xref: /openbmc/linux/drivers/net/ethernet/ni/nixge.c (revision 7587cdef)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2016-2017, National Instruments Corp.
3  *
4  * Author: Moritz Fischer <mdf@kernel.org>
5  */
6 
7 #include <linux/etherdevice.h>
8 #include <linux/module.h>
9 #include <linux/netdevice.h>
10 #include <linux/of_address.h>
11 #include <linux/of_mdio.h>
12 #include <linux/of_net.h>
13 #include <linux/of_platform.h>
14 #include <linux/of_irq.h>
15 #include <linux/skbuff.h>
16 #include <linux/phy.h>
17 #include <linux/mii.h>
18 #include <linux/nvmem-consumer.h>
19 #include <linux/ethtool.h>
20 #include <linux/iopoll.h>
21 
22 #define TX_BD_NUM		64
23 #define RX_BD_NUM		128
24 
25 /* Axi DMA Register definitions */
26 #define XAXIDMA_TX_CR_OFFSET	0x00 /* Channel control */
27 #define XAXIDMA_TX_SR_OFFSET	0x04 /* Status */
28 #define XAXIDMA_TX_CDESC_OFFSET	0x08 /* Current descriptor pointer */
29 #define XAXIDMA_TX_TDESC_OFFSET	0x10 /* Tail descriptor pointer */
30 
31 #define XAXIDMA_RX_CR_OFFSET	0x30 /* Channel control */
32 #define XAXIDMA_RX_SR_OFFSET	0x34 /* Status */
33 #define XAXIDMA_RX_CDESC_OFFSET	0x38 /* Current descriptor pointer */
34 #define XAXIDMA_RX_TDESC_OFFSET	0x40 /* Tail descriptor pointer */
35 
36 #define XAXIDMA_CR_RUNSTOP_MASK	0x1 /* Start/stop DMA channel */
37 #define XAXIDMA_CR_RESET_MASK	0x4 /* Reset DMA engine */
38 
39 #define XAXIDMA_BD_CTRL_LENGTH_MASK	0x007FFFFF /* Requested len */
40 #define XAXIDMA_BD_CTRL_TXSOF_MASK	0x08000000 /* First tx packet */
41 #define XAXIDMA_BD_CTRL_TXEOF_MASK	0x04000000 /* Last tx packet */
42 #define XAXIDMA_BD_CTRL_ALL_MASK	0x0C000000 /* All control bits */
43 
44 #define XAXIDMA_DELAY_MASK		0xFF000000 /* Delay timeout counter */
45 #define XAXIDMA_COALESCE_MASK		0x00FF0000 /* Coalesce counter */
46 
47 #define XAXIDMA_DELAY_SHIFT		24
48 #define XAXIDMA_COALESCE_SHIFT		16
49 
50 #define XAXIDMA_IRQ_IOC_MASK		0x00001000 /* Completion intr */
51 #define XAXIDMA_IRQ_DELAY_MASK		0x00002000 /* Delay interrupt */
52 #define XAXIDMA_IRQ_ERROR_MASK		0x00004000 /* Error interrupt */
53 #define XAXIDMA_IRQ_ALL_MASK		0x00007000 /* All interrupts */
54 
55 /* Default TX/RX Threshold and waitbound values for SGDMA mode */
56 #define XAXIDMA_DFT_TX_THRESHOLD	24
57 #define XAXIDMA_DFT_TX_WAITBOUND	254
58 #define XAXIDMA_DFT_RX_THRESHOLD	24
59 #define XAXIDMA_DFT_RX_WAITBOUND	254
60 
61 #define XAXIDMA_BD_STS_ACTUAL_LEN_MASK	0x007FFFFF /* Actual len */
62 #define XAXIDMA_BD_STS_COMPLETE_MASK	0x80000000 /* Completed */
63 #define XAXIDMA_BD_STS_DEC_ERR_MASK	0x40000000 /* Decode error */
64 #define XAXIDMA_BD_STS_SLV_ERR_MASK	0x20000000 /* Slave error */
65 #define XAXIDMA_BD_STS_INT_ERR_MASK	0x10000000 /* Internal err */
66 #define XAXIDMA_BD_STS_ALL_ERR_MASK	0x70000000 /* All errors */
67 #define XAXIDMA_BD_STS_RXSOF_MASK	0x08000000 /* First rx pkt */
68 #define XAXIDMA_BD_STS_RXEOF_MASK	0x04000000 /* Last rx pkt */
69 #define XAXIDMA_BD_STS_ALL_MASK		0xFC000000 /* All status bits */
70 
71 #define NIXGE_REG_CTRL_OFFSET	0x4000
72 #define NIXGE_REG_INFO		0x00
73 #define NIXGE_REG_MAC_CTL	0x04
74 #define NIXGE_REG_PHY_CTL	0x08
75 #define NIXGE_REG_LED_CTL	0x0c
76 #define NIXGE_REG_MDIO_DATA	0x10
77 #define NIXGE_REG_MDIO_ADDR	0x14
78 #define NIXGE_REG_MDIO_OP	0x18
79 #define NIXGE_REG_MDIO_CTRL	0x1c
80 
81 #define NIXGE_ID_LED_CTL_EN	BIT(0)
82 #define NIXGE_ID_LED_CTL_VAL	BIT(1)
83 
84 #define NIXGE_MDIO_CLAUSE45	BIT(12)
85 #define NIXGE_MDIO_CLAUSE22	0
86 #define NIXGE_MDIO_OP(n)     (((n) & 0x3) << 10)
87 #define NIXGE_MDIO_OP_ADDRESS	0
88 #define NIXGE_MDIO_C45_WRITE	BIT(0)
89 #define NIXGE_MDIO_C45_READ	(BIT(1) | BIT(0))
90 #define NIXGE_MDIO_C22_WRITE	BIT(0)
91 #define NIXGE_MDIO_C22_READ	BIT(1)
92 #define NIXGE_MDIO_ADDR(n)   (((n) & 0x1f) << 5)
93 #define NIXGE_MDIO_MMD(n)    (((n) & 0x1f) << 0)
94 
95 #define NIXGE_REG_MAC_LSB	0x1000
96 #define NIXGE_REG_MAC_MSB	0x1004
97 
98 /* Packet size info */
99 #define NIXGE_HDR_SIZE		14 /* Size of Ethernet header */
100 #define NIXGE_TRL_SIZE		4 /* Size of Ethernet trailer (FCS) */
101 #define NIXGE_MTU		1500 /* Max MTU of an Ethernet frame */
102 #define NIXGE_JUMBO_MTU		9000 /* Max MTU of a jumbo Eth. frame */
103 
104 #define NIXGE_MAX_FRAME_SIZE	 (NIXGE_MTU + NIXGE_HDR_SIZE + NIXGE_TRL_SIZE)
105 #define NIXGE_MAX_JUMBO_FRAME_SIZE \
106 	(NIXGE_JUMBO_MTU + NIXGE_HDR_SIZE + NIXGE_TRL_SIZE)
107 
108 enum nixge_version {
109 	NIXGE_V2,
110 	NIXGE_V3,
111 	NIXGE_VERSION_COUNT
112 };
113 
114 struct nixge_hw_dma_bd {
115 	u32 next_lo;
116 	u32 next_hi;
117 	u32 phys_lo;
118 	u32 phys_hi;
119 	u32 reserved3;
120 	u32 reserved4;
121 	u32 cntrl;
122 	u32 status;
123 	u32 app0;
124 	u32 app1;
125 	u32 app2;
126 	u32 app3;
127 	u32 app4;
128 	u32 sw_id_offset_lo;
129 	u32 sw_id_offset_hi;
130 	u32 reserved6;
131 };
132 
133 #ifdef CONFIG_PHYS_ADDR_T_64BIT
134 #define nixge_hw_dma_bd_set_addr(bd, field, addr) \
135 	do { \
136 		(bd)->field##_lo = lower_32_bits((addr)); \
137 		(bd)->field##_hi = upper_32_bits((addr)); \
138 	} while (0)
139 #else
140 #define nixge_hw_dma_bd_set_addr(bd, field, addr) \
141 	((bd)->field##_lo = lower_32_bits((addr)))
142 #endif
143 
144 #define nixge_hw_dma_bd_set_phys(bd, addr) \
145 	nixge_hw_dma_bd_set_addr((bd), phys, (addr))
146 
147 #define nixge_hw_dma_bd_set_next(bd, addr) \
148 	nixge_hw_dma_bd_set_addr((bd), next, (addr))
149 
150 #define nixge_hw_dma_bd_set_offset(bd, addr) \
151 	nixge_hw_dma_bd_set_addr((bd), sw_id_offset, (addr))
152 
153 #ifdef CONFIG_PHYS_ADDR_T_64BIT
154 #define nixge_hw_dma_bd_get_addr(bd, field) \
155 	(dma_addr_t)((((u64)(bd)->field##_hi) << 32) | ((bd)->field##_lo))
156 #else
