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 #define DRV_VERSION	"0.7"
34 
35 /* Arbitrary values, I am not sure the HW has limits */
36 #define MAX_RX_QUEUE_ENTRIES	1024
37 #define MAX_TX_QUEUE_ENTRIES	1024
38 #define MIN_RX_QUEUE_ENTRIES	32
39 #define MIN_TX_QUEUE_ENTRIES	32
40 
41 /* Defaults */
42 #define DEF_RX_QUEUE_ENTRIES	128
43 #define DEF_TX_QUEUE_ENTRIES	128
44 
45 #define MAX_PKT_SIZE		1536
46 #define RX_BUF_SIZE		MAX_PKT_SIZE	/* must be smaller than 0x3fff */
47 
48 /* Min number of tx ring entries before stopping queue */
49 #define TX_THRESHOLD		(MAX_SKB_FRAGS + 1)
50 
51 #define FTGMAC_100MHZ		100000000
52 #define FTGMAC_25MHZ		25000000
53 
54 struct ftgmac100 {
55 	/* Registers */
56 	struct resource *res;
57 	void __iomem *base;
58 
59 	/* Rx ring */
60 	unsigned int rx_q_entries;
61 	struct ftgmac100_rxdes *rxdes;
62 	dma_addr_t rxdes_dma;
63 	struct sk_buff **rx_skbs;
64 	unsigned int rx_pointer;
65 	u32 rxdes0_edorr_mask;
66 
67 	/* Tx ring */
68 	unsigned int tx_q_entries;
69 	struct ftgmac100_txdes *txdes;
70 	dma_addr_t txdes_dma;
71 	struct sk_buff **tx_skbs;
72 	unsigned int tx_clean_pointer;
73 	unsigned int tx_pointer;
74 	u32 txdes0_edotr_mask;
75 
76 	/* Used to signal the reset task of ring change request */
77 	unsigned int new_rx_q_entries;
78 	unsigned int new_tx_q_entries;
79 
80 	/* Scratch page to use when rx skb alloc fails */
81 	void *rx_scratch;
82 	dma_addr_t rx_scratch_dma;
83 
84 	/* Component structures */
85 	struct net_device *netdev;
86 	struct device *dev;
87 	struct ncsi_dev *ndev;
88 	struct napi_struct napi;
89 	struct work_struct reset_task;
90 	struct mii_bus *mii_bus;
91 	struct clk *clk;
92 
93 	/* Link management */
94 	int cur_speed;
95 	int cur_duplex;
96 	bool use_ncsi;
97 
98 	/* Multicast filter settings */
99 	u32 maht0;
100 	u32 maht1;
101 
102 	/* Flow control settings */
103 	bool tx_pause;
104 	bool rx_pause;
105 	bool aneg_pause;
106 
107 	/* Misc */
108 	bool need_mac_restart;
109 	bool is_aspeed;
110 };
111 
112 static int ftgmac100_reset_mac(struct ftgmac100 *priv, u32 maccr)
113 {
114 	struct net_device *netdev = priv->netdev;
115 	int i;
116 
117 	/* NOTE: reset clears all registers */
118 	iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
119 	iowrite32(maccr | FTGMAC100_MACCR_SW_RST,
120 		  priv->base + FTGMAC100_OFFSET_MACCR);
121 	for (i = 0; i < 200; i++) {
122 		unsigned int maccr;
123 
124 		maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
125 		if (!(maccr & FTGMAC100_MACCR_SW_RST))
126 			return 0;
127 
128 		udelay(1);
129 	}
130 
131 	netdev_err(netdev, "Hardware reset failed\n");
132 	return -EIO;
133 }
134 
135 static int ftgmac100_reset_and_config_mac(struct ftgmac100 *priv)
136 {
137 	u32 maccr = 0;
138 
139 	switch (priv->cur_speed) {
140 	case SPEED_10:
141 	case 0: /* no link */
142 		break;
143 
144 	case SPEED_100:
145 		maccr |= FTGMAC100_MACCR_FAST_MODE;
146 		break;
147 
148 	case SPEED_1000:
149 		maccr |= FTGMAC100_MACCR_GIGA_MODE;
150 		break;
151 	default:
152 		netdev_err(priv->netdev, "Unknown speed %d !\n",
153 			   priv->cur_speed);
154 		break;
155 	}
156 
157 	/* (Re)initialize the queue pointers */
158 	priv->rx_pointer = 0;
159 	priv->tx_clean_pointer = 0;
160 	priv->tx_pointer = 0;
161 
162 	/* The doc says reset twice with 10us interval */
163 	if (ftgmac100_reset_mac(priv, maccr))
164 		return -EIO;
165 	usleep_range(10, 1000);
166 	return ftgmac100_reset_mac(priv, maccr);
167 }
168 
169 static void ftgmac100_write_mac_addr(struct ftgmac100 *priv, const u8 *mac)
170 {
171 	unsigned int maddr = mac[0] << 8 | mac[1];
172 	unsigned int laddr = mac[2] << 24 | mac[3] << 16 | mac[4] << 8 | mac[5];
173 
174 	iowrite32(maddr, priv->base + FTGMAC100_OFFSET_MAC_MADR);
175 	iowrite32(laddr, priv->base + FTGMAC100_OFFSET_MAC_LADR);
176 }
177 
178 static void ftgmac100_initial_mac(struct ftgmac100 *priv)
179 {
180 	u8 mac[ETH_ALEN];
181 	unsigned int m;
182 	unsigned int l;
183 	void *addr;
184 
185 	addr = device_get_mac_address(priv->dev, mac, ETH_ALEN);
186 	if (addr) {
187 		ether_addr_copy(priv->netdev->dev_addr, mac);
188 		dev_info(priv->dev, "Read MAC address %pM from device tree\n",
189 			 mac);
190 		return;
191 	}
192 
193 	m = ioread32(priv->base + FTGMAC100_OFFSET_MAC_MADR);
194 	l = ioread32(priv->base + FTGMAC100_OFFSET_MAC_LADR);
195 
196 	mac[0] = (m >> 8) & 0xff;
197 	mac[1] = m & 0xff;
198 	mac[2] = (l >> 24) & 0xff;
199 	mac[3] = (l >> 16) & 0xff;
200 	mac[4] = (l >> 8) & 0xff;
201 	mac[5] = l & 0xff;
202 
203 	if (is_valid_ether_addr(mac)) {
204 		ether_addr_copy(priv->netdev->dev_addr, mac);
205 		dev_info(priv->dev, "Read MAC address %pM from chip\n", mac);
206 	} else {
207 		eth_hw_addr_random(priv->netdev);
208 		dev_info(priv->dev, "Generated random MAC address %pM\n",
209 			 priv->netdev->dev_addr);
210 	}
211 }
212 
213 static int ftgmac100_set_mac_addr(struct net_device *dev, void *p)
214 {
215 	int ret;
216 
217 	ret = eth_prepare_mac_addr_change(dev, p);
218 	if (ret < 0)
219 		return ret;
220 
221 	eth_commit_mac_addr_change(dev, p);
222 	ftgmac100_write_mac_addr(netdev_priv(dev), dev->dev_addr);
223 
224 	return 0;
225 }
226 
227 static void ftgmac100_config_pause(struct ftgmac100 *priv)
228 {
229 	u32 fcr = FTGMAC100_FCR_PAUSE_TIME(16);
230 
231 	/* Throttle tx queue when receiving pause frames */
232 	if (priv->rx_pause)
233 		fcr |= FTGMAC100_FCR_FC_EN;
234 
235 	/* Enables sending pause frames when the RX queue is past a
236 	 * certain threshold.
