1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/drivers/net/ethernet/ethoc.c
4 *
5 * Copyright (C) 2007-2008 Avionic Design Development GmbH
6 * Copyright (C) 2008-2009 Avionic Design GmbH
7 *
8 * Written by Thierry Reding <thierry.reding@avionic-design.de>
9 */
10
11#include <linux/dma-mapping.h>
12#include <linux/etherdevice.h>
13#include <linux/clk.h>
14#include <linux/crc32.h>
15#include <linux/interrupt.h>
16#include <linux/io.h>
17#include <linux/mii.h>
18#include <linux/phy.h>
19#include <linux/platform_device.h>
20#include <linux/sched.h>
21#include <linux/slab.h>
22#include <linux/of.h>
23#include <linux/of_net.h>
24#include <linux/module.h>
25#include <net/ethoc.h>
26
27static int buffer_size = 0x8000; /* 32 KBytes */
28module_param(buffer_size, int, 0);
29MODULE_PARM_DESC(buffer_size, "DMA buffer allocation size");
30
31/* register offsets */
32#define	MODER		0x00
33#define	INT_SOURCE	0x04
34#define	INT_MASK	0x08
35#define	IPGT		0x0c
36#define	IPGR1		0x10
37#define	IPGR2		0x14
38#define	PACKETLEN	0x18
39#define	COLLCONF	0x1c
40#define	TX_BD_NUM	0x20
41#define	CTRLMODER	0x24
42#define	MIIMODER	0x28
43#define	MIICOMMAND	0x2c
44#define	MIIADDRESS	0x30
45#define	MIITX_DATA	0x34
46#define	MIIRX_DATA	0x38
47#define	MIISTATUS	0x3c
48#define	MAC_ADDR0	0x40
49#define	MAC_ADDR1	0x44
50#define	ETH_HASH0	0x48
51#define	ETH_HASH1	0x4c
52#define	ETH_TXCTRL	0x50
53#define	ETH_END		0x54
54
55/* mode register */
56#define	MODER_RXEN	(1 <<  0) /* receive enable */
57#define	MODER_TXEN	(1 <<  1) /* transmit enable */
58#define	MODER_NOPRE	(1 <<  2) /* no preamble */
59#define	MODER_BRO	(1 <<  3) /* broadcast address */
60#define	MODER_IAM	(1 <<  4) /* individual address mode */
61#define	MODER_PRO	(1 <<  5) /* promiscuous mode */
62#define	MODER_IFG	(1 <<  6) /* interframe gap for incoming frames */
63#define	MODER_LOOP	(1 <<  7) /* loopback */
64#define	MODER_NBO	(1 <<  8) /* no back-off */
65#define	MODER_EDE	(1 <<  9) /* excess defer enable */
66#define	MODER_FULLD	(1 << 10) /* full duplex */
67#define	MODER_RESET	(1 << 11) /* FIXME: reset (undocumented) */
68#define	MODER_DCRC	(1 << 12) /* delayed CRC enable */
69#define	MODER_CRC	(1 << 13) /* CRC enable */
70#define	MODER_HUGE	(1 << 14) /* huge packets enable */
71#define	MODER_PAD	(1 << 15) /* padding enabled */
72#define	MODER_RSM	(1 << 16) /* receive small packets */
73
74/* interrupt source and mask registers */
75#define	INT_MASK_TXF	(1 << 0) /* transmit frame */
76#define	INT_MASK_TXE	(1 << 1) /* transmit error */
77#define	INT_MASK_RXF	(1 << 2) /* receive frame */
78#define	INT_MASK_RXE	(1 << 3) /* receive error */
79#define	INT_MASK_BUSY	(1 << 4)
80#define	INT_MASK_TXC	(1 << 5) /* transmit control frame */
81#define	INT_MASK_RXC	(1 << 6) /* receive control frame */
82
83#define	INT_MASK_TX	(INT_MASK_TXF | INT_MASK_TXE)
84#define	INT_MASK_RX	(INT_MASK_RXF | INT_MASK_RXE)
85
86#define	INT_MASK_ALL ( \
87		INT_MASK_TXF | INT_MASK_TXE | \
88		INT_MASK_RXF | INT_MASK_RXE | \
89		INT_MASK_TXC | INT_MASK_RXC | \
90		INT_MASK_BUSY \
91	)
92
93/* packet length register */
94#define	PACKETLEN_MIN(min)		(((min) & 0xffff) << 16)
95#define	PACKETLEN_MAX(max)		(((max) & 0xffff) <<  0)
96#define	PACKETLEN_MIN_MAX(min, max)	(PACKETLEN_MIN(min) | \
97					PACKETLEN_MAX(max))
98
99/* transmit buffer number register */
100#define	TX_BD_NUM_VAL(x)	(((x) <= 0x80) ? (x) : 0x80)
101
102/* control module mode register */
103#define	CTRLMODER_PASSALL	(1 << 0) /* pass all receive frames */
104#define	CTRLMODER_RXFLOW	(1 << 1) /* receive control flow */
105#define	CTRLMODER_TXFLOW	(1 << 2) /* transmit control flow */
106
107/* MII mode register */
108#define	MIIMODER_CLKDIV(x)	((x) & 0xfe) /* needs to be an even number */
109#define	MIIMODER_NOPRE		(1 << 8) /* no preamble */
110
111/* MII command register */
112#define	MIICOMMAND_SCAN		(1 << 0) /* scan status */
113#define	MIICOMMAND_READ		(1 << 1) /* read status */
114#define	MIICOMMAND_WRITE	(1 << 2) /* write control data */
115
116/* MII address register */
117#define	MIIADDRESS_FIAD(x)		(((x) & 0x1f) << 0)
118#define	MIIADDRESS_RGAD(x)		(((x) & 0x1f) << 8)
119#define	MIIADDRESS_ADDR(phy, reg)	(MIIADDRESS_FIAD(phy) | \
120					MIIADDRESS_RGAD(reg))
121
122/* MII transmit data register */
123#define	MIITX_DATA_VAL(x)	((x) & 0xffff)
124
125/* MII receive data register */