157 #define nixge_hw_dma_bd_get_addr(bd, field) \
158 	(dma_addr_t)((bd)->field##_lo)
159 #endif
160 
161 struct nixge_tx_skb {
162 	struct sk_buff *skb;
163 	dma_addr_t mapping;
164 	size_t size;
165 	bool mapped_as_page;
166 };
167 
168 struct nixge_priv {
169 	struct net_device *ndev;
170 	struct napi_struct napi;
171 	struct device *dev;
172 
173 	/* Connection to PHY device */
174 	struct device_node *phy_node;
175 	phy_interface_t		phy_mode;
176 
177 	int link;
178 	unsigned int speed;
179 	unsigned int duplex;
180 
181 	/* MDIO bus data */
182 	struct mii_bus *mii_bus;	/* MII bus reference */
183 
184 	/* IO registers, dma functions and IRQs */
185 	void __iomem *ctrl_regs;
186 	void __iomem *dma_regs;
187 
188 	struct tasklet_struct dma_err_tasklet;
189 
190 	int tx_irq;
191 	int rx_irq;
192 
193 	/* Buffer descriptors */
194 	struct nixge_hw_dma_bd *tx_bd_v;
195 	struct nixge_tx_skb *tx_skb;
196 	dma_addr_t tx_bd_p;
197 
198 	struct nixge_hw_dma_bd *rx_bd_v;
199 	dma_addr_t rx_bd_p;
200 	u32 tx_bd_ci;
201 	u32 tx_bd_tail;
202 	u32 rx_bd_ci;
203 
204 	u32 coalesce_count_rx;
205 	u32 coalesce_count_tx;
206 };
207 
208 static void nixge_dma_write_reg(struct nixge_priv *priv, off_t offset, u32 val)
209 {
210 	writel(val, priv->dma_regs + offset);
211 }
212 
213 static void nixge_dma_write_desc_reg(struct nixge_priv *priv, off_t offset,
214 				     dma_addr_t addr)
215 {
216 	writel(lower_32_bits(addr), priv->dma_regs + offset);
217 #ifdef CONFIG_PHYS_ADDR_T_64BIT
218 	writel(upper_32_bits(addr), priv->dma_regs + offset + 4);
219 #endif
220 }
221 
222 static u32 nixge_dma_read_reg(const struct nixge_priv *priv, off_t offset)
223 {
224 	return readl(priv->dma_regs + offset);
225 }
226 
227 static void nixge_ctrl_write_reg(struct nixge_priv *priv, off_t offset, u32 val)
228 {
229 	writel(val, priv->ctrl_regs + offset);
230 }
231 
232 static u32 nixge_ctrl_read_reg(struct nixge_priv *priv, off_t offset)
233 {
234 	return readl(priv->ctrl_regs + offset);
235 }
236 
237 #define nixge_ctrl_poll_timeout(priv, addr, val, cond, sleep_us, timeout_us) \
238 	readl_poll_timeout((priv)->ctrl_regs + (addr), (val), (cond), \
239 			   (sleep_us), (timeout_us))
240 
241 #define nixge_dma_poll_timeout(priv, addr, val, cond, sleep_us, timeout_us) \
242 	readl_poll_timeout((priv)->dma_regs + (addr), (val), (cond), \
243 			   (sleep_us), (timeout_us))
244 
245 static void nixge_hw_dma_bd_release(struct net_device *ndev)
246 {
247 	struct nixge_priv *priv = netdev_priv(ndev);
248 	dma_addr_t phys_addr;
249 	struct sk_buff *skb;
250 	int i;
251 
252 	for (i = 0; i < RX_BD_NUM; i++) {
253 		phys_addr = nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
254 						     phys);
255 
256 		dma_unmap_single(ndev->dev.parent, phys_addr,
257 				 NIXGE_MAX_JUMBO_FRAME_SIZE,
258 				 DMA_FROM_DEVICE);
259 
260 		skb = (struct sk_buff *)(uintptr_t)
261 			nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
262 						 sw_id_offset);
263 		dev_kfree_skb(skb);
264 	}
265 
266 	if (priv->rx_bd_v)
267 		dma_free_coherent(ndev->dev.parent,
268 				  sizeof(*priv->rx_bd_v) * RX_BD_NUM,
269 				  priv->rx_bd_v,
270 				  priv->rx_bd_p);
271 
272 	if (priv->tx_skb)
273 		devm_kfree(ndev->dev.parent, priv->tx_skb);
274 
275 	if (priv->tx_bd_v)
276 		dma_free_coherent(ndev->dev.parent,
277 				  sizeof(*priv->tx_bd_v) * TX_BD_NUM,
278 				  priv->tx_bd_v,
279 				  priv->tx_bd_p);
280 }
281 
282 static int nixge_hw_dma_bd_init(struct net_device *ndev)
283 {
284 	struct nixge_priv *priv = netdev_priv(ndev);
285 	struct sk_buff *skb;
286 	dma_addr_t phys;
287 	u32 cr;
288 	int i;
289 
290 	/* Reset the indexes which are used for accessing the BDs */
291 	priv->tx_bd_ci = 0;
292 	priv->tx_bd_tail = 0;
293 	priv->rx_bd_ci = 0;
294 
295 	/* Allocate the Tx and Rx buffer descriptors. */
296 	priv->tx_bd_v = dma_alloc_coherent(ndev->dev.parent,
297 					   sizeof(*priv->tx_bd_v) * TX_BD_NUM,
298 					   &priv->tx_bd_p, GFP_KERNEL);
299 	if (!priv->tx_bd_v)
300 		goto out;
301 
302 	priv->tx_skb = devm_kcalloc(ndev->dev.parent,
303 				    TX_BD_NUM, sizeof(*priv->tx_skb),
304 				    GFP_KERNEL);
305 	if (!priv->tx_skb)
306 		goto out;
307 
308 	priv->rx_bd_v = dma_alloc_coherent(ndev->dev.parent,
309 					   sizeof(*priv->rx_bd_v) * RX_BD_NUM,
310 					   &priv->rx_bd_p, GFP_KERNEL);
311 	if (!priv->rx_bd_v)
312 		goto out;
313 
314 	for (i = 0; i < TX_BD_NUM; i++) {
315 		nixge_hw_dma_bd_set_next(&priv->tx_bd_v[i],
316 					 priv->tx_bd_p +
317 					 sizeof(*priv->tx_bd_v) *
318 					 ((i + 1) % TX_BD_NUM));
319 	}
320 
321 	for (i = 0; i < RX_BD_NUM; i++) {
322 		nixge_hw_dma_bd_set_next(&priv->rx_bd_v[i],
323 					 priv->rx_bd_p
324 					 + sizeof(*priv->rx_bd_v) *
325 					 ((i + 1) % RX_BD_NUM));
326 
327 		skb = __netdev_alloc_skb_ip_align(ndev,
328 						  NIXGE_MAX_JUMBO_FRAME_SIZE,
329 						  GFP_KERNEL);
330 		if (!skb)
331 			goto out;
332 
333 		nixge_hw_dma_bd_set_offset(&priv->rx_bd_v[i], (uintptr_t)skb);
334 		phys = dma_map_single(ndev->dev.parent, skb->data,
335 				      NIXGE_MAX_JUMBO_FRAME_SIZE,
336 				      DMA_FROM_DEVICE);
337 
338 		nixge_hw_dma_bd_set_phys(&priv->rx_bd_v[i], phys);
339 
340 		priv->rx_bd_v[i].cntrl = NIXGE_MAX_JUMBO_FRAME_SIZE;
341 	}
342 
343 	/* Start updating the Rx channel control register */
344 	cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
345 	/* Update the interrupt coalesce count */
346 	cr = ((cr & ~XAXIDMA_COALESCE_MASK) |
347 	      ((priv->coalesce_count_rx) << XAXIDMA_COALESCE_SHIFT));
348 	/* Update the delay timer count */
349 	cr = ((cr & ~XAXIDMA_DELAY_MASK) |
350 	      (XAXIDMA_DFT_RX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
