xref: /linux/drivers/net/ethernet/faraday/ftgmac100.c (revision 7ac5dddef5168b13e490402802f7628d012f477d)
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/reset.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/etherdevice.h>
15 #include <linux/ethtool.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/module.h>
19 #include <linux/netdevice.h>
20 #include <linux/of.h>
21 #include <linux/of_mdio.h>
22 #include <linux/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/property.h>
25 #include <linux/crc32.h>
26 #include <linux/if_vlan.h>
27 #include <linux/of_net.h>
28 #include <linux/phy_fixed.h>
29 #include <net/ip.h>
30 #include <net/ncsi.h>
31 
32 #include "ftgmac100.h"
33 
34 #define DRV_NAME	"ftgmac100"
35 
36 enum ftgmac100_mac_id {
37 	FTGMAC100_FARADAY = 1,
38 	FTGMAC100_AST2400,
39 	FTGMAC100_AST2500,
40 	FTGMAC100_AST2600
41 };
42 
43 struct ftgmac100_match_data {
44 	enum ftgmac100_mac_id mac_id;
45 };
46 
47 /* Arbitrary values, I am not sure the HW has limits */
48 #define MAX_RX_QUEUE_ENTRIES	1024
49 #define MAX_TX_QUEUE_ENTRIES	1024
50 #define MIN_RX_QUEUE_ENTRIES	32
51 #define MIN_TX_QUEUE_ENTRIES	32
52 
53 /* Defaults */
54 #define DEF_RX_QUEUE_ENTRIES	128
55 #define DEF_TX_QUEUE_ENTRIES	128
56 
57 #define MAX_PKT_SIZE		1536
58 #define RX_BUF_SIZE		MAX_PKT_SIZE	/* must be smaller than 0x3fff */
59 
60 /* Min number of tx ring entries before stopping queue */
61 #define TX_THRESHOLD		(MAX_SKB_FRAGS + 1)
62 
63 #define FTGMAC_100MHZ		100000000
64 #define FTGMAC_25MHZ		25000000
65 
66 /* For NC-SI to register a fixed-link phy device */
67 static struct fixed_phy_status ncsi_phy_status = {
68 	.link = 1,
69 	.speed = SPEED_100,
70 	.duplex = DUPLEX_FULL,
71 	.pause = 0,
72 	.asym_pause = 0
73 };
74 
75 struct ftgmac100 {
76 	/* Registers */
77 	struct resource *res;
78 	void __iomem *base;
79 
80 	enum ftgmac100_mac_id mac_id;
81 
82 	/* Rx ring */
83 	unsigned int rx_q_entries;
84 	struct ftgmac100_rxdes *rxdes;
85 	dma_addr_t rxdes_dma;
86 	struct sk_buff **rx_skbs;
87 	unsigned int rx_pointer;
88 	u32 rxdes0_edorr_mask;
89 
90 	/* Tx ring */
91 	unsigned int tx_q_entries;
92 	struct ftgmac100_txdes *txdes;
93 	dma_addr_t txdes_dma;
94 	struct sk_buff **tx_skbs;
95 	unsigned int tx_clean_pointer;
96 	unsigned int tx_pointer;
97 	u32 txdes0_edotr_mask;
98 
99 	/* Used to signal the reset task of ring change request */
100 	unsigned int new_rx_q_entries;
101 	unsigned int new_tx_q_entries;
102 
103 	/* Scratch page to use when rx skb alloc fails */
104 	void *rx_scratch;
105 	dma_addr_t rx_scratch_dma;
106 
107 	/* Component structures */
108 	struct net_device *netdev;
109 	struct device *dev;
110 	struct ncsi_dev *ndev;
111 	struct napi_struct napi;
112 	struct work_struct reset_task;
113 	struct mii_bus *mii_bus;
114 	struct clk *clk;
115 
116 	/* AST2500/AST2600 RMII ref clock gate */
117 	struct clk *rclk;
118 	/* Aspeed reset control */
119 	struct reset_control *rst;
120 
121 	/* Link management */
122 	int cur_speed;
123 	int cur_duplex;
124 	bool use_ncsi;
125 
126 	/* Multicast filter settings */
127 	u32 maht0;
128 	u32 maht1;
129 
130 	/* Flow control settings */
131 	bool tx_pause;
132 	bool rx_pause;
133 	bool aneg_pause;
134 
135 	/* Misc */
136 	bool need_mac_restart;
137 	bool is_aspeed;
138 };
139 
140 static int ftgmac100_reset_mac(struct ftgmac100 *priv, u32 maccr)
141 {
142 	struct net_device *netdev = priv->netdev;
143 	int i;
144 
145 	/* NOTE: reset clears all registers */
146 	iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
147 	iowrite32(maccr | FTGMAC100_MACCR_SW_RST,
148 		  priv->base + FTGMAC100_OFFSET_MACCR);
149 	for (i = 0; i < 200; i++) {
150 		unsigned int maccr;
151 
152 		maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
153 		if (!(maccr & FTGMAC100_MACCR_SW_RST))
154 			return 0;
155 
156 		udelay(1);
157 	}
158 
159 	netdev_err(netdev, "Hardware reset failed\n");
160 	return -EIO;
161 }
162 
163 static int ftgmac100_reset_and_config_mac(struct ftgmac100 *priv)
164 {
165 	u32 maccr = 0;
166 
167 	/* Aspeed RMII needs SCU reset to clear status */
168 	if (priv->is_aspeed && priv->netdev->phydev->interface == PHY_INTERFACE_MODE_RMII) {
169 		int err;
170 
171 		err = reset_control_assert(priv->rst);
172 		if (err) {
173 			dev_err(priv->dev, "Failed to reset mac (%d)\n", err);
174 			return err;
175 		}
176 		usleep_range(10000, 20000);
177 		err = reset_control_deassert(priv->rst);
178 		if (err) {
179 			dev_err(priv->dev, "Failed to deassert mac reset (%d)\n", err);
180 			return err;
181 		}
182 	}
183 
184 	switch (priv->cur_speed) {
185 	case SPEED_10:
186 	case 0: /* no link */
187 		break;
188 
189 	case SPEED_100:
190 		maccr |= FTGMAC100_MACCR_FAST_MODE;
191 		break;
192 
193 	case SPEED_1000:
194 		maccr |= FTGMAC100_MACCR_GIGA_MODE;
195 		break;
196 	default:
197 		netdev_err(priv->netdev, "Unknown speed %d !\n",
198 			   priv->cur_speed);
199 		break;
200 	}
201 
202 	/* (Re)initialize the queue pointers */
203 	priv->rx_pointer = 0;
204 	priv->tx_clean_pointer = 0;
205 	priv->tx_pointer = 0;
206 
207 	/* The doc says reset twice with 10us interval */
208 	if (ftgmac100_reset_mac(priv, maccr))
209 		return -EIO;
210 	usleep_range(10, 1000);
211 	return ftgmac100_reset_mac(priv, maccr);
212 }
213 
214 static void ftgmac100_write_mac_addr(struct ftgmac100 *priv, const u8 *mac)
215 {
216 	unsigned int maddr = mac[0] << 8 | mac[1];
217 	unsigned int laddr = mac[2] << 24 | mac[3] << 16 | mac[4] << 8 | mac[5];
218 
219 	iowrite32(maddr, priv->base + FTGMAC100_OFFSET_MAC_MADR);
220 	iowrite32(laddr, priv->base + FTGMAC100_OFFSET_MAC_LADR);
221 }
222 
223 static int ftgmac100_initial_mac(struct ftgmac100 *priv)
224 {
225 	u8 mac[ETH_ALEN];
226 	unsigned int m;
227 	unsigned int l;
228 	int err;
229 
230 	err = of_get_ethdev_address(priv->dev->of_node, priv->netdev);
231 	if (err == -EPROBE_DEFER)
232 		return err;
233 	if (!err) {
234 		dev_info(priv->dev, "Read MAC address %pM from device tree\n",
235 			 priv->netdev->dev_addr);
236 		return 0;
237 	}
238 
239 	m = ioread32(priv->base + FTGMAC100_OFFSET_MAC_MADR);
240 	l = ioread32(priv->base + FTGMAC100_OFFSET_MAC_LADR);
241 
242 	mac[0] = (m >> 8) & 0xff;
243 	mac[1] = m & 0xff;
244 	mac[2] = (l >> 24) & 0xff;
245 	mac[3] = (l >> 16) & 0xff;
246 	mac[4] = (l >> 8) & 0xff;
247 	mac[5] = l & 0xff;
248 
249 	if (is_valid_ether_addr(mac)) {
250 		eth_hw_addr_set(priv->netdev, mac);
251 		dev_info(priv->dev, "Read MAC address %pM from chip\n", mac);
252 	} else {
253 		eth_hw_addr_random(priv->netdev);
254 		dev_info(priv->dev, "Generated random MAC address %pM\n",
255 			 priv->netdev->dev_addr);
256 	}
257 
258 	return 0;
259 }
260 
261 static int ftgmac100_set_mac_addr(struct net_device *dev, void *p)
262 {
263 	int ret;
264 
265 	ret = eth_prepare_mac_addr_change(dev, p);
266 	if (ret < 0)
267 		return ret;
268 
269 	eth_commit_mac_addr_change(dev, p);
270 	ftgmac100_write_mac_addr(netdev_priv(dev), dev->dev_addr);
271 
272 	return 0;
273 }
274 
275 static void ftgmac100_config_pause(struct ftgmac100 *priv)
276 {
277 	u32 fcr = FTGMAC100_FCR_PAUSE_TIME(16);
278 
279 	/* Throttle tx queue when receiving pause frames */
280 	if (priv->rx_pause)
281 		fcr |= FTGMAC100_FCR_FC_EN;
282 
283 	/* Enables sending pause frames when the RX queue is past a
284 	 * certain threshold.
285 	 */
286 	if (priv->tx_pause)
287 		fcr |= FTGMAC100_FCR_FCTHR_EN;
288 
289 	iowrite32(fcr, priv->base + FTGMAC100_OFFSET_FCR);
290 }
291 
292 static void ftgmac100_init_hw(struct ftgmac100 *priv)
293 {
294 	u32 reg, rfifo_sz, tfifo_sz;
295 
296 	/* Clear stale interrupts */
297 	reg = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
298 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_ISR);
299 
300 	/* Setup RX ring buffer base */
301 	iowrite32(priv->rxdes_dma, priv->base + FTGMAC100_OFFSET_RXR_BADR);
302 
303 	/* Setup TX ring buffer base */
304 	iowrite32(priv->txdes_dma, priv->base + FTGMAC100_OFFSET_NPTXR_BADR);
305 
306 	/* Configure RX buffer size */
307 	iowrite32(FTGMAC100_RBSR_SIZE(RX_BUF_SIZE),
308 		  priv->base + FTGMAC100_OFFSET_RBSR);
309 
310 	/* Set RX descriptor autopoll */
311 	iowrite32(FTGMAC100_APTC_RXPOLL_CNT(1),
312 		  priv->base + FTGMAC100_OFFSET_APTC);
313 
314 	/* Write MAC address */
315 	ftgmac100_write_mac_addr(priv, priv->netdev->dev_addr);
316 
317 	/* Write multicast filter */
318 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
319 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
320 
321 	/* Configure descriptor sizes and increase burst sizes according
322 	 * to values in Aspeed SDK. The FIFO arbitration is enabled and
323 	 * the thresholds set based on the recommended values in the
324 	 * AST2400 specification.
