xref: /openbmc/linux/drivers/net/ethernet/ni/nixge.c (revision 3e50b639)
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 	if (priv->rx_bd_v) {
253 		for (i = 0; i < RX_BD_NUM; i++) {
254 			phys_addr = nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
255 							     phys);
256 
257 			dma_unmap_single(ndev->dev.parent, phys_addr,
258 					 NIXGE_MAX_JUMBO_FRAME_SIZE,
259 					 DMA_FROM_DEVICE);
260 
261 			skb = (struct sk_buff *)(uintptr_t)
262 				nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
263 							 sw_id_offset);
264 			dev_kfree_skb(skb);
265 		}
266 
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 
273 	if (priv->tx_skb)
274 		devm_kfree(ndev->dev.parent, priv->tx_skb);
275 
276 	if (priv->tx_bd_v)
277 		dma_free_coherent(ndev->dev.parent,
278 				  sizeof(*priv->tx_bd_v) * TX_BD_NUM,
279 				  priv->tx_bd_v,
280 				  priv->tx_bd_p);
281 }
282 
283 static int nixge_hw_dma_bd_init(struct net_device *ndev)
284 {
285 	struct nixge_priv *priv = netdev_priv(ndev);
286 	struct sk_buff *skb;
287 	dma_addr_t phys;
288 	u32 cr;
289 	int i;
290 
291 	/* Reset the indexes which are used for accessing the BDs */
292 	priv->tx_bd_ci = 0;
293 	priv->tx_bd_tail = 0;
294 	priv->rx_bd_ci = 0;
295 
296 	/* Allocate the Tx and Rx buffer descriptors. */
297 	priv->tx_bd_v = dma_alloc_coherent(ndev->dev.parent,
298 					   sizeof(*priv->tx_bd_v) * TX_BD_NUM,
299 					   &priv->tx_bd_p, GFP_KERNEL);
300 	if (!priv->tx_bd_v)
301 		goto out;
302 
303 	priv->tx_skb = devm_kcalloc(ndev->dev.parent,
304 				    TX_BD_NUM, sizeof(*priv->tx_skb),
305 				    GFP_KERNEL);
306 	if (!priv->tx_skb)
307 		goto out;
308 
309 	priv->rx_bd_v = dma_alloc_coherent(ndev->dev.parent,
310 					   sizeof(*priv->rx_bd_v) * RX_BD_NUM,
311 					   &priv->rx_bd_p, GFP_KERNEL);
312 	if (!priv->rx_bd_v)
313 		goto out;
314 
315 	for (i = 0; i < TX_BD_NUM; i++) {
316 		nixge_hw_dma_bd_set_next(&priv->tx_bd_v[i],
317 					 priv->tx_bd_p +
318 					 sizeof(*priv->tx_bd_v) *
319 					 ((i + 1) % TX_BD_NUM));
320 	}
321 
322 	for (i = 0; i < RX_BD_NUM; i++) {
323 		nixge_hw_dma_bd_set_next(&priv->rx_bd_v[i],
324 					 priv->rx_bd_p
325 					 + sizeof(*priv->rx_bd_v) *
326 					 ((i + 1) % RX_BD_NUM));
327 
328 		skb = __netdev_alloc_skb_ip_align(ndev,
329 						  NIXGE_MAX_JUMBO_FRAME_SIZE,
330 						  GFP_KERNEL);
331 		if (!skb)
332 			goto out;
333 
334 		nixge_hw_dma_bd_set_offset(&priv->rx_bd_v[i], (uintptr_t)skb);
335 		phys = dma_map_single(ndev->dev.parent, skb->data,
336 				      NIXGE_MAX_JUMBO_FRAME_SIZE,
337 				      DMA_FROM_DEVICE);
338 
339 		nixge_hw_dma_bd_set_phys(&priv->rx_bd_v[i], phys);
340 
341 		priv->rx_bd_v[i].cntrl = NIXGE_MAX_JUMBO_FRAME_SIZE;
342 	}
343 
344 	/* Start updating the Rx channel control register */
345 	cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
346 	/* Update the interrupt coalesce count */
347 	cr = ((cr & ~XAXIDMA_COALESCE_MASK) |
348 	      ((priv->coalesce_count_rx) << XAXIDMA_COALESCE_SHIFT));
349 	/* Update the delay timer count */
350 	cr = ((cr & ~XAXIDMA_DELAY_MASK) |
351 	      (XAXIDMA_DFT_RX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
352 	/* Enable coalesce, delay timer and error interrupts */
353 	cr |= XAXIDMA_IRQ_ALL_MASK;
354 	/* Write to the Rx channel control register */
355 	nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
356 
357 	/* Start updating the Tx channel control register */
358 	cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
359 	/* Update the interrupt coalesce count */
360 	cr = (((cr & ~XAXIDMA_COALESCE_MASK)) |
361 	      ((priv->coalesce_count_tx) << XAXIDMA_COALESCE_SHIFT));
362 	/* Update the delay timer count */
363 	cr = (((cr & ~XAXIDMA_DELAY_MASK)) |
364 	      (XAXIDMA_DFT_TX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
365 	/* Enable coalesce, delay timer and error interrupts */
366 	cr |= XAXIDMA_IRQ_ALL_MASK;
367 	/* Write to the Tx channel control register */
368 	nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET, cr);
369 
370 	/* Populate the tail pointer and bring the Rx Axi DMA engine out of
371 	 * halted state. This will make the Rx side ready for reception.
372 	 */
373 	nixge_dma_write_desc_reg(priv, XAXIDMA_RX_CDESC_OFFSET, priv->rx_bd_p);
374 	cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
375 	nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET,
376 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
377 	nixge_dma_write_desc_reg(priv, XAXIDMA_RX_TDESC_OFFSET, priv->rx_bd_p +
378 			    (sizeof(*priv->rx_bd_v) * (RX_BD_NUM - 1)));
379 
380 	/* Write to the RS (Run-stop) bit in the Tx channel control register.
381 	 * Tx channel is now ready to run. But only after we write to the
382 	 * tail pointer register that the Tx channel will start transmitting.