237 	 */
238 	if (priv->tx_pause)
239 		fcr |= FTGMAC100_FCR_FCTHR_EN;
240 
241 	iowrite32(fcr, priv->base + FTGMAC100_OFFSET_FCR);
242 }
243 
244 static void ftgmac100_init_hw(struct ftgmac100 *priv)
245 {
246 	u32 reg, rfifo_sz, tfifo_sz;
247 
248 	/* Clear stale interrupts */
249 	reg = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
250 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_ISR);
251 
252 	/* Setup RX ring buffer base */
253 	iowrite32(priv->rxdes_dma, priv->base + FTGMAC100_OFFSET_RXR_BADR);
254 
255 	/* Setup TX ring buffer base */
256 	iowrite32(priv->txdes_dma, priv->base + FTGMAC100_OFFSET_NPTXR_BADR);
257 
258 	/* Configure RX buffer size */
259 	iowrite32(FTGMAC100_RBSR_SIZE(RX_BUF_SIZE),
260 		  priv->base + FTGMAC100_OFFSET_RBSR);
261 
262 	/* Set RX descriptor autopoll */
263 	iowrite32(FTGMAC100_APTC_RXPOLL_CNT(1),
264 		  priv->base + FTGMAC100_OFFSET_APTC);
265 
266 	/* Write MAC address */
267 	ftgmac100_write_mac_addr(priv, priv->netdev->dev_addr);
268 
269 	/* Write multicast filter */
270 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
271 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
272 
273 	/* Configure descriptor sizes and increase burst sizes according
274 	 * to values in Aspeed SDK. The FIFO arbitration is enabled and
275 	 * the thresholds set based on the recommended values in the
276 	 * AST2400 specification.
277 	 */
278 	iowrite32(FTGMAC100_DBLAC_RXDES_SIZE(2) |   /* 2*8 bytes RX descs */
279 		  FTGMAC100_DBLAC_TXDES_SIZE(2) |   /* 2*8 bytes TX descs */
280 		  FTGMAC100_DBLAC_RXBURST_SIZE(3) | /* 512 bytes max RX bursts */
281 		  FTGMAC100_DBLAC_TXBURST_SIZE(3) | /* 512 bytes max TX bursts */
282 		  FTGMAC100_DBLAC_RX_THR_EN |       /* Enable fifo threshold arb */
283 		  FTGMAC100_DBLAC_RXFIFO_HTHR(6) |  /* 6/8 of FIFO high threshold */
284 		  FTGMAC100_DBLAC_RXFIFO_LTHR(2),   /* 2/8 of FIFO low threshold */
285 		  priv->base + FTGMAC100_OFFSET_DBLAC);
286 
287 	/* Interrupt mitigation configured for 1 interrupt/packet. HW interrupt
288 	 * mitigation doesn't seem to provide any benefit with NAPI so leave
289 	 * it at that.
290 	 */
291 	iowrite32(FTGMAC100_ITC_RXINT_THR(1) |
292 		  FTGMAC100_ITC_TXINT_THR(1),
293 		  priv->base + FTGMAC100_OFFSET_ITC);
294 
295 	/* Configure FIFO sizes in the TPAFCR register */
296 	reg = ioread32(priv->base + FTGMAC100_OFFSET_FEAR);
297 	rfifo_sz = reg & 0x00000007;
298 	tfifo_sz = (reg >> 3) & 0x00000007;
299 	reg = ioread32(priv->base + FTGMAC100_OFFSET_TPAFCR);
300 	reg &= ~0x3f000000;
301 	reg |= (tfifo_sz << 27);
302 	reg |= (rfifo_sz << 24);
303 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_TPAFCR);
304 }
305 
306 static void ftgmac100_start_hw(struct ftgmac100 *priv)
307 {
308 	u32 maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
309 
310 	/* Keep the original GMAC and FAST bits */
311 	maccr &= (FTGMAC100_MACCR_FAST_MODE | FTGMAC100_MACCR_GIGA_MODE);
312 
313 	/* Add all the main enable bits */
314 	maccr |= FTGMAC100_MACCR_TXDMA_EN	|
315 		 FTGMAC100_MACCR_RXDMA_EN	|
316 		 FTGMAC100_MACCR_TXMAC_EN	|
317 		 FTGMAC100_MACCR_RXMAC_EN	|
318 		 FTGMAC100_MACCR_CRC_APD	|
319 		 FTGMAC100_MACCR_PHY_LINK_LEVEL	|
320 		 FTGMAC100_MACCR_RX_RUNT	|
321 		 FTGMAC100_MACCR_RX_BROADPKT;
322 
323 	/* Add other bits as needed */
324 	if (priv->cur_duplex == DUPLEX_FULL)
325 		maccr |= FTGMAC100_MACCR_FULLDUP;
326 	if (priv->netdev->flags & IFF_PROMISC)
327 		maccr |= FTGMAC100_MACCR_RX_ALL;
328 	if (priv->netdev->flags & IFF_ALLMULTI)
329 		maccr |= FTGMAC100_MACCR_RX_MULTIPKT;
330 	else if (netdev_mc_count(priv->netdev))
331 		maccr |= FTGMAC100_MACCR_HT_MULTI_EN;
332 
333 	/* Vlan filtering enabled */
334 	if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
335 		maccr |= FTGMAC100_MACCR_RM_VLAN;
336 
337 	/* Hit the HW */
338 	iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
339 }
340 
341 static void ftgmac100_stop_hw(struct ftgmac100 *priv)
342 {
343 	iowrite32(0, priv->base + FTGMAC100_OFFSET_MACCR);
344 }
345 
346 static void ftgmac100_calc_mc_hash(struct ftgmac100 *priv)
347 {
348 	struct netdev_hw_addr *ha;
349 
350 	priv->maht1 = 0;
351 	priv->maht0 = 0;
352 	netdev_for_each_mc_addr(ha, priv->netdev) {
353 		u32 crc_val = ether_crc_le(ETH_ALEN, ha->addr);
354 
355 		crc_val = (~(crc_val >> 2)) & 0x3f;
356 		if (crc_val >= 32)
357 			priv->maht1 |= 1ul << (crc_val - 32);
358 		else
359 			priv->maht0 |= 1ul << (crc_val);
360 	}
361 }
362 
363 static void ftgmac100_set_rx_mode(struct net_device *netdev)
364 {
365 	struct ftgmac100 *priv = netdev_priv(netdev);
366 
367 	/* Setup the hash filter */
368 	ftgmac100_calc_mc_hash(priv);
369 
370 	/* Interface down ? that's all there is to do */
371 	if (!netif_running(netdev))
372 		return;
373 
374 	/* Update the HW */
375 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
376 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
377 
378 	/* Reconfigure MACCR */
379 	ftgmac100_start_hw(priv);
380 }
381 
382 static int ftgmac100_alloc_rx_buf(struct ftgmac100 *priv, unsigned int entry,
383 				  struct ftgmac100_rxdes *rxdes, gfp_t gfp)
