1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Xilinx Axi Ethernet device driver
4  *
5  * Copyright (c) 2008 Nissin Systems Co., Ltd.,  Yoshio Kashiwagi
6  * Copyright (c) 2005-2008 DLA Systems,  David H. Lynch Jr. <dhlii@dlasys.net>
7  * Copyright (c) 2008-2009 Secret Lab Technologies Ltd.
8  * Copyright (c) 2010 - 2011 Michal Simek <monstr@monstr.eu>
9  * Copyright (c) 2010 - 2011 PetaLogix
10  * Copyright (c) 2019 SED Systems, a division of Calian Ltd.
11  * Copyright (c) 2010 - 2012 Xilinx, Inc. All rights reserved.
12  *
13  * This is a driver for the Xilinx Axi Ethernet which is used in the Virtex6
14  * and Spartan6.
15  *
16  * TODO:
17  *  - Add Axi Fifo support.
18  *  - Factor out Axi DMA code into separate driver.
19  *  - Test and fix basic multicast filtering.
20  *  - Add support for extended multicast filtering.
21  *  - Test basic VLAN support.
22  *  - Add support for extended VLAN support.
23  */
24 
25 #include <linux/clk.h>
26 #include <linux/delay.h>
27 #include <linux/etherdevice.h>
28 #include <linux/module.h>
29 #include <linux/netdevice.h>
30 #include <linux/of_mdio.h>
31 #include <linux/of_net.h>
32 #include <linux/of_platform.h>
33 #include <linux/of_irq.h>
34 #include <linux/of_address.h>
35 #include <linux/skbuff.h>
36 #include <linux/spinlock.h>
37 #include <linux/phy.h>
38 #include <linux/mii.h>
39 #include <linux/ethtool.h>
40 
41 #include "xilinx_axienet.h"
42 
43 /* Descriptors defines for Tx and Rx DMA */
44 #define TX_BD_NUM_DEFAULT		64
45 #define RX_BD_NUM_DEFAULT		1024
46 #define TX_BD_NUM_MAX			4096
47 #define RX_BD_NUM_MAX			4096
48 
49 /* Must be shorter than length of ethtool_drvinfo.driver field to fit */
50 #define DRIVER_NAME		"xaxienet"
51 #define DRIVER_DESCRIPTION	"Xilinx Axi Ethernet driver"
52 #define DRIVER_VERSION		"1.00a"
53 
54 #define AXIENET_REGS_N		40
55 
56 /* Match table for of_platform binding */
57 static const struct of_device_id axienet_of_match[] = {
58 	{ .compatible = "xlnx,axi-ethernet-1.00.a", },
59 	{ .compatible = "xlnx,axi-ethernet-1.01.a", },
60 	{ .compatible = "xlnx,axi-ethernet-2.01.a", },
61 	{},
62 };
63 
64 MODULE_DEVICE_TABLE(of, axienet_of_match);
65 
66 /* Option table for setting up Axi Ethernet hardware options */
67 static struct axienet_option axienet_options[] = {
68 	/* Turn on jumbo packet support for both Rx and Tx */
69 	{
70 		.opt = XAE_OPTION_JUMBO,
71 		.reg = XAE_TC_OFFSET,
72 		.m_or = XAE_TC_JUM_MASK,
73 	}, {
74 		.opt = XAE_OPTION_JUMBO,
75 		.reg = XAE_RCW1_OFFSET,
76 		.m_or = XAE_RCW1_JUM_MASK,
77 	}, { /* Turn on VLAN packet support for both Rx and Tx */
78 		.opt = XAE_OPTION_VLAN,
79 		.reg = XAE_TC_OFFSET,
80 		.m_or = XAE_TC_VLAN_MASK,
81 	}, {
82 		.opt = XAE_OPTION_VLAN,
83 		.reg = XAE_RCW1_OFFSET,
84 		.m_or = XAE_RCW1_VLAN_MASK,
85 	}, { /* Turn on FCS stripping on receive packets */
86 		.opt = XAE_OPTION_FCS_STRIP,
87 		.reg = XAE_RCW1_OFFSET,
88 		.m_or = XAE_RCW1_FCS_MASK,
89 	}, { /* Turn on FCS insertion on transmit packets */
90 		.opt = XAE_OPTION_FCS_INSERT,
91 		.reg = XAE_TC_OFFSET,
92 		.m_or = XAE_TC_FCS_MASK,
93 	}, { /* Turn off length/type field checking on receive packets */
94 		.opt = XAE_OPTION_LENTYPE_ERR,
95 		.reg = XAE_RCW1_OFFSET,
96 		.m_or = XAE_RCW1_LT_DIS_MASK,
97 	}, { /* Turn on Rx flow control */
98 		.opt = XAE_OPTION_FLOW_CONTROL,
99 		.reg = XAE_FCC_OFFSET,
100 		.m_or = XAE_FCC_FCRX_MASK,
101 	}, { /* Turn on Tx flow control */
102 		.opt = XAE_OPTION_FLOW_CONTROL,
103 		.reg = XAE_FCC_OFFSET,
104 		.m_or = XAE_FCC_FCTX_MASK,
105 	}, { /* Turn on promiscuous frame filtering */
106 		.opt = XAE_OPTION_PROMISC,
107 		.reg = XAE_FMI_OFFSET,
108 		.m_or = XAE_FMI_PM_MASK,
109 	}, { /* Enable transmitter */
110 		.opt = XAE_OPTION_TXEN,
111 		.reg = XAE_TC_OFFSET,
112 		.m_or = XAE_TC_TX_MASK,
113 	}, { /* Enable receiver */
114 		.opt = XAE_OPTION_RXEN,
115 		.reg = XAE_RCW1_OFFSET,
116 		.m_or = XAE_RCW1_RX_MASK,
117 	},
118 	{}
119 };
120 
121 /**
122  * axienet_dma_in32 - Memory mapped Axi DMA register read
123  * @lp:		Pointer to axienet local structure
124  * @reg:	Address offset from the base address of the Axi DMA core
125  *
126  * Return: The contents of the Axi DMA register
127  *
128  * This function returns the contents of the corresponding Axi DMA register.
129  */
130 static inline u32 axienet_dma_in32(struct axienet_local *lp, off_t reg)
131 {
132 	return ioread32(lp->dma_regs + reg);
133 }
134 
135 /**
136  * axienet_dma_out32 - Memory mapped Axi DMA register write.
137  * @lp:		Pointer to axienet local structure
138  * @reg:	Address offset from the base address of the Axi DMA core
139  * @value:	Value to be written into the Axi DMA register
140  *
141  * This function writes the desired value into the corresponding Axi DMA
142  * register.