351 	/* Enable coalesce, delay timer and error interrupts */
352 	cr |= XAXIDMA_IRQ_ALL_MASK;
353 	/* Write to the Rx channel control register */
354 	nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
355 
356 	/* Start updating the Tx channel control register */
357 	cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
358 	/* Update the interrupt coalesce count */
359 	cr = (((cr & ~XAXIDMA_COALESCE_MASK)) |
360 	      ((priv->coalesce_count_tx) << XAXIDMA_COALESCE_SHIFT));
361 	/* Update the delay timer count */
362 	cr = (((cr & ~XAXIDMA_DELAY_MASK)) |
363 	      (XAXIDMA_DFT_TX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
364 	/* Enable coalesce, delay timer and error interrupts */
365 	cr |= XAXIDMA_IRQ_ALL_MASK;
366 	/* Write to the Tx channel control register */
367 	nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET, cr);
368 
369 	/* Populate the tail pointer and bring the Rx Axi DMA engine out of
370 	 * halted state. This will make the Rx side ready for reception.
371 	 */
372 	nixge_dma_write_desc_reg(priv, XAXIDMA_RX_CDESC_OFFSET, priv->rx_bd_p);
373 	cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
374 	nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET,
375 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
376 	nixge_dma_write_desc_reg(priv, XAXIDMA_RX_TDESC_OFFSET, priv->rx_bd_p +
377 			    (sizeof(*priv->rx_bd_v) * (RX_BD_NUM - 1)));
378 
379 	/* Write to the RS (Run-stop) bit in the Tx channel control register.
380 	 * Tx channel is now ready to run. But only after we write to the
381 	 * tail pointer register that the Tx channel will start transmitting.
382 	 */
383 	nixge_dma_write_desc_reg(priv, XAXIDMA_TX_CDESC_OFFSET, priv->tx_bd_p);
384 	cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
385 	nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET,
386 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
387 
388 	return 0;
389 out:
390 	nixge_hw_dma_bd_release(ndev);
391 	return -ENOMEM;
392 }
393 
394 static void __nixge_device_reset(struct nixge_priv *priv, off_t offset)
395 {
396 	u32 status;
397 	int err;
398 
399 	/* Reset Axi DMA. This would reset NIXGE Ethernet core as well.
400 	 * The reset process of Axi DMA takes a while to complete as all
401 	 * pending commands/transfers will be flushed or completed during
402 	 * this reset process.
403 	 */
404 	nixge_dma_write_reg(priv, offset, XAXIDMA_CR_RESET_MASK);
405 	err = nixge_dma_poll_timeout(priv, offset, status,
406 				     !(status & XAXIDMA_CR_RESET_MASK), 10,
407 				     1000);
408 	if (err)
409 		netdev_err(priv->ndev, "%s: DMA reset timeout!\n", __func__);
410 }
411 
412 static void nixge_device_reset(struct net_device *ndev)
413 {
414 	struct nixge_priv *priv = netdev_priv(ndev);
415 
416 	__nixge_device_reset(priv, XAXIDMA_TX_CR_OFFSET);
417 	__nixge_device_reset(priv, XAXIDMA_RX_CR_OFFSET);
418 
419 	if (nixge_hw_dma_bd_init(ndev))
420 		netdev_err(ndev, "%s: descriptor allocation failed\n",
421 			   __func__);
422 
423 	netif_trans_update(ndev);
424 }
425 
426 static void nixge_handle_link_change(struct net_device *ndev)
427 {
428 	struct nixge_priv *priv = netdev_priv(ndev);
429 	struct phy_device *phydev = ndev->phydev;
430 
431 	if (phydev->link != priv->link || phydev->speed != priv->speed ||
432 	    phydev->duplex != priv->duplex) {
433 		priv->link = phydev->link;
434 		priv->speed = phydev->speed;
435 		priv->duplex = phydev->duplex;
436 		phy_print_status(phydev);
437 	}
438 }
439 
440 static void nixge_tx_skb_unmap(struct nixge_priv *priv,
441 			       struct nixge_tx_skb *tx_skb)
442 {
443 	if (tx_skb->mapping) {
444 		if (tx_skb->mapped_as_page)
445 			dma_unmap_page(priv->ndev->dev.parent, tx_skb->mapping,
446 				       tx_skb->size, DMA_TO_DEVICE);
447 		else
448 			dma_unmap_single(priv->ndev->dev.parent,
449 					 tx_skb->mapping,
450 					 tx_skb->size, DMA_TO_DEVICE);
451 		tx_skb->mapping = 0;
452 	}
453 
454 	if (tx_skb->skb) {
455 		dev_kfree_skb_any(tx_skb->skb);
456 		tx_skb->skb = NULL;
457 	}
458 }
459 
460 static void nixge_start_xmit_done(struct net_device *ndev)
461 {
462 	struct nixge_priv *priv = netdev_priv(ndev);
463 	struct nixge_hw_dma_bd *cur_p;
464 	struct nixge_tx_skb *tx_skb;
465 	unsigned int status = 0;
466 	u32 packets = 0;
467 	u32 size = 0;
468 
469 	cur_p = &priv->tx_bd_v[priv->tx_bd_ci];
470 	tx_skb = &priv->tx_skb[priv->tx_bd_ci];
471 
472 	status = cur_p->status;
473 
474 	while (status & XAXIDMA_BD_STS_COMPLETE_MASK) {
475 		nixge_tx_skb_unmap(priv, tx_skb);
476 		cur_p->status = 0;
477 
478 		size += status & XAXIDMA_BD_STS_ACTUAL_LEN_MASK;
479 		packets++;
480 
481 		++priv->tx_bd_ci;
482 		priv->tx_bd_ci %= TX_BD_NUM;
483 		cur_p = &priv->tx_bd_v[priv->tx_bd_ci];
484 		tx_skb = &priv->tx_skb[priv->tx_bd_ci];
485 		status = cur_p->status;
486 	}
487 
488 	ndev->stats.tx_packets += packets;
489 	ndev->stats.tx_bytes += size;
490 
491 	if (packets)
492 		netif_wake_queue(ndev);
493 }
494 
495 static int nixge_check_tx_bd_space(struct nixge_priv *priv,
496 				   int num_frag)
497 {
498 	struct nixge_hw_dma_bd *cur_p;
499 
500 	cur_p = &priv->tx_bd_v[(priv->tx_bd_tail + num_frag) % TX_BD_NUM];
501 	if (cur_p->status & XAXIDMA_BD_STS_ALL_MASK)
502 		return NETDEV_TX_BUSY;
503 	return 0;
504 }
505 
506 static netdev_tx_t nixge_start_xmit(struct sk_buff *skb,
507 				    struct net_device *ndev)
508 {
509 	struct nixge_priv *priv = netdev_priv(ndev);
510 	struct nixge_hw_dma_bd *cur_p;
511 	struct nixge_tx_skb *tx_skb;
512 	dma_addr_t tail_p, cur_phys;
513 	skb_frag_t *frag;
514 	u32 num_frag;
515 	u32 ii;
516 
517 	num_frag = skb_shinfo(skb)->nr_frags;
