1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Faraday FTGMAC100 Gigabit 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/clk.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/etherdevice.h>
14 #include <linux/ethtool.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/module.h>
18 #include <linux/netdevice.h>
19 #include <linux/of.h>
20 #include <linux/of_mdio.h>
21 #include <linux/phy.h>
22 #include <linux/platform_device.h>
23 #include <linux/property.h>
24 #include <linux/crc32.h>
25 #include <linux/if_vlan.h>
26 #include <linux/of_net.h>
27 #include <net/ip.h>
28 #include <net/ncsi.h>
29 
30 #include "ftgmac100.h"
31 
32 #define DRV_NAME	"ftgmac100"
33 
34 /* Arbitrary values, I am not sure the HW has limits */
35 #define MAX_RX_QUEUE_ENTRIES	1024
36 #define MAX_TX_QUEUE_ENTRIES	1024
37 #define MIN_RX_QUEUE_ENTRIES	32
38 #define MIN_TX_QUEUE_ENTRIES	32
39 
40 /* Defaults */
41 #define DEF_RX_QUEUE_ENTRIES	128
42 #define DEF_TX_QUEUE_ENTRIES	128
43 
44 #define MAX_PKT_SIZE		1536
45 #define RX_BUF_SIZE		MAX_PKT_SIZE	/* must be smaller than 0x3fff */
46 
47 /* Min number of tx ring entries before stopping queue */
48 #define TX_THRESHOLD		(MAX_SKB_FRAGS + 1)
49 
50 #define FTGMAC_100MHZ		100000000
51 #define FTGMAC_25MHZ		25000000
52 
53 struct ftgmac100 {
54 	/* Registers */
55 	struct resource *res;
56 	void __iomem *base;
57 
58 	/* Rx ring */
59 	unsigned int rx_q_entries;
60 	struct ftgmac100_rxdes *rxdes;
61 	dma_addr_t rxdes_dma;
62 	struct sk_buff **rx_skbs;
63 	unsigned int rx_pointer;
64 	u32 rxdes0_edorr_mask;
65 
66 	/* Tx ring */
67 	unsigned int tx_q_entries;
68 	struct ftgmac100_txdes *txdes;
69 	dma_addr_t txdes_dma;
70 	struct sk_buff **tx_skbs;
71 	unsigned int tx_clean_pointer;
72 	unsigned int tx_pointer;
73 	u32 txdes0_edotr_mask;
74 
75 	/* Used to signal the reset task of ring change request */
76 	unsigned int new_rx_q_entries;
77 	unsigned int new_tx_q_entries;
78 
79 	/* Scratch page to use when rx skb alloc fails */
80 	void *rx_scratch;
81 	dma_addr_t rx_scratch_dma;
82 
83 	/* Component structures */
84 	struct net_device *netdev;
85 	struct device *dev;
86 	struct ncsi_dev *ndev;
87 	struct napi_struct napi;
88 	struct work_struct reset_task;
89 	struct mii_bus *mii_bus;
90 	struct clk *clk;
91 
92 	/* AST2500/AST2600 RMII ref clock gate */
93 	struct clk *rclk;
94 
95 	/* Link management */
96 	int cur_speed;
97 	int cur_duplex;
98 	bool use_ncsi;
99 
100 	/* Multicast filter settings */
101 	u32 maht0;
102 	u32 maht1;
103 
104 	/* Flow control settings */
105 	bool tx_pause;
106 	bool rx_pause;
107 	bool aneg_pause;
108 
109 	/* Misc */
110 	bool need_mac_restart;
111 	bool is_aspeed;
112 };
113 
114 static int ftgmac100_reset_mac(struct ftgmac100 *priv, u32 maccr)
115 {
116 	struct net_device *netdev = priv->netdev;
117 	int i;
118 
119 	/* NOTE: reset clears all registers */
120 	iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
121 	iowrite32(maccr | FTGMAC100_MACCR_SW_RST,
122 		  priv->base + FTGMAC100_OFFSET_MACCR);
123 	for (i = 0; i < 200; i++) {
124 		unsigned int maccr;
125 
126 		maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
127 		if (!(maccr & FTGMAC100_MACCR_SW_RST))
128 			return 0;
129 
130 		udelay(1);
131 	}
132 
133 	netdev_err(netdev, "Hardware reset failed\n");
134 	return -EIO;
135 }
136 
137 static int ftgmac100_reset_and_config_mac(struct ftgmac100 *priv)
138 {
139 	u32 maccr = 0;
140 
141 	switch (priv->cur_speed) {
142 	case SPEED_10:
143 	case 0: /* no link */
144 		break;
145 
146 	case SPEED_100:
147 		maccr |= FTGMAC100_MACCR_FAST_MODE;
148 		break;
149 
150 	case SPEED_1000:
151 		maccr |= FTGMAC100_MACCR_GIGA_MODE;
152 		break;
153 	default:
154 		netdev_err(priv->netdev, "Unknown speed %d !\n",
155 			   priv->cur_speed);
156 		break;
157 	}
158 
159 	/* (Re)initialize the queue pointers */
160 	priv->rx_pointer = 0;
161 	priv->tx_clean_pointer = 0;
162 	priv->tx_pointer = 0;
163 
164 	/* The doc says reset twice with 10us interval */
165 	if (ftgmac100_reset_mac(priv, maccr))
166 		return -EIO;
167 	usleep_range(10, 1000);
168 	return ftgmac100_reset_mac(priv, maccr);
169 }
170 
171 static void ftgmac100_write_mac_addr(struct ftgmac100 *priv, const u8 *mac)
172 {
173 	unsigned int maddr = mac[0] << 8 | mac[1];
174 	unsigned int laddr = mac[2] << 24 | mac[3] << 16 | mac[4] << 8 | mac[5];
175 
176 	iowrite32(maddr, priv->base + FTGMAC100_OFFSET_MAC_MADR);
177 	iowrite32(laddr, priv->base + FTGMAC100_OFFSET_MAC_LADR);
178 }
179 
180 static void ftgmac100_initial_mac(struct ftgmac100 *priv)
181 {
182 	u8 mac[ETH_ALEN];
183 	unsigned int m;
184 	unsigned int l;
185 	void *addr;
186 
187 	addr = device_get_mac_address(priv->dev, mac, ETH_ALEN);
188 	if (addr) {
189 		ether_addr_copy(priv->netdev->dev_addr, mac);
190 		dev_info(priv->dev, "Read MAC address %pM from device tree\n",
191 			 mac);
192 		return;
193 	}
194 
195 	m = ioread32(priv->base + FTGMAC100_OFFSET_MAC_MADR);
196 	l = ioread32(priv->base + FTGMAC100_OFFSET_MAC_LADR);
197 
198 	mac[0] = (m >> 8) & 0xff;
199 	mac[1] = m & 0xff;
200 	mac[2] = (l >> 24) & 0xff;
201 	mac[3] = (l >> 16) & 0xff;
202 	mac[4] = (l >> 8) & 0xff;
203 	mac[5] = l & 0xff;
204 
205 	if (is_valid_ether_addr(mac)) {
206 		ether_addr_copy(priv->netdev->dev_addr, mac);
207 		dev_info(priv->dev, "Read MAC address %pM from chip\n", mac);
208 	} else {
209 		eth_hw_addr_random(priv->netdev);
210 		dev_info(priv->dev, "Generated random MAC address %pM\n",
211 			 priv->netdev->dev_addr);
212 	}
213 }
214 
215 static int ftgmac100_set_mac_addr(struct net_device *dev, void *p)
216 {
217 	int ret;
218 
219 	ret = eth_prepare_mac_addr_change(dev, p);
220 	if (ret < 0)
221 		return ret;
222 
223 	eth_commit_mac_addr_change(dev, p);
224 	ftgmac100_write_mac_addr(netdev_priv(dev), dev->dev_addr);
225 
226 	return 0;
227 }
228 
229 static void ftgmac100_config_pause(struct ftgmac100 *priv)
230 {
231 	u32 fcr = FTGMAC100_FCR_PAUSE_TIME(16);
232 
233 	/* Throttle tx queue when receiving pause frames */
234 	if (priv->rx_pause)
235 		fcr |= FTGMAC100_FCR_FC_EN;
236 
237 	/* Enables sending pause frames when the RX queue is past a
238 	 * certain threshold.
239 	 */
240 	if (priv->tx_pause)
241 		fcr |= FTGMAC100_FCR_FCTHR_EN;
242 
243 	iowrite32(fcr, priv->base + FTGMAC100_OFFSET_FCR);
244 }
245 
246 static void ftgmac100_init_hw(struct ftgmac100 *priv)
247 {
248 	u32 reg, rfifo_sz, tfifo_sz;
249 
250 	/* Clear stale interrupts */
251 	reg = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
252 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_ISR);
253 
254 	/* Setup RX ring buffer base */
255 	iowrite32(priv->rxdes_dma, priv->base + FTGMAC100_OFFSET_RXR_BADR);
256 
257 	/* Setup TX ring buffer base */
258 	iowrite32(priv->txdes_dma, priv->base + FTGMAC100_OFFSET_NPTXR_BADR);
259 
260 	/* Configure RX buffer size */
261 	iowrite32(FTGMAC100_RBSR_SIZE(RX_BUF_SIZE),
262 		  priv->base + FTGMAC100_OFFSET_RBSR);
263 
264 	/* Set RX descriptor autopoll */
265 	iowrite32(FTGMAC100_APTC_RXPOLL_CNT(1),
266 		  priv->base + FTGMAC100_OFFSET_APTC);
267 
268 	/* Write MAC address */
269 	ftgmac100_write_mac_addr(priv, priv->netdev->dev_addr);
270 
271 	/* Write multicast filter */
272 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
273 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
274 
275 	/* Configure descriptor sizes and increase burst sizes according
276 	 * to values in Aspeed SDK. The FIFO arbitration is enabled and
277 	 * the thresholds set based on the recommended values in the
278 	 * AST2400 specification.