143  */
144 static inline void axienet_dma_out32(struct axienet_local *lp,
145 				     off_t reg, u32 value)
146 {
147 	iowrite32(value, lp->dma_regs + reg);
148 }
149 
150 static void axienet_dma_out_addr(struct axienet_local *lp, off_t reg,
151 				 dma_addr_t addr)
152 {
153 	axienet_dma_out32(lp, reg, lower_32_bits(addr));
154 
155 	if (lp->features & XAE_FEATURE_DMA_64BIT)
156 		axienet_dma_out32(lp, reg + 4, upper_32_bits(addr));
157 }
158 
159 static void desc_set_phys_addr(struct axienet_local *lp, dma_addr_t addr,
160 			       struct axidma_bd *desc)
161 {
162 	desc->phys = lower_32_bits(addr);
163 	if (lp->features & XAE_FEATURE_DMA_64BIT)
164 		desc->phys_msb = upper_32_bits(addr);
165 }
166 
167 static dma_addr_t desc_get_phys_addr(struct axienet_local *lp,
168 				     struct axidma_bd *desc)
169 {
170 	dma_addr_t ret = desc->phys;
171 
172 	if (lp->features & XAE_FEATURE_DMA_64BIT)
173 		ret |= ((dma_addr_t)desc->phys_msb << 16) << 16;
174 
175 	return ret;
176 }
177 
178 /**
179  * axienet_dma_bd_release - Release buffer descriptor rings
180  * @ndev:	Pointer to the net_device structure
181  *
182  * This function is used to release the descriptors allocated in
183  * axienet_dma_bd_init. axienet_dma_bd_release is called when Axi Ethernet
184  * driver stop api is called.
185  */
186 static void axienet_dma_bd_release(struct net_device *ndev)
187 {
188 	int i;
189 	struct axienet_local *lp = netdev_priv(ndev);
190 
191 	/* If we end up here, tx_bd_v must have been DMA allocated. */
192 	dma_free_coherent(ndev->dev.parent,
193 			  sizeof(*lp->tx_bd_v) * lp->tx_bd_num,
194 			  lp->tx_bd_v,
195 			  lp->tx_bd_p);
196 
197 	if (!lp->rx_bd_v)
198 		return;
199 
200 	for (i = 0; i < lp->rx_bd_num; i++) {
201 		dma_addr_t phys;
202 
203 		/* A NULL skb means this descriptor has not been initialised
204 		 * at all.
205 		 */
206 		if (!lp->rx_bd_v[i].skb)
207 			break;
208 
209 		dev_kfree_skb(lp->rx_bd_v[i].skb);
210 
211 		/* For each descriptor, we programmed cntrl with the (non-zero)
212 		 * descriptor size, after it had been successfully allocated.
213 		 * So a non-zero value in there means we need to unmap it.
214 		 */
215 		if (lp->rx_bd_v[i].cntrl) {
216 			phys = desc_get_phys_addr(lp, &lp->rx_bd_v[i]);
217 			dma_unmap_single(ndev->dev.parent, phys,
218 					 lp->max_frm_size, DMA_FROM_DEVICE);
219 		}
220 	}
221 
222 	dma_free_coherent(ndev->dev.parent,
223 			  sizeof(*lp->rx_bd_v) * lp->rx_bd_num,
224 			  lp->rx_bd_v,
225 			  lp->rx_bd_p);
226 }
227 
228 /**
229  * axienet_dma_bd_init - Setup buffer descriptor rings for Axi DMA
230  * @ndev:	Pointer to the net_device structure
231  *
232  * Return: 0, on success -ENOMEM, on failure
233  *
234  * This function is called to initialize the Rx and Tx DMA descriptor
235  * rings. This initializes the descriptors with required default values
236  * and is called when Axi Ethernet driver reset is called.
237  */
238 static int axienet_dma_bd_init(struct net_device *ndev)
239 {
240 	u32 cr;
241 	int i;
242 	struct sk_buff *skb;
243 	struct axienet_local *lp = netdev_priv(ndev);
244 
245 	/* Reset the indexes which are used for accessing the BDs */
246 	lp->tx_bd_ci = 0;
247 	lp->tx_bd_tail = 0;
248 	lp->rx_bd_ci = 0;
249 
250 	/* Allocate the Tx and Rx buffer descriptors. */
251 	lp->tx_bd_v = dma_alloc_coherent(ndev->dev.parent,
252 					 sizeof(*lp->tx_bd_v) * lp->tx_bd_num,
253 					 &lp->tx_bd_p, GFP_KERNEL);
254 	if (!lp->tx_bd_v)
255 		return -ENOMEM;
256 
257 	lp->rx_bd_v = dma_alloc_coherent(ndev->dev.parent,
258 					 sizeof(*lp->rx_bd_v) * lp->rx_bd_num,
259 					 &lp->rx_bd_p, GFP_KERNEL);
260 	if (!lp->rx_bd_v)
261 		goto out;
262 
263 	for (i = 0; i < lp->tx_bd_num; i++) {
264 		dma_addr_t addr = lp->tx_bd_p +
265 				  sizeof(*lp->tx_bd_v) *
266 				  ((i + 1) % lp->tx_bd_num);
267 
268 		lp->tx_bd_v[i].next = lower_32_bits(addr);
269 		if (lp->features & XAE_FEATURE_DMA_64BIT)
270 			lp->tx_bd_v[i].next_msb = upper_32_bits(addr);
271 	}
272 
273 	for (i = 0; i < lp->rx_bd_num; i++) {
274 		dma_addr_t addr;
275 
276 		addr = lp->rx_bd_p + sizeof(*lp->rx_bd_v) *
277 			((i + 1) % lp->rx_bd_num);
278 		lp->rx_bd_v[i].next = lower_32_bits(addr);
279 		if (lp->features & XAE_FEATURE_DMA_64BIT)
280 			lp->rx_bd_v[i].next_msb = upper_32_bits(addr);
281 
282 		skb = netdev_alloc_skb_ip_align(ndev, lp->max_frm_size);
283 		if (!skb)
284 			goto out;
285 
286 		lp->rx_bd_v[i].skb = skb;
287 		addr = dma_map_single(ndev->dev.parent, skb->data,
288 				      lp->max_frm_size, DMA_FROM_DEVICE);
289 		if (dma_mapping_error(ndev->dev.parent, addr)) {
290 			netdev_err(ndev, "DMA mapping error\n");
291 			goto out;
292 		}
293 		desc_set_phys_addr(lp, addr, &lp->rx_bd_v[i]);
294 
295 		lp->rx_bd_v[i].cntrl = lp->max_frm_size;
296 	}
297 
298 	/* Start updating the Rx channel control register */
299 	cr = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
300 	/* Update the interrupt coalesce count */
301 	cr = ((cr & ~XAXIDMA_COALESCE_MASK) |
302 	      ((lp->coalesce_count_rx) << XAXIDMA_COALESCE_SHIFT));
303 	/* Update the delay timer count */
304 	cr = ((cr & ~XAXIDMA_DELAY_MASK) |
305 	      (XAXIDMA_DFT_RX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
306 	/* Enable coalesce, delay timer and error interrupts */
307 	cr |= XAXIDMA_IRQ_ALL_MASK;
308 	/* Write to the Rx channel control register */
309 	axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, cr);
310 
311 	/* Start updating the Tx channel control register */
312 	cr = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
313 	/* Update the interrupt coalesce count */
314 	cr = (((cr & ~XAXIDMA_COALESCE_MASK)) |
315 	      ((lp->coalesce_count_tx) << XAXIDMA_COALESCE_SHIFT));
316 	/* Update the delay timer count */
317 	cr = (((cr & ~XAXIDMA_DELAY_MASK)) |
318 	      (XAXIDMA_DFT_TX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
319 	/* Enable coalesce, delay timer and error interrupts */
320 	cr |= XAXIDMA_IRQ_ALL_MASK;
321 	/* Write to the Tx channel control register */
322 	axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET, cr);
323 
324 	/* Populate the tail pointer and bring the Rx Axi DMA engine out of
325 	 * halted state. This will make the Rx side ready for reception.
