1 /* Synopsys DesignWare Core Enterprise Ethernet (XLGMAC) Driver
2  *
3  * Copyright (c) 2017 Synopsys, Inc. (www.synopsys.com)
4  *
5  * This program is dual-licensed; you may select either version 2 of
6  * the GNU General Public License ("GPL") or BSD license ("BSD").
7  *
8  * This Synopsys DWC XLGMAC software driver and associated documentation
9  * (hereinafter the "Software") is an unsupported proprietary work of
10  * Synopsys, Inc. unless otherwise expressly agreed to in writing between
11  * Synopsys and you. The Software IS NOT an item of Licensed Software or a
12  * Licensed Product under any End User Software License Agreement or
13  * Agreement for Licensed Products with Synopsys or any supplement thereto.
14  * Synopsys is a registered trademark of Synopsys, Inc. Other names included
15  * in the SOFTWARE may be the trademarks of their respective owners.
16  */
17 
18 #include <linux/netdevice.h>
19 #include <linux/tcp.h>
20 #include <linux/interrupt.h>
21 
22 #include "dwc-xlgmac.h"
23 #include "dwc-xlgmac-reg.h"
24 
25 static int xlgmac_one_poll(struct napi_struct *, int);
26 static int xlgmac_all_poll(struct napi_struct *, int);
27 
28 static inline unsigned int xlgmac_tx_avail_desc(struct xlgmac_ring *ring)
29 {
30 	return (ring->dma_desc_count - (ring->cur - ring->dirty));
31 }
32 
33 static inline unsigned int xlgmac_rx_dirty_desc(struct xlgmac_ring *ring)
34 {
35 	return (ring->cur - ring->dirty);
36 }
37 
38 static int xlgmac_maybe_stop_tx_queue(
39 			struct xlgmac_channel *channel,
40 			struct xlgmac_ring *ring,
41 			unsigned int count)
42 {
43 	struct xlgmac_pdata *pdata = channel->pdata;
44 
45 	if (count > xlgmac_tx_avail_desc(ring)) {
46 		netif_info(pdata, drv, pdata->netdev,
47 			   "Tx queue stopped, not enough descriptors available\n");
48 		netif_stop_subqueue(pdata->netdev, channel->queue_index);
49 		ring->tx.queue_stopped = 1;
50 
51 		/* If we haven't notified the hardware because of xmit_more
52 		 * support, tell it now
53 		 */
54 		if (ring->tx.xmit_more)
55 			pdata->hw_ops.tx_start_xmit(channel, ring);
56 
57 		return NETDEV_TX_BUSY;
58 	}
59 
60 	return 0;
61 }
62 
63 static void xlgmac_prep_vlan(struct sk_buff *skb,
64 			     struct xlgmac_pkt_info *pkt_info)
65 {
66 	if (skb_vlan_tag_present(skb))
67 		pkt_info->vlan_ctag = skb_vlan_tag_get(skb);
68 }
69 
70 static int xlgmac_prep_tso(struct sk_buff *skb,
71 			   struct xlgmac_pkt_info *pkt_info)
72 {
73 	int ret;
74 
75 	if (!XLGMAC_GET_REG_BITS(pkt_info->attributes,
76 				 TX_PACKET_ATTRIBUTES_TSO_ENABLE_POS,
77 				 TX_PACKET_ATTRIBUTES_TSO_ENABLE_LEN))
78 		return 0;
79 
80 	ret = skb_cow_head(skb, 0);
81 	if (ret)
82 		return ret;
83 
84 	pkt_info->header_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
85 	pkt_info->tcp_header_len = tcp_hdrlen(skb);
86 	pkt_info->tcp_payload_len = skb->len - pkt_info->header_len;
87 	pkt_info->mss = skb_shinfo(skb)->gso_size;
88 
89 	XLGMAC_PR("header_len=%u\n", pkt_info->header_len);
90 	XLGMAC_PR("tcp_header_len=%u, tcp_payload_len=%u\n",
91 		  pkt_info->tcp_header_len, pkt_info->tcp_payload_len);
92 	XLGMAC_PR("mss=%u\n", pkt_info->mss);
93 
94 	/* Update the number of packets that will ultimately be transmitted
95 	 * along with the extra bytes for each extra packet
96 	 */
97 	pkt_info->tx_packets = skb_shinfo(skb)->gso_segs;
98 	pkt_info->tx_bytes += (pkt_info->tx_packets - 1) * pkt_info->header_len;
99 
100 	return 0;
101 }
102 
103 static int xlgmac_is_tso(struct sk_buff *skb)
104 {
105 	if (skb->ip_summed != CHECKSUM_PARTIAL)
106 		return 0;
107 
108 	if (!skb_is_gso(skb))
109 		return 0;
110 
111 	return 1;
112 }
113 
114 static void xlgmac_prep_tx_pkt(struct xlgmac_pdata *pdata,
115 			       struct xlgmac_ring *ring,
116 			       struct sk_buff *skb,
117 			       struct xlgmac_pkt_info *pkt_info)
118 {
119 	skb_frag_t *frag;
120 	unsigned int context_desc;
121 	unsigned int len;
122 	unsigned int i;
123 
124 	pkt_info->skb = skb;
125 
126 	context_desc = 0;
127 	pkt_info->desc_count = 0;
128 
129 	pkt_info->tx_packets = 1;
130 	pkt_info->tx_bytes = skb->len;
131 
132 	if (xlgmac_is_tso(skb)) {
133 		/* TSO requires an extra descriptor if mss is different */
134 		if (skb_shinfo(skb)->gso_size != ring->tx.cur_mss) {
135 			context_desc = 1;
136 			pkt_info->desc_count++;
137 		}
138 
139 		/* TSO requires an extra descriptor for TSO header */
140 		pkt_info->desc_count++;
141 
142 		pkt_info->attributes = XLGMAC_SET_REG_BITS(
143 					pkt_info->attributes,