325 	 */
326 	iowrite32(FTGMAC100_DBLAC_RXDES_SIZE(2) |   /* 2*8 bytes RX descs */
327 		  FTGMAC100_DBLAC_TXDES_SIZE(2) |   /* 2*8 bytes TX descs */
328 		  FTGMAC100_DBLAC_RXBURST_SIZE(3) | /* 512 bytes max RX bursts */
329 		  FTGMAC100_DBLAC_TXBURST_SIZE(3) | /* 512 bytes max TX bursts */
330 		  FTGMAC100_DBLAC_RX_THR_EN |       /* Enable fifo threshold arb */
331 		  FTGMAC100_DBLAC_RXFIFO_HTHR(6) |  /* 6/8 of FIFO high threshold */
332 		  FTGMAC100_DBLAC_RXFIFO_LTHR(2),   /* 2/8 of FIFO low threshold */
333 		  priv->base + FTGMAC100_OFFSET_DBLAC);
334 
335 	/* Interrupt mitigation configured for 1 interrupt/packet. HW interrupt
336 	 * mitigation doesn't seem to provide any benefit with NAPI so leave
337 	 * it at that.
338 	 */
339 	iowrite32(FTGMAC100_ITC_RXINT_THR(1) |
340 		  FTGMAC100_ITC_TXINT_THR(1),
341 		  priv->base + FTGMAC100_OFFSET_ITC);
342 
343 	/* Configure FIFO sizes in the TPAFCR register */
344 	reg = ioread32(priv->base + FTGMAC100_OFFSET_FEAR);
345 	rfifo_sz = reg & 0x00000007;
346 	tfifo_sz = (reg >> 3) & 0x00000007;
347 	reg = ioread32(priv->base + FTGMAC100_OFFSET_TPAFCR);
348 	reg &= ~0x3f000000;
349 	reg |= (tfifo_sz << 27);
350 	reg |= (rfifo_sz << 24);
351 	iowrite32(reg, priv->base + FTGMAC100_OFFSET_TPAFCR);
352 }
353 
354 static void ftgmac100_start_hw(struct ftgmac100 *priv)
355 {
356 	u32 maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
357 
358 	/* Keep the original GMAC and FAST bits */
359 	maccr &= (FTGMAC100_MACCR_FAST_MODE | FTGMAC100_MACCR_GIGA_MODE);
360 
361 	/* Add all the main enable bits */
362 	maccr |= FTGMAC100_MACCR_TXDMA_EN	|
363 		 FTGMAC100_MACCR_RXDMA_EN	|
364 		 FTGMAC100_MACCR_TXMAC_EN	|
365 		 FTGMAC100_MACCR_RXMAC_EN	|
366 		 FTGMAC100_MACCR_CRC_APD	|
367 		 FTGMAC100_MACCR_PHY_LINK_LEVEL	|
368 		 FTGMAC100_MACCR_RX_RUNT	|
369 		 FTGMAC100_MACCR_RX_BROADPKT;
370 
371 	/* Add other bits as needed */
372 	if (priv->cur_duplex == DUPLEX_FULL)
373 		maccr |= FTGMAC100_MACCR_FULLDUP;
374 	if (priv->netdev->flags & IFF_PROMISC)
375 		maccr |= FTGMAC100_MACCR_RX_ALL;
376 	if (priv->netdev->flags & IFF_ALLMULTI)
377 		maccr |= FTGMAC100_MACCR_RX_MULTIPKT;
378 	else if (netdev_mc_count(priv->netdev))
379 		maccr |= FTGMAC100_MACCR_HT_MULTI_EN;
380 
381 	/* Vlan filtering enabled */
382 	if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
383 		maccr |= FTGMAC100_MACCR_RM_VLAN;
384 
385 	/* Hit the HW */
386 	iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
387 }
388 
389 static void ftgmac100_stop_hw(struct ftgmac100 *priv)
390 {
391 	iowrite32(0, priv->base + FTGMAC100_OFFSET_MACCR);
392 }
393 
394 static void ftgmac100_calc_mc_hash(struct ftgmac100 *priv)
395 {
396 	struct netdev_hw_addr *ha;
397 
398 	priv->maht1 = 0;
399 	priv->maht0 = 0;
400 	netdev_for_each_mc_addr(ha, priv->netdev) {
401 		u32 crc_val = ether_crc_le(ETH_ALEN, ha->addr);
402 
403 		crc_val = (~(crc_val >> 2)) & 0x3f;
404 		if (crc_val >= 32)
405 			priv->maht1 |= 1ul << (crc_val - 32);
406 		else
407 			priv->maht0 |= 1ul << (crc_val);
408 	}
409 }
410 
411 static void ftgmac100_set_rx_mode(struct net_device *netdev)
412 {
413 	struct ftgmac100 *priv = netdev_priv(netdev);
414 
415 	/* Setup the hash filter */
416 	ftgmac100_calc_mc_hash(priv);
417 
418 	/* Interface down ? that's all there is to do */
419 	if (!netif_running(netdev))
420 		return;
421 
422 	/* Update the HW */
423 	iowrite32(priv->maht0, priv->base + FTGMAC100_OFFSET_MAHT0);
424 	iowrite32(priv->maht1, priv->base + FTGMAC100_OFFSET_MAHT1);
425 
426 	/* Reconfigure MACCR */
427 	ftgmac100_start_hw(priv);
428 }
429 
430 static int ftgmac100_alloc_rx_buf(struct ftgmac100 *priv, unsigned int entry,
431 				  struct ftgmac100_rxdes *rxdes, gfp_t gfp)
432 {
433 	struct net_device *netdev = priv->netdev;
434 	struct sk_buff *skb;
435 	dma_addr_t map;
436 	int err = 0;
437 
438 	skb = netdev_alloc_skb_ip_align(netdev, RX_BUF_SIZE);
439 	if (unlikely(!skb)) {
440 		if (net_ratelimit())
441 			netdev_warn(netdev, "failed to allocate rx skb\n");
442 		err = -ENOMEM;
443 		map = priv->rx_scratch_dma;
444 	} else {
445 		map = dma_map_single(priv->dev, skb->data, RX_BUF_SIZE,
446 				     DMA_FROM_DEVICE);
447 		if (unlikely(dma_mapping_error(priv->dev, map))) {
448 			if (net_ratelimit())
449 				netdev_err(netdev, "failed to map rx page\n");
450 			dev_kfree_skb_any(skb);
451 			map = priv->rx_scratch_dma;
452 			skb = NULL;
453 			err = -ENOMEM;
454 		}
455 	}
456 
457 	/* Store skb */
458 	priv->rx_skbs[entry] = skb;
459 
460 	/* Store DMA address into RX desc */
461 	rxdes->rxdes3 = cpu_to_le32(map);
462 
463 	/* Ensure the above is ordered vs clearing the OWN bit */
464 	dma_wmb();
465 
466 	/* Clean status (which resets own bit) */
467 	if (entry == (priv->rx_q_entries - 1))
468 		rxdes->rxdes0 = cpu_to_le32(priv->rxdes0_edorr_mask);
469 	else
470 		rxdes->rxdes0 = 0;
471 
472 	return err;
473 }
474 
475 static unsigned int ftgmac100_next_rx_pointer(struct ftgmac100 *priv,
476 					      unsigned int pointer)
477 {
478 	return (pointer + 1) & (priv->rx_q_entries - 1);
479 }
480 
481 static void ftgmac100_rx_packet_error(struct ftgmac100 *priv, u32 status)
482 {
483 	struct net_device *netdev = priv->netdev;
484 
485 	if (status & FTGMAC100_RXDES0_RX_ERR)
486 		netdev->stats.rx_errors++;
487 
488 	if (status & FTGMAC100_RXDES0_CRC_ERR)
489 		netdev->stats.rx_crc_errors++;
490 
491 	if (status & (FTGMAC100_RXDES0_FTL |
492 		      FTGMAC100_RXDES0_RUNT |
493 		      FTGMAC100_RXDES0_RX_ODD_NB))
494 		netdev->stats.rx_length_errors++;
495 }
496 
497 static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed)
498 {
499 	struct net_device *netdev = priv->netdev;
500 	struct ftgmac100_rxdes *rxdes;
501 	struct sk_buff *skb;
502 	unsigned int pointer, size;
503 	u32 status, csum_vlan;
504 	dma_addr_t map;
505 
506 	/* Grab next RX descriptor */
507 	pointer = priv->rx_pointer;
508 	rxdes = &priv->rxdes[pointer];
509 
510 	/* Grab descriptor status */
511 	status = le32_to_cpu(rxdes->rxdes0);
512 
513 	/* Do we have a packet ? */
514 	if (!(status & FTGMAC100_RXDES0_RXPKT_RDY))
515 		return false;
516 
517 	/* Order subsequent reads with the test for the ready bit */
518 	dma_rmb();
519 
520 	/* We don't cope with fragmented RX packets */
521 	if (unlikely(!(status & FTGMAC100_RXDES0_FRS) ||
522 		     !(status & FTGMAC100_RXDES0_LRS)))
523 		goto drop;
524 
525 	/* Grab received size and csum vlan field in the descriptor */
526 	size = status & FTGMAC100_RXDES0_VDBC;
527 	csum_vlan = le32_to_cpu(rxdes->rxdes1);
528 
529 	/* Any error (other than csum offload) flagged ? */
530 	if (unlikely(status & RXDES0_ANY_ERROR)) {
531 		/* Correct for incorrect flagging of runt packets
532 		 * with vlan tags... Just accept a runt packet that
533 		 * has been flagged as vlan and whose size is at
534 		 * least 60 bytes.