326 	 */
327 	axienet_dma_out_addr(lp, XAXIDMA_RX_CDESC_OFFSET, lp->rx_bd_p);
328 	cr = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
329 	axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET,
330 			  cr | XAXIDMA_CR_RUNSTOP_MASK);
331 	axienet_dma_out_addr(lp, XAXIDMA_RX_TDESC_OFFSET, lp->rx_bd_p +
332 			     (sizeof(*lp->rx_bd_v) * (lp->rx_bd_num - 1)));
333 
334 	/* Write to the RS (Run-stop) bit in the Tx channel control register.
335 	 * Tx channel is now ready to run. But only after we write to the
336 	 * tail pointer register that the Tx channel will start transmitting.
337 	 */
338 	axienet_dma_out_addr(lp, XAXIDMA_TX_CDESC_OFFSET, lp->tx_bd_p);
339 	cr = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
340 	axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET,
341 			  cr | XAXIDMA_CR_RUNSTOP_MASK);
342 
343 	return 0;
344 out:
345 	axienet_dma_bd_release(ndev);
346 	return -ENOMEM;
347 }
348 
349 /**
350  * axienet_set_mac_address - Write the MAC address
351  * @ndev:	Pointer to the net_device structure
352  * @address:	6 byte Address to be written as MAC address
353  *
354  * This function is called to initialize the MAC address of the Axi Ethernet
355  * core. It writes to the UAW0 and UAW1 registers of the core.
356  */
357 static void axienet_set_mac_address(struct net_device *ndev,
358 				    const void *address)
359 {
360 	struct axienet_local *lp = netdev_priv(ndev);
361 
362 	if (address)
363 		memcpy(ndev->dev_addr, address, ETH_ALEN);
364 	if (!is_valid_ether_addr(ndev->dev_addr))
365 		eth_hw_addr_random(ndev);
366 
367 	/* Set up unicast MAC address filter set its mac address */
368 	axienet_iow(lp, XAE_UAW0_OFFSET,
369 		    (ndev->dev_addr[0]) |
370 		    (ndev->dev_addr[1] << 8) |
371 		    (ndev->dev_addr[2] << 16) |
372 		    (ndev->dev_addr[3] << 24));
373 	axienet_iow(lp, XAE_UAW1_OFFSET,
374 		    (((axienet_ior(lp, XAE_UAW1_OFFSET)) &
375 		      ~XAE_UAW1_UNICASTADDR_MASK) |
376 		     (ndev->dev_addr[4] |
377 		     (ndev->dev_addr[5] << 8))));
378 }
379 
380 /**
381  * netdev_set_mac_address - Write the MAC address (from outside the driver)
382  * @ndev:	Pointer to the net_device structure
383  * @p:		6 byte Address to be written as MAC address
384  *
385  * Return: 0 for all conditions. Presently, there is no failure case.
386  *
387  * This function is called to initialize the MAC address of the Axi Ethernet
388  * core. It calls the core specific axienet_set_mac_address. This is the
389  * function that goes into net_device_ops structure entry ndo_set_mac_address.
390  */
391 static int netdev_set_mac_address(struct net_device *ndev, void *p)
392 {
393 	struct sockaddr *addr = p;
394 	axienet_set_mac_address(ndev, addr->sa_data);
395 	return 0;
396 }
397 
398 /**
399  * axienet_set_multicast_list - Prepare the multicast table
400  * @ndev:	Pointer to the net_device structure
401  *
402  * This function is called to initialize the multicast table during
403  * initialization. The Axi Ethernet basic multicast support has a four-entry
404  * multicast table which is initialized here. Additionally this function
405  * goes into the net_device_ops structure entry ndo_set_multicast_list. This
406  * means whenever the multicast table entries need to be updated this
407  * function gets called.
408  */
409 static void axienet_set_multicast_list(struct net_device *ndev)
410 {
411 	int i;
412 	u32 reg, af0reg, af1reg;
413 	struct axienet_local *lp = netdev_priv(ndev);
414 
415 	if (ndev->flags & (IFF_ALLMULTI | IFF_PROMISC) ||
416 	    netdev_mc_count(ndev) > XAE_MULTICAST_CAM_TABLE_NUM) {
417 		/* We must make the kernel realize we had to move into
418 		 * promiscuous mode. If it was a promiscuous mode request
419 		 * the flag is already set. If not we set it.
420 		 */
421 		ndev->flags |= IFF_PROMISC;
422 		reg = axienet_ior(lp, XAE_FMI_OFFSET);
423 		reg |= XAE_FMI_PM_MASK;
424 		axienet_iow(lp, XAE_FMI_OFFSET, reg);
425 		dev_info(&ndev->dev, "Promiscuous mode enabled.\n");
426 	} else if (!netdev_mc_empty(ndev)) {
427 		struct netdev_hw_addr *ha;
428 
429 		i = 0;
430 		netdev_for_each_mc_addr(ha, ndev) {
431 			if (i >= XAE_MULTICAST_CAM_TABLE_NUM)
432 				break;
433 
434 			af0reg = (ha->addr[0]);
435 			af0reg |= (ha->addr[1] << 8);
436 			af0reg |= (ha->addr[2] << 16);
437 			af0reg |= (ha->addr[3] << 24);
438 
439 			af1reg = (ha->addr[4]);
440 			af1reg |= (ha->addr[5] << 8);
441 
442 			reg = axienet_ior(lp, XAE_FMI_OFFSET) & 0xFFFFFF00;
443 			reg |= i;
444 
445 			axienet_iow(lp, XAE_FMI_OFFSET, reg);
446 			axienet_iow(lp, XAE_AF0_OFFSET, af0reg);
447 			axienet_iow(lp, XAE_AF1_OFFSET, af1reg);
448 			i++;
449 		}
450 	} else {
451 		reg = axienet_ior(lp, XAE_FMI_OFFSET);
452 		reg &= ~XAE_FMI_PM_MASK;
453 
454 		axienet_iow(lp, XAE_FMI_OFFSET, reg);
455 
456 		for (i = 0; i < XAE_MULTICAST_CAM_TABLE_NUM; i++) {
457 			reg = axienet_ior(lp, XAE_FMI_OFFSET) & 0xFFFFFF00;
458 			reg |= i;
459 
460 			axienet_iow(lp, XAE_FMI_OFFSET, reg);
461 			axienet_iow(lp, XAE_AF0_OFFSET, 0);
462 			axienet_iow(lp, XAE_AF1_OFFSET, 0);
463 		}
464 
465 		dev_info(&ndev->dev, "Promiscuous mode disabled.\n");
466 	}
467 }
468 
469 /**
470  * axienet_setoptions - Set an Axi Ethernet option
471  * @ndev:	Pointer to the net_device structure
472  * @options:	Option to be enabled/disabled
473  *
474  * The Axi Ethernet core has multiple features which can be selectively turned
475  * on or off. The typical options could be jumbo frame option, basic VLAN
476  * option, promiscuous mode option etc. This function is used to set or clear
477  * these options in the Axi Ethernet hardware. This is done through
478  * axienet_option structure .