126#define	MIIRX_DATA_VAL(x)	((x) & 0xffff)
127
128/* MII status register */
129#define	MIISTATUS_LINKFAIL	(1 << 0)
130#define	MIISTATUS_BUSY		(1 << 1)
131#define	MIISTATUS_INVALID	(1 << 2)
132
133/* TX buffer descriptor */
134#define	TX_BD_CS		(1 <<  0) /* carrier sense lost */
135#define	TX_BD_DF		(1 <<  1) /* defer indication */
136#define	TX_BD_LC		(1 <<  2) /* late collision */
137#define	TX_BD_RL		(1 <<  3) /* retransmission limit */
138#define	TX_BD_RETRY_MASK	(0x00f0)
139#define	TX_BD_RETRY(x)		(((x) & 0x00f0) >>  4)
140#define	TX_BD_UR		(1 <<  8) /* transmitter underrun */
141#define	TX_BD_CRC		(1 << 11) /* TX CRC enable */
142#define	TX_BD_PAD		(1 << 12) /* pad enable for short packets */
143#define	TX_BD_WRAP		(1 << 13)
144#define	TX_BD_IRQ		(1 << 14) /* interrupt request enable */
145#define	TX_BD_READY		(1 << 15) /* TX buffer ready */
146#define	TX_BD_LEN(x)		(((x) & 0xffff) << 16)
147#define	TX_BD_LEN_MASK		(0xffff << 16)
148
149#define	TX_BD_STATS		(TX_BD_CS | TX_BD_DF | TX_BD_LC | \
150				TX_BD_RL | TX_BD_RETRY_MASK | TX_BD_UR)
151
152/* RX buffer descriptor */
153#define	RX_BD_LC	(1 <<  0) /* late collision */
154#define	RX_BD_CRC	(1 <<  1) /* RX CRC error */
155#define	RX_BD_SF	(1 <<  2) /* short frame */
156#define	RX_BD_TL	(1 <<  3) /* too long */
157#define	RX_BD_DN	(1 <<  4) /* dribble nibble */
158#define	RX_BD_IS	(1 <<  5) /* invalid symbol */
159#define	RX_BD_OR	(1 <<  6) /* receiver overrun */
160#define	RX_BD_MISS	(1 <<  7)
161#define	RX_BD_CF	(1 <<  8) /* control frame */
162#define	RX_BD_WRAP	(1 << 13)
163#define	RX_BD_IRQ	(1 << 14) /* interrupt request enable */
164#define	RX_BD_EMPTY	(1 << 15)
165#define	RX_BD_LEN(x)	(((x) & 0xffff) << 16)
166
167#define	RX_BD_STATS	(RX_BD_LC | RX_BD_CRC | RX_BD_SF | RX_BD_TL | \
168			RX_BD_DN | RX_BD_IS | RX_BD_OR | RX_BD_MISS)
169
170#define	ETHOC_BUFSIZ		1536
171#define	ETHOC_ZLEN		64
172#define	ETHOC_BD_BASE		0x400
173#define	ETHOC_TIMEOUT		(HZ / 2)
174#define	ETHOC_MII_TIMEOUT	(1 + (HZ / 5))
175
176/**
177 * struct ethoc - driver-private device structure
178 * @iobase:	pointer to I/O memory region
179 * @membase:	pointer to buffer memory region
180 * @big_endian: just big or little (endian)
181 * @num_bd:	number of buffer descriptors
182 * @num_tx:	number of send buffers
183 * @cur_tx:	last send buffer written
184 * @dty_tx:	last buffer actually sent
185 * @num_rx:	number of receive buffers
186 * @cur_rx:	current receive buffer
187 * @vma:        pointer to array of virtual memory addresses for buffers
188 * @netdev:	pointer to network device structure
189 * @napi:	NAPI structure
190 * @msg_enable:	device state flags
191 * @lock:	device lock
192 * @mdio:	MDIO bus for PHY access
193 * @clk:	clock
194 * @phy_id:	address of attached PHY
195 * @old_link:	previous link info
196 * @old_duplex: previous duplex info
197 */
198struct ethoc {
199	void __iomem *iobase;
200	void __iomem *membase;
201	bool big_endian;
202
203	unsigned int num_bd;
204	unsigned int num_tx;
205	unsigned int cur_tx;
206	unsigned int dty_tx;
207
208	unsigned int num_rx;
209	unsigned int cur_rx;
210
211	void **vma;
212
213	struct net_device *netdev;
214	struct napi_struct napi;
215	u32 msg_enable;
216
217	spinlock_t lock;
218
219	struct mii_bus *mdio;
220	struct clk *clk;
221	s8 phy_id;
222
223	int old_link;
224	int old_duplex;
225};
226
227/**
228 * struct ethoc_bd - buffer descriptor
229 * @stat:	buffer statistics
230 * @addr:	physical memory address
231 */
232struct ethoc_bd {
233	u32 stat;
234	u32 addr;
235};
236
237static inline u32 ethoc_read(struct ethoc *dev, loff_t offset)
238{
239	if (dev->big_endian)
240		return ioread32be(dev->iobase + offset);
241	else
242		return ioread32(dev->iobase + offset);
243}
244
245static inline void ethoc_write(struct ethoc *dev, loff_t offset, u32 data)
246{
247	if (dev->big_endian)
248		iowrite32be(data, dev->iobase + offset);
249	else
250		iowrite32(data, dev->iobase + offset);
251}
252
253static inline void ethoc_read_bd(struct ethoc *dev, int index,
254		struct ethoc_bd *bd)
255{
256	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
257	bd->stat = ethoc_read(dev, offset + 0);
258	bd->addr = ethoc_read(dev, offset + 4);
259}
260
261static inline void ethoc_write_bd(struct ethoc *dev, int index,
262		const struct ethoc_bd *bd)
263{
264	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