144 					TX_PACKET_ATTRIBUTES_TSO_ENABLE_POS,
145 					TX_PACKET_ATTRIBUTES_TSO_ENABLE_LEN,
146 					1);
147 		pkt_info->attributes = XLGMAC_SET_REG_BITS(
148 					pkt_info->attributes,
149 					TX_PACKET_ATTRIBUTES_CSUM_ENABLE_POS,
150 					TX_PACKET_ATTRIBUTES_CSUM_ENABLE_LEN,
151 					1);
152 	} else if (skb->ip_summed == CHECKSUM_PARTIAL)
153 		pkt_info->attributes = XLGMAC_SET_REG_BITS(
154 					pkt_info->attributes,
155 					TX_PACKET_ATTRIBUTES_CSUM_ENABLE_POS,
156 					TX_PACKET_ATTRIBUTES_CSUM_ENABLE_LEN,
157 					1);
158 
159 	if (skb_vlan_tag_present(skb)) {
160 		/* VLAN requires an extra descriptor if tag is different */
161 		if (skb_vlan_tag_get(skb) != ring->tx.cur_vlan_ctag)
162 			/* We can share with the TSO context descriptor */
163 			if (!context_desc) {
164 				context_desc = 1;
165 				pkt_info->desc_count++;
166 			}
167 
168 		pkt_info->attributes = XLGMAC_SET_REG_BITS(
169 					pkt_info->attributes,
170 					TX_PACKET_ATTRIBUTES_VLAN_CTAG_POS,
171 					TX_PACKET_ATTRIBUTES_VLAN_CTAG_LEN,
172 					1);
173 	}
174 
175 	for (len = skb_headlen(skb); len;) {
176 		pkt_info->desc_count++;
177 		len -= min_t(unsigned int, len, XLGMAC_TX_MAX_BUF_SIZE);
178 	}
179 
180 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
181 		frag = &skb_shinfo(skb)->frags[i];
182 		for (len = skb_frag_size(frag); len; ) {
183 			pkt_info->desc_count++;
184 			len -= min_t(unsigned int, len, XLGMAC_TX_MAX_BUF_SIZE);
185 		}
186 	}
187 }
188 
189 static int xlgmac_calc_rx_buf_size(struct net_device *netdev, unsigned int mtu)
190 {
191 	unsigned int rx_buf_size;
192 
193 	if (mtu > XLGMAC_JUMBO_PACKET_MTU) {
194 		netdev_alert(netdev, "MTU exceeds maximum supported value\n");
195 		return -EINVAL;
196 	}
197 
198 	rx_buf_size = mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
199 	rx_buf_size = clamp_val(rx_buf_size, XLGMAC_RX_MIN_BUF_SIZE, PAGE_SIZE);
200 
201 	rx_buf_size = (rx_buf_size + XLGMAC_RX_BUF_ALIGN - 1) &
202 		      ~(XLGMAC_RX_BUF_ALIGN - 1);
203 
204 	return rx_buf_size;
205 }
206 
207 static void xlgmac_enable_rx_tx_ints(struct xlgmac_pdata *pdata)
208 {
209 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
210 	struct xlgmac_channel *channel;
211 	enum xlgmac_int int_id;
212 	unsigned int i;
213 
214 	channel = pdata->channel_head;
215 	for (i = 0; i < pdata->channel_count; i++, channel++) {
216 		if (channel->tx_ring && channel->rx_ring)
217 			int_id = XLGMAC_INT_DMA_CH_SR_TI_RI;
218 		else if (channel->tx_ring)
219 			int_id = XLGMAC_INT_DMA_CH_SR_TI;
220 		else if (channel->rx_ring)
221 			int_id = XLGMAC_INT_DMA_CH_SR_RI;
222 		else
223 			continue;
224 
225 		hw_ops->enable_int(channel, int_id);
226 	}
227 }
228 
229 static void xlgmac_disable_rx_tx_ints(struct xlgmac_pdata *pdata)
230 {
231 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
232 	struct xlgmac_channel *channel;
233 	enum xlgmac_int int_id;
234 	unsigned int i;
235 
236 	channel = pdata->channel_head;
237 	for (i = 0; i < pdata->channel_count; i++, channel++) {
238 		if (channel->tx_ring && channel->rx_ring)
239 			int_id = XLGMAC_INT_DMA_CH_SR_TI_RI;
240 		else if (channel->tx_ring)
241 			int_id = XLGMAC_INT_DMA_CH_SR_TI;
242 		else if (channel->rx_ring)
243 			int_id = XLGMAC_INT_DMA_CH_SR_RI;
244 		else
245 			continue;
246 
247 		hw_ops->disable_int(channel, int_id);
248 	}
249 }
250 
251 static irqreturn_t xlgmac_isr(int irq, void *data)
252 {
253 	unsigned int dma_isr, dma_ch_isr, mac_isr;
254 	struct xlgmac_pdata *pdata = data;
255 	struct xlgmac_channel *channel;
256 	struct xlgmac_hw_ops *hw_ops;
257 	unsigned int i, ti, ri;
258 
259 	hw_ops = &pdata->hw_ops;
260 
261 	/* The DMA interrupt status register also reports MAC and MTL
262 	 * interrupts. So for polling mode, we just need to check for
263 	 * this register to be non-zero
264 	 */
265 	dma_isr = readl(pdata->mac_regs + DMA_ISR);
266 	if (!dma_isr)
267 		return IRQ_HANDLED;
268 
269 	netif_dbg(pdata, intr, pdata->netdev, "DMA_ISR=%#010x\n", dma_isr);
270 
271 	for (i = 0; i < pdata->channel_count; i++) {
272 		if (!(dma_isr & (1 << i)))
273 			continue;
274 
275 		channel = pdata->channel_head + i;
276 
277 		dma_ch_isr = readl(XLGMAC_DMA_REG(channel, DMA_CH_SR));
278 		netif_dbg(pdata, intr, pdata->netdev, "DMA_CH%u_ISR=%#010x\n",
279 			  i, dma_ch_isr);
280 
281 		/* The TI or RI interrupt bits may still be set even if using
282 		 * per channel DMA interrupts. Check to be sure those are not
283 		 * enabled before using the private data napi structure.
