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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2004-2013 Synopsys, Inc. (www.synopsys.com)
4 *
5 * Driver for the ARC EMAC 10100 (hardware revision 5)
6 *
7 * Contributors:
8 * Amit Bhor
9 * Sameer Dhavale
10 * Vineet Gupta
11 */
12
13#include <linux/crc32.h>
14#include <linux/etherdevice.h>
15#include <linux/interrupt.h>
16#include <linux/io.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/of_address.h>
20#include <linux/of_irq.h>
21#include <linux/of_mdio.h>
22#include <linux/of_net.h>
23
24#include "emac.h"
25
26static void arc_emac_restart(struct net_device *ndev);
27
28/**
29 * arc_emac_tx_avail - Return the number of available slots in the tx ring.
30 * @priv: Pointer to ARC EMAC private data structure.
31 *
32 * returns: the number of slots available for transmission in tx the ring.
33 */
34static inline int arc_emac_tx_avail(struct arc_emac_priv *priv)
35{
36 return (priv->txbd_dirty + TX_BD_NUM - priv->txbd_curr - 1) % TX_BD_NUM;
37}
38
39/**
40 * arc_emac_adjust_link - Adjust the PHY link duplex.
41 * @ndev: Pointer to the net_device structure.
42 *
43 * This function is called to change the duplex setting after auto negotiation
44 * is done by the PHY.
45 */
46static void arc_emac_adjust_link(struct net_device *ndev)
47{
48 struct arc_emac_priv *priv = netdev_priv(ndev);
49 struct phy_device *phy_dev = ndev->phydev;
50 unsigned int reg, state_changed = 0;
51
52 if (priv->link != phy_dev->link) {
53 priv->link = phy_dev->link;
54 state_changed = 1;
55 }
56
57 if (priv->speed != phy_dev->speed) {
58 priv->speed = phy_dev->speed;
59 state_changed = 1;
60 if (priv->set_mac_speed)
61 priv->set_mac_speed(priv, priv->speed);
62 }
63
64 if (priv->duplex != phy_dev->duplex) {
65 reg = arc_reg_get(priv, R_CTRL);
66
67 if (phy_dev->duplex == DUPLEX_FULL)
68 reg |= ENFL_MASK;
69 else
70 reg &= ~ENFL_MASK;
71
72 arc_reg_set(priv, R_CTRL, reg);
73 priv->duplex = phy_dev->duplex;
74 state_changed = 1;
75 }
76
77 if (state_changed)
78 phy_print_status(phy_dev);
79}
80
81/**
82 * arc_emac_get_drvinfo - Get EMAC driver information.
83 * @ndev: Pointer to net_device structure.
84 * @info: Pointer to ethtool_drvinfo structure.
85 *
86 * This implements ethtool command for getting the driver information.
87 * Issue "ethtool -i ethX" under linux prompt to execute this function.
88 */
89static void arc_emac_get_drvinfo(struct net_device *ndev,
90 struct ethtool_drvinfo *info)
91{
92 struct arc_emac_priv *priv = netdev_priv(ndev);
93
94 strscpy(info->driver, priv->drv_name, sizeof(info->driver));
95}
96
97static const struct ethtool_ops arc_emac_ethtool_ops = {
98 .get_drvinfo = arc_emac_get_drvinfo,
99 .get_link = ethtool_op_get_link,
100 .get_link_ksettings = phy_ethtool_get_link_ksettings,
101 .set_link_ksettings = phy_ethtool_set_link_ksettings,
102};
103
104#define FIRST_OR_LAST_MASK (FIRST_MASK | LAST_MASK)
105
106/**
107 * arc_emac_tx_clean - clears processed by EMAC Tx BDs.
108 * @ndev: Pointer to the network device.
109 */
110static void arc_emac_tx_clean(struct net_device *ndev)
111{
112 struct arc_emac_priv *priv = netdev_priv(ndev);
113 struct net_device_stats *stats = &ndev->stats;
114 struct device *dev = ndev->dev.parent;
115 unsigned int i;
116
117 for (i = 0; i < TX_BD_NUM; i++) {
118 unsigned int *txbd_dirty = &priv->txbd_dirty;
119 struct arc_emac_bd *txbd = &priv->txbd[*txbd_dirty];
120 struct buffer_state *tx_buff = &priv->tx_buff[*txbd_dirty];
121 struct sk_buff *skb = tx_buff->skb;
122 unsigned int info = le32_to_cpu(txbd->info);
123
124 if ((info & FOR_EMAC) || !txbd->data || !skb)
125 break;
126
127 if (unlikely(info & (DROP | DEFR | LTCL | UFLO))) {
128 stats->tx_errors++;
129 stats->tx_dropped++;
130
131 if (info & DEFR)
132 stats->tx_carrier_errors++;
133
134 if (info & LTCL)
135 stats->collisions++;
136
137 if (info & UFLO)
138 stats->tx_fifo_errors++;
139 } else if (likely(info & FIRST_OR_LAST_MASK)) {
140 stats->tx_packets++;
141 stats->tx_bytes += skb->len;
142 }
143
144 dma_unmap_single(dev, dma_unmap_addr(tx_buff, addr),
145 dma_unmap_len(tx_buff, len), DMA_TO_DEVICE);
146
147 /* return the sk_buff to system */
148 dev_consume_skb_irq(skb);
149
150 txbd->data = 0;
151 txbd->info = 0;
152 tx_buff->skb = NULL;
153
154 *txbd_dirty = (*txbd_dirty + 1) % TX_BD_NUM;
155 }
156
157 /* Ensure that txbd_dirty is visible to tx() before checking
158 * for queue stopped.
159 */
160 smp_mb();
161
162 if (netif_queue_stopped(ndev) && arc_emac_tx_avail(priv))
163 netif_wake_queue(ndev);
164}
165
166/**
167 * arc_emac_rx - processing of Rx packets.
168 * @ndev: Pointer to the network device.
169 * @budget: How many BDs to process on 1 call.
170 *
171 * returns: Number of processed BDs
172 *
173 * Iterate through Rx BDs and deliver received packages to upper layer.
174 */
175static int arc_emac_rx(struct net_device *ndev, int budget)
176{
177 struct arc_emac_priv *priv = netdev_priv(ndev);
178 struct device *dev = ndev->dev.parent;
179 unsigned int work_done;
180
181 for (work_done = 0; work_done < budget; work_done++) {
182 unsigned int *last_rx_bd = &priv->last_rx_bd;
183 struct net_device_stats *stats = &ndev->stats;
184 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd];
185 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd];
186 unsigned int pktlen, info = le32_to_cpu(rxbd->info);
187 struct sk_buff *skb;
188 dma_addr_t addr;
189
190 if (unlikely((info & OWN_MASK) == FOR_EMAC))
191 break;
192
193 /* Make a note that we saw a packet at this BD.
194 * So next time, driver starts from this + 1
195 */
196 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM;
197
198 if (unlikely((info & FIRST_OR_LAST_MASK) !=
199 FIRST_OR_LAST_MASK)) {
200 /* We pre-allocate buffers of MTU size so incoming
201 * packets won't be split/chained.
202 */
203 if (net_ratelimit())
204 netdev_err(ndev, "incomplete packet received\n");
205
206 /* Return ownership to EMAC */
207 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
208 stats->rx_errors++;
209 stats->rx_length_errors++;
210 continue;
211 }
212
213 /* Prepare the BD for next cycle. netif_receive_skb()
214 * only if new skb was allocated and mapped to avoid holes
215 * in the RX fifo.
216 */
217 skb = netdev_alloc_skb_ip_align(ndev, EMAC_BUFFER_SIZE);
218 if (unlikely(!skb)) {
219 if (net_ratelimit())
220 netdev_err(ndev, "cannot allocate skb\n");
221 /* Return ownership to EMAC */
222 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
223 stats->rx_errors++;
224 stats->rx_dropped++;
225 continue;
226 }
227
228 addr = dma_map_single(dev, (void *)skb->data,
229 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE);
230 if (dma_mapping_error(dev, addr)) {
231 if (net_ratelimit())
232 netdev_err(ndev, "cannot map dma buffer\n");
233 dev_kfree_skb(skb);
234 /* Return ownership to EMAC */
235 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
236 stats->rx_errors++;
237 stats->rx_dropped++;
238 continue;
239 }
240
241 /* unmap previosly mapped skb */
242 dma_unmap_single(dev, dma_unmap_addr(rx_buff, addr),
243 dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE);
244
245 pktlen = info & LEN_MASK;
246 stats->rx_packets++;
247 stats->rx_bytes += pktlen;
248 skb_put(rx_buff->skb, pktlen);
249 rx_buff->skb->dev = ndev;
250 rx_buff->skb->protocol = eth_type_trans(rx_buff->skb, ndev);
251
252 netif_receive_skb(rx_buff->skb);
253
254 rx_buff->skb = skb;
255 dma_unmap_addr_set(rx_buff, addr, addr);
256 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE);
257
258 rxbd->data = cpu_to_le32(addr);
259
260 /* Make sure pointer to data buffer is set */
261 wmb();
262
263 /* Return ownership to EMAC */
264 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
265 }
266
267 return work_done;
268}
269
270/**
271 * arc_emac_rx_miss_handle - handle R_MISS register
272 * @ndev: Pointer to the net_device structure.
