1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Actions Semi Owl SoCs Ethernet MAC driver
4 *
5 * Copyright (c) 2012 Actions Semi Inc.
6 * Copyright (c) 2021 Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
7 */
8
9#include <linux/circ_buf.h>
10#include <linux/clk.h>
11#include <linux/dma-mapping.h>
12#include <linux/etherdevice.h>
13#include <linux/of_mdio.h>
14#include <linux/of_net.h>
15#include <linux/platform_device.h>
16#include <linux/pm.h>
17#include <linux/reset.h>
18
19#include "owl-emac.h"
20
21#define OWL_EMAC_DEFAULT_MSG_ENABLE	(NETIF_MSG_DRV | \
22					 NETIF_MSG_PROBE | \
23					 NETIF_MSG_LINK)
24
25static u32 owl_emac_reg_read(struct owl_emac_priv *priv, u32 reg)
26{
27	return readl(priv->base + reg);
28}
29
30static void owl_emac_reg_write(struct owl_emac_priv *priv, u32 reg, u32 data)
31{
32	writel(data, priv->base + reg);
33}
34
35static u32 owl_emac_reg_update(struct owl_emac_priv *priv,
36			       u32 reg, u32 mask, u32 val)
37{
38	u32 data, old_val;
39
40	data = owl_emac_reg_read(priv, reg);
41	old_val = data & mask;
42
43	data &= ~mask;
44	data |= val & mask;
45
46	owl_emac_reg_write(priv, reg, data);
47
48	return old_val;
49}
50
51static void owl_emac_reg_set(struct owl_emac_priv *priv, u32 reg, u32 bits)
52{
53	owl_emac_reg_update(priv, reg, bits, bits);
54}
55
56static void owl_emac_reg_clear(struct owl_emac_priv *priv, u32 reg, u32 bits)
57{
58	owl_emac_reg_update(priv, reg, bits, 0);
59}
60
61static struct device *owl_emac_get_dev(struct owl_emac_priv *priv)
62{
63	return priv->netdev->dev.parent;
64}
65
66static void owl_emac_irq_enable(struct owl_emac_priv *priv)
67{
68	/* Enable all interrupts except TU.
69	 *
70	 * Note the NIE and AIE bits shall also be set in order to actually
71	 * enable the selected interrupts.
72	 */
73	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR7,
74			   OWL_EMAC_BIT_MAC_CSR7_NIE |
75			   OWL_EMAC_BIT_MAC_CSR7_AIE |
76			   OWL_EMAC_BIT_MAC_CSR7_ALL_NOT_TUE);
77}
78
79static void owl_emac_irq_disable(struct owl_emac_priv *priv)
80{
81	/* Disable all interrupts.
82	 *
83	 * WARNING: Unset only the NIE and AIE bits in CSR7 to workaround an
84	 * unexpected side effect (MAC hardware bug?!) where some bits in the
85	 * status register (CSR5) are cleared automatically before being able
86	 * to read them via owl_emac_irq_clear().
87	 */
88	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR7,
89			   OWL_EMAC_BIT_MAC_CSR7_ALL_NOT_TUE);
90}
91
92static u32 owl_emac_irq_status(struct owl_emac_priv *priv)
93{
94	return owl_emac_reg_read(priv, OWL_EMAC_REG_MAC_CSR5);
95}
96
97static u32 owl_emac_irq_clear(struct owl_emac_priv *priv)
98{
99	u32 val = owl_emac_irq_status(priv);
100
101	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR5, val);
102
103	return val;
104}
105
106static dma_addr_t owl_emac_dma_map_rx(struct owl_emac_priv *priv,
107				      struct sk_buff *skb)
108{
109	struct device *dev = owl_emac_get_dev(priv);
110
111	/* Buffer pointer for the RX DMA descriptor must be word aligned. */
112	return dma_map_single(dev, skb_tail_pointer(skb),
113			      skb_tailroom(skb), DMA_FROM_DEVICE);
114}
115
116static void owl_emac_dma_unmap_rx(struct owl_emac_priv *priv,
117				  struct sk_buff *skb, dma_addr_t dma_addr)
118{
119	struct device *dev = owl_emac_get_dev(priv);
120
121	dma_unmap_single(dev, dma_addr, skb_tailroom(skb), DMA_FROM_DEVICE);
122}
123
124static dma_addr_t owl_emac_dma_map_tx(struct owl_emac_priv *priv,
125				      struct sk_buff *skb)
126{
127	struct device *dev = owl_emac_get_dev(priv);
128
129	return dma_map_single(dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
130}
131
132static void owl_emac_dma_unmap_tx(struct owl_emac_priv *priv,
133				  struct sk_buff *skb, dma_addr_t dma_addr)
134{
135	struct device *dev = owl_emac_get_dev(priv);
136
137	dma_unmap_single(dev, dma_addr, skb_headlen(skb), DMA_TO_DEVICE);
138}
139
140static unsigned int owl_emac_ring_num_unused(struct owl_emac_ring *ring)
141{
142	return CIRC_SPACE(ring->head, ring->tail, ring->size);
143}
144
145static unsigned int owl_emac_ring_get_next(struct owl_emac_ring *ring,
146					   unsigned int cur)
147{
148	return (cur + 1) & (ring->size - 1);
149}
150
151static void owl_emac_ring_push_head(struct owl_emac_ring *ring)
152{
153	ring->head = owl_emac_ring_get_next(ring, ring->head);
154}
155
156static void owl_emac_ring_pop_tail(struct owl_emac_ring *ring)
157{
158	ring->tail = owl_emac_ring_get_next(ring, ring->tail);
159}
160
161static struct sk_buff *owl_emac_alloc_skb(struct net_device *netdev)
162{
163	struct sk_buff *skb;
164	int offset;
165
166	skb = netdev_alloc_skb(netdev, OWL_EMAC_RX_FRAME_MAX_LEN +
167			       OWL_EMAC_SKB_RESERVE);
168	if (unlikely(!skb))
169		return NULL;
170
171	/* Ensure 4 bytes DMA alignment. */
172	offset = ((uintptr_t)skb->data) & (OWL_EMAC_SKB_ALIGN - 1);
173	if (unlikely(offset))
174		skb_reserve(skb, OWL_EMAC_SKB_ALIGN - offset);
175
176	return skb;
177}
178
179static int owl_emac_ring_prepare_rx(struct owl_emac_priv *priv)
180{
181	struct owl_emac_ring *ring = &priv->rx_ring;
182	struct device *dev = owl_emac_get_dev(priv);
183	struct net_device *netdev = priv->netdev;
184	struct owl_emac_ring_desc *desc;
185	struct sk_buff *skb;
186	dma_addr_t dma_addr;
187	int i;
188
189	for (i = 0; i < ring->size; i++) {
190		skb = owl_emac_alloc_skb(netdev);
191		if (!skb)
192			return -ENOMEM;
193
194		dma_addr = owl_emac_dma_map_rx(priv, skb);
195		if (dma_mapping_error(dev, dma_addr)) {
196			dev_kfree_skb(skb);
197			return -ENOMEM;
198		}
199
200		desc = &ring->descs[i];
201		desc->status = OWL_EMAC_BIT_RDES0_OWN;
202		desc->control = skb_tailroom(skb) & OWL_EMAC_MSK_RDES1_RBS1;
203		desc->buf_addr = dma_addr;
204		desc->reserved = 0;
205
206		ring->skbs[i] = skb;
207		ring->skbs_dma[i] = dma_addr;
208	}
209
210	desc->control |= OWL_EMAC_BIT_RDES1_RER;
211
212	ring->head = 0;
213	ring->tail = 0;
214
215	return 0;
216}
217
218static void owl_emac_ring_prepare_tx(struct owl_emac_priv *priv)
219{
220	struct owl_emac_ring *ring = &priv->tx_ring;
221	struct owl_emac_ring_desc *desc;
222	int i;
223
224	for (i = 0; i < ring->size; i++) {
225		desc = &ring->descs[i];
226
227		desc->status = 0;
228		desc->control = OWL_EMAC_BIT_TDES1_IC;
229		desc->buf_addr = 0;
230		desc->reserved = 0;
231	}
232
233	desc->control |= OWL_EMAC_BIT_TDES1_TER;
234
235	memset(ring->skbs_dma, 0, sizeof(dma_addr_t) * ring->size);
236
237	ring->head = 0;
238	ring->tail = 0;
239}
240
241static void owl_emac_ring_unprepare_rx(struct owl_emac_priv *priv)
242{
243	struct owl_emac_ring *ring = &priv->rx_ring;