479  */
480 static void axienet_setoptions(struct net_device *ndev, u32 options)
481 {
482 	int reg;
483 	struct axienet_local *lp = netdev_priv(ndev);
484 	struct axienet_option *tp = &axienet_options[0];
485 
486 	while (tp->opt) {
487 		reg = ((axienet_ior(lp, tp->reg)) & ~(tp->m_or));
488 		if (options & tp->opt)
489 			reg |= tp->m_or;
490 		axienet_iow(lp, tp->reg, reg);
491 		tp++;
492 	}
493 
494 	lp->options |= options;
495 }
496 
497 static int __axienet_device_reset(struct axienet_local *lp)
498 {
499 	u32 timeout;
500 
501 	/* Reset Axi DMA. This would reset Axi Ethernet core as well. The reset
502 	 * process of Axi DMA takes a while to complete as all pending
503 	 * commands/transfers will be flushed or completed during this
504 	 * reset process.
505 	 * Note that even though both TX and RX have their own reset register,
506 	 * they both reset the entire DMA core, so only one needs to be used.
507 	 */
508 	axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET, XAXIDMA_CR_RESET_MASK);
509 	timeout = DELAY_OF_ONE_MILLISEC;
510 	while (axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET) &
511 				XAXIDMA_CR_RESET_MASK) {
512 		udelay(1);
513 		if (--timeout == 0) {
514 			netdev_err(lp->ndev, "%s: DMA reset timeout!\n",
515 				   __func__);
516 			return -ETIMEDOUT;
517 		}
518 	}
519 
520 	return 0;
521 }
522 
523 /**
524  * axienet_device_reset - Reset and initialize the Axi Ethernet hardware.
525  * @ndev:	Pointer to the net_device structure
526  *
527  * This function is called to reset and initialize the Axi Ethernet core. This
528  * is typically called during initialization. It does a reset of the Axi DMA
529  * Rx/Tx channels and initializes the Axi DMA BDs. Since Axi DMA reset lines
530  * areconnected to Axi Ethernet reset lines, this in turn resets the Axi
531  * Ethernet core. No separate hardware reset is done for the Axi Ethernet
532  * core.
533  * Returns 0 on success or a negative error number otherwise.
534  */
535 static int axienet_device_reset(struct net_device *ndev)
536 {
537 	u32 axienet_status;
538 	struct axienet_local *lp = netdev_priv(ndev);
539 	int ret;
540 
541 	ret = __axienet_device_reset(lp);
542 	if (ret)
543 		return ret;
544 
545 	lp->max_frm_size = XAE_MAX_VLAN_FRAME_SIZE;
546 	lp->options |= XAE_OPTION_VLAN;
547 	lp->options &= (~XAE_OPTION_JUMBO);
548 
549 	if ((ndev->mtu > XAE_MTU) &&
550 		(ndev->mtu <= XAE_JUMBO_MTU)) {
551 		lp->max_frm_size = ndev->mtu + VLAN_ETH_HLEN +
552 					XAE_TRL_SIZE;
553 
554 		if (lp->max_frm_size <= lp->rxmem)
555 			lp->options |= XAE_OPTION_JUMBO;
556 	}
557 
558 	ret = axienet_dma_bd_init(ndev);
559 	if (ret) {
560 		netdev_err(ndev, "%s: descriptor allocation failed\n",
561 			   __func__);
562 		return ret;
563 	}
564 
565 	axienet_status = axienet_ior(lp, XAE_RCW1_OFFSET);
566 	axienet_status &= ~XAE_RCW1_RX_MASK;
567 	axienet_iow(lp, XAE_RCW1_OFFSET, axienet_status);
568 
569 	axienet_status = axienet_ior(lp, XAE_IP_OFFSET);
570 	if (axienet_status & XAE_INT_RXRJECT_MASK)
571 		axienet_iow(lp, XAE_IS_OFFSET, XAE_INT_RXRJECT_MASK);
572 	axienet_iow(lp, XAE_IE_OFFSET, lp->eth_irq > 0 ?
573 		    XAE_INT_RECV_ERROR_MASK : 0);
574 
575 	axienet_iow(lp, XAE_FCC_OFFSET, XAE_FCC_FCRX_MASK);
576 
577 	/* Sync default options with HW but leave receiver and
578 	 * transmitter disabled.
579 	 */
580 	axienet_setoptions(ndev, lp->options &
581 			   ~(XAE_OPTION_TXEN | XAE_OPTION_RXEN));
582 	axienet_set_mac_address(ndev, NULL);
583 	axienet_set_multicast_list(ndev);
584 	axienet_setoptions(ndev, lp->options);
585 
586 	netif_trans_update(ndev);
587 
588 	return 0;
589 }
590 
591 /**
592  * axienet_free_tx_chain - Clean up a series of linked TX descriptors.
593  * @ndev:	Pointer to the net_device structure
594  * @first_bd:	Index of first descriptor to clean up
595  * @nr_bds:	Number of descriptors to clean up, can be -1 if unknown.
596  * @sizep:	Pointer to a u32 filled with the total sum of all bytes
597  * 		in all cleaned-up descriptors. Ignored if NULL.
598  *
599  * Would either be called after a successful transmit operation, or after
600  * there was an error when setting up the chain.
601  * Returns the number of descriptors handled.
602  */
603 static int axienet_free_tx_chain(struct net_device *ndev, u32 first_bd,
604 				 int nr_bds, u32 *sizep)
605 {
606 	struct axienet_local *lp = netdev_priv(ndev);
607 	struct axidma_bd *cur_p;
608 	int max_bds = nr_bds;
609 	unsigned int status;
610 	dma_addr_t phys;
611 	int i;
612 
613 	if (max_bds == -1)
614 		max_bds = lp->tx_bd_num;
615 
616 	for (i = 0; i < max_bds; i++) {
617 		cur_p = &lp->tx_bd_v[(first_bd + i) % lp->tx_bd_num];
618 		status = cur_p->status;
619 
620 		/* If no number is given, clean up *all* descriptors that have
621 		 * been completed by the MAC.