384 {
385 	struct net_device *netdev = priv->netdev;
386 	struct sk_buff *skb;
387 	dma_addr_t map;
388 	int err = 0;
389 
390 	skb = netdev_alloc_skb_ip_align(netdev, RX_BUF_SIZE);
391 	if (unlikely(!skb)) {
392 		if (net_ratelimit())
393 			netdev_warn(netdev, "failed to allocate rx skb\n");
394 		err = -ENOMEM;
395 		map = priv->rx_scratch_dma;
396 	} else {
397 		map = dma_map_single(priv->dev, skb->data, RX_BUF_SIZE,
398 				     DMA_FROM_DEVICE);
399 		if (unlikely(dma_mapping_error(priv->dev, map))) {
400 			if (net_ratelimit())
401 				netdev_err(netdev, "failed to map rx page\n");
402 			dev_kfree_skb_any(skb);
403 			map = priv->rx_scratch_dma;
404 			skb = NULL;
405 			err = -ENOMEM;
406 		}
407 	}
408 
409 	/* Store skb */
410 	priv->rx_skbs[entry] = skb;
411 
412 	/* Store DMA address into RX desc */
413 	rxdes->rxdes3 = cpu_to_le32(map);
414 
415 	/* Ensure the above is ordered vs clearing the OWN bit */
416 	dma_wmb();
417 
418 	/* Clean status (which resets own bit) */
419 	if (entry == (priv->rx_q_entries - 1))
420 		rxdes->rxdes0 = cpu_to_le32(priv->rxdes0_edorr_mask);
421 	else
422 		rxdes->rxdes0 = 0;
423 
424 	return err;
425 }
426 
427 static unsigned int ftgmac100_next_rx_pointer(struct ftgmac100 *priv,
428 					      unsigned int pointer)
429 {
430 	return (pointer + 1) & (priv->rx_q_entries - 1);
431 }
432 
433 static void ftgmac100_rx_packet_error(struct ftgmac100 *priv, u32 status)
434 {
435 	struct net_device *netdev = priv->netdev;
436 
437 	if (status & FTGMAC100_RXDES0_RX_ERR)
438 		netdev->stats.rx_errors++;
439 
440 	if (status & FTGMAC100_RXDES0_CRC_ERR)
441 		netdev->stats.rx_crc_errors++;
442 
443 	if (status & (FTGMAC100_RXDES0_FTL |
444 		      FTGMAC100_RXDES0_RUNT |
445 		      FTGMAC100_RXDES0_RX_ODD_NB))
446 		netdev->stats.rx_length_errors++;
447 }
448 
449 static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed)
450 {
451 	struct net_device *netdev = priv->netdev;
452 	struct ftgmac100_rxdes *rxdes;
453 	struct sk_buff *skb;
454 	unsigned int pointer, size;
455 	u32 status, csum_vlan;
456 	dma_addr_t map;
457 
458 	/* Grab next RX descriptor */
459 	pointer = priv->rx_pointer;
460 	rxdes = &priv->rxdes[pointer];
461 
462 	/* Grab descriptor status */
463 	status = le32_to_cpu(rxdes->rxdes0);
464 
465 	/* Do we have a packet ? */
466 	if (!(status & FTGMAC100_RXDES0_RXPKT_RDY))
467 		return false;
468 
469 	/* Order subsequent reads with the test for the ready bit */
470 	dma_rmb();
471 
472 	/* We don't cope with fragmented RX packets */
473 	if (unlikely(!(status & FTGMAC100_RXDES0_FRS) ||
474 		     !(status & FTGMAC100_RXDES0_LRS)))
475 		goto drop;
476 
477 	/* Grab received size and csum vlan field in the descriptor */
478 	size = status & FTGMAC100_RXDES0_VDBC;
479 	csum_vlan = le32_to_cpu(rxdes->rxdes1);
480 
481 	/* Any error (other than csum offload) flagged ? */
482 	if (unlikely(status & RXDES0_ANY_ERROR)) {
483 		/* Correct for incorrect flagging of runt packets
484 		 * with vlan tags... Just accept a runt packet that
485 		 * has been flagged as vlan and whose size is at
486 		 * least 60 bytes.
487 		 */
488 		if ((status & FTGMAC100_RXDES0_RUNT) &&
489 		    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL) &&
490 		    (size >= 60))
491 			status &= ~FTGMAC100_RXDES0_RUNT;
492 
493 		/* Any error still in there ? */
494 		if (status & RXDES0_ANY_ERROR) {
495 			ftgmac100_rx_packet_error(priv, status);
496 			goto drop;
497 		}
498 	}
499 
500 	/* If the packet had no skb (failed to allocate earlier)
501 	 * then try to allocate one and skip
502 	 */
503 	skb = priv->rx_skbs[pointer];
504 	if (!unlikely(skb)) {
505 		ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
506 		goto drop;
507 	}
508 
509 	if (unlikely(status & FTGMAC100_RXDES0_MULTICAST))
510 		netdev->stats.multicast++;
511 
512 	/* If the HW found checksum errors, bounce it to software.
513 	 *
514 	 * If we didn't, we need to see if the packet was recognized
515 	 * by HW as one of the supported checksummed protocols before
516 	 * we accept the HW test results.
517 	 */
518 	if (netdev->features & NETIF_F_RXCSUM) {
519 		u32 err_bits = FTGMAC100_RXDES1_TCP_CHKSUM_ERR |
520 			FTGMAC100_RXDES1_UDP_CHKSUM_ERR |
521 			FTGMAC100_RXDES1_IP_CHKSUM_ERR;
522 		if ((csum_vlan & err_bits) ||
523 		    !(csum_vlan & FTGMAC100_RXDES1_PROT_MASK))
524 			skb->ip_summed = CHECKSUM_NONE;
525 		else
526 			skb->ip_summed = CHECKSUM_UNNECESSARY;
527 	}
528 
529 	/* Transfer received size to skb */
530 	skb_put(skb, size);
531 
532 	/* Extract vlan tag */
533 	if ((netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
534 	    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL))
535 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
536 				       csum_vlan & 0xffff);
537 
538 	/* Tear down DMA mapping, do necessary cache management */
539 	map = le32_to_cpu(rxdes->rxdes3);
540 
541 #if defined(CONFIG_ARM) && !defined(CONFIG_ARM_DMA_USE_IOMMU)
542 	/* When we don't have an iommu, we can save cycles by not
543 	 * invalidating the cache for the part of the packet that
544 	 * wasn't received.
