1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Faraday FTMAC100 10/100 Ethernet
4 *
5 * (C) Copyright 2009-2011 Faraday Technology
6 * Po-Yu Chuang <ratbert@faraday-tech.com>
7 */
8
9#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
10
11#include <linux/dma-mapping.h>
12#include <linux/etherdevice.h>
13#include <linux/ethtool.h>
14#include <linux/if_ether.h>
15#include <linux/if_vlan.h>
16#include <linux/init.h>
17#include <linux/interrupt.h>
18#include <linux/io.h>
19#include <linux/mii.h>
20#include <linux/module.h>
21#include <linux/mod_devicetable.h>
22#include <linux/netdevice.h>
23#include <linux/platform_device.h>
24
25#include "ftmac100.h"
26
27#define DRV_NAME	"ftmac100"
28
29#define RX_QUEUE_ENTRIES	128	/* must be power of 2 */
30#define TX_QUEUE_ENTRIES	16	/* must be power of 2 */
31
32#define RX_BUF_SIZE		2044	/* must be smaller than 0x7ff */
33#define MAX_PKT_SIZE		RX_BUF_SIZE /* multi-segment not supported */
34
35#if MAX_PKT_SIZE > 0x7ff
36#error invalid MAX_PKT_SIZE
37#endif
38
39#if RX_BUF_SIZE > 0x7ff || RX_BUF_SIZE > PAGE_SIZE
40#error invalid RX_BUF_SIZE
41#endif
42
43/******************************************************************************
44 * private data
45 *****************************************************************************/
46struct ftmac100_descs {
47	struct ftmac100_rxdes rxdes[RX_QUEUE_ENTRIES];
48	struct ftmac100_txdes txdes[TX_QUEUE_ENTRIES];
49};
50
51struct ftmac100 {
52	struct resource *res;
53	void __iomem *base;
54	int irq;
55
56	struct ftmac100_descs *descs;
57	dma_addr_t descs_dma_addr;
58
59	unsigned int rx_pointer;
60	unsigned int tx_clean_pointer;
61	unsigned int tx_pointer;
62	unsigned int tx_pending;
63
64	spinlock_t tx_lock;
65
66	struct net_device *netdev;
67	struct device *dev;
68	struct napi_struct napi;
69
70	struct mii_if_info mii;
71};
72
73static int ftmac100_alloc_rx_page(struct ftmac100 *priv,
74				  struct ftmac100_rxdes *rxdes, gfp_t gfp);
75
76/******************************************************************************
77 * internal functions (hardware register access)
78 *****************************************************************************/
79#define INT_MASK_ALL_ENABLED	(FTMAC100_INT_RPKT_FINISH	| \
80				 FTMAC100_INT_NORXBUF		| \
81				 FTMAC100_INT_XPKT_OK		| \
82				 FTMAC100_INT_XPKT_LOST		| \
83				 FTMAC100_INT_RPKT_LOST		| \
84				 FTMAC100_INT_AHB_ERR		| \
85				 FTMAC100_INT_PHYSTS_CHG)
86
87#define INT_MASK_ALL_DISABLED	0
88
89static void ftmac100_enable_all_int(struct ftmac100 *priv)
90{
91	iowrite32(INT_MASK_ALL_ENABLED, priv->base + FTMAC100_OFFSET_IMR);
92}
93
94static void ftmac100_disable_all_int(struct ftmac100 *priv)
95{
96	iowrite32(INT_MASK_ALL_DISABLED, priv->base + FTMAC100_OFFSET_IMR);
97}
98
99static void ftmac100_set_rx_ring_base(struct ftmac100 *priv, dma_addr_t addr)
100{
101	iowrite32(addr, priv->base + FTMAC100_OFFSET_RXR_BADR);
102}
103
104static void ftmac100_set_tx_ring_base(struct ftmac100 *priv, dma_addr_t addr)
105{
106	iowrite32(addr, priv->base + FTMAC100_OFFSET_TXR_BADR);
107}
108
109static void ftmac100_txdma_start_polling(struct ftmac100 *priv)
110{
111	iowrite32(1, priv->base + FTMAC100_OFFSET_TXPD);
112}
113
114static int ftmac100_reset(struct ftmac100 *priv)
115{
116	struct net_device *netdev = priv->netdev;
117	int i;
118
119	/* NOTE: reset clears all registers */
120	iowrite32(FTMAC100_MACCR_SW_RST, priv->base + FTMAC100_OFFSET_MACCR);
121
122	for (i = 0; i < 5; i++) {
123		unsigned int maccr;
124
125		maccr = ioread32(priv->base + FTMAC100_OFFSET_MACCR);
126		if (!(maccr & FTMAC100_MACCR_SW_RST)) {
127			/*
128			 * FTMAC100_MACCR_SW_RST cleared does not indicate
129			 * that hardware reset completed (what the f*ck).
130			 * We still need to wait for a while.