622 		 */
623 		if (nr_bds == -1 && !(status & XAXIDMA_BD_STS_COMPLETE_MASK))
624 			break;
625 
626 		phys = desc_get_phys_addr(lp, cur_p);
627 		dma_unmap_single(ndev->dev.parent, phys,
628 				 (cur_p->cntrl & XAXIDMA_BD_CTRL_LENGTH_MASK),
629 				 DMA_TO_DEVICE);
630 
631 		if (cur_p->skb && (status & XAXIDMA_BD_STS_COMPLETE_MASK))
632 			dev_consume_skb_irq(cur_p->skb);
633 
634 		cur_p->cntrl = 0;
635 		cur_p->app0 = 0;
636 		cur_p->app1 = 0;
637 		cur_p->app2 = 0;
638 		cur_p->app4 = 0;
639 		cur_p->status = 0;
640 		cur_p->skb = NULL;
641 
642 		if (sizep)
643 			*sizep += status & XAXIDMA_BD_STS_ACTUAL_LEN_MASK;
644 	}
645 
646 	return i;
647 }
648 
649 /**
650  * axienet_start_xmit_done - Invoked once a transmit is completed by the
651  * Axi DMA Tx channel.
652  * @ndev:	Pointer to the net_device structure
653  *
654  * This function is invoked from the Axi DMA Tx isr to notify the completion
655  * of transmit operation. It clears fields in the corresponding Tx BDs and
656  * unmaps the corresponding buffer so that CPU can regain ownership of the
657  * buffer. It finally invokes "netif_wake_queue" to restart transmission if
658  * required.
659  */
660 static void axienet_start_xmit_done(struct net_device *ndev)
661 {
662 	struct axienet_local *lp = netdev_priv(ndev);
663 	u32 packets = 0;
664 	u32 size = 0;
665 
666 	packets = axienet_free_tx_chain(ndev, lp->tx_bd_ci, -1, &size);
667 
668 	lp->tx_bd_ci += packets;
669 	if (lp->tx_bd_ci >= lp->tx_bd_num)
670 		lp->tx_bd_ci -= lp->tx_bd_num;
671 
672 	ndev->stats.tx_packets += packets;
673 	ndev->stats.tx_bytes += size;
674 
675 	/* Matches barrier in axienet_start_xmit */
676 	smp_mb();
677 
678 	netif_wake_queue(ndev);
679 }
680 
681 /**
682  * axienet_check_tx_bd_space - Checks if a BD/group of BDs are currently busy
683  * @lp:		Pointer to the axienet_local structure
684  * @num_frag:	The number of BDs to check for
685  *
686  * Return: 0, on success
687  *	    NETDEV_TX_BUSY, if any of the descriptors are not free
688  *
689  * This function is invoked before BDs are allocated and transmission starts.
690  * This function returns 0 if a BD or group of BDs can be allocated for
691  * transmission. If the BD or any of the BDs are not free the function
692  * returns a busy status. This is invoked from axienet_start_xmit.
693  */
694 static inline int axienet_check_tx_bd_space(struct axienet_local *lp,
695 					    int num_frag)
696 {
697 	struct axidma_bd *cur_p;
698 	cur_p = &lp->tx_bd_v[(lp->tx_bd_tail + num_frag) % lp->tx_bd_num];
699 	if (cur_p->status & XAXIDMA_BD_STS_ALL_MASK)
700 		return NETDEV_TX_BUSY;
701 	return 0;
702 }
703 
704 /**
705  * axienet_start_xmit - Starts the transmission.
706  * @skb:	sk_buff pointer that contains data to be Txed.
707  * @ndev:	Pointer to net_device structure.
708  *
709  * Return: NETDEV_TX_OK, on success
710  *	    NETDEV_TX_BUSY, if any of the descriptors are not free
711  *
712  * This function is invoked from upper layers to initiate transmission. The
713  * function uses the next available free BDs and populates their fields to
714  * start the transmission. Additionally if checksum offloading is supported,
715  * it populates AXI Stream Control fields with appropriate values.
716  */
717 static netdev_tx_t
718 axienet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
719 {
720 	u32 ii;
721 	u32 num_frag;
722 	u32 csum_start_off;
723 	u32 csum_index_off;
724 	skb_frag_t *frag;
725 	dma_addr_t tail_p, phys;
726 	struct axienet_local *lp = netdev_priv(ndev);
727 	struct axidma_bd *cur_p;
728 	u32 orig_tail_ptr = lp->tx_bd_tail;
729 
730 	num_frag = skb_shinfo(skb)->nr_frags;
731 	cur_p = &lp->tx_bd_v[lp->tx_bd_tail];
732 
733 	if (axienet_check_tx_bd_space(lp, num_frag)) {
734 		if (netif_queue_stopped(ndev))
735 			return NETDEV_TX_BUSY;
736 
737 		netif_stop_queue(ndev);
738 
739 		/* Matches barrier in axienet_start_xmit_done */
740 		smp_mb();
741 
742 		/* Space might have just been freed - check again */
743 		if (axienet_check_tx_bd_space(lp, num_frag))
744 			return NETDEV_TX_BUSY;
745 
746 		netif_wake_queue(ndev);
747 	}
748 
749 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
750 		if (lp->features & XAE_FEATURE_FULL_TX_CSUM) {
751 			/* Tx Full Checksum Offload Enabled */
752 			cur_p->app0 |= 2;
753 		} else if (lp->features & XAE_FEATURE_PARTIAL_RX_CSUM) {
754 			csum_start_off = skb_transport_offset(skb);
755 			csum_index_off = csum_start_off + skb->csum_offset;
756 			/* Tx Partial Checksum Offload Enabled */
757 			cur_p->app0 |= 1;
758 			cur_p->app1 = (csum_start_off << 16) | csum_index_off;
759 		}
760 	} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
761 		cur_p->app0 |= 2; /* Tx Full Checksum Offload Enabled */
762 	}
763 
764 	phys = dma_map_single(ndev->dev.parent, skb->data,
765 			      skb_headlen(skb), DMA_TO_DEVICE);
766 	if (unlikely(dma_mapping_error(ndev->dev.parent, phys))) {
767 		if (net_ratelimit())
768 			netdev_err(ndev, "TX DMA mapping error\n");
769 		ndev->stats.tx_dropped++;
770 		return NETDEV_TX_OK;
771 	}
772 	desc_set_phys_addr(lp, phys, cur_p);
773 	cur_p->cntrl = skb_headlen(skb) | XAXIDMA_BD_CTRL_TXSOF_MASK;
774 
775 	for (ii = 0; ii < num_frag; ii++) {
776 		if (++lp->tx_bd_tail >= lp->tx_bd_num)
777 			lp->tx_bd_tail = 0;
778 		cur_p = &lp->tx_bd_v[lp->tx_bd_tail];
779 		frag = &skb_shinfo(skb)->frags[ii];
780 		phys = dma_map_single(ndev->dev.parent,
781 				      skb_frag_address(frag),
782 				      skb_frag_size(frag),
783 				      DMA_TO_DEVICE);
784 		if (unlikely(dma_mapping_error(ndev->dev.parent, phys))) {
785 			if (net_ratelimit())
786 				netdev_err(ndev, "TX DMA mapping error\n");
787 			ndev->stats.tx_dropped++;
788 			axienet_free_tx_chain(ndev, orig_tail_ptr, ii + 1,
789 					      NULL);
790 			lp->tx_bd_tail = orig_tail_ptr;
791 
792 			return NETDEV_TX_OK;
793 		}
794 		desc_set_phys_addr(lp, phys, cur_p);
795 		cur_p->cntrl = skb_frag_size(frag);
796 	}
797 
798 	cur_p->cntrl |= XAXIDMA_BD_CTRL_TXEOF_MASK;
799 	cur_p->skb = skb;
800 
801 	tail_p = lp->tx_bd_p + sizeof(*lp->tx_bd_v) * lp->tx_bd_tail;
802 	/* Start the transfer */
803 	axienet_dma_out_addr(lp, XAXIDMA_TX_TDESC_OFFSET, tail_p);
804 	if (++lp->tx_bd_tail >= lp->tx_bd_num)
805 		lp->tx_bd_tail = 0;
806 
807 	return NETDEV_TX_OK;
808 }
809 
810 /**
811  * axienet_recv - Is called from Axi DMA Rx Isr to complete the received
812  *		  BD processing.