545 	 */
546 	dma_unmap_single(priv->dev, map, size, DMA_FROM_DEVICE);
547 #else
548 	dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
549 #endif
550 
551 
552 	/* Resplenish rx ring */
553 	ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
554 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
555 
556 	skb->protocol = eth_type_trans(skb, netdev);
557 
558 	netdev->stats.rx_packets++;
559 	netdev->stats.rx_bytes += size;
560 
561 	/* push packet to protocol stack */
562 	if (skb->ip_summed == CHECKSUM_NONE)
563 		netif_receive_skb(skb);
564 	else
565 		napi_gro_receive(&priv->napi, skb);
566 
567 	(*processed)++;
568 	return true;
569 
570  drop:
571 	/* Clean rxdes0 (which resets own bit) */
572 	rxdes->rxdes0 = cpu_to_le32(status & priv->rxdes0_edorr_mask);
573 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
574 	netdev->stats.rx_dropped++;
575 	return true;
576 }
577 
578 static u32 ftgmac100_base_tx_ctlstat(struct ftgmac100 *priv,
579 				     unsigned int index)
580 {
581 	if (index == (priv->tx_q_entries - 1))
582 		return priv->txdes0_edotr_mask;
583 	else
584 		return 0;
585 }
586 
587 static unsigned int ftgmac100_next_tx_pointer(struct ftgmac100 *priv,
588 					      unsigned int pointer)
589 {
590 	return (pointer + 1) & (priv->tx_q_entries - 1);
591 }
592 
593 static u32 ftgmac100_tx_buf_avail(struct ftgmac100 *priv)
594 {
595 	/* Returns the number of available slots in the TX queue
596 	 *
597 	 * This always leaves one free slot so we don't have to
598 	 * worry about empty vs. full, and this simplifies the
599 	 * test for ftgmac100_tx_buf_cleanable() below
600 	 */
601 	return (priv->tx_clean_pointer - priv->tx_pointer - 1) &
602 		(priv->tx_q_entries - 1);
603 }
604 
605 static bool ftgmac100_tx_buf_cleanable(struct ftgmac100 *priv)
606 {
607 	return priv->tx_pointer != priv->tx_clean_pointer;
608 }
609 
610 static void ftgmac100_free_tx_packet(struct ftgmac100 *priv,
611 				     unsigned int pointer,
612 				     struct sk_buff *skb,
613 				     struct ftgmac100_txdes *txdes,
614 				     u32 ctl_stat)
615 {
616 	dma_addr_t map = le32_to_cpu(txdes->txdes3);
617 	size_t len;
618 
619 	if (ctl_stat & FTGMAC100_TXDES0_FTS) {
620 		len = skb_headlen(skb);
621 		dma_unmap_single(priv->dev, map, len, DMA_TO_DEVICE);
622 	} else {
623 		len = FTGMAC100_TXDES0_TXBUF_SIZE(ctl_stat);
624 		dma_unmap_page(priv->dev, map, len, DMA_TO_DEVICE);
625 	}
626 
627 	/* Free SKB on last segment */
628 	if (ctl_stat & FTGMAC100_TXDES0_LTS)
629 		dev_kfree_skb(skb);
630 	priv->tx_skbs[pointer] = NULL;
631 }
632 
633 static bool ftgmac100_tx_complete_packet(struct ftgmac100 *priv)
634 {
635 	struct net_device *netdev = priv->netdev;
636 	struct ftgmac100_txdes *txdes;
637 	struct sk_buff *skb;
638 	unsigned int pointer;
639 	u32 ctl_stat;
640 
641 	pointer = priv->tx_clean_pointer;
642 	txdes = &priv->txdes[pointer];
643 
644 	ctl_stat = le32_to_cpu(txdes->txdes0);
645 	if (ctl_stat & FTGMAC100_TXDES0_TXDMA_OWN)
646 		return false;
647 
648 	skb = priv->tx_skbs[pointer];
649 	netdev->stats.tx_packets++;
650 	netdev->stats.tx_bytes += skb->len;
651 	ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
652 	txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
653 
654 	priv->tx_clean_pointer = ftgmac100_next_tx_pointer(priv, pointer);
655 
656 	return true;
657 }
658 
659 static void ftgmac100_tx_complete(struct ftgmac100 *priv)
660 {
661 	struct net_device *netdev = priv->netdev;
662 
663 	/* Process all completed packets */
664 	while (ftgmac100_tx_buf_cleanable(priv) &&
665 	       ftgmac100_tx_complete_packet(priv))
666 		;
667 
668 	/* Restart queue if needed */
669 	smp_mb();
670 	if (unlikely(netif_queue_stopped(netdev) &&
671 		     ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)) {
672 		struct netdev_queue *txq;
673 
674 		txq = netdev_get_tx_queue(netdev, 0);
675 		__netif_tx_lock(txq, smp_processor_id());
676 		if (netif_queue_stopped(netdev) &&
677 		    ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
678 			netif_wake_queue(netdev);
679 		__netif_tx_unlock(txq);
680 	}
681 }
682 
683 static bool ftgmac100_prep_tx_csum(struct sk_buff *skb, u32 *csum_vlan)
684 {
685 	if (skb->protocol == cpu_to_be16(ETH_P_IP)) {
686 		u8 ip_proto = ip_hdr(skb)->protocol;
687 
688 		*csum_vlan |= FTGMAC100_TXDES1_IP_CHKSUM;
689 		switch(ip_proto) {
690 		case IPPROTO_TCP:
691 			*csum_vlan |= FTGMAC100_TXDES1_TCP_CHKSUM;
692 			return true;
693 		case IPPROTO_UDP:
694 			*csum_vlan |= FTGMAC100_TXDES1_UDP_CHKSUM;
695 			return true;
696 		case IPPROTO_IP:
697 			return true;
698 		}
699 	}
700 	return skb_checksum_help(skb) == 0;
701 }
702 
703 static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb,
704 					     struct net_device *netdev)
705 {
706 	struct ftgmac100 *priv = netdev_priv(netdev);
707 	struct ftgmac100_txdes *txdes, *first;
708 	unsigned int pointer, nfrags, len, i, j;
709 	u32 f_ctl_stat, ctl_stat, csum_vlan;
710 	dma_addr_t map;
711 
712 	/* The HW doesn't pad small frames */
713 	if (eth_skb_pad(skb)) {
714 		netdev->stats.tx_dropped++;
715 		return NETDEV_TX_OK;
716 	}
717 
718 	/* Reject oversize packets */
719 	if (unlikely(skb->len > MAX_PKT_SIZE)) {
720 		if (net_ratelimit())
721 			netdev_dbg(netdev, "tx packet too big\n");
722 		goto drop;
723 	}
724 
725 	/* Do we have a limit on #fragments ? I yet have to get a reply
726 	 * from Aspeed. If there's one I haven't hit it.
727 	 */
728 	nfrags = skb_shinfo(skb)->nr_frags;
729 
730 	/* Get header len */
731 	len = skb_headlen(skb);
732 
733 	/* Map the packet head */
734 	map = dma_map_single(priv->dev, skb->data, len, DMA_TO_DEVICE);
735 	if (dma_mapping_error(priv->dev, map)) {
736 		if (net_ratelimit())
737 			netdev_err(netdev, "map tx packet head failed\n");
738 		goto drop;
739 	}
740 
741 	/* Grab the next free tx descriptor */
742 	pointer = priv->tx_pointer;
743 	txdes = first = &priv->txdes[pointer];
744 
745 	/* Setup it up with the packet head. Don't write the head to the
746 	 * ring just yet
747 	 */
748 	priv->tx_skbs[pointer] = skb;
749 	f_ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
750 	f_ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
751 	f_ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
752 	f_ctl_stat |= FTGMAC100_TXDES0_FTS;
753 	if (nfrags == 0)
754 		f_ctl_stat |= FTGMAC100_TXDES0_LTS;
755 	txdes->txdes3 = cpu_to_le32(map);
756 
757 	/* Setup HW checksumming */
758 	csum_vlan = 0;
759 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
760 	    !ftgmac100_prep_tx_csum(skb, &csum_vlan))
761 		goto drop;
762 
763 	/* Add VLAN tag */
764 	if (skb_vlan_tag_present(skb)) {
765 		csum_vlan |= FTGMAC100_TXDES1_INS_VLANTAG;
766 		csum_vlan |= skb_vlan_tag_get(skb) & 0xffff;
767 	}
768 
769 	txdes->txdes1 = cpu_to_le32(csum_vlan);
770 
771 	/* Next descriptor */
772 	pointer = ftgmac100_next_tx_pointer(priv, pointer);
773 
774 	/* Add the fragments */
775 	for (i = 0; i < nfrags; i++) {
776 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
777 
778 		len = skb_frag_size(frag);
779 
780 		/* Map it */
781 		map = skb_frag_dma_map(priv->dev, frag, 0, len,
782 				       DMA_TO_DEVICE);
783 		if (dma_mapping_error(priv->dev, map))
784 			goto dma_err;
785 
786 		/* Setup descriptor */
787 		priv->tx_skbs[pointer] = skb;
788 		txdes = &priv->txdes[pointer];
789 		ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
790 		ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
791 		ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
792 		if (i == (nfrags - 1))
793 			ctl_stat |= FTGMAC100_TXDES0_LTS;
794 		txdes->txdes0 = cpu_to_le32(ctl_stat);
795 		txdes->txdes1 = 0;
796 		txdes->txdes3 = cpu_to_le32(map);
797 
798 		/* Next one */
799 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
800 	}
801 
802 	/* Order the previous packet and descriptor udpates
803 	 * before setting the OWN bit on the first descriptor.
