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 int ftgmac100_initial_mac(struct ftgmac100 *priv)
181 {
182 	u8 mac[ETH_ALEN];
183 	unsigned int m;
184 	unsigned int l;
185 	int err;
186 
187 	err = of_get_ethdev_address(priv->dev->of_node, priv->netdev);
188 	if (err == -EPROBE_DEFER)
189 		return err;
190 	if (!err) {
191 		dev_info(priv->dev, "Read MAC address %pM from device tree\n",
192 			 priv->netdev->dev_addr);
193 		return 0;
194 	}
195 
196 	m = ioread32(priv->base + FTGMAC100_OFFSET_MAC_MADR);
197 	l = ioread32(priv->base + FTGMAC100_OFFSET_MAC_LADR);
198 
199 	mac[0] = (m >> 8) & 0xff;
200 	mac[1] = m & 0xff;
201 	mac[2] = (l >> 24) & 0xff;
202 	mac[3] = (l >> 16) & 0xff;
203 	mac[4] = (l >> 8) & 0xff;
204 	mac[5] = l & 0xff;
205 
206 	if (is_valid_ether_addr(mac)) {
207 		eth_hw_addr_set(priv->netdev, mac);
208 		dev_info(priv->dev, "Read MAC address %pM from chip\n", mac);
209 	} else {
210 		eth_hw_addr_random(priv->netdev);
211 		dev_info(priv->dev, "Generated random MAC address %pM\n",
212 			 priv->netdev->dev_addr);
213 	}
214 
215 	return 0;
216 }
217 
218 static int ftgmac100_set_mac_addr(struct net_device *dev, void *p)
219 {
220 	int ret;
221 
222 	ret = eth_prepare_mac_addr_change(dev, p);
223 	if (ret < 0)
224 		return ret;
225 
226 	eth_commit_mac_addr_change(dev, p);
227 	ftgmac100_write_mac_addr(netdev_priv(dev), dev->dev_addr);
228 
229 	return 0;
230 }
231 
232 static void ftgmac100_config_pause(struct ftgmac100 *priv)
233 {
234 	u32 fcr = FTGMAC100_FCR_PAUSE_TIME(16);
235 
236 	/* Throttle tx queue when receiving pause frames */
237 	if (priv->rx_pause)
238 		fcr |= FTGMAC100_FCR_FC_EN;
239 
240 	/* Enables sending pause frames when the RX queue is past a
241 	 * certain threshold.
242 	 */
243 	if (priv->tx_pause)
244 		fcr |= FTGMAC100_FCR_FCTHR_EN;
245 
246 	iowrite32(fcr, priv->base + FTGMAC100_OFFSET_FCR);
247 }
248 
249 static void ftgmac100_init_hw(struct ftgmac100 *priv)
250 {
251 	u32 reg, rfifo_sz, tfifo_sz;
252 
253 	/* Clear stale interrupts */
254 	reg = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
255 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_ISR);
256 
257 	/* Setup RX ring buffer base */
258 	iowrite32(priv->rxdes_dma, priv->base + FTGMAC100_OFFSET_RXR_BADR);
259 
260 	/* Setup TX ring buffer base */
261 	iowrite32(priv->txdes_dma, priv->base + FTGMAC100_OFFSET_NPTXR_BADR);
262 
263 	/* Configure RX buffer size */
264 	iowrite32(FTGMAC100_RBSR_SIZE(RX_BUF_SIZE),
265 		  priv->base + FTGMAC100_OFFSET_RBSR);
266 
267 	/* Set RX descriptor autopoll */
268 	iowrite32(FTGMAC100_APTC_RXPOLL_CNT(1),
269 		  priv->base + FTGMAC100_OFFSET_APTC);
270 
271 	/* Write MAC address */
272 	ftgmac100_write_mac_addr(priv, priv->netdev->dev_addr);
273 
274 	/* Write multicast filter */
275 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
276 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
277 
278 	/* Configure descriptor sizes and increase burst sizes according
279 	 * to values in Aspeed SDK. The FIFO arbitration is enabled and
280 	 * the thresholds set based on the recommended values in the
281 	 * AST2400 specification.
282 	 */
283 	iowrite32(FTGMAC100_DBLAC_RXDES_SIZE(2) |   /* 2*8 bytes RX descs */
284 		  FTGMAC100_DBLAC_TXDES_SIZE(2) |   /* 2*8 bytes TX descs */
285 		  FTGMAC100_DBLAC_RXBURST_SIZE(3) | /* 512 bytes max RX bursts */
286 		  FTGMAC100_DBLAC_TXBURST_SIZE(3) | /* 512 bytes max TX bursts */
287 		  FTGMAC100_DBLAC_RX_THR_EN |       /* Enable fifo threshold arb */
288 		  FTGMAC100_DBLAC_RXFIFO_HTHR(6) |  /* 6/8 of FIFO high threshold */
289 		  FTGMAC100_DBLAC_RXFIFO_LTHR(2),   /* 2/8 of FIFO low threshold */
290 		  priv->base + FTGMAC100_OFFSET_DBLAC);
291 
292 	/* Interrupt mitigation configured for 1 interrupt/packet. HW interrupt
293 	 * mitigation doesn't seem to provide any benefit with NAPI so leave
294 	 * it at that.
295 	 */
296 	iowrite32(FTGMAC100_ITC_RXINT_THR(1) |
297 		  FTGMAC100_ITC_TXINT_THR(1),
298 		  priv->base + FTGMAC100_OFFSET_ITC);
299 
300 	/* Configure FIFO sizes in the TPAFCR register */
301 	reg = ioread32(priv->base + FTGMAC100_OFFSET_FEAR);
302 	rfifo_sz = reg & 0x00000007;
303 	tfifo_sz = (reg >> 3) & 0x00000007;
304 	reg = ioread32(priv->base + FTGMAC100_OFFSET_TPAFCR);
305 	reg &= ~0x3f000000;
306 	reg |= (tfifo_sz << 27);
307 	reg |= (rfifo_sz << 24);
308 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_TPAFCR);
309 }
310 
311 static void ftgmac100_start_hw(struct ftgmac100 *priv)
312 {
313 	u32 maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
314 
315 	/* Keep the original GMAC and FAST bits */
316 	maccr &= (FTGMAC100_MACCR_FAST_MODE | FTGMAC100_MACCR_GIGA_MODE);
317 
318 	/* Add all the main enable bits */
319 	maccr |= FTGMAC100_MACCR_TXDMA_EN	|
320 		 FTGMAC100_MACCR_RXDMA_EN	|
321 		 FTGMAC100_MACCR_TXMAC_EN	|
322 		 FTGMAC100_MACCR_RXMAC_EN	|
323 		 FTGMAC100_MACCR_CRC_APD	|
324 		 FTGMAC100_MACCR_PHY_LINK_LEVEL	|
325 		 FTGMAC100_MACCR_RX_RUNT	|
326 		 FTGMAC100_MACCR_RX_BROADPKT;
327 
328 	/* Add other bits as needed */
329 	if (priv->cur_duplex == DUPLEX_FULL)
330 		maccr |= FTGMAC100_MACCR_FULLDUP;
331 	if (priv->netdev->flags & IFF_PROMISC)
332 		maccr |= FTGMAC100_MACCR_RX_ALL;
333 	if (priv->netdev->flags & IFF_ALLMULTI)
334 		maccr |= FTGMAC100_MACCR_RX_MULTIPKT;
335 	else if (netdev_mc_count(priv->netdev))
336 		maccr |= FTGMAC100_MACCR_HT_MULTI_EN;
337 
338 	/* Vlan filtering enabled */
339 	if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
340 		maccr |= FTGMAC100_MACCR_RM_VLAN;
341 
342 	/* Hit the HW */
343 	iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
344 }
345 
346 static void ftgmac100_stop_hw(struct ftgmac100 *priv)
347 {
348 	iowrite32(0, priv->base + FTGMAC100_OFFSET_MACCR);
349 }
350 
351 static void ftgmac100_calc_mc_hash(struct ftgmac100 *priv)
352 {
353 	struct netdev_hw_addr *ha;
354 
355 	priv->maht1 = 0;
356 	priv->maht0 = 0;
357 	netdev_for_each_mc_addr(ha, priv->netdev) {
358 		u32 crc_val = ether_crc_le(ETH_ALEN, ha->addr);
359 
360 		crc_val = (~(crc_val >> 2)) & 0x3f;
361 		if (crc_val >= 32)
362 			priv->maht1 |= 1ul << (crc_val - 32);
363 		else
364 			priv->maht0 |= 1ul << (crc_val);
365 	}
366 }
367 
368 static void ftgmac100_set_rx_mode(struct net_device *netdev)
369 {
370 	struct ftgmac100 *priv = netdev_priv(netdev);
371 
372 	/* Setup the hash filter */
373 	ftgmac100_calc_mc_hash(priv);
374 
375 	/* Interface down ? that's all there is to do */
376 	if (!netif_running(netdev))
377 		return;
378 
379 	/* Update the HW */
380 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
381 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
382 
383 	/* Reconfigure MACCR */
384 	ftgmac100_start_hw(priv);
385 }
386 
387 static int ftgmac100_alloc_rx_buf(struct ftgmac100 *priv, unsigned int entry,
388 				  struct ftgmac100_rxdes *rxdes, gfp_t gfp)
389 {
390 	struct net_device *netdev = priv->netdev;
391 	struct sk_buff *skb;
392 	dma_addr_t map;
393 	int err = 0;
394 
395 	skb = netdev_alloc_skb_ip_align(netdev, RX_BUF_SIZE);
396 	if (unlikely(!skb)) {
397 		if (net_ratelimit())
398 			netdev_warn(netdev, "failed to allocate rx skb\n");
399 		err = -ENOMEM;
400 		map = priv->rx_scratch_dma;
401 	} else {
402 		map = dma_map_single(priv->dev, skb->data, RX_BUF_SIZE,
403 				     DMA_FROM_DEVICE);
404 		if (unlikely(dma_mapping_error(priv->dev, map))) {
405 			if (net_ratelimit())
406 				netdev_err(netdev, "failed to map rx page\n");
407 			dev_kfree_skb_any(skb);
408 			map = priv->rx_scratch_dma;
409 			skb = NULL;
410 			err = -ENOMEM;
411 		}
412 	}
413 
414 	/* Store skb */
415 	priv->rx_skbs[entry] = skb;
416 