383 	 */
384 	nixge_dma_write_desc_reg(priv, XAXIDMA_TX_CDESC_OFFSET, priv->tx_bd_p);
385 	cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
386 	nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET,
387 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
388 
389 	return 0;
390 out:
391 	nixge_hw_dma_bd_release(ndev);
392 	return -ENOMEM;
393 }
394 
395 static void __nixge_device_reset(struct nixge_priv *priv, off_t offset)
396 {
397 	u32 status;
398 	int err;
399 
400 	/* Reset Axi DMA. This would reset NIXGE Ethernet core as well.
401 	 * The reset process of Axi DMA takes a while to complete as all
402 	 * pending commands/transfers will be flushed or completed during
403 	 * this reset process.
404 	 */
405 	nixge_dma_write_reg(priv, offset, XAXIDMA_CR_RESET_MASK);
406 	err = nixge_dma_poll_timeout(priv, offset, status,
407 				     !(status & XAXIDMA_CR_RESET_MASK), 10,
408 				     1000);
409 	if (err)
410 		netdev_err(priv->ndev, "%s: DMA reset timeout!\n", __func__);
411 }
412 
413 static void nixge_device_reset(struct net_device *ndev)
414 {
415 	struct nixge_priv *priv = netdev_priv(ndev);
416 
417 	__nixge_device_reset(priv, XAXIDMA_TX_CR_OFFSET);
418 	__nixge_device_reset(priv, XAXIDMA_RX_CR_OFFSET);
419 
420 	if (nixge_hw_dma_bd_init(ndev))
421 		netdev_err(ndev, "%s: descriptor allocation failed\n",
422 			   __func__);
423 
424 	netif_trans_update(ndev);
425 }
426 
427 static void nixge_handle_link_change(struct net_device *ndev)
428 {
429 	struct nixge_priv *priv = netdev_priv(ndev);
430 	struct phy_device *phydev = ndev->phydev;
431 
432 	if (phydev->link != priv->link || phydev->speed != priv->speed ||
433 	    phydev->duplex != priv->duplex) {
434 		priv->link = phydev->link;
435 		priv->speed = phydev->speed;
436 		priv->duplex = phydev->duplex;
437 		phy_print_status(phydev);
438 	}
439 }
440 
441 static void nixge_tx_skb_unmap(struct nixge_priv *priv,
442 			       struct nixge_tx_skb *tx_skb)
443 {
444 	if (tx_skb->mapping) {
445 		if (tx_skb->mapped_as_page)
446 			dma_unmap_page(priv->ndev->dev.parent, tx_skb->mapping,
447 				       tx_skb->size, DMA_TO_DEVICE);
448 		else
449 			dma_unmap_single(priv->ndev->dev.parent,
450 					 tx_skb->mapping,
451 					 tx_skb->size, DMA_TO_DEVICE);
452 		tx_skb->mapping = 0;
453 	}
454 
455 	if (tx_skb->skb) {
456 		dev_kfree_skb_any(tx_skb->skb);
457 		tx_skb->skb = NULL;
458 	}
459 }
460 
461 static void nixge_start_xmit_done(struct net_device *ndev)
462 {
463 	struct nixge_priv *priv = netdev_priv(ndev);
464 	struct nixge_hw_dma_bd *cur_p;
465 	struct nixge_tx_skb *tx_skb;
466 	unsigned int status = 0;
467 	u32 packets = 0;
468 	u32 size = 0;
469 
470 	cur_p = &priv->tx_bd_v[priv->tx_bd_ci];
471 	tx_skb = &priv->tx_skb[priv->tx_bd_ci];
472 
473 	status = cur_p->status;
474 
475 	while (status & XAXIDMA_BD_STS_COMPLETE_MASK) {
476 		nixge_tx_skb_unmap(priv, tx_skb);
477 		cur_p->status = 0;
478 
479 		size += status & XAXIDMA_BD_STS_ACTUAL_LEN_MASK;
480 		packets++;
481 
482 		++priv->tx_bd_ci;
483 		priv->tx_bd_ci %= TX_BD_NUM;
484 		cur_p = &priv->tx_bd_v[priv->tx_bd_ci];
485 		tx_skb = &priv->tx_skb[priv->tx_bd_ci];
486 		status = cur_p->status;
487 	}
488 
489 	ndev->stats.tx_packets += packets;
490 	ndev->stats.tx_bytes += size;
491 
492 	if (packets)
493 		netif_wake_queue(ndev);
494 }
495 
496 static int nixge_check_tx_bd_space(struct nixge_priv *priv,
497 				   int num_frag)
498 {
499 	struct nixge_hw_dma_bd *cur_p;
500 
501 	cur_p = &priv->tx_bd_v[(priv->tx_bd_tail + num_frag) % TX_BD_NUM];
502 	if (cur_p->status & XAXIDMA_BD_STS_ALL_MASK)
503 		return NETDEV_TX_BUSY;
504 	return 0;
505 }
506 
507 static netdev_tx_t nixge_start_xmit(struct sk_buff *skb,
508 				    struct net_device *ndev)
509 {
510 	struct nixge_priv *priv = netdev_priv(ndev);
511 	struct nixge_hw_dma_bd *cur_p;
512 	struct nixge_tx_skb *tx_skb;
513 	dma_addr_t tail_p, cur_phys;
514 	skb_frag_t *frag;
515 	u32 num_frag;
516 	u32 ii;
517 
518 	num_frag = skb_shinfo(skb)->nr_frags;
519 	cur_p = &priv->tx_bd_v[priv->tx_bd_tail];
520 	tx_skb = &priv->tx_skb[priv->tx_bd_tail];
521 
522 	if (nixge_check_tx_bd_space(priv, num_frag)) {
523 		if (!netif_queue_stopped(ndev))
524 			netif_stop_queue(ndev);
525 		return NETDEV_TX_OK;
526 	}
527 
528 	cur_phys = dma_map_single(ndev->dev.parent, skb->data,
529 				  skb_headlen(skb), DMA_TO_DEVICE);
530 	if (dma_mapping_error(ndev->dev.parent, cur_phys))
531 		goto drop;
532 	nixge_hw_dma_bd_set_phys(cur_p, cur_phys);
533 
534 	cur_p->cntrl = skb_headlen(skb) | XAXIDMA_BD_CTRL_TXSOF_MASK;
535 
536 	tx_skb->skb = NULL;
537 	tx_skb->mapping = cur_phys;