804 	 */
805 	dma_wmb();
806 	first->txdes0 = cpu_to_le32(f_ctl_stat);
807 
808 	/* Update next TX pointer */
809 	priv->tx_pointer = pointer;
810 
811 	/* If there isn't enough room for all the fragments of a new packet
812 	 * in the TX ring, stop the queue. The sequence below is race free
813 	 * vs. a concurrent restart in ftgmac100_poll()
814 	 */
815 	if (unlikely(ftgmac100_tx_buf_avail(priv) < TX_THRESHOLD)) {
816 		netif_stop_queue(netdev);
817 		/* Order the queue stop with the test below */
818 		smp_mb();
819 		if (ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
820 			netif_wake_queue(netdev);
821 	}
822 
823 	/* Poke transmitter to read the updated TX descriptors */
824 	iowrite32(1, priv->base + FTGMAC100_OFFSET_NPTXPD);
825 
826 	return NETDEV_TX_OK;
827 
828  dma_err:
829 	if (net_ratelimit())
830 		netdev_err(netdev, "map tx fragment failed\n");
831 
832 	/* Free head */
833 	pointer = priv->tx_pointer;
834 	ftgmac100_free_tx_packet(priv, pointer, skb, first, f_ctl_stat);
835 	first->txdes0 = cpu_to_le32(f_ctl_stat & priv->txdes0_edotr_mask);
836 
837 	/* Then all fragments */
838 	for (j = 0; j < i; j++) {
839 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
840 		txdes = &priv->txdes[pointer];
841 		ctl_stat = le32_to_cpu(txdes->txdes0);
842 		ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
843 		txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
844 	}
845 
846 	/* This cannot be reached if we successfully mapped the
847 	 * last fragment, so we know ftgmac100_free_tx_packet()
848 	 * hasn't freed the skb yet.
849 	 */
850  drop:
851 	/* Drop the packet */
852 	dev_kfree_skb_any(skb);
853 	netdev->stats.tx_dropped++;
854 
855 	return NETDEV_TX_OK;
856 }
857 
858 static void ftgmac100_free_buffers(struct ftgmac100 *priv)
859 {
860 	int i;
861 
862 	/* Free all RX buffers */
863 	for (i = 0; i < priv->rx_q_entries; i++) {
864 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
865 		struct sk_buff *skb = priv->rx_skbs[i];
866 		dma_addr_t map = le32_to_cpu(rxdes->rxdes3);
867 
868 		if (!skb)
869 			continue;
870 
871 		priv->rx_skbs[i] = NULL;
872 		dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
873 		dev_kfree_skb_any(skb);
874 	}
875 
876 	/* Free all TX buffers */
877 	for (i = 0; i < priv->tx_q_entries; i++) {
878 		struct ftgmac100_txdes *txdes = &priv->txdes[i];
879 		struct sk_buff *skb = priv->tx_skbs[i];
880 
881 		if (!skb)
882 			continue;
883 		ftgmac100_free_tx_packet(priv, i, skb, txdes,
884 					 le32_to_cpu(txdes->txdes0));
885 	}
886 }
887 
888 static void ftgmac100_free_rings(struct ftgmac100 *priv)
889 {
890 	/* Free skb arrays */
891 	kfree(priv->rx_skbs);
892 	kfree(priv->tx_skbs);
893 
894 	/* Free descriptors */
895 	if (priv->rxdes)
896 		dma_free_coherent(priv->dev, MAX_RX_QUEUE_ENTRIES *
897 				  sizeof(struct ftgmac100_rxdes),
898 				  priv->rxdes, priv->rxdes_dma);
899 	priv->rxdes = NULL;
900 
901 	if (priv->txdes)
902 		dma_free_coherent(priv->dev, MAX_TX_QUEUE_ENTRIES *
903 				  sizeof(struct ftgmac100_txdes),
904 				  priv->txdes, priv->txdes_dma);
905 	priv->txdes = NULL;
906 
907 	/* Free scratch packet buffer */
908 	if (priv->rx_scratch)
909 		dma_free_coherent(priv->dev, RX_BUF_SIZE,
910 				  priv->rx_scratch, priv->rx_scratch_dma);
911 }
912 
913 static int ftgmac100_alloc_rings(struct ftgmac100 *priv)
914 {
915 	/* Allocate skb arrays */
916 	priv->rx_skbs = kcalloc(MAX_RX_QUEUE_ENTRIES, sizeof(void *),
917 				GFP_KERNEL);
918 	if (!priv->rx_skbs)
919 		return -ENOMEM;
920 	priv->tx_skbs = kcalloc(MAX_TX_QUEUE_ENTRIES, sizeof(void *),
921 				GFP_KERNEL);
922 	if (!priv->tx_skbs)
923 		return -ENOMEM;
924 
925 	/* Allocate descriptors */
926 	priv->rxdes = dma_alloc_coherent(priv->dev,
927 					 MAX_RX_QUEUE_ENTRIES * sizeof(struct ftgmac100_rxdes),
928 					 &priv->rxdes_dma, GFP_KERNEL);
929 	if (!priv->rxdes)
930 		return -ENOMEM;
931 	priv->txdes = dma_alloc_coherent(priv->dev,
932 					 MAX_TX_QUEUE_ENTRIES * sizeof(struct ftgmac100_txdes),
933 					 &priv->txdes_dma, GFP_KERNEL);
934 	if (!priv->txdes)
935 		return -ENOMEM;
936 
937 	/* Allocate scratch packet buffer */
938 	priv->rx_scratch = dma_alloc_coherent(priv->dev,
939 					      RX_BUF_SIZE,
940 					      &priv->rx_scratch_dma,
941 					      GFP_KERNEL);
942 	if (!priv->rx_scratch)
943 		return -ENOMEM;
944 
945 	return 0;
946 }
947 
948 static void ftgmac100_init_rings(struct ftgmac100 *priv)
949 {
950 	struct ftgmac100_rxdes *rxdes = NULL;
951 	struct ftgmac100_txdes *txdes = NULL;
952 	int i;
953 
954 	/* Update entries counts */
955 	priv->rx_q_entries = priv->new_rx_q_entries;
956 	priv->tx_q_entries = priv->new_tx_q_entries;
957 
958 	if (WARN_ON(priv->rx_q_entries < MIN_RX_QUEUE_ENTRIES))
959 		return;
960 
961 	/* Initialize RX ring */
962 	for (i = 0; i < priv->rx_q_entries; i++) {
963 		rxdes = &priv->rxdes[i];
964 		rxdes->rxdes0 = 0;
965 		rxdes->rxdes3 = cpu_to_le32(priv->rx_scratch_dma);
966 	}
967 	/* Mark the end of the ring */
968 	rxdes->rxdes0 |= cpu_to_le32(priv->rxdes0_edorr_mask);
969 
970 	if (WARN_ON(priv->tx_q_entries < MIN_RX_QUEUE_ENTRIES))
971 		return;
972 
973 	/* Initialize TX ring */
974 	for (i = 0; i < priv->tx_q_entries; i++) {
975 		txdes = &priv->txdes[i];
976 		txdes->txdes0 = 0;
977 	}
978 	txdes->txdes0 |= cpu_to_le32(priv->txdes0_edotr_mask);
979 }
980 
981 static int ftgmac100_alloc_rx_buffers(struct ftgmac100 *priv)
982 {
983 	int i;
984 
985 	for (i = 0; i < priv->rx_q_entries; i++) {
986 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
987 
988 		if (ftgmac100_alloc_rx_buf(priv, i, rxdes, GFP_KERNEL))
989 			return -ENOMEM;
990 	}
991 	return 0;
992 }
993 
994 static void ftgmac100_adjust_link(struct net_device *netdev)
995 {
996 	struct ftgmac100 *priv = netdev_priv(netdev);
997 	struct phy_device *phydev = netdev->phydev;
998 	bool tx_pause, rx_pause;
999 	int new_speed;
1000 
1001 	/* We store "no link" as speed 0 */
1002 	if (!phydev->link)
1003 		new_speed = 0;
1004 	else
1005 		new_speed = phydev->speed;
1006 
1007 	/* Grab pause settings from PHY if configured to do so */
1008 	if (priv->aneg_pause) {
1009 		rx_pause = tx_pause = phydev->pause;
1010 		if (phydev->asym_pause)
1011 			tx_pause = !rx_pause;
1012 	} else {
1013 		rx_pause = priv->rx_pause;
1014 		tx_pause = priv->tx_pause;
1015 	}
1016 
1017 	/* Link hasn't changed, do nothing */
1018 	if (phydev->speed == priv->cur_speed &&
1019 	    phydev->duplex == priv->cur_duplex &&
1020 	    rx_pause == priv->rx_pause &&
1021 	    tx_pause == priv->tx_pause)
1022 		return;
1023 
1024 	/* Print status if we have a link or we had one and just lost it,
1025 	 * don't print otherwise.
