1 // SPDX-License-Identifier: GPL-2.0-only
2 /****************************************************************************
3  * Driver for Solarflare network controllers and boards
4  * Copyright 2018 Solarflare Communications Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published
8  * by the Free Software Foundation, incorporated herein by reference.
9  */
10 
11 #include "net_driver.h"
12 #include <linux/filter.h>
13 #include <linux/module.h>
14 #include <linux/netdevice.h>
15 #include <net/gre.h>
16 #include "efx_common.h"
17 #include "efx_channels.h"
18 #include "efx.h"
19 #include "mcdi.h"
20 #include "selftest.h"
21 #include "rx_common.h"
22 #include "tx_common.h"
23 #include "nic.h"
24 #include "mcdi_port_common.h"
25 #include "io.h"
26 #include "mcdi_pcol.h"
27 #include "ef100_rep.h"
28 
29 static unsigned int debug = (NETIF_MSG_DRV | NETIF_MSG_PROBE |
30 			     NETIF_MSG_LINK | NETIF_MSG_IFDOWN |
31 			     NETIF_MSG_IFUP | NETIF_MSG_RX_ERR |
32 			     NETIF_MSG_TX_ERR | NETIF_MSG_HW);
33 module_param(debug, uint, 0);
34 MODULE_PARM_DESC(debug, "Bitmapped debugging message enable value");
35 
36 /* This is the time (in jiffies) between invocations of the hardware
37  * monitor.
38  * On Falcon-based NICs, this will:
39  * - Check the on-board hardware monitor;
40  * - Poll the link state and reconfigure the hardware as necessary.
41  * On Siena-based NICs for power systems with EEH support, this will give EEH a
42  * chance to start.
43  */
44 static unsigned int efx_monitor_interval = 1 * HZ;
45 
46 /* How often and how many times to poll for a reset while waiting for a
47  * BIST that another function started to complete.
48  */
49 #define BIST_WAIT_DELAY_MS	100
50 #define BIST_WAIT_DELAY_COUNT	100
51 
52 /* Default stats update time */
53 #define STATS_PERIOD_MS_DEFAULT 1000
54 
55 static const unsigned int efx_reset_type_max = RESET_TYPE_MAX;
56 static const char *const efx_reset_type_names[] = {
57 	[RESET_TYPE_INVISIBLE]          = "INVISIBLE",
58 	[RESET_TYPE_ALL]                = "ALL",
59 	[RESET_TYPE_RECOVER_OR_ALL]     = "RECOVER_OR_ALL",
60 	[RESET_TYPE_WORLD]              = "WORLD",
61 	[RESET_TYPE_RECOVER_OR_DISABLE] = "RECOVER_OR_DISABLE",
62 	[RESET_TYPE_DATAPATH]           = "DATAPATH",
63 	[RESET_TYPE_MC_BIST]		= "MC_BIST",
64 	[RESET_TYPE_DISABLE]            = "DISABLE",
65 	[RESET_TYPE_TX_WATCHDOG]        = "TX_WATCHDOG",
66 	[RESET_TYPE_INT_ERROR]          = "INT_ERROR",
67 	[RESET_TYPE_DMA_ERROR]          = "DMA_ERROR",
68 	[RESET_TYPE_TX_SKIP]            = "TX_SKIP",
69 	[RESET_TYPE_MC_FAILURE]         = "MC_FAILURE",
70 	[RESET_TYPE_MCDI_TIMEOUT]	= "MCDI_TIMEOUT (FLR)",
71 };
72 
73 #define RESET_TYPE(type) \
74 	STRING_TABLE_LOOKUP(type, efx_reset_type)
75 
76 /* Loopback mode names (see LOOPBACK_MODE()) */
77 const unsigned int efx_loopback_mode_max = LOOPBACK_MAX;
78 const char *const efx_loopback_mode_names[] = {
79 	[LOOPBACK_NONE]		= "NONE",
80 	[LOOPBACK_DATA]		= "DATAPATH",
81 	[LOOPBACK_GMAC]		= "GMAC",
82 	[LOOPBACK_XGMII]	= "XGMII",
83 	[LOOPBACK_XGXS]		= "XGXS",
84 	[LOOPBACK_XAUI]		= "XAUI",
85 	[LOOPBACK_GMII]		= "GMII",
86 	[LOOPBACK_SGMII]	= "SGMII",
87 	[LOOPBACK_XGBR]		= "XGBR",
88 	[LOOPBACK_XFI]		= "XFI",
89 	[LOOPBACK_XAUI_FAR]	= "XAUI_FAR",
90 	[LOOPBACK_GMII_FAR]	= "GMII_FAR",
91 	[LOOPBACK_SGMII_FAR]	= "SGMII_FAR",
92 	[LOOPBACK_XFI_FAR]	= "XFI_FAR",
93 	[LOOPBACK_GPHY]		= "GPHY",
94 	[LOOPBACK_PHYXS]	= "PHYXS",
95 	[LOOPBACK_PCS]		= "PCS",
96 	[LOOPBACK_PMAPMD]	= "PMA/PMD",
97 	[LOOPBACK_XPORT]	= "XPORT",
98 	[LOOPBACK_XGMII_WS]	= "XGMII_WS",
99 	[LOOPBACK_XAUI_WS]	= "XAUI_WS",
100 	[LOOPBACK_XAUI_WS_FAR]  = "XAUI_WS_FAR",
101 	[LOOPBACK_XAUI_WS_NEAR] = "XAUI_WS_NEAR",
102 	[LOOPBACK_GMII_WS]	= "GMII_WS",
103 	[LOOPBACK_XFI_WS]	= "XFI_WS",
104 	[LOOPBACK_XFI_WS_FAR]	= "XFI_WS_FAR",
105 	[LOOPBACK_PHYXS_WS]	= "PHYXS_WS",
106 };
107 
108 /* Reset workqueue. If any NIC has a hardware failure then a reset will be
109  * queued onto this work queue. This is not a per-nic work queue, because
110  * efx_reset_work() acquires the rtnl lock, so resets are naturally serialised.
111  */
112 static struct workqueue_struct *reset_workqueue;
113 
114 int efx_create_reset_workqueue(void)
115 {
116 	reset_workqueue = create_singlethread_workqueue("sfc_reset");
117 	if (!reset_workqueue) {
118 		printk(KERN_ERR "Failed to create reset workqueue\n");
119 		return -ENOMEM;
120 	}
121 
122 	return 0;
123 }
124 
125 void efx_queue_reset_work(struct efx_nic *efx)
126 {
127 	queue_work(reset_workqueue, &efx->reset_work);
128 }
129 
130 void efx_flush_reset_workqueue(struct efx_nic *efx)
131 {
132 	cancel_work_sync(&efx->reset_work);
133 }
134 
135 void efx_destroy_reset_workqueue(void)
136 {
137 	if (reset_workqueue) {
138 		destroy_workqueue(reset_workqueue);
139 		reset_workqueue = NULL;
140 	}
141 }
142 
143 /* We assume that efx->type->reconfigure_mac will always try to sync RX
144  * filters and therefore needs to read-lock the filter table against freeing
145  */
146 void efx_mac_reconfigure(struct efx_nic *efx, bool mtu_only)
147 {
148 	if (efx->type->reconfigure_mac) {
149 		down_read(&efx->filter_sem);
150 		efx->type->reconfigure_mac(efx, mtu_only);
151 		up_read(&efx->filter_sem);
152 	}
153 }
154 
155 /* Asynchronous work item for changing MAC promiscuity and multicast
156  * hash.  Avoid a drain/rx_ingress enable by reconfiguring the current
157  * MAC directly.