284 		 */
285 		ti = XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TI_POS,
286 					 DMA_CH_SR_TI_LEN);
287 		ri = XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RI_POS,
288 					 DMA_CH_SR_RI_LEN);
289 		if (!pdata->per_channel_irq && (ti || ri)) {
290 			if (napi_schedule_prep(&pdata->napi)) {
291 				/* Disable Tx and Rx interrupts */
292 				xlgmac_disable_rx_tx_ints(pdata);
293 
294 				pdata->stats.napi_poll_isr++;
295 				/* Turn on polling */
296 				__napi_schedule_irqoff(&pdata->napi);
297 			}
298 		}
299 
300 		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TPS_POS,
301 					DMA_CH_SR_TPS_LEN))
302 			pdata->stats.tx_process_stopped++;
303 
304 		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RPS_POS,
305 					DMA_CH_SR_RPS_LEN))
306 			pdata->stats.rx_process_stopped++;
307 
308 		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_TBU_POS,
309 					DMA_CH_SR_TBU_LEN))
310 			pdata->stats.tx_buffer_unavailable++;
311 
312 		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_RBU_POS,
313 					DMA_CH_SR_RBU_LEN))
314 			pdata->stats.rx_buffer_unavailable++;
315 
316 		/* Restart the device on a Fatal Bus Error */
317 		if (XLGMAC_GET_REG_BITS(dma_ch_isr, DMA_CH_SR_FBE_POS,
318 					DMA_CH_SR_FBE_LEN)) {
319 			pdata->stats.fatal_bus_error++;
320 			schedule_work(&pdata->restart_work);
321 		}
322 
323 		/* Clear all interrupt signals */
324 		writel(dma_ch_isr, XLGMAC_DMA_REG(channel, DMA_CH_SR));
325 	}
326 
327 	if (XLGMAC_GET_REG_BITS(dma_isr, DMA_ISR_MACIS_POS,
328 				DMA_ISR_MACIS_LEN)) {
329 		mac_isr = readl(pdata->mac_regs + MAC_ISR);
330 
331 		if (XLGMAC_GET_REG_BITS(mac_isr, MAC_ISR_MMCTXIS_POS,
332 					MAC_ISR_MMCTXIS_LEN))
333 			hw_ops->tx_mmc_int(pdata);
334 
335 		if (XLGMAC_GET_REG_BITS(mac_isr, MAC_ISR_MMCRXIS_POS,
336 					MAC_ISR_MMCRXIS_LEN))
337 			hw_ops->rx_mmc_int(pdata);
338 	}
339 
340 	return IRQ_HANDLED;
341 }
342 
343 static irqreturn_t xlgmac_dma_isr(int irq, void *data)
344 {
345 	struct xlgmac_channel *channel = data;
346 
347 	/* Per channel DMA interrupts are enabled, so we use the per
348 	 * channel napi structure and not the private data napi structure
349 	 */
350 	if (napi_schedule_prep(&channel->napi)) {
351 		/* Disable Tx and Rx interrupts */
352 		disable_irq_nosync(channel->dma_irq);
353 
354 		/* Turn on polling */
355 		__napi_schedule_irqoff(&channel->napi);
356 	}
357 
358 	return IRQ_HANDLED;
359 }
360 
361 static void xlgmac_tx_timer(struct timer_list *t)
362 {
363 	struct xlgmac_channel *channel = from_timer(channel, t, tx_timer);
364 	struct xlgmac_pdata *pdata = channel->pdata;
365 	struct napi_struct *napi;
366 
367 	napi = (pdata->per_channel_irq) ? &channel->napi : &pdata->napi;
368 
369 	if (napi_schedule_prep(napi)) {
370 		/* Disable Tx and Rx interrupts */
371 		if (pdata->per_channel_irq)
372 			disable_irq_nosync(channel->dma_irq);
373 		else
374 			xlgmac_disable_rx_tx_ints(pdata);
375 
376 		pdata->stats.napi_poll_txtimer++;
377 		/* Turn on polling */
378 		__napi_schedule(napi);
379 	}
380 
381 	channel->tx_timer_active = 0;
382 }
383 
384 static void xlgmac_init_timers(struct xlgmac_pdata *pdata)
385 {
386 	struct xlgmac_channel *channel;
387 	unsigned int i;
388 
389 	channel = pdata->channel_head;
390 	for (i = 0; i < pdata->channel_count; i++, channel++) {
391 		if (!channel->tx_ring)
392 			break;
393 
394 		timer_setup(&channel->tx_timer, xlgmac_tx_timer, 0);
395 	}
396 }
397 
398 static void xlgmac_stop_timers(struct xlgmac_pdata *pdata)
399 {
400 	struct xlgmac_channel *channel;
401 	unsigned int i;
402 
403 	channel = pdata->channel_head;
404 	for (i = 0; i < pdata->channel_count; i++, channel++) {
405 		if (!channel->tx_ring)
406 			break;
407 
408 		del_timer_sync(&channel->tx_timer);
409 	}
410 }
411 
412 static void xlgmac_napi_enable(struct xlgmac_pdata *pdata, unsigned int add)
413 {
414 	struct xlgmac_channel *channel;
415 	unsigned int i;
416 
417 	if (pdata->per_channel_irq) {
418 		channel = pdata->channel_head;
419 		for (i = 0; i < pdata->channel_count; i++, channel++) {
420 			if (add)
421 				netif_napi_add(pdata->netdev, &channel->napi,
422 					       xlgmac_one_poll,
423 					       NAPI_POLL_WEIGHT);
424 
425 			napi_enable(&channel->napi);
426 		}
427 	} else {
428 		if (add)
429 			netif_napi_add(pdata->netdev, &pdata->napi,
430 				       xlgmac_all_poll, NAPI_POLL_WEIGHT);
431 
432 		napi_enable(&pdata->napi);
433 	}
434 }
435 
436 static void xlgmac_napi_disable(struct xlgmac_pdata *pdata, unsigned int del)
437 {
438 	struct xlgmac_channel *channel;
439 	unsigned int i;
440 
441 	if (pdata->per_channel_irq) {
442 		channel = pdata->channel_head;
443 		for (i = 0; i < pdata->channel_count; i++, channel++) {
444 			napi_disable(&channel->napi);
445 
446 			if (del)
447 				netif_napi_del(&channel->napi);
448 		}
449 	} else {
450 		napi_disable(&pdata->napi);
451 
452 		if (del)
453 			netif_napi_del(&pdata->napi);
454 	}
455 }
456 
457 static int xlgmac_request_irqs(struct xlgmac_pdata *pdata)
458 {
459 	struct net_device *netdev = pdata->netdev;
460 	struct xlgmac_channel *channel;
461 	unsigned int i;
462 	int ret;
463 
464 	ret = devm_request_irq(pdata->dev, pdata->dev_irq, xlgmac_isr,
465 			       IRQF_SHARED, netdev->name, pdata);
