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 "dwc-xlgmac.h"
19#include "dwc-xlgmac-reg.h"
20
21static void xlgmac_unmap_desc_data(struct xlgmac_pdata *pdata,
22				   struct xlgmac_desc_data *desc_data)
23{
24	if (desc_data->skb_dma) {
25		if (desc_data->mapped_as_page) {
26			dma_unmap_page(pdata->dev, desc_data->skb_dma,
27				       desc_data->skb_dma_len, DMA_TO_DEVICE);
28		} else {
29			dma_unmap_single(pdata->dev, desc_data->skb_dma,
30					 desc_data->skb_dma_len, DMA_TO_DEVICE);
31		}
32		desc_data->skb_dma = 0;
33		desc_data->skb_dma_len = 0;
34	}
35
36	if (desc_data->skb) {
37		dev_kfree_skb_any(desc_data->skb);
38		desc_data->skb = NULL;
39	}
40
41	if (desc_data->rx.hdr.pa.pages)
42		put_page(desc_data->rx.hdr.pa.pages);
43
44	if (desc_data->rx.hdr.pa_unmap.pages) {
45		dma_unmap_page(pdata->dev, desc_data->rx.hdr.pa_unmap.pages_dma,
46			       desc_data->rx.hdr.pa_unmap.pages_len,
47			       DMA_FROM_DEVICE);
48		put_page(desc_data->rx.hdr.pa_unmap.pages);
49	}
50
51	if (desc_data->rx.buf.pa.pages)
52		put_page(desc_data->rx.buf.pa.pages);
53
54	if (desc_data->rx.buf.pa_unmap.pages) {
55		dma_unmap_page(pdata->dev, desc_data->rx.buf.pa_unmap.pages_dma,
56			       desc_data->rx.buf.pa_unmap.pages_len,
57			       DMA_FROM_DEVICE);
58		put_page(desc_data->rx.buf.pa_unmap.pages);
59	}
60
61	memset(&desc_data->tx, 0, sizeof(desc_data->tx));
62	memset(&desc_data->rx, 0, sizeof(desc_data->rx));
63
64	desc_data->mapped_as_page = 0;
65
66	if (desc_data->state_saved) {
67		desc_data->state_saved = 0;
68		desc_data->state.skb = NULL;
69		desc_data->state.len = 0;
70		desc_data->state.error = 0;
71	}
72}
73
74static void xlgmac_free_ring(struct xlgmac_pdata *pdata,
75			     struct xlgmac_ring *ring)
76{
77	struct xlgmac_desc_data *desc_data;
78	unsigned int i;
79
80	if (!ring)
81		return;
82
83	if (ring->desc_data_head) {
84		for (i = 0; i < ring->dma_desc_count; i++) {
85			desc_data = XLGMAC_GET_DESC_DATA(ring, i);
86			xlgmac_unmap_desc_data(pdata, desc_data);
87		}
88
89		kfree(ring->desc_data_head);
90		ring->desc_data_head = NULL;
91	}
92
93	if (ring->rx_hdr_pa.pages) {
94		dma_unmap_page(pdata->dev, ring->rx_hdr_pa.pages_dma,
95			       ring->rx_hdr_pa.pages_len, DMA_FROM_DEVICE);
96		put_page(ring->rx_hdr_pa.pages);
97
98		ring->rx_hdr_pa.pages = NULL;
99		ring->rx_hdr_pa.pages_len = 0;
100		ring->rx_hdr_pa.pages_offset = 0;
101		ring->rx_hdr_pa.pages_dma = 0;
102	}
103
104	if (ring->rx_buf_pa.pages) {
105		dma_unmap_page(pdata->dev, ring->rx_buf_pa.pages_dma,
106			       ring->rx_buf_pa.pages_len, DMA_FROM_DEVICE);
107		put_page(ring->rx_buf_pa.pages);
108
109		ring->rx_buf_pa.pages = NULL;
110		ring->rx_buf_pa.pages_len = 0;
111		ring->rx_buf_pa.pages_offset = 0;
112		ring->rx_buf_pa.pages_dma = 0;
113	}
114
115	if (ring->dma_desc_head) {
116		dma_free_coherent(pdata->dev,