273 */
274static void arc_emac_rx_miss_handle(struct net_device *ndev)
275{
276 struct arc_emac_priv *priv = netdev_priv(ndev);
277 struct net_device_stats *stats = &ndev->stats;
278 unsigned int miss;
279
280 miss = arc_reg_get(priv, R_MISS);
281 if (miss) {
282 stats->rx_errors += miss;
283 stats->rx_missed_errors += miss;
284 priv->rx_missed_errors += miss;
285 }
286}
287
288/**
289 * arc_emac_rx_stall_check - check RX stall
290 * @ndev: Pointer to the net_device structure.
291 * @budget: How many BDs requested to process on 1 call.
292 * @work_done: How many BDs processed
293 *
294 * Under certain conditions EMAC stop reception of incoming packets and
295 * continuously increment R_MISS register instead of saving data into
296 * provided buffer. This function detect that condition and restart
297 * EMAC.
298 */
299static void arc_emac_rx_stall_check(struct net_device *ndev,
300 int budget, unsigned int work_done)
301{
302 struct arc_emac_priv *priv = netdev_priv(ndev);
303 struct arc_emac_bd *rxbd;
304
305 if (work_done)
306 priv->rx_missed_errors = 0;
307
308 if (priv->rx_missed_errors && budget) {
309 rxbd = &priv->rxbd[priv->last_rx_bd];
310 if (le32_to_cpu(rxbd->info) & FOR_EMAC) {
311 arc_emac_restart(ndev);
312 priv->rx_missed_errors = 0;
313 }
314 }
315}
316
317/**
318 * arc_emac_poll - NAPI poll handler.
319 * @napi: Pointer to napi_struct structure.
320 * @budget: How many BDs to process on 1 call.
321 *
322 * returns: Number of processed BDs
323 */
324static int arc_emac_poll(struct napi_struct *napi, int budget)
325{
326 struct net_device *ndev = napi->dev;
327 struct arc_emac_priv *priv = netdev_priv(ndev);
328 unsigned int work_done;
329
330 arc_emac_tx_clean(ndev);
331 arc_emac_rx_miss_handle(ndev);
332
333 work_done = arc_emac_rx(ndev, budget);
334 if (work_done < budget) {
335 napi_complete_done(napi, work_done);
336 arc_reg_or(priv, R_ENABLE, RXINT_MASK | TXINT_MASK);
337 }
338
339 arc_emac_rx_stall_check(ndev, budget, work_done);
340
341 return work_done;
342}
343
344/**
345 * arc_emac_intr - Global interrupt handler for EMAC.
346 * @irq: irq number.
347 * @dev_instance: device instance.
348 *
349 * returns: IRQ_HANDLED for all cases.
350 *
351 * ARC EMAC has only 1 interrupt line, and depending on bits raised in
352 * STATUS register we may tell what is a reason for interrupt to fire.
353 */
354static irqreturn_t arc_emac_intr(int irq, void *dev_instance)
355{
356 struct net_device *ndev = dev_instance;
357 struct arc_emac_priv *priv = netdev_priv(ndev);
358 struct net_device_stats *stats = &ndev->stats;
359 unsigned int status;
360
361 status = arc_reg_get(priv, R_STATUS);
362 status &= ~MDIO_MASK;
363
364 /* Reset all flags except "MDIO complete" */
365 arc_reg_set(priv, R_STATUS, status);
366
367 if (status & (RXINT_MASK | TXINT_MASK)) {
368 if (likely(napi_schedule_prep(&priv->napi))) {
369 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK);
370 __napi_schedule(&priv->napi);
371 }
372 }
373
374 if (status & ERR_MASK) {
375 /* MSER/RXCR/RXFR/RXFL interrupt fires on corresponding
376 * 8-bit error counter overrun.
377 */
378
379 if (status & MSER_MASK) {
380 stats->rx_missed_errors += 0x100;
381 stats->rx_errors += 0x100;
382 priv->rx_missed_errors += 0x100;
383 napi_schedule(&priv->napi);
384 }
385
386 if (status & RXCR_MASK) {
387 stats->rx_crc_errors += 0x100;
388 stats->rx_errors += 0x100;
389 }
390
391 if (status & RXFR_MASK) {
392 stats->rx_frame_errors += 0x100;
393 stats->rx_errors += 0x100;
394 }
395
396 if (status & RXFL_MASK) {
397 stats->rx_over_errors += 0x100;
398 stats->rx_errors += 0x100;
399 }
400 }
401
402 return IRQ_HANDLED;
403}
404
405#ifdef CONFIG_NET_POLL_CONTROLLER
406static void arc_emac_poll_controller(struct net_device *dev)
407{
408 disable_irq(dev->irq);
409 arc_emac_intr(dev->irq, dev);
410 enable_irq(dev->irq);
411}
412#endif
413
414/**
415 * arc_emac_open - Open the network device.
416 * @ndev: Pointer to the network device.
417 *
418 * returns: 0, on success or non-zero error value on failure.
419 *
420 * This function sets the MAC address, requests and enables an IRQ
421 * for the EMAC device and starts the Tx queue.
422 * It also connects to the phy device.
423 */
424static int arc_emac_open(struct net_device *ndev)
425{
426 struct arc_emac_priv *priv = netdev_priv(ndev);
427 struct phy_device *phy_dev = ndev->phydev;
428 struct device *dev = ndev->dev.parent;
429 int i;
430
431 phy_dev->autoneg = AUTONEG_ENABLE;
432 phy_dev->speed = 0;
433 phy_dev->duplex = 0;
434 linkmode_and(phy_dev->advertising, phy_dev->advertising,
435 phy_dev->supported);
436
437 priv->last_rx_bd = 0;
438
439 /* Allocate and set buffers for Rx BD's */
440 for (i = 0; i < RX_BD_NUM; i++) {
441 dma_addr_t addr;
442 unsigned int *last_rx_bd = &priv->last_rx_bd;
443 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd];
444 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd];
445
446 rx_buff->skb = netdev_alloc_skb_ip_align(ndev,
447 EMAC_BUFFER_SIZE);
448 if (unlikely(!rx_buff->skb))
449 return -ENOMEM;
450
451 addr = dma_map_single(dev, (void *)rx_buff->skb->data,
452 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE);
453 if (dma_mapping_error(dev, addr)) {
454 netdev_err(ndev, "cannot dma map\n");
455 dev_kfree_skb(rx_buff->skb);
456 return -ENOMEM;
457 }
458 dma_unmap_addr_set(rx_buff, addr, addr);
459 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE);
460
461 rxbd->data = cpu_to_le32(addr);
462
463 /* Make sure pointer to data buffer is set */
464 wmb();
465
466 /* Return ownership to EMAC */
467 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
468
469 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM;
470 }
471
472 priv->txbd_curr = 0;
473 priv->txbd_dirty = 0;
474
475 /* Clean Tx BD's */
476 memset(priv->txbd, 0, TX_RING_SZ);
477
478 /* Initialize logical address filter */
479 arc_reg_set(priv, R_LAFL, 0);
480 arc_reg_set(priv, R_LAFH, 0);
481
482 /* Set BD ring pointers for device side */
483 arc_reg_set(priv, R_RX_RING, (unsigned int)priv->rxbd_dma);
484 arc_reg_set(priv, R_TX_RING, (unsigned int)priv->txbd_dma);
485
486 /* Enable interrupts */
487 arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK);
488
489 /* Set CONTROL */
490 arc_reg_set(priv, R_CTRL,
491 (RX_BD_NUM << 24) | /* RX BD table length */
492 (TX_BD_NUM << 16) | /* TX BD table length */
493 TXRN_MASK | RXRN_MASK);
494
495 napi_enable(&priv->napi);
496
497 /* Enable EMAC */
498 arc_reg_or(priv, R_CTRL, EN_MASK);
499
500 phy_start(ndev->phydev);
501
502 netif_start_queue(ndev);
503
504 return 0;
505}
506
507/**
508 * arc_emac_set_rx_mode - Change the receive filtering mode.