244	int i;
245
246	for (i = 0; i < ring->size; i++) {
247		ring->descs[i].status = 0;
248
249		if (!ring->skbs_dma[i])
250			continue;
251
252		owl_emac_dma_unmap_rx(priv, ring->skbs[i], ring->skbs_dma[i]);
253		ring->skbs_dma[i] = 0;
254
255		dev_kfree_skb(ring->skbs[i]);
256		ring->skbs[i] = NULL;
257	}
258}
259
260static void owl_emac_ring_unprepare_tx(struct owl_emac_priv *priv)
261{
262	struct owl_emac_ring *ring = &priv->tx_ring;
263	int i;
264
265	for (i = 0; i < ring->size; i++) {
266		ring->descs[i].status = 0;
267
268		if (!ring->skbs_dma[i])
269			continue;
270
271		owl_emac_dma_unmap_tx(priv, ring->skbs[i], ring->skbs_dma[i]);
272		ring->skbs_dma[i] = 0;
273
274		dev_kfree_skb(ring->skbs[i]);
275		ring->skbs[i] = NULL;
276	}
277}
278
279static int owl_emac_ring_alloc(struct device *dev, struct owl_emac_ring *ring,
280			       unsigned int size)
281{
282	ring->descs = dmam_alloc_coherent(dev,
283					  sizeof(struct owl_emac_ring_desc) * size,
284					  &ring->descs_dma, GFP_KERNEL);
285	if (!ring->descs)
286		return -ENOMEM;
287
288	ring->skbs = devm_kcalloc(dev, size, sizeof(struct sk_buff *),
289				  GFP_KERNEL);
290	if (!ring->skbs)
291		return -ENOMEM;
292
293	ring->skbs_dma = devm_kcalloc(dev, size, sizeof(dma_addr_t),
294				      GFP_KERNEL);
295	if (!ring->skbs_dma)
296		return -ENOMEM;
297
298	ring->size = size;
299
300	return 0;
301}
302
303static void owl_emac_dma_cmd_resume_rx(struct owl_emac_priv *priv)
304{
305	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR2,
306			   OWL_EMAC_VAL_MAC_CSR2_RPD);
307}
308
309static void owl_emac_dma_cmd_resume_tx(struct owl_emac_priv *priv)
310{
311	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR1,
312			   OWL_EMAC_VAL_MAC_CSR1_TPD);
313}
314
315static u32 owl_emac_dma_cmd_set_tx(struct owl_emac_priv *priv, u32 status)
316{
317	return owl_emac_reg_update(priv, OWL_EMAC_REG_MAC_CSR6,
318				   OWL_EMAC_BIT_MAC_CSR6_ST, status);
319}
320
321static u32 owl_emac_dma_cmd_start_tx(struct owl_emac_priv *priv)
322{
323	return owl_emac_dma_cmd_set_tx(priv, ~0);
324}
325
326static u32 owl_emac_dma_cmd_set(struct owl_emac_priv *priv, u32 status)
327{
328	return owl_emac_reg_update(priv, OWL_EMAC_REG_MAC_CSR6,
329				   OWL_EMAC_MSK_MAC_CSR6_STSR, status);
330}
331
332static u32 owl_emac_dma_cmd_start(struct owl_emac_priv *priv)
333{
334	return owl_emac_dma_cmd_set(priv, ~0);
335}
336
337static u32 owl_emac_dma_cmd_stop(struct owl_emac_priv *priv)
338{
339	return owl_emac_dma_cmd_set(priv, 0);
340}
341
342static void owl_emac_set_hw_mac_addr(struct net_device *netdev)
343{
344	struct owl_emac_priv *priv = netdev_priv(netdev);
345	const u8 *mac_addr = netdev->dev_addr;
346	u32 addr_high, addr_low;
347
348	addr_high = mac_addr[0] << 8 | mac_addr[1];
349	addr_low = mac_addr[2] << 24 | mac_addr[3] << 16 |
350		   mac_addr[4] << 8 | mac_addr[5];
351
352	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR17, addr_high);
353	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR16, addr_low);
354}
355
356static void owl_emac_update_link_state(struct owl_emac_priv *priv)
357{
358	u32 val, status;
359
360	if (priv->pause) {
361		val = OWL_EMAC_BIT_MAC_CSR20_FCE | OWL_EMAC_BIT_MAC_CSR20_TUE;
362		val |= OWL_EMAC_BIT_MAC_CSR20_TPE | OWL_EMAC_BIT_MAC_CSR20_RPE;
363		val |= OWL_EMAC_BIT_MAC_CSR20_BPE;
364	} else {
365		val = 0;
366	}
367
368	/* Update flow control. */
369	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR20, val);
370
371	val = (priv->speed == SPEED_100) ? OWL_EMAC_VAL_MAC_CSR6_SPEED_100M :
372					   OWL_EMAC_VAL_MAC_CSR6_SPEED_10M;
373	val <<= OWL_EMAC_OFF_MAC_CSR6_SPEED;
374
375	if (priv->duplex == DUPLEX_FULL)
376		val |= OWL_EMAC_BIT_MAC_CSR6_FD;
377
378	spin_lock_bh(&priv->lock);
379
380	/* Temporarily stop DMA TX & RX. */
381	status = owl_emac_dma_cmd_stop(priv);
382
383	/* Update operation modes. */
384	owl_emac_reg_update(priv, OWL_EMAC_REG_MAC_CSR6,
385			    OWL_EMAC_MSK_MAC_CSR6_SPEED |
386			    OWL_EMAC_BIT_MAC_CSR6_FD, val);
387
388	/* Restore DMA TX & RX status. */
389	owl_emac_dma_cmd_set(priv, status);
390
391	spin_unlock_bh(&priv->lock);
392}
393
394static void owl_emac_adjust_link(struct net_device *netdev)
395{
396	struct owl_emac_priv *priv = netdev_priv(netdev);
397	struct phy_device *phydev = netdev->phydev;
398	bool state_changed = false;
399
400	if (phydev->link) {
401		if (!priv->link) {
402			priv->link = phydev->link;
403			state_changed = true;
404		}
405
406		if (priv->speed != phydev->speed) {
407			priv->speed = phydev->speed;
408			state_changed = true;
409		}
410
411		if (priv->duplex != phydev->duplex) {
412			priv->duplex = phydev->duplex;
413			state_changed = true;
414		}
415
416		if (priv->pause != phydev->pause) {
417			priv->pause = phydev->pause;
418			state_changed = true;
419		}
420	} else {
421		if (priv->link) {
422			priv->link = phydev->link;
423			state_changed = true;
424		}
425	}
426
427	if (state_changed) {
428		if (phydev->link)
429			owl_emac_update_link_state(priv);
430
431		if (netif_msg_link(priv))
432			phy_print_status(phydev);
433	}
434}
435
436static irqreturn_t owl_emac_handle_irq(int irq, void *data)
437{
438	struct net_device *netdev = data;
439	struct owl_emac_priv *priv = netdev_priv(netdev);
440
441	if (netif_running(netdev)) {
442		owl_emac_irq_disable(priv);
443		napi_schedule(&priv->napi);
444	}
445
446	return IRQ_HANDLED;
447}
448
449static void owl_emac_ether_addr_push(u8 **dst, const u8 *src)
450{
451	u32 *a = (u32 *)(*dst);
452	const u16 *b = (const u16 *)src;
453
454	a[0] = b[0];
455	a[1] = b[1];
456	a[2] = b[2];
457
458	*dst += 12;
459}
460
461static void
462owl_emac_setup_frame_prepare(struct owl_emac_priv *priv, struct sk_buff *skb)
463{
464	const u8 bcast_addr[] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
465	const u8 *mac_addr = priv->netdev->dev_addr;
466	u8 *frame;
467	int i;
468
469	skb_put(skb, OWL_EMAC_SETUP_FRAME_LEN);
470
471	frame = skb->data;
472	memset(frame, 0, skb->len);
473
474	owl_emac_ether_addr_push(&frame, mac_addr);
475	owl_emac_ether_addr_push(&frame, bcast_addr);
476
477	/* Fill multicast addresses. */
478	WARN_ON(priv->mcaddr_list.count >= OWL_EMAC_MAX_MULTICAST_ADDRS);
479	for (i = 0; i < priv->mcaddr_list.count; i++) {
480		mac_addr = priv->mcaddr_list.addrs[i];
481		owl_emac_ether_addr_push(&frame, mac_addr);
482	}
483}
484
485/* The setup frame is a special descriptor which is used to provide physical
486 * addresses (i.e. mac, broadcast and multicast) to the MAC hardware for
487 * filtering purposes. To be recognized as a setup frame, the TDES1_SET bit
488 * must be set in the TX descriptor control field.