466 	if (ret) {
467 		netdev_alert(netdev, "error requesting irq %d\n",
468 			     pdata->dev_irq);
469 		return ret;
470 	}
471 
472 	if (!pdata->per_channel_irq)
473 		return 0;
474 
475 	channel = pdata->channel_head;
476 	for (i = 0; i < pdata->channel_count; i++, channel++) {
477 		snprintf(channel->dma_irq_name,
478 			 sizeof(channel->dma_irq_name) - 1,
479 			 "%s-TxRx-%u", netdev_name(netdev),
480 			 channel->queue_index);
481 
482 		ret = devm_request_irq(pdata->dev, channel->dma_irq,
483 				       xlgmac_dma_isr, 0,
484 				       channel->dma_irq_name, channel);
485 		if (ret) {
486 			netdev_alert(netdev, "error requesting irq %d\n",
487 				     channel->dma_irq);
488 			goto err_irq;
489 		}
490 	}
491 
492 	return 0;
493 
494 err_irq:
495 	/* Using an unsigned int, 'i' will go to UINT_MAX and exit */
496 	for (i--, channel--; i < pdata->channel_count; i--, channel--)
497 		devm_free_irq(pdata->dev, channel->dma_irq, channel);
498 
499 	devm_free_irq(pdata->dev, pdata->dev_irq, pdata);
500 
501 	return ret;
502 }
503 
504 static void xlgmac_free_irqs(struct xlgmac_pdata *pdata)
505 {
506 	struct xlgmac_channel *channel;
507 	unsigned int i;
508 
509 	devm_free_irq(pdata->dev, pdata->dev_irq, pdata);
510 
511 	if (!pdata->per_channel_irq)
512 		return;
513 
514 	channel = pdata->channel_head;
515 	for (i = 0; i < pdata->channel_count; i++, channel++)
516 		devm_free_irq(pdata->dev, channel->dma_irq, channel);
517 }
518 
519 static void xlgmac_free_tx_data(struct xlgmac_pdata *pdata)
520 {
521 	struct xlgmac_desc_ops *desc_ops = &pdata->desc_ops;
522 	struct xlgmac_desc_data *desc_data;
523 	struct xlgmac_channel *channel;
524 	struct xlgmac_ring *ring;
525 	unsigned int i, j;
526 
527 	channel = pdata->channel_head;
528 	for (i = 0; i < pdata->channel_count; i++, channel++) {
529 		ring = channel->tx_ring;
530 		if (!ring)
531 			break;
532 
533 		for (j = 0; j < ring->dma_desc_count; j++) {
534 			desc_data = XLGMAC_GET_DESC_DATA(ring, j);
535 			desc_ops->unmap_desc_data(pdata, desc_data);
536 		}
537 	}
538 }
539 
540 static void xlgmac_free_rx_data(struct xlgmac_pdata *pdata)
541 {
542 	struct xlgmac_desc_ops *desc_ops = &pdata->desc_ops;
543 	struct xlgmac_desc_data *desc_data;
544 	struct xlgmac_channel *channel;
545 	struct xlgmac_ring *ring;
546 	unsigned int i, j;
547 
548 	channel = pdata->channel_head;
549 	for (i = 0; i < pdata->channel_count; i++, channel++) {
550 		ring = channel->rx_ring;
551 		if (!ring)
552 			break;
553 
554 		for (j = 0; j < ring->dma_desc_count; j++) {
555 			desc_data = XLGMAC_GET_DESC_DATA(ring, j);
556 			desc_ops->unmap_desc_data(pdata, desc_data);
557 		}
558 	}
559 }
560 
561 static int xlgmac_start(struct xlgmac_pdata *pdata)
562 {
563 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
564 	struct net_device *netdev = pdata->netdev;
565 	int ret;
566 
567 	hw_ops->init(pdata);
568 	xlgmac_napi_enable(pdata, 1);
569 
570 	ret = xlgmac_request_irqs(pdata);
571 	if (ret)
572 		goto err_napi;
573 
574 	hw_ops->enable_tx(pdata);
575 	hw_ops->enable_rx(pdata);
576 	netif_tx_start_all_queues(netdev);
577 
578 	return 0;
579 
580 err_napi:
581 	xlgmac_napi_disable(pdata, 1);
582 	hw_ops->exit(pdata);
583 
584 	return ret;
585 }
586 
587 static void xlgmac_stop(struct xlgmac_pdata *pdata)
588 {
589 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
590 	struct net_device *netdev = pdata->netdev;
591 	struct xlgmac_channel *channel;
592 	struct netdev_queue *txq;
593 	unsigned int i;
594 
595 	netif_tx_stop_all_queues(netdev);
596 	xlgmac_stop_timers(pdata);
597 	hw_ops->disable_tx(pdata);
598 	hw_ops->disable_rx(pdata);
599 	xlgmac_free_irqs(pdata);
600 	xlgmac_napi_disable(pdata, 1);
601 	hw_ops->exit(pdata);
602 
603 	channel = pdata->channel_head;
604 	for (i = 0; i < pdata->channel_count; i++, channel++) {
605 		if (!channel->tx_ring)
606 			continue;
607 
608 		txq = netdev_get_tx_queue(netdev, channel->queue_index);
609 		netdev_tx_reset_queue(txq);
610 	}
611 }
612 
613 static void xlgmac_restart_dev(struct xlgmac_pdata *pdata)
614 {
615 	/* If not running, "restart" will happen on open */
616 	if (!netif_running(pdata->netdev))
617 		return;
618 
619 	xlgmac_stop(pdata);
620 
621 	xlgmac_free_tx_data(pdata);
622 	xlgmac_free_rx_data(pdata);
623 
624 	xlgmac_start(pdata);
625 }
626 
627 static void xlgmac_restart(struct work_struct *work)
628 {
629 	struct xlgmac_pdata *pdata = container_of(work,
630 						   struct xlgmac_pdata,
631 						   restart_work);
632 
633 	rtnl_lock();
634 
635 	xlgmac_restart_dev(pdata);
636 
637 	rtnl_unlock();
638 }
639 
640 static int xlgmac_open(struct net_device *netdev)
641 {
642 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
643 	struct xlgmac_desc_ops *desc_ops;
644 	int ret;
645 
646 	desc_ops = &pdata->desc_ops;
647 
648 	/* TODO: Initialize the phy */
649 
650 	/* Calculate the Rx buffer size before allocating rings */
651 	ret = xlgmac_calc_rx_buf_size(netdev, netdev->mtu);
652 	if (ret < 0)
653 		return ret;
654 	pdata->rx_buf_size = ret;
655 
656 	/* Allocate the channels and rings */
657 	ret = desc_ops->alloc_channles_and_rings(pdata);
658 	if (ret)
659 		return ret;
660 
661 	INIT_WORK(&pdata->restart_work, xlgmac_restart);
662 	xlgmac_init_timers(pdata);
663 