265	ethoc_write(dev, offset + 0, bd->stat);
266	ethoc_write(dev, offset + 4, bd->addr);
267}
268
269static inline void ethoc_enable_irq(struct ethoc *dev, u32 mask)
270{
271	u32 imask = ethoc_read(dev, INT_MASK);
272	imask |= mask;
273	ethoc_write(dev, INT_MASK, imask);
274}
275
276static inline void ethoc_disable_irq(struct ethoc *dev, u32 mask)
277{
278	u32 imask = ethoc_read(dev, INT_MASK);
279	imask &= ~mask;
280	ethoc_write(dev, INT_MASK, imask);
281}
282
283static inline void ethoc_ack_irq(struct ethoc *dev, u32 mask)
284{
285	ethoc_write(dev, INT_SOURCE, mask);
286}
287
288static inline void ethoc_enable_rx_and_tx(struct ethoc *dev)
289{
290	u32 mode = ethoc_read(dev, MODER);
291	mode |= MODER_RXEN | MODER_TXEN;
292	ethoc_write(dev, MODER, mode);
293}
294
295static inline void ethoc_disable_rx_and_tx(struct ethoc *dev)
296{
297	u32 mode = ethoc_read(dev, MODER);
298	mode &= ~(MODER_RXEN | MODER_TXEN);
299	ethoc_write(dev, MODER, mode);
300}
301
302static int ethoc_init_ring(struct ethoc *dev, unsigned long mem_start)
303{
304	struct ethoc_bd bd;
305	int i;
306	void *vma;
307
308	dev->cur_tx = 0;
309	dev->dty_tx = 0;
310	dev->cur_rx = 0;
311
312	ethoc_write(dev, TX_BD_NUM, dev->num_tx);
313
314	/* setup transmission buffers */
315	bd.addr = mem_start;
316	bd.stat = TX_BD_IRQ | TX_BD_CRC;
317	vma = dev->membase;
318
319	for (i = 0; i < dev->num_tx; i++) {
320		if (i == dev->num_tx - 1)
321			bd.stat |= TX_BD_WRAP;
322
323		ethoc_write_bd(dev, i, &bd);
324		bd.addr += ETHOC_BUFSIZ;
325
326		dev->vma[i] = vma;
327		vma += ETHOC_BUFSIZ;
328	}
329
330	bd.stat = RX_BD_EMPTY | RX_BD_IRQ;
331
332	for (i = 0; i < dev->num_rx; i++) {
333		if (i == dev->num_rx - 1)
334			bd.stat |= RX_BD_WRAP;
335
336		ethoc_write_bd(dev, dev->num_tx + i, &bd);
337		bd.addr += ETHOC_BUFSIZ;
338
339		dev->vma[dev->num_tx + i] = vma;
340		vma += ETHOC_BUFSIZ;
341	}
342
343	return 0;
344}
345
346static int ethoc_reset(struct ethoc *dev)
347{
348	u32 mode;
349
350	/* TODO: reset controller? */
351
352	ethoc_disable_rx_and_tx(dev);
353
354	/* TODO: setup registers */
355
356	/* enable FCS generation and automatic padding */
357	mode = ethoc_read(dev, MODER);
358	mode |= MODER_CRC | MODER_PAD;
359	ethoc_write(dev, MODER, mode);
360
361	/* set full-duplex mode */
362	mode = ethoc_read(dev, MODER);
363	mode |= MODER_FULLD;
364	ethoc_write(dev, MODER, mode);
365	ethoc_write(dev, IPGT, 0x15);
366
367	ethoc_ack_irq(dev, INT_MASK_ALL);
368	ethoc_enable_irq(dev, INT_MASK_ALL);
369	ethoc_enable_rx_and_tx(dev);
370	return 0;
371}
372
373static unsigned int ethoc_update_rx_stats(struct ethoc *dev,
374		struct ethoc_bd *bd)
375{
376	struct net_device *netdev = dev->netdev;
377	unsigned int ret = 0;
378
379	if (bd->stat & RX_BD_TL) {
380		dev_err(&netdev->dev, "RX: frame too long\n");
381		netdev->stats.rx_length_errors++;
382		ret++;
383	}
384
385	if (bd->stat & RX_BD_SF) {
386		dev_err(&netdev->dev, "RX: frame too short\n");
387		netdev->stats.rx_length_errors++;
388		ret++;
389	}
390
391	if (bd->stat & RX_BD_DN) {
392		dev_err(&netdev->dev, "RX: dribble nibble\n");
393		netdev->stats.rx_frame_errors++;
394	}
395
396	if (bd->stat & RX_BD_CRC) {
397		dev_err(&netdev->dev, "RX: wrong CRC\n");
398		netdev->stats.rx_crc_errors++;
399		ret++;
400	}
401
402	if (bd->stat & RX_BD_OR) {
403		dev_err(&netdev->dev, "RX: overrun\n");
404		netdev->stats.rx_over_errors++;
405		ret++;
406	}
407
408	if (bd->stat & RX_BD_MISS)
409		netdev->stats.rx_missed_errors++;
410
411	if (bd->stat & RX_BD_LC) {
412		dev_err(&netdev->dev, "RX: late collision\n");
413		netdev->stats.collisions++;
414		ret++;
415	}
416
417	return ret;
418}
419
420static int ethoc_rx(struct net_device *dev, int limit)
421{
422	struct ethoc *priv = netdev_priv(dev);
423	int count;
424
425	for (count = 0; count < limit; ++count) {
426		unsigned int entry;
427		struct ethoc_bd bd;
428
429		entry = priv->num_tx + priv->cur_rx;
430		ethoc_read_bd(priv, entry, &bd);
431		if (bd.stat & RX_BD_EMPTY) {
432			ethoc_ack_irq(priv, INT_MASK_RX);
433			/* If packet (interrupt) came in between checking
434			 * BD_EMTPY and clearing the interrupt source, then we
435			 * risk missing the packet as the RX interrupt won't
436			 * trigger right away when we reenable it; hence, check
437			 * BD_EMTPY here again to make sure there isn't such a
438			 * packet waiting for us...