509 * @ndev: Pointer to the network device.
510 *
511 * This function enables/disables promiscuous or all-multicast mode
512 * and updates the multicast filtering list of the network device.
513 */
514static void arc_emac_set_rx_mode(struct net_device *ndev)
515{
516 struct arc_emac_priv *priv = netdev_priv(ndev);
517
518 if (ndev->flags & IFF_PROMISC) {
519 arc_reg_or(priv, R_CTRL, PROM_MASK);
520 } else {
521 arc_reg_clr(priv, R_CTRL, PROM_MASK);
522
523 if (ndev->flags & IFF_ALLMULTI) {
524 arc_reg_set(priv, R_LAFL, ~0);
525 arc_reg_set(priv, R_LAFH, ~0);
526 } else if (ndev->flags & IFF_MULTICAST) {
527 struct netdev_hw_addr *ha;
528 unsigned int filter[2] = { 0, 0 };
529 int bit;
530
531 netdev_for_each_mc_addr(ha, ndev) {
532 bit = ether_crc_le(ETH_ALEN, ha->addr) >> 26;
533 filter[bit >> 5] |= 1 << (bit & 31);
534 }
535
536 arc_reg_set(priv, R_LAFL, filter[0]);
537 arc_reg_set(priv, R_LAFH, filter[1]);
538 } else {
539 arc_reg_set(priv, R_LAFL, 0);
540 arc_reg_set(priv, R_LAFH, 0);
541 }
542 }
543}
544
545/**
546 * arc_free_tx_queue - free skb from tx queue
547 * @ndev: Pointer to the network device.
548 *
549 * This function must be called while EMAC disable
550 */
551static void arc_free_tx_queue(struct net_device *ndev)
552{
553 struct arc_emac_priv *priv = netdev_priv(ndev);
554 struct device *dev = ndev->dev.parent;
555 unsigned int i;
556
557 for (i = 0; i < TX_BD_NUM; i++) {
558 struct arc_emac_bd *txbd = &priv->txbd[i];
559 struct buffer_state *tx_buff = &priv->tx_buff[i];
560
561 if (tx_buff->skb) {
562 dma_unmap_single(dev,
563 dma_unmap_addr(tx_buff, addr),
564 dma_unmap_len(tx_buff, len),
565 DMA_TO_DEVICE);
566
567 /* return the sk_buff to system */
568 dev_kfree_skb_irq(tx_buff->skb);
569 }
570
571 txbd->info = 0;
572 txbd->data = 0;
573 tx_buff->skb = NULL;
574 }
575}
576
577/**
578 * arc_free_rx_queue - free skb from rx queue
579 * @ndev: Pointer to the network device.
580 *
581 * This function must be called while EMAC disable
582 */
583static void arc_free_rx_queue(struct net_device *ndev)
584{
585 struct arc_emac_priv *priv = netdev_priv(ndev);
586 struct device *dev = ndev->dev.parent;
587 unsigned int i;
588
589 for (i = 0; i < RX_BD_NUM; i++) {
590 struct arc_emac_bd *rxbd = &priv->rxbd[i];
591 struct buffer_state *rx_buff = &priv->rx_buff[i];
592
593 if (rx_buff->skb) {
594 dma_unmap_single(dev,
595 dma_unmap_addr(rx_buff, addr),
596 dma_unmap_len(rx_buff, len),
597 DMA_FROM_DEVICE);
598
599 /* return the sk_buff to system */
600 dev_kfree_skb_irq(rx_buff->skb);
601 }
602
603 rxbd->info = 0;
604 rxbd->data = 0;
605 rx_buff->skb = NULL;
606 }
607}
608
609/**
610 * arc_emac_stop - Close the network device.
611 * @ndev: Pointer to the network device.
612 *
613 * This function stops the Tx queue, disables interrupts and frees the IRQ for
614 * the EMAC device.
615 * It also disconnects the PHY device associated with the EMAC device.
616 */
617static int arc_emac_stop(struct net_device *ndev)
618{
619 struct arc_emac_priv *priv = netdev_priv(ndev);
620
621 napi_disable(&priv->napi);
622 netif_stop_queue(ndev);
623
624 phy_stop(ndev->phydev);
625
626 /* Disable interrupts */
627 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK);
628
629 /* Disable EMAC */
630 arc_reg_clr(priv, R_CTRL, EN_MASK);
631
632 /* Return the sk_buff to system */
633 arc_free_tx_queue(ndev);
634 arc_free_rx_queue(ndev);
635
636 return 0;
637}
638
639/**
640 * arc_emac_stats - Get system network statistics.
641 * @ndev: Pointer to net_device structure.
642 *
643 * Returns the address of the device statistics structure.
644 * Statistics are updated in interrupt handler.
645 */
646static struct net_device_stats *arc_emac_stats(struct net_device *ndev)
647{
648 struct arc_emac_priv *priv = netdev_priv(ndev);
649 struct net_device_stats *stats = &ndev->stats;
650 unsigned long miss, rxerr;
651 u8 rxcrc, rxfram, rxoflow;
652
653 rxerr = arc_reg_get(priv, R_RXERR);
654 miss = arc_reg_get(priv, R_MISS);
655
656 rxcrc = rxerr;
657 rxfram = rxerr >> 8;
658 rxoflow = rxerr >> 16;
659
660 stats->rx_errors += miss;
661 stats->rx_errors += rxcrc + rxfram + rxoflow;
662
663 stats->rx_over_errors += rxoflow;
664 stats->rx_frame_errors += rxfram;
665 stats->rx_crc_errors += rxcrc;
666 stats->rx_missed_errors += miss;
667
668 return stats;
669}
670
671/**
672 * arc_emac_tx - Starts the data transmission.
673 * @skb: sk_buff pointer that contains data to be Transmitted.
674 * @ndev: Pointer to net_device structure.
675 *
676 * returns: NETDEV_TX_OK, on success
677 * NETDEV_TX_BUSY, if any of the descriptors are not free.
678 *
679 * This function is invoked from upper layers to initiate transmission.
680 */
681static netdev_tx_t arc_emac_tx(struct sk_buff *skb, struct net_device *ndev)
682{
683 struct arc_emac_priv *priv = netdev_priv(ndev);
684 unsigned int len, *txbd_curr = &priv->txbd_curr;
685 struct net_device_stats *stats = &ndev->stats;
686 __le32 *info = &priv->txbd[*txbd_curr].info;
687 struct device *dev = ndev->dev.parent;
688 dma_addr_t addr;
689
690 if (skb_padto(skb, ETH_ZLEN))
691 return NETDEV_TX_OK;
692
693 len = max_t(unsigned int, ETH_ZLEN, skb->len);
694
695 if (unlikely(!arc_emac_tx_avail(priv))) {
696 netif_stop_queue(ndev);
697 netdev_err(ndev, "BUG! Tx Ring full when queue awake!\n");
698 return NETDEV_TX_BUSY;
699 }
700
701 addr = dma_map_single(dev, (void *)skb->data, len, DMA_TO_DEVICE);
702
703 if (unlikely(dma_mapping_error(dev, addr))) {
704 stats->tx_dropped++;
705 stats->tx_errors++;
706 dev_kfree_skb_any(skb);
707 return NETDEV_TX_OK;
708 }
709 dma_unmap_addr_set(&priv->tx_buff[*txbd_curr], addr, addr);
710 dma_unmap_len_set(&priv->tx_buff[*txbd_curr], len, len);
711
712 priv->txbd[*txbd_curr].data = cpu_to_le32(addr);
713
714 /* Make sure pointer to data buffer is set */
715 wmb();
716
717 skb_tx_timestamp(skb);
718
719 *info = cpu_to_le32(FOR_EMAC | FIRST_OR_LAST_MASK | len);
720
721 /* Make sure info word is set */
722 wmb();
723
724 priv->tx_buff[*txbd_curr].skb = skb;
725
726 /* Increment index to point to the next BD */
727 *txbd_curr = (*txbd_curr + 1) % TX_BD_NUM;
728
729 /* Ensure that tx_clean() sees the new txbd_curr before
730 * checking the queue status. This prevents an unneeded wake
731 * of the queue in tx_clean().