417 	/* Store DMA address into RX desc */
418 	rxdes->rxdes3 = cpu_to_le32(map);
419 
420 	/* Ensure the above is ordered vs clearing the OWN bit */
421 	dma_wmb();
422 
423 	/* Clean status (which resets own bit) */
424 	if (entry == (priv->rx_q_entries - 1))
425 		rxdes->rxdes0 = cpu_to_le32(priv->rxdes0_edorr_mask);
426 	else
427 		rxdes->rxdes0 = 0;
428 
429 	return err;
430 }
431 
432 static unsigned int ftgmac100_next_rx_pointer(struct ftgmac100 *priv,
433 					      unsigned int pointer)
434 {
435 	return (pointer + 1) & (priv->rx_q_entries - 1);
436 }
437 
438 static void ftgmac100_rx_packet_error(struct ftgmac100 *priv, u32 status)
439 {
440 	struct net_device *netdev = priv->netdev;
441 
442 	if (status & FTGMAC100_RXDES0_RX_ERR)
443 		netdev->stats.rx_errors++;
444 
445 	if (status & FTGMAC100_RXDES0_CRC_ERR)
446 		netdev->stats.rx_crc_errors++;
447 
448 	if (status & (FTGMAC100_RXDES0_FTL |
449 		      FTGMAC100_RXDES0_RUNT |
450 		      FTGMAC100_RXDES0_RX_ODD_NB))
451 		netdev->stats.rx_length_errors++;
452 }
453 
454 static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed)
455 {
456 	struct net_device *netdev = priv->netdev;
457 	struct ftgmac100_rxdes *rxdes;
458 	struct sk_buff *skb;
459 	unsigned int pointer, size;
460 	u32 status, csum_vlan;
461 	dma_addr_t map;
462 
463 	/* Grab next RX descriptor */
464 	pointer = priv->rx_pointer;
465 	rxdes = &priv->rxdes[pointer];
466 
467 	/* Grab descriptor status */
468 	status = le32_to_cpu(rxdes->rxdes0);
469 
470 	/* Do we have a packet ? */
471 	if (!(status & FTGMAC100_RXDES0_RXPKT_RDY))
472 		return false;
473 
474 	/* Order subsequent reads with the test for the ready bit */
475 	dma_rmb();
476 
477 	/* We don't cope with fragmented RX packets */
478 	if (unlikely(!(status & FTGMAC100_RXDES0_FRS) ||
479 		     !(status & FTGMAC100_RXDES0_LRS)))
480 		goto drop;
481 
482 	/* Grab received size and csum vlan field in the descriptor */
483 	size = status & FTGMAC100_RXDES0_VDBC;
484 	csum_vlan = le32_to_cpu(rxdes->rxdes1);
485 
486 	/* Any error (other than csum offload) flagged ? */
487 	if (unlikely(status & RXDES0_ANY_ERROR)) {
488 		/* Correct for incorrect flagging of runt packets
489 		 * with vlan tags... Just accept a runt packet that
490 		 * has been flagged as vlan and whose size is at
491 		 * least 60 bytes.
492 		 */
493 		if ((status & FTGMAC100_RXDES0_RUNT) &&
494 		    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL) &&
495 		    (size >= 60))
496 			status &= ~FTGMAC100_RXDES0_RUNT;
497 
498 		/* Any error still in there ? */
499 		if (status & RXDES0_ANY_ERROR) {
500 			ftgmac100_rx_packet_error(priv, status);
501 			goto drop;
502 		}
503 	}
504 
505 	/* If the packet had no skb (failed to allocate earlier)
506 	 * then try to allocate one and skip
507 	 */
508 	skb = priv->rx_skbs[pointer];
509 	if (!unlikely(skb)) {
510 		ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
511 		goto drop;
512 	}
513 
514 	if (unlikely(status & FTGMAC100_RXDES0_MULTICAST))
515 		netdev->stats.multicast++;
516 
517 	/* If the HW found checksum errors, bounce it to software.
518 	 *
519 	 * If we didn't, we need to see if the packet was recognized
520 	 * by HW as one of the supported checksummed protocols before
521 	 * we accept the HW test results.
522 	 */
523 	if (netdev->features & NETIF_F_RXCSUM) {
524 		u32 err_bits = FTGMAC100_RXDES1_TCP_CHKSUM_ERR |
525 			FTGMAC100_RXDES1_UDP_CHKSUM_ERR |
526 			FTGMAC100_RXDES1_IP_CHKSUM_ERR;
527 		if ((csum_vlan & err_bits) ||
528 		    !(csum_vlan & FTGMAC100_RXDES1_PROT_MASK))
529 			skb->ip_summed = CHECKSUM_NONE;
530 		else
531 			skb->ip_summed = CHECKSUM_UNNECESSARY;
532 	}
533 
534 	/* Transfer received size to skb */
535 	skb_put(skb, size);
536 
537 	/* Extract vlan tag */
538 	if ((netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
539 	    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL))
540 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
541 				       csum_vlan & 0xffff);
542 
543 	/* Tear down DMA mapping, do necessary cache management */
544 	map = le32_to_cpu(rxdes->rxdes3);
545 
546 #if defined(CONFIG_ARM) && !defined(CONFIG_ARM_DMA_USE_IOMMU)
547 	/* When we don't have an iommu, we can save cycles by not
548 	 * invalidating the cache for the part of the packet that
549 	 * wasn't received.
550 	 */
551 	dma_unmap_single(priv->dev, map, size, DMA_FROM_DEVICE);
552 #else
553 	dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
554 #endif
555 
556 
557 	/* Resplenish rx ring */
558 	ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
559 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
560 
561 	skb->protocol = eth_type_trans(skb, netdev);
562 
563 	netdev->stats.rx_packets++;
564 	netdev->stats.rx_bytes += size;
565 
566 	/* push packet to protocol stack */
567 	if (skb->ip_summed == CHECKSUM_NONE)
568 		netif_receive_skb(skb);
569 	else
570 		napi_gro_receive(&priv->napi, skb);
571 
572 	(*processed)++;
573 	return true;
574 
575 drop:
576 	/* Clean rxdes0 (which resets own bit) */
577 	rxdes->rxdes0 = cpu_to_le32(status & priv->rxdes0_edorr_mask);
578 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
579 	netdev->stats.rx_dropped++;
580 	return true;
581 }
582 
583 static u32 ftgmac100_base_tx_ctlstat(struct ftgmac100 *priv,
584 				     unsigned int index)
585 {
586 	if (index == (priv->tx_q_entries - 1))
587 		return priv->txdes0_edotr_mask;
588 	else
589 		return 0;
590 }
591 
592 static unsigned int ftgmac100_next_tx_pointer(struct ftgmac100 *priv,
593 					      unsigned int pointer)
594 {
595 	return (pointer + 1) & (priv->tx_q_entries - 1);
596 }
597 
598 static u32 ftgmac100_tx_buf_avail(struct ftgmac100 *priv)
599 {
600 	/* Returns the number of available slots in the TX queue
601 	 *
602 	 * This always leaves one free slot so we don't have to
603 	 * worry about empty vs. full, and this simplifies the
604 	 * test for ftgmac100_tx_buf_cleanable() below
605 	 */
606 	return (priv->tx_clean_pointer - priv->tx_pointer - 1) &
607 		(priv->tx_q_entries - 1);
608 }
609 
610 static bool ftgmac100_tx_buf_cleanable(struct ftgmac100 *priv)
611 {
612 	return priv->tx_pointer != priv->tx_clean_pointer;
613 }
614 
615 static void ftgmac100_free_tx_packet(struct ftgmac100 *priv,
616 				     unsigned int pointer,
617 				     struct sk_buff *skb,
618 				     struct ftgmac100_txdes *txdes,
619 				     u32 ctl_stat)
620 {
621 	dma_addr_t map = le32_to_cpu(txdes->txdes3);
622 	size_t len;
623 
624 	if (ctl_stat & FTGMAC100_TXDES0_FTS) {
625 		len = skb_headlen(skb);
626 		dma_unmap_single(priv->dev, map, len, DMA_TO_DEVICE);
627 	} else {
628 		len = FTGMAC100_TXDES0_TXBUF_SIZE(ctl_stat);
629 		dma_unmap_page(priv->dev, map, len, DMA_TO_DEVICE);
630 	}
631 
632 	/* Free SKB on last segment */
633 	if (ctl_stat & FTGMAC100_TXDES0_LTS)
634 		dev_kfree_skb(skb);
635 	priv->tx_skbs[pointer] = NULL;
636 }
637 
638 static bool ftgmac100_tx_complete_packet(struct ftgmac100 *priv)
639 {
640 	struct net_device *netdev = priv->netdev;
641 	struct ftgmac100_txdes *txdes;
642 	struct sk_buff *skb;
643 	unsigned int pointer;
644 	u32 ctl_stat;
645 
646 	pointer = priv->tx_clean_pointer;
647 	txdes = &priv->txdes[pointer];
648 
649 	ctl_stat = le32_to_cpu(txdes->txdes0);
650 	if (ctl_stat & FTGMAC100_TXDES0_TXDMA_OWN)
651 		return false;
652 
653 	skb = priv->tx_skbs[pointer];
654 	netdev->stats.tx_packets++;
655 	netdev->stats.tx_bytes += skb->len;
656 	ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
657 	txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
658 
659 	/* Ensure the descriptor config is visible before setting the tx
660 	 * pointer.