158  */
159 static void efx_mac_work(struct work_struct *data)
160 {
161 	struct efx_nic *efx = container_of(data, struct efx_nic, mac_work);
162 
163 	mutex_lock(&efx->mac_lock);
164 	if (efx->port_enabled)
165 		efx_mac_reconfigure(efx, false);
166 	mutex_unlock(&efx->mac_lock);
167 }
168 
169 int efx_set_mac_address(struct net_device *net_dev, void *data)
170 {
171 	struct efx_nic *efx = efx_netdev_priv(net_dev);
172 	struct sockaddr *addr = data;
173 	u8 *new_addr = addr->sa_data;
174 	u8 old_addr[6];
175 	int rc;
176 
177 	if (!is_valid_ether_addr(new_addr)) {
178 		netif_err(efx, drv, efx->net_dev,
179 			  "invalid ethernet MAC address requested: %pM\n",
180 			  new_addr);
181 		return -EADDRNOTAVAIL;
182 	}
183 
184 	/* save old address */
185 	ether_addr_copy(old_addr, net_dev->dev_addr);
186 	eth_hw_addr_set(net_dev, new_addr);
187 	if (efx->type->set_mac_address) {
188 		rc = efx->type->set_mac_address(efx);
189 		if (rc) {
190 			eth_hw_addr_set(net_dev, old_addr);
191 			return rc;
192 		}
193 	}
194 
195 	/* Reconfigure the MAC */
196 	mutex_lock(&efx->mac_lock);
197 	efx_mac_reconfigure(efx, false);
198 	mutex_unlock(&efx->mac_lock);
199 
200 	return 0;
201 }
202 
203 /* Context: netif_addr_lock held, BHs disabled. */
204 void efx_set_rx_mode(struct net_device *net_dev)
205 {
206 	struct efx_nic *efx = efx_netdev_priv(net_dev);
207 
208 	if (efx->port_enabled)
209 		queue_work(efx->workqueue, &efx->mac_work);
210 	/* Otherwise efx_start_port() will do this */
211 }
212 
213 int efx_set_features(struct net_device *net_dev, netdev_features_t data)
214 {
215 	struct efx_nic *efx = efx_netdev_priv(net_dev);
216 	int rc;
217 
218 	/* If disabling RX n-tuple filtering, clear existing filters */
219 	if (net_dev->features & ~data & NETIF_F_NTUPLE) {
220 		rc = efx->type->filter_clear_rx(efx, EFX_FILTER_PRI_MANUAL);
221 		if (rc)
222 			return rc;
223 	}
224 
225 	/* If Rx VLAN filter is changed, update filters via mac_reconfigure.
226 	 * If rx-fcs is changed, mac_reconfigure updates that too.
227 	 */
228 	if ((net_dev->features ^ data) & (NETIF_F_HW_VLAN_CTAG_FILTER |
229 					  NETIF_F_RXFCS)) {
230 		/* efx_set_rx_mode() will schedule MAC work to update filters
231 		 * when a new features are finally set in net_dev.
232 		 */
233 		efx_set_rx_mode(net_dev);
234 	}
235 
236 	return 0;
237 }
238 
239 /* This ensures that the kernel is kept informed (via
240  * netif_carrier_on/off) of the link status, and also maintains the
241  * link status's stop on the port's TX queue.
242  */
243 void efx_link_status_changed(struct efx_nic *efx)
244 {
245 	struct efx_link_state *link_state = &efx->link_state;
246 
247 	/* SFC Bug 5356: A net_dev notifier is registered, so we must ensure
248 	 * that no events are triggered between unregister_netdev() and the
249 	 * driver unloading. A more general condition is that NETDEV_CHANGE
250 	 * can only be generated between NETDEV_UP and NETDEV_DOWN
251 	 */
252 	if (!netif_running(efx->net_dev))
253 		return;
254 
255 	if (link_state->up != netif_carrier_ok(efx->net_dev)) {
256 		efx->n_link_state_changes++;
257 
258 		if (link_state->up)
259 			netif_carrier_on(efx->net_dev);
260 		else
261 			netif_carrier_off(efx->net_dev);
262 	}
263 
264 	/* Status message for kernel log */
265 	if (link_state->up)
266 		netif_info(efx, link, efx->net_dev,
267 			   "link up at %uMbps %s-duplex (MTU %d)\n",
268 			   link_state->speed, link_state->fd ? "full" : "half",
269 			   efx->net_dev->mtu);
270 	else
271 		netif_info(efx, link, efx->net_dev, "link down\n");
272 }
273 
274 unsigned int efx_xdp_max_mtu(struct efx_nic *efx)
275 {
276 	/* The maximum MTU that we can fit in a single page, allowing for
277 	 * framing, overhead and XDP headroom + tailroom.
278 	 */
279 	int overhead = EFX_MAX_FRAME_LEN(0) + sizeof(struct efx_rx_page_state) +
280 		       efx->rx_prefix_size + efx->type->rx_buffer_padding +
281 		       efx->rx_ip_align + EFX_XDP_HEADROOM + EFX_XDP_TAILROOM;
282 
283 	return PAGE_SIZE - overhead;
284 }
285 
286 /* Context: process, rtnl_lock() held. */
287 int efx_change_mtu(struct net_device *net_dev, int new_mtu)
288 {
289 	struct efx_nic *efx = efx_netdev_priv(net_dev);
290 	int rc;
291 
292 	rc = efx_check_disabled(efx);
293 	if (rc)
294 		return rc;
295 
296 	if (rtnl_dereference(efx->xdp_prog) &&
297 	    new_mtu > efx_xdp_max_mtu(efx)) {
298 		netif_err(efx, drv, efx->net_dev,
299 			  "Requested MTU of %d too big for XDP (max: %d)\n",
300 			  new_mtu, efx_xdp_max_mtu(efx));
301 		return -EINVAL;
302 	}
303 
304 	netif_dbg(efx, drv, efx->net_dev, "changing MTU to %d\n", new_mtu);
305 
306 	efx_device_detach_sync(efx);
307 	efx_stop_all(efx);
308 
309 	mutex_lock(&efx->mac_lock);
310 	net_dev->mtu = new_mtu;
311 	efx_mac_reconfigure(efx, true);
312 	mutex_unlock(&efx->mac_lock);
313 
314 	efx_start_all(efx);
315 	efx_device_attach_if_not_resetting(efx);
316 	return 0;
317 }
318 
319 /**************************************************************************
320  *
321  * Hardware monitor
322  *
323  **************************************************************************/
324 
325 /* Run periodically off the general workqueue */
326 static void efx_monitor(struct work_struct *data)
327 {
328 	struct efx_nic *efx = container_of(data, struct efx_nic,
329 					   monitor_work.work);
330 
331 	netif_vdbg(efx, timer, efx->net_dev,
332 		   "hardware monitor executing on CPU %d\n",
333 		   raw_smp_processor_id());
334 	BUG_ON(efx->type->monitor == NULL);
335 
336 	/* If the mac_lock is already held then it is likely a port
337 	 * reconfiguration is already in place, which will likely do
338 	 * most of the work of monitor() anyway.