732 */
733 smp_mb();
734
735 if (!arc_emac_tx_avail(priv)) {
736 netif_stop_queue(ndev);
737 /* Refresh tx_dirty */
738 smp_mb();
739 if (arc_emac_tx_avail(priv))
740 netif_start_queue(ndev);
741 }
742
743 arc_reg_set(priv, R_STATUS, TXPL_MASK);
744
745 return NETDEV_TX_OK;
746}
747
748static void arc_emac_set_address_internal(struct net_device *ndev)
749{
750 struct arc_emac_priv *priv = netdev_priv(ndev);
751 unsigned int addr_low, addr_hi;
752
753 addr_low = le32_to_cpu(*(__le32 *)&ndev->dev_addr[0]);
754 addr_hi = le16_to_cpu(*(__le16 *)&ndev->dev_addr[4]);
755
756 arc_reg_set(priv, R_ADDRL, addr_low);
757 arc_reg_set(priv, R_ADDRH, addr_hi);
758}
759
760/**
761 * arc_emac_set_address - Set the MAC address for this device.
762 * @ndev: Pointer to net_device structure.
763 * @p: 6 byte Address to be written as MAC address.
764 *
765 * This function copies the HW address from the sockaddr structure to the
766 * net_device structure and updates the address in HW.
767 *
768 * returns: -EBUSY if the net device is busy or 0 if the address is set
769 * successfully.
770 */
771static int arc_emac_set_address(struct net_device *ndev, void *p)
772{
773 struct sockaddr *addr = p;
774
775 if (netif_running(ndev))
776 return -EBUSY;
777
778 if (!is_valid_ether_addr(addr->sa_data))
779 return -EADDRNOTAVAIL;
780
781 eth_hw_addr_set(ndev, addr->sa_data);
782
783 arc_emac_set_address_internal(ndev);
784
785 return 0;
786}
787
788/**
789 * arc_emac_restart - Restart EMAC
790 * @ndev: Pointer to net_device structure.
791 *
792 * This function do hardware reset of EMAC in order to restore
793 * network packets reception.
794 */
795static void arc_emac_restart(struct net_device *ndev)
796{
797 struct arc_emac_priv *priv = netdev_priv(ndev);
798 struct net_device_stats *stats = &ndev->stats;
799 int i;
800
801 if (net_ratelimit())
802 netdev_warn(ndev, "restarting stalled EMAC\n");
803
804 netif_stop_queue(ndev);
805
806 /* Disable interrupts */
807 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK);
808
809 /* Disable EMAC */
810 arc_reg_clr(priv, R_CTRL, EN_MASK);
811
812 /* Return the sk_buff to system */
813 arc_free_tx_queue(ndev);
814
815 /* Clean Tx BD's */
816 priv->txbd_curr = 0;
817 priv->txbd_dirty = 0;
818 memset(priv->txbd, 0, TX_RING_SZ);
819
820 for (i = 0; i < RX_BD_NUM; i++) {
821 struct arc_emac_bd *rxbd = &priv->rxbd[i];
822 unsigned int info = le32_to_cpu(rxbd->info);
823
824 if (!(info & FOR_EMAC)) {
825 stats->rx_errors++;
826 stats->rx_dropped++;
827 }
828 /* Return ownership to EMAC */
829 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
830 }
831 priv->last_rx_bd = 0;
832
833 /* Make sure info is visible to EMAC before enable */
834 wmb();
835
836 /* Enable interrupts */
837 arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK);
838
839 /* Enable EMAC */
840 arc_reg_or(priv, R_CTRL, EN_MASK);
841
842 netif_start_queue(ndev);
843}
844
845static const struct net_device_ops arc_emac_netdev_ops = {
846 .ndo_open = arc_emac_open,
847 .ndo_stop = arc_emac_stop,
848 .ndo_start_xmit = arc_emac_tx,
849 .ndo_set_mac_address = arc_emac_set_address,
850 .ndo_get_stats = arc_emac_stats,
851 .ndo_set_rx_mode = arc_emac_set_rx_mode,
852 .ndo_eth_ioctl = phy_do_ioctl_running,
853#ifdef CONFIG_NET_POLL_CONTROLLER
854 .ndo_poll_controller = arc_emac_poll_controller,
855#endif
856};
857
858int arc_emac_probe(struct net_device *ndev, int interface)
859{
860 struct device *dev = ndev->dev.parent;
861 struct resource res_regs;
862 struct device_node *phy_node;
863 struct phy_device *phydev = NULL;
864 struct arc_emac_priv *priv;
865 unsigned int id, clock_frequency, irq;
866 int err;
867
868 /* Get PHY from device tree */
869 phy_node = of_parse_phandle(dev->of_node, "phy", 0);
870 if (!phy_node) {
871 dev_err(dev, "failed to retrieve phy description from device tree\n");
872 return -ENODEV;
873 }
874
875 /* Get EMAC registers base address from device tree */
876 err = of_address_to_resource(dev->of_node, 0, &res_regs);
877 if (err) {
878 dev_err(dev, "failed to retrieve registers base from device tree\n");
879 err = -ENODEV;
880 goto out_put_node;
881 }
882
883 /* Get IRQ from device tree */
884 irq = irq_of_parse_and_map(dev->of_node, 0);
885 if (!irq) {
886 dev_err(dev, "failed to retrieve <irq> value from device tree\n");
887 err = -ENODEV;
888 goto out_put_node;
889 }
890
891 ndev->netdev_ops = &arc_emac_netdev_ops;
892 ndev->ethtool_ops = &arc_emac_ethtool_ops;
893 ndev->watchdog_timeo = TX_TIMEOUT;
894
895 priv = netdev_priv(ndev);
896 priv->dev = dev;
897
898 priv->regs = devm_ioremap_resource(dev, &res_regs);
899 if (IS_ERR(priv->regs)) {
900 err = PTR_ERR(priv->regs);
901 goto out_put_node;
902 }
903
904 dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs);
905
906 if (priv->clk) {
907 err = clk_prepare_enable(priv->clk);
908 if (err) {
909 dev_err(dev, "failed to enable clock\n");
910 goto out_put_node;
911 }
912
913 clock_frequency = clk_get_rate(priv->clk);
914 } else {
915 /* Get CPU clock frequency from device tree */
916 if (of_property_read_u32(dev->of_node, "clock-frequency",
917 &clock_frequency)) {
918 dev_err(dev, "failed to retrieve <clock-frequency> from device tree\n");
919 err = -EINVAL;
920 goto out_put_node;
921 }
922 }
923
924 id = arc_reg_get(priv, R_ID);
925
926 /* Check for EMAC revision 5 or 7, magic number */
927 if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
928 dev_err(dev, "ARC EMAC not detected, id=0x%x\n", id);
929 err = -ENODEV;
930 goto out_clken;
931 }
932 dev_info(dev, "ARC EMAC detected with id: 0x%x\n", id);
933
934 /* Set poll rate so that it polls every 1 ms */
935 arc_reg_set(priv, R_POLLRATE, clock_frequency / 1000000);
936
937 ndev->irq = irq;
938 dev_info(dev, "IRQ is %d\n", ndev->irq);
939
940 /* Register interrupt handler for device */
941 err = devm_request_irq(dev, ndev->irq, arc_emac_intr, 0,
942 ndev->name, ndev);
943 if (err) {
944 dev_err(dev, "could not allocate IRQ\n");
945 goto out_clken;
946 }
947
948 /* Get MAC address from device tree */
949 err = of_get_ethdev_address(dev->of_node, ndev);
950 if (err)
951 eth_hw_addr_random(ndev);
952
953 arc_emac_set_address_internal(ndev);
954 dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
955
956 /* Do 1 allocation instead of 2 separate ones for Rx and Tx BD rings */
957 priv->rxbd = dmam_alloc_coherent(dev, RX_RING_SZ + TX_RING_SZ,
958 &priv->rxbd_dma, GFP_KERNEL);
959
960 if (!priv->rxbd) {
961 dev_err(dev, "failed to allocate data buffers\n");
962 err = -ENOMEM;
963 goto out_clken;
964 }
965
966 priv->txbd = priv->rxbd + RX_BD_NUM;
967
968 priv->txbd_dma = priv->rxbd_dma + RX_RING_SZ;
969 dev_dbg(dev, "EMAC Device addr: Rx Ring [0x%x], Tx Ring[%x]\n",
970 (unsigned int)priv->rxbd_dma, (unsigned int)priv->txbd_dma);
971
972 err = arc_mdio_probe(priv);
973 if (err) {
974 dev_err(dev, "failed to probe MII bus\n");