661 	 */
662 	smp_wmb();
663 
664 	priv->tx_clean_pointer = ftgmac100_next_tx_pointer(priv, pointer);
665 
666 	return true;
667 }
668 
669 static void ftgmac100_tx_complete(struct ftgmac100 *priv)
670 {
671 	struct net_device *netdev = priv->netdev;
672 
673 	/* Process all completed packets */
674 	while (ftgmac100_tx_buf_cleanable(priv) &&
675 	       ftgmac100_tx_complete_packet(priv))
676 		;
677 
678 	/* Restart queue if needed */
679 	smp_mb();
680 	if (unlikely(netif_queue_stopped(netdev) &&
681 		     ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)) {
682 		struct netdev_queue *txq;
683 
684 		txq = netdev_get_tx_queue(netdev, 0);
685 		__netif_tx_lock(txq, smp_processor_id());
686 		if (netif_queue_stopped(netdev) &&
687 		    ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
688 			netif_wake_queue(netdev);
689 		__netif_tx_unlock(txq);
690 	}
691 }
692 
693 static bool ftgmac100_prep_tx_csum(struct sk_buff *skb, u32 *csum_vlan)
694 {
695 	if (skb->protocol == cpu_to_be16(ETH_P_IP)) {
696 		u8 ip_proto = ip_hdr(skb)->protocol;
697 
698 		*csum_vlan |= FTGMAC100_TXDES1_IP_CHKSUM;
699 		switch(ip_proto) {
700 		case IPPROTO_TCP:
701 			*csum_vlan |= FTGMAC100_TXDES1_TCP_CHKSUM;
702 			return true;
703 		case IPPROTO_UDP:
704 			*csum_vlan |= FTGMAC100_TXDES1_UDP_CHKSUM;
705 			return true;
706 		case IPPROTO_IP:
707 			return true;
708 		}
709 	}
710 	return skb_checksum_help(skb) == 0;
711 }
712 
713 static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb,
714 					     struct net_device *netdev)
715 {
716 	struct ftgmac100 *priv = netdev_priv(netdev);
717 	struct ftgmac100_txdes *txdes, *first;
718 	unsigned int pointer, nfrags, len, i, j;
719 	u32 f_ctl_stat, ctl_stat, csum_vlan;
720 	dma_addr_t map;
721 
722 	/* The HW doesn't pad small frames */
723 	if (eth_skb_pad(skb)) {
724 		netdev->stats.tx_dropped++;
725 		return NETDEV_TX_OK;
726 	}
727 
728 	/* Reject oversize packets */
729 	if (unlikely(skb->len > MAX_PKT_SIZE)) {
730 		if (net_ratelimit())
731 			netdev_dbg(netdev, "tx packet too big\n");
732 		goto drop;
733 	}
734 
735 	/* Do we have a limit on #fragments ? I yet have to get a reply
736 	 * from Aspeed. If there's one I haven't hit it.
737 	 */
738 	nfrags = skb_shinfo(skb)->nr_frags;
739 
740 	/* Setup HW checksumming */
741 	csum_vlan = 0;
742 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
743 	    !ftgmac100_prep_tx_csum(skb, &csum_vlan))
744 		goto drop;
745 
746 	/* Add VLAN tag */
747 	if (skb_vlan_tag_present(skb)) {
748 		csum_vlan |= FTGMAC100_TXDES1_INS_VLANTAG;
749 		csum_vlan |= skb_vlan_tag_get(skb) & 0xffff;
750 	}
751 
752 	/* Get header len */
753 	len = skb_headlen(skb);
754 
755 	/* Map the packet head */
756 	map = dma_map_single(priv->dev, skb->data, len, DMA_TO_DEVICE);
757 	if (dma_mapping_error(priv->dev, map)) {
758 		if (net_ratelimit())
759 			netdev_err(netdev, "map tx packet head failed\n");
760 		goto drop;
761 	}
762 
763 	/* Grab the next free tx descriptor */
764 	pointer = priv->tx_pointer;
765 	txdes = first = &priv->txdes[pointer];
766 
767 	/* Setup it up with the packet head. Don't write the head to the
768 	 * ring just yet
769 	 */
770 	priv->tx_skbs[pointer] = skb;
771 	f_ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
772 	f_ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
773 	f_ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
774 	f_ctl_stat |= FTGMAC100_TXDES0_FTS;
775 	if (nfrags == 0)
776 		f_ctl_stat |= FTGMAC100_TXDES0_LTS;
777 	txdes->txdes3 = cpu_to_le32(map);
778 	txdes->txdes1 = cpu_to_le32(csum_vlan);
779 
780 	/* Next descriptor */
781 	pointer = ftgmac100_next_tx_pointer(priv, pointer);
782 
783 	/* Add the fragments */
784 	for (i = 0; i < nfrags; i++) {
785 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
786 
787 		len = skb_frag_size(frag);
788 
789 		/* Map it */
790 		map = skb_frag_dma_map(priv->dev, frag, 0, len,
791 				       DMA_TO_DEVICE);
792 		if (dma_mapping_error(priv->dev, map))
793 			goto dma_err;
794 
795 		/* Setup descriptor */
796 		priv->tx_skbs[pointer] = skb;
797 		txdes = &priv->txdes[pointer];
798 		ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
799 		ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
800 		ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
801 		if (i == (nfrags - 1))
802 			ctl_stat |= FTGMAC100_TXDES0_LTS;
803 		txdes->txdes0 = cpu_to_le32(ctl_stat);
804 		txdes->txdes1 = 0;
805 		txdes->txdes3 = cpu_to_le32(map);
806 
807 		/* Next one */
808 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
809 	}
810 
811 	/* Order the previous packet and descriptor udpates
812 	 * before setting the OWN bit on the first descriptor.
813 	 */
814 	dma_wmb();
815 	first->txdes0 = cpu_to_le32(f_ctl_stat);
816 
817 	/* Ensure the descriptor config is visible before setting the tx
818 	 * pointer.
819 	 */
820 	smp_wmb();
821 
822 	/* Update next TX pointer */
823 	priv->tx_pointer = pointer;
824 
825 	/* If there isn't enough room for all the fragments of a new packet
826 	 * in the TX ring, stop the queue. The sequence below is race free
827 	 * vs. a concurrent restart in ftgmac100_poll()
828 	 */
829 	if (unlikely(ftgmac100_tx_buf_avail(priv) < TX_THRESHOLD)) {
830 		netif_stop_queue(netdev);
831 		/* Order the queue stop with the test below */
832 		smp_mb();
833 		if (ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
834 			netif_wake_queue(netdev);
835 	}
836 
837 	/* Poke transmitter to read the updated TX descriptors */
838 	iowrite32(1, priv->base + FTGMAC100_OFFSET_NPTXPD);
839 
840 	return NETDEV_TX_OK;
841 
842 dma_err:
843 	if (net_ratelimit())
844 		netdev_err(netdev, "map tx fragment failed\n");
845 
846 	/* Free head */
847 	pointer = priv->tx_pointer;
848 	ftgmac100_free_tx_packet(priv, pointer, skb, first, f_ctl_stat);
849 	first->txdes0 = cpu_to_le32(f_ctl_stat & priv->txdes0_edotr_mask);
850 
851 	/* Then all fragments */
852 	for (j = 0; j < i; j++) {
853 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
854 		txdes = &priv->txdes[pointer];
855 		ctl_stat = le32_to_cpu(txdes->txdes0);
856 		ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
857 		txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
858 	}
859 
860 	/* This cannot be reached if we successfully mapped the
861 	 * last fragment, so we know ftgmac100_free_tx_packet()
862 	 * hasn't freed the skb yet.