1026 	 */
1027 	if (new_speed || priv->cur_speed)
1028 		phy_print_status(phydev);
1029 
1030 	priv->cur_speed = new_speed;
1031 	priv->cur_duplex = phydev->duplex;
1032 	priv->rx_pause = rx_pause;
1033 	priv->tx_pause = tx_pause;
1034 
1035 	/* Link is down, do nothing else */
1036 	if (!new_speed)
1037 		return;
1038 
1039 	/* Disable all interrupts */
1040 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1041 
1042 	/* Reset the adapter asynchronously */
1043 	schedule_work(&priv->reset_task);
1044 }
1045 
1046 static int ftgmac100_mii_probe(struct ftgmac100 *priv, phy_interface_t intf)
1047 {
1048 	struct net_device *netdev = priv->netdev;
1049 	struct phy_device *phydev;
1050 
1051 	phydev = phy_find_first(priv->mii_bus);
1052 	if (!phydev) {
1053 		netdev_info(netdev, "%s: no PHY found\n", netdev->name);
1054 		return -ENODEV;
1055 	}
1056 
1057 	phydev = phy_connect(netdev, phydev_name(phydev),
1058 			     &ftgmac100_adjust_link, intf);
1059 
1060 	if (IS_ERR(phydev)) {
1061 		netdev_err(netdev, "%s: Could not attach to PHY\n", netdev->name);
1062 		return PTR_ERR(phydev);
1063 	}
1064 
1065 	/* Indicate that we support PAUSE frames (see comment in
1066 	 * Documentation/networking/phy.rst)
1067 	 */
1068 	phy_support_asym_pause(phydev);
1069 
1070 	/* Display what we found */
1071 	phy_attached_info(phydev);
1072 
1073 	return 0;
1074 }
1075 
1076 static int ftgmac100_mdiobus_read(struct mii_bus *bus, int phy_addr, int regnum)
1077 {
1078 	struct net_device *netdev = bus->priv;
1079 	struct ftgmac100 *priv = netdev_priv(netdev);
1080 	unsigned int phycr;
1081 	int i;
1082 
1083 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1084 
1085 	/* preserve MDC cycle threshold */
1086 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1087 
1088 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1089 		 FTGMAC100_PHYCR_REGAD(regnum) |
1090 		 FTGMAC100_PHYCR_MIIRD;
1091 
1092 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1093 
1094 	for (i = 0; i < 10; i++) {
1095 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1096 
1097 		if ((phycr & FTGMAC100_PHYCR_MIIRD) == 0) {
1098 			int data;
1099 
1100 			data = ioread32(priv->base + FTGMAC100_OFFSET_PHYDATA);
1101 			return FTGMAC100_PHYDATA_MIIRDATA(data);
1102 		}
1103 
1104 		udelay(100);
1105 	}
1106 
1107 	netdev_err(netdev, "mdio read timed out\n");
1108 	return -EIO;
1109 }
1110 
1111 static int ftgmac100_mdiobus_write(struct mii_bus *bus, int phy_addr,
1112 				   int regnum, u16 value)
1113 {
1114 	struct net_device *netdev = bus->priv;
1115 	struct ftgmac100 *priv = netdev_priv(netdev);
1116 	unsigned int phycr;
1117 	int data;
1118 	int i;
1119 
1120 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1121 
1122 	/* preserve MDC cycle threshold */
1123 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1124 
1125 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1126 		 FTGMAC100_PHYCR_REGAD(regnum) |
1127 		 FTGMAC100_PHYCR_MIIWR;
1128 
1129 	data = FTGMAC100_PHYDATA_MIIWDATA(value);
1130 
1131 	iowrite32(data, priv->base + FTGMAC100_OFFSET_PHYDATA);
1132 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1133 
1134 	for (i = 0; i < 10; i++) {
1135 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1136 
1137 		if ((phycr & FTGMAC100_PHYCR_MIIWR) == 0)
1138 			return 0;
1139 
1140 		udelay(100);
1141 	}
1142 
1143 	netdev_err(netdev, "mdio write timed out\n");
1144 	return -EIO;
1145 }
1146 
1147 static void ftgmac100_get_drvinfo(struct net_device *netdev,
1148 				  struct ethtool_drvinfo *info)
1149 {
1150 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1151 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
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 /* optional */
1538 static int ftgmac100_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1539 {
1540 	if (!netdev->phydev)
1541 		return -ENXIO;
1542 
1543 	return phy_mii_ioctl(netdev->phydev, ifr, cmd);
1544 }
1545 
1546 static void ftgmac100_tx_timeout(struct net_device *netdev)
1547 {
1548 	struct ftgmac100 *priv = netdev_priv(netdev);
1549 
1550 	/* Disable all interrupts */
1551 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1552 
1553 	/* Do the reset outside of interrupt context */
1554 	schedule_work(&priv->reset_task);
1555 }
1556 
1557 static int ftgmac100_set_features(struct net_device *netdev,
1558 				  netdev_features_t features)
1559 {
1560 	struct ftgmac100 *priv = netdev_priv(netdev);
1561 	netdev_features_t changed = netdev->features ^ features;
1562 
1563 	if (!netif_running(netdev))
1564 		return 0;
1565 
1566 	/* Update the vlan filtering bit */
1567 	if (changed & NETIF_F_HW_VLAN_CTAG_RX) {
1568 		u32 maccr;
1569 
1570 		maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
1571 		if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
1572 			maccr |= FTGMAC100_MACCR_RM_VLAN;
1573 		else
1574 			maccr &= ~FTGMAC100_MACCR_RM_VLAN;
1575 		iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
1576 	}
1577 
1578 	return 0;
1579 }
1580 
1581 #ifdef CONFIG_NET_POLL_CONTROLLER
1582 static void ftgmac100_poll_controller(struct net_device *netdev)
1583 {
1584 	unsigned long flags;
1585 
1586 	local_irq_save(flags);
1587 	ftgmac100_interrupt(netdev->irq, netdev);
1588 	local_irq_restore(flags);
1589 }
1590 #endif
1591 
1592 static const struct net_device_ops ftgmac100_netdev_ops = {
1593 	.ndo_open		= ftgmac100_open,
1594 	.ndo_stop		= ftgmac100_stop,
1595 	.ndo_start_xmit		= ftgmac100_hard_start_xmit,
1596 	.ndo_set_mac_address	= ftgmac100_set_mac_addr,
1597 	.ndo_validate_addr	= eth_validate_addr,