664 	ret = xlgmac_start(pdata);
665 	if (ret)
666 		goto err_channels_and_rings;
667 
668 	return 0;
669 
670 err_channels_and_rings:
671 	desc_ops->free_channels_and_rings(pdata);
672 
673 	return ret;
674 }
675 
676 static int xlgmac_close(struct net_device *netdev)
677 {
678 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
679 	struct xlgmac_desc_ops *desc_ops;
680 
681 	desc_ops = &pdata->desc_ops;
682 
683 	/* Stop the device */
684 	xlgmac_stop(pdata);
685 
686 	/* Free the channels and rings */
687 	desc_ops->free_channels_and_rings(pdata);
688 
689 	return 0;
690 }
691 
692 static void xlgmac_tx_timeout(struct net_device *netdev, unsigned int txqueue)
693 {
694 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
695 
696 	netdev_warn(netdev, "tx timeout, device restarting\n");
697 	schedule_work(&pdata->restart_work);
698 }
699 
700 static int xlgmac_xmit(struct sk_buff *skb, struct net_device *netdev)
701 {
702 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
703 	struct xlgmac_pkt_info *tx_pkt_info;
704 	struct xlgmac_desc_ops *desc_ops;
705 	struct xlgmac_channel *channel;
706 	struct xlgmac_hw_ops *hw_ops;
707 	struct netdev_queue *txq;
708 	struct xlgmac_ring *ring;
709 	int ret;
710 
711 	desc_ops = &pdata->desc_ops;
712 	hw_ops = &pdata->hw_ops;
713 
714 	XLGMAC_PR("skb->len = %d\n", skb->len);
715 
716 	channel = pdata->channel_head + skb->queue_mapping;
717 	txq = netdev_get_tx_queue(netdev, channel->queue_index);
718 	ring = channel->tx_ring;
719 	tx_pkt_info = &ring->pkt_info;
720 
721 	if (skb->len == 0) {
722 		netif_err(pdata, tx_err, netdev,
723 			  "empty skb received from stack\n");
724 		dev_kfree_skb_any(skb);
725 		return NETDEV_TX_OK;
726 	}
727 
728 	/* Prepare preliminary packet info for TX */
729 	memset(tx_pkt_info, 0, sizeof(*tx_pkt_info));
730 	xlgmac_prep_tx_pkt(pdata, ring, skb, tx_pkt_info);
731 
732 	/* Check that there are enough descriptors available */
733 	ret = xlgmac_maybe_stop_tx_queue(channel, ring,
734 					 tx_pkt_info->desc_count);
735 	if (ret)
736 		return ret;
737 
738 	ret = xlgmac_prep_tso(skb, tx_pkt_info);
739 	if (ret) {
740 		netif_err(pdata, tx_err, netdev,
741 			  "error processing TSO packet\n");
742 		dev_kfree_skb_any(skb);
743 		return ret;
744 	}
745 	xlgmac_prep_vlan(skb, tx_pkt_info);
746 
747 	if (!desc_ops->map_tx_skb(channel, skb)) {
748 		dev_kfree_skb_any(skb);
749 		return NETDEV_TX_OK;
750 	}
751 
752 	/* Report on the actual number of bytes (to be) sent */
753 	netdev_tx_sent_queue(txq, tx_pkt_info->tx_bytes);
754 
755 	/* Configure required descriptor fields for transmission */
756 	hw_ops->dev_xmit(channel);
757 
758 	if (netif_msg_pktdata(pdata))
759 		xlgmac_print_pkt(netdev, skb, true);
760 
761 	/* Stop the queue in advance if there may not be enough descriptors */
762 	xlgmac_maybe_stop_tx_queue(channel, ring, XLGMAC_TX_MAX_DESC_NR);
763 
764 	return NETDEV_TX_OK;
765 }
766 
767 static void xlgmac_get_stats64(struct net_device *netdev,
768 			       struct rtnl_link_stats64 *s)
769 {
770 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
771 	struct xlgmac_stats *pstats = &pdata->stats;
772 
773 	pdata->hw_ops.read_mmc_stats(pdata);
774 
775 	s->rx_packets = pstats->rxframecount_gb;
776 	s->rx_bytes = pstats->rxoctetcount_gb;
777 	s->rx_errors = pstats->rxframecount_gb -
778 		       pstats->rxbroadcastframes_g -
779 		       pstats->rxmulticastframes_g -
780 		       pstats->rxunicastframes_g;
781 	s->multicast = pstats->rxmulticastframes_g;
782 	s->rx_length_errors = pstats->rxlengtherror;
783 	s->rx_crc_errors = pstats->rxcrcerror;
784 	s->rx_fifo_errors = pstats->rxfifooverflow;
785 
786 	s->tx_packets = pstats->txframecount_gb;
787 	s->tx_bytes = pstats->txoctetcount_gb;
788 	s->tx_errors = pstats->txframecount_gb - pstats->txframecount_g;
789 	s->tx_dropped = netdev->stats.tx_dropped;
790 }
791 
792 static int xlgmac_set_mac_address(struct net_device *netdev, void *addr)
793 {
794 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
795 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
796 	struct sockaddr *saddr = addr;
797 
798 	if (!is_valid_ether_addr(saddr->sa_data))
799 		return -EADDRNOTAVAIL;
800 
801 	memcpy(netdev->dev_addr, saddr->sa_data, netdev->addr_len);
802 
803 	hw_ops->set_mac_address(pdata, netdev->dev_addr);
804 
805 	return 0;
806 }
807 
808 static int xlgmac_ioctl(struct net_device *netdev,
809 			struct ifreq *ifreq, int cmd)
810 {
811 	if (!netif_running(netdev))
812 		return -ENODEV;
813 
814 	return 0;
815 }
816 
817 static int xlgmac_change_mtu(struct net_device *netdev, int mtu)
818 {
819 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
820 	int ret;
821 
822 	ret = xlgmac_calc_rx_buf_size(netdev, mtu);
823 	if (ret < 0)
824 		return ret;
825 
826 	pdata->rx_buf_size = ret;
827 	netdev->mtu = mtu;
828 
829 	xlgmac_restart_dev(pdata);
830 
831 	return 0;
832 }
833 
834 static int xlgmac_vlan_rx_add_vid(struct net_device *netdev,
835 				  __be16 proto,
836 				  u16 vid)
837 {
838 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
839 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
840 
841 	set_bit(vid, pdata->active_vlans);
842 	hw_ops->update_vlan_hash_table(pdata);
843 
844 	return 0;
845 }
846 
847 static int xlgmac_vlan_rx_kill_vid(struct net_device *netdev,
