1/*
2 * Faraday FTMAC100 10/100 Ethernet
3 *
4 * (C) Copyright 2009-2011 Faraday Technology
5 * Po-Yu Chuang <ratbert@faraday-tech.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21
22#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
23
24#include <linux/dma-mapping.h>
25#include <linux/etherdevice.h>
26#include <linux/ethtool.h>
27#include <linux/init.h>
28#include <linux/interrupt.h>
29#include <linux/io.h>
30#include <linux/mii.h>
31#include <linux/module.h>
32#include <linux/netdevice.h>
33#include <linux/platform_device.h>
34
35#include "ftmac100.h"
36
37#define DRV_NAME	"ftmac100"
38#define DRV_VERSION	"0.2"
39
40#define RX_QUEUE_ENTRIES	128	/* must be power of 2 */
41#define TX_QUEUE_ENTRIES	16	/* must be power of 2 */
42
43#define MAX_PKT_SIZE		1518
44#define RX_BUF_SIZE		2044	/* must be smaller than 0x7ff */
45
46#if MAX_PKT_SIZE > 0x7ff
47#error invalid MAX_PKT_SIZE
48#endif
49
50#if RX_BUF_SIZE > 0x7ff || RX_BUF_SIZE > PAGE_SIZE
51#error invalid RX_BUF_SIZE
52#endif
53
54/******************************************************************************
55 * private data
56 *****************************************************************************/
57struct ftmac100_descs {
58	struct ftmac100_rxdes rxdes[RX_QUEUE_ENTRIES];
59	struct ftmac100_txdes txdes[TX_QUEUE_ENTRIES];
60};
61
62struct ftmac100 {
63	struct resource *res;
64	void __iomem *base;
65	int irq;
66
67	struct ftmac100_descs *descs;
68	dma_addr_t descs_dma_addr;
69
70	unsigned int rx_pointer;
71	unsigned int tx_clean_pointer;
72	unsigned int tx_pointer;
73	unsigned int tx_pending;
74
75	spinlock_t tx_lock;
76
77	struct net_device *netdev;
78	struct device *dev;
79	struct napi_struct napi;
80
81	struct mii_if_info mii;
82};
83
84static int ftmac100_alloc_rx_page(struct ftmac100 *priv,
85				  struct ftmac100_rxdes *rxdes, gfp_t gfp);
86
87/******************************************************************************
88 * internal functions (hardware register access)
89 *****************************************************************************/
90#define INT_MASK_ALL_ENABLED	(FTMAC100_INT_RPKT_FINISH	| \
91				 FTMAC100_INT_NORXBUF		| \
92				 FTMAC100_INT_XPKT_OK		| \
93				 FTMAC100_INT_XPKT_LOST		| \
94				 FTMAC100_INT_RPKT_LOST		| \
95				 FTMAC100_INT_AHB_ERR		| \
96				 FTMAC100_INT_PHYSTS_CHG)
97
98#define INT_MASK_ALL_DISABLED	0
99
100static void ftmac100_enable_all_int(struct ftmac100 *priv)
101{
102	iowrite32(INT_MASK_ALL_ENABLED, priv->base + FTMAC100_OFFSET_IMR);
103}
104
105static void ftmac100_disable_all_int(struct ftmac100 *priv)
106{
107	iowrite32(INT_MASK_ALL_DISABLED, priv->base + FTMAC100_OFFSET_IMR);
108}
109
110static void ftmac100_set_rx_ring_base(struct ftmac100 *priv, dma_addr_t addr)
111{
112	iowrite32(addr, priv->base + FTMAC100_OFFSET_RXR_BADR);
113}
114
115static void ftmac100_set_tx_ring_base(struct ftmac100 *priv, dma_addr_t addr)
116{
117	iowrite32(addr, priv->base + FTMAC100_OFFSET_TXR_BADR);
118}
119
120static void ftmac100_txdma_start_polling(struct ftmac100 *priv)
121{
122	iowrite32(1, priv->base + FTMAC100_OFFSET_TXPD);
123}
124
125static int ftmac100_reset(struct ftmac100 *priv)
126{
127	struct net_device *netdev = priv->netdev;
128	int i;
129
130	/* NOTE: reset clears all registers */
131	iowrite32(FTMAC100_MACCR_SW_RST, priv->base + FTMAC100_OFFSET_MACCR);
132
133	for (i = 0; i < 5; i++) {
134		unsigned int maccr;
135
136		maccr = ioread32(priv->base + FTMAC100_OFFSET_MACCR);
137		if (!(maccr & FTMAC100_MACCR_SW_RST)) {
138			/*
139			 * FTMAC100_MACCR_SW_RST cleared does not indicate
140			 * that hardware reset completed (what the f*ck).
141			 * We still need to wait for a while.