131			 */
132			udelay(500);
133			return 0;
134		}
135
136		udelay(1000);
137	}
138
139	netdev_err(netdev, "software reset failed\n");
140	return -EIO;
141}
142
143static void ftmac100_set_mac(struct ftmac100 *priv, const unsigned char *mac)
144{
145	unsigned int maddr = mac[0] << 8 | mac[1];
146	unsigned int laddr = mac[2] << 24 | mac[3] << 16 | mac[4] << 8 | mac[5];
147
148	iowrite32(maddr, priv->base + FTMAC100_OFFSET_MAC_MADR);
149	iowrite32(laddr, priv->base + FTMAC100_OFFSET_MAC_LADR);
150}
151
152static void ftmac100_setup_mc_ht(struct ftmac100 *priv)
153{
154	struct netdev_hw_addr *ha;
155	u64 maht = 0; /* Multicast Address Hash Table */
156
157	netdev_for_each_mc_addr(ha, priv->netdev) {
158		u32 hash = ether_crc(ETH_ALEN, ha->addr) >> 26;
159
160		maht |= BIT_ULL(hash);
161	}
162
163	iowrite32(lower_32_bits(maht), priv->base + FTMAC100_OFFSET_MAHT0);
164	iowrite32(upper_32_bits(maht), priv->base + FTMAC100_OFFSET_MAHT1);
165}
166
167static void ftmac100_set_rx_bits(struct ftmac100 *priv, unsigned int *maccr)
168{
169	struct net_device *netdev = priv->netdev;
170
171	/* Clear all */
172	*maccr &= ~(FTMAC100_MACCR_RCV_ALL | FTMAC100_MACCR_RX_MULTIPKT |
173		   FTMAC100_MACCR_HT_MULTI_EN);
174
175	/* Set the requested bits */
176	if (netdev->flags & IFF_PROMISC)
177		*maccr |= FTMAC100_MACCR_RCV_ALL;
178	if (netdev->flags & IFF_ALLMULTI)
179		*maccr |= FTMAC100_MACCR_RX_MULTIPKT;
180	else if (netdev_mc_count(netdev)) {
181		*maccr |= FTMAC100_MACCR_HT_MULTI_EN;
182		ftmac100_setup_mc_ht(priv);
183	}
184}
185
186#define MACCR_ENABLE_ALL	(FTMAC100_MACCR_XMT_EN	| \
187				 FTMAC100_MACCR_RCV_EN	| \
188				 FTMAC100_MACCR_XDMA_EN	| \
189				 FTMAC100_MACCR_RDMA_EN	| \
190				 FTMAC100_MACCR_CRC_APD	| \
191				 FTMAC100_MACCR_FULLDUP	| \
192				 FTMAC100_MACCR_RX_RUNT	| \
193				 FTMAC100_MACCR_RX_BROADPKT)
194
195static int ftmac100_start_hw(struct ftmac100 *priv)
196{
197	struct net_device *netdev = priv->netdev;
198	unsigned int maccr = MACCR_ENABLE_ALL;
199
200	if (ftmac100_reset(priv))
201		return -EIO;
202
203	/* setup ring buffer base registers */
204	ftmac100_set_rx_ring_base(priv,
205				  priv->descs_dma_addr +
206				  offsetof(struct ftmac100_descs, rxdes));
207	ftmac100_set_tx_ring_base(priv,
208				  priv->descs_dma_addr +
209				  offsetof(struct ftmac100_descs, txdes));
210
211	iowrite32(FTMAC100_APTC_RXPOLL_CNT(1), priv->base + FTMAC100_OFFSET_APTC);
212
213	ftmac100_set_mac(priv, netdev->dev_addr);
214
215	 /* See ftmac100_change_mtu() */
216	if (netdev->mtu > ETH_DATA_LEN)
217		maccr |= FTMAC100_MACCR_RX_FTL;
218
219	ftmac100_set_rx_bits(priv, &maccr);
220
221	iowrite32(maccr, priv->base + FTMAC100_OFFSET_MACCR);
222	return 0;
223}
224
225static void ftmac100_stop_hw(struct ftmac100 *priv)
226{
227	iowrite32(0, priv->base + FTMAC100_OFFSET_MACCR);
228}
229
230/******************************************************************************
231 * internal functions (receive descriptor)
232 *****************************************************************************/
233static bool ftmac100_rxdes_first_segment(struct ftmac100_rxdes *rxdes)
234{
235	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_FRS);
236}
237
238static bool ftmac100_rxdes_last_segment(struct ftmac100_rxdes *rxdes)
239{
240	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_LRS);
241}
242
243static bool ftmac100_rxdes_owned_by_dma(struct ftmac100_rxdes *rxdes)
244{
245	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RXDMA_OWN);
246}
247
248static void ftmac100_rxdes_set_dma_own(struct ftmac100_rxdes *rxdes)
249{
250	/* clear status bits */
251	rxdes->rxdes0 = cpu_to_le32(FTMAC100_RXDES0_RXDMA_OWN);
252}
253
254static bool ftmac100_rxdes_rx_error(struct ftmac100_rxdes *rxdes)
255{
256	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RX_ERR);
257}
258
259static bool ftmac100_rxdes_crc_error(struct ftmac100_rxdes *rxdes)
260{
261	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_CRC_ERR);
262}
263
264static bool ftmac100_rxdes_runt(struct ftmac100_rxdes *rxdes)
265{
266	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RUNT);
267}
268
269static bool ftmac100_rxdes_odd_nibble(struct ftmac100_rxdes *rxdes)
270{
271	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RX_ODD_NB);
272}
273
274static unsigned int ftmac100_rxdes_frame_length(struct ftmac100_rxdes *rxdes)
275{
276	return le32_to_cpu(rxdes->rxdes0) & FTMAC100_RXDES0_RFL;
277}
278
279static bool ftmac100_rxdes_multicast(struct ftmac100_rxdes *rxdes)
280{
281	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_MULTICAST);
282}
283
284static void ftmac100_rxdes_set_buffer_size(struct ftmac100_rxdes *rxdes,
285					   unsigned int size)
286{
287	rxdes->rxdes1 &= cpu_to_le32(FTMAC100_RXDES1_EDORR);
288	rxdes->rxdes1 |= cpu_to_le32(FTMAC100_RXDES1_RXBUF_SIZE(size));
289}
290
291static void ftmac100_rxdes_set_end_of_ring(struct ftmac100_rxdes *rxdes)
292{
293	rxdes->rxdes1 |= cpu_to_le32(FTMAC100_RXDES1_EDORR);
294}
295
296static void ftmac100_rxdes_set_dma_addr(struct ftmac100_rxdes *rxdes,
297					dma_addr_t addr)
298{
299	rxdes->rxdes2 = cpu_to_le32(addr);
300}
301
302static dma_addr_t ftmac100_rxdes_get_dma_addr(struct ftmac100_rxdes *rxdes)
303{
304	return le32_to_cpu(rxdes->rxdes2);
305}
306
307/*
308 * rxdes3 is not used by hardware. We use it to keep track of page.