863 	 */
864 drop:
865 	/* Drop the packet */
866 	dev_kfree_skb_any(skb);
867 	netdev->stats.tx_dropped++;
868 
869 	return NETDEV_TX_OK;
870 }
871 
872 static void ftgmac100_free_buffers(struct ftgmac100 *priv)
873 {
874 	int i;
875 
876 	/* Free all RX buffers */
877 	for (i = 0; i < priv->rx_q_entries; i++) {
878 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
879 		struct sk_buff *skb = priv->rx_skbs[i];
880 		dma_addr_t map = le32_to_cpu(rxdes->rxdes3);
881 
882 		if (!skb)
883 			continue;
884 
885 		priv->rx_skbs[i] = NULL;
886 		dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
887 		dev_kfree_skb_any(skb);
888 	}
889 
890 	/* Free all TX buffers */
891 	for (i = 0; i < priv->tx_q_entries; i++) {
892 		struct ftgmac100_txdes *txdes = &priv->txdes[i];
893 		struct sk_buff *skb = priv->tx_skbs[i];
894 
895 		if (!skb)
896 			continue;
897 		ftgmac100_free_tx_packet(priv, i, skb, txdes,
898 					 le32_to_cpu(txdes->txdes0));
899 	}
900 }
901 
902 static void ftgmac100_free_rings(struct ftgmac100 *priv)
903 {
904 	/* Free skb arrays */
905 	kfree(priv->rx_skbs);
906 	kfree(priv->tx_skbs);
907 
908 	/* Free descriptors */
909 	if (priv->rxdes)
910 		dma_free_coherent(priv->dev, MAX_RX_QUEUE_ENTRIES *
911 				  sizeof(struct ftgmac100_rxdes),
912 				  priv->rxdes, priv->rxdes_dma);
913 	priv->rxdes = NULL;
914 
915 	if (priv->txdes)
916 		dma_free_coherent(priv->dev, MAX_TX_QUEUE_ENTRIES *
917 				  sizeof(struct ftgmac100_txdes),
918 				  priv->txdes, priv->txdes_dma);
919 	priv->txdes = NULL;
920 
921 	/* Free scratch packet buffer */
922 	if (priv->rx_scratch)
923 		dma_free_coherent(priv->dev, RX_BUF_SIZE,
924 				  priv->rx_scratch, priv->rx_scratch_dma);
925 }
926 
927 static int ftgmac100_alloc_rings(struct ftgmac100 *priv)
928 {
929 	/* Allocate skb arrays */
930 	priv->rx_skbs = kcalloc(MAX_RX_QUEUE_ENTRIES, sizeof(void *),
931 				GFP_KERNEL);
932 	if (!priv->rx_skbs)
933 		return -ENOMEM;
934 	priv->tx_skbs = kcalloc(MAX_TX_QUEUE_ENTRIES, sizeof(void *),
935 				GFP_KERNEL);
936 	if (!priv->tx_skbs)
937 		return -ENOMEM;
938 
939 	/* Allocate descriptors */
940 	priv->rxdes = dma_alloc_coherent(priv->dev,
941 					 MAX_RX_QUEUE_ENTRIES * sizeof(struct ftgmac100_rxdes),
942 					 &priv->rxdes_dma, GFP_KERNEL);
943 	if (!priv->rxdes)
944 		return -ENOMEM;
945 	priv->txdes = dma_alloc_coherent(priv->dev,
946 					 MAX_TX_QUEUE_ENTRIES * sizeof(struct ftgmac100_txdes),
947 					 &priv->txdes_dma, GFP_KERNEL);
948 	if (!priv->txdes)
949 		return -ENOMEM;
950 
951 	/* Allocate scratch packet buffer */
952 	priv->rx_scratch = dma_alloc_coherent(priv->dev,
953 					      RX_BUF_SIZE,
954 					      &priv->rx_scratch_dma,
955 					      GFP_KERNEL);
956 	if (!priv->rx_scratch)
957 		return -ENOMEM;
958 
959 	return 0;
960 }
961 
962 static void ftgmac100_init_rings(struct ftgmac100 *priv)
963 {
964 	struct ftgmac100_rxdes *rxdes = NULL;
965 	struct ftgmac100_txdes *txdes = NULL;
966 	int i;
967 
968 	/* Update entries counts */
969 	priv->rx_q_entries = priv->new_rx_q_entries;
970 	priv->tx_q_entries = priv->new_tx_q_entries;
971 
972 	if (WARN_ON(priv->rx_q_entries < MIN_RX_QUEUE_ENTRIES))
973 		return;
974 
975 	/* Initialize RX ring */
976 	for (i = 0; i < priv->rx_q_entries; i++) {
977 		rxdes = &priv->rxdes[i];
978 		rxdes->rxdes0 = 0;
979 		rxdes->rxdes3 = cpu_to_le32(priv->rx_scratch_dma);
980 	}
981 	/* Mark the end of the ring */
982 	rxdes->rxdes0 |= cpu_to_le32(priv->rxdes0_edorr_mask);
983 
984 	if (WARN_ON(priv->tx_q_entries < MIN_RX_QUEUE_ENTRIES))
985 		return;
986 
987 	/* Initialize TX ring */
988 	for (i = 0; i < priv->tx_q_entries; i++) {
989 		txdes = &priv->txdes[i];
990 		txdes->txdes0 = 0;
991 	}
992 	txdes->txdes0 |= cpu_to_le32(priv->txdes0_edotr_mask);
993 }
994 
995 static int ftgmac100_alloc_rx_buffers(struct ftgmac100 *priv)
996 {
997 	int i;
998 
999 	for (i = 0; i < priv->rx_q_entries; i++) {
1000 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
1001 
1002 		if (ftgmac100_alloc_rx_buf(priv, i, rxdes, GFP_KERNEL))
1003 			return -ENOMEM;
1004 	}
1005 	return 0;
1006 }
1007 
1008 static int ftgmac100_mdiobus_read(struct mii_bus *bus, int phy_addr, int regnum)
1009 {
1010 	struct net_device *netdev = bus->priv;
1011 	struct ftgmac100 *priv = netdev_priv(netdev);
1012 	unsigned int phycr;
1013 	int i;
1014 
1015 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1016 
1017 	/* preserve MDC cycle threshold */
1018 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1019 
1020 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1021 		 FTGMAC100_PHYCR_REGAD(regnum) |
1022 		 FTGMAC100_PHYCR_MIIRD;
1023 
1024 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1025 
1026 	for (i = 0; i < 10; i++) {
1027 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1028 
1029 		if ((phycr & FTGMAC100_PHYCR_MIIRD) == 0) {
1030 			int data;
1031 
1032 			data = ioread32(priv->base + FTGMAC100_OFFSET_PHYDATA);
1033 			return FTGMAC100_PHYDATA_MIIRDATA(data);
1034 		}
1035 
1036 		udelay(100);
1037 	}
1038 
1039 	netdev_err(netdev, "mdio read timed out\n");
1040 	return -EIO;
1041 }
1042 
1043 static int ftgmac100_mdiobus_write(struct mii_bus *bus, int phy_addr,
1044 				   int regnum, u16 value)
1045 {
1046 	struct net_device *netdev = bus->priv;
1047 	struct ftgmac100 *priv = netdev_priv(netdev);
1048 	unsigned int phycr;
1049 	int data;
1050 	int i;
1051 
1052 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1053 
1054 	/* preserve MDC cycle threshold */
1055 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1056 
1057 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1058 		 FTGMAC100_PHYCR_REGAD(regnum) |
1059 		 FTGMAC100_PHYCR_MIIWR;
1060 
1061 	data = FTGMAC100_PHYDATA_MIIWDATA(value);
1062 
1063 	iowrite32(data, priv->base + FTGMAC100_OFFSET_PHYDATA);
1064 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1065 
1066 	for (i = 0; i < 10; i++) {
1067 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1068 
1069 		if ((phycr & FTGMAC100_PHYCR_MIIWR) == 0)
1070 			return 0;
1071 
1072 		udelay(100);
1073 	}
1074 
1075 	netdev_err(netdev, "mdio write timed out\n");
1076 	return -EIO;
1077 }
1078 
1079 static void ftgmac100_get_drvinfo(struct net_device *netdev,
1080 				  struct ethtool_drvinfo *info)
1081 {
1082 	strscpy(info->driver, DRV_NAME, sizeof(info->driver));
1083 	strscpy(info->bus_info, dev_name(&netdev->dev), sizeof(info->bus_info));
1084 }
1085 
1086 static void
1087 ftgmac100_get_ringparam(struct net_device *netdev,
1088 			struct ethtool_ringparam *ering,
1089 			struct kernel_ethtool_ringparam *kernel_ering,
1090 			struct netlink_ext_ack *extack)
1091 {
1092 	struct ftgmac100 *priv = netdev_priv(netdev);
1093 
1094 	memset(ering, 0, sizeof(*ering));
1095 	ering->rx_max_pending = MAX_RX_QUEUE_ENTRIES;
1096 	ering->tx_max_pending = MAX_TX_QUEUE_ENTRIES;
1097 	ering->rx_pending = priv->rx_q_entries;
1098 	ering->tx_pending = priv->tx_q_entries;
1099 }
1100 
1101 static int
1102 ftgmac100_set_ringparam(struct net_device *netdev,
1103 			struct ethtool_ringparam *ering,
1104 			struct kernel_ethtool_ringparam *kernel_ering,
1105 			struct netlink_ext_ack *extack)
1106 {
1107 	struct ftgmac100 *priv = netdev_priv(netdev);
1108 
1109 	if (ering->rx_pending > MAX_RX_QUEUE_ENTRIES ||
1110 	    ering->tx_pending > MAX_TX_QUEUE_ENTRIES ||
1111 	    ering->rx_pending < MIN_RX_QUEUE_ENTRIES ||
1112 	    ering->tx_pending < MIN_TX_QUEUE_ENTRIES ||
1113 	    !is_power_of_2(ering->rx_pending) ||
1114 	    !is_power_of_2(ering->tx_pending))
1115 		return -EINVAL;
1116 
1117 	priv->new_rx_q_entries = ering->rx_pending;
1118 	priv->new_tx_q_entries = ering->tx_pending;
1119 	if (netif_running(netdev))
1120 		schedule_work(&priv->reset_task);
1121 
1122 	return 0;
1123 }
1124 
1125 static void ftgmac100_get_pauseparam(struct net_device *netdev,
1126 				     struct ethtool_pauseparam *pause)
1127 {
1128 	struct ftgmac100 *priv = netdev_priv(netdev);
1129 
1130 	pause->autoneg = priv->aneg_pause;
1131 	pause->tx_pause = priv->tx_pause;
1132 	pause->rx_pause = priv->rx_pause;
1133 }
1134 
1135 static int ftgmac100_set_pauseparam(struct net_device *netdev,
1136 				    struct ethtool_pauseparam *pause)
1137 {
1138 	struct ftgmac100 *priv = netdev_priv(netdev);