518 	cur_p = &priv->tx_bd_v[priv->tx_bd_tail];
519 	tx_skb = &priv->tx_skb[priv->tx_bd_tail];
520 
521 	if (nixge_check_tx_bd_space(priv, num_frag)) {
522 		if (!netif_queue_stopped(ndev))
523 			netif_stop_queue(ndev);
524 		return NETDEV_TX_OK;
525 	}
526 
527 	cur_phys = dma_map_single(ndev->dev.parent, skb->data,
528 				  skb_headlen(skb), DMA_TO_DEVICE);
529 	if (dma_mapping_error(ndev->dev.parent, cur_phys))
530 		goto drop;
531 	nixge_hw_dma_bd_set_phys(cur_p, cur_phys);
532 
533 	cur_p->cntrl = skb_headlen(skb) | XAXIDMA_BD_CTRL_TXSOF_MASK;
534 
535 	tx_skb->skb = NULL;
536 	tx_skb->mapping = cur_phys;
537 	tx_skb->size = skb_headlen(skb);
538 	tx_skb->mapped_as_page = false;
539 
540 	for (ii = 0; ii < num_frag; ii++) {
541 		++priv->tx_bd_tail;
542 		priv->tx_bd_tail %= TX_BD_NUM;
543 		cur_p = &priv->tx_bd_v[priv->tx_bd_tail];
544 		tx_skb = &priv->tx_skb[priv->tx_bd_tail];
545 		frag = &skb_shinfo(skb)->frags[ii];
546 
547 		cur_phys = skb_frag_dma_map(ndev->dev.parent, frag, 0,
548 					    skb_frag_size(frag),
549 					    DMA_TO_DEVICE);
550 		if (dma_mapping_error(ndev->dev.parent, cur_phys))
551 			goto frag_err;
552 		nixge_hw_dma_bd_set_phys(cur_p, cur_phys);
553 
554 		cur_p->cntrl = skb_frag_size(frag);
555 
556 		tx_skb->skb = NULL;
557 		tx_skb->mapping = cur_phys;
558 		tx_skb->size = skb_frag_size(frag);
559 		tx_skb->mapped_as_page = true;
560 	}
561 
562 	/* last buffer of the frame */
563 	tx_skb->skb = skb;
564 
565 	cur_p->cntrl |= XAXIDMA_BD_CTRL_TXEOF_MASK;
566 
567 	tail_p = priv->tx_bd_p + sizeof(*priv->tx_bd_v) * priv->tx_bd_tail;
568 	/* Start the transfer */
569 	nixge_dma_write_desc_reg(priv, XAXIDMA_TX_TDESC_OFFSET, tail_p);
570 	++priv->tx_bd_tail;
571 	priv->tx_bd_tail %= TX_BD_NUM;
572 
573 	return NETDEV_TX_OK;
574 frag_err:
575 	for (; ii > 0; ii--) {
576 		if (priv->tx_bd_tail)
577 			priv->tx_bd_tail--;
578 		else
579 			priv->tx_bd_tail = TX_BD_NUM - 1;
580 
581 		tx_skb = &priv->tx_skb[priv->tx_bd_tail];
582 		nixge_tx_skb_unmap(priv, tx_skb);
583 
584 		cur_p = &priv->tx_bd_v[priv->tx_bd_tail];
585 		cur_p->status = 0;
586 	}
587 	dma_unmap_single(priv->ndev->dev.parent,
588 			 tx_skb->mapping,
589 			 tx_skb->size, DMA_TO_DEVICE);
590 drop:
591 	ndev->stats.tx_dropped++;
592 	return NETDEV_TX_OK;
593 }
594 
595 static int nixge_recv(struct net_device *ndev, int budget)
596 {
597 	struct nixge_priv *priv = netdev_priv(ndev);
598 	struct sk_buff *skb, *new_skb;
599 	struct nixge_hw_dma_bd *cur_p;
600 	dma_addr_t tail_p = 0, cur_phys = 0;
601 	u32 packets = 0;
602 	u32 length = 0;
603 	u32 size = 0;
604 
605 	cur_p = &priv->rx_bd_v[priv->rx_bd_ci];
606 
607 	while ((cur_p->status & XAXIDMA_BD_STS_COMPLETE_MASK &&
608 		budget > packets)) {
609 		tail_p = priv->rx_bd_p + sizeof(*priv->rx_bd_v) *
610 			 priv->rx_bd_ci;
611 
612 		skb = (struct sk_buff *)(uintptr_t)
613 			nixge_hw_dma_bd_get_addr(cur_p, sw_id_offset);
614 
615 		length = cur_p->status & XAXIDMA_BD_STS_ACTUAL_LEN_MASK;
616 		if (length > NIXGE_MAX_JUMBO_FRAME_SIZE)
617 			length = NIXGE_MAX_JUMBO_FRAME_SIZE;
618 
619 		dma_unmap_single(ndev->dev.parent,
620 				 nixge_hw_dma_bd_get_addr(cur_p, phys),
621 				 NIXGE_MAX_JUMBO_FRAME_SIZE,
622 				 DMA_FROM_DEVICE);
623 
624 		skb_put(skb, length);
625 
626 		skb->protocol = eth_type_trans(skb, ndev);
627 		skb_checksum_none_assert(skb);
628 
629 		/* For now mark them as CHECKSUM_NONE since
630 		 * we don't have offload capabilities
631 		 */
632 		skb->ip_summed = CHECKSUM_NONE;
633 
634 		napi_gro_receive(&priv->napi, skb);
635 
636 		size += length;
637 		packets++;
638 
639 		new_skb = netdev_alloc_skb_ip_align(ndev,
640 						    NIXGE_MAX_JUMBO_FRAME_SIZE);
641 		if (!new_skb)
642 			return packets;
643 
644 		cur_phys = dma_map_single(ndev->dev.parent, new_skb->data,
645 					  NIXGE_MAX_JUMBO_FRAME_SIZE,
646 					  DMA_FROM_DEVICE);
647 		if (dma_mapping_error(ndev->dev.parent, cur_phys)) {
648 			/* FIXME: bail out and clean up */
649 			netdev_err(ndev, "Failed to map ...\n");
650 		}
651 		nixge_hw_dma_bd_set_phys(cur_p, cur_phys);
652 		cur_p->cntrl = NIXGE_MAX_JUMBO_FRAME_SIZE;
653 		cur_p->status = 0;
654 		nixge_hw_dma_bd_set_offset(cur_p, (uintptr_t)new_skb);
655 
656 		++priv->rx_bd_ci;
657 		priv->rx_bd_ci %= RX_BD_NUM;
658 		cur_p = &priv->rx_bd_v[priv->rx_bd_ci];
659 	}
660 
661 	ndev->stats.rx_packets += packets;
662 	ndev->stats.rx_bytes += size;
663 
664 	if (tail_p)
665 		nixge_dma_write_desc_reg(priv, XAXIDMA_RX_TDESC_OFFSET, tail_p);
666 
667 	return packets;
668 }
669 
670 static int nixge_poll(struct napi_struct *napi, int budget)
671 {
672 	struct nixge_priv *priv = container_of(napi, struct nixge_priv, napi);
673 	int work_done;
674 	u32 status, cr;
675 
676 	work_done = 0;
677 
678 	work_done = nixge_recv(priv->ndev, budget);
679 	if (work_done < budget) {
680 		napi_complete_done(napi, work_done);
681 		status = nixge_dma_read_reg(priv, XAXIDMA_RX_SR_OFFSET);
682 
683 		if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
684 			/* If there's more, reschedule, but clear */
685 			nixge_dma_write_reg(priv, XAXIDMA_RX_SR_OFFSET, status);
686 			napi_reschedule(napi);
687 		} else {
688 			/* if not, turn on RX IRQs again ... */
689 			cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
690 			cr |= (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK);
691 			nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
692 		}
693 	}
694 
695 	return work_done;
696 }
697 
698 static irqreturn_t nixge_tx_irq(int irq, void *_ndev)
699 {
700 	struct nixge_priv *priv = netdev_priv(_ndev);
701 	struct net_device *ndev = _ndev;
702 	unsigned int status;