142			 */
143			udelay(500);
144			return 0;
145		}
146
147		udelay(1000);
148	}
149
150	netdev_err(netdev, "software reset failed\n");
151	return -EIO;
152}
153
154static void ftmac100_set_mac(struct ftmac100 *priv, const unsigned char *mac)
155{
156	unsigned int maddr = mac[0] << 8 | mac[1];
157	unsigned int laddr = mac[2] << 24 | mac[3] << 16 | mac[4] << 8 | mac[5];
158
159	iowrite32(maddr, priv->base + FTMAC100_OFFSET_MAC_MADR);
160	iowrite32(laddr, priv->base + FTMAC100_OFFSET_MAC_LADR);
161}
162
163#define MACCR_ENABLE_ALL	(FTMAC100_MACCR_XMT_EN	| \
164				 FTMAC100_MACCR_RCV_EN	| \
165				 FTMAC100_MACCR_XDMA_EN	| \
166				 FTMAC100_MACCR_RDMA_EN	| \
167				 FTMAC100_MACCR_CRC_APD	| \
168				 FTMAC100_MACCR_FULLDUP	| \
169				 FTMAC100_MACCR_RX_RUNT	| \
170				 FTMAC100_MACCR_RX_BROADPKT)
171
172static int ftmac100_start_hw(struct ftmac100 *priv)
173{
174	struct net_device *netdev = priv->netdev;
175
176	if (ftmac100_reset(priv))
177		return -EIO;
178
179	/* setup ring buffer base registers */
180	ftmac100_set_rx_ring_base(priv,
181				  priv->descs_dma_addr +
182				  offsetof(struct ftmac100_descs, rxdes));
183	ftmac100_set_tx_ring_base(priv,
184				  priv->descs_dma_addr +
185				  offsetof(struct ftmac100_descs, txdes));
186
187	iowrite32(FTMAC100_APTC_RXPOLL_CNT(1), priv->base + FTMAC100_OFFSET_APTC);
188
189	ftmac100_set_mac(priv, netdev->dev_addr);
190
191	iowrite32(MACCR_ENABLE_ALL, priv->base + FTMAC100_OFFSET_MACCR);
192	return 0;
193}
194
195static void ftmac100_stop_hw(struct ftmac100 *priv)
196{
197	iowrite32(0, priv->base + FTMAC100_OFFSET_MACCR);
198}
199
200/******************************************************************************
201 * internal functions (receive descriptor)
202 *****************************************************************************/
203static bool ftmac100_rxdes_first_segment(struct ftmac100_rxdes *rxdes)
204{
205	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_FRS);
206}
207
208static bool ftmac100_rxdes_last_segment(struct ftmac100_rxdes *rxdes)
209{
210	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_LRS);
211}
212
213static bool ftmac100_rxdes_owned_by_dma(struct ftmac100_rxdes *rxdes)
214{
215	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RXDMA_OWN);
216}
217
218static void ftmac100_rxdes_set_dma_own(struct ftmac100_rxdes *rxdes)
219{
220	/* clear status bits */
221	rxdes->rxdes0 = cpu_to_le32(FTMAC100_RXDES0_RXDMA_OWN);
222}
223
224static bool ftmac100_rxdes_rx_error(struct ftmac100_rxdes *rxdes)
225{
226	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RX_ERR);
227}
228
229static bool ftmac100_rxdes_crc_error(struct ftmac100_rxdes *rxdes)
230{
231	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_CRC_ERR);
232}
233
234static bool ftmac100_rxdes_frame_too_long(struct ftmac100_rxdes *rxdes)
235{
236	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_FTL);
237}
238
239static bool ftmac100_rxdes_runt(struct ftmac100_rxdes *rxdes)
240{
241	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RUNT);
242}
243
244static bool ftmac100_rxdes_odd_nibble(struct ftmac100_rxdes *rxdes)
245{
246	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_RX_ODD_NB);
247}
248
249static unsigned int ftmac100_rxdes_frame_length(struct ftmac100_rxdes *rxdes)
250{
251	return le32_to_cpu(rxdes->rxdes0) & FTMAC100_RXDES0_RFL;
252}
253
254static bool ftmac100_rxdes_multicast(struct ftmac100_rxdes *rxdes)
255{
256	return rxdes->rxdes0 & cpu_to_le32(FTMAC100_RXDES0_MULTICAST);
257}
258
259static void ftmac100_rxdes_set_buffer_size(struct ftmac100_rxdes *rxdes,
260					   unsigned int size)
261{
262	rxdes->rxdes1 &= cpu_to_le32(FTMAC100_RXDES1_EDORR);
263	rxdes->rxdes1 |= cpu_to_le32(FTMAC100_RXDES1_RXBUF_SIZE(size));
264}
265
266static void ftmac100_rxdes_set_end_of_ring(struct ftmac100_rxdes *rxdes)
267{
268	rxdes->rxdes1 |= cpu_to_le32(FTMAC100_RXDES1_EDORR);
269}
270
271static void ftmac100_rxdes_set_dma_addr(struct ftmac100_rxdes *rxdes,
272					dma_addr_t addr)
273{
274	rxdes->rxdes2 = cpu_to_le32(addr);
275}
276
277static dma_addr_t ftmac100_rxdes_get_dma_addr(struct ftmac100_rxdes *rxdes)
278{
279	return le32_to_cpu(rxdes->rxdes2);
280}
281
282/*
283 * rxdes3 is not used by hardware. We use it to keep track of page.