538 	tx_skb->size = skb_headlen(skb);
539 	tx_skb->mapped_as_page = false;
540 
541 	for (ii = 0; ii < num_frag; ii++) {
542 		++priv->tx_bd_tail;
543 		priv->tx_bd_tail %= TX_BD_NUM;
544 		cur_p = &priv->tx_bd_v[priv->tx_bd_tail];
545 		tx_skb = &priv->tx_skb[priv->tx_bd_tail];
546 		frag = &skb_shinfo(skb)->frags[ii];
547 
548 		cur_phys = skb_frag_dma_map(ndev->dev.parent, frag, 0,
549 					    skb_frag_size(frag),
550 					    DMA_TO_DEVICE);
551 		if (dma_mapping_error(ndev->dev.parent, cur_phys))
552 			goto frag_err;
553 		nixge_hw_dma_bd_set_phys(cur_p, cur_phys);
554 
555 		cur_p->cntrl = skb_frag_size(frag);
556 
557 		tx_skb->skb = NULL;
558 		tx_skb->mapping = cur_phys;
559 		tx_skb->size = skb_frag_size(frag);
560 		tx_skb->mapped_as_page = true;
561 	}
562 
563 	/* last buffer of the frame */
564 	tx_skb->skb = skb;
565 
566 	cur_p->cntrl |= XAXIDMA_BD_CTRL_TXEOF_MASK;
567 
568 	tail_p = priv->tx_bd_p + sizeof(*priv->tx_bd_v) * priv->tx_bd_tail;
569 	/* Start the transfer */
570 	nixge_dma_write_desc_reg(priv, XAXIDMA_TX_TDESC_OFFSET, tail_p);
571 	++priv->tx_bd_tail;
572 	priv->tx_bd_tail %= TX_BD_NUM;
573 
574 	return NETDEV_TX_OK;
575 frag_err:
576 	for (; ii > 0; ii--) {
577 		if (priv->tx_bd_tail)
578 			priv->tx_bd_tail--;
579 		else
580 			priv->tx_bd_tail = TX_BD_NUM - 1;
581 
582 		tx_skb = &priv->tx_skb[priv->tx_bd_tail];
583 		nixge_tx_skb_unmap(priv, tx_skb);
584 
585 		cur_p = &priv->tx_bd_v[priv->tx_bd_tail];
586 		cur_p->status = 0;
587 	}
588 	dma_unmap_single(priv->ndev->dev.parent,
589 			 tx_skb->mapping,
590 			 tx_skb->size, DMA_TO_DEVICE);
591 drop:
592 	ndev->stats.tx_dropped++;
593 	return NETDEV_TX_OK;
594 }
595 
596 static int nixge_recv(struct net_device *ndev, int budget)
597 {
598 	struct nixge_priv *priv = netdev_priv(ndev);
599 	struct sk_buff *skb, *new_skb;
600 	struct nixge_hw_dma_bd *cur_p;
601 	dma_addr_t tail_p = 0, cur_phys = 0;
602 	u32 packets = 0;
603 	u32 length = 0;
604 	u32 size = 0;
605 
606 	cur_p = &priv->rx_bd_v[priv->rx_bd_ci];
607 
608 	while ((cur_p->status & XAXIDMA_BD_STS_COMPLETE_MASK &&
609 		budget > packets)) {
610 		tail_p = priv->rx_bd_p + sizeof(*priv->rx_bd_v) *
611 			 priv->rx_bd_ci;
612 
613 		skb = (struct sk_buff *)(uintptr_t)
614 			nixge_hw_dma_bd_get_addr(cur_p, sw_id_offset);
615 
616 		length = cur_p->status & XAXIDMA_BD_STS_ACTUAL_LEN_MASK;
617 		if (length > NIXGE_MAX_JUMBO_FRAME_SIZE)
618 			length = NIXGE_MAX_JUMBO_FRAME_SIZE;
619 
620 		dma_unmap_single(ndev->dev.parent,
621 				 nixge_hw_dma_bd_get_addr(cur_p, phys),
622 				 NIXGE_MAX_JUMBO_FRAME_SIZE,
623 				 DMA_FROM_DEVICE);
624 
625 		skb_put(skb, length);
626 
627 		skb->protocol = eth_type_trans(skb, ndev);
628 		skb_checksum_none_assert(skb);
629 
630 		/* For now mark them as CHECKSUM_NONE since
631 		 * we don't have offload capabilities
632 		 */
633 		skb->ip_summed = CHECKSUM_NONE;
634 
635 		napi_gro_receive(&priv->napi, skb);
636 
637 		size += length;
638 		packets++;
639 
640 		new_skb = netdev_alloc_skb_ip_align(ndev,
641 						    NIXGE_MAX_JUMBO_FRAME_SIZE);
642 		if (!new_skb)
643 			return packets;
644 
645 		cur_phys = dma_map_single(ndev->dev.parent, new_skb->data,
646 					  NIXGE_MAX_JUMBO_FRAME_SIZE,
647 					  DMA_FROM_DEVICE);
648 		if (dma_mapping_error(ndev->dev.parent, cur_phys)) {
649 			/* FIXME: bail out and clean up */
650 			netdev_err(ndev, "Failed to map ...\n");
651 		}
652 		nixge_hw_dma_bd_set_phys(cur_p, cur_phys);
653 		cur_p->cntrl = NIXGE_MAX_JUMBO_FRAME_SIZE;
654 		cur_p->status = 0;
655 		nixge_hw_dma_bd_set_offset(cur_p, (uintptr_t)new_skb);
656 
657 		++priv->rx_bd_ci;
658 		priv->rx_bd_ci %= RX_BD_NUM;
659 		cur_p = &priv->rx_bd_v[priv->rx_bd_ci];
660 	}
661 
662 	ndev->stats.rx_packets += packets;
663 	ndev->stats.rx_bytes += size;
664 
665 	if (tail_p)
666 		nixge_dma_write_desc_reg(priv, XAXIDMA_RX_TDESC_OFFSET, tail_p);
667 
668 	return packets;
669 }
670 
671 static int nixge_poll(struct napi_struct *napi, int budget)
672 {
673 	struct nixge_priv *priv = container_of(napi, struct nixge_priv, napi);
674 	int work_done;
675 	u32 status, cr;
676 
677 	work_done = 0;
678 
679 	work_done = nixge_recv(priv->ndev, budget);
680 	if (work_done < budget) {
681 		napi_complete_done(napi, work_done);
682 		status = nixge_dma_read_reg(priv, XAXIDMA_RX_SR_OFFSET);
683 
684 		if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
685 			/* If there's more, reschedule, but clear */
686 			nixge_dma_write_reg(priv, XAXIDMA_RX_SR_OFFSET, status);
687 			napi_reschedule(napi);
688 		} else {
689 			/* if not, turn on RX IRQs again ... */