439			 */
440			ethoc_read_bd(priv, entry, &bd);
441			if (bd.stat & RX_BD_EMPTY)
442				break;
443		}
444
445		if (ethoc_update_rx_stats(priv, &bd) == 0) {
446			int size = bd.stat >> 16;
447			struct sk_buff *skb;
448
449			size -= 4; /* strip the CRC */
450			skb = netdev_alloc_skb_ip_align(dev, size);
451
452			if (likely(skb)) {
453				void *src = priv->vma[entry];
454				memcpy_fromio(skb_put(skb, size), src, size);
455				skb->protocol = eth_type_trans(skb, dev);
456				dev->stats.rx_packets++;
457				dev->stats.rx_bytes += size;
458				netif_receive_skb(skb);
459			} else {
460				if (net_ratelimit())
461					dev_warn(&dev->dev,
462					    "low on memory - packet dropped\n");
463
464				dev->stats.rx_dropped++;
465				break;
466			}
467		}
468
469		/* clear the buffer descriptor so it can be reused */
470		bd.stat &= ~RX_BD_STATS;
471		bd.stat |=  RX_BD_EMPTY;
472		ethoc_write_bd(priv, entry, &bd);
473		if (++priv->cur_rx == priv->num_rx)
474			priv->cur_rx = 0;
475	}
476
477	return count;
478}
479
480static void ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
481{
482	struct net_device *netdev = dev->netdev;
483
484	if (bd->stat & TX_BD_LC) {
485		dev_err(&netdev->dev, "TX: late collision\n");
486		netdev->stats.tx_window_errors++;
487	}
488
489	if (bd->stat & TX_BD_RL) {
490		dev_err(&netdev->dev, "TX: retransmit limit\n");
491		netdev->stats.tx_aborted_errors++;
492	}
493
494	if (bd->stat & TX_BD_UR) {
495		dev_err(&netdev->dev, "TX: underrun\n");
496		netdev->stats.tx_fifo_errors++;
497	}
498
499	if (bd->stat & TX_BD_CS) {
500		dev_err(&netdev->dev, "TX: carrier sense lost\n");
501		netdev->stats.tx_carrier_errors++;
502	}
503
504	if (bd->stat & TX_BD_STATS)
505		netdev->stats.tx_errors++;
506
507	netdev->stats.collisions += (bd->stat >> 4) & 0xf;
508	netdev->stats.tx_bytes += bd->stat >> 16;
509	netdev->stats.tx_packets++;
510}
511
512static int ethoc_tx(struct net_device *dev, int limit)
513{
514	struct ethoc *priv = netdev_priv(dev);
515	int count;
516	struct ethoc_bd bd;
517
518	for (count = 0; count < limit; ++count) {
519		unsigned int entry;
520
521		entry = priv->dty_tx & (priv->num_tx-1);
522
523		ethoc_read_bd(priv, entry, &bd);
524
525		if (bd.stat & TX_BD_READY || (priv->dty_tx == priv->cur_tx)) {
526			ethoc_ack_irq(priv, INT_MASK_TX);
527			/* If interrupt came in between reading in the BD
528			 * and clearing the interrupt source, then we risk
529			 * missing the event as the TX interrupt won't trigger
530			 * right away when we reenable it; hence, check
531			 * BD_EMPTY here again to make sure there isn't such an
532			 * event pending...
533			 */
534			ethoc_read_bd(priv, entry, &bd);
535			if (bd.stat & TX_BD_READY ||
536			    (priv->dty_tx == priv->cur_tx))
537				break;
538		}
539
540		ethoc_update_tx_stats(priv, &bd);
541		priv->dty_tx++;
542	}
543
544	if ((priv->cur_tx - priv->dty_tx) <= (priv->num_tx / 2))
545		netif_wake_queue(dev);
546
547	return count;
548}
549
550static irqreturn_t ethoc_interrupt(int irq, void *dev_id)
551{
552	struct net_device *dev = dev_id;
553	struct ethoc *priv = netdev_priv(dev);
554	u32 pending;
555	u32 mask;
556
557	/* Figure out what triggered the interrupt...
558	 * The tricky bit here is that the interrupt source bits get
559	 * set in INT_SOURCE for an event regardless of whether that
560	 * event is masked or not.  Thus, in order to figure out what
561	 * triggered the interrupt, we need to remove the sources
562	 * for all events that are currently masked.  This behaviour
563	 * is not particularly well documented but reasonable...
564	 */
565	mask = ethoc_read(priv, INT_MASK);
566	pending = ethoc_read(priv, INT_SOURCE);
567	pending &= mask;
568
569	if (unlikely(pending == 0))
570		return IRQ_NONE;
571
572	ethoc_ack_irq(priv, pending);
573
574	/* We always handle the dropped packet interrupt */
575	if (pending & INT_MASK_BUSY) {
576		dev_dbg(&dev->dev, "packet dropped\n");
577		dev->stats.rx_dropped++;
578	}
579
580	/* Handle receive/transmit event by switching to polling */
581	if (pending & (INT_MASK_TX | INT_MASK_RX)) {
582		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
583		napi_schedule(&priv->napi);
584	}
585
586	return IRQ_HANDLED;
587}
588
589static int ethoc_get_mac_address(struct net_device *dev, void *addr)
590{
591	struct ethoc *priv = netdev_priv(dev);
592	u8 *mac = (u8 *)addr;
593	u32 reg;
594
595	reg = ethoc_read(priv, MAC_ADDR0);
596	mac[2] = (reg >> 24) & 0xff;
597	mac[3] = (reg >> 16) & 0xff;
598	mac[4] = (reg >>  8) & 0xff;
599	mac[5] = (reg >>  0) & 0xff;
600
601	reg = ethoc_read(priv, MAC_ADDR1);
602	mac[0] = (reg >>  8) & 0xff;
603	mac[1] = (reg >>  0) & 0xff;
604
605	return 0;
606}
607
608static int ethoc_poll(struct napi_struct *napi, int budget)
609{
610	struct ethoc *priv = container_of(napi, struct ethoc, napi);
611	int rx_work_done = 0;
612	int tx_work_done = 0;