284 * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
285 */
286static void ftmac100_rxdes_set_page(struct ftmac100_rxdes *rxdes, struct page *page)
287{
288	rxdes->rxdes3 = (unsigned int)page;
289}
290
291static struct page *ftmac100_rxdes_get_page(struct ftmac100_rxdes *rxdes)
292{
293	return (struct page *)rxdes->rxdes3;
294}
295
296/******************************************************************************
297 * internal functions (receive)
298 *****************************************************************************/
299static int ftmac100_next_rx_pointer(int pointer)
300{
301	return (pointer + 1) & (RX_QUEUE_ENTRIES - 1);
302}
303
304static void ftmac100_rx_pointer_advance(struct ftmac100 *priv)
305{
306	priv->rx_pointer = ftmac100_next_rx_pointer(priv->rx_pointer);
307}
308
309static struct ftmac100_rxdes *ftmac100_current_rxdes(struct ftmac100 *priv)
310{
311	return &priv->descs->rxdes[priv->rx_pointer];
312}
313
314static struct ftmac100_rxdes *
315ftmac100_rx_locate_first_segment(struct ftmac100 *priv)
316{
317	struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
318
319	while (!ftmac100_rxdes_owned_by_dma(rxdes)) {
320		if (ftmac100_rxdes_first_segment(rxdes))
321			return rxdes;
322
323		ftmac100_rxdes_set_dma_own(rxdes);
324		ftmac100_rx_pointer_advance(priv);
325		rxdes = ftmac100_current_rxdes(priv);
326	}
327
328	return NULL;
329}
330
331static bool ftmac100_rx_packet_error(struct ftmac100 *priv,
332				     struct ftmac100_rxdes *rxdes)
333{
334	struct net_device *netdev = priv->netdev;
335	bool error = false;
336
337	if (unlikely(ftmac100_rxdes_rx_error(rxdes))) {
338		if (net_ratelimit())
339			netdev_info(netdev, "rx err\n");
340
341		netdev->stats.rx_errors++;
342		error = true;
343	}
344
345	if (unlikely(ftmac100_rxdes_crc_error(rxdes))) {
346		if (net_ratelimit())
347			netdev_info(netdev, "rx crc err\n");
348
349		netdev->stats.rx_crc_errors++;
350		error = true;
351	}
352
353	if (unlikely(ftmac100_rxdes_frame_too_long(rxdes))) {
354		if (net_ratelimit())
355			netdev_info(netdev, "rx frame too long\n");
356
357		netdev->stats.rx_length_errors++;
358		error = true;
359	} else if (unlikely(ftmac100_rxdes_runt(rxdes))) {
360		if (net_ratelimit())
361			netdev_info(netdev, "rx runt\n");
362
363		netdev->stats.rx_length_errors++;
364		error = true;
365	} else if (unlikely(ftmac100_rxdes_odd_nibble(rxdes))) {
366		if (net_ratelimit())
367			netdev_info(netdev, "rx odd nibble\n");
368
369		netdev->stats.rx_length_errors++;
370		error = true;
371	}
372
373	return error;
374}
375
376static void ftmac100_rx_drop_packet(struct ftmac100 *priv)
377{
378	struct net_device *netdev = priv->netdev;
379	struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
380	bool done = false;
381
382	if (net_ratelimit())
383		netdev_dbg(netdev, "drop packet %p\n", rxdes);
384
385	do {
386		if (ftmac100_rxdes_last_segment(rxdes))
387			done = true;
388
389		ftmac100_rxdes_set_dma_own(rxdes);
390		ftmac100_rx_pointer_advance(priv);
391		rxdes = ftmac100_current_rxdes(priv);
392	} while (!done && !ftmac100_rxdes_owned_by_dma(rxdes));
393
394	netdev->stats.rx_dropped++;
395}
396
397static bool ftmac100_rx_packet(struct ftmac100 *priv, int *processed)
398{
399	struct net_device *netdev = priv->netdev;
400	struct ftmac100_rxdes *rxdes;
401	struct sk_buff *skb;
402	struct page *page;
403	dma_addr_t map;
404	int length;
405
406	rxdes = ftmac100_rx_locate_first_segment(priv);
407	if (!rxdes)
408		return false;
409
410	if (unlikely(ftmac100_rx_packet_error(priv, rxdes))) {
411		ftmac100_rx_drop_packet(priv);
412		return true;
413	}
414
415	/*
416	 * It is impossible to get multi-segment packets
417	 * because we always provide big enough receive buffers.