690 			cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
691 			cr |= (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK);
692 			nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
693 		}
694 	}
695 
696 	return work_done;
697 }
698 
699 static irqreturn_t nixge_tx_irq(int irq, void *_ndev)
700 {
701 	struct nixge_priv *priv = netdev_priv(_ndev);
702 	struct net_device *ndev = _ndev;
703 	unsigned int status;
704 	dma_addr_t phys;
705 	u32 cr;
706 
707 	status = nixge_dma_read_reg(priv, XAXIDMA_TX_SR_OFFSET);
708 	if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
709 		nixge_dma_write_reg(priv, XAXIDMA_TX_SR_OFFSET, status);
710 		nixge_start_xmit_done(priv->ndev);
711 		goto out;
712 	}
713 	if (!(status & XAXIDMA_IRQ_ALL_MASK)) {
714 		netdev_err(ndev, "No interrupts asserted in Tx path\n");
715 		return IRQ_NONE;
716 	}
717 	if (status & XAXIDMA_IRQ_ERROR_MASK) {
718 		phys = nixge_hw_dma_bd_get_addr(&priv->tx_bd_v[priv->tx_bd_ci],
719 						phys);
720 
721 		netdev_err(ndev, "DMA Tx error 0x%x\n", status);
722 		netdev_err(ndev, "Current BD is at: 0x%llx\n", (u64)phys);
723 
724 		cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
725 		/* Disable coalesce, delay timer and error interrupts */
726 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
727 		/* Write to the Tx channel control register */
728 		nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET, cr);
729 
730 		cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
731 		/* Disable coalesce, delay timer and error interrupts */
732 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
733 		/* Write to the Rx channel control register */
734 		nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
735 
736 		tasklet_schedule(&priv->dma_err_tasklet);
737 		nixge_dma_write_reg(priv, XAXIDMA_TX_SR_OFFSET, status);
738 	}
739 out:
740 	return IRQ_HANDLED;
741 }
742 
743 static irqreturn_t nixge_rx_irq(int irq, void *_ndev)
744 {
745 	struct nixge_priv *priv = netdev_priv(_ndev);
746 	struct net_device *ndev = _ndev;
747 	unsigned int status;
748 	dma_addr_t phys;
749 	u32 cr;
750 
751 	status = nixge_dma_read_reg(priv, XAXIDMA_RX_SR_OFFSET);
752 	if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
753 		/* Turn of IRQs because NAPI */
754 		nixge_dma_write_reg(priv, XAXIDMA_RX_SR_OFFSET, status);
755 		cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
756 		cr &= ~(XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK);
757 		nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
758 
759 		if (napi_schedule_prep(&priv->napi))
760 			__napi_schedule(&priv->napi);
761 		goto out;
762 	}
763 	if (!(status & XAXIDMA_IRQ_ALL_MASK)) {
764 		netdev_err(ndev, "No interrupts asserted in Rx path\n");
765 		return IRQ_NONE;
766 	}
767 	if (status & XAXIDMA_IRQ_ERROR_MASK) {
768 		phys = nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[priv->rx_bd_ci],
769 						phys);
770 		netdev_err(ndev, "DMA Rx error 0x%x\n", status);
771 		netdev_err(ndev, "Current BD is at: 0x%llx\n", (u64)phys);
772 
773 		cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
774 		/* Disable coalesce, delay timer and error interrupts */
775 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
776 		/* Finally write to the Tx channel control register */
777 		nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET, cr);
778 
779 		cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
780 		/* Disable coalesce, delay timer and error interrupts */
781 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
782 		/* write to the Rx channel control register */
783 		nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET, cr);
784 
785 		tasklet_schedule(&priv->dma_err_tasklet);
786 		nixge_dma_write_reg(priv, XAXIDMA_RX_SR_OFFSET, status);
787 	}
788 out:
789 	return IRQ_HANDLED;
790 }
791 
792 static void nixge_dma_err_handler(struct tasklet_struct *t)
793 {
794 	struct nixge_priv *lp = from_tasklet(lp, t, dma_err_tasklet);
795 	struct nixge_hw_dma_bd *cur_p;
796 	struct nixge_tx_skb *tx_skb;
797 	u32 cr, i;
798 
799 	__nixge_device_reset(lp, XAXIDMA_TX_CR_OFFSET);
800 	__nixge_device_reset(lp, XAXIDMA_RX_CR_OFFSET);
801 
802 	for (i = 0; i < TX_BD_NUM; i++) {
803 		cur_p = &lp->tx_bd_v[i];
804 		tx_skb = &lp->tx_skb[i];
805 		nixge_tx_skb_unmap(lp, tx_skb);
806 
807 		nixge_hw_dma_bd_set_phys(cur_p, 0);
808 		cur_p->cntrl = 0;
809 		cur_p->status = 0;
810 		nixge_hw_dma_bd_set_offset(cur_p, 0);
811 	}
812 
813 	for (i = 0; i < RX_BD_NUM; i++) {
814 		cur_p = &lp->rx_bd_v[i];
815 		cur_p->status = 0;
816 	}
817 
818 	lp->tx_bd_ci = 0;
819 	lp->tx_bd_tail = 0;
820 	lp->rx_bd_ci = 0;
821 