279 	 */
280 	iowrite32(FTGMAC100_DBLAC_RXDES_SIZE(2) |   /* 2*8 bytes RX descs */
281 		  FTGMAC100_DBLAC_TXDES_SIZE(2) |   /* 2*8 bytes TX descs */
282 		  FTGMAC100_DBLAC_RXBURST_SIZE(3) | /* 512 bytes max RX bursts */
283 		  FTGMAC100_DBLAC_TXBURST_SIZE(3) | /* 512 bytes max TX bursts */
284 		  FTGMAC100_DBLAC_RX_THR_EN |       /* Enable fifo threshold arb */
285 		  FTGMAC100_DBLAC_RXFIFO_HTHR(6) |  /* 6/8 of FIFO high threshold */
286 		  FTGMAC100_DBLAC_RXFIFO_LTHR(2),   /* 2/8 of FIFO low threshold */
287 		  priv->base + FTGMAC100_OFFSET_DBLAC);
288 
289 	/* Interrupt mitigation configured for 1 interrupt/packet. HW interrupt
290 	 * mitigation doesn't seem to provide any benefit with NAPI so leave
291 	 * it at that.
292 	 */
293 	iowrite32(FTGMAC100_ITC_RXINT_THR(1) |
294 		  FTGMAC100_ITC_TXINT_THR(1),
295 		  priv->base + FTGMAC100_OFFSET_ITC);
296 
297 	/* Configure FIFO sizes in the TPAFCR register */
298 	reg = ioread32(priv->base + FTGMAC100_OFFSET_FEAR);
299 	rfifo_sz = reg & 0x00000007;
300 	tfifo_sz = (reg >> 3) & 0x00000007;
301 	reg = ioread32(priv->base + FTGMAC100_OFFSET_TPAFCR);
302 	reg &= ~0x3f000000;
303 	reg |= (tfifo_sz << 27);
304 	reg |= (rfifo_sz << 24);
305 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_TPAFCR);
306 }
307 
308 static void ftgmac100_start_hw(struct ftgmac100 *priv)
309 {
310 	u32 maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
311 
312 	/* Keep the original GMAC and FAST bits */
313 	maccr &= (FTGMAC100_MACCR_FAST_MODE | FTGMAC100_MACCR_GIGA_MODE);
314 
315 	/* Add all the main enable bits */
316 	maccr |= FTGMAC100_MACCR_TXDMA_EN	|
317 		 FTGMAC100_MACCR_RXDMA_EN	|
318 		 FTGMAC100_MACCR_TXMAC_EN	|
319 		 FTGMAC100_MACCR_RXMAC_EN	|
320 		 FTGMAC100_MACCR_CRC_APD	|
321 		 FTGMAC100_MACCR_PHY_LINK_LEVEL	|
322 		 FTGMAC100_MACCR_RX_RUNT	|
323 		 FTGMAC100_MACCR_RX_BROADPKT;
324 
325 	/* Add other bits as needed */
326 	if (priv->cur_duplex == DUPLEX_FULL)
327 		maccr |= FTGMAC100_MACCR_FULLDUP;
328 	if (priv->netdev->flags & IFF_PROMISC)
329 		maccr |= FTGMAC100_MACCR_RX_ALL;
330 	if (priv->netdev->flags & IFF_ALLMULTI)
331 		maccr |= FTGMAC100_MACCR_RX_MULTIPKT;
332 	else if (netdev_mc_count(priv->netdev))
333 		maccr |= FTGMAC100_MACCR_HT_MULTI_EN;
334 
335 	/* Vlan filtering enabled */
336 	if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
337 		maccr |= FTGMAC100_MACCR_RM_VLAN;
338 
339 	/* Hit the HW */
340 	iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
341 }
342 
343 static void ftgmac100_stop_hw(struct ftgmac100 *priv)
344 {
345 	iowrite32(0, priv->base + FTGMAC100_OFFSET_MACCR);
346 }
347 
348 static void ftgmac100_calc_mc_hash(struct ftgmac100 *priv)
349 {
350 	struct netdev_hw_addr *ha;
351 
352 	priv->maht1 = 0;
353 	priv->maht0 = 0;
354 	netdev_for_each_mc_addr(ha, priv->netdev) {
355 		u32 crc_val = ether_crc_le(ETH_ALEN, ha->addr);
356 
357 		crc_val = (~(crc_val >> 2)) & 0x3f;
358 		if (crc_val >= 32)
359 			priv->maht1 |= 1ul << (crc_val - 32);
360 		else
361 			priv->maht0 |= 1ul << (crc_val);
362 	}
363 }
364 
365 static void ftgmac100_set_rx_mode(struct net_device *netdev)
366 {
367 	struct ftgmac100 *priv = netdev_priv(netdev);
368 
369 	/* Setup the hash filter */
370 	ftgmac100_calc_mc_hash(priv);
371 
372 	/* Interface down ? that's all there is to do */
373 	if (!netif_running(netdev))
374 		return;
375 
376 	/* Update the HW */
377 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
378 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
379 
380 	/* Reconfigure MACCR */
381 	ftgmac100_start_hw(priv);
382 }
383 
384 static int ftgmac100_alloc_rx_buf(struct ftgmac100 *priv, unsigned int entry,
385 				  struct ftgmac100_rxdes *rxdes, gfp_t gfp)
386 {
387 	struct net_device *netdev = priv->netdev;
388 	struct sk_buff *skb;
389 	dma_addr_t map;
390 	int err = 0;
391 
392 	skb = netdev_alloc_skb_ip_align(netdev, RX_BUF_SIZE);
393 	if (unlikely(!skb)) {
394 		if (net_ratelimit())
395 			netdev_warn(netdev, "failed to allocate rx skb\n");
396 		err = -ENOMEM;
397 		map = priv->rx_scratch_dma;
398 	} else {
399 		map = dma_map_single(priv->dev, skb->data, RX_BUF_SIZE,
400 				     DMA_FROM_DEVICE);
401 		if (unlikely(dma_mapping_error(priv->dev, map))) {
402 			if (net_ratelimit())
403 				netdev_err(netdev, "failed to map rx page\n");
404 			dev_kfree_skb_any(skb);
405 			map = priv->rx_scratch_dma;
406 			skb = NULL;
407 			err = -ENOMEM;
408 		}
409 	}
410 
411 	/* Store skb */
412 	priv->rx_skbs[entry] = skb;
413 
414 	/* Store DMA address into RX desc */
415 	rxdes->rxdes3 = cpu_to_le32(map);
416 
417 	/* Ensure the above is ordered vs clearing the OWN bit */
418 	dma_wmb();
419 
420 	/* Clean status (which resets own bit) */
421 	if (entry == (priv->rx_q_entries - 1))
422 		rxdes->rxdes0 = cpu_to_le32(priv->rxdes0_edorr_mask);
423 	else
424 		rxdes->rxdes0 = 0;
425 
426 	return err;
427 }
428 
429 static unsigned int ftgmac100_next_rx_pointer(struct ftgmac100 *priv,
430 					      unsigned int pointer)
431 {
432 	return (pointer + 1) & (priv->rx_q_entries - 1);
433 }
434 
435 static void ftgmac100_rx_packet_error(struct ftgmac100 *priv, u32 status)
436 {
437 	struct net_device *netdev = priv->netdev;
438 
439 	if (status & FTGMAC100_RXDES0_RX_ERR)
440 		netdev->stats.rx_errors++;
441 
442 	if (status & FTGMAC100_RXDES0_CRC_ERR)
443 		netdev->stats.rx_crc_errors++;
444 
445 	if (status & (FTGMAC100_RXDES0_FTL |
446 		      FTGMAC100_RXDES0_RUNT |
447 		      FTGMAC100_RXDES0_RX_ODD_NB))
448 		netdev->stats.rx_length_errors++;
449 }
450 
451 static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed)
452 {
453 	struct net_device *netdev = priv->netdev;
454 	struct ftgmac100_rxdes *rxdes;
455 	struct sk_buff *skb;
456 	unsigned int pointer, size;
457 	u32 status, csum_vlan;
458 	dma_addr_t map;
459 
460 	/* Grab next RX descriptor */
461 	pointer = priv->rx_pointer;
462 	rxdes = &priv->rxdes[pointer];
463 
464 	/* Grab descriptor status */
465 	status = le32_to_cpu(rxdes->rxdes0);
466 
467 	/* Do we have a packet ? */
468 	if (!(status & FTGMAC100_RXDES0_RXPKT_RDY))
469 		return false;
470 
471 	/* Order subsequent reads with the test for the ready bit */
472 	dma_rmb();
473 
474 	/* We don't cope with fragmented RX packets */
475 	if (unlikely(!(status & FTGMAC100_RXDES0_FRS) ||
476 		     !(status & FTGMAC100_RXDES0_LRS)))
477 		goto drop;
478 
479 	/* Grab received size and csum vlan field in the descriptor */
480 	size = status & FTGMAC100_RXDES0_VDBC;
481 	csum_vlan = le32_to_cpu(rxdes->rxdes1);
482 
483 	/* Any error (other than csum offload) flagged ? */
484 	if (unlikely(status & RXDES0_ANY_ERROR)) {
485 		/* Correct for incorrect flagging of runt packets
486 		 * with vlan tags... Just accept a runt packet that
487 		 * has been flagged as vlan and whose size is at
488 		 * least 60 bytes.