339 	 */
340 	if (mutex_trylock(&efx->mac_lock)) {
341 		if (efx->port_enabled && efx->type->monitor)
342 			efx->type->monitor(efx);
343 		mutex_unlock(&efx->mac_lock);
344 	}
345 
346 	efx_start_monitor(efx);
347 }
348 
349 void efx_start_monitor(struct efx_nic *efx)
350 {
351 	if (efx->type->monitor)
352 		queue_delayed_work(efx->workqueue, &efx->monitor_work,
353 				   efx_monitor_interval);
354 }
355 
356 /**************************************************************************
357  *
358  * Event queue processing
359  *
360  *************************************************************************/
361 
362 /* Channels are shutdown and reinitialised whilst the NIC is running
363  * to propagate configuration changes (mtu, checksum offload), or
364  * to clear hardware error conditions
365  */
366 static void efx_start_datapath(struct efx_nic *efx)
367 {
368 	netdev_features_t old_features = efx->net_dev->features;
369 	bool old_rx_scatter = efx->rx_scatter;
370 	size_t rx_buf_len;
371 
372 	/* Calculate the rx buffer allocation parameters required to
373 	 * support the current MTU, including padding for header
374 	 * alignment and overruns.
375 	 */
376 	efx->rx_dma_len = (efx->rx_prefix_size +
377 			   EFX_MAX_FRAME_LEN(efx->net_dev->mtu) +
378 			   efx->type->rx_buffer_padding);
379 	rx_buf_len = (sizeof(struct efx_rx_page_state)   + EFX_XDP_HEADROOM +
380 		      efx->rx_ip_align + efx->rx_dma_len + EFX_XDP_TAILROOM);
381 
382 	if (rx_buf_len <= PAGE_SIZE) {
383 		efx->rx_scatter = efx->type->always_rx_scatter;
384 		efx->rx_buffer_order = 0;
385 	} else if (efx->type->can_rx_scatter) {
386 		BUILD_BUG_ON(EFX_RX_USR_BUF_SIZE % L1_CACHE_BYTES);
387 		BUILD_BUG_ON(sizeof(struct efx_rx_page_state) +
388 			     2 * ALIGN(NET_IP_ALIGN + EFX_RX_USR_BUF_SIZE,
389 				       EFX_RX_BUF_ALIGNMENT) >
390 			     PAGE_SIZE);
391 		efx->rx_scatter = true;
392 		efx->rx_dma_len = EFX_RX_USR_BUF_SIZE;
393 		efx->rx_buffer_order = 0;
394 	} else {
395 		efx->rx_scatter = false;
396 		efx->rx_buffer_order = get_order(rx_buf_len);
397 	}
398 
399 	efx_rx_config_page_split(efx);
400 	if (efx->rx_buffer_order)
401 		netif_dbg(efx, drv, efx->net_dev,
402 			  "RX buf len=%u; page order=%u batch=%u\n",
403 			  efx->rx_dma_len, efx->rx_buffer_order,
404 			  efx->rx_pages_per_batch);
405 	else
406 		netif_dbg(efx, drv, efx->net_dev,
407 			  "RX buf len=%u step=%u bpp=%u; page batch=%u\n",
408 			  efx->rx_dma_len, efx->rx_page_buf_step,
409 			  efx->rx_bufs_per_page, efx->rx_pages_per_batch);
410 
411 	/* Restore previously fixed features in hw_features and remove
412 	 * features which are fixed now
413 	 */
414 	efx->net_dev->hw_features |= efx->net_dev->features;
415 	efx->net_dev->hw_features &= ~efx->fixed_features;
416 	efx->net_dev->features |= efx->fixed_features;
417 	if (efx->net_dev->features != old_features)
418 		netdev_features_change(efx->net_dev);
419 
420 	/* RX filters may also have scatter-enabled flags */
421 	if ((efx->rx_scatter != old_rx_scatter) &&
422 	    efx->type->filter_update_rx_scatter)
423 		efx->type->filter_update_rx_scatter(efx);
424 
425 	/* We must keep at least one descriptor in a TX ring empty.
426 	 * We could avoid this when the queue size does not exactly
427 	 * match the hardware ring size, but it's not that important.
428 	 * Therefore we stop the queue when one more skb might fill
429 	 * the ring completely.  We wake it when half way back to
430 	 * empty.
431 	 */
432 	efx->txq_stop_thresh = efx->txq_entries - efx_tx_max_skb_descs(efx);
433 	efx->txq_wake_thresh = efx->txq_stop_thresh / 2;
434 
435 	/* Initialise the channels */
436 	efx_start_channels(efx);
437 
438 	efx_ptp_start_datapath(efx);
439 
440 	if (netif_device_present(efx->net_dev))
441 		netif_tx_wake_all_queues(efx->net_dev);
442 }
443 
444 static void efx_stop_datapath(struct efx_nic *efx)
445 {
446 	EFX_ASSERT_RESET_SERIALISED(efx);
447 	BUG_ON(efx->port_enabled);
448 
449 	efx_ptp_stop_datapath(efx);
450 
451 	efx_stop_channels(efx);
452 }
453 
454 /**************************************************************************
455  *
456  * Port handling
457  *
458  **************************************************************************/
459 
460 /* Equivalent to efx_link_set_advertising with all-zeroes, except does not
461  * force the Autoneg bit on.
462  */
463 void efx_link_clear_advertising(struct efx_nic *efx)
464 {
465 	bitmap_zero(efx->link_advertising, __ETHTOOL_LINK_MODE_MASK_NBITS);
466 	efx->wanted_fc &= ~(EFX_FC_TX | EFX_FC_RX);
467 }
468 
469 void efx_link_set_wanted_fc(struct efx_nic *efx, u8 wanted_fc)
470 {
471 	efx->wanted_fc = wanted_fc;
472 	if (efx->link_advertising[0]) {
473 		if (wanted_fc & EFX_FC_RX)
474 			efx->link_advertising[0] |= (ADVERTISED_Pause |
475 						     ADVERTISED_Asym_Pause);
476 		else
477 			efx->link_advertising[0] &= ~(ADVERTISED_Pause |
478 						      ADVERTISED_Asym_Pause);
479 		if (wanted_fc & EFX_FC_TX)
480 			efx->link_advertising[0] ^= ADVERTISED_Asym_Pause;
481 	}
482 }
483 
484 static void efx_start_port(struct efx_nic *efx)
485 {
486 	netif_dbg(efx, ifup, efx->net_dev, "start port\n");
487 	BUG_ON(efx->port_enabled);
488 
489 	mutex_lock(&efx->mac_lock);
490 	efx->port_enabled = true;
491 
492 	/* Ensure MAC ingress/egress is enabled */
493 	efx_mac_reconfigure(efx, false);
494 
495 	mutex_unlock(&efx->mac_lock);
496 }
497 
498 /* Cancel work for MAC reconfiguration, periodic hardware monitoring
499  * and the async self-test, wait for them to finish and prevent them
500  * being scheduled again.  This doesn't cover online resets, which
501  * should only be cancelled when removing the device.