489 */
490static int owl_emac_setup_frame_xmit(struct owl_emac_priv *priv)
491{
492	struct owl_emac_ring *ring = &priv->tx_ring;
493	struct net_device *netdev = priv->netdev;
494	struct owl_emac_ring_desc *desc;
495	struct sk_buff *skb;
496	unsigned int tx_head;
497	u32 status, control;
498	dma_addr_t dma_addr;
499	int ret;
500
501	skb = owl_emac_alloc_skb(netdev);
502	if (!skb)
503		return -ENOMEM;
504
505	owl_emac_setup_frame_prepare(priv, skb);
506
507	dma_addr = owl_emac_dma_map_tx(priv, skb);
508	if (dma_mapping_error(owl_emac_get_dev(priv), dma_addr)) {
509		ret = -ENOMEM;
510		goto err_free_skb;
511	}
512
513	spin_lock_bh(&priv->lock);
514
515	tx_head = ring->head;
516	desc = &ring->descs[tx_head];
517
518	status = READ_ONCE(desc->status);
519	control = READ_ONCE(desc->control);
520	dma_rmb(); /* Ensure data has been read before used. */
521
522	if (unlikely(status & OWL_EMAC_BIT_TDES0_OWN) ||
523	    !owl_emac_ring_num_unused(ring)) {
524		spin_unlock_bh(&priv->lock);
525		owl_emac_dma_unmap_tx(priv, skb, dma_addr);
526		ret = -EBUSY;
527		goto err_free_skb;
528	}
529
530	ring->skbs[tx_head] = skb;
531	ring->skbs_dma[tx_head] = dma_addr;
532
533	control &= OWL_EMAC_BIT_TDES1_IC | OWL_EMAC_BIT_TDES1_TER; /* Maintain bits */
534	control |= OWL_EMAC_BIT_TDES1_SET;
535	control |= OWL_EMAC_MSK_TDES1_TBS1 & skb->len;
536
537	WRITE_ONCE(desc->control, control);
538	WRITE_ONCE(desc->buf_addr, dma_addr);
539	dma_wmb(); /* Flush descriptor before changing ownership. */
540	WRITE_ONCE(desc->status, OWL_EMAC_BIT_TDES0_OWN);
541
542	owl_emac_ring_push_head(ring);
543
544	/* Temporarily enable DMA TX. */
545	status = owl_emac_dma_cmd_start_tx(priv);
546
547	/* Trigger setup frame processing. */
548	owl_emac_dma_cmd_resume_tx(priv);
549
550	/* Restore DMA TX status. */
551	owl_emac_dma_cmd_set_tx(priv, status);
552
553	/* Stop regular TX until setup frame is processed. */
554	netif_stop_queue(netdev);
555
556	spin_unlock_bh(&priv->lock);
557
558	return 0;
559
560err_free_skb:
561	dev_kfree_skb(skb);
562	return ret;
563}
564
565static netdev_tx_t owl_emac_ndo_start_xmit(struct sk_buff *skb,
566					   struct net_device *netdev)
567{
568	struct owl_emac_priv *priv = netdev_priv(netdev);
569	struct device *dev = owl_emac_get_dev(priv);
570	struct owl_emac_ring *ring = &priv->tx_ring;
571	struct owl_emac_ring_desc *desc;
572	unsigned int tx_head;
573	u32 status, control;
574	dma_addr_t dma_addr;
575
576	dma_addr = owl_emac_dma_map_tx(priv, skb);
577	if (dma_mapping_error(dev, dma_addr)) {
578		dev_err_ratelimited(&netdev->dev, "TX DMA mapping failed\n");
579		dev_kfree_skb(skb);
580		netdev->stats.tx_dropped++;
581		return NETDEV_TX_OK;
582	}
583
584	spin_lock_bh(&priv->lock);
585
586	tx_head = ring->head;
587	desc = &ring->descs[tx_head];
588
589	status = READ_ONCE(desc->status);
590	control = READ_ONCE(desc->control);
591	dma_rmb(); /* Ensure data has been read before used. */
592
593	if (!owl_emac_ring_num_unused(ring) ||
594	    unlikely(status & OWL_EMAC_BIT_TDES0_OWN)) {
595		netif_stop_queue(netdev);
596		spin_unlock_bh(&priv->lock);
597
598		dev_dbg_ratelimited(&netdev->dev, "TX buffer full, status=0x%08x\n",
599				    owl_emac_irq_status(priv));
600		owl_emac_dma_unmap_tx(priv, skb, dma_addr);
601		netdev->stats.tx_dropped++;
602		return NETDEV_TX_BUSY;
603	}
604
605	ring->skbs[tx_head] = skb;
606	ring->skbs_dma[tx_head] = dma_addr;
607
608	control &= OWL_EMAC_BIT_TDES1_IC | OWL_EMAC_BIT_TDES1_TER; /* Maintain bits */
609	control |= OWL_EMAC_BIT_TDES1_FS | OWL_EMAC_BIT_TDES1_LS;
610	control |= OWL_EMAC_MSK_TDES1_TBS1 & skb->len;
611
612	WRITE_ONCE(desc->control, control);
613	WRITE_ONCE(desc->buf_addr, dma_addr);
614	dma_wmb(); /* Flush descriptor before changing ownership. */
615	WRITE_ONCE(desc->status, OWL_EMAC_BIT_TDES0_OWN);
616
617	owl_emac_dma_cmd_resume_tx(priv);
618	owl_emac_ring_push_head(ring);
619
620	/* FIXME: The transmission is currently restricted to a single frame
621	 * at a time as a workaround for a MAC hardware bug that causes random
622	 * freeze of the TX queue processor.