1139 	struct phy_device *phydev = netdev->phydev;
1140 
1141 	priv->aneg_pause = pause->autoneg;
1142 	priv->tx_pause = pause->tx_pause;
1143 	priv->rx_pause = pause->rx_pause;
1144 
1145 	if (phydev)
1146 		phy_set_asym_pause(phydev, pause->rx_pause, pause->tx_pause);
1147 
1148 	if (netif_running(netdev)) {
1149 		if (!(phydev && priv->aneg_pause))
1150 			ftgmac100_config_pause(priv);
1151 	}
1152 
1153 	return 0;
1154 }
1155 
1156 static const struct ethtool_ops ftgmac100_ethtool_ops = {
1157 	.get_drvinfo		= ftgmac100_get_drvinfo,
1158 	.get_link		= ethtool_op_get_link,
1159 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1160 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1161 	.nway_reset		= phy_ethtool_nway_reset,
1162 	.get_ringparam		= ftgmac100_get_ringparam,
1163 	.set_ringparam		= ftgmac100_set_ringparam,
1164 	.get_pauseparam		= ftgmac100_get_pauseparam,
1165 	.set_pauseparam		= ftgmac100_set_pauseparam,
1166 };
1167 
1168 static irqreturn_t ftgmac100_interrupt(int irq, void *dev_id)
1169 {
1170 	struct net_device *netdev = dev_id;
1171 	struct ftgmac100 *priv = netdev_priv(netdev);
1172 	unsigned int status, new_mask = FTGMAC100_INT_BAD;
1173 
1174 	/* Fetch and clear interrupt bits, process abnormal ones */
1175 	status = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
1176 	iowrite32(status, priv->base + FTGMAC100_OFFSET_ISR);
1177 	if (unlikely(status & FTGMAC100_INT_BAD)) {
1178 
1179 		/* RX buffer unavailable */
1180 		if (status & FTGMAC100_INT_NO_RXBUF)
1181 			netdev->stats.rx_over_errors++;
1182 
1183 		/* received packet lost due to RX FIFO full */
1184 		if (status & FTGMAC100_INT_RPKT_LOST)
1185 			netdev->stats.rx_fifo_errors++;
1186 
1187 		/* sent packet lost due to excessive TX collision */
1188 		if (status & FTGMAC100_INT_XPKT_LOST)
1189 			netdev->stats.tx_fifo_errors++;
1190 
1191 		/* AHB error -> Reset the chip */
1192 		if (status & FTGMAC100_INT_AHB_ERR) {
1193 			if (net_ratelimit())
1194 				netdev_warn(netdev,
1195 					   "AHB bus error ! Resetting chip.\n");
1196 			iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1197 			schedule_work(&priv->reset_task);
1198 			return IRQ_HANDLED;
1199 		}
1200 
1201 		/* We may need to restart the MAC after such errors, delay
1202 		 * this until after we have freed some Rx buffers though
1203 		 */
1204 		priv->need_mac_restart = true;
1205 
1206 		/* Disable those errors until we restart */
1207 		new_mask &= ~status;
1208 	}
1209 
1210 	/* Only enable "bad" interrupts while NAPI is on */
1211 	iowrite32(new_mask, priv->base + FTGMAC100_OFFSET_IER);
1212 
1213 	/* Schedule NAPI bh */
1214 	napi_schedule_irqoff(&priv->napi);
1215 
1216 	return IRQ_HANDLED;
1217 }
1218 
1219 static bool ftgmac100_check_rx(struct ftgmac100 *priv)
1220 {
1221 	struct ftgmac100_rxdes *rxdes = &priv->rxdes[priv->rx_pointer];
1222 
1223 	/* Do we have a packet ? */
1224 	return !!(rxdes->rxdes0 & cpu_to_le32(FTGMAC100_RXDES0_RXPKT_RDY));
1225 }
1226 
1227 static int ftgmac100_poll(struct napi_struct *napi, int budget)
1228 {
1229 	struct ftgmac100 *priv = container_of(napi, struct ftgmac100, napi);
1230 	int work_done = 0;
1231 	bool more;
1232 
1233 	/* Handle TX completions */
1234 	if (ftgmac100_tx_buf_cleanable(priv))
1235 		ftgmac100_tx_complete(priv);
1236 
1237 	/* Handle RX packets */
1238 	do {
1239 		more = ftgmac100_rx_packet(priv, &work_done);
1240 	} while (more && work_done < budget);
1241 
1242 
1243 	/* The interrupt is telling us to kick the MAC back to life
1244 	 * after an RX overflow
1245 	 */
1246 	if (unlikely(priv->need_mac_restart)) {
1247 		ftgmac100_start_hw(priv);
1248 		priv->need_mac_restart = false;
1249 
1250 		/* Re-enable "bad" interrupts */
1251 		iowrite32(FTGMAC100_INT_BAD,
1252 			  priv->base + FTGMAC100_OFFSET_IER);
1253 	}
1254 
1255 	/* As long as we are waiting for transmit packets to be
1256 	 * completed we keep NAPI going
1257 	 */
1258 	if (ftgmac100_tx_buf_cleanable(priv))
1259 		work_done = budget;
1260 
1261 	if (work_done < budget) {
1262 		/* We are about to re-enable all interrupts. However
1263 		 * the HW has been latching RX/TX packet interrupts while
1264 		 * they were masked. So we clear them first, then we need
1265 		 * to re-check if there's something to process
1266 		 */
1267 		iowrite32(FTGMAC100_INT_RXTX,
1268 			  priv->base + FTGMAC100_OFFSET_ISR);
1269 
1270 		/* Push the above (and provides a barrier vs. subsequent
1271 		 * reads of the descriptor).
1272 		 */
1273 		ioread32(priv->base + FTGMAC100_OFFSET_ISR);
1274 
1275 		/* Check RX and TX descriptors for more work to do */
1276 		if (ftgmac100_check_rx(priv) ||
1277 		    ftgmac100_tx_buf_cleanable(priv))
1278 			return budget;
1279 
1280 		/* deschedule NAPI */
1281 		napi_complete(napi);
1282 
1283 		/* enable all interrupts */
1284 		iowrite32(FTGMAC100_INT_ALL,
1285 			  priv->base + FTGMAC100_OFFSET_IER);
1286 	}
1287 
1288 	return work_done;
1289 }
1290 
1291 static int ftgmac100_init_all(struct ftgmac100 *priv, bool ignore_alloc_err)
1292 {
1293 	int err = 0;
1294 
1295 	/* Re-init descriptors (adjust queue sizes) */
1296 	ftgmac100_init_rings(priv);
1297 
1298 	/* Realloc rx descriptors */
1299 	err = ftgmac100_alloc_rx_buffers(priv);
1300 	if (err && !ignore_alloc_err)
1301 		return err;
1302 
1303 	/* Reinit and restart HW */
1304 	ftgmac100_init_hw(priv);
1305 	ftgmac100_config_pause(priv);
1306 	ftgmac100_start_hw(priv);
1307 
1308 	/* Re-enable the device */
1309 	napi_enable(&priv->napi);
1310 	netif_start_queue(priv->netdev);
1311 
1312 	/* Enable all interrupts */
1313 	iowrite32(FTGMAC100_INT_ALL, priv->base + FTGMAC100_OFFSET_IER);
1314 
1315 	return err;
1316 }
1317 
1318 static void ftgmac100_reset(struct ftgmac100 *priv)
1319 {
1320 	struct net_device *netdev = priv->netdev;
1321 	int err;
1322 
1323 	netdev_dbg(netdev, "Resetting NIC...\n");
1324 
1325 	/* Lock the world */
1326 	rtnl_lock();
1327 	if (netdev->phydev)
1328 		mutex_lock(&netdev->phydev->lock);
1329 	if (priv->mii_bus)
1330 		mutex_lock(&priv->mii_bus->mdio_lock);
1331 
1332 
1333 	/* Check if the interface is still up */
1334 	if (!netif_running(netdev))
1335 		goto bail;
1336 
1337 	/* Stop the network stack */
1338 	netif_trans_update(netdev);
1339 	napi_disable(&priv->napi);
1340 	netif_tx_disable(netdev);
1341 
1342 	/* Stop and reset the MAC */
1343 	ftgmac100_stop_hw(priv);
1344 	err = ftgmac100_reset_and_config_mac(priv);
1345 	if (err) {
1346 		/* Not much we can do ... it might come back... */
1347 		netdev_err(netdev, "attempting to continue...\n");
1348 	}
1349 
1350 	/* Free all rx and tx buffers */
1351 	ftgmac100_free_buffers(priv);
1352 
1353 	/* Setup everything again and restart chip */
1354 	ftgmac100_init_all(priv, true);
1355 
1356 	netdev_dbg(netdev, "Reset done !\n");
1357 bail:
1358 	if (priv->mii_bus)
1359 		mutex_unlock(&priv->mii_bus->mdio_lock);
1360 	if (netdev->phydev)
1361 		mutex_unlock(&netdev->phydev->lock);
1362 	rtnl_unlock();
1363 }
1364 
1365 static void ftgmac100_reset_task(struct work_struct *work)
1366 {
1367 	struct ftgmac100 *priv = container_of(work, struct ftgmac100,
1368 					      reset_task);
1369 
1370 	ftgmac100_reset(priv);
1371 }
1372 
1373 static void ftgmac100_adjust_link(struct net_device *netdev)
1374 {
1375 	struct ftgmac100 *priv = netdev_priv(netdev);
1376 	struct phy_device *phydev = netdev->phydev;
1377 	bool tx_pause, rx_pause;
1378 	int new_speed;
1379 
1380 	/* We store "no link" as speed 0 */
1381 	if (!phydev->link)
1382 		new_speed = 0;
1383 	else
1384 		new_speed = phydev->speed;
1385 
1386 	/* Grab pause settings from PHY if configured to do so */
1387 	if (priv->aneg_pause) {
1388 		rx_pause = tx_pause = phydev->pause;
1389 		if (phydev->asym_pause)
1390 			tx_pause = !rx_pause;
1391 	} else {
1392 		rx_pause = priv->rx_pause;
1393 		tx_pause = priv->tx_pause;
1394 	}
1395 
1396 	/* Link hasn't changed, do nothing */
1397 	if (phydev->speed == priv->cur_speed &&
1398 	    phydev->duplex == priv->cur_duplex &&
1399 	    rx_pause == priv->rx_pause &&
1400 	    tx_pause == priv->tx_pause)
1401 		return;
1402 
1403 	/* Print status if we have a link or we had one and just lost it,
1404 	 * don't print otherwise.