117				  (sizeof(struct xlgmac_dma_desc) *
118				  ring->dma_desc_count),
119				  ring->dma_desc_head,
120				  ring->dma_desc_head_addr);
121		ring->dma_desc_head = NULL;
122	}
123}
124
125static int xlgmac_init_ring(struct xlgmac_pdata *pdata,
126			    struct xlgmac_ring *ring,
127			    unsigned int dma_desc_count)
128{
129	if (!ring)
130		return 0;
131
132	/* Descriptors */
133	ring->dma_desc_count = dma_desc_count;
134	ring->dma_desc_head = dma_alloc_coherent(pdata->dev,
135					(sizeof(struct xlgmac_dma_desc) *
136					 dma_desc_count),
137					&ring->dma_desc_head_addr,
138					GFP_KERNEL);
139	if (!ring->dma_desc_head)
140		return -ENOMEM;
141
142	/* Array of descriptor data */
143	ring->desc_data_head = kcalloc(dma_desc_count,
144					sizeof(struct xlgmac_desc_data),
145					GFP_KERNEL);
146	if (!ring->desc_data_head)
147		return -ENOMEM;
148
149	netif_dbg(pdata, drv, pdata->netdev,
150		  "dma_desc_head=%p, dma_desc_head_addr=%pad, desc_data_head=%p\n",
151		ring->dma_desc_head,
152		&ring->dma_desc_head_addr,
153		ring->desc_data_head);
154
155	return 0;
156}
157
158static void xlgmac_free_rings(struct xlgmac_pdata *pdata)
159{
160	struct xlgmac_channel *channel;
161	unsigned int i;
162
163	if (!pdata->channel_head)
164		return;
165
166	channel = pdata->channel_head;
167	for (i = 0; i < pdata->channel_count; i++, channel++) {
168		xlgmac_free_ring(pdata, channel->tx_ring);
169		xlgmac_free_ring(pdata, channel->rx_ring);
170	}
171}
172
173static int xlgmac_alloc_rings(struct xlgmac_pdata *pdata)
174{
175	struct xlgmac_channel *channel;
176	unsigned int i;
177	int ret;
178
179	channel = pdata->channel_head;
180	for (i = 0; i < pdata->channel_count; i++, channel++) {
181		netif_dbg(pdata, drv, pdata->netdev, "%s - Tx ring:\n",
182			  channel->name);
183
184		ret = xlgmac_init_ring(pdata, channel->tx_ring,
185				       pdata->tx_desc_count);
186
187		if (ret) {
188			netdev_alert(pdata->netdev,
189				     "error initializing Tx ring");
190			goto err_init_ring;
191		}
192
193		netif_dbg(pdata, drv, pdata->netdev, "%s - Rx ring:\n",
194			  channel->name);
195
196		ret = xlgmac_init_ring(pdata, channel->rx_ring,
197				       pdata->rx_desc_count);
198		if (ret) {
199			netdev_alert(pdata->netdev,
200				     "error initializing Rx ring\n");
201			goto err_init_ring;
202		}
203	}
204
205	return 0;
206
207err_init_ring:
208	xlgmac_free_rings(pdata);
209
210	return ret;
211}
212
213static void xlgmac_free_channels(struct xlgmac_pdata *pdata)
214{
215	if (!pdata->channel_head)
216		return;
217
218	kfree(pdata->channel_head->tx_ring);
219	pdata->channel_head->tx_ring = NULL;
220
221	kfree(pdata->channel_head->rx_ring);
222	pdata->channel_head->rx_ring = NULL;
223
224	kfree(pdata->channel_head);
225
226	pdata->channel_head = NULL;
227	pdata->channel_count = 0;
228}
229
230static int xlgmac_alloc_channels(struct xlgmac_pdata *pdata)