502  */
503 static void efx_stop_port(struct efx_nic *efx)
504 {
505 	netif_dbg(efx, ifdown, efx->net_dev, "stop port\n");
506 
507 	EFX_ASSERT_RESET_SERIALISED(efx);
508 
509 	mutex_lock(&efx->mac_lock);
510 	efx->port_enabled = false;
511 	mutex_unlock(&efx->mac_lock);
512 
513 	/* Serialise against efx_set_multicast_list() */
514 	netif_addr_lock_bh(efx->net_dev);
515 	netif_addr_unlock_bh(efx->net_dev);
516 
517 	cancel_delayed_work_sync(&efx->monitor_work);
518 	efx_selftest_async_cancel(efx);
519 	cancel_work_sync(&efx->mac_work);
520 }
521 
522 /* If the interface is supposed to be running but is not, start
523  * the hardware and software data path, regular activity for the port
524  * (MAC statistics, link polling, etc.) and schedule the port to be
525  * reconfigured.  Interrupts must already be enabled.  This function
526  * is safe to call multiple times, so long as the NIC is not disabled.
527  * Requires the RTNL lock.
528  */
529 void efx_start_all(struct efx_nic *efx)
530 {
531 	EFX_ASSERT_RESET_SERIALISED(efx);
532 	BUG_ON(efx->state == STATE_DISABLED);
533 
534 	/* Check that it is appropriate to restart the interface. All
535 	 * of these flags are safe to read under just the rtnl lock
536 	 */
537 	if (efx->port_enabled || !netif_running(efx->net_dev) ||
538 	    efx->reset_pending)
539 		return;
540 
541 	efx_start_port(efx);
542 	efx_start_datapath(efx);
543 
544 	/* Start the hardware monitor if there is one */
545 	efx_start_monitor(efx);
546 
547 	/* Link state detection is normally event-driven; we have
548 	 * to poll now because we could have missed a change
549 	 */
550 	mutex_lock(&efx->mac_lock);
551 	if (efx_mcdi_phy_poll(efx))
552 		efx_link_status_changed(efx);
553 	mutex_unlock(&efx->mac_lock);
554 
555 	if (efx->type->start_stats) {
556 		efx->type->start_stats(efx);
557 		efx->type->pull_stats(efx);
558 		spin_lock_bh(&efx->stats_lock);
559 		efx->type->update_stats(efx, NULL, NULL);
560 		spin_unlock_bh(&efx->stats_lock);
561 	}
562 }
563 
564 /* Quiesce the hardware and software data path, and regular activity
565  * for the port without bringing the link down.  Safe to call multiple
566  * times with the NIC in almost any state, but interrupts should be
567  * enabled.  Requires the RTNL lock.
568  */
569 void efx_stop_all(struct efx_nic *efx)
570 {
571 	EFX_ASSERT_RESET_SERIALISED(efx);
572 
573 	/* port_enabled can be read safely under the rtnl lock */
574 	if (!efx->port_enabled)
575 		return;
576 
577 	if (efx->type->update_stats) {
578 		/* update stats before we go down so we can accurately count
579 		 * rx_nodesc_drops
580 		 */
581 		efx->type->pull_stats(efx);
582 		spin_lock_bh(&efx->stats_lock);
583 		efx->type->update_stats(efx, NULL, NULL);
584 		spin_unlock_bh(&efx->stats_lock);
585 		efx->type->stop_stats(efx);
586 	}
587 
588 	efx_stop_port(efx);
589 
590 	/* Stop the kernel transmit interface.  This is only valid if
591 	 * the device is stopped or detached; otherwise the watchdog
592 	 * may fire immediately.
593 	 */
594 	WARN_ON(netif_running(efx->net_dev) &&
595 		netif_device_present(efx->net_dev));
596 	netif_tx_disable(efx->net_dev);
597 
598 	efx_stop_datapath(efx);
599 }
600 
601 /* Context: process, dev_base_lock or RTNL held, non-blocking. */
602 void efx_net_stats(struct net_device *net_dev, struct rtnl_link_stats64 *stats)
603 {
604 	struct efx_nic *efx = efx_netdev_priv(net_dev);
605 
606 	spin_lock_bh(&efx->stats_lock);
607 	efx_nic_update_stats_atomic(efx, NULL, stats);
608 	spin_unlock_bh(&efx->stats_lock);
609 }
610 
611 /* Push loopback/power/transmit disable settings to the PHY, and reconfigure
612  * the MAC appropriately. All other PHY configuration changes are pushed
613  * through phy_op->set_settings(), and pushed asynchronously to the MAC
614  * through efx_monitor().
615  *
616  * Callers must hold the mac_lock
617  */
618 int __efx_reconfigure_port(struct efx_nic *efx)
619 {
620 	enum efx_phy_mode phy_mode;
621 	int rc = 0;
622 
623 	WARN_ON(!mutex_is_locked(&efx->mac_lock));
624 
625 	/* Disable PHY transmit in mac level loopbacks */
626 	phy_mode = efx->phy_mode;
627 	if (LOOPBACK_INTERNAL(efx))
628 		efx->phy_mode |= PHY_MODE_TX_DISABLED;
629 	else
630 		efx->phy_mode &= ~PHY_MODE_TX_DISABLED;
631 
632 	if (efx->type->reconfigure_port)
633 		rc = efx->type->reconfigure_port(efx);
634 
635 	if (rc)
636 		efx->phy_mode = phy_mode;
637 
638 	return rc;
639 }
640 
641 /* Reinitialise the MAC to pick up new PHY settings, even if the port is
642  * disabled.
643  */
644 int efx_reconfigure_port(struct efx_nic *efx)
645 {
646 	int rc;
647 
648 	EFX_ASSERT_RESET_SERIALISED(efx);
649 
650 	mutex_lock(&efx->mac_lock);
651 	rc = __efx_reconfigure_port(efx);
652 	mutex_unlock(&efx->mac_lock);
653 
654 	return rc;
655 }
656 
657 /**************************************************************************
658  *
659  * Device reset and suspend
660  *
661  **************************************************************************/
662 
663 static void efx_wait_for_bist_end(struct efx_nic *efx)
664 {
665 	int i;
666 
667 	for (i = 0; i < BIST_WAIT_DELAY_COUNT; ++i) {
668 		if (efx_mcdi_poll_reboot(efx))
669 			goto out;
670 		msleep(BIST_WAIT_DELAY_MS);
671 	}
672 
673 	netif_err(efx, drv, efx->net_dev, "Warning: No MC reboot after BIST mode\n");
674 out:
675 	/* Either way unset the BIST flag. If we found no reboot we probably
676 	 * won't recover, but we should try.
677 	 */
678 	efx->mc_bist_for_other_fn = false;
679 }
680 
681 /* Try recovery mechanisms.
682  * For now only EEH is supported.
683  * Returns 0 if the recovery mechanisms are unsuccessful.
684  * Returns a non-zero value otherwise.
685  */
686 int efx_try_recovery(struct efx_nic *efx)
687 {
688 #ifdef CONFIG_EEH
689 	/* A PCI error can occur and not be seen by EEH because nothing
690 	 * happens on the PCI bus. In this case the driver may fail and
691 	 * schedule a 'recover or reset', leading to this recovery handler.
692 	 * Manually call the eeh failure check function.
693 	 */
694 	struct eeh_dev *eehdev = pci_dev_to_eeh_dev(efx->pci_dev);
695 	if (eeh_dev_check_failure(eehdev)) {
696 		/* The EEH mechanisms will handle the error and reset the
697 		 * device if necessary.
698 		 */
699 		return 1;
700 	}
701 #endif
702 	return 0;
703 }
704 
705 /* Tears down the entire software state and most of the hardware state
706  * before reset.
