CFG_TXR_ADDR(idx), tx_ring->dma);
2161 	nn_writeb(nn, NFP_NET_CFG_TXR_SZ(idx), ilog2(tx_ring->cnt));
2162 	nn_writeb(nn, NFP_NET_CFG_TXR_VEC(idx), tx_ring->r_vec->irq_entry);
2163 }
2164 
2165 static int __nfp_net_set_config_and_enable(struct nfp_net *nn)
2166 {
2167 	u32 new_ctrl, update = 0;
2168 	unsigned int r;
2169 	int err;
2170 
2171 	new_ctrl = nn->ctrl;
2172 
2173 	if (nn->cap & NFP_NET_CFG_CTRL_RSS) {
2174 		nfp_net_rss_write_key(nn);
2175 		nfp_net_rss_write_itbl(nn);
2176 		nn_writel(nn, NFP_NET_CFG_RSS_CTRL, nn->rss_cfg);
2177 		update |= NFP_NET_CFG_UPDATE_RSS;
2178 	}
2179 
2180 	if (nn->cap & NFP_NET_CFG_CTRL_IRQMOD) {
2181 		nfp_net_coalesce_write_cfg(nn);
2182 
2183 		new_ctrl |= NFP_NET_CFG_CTRL_IRQMOD;
2184 		update |= NFP_NET_CFG_UPDATE_IRQMOD;
2185 	}
2186 
2187 	for (r = 0; r < nn->num_tx_rings; r++)
2188 		nfp_net_tx_ring_hw_cfg_write(nn, &nn->tx_rings[r], r);
2189 	for (r = 0; r < nn->num_rx_rings; r++)
2190 		nfp_net_rx_ring_hw_cfg_write(nn, &nn->rx_rings[r], r);
2191 
2192 	nn_writeq(nn, NFP_NET_CFG_TXRS_ENABLE, nn->num_tx_rings == 64 ?
2193 		  0xffffffffffffffffULL : ((u64)1 << nn->num_tx_rings) - 1);
2194 
2195 	nn_writeq(nn, NFP_NET_CFG_RXRS_ENABLE, nn->num_rx_rings == 64 ?
2196 		  0xffffffffffffffffULL : ((u64)1 << nn->num_rx_rings) - 1);
2197 
2198 	nfp_net_write_mac_addr(nn);
2199 
2200 	nn_writel(nn, NFP_NET_CFG_MTU, nn->netdev->mtu);
2201 	nn_writel(nn, NFP_NET_CFG_FLBUFSZ, nn->fl_bufsz);
2202 
2203 	/* Enable device */
2204 	new_ctrl |= NFP_NET_CFG_CTRL_ENABLE;
2205 	update |= NFP_NET_CFG_UPDATE_GEN;
2206 	update |= NFP_NET_CFG_UPDATE_MSIX;
2207 	update |= NFP_NET_CFG_UPDATE_RING;
2208 	if (nn->cap & NFP_NET_CFG_CTRL_RINGCFG)
2209 		new_ctrl |= NFP_NET_CFG_CTRL_RINGCFG;
2210 
2211 	nn_writel(nn, NFP_NET_CFG_CTRL, new_ctrl);
2212 	err = nfp_net_reconfig(nn, update);
2213 
2214 	nn->ctrl = new_ctrl;
2215 
2216 	for (r = 0; r < nn->num_rx_rings; r++)
2217 		nfp_net_rx_ring_fill_freelist(&nn->rx_rings[r]);
2218 
2219 	/* Since reconfiguration requests while NFP is down are ignored we
2220 	 * have to wipe the entire VXLAN configuration and reinitialize it.
2221 	 */
2222 	if (nn->ctrl & NFP_NET_CFG_CTRL_VXLAN) {
2223 		memset(&nn->vxlan_ports, 0, sizeof(nn->vxlan_ports));
2224 		memset(&nn->vxlan_usecnt, 0, sizeof(nn->vxlan_usecnt));
2225 		udp_tunnel_get_rx_info(nn->netdev);
2226 	}
2227 
2228 	return err;
2229 }
2230 
2231 /**
2232  * nfp_net_set_config_and_enable() - Write control BAR and enable NFP
2233  * @nn:      NFP Net device to reconfigure
2234  */
2235 static int nfp_net_set_config_and_enable(struct nfp_net *nn)
2236 {
2237 	int err;
2238 
2239 	err = __nfp_net_set_config_and_enable(nn);
2240 	if (err)
2241 		nfp_net_clear_config_and_disable(nn);
2242 
2243 	return err;
2244 }
2245 
2246 /**
2247  * nfp_net_open_stack() - Start the device from stack's perspective
2248  * @nn:      NFP Net device to reconfigure
2249  */
2250 static void nfp_net_open_stack(struct nfp_net *nn)
2251 {
2252 	unsigned int r;
2253 
2254 	for (r = 0; r < nn->num_r_vecs; r++) {
2255 		napi_enable(&nn->r_vecs[r].napi);
2256 		enable_irq(nn->r_vecs[r].irq_vector);
2257 	}
2258 
2259 	netif_tx_wake_all_queues(nn->netdev);
2260 
2261 	enable_irq(nn->irq_entries[NFP_NET_IRQ_LSC_IDX].vector);
2262 	nfp_net_read_link_status(nn);
2263 }
2264 
2265 static int nfp_net_netdev_open(struct net_device *netdev)
2266 {
2267 	struct nfp_net *nn = netdev_priv(netdev);
2268 	struct nfp_net_ring_set rx = {
2269 		.n_rings = nn->num_rx_rings,
2270 		.mtu = nn->netdev->mtu,
2271 		.dcnt = nn->rxd_cnt,
2272 	};
2273 	struct nfp_net_ring_set tx = {
2274 		.n_rings = nn->num_tx_rings,
2275 		.dcnt = nn->txd_cnt,
2276 	};
2277 	int err, r;
2278 
2279 	if (nn->ctrl & NFP_NET_CFG_CTRL_ENABLE) {
2280 		nn_err(nn, "Dev is already enabled: 0x%08x\n", nn->ctrl);
2281 		return -EBUSY;
2282 	}
2283 
2284 	/* Step 1: Allocate resources for rings and the like
2285 	 * - Request interrupts
2286 	 * - Allocate RX and TX ring resources
2287 	 * - Setup initial RSS table
2288 	 */
2289 	err = nfp_net_aux_irq_request(nn, NFP_NET_CFG_EXN, "%s-exn",
2290 				      nn->exn_name, sizeof(nn->exn_name),
2291 				      NFP_NET_IRQ_EXN_IDX, nn->exn_handler);
2292 	if (err)
2293 		return err;
2294 	err = nfp_net_aux_irq_request(nn, NFP_NET_CFG_LSC, "%s-lsc",
2295 				      nn->lsc_name, sizeof(nn->lsc_name),
2296 				      NFP_NET_IRQ_LSC_IDX, nn->lsc_handler);
2297 	if (err)
2298 		goto err_free_exn;
2299 	disable_irq(nn->irq_entries[NFP_NET_IRQ_LSC_IDX].vector);
2300 
2301 	for (r = 0; r < nn->num_r_vecs; r++) {
2302 		err = nfp_net_prepare_vector(nn, &nn->r_vecs[r], r);
2303 		if (err)
2304 			goto err_cleanup_vec_p;
2305 	}
2306 
2307 	nn->rx_rings = nfp_net_rx_ring_set_prepare(nn, &rx, nn->xdp_prog);
2308 	if (!nn->rx_rings) {
2309 		err = -ENOMEM;
2310 		goto err_cleanup_vec;
2311 	}
2312 
2313 	nn->tx_rings = nfp_net_tx_ring_set_prepare(nn, &tx,
2314 						   nn->num_stack_tx_rings);
2315 	if (!nn->tx_rings) {
2316 		err = -ENOMEM;
2317 		goto err_free_rx_rings;
2318 	}
2319 
2320 	for (r = 0; r < nn->max_r_vecs; r++)
2321 		nfp_net_vector_assign_rings(nn, &nn->r_vecs[r], r);
2322 
2323 	err = netif_set_real_num_tx_queues(netdev, nn->num_stack_tx_rings);
2324 	if (err)
2325 		goto err_free_rings;
2326 
2327 	err = netif_set_real_num_rx_queues(netdev, nn->num_rx_rings);
2328 	if (err)
2329 		goto err_free_rings;
2330 
2331 	/* Step 2: Configure the NFP
2332 	 * - Enable rings from 0 to tx_rings/rx_rings - 1.