309 * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
310 */
311static void ftmac100_rxdes_set_page(struct ftmac100_rxdes *rxdes, struct page *page)
312{
313	rxdes->rxdes3 = (unsigned int)page;
314}
315
316static struct page *ftmac100_rxdes_get_page(struct ftmac100_rxdes *rxdes)
317{
318	return (struct page *)rxdes->rxdes3;
319}
320
321/******************************************************************************
322 * internal functions (receive)
323 *****************************************************************************/
324static int ftmac100_next_rx_pointer(int pointer)
325{
326	return (pointer + 1) & (RX_QUEUE_ENTRIES - 1);
327}
328
329static void ftmac100_rx_pointer_advance(struct ftmac100 *priv)
330{
331	priv->rx_pointer = ftmac100_next_rx_pointer(priv->rx_pointer);
332}
333
334static struct ftmac100_rxdes *ftmac100_current_rxdes(struct ftmac100 *priv)
335{
336	return &priv->descs->rxdes[priv->rx_pointer];
337}
338
339static struct ftmac100_rxdes *
340ftmac100_rx_locate_first_segment(struct ftmac100 *priv)
341{
342	struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
343
344	while (!ftmac100_rxdes_owned_by_dma(rxdes)) {
345		if (ftmac100_rxdes_first_segment(rxdes))
346			return rxdes;
347
348		ftmac100_rxdes_set_dma_own(rxdes);
349		ftmac100_rx_pointer_advance(priv);
350		rxdes = ftmac100_current_rxdes(priv);
351	}
352
353	return NULL;
354}
355
356static bool ftmac100_rx_packet_error(struct ftmac100 *priv,
357				     struct ftmac100_rxdes *rxdes)
358{
359	struct net_device *netdev = priv->netdev;
360	bool error = false;
361
362	if (unlikely(ftmac100_rxdes_rx_error(rxdes))) {
363		if (net_ratelimit())
364			netdev_info(netdev, "rx err\n");
365
366		netdev->stats.rx_errors++;
367		error = true;
368	}
369
370	if (unlikely(ftmac100_rxdes_crc_error(rxdes))) {
371		if (net_ratelimit())
372			netdev_info(netdev, "rx crc err\n");
373
374		netdev->stats.rx_crc_errors++;
375		error = true;
376	}
377
378	if (unlikely(ftmac100_rxdes_runt(rxdes))) {
379		if (net_ratelimit())
380			netdev_info(netdev, "rx runt\n");
381
382		netdev->stats.rx_length_errors++;
383		error = true;
384	} else if (unlikely(ftmac100_rxdes_odd_nibble(rxdes))) {
385		if (net_ratelimit())
386			netdev_info(netdev, "rx odd nibble\n");
387
388		netdev->stats.rx_length_errors++;
389		error = true;
390	}
391	/*
392	 * FTMAC100_RXDES0_FTL is not an error, it just indicates that the
393	 * frame is longer than 1518 octets. Receiving these is possible when
394	 * we told the hardware not to drop them, via FTMAC100_MACCR_RX_FTL.
395	 */
396
397	return error;
398}
399
400static void ftmac100_rx_drop_packet(struct ftmac100 *priv)
401{
402	struct net_device *netdev = priv->netdev;
403	struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
404	bool done = false;
405
406	if (net_ratelimit())
407		netdev_dbg(netdev, "drop packet %p\n", rxdes);
408
409	do {
410		if (ftmac100_rxdes_last_segment(rxdes))
411			done = true;
412
413		ftmac100_rxdes_set_dma_own(rxdes);
414		ftmac100_rx_pointer_advance(priv);
415		rxdes = ftmac100_current_rxdes(priv);
416	} while (!done && !ftmac100_rxdes_owned_by_dma(rxdes));
417
418	netdev->stats.rx_dropped++;
419}
420
421static bool ftmac100_rx_packet(struct ftmac100 *priv, int *processed)
422{
423	struct net_device *netdev = priv->netdev;
424	struct ftmac100_rxdes *rxdes;
425	struct sk_buff *skb;
426	struct page *page;
427	dma_addr_t map;
428	int length;
429	bool ret;
430
431	rxdes = ftmac100_rx_locate_first_segment(priv);
432	if (!rxdes)
433		return false;
434
435	if (unlikely(ftmac100_rx_packet_error(priv, rxdes))) {
436		ftmac100_rx_drop_packet(priv);
437		return true;
438	}
439
440	/* We don't support multi-segment packets for now, so drop them. */
441	ret = ftmac100_rxdes_last_segment(rxdes);
442	if (unlikely(!ret)) {
443		netdev->stats.rx_length_errors++;
444		ftmac100_rx_drop_packet(priv);
445		return true;
446	}
447
448	/* start processing */
449	skb = netdev_alloc_skb_ip_align(netdev, 128);
450	if (unlikely(!skb)) {
451		if (net_ratelimit())
452			netdev_err(netdev, "rx skb alloc failed\n");
453
454		ftmac100_rx_drop_packet(priv);
455		return true;
456	}
457
458	if (unlikely(ftmac100_rxdes_multicast(rxdes)))
459		netdev->stats.multicast++;
460
461	map = ftmac100_rxdes_get_dma_addr(rxdes);
462	dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
463
464	length = ftmac100_rxdes_frame_length(rxdes);
465	page = ftmac100_rxdes_get_page(rxdes);
466	skb_fill_page_desc(skb, 0, page, 0, length);
467	skb->len += length;
468	skb->data_len += length;
469
470	if (length > 128) {