623	 */
624	netif_stop_queue(netdev);
625
626	spin_unlock_bh(&priv->lock);
627
628	return NETDEV_TX_OK;
629}
630
631static bool owl_emac_tx_complete_tail(struct owl_emac_priv *priv)
632{
633	struct owl_emac_ring *ring = &priv->tx_ring;
634	struct net_device *netdev = priv->netdev;
635	struct owl_emac_ring_desc *desc;
636	struct sk_buff *skb;
637	unsigned int tx_tail;
638	u32 status;
639
640	tx_tail = ring->tail;
641	desc = &ring->descs[tx_tail];
642
643	status = READ_ONCE(desc->status);
644	dma_rmb(); /* Ensure data has been read before used. */
645
646	if (status & OWL_EMAC_BIT_TDES0_OWN)
647		return false;
648
649	/* Check for errors. */
650	if (status & OWL_EMAC_BIT_TDES0_ES) {
651		dev_dbg_ratelimited(&netdev->dev,
652				    "TX complete error status: 0x%08x\n",
653				    status);
654
655		netdev->stats.tx_errors++;
656
657		if (status & OWL_EMAC_BIT_TDES0_UF)
658			netdev->stats.tx_fifo_errors++;
659
660		if (status & OWL_EMAC_BIT_TDES0_EC)
661			netdev->stats.tx_aborted_errors++;
662
663		if (status & OWL_EMAC_BIT_TDES0_LC)
664			netdev->stats.tx_window_errors++;
665
666		if (status & OWL_EMAC_BIT_TDES0_NC)
667			netdev->stats.tx_heartbeat_errors++;
668
669		if (status & OWL_EMAC_BIT_TDES0_LO)
670			netdev->stats.tx_carrier_errors++;
671	} else {
672		netdev->stats.tx_packets++;
673		netdev->stats.tx_bytes += ring->skbs[tx_tail]->len;
674	}
675
676	/* Some collisions occurred, but pkt has been transmitted. */
677	if (status & OWL_EMAC_BIT_TDES0_DE)
678		netdev->stats.collisions++;
679
680	skb = ring->skbs[tx_tail];
681	owl_emac_dma_unmap_tx(priv, skb, ring->skbs_dma[tx_tail]);
682	dev_kfree_skb(skb);
683
684	ring->skbs[tx_tail] = NULL;
685	ring->skbs_dma[tx_tail] = 0;
686
687	owl_emac_ring_pop_tail(ring);
688
689	if (unlikely(netif_queue_stopped(netdev)))
690		netif_wake_queue(netdev);
691
692	return true;
693}
694
695static void owl_emac_tx_complete(struct owl_emac_priv *priv)
696{
697	struct owl_emac_ring *ring = &priv->tx_ring;
698	struct net_device *netdev = priv->netdev;
699	unsigned int tx_next;
700	u32 status;
701
702	spin_lock(&priv->lock);
703
704	while (ring->tail != ring->head) {
705		if (!owl_emac_tx_complete_tail(priv))
706			break;
707	}
708
709	/* FIXME: This is a workaround for a MAC hardware bug not clearing
710	 * (sometimes) the OWN bit for a transmitted frame descriptor.
711	 *
712	 * At this point, when TX queue is full, the tail descriptor has the
713	 * OWN bit set, which normally means the frame has not been processed
714	 * or transmitted yet. But if there is at least one descriptor in the
715	 * queue having the OWN bit cleared, we can safely assume the tail
716	 * frame has been also processed by the MAC hardware.
717	 *
718	 * If that's the case, let's force the frame completion by manually
719	 * clearing the OWN bit.
720	 */
721	if (unlikely(!owl_emac_ring_num_unused(ring))) {
722		tx_next = ring->tail;
723
724		while ((tx_next = owl_emac_ring_get_next(ring, tx_next)) != ring->head) {
725			status = READ_ONCE(ring->descs[tx_next].status);
726			dma_rmb(); /* Ensure data has been read before used. */
727
728			if (status & OWL_EMAC_BIT_TDES0_OWN)
729				continue;
730
731			netdev_dbg(netdev, "Found uncleared TX desc OWN bit\n");
732
733			status = READ_ONCE(ring->descs[ring->tail].status);
734			dma_rmb(); /* Ensure data has been read before used. */
735			status &= ~OWL_EMAC_BIT_TDES0_OWN;
736			WRITE_ONCE(ring->descs[ring->tail].status, status);
737
738			owl_emac_tx_complete_tail(priv);
739			break;
740		}
741	}
742
743	spin_unlock(&priv->lock);
744}
745
746static int owl_emac_rx_process(struct owl_emac_priv *priv, int budget)
747{
748	struct owl_emac_ring *ring = &priv->rx_ring;
749	struct device *dev = owl_emac_get_dev(priv);
750	struct net_device *netdev = priv->netdev;
751	struct owl_emac_ring_desc *desc;
752	struct sk_buff *curr_skb, *new_skb;
753	dma_addr_t curr_dma, new_dma;
754	unsigned int rx_tail, len;
755	u32 status;
756	int recv = 0;
757
758	while (recv < budget) {
759		spin_lock(&priv->lock);
760
761		rx_tail = ring->tail;
762		desc = &ring->descs[rx_tail];
763
764		status = READ_ONCE(desc->status);
765		dma_rmb(); /* Ensure data has been read before used. */
766
767		if (status & OWL_EMAC_BIT_RDES0_OWN) {
768			spin_unlock(&priv->lock);
769			break;
770		}
771
772		curr_skb = ring->skbs[rx_tail];
773		curr_dma = ring->skbs_dma[rx_tail];
774		owl_emac_ring_pop_tail(ring);
775
776		spin_unlock(&priv->lock);
777
778		if (status & (OWL_EMAC_BIT_RDES0_DE | OWL_EMAC_BIT_RDES0_RF |
779		    OWL_EMAC_BIT_RDES0_TL | OWL_EMAC_BIT_RDES0_CS |
780		    OWL_EMAC_BIT_RDES0_DB | OWL_EMAC_BIT_RDES0_CE |
781		    OWL_EMAC_BIT_RDES0_ZERO)) {
782			dev_dbg_ratelimited(&netdev->dev,
783					    "RX desc error status: 0x%08x\n",
784					    status);
785
786			if (status & OWL_EMAC_BIT_RDES0_DE)
787				netdev->stats.rx_over_errors++;
788
789			if (status & (OWL_EMAC_BIT_RDES0_RF | OWL_EMAC_BIT_RDES0_DB))
790				netdev->stats.rx_frame_errors++;
791
792			if (status & OWL_EMAC_BIT_RDES0_TL)
793				netdev->stats.rx_length_errors++;
794
795			if (status & OWL_EMAC_BIT_RDES0_CS)
796				netdev->stats.collisions++;
797
798			if (status & OWL_EMAC_BIT_RDES0_CE)
799				netdev->stats.rx_crc_errors++;
800
801			if (status & OWL_EMAC_BIT_RDES0_ZERO)
802				netdev->stats.rx_fifo_errors++;
803
804			goto drop_skb;
805		}
806
807		len = (status & OWL_EMAC_MSK_RDES0_FL) >> OWL_EMAC_OFF_RDES0_FL;
808		if (unlikely(len > OWL_EMAC_RX_FRAME_MAX_LEN)) {