231{
232	struct xlgmac_channel *channel_head, *channel;
233	struct xlgmac_ring *tx_ring, *rx_ring;
234	int ret = -ENOMEM;
235	unsigned int i;
236
237	channel_head = kcalloc(pdata->channel_count,
238			       sizeof(struct xlgmac_channel), GFP_KERNEL);
239	if (!channel_head)
240		return ret;
241
242	netif_dbg(pdata, drv, pdata->netdev,
243		  "channel_head=%p\n", channel_head);
244
245	tx_ring = kcalloc(pdata->tx_ring_count, sizeof(struct xlgmac_ring),
246			  GFP_KERNEL);
247	if (!tx_ring)
248		goto err_tx_ring;
249
250	rx_ring = kcalloc(pdata->rx_ring_count, sizeof(struct xlgmac_ring),
251			  GFP_KERNEL);
252	if (!rx_ring)
253		goto err_rx_ring;
254
255	for (i = 0, channel = channel_head; i < pdata->channel_count;
256		i++, channel++) {
257		snprintf(channel->name, sizeof(channel->name), "channel-%u", i);
258		channel->pdata = pdata;
259		channel->queue_index = i;
260		channel->dma_regs = pdata->mac_regs + DMA_CH_BASE +
261				    (DMA_CH_INC * i);
262
263		if (pdata->per_channel_irq) {
264			/* Get the per DMA interrupt */
265			ret = pdata->channel_irq[i];
266			if (ret < 0) {
267				netdev_err(pdata->netdev,
268					   "get_irq %u failed\n",
269					   i + 1);
270				goto err_irq;
271			}
272			channel->dma_irq = ret;
273		}
274
275		if (i < pdata->tx_ring_count)
276			channel->tx_ring = tx_ring++;
277
278		if (i < pdata->rx_ring_count)
279			channel->rx_ring = rx_ring++;
280
281		netif_dbg(pdata, drv, pdata->netdev,
282			  "%s: dma_regs=%p, tx_ring=%p, rx_ring=%p\n",
283			  channel->name, channel->dma_regs,
284			  channel->tx_ring, channel->rx_ring);
285	}
286
287	pdata->channel_head = channel_head;
288
289	return 0;
290
291err_irq:
292	kfree(rx_ring);
293
294err_rx_ring:
295	kfree(tx_ring);
296
297err_tx_ring:
298	kfree(channel_head);
299
300	return ret;
301}
302
303static void xlgmac_free_channels_and_rings(struct xlgmac_pdata *pdata)
304{
305	xlgmac_free_rings(pdata);
306
307	xlgmac_free_channels(pdata);
308}
309
310static int xlgmac_alloc_channels_and_rings(struct xlgmac_pdata *pdata)
311{
312	int ret;
313
314	ret = xlgmac_alloc_channels(pdata);
315	if (ret)
316		goto err_alloc;
317
318	ret = xlgmac_alloc_rings(pdata);
319	if (ret)
320		goto err_alloc;
321
322	return 0;
323
324err_alloc:
325	xlgmac_free_channels_and_rings(pdata);
326
327	return ret;
328}
329
330static int xlgmac_alloc_pages(struct xlgmac_pdata *pdata,
331			      struct xlgmac_page_alloc *pa,
332			      gfp_t gfp, int order)
333{
334	struct page *pages = NULL;
335	dma_addr_t pages_dma;
336
337	/* Try to obtain pages, decreasing order if necessary */
338	gfp |= __GFP_COMP | __GFP_NOWARN;
339	while (order >= 0) {
340		pages = alloc_pages(gfp, order);
341		if (pages)
342			break;
343
344		order--;
345	}
346	if (!pages)
347		return -ENOMEM;
348
349	/* Map the pages */
350	pages_dma = dma_map_page(pdata->dev, pages, 0,