1405 	 */
1406 	if (new_speed || priv->cur_speed)
1407 		phy_print_status(phydev);
1408 
1409 	priv->cur_speed = new_speed;
1410 	priv->cur_duplex = phydev->duplex;
1411 	priv->rx_pause = rx_pause;
1412 	priv->tx_pause = tx_pause;
1413 
1414 	/* Link is down, do nothing else */
1415 	if (!new_speed)
1416 		return;
1417 
1418 	/* Disable all interrupts */
1419 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1420 
1421 	/* Release phy lock to allow ftgmac100_reset to aquire it, keeping lock
1422 	 * order consistent to prevent dead lock.
1423 	 */
1424 	if (netdev->phydev)
1425 		mutex_unlock(&netdev->phydev->lock);
1426 
1427 	ftgmac100_reset(priv);
1428 
1429 	if (netdev->phydev)
1430 		mutex_lock(&netdev->phydev->lock);
1431 
1432 }
1433 
1434 static int ftgmac100_mii_probe(struct net_device *netdev)
1435 {
1436 	struct ftgmac100 *priv = netdev_priv(netdev);
1437 	struct platform_device *pdev = to_platform_device(priv->dev);
1438 	struct device_node *np = pdev->dev.of_node;
1439 	struct phy_device *phydev;
1440 	phy_interface_t phy_intf;
1441 	int err;
1442 
1443 	/* Default to RGMII. It's a gigabit part after all */
1444 	err = of_get_phy_mode(np, &phy_intf);
1445 	if (err)
1446 		phy_intf = PHY_INTERFACE_MODE_RGMII;
1447 
1448 	/* Aspeed only supports these. I don't know about other IP
1449 	 * block vendors so I'm going to just let them through for
1450 	 * now. Note that this is only a warning if for some obscure
1451 	 * reason the DT really means to lie about it or it's a newer
1452 	 * part we don't know about.
1453 	 *
1454 	 * On the Aspeed SoC there are additionally straps and SCU
1455 	 * control bits that could tell us what the interface is
1456 	 * (or allow us to configure it while the IP block is held
1457 	 * in reset). For now I chose to keep this driver away from
1458 	 * those SoC specific bits and assume the device-tree is
1459 	 * right and the SCU has been configured properly by pinmux
1460 	 * or the firmware.
1461 	 */
1462 	if (priv->is_aspeed && !(phy_interface_mode_is_rgmii(phy_intf))) {
1463 		netdev_warn(netdev,
1464 			    "Unsupported PHY mode %s !\n",
1465 			    phy_modes(phy_intf));
1466 	}
1467 
1468 	phydev = phy_find_first(priv->mii_bus);
1469 	if (!phydev) {
1470 		netdev_info(netdev, "%s: no PHY found\n", netdev->name);
1471 		return -ENODEV;
1472 	}
1473 
1474 	phydev = phy_connect(netdev, phydev_name(phydev),
1475 			     &ftgmac100_adjust_link, phy_intf);
1476 
1477 	if (IS_ERR(phydev)) {
1478 		netdev_err(netdev, "%s: Could not attach to PHY\n", netdev->name);
1479 		return PTR_ERR(phydev);
1480 	}
1481 
1482 	/* Indicate that we support PAUSE frames (see comment in
1483 	 * Documentation/networking/phy.rst)
1484 	 */
1485 	phy_support_asym_pause(phydev);
1486 
1487 	/* Display what we found */
1488 	phy_attached_info(phydev);
1489 
1490 	return 0;
1491 }
1492 
1493 static int ftgmac100_open(struct net_device *netdev)
1494 {
1495 	struct ftgmac100 *priv = netdev_priv(netdev);
1496 	int err;
1497 
1498 	/* Allocate ring buffers  */
1499 	err = ftgmac100_alloc_rings(priv);
1500 	if (err) {
1501 		netdev_err(netdev, "Failed to allocate descriptors\n");
1502 		return err;
1503 	}
1504 
1505 	/* When using NC-SI we force the speed to 100Mbit/s full duplex,
1506 	 *
1507 	 * Otherwise we leave it set to 0 (no link), the link
1508 	 * message from the PHY layer will handle setting it up to
1509 	 * something else if needed.
1510 	 */
1511 	if (priv->use_ncsi) {
1512 		priv->cur_duplex = DUPLEX_FULL;
1513 		priv->cur_speed = SPEED_100;
1514 	} else {
1515 		priv->cur_duplex = 0;
1516 		priv->cur_speed = 0;
1517 	}
1518 
1519 	/* Reset the hardware */
1520 	err = ftgmac100_reset_and_config_mac(priv);
1521 	if (err)
1522 		goto err_hw;
1523 
1524 	/* Initialize NAPI */
1525 	netif_napi_add(netdev, &priv->napi, ftgmac100_poll);
1526 
1527 	/* Grab our interrupt */
1528 	err = request_irq(netdev->irq, ftgmac100_interrupt, 0, netdev->name, netdev);
1529 	if (err) {
1530 		netdev_err(netdev, "failed to request irq %d\n", netdev->irq);
1531 		goto err_irq;
1532 	}
1533 
1534 	/* Start things up */
1535 	err = ftgmac100_init_all(priv, false);
1536 	if (err) {
1537 		netdev_err(netdev, "Failed to allocate packet buffers\n");
1538 		goto err_alloc;
1539 	}
1540 
1541 	if (netdev->phydev) {
1542 		/* If we have a PHY, start polling */
1543 		phy_start(netdev->phydev);
1544 	} else if (priv->use_ncsi) {
1545 		/* If using NC-SI, set our carrier on and start the stack */
1546 		netif_carrier_on(netdev);
1547 
1548 		/* Start the NCSI device */
1549 		err = ncsi_start_dev(priv->ndev);
1550 		if (err)
1551 			goto err_ncsi;
1552 	}
1553 
1554 	return 0;
1555 
1556 err_ncsi:
1557 	napi_disable(&priv->napi);
1558 	netif_stop_queue(netdev);
1559 err_alloc:
1560 	ftgmac100_free_buffers(priv);
1561 	free_irq(netdev->irq, netdev);
1562 err_irq:
1563 	netif_napi_del(&priv->napi);
1564 err_hw:
1565 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1566 	ftgmac100_free_rings(priv);
1567 	return err;
1568 }
1569 
1570 static int ftgmac100_stop(struct net_device *netdev)
1571 {
1572 	struct ftgmac100 *priv = netdev_priv(netdev);
1573 
1574 	/* Note about the reset task: We are called with the rtnl lock
1575 	 * held, so we are synchronized against the core of the reset
1576 	 * task. We must not try to synchronously cancel it otherwise
1577 	 * we can deadlock. But since it will test for netif_running()
1578 	 * which has already been cleared by the net core, we don't
1579 	 * anything special to do.