809			netdev->stats.rx_length_errors++;
810			netdev_err(netdev, "invalid RX frame len: %u\n", len);
811			goto drop_skb;
812		}
813
814		/* Prepare new skb before receiving the current one. */
815		new_skb = owl_emac_alloc_skb(netdev);
816		if (unlikely(!new_skb))
817			goto drop_skb;
818
819		new_dma = owl_emac_dma_map_rx(priv, new_skb);
820		if (dma_mapping_error(dev, new_dma)) {
821			dev_kfree_skb(new_skb);
822			netdev_err(netdev, "RX DMA mapping failed\n");
823			goto drop_skb;
824		}
825
826		owl_emac_dma_unmap_rx(priv, curr_skb, curr_dma);
827
828		skb_put(curr_skb, len - ETH_FCS_LEN);
829		curr_skb->ip_summed = CHECKSUM_NONE;
830		curr_skb->protocol = eth_type_trans(curr_skb, netdev);
831		curr_skb->dev = netdev;
832
833		netif_receive_skb(curr_skb);
834
835		netdev->stats.rx_packets++;
836		netdev->stats.rx_bytes += len;
837		recv++;
838		goto push_skb;
839
840drop_skb:
841		netdev->stats.rx_dropped++;
842		netdev->stats.rx_errors++;
843		/* Reuse the current skb. */
844		new_skb = curr_skb;
845		new_dma = curr_dma;
846
847push_skb:
848		spin_lock(&priv->lock);
849
850		ring->skbs[ring->head] = new_skb;
851		ring->skbs_dma[ring->head] = new_dma;
852
853		WRITE_ONCE(desc->buf_addr, new_dma);
854		dma_wmb(); /* Flush descriptor before changing ownership. */
855		WRITE_ONCE(desc->status, OWL_EMAC_BIT_RDES0_OWN);
856
857		owl_emac_ring_push_head(ring);
858
859		spin_unlock(&priv->lock);
860	}
861
862	return recv;
863}
864
865static int owl_emac_poll(struct napi_struct *napi, int budget)
866{
867	int work_done = 0, ru_cnt = 0, recv;
868	static int tx_err_cnt, rx_err_cnt;
869	struct owl_emac_priv *priv;
870	u32 status, proc_status;
871
872	priv = container_of(napi, struct owl_emac_priv, napi);
873
874	while ((status = owl_emac_irq_clear(priv)) &
875	       (OWL_EMAC_BIT_MAC_CSR5_NIS | OWL_EMAC_BIT_MAC_CSR5_AIS)) {
876		recv = 0;
877
878		/* TX setup frame raises ETI instead of TI. */
879		if (status & (OWL_EMAC_BIT_MAC_CSR5_TI | OWL_EMAC_BIT_MAC_CSR5_ETI)) {
880			owl_emac_tx_complete(priv);
881			tx_err_cnt = 0;
882
883			/* Count MAC internal RX errors. */
884			proc_status = status & OWL_EMAC_MSK_MAC_CSR5_RS;
885			proc_status >>= OWL_EMAC_OFF_MAC_CSR5_RS;
886			if (proc_status == OWL_EMAC_VAL_MAC_CSR5_RS_DATA ||
887			    proc_status == OWL_EMAC_VAL_MAC_CSR5_RS_CDES ||
888			    proc_status == OWL_EMAC_VAL_MAC_CSR5_RS_FDES)
889				rx_err_cnt++;
890		}
891
892		if (status & OWL_EMAC_BIT_MAC_CSR5_RI) {
893			recv = owl_emac_rx_process(priv, budget - work_done);
894			rx_err_cnt = 0;
895
896			/* Count MAC internal TX errors. */
897			proc_status = status & OWL_EMAC_MSK_MAC_CSR5_TS;
898			proc_status >>= OWL_EMAC_OFF_MAC_CSR5_TS;
899			if (proc_status == OWL_EMAC_VAL_MAC_CSR5_TS_DATA ||
900			    proc_status == OWL_EMAC_VAL_MAC_CSR5_TS_CDES)
901				tx_err_cnt++;
902		} else if (status & OWL_EMAC_BIT_MAC_CSR5_RU) {
903			/* MAC AHB is in suspended state, will return to RX
904			 * descriptor processing when the host changes ownership
905			 * of the descriptor and either an RX poll demand CMD is
906			 * issued or a new frame is recognized by the MAC AHB.
907			 */
908			if (++ru_cnt == 2)
909				owl_emac_dma_cmd_resume_rx(priv);
910
911			recv = owl_emac_rx_process(priv, budget - work_done);
912
913			/* Guard against too many RU interrupts. */
914			if (ru_cnt > 3)
915				break;
916		}
917
918		work_done += recv;
919		if (work_done >= budget)
920			break;
921	}
922
923	if (work_done < budget) {
924		napi_complete_done(napi, work_done);
925		owl_emac_irq_enable(priv);
926	}
927
928	/* Reset MAC when getting too many internal TX or RX errors. */
929	if (tx_err_cnt > 10 || rx_err_cnt > 10) {
930		netdev_dbg(priv->netdev, "%s error status: 0x%08x\n",
931			   tx_err_cnt > 10 ? "TX" : "RX", status);
932		rx_err_cnt = 0;
933		tx_err_cnt = 0;
934		schedule_work(&priv->mac_reset_task);
935	}
936
937	return work_done;
938}
939
940static void owl_emac_mdio_clock_enable(struct owl_emac_priv *priv)
941{
942	u32 val;
943
944	/* Enable MDC clock generation by adjusting CLKDIV according to
945	 * the vendor implementation of the original driver.
946	 */
947	val = owl_emac_reg_read(priv, OWL_EMAC_REG_MAC_CSR10);
948	val &= OWL_EMAC_MSK_MAC_CSR10_CLKDIV;
949	val |= OWL_EMAC_VAL_MAC_CSR10_CLKDIV_128 << OWL_EMAC_OFF_MAC_CSR10_CLKDIV;
950
951	val |= OWL_EMAC_BIT_MAC_CSR10_SB;
952	val |= OWL_EMAC_VAL_MAC_CSR10_OPCODE_CDS << OWL_EMAC_OFF_MAC_CSR10_OPCODE;
953	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR10, val);
954}
955
956static void owl_emac_core_hw_reset(struct owl_emac_priv *priv)
957{
958	/* Trigger hardware reset. */
959	reset_control_assert(priv->reset);
960	usleep_range(10, 20);
961	reset_control_deassert(priv->reset);
962	usleep_range(100, 200);
963}
964
965static int owl_emac_core_sw_reset(struct owl_emac_priv *priv)
966{
967	u32 val;
968	int ret;
969
970	/* Trigger software reset. */
971	owl_emac_reg_set(priv, OWL_EMAC_REG_MAC_CSR0, OWL_EMAC_BIT_MAC_CSR0_SWR);
972	ret = readl_poll_timeout(priv->base + OWL_EMAC_REG_MAC_CSR0,
973				 val, !(val & OWL_EMAC_BIT_MAC_CSR0_SWR),
974				 OWL_EMAC_POLL_DELAY_USEC,
975				 OWL_EMAC_RESET_POLL_TIMEOUT_USEC);
976	if (ret)
977		return ret;
978
979	if (priv->phy_mode == PHY_INTERFACE_MODE_RMII) {
980		/* Enable RMII and use the 50MHz rmii clk as output to PHY. */
981		val = 0;
982	} else {
983		/* Enable SMII and use the 125MHz rmii clk as output to PHY.
984		 * Additionally set SMII SYNC delay to 4 half cycle.