848 				   __be16 proto,
849 				   u16 vid)
850 {
851 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
852 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
853 
854 	clear_bit(vid, pdata->active_vlans);
855 	hw_ops->update_vlan_hash_table(pdata);
856 
857 	return 0;
858 }
859 
860 #ifdef CONFIG_NET_POLL_CONTROLLER
861 static void xlgmac_poll_controller(struct net_device *netdev)
862 {
863 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
864 	struct xlgmac_channel *channel;
865 	unsigned int i;
866 
867 	if (pdata->per_channel_irq) {
868 		channel = pdata->channel_head;
869 		for (i = 0; i < pdata->channel_count; i++, channel++)
870 			xlgmac_dma_isr(channel->dma_irq, channel);
871 	} else {
872 		disable_irq(pdata->dev_irq);
873 		xlgmac_isr(pdata->dev_irq, pdata);
874 		enable_irq(pdata->dev_irq);
875 	}
876 }
877 #endif /* CONFIG_NET_POLL_CONTROLLER */
878 
879 static int xlgmac_set_features(struct net_device *netdev,
880 			       netdev_features_t features)
881 {
882 	netdev_features_t rxhash, rxcsum, rxvlan, rxvlan_filter;
883 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
884 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
885 	int ret = 0;
886 
887 	rxhash = pdata->netdev_features & NETIF_F_RXHASH;
888 	rxcsum = pdata->netdev_features & NETIF_F_RXCSUM;
889 	rxvlan = pdata->netdev_features & NETIF_F_HW_VLAN_CTAG_RX;
890 	rxvlan_filter = pdata->netdev_features & NETIF_F_HW_VLAN_CTAG_FILTER;
891 
892 	if ((features & NETIF_F_RXHASH) && !rxhash)
893 		ret = hw_ops->enable_rss(pdata);
894 	else if (!(features & NETIF_F_RXHASH) && rxhash)
895 		ret = hw_ops->disable_rss(pdata);
896 	if (ret)
897 		return ret;
898 
899 	if ((features & NETIF_F_RXCSUM) && !rxcsum)
900 		hw_ops->enable_rx_csum(pdata);
901 	else if (!(features & NETIF_F_RXCSUM) && rxcsum)
902 		hw_ops->disable_rx_csum(pdata);
903 
904 	if ((features & NETIF_F_HW_VLAN_CTAG_RX) && !rxvlan)
905 		hw_ops->enable_rx_vlan_stripping(pdata);
906 	else if (!(features & NETIF_F_HW_VLAN_CTAG_RX) && rxvlan)
907 		hw_ops->disable_rx_vlan_stripping(pdata);
908 
909 	if ((features & NETIF_F_HW_VLAN_CTAG_FILTER) && !rxvlan_filter)
910 		hw_ops->enable_rx_vlan_filtering(pdata);
911 	else if (!(features & NETIF_F_HW_VLAN_CTAG_FILTER) && rxvlan_filter)
912 		hw_ops->disable_rx_vlan_filtering(pdata);
913 
914 	pdata->netdev_features = features;
915 
916 	return 0;
917 }
918 
919 static void xlgmac_set_rx_mode(struct net_device *netdev)
920 {
921 	struct xlgmac_pdata *pdata = netdev_priv(netdev);
922 	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
923 
924 	hw_ops->config_rx_mode(pdata);
925 }
926 
927 static const struct net_device_ops xlgmac_netdev_ops = {
928 	.ndo_open		= xlgmac_open,
929 	.ndo_stop		= xlgmac_close,
930 	.ndo_start_xmit		= xlgmac_xmit,
931 	.ndo_tx_timeout		= xlgmac_tx_timeout,
932 	.ndo_get_stats64	= xlgmac_get_stats64,
933 	.ndo_change_mtu		= xlgmac_change_mtu,
934 	.ndo_set_mac_address	= xlgmac_set_mac_address,
935 	.ndo_validate_addr	= eth_validate_addr,
936 	.ndo_do_ioctl		= xlgmac_ioctl,
937 	.ndo_vlan_rx_add_vid	= xlgmac_vlan_rx_add_vid,
938 	.ndo_vlan_rx_kill_vid	= xlgmac_vlan_rx_kill_vid,
939 #ifdef CONFIG_NET_POLL_CONTROLLER
940 	.ndo_poll_controller	= xlgmac_poll_controller,
941 #endif
942 	.ndo_set_features	= xlgmac_set_features,
943 	.ndo_set_rx_mode	= xlgmac_set_rx_mode,
944 };
945 
946 const struct net_device_ops *xlgmac_get_netdev_ops(void)
947 {
948 	return &xlgmac_netdev_ops;
949 }
950 
951 static void xlgmac_rx_refresh(struct xlgmac_channel *channel)
952 {
953 	struct xlgmac_pdata *pdata = channel->pdata;
954 	struct xlgmac_ring *ring = channel->rx_ring;
955 	struct xlgmac_desc_data *desc_data;
956 	struct xlgmac_desc_ops *desc_ops;
957 	struct xlgmac_hw_ops *hw_ops;
958 
959 	desc_ops = &pdata->desc_ops;
960 	hw_ops = &pdata->hw_ops;
961 
962 	while (ring->dirty != ring->cur) {
963 		desc_data = XLGMAC_GET_DESC_DATA(ring, ring->dirty);
964 
965 		/* Reset desc_data values */
966 		desc_ops->unmap_desc_data(pdata, desc_data);
967 
968 		if (desc_ops->map_rx_buffer(pdata, ring, desc_data))
969 			break;
970 
971 		hw_ops->rx_desc_reset(pdata, desc_data, ring->dirty);
972 
973 		ring->dirty++;
974 	}
975 
976 	/* Make sure everything is written before the register write */
977 	wmb();
978 
979 	/* Update the Rx Tail Pointer Register with address of
980 	 * the last cleaned entry
981 	 */
982 	desc_data = XLGMAC_GET_DESC_DATA(ring, ring->dirty - 1);
983 	writel(lower_32_bits(desc_data->dma_desc_addr),
984 	       XLGMAC_DMA_REG(channel, DMA_CH_RDTR_LO));
985 }
986 
987 static struct sk_buff *xlgmac_create_skb(struct xlgmac_pdata *pdata,
988 					 struct napi_struct *napi,
989 					 struct xlgmac_desc_data *desc_data,
990 					 unsigned int len)
991 {
992 	unsigned int copy_len;
993 	struct sk_buff *skb;
994 	u8 *packet;
995 
996 	skb = napi_alloc_skb(napi, desc_data->rx.hdr.dma_len);
997 	if (!skb)
998 		return NULL;
999 
1000 	/* Start with the header buffer which may contain just the header
1001 	 * or the header plus data
1002 	 */
1003 	dma_sync_single_range_for_cpu(pdata->dev, desc_data->rx.hdr.dma_base,
1004 				      desc_data->rx.hdr.dma_off,
1005 				      desc_data->rx.hdr.dma_len,
1006 				      DMA_FROM_DEVICE);
1007 