2333 	 * - Write MAC address (in case it changed)
2334 	 * - Set the MTU
2335 	 * - Set the Freelist buffer size
2336 	 * - Enable the FW
2337 	 */
2338 	err = nfp_net_set_config_and_enable(nn);
2339 	if (err)
2340 		goto err_free_rings;
2341 
2342 	/* Step 3: Enable for kernel
2343 	 * - put some freelist descriptors on each RX ring
2344 	 * - enable NAPI on each ring
2345 	 * - enable all TX queues
2346 	 * - set link state
2347 	 */
2348 	nfp_net_open_stack(nn);
2349 
2350 	return 0;
2351 
2352 err_free_rings:
2353 	nfp_net_tx_ring_set_free(nn, &tx);
2354 err_free_rx_rings:
2355 	nfp_net_rx_ring_set_free(nn, &rx, nn->xdp_prog);
2356 err_cleanup_vec:
2357 	r = nn->num_r_vecs;
2358 err_cleanup_vec_p:
2359 	while (r--)
2360 		nfp_net_cleanup_vector(nn, &nn->r_vecs[r]);
2361 	nfp_net_aux_irq_free(nn, NFP_NET_CFG_LSC, NFP_NET_IRQ_LSC_IDX);
2362 err_free_exn:
2363 	nfp_net_aux_irq_free(nn, NFP_NET_CFG_EXN, NFP_NET_IRQ_EXN_IDX);
2364 	return err;
2365 }
2366 
2367 /**
2368  * nfp_net_close_stack() - Quiescent the stack (part of close)
2369  * @nn:	     NFP Net device to reconfigure
2370  */
2371 static void nfp_net_close_stack(struct nfp_net *nn)
2372 {
2373 	unsigned int r;
2374 
2375 	disable_irq(nn->irq_entries[NFP_NET_IRQ_LSC_IDX].vector);
2376 	netif_carrier_off(nn->netdev);
2377 	nn->link_up = false;
2378 
2379 	for (r = 0; r < nn->num_r_vecs; r++) {
2380 		disable_irq(nn->r_vecs[r].irq_vector);
2381 		napi_disable(&nn->r_vecs[r].napi);
2382 	}
2383 
2384 	netif_tx_disable(nn->netdev);
2385 }
2386 
2387 /**
2388  * nfp_net_close_free_all() - Free all runtime resources
2389  * @nn:      NFP Net device to reconfigure
2390  */
2391 static void nfp_net_close_free_all(struct nfp_net *nn)
2392 {
2393 	unsigned int r;
2394 
2395 	for (r = 0; r < nn->num_rx_rings; r++) {
2396 		nfp_net_rx_ring_bufs_free(nn, &nn->rx_rings[r], nn->xdp_prog);
2397 		nfp_net_rx_ring_free(&nn->rx_rings[r]);
2398 	}
2399 	for (r = 0; r < nn->num_tx_rings; r++)
2400 		nfp_net_tx_ring_free(&nn->tx_rings[r]);
2401 	for (r = 0; r < nn->num_r_vecs; r++)
2402 		nfp_net_cleanup_vector(nn, &nn->r_vecs[r]);
2403 
2404 	kfree(nn->rx_rings);
2405 	kfree(nn->tx_rings);
2406 
2407 	nfp_net_aux_irq_free(nn, NFP_NET_CFG_LSC, NFP_NET_IRQ_LSC_IDX);
2408 	nfp_net_aux_irq_free(nn, NFP_NET_CFG_EXN, NFP_NET_IRQ_EXN_IDX);
2409 }
2410 
2411 /**
2412  * nfp_net_netdev_close() - Called when the device is downed
2413  * @netdev:      netdev structure
2414  */
2415 static int nfp_net_netdev_close(struct net_device *netdev)
2416 {
2417 	struct nfp_net *nn = netdev_priv(netdev);
2418 
2419 	if (!(nn->ctrl & NFP_NET_CFG_CTRL_ENABLE)) {
2420 		nn_err(nn, "Dev is not up: 0x%08x\n", nn->ctrl);
2421 		return 0;
2422 	}
2423 
2424 	/* Step 1: Disable RX and TX rings from the Linux kernel perspective
2425 	 */
2426 	nfp_net_close_stack(nn);
2427 
2428 	/* Step 2: Tell NFP
2429 	 */
2430 	nfp_net_clear_config_and_disable(nn);
2431 
2432 	/* Step 3: Free resources
2433 	 */
2434 	nfp_net_close_free_all(nn);
2435 
2436 	nn_dbg(nn, "%s down", netdev->name);
2437 	return 0;
2438 }
2439 
2440 static void nfp_net_set_rx_mode(struct net_device *netdev)
2441 {
2442 	struct nfp_net *nn = netdev_priv(netdev);
2443 	u32 new_ctrl;
2444 
2445 	new_ctrl = nn->ctrl;
2446 
2447 	if (netdev->flags & IFF_PROMISC) {
2448 		if (nn->cap & NFP_NET_CFG_CTRL_PROMISC)
2449 			new_ctrl |= NFP_NET_CFG_CTRL_PROMISC;
2450 		else
2451 			nn_warn(nn, "FW does not support promiscuous mode\n");
2452 	} else {
2453 		new_ctrl &= ~NFP_NET_CFG_CTRL_PROMISC;
2454 	}
2455 
2456 	if (new_ctrl == nn->ctrl)
2457 		return;
2458 
2459 	nn_writel(nn, NFP_NET_CFG_CTRL, new_ctrl);
2460 	nfp_net_reconfig_post(nn, NFP_NET_CFG_UPDATE_GEN);
2461 
2462 	nn->ctrl = new_ctrl;
2463 }
2464 
2465 static void nfp_net_rss_init_itbl(struct nfp_net *nn)
2466 {
2467 	int i;
2468 
2469 	for (i = 0; i < sizeof(nn->rss_itbl); i++)
2470 		nn->rss_itbl[i] =
2471 			ethtool_rxfh_indir_default(i, nn->num_rx_rings);
2472 }
2473 
2474 static int
2475 nfp_net_ring_swap_enable(struct nfp_net *nn, unsigned int *num_vecs,