489 		 */
490 		if ((status & FTGMAC100_RXDES0_RUNT) &&
491 		    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL) &&
492 		    (size >= 60))
493 			status &= ~FTGMAC100_RXDES0_RUNT;
494 
495 		/* Any error still in there ? */
496 		if (status & RXDES0_ANY_ERROR) {
497 			ftgmac100_rx_packet_error(priv, status);
498 			goto drop;
499 		}
500 	}
501 
502 	/* If the packet had no skb (failed to allocate earlier)
503 	 * then try to allocate one and skip
504 	 */
505 	skb = priv->rx_skbs[pointer];
506 	if (!unlikely(skb)) {
507 		ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
508 		goto drop;
509 	}
510 
511 	if (unlikely(status & FTGMAC100_RXDES0_MULTICAST))
512 		netdev->stats.multicast++;
513 
514 	/* If the HW found checksum errors, bounce it to software.
515 	 *
516 	 * If we didn't, we need to see if the packet was recognized
517 	 * by HW as one of the supported checksummed protocols before
518 	 * we accept the HW test results.
519 	 */
520 	if (netdev->features & NETIF_F_RXCSUM) {
521 		u32 err_bits = FTGMAC100_RXDES1_TCP_CHKSUM_ERR |
522 			FTGMAC100_RXDES1_UDP_CHKSUM_ERR |
523 			FTGMAC100_RXDES1_IP_CHKSUM_ERR;
524 		if ((csum_vlan & err_bits) ||
525 		    !(csum_vlan & FTGMAC100_RXDES1_PROT_MASK))
526 			skb->ip_summed = CHECKSUM_NONE;
527 		else
528 			skb->ip_summed = CHECKSUM_UNNECESSARY;
529 	}
530 
531 	/* Transfer received size to skb */
532 	skb_put(skb, size);
533 
534 	/* Extract vlan tag */
535 	if ((netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
536 	    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL))
537 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
538 				       csum_vlan & 0xffff);
539 
540 	/* Tear down DMA mapping, do necessary cache management */
541 	map = le32_to_cpu(rxdes->rxdes3);
542 
543 #if defined(CONFIG_ARM) && !defined(CONFIG_ARM_DMA_USE_IOMMU)
544 	/* When we don't have an iommu, we can save cycles by not
545 	 * invalidating the cache for the part of the packet that
546 	 * wasn't received.
547 	 */
548 	dma_unmap_single(priv->dev, map, size, DMA_FROM_DEVICE);
549 #else
550 	dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
551 #endif
552 
553 
554 	/* Resplenish rx ring */
555 	ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
556 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
557 
558 	skb->protocol = eth_type_trans(skb, netdev);
559 
560 	netdev->stats.rx_packets++;
561 	netdev->stats.rx_bytes += size;
562 
563 	/* push packet to protocol stack */
564 	if (skb->ip_summed == CHECKSUM_NONE)
565 		netif_receive_skb(skb);
566 	else
567 		napi_gro_receive(&priv->napi, skb);
568 
569 	(*processed)++;
570 	return true;
571 
572  drop:
573 	/* Clean rxdes0 (which resets own bit) */
574 	rxdes->rxdes0 = cpu_to_le32(status & priv->rxdes0_edorr_mask);
575 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
576 	netdev->stats.rx_dropped++;
577 	return true;
578 }
579 
580 static u32 ftgmac100_base_tx_ctlstat(struct ftgmac100 *priv,
581 				     unsigned int index)
582 {
583 	if (index == (priv->tx_q_entries - 1))
584 		return priv->txdes0_edotr_mask;
585 	else
586 		return 0;
587 }
588 
589 static unsigned int ftgmac100_next_tx_pointer(struct ftgmac100 *priv,
590 					      unsigned int pointer)
591 {
592 	return (pointer + 1) & (priv->tx_q_entries - 1);
593 }
594 
595 static u32 ftgmac100_tx_buf_avail(struct ftgmac100 *priv)
596 {
597 	/* Returns the number of available slots in the TX queue
598 	 *
599 	 * This always leaves one free slot so we don't have to
600 	 * worry about empty vs. full, and this simplifies the
601 	 * test for ftgmac100_tx_buf_cleanable() below
602 	 */
603 	return (priv->tx_clean_pointer - priv->tx_pointer - 1) &
604 		(priv->tx_q_entries - 1);
605 }
606 
607 static bool ftgmac100_tx_buf_cleanable(struct ftgmac100 *priv)
608 {
609 	return priv->tx_pointer != priv->tx_clean_pointer;
610 }
611 
612 static void ftgmac100_free_tx_packet(struct ftgmac100 *priv,
613 				     unsigned int pointer,
614 				     struct sk_buff *skb,
615 				     struct ftgmac100_txdes *txdes,
616 				     u32 ctl_stat)
617 {
618 	dma_addr_t map = le32_to_cpu(txdes->txdes3);
619 	size_t len;
620 
621 	if (ctl_stat & FTGMAC100_TXDES0_FTS) {
622 		len = skb_headlen(skb);
623 		dma_unmap_single(priv->dev, map, len, DMA_TO_DEVICE);
624 	} else {
625 		len = FTGMAC100_TXDES0_TXBUF_SIZE(ctl_stat);
626 		dma_unmap_page(priv->dev, map, len, DMA_TO_DEVICE);
627 	}
628 
629 	/* Free SKB on last segment */
630 	if (ctl_stat & FTGMAC100_TXDES0_LTS)
631 		dev_kfree_skb(skb);
632 	priv->tx_skbs[pointer] = NULL;
633 }
634 
635 static bool ftgmac100_tx_complete_packet(struct ftgmac100 *priv)
636 {
637 	struct net_device *netdev = priv->netdev;
638 	struct ftgmac100_txdes *txdes;
639 	struct sk_buff *skb;
640 	unsigned int pointer;
641 	u32 ctl_stat;
642 
643 	pointer = priv->tx_clean_pointer;
644 	txdes = &priv->txdes[pointer];
645 
646 	ctl_stat = le32_to_cpu(txdes->txdes0);
647 	if (ctl_stat & FTGMAC100_TXDES0_TXDMA_OWN)
648 		return false;
649 
650 	skb = priv->tx_skbs[pointer];
651 	netdev->stats.tx_packets++;
652 	netdev->stats.tx_bytes += skb->len;
653 	ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
654 	txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
655 
656 	priv->tx_clean_pointer = ftgmac100_next_tx_pointer(priv, pointer);
657 
658 	return true;
659 }
660 
661 static void ftgmac100_tx_complete(struct ftgmac100 *priv)
662 {
663 	struct net_device *netdev = priv->netdev;
664 
665 	/* Process all completed packets */
666 	while (ftgmac100_tx_buf_cleanable(priv) &&
667 	       ftgmac100_tx_complete_packet(priv))
668 		;
669 
670 	/* Restart queue if needed */
671 	smp_mb();
672 	if (unlikely(netif_queue_stopped(netdev) &&
673 		     ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)) {
674 		struct netdev_queue *txq;
675 
676 		txq = netdev_get_tx_queue(netdev, 0);
677 		__netif_tx_lock(txq, smp_processor_id());
678 		if (netif_queue_stopped(netdev) &&
679 		    ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
680 			netif_wake_queue(netdev);
681 		__netif_tx_unlock(txq);
682 	}
683 }
684 
685 static bool ftgmac100_prep_tx_csum(struct sk_buff *skb, u32 *csum_vlan)
686 {
687 	if (skb->protocol == cpu_to_be16(ETH_P_IP)) {
688 		u8 ip_proto = ip_hdr(skb)->protocol;
689 
690 		*csum_vlan |= FTGMAC100_TXDES1_IP_CHKSUM;
691 		switch(ip_proto) {
692 		case IPPROTO_TCP:
693 			*csum_vlan |= FTGMAC100_TXDES1_TCP_CHKSUM;
694 			return true;
695 		case IPPROTO_UDP:
696 			*csum_vlan |= FTGMAC100_TXDES1_UDP_CHKSUM;
697 			return true;
698 		case IPPROTO_IP:
699 			return true;
700 		}
701 	}
702 	return skb_checksum_help(skb) == 0;
703 }
704 
705 static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb,
706 					     struct net_device *netdev)
707 {
708 	struct ftgmac100 *priv = netdev_priv(netdev);
709 	struct ftgmac100_txdes *txdes, *first;
710 	unsigned int pointer, nfrags, len, i, j;
711 	u32 f_ctl_stat, ctl_stat, csum_vlan;
712 	dma_addr_t map;
713 
714 	/* The HW doesn't pad small frames */
715 	if (eth_skb_pad(skb)) {
716 		netdev->stats.tx_dropped++;
717 		return NETDEV_TX_OK;
718 	}
719 
720 	/* Reject oversize packets */
721 	if (unlikely(skb->len > MAX_PKT_SIZE)) {
722 		if (net_ratelimit())
723 			netdev_dbg(netdev, "tx packet too big\n");
724 		goto drop;
725 	}
726 
727 	/* Do we have a limit on #fragments ? I yet have to get a reply
728 	 * from Aspeed. If there's one I haven't hit it.