471		skb->truesize += PAGE_SIZE;
472		/* We pull the minimum amount into linear part */
473		__pskb_pull_tail(skb, ETH_HLEN);
474	} else {
475		/* Small frames are copied into linear part to free one page */
476		__pskb_pull_tail(skb, length);
477	}
478	ftmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
479
480	ftmac100_rx_pointer_advance(priv);
481
482	skb->protocol = eth_type_trans(skb, netdev);
483
484	netdev->stats.rx_packets++;
485	netdev->stats.rx_bytes += skb->len;
486
487	/* push packet to protocol stack */
488	netif_receive_skb(skb);
489
490	(*processed)++;
491	return true;
492}
493
494/******************************************************************************
495 * internal functions (transmit descriptor)
496 *****************************************************************************/
497static void ftmac100_txdes_reset(struct ftmac100_txdes *txdes)
498{
499	/* clear all except end of ring bit */
500	txdes->txdes0 = 0;
501	txdes->txdes1 &= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
502	txdes->txdes2 = 0;
503	txdes->txdes3 = 0;
504}
505
506static bool ftmac100_txdes_owned_by_dma(struct ftmac100_txdes *txdes)
507{
508	return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
509}
510
511static void ftmac100_txdes_set_dma_own(struct ftmac100_txdes *txdes)
512{
513	/*
514	 * Make sure dma own bit will not be set before any other
515	 * descriptor fields.
516	 */
517	wmb();
518	txdes->txdes0 |= cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
519}
520
521static bool ftmac100_txdes_excessive_collision(struct ftmac100_txdes *txdes)
522{
523	return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_EXSCOL);
524}
525
526static bool ftmac100_txdes_late_collision(struct ftmac100_txdes *txdes)
527{
528	return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_LATECOL);
529}
530
531static void ftmac100_txdes_set_end_of_ring(struct ftmac100_txdes *txdes)
532{
533	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
534}
535
536static void ftmac100_txdes_set_first_segment(struct ftmac100_txdes *txdes)
537{
538	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_FTS);
539}
540
541static void ftmac100_txdes_set_last_segment(struct ftmac100_txdes *txdes)
542{
543	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_LTS);
544}
545
546static void ftmac100_txdes_set_txint(struct ftmac100_txdes *txdes)
547{
548	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXIC);
549}
550
551static void ftmac100_txdes_set_buffer_size(struct ftmac100_txdes *txdes,
552					   unsigned int len)
553{
554	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXBUF_SIZE(len));
555}
556
557static void ftmac100_txdes_set_dma_addr(struct ftmac100_txdes *txdes,
558					dma_addr_t addr)
559{
560	txdes->txdes2 = cpu_to_le32(addr);
561}
562
563static dma_addr_t ftmac100_txdes_get_dma_addr(struct ftmac100_txdes *txdes)
564{
565	return le32_to_cpu(txdes->txdes2);
566}
567
568/*
569 * txdes3 is not used by hardware. We use it to keep track of socket buffer.
570 * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
571 */
572static void ftmac100_txdes_set_skb(struct ftmac100_txdes *txdes, struct sk_buff *skb)
573{
574	txdes->txdes3 = (unsigned int)skb;
575}
576
577static struct sk_buff *ftmac100_txdes_get_skb(struct ftmac100_txdes *txdes)
578{
579	return (struct sk_buff *)txdes->txdes3;
580}
581
582/******************************************************************************
583 * internal functions (transmit)
584 *****************************************************************************/
585static int ftmac100_next_tx_pointer(int pointer)
586{
587	return (pointer + 1) & (TX_QUEUE_ENTRIES - 1);
588}
589
590static void ftmac100_tx_pointer_advance(struct ftmac100 *priv)
591{
592	priv->tx_pointer = ftmac100_next_tx_pointer(priv->tx_pointer);
593}
594
595static void ftmac100_tx_clean_pointer_advance(struct ftmac100 *priv)
596{
597	priv->tx_clean_pointer = ftmac100_next_tx_pointer(priv->tx_clean_pointer);
598}
599
600static struct ftmac100_txdes *ftmac100_current_txdes(struct ftmac100 *priv)
601{
602	return &priv->descs->txdes[priv->tx_pointer];
603}
604
605static struct ftmac100_txdes *ftmac100_current_clean_txdes(struct ftmac100 *priv)
606{
607	return &priv->descs->txdes[priv->tx_clean_pointer];
608}
609
610static bool ftmac100_tx_complete_packet(struct ftmac100 *priv)
611{
612	struct net_device *netdev = priv->netdev;
613	struct ftmac100_txdes *txdes;
614	struct sk_buff *skb;
615	dma_addr_t map;
616
617	if (priv->tx_pending == 0)
618		return false;
619
620	txdes = ftmac100_current_clean_txdes(priv);
621