2476 			 unsigned int *stack_tx_rings,
2477 			 struct bpf_prog **xdp_prog,
2478 			 struct nfp_net_ring_set *rx,
2479 			 struct nfp_net_ring_set *tx)
2480 {
2481 	unsigned int r;
2482 	int err;
2483 
2484 	if (rx)
2485 		nfp_net_rx_ring_set_swap(nn, rx);
2486 	if (tx)
2487 		nfp_net_tx_ring_set_swap(nn, tx);
2488 
2489 	swap(*num_vecs, nn->num_r_vecs);
2490 	swap(*stack_tx_rings, nn->num_stack_tx_rings);
2491 	*xdp_prog = xchg(&nn->xdp_prog, *xdp_prog);
2492 
2493 	for (r = 0; r <	nn->max_r_vecs; r++)
2494 		nfp_net_vector_assign_rings(nn, &nn->r_vecs[r], r);
2495 
2496 	if (!netif_is_rxfh_configured(nn->netdev))
2497 		nfp_net_rss_init_itbl(nn);
2498 
2499 	err = netif_set_real_num_rx_queues(nn->netdev,
2500 					   nn->num_rx_rings);
2501 	if (err)
2502 		return err;
2503 
2504 	if (nn->netdev->real_num_tx_queues != nn->num_stack_tx_rings) {
2505 		err = netif_set_real_num_tx_queues(nn->netdev,
2506 						   nn->num_stack_tx_rings);
2507 		if (err)
2508 			return err;
2509 	}
2510 
2511 	return __nfp_net_set_config_and_enable(nn);
2512 }
2513 
2514 static int
2515 nfp_net_check_config(struct nfp_net *nn, struct bpf_prog *xdp_prog,
2516 		     struct nfp_net_ring_set *rx, struct nfp_net_ring_set *tx)
2517 {
2518 	/* XDP-enabled tests */
2519 	if (!xdp_prog)
2520 		return 0;
2521 	if (rx && nfp_net_calc_fl_bufsz(nn, rx->mtu) > PAGE_SIZE) {
2522 		nn_warn(nn, "MTU too large w/ XDP enabled\n");
2523 		return -EINVAL;
2524 	}
2525 	if (tx && tx->n_rings > nn->max_tx_rings) {
2526 		nn_warn(nn, "Insufficient number of TX rings w/ XDP enabled\n");
2527 		return -EINVAL;
2528 	}
2529 
2530 	return 0;
2531 }
2532 
2533 static void
2534 nfp_net_ring_reconfig_down(struct nfp_net *nn, struct bpf_prog **xdp_prog,
2535 			   struct nfp_net_ring_set *rx,
2536 			   struct nfp_net_ring_set *tx,
2537 			   unsigned int stack_tx_rings, unsigned int num_vecs)
2538 {
2539 	nn->netdev->mtu = rx ? rx->mtu : nn->netdev->mtu;
2540 	nn->fl_bufsz = nfp_net_calc_fl_bufsz(nn, nn->netdev->mtu);
2541 	nn->rxd_cnt = rx ? rx->dcnt : nn->rxd_cnt;
2542 	nn->txd_cnt = tx ? tx->dcnt : nn->txd_cnt;
2543 	nn->num_rx_rings = rx ? rx->n_rings : nn->num_rx_rings;
2544 	nn->num_tx_rings = tx ? tx->n_rings : nn->num_tx_rings;
2545 	nn->num_stack_tx_rings = stack_tx_rings;
2546 	nn->num_r_vecs = num_vecs;
2547 	*xdp_prog = xchg(&nn->xdp_prog, *xdp_prog);
2548 
2549 	if (!netif_is_rxfh_configured(nn->netdev))
2550 		nfp_net_rss_init_itbl(nn);
2551 }
2552 
2553 int
2554 nfp_net_ring_reconfig(struct nfp_net *nn, struct bpf_prog **xdp_prog,
2555 		      struct nfp_net_ring_set *rx, struct nfp_net_ring_set *tx)
2556 {
2557 	unsigned int stack_tx_rings, num_vecs, r;
2558 	int err;
2559 
2560 	stack_tx_rings = tx ? tx->n_rings : nn->num_tx_rings;
2561 	if (*xdp_prog)
2562 		stack_tx_rings -= rx ? rx->n_rings : nn->num_rx_rings;
2563 
2564 	num_vecs = max(rx ? rx->n_rings : nn->num_rx_rings, stack_tx_rings);
2565 
2566 	err = nfp_net_check_config(nn, *xdp_prog, rx, tx);
2567 	if (err)
2568 		return err;
2569 
2570 	if (!netif_running(nn->netdev)) {
2571 		nfp_net_ring_reconfig_down(nn, xdp_prog, rx, tx,
2572 					   stack_tx_rings, num_vecs);
2573 		return 0;
2574 	}
2575 
2576 	/* Prepare new rings */
2577 	for (r = nn->num_r_vecs; r < num_vecs; r++) {
2578 		err = nfp_net_prepare_vector(nn, &nn->r_vecs[r], r);
2579 		if (err) {
2580 			num_vecs = r;
2581 			goto err_cleanup_vecs;
2582 		}
2583 	}
2584 	if (rx) {
2585 		if (!nfp_net_rx_ring_set_prepare(nn, rx, *xdp_prog)) {
2586 			err = -ENOMEM;
2587 			goto err_cleanup_vecs;
2588 		}
2589 	}
2590 	if (tx) {
2591 		if (!nfp_net_tx_ring_set_prepare(nn, tx, stack_tx_rings)) {
2592 			err = -ENOMEM;
2593 			goto err_free_rx;
2594 		}
2595 	}
2596 
2597 	/* Stop device, swap in new rings, try to start the firmware */
2598 	nfp_net_close_stack(nn);
2599 	nfp_net_clear_config_and_disable(nn);
2600 
2601 	err = nfp_net_ring_swap_enable(nn, &num_vecs, &stack_tx_rings,
2602 				       xdp_prog, rx, tx);
2603 	if (err) {