613
614	rx_work_done = ethoc_rx(priv->netdev, budget);
615	tx_work_done = ethoc_tx(priv->netdev, budget);
616
617	if (rx_work_done < budget && tx_work_done < budget) {
618		napi_complete_done(napi, rx_work_done);
619		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
620	}
621
622	return rx_work_done;
623}
624
625static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
626{
627	struct ethoc *priv = bus->priv;
628	int i;
629
630	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
631	ethoc_write(priv, MIICOMMAND, MIICOMMAND_READ);
632
633	for (i = 0; i < 5; i++) {
634		u32 status = ethoc_read(priv, MIISTATUS);
635		if (!(status & MIISTATUS_BUSY)) {
636			u32 data = ethoc_read(priv, MIIRX_DATA);
637			/* reset MII command register */
638			ethoc_write(priv, MIICOMMAND, 0);
639			return data;
640		}
641		usleep_range(100, 200);
642	}
643
644	return -EBUSY;
645}
646
647static int ethoc_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
648{
649	struct ethoc *priv = bus->priv;
650	int i;
651
652	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
653	ethoc_write(priv, MIITX_DATA, val);
654	ethoc_write(priv, MIICOMMAND, MIICOMMAND_WRITE);
655
656	for (i = 0; i < 5; i++) {
657		u32 stat = ethoc_read(priv, MIISTATUS);
658		if (!(stat & MIISTATUS_BUSY)) {
659			/* reset MII command register */
660			ethoc_write(priv, MIICOMMAND, 0);
661			return 0;
662		}
663		usleep_range(100, 200);
664	}
665
666	return -EBUSY;
667}
668
669static void ethoc_mdio_poll(struct net_device *dev)
670{
671	struct ethoc *priv = netdev_priv(dev);
672	struct phy_device *phydev = dev->phydev;
673	bool changed = false;
674	u32 mode;
675
676	if (priv->old_link != phydev->link) {
677		changed = true;
678		priv->old_link = phydev->link;
679	}
680
681	if (priv->old_duplex != phydev->duplex) {
682		changed = true;
683		priv->old_duplex = phydev->duplex;
684	}
685
686	if (!changed)
687		return;
688
689	mode = ethoc_read(priv, MODER);
690	if (phydev->duplex == DUPLEX_FULL)
691		mode |= MODER_FULLD;
692	else
693		mode &= ~MODER_FULLD;
694	ethoc_write(priv, MODER, mode);
695
696	phy_print_status(phydev);
697}
698
699static int ethoc_mdio_probe(struct net_device *dev)
700{
701	struct ethoc *priv = netdev_priv(dev);
702	struct phy_device *phy;
703	int err;
704
705	if (priv->phy_id != -1)
706		phy = mdiobus_get_phy(priv->mdio, priv->phy_id);
707	else
708		phy = phy_find_first(priv->mdio);
709
710	if (!phy)
711		return dev_err_probe(&dev->dev, -ENXIO, "no PHY found\n");
712
713	priv->old_duplex = -1;
714	priv->old_link = -1;
715
716	err = phy_connect_direct(dev, phy, ethoc_mdio_poll,
717				 PHY_INTERFACE_MODE_GMII);
718	if (err)
719		return dev_err_probe(&dev->dev, err, "could not attach to PHY\n");
720
721	phy_set_max_speed(phy, SPEED_100);
722
723	return 0;
724}
725
726static int ethoc_open(struct net_device *dev)
727{
728	struct ethoc *priv = netdev_priv(dev);
729	int ret;
730
731	ret = request_irq(dev->irq, ethoc_interrupt, IRQF_SHARED,
732			dev->name, dev);
733	if (ret)
734		return ret;
735
736	napi_enable(&priv->napi);
737
738	ethoc_init_ring(priv, dev->mem_start);
739	ethoc_reset(priv);
740
741	if (netif_queue_stopped(dev)) {
742		dev_dbg(&dev->dev, " resuming queue\n");
743		netif_wake_queue(dev);
744	} else {
745		dev_dbg(&dev->dev, " starting queue\n");
746		netif_start_queue(dev);
747	}
748
749	priv->old_link = -1;
750	priv->old_duplex = -1;
751
752	phy_start(dev->phydev);
753
754	if (netif_msg_ifup(priv)) {
755		dev_info(&dev->dev, "I/O: %08lx Memory: %08lx-%08lx\n",
756				dev->base_addr, dev->mem_start, dev->mem_end);
757	}
758
759	return 0;
760}
761
762static int ethoc_stop(struct net_device *dev)
763{
764	struct ethoc *priv = netdev_priv(dev);
765
766	napi_disable(&priv->napi);
767
768	if (dev->phydev)
769		phy_stop(dev->phydev);
770
771	ethoc_disable_rx_and_tx(priv);
772	free_irq(dev->irq, dev);
773
774	if (!netif_queue_stopped(dev))
775		netif_stop_queue(dev);
776
777	return 0;
778}
779
780static int ethoc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
781{
782	struct ethoc *priv = netdev_priv(dev);
783	struct mii_ioctl_data *mdio = if_mii(ifr);
784	struct phy_device *phy = NULL;
785
786	if (!netif_running(dev))
787		return -EINVAL;
788
789	if (cmd != SIOCGMIIPHY) {
790		if (mdio->phy_id >= PHY_MAX_ADDR)
791			return -ERANGE;
792
793		phy = mdiobus_get_phy(priv->mdio, mdio->phy_id);
794		if (!phy)
795			return -ENODEV;
796	} else {
797		phy = dev->phydev;
798	}
799
800	return phy_mii_ioctl(phy, ifr, cmd);
801}
802
803static void ethoc_do_set_mac_address(struct net_device *dev)
804{
805	const unsigned char *mac = dev->dev_addr;
806	struct ethoc *priv = netdev_priv(dev);
807
808	ethoc_write(priv, MAC_ADDR0, (mac[2] << 24) | (mac[3] << 16) |
809				     (mac[4] <<  8) | (mac[5] <<  0));
810	ethoc_write(priv, MAC_ADDR1, (mac[0] <<  8) | (mac[1] <<  0));
811}
812