418	 */
419	if (unlikely(!ftmac100_rxdes_last_segment(rxdes)))
420		BUG();
421
422	/* start processing */
423	skb = netdev_alloc_skb_ip_align(netdev, 128);
424	if (unlikely(!skb)) {
425		if (net_ratelimit())
426			netdev_err(netdev, "rx skb alloc failed\n");
427
428		ftmac100_rx_drop_packet(priv);
429		return true;
430	}
431
432	if (unlikely(ftmac100_rxdes_multicast(rxdes)))
433		netdev->stats.multicast++;
434
435	map = ftmac100_rxdes_get_dma_addr(rxdes);
436	dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
437
438	length = ftmac100_rxdes_frame_length(rxdes);
439	page = ftmac100_rxdes_get_page(rxdes);
440	skb_fill_page_desc(skb, 0, page, 0, length);
441	skb->len += length;
442	skb->data_len += length;
443
444	if (length > 128) {
445		skb->truesize += PAGE_SIZE;
446		/* We pull the minimum amount into linear part */
447		__pskb_pull_tail(skb, ETH_HLEN);
448	} else {
449		/* Small frames are copied into linear part to free one page */
450		__pskb_pull_tail(skb, length);
451	}
452	ftmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
453
454	ftmac100_rx_pointer_advance(priv);
455
456	skb->protocol = eth_type_trans(skb, netdev);
457
458	netdev->stats.rx_packets++;
459	netdev->stats.rx_bytes += skb->len;
460
461	/* push packet to protocol stack */
462	netif_receive_skb(skb);
463
464	(*processed)++;
465	return true;
466}
467
468/******************************************************************************
469 * internal functions (transmit descriptor)
470 *****************************************************************************/
471static void ftmac100_txdes_reset(struct ftmac100_txdes *txdes)
472{
473	/* clear all except end of ring bit */
474	txdes->txdes0 = 0;
475	txdes->txdes1 &= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
476	txdes->txdes2 = 0;
477	txdes->txdes3 = 0;
478}
479
480static bool ftmac100_txdes_owned_by_dma(struct ftmac100_txdes *txdes)
481{
482	return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
483}
484
485static void ftmac100_txdes_set_dma_own(struct ftmac100_txdes *txdes)
486{
487	/*
488	 * Make sure dma own bit will not be set before any other
489	 * descriptor fields.
490	 */
491	wmb();
492	txdes->txdes0 |= cpu_to_le32(FTMAC100_TXDES0_TXDMA_OWN);
493}
494
495static bool ftmac100_txdes_excessive_collision(struct ftmac100_txdes *txdes)
496{
497	return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_EXSCOL);
498}
499
500static bool ftmac100_txdes_late_collision(struct ftmac100_txdes *txdes)
501{
502	return txdes->txdes0 & cpu_to_le32(FTMAC100_TXDES0_TXPKT_LATECOL);
503}
504
505static void ftmac100_txdes_set_end_of_ring(struct ftmac100_txdes *txdes)
506{
507	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_EDOTR);
508}
509
510static void ftmac100_txdes_set_first_segment(struct ftmac100_txdes *txdes)
511{
512	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_FTS);
513}
514
515static void ftmac100_txdes_set_last_segment(struct ftmac100_txdes *txdes)
516{
517	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_LTS);
518}
519
520static void ftmac100_txdes_set_txint(struct ftmac100_txdes *txdes)
521{
522	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXIC);
523}
524
525static void ftmac100_txdes_set_buffer_size(struct ftmac100_txdes *txdes,
526					   unsigned int len)
527{
528	txdes->txdes1 |= cpu_to_le32(FTMAC100_TXDES1_TXBUF_SIZE(len));
529}
530
531static void ftmac100_txdes_set_dma_addr(struct ftmac100_txdes *txdes,
532					dma_addr_t addr)
533{
534	txdes->txdes2 = cpu_to_le32(addr);
535}
536
537static dma_addr_t ftmac100_txdes_get_dma_addr(struct ftmac100_txdes *txdes)
538{
539	return le32_to_cpu(txdes->txdes2);
540}
541
542/*
543 * txdes3 is not used by hardware. We use it to keep track of socket buffer.
544 * Since hardware does not touch it, we can skip cpu_to_le32()/le32_to_cpu().
545 */
546static void ftmac100_txdes_set_skb(struct ftmac100_txdes *txdes, struct sk_buff *skb)
547{
548	txdes->txdes3 = (unsigned int)skb;
549}
550
551static struct sk_buff *ftmac100_txdes_get_skb(struct ftmac100_txdes *txdes)
552{
553	return (struct sk_buff *)txdes->txdes3;
554}
555
556/******************************************************************************
557 * internal functions (transmit)
558 *****************************************************************************/
559static int ftmac100_next_tx_pointer(int pointer)
560{
561	return (pointer + 1) & (TX_QUEUE_ENTRIES - 1);
562}
563
564static void ftmac100_tx_pointer_advance(struct ftmac100 *priv)
565{
566	priv->tx_pointer = ftmac100_next_tx_pointer(priv->tx_pointer);