822 	/* Start updating the Rx channel control register */
823 	cr = nixge_dma_read_reg(lp, XAXIDMA_RX_CR_OFFSET);
824 	/* Update the interrupt coalesce count */
825 	cr = ((cr & ~XAXIDMA_COALESCE_MASK) |
826 	      (XAXIDMA_DFT_RX_THRESHOLD << XAXIDMA_COALESCE_SHIFT));
827 	/* Update the delay timer count */
828 	cr = ((cr & ~XAXIDMA_DELAY_MASK) |
829 	      (XAXIDMA_DFT_RX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
830 	/* Enable coalesce, delay timer and error interrupts */
831 	cr |= XAXIDMA_IRQ_ALL_MASK;
832 	/* Finally write to the Rx channel control register */
833 	nixge_dma_write_reg(lp, XAXIDMA_RX_CR_OFFSET, cr);
834 
835 	/* Start updating the Tx channel control register */
836 	cr = nixge_dma_read_reg(lp, XAXIDMA_TX_CR_OFFSET);
837 	/* Update the interrupt coalesce count */
838 	cr = (((cr & ~XAXIDMA_COALESCE_MASK)) |
839 	      (XAXIDMA_DFT_TX_THRESHOLD << XAXIDMA_COALESCE_SHIFT));
840 	/* Update the delay timer count */
841 	cr = (((cr & ~XAXIDMA_DELAY_MASK)) |
842 	      (XAXIDMA_DFT_TX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
843 	/* Enable coalesce, delay timer and error interrupts */
844 	cr |= XAXIDMA_IRQ_ALL_MASK;
845 	/* Finally write to the Tx channel control register */
846 	nixge_dma_write_reg(lp, XAXIDMA_TX_CR_OFFSET, cr);
847 
848 	/* Populate the tail pointer and bring the Rx Axi DMA engine out of
849 	 * halted state. This will make the Rx side ready for reception.
850 	 */
851 	nixge_dma_write_desc_reg(lp, XAXIDMA_RX_CDESC_OFFSET, lp->rx_bd_p);
852 	cr = nixge_dma_read_reg(lp, XAXIDMA_RX_CR_OFFSET);
853 	nixge_dma_write_reg(lp, XAXIDMA_RX_CR_OFFSET,
854 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
855 	nixge_dma_write_desc_reg(lp, XAXIDMA_RX_TDESC_OFFSET, lp->rx_bd_p +
856 			    (sizeof(*lp->rx_bd_v) * (RX_BD_NUM - 1)));
857 
858 	/* Write to the RS (Run-stop) bit in the Tx channel control register.
859 	 * Tx channel is now ready to run. But only after we write to the
860 	 * tail pointer register that the Tx channel will start transmitting
861 	 */
862 	nixge_dma_write_desc_reg(lp, XAXIDMA_TX_CDESC_OFFSET, lp->tx_bd_p);
863 	cr = nixge_dma_read_reg(lp, XAXIDMA_TX_CR_OFFSET);
864 	nixge_dma_write_reg(lp, XAXIDMA_TX_CR_OFFSET,
865 			    cr | XAXIDMA_CR_RUNSTOP_MASK);
866 }
867 
868 static int nixge_open(struct net_device *ndev)
869 {
870 	struct nixge_priv *priv = netdev_priv(ndev);
871 	struct phy_device *phy;
872 	int ret;
873 
874 	nixge_device_reset(ndev);
875 
876 	phy = of_phy_connect(ndev, priv->phy_node,
877 			     &nixge_handle_link_change, 0, priv->phy_mode);
878 	if (!phy)
879 		return -ENODEV;
880 
881 	phy_start(phy);
882 
883 	/* Enable tasklets for Axi DMA error handling */
884 	tasklet_setup(&priv->dma_err_tasklet, nixge_dma_err_handler);
885 
886 	napi_enable(&priv->napi);
887 
888 	/* Enable interrupts for Axi DMA Tx */
889 	ret = request_irq(priv->tx_irq, nixge_tx_irq, 0, ndev->name, ndev);
890 	if (ret)
891 		goto err_tx_irq;
892 	/* Enable interrupts for Axi DMA Rx */
893 	ret = request_irq(priv->rx_irq, nixge_rx_irq, 0, ndev->name, ndev);
894 	if (ret)
895 		goto err_rx_irq;
896 
897 	netif_start_queue(ndev);
898 
899 	return 0;
900 
901 err_rx_irq:
902 	free_irq(priv->tx_irq, ndev);
903 err_tx_irq:
904 	napi_disable(&priv->napi);
905 	phy_stop(phy);
906 	phy_disconnect(phy);
907 	tasklet_kill(&priv->dma_err_tasklet);
908 	netdev_err(ndev, "request_irq() failed\n");
909 	return ret;
910 }
911 
912 static int nixge_stop(struct net_device *ndev)
913 {
914 	struct nixge_priv *priv = netdev_priv(ndev);
915 	u32 cr;
916 
917 	netif_stop_queue(ndev);
918 	napi_disable(&priv->napi);
919 
920 	if (ndev->phydev) {
921 		phy_stop(ndev->phydev);
922 		phy_disconnect(ndev->phydev);
923 	}
924 
925 	cr = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
926 	nixge_dma_write_reg(priv, XAXIDMA_RX_CR_OFFSET,
927 			    cr & (~XAXIDMA_CR_RUNSTOP_MASK));
928 	cr = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
929 	nixge_dma_write_reg(priv, XAXIDMA_TX_CR_OFFSET,
930 			    cr & (~XAXIDMA_CR_RUNSTOP_MASK));
931 
932 	tasklet_kill(&priv->dma_err_tasklet);
933 
934 	free_irq(priv->tx_irq, ndev);
935 	free_irq(priv->rx_irq, ndev);
936 
937 	nixge_hw_dma_bd_release(ndev);
938 
939 	return 0;
940 }
941 
942 static int nixge_change_mtu(struct net_device *ndev, int new_mtu)
943 {
944 	if (netif_running(ndev))
945 		return -EBUSY;
946 
947 	if ((new_mtu + NIXGE_HDR_SIZE + NIXGE_TRL_SIZE) >
948 	     NIXGE_MAX_JUMBO_FRAME_SIZE)
949 		return -EINVAL;
950 
951 	ndev->mtu = new_mtu;
952 
953 	return 0;
954 }
955 
956 static s32 __nixge_hw_set_mac_address(struct net_device *ndev)
957 {