535 		 */
536 		if ((status & FTGMAC100_RXDES0_RUNT) &&
537 		    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL) &&
538 		    (size >= 60))
539 			status &= ~FTGMAC100_RXDES0_RUNT;
540 
541 		/* Any error still in there ? */
542 		if (status & RXDES0_ANY_ERROR) {
543 			ftgmac100_rx_packet_error(priv, status);
544 			goto drop;
545 		}
546 	}
547 
548 	/* If the packet had no skb (failed to allocate earlier)
549 	 * then try to allocate one and skip
550 	 */
551 	skb = priv->rx_skbs[pointer];
552 	if (!unlikely(skb)) {
553 		ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
554 		goto drop;
555 	}
556 
557 	if (unlikely(status & FTGMAC100_RXDES0_MULTICAST))
558 		netdev->stats.multicast++;
559 
560 	/* If the HW found checksum errors, bounce it to software.
561 	 *
562 	 * If we didn't, we need to see if the packet was recognized
563 	 * by HW as one of the supported checksummed protocols before
564 	 * we accept the HW test results.
565 	 */
566 	if (netdev->features & NETIF_F_RXCSUM) {
567 		u32 err_bits = FTGMAC100_RXDES1_TCP_CHKSUM_ERR |
568 			FTGMAC100_RXDES1_UDP_CHKSUM_ERR |
569 			FTGMAC100_RXDES1_IP_CHKSUM_ERR;
570 		if ((csum_vlan & err_bits) ||
571 		    !(csum_vlan & FTGMAC100_RXDES1_PROT_MASK))
572 			skb->ip_summed = CHECKSUM_NONE;
573 		else
574 			skb->ip_summed = CHECKSUM_UNNECESSARY;
575 	}
576 
577 	/* Transfer received size to skb */
578 	skb_put(skb, size);
579 
580 	/* Extract vlan tag */
581 	if ((netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
582 	    (csum_vlan & FTGMAC100_RXDES1_VLANTAG_AVAIL))
583 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
584 				       csum_vlan & 0xffff);
585 
586 	/* Tear down DMA mapping, do necessary cache management */
587 	map = le32_to_cpu(rxdes->rxdes3);
588 
589 #if defined(CONFIG_ARM) && !defined(CONFIG_ARM_DMA_USE_IOMMU)
590 	/* When we don't have an iommu, we can save cycles by not
591 	 * invalidating the cache for the part of the packet that
592 	 * wasn't received.
593 	 */
594 	dma_unmap_single(priv->dev, map, size, DMA_FROM_DEVICE);
595 #else
596 	dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
597 #endif
598 
599 
600 	/* Resplenish rx ring */
601 	ftgmac100_alloc_rx_buf(priv, pointer, rxdes, GFP_ATOMIC);
602 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
603 
604 	skb->protocol = eth_type_trans(skb, netdev);
605 
606 	netdev->stats.rx_packets++;
607 	netdev->stats.rx_bytes += size;
608 
609 	/* push packet to protocol stack */
610 	if (skb->ip_summed == CHECKSUM_NONE)
611 		netif_receive_skb(skb);
612 	else
613 		napi_gro_receive(&priv->napi, skb);
614 
615 	(*processed)++;
616 	return true;
617 
618 drop:
619 	/* Clean rxdes0 (which resets own bit) */
620 	rxdes->rxdes0 = cpu_to_le32(status & priv->rxdes0_edorr_mask);
621 	priv->rx_pointer = ftgmac100_next_rx_pointer(priv, pointer);
622 	netdev->stats.rx_dropped++;
623 	return true;
624 }
625 
626 static u32 ftgmac100_base_tx_ctlstat(struct ftgmac100 *priv,
627 				     unsigned int index)
628 {
629 	if (index == (priv->tx_q_entries - 1))
630 		return priv->txdes0_edotr_mask;
631 	else
632 		return 0;
633 }
634 
635 static unsigned int ftgmac100_next_tx_pointer(struct ftgmac100 *priv,
636 					      unsigned int pointer)
637 {
638 	return (pointer + 1) & (priv->tx_q_entries - 1);
639 }
640 
641 static u32 ftgmac100_tx_buf_avail(struct ftgmac100 *priv)
642 {
643 	/* Returns the number of available slots in the TX queue
644 	 *
645 	 * This always leaves one free slot so we don't have to
646 	 * worry about empty vs. full, and this simplifies the
647 	 * test for ftgmac100_tx_buf_cleanable() below
648 	 */
649 	return (priv->tx_clean_pointer - priv->tx_pointer - 1) &
650 		(priv->tx_q_entries - 1);
651 }
652 
653 static bool ftgmac100_tx_buf_cleanable(struct ftgmac100 *priv)
654 {
655 	return priv->tx_pointer != priv->tx_clean_pointer;
656 }
657 
658 static void ftgmac100_free_tx_packet(struct ftgmac100 *priv,
659 				     unsigned int pointer,
660 				     struct sk_buff *skb,
661 				     struct ftgmac100_txdes *txdes,
662 				     u32 ctl_stat)
663 {
664 	dma_addr_t map = le32_to_cpu(txdes->txdes3);
665 	size_t len;
666 
667 	if (ctl_stat & FTGMAC100_TXDES0_FTS) {
668 		len = skb_headlen(skb);
669 		dma_unmap_single(priv->dev, map, len, DMA_TO_DEVICE);
670 	} else {
671 		len = FTGMAC100_TXDES0_TXBUF_SIZE(ctl_stat);
672 		dma_unmap_page(priv->dev, map, len, DMA_TO_DEVICE);
673 	}
674 
675 	/* Free SKB on last segment */
676 	if (ctl_stat & FTGMAC100_TXDES0_LTS)
677 		dev_kfree_skb(skb);
678 	priv->tx_skbs[pointer] = NULL;
679 }
680 
681 static bool ftgmac100_tx_complete_packet(struct ftgmac100 *priv)
682 {
683 	struct net_device *netdev = priv->netdev;
684 	struct ftgmac100_txdes *txdes;
685 	struct sk_buff *skb;
686 	unsigned int pointer;
687 	u32 ctl_stat;
688 
689 	pointer = priv->tx_clean_pointer;
690 	txdes = &priv->txdes[pointer];
691 
692 	ctl_stat = le32_to_cpu(txdes->txdes0);
693 	if (ctl_stat & FTGMAC100_TXDES0_TXDMA_OWN)
694 		return false;
695 
696 	skb = priv->tx_skbs[pointer];
697 	netdev->stats.tx_packets++;
698 	netdev->stats.tx_bytes += skb->len;
699 	ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
700 	txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
701 
702 	/* Ensure the descriptor config is visible before setting the tx
703 	 * pointer.
704 	 */
705 	smp_wmb();
706 
707 	priv->tx_clean_pointer = ftgmac100_next_tx_pointer(priv, pointer);
708 
709 	return true;
710 }
711 
712 static void ftgmac100_tx_complete(struct ftgmac100 *priv)
713 {
714 	struct net_device *netdev = priv->netdev;
715 
716 	/* Process all completed packets */
717 	while (ftgmac100_tx_buf_cleanable(priv) &&
718 	       ftgmac100_tx_complete_packet(priv))
719 		;
720 
721 	/* Restart queue if needed */
722 	smp_mb();
723 	if (unlikely(netif_queue_stopped(netdev) &&
724 		     ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)) {
725 		struct netdev_queue *txq;
726 
727 		txq = netdev_get_tx_queue(netdev, 0);
728 		__netif_tx_lock(txq, smp_processor_id());
729 		if (netif_queue_stopped(netdev) &&
730 		    ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
731 			netif_wake_queue(netdev);
732 		__netif_tx_unlock(txq);
733 	}
734 }
735 
736 static bool ftgmac100_prep_tx_csum(struct sk_buff *skb, u32 *csum_vlan)
737 {
738 	if (skb->protocol == cpu_to_be16(ETH_P_IP)) {
739 		u8 ip_proto = ip_hdr(skb)->protocol;
740 
741 		*csum_vlan |= FTGMAC100_TXDES1_IP_CHKSUM;
742 		switch(ip_proto) {
743 		case IPPROTO_TCP:
744 			*csum_vlan |= FTGMAC100_TXDES1_TCP_CHKSUM;
745 			return true;
746 		case IPPROTO_UDP:
747 			*csum_vlan |= FTGMAC100_TXDES1_UDP_CHKSUM;
748 			return true;
749 		case IPPROTO_IP:
750 			return true;
751 		}
752 	}
753 	return skb_checksum_help(skb) == 0;
754 }
755 
756 static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb,
757 					     struct net_device *netdev)
758 {
759 	struct ftgmac100 *priv = netdev_priv(netdev);
760 	struct ftgmac100_txdes *txdes, *first;
761 	unsigned int pointer, nfrags, len, i, j;
762 	u32 f_ctl_stat, ctl_stat, csum_vlan;
763 	dma_addr_t map;
764 
765 	/* The HW doesn't pad small frames */
766 	if (eth_skb_pad(skb)) {
767 		netdev->stats.tx_dropped++;
768 		return NETDEV_TX_OK;
769 	}
770 
771 	/* Reject oversize packets */
772 	if (unlikely(skb->len > MAX_PKT_SIZE)) {
773 		if (net_ratelimit())
774 			netdev_dbg(netdev, "tx packet too big\n");
775 		goto drop;
776 	}
777 
778 	/* Do we have a limit on #fragments ? I yet have to get a reply
779 	 * from Aspeed. If there's one I haven't hit it.
780 	 */
781 	nfrags = skb_shinfo(skb)->nr_frags;
782 
783 	/* Setup HW checksumming */
784 	csum_vlan = 0;
785 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
786 	    !ftgmac100_prep_tx_csum(skb, &csum_vlan))
787 		goto drop;
788 
789 	/* Add VLAN tag */
790 	if (skb_vlan_tag_present(skb)) {
791 		csum_vlan |= FTGMAC100_TXDES1_INS_VLANTAG;
792 		csum_vlan |= skb_vlan_tag_get(skb) & 0xffff;
793 	}
794 
795 	/* Get header len */
796 	len = skb_headlen(skb);
797 
798 	/* Map the packet head */
799 	map = dma_map_single(priv->dev, skb->data, len, DMA_TO_DEVICE);
800 	if (dma_mapping_error(priv->dev, map)) {
801 		if (net_ratelimit())
802 			netdev_err(netdev, "map tx packet head failed\n");
803 		goto drop;
804 	}
805 
806 	/* Grab the next free tx descriptor */
807 	pointer = priv->tx_pointer;
808 	txdes = first = &priv->txdes[pointer];
809 
810 	/* Setup it up with the packet head. Don't write the head to the
811 	 * ring just yet
812 	 */
813 	priv->tx_skbs[pointer] = skb;
814 	f_ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
815 	f_ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
816 	f_ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
817 	f_ctl_stat |= FTGMAC100_TXDES0_FTS;
818 	if (nfrags == 0)
819 		f_ctl_stat |= FTGMAC100_TXDES0_LTS;
820 	txdes->txdes3 = cpu_to_le32(map);
821 	txdes->txdes1 = cpu_to_le32(csum_vlan);
822 
823 	/* Next descriptor */
824 	pointer = ftgmac100_next_tx_pointer(priv, pointer);
825 
826 	/* Add the fragments */
827 	for (i = 0; i < nfrags; i++) {
828 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
829 
830 		len = skb_frag_size(frag);
831 
832 		/* Map it */
833 		map = skb_frag_dma_map(priv->dev, frag, 0, len,
834 				       DMA_TO_DEVICE);
835 		if (dma_mapping_error(priv->dev, map))
836 			goto dma_err;
837 
838 		/* Setup descriptor */
839 		priv->tx_skbs[pointer] = skb;
840 		txdes = &priv->txdes[pointer];
841 		ctl_stat = ftgmac100_base_tx_ctlstat(priv, pointer);
842 		ctl_stat |= FTGMAC100_TXDES0_TXDMA_OWN;
843 		ctl_stat |= FTGMAC100_TXDES0_TXBUF_SIZE(len);
844 		if (i == (nfrags - 1))
845 			ctl_stat |= FTGMAC100_TXDES0_LTS;
846 		txdes->txdes0 = cpu_to_le32(ctl_stat);
847 		txdes->txdes1 = 0;
848 		txdes->txdes3 = cpu_to_le32(map);
849 
850 		/* Next one */
851 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
852 	}
853 
854 	/* Order the previous packet and descriptor udpates
855 	 * before setting the OWN bit on the first descriptor.