813static int ethoc_set_mac_address(struct net_device *dev, void *p)
814{
815	const struct sockaddr *addr = p;
816
817	if (!is_valid_ether_addr(addr->sa_data))
818		return -EADDRNOTAVAIL;
819	eth_hw_addr_set(dev, addr->sa_data);
820	ethoc_do_set_mac_address(dev);
821	return 0;
822}
823
824static void ethoc_set_multicast_list(struct net_device *dev)
825{
826	struct ethoc *priv = netdev_priv(dev);
827	u32 mode = ethoc_read(priv, MODER);
828	struct netdev_hw_addr *ha;
829	u32 hash[2] = { 0, 0 };
830
831	/* set loopback mode if requested */
832	if (dev->flags & IFF_LOOPBACK)
833		mode |=  MODER_LOOP;
834	else
835		mode &= ~MODER_LOOP;
836
837	/* receive broadcast frames if requested */
838	if (dev->flags & IFF_BROADCAST)
839		mode &= ~MODER_BRO;
840	else
841		mode |=  MODER_BRO;
842
843	/* enable promiscuous mode if requested */
844	if (dev->flags & IFF_PROMISC)
845		mode |=  MODER_PRO;
846	else
847		mode &= ~MODER_PRO;
848
849	ethoc_write(priv, MODER, mode);
850
851	/* receive multicast frames */
852	if (dev->flags & IFF_ALLMULTI) {
853		hash[0] = 0xffffffff;
854		hash[1] = 0xffffffff;
855	} else {
856		netdev_for_each_mc_addr(ha, dev) {
857			u32 crc = ether_crc(ETH_ALEN, ha->addr);
858			int bit = (crc >> 26) & 0x3f;
859			hash[bit >> 5] |= 1 << (bit & 0x1f);
860		}
861	}
862
863	ethoc_write(priv, ETH_HASH0, hash[0]);
864	ethoc_write(priv, ETH_HASH1, hash[1]);
865}
866
867static int ethoc_change_mtu(struct net_device *dev, int new_mtu)
868{
869	return -ENOSYS;
870}
871
872static void ethoc_tx_timeout(struct net_device *dev, unsigned int txqueue)
873{
874	struct ethoc *priv = netdev_priv(dev);
875	u32 pending = ethoc_read(priv, INT_SOURCE);
876	if (likely(pending))
877		ethoc_interrupt(dev->irq, dev);
878}
879
880static netdev_tx_t ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
881{
882	struct ethoc *priv = netdev_priv(dev);
883	struct ethoc_bd bd;
884	unsigned int entry;
885	void *dest;
886
887	if (skb_put_padto(skb, ETHOC_ZLEN)) {
888		dev->stats.tx_errors++;
889		goto out_no_free;
890	}
891
892	if (unlikely(skb->len > ETHOC_BUFSIZ)) {
893		dev->stats.tx_errors++;
894		goto out;
895	}
896
897	entry = priv->cur_tx % priv->num_tx;
898	spin_lock_irq(&priv->lock);
899	priv->cur_tx++;
900
901	ethoc_read_bd(priv, entry, &bd);
902	if (unlikely(skb->len < ETHOC_ZLEN))
903		bd.stat |=  TX_BD_PAD;
904	else
905		bd.stat &= ~TX_BD_PAD;
906
907	dest = priv->vma[entry];
908	memcpy_toio(dest, skb->data, skb->len);
909
910	bd.stat &= ~(TX_BD_STATS | TX_BD_LEN_MASK);
911	bd.stat |= TX_BD_LEN(skb->len);
912	ethoc_write_bd(priv, entry, &bd);
913
914	bd.stat |= TX_BD_READY;
915	ethoc_write_bd(priv, entry, &bd);
916
917	if (priv->cur_tx == (priv->dty_tx + priv->num_tx)) {
918		dev_dbg(&dev->dev, "stopping queue\n");
919		netif_stop_queue(dev);
920	}
921
922	spin_unlock_irq(&priv->lock);
923	skb_tx_timestamp(skb);
924out:
925	dev_kfree_skb(skb);
926out_no_free:
927	return NETDEV_TX_OK;
928}
929
930static int ethoc_get_regs_len(struct net_device *netdev)
931{
932	return ETH_END;
933}
934
935static void ethoc_get_regs(struct net_device *dev, struct ethtool_regs *regs,
936			   void *p)
937{
938	struct ethoc *priv = netdev_priv(dev);
939	u32 *regs_buff = p;
940	unsigned i;
941
942	regs->version = 0;
943	for (i = 0; i < ETH_END / sizeof(u32); ++i)
944		regs_buff[i] = ethoc_read(priv, i * sizeof(u32));
945}
946
947static void ethoc_get_ringparam(struct net_device *dev,
948				struct ethtool_ringparam *ring,
949				struct kernel_ethtool_ringparam *kernel_ring,
950				struct netlink_ext_ack *extack)
951{
952	struct ethoc *priv = netdev_priv(dev);
953
954	ring->rx_max_pending = priv->num_bd - 1;
955	ring->rx_mini_max_pending = 0;
956	ring->rx_jumbo_max_pending = 0;
957	ring->tx_max_pending = priv->num_bd - 1;
958
959	ring->rx_pending = priv->num_rx;
960	ring->rx_mini_pending = 0;
961	ring->rx_jumbo_pending = 0;
962	ring->tx_pending = priv->num_tx;
963}
964
965static int ethoc_set_ringparam(struct net_device *dev,
966			       struct ethtool_ringparam *ring,
967			       struct kernel_ethtool_ringparam *kernel_ring,
968			       struct netlink_ext_ack *extack)
969{
970	struct ethoc *priv = netdev_priv(dev);
971
972	if (ring->tx_pending < 1 || ring->rx_pending < 1 ||
973	    ring->tx_pending + ring->rx_pending > priv->num_bd)
974		return -EINVAL;
975	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
976		return -EINVAL;
977
978	if (netif_running(dev)) {
979		netif_tx_disable(dev);
980		ethoc_disable_rx_and_tx(priv);
981		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
982		synchronize_irq(dev->irq);
983	}
984
985	priv->num_tx = rounddown_pow_of_two(ring->tx_pending);
986	priv->num_rx = ring->rx_pending;
987	ethoc_init_ring(priv, dev->mem_start);
988
989	if (netif_running(dev)) {
990		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
991		ethoc_enable_rx_and_tx(priv);
992		netif_wake_queue(dev);
993	}