1598 	.ndo_do_ioctl		= ftgmac100_do_ioctl,
1599 	.ndo_tx_timeout		= ftgmac100_tx_timeout,
1600 	.ndo_set_rx_mode	= ftgmac100_set_rx_mode,
1601 	.ndo_set_features	= ftgmac100_set_features,
1602 #ifdef CONFIG_NET_POLL_CONTROLLER
1603 	.ndo_poll_controller	= ftgmac100_poll_controller,
1604 #endif
1605 	.ndo_vlan_rx_add_vid	= ncsi_vlan_rx_add_vid,
1606 	.ndo_vlan_rx_kill_vid	= ncsi_vlan_rx_kill_vid,
1607 };
1608 
1609 static int ftgmac100_setup_mdio(struct net_device *netdev)
1610 {
1611 	struct ftgmac100 *priv = netdev_priv(netdev);
1612 	struct platform_device *pdev = to_platform_device(priv->dev);
1613 	int phy_intf = PHY_INTERFACE_MODE_RGMII;
1614 	struct device_node *np = pdev->dev.of_node;
1615 	int i, err = 0;
1616 	u32 reg;
1617 
1618 	/* initialize mdio bus */
1619 	priv->mii_bus = mdiobus_alloc();
1620 	if (!priv->mii_bus)
1621 		return -EIO;
1622 
1623 	if (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
1624 	    of_device_is_compatible(np, "aspeed,ast2500-mac")) {
1625 		/* The AST2600 has a separate MDIO controller */
1626 
1627 		/* For the AST2400 and AST2500 this driver only supports the
1628 		 * old MDIO interface
1629 		 */
1630 		reg = ioread32(priv->base + FTGMAC100_OFFSET_REVR);
1631 		reg &= ~FTGMAC100_REVR_NEW_MDIO_INTERFACE;
1632 		iowrite32(reg, priv->base + FTGMAC100_OFFSET_REVR);
1633 	}
1634 
1635 	/* Get PHY mode from device-tree */
1636 	if (np) {
1637 		/* Default to RGMII. It's a gigabit part after all */
1638 		phy_intf = of_get_phy_mode(np);
1639 		if (phy_intf < 0)
1640 			phy_intf = PHY_INTERFACE_MODE_RGMII;
1641 
1642 		/* Aspeed only supports these. I don't know about other IP
1643 		 * block vendors so I'm going to just let them through for
1644 		 * now. Note that this is only a warning if for some obscure
1645 		 * reason the DT really means to lie about it or it's a newer
1646 		 * part we don't know about.
1647 		 *
1648 		 * On the Aspeed SoC there are additionally straps and SCU
1649 		 * control bits that could tell us what the interface is
1650 		 * (or allow us to configure it while the IP block is held
1651 		 * in reset). For now I chose to keep this driver away from
1652 		 * those SoC specific bits and assume the device-tree is
1653 		 * right and the SCU has been configured properly by pinmux
1654 		 * or the firmware.
1655 		 */
1656 		if (priv->is_aspeed &&
1657 		    phy_intf != PHY_INTERFACE_MODE_RMII &&
1658 		    phy_intf != PHY_INTERFACE_MODE_RGMII &&
1659 		    phy_intf != PHY_INTERFACE_MODE_RGMII_ID &&
1660 		    phy_intf != PHY_INTERFACE_MODE_RGMII_RXID &&
1661 		    phy_intf != PHY_INTERFACE_MODE_RGMII_TXID) {
1662 			netdev_warn(netdev,
1663 				   "Unsupported PHY mode %s !\n",
1664 				   phy_modes(phy_intf));
1665 		}
1666 	}
1667 
1668 	priv->mii_bus->name = "ftgmac100_mdio";
1669 	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%d",
1670 		 pdev->name, pdev->id);
1671 	priv->mii_bus->parent = priv->dev;
1672 	priv->mii_bus->priv = priv->netdev;
1673 	priv->mii_bus->read = ftgmac100_mdiobus_read;
1674 	priv->mii_bus->write = ftgmac100_mdiobus_write;
1675 
1676 	for (i = 0; i < PHY_MAX_ADDR; i++)
1677 		priv->mii_bus->irq[i] = PHY_POLL;
1678 
1679 	err = mdiobus_register(priv->mii_bus);
1680 	if (err) {
1681 		dev_err(priv->dev, "Cannot register MDIO bus!\n");
1682 		goto err_register_mdiobus;
1683 	}
1684 
1685 	err = ftgmac100_mii_probe(priv, phy_intf);
1686 	if (err) {
1687 		dev_err(priv->dev, "MII Probe failed!\n");
1688 		goto err_mii_probe;
1689 	}
1690 
1691 	return 0;
1692 
1693 err_mii_probe:
1694 	mdiobus_unregister(priv->mii_bus);
1695 err_register_mdiobus:
1696 	mdiobus_free(priv->mii_bus);
1697 	return err;
1698 }
1699 
1700 static void ftgmac100_destroy_mdio(struct net_device *netdev)
1701 {
1702 	struct ftgmac100 *priv = netdev_priv(netdev);
1703 
1704 	if (!netdev->phydev)
1705 		return;
1706 
1707 	phy_disconnect(netdev->phydev);
1708 	mdiobus_unregister(priv->mii_bus);
1709 	mdiobus_free(priv->mii_bus);
1710 }
1711 
1712 static void ftgmac100_ncsi_handler(struct ncsi_dev *nd)
1713 {
1714 	if (unlikely(nd->state != ncsi_dev_state_functional))
1715 		return;
1716 
1717 	netdev_dbg(nd->dev, "NCSI interface %s\n",
1718 		   nd->link_up ? "up" : "down");
1719 }
1720 
1721 static void ftgmac100_setup_clk(struct ftgmac100 *priv)
1722 {
1723 	priv->clk = devm_clk_get(priv->dev, NULL);
1724 	if (IS_ERR(priv->clk))
1725 		return;
1726 
1727 	clk_prepare_enable(priv->clk);
1728 
1729 	/* Aspeed specifies a 100MHz clock is required for up to
1730 	 * 1000Mbit link speeds. As NCSI is limited to 100Mbit, 25MHz
1731 	 * is sufficient
1732 	 */
1733 	clk_set_rate(priv->clk, priv->use_ncsi ? FTGMAC_25MHZ :
1734 			FTGMAC_100MHZ);
1735 }
1736 
1737 static int ftgmac100_probe(struct platform_device *pdev)
1738 {
1739 	struct resource *res;
1740 	int irq;
1741 	struct net_device *netdev;
1742 	struct ftgmac100 *priv;
1743 	struct device_node *np;
1744 	int err = 0;
1745 
1746 	if (!pdev)
1747 		return -ENODEV;
1748 
1749 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1750 	if (!res)
1751 		return -ENXIO;
1752 
1753 	irq = platform_get_irq(pdev, 0);
1754 	if (irq < 0)
1755 		return irq;
1756 
1757 	/* setup net_device */
1758 	netdev = alloc_etherdev(sizeof(*priv));
1759 	if (!netdev) {
1760 		err = -ENOMEM;
1761 		goto err_alloc_etherdev;
1762 	}
1763 
1764 	SET_NETDEV_DEV(netdev, &pdev->dev);
1765 
1766 	netdev->ethtool_ops = &ftgmac100_ethtool_ops;
1767 	netdev->netdev_ops = &ftgmac100_netdev_ops;
1768 	netdev->watchdog_timeo = 5 * HZ;
1769 
1770 	platform_set_drvdata(pdev, netdev);