729 	 */
730 	nfrags = skb_shinfo(skb)->nr_frags;
731 
732 	/* Setup HW checksumming */
733 	csum_vlan = 0;
734 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
735 	    !ftgmac100_prep_tx_csum(skb, &csum_vlan))
736 		goto drop;
737 
738 	/* Add VLAN tag */
739 	if (skb_vlan_tag_present(skb)) {
740 		csum_vlan |= FTGMAC100_TXDES1_INS_VLANTAG;
741 		csum_vlan |= skb_vlan_tag_get(skb) & 0xffff;
742 	}
743 
744 	/* Get header len */
745 	len = skb_headlen(skb);
746 
747 	/* Map the packet head */
748 	map = dma_map_single(priv->dev, skb->data, len, DMA_TO_DEVICE);
749 	if (dma_mapping_error(priv->dev, map)) {
750 		if (net_ratelimit())
751 			netdev_err(netdev, "map tx packet head failed\n");
752 		goto drop;
753 	}
754 
755 	/* Grab the next free tx descriptor */
756 	pointer = priv->tx_pointer;
757 	txdes = first = &priv->txdes[pointer];
758 
759 	/* Setup it up with the packet head. Don't write the head to the
760 	 * ring just yet
761 	 */
762 	priv->tx_skbs[pointer] = skb;
763 	f_ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
764 	f_ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
765 	f_ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
766 	f_ctl_stat |= FTGMAC100_TXDES0_FTS;
767 	if (nfrags == 0)
768 		f_ctl_stat |= FTGMAC100_TXDES0_LTS;
769 	txdes->txdes3 = cpu_to_le32(map);
770 	txdes->txdes1 = cpu_to_le32(csum_vlan);
771 
772 	/* Next descriptor */
773 	pointer = ftgmac100_next_tx_pointer(priv, pointer);
774 
775 	/* Add the fragments */
776 	for (i = 0; i < nfrags; i++) {
777 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
778 
779 		len = skb_frag_size(frag);
780 
781 		/* Map it */
782 		map = skb_frag_dma_map(priv->dev, frag, 0, len,
783 				       DMA_TO_DEVICE);
784 		if (dma_mapping_error(priv->dev, map))
785 			goto dma_err;
786 
787 		/* Setup descriptor */
788 		priv->tx_skbs[pointer] = skb;
789 		txdes = &priv->txdes[pointer];
790 		ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
791 		ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
792 		ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
793 		if (i == (nfrags - 1))
794 			ctl_stat |= FTGMAC100_TXDES0_LTS;
795 		txdes->txdes0 = cpu_to_le32(ctl_stat);
796 		txdes->txdes1 = 0;
797 		txdes->txdes3 = cpu_to_le32(map);
798 
799 		/* Next one */
800 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
801 	}
802 
803 	/* Order the previous packet and descriptor udpates
804 	 * before setting the OWN bit on the first descriptor.
805 	 */
806 	dma_wmb();
807 	first->txdes0 = cpu_to_le32(f_ctl_stat);
808 
809 	/* Update next TX pointer */
810 	priv->tx_pointer = pointer;
811 
812 	/* If there isn't enough room for all the fragments of a new packet
813 	 * in the TX ring, stop the queue. The sequence below is race free
814 	 * vs. a concurrent restart in ftgmac100_poll()
815 	 */
816 	if (unlikely(ftgmac100_tx_buf_avail(priv) < TX_THRESHOLD)) {
817 		netif_stop_queue(netdev);
818 		/* Order the queue stop with the test below */
819 		smp_mb();
820 		if (ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
821 			netif_wake_queue(netdev);
822 	}
823 
824 	/* Poke transmitter to read the updated TX descriptors */
825 	iowrite32(1, priv->base + FTGMAC100_OFFSET_NPTXPD);
826 
827 	return NETDEV_TX_OK;
828 
829  dma_err:
830 	if (net_ratelimit())
831 		netdev_err(netdev, "map tx fragment failed\n");
832 
833 	/* Free head */
834 	pointer = priv->tx_pointer;
835 	ftgmac100_free_tx_packet(priv, pointer, skb, first, f_ctl_stat);
836 	first->txdes0 = cpu_to_le32(f_ctl_stat & priv->txdes0_edotr_mask);
837 
838 	/* Then all fragments */
839 	for (j = 0; j < i; j++) {
840 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
841 		txdes = &priv->txdes[pointer];
842 		ctl_stat = le32_to_cpu(txdes->txdes0);
843 		ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
844 		txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
845 	}
846 
847 	/* This cannot be reached if we successfully mapped the
848 	 * last fragment, so we know ftgmac100_free_tx_packet()
849 	 * hasn't freed the skb yet.
850 	 */
851  drop:
852 	/* Drop the packet */
853 	dev_kfree_skb_any(skb);
854 	netdev->stats.tx_dropped++;
855 
856 	return NETDEV_TX_OK;
857 }
858 
859 static void ftgmac100_free_buffers(struct ftgmac100 *priv)
860 {
861 	int i;
862 
863 	/* Free all RX buffers */
864 	for (i = 0; i < priv->rx_q_entries; i++) {
865 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
866 		struct sk_buff *skb = priv->rx_skbs[i];
867 		dma_addr_t map = le32_to_cpu(rxdes->rxdes3);
868 
869 		if (!skb)
870 			continue;
871 
872 		priv->rx_skbs[i] = NULL;
873 		dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
874 		dev_kfree_skb_any(skb);
875 	}
876 
877 	/* Free all TX buffers */
878 	for (i = 0; i < priv->tx_q_entries; i++) {
879 		struct ftgmac100_txdes *txdes = &priv->txdes[i];
880 		struct sk_buff *skb = priv->tx_skbs[i];
881 
882 		if (!skb)
883 			continue;
884 		ftgmac100_free_tx_packet(priv, i, skb, txdes,
885 					 le32_to_cpu(txdes->txdes0));
886 	}
887 }
888 
889 static void ftgmac100_free_rings(struct ftgmac100 *priv)
890 {
891 	/* Free skb arrays */
892 	kfree(priv->rx_skbs);
893 	kfree(priv->tx_skbs);
894 
895 	/* Free descriptors */
896 	if (priv->rxdes)
897 		dma_free_coherent(priv->dev, MAX_RX_QUEUE_ENTRIES *
898 				  sizeof(struct ftgmac100_rxdes),
899 				  priv->rxdes, priv->rxdes_dma);
900 	priv->rxdes = NULL;
901 
902 	if (priv->txdes)
903 		dma_free_coherent(priv->dev, MAX_TX_QUEUE_ENTRIES *
904 				  sizeof(struct ftgmac100_txdes),
905 				  priv->txdes, priv->txdes_dma);
906 	priv->txdes = NULL;
907 
908 	/* Free scratch packet buffer */
909 	if (priv->rx_scratch)
910 		dma_free_coherent(priv->dev, RX_BUF_SIZE,
911 				  priv->rx_scratch, priv->rx_scratch_dma);
912 }
913 
914 static int ftgmac100_alloc_rings(struct ftgmac100 *priv)
915 {
916 	/* Allocate skb arrays */
917 	priv->rx_skbs = kcalloc(MAX_RX_QUEUE_ENTRIES, sizeof(void *),
918 				GFP_KERNEL);
919 	if (!priv->rx_skbs)
920 		return -ENOMEM;
921 	priv->tx_skbs = kcalloc(MAX_TX_QUEUE_ENTRIES, sizeof(void *),
922 				GFP_KERNEL);
923 	if (!priv->tx_skbs)
924 		return -ENOMEM;
925 
926 	/* Allocate descriptors */
927 	priv->rxdes = dma_alloc_coherent(priv->dev,
928 					 MAX_RX_QUEUE_ENTRIES * sizeof(struct ftgmac100_rxdes),
929 					 &priv->rxdes_dma, GFP_KERNEL);
930 	if (!priv->rxdes)
931 		return -ENOMEM;
932 	priv->txdes = dma_alloc_coherent(priv->dev,
933 					 MAX_TX_QUEUE_ENTRIES * sizeof(struct ftgmac100_txdes),
934 					 &priv->txdes_dma, GFP_KERNEL);
935 	if (!priv->txdes)
936 		return -ENOMEM;
937 
938 	/* Allocate scratch packet buffer */
939 	priv->rx_scratch = dma_alloc_coherent(priv->dev,
940 					      RX_BUF_SIZE,
941 					      &priv->rx_scratch_dma,
942 					      GFP_KERNEL);
943 	if (!priv->rx_scratch)
944 		return -ENOMEM;
945 
946 	return 0;
947 }
948 
949 static void ftgmac100_init_rings(struct ftgmac100 *priv)
950 {
951 	struct ftgmac100_rxdes *rxdes = NULL;
952 	struct ftgmac100_txdes *txdes = NULL;
953 	int i;
954 
955 	/* Update entries counts */
956 	priv->rx_q_entries = priv->new_rx_q_entries;
957 	priv->tx_q_entries = priv->new_tx_q_entries;
958 
959 	if (WARN_ON(priv->rx_q_entries < MIN_RX_QUEUE_ENTRIES))
960 		return;
961 
962 	/* Initialize RX ring */
963 	for (i = 0; i < priv->rx_q_entries; i++) {
964 		rxdes = &priv->rxdes[i];
965 		rxdes->rxdes0 = 0;
966 		rxdes->rxdes3 = cpu_to_le32(priv->rx_scratch_dma);
967 	}
968 	/* Mark the end of the ring */
969 	rxdes->rxdes0 |= cpu_to_le32(priv->rxdes0_edorr_mask);
970 
971 	if (WARN_ON(priv->tx_q_entries < MIN_RX_QUEUE_ENTRIES))
972 		return;
973 
974 	/* Initialize TX ring */
975 	for (i = 0; i < priv->tx_q_entries; i++) {
976 		txdes = &priv->txdes[i];
977 		txdes->txdes0 = 0;
978 	}
979 	txdes->txdes0 |= cpu_to_le32(priv->txdes0_edotr_mask);
980 }
981 
982 static int ftgmac100_alloc_rx_buffers(struct ftgmac100 *priv)
983 {
984 	int i;
985 
986 	for (i = 0; i < priv->rx_q_entries; i++) {
987 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
988 
989 		if (ftgmac100_alloc_rx_buf(priv, i, rxdes, GFP_KERNEL))
990 			return -ENOMEM;
991 	}
992 	return 0;
993 }
994 
995 static void ftgmac100_adjust_link(struct net_device *netdev)
996 {
997 	struct ftgmac100 *priv = netdev_priv(netdev);
998 	struct phy_device *phydev = netdev->phydev;
999 	bool tx_pause, rx_pause;
1000 	int new_speed;
1001 
1002 	/* We store "no link" as speed 0 */
1003 	if (!phydev->link)
1004 		new_speed = 0;
1005 	else
1006 		new_speed = phydev->speed;
1007 
1008 	/* Grab pause settings from PHY if configured to do so */
1009 	if (priv->aneg_pause) {
1010 		rx_pause = tx_pause = phydev->pause;
1011 		if (phydev->asym_pause)
1012 			tx_pause = !rx_pause;
1013 	} else {
1014 		rx_pause = priv->rx_pause;
1015 		tx_pause = priv->tx_pause;
1016 	}
1017 
1018 	/* Link hasn't changed, do nothing */
1019 	if (phydev->speed == priv->cur_speed &&
1020 	    phydev->duplex == priv->cur_duplex &&
1021 	    rx_pause == priv->rx_pause &&
1022 	    tx_pause == priv->tx_pause)
1023 		return;
1024 
1025 	/* Print status if we have a link or we had one and just lost it,
1026 	 * don't print otherwise.