958 	struct nixge_priv *priv = netdev_priv(ndev);
959 
960 	nixge_ctrl_write_reg(priv, NIXGE_REG_MAC_LSB,
961 			     (ndev->dev_addr[2]) << 24 |
962 			     (ndev->dev_addr[3] << 16) |
963 			     (ndev->dev_addr[4] << 8) |
964 			     (ndev->dev_addr[5] << 0));
965 
966 	nixge_ctrl_write_reg(priv, NIXGE_REG_MAC_MSB,
967 			     (ndev->dev_addr[1] | (ndev->dev_addr[0] << 8)));
968 
969 	return 0;
970 }
971 
972 static int nixge_net_set_mac_address(struct net_device *ndev, void *p)
973 {
974 	int err;
975 
976 	err = eth_mac_addr(ndev, p);
977 	if (!err)
978 		__nixge_hw_set_mac_address(ndev);
979 
980 	return err;
981 }
982 
983 static const struct net_device_ops nixge_netdev_ops = {
984 	.ndo_open = nixge_open,
985 	.ndo_stop = nixge_stop,
986 	.ndo_start_xmit = nixge_start_xmit,
987 	.ndo_change_mtu	= nixge_change_mtu,
988 	.ndo_set_mac_address = nixge_net_set_mac_address,
989 	.ndo_validate_addr = eth_validate_addr,
990 };
991 
992 static void nixge_ethtools_get_drvinfo(struct net_device *ndev,
993 				       struct ethtool_drvinfo *ed)
994 {
995 	strscpy(ed->driver, "nixge", sizeof(ed->driver));
996 	strscpy(ed->bus_info, "platform", sizeof(ed->bus_info));
997 }
998 
999 static int
1000 nixge_ethtools_get_coalesce(struct net_device *ndev,
1001 			    struct ethtool_coalesce *ecoalesce,
1002 			    struct kernel_ethtool_coalesce *kernel_coal,
1003 			    struct netlink_ext_ack *extack)
1004 {
1005 	struct nixge_priv *priv = netdev_priv(ndev);
1006 	u32 regval = 0;
1007 
1008 	regval = nixge_dma_read_reg(priv, XAXIDMA_RX_CR_OFFSET);
1009 	ecoalesce->rx_max_coalesced_frames = (regval & XAXIDMA_COALESCE_MASK)
1010 					     >> XAXIDMA_COALESCE_SHIFT;
1011 	regval = nixge_dma_read_reg(priv, XAXIDMA_TX_CR_OFFSET);
1012 	ecoalesce->tx_max_coalesced_frames = (regval & XAXIDMA_COALESCE_MASK)
1013 					     >> XAXIDMA_COALESCE_SHIFT;
1014 	return 0;
1015 }
1016 
1017 static int
1018 nixge_ethtools_set_coalesce(struct net_device *ndev,
1019 			    struct ethtool_coalesce *ecoalesce,
1020 			    struct kernel_ethtool_coalesce *kernel_coal,
1021 			    struct netlink_ext_ack *extack)
1022 {
1023 	struct nixge_priv *priv = netdev_priv(ndev);
1024 
1025 	if (netif_running(ndev)) {
1026 		netdev_err(ndev,
1027 			   "Please stop netif before applying configuration\n");
1028 		return -EBUSY;
1029 	}
1030 
1031 	if (ecoalesce->rx_max_coalesced_frames)
1032 		priv->coalesce_count_rx = ecoalesce->rx_max_coalesced_frames;
1033 	if (ecoalesce->tx_max_coalesced_frames)
1034 		priv->coalesce_count_tx = ecoalesce->tx_max_coalesced_frames;
1035 
1036 	return 0;
1037 }
1038 
1039 static int nixge_ethtools_set_phys_id(struct net_device *ndev,
1040 				      enum ethtool_phys_id_state state)
1041 {
1042 	struct nixge_priv *priv = netdev_priv(ndev);
1043 	u32 ctrl;
1044 
1045 	ctrl = nixge_ctrl_read_reg(priv, NIXGE_REG_LED_CTL);
1046 	switch (state) {
1047 	case ETHTOOL_ID_ACTIVE:
1048 		ctrl |= NIXGE_ID_LED_CTL_EN;
1049 		/* Enable identification LED override*/
1050 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1051 		return 2;
1052 
1053 	case ETHTOOL_ID_ON:
1054 		ctrl |= NIXGE_ID_LED_CTL_VAL;
1055 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1056 		break;
1057 
1058 	case ETHTOOL_ID_OFF:
1059 		ctrl &= ~NIXGE_ID_LED_CTL_VAL;
1060 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1061 		break;
1062 
1063 	case ETHTOOL_ID_INACTIVE:
1064 		/* Restore LED settings */
1065 		ctrl &= ~NIXGE_ID_LED_CTL_EN;
1066 		nixge_ctrl_write_reg(priv, NIXGE_REG_LED_CTL, ctrl);
1067 		break;
1068 	}
1069 
1070 	return 0;
1071 }
1072 
1073 static const struct ethtool_ops nixge_ethtool_ops = {
1074 	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES,
1075 	.get_drvinfo    = nixge_ethtools_get_drvinfo,
1076 	.get_coalesce   = nixge_ethtools_get_coalesce,
1077 	.set_coalesce   = nixge_ethtools_set_coalesce,
1078 	.set_phys_id    = nixge_ethtools_set_phys_id,
1079 	.get_link_ksettings     = phy_ethtool_get_link_ksettings,
1080 	.set_link_ksettings     = phy_ethtool_set_link_ksettings,
1081 	.get_link		= ethtool_op_get_link,
1082 };
1083 
1084 static int nixge_mdio_read(struct mii_bus *bus, int phy_id, int reg)
1085 {
1086 	struct nixge_priv *priv = bus->priv;
1087 	u32 status, tmp;
1088 	int err;
1089 	u16 device;
1090 
1091 	if (reg & MII_ADDR_C45) {
1092 		device = (reg >> 16) & 0x1f;
1093 
1094 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_ADDR, reg & 0xffff);
1095 
1096 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_OP_ADDRESS)
1097 			| NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1098 