975 goto out_clken;
976 }
977
978 phydev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
979 interface);
980 if (!phydev) {
981 dev_err(dev, "of_phy_connect() failed\n");
982 err = -ENODEV;
983 goto out_mdio;
984 }
985
986 dev_info(dev, "connected to %s phy with id 0x%x\n",
987 phydev->drv->name, phydev->phy_id);
988
989 netif_napi_add_weight(ndev, &priv->napi, arc_emac_poll,
990 ARC_EMAC_NAPI_WEIGHT);
991
992 err = register_netdev(ndev);
993 if (err) {
994 dev_err(dev, "failed to register network device\n");
995 goto out_netif_api;
996 }
997
998 of_node_put(phy_node);
999 return 0;
1000
1001out_netif_api:
1002 netif_napi_del(&priv->napi);
1003 phy_disconnect(phydev);
1004out_mdio:
1005 arc_mdio_remove(priv);
1006out_clken:
1007 if (priv->clk)
1008 clk_disable_unprepare(priv->clk);
1009out_put_node:
1010 of_node_put(phy_node);
1011
1012 return err;
1013}
1014EXPORT_SYMBOL_GPL(arc_emac_probe);
1015
1016void arc_emac_remove(struct net_device *ndev)
1017{
1018 struct arc_emac_priv *priv = netdev_priv(ndev);
1019
1020 phy_disconnect(ndev->phydev);
1021 arc_mdio_remove(priv);
1022 unregister_netdev(ndev);
1023 netif_napi_del(&priv->napi);
1024
1025 if (!IS_ERR(priv->clk))
1026 clk_disable_unprepare(priv->clk);
1027}
1028EXPORT_SYMBOL_GPL(arc_emac_remove);
1029
1030MODULE_AUTHOR("Alexey Brodkin <abrodkin@synopsys.com>");
1031MODULE_DESCRIPTION("ARC EMAC driver");
1032MODULE_LICENSE("GPL");
1/*
2 * Copyright (C) 2004-2013 Synopsys, Inc. (www.synopsys.com)
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * Driver for the ARC EMAC 10100 (hardware revision 5)
9 *
10 * Contributors:
11 * Amit Bhor
12 * Sameer Dhavale
13 * Vineet Gupta
14 */
15
16#include <linux/crc32.h>
17#include <linux/etherdevice.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/module.h>
21#include <linux/of_address.h>
22#include <linux/of_irq.h>
23#include <linux/of_mdio.h>
24#include <linux/of_net.h>
25#include <linux/of_platform.h>
26
27#include "emac.h"
28
29/**
30 * arc_emac_tx_avail - Return the number of available slots in the tx ring.
31 * @priv: Pointer to ARC EMAC private data structure.
32 *
33 * returns: the number of slots available for transmission in tx the ring.
34 */
35static inline int arc_emac_tx_avail(struct arc_emac_priv *priv)
36{
37 return (priv->txbd_dirty + TX_BD_NUM - priv->txbd_curr - 1) % TX_BD_NUM;
38}
39
40/**
41 * arc_emac_adjust_link - Adjust the PHY link duplex.
42 * @ndev: Pointer to the net_device structure.
43 *
44 * This function is called to change the duplex setting after auto negotiation
45 * is done by the PHY.
46 */
47static void arc_emac_adjust_link(struct net_device *ndev)
48{
49 struct arc_emac_priv *priv = netdev_priv(ndev);
50 struct phy_device *phy_dev = ndev->phydev;
51 unsigned int reg, state_changed = 0;
52
53 if (priv->link != phy_dev->link) {
54 priv->link = phy_dev->link;
55 state_changed = 1;
56 }
57
58 if (priv->speed != phy_dev->speed) {
59 priv->speed = phy_dev->speed;
60 state_changed = 1;
61 if (priv->set_mac_speed)
62 priv->set_mac_speed(priv, priv->speed);
63 }
64
65 if (priv->duplex != phy_dev->duplex) {
66 reg = arc_reg_get(priv, R_CTRL);
67
68 if (phy_dev->duplex == DUPLEX_FULL)
69 reg |= ENFL_MASK;
70 else
71 reg &= ~ENFL_MASK;
72
73 arc_reg_set(priv, R_CTRL, reg);
74 priv->duplex = phy_dev->duplex;
75 state_changed = 1;
76 }
77
78 if (state_changed)
79 phy_print_status(phy_dev);
80}
81
82/**
83 * arc_emac_get_drvinfo - Get EMAC driver information.
84 * @ndev: Pointer to net_device structure.
85 * @info: Pointer to ethtool_drvinfo structure.
86 *
87 * This implements ethtool command for getting the driver information.
88 * Issue "ethtool -i ethX" under linux prompt to execute this function.
89 */
90static void arc_emac_get_drvinfo(struct net_device *ndev,
91 struct ethtool_drvinfo *info)
92{
93 struct arc_emac_priv *priv = netdev_priv(ndev);
94
95 strlcpy(info->driver, priv->drv_name, sizeof(info->driver));
96 strlcpy(info->version, priv->drv_version, sizeof(info->version));
97}
98
99static const struct ethtool_ops arc_emac_ethtool_ops = {
100 .get_drvinfo = arc_emac_get_drvinfo,
101 .get_link = ethtool_op_get_link,
102 .get_link_ksettings = phy_ethtool_get_link_ksettings,
103 .set_link_ksettings = phy_ethtool_set_link_ksettings,
104};
105
106#define FIRST_OR_LAST_MASK (FIRST_MASK | LAST_MASK)
107
108/**
109 * arc_emac_tx_clean - clears processed by EMAC Tx BDs.
110 * @ndev: Pointer to the network device.
111 */
112static void arc_emac_tx_clean(struct net_device *ndev)
113{
114 struct arc_emac_priv *priv = netdev_priv(ndev);
115 struct net_device_stats *stats = &ndev->stats;
116 unsigned int i;
117
118 for (i = 0; i < TX_BD_NUM; i++) {
119 unsigned int *txbd_dirty = &priv->txbd_dirty;
120 struct arc_emac_bd *txbd = &priv->txbd[*txbd_dirty];
121 struct buffer_state *tx_buff = &priv->tx_buff[*txbd_dirty];
122 struct sk_buff *skb = tx_buff->skb;
123 unsigned int info = le32_to_cpu(txbd->info);
124
125 if ((info & FOR_EMAC) || !txbd->data || !skb)
126 break;
127
128 if (unlikely(info & (DROP | DEFR | LTCL | UFLO))) {
129 stats->tx_errors++;
130 stats->tx_dropped++;
131
132 if (info & DEFR)
133 stats->tx_carrier_errors++;
134
135 if (info & LTCL)
136 stats->collisions++;
137
138 if (info & UFLO)
139 stats->tx_fifo_errors++;
140 } else if (likely(info & FIRST_OR_LAST_MASK)) {
141 stats->tx_packets++;
142 stats->tx_bytes += skb->len;
143 }
144
145 dma_unmap_single(&ndev->dev, dma_unmap_addr(tx_buff, addr),
146 dma_unmap_len(tx_buff, len), DMA_TO_DEVICE);
147
148 /* return the sk_buff to system */
149 dev_kfree_skb_irq(skb);
150
151 txbd->data = 0;
152 txbd->info = 0;
153 tx_buff->skb = NULL;
154
155 *txbd_dirty = (*txbd_dirty + 1) % TX_BD_NUM;
156 }
157
158 /* Ensure that txbd_dirty is visible to tx() before checking
159 * for queue stopped.
160 */
161 smp_mb();
162
163 if (netif_queue_stopped(ndev) && arc_emac_tx_avail(priv))
164 netif_wake_queue(ndev);
165}
166
167/**
168 * arc_emac_rx - processing of Rx packets.
169 * @ndev: Pointer to the network device.
170 * @budget: How many BDs to process on 1 call.
171 *
172 * returns: Number of processed BDs
173 *
174 * Iterate through Rx BDs and deliver received packages to upper layer.
175 */
176static int arc_emac_rx(struct net_device *ndev, int budget)
177{
178 struct arc_emac_priv *priv = netdev_priv(ndev);
179 unsigned int work_done;
180
181 for (work_done = 0; work_done < budget; work_done++) {
182 unsigned int *last_rx_bd = &priv->last_rx_bd;
183 struct net_device_stats *stats = &ndev->stats;
184 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd];
185 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd];
186 unsigned int pktlen, info = le32_to_cpu(rxbd->info);
187 struct sk_buff *skb;
188 dma_addr_t addr;
189
190 if (unlikely((info & OWN_MASK) == FOR_EMAC))
191 break;
192
193 /* Make a note that we saw a packet at this BD.