1027 	 */
1028 	if (new_speed || priv->cur_speed)
1029 		phy_print_status(phydev);
1030 
1031 	priv->cur_speed = new_speed;
1032 	priv->cur_duplex = phydev->duplex;
1033 	priv->rx_pause = rx_pause;
1034 	priv->tx_pause = tx_pause;
1035 
1036 	/* Link is down, do nothing else */
1037 	if (!new_speed)
1038 		return;
1039 
1040 	/* Disable all interrupts */
1041 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1042 
1043 	/* Reset the adapter asynchronously */
1044 	schedule_work(&priv->reset_task);
1045 }
1046 
1047 static int ftgmac100_mii_probe(struct ftgmac100 *priv, phy_interface_t intf)
1048 {
1049 	struct net_device *netdev = priv->netdev;
1050 	struct phy_device *phydev;
1051 
1052 	phydev = phy_find_first(priv->mii_bus);
1053 	if (!phydev) {
1054 		netdev_info(netdev, "%s: no PHY found\n", netdev->name);
1055 		return -ENODEV;
1056 	}
1057 
1058 	phydev = phy_connect(netdev, phydev_name(phydev),
1059 			     &ftgmac100_adjust_link, intf);
1060 
1061 	if (IS_ERR(phydev)) {
1062 		netdev_err(netdev, "%s: Could not attach to PHY\n", netdev->name);
1063 		return PTR_ERR(phydev);
1064 	}
1065 
1066 	/* Indicate that we support PAUSE frames (see comment in
1067 	 * Documentation/networking/phy.rst)
1068 	 */
1069 	phy_support_asym_pause(phydev);
1070 
1071 	/* Display what we found */
1072 	phy_attached_info(phydev);
1073 
1074 	return 0;
1075 }
1076 
1077 static int ftgmac100_mdiobus_read(struct mii_bus *bus, int phy_addr, int regnum)
1078 {
1079 	struct net_device *netdev = bus->priv;
1080 	struct ftgmac100 *priv = netdev_priv(netdev);
1081 	unsigned int phycr;
1082 	int i;
1083 
1084 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1085 
1086 	/* preserve MDC cycle threshold */
1087 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1088 
1089 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1090 		 FTGMAC100_PHYCR_REGAD(regnum) |
1091 		 FTGMAC100_PHYCR_MIIRD;
1092 
1093 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1094 
1095 	for (i = 0; i < 10; i++) {
1096 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1097 
1098 		if ((phycr & FTGMAC100_PHYCR_MIIRD) == 0) {
1099 			int data;
1100 
1101 			data = ioread32(priv->base + FTGMAC100_OFFSET_PHYDATA);
1102 			return FTGMAC100_PHYDATA_MIIRDATA(data);
1103 		}
1104 
1105 		udelay(100);
1106 	}
1107 
1108 	netdev_err(netdev, "mdio read timed out\n");
1109 	return -EIO;
1110 }
1111 
1112 static int ftgmac100_mdiobus_write(struct mii_bus *bus, int phy_addr,
1113 				   int regnum, u16 value)
1114 {
1115 	struct net_device *netdev = bus->priv;
1116 	struct ftgmac100 *priv = netdev_priv(netdev);
1117 	unsigned int phycr;
1118 	int data;
1119 	int i;
1120 
1121 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1122 
1123 	/* preserve MDC cycle threshold */
1124 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1125 
1126 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1127 		 FTGMAC100_PHYCR_REGAD(regnum) |
1128 		 FTGMAC100_PHYCR_MIIWR;
1129 
1130 	data = FTGMAC100_PHYDATA_MIIWDATA(value);
1131 
1132 	iowrite32(data, priv->base + FTGMAC100_OFFSET_PHYDATA);
1133 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1134 
1135 	for (i = 0; i < 10; i++) {
1136 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1137 
1138 		if ((phycr & FTGMAC100_PHYCR_MIIWR) == 0)
1139 			return 0;
1140 
1141 		udelay(100);
1142 	}
1143 
1144 	netdev_err(netdev, "mdio write timed out\n");
1145 	return -EIO;
1146 }
1147 
1148 static void ftgmac100_get_drvinfo(struct net_device *netdev,
1149 				  struct ethtool_drvinfo *info)
1150 {
1151 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1152 	strlcpy(info->bus_info, dev_name(&netdev->dev), sizeof(info->bus_info));
1153 }
1154 
1155 static void ftgmac100_get_ringparam(struct net_device *netdev,
1156 				    struct ethtool_ringparam *ering)
1157 {
1158 	struct ftgmac100 *priv = netdev_priv(netdev);
1159 
1160 	memset(ering, 0, sizeof(*ering));
1161 	ering->rx_max_pending = MAX_RX_QUEUE_ENTRIES;
1162 	ering->tx_max_pending = MAX_TX_QUEUE_ENTRIES;
1163 	ering->rx_pending = priv->rx_q_entries;
1164 	ering->tx_pending = priv->tx_q_entries;
1165 }
1166 
1167 static int ftgmac100_set_ringparam(struct net_device *netdev,
1168 				   struct ethtool_ringparam *ering)
1169 {
1170 	struct ftgmac100 *priv = netdev_priv(netdev);
1171 
1172 	if (ering->rx_pending > MAX_RX_QUEUE_ENTRIES ||
1173 	    ering->tx_pending > MAX_TX_QUEUE_ENTRIES ||
1174 	    ering->rx_pending < MIN_RX_QUEUE_ENTRIES ||
1175 	    ering->tx_pending < MIN_TX_QUEUE_ENTRIES ||
1176 	    !is_power_of_2(ering->rx_pending) ||
1177 	    !is_power_of_2(ering->tx_pending))
1178 		return -EINVAL;
1179 
1180 	priv->new_rx_q_entries = ering->rx_pending;
1181 	priv->new_tx_q_entries = ering->tx_pending;
1182 	if (netif_running(netdev))
1183 		schedule_work(&priv->reset_task);
1184 
1185 	return 0;
1186 }
1187 
1188 static void ftgmac100_get_pauseparam(struct net_device *netdev,
1189 				     struct ethtool_pauseparam *pause)
1190 {
1191 	struct ftgmac100 *priv = netdev_priv(netdev);
1192 
1193 	pause->autoneg = priv->aneg_pause;
1194 	pause->tx_pause = priv->tx_pause;
1195 	pause->rx_pause = priv->rx_pause;
1196 }
1197 
1198 static int ftgmac100_set_pauseparam(struct net_device *netdev,
1199 				    struct ethtool_pauseparam *pause)
1200 {
1201 	struct ftgmac100 *priv = netdev_priv(netdev);
1202 	struct phy_device *phydev = netdev->phydev;
1203 
1204 	priv->aneg_pause = pause->autoneg;
1205 	priv->tx_pause = pause->tx_pause;
1206 	priv->rx_pause = pause->rx_pause;
1207 
1208 	if (phydev)
1209 		phy_set_asym_pause(phydev, pause->rx_pause, pause->tx_pause);
1210 
1211 	if (netif_running(netdev)) {
1212 		if (!(phydev && priv->aneg_pause))
1213 			ftgmac100_config_pause(priv);
1214 	}
1215 
1216 	return 0;
1217 }
1218 
1219 static const struct ethtool_ops ftgmac100_ethtool_ops = {
1220 	.get_drvinfo		= ftgmac100_get_drvinfo,
1221 	.get_link		= ethtool_op_get_link,
1222 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1223 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1224 	.nway_reset		= phy_ethtool_nway_reset,
1225 	.get_ringparam		= ftgmac100_get_ringparam,
1226 	.set_ringparam		= ftgmac100_set_ringparam,
1227 	.get_pauseparam		= ftgmac100_get_pauseparam,
1228 	.set_pauseparam		= ftgmac100_set_pauseparam,
1229 };
1230 
1231 static irqreturn_t ftgmac100_interrupt(int irq, void *dev_id)
1232 {
1233 	struct net_device *netdev = dev_id;
1234 	struct ftgmac100 *priv = netdev_priv(netdev);
1235 	unsigned int status, new_mask = FTGMAC100_INT_BAD;
1236 
1237 	/* Fetch and clear interrupt bits, process abnormal ones */
1238 	status = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
1239 	iowrite32(status, priv->base + FTGMAC100_OFFSET_ISR);
1240 	if (unlikely(status & FTGMAC100_INT_BAD)) {
1241 
1242 		/* RX buffer unavailable */
1243 		if (status & FTGMAC100_INT_NO_RXBUF)
1244 			netdev->stats.rx_over_errors++;
1245 
1246 		/* received packet lost due to RX FIFO full */
1247 		if (status & FTGMAC100_INT_RPKT_LOST)
1248 			netdev->stats.rx_fifo_errors++;
1249 
1250 		/* sent packet lost due to excessive TX collision */
1251 		if (status & FTGMAC100_INT_XPKT_LOST)
1252 			netdev->stats.tx_fifo_errors++;
1253 
1254 		/* AHB error -> Reset the chip */
1255 		if (status & FTGMAC100_INT_AHB_ERR) {
1256 			if (net_ratelimit())
1257 				netdev_warn(netdev,
1258 					   "AHB bus error ! Resetting chip.\n");
1259 			iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1260 			schedule_work(&priv->reset_task);
1261 			return IRQ_HANDLED;
1262 		}