856 	 */
857 	dma_wmb();
858 	first->txdes0 = cpu_to_le32(f_ctl_stat);
859 
860 	/* Ensure the descriptor config is visible before setting the tx
861 	 * pointer.
862 	 */
863 	smp_wmb();
864 
865 	/* Update next TX pointer */
866 	priv->tx_pointer = pointer;
867 
868 	/* If there isn't enough room for all the fragments of a new packet
869 	 * in the TX ring, stop the queue. The sequence below is race free
870 	 * vs. a concurrent restart in ftgmac100_poll()
871 	 */
872 	if (unlikely(ftgmac100_tx_buf_avail(priv) < TX_THRESHOLD)) {
873 		netif_stop_queue(netdev);
874 		/* Order the queue stop with the test below */
875 		smp_mb();
876 		if (ftgmac100_tx_buf_avail(priv) >= TX_THRESHOLD)
877 			netif_wake_queue(netdev);
878 	}
879 
880 	/* Poke transmitter to read the updated TX descriptors */
881 	iowrite32(1, priv->base + FTGMAC100_OFFSET_NPTXPD);
882 
883 	return NETDEV_TX_OK;
884 
885 dma_err:
886 	if (net_ratelimit())
887 		netdev_err(netdev, "map tx fragment failed\n");
888 
889 	/* Free head */
890 	pointer = priv->tx_pointer;
891 	ftgmac100_free_tx_packet(priv, pointer, skb, first, f_ctl_stat);
892 	first->txdes0 = cpu_to_le32(f_ctl_stat & priv->txdes0_edotr_mask);
893 
894 	/* Then all fragments */
895 	for (j = 0; j < i; j++) {
896 		pointer = ftgmac100_next_tx_pointer(priv, pointer);
897 		txdes = &priv->txdes[pointer];
898 		ctl_stat = le32_to_cpu(txdes->txdes0);
899 		ftgmac100_free_tx_packet(priv, pointer, skb, txdes, ctl_stat);
900 		txdes->txdes0 = cpu_to_le32(ctl_stat & priv->txdes0_edotr_mask);
901 	}
902 
903 	/* This cannot be reached if we successfully mapped the
904 	 * last fragment, so we know ftgmac100_free_tx_packet()
905 	 * hasn't freed the skb yet.
906 	 */
907 drop:
908 	/* Drop the packet */
909 	dev_kfree_skb_any(skb);
910 	netdev->stats.tx_dropped++;
911 
912 	return NETDEV_TX_OK;
913 }
914 
915 static void ftgmac100_free_buffers(struct ftgmac100 *priv)
916 {
917 	int i;
918 
919 	/* Free all RX buffers */
920 	for (i = 0; i < priv->rx_q_entries; i++) {
921 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
922 		struct sk_buff *skb = priv->rx_skbs[i];
923 		dma_addr_t map = le32_to_cpu(rxdes->rxdes3);
924 
925 		if (!skb)
926 			continue;
927 
928 		priv->rx_skbs[i] = NULL;
929 		dma_unmap_single(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
930 		dev_kfree_skb_any(skb);
931 	}
932 
933 	/* Free all TX buffers */
934 	for (i = 0; i < priv->tx_q_entries; i++) {
935 		struct ftgmac100_txdes *txdes = &priv->txdes[i];
936 		struct sk_buff *skb = priv->tx_skbs[i];
937 
938 		if (!skb)
939 			continue;
940 		ftgmac100_free_tx_packet(priv, i, skb, txdes,
941 					 le32_to_cpu(txdes->txdes0));
942 	}
943 }
944 
945 static void ftgmac100_free_rings(struct ftgmac100 *priv)
946 {
947 	/* Free skb arrays */
948 	kfree(priv->rx_skbs);
949 	kfree(priv->tx_skbs);
950 
951 	/* Free descriptors */
952 	if (priv->rxdes)
953 		dma_free_coherent(priv->dev, MAX_RX_QUEUE_ENTRIES *
954 				  sizeof(struct ftgmac100_rxdes),
955 				  priv->rxdes, priv->rxdes_dma);
956 	priv->rxdes = NULL;
957 
958 	if (priv->txdes)
959 		dma_free_coherent(priv->dev, MAX_TX_QUEUE_ENTRIES *
960 				  sizeof(struct ftgmac100_txdes),
961 				  priv->txdes, priv->txdes_dma);
962 	priv->txdes = NULL;
963 
964 	/* Free scratch packet buffer */
965 	if (priv->rx_scratch)
966 		dma_free_coherent(priv->dev, RX_BUF_SIZE,
967 				  priv->rx_scratch, priv->rx_scratch_dma);
968 }
969 
970 static int ftgmac100_alloc_rings(struct ftgmac100 *priv)
971 {
972 	/* Allocate skb arrays */
973 	priv->rx_skbs = kcalloc(MAX_RX_QUEUE_ENTRIES, sizeof(void *),
974 				GFP_KERNEL);
975 	if (!priv->rx_skbs)
976 		return -ENOMEM;
977 	priv->tx_skbs = kcalloc(MAX_TX_QUEUE_ENTRIES, sizeof(void *),
978 				GFP_KERNEL);
979 	if (!priv->tx_skbs)
980 		return -ENOMEM;
981 
982 	/* Allocate descriptors */
983 	priv->rxdes = dma_alloc_coherent(priv->dev,
984 					 MAX_RX_QUEUE_ENTRIES * sizeof(struct ftgmac100_rxdes),
985 					 &priv->rxdes_dma, GFP_KERNEL);
986 	if (!priv->rxdes)
987 		return -ENOMEM;
988 	priv->txdes = dma_alloc_coherent(priv->dev,
989 					 MAX_TX_QUEUE_ENTRIES * sizeof(struct ftgmac100_txdes),
990 					 &priv->txdes_dma, GFP_KERNEL);
991 	if (!priv->txdes)
992 		return -ENOMEM;
993 
994 	/* Allocate scratch packet buffer */
995 	priv->rx_scratch = dma_alloc_coherent(priv->dev,
996 					      RX_BUF_SIZE,
997 					      &priv->rx_scratch_dma,
998 					      GFP_KERNEL);
999 	if (!priv->rx_scratch)
1000 		return -ENOMEM;
1001 
1002 	return 0;
1003 }
1004 
1005 static void ftgmac100_init_rings(struct ftgmac100 *priv)
1006 {
1007 	struct ftgmac100_rxdes *rxdes = NULL;
1008 	struct ftgmac100_txdes *txdes = NULL;
1009 	int i;
1010 
1011 	/* Update entries counts */
1012 	priv->rx_q_entries = priv->new_rx_q_entries;
1013 	priv->tx_q_entries = priv->new_tx_q_entries;
1014 
1015 	if (WARN_ON(priv->rx_q_entries < MIN_RX_QUEUE_ENTRIES))
1016 		return;
1017 
1018 	/* Initialize RX ring */
1019 	for (i = 0; i < priv->rx_q_entries; i++) {
1020 		rxdes = &priv->rxdes[i];
1021 		rxdes->rxdes0 = 0;
1022 		rxdes->rxdes3 = cpu_to_le32(priv->rx_scratch_dma);
1023 	}
1024 	/* Mark the end of the ring */
1025 	rxdes->rxdes0 |= cpu_to_le32(priv->rxdes0_edorr_mask);
1026 
1027 	if (WARN_ON(priv->tx_q_entries < MIN_RX_QUEUE_ENTRIES))
1028 		return;
1029 
1030 	/* Initialize TX ring */
1031 	for (i = 0; i < priv->tx_q_entries; i++) {
1032 		txdes = &priv->txdes[i];
1033 		txdes->txdes0 = 0;
1034 	}
1035 	txdes->txdes0 |= cpu_to_le32(priv->txdes0_edotr_mask);
1036 }
1037 
1038 static int ftgmac100_alloc_rx_buffers(struct ftgmac100 *priv)
1039 {
1040 	int i;
1041 
1042 	for (i = 0; i < priv->rx_q_entries; i++) {
1043 		struct ftgmac100_rxdes *rxdes = &priv->rxdes[i];
1044 
1045 		if (ftgmac100_alloc_rx_buf(priv, i, rxdes, GFP_KERNEL))
1046 			return -ENOMEM;
1047 	}
1048 	return 0;
1049 }
1050 
1051 static int ftgmac100_mdiobus_read(struct mii_bus *bus, int phy_addr, int regnum)
1052 {
1053 	struct net_device *netdev = bus->priv;
1054 	struct ftgmac100 *priv = netdev_priv(netdev);
1055 	unsigned int phycr;
1056 	int i;
1057 
1058 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1059 
1060 	/* preserve MDC cycle threshold */
1061 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1062 
1063 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1064 		 FTGMAC100_PHYCR_REGAD(regnum) |
1065 		 FTGMAC100_PHYCR_MIIRD;
1066 
1067 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1068 
1069 	for (i = 0; i < 10; i++) {
1070 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1071 
1072 		if ((phycr & FTGMAC100_PHYCR_MIIRD) == 0) {
1073 			int data;
1074 
1075 			data = ioread32(priv->base + FTGMAC100_OFFSET_PHYDATA);
1076 			return FTGMAC100_PHYDATA_MIIRDATA(data);
1077 		}
1078 
1079 		udelay(100);
1080 	}
1081 
1082 	netdev_err(netdev, "mdio read timed out\n");
1083 	return -EIO;
1084 }
1085 
1086 static int ftgmac100_mdiobus_write(struct mii_bus *bus, int phy_addr,
1087 				   int regnum, u16 value)
1088 {
1089 	struct net_device *netdev = bus->priv;
1090 	struct ftgmac100 *priv = netdev_priv(netdev);
1091 	unsigned int phycr;
1092 	int data;
1093 	int i;
1094 
1095 	phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1096 
1097 	/* preserve MDC cycle threshold */