707  */
708 void efx_reset_down(struct efx_nic *efx, enum reset_type method)
709 {
710 	EFX_ASSERT_RESET_SERIALISED(efx);
711 
712 	if (method == RESET_TYPE_MCDI_TIMEOUT)
713 		efx->type->prepare_flr(efx);
714 
715 	efx_stop_all(efx);
716 	efx_disable_interrupts(efx);
717 
718 	mutex_lock(&efx->mac_lock);
719 	down_write(&efx->filter_sem);
720 	mutex_lock(&efx->rss_lock);
721 	efx->type->fini(efx);
722 }
723 
724 /* Context: netif_tx_lock held, BHs disabled. */
725 void efx_watchdog(struct net_device *net_dev, unsigned int txqueue)
726 {
727 	struct efx_nic *efx = efx_netdev_priv(net_dev);
728 
729 	netif_err(efx, tx_err, efx->net_dev,
730 		  "TX stuck with port_enabled=%d: resetting channels\n",
731 		  efx->port_enabled);
732 
733 	efx_schedule_reset(efx, RESET_TYPE_TX_WATCHDOG);
734 }
735 
736 /* This function will always ensure that the locks acquired in
737  * efx_reset_down() are released. A failure return code indicates
738  * that we were unable to reinitialise the hardware, and the
739  * driver should be disabled. If ok is false, then the rx and tx
740  * engines are not restarted, pending a RESET_DISABLE.
741  */
742 int efx_reset_up(struct efx_nic *efx, enum reset_type method, bool ok)
743 {
744 	int rc;
745 
746 	EFX_ASSERT_RESET_SERIALISED(efx);
747 
748 	if (method == RESET_TYPE_MCDI_TIMEOUT)
749 		efx->type->finish_flr(efx);
750 
751 	/* Ensure that SRAM is initialised even if we're disabling the device */
752 	rc = efx->type->init(efx);
753 	if (rc) {
754 		netif_err(efx, drv, efx->net_dev, "failed to initialise NIC\n");
755 		goto fail;
756 	}
757 
758 	if (!ok)
759 		goto fail;
760 
761 	if (efx->port_initialized && method != RESET_TYPE_INVISIBLE &&
762 	    method != RESET_TYPE_DATAPATH) {
763 		rc = efx_mcdi_port_reconfigure(efx);
764 		if (rc && rc != -EPERM)
765 			netif_err(efx, drv, efx->net_dev,
766 				  "could not restore PHY settings\n");
767 	}
768 
769 	rc = efx_enable_interrupts(efx);
770 	if (rc)
771 		goto fail;
772 
773 #ifdef CONFIG_SFC_SRIOV
774 	rc = efx->type->vswitching_restore(efx);
775 	if (rc) /* not fatal; the PF will still work fine */
776 		netif_warn(efx, probe, efx->net_dev,
777 			   "failed to restore vswitching rc=%d;"
778 			   " VFs may not function\n", rc);
779 #endif
780 
781 	if (efx->type->rx_restore_rss_contexts)
782 		efx->type->rx_restore_rss_contexts(efx);
783 	mutex_unlock(&efx->rss_lock);
784 	efx->type->filter_table_restore(efx);
785 	up_write(&efx->filter_sem);
786 	if (efx->type->sriov_reset)
787 		efx->type->sriov_reset(efx);
788 
789 	mutex_unlock(&efx->mac_lock);
790 
791 	efx_start_all(efx);
792 
793 	if (efx->type->udp_tnl_push_ports)
794 		efx->type->udp_tnl_push_ports(efx);
795 
796 	return 0;
797 
798 fail:
799 	efx->port_initialized = false;
800 
801 	mutex_unlock(&efx->rss_lock);
802 	up_write(&efx->filter_sem);
803 	mutex_unlock(&efx->mac_lock);
804 
805 	return rc;
806 }
807 
808 /* Reset the NIC using the specified method.  Note that the reset may
809  * fail, in which case the card will be left in an unusable state.
810  *
811  * Caller must hold the rtnl_lock.
812  */
813 int efx_reset(struct efx_nic *efx, enum reset_type method)
814 {
815 	int rc, rc2 = 0;
816 	bool disabled;
817 
818 	netif_info(efx, drv, efx->net_dev, "resetting (%s)\n",
819 		   RESET_TYPE(method));
820 
821 	efx_device_detach_sync(efx);
822 	/* efx_reset_down() grabs locks that prevent recovery on EF100.
823 	 * EF100 reset is handled in the efx_nic_type callback below.
824 	 */
825 	if (efx_nic_rev(efx) != EFX_REV_EF100)
826 		efx_reset_down(efx, method);
827 
828 	rc = efx->type->reset(efx, method);
829 	if (rc) {
830 		netif_err(efx, drv, efx->net_dev, "failed to reset hardware\n");
831 		goto out;
832 	}
833 
834 	/* Clear flags for the scopes we covered.  We assume the NIC and
835 	 * driver are now quiescent so that there is no race here.
836 	 */
837 	if (method < RESET_TYPE_MAX_METHOD)
838 		efx->reset_pending &= -(1 << (method + 1));
839 	else /* it doesn't fit into the well-ordered scope hierarchy */
840 		__clear_bit(method, &efx->reset_pending);
841 
842 	/* Reinitialise bus-mastering, which may have been turned off before
843 	 * the reset was scheduled. This is still appropriate, even in the
844 	 * RESET_TYPE_DISABLE since this driver generally assumes the hardware
845 	 * can respond to requests.
846 	 */
847 	pci_set_master(efx->pci_dev);
848 
849 out:
850 	/* Leave device stopped if necessary */
851 	disabled = rc ||
852 		method == RESET_TYPE_DISABLE ||
853 		method == RESET_TYPE_RECOVER_OR_DISABLE;
854 	if (efx_nic_rev(efx) != EFX_REV_EF100)
855 		rc2 = efx_reset_up(efx, method, !disabled);
856 	if (rc2) {
857 		disabled = true;
858 		if (!rc)
859 			rc = rc2;
860 	}
861 
862 	if (disabled) {
863 		dev_close(efx->net_dev);
864 		netif_err(efx, drv, efx->net_dev, "has been disabled\n");
865 		efx->state = STATE_DISABLED;
866 	} else {
867 		netif_dbg(efx, drv, efx->net_dev, "reset complete\n");
868 		efx_device_attach_if_not_resetting(efx);
869 	}
870 	return rc;
871 }
872 
873 /* The worker thread exists so that code that cannot sleep can
874  * schedule a reset for later.
875  */
876 static void efx_reset_work(struct work_struct *data)
877 {
878 	struct efx_nic *efx = container_of(data, struct efx_nic, reset_work);
879 	unsigned long pending;
880 	enum reset_type method;
881 
882 	pending = READ_ONCE(efx->reset_pending);
883 	method = fls(pending) - 1;
884 
885 	if (method == RESET_TYPE_MC_BIST)
886 		efx_wait_for_bist_end(efx);
887 
888 	if ((method == RESET_TYPE_RECOVER_OR_DISABLE ||
889 	     method == RESET_TYPE_RECOVER_OR_ALL) &&
890 	    efx_try_recovery(efx))
891 		return;
892 
893 	if (!pending)
894 		return;
895 
896 	rtnl_lock();
897 
898 	/* We checked the state in efx_schedule_reset() but it may
899 	 * have changed by now.  Now that we have the RTNL lock,
900 	 * it cannot change again.