2604 		int err2;
2605 
2606 		nfp_net_clear_config_and_disable(nn);
2607 
2608 		/* Try with old configuration and old rings */
2609 		err2 = nfp_net_ring_swap_enable(nn, &num_vecs, &stack_tx_rings,
2610 						xdp_prog, rx, tx);
2611 		if (err2)
2612 			nn_err(nn, "Can't restore ring config - FW communication failed (%d,%d)\n",
2613 			       err, err2);
2614 	}
2615 	for (r = num_vecs - 1; r >= nn->num_r_vecs; r--)
2616 		nfp_net_cleanup_vector(nn, &nn->r_vecs[r]);
2617 
2618 	if (rx)
2619 		nfp_net_rx_ring_set_free(nn, rx, *xdp_prog);
2620 	if (tx)
2621 		nfp_net_tx_ring_set_free(nn, tx);
2622 
2623 	nfp_net_open_stack(nn);
2624 
2625 	return err;
2626 
2627 err_free_rx:
2628 	if (rx)
2629 		nfp_net_rx_ring_set_free(nn, rx, *xdp_prog);
2630 err_cleanup_vecs:
2631 	for (r = num_vecs - 1; r >= nn->num_r_vecs; r--)
2632 		nfp_net_cleanup_vector(nn, &nn->r_vecs[r]);
2633 	return err;
2634 }
2635 
2636 static int nfp_net_change_mtu(struct net_device *netdev, int new_mtu)
2637 {
2638 	struct nfp_net *nn = netdev_priv(netdev);
2639 	struct nfp_net_ring_set rx = {
2640 		.n_rings = nn->num_rx_rings,
2641 		.mtu = new_mtu,
2642 		.dcnt = nn->rxd_cnt,
2643 	};
2644 
2645 	return nfp_net_ring_reconfig(nn, &nn->xdp_prog, &rx, NULL);
2646 }
2647 
2648 static void nfp_net_stat64(struct net_device *netdev,
2649 			   struct rtnl_link_stats64 *stats)
2650 {
2651 	struct nfp_net *nn = netdev_priv(netdev);
2652 	int r;
2653 
2654 	for (r = 0; r < nn->num_r_vecs; r++) {
2655 		struct nfp_net_r_vector *r_vec = &nn->r_vecs[r];
2656 		u64 data[3];
2657 		unsigned int start;
2658 
2659 		do {
2660 			start = u64_stats_fetch_begin(&r_vec->rx_sync);
2661 			data[0] = r_vec->rx_pkts;
2662 			data[1] = r_vec->rx_bytes;
2663 			data[2] = r_vec->rx_drops;
2664 		} while (u64_stats_fetch_retry(&r_vec->rx_sync, start));
2665 		stats->rx_packets += data[0];
2666 		stats->rx_bytes += data[1];
2667 		stats->rx_dropped += data[2];
2668 
2669 		do {
2670 			start = u64_stats_fetch_begin(&r_vec->tx_sync);
2671 			data[0] = r_vec->tx_pkts;
2672 			data[1] = r_vec->tx_bytes;
2673 			data[2] = r_vec->tx_errors;
2674 		} while (u64_stats_fetch_retry(&r_vec->tx_sync, start));
2675 		stats->tx_packets += data[0];
2676 		stats->tx_bytes += data[1];
2677 		stats->tx_errors += data[2];
2678 	}
2679 }
2680 
2681 static bool nfp_net_ebpf_capable(struct nfp_net *nn)
2682 {
2683 	if (nn->cap & NFP_NET_CFG_CTRL_BPF &&
2684 	    nn_readb(nn, NFP_NET_CFG_BPF_ABI) == NFP_NET_BPF_ABI)
2685 		return true;
2686 	return false;
2687 }
2688 
2689 static int
2690 nfp_net_setup_tc(struct net_device *netdev, u32 handle, __be16 proto,
2691 		 struct tc_to_netdev *tc)
2692 {
2693 	struct nfp_net *nn = netdev_priv(netdev);
2694 
2695 	if (TC_H_MAJ(handle) != TC_H_MAJ(TC_H_INGRESS))
2696 		return -ENOTSUPP;
2697 	if (proto != htons(ETH_P_ALL))
2698 		return -ENOTSUPP;
2699 
2700 	if (tc->type == TC_SETUP_CLSBPF && nfp_net_ebpf_capable(nn)) {
2701 		if (!nn->bpf_offload_xdp)
2702 			return nfp_net_bpf_offload(nn, tc->cls_bpf);
2703 		else
2704 			return -EBUSY;
2705 	}
2706 
2707 	return -EINVAL;
2708 }
2709 
2710 static int nfp_net_set_features(struct net_device *netdev,
2711 				netdev_features_t features)
2712 {
2713 	netdev_features_t changed = netdev->features ^ features;
2714 	struct nfp_net *nn = netdev_priv(netdev);
2715 	u32 new_ctrl;
2716 	int err;
2717 
2718 	/* Assume this is not called with features we have not advertised */
2719 
2720 	new_ctrl = nn->ctrl;
2721 
2722 	if (changed & NETIF_F_RXCSUM) {
2723 		if (features & NETIF_F_RXCSUM)
2724 			new_ctrl |= NFP_NET_CFG_CTRL_RXCSUM;
2725 		else
2726 			new_ctrl &= ~NFP_NET_CFG_CTRL_RXCSUM;
2727 	}
2728 
2729 	if (changed & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) {
2730 		if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))
2731 			new_ctrl |= NFP_NET_CFG_CTRL_TXCSUM;
2732 		else
2733 			new_ctrl &= ~NFP_NET_CFG_CTRL_TXCSUM;
2734 	}
2735 
2736 	if (changed & (NETIF_F_TSO | NETIF_F_TSO6)) {
2737 		if (features & (NETIF_F_TSO | NETIF_F_TSO6))