1098 	phycr &= FTGMAC100_PHYCR_MDC_CYCTHR_MASK;
1099 
1100 	phycr |= FTGMAC100_PHYCR_PHYAD(phy_addr) |
1101 		 FTGMAC100_PHYCR_REGAD(regnum) |
1102 		 FTGMAC100_PHYCR_MIIWR;
1103 
1104 	data = FTGMAC100_PHYDATA_MIIWDATA(value);
1105 
1106 	iowrite32(data, priv->base + FTGMAC100_OFFSET_PHYDATA);
1107 	iowrite32(phycr, priv->base + FTGMAC100_OFFSET_PHYCR);
1108 
1109 	for (i = 0; i < 10; i++) {
1110 		phycr = ioread32(priv->base + FTGMAC100_OFFSET_PHYCR);
1111 
1112 		if ((phycr & FTGMAC100_PHYCR_MIIWR) == 0)
1113 			return 0;
1114 
1115 		udelay(100);
1116 	}
1117 
1118 	netdev_err(netdev, "mdio write timed out\n");
1119 	return -EIO;
1120 }
1121 
1122 static void ftgmac100_get_drvinfo(struct net_device *netdev,
1123 				  struct ethtool_drvinfo *info)
1124 {
1125 	strscpy(info->driver, DRV_NAME, sizeof(info->driver));
1126 	strscpy(info->bus_info, dev_name(&netdev->dev), sizeof(info->bus_info));
1127 }
1128 
1129 static void
1130 ftgmac100_get_ringparam(struct net_device *netdev,
1131 			struct ethtool_ringparam *ering,
1132 			struct kernel_ethtool_ringparam *kernel_ering,
1133 			struct netlink_ext_ack *extack)
1134 {
1135 	struct ftgmac100 *priv = netdev_priv(netdev);
1136 
1137 	memset(ering, 0, sizeof(*ering));
1138 	ering->rx_max_pending = MAX_RX_QUEUE_ENTRIES;
1139 	ering->tx_max_pending = MAX_TX_QUEUE_ENTRIES;
1140 	ering->rx_pending = priv->rx_q_entries;
1141 	ering->tx_pending = priv->tx_q_entries;
1142 }
1143 
1144 static int
1145 ftgmac100_set_ringparam(struct net_device *netdev,
1146 			struct ethtool_ringparam *ering,
1147 			struct kernel_ethtool_ringparam *kernel_ering,
1148 			struct netlink_ext_ack *extack)
1149 {
1150 	struct ftgmac100 *priv = netdev_priv(netdev);
1151 
1152 	if (ering->rx_pending > MAX_RX_QUEUE_ENTRIES ||
1153 	    ering->tx_pending > MAX_TX_QUEUE_ENTRIES ||
1154 	    ering->rx_pending < MIN_RX_QUEUE_ENTRIES ||
1155 	    ering->tx_pending < MIN_TX_QUEUE_ENTRIES ||
1156 	    !is_power_of_2(ering->rx_pending) ||
1157 	    !is_power_of_2(ering->tx_pending))
1158 		return -EINVAL;
1159 
1160 	priv->new_rx_q_entries = ering->rx_pending;
1161 	priv->new_tx_q_entries = ering->tx_pending;
1162 	if (netif_running(netdev))
1163 		schedule_work(&priv->reset_task);
1164 
1165 	return 0;
1166 }
1167 
1168 static void ftgmac100_get_pauseparam(struct net_device *netdev,
1169 				     struct ethtool_pauseparam *pause)
1170 {
1171 	struct ftgmac100 *priv = netdev_priv(netdev);
1172 
1173 	pause->autoneg = priv->aneg_pause;
1174 	pause->tx_pause = priv->tx_pause;
1175 	pause->rx_pause = priv->rx_pause;
1176 }
1177 
1178 static int ftgmac100_set_pauseparam(struct net_device *netdev,
1179 				    struct ethtool_pauseparam *pause)
1180 {
1181 	struct ftgmac100 *priv = netdev_priv(netdev);
1182 	struct phy_device *phydev = netdev->phydev;
1183 
1184 	priv->aneg_pause = pause->autoneg;
1185 	priv->tx_pause = pause->tx_pause;
1186 	priv->rx_pause = pause->rx_pause;
1187 
1188 	if (phydev)
1189 		phy_set_asym_pause(phydev, pause->rx_pause, pause->tx_pause);
1190 
1191 	if (netif_running(netdev)) {
1192 		if (!(phydev && priv->aneg_pause))
1193 			ftgmac100_config_pause(priv);
1194 	}
1195 
1196 	return 0;
1197 }
1198 
1199 static const struct ethtool_ops ftgmac100_ethtool_ops = {
1200 	.get_drvinfo		= ftgmac100_get_drvinfo,
1201 	.get_link		= ethtool_op_get_link,
1202 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1203 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1204 	.nway_reset		= phy_ethtool_nway_reset,
1205 	.get_ringparam		= ftgmac100_get_ringparam,
1206 	.set_ringparam		= ftgmac100_set_ringparam,
1207 	.get_pauseparam		= ftgmac100_get_pauseparam,
1208 	.set_pauseparam		= ftgmac100_set_pauseparam,
1209 };
1210 
1211 static irqreturn_t ftgmac100_interrupt(int irq, void *dev_id)
1212 {
1213 	struct net_device *netdev = dev_id;
1214 	struct ftgmac100 *priv = netdev_priv(netdev);
1215 	unsigned int status, new_mask = FTGMAC100_INT_BAD;
1216 
1217 	/* Fetch and clear interrupt bits, process abnormal ones */
1218 	status = ioread32(priv->base + FTGMAC100_OFFSET_ISR);
1219 	iowrite32(status, priv->base + FTGMAC100_OFFSET_ISR);
1220 	if (unlikely(status & FTGMAC100_INT_BAD)) {
1221 
1222 		/* RX buffer unavailable */
1223 		if (status & FTGMAC100_INT_NO_RXBUF)
1224 			netdev->stats.rx_over_errors++;
1225 
1226 		/* received packet lost due to RX FIFO full */
1227 		if (status & FTGMAC100_INT_RPKT_LOST)
1228 			netdev->stats.rx_fifo_errors++;
1229 
1230 		/* sent packet lost due to excessive TX collision */
1231 		if (status & FTGMAC100_INT_XPKT_LOST)
1232 			netdev->stats.tx_fifo_errors++;
1233 
1234 		/* AHB error -> Reset the chip */
1235 		if (status & FTGMAC100_INT_AHB_ERR) {
1236 			if (net_ratelimit())
1237 				netdev_warn(netdev,
1238 					   "AHB bus error ! Resetting chip.\n");
1239 			iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1240 			schedule_work(&priv->reset_task);
1241 			return IRQ_HANDLED;
1242 		}
1243 
1244 		/* We may need to restart the MAC after such errors, delay
1245 		 * this until after we have freed some Rx buffers though
1246 		 */
1247 		priv->need_mac_restart = true;
1248 
1249 		/* Disable those errors until we restart */
1250 		new_mask &= ~status;
1251 	}
1252 
1253 	/* Only enable "bad" interrupts while NAPI is on */
1254 	iowrite32(new_mask, priv->base + FTGMAC100_OFFSET_IER);
1255 
1256 	/* Schedule NAPI bh */
1257 	napi_schedule_irqoff(&priv->napi);
1258 
1259 	return IRQ_HANDLED;
1260 }
1261 
1262 static bool ftgmac100_check_rx(struct ftgmac100 *priv)
1263 {
1264 	struct ftgmac100_rxdes *rxdes = &priv->rxdes[priv->rx_pointer];
1265 
1266 	/* Do we have a packet ? */
1267 	return !!(rxdes->rxdes0 & cpu_to_le32(FTGMAC100_RXDES0_RXPKT_RDY));
1268 }
1269 
1270 static int ftgmac100_poll(struct napi_struct *napi, int budget)
1271 {
1272 	struct ftgmac100 *priv = container_of(napi, struct ftgmac100, napi);
1273 	int work_done = 0;
1274 	bool more;
1275 
1276 	/* Handle TX completions */
1277 	if (ftgmac100_tx_buf_cleanable(priv))
1278 		ftgmac100_tx_complete(priv);
1279 
1280 	/* Handle RX packets */
1281 	do {
1282 		more = ftgmac100_rx_packet(priv, &work_done);
1283 	} while (more && work_done < budget);
1284 
1285 
1286 	/* The interrupt is telling us to kick the MAC back to life
1287 	 * after an RX overflow
1288 	 */
1289 	if (unlikely(priv->need_mac_restart)) {
1290 		ftgmac100_start_hw(priv);
1291 		priv->need_mac_restart = false;
1292 
1293 		/* Re-enable "bad" interrupts */
1294 		iowrite32(FTGMAC100_INT_BAD,
1295 			  priv->base + FTGMAC100_OFFSET_IER);
1296 	}
1297 
1298 	/* As long as we are waiting for transmit packets to be
1299 	 * completed we keep NAPI going
1300 	 */
1301 	if (ftgmac100_tx_buf_cleanable(priv))
1302 		work_done = budget;
1303 
1304 	if (work_done < budget) {
1305 		/* We are about to re-enable all interrupts. However
1306 		 * the HW has been latching RX/TX packet interrupts while
1307 		 * they were masked. So we clear them first, then we need
1308 		 * to re-check if there's something to process
1309 		 */
1310 		iowrite32(FTGMAC100_INT_RXTX,
1311 			  priv->base + FTGMAC100_OFFSET_ISR);
1312 
1313 		/* Push the above (and provides a barrier vs. subsequent
1314 		 * reads of the descriptor).