813  * @ndev:	Pointer to net_device structure.
814  *
815  * This function is invoked from the Axi DMA Rx isr to process the Rx BDs. It
816  * does minimal processing and invokes "netif_rx" to complete further
817  * processing.
818  */
819 static void axienet_recv(struct net_device *ndev)
820 {
821 	u32 length;
822 	u32 csumstatus;
823 	u32 size = 0;
824 	u32 packets = 0;
825 	dma_addr_t tail_p = 0;
826 	struct axienet_local *lp = netdev_priv(ndev);
827 	struct sk_buff *skb, *new_skb;
828 	struct axidma_bd *cur_p;
829 
830 	cur_p = &lp->rx_bd_v[lp->rx_bd_ci];
831 
832 	while ((cur_p->status & XAXIDMA_BD_STS_COMPLETE_MASK)) {
833 		dma_addr_t phys;
834 
835 		tail_p = lp->rx_bd_p + sizeof(*lp->rx_bd_v) * lp->rx_bd_ci;
836 
837 		phys = desc_get_phys_addr(lp, cur_p);
838 		dma_unmap_single(ndev->dev.parent, phys, lp->max_frm_size,
839 				 DMA_FROM_DEVICE);
840 
841 		skb = cur_p->skb;
842 		cur_p->skb = NULL;
843 		length = cur_p->app4 & 0x0000FFFF;
844 
845 		skb_put(skb, length);
846 		skb->protocol = eth_type_trans(skb, ndev);
847 		/*skb_checksum_none_assert(skb);*/
848 		skb->ip_summed = CHECKSUM_NONE;
849 
850 		/* if we're doing Rx csum offload, set it up */
851 		if (lp->features & XAE_FEATURE_FULL_RX_CSUM) {
852 			csumstatus = (cur_p->app2 &
853 				      XAE_FULL_CSUM_STATUS_MASK) >> 3;
854 			if ((csumstatus == XAE_IP_TCP_CSUM_VALIDATED) ||
855 			    (csumstatus == XAE_IP_UDP_CSUM_VALIDATED)) {
856 				skb->ip_summed = CHECKSUM_UNNECESSARY;
857 			}
858 		} else if ((lp->features & XAE_FEATURE_PARTIAL_RX_CSUM) != 0 &&
859 			   skb->protocol == htons(ETH_P_IP) &&
860 			   skb->len > 64) {
861 			skb->csum = be32_to_cpu(cur_p->app3 & 0xFFFF);
862 			skb->ip_summed = CHECKSUM_COMPLETE;
863 		}
864 
865 		netif_rx(skb);
866 
867 		size += length;
868 		packets++;
869 
870 		new_skb = netdev_alloc_skb_ip_align(ndev, lp->max_frm_size);
871 		if (!new_skb)
872 			return;
873 
874 		phys = dma_map_single(ndev->dev.parent, new_skb->data,
875 				      lp->max_frm_size,
876 				      DMA_FROM_DEVICE);
877 		if (unlikely(dma_mapping_error(ndev->dev.parent, phys))) {
878 			if (net_ratelimit())
879 				netdev_err(ndev, "RX DMA mapping error\n");
880 			dev_kfree_skb(new_skb);
881 			return;
882 		}
883 		desc_set_phys_addr(lp, phys, cur_p);
884 
885 		cur_p->cntrl = lp->max_frm_size;
886 		cur_p->status = 0;
887 		cur_p->skb = new_skb;
888 
889 		if (++lp->rx_bd_ci >= lp->rx_bd_num)
890 			lp->rx_bd_ci = 0;
891 		cur_p = &lp->rx_bd_v[lp->rx_bd_ci];
892 	}
893 
894 	ndev->stats.rx_packets += packets;
895 	ndev->stats.rx_bytes += size;
896 
897 	if (tail_p)
898 		axienet_dma_out_addr(lp, XAXIDMA_RX_TDESC_OFFSET, tail_p);
899 }
900 
901 /**
902  * axienet_tx_irq - Tx Done Isr.
903  * @irq:	irq number
904  * @_ndev:	net_device pointer
905  *
906  * Return: IRQ_HANDLED if device generated a TX interrupt, IRQ_NONE otherwise.
907  *
908  * This is the Axi DMA Tx done Isr. It invokes "axienet_start_xmit_done"
909  * to complete the BD processing.
910  */
911 static irqreturn_t axienet_tx_irq(int irq, void *_ndev)
912 {
913 	u32 cr;
914 	unsigned int status;
915 	struct net_device *ndev = _ndev;
916 	struct axienet_local *lp = netdev_priv(ndev);
917 
918 	status = axienet_dma_in32(lp, XAXIDMA_TX_SR_OFFSET);
919 	if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
920 		axienet_dma_out32(lp, XAXIDMA_TX_SR_OFFSET, status);
921 		axienet_start_xmit_done(lp->ndev);
922 		goto out;
923 	}
924 	if (!(status & XAXIDMA_IRQ_ALL_MASK))
925 		return IRQ_NONE;
926 	if (status & XAXIDMA_IRQ_ERROR_MASK) {
927 		dev_err(&ndev->dev, "DMA Tx error 0x%x\n", status);
928 		dev_err(&ndev->dev, "Current BD is at: 0x%x%08x\n",
929 			(lp->tx_bd_v[lp->tx_bd_ci]).phys_msb,
930 			(lp->tx_bd_v[lp->tx_bd_ci]).phys);
931 
932 		cr = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
933 		/* Disable coalesce, delay timer and error interrupts */
934 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
935 		/* Write to the Tx channel control register */
936 		axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET, cr);
937 
938 		cr = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
939 		/* Disable coalesce, delay timer and error interrupts */
940 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
941 		/* Write to the Rx channel control register */
942 		axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, cr);
943 
944 		schedule_work(&lp->dma_err_task);
945 		axienet_dma_out32(lp, XAXIDMA_TX_SR_OFFSET, status);
946 	}
947 out:
948 	return IRQ_HANDLED;
949 }
950 
951 /**
952  * axienet_rx_irq - Rx Isr.
953  * @irq:	irq number
954  * @_ndev:	net_device pointer
955  *
956  * Return: IRQ_HANDLED if device generated a RX interrupt, IRQ_NONE otherwise.
957  *
958  * This is the Axi DMA Rx Isr. It invokes "axienet_recv" to complete the BD
959  * processing.