622	if (ftmac100_txdes_owned_by_dma(txdes))
623		return false;
624
625	skb = ftmac100_txdes_get_skb(txdes);
626	map = ftmac100_txdes_get_dma_addr(txdes);
627
628	if (unlikely(ftmac100_txdes_excessive_collision(txdes) ||
629		     ftmac100_txdes_late_collision(txdes))) {
630		/*
631		 * packet transmitted to ethernet lost due to late collision
632		 * or excessive collision
633		 */
634		netdev->stats.tx_aborted_errors++;
635	} else {
636		netdev->stats.tx_packets++;
637		netdev->stats.tx_bytes += skb->len;
638	}
639
640	dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
641	dev_kfree_skb(skb);
642
643	ftmac100_txdes_reset(txdes);
644
645	ftmac100_tx_clean_pointer_advance(priv);
646
647	spin_lock(&priv->tx_lock);
648	priv->tx_pending--;
649	spin_unlock(&priv->tx_lock);
650	netif_wake_queue(netdev);
651
652	return true;
653}
654
655static void ftmac100_tx_complete(struct ftmac100 *priv)
656{
657	while (ftmac100_tx_complete_packet(priv))
658		;
659}
660
661static netdev_tx_t ftmac100_xmit(struct ftmac100 *priv, struct sk_buff *skb,
662				 dma_addr_t map)
663{
664	struct net_device *netdev = priv->netdev;
665	struct ftmac100_txdes *txdes;
666	unsigned int len = (skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len;
667
668	txdes = ftmac100_current_txdes(priv);
669	ftmac100_tx_pointer_advance(priv);
670
671	/* setup TX descriptor */
672	ftmac100_txdes_set_skb(txdes, skb);
673	ftmac100_txdes_set_dma_addr(txdes, map);
674
675	ftmac100_txdes_set_first_segment(txdes);
676	ftmac100_txdes_set_last_segment(txdes);
677	ftmac100_txdes_set_txint(txdes);
678	ftmac100_txdes_set_buffer_size(txdes, len);
679
680	spin_lock(&priv->tx_lock);
681	priv->tx_pending++;
682	if (priv->tx_pending == TX_QUEUE_ENTRIES)
683		netif_stop_queue(netdev);
684
685	/* start transmit */
686	ftmac100_txdes_set_dma_own(txdes);
687	spin_unlock(&priv->tx_lock);
688
689	ftmac100_txdma_start_polling(priv);
690	return NETDEV_TX_OK;
691}
692
693/******************************************************************************
694 * internal functions (buffer)
695 *****************************************************************************/
696static int ftmac100_alloc_rx_page(struct ftmac100 *priv,
697				  struct ftmac100_rxdes *rxdes, gfp_t gfp)
698{
699	struct net_device *netdev = priv->netdev;
700	struct page *page;
701	dma_addr_t map;
702
703	page = alloc_page(gfp);
704	if (!page) {
705		if (net_ratelimit())
706			netdev_err(netdev, "failed to allocate rx page\n");
707		return -ENOMEM;
708	}
709
710	map = dma_map_page(priv->dev, page, 0, RX_BUF_SIZE, DMA_FROM_DEVICE);
711	if (unlikely(dma_mapping_error(priv->dev, map))) {
712		if (net_ratelimit())
713			netdev_err(netdev, "failed to map rx page\n");
714		__free_page(page);
715		return -ENOMEM;
716	}
717
718	ftmac100_rxdes_set_page(rxdes, page);
719	ftmac100_rxdes_set_dma_addr(rxdes, map);
720	ftmac100_rxdes_set_buffer_size(rxdes, RX_BUF_SIZE);
721	ftmac100_rxdes_set_dma_own(rxdes);
722	return 0;
723}
724
725static void ftmac100_free_buffers(struct ftmac100 *priv)
726{
727	int i;
728
729	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
730		struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
731		struct page *page = ftmac100_rxdes_get_page(rxdes);
732		dma_addr_t map = ftmac100_rxdes_get_dma_addr(rxdes);
733
734		if (!page)
735			continue;
736
737		dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
738		__free_page(page);
739	}
740
741	for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
742		struct ftmac100_txdes *txdes = &priv->descs->txdes[i];
743		struct sk_buff *skb = ftmac100_txdes_get_skb(txdes);
744		dma_addr_t map = ftmac100_txdes_get_dma_addr(txdes);
745
746		if (!skb)
747			continue;
748
749		dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
750		dev_kfree_skb(skb);
751	}
752
753	dma_free_coherent(priv->dev, sizeof(struct ftmac100_descs),
754			  priv->descs, priv->descs_dma_addr);
755}
756
757static int ftmac100_alloc_buffers(struct ftmac100 *priv)
758{
759	int i;
760
761	priv->descs = dma_alloc_coherent(priv->dev,
762					 sizeof(struct ftmac100_descs),
763					 &priv->descs_dma_addr, GFP_KERNEL);
764	if (!priv->descs)
765		return -ENOMEM;
766
767	/* initialize RX ring */
768	ftmac100_rxdes_set_end_of_ring(&priv->descs->rxdes[RX_QUEUE_ENTRIES - 1]);
769
770	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
771		struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
772
773		if (ftmac100_alloc_rx_page(priv, rxdes, GFP_KERNEL))
774			goto err;
775	}
776
777	/* initialize TX ring */
778	ftmac100_txdes_set_end_of_ring(&priv->descs->txdes[TX_QUEUE_ENTRIES - 1]);