703 	dma_addr_t phys;
704 	u32 cr;
705 
706 	status = nixge_dma_read_reg(priv, XAXIDMA_TX_SR_OFFSET);
707 	if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
708 		nixge_dma_write_reg(priv, XAXIDMA_TX_SR_OFFSET, status);
709 		nixge_start_xmit_done(priv->ndev);
710 		goto out;
711 	}
712 	if (!(status & XAXIDMA_IRQ_ALL_MASK)) {
713 		netdev_err(ndev, "No interrupts asserted in Tx path\n");
714 		return IRQ_NONE;
715 	}
716 	if (status & XAXIDMA_IRQ_ERROR_MASK) {
717 		phys = nixge_hw_dma_bd_get_addr(&priv->tx_bd_v[priv->tx_bd_ci],
718 						phys);
719 
720 		netdev_err(ndev, "DMA Tx error 0x%x\n", status);
721 		netdev_err(ndev, "Current BD is at: 0x%llx\n", (u64)phys);
722 
723 		cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
724 		/* Disable coalesce, delay timer and error interrupts */
725 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
726 		/* Write to the Tx channel control register */
727 		nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET, cr);
728 
729 		cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
730 		/* Disable coalesce, delay timer and error interrupts */
731 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
732 		/* Write to the Rx channel control register */
733 		nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
734 
735 		tasklet_schedule(&priv->dma_err_tasklet);
736 		nixge_dma_write_reg(priv, XAXIDMA_TX_SR_OFFSET, status);
737 	}
738 out:
739 	return IRQ_HANDLED;
740 }
741 
742 static irqreturn_t nixge_rx_irq(int irq, void *_ndev)
743 {
744 	struct nixge_priv *priv = netdev_priv(_ndev);
745 	struct net_device *ndev = _ndev;
746 	unsigned int status;
747 	dma_addr_t phys;
748 	u32 cr;
749 
750 	status = nixge_dma_read_reg(priv, XAXIDMA_RX_SR_OFFSET);
751 	if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
752 		/* Turn of IRQs because NAPI */
753 		nixge_dma_write_reg(priv, XAXIDMA_RX_SR_OFFSET, status);
754 		cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
755 		cr &= ~(XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK);
756 		nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
757 
758 		if (napi_schedule_prep(&priv->napi))
759 			__napi_schedule(&priv->napi);
760 		goto out;
761 	}
762 	if (!(status & XAXIDMA_IRQ_ALL_MASK)) {
763 		netdev_err(ndev, "No interrupts asserted in Rx path\n");
764 		return IRQ_NONE;
765 	}
766 	if (status & XAXIDMA_IRQ_ERROR_MASK) {
767 		phys = nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[priv->rx_bd_ci],
768 						phys);
769 		netdev_err(ndev, "DMA Rx error 0x%x\n", status);
770 		netdev_err(ndev, "Current BD is at: 0x%llx\n", (u64)phys);
771 
772 		cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
773 		/* Disable coalesce, delay timer and error interrupts */
774 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
775 		/* Finally write to the Tx channel control register */
776 		nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET, cr);
777 
778 		cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
779 		/* Disable coalesce, delay timer and error interrupts */
780 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
781 		/* write to the Rx channel control register */
782 		nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
783 
784 		tasklet_schedule(&priv->dma_err_tasklet);
785 		nixge_dma_write_reg(priv, XAXIDMA_RX_SR_OFFSET, status);
786 	}
787 out:
788 	return IRQ_HANDLED;
789 }
790 
791 static void nixge_dma_err_handler(struct tasklet_struct *t)
792 {
793 	struct nixge_priv *lp = from_tasklet(lp, t, dma_err_tasklet);
794 	struct nixge_hw_dma_bd *cur_p;
795 	struct nixge_tx_skb *tx_skb;
796 	u32 cr, i;
797 
798 	__nixge_device_reset(lp, XAXIDMA_TX_CR_OFFSET);
799 	__nixge_device_reset(lp, XAXIDMA_RX_CR_OFFSET);
800 
801 	for (i = 0; i < TX_BD_NUM; i++) {
802 		cur_p = &lp->tx_bd_v[i];
803 		tx_skb = &lp->tx_skb[i];
804 		nixge_tx_skb_unmap(lp, tx_skb);
805 
806 		nixge_hw_dma_bd_set_phys(cur_p, 0);
807 		cur_p->cntrl = 0;
808 		cur_p->status = 0;
809 		nixge_hw_dma_bd_set_offset(cur_p, 0);
810 	}
811 
812 	for (i = 0; i < RX_BD_NUM; i++) {
813 		cur_p = &lp->rx_bd_v[i];
814 		cur_p->status = 0;
815 	}
816 
817 	lp->tx_bd_ci = 0;
818 	lp->tx_bd_tail = 0;
819 	lp->rx_bd_ci = 0;
820 
821 	/* Start updating the Rx channel control register */
822 	cr = nixge_dma_read_reg(lp, XAXIDMA_RX_CR_OFFSET);
823 	/* Update the interrupt coalesce count */
824 	cr = ((cr & ~XAXIDMA_COALESCE_MASK) |
825 	      (XAXIDMA_DFT_RX_THRESHOLD << XAXIDMA_COALESCE_SHIFT));
826 	/* Update the delay timer count */
827 	cr = ((cr & ~XAXIDMA_DELAY_MASK) |
828 	      (XAXIDMA_DFT_RX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
829 	/* Enable coalesce, delay timer and error interrupts */
830 	cr |= XAXIDMA_IRQ_ALL_MASK;
831 	/* Finally write to the Rx channel control register */
832 	nixge_dma_write_reg(lp, XAXIDMA_RX_CR_OFFSET, cr);
833 
834 	/* Start updating the Tx channel control register */
835 	cr = nixge_dma_read_reg(lp, XAXIDMA_TX_CR_OFFSET);
836 	/* Update the interrupt coalesce count */
837 	cr = (((cr & ~XAXIDMA_COALESCE_MASK)) |
838 	      (XAXIDMA_DFT_TX_THRESHOLD << XAXIDMA_COALESCE_SHIFT));
839 	/* Update the delay timer count */
840 	cr = (((cr & ~XAXIDMA_DELAY_MASK)) |
841 	      (XAXIDMA_DFT_TX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
842 	/* Enable coalesce, delay timer and error interrupts */
843 	cr |= XAXIDMA_IRQ_ALL_MASK;
844 	/* Finally write to the Tx channel control register */
845 	nixge_dma_write_reg(lp, XAXIDMA_TX_CR_OFFSET, cr);
846 
847 	/* Populate the tail pointer and bring the Rx Axi DMA engine out of
848 	 * halted state. This will make the Rx side ready for reception.