567}
568
569static void ftmac100_tx_clean_pointer_advance(struct ftmac100 *priv)
570{
571	priv->tx_clean_pointer = ftmac100_next_tx_pointer(priv->tx_clean_pointer);
572}
573
574static struct ftmac100_txdes *ftmac100_current_txdes(struct ftmac100 *priv)
575{
576	return &priv->descs->txdes[priv->tx_pointer];
577}
578
579static struct ftmac100_txdes *ftmac100_current_clean_txdes(struct ftmac100 *priv)
580{
581	return &priv->descs->txdes[priv->tx_clean_pointer];
582}
583
584static bool ftmac100_tx_complete_packet(struct ftmac100 *priv)
585{
586	struct net_device *netdev = priv->netdev;
587	struct ftmac100_txdes *txdes;
588	struct sk_buff *skb;
589	dma_addr_t map;
590
591	if (priv->tx_pending == 0)
592		return false;
593
594	txdes = ftmac100_current_clean_txdes(priv);
595
596	if (ftmac100_txdes_owned_by_dma(txdes))
597		return false;
598
599	skb = ftmac100_txdes_get_skb(txdes);
600	map = ftmac100_txdes_get_dma_addr(txdes);
601
602	if (unlikely(ftmac100_txdes_excessive_collision(txdes) ||
603		     ftmac100_txdes_late_collision(txdes))) {
604		/*
605		 * packet transmitted to ethernet lost due to late collision
606		 * or excessive collision
607		 */
608		netdev->stats.tx_aborted_errors++;
609	} else {
610		netdev->stats.tx_packets++;
611		netdev->stats.tx_bytes += skb->len;
612	}
613
614	dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
615	dev_kfree_skb(skb);
616
617	ftmac100_txdes_reset(txdes);
618
619	ftmac100_tx_clean_pointer_advance(priv);
620
621	spin_lock(&priv->tx_lock);
622	priv->tx_pending--;
623	spin_unlock(&priv->tx_lock);
624	netif_wake_queue(netdev);
625
626	return true;
627}
628
629static void ftmac100_tx_complete(struct ftmac100 *priv)
630{
631	while (ftmac100_tx_complete_packet(priv))
632		;
633}
634
635static int ftmac100_xmit(struct ftmac100 *priv, struct sk_buff *skb,
636			 dma_addr_t map)
637{
638	struct net_device *netdev = priv->netdev;
639	struct ftmac100_txdes *txdes;
640	unsigned int len = (skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len;
641
642	txdes = ftmac100_current_txdes(priv);
643	ftmac100_tx_pointer_advance(priv);
644
645	/* setup TX descriptor */
646	ftmac100_txdes_set_skb(txdes, skb);
647	ftmac100_txdes_set_dma_addr(txdes, map);
648
649	ftmac100_txdes_set_first_segment(txdes);
650	ftmac100_txdes_set_last_segment(txdes);
651	ftmac100_txdes_set_txint(txdes);
652	ftmac100_txdes_set_buffer_size(txdes, len);
653
654	spin_lock(&priv->tx_lock);
655	priv->tx_pending++;
656	if (priv->tx_pending == TX_QUEUE_ENTRIES)
657		netif_stop_queue(netdev);
658
659	/* start transmit */
660	ftmac100_txdes_set_dma_own(txdes);
661	spin_unlock(&priv->tx_lock);
662
663	ftmac100_txdma_start_polling(priv);
664	return NETDEV_TX_OK;
665}
666
667/******************************************************************************
668 * internal functions (buffer)
669 *****************************************************************************/
670static int ftmac100_alloc_rx_page(struct ftmac100 *priv,
671				  struct ftmac100_rxdes *rxdes, gfp_t gfp)
672{
673	struct net_device *netdev = priv->netdev;
674	struct page *page;
675	dma_addr_t map;
676
677	page = alloc_page(gfp);
678	if (!page) {
679		if (net_ratelimit())
680			netdev_err(netdev, "failed to allocate rx page\n");
681		return -ENOMEM;
682	}
683
684	map = dma_map_page(priv->dev, page, 0, RX_BUF_SIZE, DMA_FROM_DEVICE);
685	if (unlikely(dma_mapping_error(priv->dev, map))) {
686		if (net_ratelimit())
687			netdev_err(netdev, "failed to map rx page\n");
688		__free_page(page);
689		return -ENOMEM;
690	}
691
692	ftmac100_rxdes_set_page(rxdes, page);
693	ftmac100_rxdes_set_dma_addr(rxdes, map);
694	ftmac100_rxdes_set_buffer_size(rxdes, RX_BUF_SIZE);
695	ftmac100_rxdes_set_dma_own(rxdes);
696	return 0;
697}
698
699static void ftmac100_free_buffers(struct ftmac100 *priv)
700{
701	int i;
702
703	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
704		struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
705		struct page *page = ftmac100_rxdes_get_page(rxdes);
706		dma_addr_t map = ftmac100_rxdes_get_dma_addr(rxdes);
707
708		if (!page)
709			continue;
710
711		dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
712		__free_page(page);
713	}
714
715	for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
716		struct ftmac100_txdes *txdes = &priv->descs->txdes[i];
717		struct sk_buff *skb = ftmac100_txdes_get_skb(txdes);
718		dma_addr_t map = ftmac100_txdes_get_dma_addr(txdes);
719
720		if (!skb)
721			continue;
722
723		dma_unmap_single(priv->dev, map, skb_headlen(skb), DMA_TO_DEVICE);
724		dev_kfree_skb(skb);