1315 		 */
1316 		ioread32(priv->base + FTGMAC100_OFFSET_ISR);
1317 
1318 		/* Check RX and TX descriptors for more work to do */
1319 		if (ftgmac100_check_rx(priv) ||
1320 		    ftgmac100_tx_buf_cleanable(priv))
1321 			return budget;
1322 
1323 		/* deschedule NAPI */
1324 		napi_complete(napi);
1325 
1326 		/* enable all interrupts */
1327 		iowrite32(FTGMAC100_INT_ALL,
1328 			  priv->base + FTGMAC100_OFFSET_IER);
1329 	}
1330 
1331 	return work_done;
1332 }
1333 
1334 static int ftgmac100_init_all(struct ftgmac100 *priv, bool ignore_alloc_err)
1335 {
1336 	int err = 0;
1337 
1338 	/* Re-init descriptors (adjust queue sizes) */
1339 	ftgmac100_init_rings(priv);
1340 
1341 	/* Realloc rx descriptors */
1342 	err = ftgmac100_alloc_rx_buffers(priv);
1343 	if (err && !ignore_alloc_err)
1344 		return err;
1345 
1346 	/* Reinit and restart HW */
1347 	ftgmac100_init_hw(priv);
1348 	ftgmac100_config_pause(priv);
1349 	ftgmac100_start_hw(priv);
1350 
1351 	/* Re-enable the device */
1352 	napi_enable(&priv->napi);
1353 	netif_start_queue(priv->netdev);
1354 
1355 	/* Enable all interrupts */
1356 	iowrite32(FTGMAC100_INT_ALL, priv->base + FTGMAC100_OFFSET_IER);
1357 
1358 	return err;
1359 }
1360 
1361 static void ftgmac100_reset(struct ftgmac100 *priv)
1362 {
1363 	struct net_device *netdev = priv->netdev;
1364 	int err;
1365 
1366 	netdev_dbg(netdev, "Resetting NIC...\n");
1367 
1368 	/* Lock the world */
1369 	rtnl_lock();
1370 	if (netdev->phydev)
1371 		mutex_lock(&netdev->phydev->lock);
1372 	if (priv->mii_bus)
1373 		mutex_lock(&priv->mii_bus->mdio_lock);
1374 
1375 
1376 	/* Check if the interface is still up */
1377 	if (!netif_running(netdev))
1378 		goto bail;
1379 
1380 	/* Stop the network stack */
1381 	netif_trans_update(netdev);
1382 	napi_disable(&priv->napi);
1383 	netif_tx_disable(netdev);
1384 
1385 	/* Stop and reset the MAC */
1386 	ftgmac100_stop_hw(priv);
1387 	err = ftgmac100_reset_and_config_mac(priv);
1388 	if (err) {
1389 		/* Not much we can do ... it might come back... */
1390 		netdev_err(netdev, "attempting to continue...\n");
1391 	}
1392 
1393 	/* Free all rx and tx buffers */
1394 	ftgmac100_free_buffers(priv);
1395 
1396 	/* Setup everything again and restart chip */
1397 	ftgmac100_init_all(priv, true);
1398 
1399 	netdev_dbg(netdev, "Reset done !\n");
1400 bail:
1401 	if (priv->mii_bus)
1402 		mutex_unlock(&priv->mii_bus->mdio_lock);
1403 	if (netdev->phydev)
1404 		mutex_unlock(&netdev->phydev->lock);
1405 	rtnl_unlock();
1406 }
1407 
1408 static void ftgmac100_reset_task(struct work_struct *work)
1409 {
1410 	struct ftgmac100 *priv = container_of(work, struct ftgmac100,
1411 					      reset_task);
1412 
1413 	ftgmac100_reset(priv);
1414 }
1415 
1416 static void ftgmac100_adjust_link(struct net_device *netdev)
1417 {
1418 	struct ftgmac100 *priv = netdev_priv(netdev);
1419 	struct phy_device *phydev = netdev->phydev;
1420 	bool tx_pause, rx_pause;
1421 	int new_speed;
1422 
1423 	/* We store "no link" as speed 0 */
1424 	if (!phydev->link)
1425 		new_speed = 0;
1426 	else
1427 		new_speed = phydev->speed;
1428 
1429 	/* Grab pause settings from PHY if configured to do so */
1430 	if (priv->aneg_pause) {
1431 		rx_pause = tx_pause = phydev->pause;
1432 		if (phydev->asym_pause)
1433 			tx_pause = !rx_pause;
1434 	} else {
1435 		rx_pause = priv->rx_pause;
1436 		tx_pause = priv->tx_pause;
1437 	}
1438 
1439 	/* Link hasn't changed, do nothing */
1440 	if (phydev->speed == priv->cur_speed &&
1441 	    phydev->duplex == priv->cur_duplex &&
1442 	    rx_pause == priv->rx_pause &&
1443 	    tx_pause == priv->tx_pause)
1444 		return;
1445 
1446 	/* Print status if we have a link or we had one and just lost it,
1447 	 * don't print otherwise.
1448 	 */
1449 	if (new_speed || priv->cur_speed)
1450 		phy_print_status(phydev);
1451 
1452 	priv->cur_speed = new_speed;
1453 	priv->cur_duplex = phydev->duplex;
1454 	priv->rx_pause = rx_pause;
1455 	priv->tx_pause = tx_pause;
1456 
1457 	/* Link is down, do nothing else */
1458 	if (!new_speed)
1459 		return;
1460 
1461 	/* Disable all interrupts */
1462 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1463 
1464 	/* Release phy lock to allow ftgmac100_reset to acquire it, keeping lock
1465 	 * order consistent to prevent dead lock.
1466 	 */
1467 	if (netdev->phydev)
1468 		mutex_unlock(&netdev->phydev->lock);
1469 
1470 	ftgmac100_reset(priv);
1471 
1472 	if (netdev->phydev)
1473 		mutex_lock(&netdev->phydev->lock);
1474 
1475 }
1476 
1477 static int ftgmac100_mii_probe(struct net_device *netdev)
1478 {
1479 	struct ftgmac100 *priv = netdev_priv(netdev);
1480 	struct platform_device *pdev = to_platform_device(priv->dev);
1481 	struct device_node *np = pdev->dev.of_node;
1482 	struct phy_device *phydev;
1483 	phy_interface_t phy_intf;
1484 	int err;
1485 
1486 	if (!priv->mii_bus) {
1487 		dev_err(priv->dev, "No MDIO bus available\n");
1488 		return -ENODEV;
1489 	}
1490 
1491 	/* Default to RGMII. It's a gigabit part after all */
1492 	err = of_get_phy_mode(np, &phy_intf);
1493 	if (err)
1494 		phy_intf = PHY_INTERFACE_MODE_RGMII;
1495 
1496 	/* Aspeed only supports these. I don't know about other IP
1497 	 * block vendors so I'm going to just let them through for
1498 	 * now. Note that this is only a warning if for some obscure
1499 	 * reason the DT really means to lie about it or it's a newer
1500 	 * part we don't know about.
1501 	 *
1502 	 * On the Aspeed SoC there are additionally straps and SCU
1503 	 * control bits that could tell us what the interface is
1504 	 * (or allow us to configure it while the IP block is held
1505 	 * in reset). For now I chose to keep this driver away from
1506 	 * those SoC specific bits and assume the device-tree is
1507 	 * right and the SCU has been configured properly by pinmux
1508 	 * or the firmware.
1509 	 */
1510 	if (priv->is_aspeed && !(phy_interface_mode_is_rgmii(phy_intf))) {
1511 		netdev_warn(netdev,
1512 			    "Unsupported PHY mode %s !\n",
1513 			    phy_modes(phy_intf));
1514 	}
1515 
1516 	phydev = phy_find_first(priv->mii_bus);
1517 	if (!phydev) {
1518 		netdev_info(netdev, "%s: no PHY found\n", netdev->name);
1519 		return -ENODEV;
1520 	}
1521 
1522 	phydev = phy_connect(netdev, phydev_name(phydev),
1523 			     &ftgmac100_adjust_link, phy_intf);
1524 
1525 	if (IS_ERR(phydev)) {
1526 		netdev_err(netdev, "%s: Could not attach to PHY\n", netdev->name);
1527 		return PTR_ERR(phydev);
1528 	}
1529 
1530 	/* Indicate that we support PAUSE frames (see comment in
1531 	 * Documentation/networking/phy.rst)
1532 	 */
1533 	phy_support_asym_pause(phydev);
1534 
1535 	/* Display what we found */
1536 	phy_attached_info(phydev);
1537 
1538 	return 0;
1539 }
1540 
1541 static int ftgmac100_open(struct net_device *netdev)
1542 {
1543 	struct ftgmac100 *priv = netdev_priv(netdev);
1544 	int err;
1545 
1546 	/* Allocate ring buffers  */
1547 	err = ftgmac100_alloc_rings(priv);
1548 	if (err) {
1549 		netdev_err(netdev, "Failed to allocate descriptors\n");
1550 		return err;
1551 	}
1552 
1553 	/* When using NC-SI we force the speed to 100Mbit/s full duplex,
1554 	 *
1555 	 * Otherwise we leave it set to 0 (no link), the link
1556 	 * message from the PHY layer will handle setting it up to
1557 	 * something else if needed.
1558 	 */
1559 	if (priv->use_ncsi) {
1560 		priv->cur_duplex = DUPLEX_FULL;
1561 		priv->cur_speed = SPEED_100;
1562 	} else {
1563 		priv->cur_duplex = 0;
1564 		priv->cur_speed = 0;
1565 	}
1566 
1567 	/* Reset the hardware */
1568 	err = ftgmac100_reset_and_config_mac(priv);
1569 	if (err)
1570 		goto err_hw;
1571 
1572 	/* Initialize NAPI */
1573 	netif_napi_add(netdev, &priv->napi, ftgmac100_poll);
1574 
1575 	/* Grab our interrupt */
1576 	err = request_irq(netdev->irq, ftgmac100_interrupt, 0, netdev->name, netdev);
1577 	if (err) {
1578 		netdev_err(netdev, "failed to request irq %d\n", netdev->irq);
1579 		goto err_irq;
1580 	}
1581 
1582 	/* Start things up */
1583 	err = ftgmac100_init_all(priv, false);
1584 	if (err) {
1585 		netdev_err(netdev, "Failed to allocate packet buffers\n");
1586 		goto err_alloc;
1587 	}
1588 
1589 	if (netdev->phydev) {
1590 		/* If we have a PHY, start polling */
1591 		phy_start(netdev->phydev);
1592 	}
1593 	if (priv->use_ncsi) {
1594 		/* If using NC-SI, set our carrier on and start the stack */
1595 		netif_carrier_on(netdev);
1596 
1597 		/* Start the NCSI device */
1598 		err = ncsi_start_dev(priv->ndev);
1599 		if (err)
1600 			goto err_ncsi;
1601 	}
1602 
1603 	return 0;
1604 
1605 err_ncsi:
1606 	phy_stop(netdev->phydev);
1607 	napi_disable(&priv->napi);
1608 	netif_stop_queue(netdev);
1609 err_alloc:
1610 	ftgmac100_free_buffers(priv);
1611 	free_irq(netdev->irq, netdev);
1612 err_irq:
1613 	netif_napi_del(&priv->napi);
1614 err_hw:
1615 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1616 	ftgmac100_free_rings(priv);
1617 	return err;
1618 }
1619 
1620 static int ftgmac100_stop(struct net_device *netdev)
1621 {
1622 	struct ftgmac100 *priv = netdev_priv(netdev);
1623 
1624 	/* Note about the reset task: We are called with the rtnl lock
1625 	 * held, so we are synchronized against the core of the reset
1626 	 * task. We must not try to synchronously cancel it otherwise
1627 	 * we can deadlock. But since it will test for netif_running()
1628 	 * which has already been cleared by the net core, we don't
1629 	 * anything special to do.