194 * So next time, driver starts from this + 1
195 */
196 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM;
197
198 if (unlikely((info & FIRST_OR_LAST_MASK) !=
199 FIRST_OR_LAST_MASK)) {
200 /* We pre-allocate buffers of MTU size so incoming
201 * packets won't be split/chained.
202 */
203 if (net_ratelimit())
204 netdev_err(ndev, "incomplete packet received\n");
205
206 /* Return ownership to EMAC */
207 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
208 stats->rx_errors++;
209 stats->rx_length_errors++;
210 continue;
211 }
212
213 pktlen = info & LEN_MASK;
214 stats->rx_packets++;
215 stats->rx_bytes += pktlen;
216 skb = rx_buff->skb;
217 skb_put(skb, pktlen);
218 skb->dev = ndev;
219 skb->protocol = eth_type_trans(skb, ndev);
220
221 dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr),
222 dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE);
223
224 /* Prepare the BD for next cycle */
225 rx_buff->skb = netdev_alloc_skb_ip_align(ndev,
226 EMAC_BUFFER_SIZE);
227 if (unlikely(!rx_buff->skb)) {
228 stats->rx_errors++;
229 /* Because receive_skb is below, increment rx_dropped */
230 stats->rx_dropped++;
231 continue;
232 }
233
234 /* receive_skb only if new skb was allocated to avoid holes */
235 netif_receive_skb(skb);
236
237 addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data,
238 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE);
239 if (dma_mapping_error(&ndev->dev, addr)) {
240 if (net_ratelimit())
241 netdev_err(ndev, "cannot dma map\n");
242 dev_kfree_skb(rx_buff->skb);
243 stats->rx_errors++;
244 continue;
245 }
246 dma_unmap_addr_set(rx_buff, addr, addr);
247 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE);
248
249 rxbd->data = cpu_to_le32(addr);
250
251 /* Make sure pointer to data buffer is set */
252 wmb();
253
254 /* Return ownership to EMAC */
255 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
256 }
257
258 return work_done;
259}
260
261/**
262 * arc_emac_poll - NAPI poll handler.
263 * @napi: Pointer to napi_struct structure.
264 * @budget: How many BDs to process on 1 call.
265 *
266 * returns: Number of processed BDs
267 */
268static int arc_emac_poll(struct napi_struct *napi, int budget)
269{
270 struct net_device *ndev = napi->dev;
271 struct arc_emac_priv *priv = netdev_priv(ndev);
272 unsigned int work_done;
273
274 arc_emac_tx_clean(ndev);
275
276 work_done = arc_emac_rx(ndev, budget);
277 if (work_done < budget) {
278 napi_complete(napi);
279 arc_reg_or(priv, R_ENABLE, RXINT_MASK | TXINT_MASK);
280 }
281
282 return work_done;
283}
284
285/**
286 * arc_emac_intr - Global interrupt handler for EMAC.
287 * @irq: irq number.
288 * @dev_instance: device instance.
289 *
290 * returns: IRQ_HANDLED for all cases.
291 *
292 * ARC EMAC has only 1 interrupt line, and depending on bits raised in
293 * STATUS register we may tell what is a reason for interrupt to fire.
294 */
295static irqreturn_t arc_emac_intr(int irq, void *dev_instance)
296{
297 struct net_device *ndev = dev_instance;
298 struct arc_emac_priv *priv = netdev_priv(ndev);
299 struct net_device_stats *stats = &ndev->stats;
300 unsigned int status;
301
302 status = arc_reg_get(priv, R_STATUS);
303 status &= ~MDIO_MASK;
304
305 /* Reset all flags except "MDIO complete" */
306 arc_reg_set(priv, R_STATUS, status);
307
308 if (status & (RXINT_MASK | TXINT_MASK)) {
309 if (likely(napi_schedule_prep(&priv->napi))) {
310 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK);
311 __napi_schedule(&priv->napi);
312 }
313 }
314
315 if (status & ERR_MASK) {
316 /* MSER/RXCR/RXFR/RXFL interrupt fires on corresponding
317 * 8-bit error counter overrun.
318 */
319
320 if (status & MSER_MASK) {
321 stats->rx_missed_errors += 0x100;
322 stats->rx_errors += 0x100;
323 }
324
325 if (status & RXCR_MASK) {
326 stats->rx_crc_errors += 0x100;
327 stats->rx_errors += 0x100;
328 }
329
330 if (status & RXFR_MASK) {
331 stats->rx_frame_errors += 0x100;
332 stats->rx_errors += 0x100;
333 }
334
335 if (status & RXFL_MASK) {
336 stats->rx_over_errors += 0x100;
337 stats->rx_errors += 0x100;
338 }
339 }
340
341 return IRQ_HANDLED;
342}
343
344#ifdef CONFIG_NET_POLL_CONTROLLER
345static void arc_emac_poll_controller(struct net_device *dev)
346{
347 disable_irq(dev->irq);
348 arc_emac_intr(dev->irq, dev);
349 enable_irq(dev->irq);
350}
351#endif
352
353/**
354 * arc_emac_open - Open the network device.
355 * @ndev: Pointer to the network device.
356 *
357 * returns: 0, on success or non-zero error value on failure.
358 *
359 * This function sets the MAC address, requests and enables an IRQ
360 * for the EMAC device and starts the Tx queue.
361 * It also connects to the phy device.
362 */
363static int arc_emac_open(struct net_device *ndev)
364{
365 struct arc_emac_priv *priv = netdev_priv(ndev);
366 struct phy_device *phy_dev = ndev->phydev;
367 int i;
368
369 phy_dev->autoneg = AUTONEG_ENABLE;
370 phy_dev->speed = 0;
371 phy_dev->duplex = 0;
372 phy_dev->advertising &= phy_dev->supported;
373
374 priv->last_rx_bd = 0;
375
376 /* Allocate and set buffers for Rx BD's */
377 for (i = 0; i < RX_BD_NUM; i++) {
378 dma_addr_t addr;
379 unsigned int *last_rx_bd = &priv->last_rx_bd;
380 struct arc_emac_bd *rxbd = &priv->rxbd[*last_rx_bd];
381 struct buffer_state *rx_buff = &priv->rx_buff[*last_rx_bd];
382
383 rx_buff->skb = netdev_alloc_skb_ip_align(ndev,
384 EMAC_BUFFER_SIZE);
385 if (unlikely(!rx_buff->skb))
386 return -ENOMEM;
387
388 addr = dma_map_single(&ndev->dev, (void *)rx_buff->skb->data,
389 EMAC_BUFFER_SIZE, DMA_FROM_DEVICE);
390 if (dma_mapping_error(&ndev->dev, addr)) {
391 netdev_err(ndev, "cannot dma map\n");
392 dev_kfree_skb(rx_buff->skb);
393 return -ENOMEM;
394 }
395 dma_unmap_addr_set(rx_buff, addr, addr);
396 dma_unmap_len_set(rx_buff, len, EMAC_BUFFER_SIZE);
397
398 rxbd->data = cpu_to_le32(addr);
399
400 /* Make sure pointer to data buffer is set */
401 wmb();
402
403 /* Return ownership to EMAC */
404 rxbd->info = cpu_to_le32(FOR_EMAC | EMAC_BUFFER_SIZE);
405
406 *last_rx_bd = (*last_rx_bd + 1) % RX_BD_NUM;
407 }
408
409 priv->txbd_curr = 0;
410 priv->txbd_dirty = 0;
411
412 /* Clean Tx BD's */
413 memset(priv->txbd, 0, TX_RING_SZ);
414
415 /* Initialize logical address filter */
416 arc_reg_set(priv, R_LAFL, 0);
417 arc_reg_set(priv, R_LAFH, 0);
418
419 /* Set BD ring pointers for device side */
420 arc_reg_set(priv, R_RX_RING, (unsigned int)priv->rxbd_dma);
421 arc_reg_set(priv, R_TX_RING, (unsigned int)priv->txbd_dma);
422
423 /* Enable interrupts */
424 arc_reg_set(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK);
425
426 /* Set CONTROL */
427 arc_reg_set(priv, R_CTRL,
428 (RX_BD_NUM << 24) | /* RX BD table length */
429 (TX_BD_NUM << 16) | /* TX BD table length */
430 TXRN_MASK | RXRN_MASK);
431
432 napi_enable(&priv->napi);
433
434 /* Enable EMAC */
435 arc_reg_or(priv, R_CTRL, EN_MASK);
436
437 phy_start_aneg(ndev->phydev);
438
439 netif_start_queue(ndev);
440
441 return 0;
442}
443
444/**
445 * arc_emac_set_rx_mode - Change the receive filtering mode.