725	}
726
727	dma_free_coherent(priv->dev, sizeof(struct ftmac100_descs),
728			  priv->descs, priv->descs_dma_addr);
729}
730
731static int ftmac100_alloc_buffers(struct ftmac100 *priv)
732{
733	int i;
734
735	priv->descs = dma_zalloc_coherent(priv->dev,
736					  sizeof(struct ftmac100_descs),
737					  &priv->descs_dma_addr,
738					  GFP_KERNEL);
739	if (!priv->descs)
740		return -ENOMEM;
741
742	/* initialize RX ring */
743	ftmac100_rxdes_set_end_of_ring(&priv->descs->rxdes[RX_QUEUE_ENTRIES - 1]);
744
745	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
746		struct ftmac100_rxdes *rxdes = &priv->descs->rxdes[i];
747
748		if (ftmac100_alloc_rx_page(priv, rxdes, GFP_KERNEL))
749			goto err;
750	}
751
752	/* initialize TX ring */
753	ftmac100_txdes_set_end_of_ring(&priv->descs->txdes[TX_QUEUE_ENTRIES - 1]);
754	return 0;
755
756err:
757	ftmac100_free_buffers(priv);
758	return -ENOMEM;
759}
760
761/******************************************************************************
762 * struct mii_if_info functions
763 *****************************************************************************/
764static int ftmac100_mdio_read(struct net_device *netdev, int phy_id, int reg)
765{
766	struct ftmac100 *priv = netdev_priv(netdev);
767	unsigned int phycr;
768	int i;
769
770	phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
771		FTMAC100_PHYCR_REGAD(reg) |
772		FTMAC100_PHYCR_MIIRD;
773
774	iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
775
776	for (i = 0; i < 10; i++) {
777		phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
778
779		if ((phycr & FTMAC100_PHYCR_MIIRD) == 0)
780			return phycr & FTMAC100_PHYCR_MIIRDATA;
781
782		udelay(100);
783	}
784
785	netdev_err(netdev, "mdio read timed out\n");
786	return 0;
787}
788
789static void ftmac100_mdio_write(struct net_device *netdev, int phy_id, int reg,
790				int data)
791{
792	struct ftmac100 *priv = netdev_priv(netdev);
793	unsigned int phycr;
794	int i;
795
796	phycr = FTMAC100_PHYCR_PHYAD(phy_id) |
797		FTMAC100_PHYCR_REGAD(reg) |
798		FTMAC100_PHYCR_MIIWR;
799
800	data = FTMAC100_PHYWDATA_MIIWDATA(data);
801
802	iowrite32(data, priv->base + FTMAC100_OFFSET_PHYWDATA);
803	iowrite32(phycr, priv->base + FTMAC100_OFFSET_PHYCR);
804
805	for (i = 0; i < 10; i++) {
806		phycr = ioread32(priv->base + FTMAC100_OFFSET_PHYCR);
807
808		if ((phycr & FTMAC100_PHYCR_MIIWR) == 0)
809			return;
810
811		udelay(100);
812	}
813
814	netdev_err(netdev, "mdio write timed out\n");
815}
816
817/******************************************************************************
818 * struct ethtool_ops functions
819 *****************************************************************************/
820static void ftmac100_get_drvinfo(struct net_device *netdev,
821				 struct ethtool_drvinfo *info)
822{
823	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
824	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
825	strlcpy(info->bus_info, dev_name(&netdev->dev), sizeof(info->bus_info));
826}
827
828static int ftmac100_get_settings(struct net_device *netdev, struct ethtool_cmd *cmd)
829{
830	struct ftmac100 *priv = netdev_priv(netdev);
831	return mii_ethtool_gset(&priv->mii, cmd);
832}
833
834static int ftmac100_set_settings(struct net_device *netdev, struct ethtool_cmd *cmd)
835{
836	struct ftmac100 *priv = netdev_priv(netdev);
837	return mii_ethtool_sset(&priv->mii, cmd);
838}
839
840static int ftmac100_nway_reset(struct net_device *netdev)
841{
842	struct ftmac100 *priv = netdev_priv(netdev);
843	return mii_nway_restart(&priv->mii);
844}
845
846static u32 ftmac100_get_link(struct net_device *netdev)
847{
848	struct ftmac100 *priv = netdev_priv(netdev);
849	return mii_link_ok(&priv->mii);
850}
851
852static const struct ethtool_ops ftmac100_ethtool_ops = {
853	.set_settings		= ftmac100_set_settings,
854	.get_settings		= ftmac100_get_settings,
855	.get_drvinfo		= ftmac100_get_drvinfo,
856	.nway_reset		= ftmac100_nway_reset,
857	.get_link		= ftmac100_get_link,
858};
859
860/******************************************************************************
861 * interrupt handler
862 *****************************************************************************/
863static irqreturn_t ftmac100_interrupt(int irq, void *dev_id)
864{
865	struct net_device *netdev = dev_id;
866	struct ftmac100 *priv = netdev_priv(netdev);
867
868	if (likely(netif_running(netdev))) {
869		/* Disable interrupts for polling */
870		ftmac100_disable_all_int(priv);
871		napi_schedule(&priv->napi);
872	}
873
874	return IRQ_HANDLED;
875}
876