1263 
1264 		/* We may need to restart the MAC after such errors, delay
1265 		 * this until after we have freed some Rx buffers though
1266 		 */
1267 		priv->need_mac_restart = true;
1268 
1269 		/* Disable those errors until we restart */
1270 		new_mask &= ~status;
1271 	}
1272 
1273 	/* Only enable "bad" interrupts while NAPI is on */
1274 	iowrite32(new_mask, priv->base + FTGMAC100_OFFSET_IER);
1275 
1276 	/* Schedule NAPI bh */
1277 	napi_schedule_irqoff(&priv->napi);
1278 
1279 	return IRQ_HANDLED;
1280 }
1281 
1282 static bool ftgmac100_check_rx(struct ftgmac100 *priv)
1283 {
1284 	struct ftgmac100_rxdes *rxdes = &priv->rxdes[priv->rx_pointer];
1285 
1286 	/* Do we have a packet ? */
1287 	return !!(rxdes->rxdes0 & cpu_to_le32(FTGMAC100_RXDES0_RXPKT_RDY));
1288 }
1289 
1290 static int ftgmac100_poll(struct napi_struct *napi, int budget)
1291 {
1292 	struct ftgmac100 *priv = container_of(napi, struct ftgmac100, napi);
1293 	int work_done = 0;
1294 	bool more;
1295 
1296 	/* Handle TX completions */
1297 	if (ftgmac100_tx_buf_cleanable(priv))
1298 		ftgmac100_tx_complete(priv);
1299 
1300 	/* Handle RX packets */
1301 	do {
1302 		more = ftgmac100_rx_packet(priv, &work_done);
1303 	} while (more && work_done < budget);
1304 
1305 
1306 	/* The interrupt is telling us to kick the MAC back to life
1307 	 * after an RX overflow
1308 	 */
1309 	if (unlikely(priv->need_mac_restart)) {
1310 		ftgmac100_start_hw(priv);
1311 
1312 		/* Re-enable "bad" interrupts */
1313 		iowrite32(FTGMAC100_INT_BAD,
1314 			  priv->base + FTGMAC100_OFFSET_IER);
1315 	}
1316 
1317 	/* As long as we are waiting for transmit packets to be
1318 	 * completed we keep NAPI going
1319 	 */
1320 	if (ftgmac100_tx_buf_cleanable(priv))
1321 		work_done = budget;
1322 
1323 	if (work_done < budget) {
1324 		/* We are about to re-enable all interrupts. However
1325 		 * the HW has been latching RX/TX packet interrupts while
1326 		 * they were masked. So we clear them first, then we need
1327 		 * to re-check if there's something to process
1328 		 */
1329 		iowrite32(FTGMAC100_INT_RXTX,
1330 			  priv->base + FTGMAC100_OFFSET_ISR);
1331 
1332 		/* Push the above (and provides a barrier vs. subsequent
1333 		 * reads of the descriptor).
1334 		 */
1335 		ioread32(priv->base + FTGMAC100_OFFSET_ISR);
1336 
1337 		/* Check RX and TX descriptors for more work to do */
1338 		if (ftgmac100_check_rx(priv) ||
1339 		    ftgmac100_tx_buf_cleanable(priv))
1340 			return budget;
1341 
1342 		/* deschedule NAPI */
1343 		napi_complete(napi);
1344 
1345 		/* enable all interrupts */
1346 		iowrite32(FTGMAC100_INT_ALL,
1347 			  priv->base + FTGMAC100_OFFSET_IER);
1348 	}
1349 
1350 	return work_done;
1351 }
1352 
1353 static int ftgmac100_init_all(struct ftgmac100 *priv, bool ignore_alloc_err)
1354 {
1355 	int err = 0;
1356 
1357 	/* Re-init descriptors (adjust queue sizes) */
1358 	ftgmac100_init_rings(priv);
1359 
1360 	/* Realloc rx descriptors */
1361 	err = ftgmac100_alloc_rx_buffers(priv);
1362 	if (err && !ignore_alloc_err)
1363 		return err;
1364 
1365 	/* Reinit and restart HW */
1366 	ftgmac100_init_hw(priv);
1367 	ftgmac100_config_pause(priv);
1368 	ftgmac100_start_hw(priv);
1369 
1370 	/* Re-enable the device */
1371 	napi_enable(&priv->napi);
1372 	netif_start_queue(priv->netdev);
1373 
1374 	/* Enable all interrupts */
1375 	iowrite32(FTGMAC100_INT_ALL, priv->base + FTGMAC100_OFFSET_IER);
1376 
1377 	return err;
1378 }
1379 
1380 static void ftgmac100_reset_task(struct work_struct *work)
1381 {
1382 	struct ftgmac100 *priv = container_of(work, struct ftgmac100,
1383 					      reset_task);
1384 	struct net_device *netdev = priv->netdev;
1385 	int err;
1386 
1387 	netdev_dbg(netdev, "Resetting NIC...\n");
1388 
1389 	/* Lock the world */
1390 	rtnl_lock();
1391 	if (netdev->phydev)
1392 		mutex_lock(&netdev->phydev->lock);
1393 	if (priv->mii_bus)
1394 		mutex_lock(&priv->mii_bus->mdio_lock);
1395 
1396 
1397 	/* Check if the interface is still up */
1398 	if (!netif_running(netdev))
1399 		goto bail;
1400 
1401 	/* Stop the network stack */
1402 	netif_trans_update(netdev);
1403 	napi_disable(&priv->napi);
1404 	netif_tx_disable(netdev);
1405 
1406 	/* Stop and reset the MAC */
1407 	ftgmac100_stop_hw(priv);
1408 	err = ftgmac100_reset_and_config_mac(priv);
1409 	if (err) {
1410 		/* Not much we can do ... it might come back... */
1411 		netdev_err(netdev, "attempting to continue...\n");
1412 	}
1413 
1414 	/* Free all rx and tx buffers */
1415 	ftgmac100_free_buffers(priv);
1416 
1417 	/* Setup everything again and restart chip */
1418 	ftgmac100_init_all(priv, true);
1419 
1420 	netdev_dbg(netdev, "Reset done !\n");
1421  bail:
1422 	if (priv->mii_bus)
1423 		mutex_unlock(&priv->mii_bus->mdio_lock);
1424 	if (netdev->phydev)
1425 		mutex_unlock(&netdev->phydev->lock);
1426 	rtnl_unlock();
1427 }
1428 
1429 static int ftgmac100_open(struct net_device *netdev)
1430 {
1431 	struct ftgmac100 *priv = netdev_priv(netdev);
1432 	int err;
1433 
1434 	/* Allocate ring buffers  */
1435 	err = ftgmac100_alloc_rings(priv);
1436 	if (err) {
1437 		netdev_err(netdev, "Failed to allocate descriptors\n");
1438 		return err;
1439 	}
1440 
1441 	/* When using NC-SI we force the speed to 100Mbit/s full duplex,
1442 	 *
1443 	 * Otherwise we leave it set to 0 (no link), the link
1444 	 * message from the PHY layer will handle setting it up to
1445 	 * something else if needed.
1446 	 */
1447 	if (priv->use_ncsi) {
1448 		priv->cur_duplex = DUPLEX_FULL;
1449 		priv->cur_speed = SPEED_100;
1450 	} else {
1451 		priv->cur_duplex = 0;
1452 		priv->cur_speed = 0;
1453 	}
1454 
1455 	/* Reset the hardware */
1456 	err = ftgmac100_reset_and_config_mac(priv);
1457 	if (err)
1458 		goto err_hw;
1459 
1460 	/* Initialize NAPI */
1461 	netif_napi_add(netdev, &priv->napi, ftgmac100_poll, 64);
1462 
1463 	/* Grab our interrupt */
1464 	err = request_irq(netdev->irq, ftgmac100_interrupt, 0, netdev->name, netdev);
1465 	if (err) {
1466 		netdev_err(netdev, "failed to request irq %d\n", netdev->irq);
1467 		goto err_irq;
1468 	}
1469 
1470 	/* Start things up */
1471 	err = ftgmac100_init_all(priv, false);
1472 	if (err) {
1473 		netdev_err(netdev, "Failed to allocate packet buffers\n");
1474 		goto err_alloc;
1475 	}
1476 
1477 	if (netdev->phydev) {
1478 		/* If we have a PHY, start polling */
1479 		phy_start(netdev->phydev);
1480 	} else if (priv->use_ncsi) {
1481 		/* If using NC-SI, set our carrier on and start the stack */
1482 		netif_carrier_on(netdev);
1483 
1484 		/* Start the NCSI device */
1485 		err = ncsi_start_dev(priv->ndev);
1486 		if (err)
1487 			goto err_ncsi;
1488 	}
1489 
1490 	return 0;
1491 
1492  err_ncsi:
1493 	napi_disable(&priv->napi);
1494 	netif_stop_queue(netdev);
1495  err_alloc:
1496 	ftgmac100_free_buffers(priv);
1497 	free_irq(netdev->irq, netdev);
1498  err_irq:
1499 	netif_napi_del(&priv->napi);
1500  err_hw:
1501 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1502 	ftgmac100_free_rings(priv);
1503 	return err;
1504 }
1505 
1506 static int ftgmac100_stop(struct net_device *netdev)
1507 {
1508 	struct ftgmac100 *priv = netdev_priv(netdev);
1509 
1510 	/* Note about the reset task: We are called with the rtnl lock
1511 	 * held, so we are synchronized against the core of the reset
1512 	 * task. We must not try to synchronously cancel it otherwise
1513 	 * we can deadlock. But since it will test for netif_running()
1514 	 * which has already been cleared by the net core, we don't
1515 	 * anything special to do.