1099 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1100 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1101 
1102 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1103 					      !status, 10, 1000);
1104 		if (err) {
1105 			dev_err(priv->dev, "timeout setting address");
1106 			return err;
1107 		}
1108 
1109 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_C45_READ) |
1110 			NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1111 	} else {
1112 		device = reg & 0x1f;
1113 
1114 		tmp = NIXGE_MDIO_CLAUSE22 | NIXGE_MDIO_OP(NIXGE_MDIO_C22_READ) |
1115 			NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1116 	}
1117 
1118 	nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1119 	nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1120 
1121 	err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1122 				      !status, 10, 1000);
1123 	if (err) {
1124 		dev_err(priv->dev, "timeout setting read command");
1125 		return err;
1126 	}
1127 
1128 	status = nixge_ctrl_read_reg(priv, NIXGE_REG_MDIO_DATA);
1129 
1130 	return status;
1131 }
1132 
1133 static int nixge_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 val)
1134 {
1135 	struct nixge_priv *priv = bus->priv;
1136 	u32 status, tmp;
1137 	u16 device;
1138 	int err;
1139 
1140 	if (reg & MII_ADDR_C45) {
1141 		device = (reg >> 16) & 0x1f;
1142 
1143 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_ADDR, reg & 0xffff);
1144 
1145 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_OP_ADDRESS)
1146 			| NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1147 
1148 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1149 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1150 
1151 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1152 					      !status, 10, 1000);
1153 		if (err) {
1154 			dev_err(priv->dev, "timeout setting address");
1155 			return err;
1156 		}
1157 
1158 		tmp = NIXGE_MDIO_CLAUSE45 | NIXGE_MDIO_OP(NIXGE_MDIO_C45_WRITE)
1159 			| NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1160 
1161 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_DATA, val);
1162 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1163 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1164 					      !status, 10, 1000);
1165 		if (err)
1166 			dev_err(priv->dev, "timeout setting write command");
1167 	} else {
1168 		device = reg & 0x1f;
1169 
1170 		tmp = NIXGE_MDIO_CLAUSE22 |
1171 			NIXGE_MDIO_OP(NIXGE_MDIO_C22_WRITE) |
1172 			NIXGE_MDIO_ADDR(phy_id) | NIXGE_MDIO_MMD(device);
1173 
1174 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_DATA, val);
1175 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_OP, tmp);
1176 		nixge_ctrl_write_reg(priv, NIXGE_REG_MDIO_CTRL, 1);
1177 
1178 		err = nixge_ctrl_poll_timeout(priv, NIXGE_REG_MDIO_CTRL, status,
1179 					      !status, 10, 1000);
1180 		if (err)
1181 			dev_err(priv->dev, "timeout setting write command");
1182 	}
1183 
1184 	return err;
1185 }
1186 
1187 static int nixge_mdio_setup(struct nixge_priv *priv, struct device_node *np)
1188 {
1189 	struct mii_bus *bus;
1190 
1191 	bus = devm_mdiobus_alloc(priv->dev);
1192 	if (!bus)
1193 		return -ENOMEM;
1194 
1195 	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(priv->dev));
1196 	bus->priv = priv;
1197 	bus->name = "nixge_mii_bus";
1198 	bus->read = nixge_mdio_read;
1199 	bus->write = nixge_mdio_write;
1200 	bus->parent = priv->dev;
1201 
1202 	priv->mii_bus = bus;
1203 
1204 	return of_mdiobus_register(bus, np);
1205 }
1206 
1207 static void *nixge_get_nvmem_address(struct device *dev)
1208 {
1209 	struct nvmem_cell *cell;
1210 	size_t cell_size;
1211 	char *mac;
1212 
1213 	cell = nvmem_cell_get(dev, "address");
1214 	if (IS_ERR(cell))
1215 		return cell;
1216 
1217 	mac = nvmem_cell_read(cell, &cell_size);
1218 	nvmem_cell_put(cell);
1219 
1220 	return mac;
1221 }
1222 
1223 /* Match table for of_platform binding */
1224 static const struct of_device_id nixge_dt_ids[] = {
1225 	{ .compatible = "ni,xge-enet-2.00", .data = (void *)NIXGE_V2 },
1226 	{ .compatible = "ni,xge-enet-3.00", .data = (void *)NIXGE_V3 },
1227 	{},
1228 };
1229 MODULE_DEVICE_TABLE(of, nixge_dt_ids);
1230 
1231 static int nixge_of_get_resources(struct platform_device *pdev)
1232 {
1233 	const struct of_device_id *of_id;
1234 	enum nixge_version version;
1235 	struct net_device *ndev;
1236 	struct nixge_priv *priv;
1237 
1238 	ndev = platform_get_drvdata(pdev);
1239 	priv = netdev_priv(ndev);
1240 	of_id = of_match_node(nixge_dt_ids, pdev->dev.of_node);
1241 	if (!of_id)
1242 		return -ENODEV;
1243 
1244 	version = (enum nixge_version)of_id->data;
1245 	if (version <= NIXGE_V2)