960  */
961 static irqreturn_t axienet_rx_irq(int irq, void *_ndev)
962 {
963 	u32 cr;
964 	unsigned int status;
965 	struct net_device *ndev = _ndev;
966 	struct axienet_local *lp = netdev_priv(ndev);
967 
968 	status = axienet_dma_in32(lp, XAXIDMA_RX_SR_OFFSET);
969 	if (status & (XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_DELAY_MASK)) {
970 		axienet_dma_out32(lp, XAXIDMA_RX_SR_OFFSET, status);
971 		axienet_recv(lp->ndev);
972 		goto out;
973 	}
974 	if (!(status & XAXIDMA_IRQ_ALL_MASK))
975 		return IRQ_NONE;
976 	if (status & XAXIDMA_IRQ_ERROR_MASK) {
977 		dev_err(&ndev->dev, "DMA Rx error 0x%x\n", status);
978 		dev_err(&ndev->dev, "Current BD is at: 0x%x%08x\n",
979 			(lp->rx_bd_v[lp->rx_bd_ci]).phys_msb,
980 			(lp->rx_bd_v[lp->rx_bd_ci]).phys);
981 
982 		cr = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
983 		/* Disable coalesce, delay timer and error interrupts */
984 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
985 		/* Finally write to the Tx channel control register */
986 		axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET, cr);
987 
988 		cr = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
989 		/* Disable coalesce, delay timer and error interrupts */
990 		cr &= (~XAXIDMA_IRQ_ALL_MASK);
991 		/* write to the Rx channel control register */
992 		axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, cr);
993 
994 		schedule_work(&lp->dma_err_task);
995 		axienet_dma_out32(lp, XAXIDMA_RX_SR_OFFSET, status);
996 	}
997 out:
998 	return IRQ_HANDLED;
999 }
1000 
1001 /**
1002  * axienet_eth_irq - Ethernet core Isr.
1003  * @irq:	irq number
1004  * @_ndev:	net_device pointer
1005  *
1006  * Return: IRQ_HANDLED if device generated a core interrupt, IRQ_NONE otherwise.
1007  *
1008  * Handle miscellaneous conditions indicated by Ethernet core IRQ.
1009  */
1010 static irqreturn_t axienet_eth_irq(int irq, void *_ndev)
1011 {
1012 	struct net_device *ndev = _ndev;
1013 	struct axienet_local *lp = netdev_priv(ndev);
1014 	unsigned int pending;
1015 
1016 	pending = axienet_ior(lp, XAE_IP_OFFSET);
1017 	if (!pending)
1018 		return IRQ_NONE;
1019 
1020 	if (pending & XAE_INT_RXFIFOOVR_MASK)
1021 		ndev->stats.rx_missed_errors++;
1022 
1023 	if (pending & XAE_INT_RXRJECT_MASK)
1024 		ndev->stats.rx_frame_errors++;
1025 
1026 	axienet_iow(lp, XAE_IS_OFFSET, pending);
1027 	return IRQ_HANDLED;
1028 }
1029 
1030 static void axienet_dma_err_handler(struct work_struct *work);
1031 
1032 /**
1033  * axienet_open - Driver open routine.
1034  * @ndev:	Pointer to net_device structure
1035  *
1036  * Return: 0, on success.
1037  *	    non-zero error value on failure
1038  *
1039  * This is the driver open routine. It calls phylink_start to start the
1040  * PHY device.
1041  * It also allocates interrupt service routines, enables the interrupt lines
1042  * and ISR handling. Axi Ethernet core is reset through Axi DMA core. Buffer
1043  * descriptors are initialized.
1044  */
1045 static int axienet_open(struct net_device *ndev)
1046 {
1047 	int ret;
1048 	struct axienet_local *lp = netdev_priv(ndev);
1049 
1050 	dev_dbg(&ndev->dev, "axienet_open()\n");
1051 
1052 	/* When we do an Axi Ethernet reset, it resets the complete core
1053 	 * including the MDIO. MDIO must be disabled before resetting.
1054 	 * Hold MDIO bus lock to avoid MDIO accesses during the reset.
1055 	 */
1056 	mutex_lock(&lp->mii_bus->mdio_lock);
1057 	ret = axienet_device_reset(ndev);
1058 	mutex_unlock(&lp->mii_bus->mdio_lock);
1059 
1060 	ret = phylink_of_phy_connect(lp->phylink, lp->dev->of_node, 0);
1061 	if (ret) {
1062 		dev_err(lp->dev, "phylink_of_phy_connect() failed: %d\n", ret);
1063 		return ret;
1064 	}
1065 
1066 	phylink_start(lp->phylink);
1067 
1068 	/* Enable worker thread for Axi DMA error handling */
1069 	INIT_WORK(&lp->dma_err_task, axienet_dma_err_handler);
1070 
1071 	/* Enable interrupts for Axi DMA Tx */
1072 	ret = request_irq(lp->tx_irq, axienet_tx_irq, IRQF_SHARED,
1073 			  ndev->name, ndev);
1074 	if (ret)
1075 		goto err_tx_irq;
1076 	/* Enable interrupts for Axi DMA Rx */
1077 	ret = request_irq(lp->rx_irq, axienet_rx_irq, IRQF_SHARED,
1078 			  ndev->name, ndev);
1079 	if (ret)
1080 		goto err_rx_irq;
1081 	/* Enable interrupts for Axi Ethernet core (if defined) */
1082 	if (lp->eth_irq > 0) {
1083 		ret = request_irq(lp->eth_irq, axienet_eth_irq, IRQF_SHARED,
1084 				  ndev->name, ndev);
1085 		if (ret)
1086 			goto err_eth_irq;
1087 	}
1088 
1089 	return 0;
1090 
1091 err_eth_irq:
1092 	free_irq(lp->rx_irq, ndev);
1093 err_rx_irq:
1094 	free_irq(lp->tx_irq, ndev);
1095 err_tx_irq:
1096 	phylink_stop(lp->phylink);
1097 	phylink_disconnect_phy(lp->phylink);
1098 	cancel_work_sync(&lp->dma_err_task);
1099 	dev_err(lp->dev, "request_irq() failed\n");
1100 	return ret;
1101 }
1102 
1103 /**
1104  * axienet_stop - Driver stop routine.
1105  * @ndev:	Pointer to net_device structure
1106  *
1107  * Return: 0, on success.
1108  *
1109  * This is the driver stop routine. It calls phylink_disconnect to stop the PHY
1110  * device. It also removes the interrupt handlers and disables the interrupts.
1111  * The Axi DMA Tx/Rx BDs are released.