877/******************************************************************************
878 * struct napi_struct functions
879 *****************************************************************************/
880static int ftmac100_poll(struct napi_struct *napi, int budget)
881{
882	struct ftmac100 *priv = container_of(napi, struct ftmac100, napi);
883	struct net_device *netdev = priv->netdev;
884	unsigned int status;
885	bool completed = true;
886	int rx = 0;
887
888	status = ioread32(priv->base + FTMAC100_OFFSET_ISR);
889
890	if (status & (FTMAC100_INT_RPKT_FINISH | FTMAC100_INT_NORXBUF)) {
891		/*
892		 * FTMAC100_INT_RPKT_FINISH:
893		 *	RX DMA has received packets into RX buffer successfully
894		 *
895		 * FTMAC100_INT_NORXBUF:
896		 *	RX buffer unavailable
897		 */
898		bool retry;
899
900		do {
901			retry = ftmac100_rx_packet(priv, &rx);
902		} while (retry && rx < budget);
903
904		if (retry && rx == budget)
905			completed = false;
906	}
907
908	if (status & (FTMAC100_INT_XPKT_OK | FTMAC100_INT_XPKT_LOST)) {
909		/*
910		 * FTMAC100_INT_XPKT_OK:
911		 *	packet transmitted to ethernet successfully
912		 *
913		 * FTMAC100_INT_XPKT_LOST:
914		 *	packet transmitted to ethernet lost due to late
915		 *	collision or excessive collision
916		 */
917		ftmac100_tx_complete(priv);
918	}
919
920	if (status & (FTMAC100_INT_NORXBUF | FTMAC100_INT_RPKT_LOST |
921		      FTMAC100_INT_AHB_ERR | FTMAC100_INT_PHYSTS_CHG)) {
922		if (net_ratelimit())
923			netdev_info(netdev, "[ISR] = 0x%x: %s%s%s%s\n", status,
924				    status & FTMAC100_INT_NORXBUF ? "NORXBUF " : "",
925				    status & FTMAC100_INT_RPKT_LOST ? "RPKT_LOST " : "",
926				    status & FTMAC100_INT_AHB_ERR ? "AHB_ERR " : "",
927				    status & FTMAC100_INT_PHYSTS_CHG ? "PHYSTS_CHG" : "");
928
929		if (status & FTMAC100_INT_NORXBUF) {
930			/* RX buffer unavailable */
931			netdev->stats.rx_over_errors++;
932		}
933
934		if (status & FTMAC100_INT_RPKT_LOST) {
935			/* received packet lost due to RX FIFO full */
936			netdev->stats.rx_fifo_errors++;
937		}
938
939		if (status & FTMAC100_INT_PHYSTS_CHG) {
940			/* PHY link status change */
941			mii_check_link(&priv->mii);
942		}
943	}
944
945	if (completed) {
946		/* stop polling */
947		napi_complete(napi);
948		ftmac100_enable_all_int(priv);
949	}
950
951	return rx;
952}
953
954/******************************************************************************
955 * struct net_device_ops functions
956 *****************************************************************************/
957static int ftmac100_open(struct net_device *netdev)
958{
959	struct ftmac100 *priv = netdev_priv(netdev);
960	int err;
961
962	err = ftmac100_alloc_buffers(priv);
963	if (err) {
964		netdev_err(netdev, "failed to allocate buffers\n");
965		goto err_alloc;
966	}
967
968	err = request_irq(priv->irq, ftmac100_interrupt, 0, netdev->name, netdev);
969	if (err) {
970		netdev_err(netdev, "failed to request irq %d\n", priv->irq);
971		goto err_irq;
972	}
973
974	priv->rx_pointer = 0;
975	priv->tx_clean_pointer = 0;
976	priv->tx_pointer = 0;
977	priv->tx_pending = 0;
978
979	err = ftmac100_start_hw(priv);
980	if (err)
981		goto err_hw;
982
983	napi_enable(&priv->napi);
984	netif_start_queue(netdev);
985
986	ftmac100_enable_all_int(priv);
987
988	return 0;
989
990err_hw:
991	free_irq(priv->irq, netdev);
992err_irq:
993	ftmac100_free_buffers(priv);
994err_alloc:
995	return err;
996}
997
998static int ftmac100_stop(struct net_device *netdev)
999{
1000	struct ftmac100 *priv = netdev_priv(netdev);
1001
1002	ftmac100_disable_all_int(priv);
1003	netif_stop_queue(netdev);
1004	napi_disable(&priv->napi);
1005	ftmac100_stop_hw(priv);
1006	free_irq(priv->irq, netdev);
1007	ftmac100_free_buffers(priv);
1008
1009	return 0;
1010}
1011
1012static int ftmac100_hard_start_xmit(struct sk_buff *skb, struct net_device *netdev)
1013{
1014	struct ftmac100 *priv = netdev_priv(netdev);
1015	dma_addr_t map;
1016
1017	if (unlikely(skb->len > MAX_PKT_SIZE)) {
1018		if (net_ratelimit())
1019			netdev_dbg(netdev, "tx packet too big\n");
1020
1021		netdev->stats.tx_dropped++;
1022		dev_kfree_skb(skb);
1023		return NETDEV_TX_OK;
1024	}
1025
1026	map = dma_map_single(priv->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
1027	if (unlikely(dma_mapping_error(priv->dev, map))) {
1028		/* drop packet */
1029		if (net_ratelimit())
1030			netdev_err(netdev, "map socket buffer failed\n");
1031
1032		netdev->stats.tx_dropped++;
1033		dev_kfree_skb(skb);
1034		return NETDEV_TX_OK;
1035	}
1036
1037	return ftmac100_xmit(priv, skb, map);
1038}
1039
1040/* optional */