351				 PAGE_SIZE << order, DMA_FROM_DEVICE);
352	if (dma_mapping_error(pdata->dev, pages_dma)) {
353		put_page(pages);
354		return -ENOMEM;
355	}
356
357	pa->pages = pages;
358	pa->pages_len = PAGE_SIZE << order;
359	pa->pages_offset = 0;
360	pa->pages_dma = pages_dma;
361
362	return 0;
363}
364
365static void xlgmac_set_buffer_data(struct xlgmac_buffer_data *bd,
366				   struct xlgmac_page_alloc *pa,
367				   unsigned int len)
368{
369	get_page(pa->pages);
370	bd->pa = *pa;
371
372	bd->dma_base = pa->pages_dma;
373	bd->dma_off = pa->pages_offset;
374	bd->dma_len = len;
375
376	pa->pages_offset += len;
377	if ((pa->pages_offset + len) > pa->pages_len) {
378		/* This data descriptor is responsible for unmapping page(s) */
379		bd->pa_unmap = *pa;
380
381		/* Get a new allocation next time */
382		pa->pages = NULL;
383		pa->pages_len = 0;
384		pa->pages_offset = 0;
385		pa->pages_dma = 0;
386	}
387}
388
389static int xlgmac_map_rx_buffer(struct xlgmac_pdata *pdata,
390				struct xlgmac_ring *ring,
391				struct xlgmac_desc_data *desc_data)
392{
393	int order, ret;
394
395	if (!ring->rx_hdr_pa.pages) {
396		ret = xlgmac_alloc_pages(pdata, &ring->rx_hdr_pa,
397					 GFP_ATOMIC, 0);
398		if (ret)
399			return ret;
400	}
401
402	if (!ring->rx_buf_pa.pages) {
403		order = max_t(int, PAGE_ALLOC_COSTLY_ORDER - 1, 0);
404		ret = xlgmac_alloc_pages(pdata, &ring->rx_buf_pa,
405					 GFP_ATOMIC, order);
406		if (ret)
407			return ret;
408	}
409
410	/* Set up the header page info */
411	xlgmac_set_buffer_data(&desc_data->rx.hdr, &ring->rx_hdr_pa,
412			       XLGMAC_SKB_ALLOC_SIZE);
413
414	/* Set up the buffer page info */
415	xlgmac_set_buffer_data(&desc_data->rx.buf, &ring->rx_buf_pa,
416			       pdata->rx_buf_size);
417
418	return 0;
419}
420
421static void xlgmac_tx_desc_init(struct xlgmac_pdata *pdata)
422{
423	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
424	struct xlgmac_desc_data *desc_data;
425	struct xlgmac_dma_desc *dma_desc;
426	struct xlgmac_channel *channel;
427	struct xlgmac_ring *ring;
428	dma_addr_t dma_desc_addr;
429	unsigned int i, j;
430
431	channel = pdata->channel_head;
432	for (i = 0; i < pdata->channel_count; i++, channel++) {
433		ring = channel->tx_ring;
434		if (!ring)
435			break;
436
437		dma_desc = ring->dma_desc_head;
438		dma_desc_addr = ring->dma_desc_head_addr;
439
440		for (j = 0; j < ring->dma_desc_count; j++) {
441			desc_data = XLGMAC_GET_DESC_DATA(ring, j);
442
443			desc_data->dma_desc = dma_desc;
444			desc_data->dma_desc_addr = dma_desc_addr;
445
446			dma_desc++;
447			dma_desc_addr += sizeof(struct xlgmac_dma_desc);
448		}
449
450		ring->cur = 0;
451		ring->dirty = 0;
452		memset(&ring->tx, 0, sizeof(ring->tx));
453
454		hw_ops->tx_desc_init(channel);
455	}
456}
457
458static void xlgmac_rx_desc_init(struct xlgmac_pdata *pdata)
459{