1771 
1772 	/* setup private data */
1773 	priv = netdev_priv(netdev);
1774 	priv->netdev = netdev;
1775 	priv->dev = &pdev->dev;
1776 	INIT_WORK(&priv->reset_task, ftgmac100_reset_task);
1777 
1778 	/* map io memory */
1779 	priv->res = request_mem_region(res->start, resource_size(res),
1780 				       dev_name(&pdev->dev));
1781 	if (!priv->res) {
1782 		dev_err(&pdev->dev, "Could not reserve memory region\n");
1783 		err = -ENOMEM;
1784 		goto err_req_mem;
1785 	}
1786 
1787 	priv->base = ioremap(res->start, resource_size(res));
1788 	if (!priv->base) {
1789 		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1790 		err = -EIO;
1791 		goto err_ioremap;
1792 	}
1793 
1794 	netdev->irq = irq;
1795 
1796 	/* Enable pause */
1797 	priv->tx_pause = true;
1798 	priv->rx_pause = true;
1799 	priv->aneg_pause = true;
1800 
1801 	/* MAC address from chip or random one */
1802 	ftgmac100_initial_mac(priv);
1803 
1804 	np = pdev->dev.of_node;
1805 	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
1806 		   of_device_is_compatible(np, "aspeed,ast2500-mac") ||
1807 		   of_device_is_compatible(np, "aspeed,ast2600-mac"))) {
1808 		priv->rxdes0_edorr_mask = BIT(30);
1809 		priv->txdes0_edotr_mask = BIT(30);
1810 		priv->is_aspeed = true;
1811 	} else {
1812 		priv->rxdes0_edorr_mask = BIT(15);
1813 		priv->txdes0_edotr_mask = BIT(15);
1814 	}
1815 
1816 	if (np && of_get_property(np, "use-ncsi", NULL)) {
1817 		if (!IS_ENABLED(CONFIG_NET_NCSI)) {
1818 			dev_err(&pdev->dev, "NCSI stack not enabled\n");
1819 			goto err_ncsi_dev;
1820 		}
1821 
1822 		dev_info(&pdev->dev, "Using NCSI interface\n");
1823 		priv->use_ncsi = true;
1824 		priv->ndev = ncsi_register_dev(netdev, ftgmac100_ncsi_handler);
1825 		if (!priv->ndev)
1826 			goto err_ncsi_dev;
1827 	} else if (np && of_get_property(np, "phy-handle", NULL)) {
1828 		struct phy_device *phy;
1829 
1830 		phy = of_phy_get_and_connect(priv->netdev, np,
1831 					     &ftgmac100_adjust_link);
1832 		if (!phy) {
1833 			dev_err(&pdev->dev, "Failed to connect to phy\n");
1834 			goto err_setup_mdio;
1835 		}
1836 
1837 		/* Indicate that we support PAUSE frames (see comment in
1838 		 * Documentation/networking/phy.rst)
1839 		 */
1840 		phy_support_asym_pause(phy);
1841 
1842 		/* Display what we found */
1843 		phy_attached_info(phy);
1844 	} else if (np && !of_get_child_by_name(np, "mdio")) {
1845 		/* Support legacy ASPEED devicetree descriptions that decribe a
1846 		 * MAC with an embedded MDIO controller but have no "mdio"
1847 		 * child node. Automatically scan the MDIO bus for available
1848 		 * PHYs.
1849 		 */
1850 		priv->use_ncsi = false;
1851 		err = ftgmac100_setup_mdio(netdev);
1852 		if (err)
1853 			goto err_setup_mdio;
1854 	}
1855 
1856 	if (priv->is_aspeed)
1857 		ftgmac100_setup_clk(priv);
1858 
1859 	/* Default ring sizes */
1860 	priv->rx_q_entries = priv->new_rx_q_entries = DEF_RX_QUEUE_ENTRIES;
1861 	priv->tx_q_entries = priv->new_tx_q_entries = DEF_TX_QUEUE_ENTRIES;
1862 
1863 	/* Base feature set */
1864 	netdev->hw_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM |
1865 		NETIF_F_GRO | NETIF_F_SG | NETIF_F_HW_VLAN_CTAG_RX |
1866 		NETIF_F_HW_VLAN_CTAG_TX;
1867 
1868 	if (priv->use_ncsi)
1869 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1870 
1871 	/* AST2400  doesn't have working HW checksum generation */
1872 	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac")))
1873 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
1874 	if (np && of_get_property(np, "no-hw-checksum", NULL))
1875 		netdev->hw_features &= ~(NETIF_F_HW_CSUM | NETIF_F_RXCSUM);
1876 	netdev->features |= netdev->hw_features;
1877 
1878 	/* register network device */
1879 	err = register_netdev(netdev);
1880 	if (err) {
1881 		dev_err(&pdev->dev, "Failed to register netdev\n");
1882 		goto err_register_netdev;
1883 	}
1884 
1885 	netdev_info(netdev, "irq %d, mapped at %p\n", netdev->irq, priv->base);
1886 
1887 	return 0;
1888 
1889 err_ncsi_dev:
1890 err_register_netdev:
1891 	ftgmac100_destroy_mdio(netdev);
1892 err_setup_mdio:
1893 	iounmap(priv->base);
1894 err_ioremap:
1895 	release_resource(priv->res);
1896 err_req_mem:
1897 	free_netdev(netdev);
1898 err_alloc_etherdev:
1899 	return err;
1900 }
1901 
1902 static int ftgmac100_remove(struct platform_device *pdev)
1903 {
1904 	struct net_device *netdev;
1905 	struct ftgmac100 *priv;
1906 
1907 	netdev = platform_get_drvdata(pdev);
1908 	priv = netdev_priv(netdev);
1909 
1910 	unregister_netdev(netdev);
1911 
1912 	clk_disable_unprepare(priv->clk);
1913 
1914 	/* There's a small chance the reset task will have been re-queued,
1915 	 * during stop, make sure it's gone before we free the structure.
1916 	 */
1917 	cancel_work_sync(&priv->reset_task);
1918 
1919 	ftgmac100_destroy_mdio(netdev);
1920 
1921 	iounmap(priv->base);
1922 	release_resource(priv->res);
1923 
1924 	netif_napi_del(&priv->napi);
1925 	free_netdev(netdev);
1926 	return 0;
1927 }
1928 
1929 static const struct of_device_id ftgmac100_of_match[] = {
1930 	{ .compatible = "faraday,ftgmac100" },
1931 	{ }
1932 };
1933 MODULE_DEVICE_TABLE(of, ftgmac100_of_match);
1934 
1935 static struct platform_driver ftgmac100_driver = {
1936 	.probe	= ftgmac100_probe,
1937 	.remove	= ftgmac100_remove,
1938 	.driver	= {
1939 		.name		= DRV_NAME,
1940 		.of_match_table	= ftgmac100_of_match,
1941 	},
1942 };
1943 module_platform_driver(ftgmac100_driver);
1944 
1945 MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
1946 MODULE_DESCRIPTION("FTGMAC100 driver");
1947 MODULE_LICENSE("GPL");
1948