849 	 */
850 	nixge_dma_write_desc_reg(lp, XAXIDMA_RX_CDESC_OFFSET, lp->rx_bd_p);
851 	cr = nixge_dma_read_reg(lp, XAXIDMA_RX_CR_OFFSET);
852 	nixge_dma_write_reg(lp, XAXIDMA_RX_CR_OFFSET,
853 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
854 	nixge_dma_write_desc_reg(lp, XAXIDMA_RX_TDESC_OFFSET, lp->rx_bd_p +
855 			    (sizeof(*lp->rx_bd_v) * (RX_BD_NUM - 1)));
856 
857 	/* Write to the RS (Run-stop) bit in the Tx channel control register.
858 	 * Tx channel is now ready to run. But only after we write to the
859 	 * tail pointer register that the Tx channel will start transmitting
860 	 */
861 	nixge_dma_write_desc_reg(lp, XAXIDMA_TX_CDESC_OFFSET, lp->tx_bd_p);
862 	cr = nixge_dma_read_reg(lp, XAXIDMA_TX_CR_OFFSET);
863 	nixge_dma_write_reg(lp, XAXIDMA_TX_CR_OFFSET,
864 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
865 }
866 
867 static int nixge_open(struct net_device *ndev)
868 {
869 	struct nixge_priv *priv = netdev_priv(ndev);
870 	struct phy_device *phy;
871 	int ret;
872 
873 	nixge_device_reset(ndev);
874 
875 	phy = of_phy_connect(ndev, priv->phy_node,
876 			     &nixge_handle_link_change, 0, priv->phy_mode);
877 	if (!phy)
878 		return -ENODEV;
879 
880 	phy_start(phy);
881 
882 	/* Enable tasklets for Axi DMA error handling */
883 	tasklet_setup(&priv->dma_err_tasklet, nixge_dma_err_handler);
884 
885 	napi_enable(&priv->napi);
886 
887 	/* Enable interrupts for Axi DMA Tx */
888 	ret = request_irq(priv->tx_irq, nixge_tx_irq, 0, ndev->name, ndev);
889 	if (ret)
890 		goto err_tx_irq;
891 	/* Enable interrupts for Axi DMA Rx */
892 	ret = request_irq(priv->rx_irq, nixge_rx_irq, 0, ndev->name, ndev);
893 	if (ret)
894 		goto err_rx_irq;
895 
896 	netif_start_queue(ndev);
897 
898 	return 0;
899 
900 err_rx_irq:
901 	free_irq(priv->tx_irq, ndev);
902 err_tx_irq:
903 	phy_stop(phy);
904 	phy_disconnect(phy);
905 	tasklet_kill(&priv->dma_err_tasklet);
906 	netdev_err(ndev, "request_irq() failed\n");
907 	return ret;
908 }
909 
910 static int nixge_stop(struct net_device *ndev)
911 {
912 	struct nixge_priv *priv = netdev_priv(ndev);
913 	u32 cr;
914 
915 	netif_stop_queue(ndev);
916 	napi_disable(&priv->napi);
917 
918 	if (ndev->phydev) {
919 		phy_stop(ndev->phydev);
920 		phy_disconnect(ndev->phydev);
921 	}
922 
923 	cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
924 	nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET,
925 			    cr & (~XAXIDMA_CR_RUNSTOP_MASK));
926 	cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
927 	nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET,
928 			    cr & (~XAXIDMA_CR_RUNSTOP_MASK));
929 
930 	tasklet_kill(&priv->dma_err_tasklet);
931 
932 	free_irq(priv->tx_irq, ndev);
933 	free_irq(priv->rx_irq, ndev);
934 
935 	nixge_hw_dma_bd_release(ndev);
936 
937 	return 0;
938 }
939 
940 static int nixge_change_mtu(struct net_device *ndev, int new_mtu)
941 {
942 	if (netif_running(ndev))
943 		return -EBUSY;
944 
945 	if ((new_mtu + NIXGE_HDR_SIZE + NIXGE_TRL_SIZE) >
946 	     NIXGE_MAX_JUMBO_FRAME_SIZE)
947 		return -EINVAL;
948 
949 	ndev->mtu = new_mtu;
950 
951 	return 0;
952 }
953 
954 static s32 __nixge_hw_set_mac_address(struct net_device *ndev)
955 {
956 	struct nixge_priv *priv = netdev_priv(ndev);
957 
958 	nixge_ctrl_write_reg(priv, NIXGE_REG_MAC_LSB,
959 			     (ndev->dev_addr[2]) << 24 |
960 			     (ndev->dev_addr[3] << 16) |
961 			     (ndev->dev_addr[4] << 8) |
962 			     (ndev->dev_addr[5] << 0));
963 
964 	nixge_ctrl_write_reg(priv, NIXGE_REG_MAC_MSB,
965 			     (ndev->dev_addr[1] | (ndev->dev_addr[0] << 8)));
966 
967 	return 0;
968 }
969 
970 static int nixge_net_set_mac_address(struct net_device *ndev, void *p)
971 {
972 	int err;
973 
974 	err = eth_mac_addr(ndev, p);
975 	if (!err)
976 		__nixge_hw_set_mac_address(ndev);
977 
978 	return err;
979 }
980 
981 static const struct net_device_ops nixge_netdev_ops = {
982 	.ndo_open = nixge_open,
983 	.ndo_stop = nixge_stop,
984 	.ndo_start_xmit = nixge_start_xmit,
985 	.ndo_change_mtu	= nixge_change_mtu,
986 	.ndo_set_mac_address = nixge_net_set_mac_address,
987 	.ndo_validate_addr = eth_validate_addr,
988 };
989 
990 static void nixge_ethtools_get_drvinfo(struct net_device *ndev,
991 				       struct ethtool_drvinfo *ed)
992 {
993 	strscpy(ed->driver, "nixge", sizeof(ed->driver));
994 	strscpy(ed->bus_info, "platform", sizeof(ed->bus_info));
995 }
996 
997 static int
998 nixge_ethtools_get_coalesce(struct net_device *ndev,
999 			    struct ethtool_coalesce *ecoalesce,
1000 			    struct kernel_ethtool_coalesce *kernel_coal,
1001 			    struct netlink_ext_ack *extack)
1002 {
1003 	struct nixge_priv *priv = netdev_priv(ndev);
1004 	u32 regval = 0;
1005 
1006 	regval = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
1007 	ecoalesce->rx_max_coalesced_frames = (regval & XAXIDMA_COALESCE_MASK)
1008 					     >> XAXIDMA_COALESCE_SHIFT;
1009 	regval = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
1010 	ecoalesce->tx_max_coalesced_frames = (regval & XAXIDMA_COALESCE_MASK)
1011 					     >> XAXIDMA_COALESCE_SHIFT;
1012 	return 0;
1013 }
1014 
1015 static int
1016 nixge_ethtools_set_coalesce(struct net_device *ndev,
1017 			    struct ethtool_coalesce *ecoalesce,
1018 			    struct kernel_ethtool_coalesce *kernel_coal,
1019 			    struct netlink_ext_ack *extack)
1020 {
1021 	struct nixge_priv *priv = netdev_priv(ndev);
1022 
1023 	if (netif_running(ndev)) {
1024 		netdev_err(ndev,
1025 			   "Please stop netif before applying configuration\n");
1026 		return -EBUSY;
1027 	}
1028 
1029 	if (ecoalesce->rx_max_coalesced_frames)
1030 		priv->coalesce_count_rx = ecoalesce->rx_max_coalesced_frames;
1031 	if (ecoalesce->tx_max_coalesced_frames)