994	return 0;
995}
996
997static const struct ethtool_ops ethoc_ethtool_ops = {
998	.get_regs_len = ethoc_get_regs_len,
999	.get_regs = ethoc_get_regs,
1000	.nway_reset = phy_ethtool_nway_reset,
1001	.get_link = ethtool_op_get_link,
1002	.get_ringparam = ethoc_get_ringparam,
1003	.set_ringparam = ethoc_set_ringparam,
1004	.get_ts_info = ethtool_op_get_ts_info,
1005	.get_link_ksettings = phy_ethtool_get_link_ksettings,
1006	.set_link_ksettings = phy_ethtool_set_link_ksettings,
1007};
1008
1009static const struct net_device_ops ethoc_netdev_ops = {
1010	.ndo_open = ethoc_open,
1011	.ndo_stop = ethoc_stop,
1012	.ndo_eth_ioctl = ethoc_ioctl,
1013	.ndo_set_mac_address = ethoc_set_mac_address,
1014	.ndo_set_rx_mode = ethoc_set_multicast_list,
1015	.ndo_change_mtu = ethoc_change_mtu,
1016	.ndo_tx_timeout = ethoc_tx_timeout,
1017	.ndo_start_xmit = ethoc_start_xmit,
1018};
1019
1020/**
1021 * ethoc_probe - initialize OpenCores ethernet MAC
1022 * @pdev:	platform device
1023 */
1024static int ethoc_probe(struct platform_device *pdev)
1025{
1026	struct net_device *netdev = NULL;
1027	struct resource *res = NULL;
1028	struct resource *mmio = NULL;
1029	struct resource *mem = NULL;
1030	struct ethoc *priv = NULL;
1031	int num_bd;
1032	int ret = 0;
1033	struct ethoc_platform_data *pdata = dev_get_platdata(&pdev->dev);
1034	u32 eth_clkfreq = pdata ? pdata->eth_clkfreq : 0;
1035
1036	/* allocate networking device */
1037	netdev = alloc_etherdev(sizeof(struct ethoc));
1038	if (!netdev) {
1039		ret = -ENOMEM;
1040		goto out;
1041	}
1042
1043	SET_NETDEV_DEV(netdev, &pdev->dev);
1044	platform_set_drvdata(pdev, netdev);
1045
1046	/* obtain I/O memory space */
1047	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1048	if (!res) {
1049		dev_err(&pdev->dev, "cannot obtain I/O memory space\n");
1050		ret = -ENXIO;
1051		goto free;
1052	}
1053
1054	mmio = devm_request_mem_region(&pdev->dev, res->start,
1055			resource_size(res), res->name);
1056	if (!mmio) {
1057		dev_err(&pdev->dev, "cannot request I/O memory space\n");
1058		ret = -ENXIO;
1059		goto free;
1060	}
1061
1062	netdev->base_addr = mmio->start;
1063
1064	/* obtain buffer memory space */
1065	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1066	if (res) {
1067		mem = devm_request_mem_region(&pdev->dev, res->start,
1068			resource_size(res), res->name);
1069		if (!mem) {
1070			dev_err(&pdev->dev, "cannot request memory space\n");
1071			ret = -ENXIO;
1072			goto free;
1073		}
1074
1075		netdev->mem_start = mem->start;
1076		netdev->mem_end   = mem->end;
1077	}
1078
1079
1080	/* obtain device IRQ number */
1081	ret = platform_get_irq(pdev, 0);
1082	if (ret < 0)
1083		goto free;
1084
1085	netdev->irq = ret;
1086
1087	/* setup driver-private data */
1088	priv = netdev_priv(netdev);
1089	priv->netdev = netdev;
1090
1091	priv->iobase = devm_ioremap(&pdev->dev, netdev->base_addr,
1092			resource_size(mmio));
1093	if (!priv->iobase) {
1094		dev_err(&pdev->dev, "cannot remap I/O memory space\n");
1095		ret = -ENXIO;
1096		goto free;
1097	}
1098
1099	if (netdev->mem_end) {
1100		priv->membase = devm_ioremap(&pdev->dev,
1101			netdev->mem_start, resource_size(mem));
1102		if (!priv->membase) {
1103			dev_err(&pdev->dev, "cannot remap memory space\n");
1104			ret = -ENXIO;
1105			goto free;
1106		}
1107	} else {
1108		/* Allocate buffer memory */
1109		priv->membase = dmam_alloc_coherent(&pdev->dev,
1110			buffer_size, (void *)&netdev->mem_start,
1111			GFP_KERNEL);
1112		if (!priv->membase) {
1113			dev_err(&pdev->dev, "cannot allocate %dB buffer\n",
1114				buffer_size);
1115			ret = -ENOMEM;
1116			goto free;
1117		}
1118		netdev->mem_end = netdev->mem_start + buffer_size;
1119	}
1120
1121	priv->big_endian = pdata ? pdata->big_endian :
1122		of_device_is_big_endian(pdev->dev.of_node);
1123
1124	/* calculate the number of TX/RX buffers, maximum 128 supported */
1125	num_bd = min_t(unsigned int,
1126		128, (netdev->mem_end - netdev->mem_start + 1) / ETHOC_BUFSIZ);
1127	if (num_bd < 4) {
1128		ret = -ENODEV;
1129		goto free;
1130	}
1131	priv->num_bd = num_bd;
1132	/* num_tx must be a power of two */
1133	priv->num_tx = rounddown_pow_of_two(num_bd >> 1);
1134	priv->num_rx = num_bd - priv->num_tx;
1135
1136	dev_dbg(&pdev->dev, "ethoc: num_tx: %d num_rx: %d\n",
1137		priv->num_tx, priv->num_rx);
1138
1139	priv->vma = devm_kcalloc(&pdev->dev, num_bd, sizeof(void *),
1140				 GFP_KERNEL);
1141	if (!priv->vma) {
1142		ret = -ENOMEM;
1143		goto free;
1144	}
1145
1146	/* Allow the platform setup code to pass in a MAC address. */
1147	if (pdata) {
1148		eth_hw_addr_set(netdev, pdata->hwaddr);
1149		priv->phy_id = pdata->phy_id;
1150	} else {
1151		of_get_ethdev_address(pdev->dev.of_node, netdev);
1152		priv->phy_id = -1;
1153	}
1154
1155	/* Check that the given MAC address is valid. If it isn't, read the
1156	 * current MAC from the controller.