2738 			new_ctrl |= NFP_NET_CFG_CTRL_LSO;
2739 		else
2740 			new_ctrl &= ~NFP_NET_CFG_CTRL_LSO;
2741 	}
2742 
2743 	if (changed & NETIF_F_HW_VLAN_CTAG_RX) {
2744 		if (features & NETIF_F_HW_VLAN_CTAG_RX)
2745 			new_ctrl |= NFP_NET_CFG_CTRL_RXVLAN;
2746 		else
2747 			new_ctrl &= ~NFP_NET_CFG_CTRL_RXVLAN;
2748 	}
2749 
2750 	if (changed & NETIF_F_HW_VLAN_CTAG_TX) {
2751 		if (features & NETIF_F_HW_VLAN_CTAG_TX)
2752 			new_ctrl |= NFP_NET_CFG_CTRL_TXVLAN;
2753 		else
2754 			new_ctrl &= ~NFP_NET_CFG_CTRL_TXVLAN;
2755 	}
2756 
2757 	if (changed & NETIF_F_SG) {
2758 		if (features & NETIF_F_SG)
2759 			new_ctrl |= NFP_NET_CFG_CTRL_GATHER;
2760 		else
2761 			new_ctrl &= ~NFP_NET_CFG_CTRL_GATHER;
2762 	}
2763 
2764 	if (changed & NETIF_F_HW_TC && nn->ctrl & NFP_NET_CFG_CTRL_BPF) {
2765 		nn_err(nn, "Cannot disable HW TC offload while in use\n");
2766 		return -EBUSY;
2767 	}
2768 
2769 	nn_dbg(nn, "Feature change 0x%llx -> 0x%llx (changed=0x%llx)\n",
2770 	       netdev->features, features, changed);
2771 
2772 	if (new_ctrl == nn->ctrl)
2773 		return 0;
2774 
2775 	nn_dbg(nn, "NIC ctrl: 0x%x -> 0x%x\n", nn->ctrl, new_ctrl);
2776 	nn_writel(nn, NFP_NET_CFG_CTRL, new_ctrl);
2777 	err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN);
2778 	if (err)
2779 		return err;
2780 
2781 	nn->ctrl = new_ctrl;
2782 
2783 	return 0;
2784 }
2785 
2786 static netdev_features_t
2787 nfp_net_features_check(struct sk_buff *skb, struct net_device *dev,
2788 		       netdev_features_t features)
2789 {
2790 	u8 l4_hdr;
2791 
2792 	/* We can't do TSO over double tagged packets (802.1AD) */
2793 	features &= vlan_features_check(skb, features);
2794 
2795 	if (!skb->encapsulation)
2796 		return features;
2797 
2798 	/* Ensure that inner L4 header offset fits into TX descriptor field */
2799 	if (skb_is_gso(skb)) {
2800 		u32 hdrlen;
2801 
2802 		hdrlen = skb_inner_transport_header(skb) - skb->data +
2803 			inner_tcp_hdrlen(skb);
2804 
2805 		if (unlikely(hdrlen > NFP_NET_LSO_MAX_HDR_SZ))
2806 			features &= ~NETIF_F_GSO_MASK;
2807 	}
2808 
2809 	/* VXLAN/GRE check */
2810 	switch (vlan_get_protocol(skb)) {
2811 	case htons(ETH_P_IP):
2812 		l4_hdr = ip_hdr(skb)->protocol;
2813 		break;
2814 	case htons(ETH_P_IPV6):
2815 		l4_hdr = ipv6_hdr(skb)->nexthdr;
2816 		break;
2817 	default:
2818 		return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
2819 	}
2820 
2821 	if (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
2822 	    skb->inner_protocol != htons(ETH_P_TEB) ||
2823 	    (l4_hdr != IPPROTO_UDP && l4_hdr != IPPROTO_GRE) ||
2824 	    (l4_hdr == IPPROTO_UDP &&
2825 	     (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
2826 	      sizeof(struct udphdr) + sizeof(struct vxlanhdr))))
2827 		return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
2828 
2829 	return features;
2830 }
2831 
2832 /**
2833  * nfp_net_set_vxlan_port() - set vxlan port in SW and reconfigure HW
2834  * @nn:   NFP Net device to reconfigure
2835  * @idx:  Index into the port table where new port should be written
2836  * @port: UDP port to configure (pass zero to remove VXLAN port)
2837  */
2838 static void nfp_net_set_vxlan_port(struct nfp_net *nn, int idx, __be16 port)
2839 {
2840 	int i;
2841 
2842 	nn->vxlan_ports[idx] = port;
2843 
2844 	if (!(nn->ctrl & NFP_NET_CFG_CTRL_VXLAN))
2845 		return;
2846 
2847 	BUILD_BUG_ON(NFP_NET_N_VXLAN_PORTS & 1);
2848 	for (i = 0; i < NFP_NET_N_VXLAN_PORTS; i += 2)
2849 		nn_writel(nn, NFP_NET_CFG_VXLAN_PORT + i * sizeof(port),
2850 			  be16_to_cpu(nn->vxlan_ports[i + 1]) << 16 |
2851 			  be16_to_cpu(nn->vxlan_ports[i]));
2852 
2853 	nfp_net_reconfig_post(nn, NFP_NET_CFG_UPDATE_VXLAN);
2854 }
2855 
2856 /**
2857  * nfp_net_find_vxlan_idx() - find table entry of the port or a free one
2858  * @nn:   NFP Network structure
2859  * @port: UDP port to look for
2860  *
2861  * Return: if the port is already in the table -- it's position;
2862  *	   if the port is not in the table -- free position to use;
2863  *	   if the table is full -- -ENOSPC.