1516 	 */
1517 
1518 	/* disable all interrupts */
1519 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1520 
1521 	netif_stop_queue(netdev);
1522 	napi_disable(&priv->napi);
1523 	netif_napi_del(&priv->napi);
1524 	if (netdev->phydev)
1525 		phy_stop(netdev->phydev);
1526 	else if (priv->use_ncsi)
1527 		ncsi_stop_dev(priv->ndev);
1528 
1529 	ftgmac100_stop_hw(priv);
1530 	free_irq(netdev->irq, netdev);
1531 	ftgmac100_free_buffers(priv);
1532 	ftgmac100_free_rings(priv);
1533 
1534 	return 0;
1535 }
1536 
1537 static void ftgmac100_tx_timeout(struct net_device *netdev, unsigned int txqueue)
1538 {
1539 	struct ftgmac100 *priv = netdev_priv(netdev);
1540 
1541 	/* Disable all interrupts */
1542 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1543 
1544 	/* Do the reset outside of interrupt context */
1545 	schedule_work(&priv->reset_task);
1546 }
1547 
1548 static int ftgmac100_set_features(struct net_device *netdev,
1549 				  netdev_features_t features)
1550 {
1551 	struct ftgmac100 *priv = netdev_priv(netdev);
1552 	netdev_features_t changed = netdev->features ^ features;
1553 
1554 	if (!netif_running(netdev))
1555 		return 0;
1556 
1557 	/* Update the vlan filtering bit */
1558 	if (changed & NETIF_F_HW_VLAN_CTAG_RX) {
1559 		u32 maccr;
1560 
1561 		maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
1562 		if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
1563 			maccr |= FTGMAC100_MACCR_RM_VLAN;
1564 		else
1565 			maccr &= ~FTGMAC100_MACCR_RM_VLAN;
1566 		iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
1567 	}
1568 
1569 	return 0;
1570 }
1571 
1572 #ifdef CONFIG_NET_POLL_CONTROLLER
1573 static void ftgmac100_poll_controller(struct net_device *netdev)
1574 {
1575 	unsigned long flags;
1576 
1577 	local_irq_save(flags);
1578 	ftgmac100_interrupt(netdev->irq, netdev);
1579 	local_irq_restore(flags);
1580 }
1581 #endif
1582 
1583 static const struct net_device_ops ftgmac100_netdev_ops = {
1584 	.ndo_open		= ftgmac100_open,
1585 	.ndo_stop		= ftgmac100_stop,
1586 	.ndo_start_xmit		= ftgmac100_hard_start_xmit,
1587 	.ndo_set_mac_address	= ftgmac100_set_mac_addr,
1588 	.ndo_validate_addr	= eth_validate_addr,
1589 	.ndo_do_ioctl		= phy_do_ioctl,
1590 	.ndo_tx_timeout		= ftgmac100_tx_timeout,
1591 	.ndo_set_rx_mode	= ftgmac100_set_rx_mode,
1592 	.ndo_set_features	= ftgmac100_set_features,
1593 #ifdef CONFIG_NET_POLL_CONTROLLER
1594 	.ndo_poll_controller	= ftgmac100_poll_controller,
1595 #endif
1596 	.ndo_vlan_rx_add_vid	= ncsi_vlan_rx_add_vid,
1597 	.ndo_vlan_rx_kill_vid	= ncsi_vlan_rx_kill_vid,
1598 };
1599 
1600 static int ftgmac100_setup_mdio(struct net_device *netdev)
1601 {
1602 	struct ftgmac100 *priv = netdev_priv(netdev);
1603 	struct platform_device *pdev = to_platform_device(priv->dev);
1604 	phy_interface_t phy_intf = PHY_INTERFACE_MODE_RGMII;
1605 	struct device_node *np = pdev->dev.of_node;
1606 	int i, err = 0;
1607 	u32 reg;
1608 
1609 	/* initialize mdio bus */
1610 	priv->mii_bus = mdiobus_alloc();
1611 	if (!priv->mii_bus)
1612 		return -EIO;
1613 
1614 	if (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
1615 	    of_device_is_compatible(np, "aspeed,ast2500-mac")) {
1616 		/* The AST2600 has a separate MDIO controller */
1617 
1618 		/* For the AST2400 and AST2500 this driver only supports the
1619 		 * old MDIO interface
1620 		 */
1621 		reg = ioread32(priv->base + FTGMAC100_OFFSET_REVR);
1622 		reg &= ~FTGMAC100_REVR_NEW_MDIO_INTERFACE;
1623 		iowrite32(reg, priv->base + FTGMAC100_OFFSET_REVR);
1624 	}
1625 
1626 	/* Get PHY mode from device-tree */
1627 	if (np) {
1628 		/* Default to RGMII. It's a gigabit part after all */
1629 		err = of_get_phy_mode(np, &phy_intf);
1630 		if (err)
1631 			phy_intf = PHY_INTERFACE_MODE_RGMII;
1632 
1633 		/* Aspeed only supports these. I don't know about other IP
1634 		 * block vendors so I'm going to just let them through for
1635 		 * now. Note that this is only a warning if for some obscure
1636 		 * reason the DT really means to lie about it or it's a newer
1637 		 * part we don't know about.
1638 		 *
1639 		 * On the Aspeed SoC there are additionally straps and SCU
1640 		 * control bits that could tell us what the interface is
1641 		 * (or allow us to configure it while the IP block is held
1642 		 * in reset). For now I chose to keep this driver away from
1643 		 * those SoC specific bits and assume the device-tree is
1644 		 * right and the SCU has been configured properly by pinmux
1645 		 * or the firmware.
1646 		 */
1647 		if (priv->is_aspeed &&
1648 		    phy_intf != PHY_INTERFACE_MODE_RMII &&
1649 		    phy_intf != PHY_INTERFACE_MODE_RGMII &&
1650 		    phy_intf != PHY_INTERFACE_MODE_RGMII_ID &&
1651 		    phy_intf != PHY_INTERFACE_MODE_RGMII_RXID &&
1652 		    phy_intf != PHY_INTERFACE_MODE_RGMII_TXID) {
1653 			netdev_warn(netdev,
1654 				   "Unsupported PHY mode %s !\n",
1655 				   phy_modes(phy_intf));
1656 		}
1657 	}
1658 
1659 	priv->mii_bus->name = "ftgmac100_mdio";
1660 	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%d",
1661 		 pdev->name, pdev->id);
1662 	priv->mii_bus->parent = priv->dev;
1663 	priv->mii_bus->priv = priv->netdev;
1664 	priv->mii_bus->read = ftgmac100_mdiobus_read;
1665 	priv->mii_bus->write = ftgmac100_mdiobus_write;
1666 
1667 	for (i = 0; i < PHY_MAX_ADDR; i++)
1668 		priv->mii_bus->irq[i] = PHY_POLL;
1669 
1670 	err = mdiobus_register(priv->mii_bus);
1671 	if (err) {
1672 		dev_err(priv->dev, "Cannot register MDIO bus!\n");
1673 		goto err_register_mdiobus;
1674 	}
1675 
1676 	err = ftgmac100_mii_probe(priv, phy_intf);
1677 	if (err) {
1678 		dev_err(priv->dev, "MII Probe failed!\n");
1679 		goto err_mii_probe;
1680 	}
1681 
1682 	return 0;
1683 
1684 err_mii_probe:
1685 	mdiobus_unregister(priv->mii_bus);
1686 err_register_mdiobus:
1687 	mdiobus_free(priv->mii_bus);
1688 	return err;
1689 }
1690 
1691 static void ftgmac100_destroy_mdio(struct net_device *netdev)
1692 {
1693 	struct ftgmac100 *priv = netdev_priv(netdev);
1694 
1695 	if (!netdev->phydev)
1696 		return;
1697 
1698 	phy_disconnect(netdev->phydev);
1699 	mdiobus_unregister(priv->mii_bus);
1700 	mdiobus_free(priv->mii_bus);
1701 }
1702 
1703 static void ftgmac100_ncsi_handler(struct ncsi_dev *nd)
1704 {
1705 	if (unlikely(nd->state != ncsi_dev_state_functional))
1706 		return;
1707 
1708 	netdev_dbg(nd->dev, "NCSI interface %s\n",
1709 		   nd->link_up ? "up" : "down");
1710 }
1711 
1712 static int ftgmac100_setup_clk(struct ftgmac100 *priv)
1713 {
1714 	struct clk *clk;
1715 	int rc;
1716 
1717 	clk = devm_clk_get(priv->dev, NULL /* MACCLK */);
1718 	if (IS_ERR(clk))
1719 		return PTR_ERR(clk);
1720 	priv->clk = clk;
1721 	rc = clk_prepare_enable(priv->clk);
1722 	if (rc)
1723 		return rc;
1724 
1725 	/* Aspeed specifies a 100MHz clock is required for up to
1726 	 * 1000Mbit link speeds. As NCSI is limited to 100Mbit, 25MHz
1727 	 * is sufficient
1728 	 */
1729 	rc = clk_set_rate(priv->clk, priv->use_ncsi ? FTGMAC_25MHZ :
1730 			  FTGMAC_100MHZ);
1731 	if (rc)
1732 		goto cleanup_clk;
1733 
1734 	/* RCLK is for RMII, typically used for NCSI. Optional because it's not
1735 	 * necessary if it's the AST2400 MAC, or the MAC is configured for
1736 	 * RGMII, or the controller is not an ASPEED-based controller.