446 * @ndev: Pointer to the network device.
447 *
448 * This function enables/disables promiscuous or all-multicast mode
449 * and updates the multicast filtering list of the network device.
450 */
451static void arc_emac_set_rx_mode(struct net_device *ndev)
452{
453 struct arc_emac_priv *priv = netdev_priv(ndev);
454
455 if (ndev->flags & IFF_PROMISC) {
456 arc_reg_or(priv, R_CTRL, PROM_MASK);
457 } else {
458 arc_reg_clr(priv, R_CTRL, PROM_MASK);
459
460 if (ndev->flags & IFF_ALLMULTI) {
461 arc_reg_set(priv, R_LAFL, ~0);
462 arc_reg_set(priv, R_LAFH, ~0);
463 } else if (ndev->flags & IFF_MULTICAST) {
464 struct netdev_hw_addr *ha;
465 unsigned int filter[2] = { 0, 0 };
466 int bit;
467
468 netdev_for_each_mc_addr(ha, ndev) {
469 bit = ether_crc_le(ETH_ALEN, ha->addr) >> 26;
470 filter[bit >> 5] |= 1 << (bit & 31);
471 }
472
473 arc_reg_set(priv, R_LAFL, filter[0]);
474 arc_reg_set(priv, R_LAFH, filter[1]);
475 } else {
476 arc_reg_set(priv, R_LAFL, 0);
477 arc_reg_set(priv, R_LAFH, 0);
478 }
479 }
480}
481
482/**
483 * arc_free_tx_queue - free skb from tx queue
484 * @ndev: Pointer to the network device.
485 *
486 * This function must be called while EMAC disable
487 */
488static void arc_free_tx_queue(struct net_device *ndev)
489{
490 struct arc_emac_priv *priv = netdev_priv(ndev);
491 unsigned int i;
492
493 for (i = 0; i < TX_BD_NUM; i++) {
494 struct arc_emac_bd *txbd = &priv->txbd[i];
495 struct buffer_state *tx_buff = &priv->tx_buff[i];
496
497 if (tx_buff->skb) {
498 dma_unmap_single(&ndev->dev,
499 dma_unmap_addr(tx_buff, addr),
500 dma_unmap_len(tx_buff, len),
501 DMA_TO_DEVICE);
502
503 /* return the sk_buff to system */
504 dev_kfree_skb_irq(tx_buff->skb);
505 }
506
507 txbd->info = 0;
508 txbd->data = 0;
509 tx_buff->skb = NULL;
510 }
511}
512
513/**
514 * arc_free_rx_queue - free skb from rx queue
515 * @ndev: Pointer to the network device.
516 *
517 * This function must be called while EMAC disable
518 */
519static void arc_free_rx_queue(struct net_device *ndev)
520{
521 struct arc_emac_priv *priv = netdev_priv(ndev);
522 unsigned int i;
523
524 for (i = 0; i < RX_BD_NUM; i++) {
525 struct arc_emac_bd *rxbd = &priv->rxbd[i];
526 struct buffer_state *rx_buff = &priv->rx_buff[i];
527
528 if (rx_buff->skb) {
529 dma_unmap_single(&ndev->dev,
530 dma_unmap_addr(rx_buff, addr),
531 dma_unmap_len(rx_buff, len),
532 DMA_FROM_DEVICE);
533
534 /* return the sk_buff to system */
535 dev_kfree_skb_irq(rx_buff->skb);
536 }
537
538 rxbd->info = 0;
539 rxbd->data = 0;
540 rx_buff->skb = NULL;
541 }
542}
543
544/**
545 * arc_emac_stop - Close the network device.
546 * @ndev: Pointer to the network device.
547 *
548 * This function stops the Tx queue, disables interrupts and frees the IRQ for
549 * the EMAC device.
550 * It also disconnects the PHY device associated with the EMAC device.
551 */
552static int arc_emac_stop(struct net_device *ndev)
553{
554 struct arc_emac_priv *priv = netdev_priv(ndev);
555
556 napi_disable(&priv->napi);
557 netif_stop_queue(ndev);
558
559 /* Disable interrupts */
560 arc_reg_clr(priv, R_ENABLE, RXINT_MASK | TXINT_MASK | ERR_MASK);
561
562 /* Disable EMAC */
563 arc_reg_clr(priv, R_CTRL, EN_MASK);
564
565 /* Return the sk_buff to system */
566 arc_free_tx_queue(ndev);
567 arc_free_rx_queue(ndev);
568
569 return 0;
570}
571
572/**
573 * arc_emac_stats - Get system network statistics.
574 * @ndev: Pointer to net_device structure.
575 *
576 * Returns the address of the device statistics structure.
577 * Statistics are updated in interrupt handler.
578 */
579static struct net_device_stats *arc_emac_stats(struct net_device *ndev)
580{
581 struct arc_emac_priv *priv = netdev_priv(ndev);
582 struct net_device_stats *stats = &ndev->stats;
583 unsigned long miss, rxerr;
584 u8 rxcrc, rxfram, rxoflow;
585
586 rxerr = arc_reg_get(priv, R_RXERR);
587 miss = arc_reg_get(priv, R_MISS);
588
589 rxcrc = rxerr;
590 rxfram = rxerr >> 8;
591 rxoflow = rxerr >> 16;
592
593 stats->rx_errors += miss;
594 stats->rx_errors += rxcrc + rxfram + rxoflow;
595
596 stats->rx_over_errors += rxoflow;
597 stats->rx_frame_errors += rxfram;
598 stats->rx_crc_errors += rxcrc;
599 stats->rx_missed_errors += miss;
600
601 return stats;
602}
603
604/**
605 * arc_emac_tx - Starts the data transmission.
606 * @skb: sk_buff pointer that contains data to be Transmitted.
607 * @ndev: Pointer to net_device structure.
608 *
609 * returns: NETDEV_TX_OK, on success
610 * NETDEV_TX_BUSY, if any of the descriptors are not free.
611 *
612 * This function is invoked from upper layers to initiate transmission.
613 */
614static int arc_emac_tx(struct sk_buff *skb, struct net_device *ndev)
615{
616 struct arc_emac_priv *priv = netdev_priv(ndev);
617 unsigned int len, *txbd_curr = &priv->txbd_curr;
618 struct net_device_stats *stats = &ndev->stats;
619 __le32 *info = &priv->txbd[*txbd_curr].info;
620 dma_addr_t addr;
621
622 if (skb_padto(skb, ETH_ZLEN))
623 return NETDEV_TX_OK;
624
625 len = max_t(unsigned int, ETH_ZLEN, skb->len);
626
627 if (unlikely(!arc_emac_tx_avail(priv))) {
628 netif_stop_queue(ndev);
629 netdev_err(ndev, "BUG! Tx Ring full when queue awake!\n");
630 return NETDEV_TX_BUSY;
631 }
632
633 addr = dma_map_single(&ndev->dev, (void *)skb->data, len,
634 DMA_TO_DEVICE);
635
636 if (unlikely(dma_mapping_error(&ndev->dev, addr))) {
637 stats->tx_dropped++;
638 stats->tx_errors++;
639 dev_kfree_skb_any(skb);
640 return NETDEV_TX_OK;
641 }
642 dma_unmap_addr_set(&priv->tx_buff[*txbd_curr], addr, addr);
643 dma_unmap_len_set(&priv->tx_buff[*txbd_curr], len, len);
644
645 priv->txbd[*txbd_curr].data = cpu_to_le32(addr);
646
647 /* Make sure pointer to data buffer is set */
648 wmb();
649
650 skb_tx_timestamp(skb);
651
652 *info = cpu_to_le32(FOR_EMAC | FIRST_OR_LAST_MASK | len);
653
654 /* Make sure info word is set */
655 wmb();
656
657 priv->tx_buff[*txbd_curr].skb = skb;
658
659 /* Increment index to point to the next BD */
660 *txbd_curr = (*txbd_curr + 1) % TX_BD_NUM;
661
662 /* Ensure that tx_clean() sees the new txbd_curr before
663 * checking the queue status. This prevents an unneeded wake
664 * of the queue in tx_clean().