1008 	packet = page_address(desc_data->rx.hdr.pa.pages) +
1009 		 desc_data->rx.hdr.pa.pages_offset;
1010 	copy_len = (desc_data->rx.hdr_len) ? desc_data->rx.hdr_len : len;
1011 	copy_len = min(desc_data->rx.hdr.dma_len, copy_len);
1012 	skb_copy_to_linear_data(skb, packet, copy_len);
1013 	skb_put(skb, copy_len);
1014 
1015 	len -= copy_len;
1016 	if (len) {
1017 		/* Add the remaining data as a frag */
1018 		dma_sync_single_range_for_cpu(pdata->dev,
1019 					      desc_data->rx.buf.dma_base,
1020 					      desc_data->rx.buf.dma_off,
1021 					      desc_data->rx.buf.dma_len,
1022 					      DMA_FROM_DEVICE);
1023 
1024 		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
1025 				desc_data->rx.buf.pa.pages,
1026 				desc_data->rx.buf.pa.pages_offset,
1027 				len, desc_data->rx.buf.dma_len);
1028 		desc_data->rx.buf.pa.pages = NULL;
1029 	}
1030 
1031 	return skb;
1032 }
1033 
1034 static int xlgmac_tx_poll(struct xlgmac_channel *channel)
1035 {
1036 	struct xlgmac_pdata *pdata = channel->pdata;
1037 	struct xlgmac_ring *ring = channel->tx_ring;
1038 	struct net_device *netdev = pdata->netdev;
1039 	unsigned int tx_packets = 0, tx_bytes = 0;
1040 	struct xlgmac_desc_data *desc_data;
1041 	struct xlgmac_dma_desc *dma_desc;
1042 	struct xlgmac_desc_ops *desc_ops;
1043 	struct xlgmac_hw_ops *hw_ops;
1044 	struct netdev_queue *txq;
1045 	int processed = 0;
1046 	unsigned int cur;
1047 
1048 	desc_ops = &pdata->desc_ops;
1049 	hw_ops = &pdata->hw_ops;
1050 
1051 	/* Nothing to do if there isn't a Tx ring for this channel */
1052 	if (!ring)
1053 		return 0;
1054 
1055 	cur = ring->cur;
1056 
1057 	/* Be sure we get ring->cur before accessing descriptor data */
1058 	smp_rmb();
1059 
1060 	txq = netdev_get_tx_queue(netdev, channel->queue_index);
1061 
1062 	while ((processed < XLGMAC_TX_DESC_MAX_PROC) &&
1063 	       (ring->dirty != cur)) {
1064 		desc_data = XLGMAC_GET_DESC_DATA(ring, ring->dirty);
1065 		dma_desc = desc_data->dma_desc;
1066 
1067 		if (!hw_ops->tx_complete(dma_desc))
1068 			break;
1069 
1070 		/* Make sure descriptor fields are read after reading
1071 		 * the OWN bit
1072 		 */
1073 		dma_rmb();
1074 
1075 		if (netif_msg_tx_done(pdata))
1076 			xlgmac_dump_tx_desc(pdata, ring, ring->dirty, 1, 0);
1077 
1078 		if (hw_ops->is_last_desc(dma_desc)) {
1079 			tx_packets += desc_data->tx.packets;
1080 			tx_bytes += desc_data->tx.bytes;
1081 		}
1082 
1083 		/* Free the SKB and reset the descriptor for re-use */
1084 		desc_ops->unmap_desc_data(pdata, desc_data);
1085 		hw_ops->tx_desc_reset(desc_data);
1086 
1087 		processed++;
1088 		ring->dirty++;
1089 	}
1090 
1091 	if (!processed)
1092 		return 0;
1093 
1094 	netdev_tx_completed_queue(txq, tx_packets, tx_bytes);
1095 
1096 	if ((ring->tx.queue_stopped == 1) &&
1097 	    (xlgmac_tx_avail_desc(ring) > XLGMAC_TX_DESC_MIN_FREE)) {
1098 		ring->tx.queue_stopped = 0;
1099 		netif_tx_wake_queue(txq);
1100 	}
1101 
1102 	XLGMAC_PR("processed=%d\n", processed);
1103 
1104 	return processed;
1105 }
1106 
1107 static int xlgmac_rx_poll(struct xlgmac_channel *channel, int budget)
1108 {
1109 	struct xlgmac_pdata *pdata = channel->pdata;
1110 	struct xlgmac_ring *ring = channel->rx_ring;
1111 	struct net_device *netdev = pdata->netdev;
1112 	unsigned int len, dma_desc_len, max_len;
1113 	unsigned int context_next, context;
1114 	struct xlgmac_desc_data *desc_data;
1115 	struct xlgmac_pkt_info *pkt_info;
1116 	unsigned int incomplete, error;
1117 	struct xlgmac_hw_ops *hw_ops;
1118 	unsigned int received = 0;
1119 	struct napi_struct *napi;
1120 	struct sk_buff *skb;
1121 	int packet_count = 0;
1122 
1123 	hw_ops = &pdata->hw_ops;
1124 
1125 	/* Nothing to do if there isn't a Rx ring for this channel */
1126 	if (!ring)
1127 		return 0;
1128 
1129 	incomplete = 0;
1130 	context_next = 0;
1131 
1132 	napi = (pdata->per_channel_irq) ? &channel->napi : &pdata->napi;
1133 
1134 	desc_data = XLGMAC_GET_DESC_DATA(ring, ring->cur);
1135 	pkt_info = &ring->pkt_info;
1136 	while (packet_count < budget) {
1137 		/* First time in loop see if we need to restore state */
1138 		if (!received && desc_data->state_saved) {
1139 			skb = desc_data->state.skb;
1140 			error = desc_data->state.error;
1141 			len = desc_data->state.len;
1142 		} else {
1143 			memset(pkt_info, 0, sizeof(*pkt_info));
1144 			skb = NULL;
1145 			error = 0;
1146 			len = 0;
1147 		}
1148 
1149 read_again:
1150 		desc_data = XLGMAC_GET_DESC_DATA(ring, ring->cur);
1151 
1152 		if (xlgmac_rx_dirty_desc(ring) > XLGMAC_RX_DESC_MAX_DIRTY)
1153 			xlgmac_rx_refresh(channel);
1154 
1155 		if (hw_ops->dev_read(channel))
1156 			break;
1157 
1158 		received++;
1159 		ring->cur++;
1160 
1161 		incomplete = XLGMAC_GET_REG_BITS(
1162 					pkt_info->attributes,
1163 					RX_PACKET_ATTRIBUTES_INCOMPLETE_POS,
1164 					RX_PACKET_ATTRIBUTES_INCOMPLETE_LEN);
1165 		context_next = XLGMAC_GET_REG_BITS(
1166 					pkt_info->attributes,
1167 					RX_PACKET_ATTRIBUTES_CONTEXT_NEXT_POS,
1168 					RX_PACKET_ATTRIBUTES_CONTEXT_NEXT_LEN);
1169 		context = XLGMAC_GET_REG_BITS(
1170 					pkt_info->attributes,
1171 					RX_PACKET_ATTRIBUTES_CONTEXT_POS,
1172 					RX_PACKET_ATTRIBUTES_CONTEXT_LEN);
1173 
1174 		/* Earlier error, just drain the remaining data */
1175 		if ((incomplete || context_next) && error)