901 	 */
902 	if (efx_net_active(efx->state))
903 		(void)efx_reset(efx, method);
904 
905 	rtnl_unlock();
906 }
907 
908 void efx_schedule_reset(struct efx_nic *efx, enum reset_type type)
909 {
910 	enum reset_type method;
911 
912 	if (efx_recovering(efx->state)) {
913 		netif_dbg(efx, drv, efx->net_dev,
914 			  "recovering: skip scheduling %s reset\n",
915 			  RESET_TYPE(type));
916 		return;
917 	}
918 
919 	switch (type) {
920 	case RESET_TYPE_INVISIBLE:
921 	case RESET_TYPE_ALL:
922 	case RESET_TYPE_RECOVER_OR_ALL:
923 	case RESET_TYPE_WORLD:
924 	case RESET_TYPE_DISABLE:
925 	case RESET_TYPE_RECOVER_OR_DISABLE:
926 	case RESET_TYPE_DATAPATH:
927 	case RESET_TYPE_MC_BIST:
928 	case RESET_TYPE_MCDI_TIMEOUT:
929 		method = type;
930 		netif_dbg(efx, drv, efx->net_dev, "scheduling %s reset\n",
931 			  RESET_TYPE(method));
932 		break;
933 	default:
934 		method = efx->type->map_reset_reason(type);
935 		netif_dbg(efx, drv, efx->net_dev,
936 			  "scheduling %s reset for %s\n",
937 			  RESET_TYPE(method), RESET_TYPE(type));
938 		break;
939 	}
940 
941 	set_bit(method, &efx->reset_pending);
942 	smp_mb(); /* ensure we change reset_pending before checking state */
943 
944 	/* If we're not READY then just leave the flags set as the cue
945 	 * to abort probing or reschedule the reset later.
946 	 */
947 	if (!efx_net_active(READ_ONCE(efx->state)))
948 		return;
949 
950 	/* efx_process_channel() will no longer read events once a
951 	 * reset is scheduled. So switch back to poll'd MCDI completions.
952 	 */
953 	efx_mcdi_mode_poll(efx);
954 
955 	efx_queue_reset_work(efx);
956 }
957 
958 /**************************************************************************
959  *
960  * Dummy NIC operations
961  *
962  * Can be used for some unimplemented operations
963  * Needed so all function pointers are valid and do not have to be tested
964  * before use
965  *
966  **************************************************************************/
967 int efx_port_dummy_op_int(struct efx_nic *efx)
968 {
969 	return 0;
970 }
971 void efx_port_dummy_op_void(struct efx_nic *efx) {}
972 
973 /**************************************************************************
974  *
975  * Data housekeeping
976  *
977  **************************************************************************/
978 
979 /* This zeroes out and then fills in the invariants in a struct
980  * efx_nic (including all sub-structures).
981  */
982 int efx_init_struct(struct efx_nic *efx, struct pci_dev *pci_dev)
983 {
984 	int rc = -ENOMEM;
985 
986 	/* Initialise common structures */
987 	INIT_LIST_HEAD(&efx->node);
988 	INIT_LIST_HEAD(&efx->secondary_list);
989 	spin_lock_init(&efx->biu_lock);
990 #ifdef CONFIG_SFC_MTD
991 	INIT_LIST_HEAD(&efx->mtd_list);
992 #endif
993 	INIT_WORK(&efx->reset_work, efx_reset_work);
994 	INIT_DELAYED_WORK(&efx->monitor_work, efx_monitor);
995 	efx_selftest_async_init(efx);
996 	efx->pci_dev = pci_dev;
997 	efx->msg_enable = debug;
998 	efx->state = STATE_UNINIT;
999 	strscpy(efx->name, pci_name(pci_dev), sizeof(efx->name));
1000 
1001 	efx->rx_prefix_size = efx->type->rx_prefix_size;
1002 	efx->rx_ip_align =
1003 		NET_IP_ALIGN ? (efx->rx_prefix_size + NET_IP_ALIGN) % 4 : 0;
1004 	efx->rx_packet_hash_offset =
1005 		efx->type->rx_hash_offset - efx->type->rx_prefix_size;
1006 	efx->rx_packet_ts_offset =
1007 		efx->type->rx_ts_offset - efx->type->rx_prefix_size;
1008 	INIT_LIST_HEAD(&efx->rss_context.list);
1009 	efx->rss_context.context_id = EFX_MCDI_RSS_CONTEXT_INVALID;
1010 	mutex_init(&efx->rss_lock);
1011 	efx->vport_id = EVB_PORT_ID_ASSIGNED;
1012 	spin_lock_init(&efx->stats_lock);
1013 	efx->vi_stride = EFX_DEFAULT_VI_STRIDE;
1014 	efx->num_mac_stats = MC_CMD_MAC_NSTATS;
1015 	BUILD_BUG_ON(MC_CMD_MAC_NSTATS - 1 != MC_CMD_MAC_GENERATION_END);
1016 	mutex_init(&efx->mac_lock);
1017 	init_rwsem(&efx->filter_sem);
1018 #ifdef CONFIG_RFS_ACCEL
1019 	mutex_init(&efx->rps_mutex);
1020 	spin_lock_init(&efx->rps_hash_lock);
1021 	/* Failure to allocate is not fatal, but may degrade ARFS performance */
1022 	efx->rps_hash_table = kcalloc(EFX_ARFS_HASH_TABLE_SIZE,
1023 				      sizeof(*efx->rps_hash_table), GFP_KERNEL);
1024 #endif
1025 	spin_lock_init(&efx->vf_reps_lock);
1026 	INIT_LIST_HEAD(&efx->vf_reps);
1027 	INIT_WORK(&efx->mac_work, efx_mac_work);
1028 	init_waitqueue_head(&efx->flush_wq);
1029 
1030 	efx->tx_queues_per_channel = 1;
1031 	efx->rxq_entries = EFX_DEFAULT_DMAQ_SIZE;
1032 	efx->txq_entries = EFX_DEFAULT_DMAQ_SIZE;
1033 
1034 	efx->mem_bar = UINT_MAX;
1035 
1036 	rc = efx_init_channels(efx);
1037 	if (rc)
1038 		goto fail;
1039 
1040 	/* Would be good to use the net_dev name, but we're too early */
1041 	snprintf(efx->workqueue_name, sizeof(efx->workqueue_name), "sfc%s",
1042 		 pci_name(pci_dev));
1043 	efx->workqueue = create_singlethread_workqueue(efx->workqueue_name);
1044 	if (!efx->workqueue) {
1045 		rc = -ENOMEM;
1046 		goto fail;
1047 	}
1048 
1049 	return 0;
1050 
1051 fail:
1052 	efx_fini_struct(efx);
1053 	return rc;
1054 }
1055 
1056 void efx_fini_struct(struct efx_nic *efx)
1057 {
1058 #ifdef CONFIG_RFS_ACCEL
1059 	kfree(efx->rps_hash_table);
1060 #endif
1061 
1062 	efx_fini_channels(efx);
1063 
1064 	kfree(efx->vpd_sn);
1065 
1066 	if (efx->workqueue) {
1067 		destroy_workqueue(efx->workqueue);
1068 		efx->workqueue = NULL;
1069 	}
1070 }
1071 
1072 /* This configures the PCI device to enable I/O and DMA. */
1073 int efx_init_io(struct efx_nic *efx, int bar, dma_addr_t dma_mask,
1074 		unsigned int mem_map_size)
1075 {
1076 	struct pci_dev *pci_dev = efx->pci_dev;
1077 	int rc;
1078 
1079 	efx->mem_bar = UINT_MAX;
1080 	pci_dbg(pci_dev, "initialising I/O bar=%d\n", bar);
1081 
1082 	rc = pci_enable_device(pci_dev);
1083 	if (rc) {