1737 	 */
1738 	priv->rclk = devm_clk_get_optional(priv->dev, "RCLK");
1739 	rc = clk_prepare_enable(priv->rclk);
1740 	if (!rc)
1741 		return 0;
1742 
1743 cleanup_clk:
1744 	clk_disable_unprepare(priv->clk);
1745 
1746 	return rc;
1747 }
1748 
1749 static int ftgmac100_probe(struct platform_device *pdev)
1750 {
1751 	struct resource *res;
1752 	int irq;
1753 	struct net_device *netdev;
1754 	struct ftgmac100 *priv;
1755 	struct device_node *np;
1756 	int err = 0;
1757 
1758 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1759 	if (!res)
1760 		return -ENXIO;
1761 
1762 	irq = platform_get_irq(pdev, 0);
1763 	if (irq < 0)
1764 		return irq;
1765 
1766 	/* setup net_device */
1767 	netdev = alloc_etherdev(sizeof(*priv));
1768 	if (!netdev) {
1769 		err = -ENOMEM;
1770 		goto err_alloc_etherdev;
1771 	}
1772 
1773 	SET_NETDEV_DEV(netdev, &pdev->dev);
1774 
1775 	netdev->ethtool_ops = &ftgmac100_ethtool_ops;
1776 	netdev->netdev_ops = &ftgmac100_netdev_ops;
1777 	netdev->watchdog_timeo = 5 * HZ;
1778 
1779 	platform_set_drvdata(pdev, netdev);
1780 
1781 	/* setup private data */
1782 	priv = netdev_priv(netdev);
1783 	priv->netdev = netdev;
1784 	priv->dev = &pdev->dev;
1785 	INIT_WORK(&priv->reset_task, ftgmac100_reset_task);
1786 
1787 	/* map io memory */
1788 	priv->res = request_mem_region(res->start, resource_size(res),
1789 				       dev_name(&pdev->dev));
1790 	if (!priv->res) {
1791 		dev_err(&pdev->dev, "Could not reserve memory region\n");
1792 		err = -ENOMEM;
1793 		goto err_req_mem;
1794 	}
1795 
1796 	priv->base = ioremap(res->start, resource_size(res));
1797 	if (!priv->base) {
1798 		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1799 		err = -EIO;
1800 		goto err_ioremap;
1801 	}
1802 
1803 	netdev->irq = irq;
1804 
1805 	/* Enable pause */
1806 	priv->tx_pause = true;
1807 	priv->rx_pause = true;
1808 	priv->aneg_pause = true;
1809 
1810 	/* MAC address from chip or random one */
1811 	ftgmac100_initial_mac(priv);
1812 
1813 	np = pdev->dev.of_node;
1814 	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
1815 		   of_device_is_compatible(np, "aspeed,ast2500-mac") ||
1816 		   of_device_is_compatible(np, "aspeed,ast2600-mac"))) {
1817 		priv->rxdes0_edorr_mask = BIT(30);
1818 		priv->txdes0_edotr_mask = BIT(30);
1819 		priv->is_aspeed = true;
1820 		/* Disable ast2600 problematic HW arbitration */
1821 		if (of_device_is_compatible(np, "aspeed,ast2600-mac")) {
1822 			iowrite32(FTGMAC100_TM_DEFAULT,
1823 				  priv->base + FTGMAC100_OFFSET_TM);
1824 		}
1825 	} else {
1826 		priv->rxdes0_edorr_mask = BIT(15);
1827 		priv->txdes0_edotr_mask = BIT(15);
1828 	}
1829 
1830 	if (np && of_get_property(np, "use-ncsi", NULL)) {
1831 		if (!IS_ENABLED(CONFIG_NET_NCSI)) {
1832 			dev_err(&pdev->dev, "NCSI stack not enabled\n");
1833 			goto err_ncsi_dev;
1834 		}
1835 
1836 		dev_info(&pdev->dev, "Using NCSI interface\n");
1837 		priv->use_ncsi = true;
1838 		priv->ndev = ncsi_register_dev(netdev, ftgmac100_ncsi_handler);
1839 		if (!priv->ndev)
1840 			goto err_ncsi_dev;
1841 	} else if (np && of_get_property(np, "phy-handle", NULL)) {
1842 		struct phy_device *phy;
1843 
1844 		phy = of_phy_get_and_connect(priv->netdev, np,
1845 					     &ftgmac100_adjust_link);
1846 		if (!phy) {
1847 			dev_err(&pdev->dev, "Failed to connect to phy\n");
1848 			goto err_setup_mdio;
1849 		}
1850 
1851 		/* Indicate that we support PAUSE frames (see comment in
1852 		 * Documentation/networking/phy.rst)
1853 		 */
1854 		phy_support_asym_pause(phy);
1855 
1856 		/* Display what we found */
1857 		phy_attached_info(phy);
1858 	} else if (np && !of_get_child_by_name(np, "mdio")) {
1859 		/* Support legacy ASPEED devicetree descriptions that decribe a
1860 		 * MAC with an embedded MDIO controller but have no "mdio"
1861 		 * child node. Automatically scan the MDIO bus for available
1862 		 * PHYs.
1863 		 */
1864 		priv->use_ncsi = false;
1865 		err = ftgmac100_setup_mdio(netdev);
1866 		if (err)
1867 			goto err_setup_mdio;
1868 	}
1869 
1870 	if (priv->is_aspeed) {
1871 		err = ftgmac100_setup_clk(priv);
1872 		if (err)
1873 			goto err_ncsi_dev;
1874 	}
1875 
1876 	/* Default ring sizes */
1877 	priv->rx_q_entries = priv->new_rx_q_entries = DEF_RX_QUEUE_ENTRIES;
1878 	priv->tx_q_entries = priv->new_tx_q_entries = DEF_TX_QUEUE_ENTRIES;
1879 
1880 	/* Base feature set */
1881 	netdev->hw_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM |
1882 		NETIF_F_GRO | NETIF_F_SG | NETIF_F_HW_VLAN_CTAG_RX |
1883 		NETIF_F_HW_VLAN_CTAG_TX;
1884 
1885 	if (priv->use_ncsi)
1886 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1887 
1888 	/* AST2400  doesn't have working HW checksum generation */
1889 	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac")))
1890 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
1891 	if (np && of_get_property(np, "no-hw-checksum", NULL))
1892 		netdev->hw_features &= ~(NETIF_F_HW_CSUM | NETIF_F_RXCSUM);
1893 	netdev->features |= netdev->hw_features;
1894 
1895 	/* register network device */
1896 	err = register_netdev(netdev);
1897 	if (err) {
1898 		dev_err(&pdev->dev, "Failed to register netdev\n");
1899 		goto err_register_netdev;
1900 	}
1901 
1902 	netdev_info(netdev, "irq %d, mapped at %p\n", netdev->irq, priv->base);
1903 
1904 	return 0;
1905 
1906 err_register_netdev:
1907 	clk_disable_unprepare(priv->rclk);
1908 	clk_disable_unprepare(priv->clk);
1909 err_ncsi_dev:
1910 	ftgmac100_destroy_mdio(netdev);
1911 err_setup_mdio:
1912 	iounmap(priv->base);
1913 err_ioremap:
1914 	release_resource(priv->res);
1915 err_req_mem:
1916 	free_netdev(netdev);
1917 err_alloc_etherdev:
1918 	return err;
1919 }
1920 
1921 static int ftgmac100_remove(struct platform_device *pdev)
1922 {
1923 	struct net_device *netdev;
1924 	struct ftgmac100 *priv;
1925 
1926 	netdev = platform_get_drvdata(pdev);
1927 	priv = netdev_priv(netdev);
1928 
1929 	unregister_netdev(netdev);
1930 
1931 	clk_disable_unprepare(priv->rclk);
1932 	clk_disable_unprepare(priv->clk);
1933 
1934 	/* There's a small chance the reset task will have been re-queued,
1935 	 * during stop, make sure it's gone before we free the structure.
1936 	 */
1937 	cancel_work_sync(&priv->reset_task);
1938 
1939 	ftgmac100_destroy_mdio(netdev);
1940 
1941 	iounmap(priv->base);
1942 	release_resource(priv->res);
1943 
1944 	netif_napi_del(&priv->napi);
1945 	free_netdev(netdev);
1946 	return 0;
1947 }
1948 
1949 static const struct of_device_id ftgmac100_of_match[] = {
1950 	{ .compatible = "faraday,ftgmac100" },
1951 	{ }
1952 };
1953 MODULE_DEVICE_TABLE(of, ftgmac100_of_match);
1954 
1955 static struct platform_driver ftgmac100_driver = {
1956 	.probe	= ftgmac100_probe,
1957 	.remove	= ftgmac100_remove,
1958 	.driver	= {
1959 		.name		= DRV_NAME,
1960 		.of_match_table	= ftgmac100_of_match,
1961 	},
1962 };
1963 module_platform_driver(ftgmac100_driver);
1964 
1965 MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
1966 MODULE_DESCRIPTION("FTGMAC100 driver");
1967 MODULE_LICENSE("GPL");
1968