1630 	 */
1631 
1632 	/* disable all interrupts */
1633 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1634 
1635 	netif_stop_queue(netdev);
1636 	napi_disable(&priv->napi);
1637 	netif_napi_del(&priv->napi);
1638 	if (netdev->phydev)
1639 		phy_stop(netdev->phydev);
1640 	if (priv->use_ncsi)
1641 		ncsi_stop_dev(priv->ndev);
1642 
1643 	ftgmac100_stop_hw(priv);
1644 	free_irq(netdev->irq, netdev);
1645 	ftgmac100_free_buffers(priv);
1646 	ftgmac100_free_rings(priv);
1647 
1648 	return 0;
1649 }
1650 
1651 static void ftgmac100_tx_timeout(struct net_device *netdev, unsigned int txqueue)
1652 {
1653 	struct ftgmac100 *priv = netdev_priv(netdev);
1654 
1655 	/* Disable all interrupts */
1656 	iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
1657 
1658 	/* Do the reset outside of interrupt context */
1659 	schedule_work(&priv->reset_task);
1660 }
1661 
1662 static int ftgmac100_set_features(struct net_device *netdev,
1663 				  netdev_features_t features)
1664 {
1665 	struct ftgmac100 *priv = netdev_priv(netdev);
1666 	netdev_features_t changed = netdev->features ^ features;
1667 
1668 	if (!netif_running(netdev))
1669 		return 0;
1670 
1671 	/* Update the vlan filtering bit */
1672 	if (changed & NETIF_F_HW_VLAN_CTAG_RX) {
1673 		u32 maccr;
1674 
1675 		maccr = ioread32(priv->base + FTGMAC100_OFFSET_MACCR);
1676 		if (priv->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
1677 			maccr |= FTGMAC100_MACCR_RM_VLAN;
1678 		else
1679 			maccr &= ~FTGMAC100_MACCR_RM_VLAN;
1680 		iowrite32(maccr, priv->base + FTGMAC100_OFFSET_MACCR);
1681 	}
1682 
1683 	return 0;
1684 }
1685 
1686 #ifdef CONFIG_NET_POLL_CONTROLLER
1687 static void ftgmac100_poll_controller(struct net_device *netdev)
1688 {
1689 	unsigned long flags;
1690 
1691 	local_irq_save(flags);
1692 	ftgmac100_interrupt(netdev->irq, netdev);
1693 	local_irq_restore(flags);
1694 }
1695 #endif
1696 
1697 static const struct net_device_ops ftgmac100_netdev_ops = {
1698 	.ndo_open		= ftgmac100_open,
1699 	.ndo_stop		= ftgmac100_stop,
1700 	.ndo_start_xmit		= ftgmac100_hard_start_xmit,
1701 	.ndo_set_mac_address	= ftgmac100_set_mac_addr,
1702 	.ndo_validate_addr	= eth_validate_addr,
1703 	.ndo_eth_ioctl		= phy_do_ioctl,
1704 	.ndo_tx_timeout		= ftgmac100_tx_timeout,
1705 	.ndo_set_rx_mode	= ftgmac100_set_rx_mode,
1706 	.ndo_set_features	= ftgmac100_set_features,
1707 #ifdef CONFIG_NET_POLL_CONTROLLER
1708 	.ndo_poll_controller	= ftgmac100_poll_controller,
1709 #endif
1710 	.ndo_vlan_rx_add_vid	= ncsi_vlan_rx_add_vid,
1711 	.ndo_vlan_rx_kill_vid	= ncsi_vlan_rx_kill_vid,
1712 };
1713 
1714 static int ftgmac100_setup_mdio(struct net_device *netdev)
1715 {
1716 	struct ftgmac100 *priv = netdev_priv(netdev);
1717 	struct platform_device *pdev = to_platform_device(priv->dev);
1718 	struct device_node *np = pdev->dev.of_node;
1719 	struct device_node *mdio_np;
1720 	int err = 0;
1721 	u32 reg;
1722 
1723 	/* initialize mdio bus */
1724 	priv->mii_bus = devm_mdiobus_alloc(priv->dev);
1725 	if (!priv->mii_bus)
1726 		return -EIO;
1727 
1728 	if (priv->mac_id == FTGMAC100_AST2400 ||
1729 	    priv->mac_id == FTGMAC100_AST2500) {
1730 		/* The AST2600 has a separate MDIO controller */
1731 
1732 		/* For the AST2400 and AST2500 this driver only supports the
1733 		 * old MDIO interface
1734 		 */
1735 		reg = ioread32(priv->base + FTGMAC100_OFFSET_REVR);
1736 		reg &= ~FTGMAC100_REVR_NEW_MDIO_INTERFACE;
1737 		iowrite32(reg, priv->base + FTGMAC100_OFFSET_REVR);
1738 	}
1739 
1740 	priv->mii_bus->name = "ftgmac100_mdio";
1741 	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%d",
1742 		 pdev->name, pdev->id);
1743 	priv->mii_bus->parent = priv->dev;
1744 	priv->mii_bus->priv = priv->netdev;
1745 	priv->mii_bus->read = ftgmac100_mdiobus_read;
1746 	priv->mii_bus->write = ftgmac100_mdiobus_write;
1747 
1748 	mdio_np = of_get_child_by_name(np, "mdio");
1749 
1750 	err = devm_of_mdiobus_register(priv->dev, priv->mii_bus, mdio_np);
1751 	of_node_put(mdio_np);
1752 	if (err) {
1753 		dev_err(priv->dev, "Cannot register MDIO bus!\n");
1754 		return err;
1755 	}
1756 
1757 	return 0;
1758 }
1759 
1760 static void ftgmac100_phy_disconnect(struct net_device *netdev)
1761 {
1762 	struct ftgmac100 *priv = netdev_priv(netdev);
1763 	struct phy_device *phydev = netdev->phydev;
1764 
1765 	if (!phydev)
1766 		return;
1767 
1768 	phy_disconnect(phydev);
1769 	if (of_phy_is_fixed_link(priv->dev->of_node))
1770 		of_phy_deregister_fixed_link(priv->dev->of_node);
1771 
1772 	if (priv->use_ncsi)
1773 		fixed_phy_unregister(phydev);
1774 }
1775 
1776 static void ftgmac100_ncsi_handler(struct ncsi_dev *nd)
1777 {
1778 	if (unlikely(nd->state != ncsi_dev_state_functional))
1779 		return;
1780 
1781 	netdev_dbg(nd->dev, "NCSI interface %s\n",
1782 		   nd->link_up ? "up" : "down");
1783 }
1784 
1785 static int ftgmac100_setup_clk(struct ftgmac100 *priv)
1786 {
1787 	struct clk *clk;
1788 	int rc;
1789 
1790 	clk = devm_clk_get_enabled(priv->dev, NULL /* MACCLK */);
1791 	if (IS_ERR(clk))
1792 		return PTR_ERR(clk);
1793 	priv->clk = clk;
1794 
1795 	/* Aspeed specifies a 100MHz clock is required for up to
1796 	 * 1000Mbit link speeds. As NCSI is limited to 100Mbit, 25MHz
1797 	 * is sufficient
1798 	 */
1799 	rc = clk_set_rate(priv->clk, priv->use_ncsi ? FTGMAC_25MHZ :
1800 			  FTGMAC_100MHZ);
1801 	if (rc)
1802 		return rc;
1803 
1804 	/* RCLK is for RMII, typically used for NCSI. Optional because it's not
1805 	 * necessary if it's the AST2400 MAC, or the MAC is configured for
1806 	 * RGMII, or the controller is not an ASPEED-based controller.
1807 	 */
1808 	priv->rclk = devm_clk_get_optional_enabled(priv->dev, "RCLK");
1809 	if (IS_ERR(priv->rclk))
1810 		return PTR_ERR(priv->rclk);
1811 
1812 	return 0;
1813 }
1814 
1815 static bool ftgmac100_has_child_node(struct device_node *np, const char *name)
1816 {
1817 	struct device_node *child_np = of_get_child_by_name(np, name);
1818 	bool ret = false;
1819 
1820 	if (child_np) {
1821 		ret = true;
1822 		of_node_put(child_np);
1823 	}
1824 
1825 	return ret;
1826 }
1827 
1828 static int ftgmac100_probe_ncsi(struct net_device *netdev,
1829 				struct ftgmac100 *priv,
1830 				struct platform_device *pdev)
1831 {
1832 	struct device_node *np = pdev->dev.of_node;
1833 	struct phy_device *phydev;
1834 	int err;
1835 
1836 	if (!IS_ENABLED(CONFIG_NET_NCSI)) {
1837 		dev_err(&pdev->dev, "NCSI stack not enabled\n");
1838 		return -EINVAL;
1839 	}
1840 
1841 	dev_info(&pdev->dev, "Using NCSI interface\n");
1842 	priv->use_ncsi = true;
1843 	priv->ndev = ncsi_register_dev(netdev, ftgmac100_ncsi_handler);
1844 	if (!priv->ndev)
1845 		return -EINVAL;
1846 
1847 	phydev = fixed_phy_register(&ncsi_phy_status, np);
1848 	if (IS_ERR(phydev)) {
1849 		dev_err(&pdev->dev, "failed to register fixed PHY device\n");
1850 		err = PTR_ERR(phydev);
1851 		goto err_register_ndev;
1852 	}
1853 	err = phy_connect_direct(netdev, phydev, ftgmac100_adjust_link,
1854 				 PHY_INTERFACE_MODE_RMII);
1855 	if (err) {
1856 		dev_err(&pdev->dev, "Connecting PHY failed\n");
1857 		goto err_register_phy;
1858 	}
1859 
1860 	return 0;
1861 err_register_phy:
1862 	fixed_phy_unregister(phydev);
1863 err_register_ndev:
1864 	if (priv->ndev)
1865 		ncsi_unregister_dev(priv->ndev);
1866 	priv->ndev = NULL;
1867 	return err;
1868 }
1869 
1870 static int ftgmac100_probe_dt(struct net_device *netdev,
1871 			      struct platform_device *pdev,
1872 			      struct ftgmac100 *priv,
1873 			      struct device_node *np)
1874 {
1875 	struct phy_device *phy;
1876 	int err;
1877 
1878 	if (of_get_property(np, "use-ncsi", NULL))
1879 		return ftgmac100_probe_ncsi(netdev, priv, pdev);
1880 
1881 	if (of_phy_is_fixed_link(np) ||
1882 	    of_get_property(np, "phy-handle", NULL)) {
1883 		/* Support "mdio"/"phy" child nodes for ast2400/2500
1884 		 * with an embedded MDIO controller. Automatically
1885 		 * scan the DTS for available PHYs and register
1886 		 * them. 2600 has an independent MDIO controller, not
1887 		 * part of the MAC.