1084 		pci_err(pci_dev, "failed to enable PCI device\n");
1085 		goto fail1;
1086 	}
1087 
1088 	pci_set_master(pci_dev);
1089 
1090 	rc = dma_set_mask_and_coherent(&pci_dev->dev, dma_mask);
1091 	if (rc) {
1092 		pci_err(efx->pci_dev, "could not find a suitable DMA mask\n");
1093 		goto fail2;
1094 	}
1095 	pci_dbg(efx->pci_dev, "using DMA mask %llx\n", (unsigned long long)dma_mask);
1096 
1097 	efx->membase_phys = pci_resource_start(efx->pci_dev, bar);
1098 	if (!efx->membase_phys) {
1099 		pci_err(efx->pci_dev,
1100 			"ERROR: No BAR%d mapping from the BIOS. Try pci=realloc on the kernel command line\n",
1101 			bar);
1102 		rc = -ENODEV;
1103 		goto fail3;
1104 	}
1105 
1106 	rc = pci_request_region(pci_dev, bar, "sfc");
1107 	if (rc) {
1108 		pci_err(efx->pci_dev,
1109 			"request for memory BAR[%d] failed\n", bar);
1110 		rc = -EIO;
1111 		goto fail3;
1112 	}
1113 	efx->mem_bar = bar;
1114 	efx->membase = ioremap(efx->membase_phys, mem_map_size);
1115 	if (!efx->membase) {
1116 		pci_err(efx->pci_dev,
1117 			"could not map memory BAR[%d] at %llx+%x\n", bar,
1118 			(unsigned long long)efx->membase_phys, mem_map_size);
1119 		rc = -ENOMEM;
1120 		goto fail4;
1121 	}
1122 	pci_dbg(efx->pci_dev,
1123 		"memory BAR[%d] at %llx+%x (virtual %p)\n", bar,
1124 		(unsigned long long)efx->membase_phys, mem_map_size,
1125 		efx->membase);
1126 
1127 	return 0;
1128 
1129 fail4:
1130 	pci_release_region(efx->pci_dev, bar);
1131 fail3:
1132 	efx->membase_phys = 0;
1133 fail2:
1134 	pci_disable_device(efx->pci_dev);
1135 fail1:
1136 	return rc;
1137 }
1138 
1139 void efx_fini_io(struct efx_nic *efx)
1140 {
1141 	pci_dbg(efx->pci_dev, "shutting down I/O\n");
1142 
1143 	if (efx->membase) {
1144 		iounmap(efx->membase);
1145 		efx->membase = NULL;
1146 	}
1147 
1148 	if (efx->membase_phys) {
1149 		pci_release_region(efx->pci_dev, efx->mem_bar);
1150 		efx->membase_phys = 0;
1151 		efx->mem_bar = UINT_MAX;
1152 	}
1153 
1154 	/* Don't disable bus-mastering if VFs are assigned */
1155 	if (!pci_vfs_assigned(efx->pci_dev))
1156 		pci_disable_device(efx->pci_dev);
1157 }
1158 
1159 #ifdef CONFIG_SFC_MCDI_LOGGING
1160 static ssize_t mcdi_logging_show(struct device *dev,
1161 				 struct device_attribute *attr,
1162 				 char *buf)
1163 {
1164 	struct efx_nic *efx = dev_get_drvdata(dev);
1165 	struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
1166 
1167 	return scnprintf(buf, PAGE_SIZE, "%d\n", mcdi->logging_enabled);
1168 }
1169 
1170 static ssize_t mcdi_logging_store(struct device *dev,
1171 				  struct device_attribute *attr,
1172 				  const char *buf, size_t count)
1173 {
1174 	struct efx_nic *efx = dev_get_drvdata(dev);
1175 	struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
1176 	bool enable = count > 0 && *buf != '0';
1177 
1178 	mcdi->logging_enabled = enable;
1179 	return count;
1180 }
1181 
1182 static DEVICE_ATTR_RW(mcdi_logging);
1183 
1184 void efx_init_mcdi_logging(struct efx_nic *efx)
1185 {
1186 	int rc = device_create_file(&efx->pci_dev->dev, &dev_attr_mcdi_logging);
1187 
1188 	if (rc) {
1189 		netif_warn(efx, drv, efx->net_dev,
1190 			   "failed to init net dev attributes\n");
1191 	}
1192 }
1193 
1194 void efx_fini_mcdi_logging(struct efx_nic *efx)
1195 {
1196 	device_remove_file(&efx->pci_dev->dev, &dev_attr_mcdi_logging);
1197 }
1198 #endif
1199 
1200 /* A PCI error affecting this device was detected.
1201  * At this point MMIO and DMA may be disabled.
1202  * Stop the software path and request a slot reset.
1203  */
1204 static pci_ers_result_t efx_io_error_detected(struct pci_dev *pdev,
1205 					      pci_channel_state_t state)
1206 {
1207 	pci_ers_result_t status = PCI_ERS_RESULT_RECOVERED;
1208 	struct efx_nic *efx = pci_get_drvdata(pdev);
1209 
1210 	if (state == pci_channel_io_perm_failure)
1211 		return PCI_ERS_RESULT_DISCONNECT;
1212 
1213 	rtnl_lock();
1214 
1215 	if (efx->state != STATE_DISABLED) {
1216 		efx->state = efx_recover(efx->state);
1217 		efx->reset_pending = 0;
1218 
1219 		efx_device_detach_sync(efx);
1220 
1221 		if (efx_net_active(efx->state)) {
1222 			efx_stop_all(efx);
1223 			efx_disable_interrupts(efx);
1224 		}
1225 
1226 		status = PCI_ERS_RESULT_NEED_RESET;
1227 	} else {
1228 		/* If the interface is disabled we don't want to do anything
1229 		 * with it.
1230 		 */
1231 		status = PCI_ERS_RESULT_RECOVERED;
1232 	}
1233 
1234 	rtnl_unlock();
1235 
1236 	pci_disable_device(pdev);
1237 
1238 	return status;
1239 }
1240 
1241 /* Fake a successful reset, which will be performed later in efx_io_resume. */
1242 static pci_ers_result_t efx_io_slot_reset(struct pci_dev *pdev)
1243 {
1244 	struct efx_nic *efx = pci_get_drvdata(pdev);
1245 	pci_ers_result_t status = PCI_ERS_RESULT_RECOVERED;
1246 
1247 	if (pci_enable_device(pdev)) {
1248 		netif_err(efx, hw, efx->net_dev,
1249 			  "Cannot re-enable PCI device after reset.\n");
1250 		status =  PCI_ERS_RESULT_DISCONNECT;
1251 	}
1252 
1253 	return status;
1254 }
1255 
1256 /* Perform the actual reset and resume I/O operations. */
1257 static void efx_io_resume(struct pci_dev *pdev)
1258 {
1259 	struct efx_nic *efx = pci_get_drvdata(pdev);
1260 	int rc;
1261 
1262 	rtnl_lock();
1263 
1264 	if (efx->state == STATE_DISABLED)
1265 		goto out;
1266 
1267 	rc = efx_reset(efx, RESET_TYPE_ALL);
1268 	if (rc) {
1269 		netif_err(efx, hw, efx->net_dev,
1270 			  "efx_reset failed after PCI error (%d)\n", rc);
1271 	} else {
1272 		efx->state = efx_recovered(efx->state);
1273 		netif_dbg(efx, hw, efx->net_dev,
1274 			  "Done resetting and resuming IO after PCI error.\n");
1275 	}
1276 
1277 out:
1278 	rtnl_unlock();
1279 }
1280 
1281 /* For simplicity and reliability, we always require a slot reset and try to
1282  * reset the hardware when a pci error affecting the device is detected.