985		 */
986		val = 0x04 << OWL_EMAC_OFF_MAC_CTRL_SSDC;
987		val |= OWL_EMAC_BIT_MAC_CTRL_RSIS;
988	}
989	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CTRL, val);
990
991	/* MDC is disabled after reset. */
992	owl_emac_mdio_clock_enable(priv);
993
994	/* Set FIFO pause & restart threshold levels. */
995	val = 0x40 << OWL_EMAC_OFF_MAC_CSR19_FPTL;
996	val |= 0x10 << OWL_EMAC_OFF_MAC_CSR19_FRTL;
997	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR19, val);
998
999	/* Set flow control pause quanta time to ~100 ms. */
1000	val = 0x4FFF << OWL_EMAC_OFF_MAC_CSR18_PQT;
1001	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR18, val);
1002
1003	/* Setup interrupt mitigation. */
1004	val = 7 << OWL_EMAC_OFF_MAC_CSR11_NRP;
1005	val |= 4 << OWL_EMAC_OFF_MAC_CSR11_RT;
1006	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR11, val);
1007
1008	/* Set RX/TX rings base addresses. */
1009	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR3,
1010			   (u32)(priv->rx_ring.descs_dma));
1011	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR4,
1012			   (u32)(priv->tx_ring.descs_dma));
1013
1014	/* Setup initial operation mode. */
1015	val = OWL_EMAC_VAL_MAC_CSR6_SPEED_100M << OWL_EMAC_OFF_MAC_CSR6_SPEED;
1016	val |= OWL_EMAC_BIT_MAC_CSR6_FD;
1017	owl_emac_reg_update(priv, OWL_EMAC_REG_MAC_CSR6,
1018			    OWL_EMAC_MSK_MAC_CSR6_SPEED |
1019			    OWL_EMAC_BIT_MAC_CSR6_FD, val);
1020	owl_emac_reg_clear(priv, OWL_EMAC_REG_MAC_CSR6,
1021			   OWL_EMAC_BIT_MAC_CSR6_PR | OWL_EMAC_BIT_MAC_CSR6_PM);
1022
1023	priv->link = 0;
1024	priv->speed = SPEED_UNKNOWN;
1025	priv->duplex = DUPLEX_UNKNOWN;
1026	priv->pause = 0;
1027	priv->mcaddr_list.count = 0;
1028
1029	return 0;
1030}
1031
1032static int owl_emac_enable(struct net_device *netdev, bool start_phy)
1033{
1034	struct owl_emac_priv *priv = netdev_priv(netdev);
1035	int ret;
1036
1037	owl_emac_dma_cmd_stop(priv);
1038	owl_emac_irq_disable(priv);
1039	owl_emac_irq_clear(priv);
1040
1041	owl_emac_ring_prepare_tx(priv);
1042	ret = owl_emac_ring_prepare_rx(priv);
1043	if (ret)
1044		goto err_unprep;
1045
1046	ret = owl_emac_core_sw_reset(priv);
1047	if (ret) {
1048		netdev_err(netdev, "failed to soft reset MAC core: %d\n", ret);
1049		goto err_unprep;
1050	}
1051
1052	owl_emac_set_hw_mac_addr(netdev);
1053	owl_emac_setup_frame_xmit(priv);
1054
1055	netdev_reset_queue(netdev);
1056	napi_enable(&priv->napi);
1057
1058	owl_emac_irq_enable(priv);
1059	owl_emac_dma_cmd_start(priv);
1060
1061	if (start_phy)
1062		phy_start(netdev->phydev);
1063
1064	netif_start_queue(netdev);
1065
1066	return 0;
1067
1068err_unprep:
1069	owl_emac_ring_unprepare_rx(priv);
1070	owl_emac_ring_unprepare_tx(priv);
1071
1072	return ret;
1073}
1074
1075static void owl_emac_disable(struct net_device *netdev, bool stop_phy)
1076{
1077	struct owl_emac_priv *priv = netdev_priv(netdev);
1078
1079	owl_emac_dma_cmd_stop(priv);
1080	owl_emac_irq_disable(priv);
1081
1082	netif_stop_queue(netdev);
1083	napi_disable(&priv->napi);
1084
1085	if (stop_phy)
1086		phy_stop(netdev->phydev);
1087
1088	owl_emac_ring_unprepare_rx(priv);
1089	owl_emac_ring_unprepare_tx(priv);
1090}
1091
1092static int owl_emac_ndo_open(struct net_device *netdev)
1093{
1094	return owl_emac_enable(netdev, true);
1095}
1096
1097static int owl_emac_ndo_stop(struct net_device *netdev)
1098{
1099	owl_emac_disable(netdev, true);
1100
1101	return 0;
1102}
1103
1104static void owl_emac_set_multicast(struct net_device *netdev, int count)
1105{
1106	struct owl_emac_priv *priv = netdev_priv(netdev);
1107	struct netdev_hw_addr *ha;
1108	int index = 0;
1109
1110	if (count <= 0) {
1111		priv->mcaddr_list.count = 0;
1112		return;
1113	}
1114
1115	netdev_for_each_mc_addr(ha, netdev) {
1116		if (!is_multicast_ether_addr(ha->addr))
1117			continue;
1118
1119		WARN_ON(index >= OWL_EMAC_MAX_MULTICAST_ADDRS);
1120		ether_addr_copy(priv->mcaddr_list.addrs[index++], ha->addr);
1121	}
1122
1123	priv->mcaddr_list.count = index;
1124
1125	owl_emac_setup_frame_xmit(priv);
1126}
1127
1128static void owl_emac_ndo_set_rx_mode(struct net_device *netdev)
1129{
1130	struct owl_emac_priv *priv = netdev_priv(netdev);
1131	u32 status, val = 0;
1132	int mcast_count = 0;
1133
1134	if (netdev->flags & IFF_PROMISC) {
1135		val = OWL_EMAC_BIT_MAC_CSR6_PR;
1136	} else if (netdev->flags & IFF_ALLMULTI) {
1137		val = OWL_EMAC_BIT_MAC_CSR6_PM;
1138	} else if (netdev->flags & IFF_MULTICAST) {
1139		mcast_count = netdev_mc_count(netdev);
1140
1141		if (mcast_count > OWL_EMAC_MAX_MULTICAST_ADDRS) {
1142			val = OWL_EMAC_BIT_MAC_CSR6_PM;
1143			mcast_count = 0;
1144		}
1145	}
1146
1147	spin_lock_bh(&priv->lock);
1148
1149	/* Temporarily stop DMA TX & RX. */
1150	status = owl_emac_dma_cmd_stop(priv);
1151
1152	/* Update operation modes. */
1153	owl_emac_reg_update(priv, OWL_EMAC_REG_MAC_CSR6,
1154			    OWL_EMAC_BIT_MAC_CSR6_PR | OWL_EMAC_BIT_MAC_CSR6_PM,
1155			    val);
1156
1157	/* Restore DMA TX & RX status. */
1158	owl_emac_dma_cmd_set(priv, status);
1159
1160	spin_unlock_bh(&priv->lock);
1161
1162	/* Set/reset multicast addr list. */
1163	owl_emac_set_multicast(netdev, mcast_count);
1164}
1165
1166static int owl_emac_ndo_set_mac_addr(struct net_device *netdev, void *addr)
1167{
1168	struct sockaddr *skaddr = addr;
1169
1170	if (!is_valid_ether_addr(skaddr->sa_data))
1171		return -EADDRNOTAVAIL;
1172
1173	if (netif_running(netdev))
1174		return -EBUSY;
1175
1176	eth_hw_addr_set(netdev, skaddr->sa_data);
1177	owl_emac_set_hw_mac_addr(netdev);
1178
1179	return owl_emac_setup_frame_xmit(netdev_priv(netdev));
1180}
1181
1182static int owl_emac_ndo_eth_ioctl(struct net_device *netdev,
1183				  struct ifreq *req, int cmd)
1184{
1185	if (!netif_running(netdev))
1186		return -EINVAL;
1187
1188	return phy_mii_ioctl(netdev->phydev, req, cmd);
1189}
1190
1191static void owl_emac_ndo_tx_timeout(struct net_device *netdev,
1192				    unsigned int txqueue)
1193{
1194	struct owl_emac_priv *priv = netdev_priv(netdev);
1195
1196	schedule_work(&priv->mac_reset_task);
1197}
1198
1199static void owl_emac_reset_task(struct work_struct *work)
1200{
1201	struct owl_emac_priv *priv;
1202
1203	priv = container_of(work, struct owl_emac_priv, mac_reset_task);
1204
1205	netdev_dbg(priv->netdev, "resetting MAC\n");
1206	owl_emac_disable(priv->netdev, false);
1207	owl_emac_enable(priv->netdev, false);
1208}
1209
1210static struct net_device_stats *
1211owl_emac_ndo_get_stats(struct net_device *netdev)
1212{
1213	/* FIXME: If possible, try to get stats from MAC hardware registers
1214	 * instead of tracking them manually in the driver.