460	struct xlgmac_hw_ops *hw_ops = &pdata->hw_ops;
461	struct xlgmac_desc_data *desc_data;
462	struct xlgmac_dma_desc *dma_desc;
463	struct xlgmac_channel *channel;
464	struct xlgmac_ring *ring;
465	dma_addr_t dma_desc_addr;
466	unsigned int i, j;
467
468	channel = pdata->channel_head;
469	for (i = 0; i < pdata->channel_count; i++, channel++) {
470		ring = channel->rx_ring;
471		if (!ring)
472			break;
473
474		dma_desc = ring->dma_desc_head;
475		dma_desc_addr = ring->dma_desc_head_addr;
476
477		for (j = 0; j < ring->dma_desc_count; j++) {
478			desc_data = XLGMAC_GET_DESC_DATA(ring, j);
479
480			desc_data->dma_desc = dma_desc;
481			desc_data->dma_desc_addr = dma_desc_addr;
482
483			if (xlgmac_map_rx_buffer(pdata, ring, desc_data))
484				break;
485
486			dma_desc++;
487			dma_desc_addr += sizeof(struct xlgmac_dma_desc);
488		}
489
490		ring->cur = 0;
491		ring->dirty = 0;
492
493		hw_ops->rx_desc_init(channel);
494	}
495}
496
497static int xlgmac_map_tx_skb(struct xlgmac_channel *channel,
498			     struct sk_buff *skb)
499{
500	struct xlgmac_pdata *pdata = channel->pdata;
501	struct xlgmac_ring *ring = channel->tx_ring;
502	unsigned int start_index, cur_index;
503	struct xlgmac_desc_data *desc_data;
504	unsigned int offset, datalen, len;
505	struct xlgmac_pkt_info *pkt_info;
506	skb_frag_t *frag;
507	unsigned int tso, vlan;
508	dma_addr_t skb_dma;
509	unsigned int i;
510
511	offset = 0;
512	start_index = ring->cur;
513	cur_index = ring->cur;
514
515	pkt_info = &ring->pkt_info;
516	pkt_info->desc_count = 0;
517	pkt_info->length = 0;
518
519	tso = XLGMAC_GET_REG_BITS(pkt_info->attributes,
520				  TX_PACKET_ATTRIBUTES_TSO_ENABLE_POS,
521				  TX_PACKET_ATTRIBUTES_TSO_ENABLE_LEN);
522	vlan = XLGMAC_GET_REG_BITS(pkt_info->attributes,
523				   TX_PACKET_ATTRIBUTES_VLAN_CTAG_POS,
524				   TX_PACKET_ATTRIBUTES_VLAN_CTAG_LEN);
525
526	/* Save space for a context descriptor if needed */
527	if ((tso && (pkt_info->mss != ring->tx.cur_mss)) ||
528	    (vlan && (pkt_info->vlan_ctag != ring->tx.cur_vlan_ctag)))
529		cur_index++;
530	desc_data = XLGMAC_GET_DESC_DATA(ring, cur_index);
531
532	if (tso) {
533		/* Map the TSO header */
534		skb_dma = dma_map_single(pdata->dev, skb->data,
535					 pkt_info->header_len, DMA_TO_DEVICE);
536		if (dma_mapping_error(pdata->dev, skb_dma)) {
537			netdev_alert(pdata->netdev, "dma_map_single failed\n");
538			goto err_out;
539		}
540		desc_data->skb_dma = skb_dma;
541		desc_data->skb_dma_len = pkt_info->header_len;
542		netif_dbg(pdata, tx_queued, pdata->netdev,
543			  "skb header: index=%u, dma=%pad, len=%u\n",
544			  cur_index, &skb_dma, pkt_info->header_len);
545
546		offset = pkt_info->header_len;
547
548		pkt_info->length += pkt_info->header_len;
549
550		cur_index++;
551		desc_data = XLGMAC_GET_DESC_DATA(ring, cur_index);
552	}
553
554	/* Map the (remainder of the) packet */