1580 	 */
1581 
1582 	/* disable all interrupts */
1583 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1584 
1585 	netif_stop_queue(netdev);
1586 	napi_disable(&priv->napi);
1587 	netif_napi_del(&priv->napi);
1588 	if (netdev->phydev)
1589 		phy_stop(netdev->phydev);
1590 	else if (priv->use_ncsi)
1591 		ncsi_stop_dev(priv->ndev);
1592 
1593 	ftgmac100_stop_hw(priv);
1594 	free_irq(netdev->irq, netdev);
1595 	ftgmac100_free_buffers(priv);
1596 	ftgmac100_free_rings(priv);
1597 
1598 	return 0;
1599 }
1600 
1601 static void ftgmac100_tx_timeout(struct net_device *netdev, unsigned int txqueue)
1602 {
1603 	struct ftgmac100 *priv = netdev_priv(netdev);
1604 
1605 	/* Disable all interrupts */
1606 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1607 
1608 	/* Do the reset outside of interrupt context */
1609 	schedule_work(&priv->reset_task);
1610 }
1611 
1612 static int ftgmac100_set_features(struct net_device *netdev,
1613 				  netdev_features_t features)
1614 {
1615 	struct ftgmac100 *priv = netdev_priv(netdev);
1616 	netdev_features_t changed = netdev->features ^ features;
1617 
1618 	if (!netif_running(netdev))
1619 		return 0;
1620 
1621 	/* Update the vlan filtering bit */
1622 	if (changed & NETIF_F_HW_VLAN_CTAG_RX) {
1623 		u32 maccr;
1624 
1625 		maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
1626 		if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
1627 			maccr |= FTGMAC100_MACCR_RM_VLAN;
1628 		else
1629 			maccr &= ~FTGMAC100_MACCR_RM_VLAN;
1630 		iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
1631 	}
1632 
1633 	return 0;
1634 }
1635 
1636 #ifdef CONFIG_NET_POLL_CONTROLLER
1637 static void ftgmac100_poll_controller(struct net_device *netdev)
1638 {
1639 	unsigned long flags;
1640 
1641 	local_irq_save(flags);
1642 	ftgmac100_interrupt(netdev->irq, netdev);
1643 	local_irq_restore(flags);
1644 }
1645 #endif
1646 
1647 static const struct net_device_ops ftgmac100_netdev_ops = {
1648 	.ndo_open		= ftgmac100_open,
1649 	.ndo_stop		= ftgmac100_stop,
1650 	.ndo_start_xmit		= ftgmac100_hard_start_xmit,
1651 	.ndo_set_mac_address	= ftgmac100_set_mac_addr,
1652 	.ndo_validate_addr	= eth_validate_addr,
1653 	.ndo_eth_ioctl		= phy_do_ioctl,
1654 	.ndo_tx_timeout		= ftgmac100_tx_timeout,
1655 	.ndo_set_rx_mode	= ftgmac100_set_rx_mode,
1656 	.ndo_set_features	= ftgmac100_set_features,
1657 #ifdef CONFIG_NET_POLL_CONTROLLER
1658 	.ndo_poll_controller	= ftgmac100_poll_controller,
1659 #endif
1660 	.ndo_vlan_rx_add_vid	= ncsi_vlan_rx_add_vid,
1661 	.ndo_vlan_rx_kill_vid	= ncsi_vlan_rx_kill_vid,
1662 };
1663 
1664 static int ftgmac100_setup_mdio(struct net_device *netdev)
1665 {
1666 	struct ftgmac100 *priv = netdev_priv(netdev);
1667 	struct platform_device *pdev = to_platform_device(priv->dev);
1668 	struct device_node *np = pdev->dev.of_node;
1669 	struct device_node *mdio_np;
1670 	int i, err = 0;
1671 	u32 reg;
1672 
1673 	/* initialize mdio bus */
1674 	priv->mii_bus = mdiobus_alloc();
1675 	if (!priv->mii_bus)
1676 		return -EIO;
1677 
1678 	if (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
1679 	    of_device_is_compatible(np, "aspeed,ast2500-mac")) {
1680 		/* The AST2600 has a separate MDIO controller */
1681 
1682 		/* For the AST2400 and AST2500 this driver only supports the
1683 		 * old MDIO interface
1684 		 */
1685 		reg = ioread32(priv->base + FTGMAC100_OFFSET_REVR);
1686 		reg &= ~FTGMAC100_REVR_NEW_MDIO_INTERFACE;
1687 		iowrite32(reg, priv->base + FTGMAC100_OFFSET_REVR);
1688 	}
1689 
1690 	priv->mii_bus->name = "ftgmac100_mdio";
1691 	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%d",
1692 		 pdev->name, pdev->id);
1693 	priv->mii_bus->parent = priv->dev;
1694 	priv->mii_bus->priv = priv->netdev;
1695 	priv->mii_bus->read = ftgmac100_mdiobus_read;
1696 	priv->mii_bus->write = ftgmac100_mdiobus_write;
1697 
1698 	for (i = 0; i < PHY_MAX_ADDR; i++)
1699 		priv->mii_bus->irq[i] = PHY_POLL;
1700 
1701 	mdio_np = of_get_child_by_name(np, "mdio");
1702 
1703 	err = of_mdiobus_register(priv->mii_bus, mdio_np);
1704 	if (err) {
1705 		dev_err(priv->dev, "Cannot register MDIO bus!\n");
1706 		goto err_register_mdiobus;
1707 	}
1708 
1709 	of_node_put(mdio_np);
1710 
1711 	return 0;
1712 
1713 err_register_mdiobus:
1714 	mdiobus_free(priv->mii_bus);
1715 	return err;
1716 }
1717 
1718 static void ftgmac100_phy_disconnect(struct net_device *netdev)
1719 {
1720 	struct ftgmac100 *priv = netdev_priv(netdev);
1721 
1722 	if (!netdev->phydev)
1723 		return;
1724 
1725 	phy_disconnect(netdev->phydev);
1726 	if (of_phy_is_fixed_link(priv->dev->of_node))
1727 		of_phy_deregister_fixed_link(priv->dev->of_node);
1728 }
1729 
1730 static void ftgmac100_destroy_mdio(struct net_device *netdev)
1731 {
1732 	struct ftgmac100 *priv = netdev_priv(netdev);
1733 
1734 	if (!priv->mii_bus)
1735 		return;
1736 
1737 	mdiobus_unregister(priv->mii_bus);
1738 	mdiobus_free(priv->mii_bus);
1739 }
1740 
1741 static void ftgmac100_ncsi_handler(struct ncsi_dev *nd)
1742 {
1743 	if (unlikely(nd->state != ncsi_dev_state_functional))
1744 		return;
1745 
1746 	netdev_dbg(nd->dev, "NCSI interface %s\n",
1747 		   nd->link_up ? "up" : "down");
1748 }
1749 
1750 static int ftgmac100_setup_clk(struct ftgmac100 *priv)
1751 {
1752 	struct clk *clk;
1753 	int rc;
1754 
1755 	clk = devm_clk_get(priv->dev, NULL /* MACCLK */);
1756 	if (IS_ERR(clk))
1757 		return PTR_ERR(clk);
1758 	priv->clk = clk;
1759 	rc = clk_prepare_enable(priv->clk);
1760 	if (rc)
1761 		return rc;
1762 
1763 	/* Aspeed specifies a 100MHz clock is required for up to
1764 	 * 1000Mbit link speeds. As NCSI is limited to 100Mbit, 25MHz
1765 	 * is sufficient
1766 	 */
1767 	rc = clk_set_rate(priv->clk, priv->use_ncsi ? FTGMAC_25MHZ :
1768 			  FTGMAC_100MHZ);
1769 	if (rc)
1770 		goto cleanup_clk;
1771 
1772 	/* RCLK is for RMII, typically used for NCSI. Optional because it's not
1773 	 * necessary if it's the AST2400 MAC, or the MAC is configured for
1774 	 * RGMII, or the controller is not an ASPEED-based controller.