1215	 */
1216
1217	return &netdev->stats;
1218}
1219
1220static const struct net_device_ops owl_emac_netdev_ops = {
1221	.ndo_open		= owl_emac_ndo_open,
1222	.ndo_stop		= owl_emac_ndo_stop,
1223	.ndo_start_xmit		= owl_emac_ndo_start_xmit,
1224	.ndo_set_rx_mode	= owl_emac_ndo_set_rx_mode,
1225	.ndo_set_mac_address	= owl_emac_ndo_set_mac_addr,
1226	.ndo_validate_addr	= eth_validate_addr,
1227	.ndo_eth_ioctl		= owl_emac_ndo_eth_ioctl,
1228	.ndo_tx_timeout         = owl_emac_ndo_tx_timeout,
1229	.ndo_get_stats		= owl_emac_ndo_get_stats,
1230};
1231
1232static void owl_emac_ethtool_get_drvinfo(struct net_device *dev,
1233					 struct ethtool_drvinfo *info)
1234{
1235	strscpy(info->driver, OWL_EMAC_DRVNAME, sizeof(info->driver));
1236}
1237
1238static u32 owl_emac_ethtool_get_msglevel(struct net_device *netdev)
1239{
1240	struct owl_emac_priv *priv = netdev_priv(netdev);
1241
1242	return priv->msg_enable;
1243}
1244
1245static void owl_emac_ethtool_set_msglevel(struct net_device *ndev, u32 val)
1246{
1247	struct owl_emac_priv *priv = netdev_priv(ndev);
1248
1249	priv->msg_enable = val;
1250}
1251
1252static const struct ethtool_ops owl_emac_ethtool_ops = {
1253	.get_drvinfo		= owl_emac_ethtool_get_drvinfo,
1254	.get_link		= ethtool_op_get_link,
1255	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1256	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1257	.get_msglevel		= owl_emac_ethtool_get_msglevel,
1258	.set_msglevel		= owl_emac_ethtool_set_msglevel,
1259};
1260
1261static int owl_emac_mdio_wait(struct owl_emac_priv *priv)
1262{
1263	u32 val;
1264
1265	/* Wait while data transfer is in progress. */
1266	return readl_poll_timeout(priv->base + OWL_EMAC_REG_MAC_CSR10,
1267				  val, !(val & OWL_EMAC_BIT_MAC_CSR10_SB),
1268				  OWL_EMAC_POLL_DELAY_USEC,
1269				  OWL_EMAC_MDIO_POLL_TIMEOUT_USEC);
1270}
1271
1272static int owl_emac_mdio_read(struct mii_bus *bus, int addr, int regnum)
1273{
1274	struct owl_emac_priv *priv = bus->priv;
1275	u32 data, tmp;
1276	int ret;
1277
1278	data = OWL_EMAC_BIT_MAC_CSR10_SB;
1279	data |= OWL_EMAC_VAL_MAC_CSR10_OPCODE_RD << OWL_EMAC_OFF_MAC_CSR10_OPCODE;
1280
1281	tmp = addr << OWL_EMAC_OFF_MAC_CSR10_PHYADD;
1282	data |= tmp & OWL_EMAC_MSK_MAC_CSR10_PHYADD;
1283
1284	tmp = regnum << OWL_EMAC_OFF_MAC_CSR10_REGADD;
1285	data |= tmp & OWL_EMAC_MSK_MAC_CSR10_REGADD;
1286
1287	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR10, data);
1288
1289	ret = owl_emac_mdio_wait(priv);
1290	if (ret)
1291		return ret;
1292
1293	data = owl_emac_reg_read(priv, OWL_EMAC_REG_MAC_CSR10);
1294	data &= OWL_EMAC_MSK_MAC_CSR10_DATA;
1295
1296	return data;
1297}
1298
1299static int
1300owl_emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
1301{
1302	struct owl_emac_priv *priv = bus->priv;
1303	u32 data, tmp;
1304
1305	data = OWL_EMAC_BIT_MAC_CSR10_SB;
1306	data |= OWL_EMAC_VAL_MAC_CSR10_OPCODE_WR << OWL_EMAC_OFF_MAC_CSR10_OPCODE;
1307
1308	tmp = addr << OWL_EMAC_OFF_MAC_CSR10_PHYADD;
1309	data |= tmp & OWL_EMAC_MSK_MAC_CSR10_PHYADD;
1310
1311	tmp = regnum << OWL_EMAC_OFF_MAC_CSR10_REGADD;
1312	data |= tmp & OWL_EMAC_MSK_MAC_CSR10_REGADD;
1313
1314	data |= val & OWL_EMAC_MSK_MAC_CSR10_DATA;
1315
1316	owl_emac_reg_write(priv, OWL_EMAC_REG_MAC_CSR10, data);
1317
1318	return owl_emac_mdio_wait(priv);
1319}
1320
1321static int owl_emac_mdio_init(struct net_device *netdev)
1322{
1323	struct owl_emac_priv *priv = netdev_priv(netdev);
1324	struct device *dev = owl_emac_get_dev(priv);
1325	struct device_node *mdio_node;
1326	int ret;
1327
1328	mdio_node = of_get_child_by_name(dev->of_node, "mdio");
1329	if (!mdio_node)
1330		return -ENODEV;
1331
1332	if (!of_device_is_available(mdio_node)) {
1333		ret = -ENODEV;
1334		goto err_put_node;
1335	}
1336
1337	priv->mii = devm_mdiobus_alloc(dev);
1338	if (!priv->mii) {
1339		ret = -ENOMEM;
1340		goto err_put_node;
1341	}
1342
1343	snprintf(priv->mii->id, MII_BUS_ID_SIZE, "%s", dev_name(dev));
1344	priv->mii->name = "owl-emac-mdio";
1345	priv->mii->parent = dev;
1346	priv->mii->read = owl_emac_mdio_read;
1347	priv->mii->write = owl_emac_mdio_write;
1348	priv->mii->phy_mask = ~0; /* Mask out all PHYs from auto probing. */
1349	priv->mii->priv = priv;
1350
1351	ret = devm_of_mdiobus_register(dev, priv->mii, mdio_node);
1352
1353err_put_node:
1354	of_node_put(mdio_node);
1355	return ret;
1356}
1357
1358static int owl_emac_phy_init(struct net_device *netdev)
1359{
1360	struct owl_emac_priv *priv = netdev_priv(netdev);
1361	struct device *dev = owl_emac_get_dev(priv);
1362	struct phy_device *phy;
1363
1364	phy = of_phy_get_and_connect(netdev, dev->of_node,
1365				     owl_emac_adjust_link);
1366	if (!phy)
1367		return -ENODEV;
1368
1369	phy_set_sym_pause(phy, true, true, true);
1370
1371	if (netif_msg_link(priv))
1372		phy_attached_info(phy);
1373
1374	return 0;
1375}
1376
1377static void owl_emac_get_mac_addr(struct net_device *netdev)
1378{
1379	struct device *dev = netdev->dev.parent;
1380	int ret;
1381
1382	ret = platform_get_ethdev_address(dev, netdev);
1383	if (!ret && is_valid_ether_addr(netdev->dev_addr))
1384		return;
1385
1386	eth_hw_addr_random(netdev);
1387	dev_warn(dev, "using random MAC address %pM\n", netdev->dev_addr);
1388}
1389
1390static __maybe_unused int owl_emac_suspend(struct device *dev)
1391{
1392	struct net_device *netdev = dev_get_drvdata(dev);
1393	struct owl_emac_priv *priv = netdev_priv(netdev);
1394
1395	disable_irq(netdev->irq);
1396
1397	if (netif_running(netdev)) {
1398		owl_emac_disable(netdev, true);
1399		netif_device_detach(netdev);
1400	}
1401
1402	clk_bulk_disable_unprepare(OWL_EMAC_NCLKS, priv->clks);
1403
1404	return 0;
1405}
1406
1407static __maybe_unused int owl_emac_resume(struct device *dev)