779	return 0;
780
781err:
782	ftmac100_free_buffers(priv);
783	return -ENOMEM;
784}
785
786/******************************************************************************
787 * struct mii_if_info functions
788 *****************************************************************************/
789static int ftmac100_mdio_read(struct net_device *netdev, int phy_id, int reg)
790{
791	struct ftmac100 *priv = netdev_priv(netdev);
792	unsigned int phycr;
793	int i;
794
795	phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
796		FTMAC100_PHYCR_REGAD(reg) |
797		FTMAC100_PHYCR_MIIRD;
798
799	iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
800
801	for (i = 0; i < 10; i++) {
802		phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
803
804		if ((phycr & FTMAC100_PHYCR_MIIRD) == 0)
805			return phycr & FTMAC100_PHYCR_MIIRDATA;
806
807		udelay(100);
808	}
809
810	netdev_err(netdev, "mdio read timed out\n");
811	return 0;
812}
813
814static void ftmac100_mdio_write(struct net_device *netdev, int phy_id, int reg,
815				int data)
816{
817	struct ftmac100 *priv = netdev_priv(netdev);
818	unsigned int phycr;
819	int i;
820
821	phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
822		FTMAC100_PHYCR_REGAD(reg) |
823		FTMAC100_PHYCR_MIIWR;
824
825	data = FTMAC100_PHYWDATA_MIIWDATA(data);
826
827	iowrite32(data, priv->base + FTMAC100_OFFSET_PHYWDATA);
828	iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
829
830	for (i = 0; i < 10; i++) {
831		phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
832
833		if ((phycr & FTMAC100_PHYCR_MIIWR) == 0)
834			return;
835
836		udelay(100);
837	}
838
839	netdev_err(netdev, "mdio write timed out\n");
840}
841
842/******************************************************************************
843 * struct ethtool_ops functions
844 *****************************************************************************/
845static void ftmac100_get_drvinfo(struct net_device *netdev,
846				 struct ethtool_drvinfo *info)
847{
848	strscpy(info->driver, DRV_NAME, sizeof(info->driver));
849	strscpy(info->bus_info, dev_name(&netdev->dev), sizeof(info->bus_info));
850}
851
852static int ftmac100_get_link_ksettings(struct net_device *netdev,
853				       struct ethtool_link_ksettings *cmd)
854{
855	struct ftmac100 *priv = netdev_priv(netdev);
856
857	mii_ethtool_get_link_ksettings(&priv->mii, cmd);
858
859	return 0;
860}
861
862static int ftmac100_set_link_ksettings(struct net_device *netdev,
863				       const struct ethtool_link_ksettings *cmd)
864{
865	struct ftmac100 *priv = netdev_priv(netdev);
866	return mii_ethtool_set_link_ksettings(&priv->mii, cmd);
867}
868
869static int ftmac100_nway_reset(struct net_device *netdev)
870{
871	struct ftmac100 *priv = netdev_priv(netdev);
872	return mii_nway_restart(&priv->mii);
873}
874
875static u32 ftmac100_get_link(struct net_device *netdev)
876{
877	struct ftmac100 *priv = netdev_priv(netdev);
878	return mii_link_ok(&priv->mii);
879}
880
881static const struct ethtool_ops ftmac100_ethtool_ops = {
882	.get_drvinfo		= ftmac100_get_drvinfo,
883	.nway_reset		= ftmac100_nway_reset,
884	.get_link		= ftmac100_get_link,
885	.get_link_ksettings	= ftmac100_get_link_ksettings,
886	.set_link_ksettings	= ftmac100_set_link_ksettings,
887};
888
889/******************************************************************************
890 * interrupt handler
891 *****************************************************************************/
892static irqreturn_t ftmac100_interrupt(int irq, void *dev_id)
893{
894	struct net_device *netdev = dev_id;
895	struct ftmac100 *priv = netdev_priv(netdev);
896
897	/* Disable interrupts for polling */
898	ftmac100_disable_all_int(priv);
899	if (likely(netif_running(netdev)))
900		napi_schedule(&priv->napi);
901
902	return IRQ_HANDLED;
903}
904
905/******************************************************************************
906 * struct napi_struct functions
907 *****************************************************************************/
908static int ftmac100_poll(struct napi_struct *napi, int budget)
909{
910	struct ftmac100 *priv = container_of(napi, struct ftmac100, napi);
911	struct net_device *netdev = priv->netdev;
912	unsigned int status;
913	bool completed = true;
914	int rx = 0;
915
916	status = ioread32(priv->base + FTMAC100_OFFSET_ISR);
917
918	if (status & (FTMAC100_INT_RPKT_FINISH | FTMAC100_INT_NORXBUF)) {
919		/*
920		 * FTMAC100_INT_RPKT_FINISH:
921		 *	RX DMA has received packets into RX buffer successfully
922		 *
923		 * FTMAC100_INT_NORXBUF:
924		 *	RX buffer unavailable