1775 	 */
1776 	priv->rclk = devm_clk_get_optional(priv->dev, "RCLK");
1777 	rc = clk_prepare_enable(priv->rclk);
1778 	if (!rc)
1779 		return 0;
1780 
1781 cleanup_clk:
1782 	clk_disable_unprepare(priv->clk);
1783 
1784 	return rc;
1785 }
1786 
1787 static bool ftgmac100_has_child_node(struct device_node *np, const char *name)
1788 {
1789 	struct device_node *child_np = of_get_child_by_name(np, name);
1790 	bool ret = false;
1791 
1792 	if (child_np) {
1793 		ret = true;
1794 		of_node_put(child_np);
1795 	}
1796 
1797 	return ret;
1798 }
1799 
1800 static int ftgmac100_probe(struct platform_device *pdev)
1801 {
1802 	struct resource *res;
1803 	int irq;
1804 	struct net_device *netdev;
1805 	struct ftgmac100 *priv;
1806 	struct device_node *np;
1807 	int err = 0;
1808 
1809 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1810 	if (!res)
1811 		return -ENXIO;
1812 
1813 	irq = platform_get_irq(pdev, 0);
1814 	if (irq < 0)
1815 		return irq;
1816 
1817 	/* setup net_device */
1818 	netdev = alloc_etherdev(sizeof(*priv));
1819 	if (!netdev) {
1820 		err = -ENOMEM;
1821 		goto err_alloc_etherdev;
1822 	}
1823 
1824 	SET_NETDEV_DEV(netdev, &pdev->dev);
1825 
1826 	netdev->ethtool_ops = &ftgmac100_ethtool_ops;
1827 	netdev->netdev_ops = &ftgmac100_netdev_ops;
1828 	netdev->watchdog_timeo = 5 * HZ;
1829 
1830 	platform_set_drvdata(pdev, netdev);
1831 
1832 	/* setup private data */
1833 	priv = netdev_priv(netdev);
1834 	priv->netdev = netdev;
1835 	priv->dev = &pdev->dev;
1836 	INIT_WORK(&priv->reset_task, ftgmac100_reset_task);
1837 
1838 	/* map io memory */
1839 	priv->res = request_mem_region(res->start, resource_size(res),
1840 				       dev_name(&pdev->dev));
1841 	if (!priv->res) {
1842 		dev_err(&pdev->dev, "Could not reserve memory region\n");
1843 		err = -ENOMEM;
1844 		goto err_req_mem;
1845 	}
1846 
1847 	priv->base = ioremap(res->start, resource_size(res));
1848 	if (!priv->base) {
1849 		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1850 		err = -EIO;
1851 		goto err_ioremap;
1852 	}
1853 
1854 	netdev->irq = irq;
1855 
1856 	/* Enable pause */
1857 	priv->tx_pause = true;
1858 	priv->rx_pause = true;
1859 	priv->aneg_pause = true;
1860 
1861 	/* MAC address from chip or random one */
1862 	err = ftgmac100_initial_mac(priv);
1863 	if (err)
1864 		goto err_phy_connect;
1865 
1866 	np = pdev->dev.of_node;
1867 	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
1868 		   of_device_is_compatible(np, "aspeed,ast2500-mac") ||
1869 		   of_device_is_compatible(np, "aspeed,ast2600-mac"))) {
1870 		priv->rxdes0_edorr_mask = BIT(30);
1871 		priv->txdes0_edotr_mask = BIT(30);
1872 		priv->is_aspeed = true;
1873 	} else {
1874 		priv->rxdes0_edorr_mask = BIT(15);
1875 		priv->txdes0_edotr_mask = BIT(15);
1876 	}
1877 
1878 	if (np && of_get_property(np, "use-ncsi", NULL)) {
1879 		if (!IS_ENABLED(CONFIG_NET_NCSI)) {
1880 			dev_err(&pdev->dev, "NCSI stack not enabled\n");
1881 			err = -EINVAL;
1882 			goto err_phy_connect;
1883 		}
1884 
1885 		dev_info(&pdev->dev, "Using NCSI interface\n");
1886 		priv->use_ncsi = true;
1887 		priv->ndev = ncsi_register_dev(netdev, ftgmac100_ncsi_handler);
1888 		if (!priv->ndev) {
1889 			err = -EINVAL;
1890 			goto err_phy_connect;
1891 		}
1892 	} else if (np && of_phy_is_fixed_link(np)) {
1893 		struct phy_device *phy;
1894 
1895 		err = of_phy_register_fixed_link(np);
1896 		if (err) {
1897 			dev_err(&pdev->dev, "Failed to register fixed PHY\n");
1898 			goto err_phy_connect;
1899 		}
1900 
1901 		phy = of_phy_get_and_connect(priv->netdev, np,
1902 					     &ftgmac100_adjust_link);
1903 		if (!phy) {
1904 			dev_err(&pdev->dev, "Failed to connect to fixed PHY\n");
1905 			of_phy_deregister_fixed_link(np);
1906 			err = -EINVAL;
1907 			goto err_phy_connect;
1908 		}
1909 
1910 		/* Display what we found */
1911 		phy_attached_info(phy);
1912 	} else if (np && of_get_property(np, "phy-handle", NULL)) {
1913 		struct phy_device *phy;
1914 
1915 		/* Support "mdio"/"phy" child nodes for ast2400/2500 with
1916 		 * an embedded MDIO controller. Automatically scan the DTS for
1917 		 * available PHYs and register them.
1918 		 */
1919 		if (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
1920 		    of_device_is_compatible(np, "aspeed,ast2500-mac")) {
1921 			err = ftgmac100_setup_mdio(netdev);
1922 			if (err)
1923 				goto err_setup_mdio;
1924 		}
1925 
1926 		phy = of_phy_get_and_connect(priv->netdev, np,
1927 					     &ftgmac100_adjust_link);
1928 		if (!phy) {
1929 			dev_err(&pdev->dev, "Failed to connect to phy\n");
1930 			err = -EINVAL;
1931 			goto err_phy_connect;
1932 		}
1933 
1934 		/* Indicate that we support PAUSE frames (see comment in
1935 		 * Documentation/networking/phy.rst)
1936 		 */
1937 		phy_support_asym_pause(phy);
1938 
1939 		/* Display what we found */
1940 		phy_attached_info(phy);
1941 	} else if (np && !ftgmac100_has_child_node(np, "mdio")) {
1942 		/* Support legacy ASPEED devicetree descriptions that decribe a
1943 		 * MAC with an embedded MDIO controller but have no "mdio"
1944 		 * child node. Automatically scan the MDIO bus for available
1945 		 * PHYs.
1946 		 */
1947 		priv->use_ncsi = false;
1948 		err = ftgmac100_setup_mdio(netdev);
1949 		if (err)
1950 			goto err_setup_mdio;
1951 
1952 		err = ftgmac100_mii_probe(netdev);
1953 		if (err) {
1954 			dev_err(priv->dev, "MII probe failed!\n");
1955 			goto err_ncsi_dev;
1956 		}
1957 
1958 	}
1959 
1960 	if (priv->is_aspeed) {
1961 		err = ftgmac100_setup_clk(priv);
1962 		if (err)
1963 			goto err_phy_connect;
1964 
1965 		/* Disable ast2600 problematic HW arbitration */
1966 		if (of_device_is_compatible(np, "aspeed,ast2600-mac"))
1967 			iowrite32(FTGMAC100_TM_DEFAULT,
1968 				  priv->base + FTGMAC100_OFFSET_TM);
1969 	}
1970 
1971 	/* Default ring sizes */
1972 	priv->rx_q_entries = priv->new_rx_q_entries = DEF_RX_QUEUE_ENTRIES;
1973 	priv->tx_q_entries = priv->new_tx_q_entries = DEF_TX_QUEUE_ENTRIES;
1974 
1975 	/* Base feature set */
1976 	netdev->hw_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM |
1977 		NETIF_F_GRO | NETIF_F_SG | NETIF_F_HW_VLAN_CTAG_RX |
1978 		NETIF_F_HW_VLAN_CTAG_TX;
1979 
1980 	if (priv->use_ncsi)
1981 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1982 
1983 	/* AST2400  doesn't have working HW checksum generation */
1984 	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac")))
1985 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
1986 
1987 	/* AST2600 tx checksum with NCSI is broken */
1988 	if (priv->use_ncsi && of_device_is_compatible(np, "aspeed,ast2600-mac"))
1989 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
1990 
1991 	if (np && of_get_property(np, "no-hw-checksum", NULL))
1992 		netdev->hw_features &= ~(NETIF_F_HW_CSUM | NETIF_F_RXCSUM);
1993 	netdev->features |= netdev->hw_features;
1994 
1995 	/* register network device */
1996 	err = register_netdev(netdev);
1997 	if (err) {
1998 		dev_err(&pdev->dev, "Failed to register netdev\n");
1999 		goto err_register_netdev;
2000 	}
2001 
2002 	netdev_info(netdev, "irq %d, mapped at %p\n", netdev->irq, priv->base);
2003 
2004 	return 0;
2005 
2006 err_register_netdev:
2007 	clk_disable_unprepare(priv->rclk);
2008 	clk_disable_unprepare(priv->clk);
2009 err_phy_connect:
2010 	ftgmac100_phy_disconnect(netdev);
2011 err_ncsi_dev:
2012 	if (priv->ndev)
2013 		ncsi_unregister_dev(priv->ndev);
2014 	ftgmac100_destroy_mdio(netdev);
2015 err_setup_mdio:
2016 	iounmap(priv->base);
2017 err_ioremap:
2018 	release_resource(priv->res);
2019 err_req_mem:
2020 	free_netdev(netdev);
2021 err_alloc_etherdev:
2022 	return err;
2023 }
2024 
2025 static int ftgmac100_remove(struct platform_device *pdev)
2026 {
2027 	struct net_device *netdev;
2028 	struct ftgmac100 *priv;
2029 
2030 	netdev = platform_get_drvdata(pdev);
2031 	priv = netdev_priv(netdev);
2032 
2033 	if (priv->ndev)
2034 		ncsi_unregister_dev(priv->ndev);
2035 	unregister_netdev(netdev);
2036 
2037 	clk_disable_unprepare(priv->rclk);
2038 	clk_disable_unprepare(priv->clk);
2039 
2040 	/* There's a small chance the reset task will have been re-queued,
2041 	 * during stop, make sure it's gone before we free the structure.
2042 	 */
2043 	cancel_work_sync(&priv->reset_task);
2044 
2045 	ftgmac100_phy_disconnect(netdev);
2046 	ftgmac100_destroy_mdio(netdev);
2047 
2048 	iounmap(priv->base);
2049 	release_resource(priv->res);
2050 
2051 	netif_napi_del(&priv->napi);
2052 	free_netdev(netdev);
2053 	return 0;
2054 }
2055 
2056 static const struct of_device_id ftgmac100_of_match[] = {
2057 	{ .compatible = "faraday,ftgmac100" },
2058 	{ }
2059 };
2060 MODULE_DEVICE_TABLE(of, ftgmac100_of_match);
2061 
2062 static struct platform_driver ftgmac100_driver = {
2063 	.probe	= ftgmac100_probe,
2064 	.remove	= ftgmac100_remove,
2065 	.driver	= {
2066 		.name		= DRV_NAME,
2067 		.of_match_table	= ftgmac100_of_match,
2068 	},
2069 };
2070 module_platform_driver(ftgmac100_driver);
2071 
2072 MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
2073 MODULE_DESCRIPTION("FTGMAC100 driver");
2074 MODULE_LICENSE("GPL");
2075