1888 		 */
1889 		phy = of_phy_get_and_connect(priv->netdev, np,
1890 					     &ftgmac100_adjust_link);
1891 		if (!phy) {
1892 			dev_err(&pdev->dev, "Failed to connect to phy\n");
1893 			return -EINVAL;
1894 		}
1895 
1896 		/* Indicate that we support PAUSE frames (see comment in
1897 		 * Documentation/networking/phy.rst)
1898 		 */
1899 		phy_support_asym_pause(phy);
1900 
1901 		/* Display what we found */
1902 		phy_attached_info(phy);
1903 		return 0;
1904 	}
1905 
1906 	if (!ftgmac100_has_child_node(np, "mdio")) {
1907 		/* Support legacy ASPEED devicetree descriptions that
1908 		 * decribe a MAC with an embedded MDIO controller but
1909 		 * have no "mdio" child node. Automatically scan the
1910 		 * MDIO bus for available PHYs.
1911 		 */
1912 		err = ftgmac100_mii_probe(netdev);
1913 		if (err) {
1914 			dev_err(priv->dev, "MII probe failed!\n");
1915 			return err;
1916 		}
1917 	}
1918 
1919 	return 0;
1920 }
1921 
1922 static int ftgmac100_probe(struct platform_device *pdev)
1923 {
1924 	const struct ftgmac100_match_data *match_data;
1925 	enum ftgmac100_mac_id mac_id;
1926 	struct resource *res;
1927 	int irq;
1928 	struct net_device *netdev;
1929 	struct ftgmac100 *priv;
1930 	struct device_node *np;
1931 	int err = 0;
1932 
1933 	np = pdev->dev.of_node;
1934 	if (np) {
1935 		match_data = of_device_get_match_data(&pdev->dev);
1936 		if (!match_data)
1937 			return -EINVAL;
1938 		mac_id = match_data->mac_id;
1939 	} else {
1940 		mac_id = FTGMAC100_FARADAY;
1941 	}
1942 
1943 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1944 	if (!res)
1945 		return -ENXIO;
1946 
1947 	irq = platform_get_irq(pdev, 0);
1948 	if (irq < 0)
1949 		return irq;
1950 
1951 	/* setup net_device */
1952 	netdev = devm_alloc_etherdev(&pdev->dev, sizeof(*priv));
1953 	if (!netdev)
1954 		return -ENOMEM;
1955 
1956 	SET_NETDEV_DEV(netdev, &pdev->dev);
1957 
1958 	netdev->ethtool_ops = &ftgmac100_ethtool_ops;
1959 	netdev->netdev_ops = &ftgmac100_netdev_ops;
1960 	netdev->watchdog_timeo = 5 * HZ;
1961 
1962 	platform_set_drvdata(pdev, netdev);
1963 
1964 	/* setup private data */
1965 	priv = netdev_priv(netdev);
1966 	priv->netdev = netdev;
1967 	priv->dev = &pdev->dev;
1968 	priv->mac_id = mac_id;
1969 	INIT_WORK(&priv->reset_task, ftgmac100_reset_task);
1970 
1971 	/* map io memory */
1972 	priv->res = devm_request_mem_region(&pdev->dev,
1973 					    res->start, resource_size(res),
1974 					    dev_name(&pdev->dev));
1975 	if (!priv->res) {
1976 		dev_err(&pdev->dev, "Could not reserve memory region\n");
1977 		return -ENOMEM;
1978 	}
1979 
1980 	priv->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
1981 	if (!priv->base) {
1982 		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
1983 		return -EIO;
1984 	}
1985 
1986 	netdev->irq = irq;
1987 
1988 	/* Enable pause */
1989 	priv->tx_pause = true;
1990 	priv->rx_pause = true;
1991 	priv->aneg_pause = true;
1992 
1993 	/* MAC address from chip or random one */
1994 	err = ftgmac100_initial_mac(priv);
1995 	if (err)
1996 		return err;
1997 
1998 	if (priv->mac_id == FTGMAC100_AST2400 ||
1999 	    priv->mac_id == FTGMAC100_AST2500 ||
2000 	    priv->mac_id == FTGMAC100_AST2600) {
2001 		priv->rxdes0_edorr_mask = BIT(30);
2002 		priv->txdes0_edotr_mask = BIT(30);
2003 		priv->is_aspeed = true;
2004 	} else {
2005 		priv->rxdes0_edorr_mask = BIT(15);
2006 		priv->txdes0_edotr_mask = BIT(15);
2007 	}
2008 
2009 	if (priv->mac_id == FTGMAC100_FARADAY ||
2010 	    priv->mac_id == FTGMAC100_AST2400 ||
2011 	    priv->mac_id == FTGMAC100_AST2500) {
2012 		err = ftgmac100_setup_mdio(netdev);
2013 		if (err)
2014 			return err;
2015 	}
2016 
2017 	if (np) {
2018 		err = ftgmac100_probe_dt(netdev, pdev, priv, np);
2019 		if (err)
2020 			goto err;
2021 	}
2022 
2023 	priv->rst = devm_reset_control_get_optional_exclusive(priv->dev, NULL);
2024 	if (IS_ERR(priv->rst)) {
2025 		err = PTR_ERR(priv->rst);
2026 		goto err;
2027 	}
2028 
2029 	if (priv->is_aspeed) {
2030 		err = ftgmac100_setup_clk(priv);
2031 		if (err)
2032 			goto err;
2033 	}
2034 
2035 	/* Disable ast2600 problematic HW arbitration */
2036 	if (priv->mac_id == FTGMAC100_AST2600)
2037 		iowrite32(FTGMAC100_TM_DEFAULT,
2038 			  priv->base + FTGMAC100_OFFSET_TM);
2039 
2040 	/* Default ring sizes */
2041 	priv->rx_q_entries = priv->new_rx_q_entries = DEF_RX_QUEUE_ENTRIES;
2042 	priv->tx_q_entries = priv->new_tx_q_entries = DEF_TX_QUEUE_ENTRIES;
2043 
2044 	/* Base feature set */
2045 	netdev->hw_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM |
2046 		NETIF_F_GRO | NETIF_F_SG | NETIF_F_HW_VLAN_CTAG_RX |
2047 		NETIF_F_HW_VLAN_CTAG_TX;
2048 
2049 	if (priv->use_ncsi)
2050 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
2051 
2052 	/* AST2400  doesn't have working HW checksum generation */
2053 	if (priv->mac_id == FTGMAC100_AST2400)
2054 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
2055 
2056 	/* AST2600 tx checksum with NCSI is broken */
2057 	if (priv->use_ncsi && priv->mac_id == FTGMAC100_AST2600)
2058 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
2059 
2060 	if (np && of_get_property(np, "no-hw-checksum", NULL))
2061 		netdev->hw_features &= ~(NETIF_F_HW_CSUM | NETIF_F_RXCSUM);
2062 	netdev->features |= netdev->hw_features;
2063 
2064 	/* register network device */
2065 	err = register_netdev(netdev);
2066 	if (err) {
2067 		dev_err(&pdev->dev, "Failed to register netdev\n");
2068 		goto err;
2069 	}
2070 
2071 	netdev_info(netdev, "irq %d, mapped at %p\n", netdev->irq, priv->base);
2072 
2073 	return 0;
2074 
2075 err:
2076 	ftgmac100_phy_disconnect(netdev);
2077 	if (priv->ndev)
2078 		ncsi_unregister_dev(priv->ndev);
2079 	return err;
2080 }
2081 
2082 static void ftgmac100_remove(struct platform_device *pdev)
2083 {
2084 	struct net_device *netdev;
2085 	struct ftgmac100 *priv;
2086 
2087 	netdev = platform_get_drvdata(pdev);
2088 	priv = netdev_priv(netdev);
2089 
2090 	if (priv->ndev)
2091 		ncsi_unregister_dev(priv->ndev);
2092 	unregister_netdev(netdev);
2093 
2094 	/* There's a small chance the reset task will have been re-queued,
2095 	 * during stop, make sure it's gone before we free the structure.
2096 	 */
2097 	cancel_work_sync(&priv->reset_task);
2098 
2099 	ftgmac100_phy_disconnect(netdev);
2100 }
2101 
2102 static const struct ftgmac100_match_data ftgmac100_match_data_ast2400 = {
2103 	.mac_id = FTGMAC100_AST2400
2104 };
2105 
2106 static const struct ftgmac100_match_data ftgmac100_match_data_ast2500 = {
2107 	.mac_id = FTGMAC100_AST2500
2108 };
2109 
2110 static const struct ftgmac100_match_data ftgmac100_match_data_ast2600 = {
2111 	.mac_id = FTGMAC100_AST2600
2112 };
2113 
2114 static const struct ftgmac100_match_data ftgmac100_match_data_faraday = {
2115 	.mac_id = FTGMAC100_FARADAY
2116 };
2117 
2118 static const struct of_device_id ftgmac100_of_match[] = {
2119 	{ .compatible = "aspeed,ast2400-mac",
2120 	  .data = &ftgmac100_match_data_ast2400},
2121 	{ .compatible = "aspeed,ast2500-mac",
2122 	  .data = &ftgmac100_match_data_ast2500 },
2123 	{ .compatible = "aspeed,ast2600-mac",
2124 	  .data = &ftgmac100_match_data_ast2600 },
2125 	{ .compatible = "faraday,ftgmac100",
2126 	  .data = &ftgmac100_match_data_faraday },
2127 	{ }
2128 };
2129 MODULE_DEVICE_TABLE(of, ftgmac100_of_match);
2130 
2131 static struct platform_driver ftgmac100_driver = {
2132 	.probe	= ftgmac100_probe,
2133 	.remove = ftgmac100_remove,
2134 	.driver	= {
2135 		.name		= DRV_NAME,
2136 		.of_match_table	= ftgmac100_of_match,
2137 	},
2138 };
2139 module_platform_driver(ftgmac100_driver);
2140 
2141 MODULE_AUTHOR("Po-Yu Chuang <ratbert@faraday-tech.com>");
2142 MODULE_DESCRIPTION("FTGMAC100 driver");
2143 MODULE_LICENSE("GPL");
2144