1157	 */
1158	if (!is_valid_ether_addr(netdev->dev_addr)) {
1159		u8 addr[ETH_ALEN];
1160
1161		ethoc_get_mac_address(netdev, addr);
1162		eth_hw_addr_set(netdev, addr);
1163	}
1164
1165	/* Check the MAC again for validity, if it still isn't choose and
1166	 * program a random one.
1167	 */
1168	if (!is_valid_ether_addr(netdev->dev_addr))
1169		eth_hw_addr_random(netdev);
1170
1171	ethoc_do_set_mac_address(netdev);
1172
1173	/* Allow the platform setup code to adjust MII management bus clock. */
1174	if (!eth_clkfreq) {
1175		struct clk *clk = devm_clk_get(&pdev->dev, NULL);
1176
1177		if (!IS_ERR(clk)) {
1178			priv->clk = clk;
1179			clk_prepare_enable(clk);
1180			eth_clkfreq = clk_get_rate(clk);
1181		}
1182	}
1183	if (eth_clkfreq) {
1184		u32 clkdiv = MIIMODER_CLKDIV(eth_clkfreq / 2500000 + 1);
1185
1186		if (!clkdiv)
1187			clkdiv = 2;
1188		dev_dbg(&pdev->dev, "setting MII clkdiv to %u\n", clkdiv);
1189		ethoc_write(priv, MIIMODER,
1190			    (ethoc_read(priv, MIIMODER) & MIIMODER_NOPRE) |
1191			    clkdiv);
1192	}
1193
1194	/* register MII bus */
1195	priv->mdio = mdiobus_alloc();
1196	if (!priv->mdio) {
1197		ret = -ENOMEM;
1198		goto free2;
1199	}
1200
1201	priv->mdio->name = "ethoc-mdio";
1202	snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "%s-%d",
1203			priv->mdio->name, pdev->id);
1204	priv->mdio->read = ethoc_mdio_read;
1205	priv->mdio->write = ethoc_mdio_write;
1206	priv->mdio->priv = priv;
1207
1208	ret = mdiobus_register(priv->mdio);
1209	if (ret) {
1210		dev_err(&netdev->dev, "failed to register MDIO bus\n");
1211		goto free3;
1212	}
1213
1214	ret = ethoc_mdio_probe(netdev);
1215	if (ret) {
1216		dev_err(&netdev->dev, "failed to probe MDIO bus\n");
1217		goto error;
1218	}
1219
1220	/* setup the net_device structure */
1221	netdev->netdev_ops = &ethoc_netdev_ops;
1222	netdev->watchdog_timeo = ETHOC_TIMEOUT;
1223	netdev->features |= 0;
1224	netdev->ethtool_ops = &ethoc_ethtool_ops;
1225
1226	/* setup NAPI */
1227	netif_napi_add(netdev, &priv->napi, ethoc_poll);
1228
1229	spin_lock_init(&priv->lock);
1230
1231	ret = register_netdev(netdev);
1232	if (ret < 0) {
1233		dev_err(&netdev->dev, "failed to register interface\n");
1234		goto error2;
1235	}
1236
1237	goto out;
1238
1239error2:
1240	netif_napi_del(&priv->napi);
1241error:
1242	mdiobus_unregister(priv->mdio);
1243free3:
1244	mdiobus_free(priv->mdio);
1245free2:
1246	clk_disable_unprepare(priv->clk);
1247free:
1248	free_netdev(netdev);
1249out:
1250	return ret;
1251}
1252
1253/**
1254 * ethoc_remove - shutdown OpenCores ethernet MAC
1255 * @pdev:	platform device
1256 */
1257static void ethoc_remove(struct platform_device *pdev)
1258{
1259	struct net_device *netdev = platform_get_drvdata(pdev);
1260	struct ethoc *priv = netdev_priv(netdev);
1261
1262	if (netdev) {
1263		netif_napi_del(&priv->napi);
1264		phy_disconnect(netdev->phydev);
1265
1266		if (priv->mdio) {
1267			mdiobus_unregister(priv->mdio);
1268			mdiobus_free(priv->mdio);
1269		}
1270		clk_disable_unprepare(priv->clk);
1271		unregister_netdev(netdev);
1272		free_netdev(netdev);
1273	}
1274}
1275
1276#ifdef CONFIG_PM
1277static int ethoc_suspend(struct platform_device *pdev, pm_message_t state)
1278{
1279	return -ENOSYS;
1280}
1281
1282static int ethoc_resume(struct platform_device *pdev)
1283{
1284	return -ENOSYS;
1285}
1286#else
1287# define ethoc_suspend NULL
1288# define ethoc_resume  NULL
1289#endif
1290
1291static const struct of_device_id ethoc_match[] = {
1292	{ .compatible = "opencores,ethoc", },
1293	{},
1294};
1295MODULE_DEVICE_TABLE(of, ethoc_match);
1296
1297static struct platform_driver ethoc_driver = {
1298	.probe   = ethoc_probe,
1299	.remove_new = ethoc_remove,
1300	.suspend = ethoc_suspend,
1301	.resume  = ethoc_resume,
1302	.driver  = {
1303		.name = "ethoc",
1304		.of_match_table = ethoc_match,
1305	},
1306};
1307
1308module_platform_driver(ethoc_driver);
1309
1310MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
1311MODULE_DESCRIPTION("OpenCores Ethernet MAC driver");
1312MODULE_LICENSE("GPL v2");
1313
1314