1032 		priv->coalesce_count_tx = ecoalesce->tx_max_coalesced_frames;
1033 
1034 	return 0;
1035 }
1036 
1037 static int nixge_ethtools_set_phys_id(struct net_device *ndev,
1038 				      enum ethtool_phys_id_state state)
1039 {
1040 	struct nixge_priv *priv = netdev_priv(ndev);
1041 	u32 ctrl;
1042 
1043 	ctrl = nixge_ctrl_read_reg(priv, NIXGE_REG_LED_CTL);
1044 	switch (state) {
1045 	case ETHTOOL_ID_ACTIVE:
1046 		ctrl |= NIXGE_ID_LED_CTL_EN;
1047 		/* Enable identification LED override*/
1048 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1049 		return 2;
1050 
1051 	case ETHTOOL_ID_ON:
1052 		ctrl |= NIXGE_ID_LED_CTL_VAL;
1053 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1054 		break;
1055 
1056 	case ETHTOOL_ID_OFF:
1057 		ctrl &= ~NIXGE_ID_LED_CTL_VAL;
1058 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1059 		break;
1060 
1061 	case ETHTOOL_ID_INACTIVE:
1062 		/* Restore LED settings */
1063 		ctrl &= ~NIXGE_ID_LED_CTL_EN;
1064 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1065 		break;
1066 	}
1067 
1068 	return 0;
1069 }
1070 
1071 static const struct ethtool_ops nixge_ethtool_ops = {
1072 	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES,
1073 	.get_drvinfo    = nixge_ethtools_get_drvinfo,
1074 	.get_coalesce   = nixge_ethtools_get_coalesce,
1075 	.set_coalesce   = nixge_ethtools_set_coalesce,
1076 	.set_phys_id    = nixge_ethtools_set_phys_id,
1077 	.get_link_ksettings     = phy_ethtool_get_link_ksettings,
1078 	.set_link_ksettings     = phy_ethtool_set_link_ksettings,
1079 	.get_link		= ethtool_op_get_link,
1080 };
1081 
1082 static int nixge_mdio_read(struct mii_bus *bus, int phy_id, int reg)
1083 {
1084 	struct nixge_priv *priv = bus->priv;
1085 	u32 status, tmp;
1086 	int err;
1087 	u16 device;
1088 
1089 	if (reg & MII_ADDR_C45) {
1090 		device = (reg >> 16) & 0x1f;
1091 
1092 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_ADDR, reg & 0xffff);
1093 
1094 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_OP_ADDRESS)
1095 			| NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1096 
1097 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1098 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1099 
1100 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1101 					      !status, 10, 1000);
1102 		if (err) {
1103 			dev_err(priv->dev, "timeout setting address");
1104 			return err;
1105 		}
1106 
1107 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_C45_READ) |
1108 			NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1109 	} else {
1110 		device = reg & 0x1f;
1111 
1112 		tmp = NIXGE_MDIO_CLAUSE22 | NIXGE_MDIO_OP(NIXGE_MDIO_C22_READ) |
1113 			NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1114 	}
1115 
1116 	nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1117 	nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1118 
1119 	err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1120 				      !status, 10, 1000);
1121 	if (err) {
1122 		dev_err(priv->dev, "timeout setting read command");
1123 		return err;
1124 	}
1125 
1126 	status = nixge_ctrl_read_reg(priv, NIXGE_REG_MDIO_DATA);
1127 
1128 	return status;
1129 }
1130 
1131 static int nixge_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 val)
1132 {
1133 	struct nixge_priv *priv = bus->priv;
1134 	u32 status, tmp;
1135 	u16 device;
1136 	int err;
1137 
1138 	if (reg & MII_ADDR_C45) {
1139 		device = (reg >> 16) & 0x1f;
1140 
1141 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_ADDR, reg & 0xffff);
1142 
1143 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_OP_ADDRESS)
1144 			| NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1145 
1146 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1147 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1148 
1149 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1150 					      !status, 10, 1000);
1151 		if (err) {
1152 			dev_err(priv->dev, "timeout setting address");
1153 			return err;
1154 		}
1155 
1156 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_C45_WRITE)
1157 			| NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1158 
1159 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_DATA, val);
1160 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1161 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1162 					      !status, 10, 1000);
1163 		if (err)
1164 			dev_err(priv->dev, "timeout setting write command");
1165 	} else {
1166 		device = reg & 0x1f;
1167 
1168 		tmp = NIXGE_MDIO_CLAUSE22 |
1169 			NIXGE_MDIO_OP(NIXGE_MDIO_C22_WRITE) |
1170 			NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1171 
1172 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_DATA, val);
1173 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1174 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1175 
1176 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1177 					      !status, 10, 1000);
1178 		if (err)
1179 			dev_err(priv->dev, "timeout setting write command");
1180 	}
1181 
1182 	return err;
1183 }
1184 
1185 static int nixge_mdio_setup(struct nixge_priv *priv, struct device_node *np)
1186 {
1187 	struct mii_bus *bus;
1188 
1189 	bus = devm_mdiobus_alloc(priv->dev);
1190 	if (!bus)
1191 		return -ENOMEM;
1192 
1193 	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(priv->dev));
1194 	bus->priv = priv;
1195 	bus->name = "nixge_mii_bus";
1196 	bus->read = nixge_mdio_read;
1197 	bus->write = nixge_mdio_write;
1198 	bus->parent = priv->dev;
1199 
1200 	priv->mii_bus = bus;
1201 
1202 	return of_mdiobus_register(bus, np);
1203 }
1204 
1205 static void *nixge_get_nvmem_address(struct device *dev)
1206 {
1207 	struct nvmem_cell *cell;