925		 */
926		bool retry;
927
928		do {
929			retry = ftmac100_rx_packet(priv, &rx);
930		} while (retry && rx < budget);
931
932		if (retry && rx == budget)
933			completed = false;
934	}
935
936	if (status & (FTMAC100_INT_XPKT_OK | FTMAC100_INT_XPKT_LOST)) {
937		/*
938		 * FTMAC100_INT_XPKT_OK:
939		 *	packet transmitted to ethernet successfully
940		 *
941		 * FTMAC100_INT_XPKT_LOST:
942		 *	packet transmitted to ethernet lost due to late
943		 *	collision or excessive collision
944		 */
945		ftmac100_tx_complete(priv);
946	}
947
948	if (status & (FTMAC100_INT_NORXBUF | FTMAC100_INT_RPKT_LOST |
949		      FTMAC100_INT_AHB_ERR | FTMAC100_INT_PHYSTS_CHG)) {
950		if (net_ratelimit())
951			netdev_info(netdev, "[ISR] = 0x%x: %s%s%s%s\n", status,
952				    status & FTMAC100_INT_NORXBUF ? "NORXBUF " : "",
953				    status & FTMAC100_INT_RPKT_LOST ? "RPKT_LOST " : "",
954				    status & FTMAC100_INT_AHB_ERR ? "AHB_ERR " : "",
955				    status & FTMAC100_INT_PHYSTS_CHG ? "PHYSTS_CHG" : "");
956
957		if (status & FTMAC100_INT_NORXBUF) {
958			/* RX buffer unavailable */
959			netdev->stats.rx_over_errors++;
960		}
961
962		if (status & FTMAC100_INT_RPKT_LOST) {
963			/* received packet lost due to RX FIFO full */
964			netdev->stats.rx_fifo_errors++;
965		}
966
967		if (status & FTMAC100_INT_PHYSTS_CHG) {
968			/* PHY link status change */
969			mii_check_link(&priv->mii);
970		}
971	}
972
973	if (completed) {
974		/* stop polling */
975		napi_complete(napi);
976		ftmac100_enable_all_int(priv);
977	}
978
979	return rx;
980}
981
982/******************************************************************************
983 * struct net_device_ops functions
984 *****************************************************************************/
985static int ftmac100_open(struct net_device *netdev)
986{
987	struct ftmac100 *priv = netdev_priv(netdev);
988	int err;
989
990	err = ftmac100_alloc_buffers(priv);
991	if (err) {
992		netdev_err(netdev, "failed to allocate buffers\n");
993		goto err_alloc;
994	}
995
996	err = request_irq(priv->irq, ftmac100_interrupt, 0, netdev->name, netdev);
997	if (err) {
998		netdev_err(netdev, "failed to request irq %d\n", priv->irq);
999		goto err_irq;
1000	}
1001
1002	priv->rx_pointer = 0;
1003	priv->tx_clean_pointer = 0;
1004	priv->tx_pointer = 0;
1005	priv->tx_pending = 0;
1006
1007	err = ftmac100_start_hw(priv);
1008	if (err)
1009		goto err_hw;
1010
1011	napi_enable(&priv->napi);
1012	netif_start_queue(netdev);
1013
1014	ftmac100_enable_all_int(priv);
1015
1016	return 0;
1017
1018err_hw:
1019	free_irq(priv->irq, netdev);
1020err_irq:
1021	ftmac100_free_buffers(priv);
1022err_alloc:
1023	return err;
1024}
1025
1026static int ftmac100_stop(struct net_device *netdev)
1027{
1028	struct ftmac100 *priv = netdev_priv(netdev);
1029
1030	ftmac100_disable_all_int(priv);
1031	netif_stop_queue(netdev);
1032	napi_disable(&priv->napi);
1033	ftmac100_stop_hw(priv);
1034	free_irq(priv->irq, netdev);
1035	ftmac100_free_buffers(priv);
1036
1037	return 0;
1038}
1039
1040static netdev_tx_t
1041ftmac100_hard_start_xmit(struct sk_buff *skb, struct net_device *netdev)
1042{
1043	struct ftmac100 *priv = netdev_priv(netdev);
1044	dma_addr_t map;
1045
1046	if (unlikely(skb->len > MAX_PKT_SIZE)) {
1047		if (net_ratelimit())
1048			netdev_dbg(netdev, "tx packet too big\n");
1049
1050		netdev->stats.tx_dropped++;
1051		dev_kfree_skb(skb);
1052		return NETDEV_TX_OK;
1053	}
1054
1055	map = dma_map_single(priv->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
1056	if (unlikely(dma_mapping_error(priv->dev, map))) {
1057		/* drop packet */
1058		if (net_ratelimit())
1059			netdev_err(netdev, "map socket buffer failed\n");
1060
1061		netdev->stats.tx_dropped++;
1062		dev_kfree_skb(skb);
1063		return NETDEV_TX_OK;
1064	}
1065
1066	return ftmac100_xmit(priv, skb, map);
1067}
1068
1069/* optional */
1070static int ftmac100_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1071{
1072	struct ftmac100 *priv = netdev_priv(netdev);
1073	struct mii_ioctl_data *data = if_mii(ifr);
1074
1075	return generic_mii_ioctl(&priv->mii, data, cmd, NULL);
1076}
1077
1078static int ftmac100_change_mtu(struct net_device *netdev, int mtu)
1079{
1080	struct ftmac100 *priv = netdev_priv(netdev);
1081	unsigned int maccr;
1082
1083	maccr = ioread32(priv->base + FTMAC100_OFFSET_MACCR);
1084	if (mtu > ETH_DATA_LEN) {
1085		/* process long packets in the driver */
1086		maccr |= FTMAC100_MACCR_RX_FTL;
1087	} else {
1088		/* Let the controller drop incoming packets greater
1089		 * than 1518 (that is 1500 + 14 Ethernet + 4 FCS).