1176 			goto read_again;
1177 
1178 		if (error || pkt_info->errors) {
1179 			if (pkt_info->errors)
1180 				netif_err(pdata, rx_err, netdev,
1181 					  "error in received packet\n");
1182 			dev_kfree_skb(skb);
1183 			goto next_packet;
1184 		}
1185 
1186 		if (!context) {
1187 			/* Length is cumulative, get this descriptor's length */
1188 			dma_desc_len = desc_data->rx.len - len;
1189 			len += dma_desc_len;
1190 
1191 			if (dma_desc_len && !skb) {
1192 				skb = xlgmac_create_skb(pdata, napi, desc_data,
1193 							dma_desc_len);
1194 				if (!skb)
1195 					error = 1;
1196 			} else if (dma_desc_len) {
1197 				dma_sync_single_range_for_cpu(
1198 						pdata->dev,
1199 						desc_data->rx.buf.dma_base,
1200 						desc_data->rx.buf.dma_off,
1201 						desc_data->rx.buf.dma_len,
1202 						DMA_FROM_DEVICE);
1203 
1204 				skb_add_rx_frag(
1205 					skb, skb_shinfo(skb)->nr_frags,
1206 					desc_data->rx.buf.pa.pages,
1207 					desc_data->rx.buf.pa.pages_offset,
1208 					dma_desc_len,
1209 					desc_data->rx.buf.dma_len);
1210 				desc_data->rx.buf.pa.pages = NULL;
1211 			}
1212 		}
1213 
1214 		if (incomplete || context_next)
1215 			goto read_again;
1216 
1217 		if (!skb)
1218 			goto next_packet;
1219 
1220 		/* Be sure we don't exceed the configured MTU */
1221 		max_len = netdev->mtu + ETH_HLEN;
1222 		if (!(netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
1223 		    (skb->protocol == htons(ETH_P_8021Q)))
1224 			max_len += VLAN_HLEN;
1225 
1226 		if (skb->len > max_len) {
1227 			netif_err(pdata, rx_err, netdev,
1228 				  "packet length exceeds configured MTU\n");
1229 			dev_kfree_skb(skb);
1230 			goto next_packet;
1231 		}
1232 
1233 		if (netif_msg_pktdata(pdata))
1234 			xlgmac_print_pkt(netdev, skb, false);
1235 
1236 		skb_checksum_none_assert(skb);
1237 		if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
1238 					RX_PACKET_ATTRIBUTES_CSUM_DONE_POS,
1239 				    RX_PACKET_ATTRIBUTES_CSUM_DONE_LEN))
1240 			skb->ip_summed = CHECKSUM_UNNECESSARY;
1241 
1242 		if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
1243 					RX_PACKET_ATTRIBUTES_VLAN_CTAG_POS,
1244 				    RX_PACKET_ATTRIBUTES_VLAN_CTAG_LEN)) {
1245 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
1246 					       pkt_info->vlan_ctag);
1247 			pdata->stats.rx_vlan_packets++;
1248 		}
1249 
1250 		if (XLGMAC_GET_REG_BITS(pkt_info->attributes,
1251 					RX_PACKET_ATTRIBUTES_RSS_HASH_POS,
1252 				    RX_PACKET_ATTRIBUTES_RSS_HASH_LEN))
1253 			skb_set_hash(skb, pkt_info->rss_hash,
1254 				     pkt_info->rss_hash_type);
1255 
1256 		skb->dev = netdev;
1257 		skb->protocol = eth_type_trans(skb, netdev);
1258 		skb_record_rx_queue(skb, channel->queue_index);
1259 
1260 		napi_gro_receive(napi, skb);
1261 
1262 next_packet:
1263 		packet_count++;
1264 	}
1265 
1266 	/* Check if we need to save state before leaving */
1267 	if (received && (incomplete || context_next)) {
1268 		desc_data = XLGMAC_GET_DESC_DATA(ring, ring->cur);
1269 		desc_data->state_saved = 1;
1270 		desc_data->state.skb = skb;
1271 		desc_data->state.len = len;
1272 		desc_data->state.error = error;
1273 	}
1274 
1275 	XLGMAC_PR("packet_count = %d\n", packet_count);
1276 
1277 	return packet_count;
1278 }
1279 
1280 static int xlgmac_one_poll(struct napi_struct *napi, int budget)
1281 {
1282 	struct xlgmac_channel *channel = container_of(napi,
1283 						struct xlgmac_channel,
1284 						napi);
1285 	int processed = 0;
1286 
1287 	XLGMAC_PR("budget=%d\n", budget);
1288 
1289 	/* Cleanup Tx ring first */
1290 	xlgmac_tx_poll(channel);
1291 
1292 	/* Process Rx ring next */
1293 	processed = xlgmac_rx_poll(channel, budget);
1294 
1295 	/* If we processed everything, we are done */
1296 	if (processed < budget) {
1297 		/* Turn off polling */
1298 		napi_complete_done(napi, processed);
1299 
1300 		/* Enable Tx and Rx interrupts */
1301 		enable_irq(channel->dma_irq);
1302 	}
1303 
1304 	XLGMAC_PR("received = %d\n", processed);
1305 
1306 	return processed;
1307 }
1308 
1309 static int xlgmac_all_poll(struct napi_struct *napi, int budget)
1310 {
1311 	struct xlgmac_pdata *pdata = container_of(napi,
1312 						   struct xlgmac_pdata,
1313 						   napi);
1314 	struct xlgmac_channel *channel;
1315 	int processed, last_processed;
1316 	int ring_budget;
1317 	unsigned int i;
1318 
1319 	XLGMAC_PR("budget=%d\n", budget);
1320 
1321 	processed = 0;
1322 	ring_budget = budget / pdata->rx_ring_count;
1323 	do {
1324 		last_processed = processed;
1325 
1326 		channel = pdata->channel_head;
1327 		for (i = 0; i < pdata->channel_count; i++, channel++) {
1328 			/* Cleanup Tx ring first */
1329 			xlgmac_tx_poll(channel);
1330 
1331 			/* Process Rx ring next */
1332 			if (ring_budget > (budget - processed))
1333 				ring_budget = budget - processed;
1334 			processed += xlgmac_rx_poll(channel, ring_budget);
1335 		}
1336 	} while ((processed < budget) && (processed != last_processed));
1337 
1338 	/* If we processed everything, we are done */
1339 	if (processed < budget) {
1340 		/* Turn off polling */
1341 		napi_complete_done(napi, processed);
1342 
1343 		/* Enable Tx and Rx interrupts */
1344 		xlgmac_enable_rx_tx_ints(pdata);
1345 	}
1346 
1347 	XLGMAC_PR("received = %d\n", processed);
1348 
1349 	return processed;
1350 }
1351