2864  */
2865 static int nfp_net_find_vxlan_idx(struct nfp_net *nn, __be16 port)
2866 {
2867 	int i, free_idx = -ENOSPC;
2868 
2869 	for (i = 0; i < NFP_NET_N_VXLAN_PORTS; i++) {
2870 		if (nn->vxlan_ports[i] == port)
2871 			return i;
2872 		if (!nn->vxlan_usecnt[i])
2873 			free_idx = i;
2874 	}
2875 
2876 	return free_idx;
2877 }
2878 
2879 static void nfp_net_add_vxlan_port(struct net_device *netdev,
2880 				   struct udp_tunnel_info *ti)
2881 {
2882 	struct nfp_net *nn = netdev_priv(netdev);
2883 	int idx;
2884 
2885 	if (ti->type != UDP_TUNNEL_TYPE_VXLAN)
2886 		return;
2887 
2888 	idx = nfp_net_find_vxlan_idx(nn, ti->port);
2889 	if (idx == -ENOSPC)
2890 		return;
2891 
2892 	if (!nn->vxlan_usecnt[idx]++)
2893 		nfp_net_set_vxlan_port(nn, idx, ti->port);
2894 }
2895 
2896 static void nfp_net_del_vxlan_port(struct net_device *netdev,
2897 				   struct udp_tunnel_info *ti)
2898 {
2899 	struct nfp_net *nn = netdev_priv(netdev);
2900 	int idx;
2901 
2902 	if (ti->type != UDP_TUNNEL_TYPE_VXLAN)
2903 		return;
2904 
2905 	idx = nfp_net_find_vxlan_idx(nn, ti->port);
2906 	if (idx == -ENOSPC || !nn->vxlan_usecnt[idx])
2907 		return;
2908 
2909 	if (!--nn->vxlan_usecnt[idx])
2910 		nfp_net_set_vxlan_port(nn, idx, 0);
2911 }
2912 
2913 static int nfp_net_xdp_offload(struct nfp_net *nn, struct bpf_prog *prog)
2914 {
2915 	struct tc_cls_bpf_offload cmd = {
2916 		.prog = prog,
2917 	};
2918 	int ret;
2919 
2920 	if (!nfp_net_ebpf_capable(nn))
2921 		return -EINVAL;
2922 
2923 	if (nn->ctrl & NFP_NET_CFG_CTRL_BPF) {
2924 		if (!nn->bpf_offload_xdp)
2925 			return prog ? -EBUSY : 0;
2926 		cmd.command = prog ? TC_CLSBPF_REPLACE : TC_CLSBPF_DESTROY;
2927 	} else {
2928 		if (!prog)
2929 			return 0;
2930 		cmd.command = TC_CLSBPF_ADD;
2931 	}
2932 
2933 	ret = nfp_net_bpf_offload(nn, &cmd);
2934 	/* Stop offload if replace not possible */
2935 	if (ret && cmd.command == TC_CLSBPF_REPLACE)
2936 		nfp_net_xdp_offload(nn, NULL);
2937 	nn->bpf_offload_xdp = prog && !ret;
2938 	return ret;
2939 }
2940 
2941 static int nfp_net_xdp_setup(struct nfp_net *nn, struct bpf_prog *prog)
2942 {
2943 	struct nfp_net_ring_set rx = {
2944 		.n_rings = nn->num_rx_rings,
2945 		.mtu = nn->netdev->mtu,
2946 		.dcnt = nn->rxd_cnt,
2947 	};
2948 	struct nfp_net_ring_set tx = {
2949 		.n_rings = nn->num_tx_rings,
2950 		.dcnt = nn->txd_cnt,
2951 	};
2952 	int err;
2953 
2954 	if (prog && prog->xdp_adjust_head) {
2955 		nn_err(nn, "Does not support bpf_xdp_adjust_head()\n");
2956 		return -EOPNOTSUPP;
2957 	}
2958 	if (!prog && !nn->xdp_prog)
2959 		return 0;
2960 	if (prog && nn->xdp_prog) {
2961 		prog = xchg(&nn->xdp_prog, prog);
2962 		bpf_prog_put(prog);
2963 		nfp_net_xdp_offload(nn, nn->xdp_prog);
2964 		return 0;
2965 	}
2966 
2967 	tx.n_rings += prog ? nn->num_rx_rings : -nn->num_rx_rings;
2968 
2969 	/* We need RX reconfig to remap the buffers (BIDIR vs FROM_DEV) */
2970 	err = nfp_net_ring_reconfig(nn, &prog, &rx, &tx);
2971 	if (err)
2972 		return err;
2973 
2974 	/* @prog got swapped and is now the old one */
2975 	if (prog)
2976 		bpf_prog_put(prog);
2977 
2978 	nfp_net_xdp_offload(nn, nn->xdp_prog);
2979 
2980 	return 0;
2981 }
2982 
2983 static int nfp_net_xdp(struct net_device *netdev, struct netdev_xdp *xdp)
2984 {
2985 	struct nfp_net *nn = netdev_priv(netdev);
2986 
2987 	switch (xdp->command) {
2988 	case XDP_SETUP_PROG:
2989 		return nfp_net_xdp_setup(nn, xdp->prog);
2990 	case XDP_QUERY_PROG:
2991 		xdp->prog_attached = !!nn->xdp_prog;
2992 		return 0;
2993 	default:
2994 		return -EINVAL;
2995 	}
2996 }
2997 
2998 static const struct net_device_ops nfp_net_netdev_ops = {
2999 	.ndo_open		= nfp_net_netdev_open,
3000 	.ndo_stop		= nfp_net_netdev_close,
3001 	.ndo_start_xmit		= nfp_net_tx,
3002 	.ndo_get_stats64	= nfp_net_stat64,
3003 	.ndo_setup_tc		= nfp_net_setup_tc,
3004 	.ndo_tx_timeout		= nfp_net_tx_timeout,
3005 	.ndo_set_rx_mode	= nfp_net_set_rx_mode,
3006 	.ndo_change_mtu		= nfp_net_change_mtu,
3007 	.ndo_set_mac_address	= eth_mac_addr,
3008 	.ndo_set_features	= nfp_net_set_features,
3009 	.ndo_features_check	= nfp_net_features_check,
3010 	.ndo_udp_tunnel_add	= nfp_net_add_vxlan_port,
3011 	.ndo_udp_tunnel_del	= nfp_net_del_vxlan_port,
3012 	.ndo_xdp		= nfp_net_xdp,
3013 };
3014 
3015 /**
3016  * nfp_net_info() - Print general info about the NIC
3017  * @nn:      NFP Net device to reconfigure
3018  */
3019 void nfp_net_info(struct nfp_net *nn)
3020 {
3021 	nn_info(nn, "Netronome NFP-6xxx %sNetdev: TxQs=%d/%d RxQs=%d/%d\n",
3022 		nn->is_vf ? "VF " : "",
3023 		nn->num_tx_rings, nn->max_tx_rings,