1283  * We leave both the link_reset and mmio_enabled callback unimplemented:
1284  * with our request for slot reset the mmio_enabled callback will never be
1285  * called, and the link_reset callback is not used by AER or EEH mechanisms.
1286  */
1287 const struct pci_error_handlers efx_err_handlers = {
1288 	.error_detected = efx_io_error_detected,
1289 	.slot_reset	= efx_io_slot_reset,
1290 	.resume		= efx_io_resume,
1291 };
1292 
1293 /* Determine whether the NIC will be able to handle TX offloads for a given
1294  * encapsulated packet.
1295  */
1296 static bool efx_can_encap_offloads(struct efx_nic *efx, struct sk_buff *skb)
1297 {
1298 	struct gre_base_hdr *greh;
1299 	__be16 dst_port;
1300 	u8 ipproto;
1301 
1302 	/* Does the NIC support encap offloads?
1303 	 * If not, we should never get here, because we shouldn't have
1304 	 * advertised encap offload feature flags in the first place.
1305 	 */
1306 	if (WARN_ON_ONCE(!efx->type->udp_tnl_has_port))
1307 		return false;
1308 
1309 	/* Determine encapsulation protocol in use */
1310 	switch (skb->protocol) {
1311 	case htons(ETH_P_IP):
1312 		ipproto = ip_hdr(skb)->protocol;
1313 		break;
1314 	case htons(ETH_P_IPV6):
1315 		/* If there are extension headers, this will cause us to
1316 		 * think we can't offload something that we maybe could have.
1317 		 */
1318 		ipproto = ipv6_hdr(skb)->nexthdr;
1319 		break;
1320 	default:
1321 		/* Not IP, so can't offload it */
1322 		return false;
1323 	}
1324 	switch (ipproto) {
1325 	case IPPROTO_GRE:
1326 		/* We support NVGRE but not IP over GRE or random gretaps.
1327 		 * Specifically, the NIC will accept GRE as encapsulated if
1328 		 * the inner protocol is Ethernet, but only handle it
1329 		 * correctly if the GRE header is 8 bytes long.  Moreover,
1330 		 * it will not update the Checksum or Sequence Number fields
1331 		 * if they are present.  (The Routing Present flag,
1332 		 * GRE_ROUTING, cannot be set else the header would be more
1333 		 * than 8 bytes long; so we don't have to worry about it.)
1334 		 */
1335 		if (skb->inner_protocol_type != ENCAP_TYPE_ETHER)
1336 			return false;
1337 		if (ntohs(skb->inner_protocol) != ETH_P_TEB)
1338 			return false;
1339 		if (skb_inner_mac_header(skb) - skb_transport_header(skb) != 8)
1340 			return false;
1341 		greh = (struct gre_base_hdr *)skb_transport_header(skb);
1342 		return !(greh->flags & (GRE_CSUM | GRE_SEQ));
1343 	case IPPROTO_UDP:
1344 		/* If the port is registered for a UDP tunnel, we assume the
1345 		 * packet is for that tunnel, and the NIC will handle it as
1346 		 * such.  If not, the NIC won't know what to do with it.
1347 		 */
1348 		dst_port = udp_hdr(skb)->dest;
1349 		return efx->type->udp_tnl_has_port(efx, dst_port);
1350 	default:
1351 		return false;
1352 	}
1353 }
1354 
1355 netdev_features_t efx_features_check(struct sk_buff *skb, struct net_device *dev,
1356 				     netdev_features_t features)
1357 {
1358 	struct efx_nic *efx = efx_netdev_priv(dev);
1359 
1360 	if (skb->encapsulation) {
1361 		if (features & NETIF_F_GSO_MASK)
1362 			/* Hardware can only do TSO with at most 208 bytes
1363 			 * of headers.
1364 			 */
1365 			if (skb_inner_transport_offset(skb) >
1366 			    EFX_TSO2_MAX_HDRLEN)
1367 				features &= ~(NETIF_F_GSO_MASK);
1368 		if (features & (NETIF_F_GSO_MASK | NETIF_F_CSUM_MASK))
1369 			if (!efx_can_encap_offloads(efx, skb))
1370 				features &= ~(NETIF_F_GSO_MASK |
1371 					      NETIF_F_CSUM_MASK);
1372 	}
1373 	return features;
1374 }
1375 
1376 int efx_get_phys_port_id(struct net_device *net_dev,
1377 			 struct netdev_phys_item_id *ppid)
1378 {
1379 	struct efx_nic *efx = efx_netdev_priv(net_dev);
1380 
1381 	if (efx->type->get_phys_port_id)
1382 		return efx->type->get_phys_port_id(efx, ppid);
1383 	else
1384 		return -EOPNOTSUPP;
1385 }
1386 
1387 int efx_get_phys_port_name(struct net_device *net_dev, char *name, size_t len)
1388 {
1389 	struct efx_nic *efx = efx_netdev_priv(net_dev);
1390 
1391 	if (snprintf(name, len, "p%u", efx->port_num) >= len)
1392 		return -EINVAL;
1393 	return 0;
1394 }
1395 
1396 void efx_detach_reps(struct efx_nic *efx)
1397 {
1398 	struct net_device *rep_dev;
1399 	struct efx_rep *efv;
1400 
1401 	ASSERT_RTNL();
1402 	netif_dbg(efx, drv, efx->net_dev, "Detaching VF representors\n");
1403 	list_for_each_entry(efv, &efx->vf_reps, list) {
1404 		rep_dev = efv->net_dev;
1405 		if (!rep_dev)
1406 			continue;
1407 		netif_carrier_off(rep_dev);
1408 		/* See efx_device_detach_sync() */
1409 		netif_tx_lock_bh(rep_dev);
1410 		netif_tx_stop_all_queues(rep_dev);
1411 		netif_tx_unlock_bh(rep_dev);
1412 	}
1413 }
1414 
1415 void efx_attach_reps(struct efx_nic *efx)
1416 {
1417 	struct net_device *rep_dev;
1418 	struct efx_rep *efv;
1419 
1420 	ASSERT_RTNL();
1421 	netif_dbg(efx, drv, efx->net_dev, "Attaching VF representors\n");
1422 	list_for_each_entry(efv, &efx->vf_reps, list) {
1423 		rep_dev = efv->net_dev;
1424 		if (!rep_dev)
1425 			continue;
1426 		netif_tx_wake_all_queues(rep_dev);
1427 		netif_carrier_on(rep_dev);
1428 	}
1429 }
1430