555	for (datalen = skb_headlen(skb) - offset; datalen; ) {
556		len = min_t(unsigned int, datalen, XLGMAC_TX_MAX_BUF_SIZE);
557
558		skb_dma = dma_map_single(pdata->dev, skb->data + offset, len,
559					 DMA_TO_DEVICE);
560		if (dma_mapping_error(pdata->dev, skb_dma)) {
561			netdev_alert(pdata->netdev, "dma_map_single failed\n");
562			goto err_out;
563		}
564		desc_data->skb_dma = skb_dma;
565		desc_data->skb_dma_len = len;
566		netif_dbg(pdata, tx_queued, pdata->netdev,
567			  "skb data: index=%u, dma=%pad, len=%u\n",
568			  cur_index, &skb_dma, len);
569
570		datalen -= len;
571		offset += len;
572
573		pkt_info->length += len;
574
575		cur_index++;
576		desc_data = XLGMAC_GET_DESC_DATA(ring, cur_index);
577	}
578
579	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
580		netif_dbg(pdata, tx_queued, pdata->netdev,
581			  "mapping frag %u\n", i);
582
583		frag = &skb_shinfo(skb)->frags[i];
584		offset = 0;
585
586		for (datalen = skb_frag_size(frag); datalen; ) {
587			len = min_t(unsigned int, datalen,
588				    XLGMAC_TX_MAX_BUF_SIZE);
589
590			skb_dma = skb_frag_dma_map(pdata->dev, frag, offset,
591						   len, DMA_TO_DEVICE);
592			if (dma_mapping_error(pdata->dev, skb_dma)) {
593				netdev_alert(pdata->netdev,
594					     "skb_frag_dma_map failed\n");
595				goto err_out;
596			}
597			desc_data->skb_dma = skb_dma;
598			desc_data->skb_dma_len = len;
599			desc_data->mapped_as_page = 1;
600			netif_dbg(pdata, tx_queued, pdata->netdev,
601				  "skb frag: index=%u, dma=%pad, len=%u\n",
602				  cur_index, &skb_dma, len);
603
604			datalen -= len;
605			offset += len;
606
607			pkt_info->length += len;
608
609			cur_index++;
610			desc_data = XLGMAC_GET_DESC_DATA(ring, cur_index);
611		}
612	}
613
614	/* Save the skb address in the last entry. We always have some data
615	 * that has been mapped so desc_data is always advanced past the last
616	 * piece of mapped data - use the entry pointed to by cur_index - 1.
617	 */
618	desc_data = XLGMAC_GET_DESC_DATA(ring, cur_index - 1);
619	desc_data->skb = skb;
620
621	/* Save the number of descriptor entries used */
622	pkt_info->desc_count = cur_index - start_index;
623
624	return pkt_info->desc_count;
625
626err_out:
627	while (start_index < cur_index) {
628		desc_data = XLGMAC_GET_DESC_DATA(ring, start_index++);
629		xlgmac_unmap_desc_data(pdata, desc_data);
630	}
631
632	return 0;
633}
634
635void xlgmac_init_desc_ops(struct xlgmac_desc_ops *desc_ops)
636{
637	desc_ops->alloc_channels_and_rings = xlgmac_alloc_channels_and_rings;
638	desc_ops->free_channels_and_rings = xlgmac_free_channels_and_rings;
639	desc_ops->map_tx_skb = xlgmac_map_tx_skb;
640	desc_ops->map_rx_buffer = xlgmac_map_rx_buffer;
641	desc_ops->unmap_desc_data = xlgmac_unmap_desc_data;
642	desc_ops->tx_desc_init = xlgmac_tx_desc_init;
643	desc_ops->rx_desc_init = xlgmac_rx_desc_init;
644}
645