3024 		nn->num_rx_rings, nn->max_rx_rings);
3025 	nn_info(nn, "VER: %d.%d.%d.%d, Maximum supported MTU: %d\n",
3026 		nn->fw_ver.resv, nn->fw_ver.class,
3027 		nn->fw_ver.major, nn->fw_ver.minor,
3028 		nn->max_mtu);
3029 	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
3030 		nn->cap,
3031 		nn->cap & NFP_NET_CFG_CTRL_PROMISC  ? "PROMISC "  : "",
3032 		nn->cap & NFP_NET_CFG_CTRL_L2BC     ? "L2BCFILT " : "",
3033 		nn->cap & NFP_NET_CFG_CTRL_L2MC     ? "L2MCFILT " : "",
3034 		nn->cap & NFP_NET_CFG_CTRL_RXCSUM   ? "RXCSUM "   : "",
3035 		nn->cap & NFP_NET_CFG_CTRL_TXCSUM   ? "TXCSUM "   : "",
3036 		nn->cap & NFP_NET_CFG_CTRL_RXVLAN   ? "RXVLAN "   : "",
3037 		nn->cap & NFP_NET_CFG_CTRL_TXVLAN   ? "TXVLAN "   : "",
3038 		nn->cap & NFP_NET_CFG_CTRL_SCATTER  ? "SCATTER "  : "",
3039 		nn->cap & NFP_NET_CFG_CTRL_GATHER   ? "GATHER "   : "",
3040 		nn->cap & NFP_NET_CFG_CTRL_LSO      ? "TSO "      : "",
3041 		nn->cap & NFP_NET_CFG_CTRL_RSS      ? "RSS "      : "",
3042 		nn->cap & NFP_NET_CFG_CTRL_L2SWITCH ? "L2SWITCH " : "",
3043 		nn->cap & NFP_NET_CFG_CTRL_MSIXAUTO ? "AUTOMASK " : "",
3044 		nn->cap & NFP_NET_CFG_CTRL_IRQMOD   ? "IRQMOD "   : "",
3045 		nn->cap & NFP_NET_CFG_CTRL_VXLAN    ? "VXLAN "    : "",
3046 		nn->cap & NFP_NET_CFG_CTRL_NVGRE    ? "NVGRE "	  : "",
3047 		nfp_net_ebpf_capable(nn)            ? "BPF "	  : "");
3048 }
3049 
3050 /**
3051  * nfp_net_netdev_alloc() - Allocate netdev and related structure
3052  * @pdev:         PCI device
3053  * @max_tx_rings: Maximum number of TX rings supported by device
3054  * @max_rx_rings: Maximum number of RX rings supported by device
3055  *
3056  * This function allocates a netdev device and fills in the initial
3057  * part of the @struct nfp_net structure.
3058  *
3059  * Return: NFP Net device structure, or ERR_PTR on error.
3060  */
3061 struct nfp_net *nfp_net_netdev_alloc(struct pci_dev *pdev,
3062 				     unsigned int max_tx_rings,
3063 				     unsigned int max_rx_rings)
3064 {
3065 	struct net_device *netdev;
3066 	struct nfp_net *nn;
3067 
3068 	netdev = alloc_etherdev_mqs(sizeof(struct nfp_net),
3069 				    max_tx_rings, max_rx_rings);
3070 	if (!netdev)
3071 		return ERR_PTR(-ENOMEM);
3072 
3073 	SET_NETDEV_DEV(netdev, &pdev->dev);
3074 	nn = netdev_priv(netdev);
3075 
3076 	nn->netdev = netdev;
3077 	nn->pdev = pdev;
3078 
3079 	nn->max_tx_rings = max_tx_rings;
3080 	nn->max_rx_rings = max_rx_rings;
3081 
3082 	nn->num_tx_rings = min_t(unsigned int, max_tx_rings, num_online_cpus());
3083 	nn->num_rx_rings = min_t(unsigned int, max_rx_rings,
3084 				 netif_get_num_default_rss_queues());
3085 
3086 	nn->num_r_vecs = max(nn->num_tx_rings, nn->num_rx_rings);
3087 	nn->num_r_vecs = min_t(unsigned int, nn->num_r_vecs, num_online_cpus());
3088 
3089 	nn->txd_cnt = NFP_NET_TX_DESCS_DEFAULT;
3090 	nn->rxd_cnt = NFP_NET_RX_DESCS_DEFAULT;
3091 
3092 	spin_lock_init(&nn->reconfig_lock);
3093 	spin_lock_init(&nn->rx_filter_lock);
3094 	spin_lock_init(&nn->link_status_lock);
3095 
3096 	setup_timer(&nn->reconfig_timer,
3097 		    nfp_net_reconfig_timer, (unsigned long)nn);
3098 	setup_timer(&nn->rx_filter_stats_timer,
3099 		    nfp_net_filter_stats_timer, (unsigned long)nn);
3100 
3101 	return nn;
3102 }
3103 
3104 /**
3105  * nfp_net_netdev_free() - Undo what @nfp_net_netdev_alloc() did
3106  * @nn:      NFP Net device to reconfigure
3107  */
3108 void nfp_net_netdev_free(struct nfp_net *nn)
3109 {
3110 	free_netdev(nn->netdev);
3111 }
3112 
3113 /**
3114  * nfp_net_rss_init() - Set the initial RSS parameters
3115  * @nn:	     NFP Net device to reconfigure
3116  */
3117 static void nfp_net_rss_init(struct nfp_net *nn)
3118 {
3119 	netdev_rss_key_fill(nn->rss_key, NFP_NET_CFG_RSS_KEY_SZ);
3120 
3121 	nfp_net_rss_init_itbl(nn);
3122 
3123 	/* Enable IPv4/IPv6 TCP by default */
3124 	nn->rss_cfg = NFP_NET_CFG_RSS_IPV4_TCP |
3125 		      NFP_NET_CFG_RSS_IPV6_TCP |
3126 		      NFP_NET_CFG_RSS_TOEPLITZ |
3127 		      NFP_NET_CFG_RSS_MASK;
3128 }
3129 
3130 /**
3131  * nfp_net_irqmod_init() - Set the initial IRQ moderation parameters
3132  * @nn:	     NFP Net device to reconfigure
3133  */
3134 static void nfp_net_irqmod_init(struct nfp_net *nn)
3135 {
3136 	nn->rx_coalesce_usecs      = 50;
3137 	nn->rx_coalesce_max_frames = 64;
3138 	nn->tx_coalesce_usecs      = 50;
3139 	nn->tx_coalesce_max_frames = 64;
3140 }
3141 
3142 /**
3143  * nfp_net_netdev_init() - Initialise/finalise the netdev structure
3144  * @netdev:      netdev structure
3145  *
3146  * Return: 0 on success or negative errno on error.