1208 	size_t cell_size;
1209 	char *mac;
1210 
1211 	cell = nvmem_cell_get(dev, "address");
1212 	if (IS_ERR(cell))
1213 		return cell;
1214 
1215 	mac = nvmem_cell_read(cell, &cell_size);
1216 	nvmem_cell_put(cell);
1217 
1218 	return mac;
1219 }
1220 
1221 /* Match table for of_platform binding */
1222 static const struct of_device_id nixge_dt_ids[] = {
1223 	{ .compatible = "ni,xge-enet-2.00", .data = (void *)NIXGE_V2 },
1224 	{ .compatible = "ni,xge-enet-3.00", .data = (void *)NIXGE_V3 },
1225 	{},
1226 };
1227 MODULE_DEVICE_TABLE(of, nixge_dt_ids);
1228 
1229 static int nixge_of_get_resources(struct platform_device *pdev)
1230 {
1231 	const struct of_device_id *of_id;
1232 	enum nixge_version version;
1233 	struct net_device *ndev;
1234 	struct nixge_priv *priv;
1235 
1236 	ndev = platform_get_drvdata(pdev);
1237 	priv = netdev_priv(ndev);
1238 	of_id = of_match_node(nixge_dt_ids, pdev->dev.of_node);
1239 	if (!of_id)
1240 		return -ENODEV;
1241 
1242 	version = (enum nixge_version)of_id->data;
1243 	if (version <= NIXGE_V2)
1244 		priv->dma_regs = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
1245 	else
1246 		priv->dma_regs = devm_platform_ioremap_resource_byname(pdev, "dma");
1247 	if (IS_ERR(priv->dma_regs)) {
1248 		netdev_err(ndev, "failed to map dma regs\n");
1249 		return PTR_ERR(priv->dma_regs);
1250 	}
1251 	if (version <= NIXGE_V2)
1252 		priv->ctrl_regs = priv->dma_regs + NIXGE_REG_CTRL_OFFSET;
1253 	else
1254 		priv->ctrl_regs = devm_platform_ioremap_resource_byname(pdev, "ctrl");
1255 	if (IS_ERR(priv->ctrl_regs)) {
1256 		netdev_err(ndev, "failed to map ctrl regs\n");
1257 		return PTR_ERR(priv->ctrl_regs);
1258 	}
1259 	return 0;
1260 }
1261 
1262 static int nixge_probe(struct platform_device *pdev)
1263 {
1264 	struct device_node *mn, *phy_node;
1265 	struct nixge_priv *priv;
1266 	struct net_device *ndev;
1267 	const u8 *mac_addr;
1268 	int err;
1269 
1270 	ndev = alloc_etherdev(sizeof(*priv));
1271 	if (!ndev)
1272 		return -ENOMEM;
1273 
1274 	platform_set_drvdata(pdev, ndev);
1275 	SET_NETDEV_DEV(ndev, &pdev->dev);
1276 
1277 	ndev->features = NETIF_F_SG;
1278 	ndev->netdev_ops = &nixge_netdev_ops;
1279 	ndev->ethtool_ops = &nixge_ethtool_ops;
1280 
1281 	/* MTU range: 64 - 9000 */
1282 	ndev->min_mtu = 64;
1283 	ndev->max_mtu = NIXGE_JUMBO_MTU;
1284 
1285 	mac_addr = nixge_get_nvmem_address(&pdev->dev);
1286 	if (!IS_ERR(mac_addr) && is_valid_ether_addr(mac_addr)) {
1287 		eth_hw_addr_set(ndev, mac_addr);
1288 		kfree(mac_addr);
1289 	} else {
1290 		eth_hw_addr_random(ndev);
1291 	}
1292 
1293 	priv = netdev_priv(ndev);
1294 	priv->ndev = ndev;
1295 	priv->dev = &pdev->dev;
1296 
1297 	netif_napi_add(ndev, &priv->napi, nixge_poll);
1298 	err = nixge_of_get_resources(pdev);
1299 	if (err)
1300 		goto free_netdev;
1301 	__nixge_hw_set_mac_address(ndev);
1302 
1303 	priv->tx_irq = platform_get_irq_byname(pdev, "tx");
1304 	if (priv->tx_irq < 0) {
1305 		netdev_err(ndev, "could not find 'tx' irq");
1306 		err = priv->tx_irq;
1307 		goto free_netdev;
1308 	}
1309 
1310 	priv->rx_irq = platform_get_irq_byname(pdev, "rx");
1311 	if (priv->rx_irq < 0) {
1312 		netdev_err(ndev, "could not find 'rx' irq");
1313 		err = priv->rx_irq;
1314 		goto free_netdev;
1315 	}
1316 
1317 	priv->coalesce_count_rx = XAXIDMA_DFT_RX_THRESHOLD;
1318 	priv->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD;
1319 
1320 	mn = of_get_child_by_name(pdev->dev.of_node, "mdio");
1321 	if (mn) {
1322 		err = nixge_mdio_setup(priv, mn);
1323 		of_node_put(mn);
1324 		if (err) {
1325 			netdev_err(ndev, "error registering mdio bus");
1326 			goto free_netdev;
1327 		}
1328 	}
1329 
1330 	err = of_get_phy_mode(pdev->dev.of_node, &priv->phy_mode);
1331 	if (err) {
1332 		netdev_err(ndev, "not find \"phy-mode\" property\n");
1333 		goto unregister_mdio;
1334 	}
1335 
1336 	phy_node = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
1337 	if (!phy_node && of_phy_is_fixed_link(pdev->dev.of_node)) {
1338 		err = of_phy_register_fixed_link(pdev->dev.of_node);
1339 		if (err < 0) {
1340 			netdev_err(ndev, "broken fixed-link specification\n");
1341 			goto unregister_mdio;
1342 		}
1343 		phy_node = of_node_get(pdev->dev.of_node);
1344 	}
1345 	priv->phy_node = phy_node;
1346 
1347 	err = register_netdev(priv->ndev);
1348 	if (err) {
1349 		netdev_err(ndev, "register_netdev() error (%i)\n", err);
1350 		goto free_phy;
1351 	}
1352 
1353 	return 0;
1354 
1355 free_phy:
1356 	if (of_phy_is_fixed_link(pdev->dev.of_node))
1357 		of_phy_deregister_fixed_link(pdev->dev.of_node);
1358 	of_node_put(phy_node);
1359 
1360 unregister_mdio:
1361 	if (priv->mii_bus)
1362 		mdiobus_unregister(priv->mii_bus);
1363 
1364 free_netdev:
1365 	free_netdev(ndev);
1366 
1367 	return err;
1368 }
1369 
1370 static int nixge_remove(struct platform_device *pdev)
1371 {
1372 	struct net_device *ndev = platform_get_drvdata(pdev);
1373 	struct nixge_priv *priv = netdev_priv(ndev);
1374 
1375 	unregister_netdev(ndev);
1376 
1377 	if (of_phy_is_fixed_link(pdev->dev.of_node))
1378 		of_phy_deregister_fixed_link(pdev->dev.of_node);
1379 	of_node_put(priv->phy_node);
1380 
1381 	if (priv->mii_bus)
1382 		mdiobus_unregister(priv->mii_bus);
1383 
1384 	free_netdev(ndev);
1385 
1386 	return 0;
1387 }
1388 
1389 static struct platform_driver nixge_driver = {
1390 	.probe		= nixge_probe,
1391 	.remove		= nixge_remove,
1392 	.driver		= {
1393 		.name		= "nixge",
1394 		.of_match_table	= of_match_ptr(nixge_dt_ids),
1395 	},
1396 };
1397 module_platform_driver(nixge_driver);
1398 
1399 MODULE_LICENSE("GPL v2");
1400 MODULE_DESCRIPTION("National Instruments XGE Management MAC");
1401 MODULE_AUTHOR("Moritz Fischer <mdf@kernel.org>");
1402