1041static int ftmac100_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1042{
1043	struct ftmac100 *priv = netdev_priv(netdev);
1044	struct mii_ioctl_data *data = if_mii(ifr);
1045
1046	return generic_mii_ioctl(&priv->mii, data, cmd, NULL);
1047}
1048
1049static const struct net_device_ops ftmac100_netdev_ops = {
1050	.ndo_open		= ftmac100_open,
1051	.ndo_stop		= ftmac100_stop,
1052	.ndo_start_xmit		= ftmac100_hard_start_xmit,
1053	.ndo_set_mac_address	= eth_mac_addr,
1054	.ndo_validate_addr	= eth_validate_addr,
1055	.ndo_do_ioctl		= ftmac100_do_ioctl,
1056};
1057
1058/******************************************************************************
1059 * struct platform_driver functions
1060 *****************************************************************************/
1061static int ftmac100_probe(struct platform_device *pdev)
1062{
1063	struct resource *res;
1064	int irq;
1065	struct net_device *netdev;
1066	struct ftmac100 *priv;
1067	int err;
1068
1069	if (!pdev)
1070		return -ENODEV;
1071
1072	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1073	if (!res)
1074		return -ENXIO;
1075
1076	irq = platform_get_irq(pdev, 0);
1077	if (irq < 0)
1078		return irq;
1079
1080	/* setup net_device */
1081	netdev = alloc_etherdev(sizeof(*priv));
1082	if (!netdev) {
1083		err = -ENOMEM;
1084		goto err_alloc_etherdev;
1085	}
1086
1087	SET_NETDEV_DEV(netdev, &pdev->dev);
1088	netdev->ethtool_ops = &ftmac100_ethtool_ops;
1089	netdev->netdev_ops = &ftmac100_netdev_ops;
1090
1091	platform_set_drvdata(pdev, netdev);
1092
1093	/* setup private data */
1094	priv = netdev_priv(netdev);
1095	priv->netdev = netdev;
1096	priv->dev = &pdev->dev;
1097
1098	spin_lock_init(&priv->tx_lock);
1099
1100	/* initialize NAPI */
1101	netif_napi_add(netdev, &priv->napi, ftmac100_poll, 64);
1102
1103	/* map io memory */
1104	priv->res = request_mem_region(res->start, resource_size(res),
1105				       dev_name(&pdev->dev));
1106	if (!priv->res) {
1107		dev_err(&pdev->dev, "Could not reserve memory region\n");
1108		err = -ENOMEM;
1109		goto err_req_mem;
1110	}
1111
1112	priv->base = ioremap(res->start, resource_size(res));
1113	if (!priv->base) {
1114		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1115		err = -EIO;
1116		goto err_ioremap;
1117	}
1118
1119	priv->irq = irq;
1120
1121	/* initialize struct mii_if_info */
1122	priv->mii.phy_id	= 0;
1123	priv->mii.phy_id_mask	= 0x1f;
1124	priv->mii.reg_num_mask	= 0x1f;
1125	priv->mii.dev		= netdev;
1126	priv->mii.mdio_read	= ftmac100_mdio_read;
1127	priv->mii.mdio_write	= ftmac100_mdio_write;
1128
1129	/* register network device */
1130	err = register_netdev(netdev);
1131	if (err) {
1132		dev_err(&pdev->dev, "Failed to register netdev\n");
1133		goto err_register_netdev;
1134	}
1135
1136	netdev_info(netdev, "irq %d, mapped at %p\n", priv->irq, priv->base);
1137
1138	if (!is_valid_ether_addr(netdev->dev_addr)) {
1139		eth_hw_addr_random(netdev);
1140		netdev_info(netdev, "generated random MAC address %pM\n",
1141			    netdev->dev_addr);
1142	}
1143
1144	return 0;
1145
1146err_register_netdev:
1147	iounmap(priv->base);
1148err_ioremap:
1149	release_resource(priv->res);
1150err_req_mem:
1151	netif_napi_del(&priv->napi);
1152	free_netdev(netdev);
1153err_alloc_etherdev:
1154	return err;
1155}
1156
1157static int __exit ftmac100_remove(struct platform_device *pdev)
1158{
1159	struct net_device *netdev;
1160	struct ftmac100 *priv;
1161
1162	netdev = platform_get_drvdata(pdev);
1163	priv = netdev_priv(netdev);
1164
1165	unregister_netdev(netdev);
1166
1167	iounmap(priv->base);
1168	release_resource(priv->res);
1169
1170	netif_napi_del(&priv->napi);
1171	free_netdev(netdev);
1172	return 0;
1173}
1174
1175static struct platform_driver ftmac100_driver = {
1176	.probe		= ftmac100_probe,
1177	.remove		= __exit_p(ftmac100_remove),
1178	.driver		= {
1179		.name	= DRV_NAME,
1180	},
1181};
1182
1183/******************************************************************************
1184 * initialization / finalization
1185 *****************************************************************************/
1186static int __init ftmac100_init(void)
1187{
1188	pr_info("Loading version " DRV_VERSION " ...\n");
1189	return platform_driver_register(&ftmac100_driver);
1190}
1191
1192static void __exit ftmac100_exit(void)
1193{
1194	platform_driver_unregister(&ftmac100_driver);
1195}
1196
1197module_init(ftmac100_init);
1198module_exit(ftmac100_exit);
1199
1200MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
1201MODULE_DESCRIPTION("FTMAC100 driver");
1202MODULE_LICENSE("GPL");
1203