1246 		priv->dma_regs = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
1247 	else
1248 		priv->dma_regs = devm_platform_ioremap_resource_byname(pdev, "dma");
1249 	if (IS_ERR(priv->dma_regs)) {
1250 		netdev_err(ndev, "failed to map dma regs\n");
1251 		return PTR_ERR(priv->dma_regs);
1252 	}
1253 	if (version <= NIXGE_V2)
1254 		priv->ctrl_regs = priv->dma_regs + NIXGE_REG_CTRL_OFFSET;
1255 	else
1256 		priv->ctrl_regs = devm_platform_ioremap_resource_byname(pdev, "ctrl");
1257 	if (IS_ERR(priv->ctrl_regs)) {
1258 		netdev_err(ndev, "failed to map ctrl regs\n");
1259 		return PTR_ERR(priv->ctrl_regs);
1260 	}
1261 	return 0;
1262 }
1263 
1264 static int nixge_probe(struct platform_device *pdev)
1265 {
1266 	struct device_node *mn, *phy_node;
1267 	struct nixge_priv *priv;
1268 	struct net_device *ndev;
1269 	const u8 *mac_addr;
1270 	int err;
1271 
1272 	ndev = alloc_etherdev(sizeof(*priv));
1273 	if (!ndev)
1274 		return -ENOMEM;
1275 
1276 	platform_set_drvdata(pdev, ndev);
1277 	SET_NETDEV_DEV(ndev, &pdev->dev);
1278 
1279 	ndev->features = NETIF_F_SG;
1280 	ndev->netdev_ops = &nixge_netdev_ops;
1281 	ndev->ethtool_ops = &nixge_ethtool_ops;
1282 
1283 	/* MTU range: 64 - 9000 */
1284 	ndev->min_mtu = 64;
1285 	ndev->max_mtu = NIXGE_JUMBO_MTU;
1286 
1287 	mac_addr = nixge_get_nvmem_address(&pdev->dev);
1288 	if (!IS_ERR(mac_addr) && is_valid_ether_addr(mac_addr)) {
1289 		eth_hw_addr_set(ndev, mac_addr);
1290 		kfree(mac_addr);
1291 	} else {
1292 		eth_hw_addr_random(ndev);
1293 	}
1294 
1295 	priv = netdev_priv(ndev);
1296 	priv->ndev = ndev;
1297 	priv->dev = &pdev->dev;
1298 
1299 	netif_napi_add(ndev, &priv->napi, nixge_poll);
1300 	err = nixge_of_get_resources(pdev);
1301 	if (err)
1302 		goto free_netdev;
1303 	__nixge_hw_set_mac_address(ndev);
1304 
1305 	priv->tx_irq = platform_get_irq_byname(pdev, "tx");
1306 	if (priv->tx_irq < 0) {
1307 		netdev_err(ndev, "could not find 'tx' irq");
1308 		err = priv->tx_irq;
1309 		goto free_netdev;
1310 	}
1311 
1312 	priv->rx_irq = platform_get_irq_byname(pdev, "rx");
1313 	if (priv->rx_irq < 0) {
1314 		netdev_err(ndev, "could not find 'rx' irq");
1315 		err = priv->rx_irq;
1316 		goto free_netdev;
1317 	}
1318 
1319 	priv->coalesce_count_rx = XAXIDMA_DFT_RX_THRESHOLD;
1320 	priv->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD;
1321 
1322 	mn = of_get_child_by_name(pdev->dev.of_node, "mdio");
1323 	if (mn) {
1324 		err = nixge_mdio_setup(priv, mn);
1325 		of_node_put(mn);
1326 		if (err) {
1327 			netdev_err(ndev, "error registering mdio bus");
1328 			goto free_netdev;
1329 		}
1330 	}
1331 
1332 	err = of_get_phy_mode(pdev->dev.of_node, &priv->phy_mode);
1333 	if (err) {
1334 		netdev_err(ndev, "not find \"phy-mode\" property\n");
1335 		goto unregister_mdio;
1336 	}
1337 
1338 	phy_node = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
1339 	if (!phy_node && of_phy_is_fixed_link(pdev->dev.of_node)) {
1340 		err = of_phy_register_fixed_link(pdev->dev.of_node);
1341 		if (err < 0) {
1342 			netdev_err(ndev, "broken fixed-link specification\n");
1343 			goto unregister_mdio;
1344 		}
1345 		phy_node = of_node_get(pdev->dev.of_node);
1346 	}
1347 	priv->phy_node = phy_node;
1348 
1349 	err = register_netdev(priv->ndev);
1350 	if (err) {
1351 		netdev_err(ndev, "register_netdev() error (%i)\n", err);
1352 		goto free_phy;
1353 	}
1354 
1355 	return 0;
1356 
1357 free_phy:
1358 	if (of_phy_is_fixed_link(pdev->dev.of_node))
1359 		of_phy_deregister_fixed_link(pdev->dev.of_node);
1360 	of_node_put(phy_node);
1361 
1362 unregister_mdio:
1363 	if (priv->mii_bus)
1364 		mdiobus_unregister(priv->mii_bus);
1365 
1366 free_netdev:
1367 	free_netdev(ndev);
1368 
1369 	return err;
1370 }
1371 
1372 static int nixge_remove(struct platform_device *pdev)
1373 {
1374 	struct net_device *ndev = platform_get_drvdata(pdev);
1375 	struct nixge_priv *priv = netdev_priv(ndev);
1376 
1377 	unregister_netdev(ndev);
1378 
1379 	if (of_phy_is_fixed_link(pdev->dev.of_node))
1380 		of_phy_deregister_fixed_link(pdev->dev.of_node);
1381 	of_node_put(priv->phy_node);
1382 
1383 	if (priv->mii_bus)
1384 		mdiobus_unregister(priv->mii_bus);
1385 
1386 	free_netdev(ndev);
1387 
1388 	return 0;
1389 }
1390 
1391 static struct platform_driver nixge_driver = {
1392 	.probe		= nixge_probe,
1393 	.remove		= nixge_remove,
1394 	.driver		= {
1395 		.name		= "nixge",
1396 		.of_match_table	= of_match_ptr(nixge_dt_ids),
1397 	},
1398 };
1399 module_platform_driver(nixge_driver);
1400 
1401 MODULE_LICENSE("GPL v2");
1402 MODULE_DESCRIPTION("National Instruments XGE Management MAC");
1403 MODULE_AUTHOR("Moritz Fischer <mdf@kernel.org>");
1404