1090		 */
1091		maccr &= ~FTMAC100_MACCR_RX_FTL;
1092	}
1093	iowrite32(maccr, priv->base + FTMAC100_OFFSET_MACCR);
1094
1095	netdev->mtu = mtu;
1096
1097	return 0;
1098}
1099
1100static void ftmac100_set_rx_mode(struct net_device *netdev)
1101{
1102	struct ftmac100 *priv = netdev_priv(netdev);
1103	unsigned int maccr = ioread32(priv->base + FTMAC100_OFFSET_MACCR);
1104
1105	ftmac100_set_rx_bits(priv, &maccr);
1106	iowrite32(maccr, priv->base + FTMAC100_OFFSET_MACCR);
1107}
1108
1109static const struct net_device_ops ftmac100_netdev_ops = {
1110	.ndo_open		= ftmac100_open,
1111	.ndo_stop		= ftmac100_stop,
1112	.ndo_start_xmit		= ftmac100_hard_start_xmit,
1113	.ndo_set_mac_address	= eth_mac_addr,
1114	.ndo_validate_addr	= eth_validate_addr,
1115	.ndo_eth_ioctl		= ftmac100_do_ioctl,
1116	.ndo_change_mtu		= ftmac100_change_mtu,
1117	.ndo_set_rx_mode	= ftmac100_set_rx_mode,
1118};
1119
1120/******************************************************************************
1121 * struct platform_driver functions
1122 *****************************************************************************/
1123static int ftmac100_probe(struct platform_device *pdev)
1124{
1125	struct resource *res;
1126	int irq;
1127	struct net_device *netdev;
1128	struct ftmac100 *priv;
1129	int err;
1130
1131	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1132	if (!res)
1133		return -ENXIO;
1134
1135	irq = platform_get_irq(pdev, 0);
1136	if (irq < 0)
1137		return irq;
1138
1139	/* setup net_device */
1140	netdev = alloc_etherdev(sizeof(*priv));
1141	if (!netdev) {
1142		err = -ENOMEM;
1143		goto err_alloc_etherdev;
1144	}
1145
1146	SET_NETDEV_DEV(netdev, &pdev->dev);
1147	netdev->ethtool_ops = &ftmac100_ethtool_ops;
1148	netdev->netdev_ops = &ftmac100_netdev_ops;
1149	netdev->max_mtu = MAX_PKT_SIZE - VLAN_ETH_HLEN;
1150
1151	err = platform_get_ethdev_address(&pdev->dev, netdev);
1152	if (err == -EPROBE_DEFER)
1153		goto defer_get_mac;
1154
1155	platform_set_drvdata(pdev, netdev);
1156
1157	/* setup private data */
1158	priv = netdev_priv(netdev);
1159	priv->netdev = netdev;
1160	priv->dev = &pdev->dev;
1161
1162	spin_lock_init(&priv->tx_lock);
1163
1164	/* initialize NAPI */
1165	netif_napi_add(netdev, &priv->napi, ftmac100_poll);
1166
1167	/* map io memory */
1168	priv->res = request_mem_region(res->start, resource_size(res),
1169				       dev_name(&pdev->dev));
1170	if (!priv->res) {
1171		dev_err(&pdev->dev, "Could not reserve memory region\n");
1172		err = -ENOMEM;
1173		goto err_req_mem;
1174	}
1175
1176	priv->base = ioremap(res->start, resource_size(res));
1177	if (!priv->base) {
1178		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1179		err = -EIO;
1180		goto err_ioremap;
1181	}
1182
1183	priv->irq = irq;
1184
1185	/* initialize struct mii_if_info */
1186	priv->mii.phy_id	= 0;
1187	priv->mii.phy_id_mask	= 0x1f;
1188	priv->mii.reg_num_mask	= 0x1f;
1189	priv->mii.dev		= netdev;
1190	priv->mii.mdio_read	= ftmac100_mdio_read;
1191	priv->mii.mdio_write	= ftmac100_mdio_write;
1192
1193	/* register network device */
1194	err = register_netdev(netdev);
1195	if (err) {
1196		dev_err(&pdev->dev, "Failed to register netdev\n");
1197		goto err_register_netdev;
1198	}
1199
1200	netdev_info(netdev, "irq %d, mapped at %p\n", priv->irq, priv->base);
1201
1202	if (!is_valid_ether_addr(netdev->dev_addr)) {
1203		eth_hw_addr_random(netdev);
1204		netdev_info(netdev, "generated random MAC address %pM\n",
1205			    netdev->dev_addr);
1206	}
1207
1208	return 0;
1209
1210err_register_netdev:
1211	iounmap(priv->base);
1212err_ioremap:
1213	release_resource(priv->res);
1214err_req_mem:
1215	netif_napi_del(&priv->napi);
1216defer_get_mac:
1217	free_netdev(netdev);
1218err_alloc_etherdev:
1219	return err;
1220}
1221
1222static void ftmac100_remove(struct platform_device *pdev)
1223{
1224	struct net_device *netdev;
1225	struct ftmac100 *priv;
1226
1227	netdev = platform_get_drvdata(pdev);
1228	priv = netdev_priv(netdev);
1229
1230	unregister_netdev(netdev);
1231
1232	iounmap(priv->base);
1233	release_resource(priv->res);
1234
1235	netif_napi_del(&priv->napi);
1236	free_netdev(netdev);
1237}
1238
1239static const struct of_device_id ftmac100_of_ids[] = {
1240	{ .compatible = "andestech,atmac100" },
1241	{ }
1242};
1243
1244static struct platform_driver ftmac100_driver = {
1245	.probe		= ftmac100_probe,
1246	.remove_new	= ftmac100_remove,
1247	.driver		= {
1248		.name	= DRV_NAME,
1249		.of_match_table = ftmac100_of_ids
1250	},
1251};
1252
1253/******************************************************************************
1254 * initialization / finalization
1255 *****************************************************************************/
1256module_platform_driver(ftmac100_driver);
1257
1258MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
1259MODULE_DESCRIPTION("FTMAC100 driver");
1260MODULE_LICENSE("GPL");
1261MODULE_DEVICE_TABLE(of, ftmac100_of_ids);
1262