665 */
666 smp_mb();
667
668 if (!arc_emac_tx_avail(priv)) {
669 netif_stop_queue(ndev);
670 /* Refresh tx_dirty */
671 smp_mb();
672 if (arc_emac_tx_avail(priv))
673 netif_start_queue(ndev);
674 }
675
676 arc_reg_set(priv, R_STATUS, TXPL_MASK);
677
678 return NETDEV_TX_OK;
679}
680
681static void arc_emac_set_address_internal(struct net_device *ndev)
682{
683 struct arc_emac_priv *priv = netdev_priv(ndev);
684 unsigned int addr_low, addr_hi;
685
686 addr_low = le32_to_cpu(*(__le32 *)&ndev->dev_addr[0]);
687 addr_hi = le16_to_cpu(*(__le16 *)&ndev->dev_addr[4]);
688
689 arc_reg_set(priv, R_ADDRL, addr_low);
690 arc_reg_set(priv, R_ADDRH, addr_hi);
691}
692
693/**
694 * arc_emac_set_address - Set the MAC address for this device.
695 * @ndev: Pointer to net_device structure.
696 * @p: 6 byte Address to be written as MAC address.
697 *
698 * This function copies the HW address from the sockaddr structure to the
699 * net_device structure and updates the address in HW.
700 *
701 * returns: -EBUSY if the net device is busy or 0 if the address is set
702 * successfully.
703 */
704static int arc_emac_set_address(struct net_device *ndev, void *p)
705{
706 struct sockaddr *addr = p;
707
708 if (netif_running(ndev))
709 return -EBUSY;
710
711 if (!is_valid_ether_addr(addr->sa_data))
712 return -EADDRNOTAVAIL;
713
714 memcpy(ndev->dev_addr, addr->sa_data, ndev->addr_len);
715
716 arc_emac_set_address_internal(ndev);
717
718 return 0;
719}
720
721static const struct net_device_ops arc_emac_netdev_ops = {
722 .ndo_open = arc_emac_open,
723 .ndo_stop = arc_emac_stop,
724 .ndo_start_xmit = arc_emac_tx,
725 .ndo_set_mac_address = arc_emac_set_address,
726 .ndo_get_stats = arc_emac_stats,
727 .ndo_set_rx_mode = arc_emac_set_rx_mode,
728#ifdef CONFIG_NET_POLL_CONTROLLER
729 .ndo_poll_controller = arc_emac_poll_controller,
730#endif
731};
732
733int arc_emac_probe(struct net_device *ndev, int interface)
734{
735 struct device *dev = ndev->dev.parent;
736 struct resource res_regs;
737 struct device_node *phy_node;
738 struct phy_device *phydev = NULL;
739 struct arc_emac_priv *priv;
740 const char *mac_addr;
741 unsigned int id, clock_frequency, irq;
742 int err;
743
744 /* Get PHY from device tree */
745 phy_node = of_parse_phandle(dev->of_node, "phy", 0);
746 if (!phy_node) {
747 dev_err(dev, "failed to retrieve phy description from device tree\n");
748 return -ENODEV;
749 }
750
751 /* Get EMAC registers base address from device tree */
752 err = of_address_to_resource(dev->of_node, 0, &res_regs);
753 if (err) {
754 dev_err(dev, "failed to retrieve registers base from device tree\n");
755 err = -ENODEV;
756 goto out_put_node;
757 }
758
759 /* Get IRQ from device tree */
760 irq = irq_of_parse_and_map(dev->of_node, 0);
761 if (!irq) {
762 dev_err(dev, "failed to retrieve <irq> value from device tree\n");
763 err = -ENODEV;
764 goto out_put_node;
765 }
766
767 ndev->netdev_ops = &arc_emac_netdev_ops;
768 ndev->ethtool_ops = &arc_emac_ethtool_ops;
769 ndev->watchdog_timeo = TX_TIMEOUT;
770
771 priv = netdev_priv(ndev);
772 priv->dev = dev;
773
774 priv->regs = devm_ioremap_resource(dev, &res_regs);
775 if (IS_ERR(priv->regs)) {
776 err = PTR_ERR(priv->regs);
777 goto out_put_node;
778 }
779
780 dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs);
781
782 if (priv->clk) {
783 err = clk_prepare_enable(priv->clk);
784 if (err) {
785 dev_err(dev, "failed to enable clock\n");
786 goto out_put_node;
787 }
788
789 clock_frequency = clk_get_rate(priv->clk);
790 } else {
791 /* Get CPU clock frequency from device tree */
792 if (of_property_read_u32(dev->of_node, "clock-frequency",
793 &clock_frequency)) {
794 dev_err(dev, "failed to retrieve <clock-frequency> from device tree\n");
795 err = -EINVAL;
796 goto out_put_node;
797 }
798 }
799
800 id = arc_reg_get(priv, R_ID);
801
802 /* Check for EMAC revision 5 or 7, magic number */
803 if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
804 dev_err(dev, "ARC EMAC not detected, id=0x%x\n", id);
805 err = -ENODEV;
806 goto out_clken;
807 }
808 dev_info(dev, "ARC EMAC detected with id: 0x%x\n", id);
809
810 /* Set poll rate so that it polls every 1 ms */
811 arc_reg_set(priv, R_POLLRATE, clock_frequency / 1000000);
812
813 ndev->irq = irq;
814 dev_info(dev, "IRQ is %d\n", ndev->irq);
815
816 /* Register interrupt handler for device */
817 err = devm_request_irq(dev, ndev->irq, arc_emac_intr, 0,
818 ndev->name, ndev);
819 if (err) {
820 dev_err(dev, "could not allocate IRQ\n");
821 goto out_clken;
822 }
823
824 /* Get MAC address from device tree */
825 mac_addr = of_get_mac_address(dev->of_node);
826
827 if (mac_addr)
828 memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
829 else
830 eth_hw_addr_random(ndev);
831
832 arc_emac_set_address_internal(ndev);
833 dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
834
835 /* Do 1 allocation instead of 2 separate ones for Rx and Tx BD rings */
836 priv->rxbd = dmam_alloc_coherent(dev, RX_RING_SZ + TX_RING_SZ,
837 &priv->rxbd_dma, GFP_KERNEL);
838
839 if (!priv->rxbd) {
840 dev_err(dev, "failed to allocate data buffers\n");
841 err = -ENOMEM;
842 goto out_clken;
843 }
844
845 priv->txbd = priv->rxbd + RX_BD_NUM;
846
847 priv->txbd_dma = priv->rxbd_dma + RX_RING_SZ;
848 dev_dbg(dev, "EMAC Device addr: Rx Ring [0x%x], Tx Ring[%x]\n",
849 (unsigned int)priv->rxbd_dma, (unsigned int)priv->txbd_dma);
850
851 err = arc_mdio_probe(priv);
852 if (err) {
853 dev_err(dev, "failed to probe MII bus\n");
854 goto out_clken;
855 }
856
857 phydev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
858 interface);
859 if (!phydev) {
860 dev_err(dev, "of_phy_connect() failed\n");
861 err = -ENODEV;
862 goto out_mdio;
863 }
864
865 dev_info(dev, "connected to %s phy with id 0x%x\n",
866 phydev->drv->name, phydev->phy_id);
867
868 netif_napi_add(ndev, &priv->napi, arc_emac_poll, ARC_EMAC_NAPI_WEIGHT);
869
870 err = register_netdev(ndev);
871 if (err) {
872 dev_err(dev, "failed to register network device\n");
873 goto out_netif_api;
874 }
875
876 of_node_put(phy_node);
877 return 0;
878
879out_netif_api:
880 netif_napi_del(&priv->napi);
881 phy_disconnect(phydev);
882out_mdio:
883 arc_mdio_remove(priv);
884out_clken:
885 if (priv->clk)
886 clk_disable_unprepare(priv->clk);
887out_put_node:
888 of_node_put(phy_node);
889
890 return err;
891}
892EXPORT_SYMBOL_GPL(arc_emac_probe);
893
894int arc_emac_remove(struct net_device *ndev)
895{
896 struct arc_emac_priv *priv = netdev_priv(ndev);
897
898 phy_disconnect(ndev->phydev);
899 arc_mdio_remove(priv);
900 unregister_netdev(ndev);
901 netif_napi_del(&priv->napi);
902
903 if (!IS_ERR(priv->clk))
904 clk_disable_unprepare(priv->clk);
905
906 return 0;
907}
908EXPORT_SYMBOL_GPL(arc_emac_remove);
909
910MODULE_AUTHOR("Alexey Brodkin <abrodkin@synopsys.com>");
911MODULE_DESCRIPTION("ARC EMAC driver");
912MODULE_LICENSE("GPL");