3147  */
3148 int nfp_net_netdev_init(struct net_device *netdev)
3149 {
3150 	struct nfp_net *nn = netdev_priv(netdev);
3151 	int err;
3152 
3153 	/* Get some of the read-only fields from the BAR */
3154 	nn->cap = nn_readl(nn, NFP_NET_CFG_CAP);
3155 	nn->max_mtu = nn_readl(nn, NFP_NET_CFG_MAX_MTU);
3156 
3157 	nfp_net_write_mac_addr(nn);
3158 
3159 	/* Determine RX packet/metadata boundary offset */
3160 	if (nn->fw_ver.major >= 2)
3161 		nn->rx_offset = nn_readl(nn, NFP_NET_CFG_RX_OFFSET);
3162 	else
3163 		nn->rx_offset = NFP_NET_RX_OFFSET;
3164 
3165 	/* Set default MTU and Freelist buffer size */
3166 	if (nn->max_mtu < NFP_NET_DEFAULT_MTU)
3167 		netdev->mtu = nn->max_mtu;
3168 	else
3169 		netdev->mtu = NFP_NET_DEFAULT_MTU;
3170 	nn->fl_bufsz = nfp_net_calc_fl_bufsz(nn, netdev->mtu);
3171 
3172 	/* Advertise/enable offloads based on capabilities
3173 	 *
3174 	 * Note: netdev->features show the currently enabled features
3175 	 * and netdev->hw_features advertises which features are
3176 	 * supported.  By default we enable most features.
3177 	 */
3178 	netdev->hw_features = NETIF_F_HIGHDMA;
3179 	if (nn->cap & NFP_NET_CFG_CTRL_RXCSUM) {
3180 		netdev->hw_features |= NETIF_F_RXCSUM;
3181 		nn->ctrl |= NFP_NET_CFG_CTRL_RXCSUM;
3182 	}
3183 	if (nn->cap & NFP_NET_CFG_CTRL_TXCSUM) {
3184 		netdev->hw_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
3185 		nn->ctrl |= NFP_NET_CFG_CTRL_TXCSUM;
3186 	}
3187 	if (nn->cap & NFP_NET_CFG_CTRL_GATHER) {
3188 		netdev->hw_features |= NETIF_F_SG;
3189 		nn->ctrl |= NFP_NET_CFG_CTRL_GATHER;
3190 	}
3191 	if ((nn->cap & NFP_NET_CFG_CTRL_LSO) && nn->fw_ver.major > 2) {
3192 		netdev->hw_features |= NETIF_F_TSO | NETIF_F_TSO6;
3193 		nn->ctrl |= NFP_NET_CFG_CTRL_LSO;
3194 	}
3195 	if (nn->cap & NFP_NET_CFG_CTRL_RSS) {
3196 		netdev->hw_features |= NETIF_F_RXHASH;
3197 		nfp_net_rss_init(nn);
3198 		nn->ctrl |= NFP_NET_CFG_CTRL_RSS;
3199 	}
3200 	if (nn->cap & NFP_NET_CFG_CTRL_VXLAN &&
3201 	    nn->cap & NFP_NET_CFG_CTRL_NVGRE) {
3202 		if (nn->cap & NFP_NET_CFG_CTRL_LSO)
3203 			netdev->hw_features |= NETIF_F_GSO_GRE |
3204 					       NETIF_F_GSO_UDP_TUNNEL;
3205 		nn->ctrl |= NFP_NET_CFG_CTRL_VXLAN | NFP_NET_CFG_CTRL_NVGRE;
3206 
3207 		netdev->hw_enc_features = netdev->hw_features;
3208 	}
3209 
3210 	netdev->vlan_features = netdev->hw_features;
3211 
3212 	if (nn->cap & NFP_NET_CFG_CTRL_RXVLAN) {
3213 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_RX;
3214 		nn->ctrl |= NFP_NET_CFG_CTRL_RXVLAN;
3215 	}
3216 	if (nn->cap & NFP_NET_CFG_CTRL_TXVLAN) {
3217 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX;
3218 		nn->ctrl |= NFP_NET_CFG_CTRL_TXVLAN;
3219 	}
3220 
3221 	netdev->features = netdev->hw_features;
3222 
3223 	if (nfp_net_ebpf_capable(nn))
3224 		netdev->hw_features |= NETIF_F_HW_TC;
3225 
3226 	/* Advertise but disable TSO by default. */
3227 	netdev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
3228 
3229 	/* Allow L2 Broadcast and Multicast through by default, if supported */
3230 	if (nn->cap & NFP_NET_CFG_CTRL_L2BC)
3231 		nn->ctrl |= NFP_NET_CFG_CTRL_L2BC;
3232 	if (nn->cap & NFP_NET_CFG_CTRL_L2MC)
3233 		nn->ctrl |= NFP_NET_CFG_CTRL_L2MC;
3234 
3235 	/* Allow IRQ moderation, if supported */
3236 	if (nn->cap & NFP_NET_CFG_CTRL_IRQMOD) {
3237 		nfp_net_irqmod_init(nn);
3238 		nn->ctrl |= NFP_NET_CFG_CTRL_IRQMOD;
3239 	}
3240 
3241 	/* Stash the re-configuration queue away.  First odd queue in TX Bar */
3242 	nn->qcp_cfg = nn->tx_bar + NFP_QCP_QUEUE_ADDR_SZ;
3243 
3244 	/* Make sure the FW knows the netdev is supposed to be disabled here */
3245 	nn_writel(nn, NFP_NET_CFG_CTRL, 0);
3246 	nn_writeq(nn, NFP_NET_CFG_TXRS_ENABLE, 0);
3247 	nn_writeq(nn, NFP_NET_CFG_RXRS_ENABLE, 0);
3248 	err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_RING |
3249 				   NFP_NET_CFG_UPDATE_GEN);
3250 	if (err)
3251 		return err;
3252 
3253 	/* Finalise the netdev setup */
3254 	netdev->netdev_ops = &nfp_net_netdev_ops;
3255 	netdev->watchdog_timeo = msecs_to_jiffies(5 * 1000);
3256 
3257 	/* MTU range: 68 - hw-specific max */
3258 	netdev->min_mtu = ETH_MIN_MTU;
3259 	netdev->max_mtu = nn->max_mtu;
3260 
3261 	netif_carrier_off(netdev);
3262 
3263 	nfp_net_set_ethtool_ops(netdev);
3264 	nfp_net_vecs_init(netdev);
3265 
3266 	return register_netdev(netdev);
3267 }
3268 
3269 /**
3270  * nfp_net_netdev_clean() - Undo what nfp_net_netdev_init() did.
3271  * @netdev:      netdev structure
3272  */
3273 void nfp_net_netdev_clean(struct net_device *netdev)
3274 {
3275 	struct nfp_net *nn = netdev_priv(netdev);
3276 
3277 	if (nn->xdp_prog)
3278 		bpf_prog_put(nn->xdp_prog);
3279 	if (nn->bpf_offload_xdp)
3280 		nfp_net_xdp_offload(nn, NULL);
3281 	unregister_netdev(nn->netdev);
3282 }
3283