1408{
1409	struct net_device *netdev = dev_get_drvdata(dev);
1410	struct owl_emac_priv *priv = netdev_priv(netdev);
1411	int ret;
1412
1413	ret = clk_bulk_prepare_enable(OWL_EMAC_NCLKS, priv->clks);
1414	if (ret)
1415		return ret;
1416
1417	if (netif_running(netdev)) {
1418		owl_emac_core_hw_reset(priv);
1419		owl_emac_core_sw_reset(priv);
1420
1421		ret = owl_emac_enable(netdev, true);
1422		if (ret) {
1423			clk_bulk_disable_unprepare(OWL_EMAC_NCLKS, priv->clks);
1424			return ret;
1425		}
1426
1427		netif_device_attach(netdev);
1428	}
1429
1430	enable_irq(netdev->irq);
1431
1432	return 0;
1433}
1434
1435static void owl_emac_clk_disable_unprepare(void *data)
1436{
1437	struct owl_emac_priv *priv = data;
1438
1439	clk_bulk_disable_unprepare(OWL_EMAC_NCLKS, priv->clks);
1440}
1441
1442static int owl_emac_clk_set_rate(struct owl_emac_priv *priv)
1443{
1444	struct device *dev = owl_emac_get_dev(priv);
1445	unsigned long rate;
1446	int ret;
1447
1448	switch (priv->phy_mode) {
1449	case PHY_INTERFACE_MODE_RMII:
1450		rate = 50000000;
1451		break;
1452
1453	case PHY_INTERFACE_MODE_SMII:
1454		rate = 125000000;
1455		break;
1456
1457	default:
1458		dev_err(dev, "unsupported phy interface mode %d\n",
1459			priv->phy_mode);
1460		return -EOPNOTSUPP;
1461	}
1462
1463	ret = clk_set_rate(priv->clks[OWL_EMAC_CLK_RMII].clk, rate);
1464	if (ret)
1465		dev_err(dev, "failed to set RMII clock rate: %d\n", ret);
1466
1467	return ret;
1468}
1469
1470static int owl_emac_probe(struct platform_device *pdev)
1471{
1472	struct device *dev = &pdev->dev;
1473	struct net_device *netdev;
1474	struct owl_emac_priv *priv;
1475	int ret, i;
1476
1477	netdev = devm_alloc_etherdev(dev, sizeof(*priv));
1478	if (!netdev)
1479		return -ENOMEM;
1480
1481	platform_set_drvdata(pdev, netdev);
1482	SET_NETDEV_DEV(netdev, dev);
1483
1484	priv = netdev_priv(netdev);
1485	priv->netdev = netdev;
1486	priv->msg_enable = netif_msg_init(-1, OWL_EMAC_DEFAULT_MSG_ENABLE);
1487
1488	ret = of_get_phy_mode(dev->of_node, &priv->phy_mode);
1489	if (ret) {
1490		dev_err(dev, "failed to get phy mode: %d\n", ret);
1491		return ret;
1492	}
1493
1494	spin_lock_init(&priv->lock);
1495
1496	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
1497	if (ret) {
1498		dev_err(dev, "unsupported DMA mask\n");
1499		return ret;
1500	}
1501
1502	ret = owl_emac_ring_alloc(dev, &priv->rx_ring, OWL_EMAC_RX_RING_SIZE);
1503	if (ret)
1504		return ret;
1505
1506	ret = owl_emac_ring_alloc(dev, &priv->tx_ring, OWL_EMAC_TX_RING_SIZE);
1507	if (ret)
1508		return ret;
1509
1510	priv->base = devm_platform_ioremap_resource(pdev, 0);
1511	if (IS_ERR(priv->base))
1512		return PTR_ERR(priv->base);
1513
1514	netdev->irq = platform_get_irq(pdev, 0);
1515	if (netdev->irq < 0)
1516		return netdev->irq;
1517
1518	ret = devm_request_irq(dev, netdev->irq, owl_emac_handle_irq,
1519			       IRQF_SHARED, netdev->name, netdev);
1520	if (ret) {
1521		dev_err(dev, "failed to request irq: %d\n", netdev->irq);
1522		return ret;
1523	}
1524
1525	for (i = 0; i < OWL_EMAC_NCLKS; i++)
1526		priv->clks[i].id = owl_emac_clk_names[i];
1527
1528	ret = devm_clk_bulk_get(dev, OWL_EMAC_NCLKS, priv->clks);
1529	if (ret)
1530		return ret;
1531
1532	ret = clk_bulk_prepare_enable(OWL_EMAC_NCLKS, priv->clks);
1533	if (ret)
1534		return ret;
1535
1536	ret = devm_add_action_or_reset(dev, owl_emac_clk_disable_unprepare, priv);
1537	if (ret)
1538		return ret;
1539
1540	ret = owl_emac_clk_set_rate(priv);
1541	if (ret)
1542		return ret;
1543
1544	priv->reset = devm_reset_control_get_exclusive(dev, NULL);
1545	if (IS_ERR(priv->reset))
1546		return dev_err_probe(dev, PTR_ERR(priv->reset),
1547				     "failed to get reset control");
1548
1549	owl_emac_get_mac_addr(netdev);
1550
1551	owl_emac_core_hw_reset(priv);
1552	owl_emac_mdio_clock_enable(priv);
1553
1554	ret = owl_emac_mdio_init(netdev);
1555	if (ret) {
1556		dev_err(dev, "failed to initialize MDIO bus\n");
1557		return ret;
1558	}
1559
1560	ret = owl_emac_phy_init(netdev);
1561	if (ret) {
1562		dev_err(dev, "failed to initialize PHY\n");
1563		return ret;
1564	}
1565
1566	INIT_WORK(&priv->mac_reset_task, owl_emac_reset_task);
1567
1568	netdev->min_mtu = OWL_EMAC_MTU_MIN;
1569	netdev->max_mtu = OWL_EMAC_MTU_MAX;
1570	netdev->watchdog_timeo = OWL_EMAC_TX_TIMEOUT;
1571	netdev->netdev_ops = &owl_emac_netdev_ops;
1572	netdev->ethtool_ops = &owl_emac_ethtool_ops;
1573	netif_napi_add(netdev, &priv->napi, owl_emac_poll);
1574
1575	ret = devm_register_netdev(dev, netdev);
1576	if (ret) {
1577		netif_napi_del(&priv->napi);
1578		phy_disconnect(netdev->phydev);
1579		return ret;
1580	}
1581
1582	return 0;
1583}
1584
1585static void owl_emac_remove(struct platform_device *pdev)
1586{
1587	struct owl_emac_priv *priv = platform_get_drvdata(pdev);
1588
1589	netif_napi_del(&priv->napi);
1590	phy_disconnect(priv->netdev->phydev);
1591	cancel_work_sync(&priv->mac_reset_task);
1592}
1593
1594static const struct of_device_id owl_emac_of_match[] = {
1595	{ .compatible = "actions,owl-emac", },
1596	{ }
1597};
1598MODULE_DEVICE_TABLE(of, owl_emac_of_match);
1599
1600static SIMPLE_DEV_PM_OPS(owl_emac_pm_ops,
1601			 owl_emac_suspend, owl_emac_resume);
1602
1603static struct platform_driver owl_emac_driver = {
1604	.driver = {
1605		.name = OWL_EMAC_DRVNAME,
1606		.of_match_table = owl_emac_of_match,
1607		.pm = &owl_emac_pm_ops,
1608	},
1609	.probe = owl_emac_probe,
1610	.remove_new = owl_emac_remove,
1611};
1612module_platform_driver(owl_emac_driver);
1613
1614MODULE_DESCRIPTION("Actions Semi Owl SoCs Ethernet MAC Driver");
1615MODULE_AUTHOR("Actions Semi Inc.");
1616MODULE_AUTHOR("Cristian Ciocaltea <cristian.ciocaltea@gmail.com>");
1617MODULE_LICENSE("GPL");
1618