1112  */
1113 static int axienet_stop(struct net_device *ndev)
1114 {
1115 	u32 cr, sr;
1116 	int count;
1117 	struct axienet_local *lp = netdev_priv(ndev);
1118 
1119 	dev_dbg(&ndev->dev, "axienet_close()\n");
1120 
1121 	phylink_stop(lp->phylink);
1122 	phylink_disconnect_phy(lp->phylink);
1123 
1124 	axienet_setoptions(ndev, lp->options &
1125 			   ~(XAE_OPTION_TXEN | XAE_OPTION_RXEN));
1126 
1127 	cr = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
1128 	cr &= ~(XAXIDMA_CR_RUNSTOP_MASK | XAXIDMA_IRQ_ALL_MASK);
1129 	axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, cr);
1130 
1131 	cr = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
1132 	cr &= ~(XAXIDMA_CR_RUNSTOP_MASK | XAXIDMA_IRQ_ALL_MASK);
1133 	axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET, cr);
1134 
1135 	axienet_iow(lp, XAE_IE_OFFSET, 0);
1136 
1137 	/* Give DMAs a chance to halt gracefully */
1138 	sr = axienet_dma_in32(lp, XAXIDMA_RX_SR_OFFSET);
1139 	for (count = 0; !(sr & XAXIDMA_SR_HALT_MASK) && count < 5; ++count) {
1140 		msleep(20);
1141 		sr = axienet_dma_in32(lp, XAXIDMA_RX_SR_OFFSET);
1142 	}
1143 
1144 	sr = axienet_dma_in32(lp, XAXIDMA_TX_SR_OFFSET);
1145 	for (count = 0; !(sr & XAXIDMA_SR_HALT_MASK) && count < 5; ++count) {
1146 		msleep(20);
1147 		sr = axienet_dma_in32(lp, XAXIDMA_TX_SR_OFFSET);
1148 	}
1149 
1150 	/* Do a reset to ensure DMA is really stopped */
1151 	mutex_lock(&lp->mii_bus->mdio_lock);
1152 	__axienet_device_reset(lp);
1153 	mutex_unlock(&lp->mii_bus->mdio_lock);
1154 
1155 	cancel_work_sync(&lp->dma_err_task);
1156 
1157 	if (lp->eth_irq > 0)
1158 		free_irq(lp->eth_irq, ndev);
1159 	free_irq(lp->tx_irq, ndev);
1160 	free_irq(lp->rx_irq, ndev);
1161 
1162 	axienet_dma_bd_release(ndev);
1163 	return 0;
1164 }
1165 
1166 /**
1167  * axienet_change_mtu - Driver change mtu routine.
1168  * @ndev:	Pointer to net_device structure
1169  * @new_mtu:	New mtu value to be applied
1170  *
1171  * Return: Always returns 0 (success).
1172  *
1173  * This is the change mtu driver routine. It checks if the Axi Ethernet
1174  * hardware supports jumbo frames before changing the mtu. This can be
1175  * called only when the device is not up.
1176  */
1177 static int axienet_change_mtu(struct net_device *ndev, int new_mtu)
1178 {
1179 	struct axienet_local *lp = netdev_priv(ndev);
1180 
1181 	if (netif_running(ndev))
1182 		return -EBUSY;
1183 
1184 	if ((new_mtu + VLAN_ETH_HLEN +
1185 		XAE_TRL_SIZE) > lp->rxmem)
1186 		return -EINVAL;
1187 
1188 	ndev->mtu = new_mtu;
1189 
1190 	return 0;
1191 }
1192 
1193 #ifdef CONFIG_NET_POLL_CONTROLLER
1194 /**
1195  * axienet_poll_controller - Axi Ethernet poll mechanism.
1196  * @ndev:	Pointer to net_device structure
1197  *
1198  * This implements Rx/Tx ISR poll mechanisms. The interrupts are disabled prior
1199  * to polling the ISRs and are enabled back after the polling is done.
1200  */
1201 static void axienet_poll_controller(struct net_device *ndev)
1202 {
1203 	struct axienet_local *lp = netdev_priv(ndev);
1204 	disable_irq(lp->tx_irq);
1205 	disable_irq(lp->rx_irq);
1206 	axienet_rx_irq(lp->tx_irq, ndev);
1207 	axienet_tx_irq(lp->rx_irq, ndev);
1208 	enable_irq(lp->tx_irq);
1209 	enable_irq(lp->rx_irq);
1210 }
1211 #endif
1212 
1213 static int axienet_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1214 {
1215 	struct axienet_local *lp = netdev_priv(dev);
1216 
1217 	if (!netif_running(dev))
1218 		return -EINVAL;
1219 
1220 	return phylink_mii_ioctl(lp->phylink, rq, cmd);
1221 }
1222 
1223 static const struct net_device_ops axienet_netdev_ops = {
1224 	.ndo_open = axienet_open,
1225 	.ndo_stop = axienet_stop,
1226 	.ndo_start_xmit = axienet_start_xmit,
1227 	.ndo_change_mtu	= axienet_change_mtu,
1228 	.ndo_set_mac_address = netdev_set_mac_address,
1229 	.ndo_validate_addr = eth_validate_addr,
1230 	.ndo_do_ioctl = axienet_ioctl,
1231 	.ndo_set_rx_mode = axienet_set_multicast_list,
1232 #ifdef CONFIG_NET_POLL_CONTROLLER
1233 	.ndo_poll_controller = axienet_poll_controller,
1234 #endif
1235 };
1236 
1237 /**
1238  * axienet_ethtools_get_drvinfo - Get various Axi Ethernet driver information.
1239  * @ndev:	Pointer to net_device structure
1240  * @ed:		Pointer to ethtool_drvinfo structure
1241  *
1242  * This implements ethtool command for getting the driver information.
1243  * Issue "ethtool -i ethX" under linux prompt to execute this function.
1244  */
1245 static void axienet_ethtools_get_drvinfo(struct net_device *ndev,
1246 					 struct ethtool_drvinfo *ed)
1247 {
1248 	strlcpy(ed->driver, DRIVER_NAME, sizeof(ed->driver));
1249 	strlcpy(ed->version, DRIVER_VERSION, sizeof(ed->version));
1250 }
1251 
1252 /**
1253  * axienet_ethtools_get_regs_len - Get the total regs length present in the
1254  *				   AxiEthernet core.
1255  * @ndev:	Pointer to net_device structure
1256  *
1257  * This implements ethtool command for getting the total register length
1258  * information.
1259  *
1260  * Return: the total regs length
1261  */
1262 static int axienet_ethtools_get_regs_len(struct net_device *ndev)
1263 {
1264 	return sizeof(u32) * AXIENET_REGS_N;
1265 }
1266 
1267 /**
1268  * axienet_ethtools_get_regs - Dump the contents of all registers present
1269  *			       in AxiEthernet core.
1270  * @ndev:	Pointer to net_device structure
1271  * @regs:	Pointer to ethtool_regs structure
1272  * @ret:	Void pointer used to return the contents of the registers.
1273  *
1274  * This implements ethtool command for getting the Axi Ethernet register dump.
1275  * Issue "ethtool -d ethX" to execute this function.
1276  */
1277 static void axienet_ethtools_get_regs(struct net_device *ndev,
1278 				      struct ethtool_regs *regs, void *ret)
1279 {
1280 	u32 *data = (u32 *) ret;
1281 	size_t len = sizeof(u32) * AXIENET_REGS_N;
1282 	struct axienet_local *lp = netdev_priv(ndev);
1283 
1284 	regs->version = 0;
1285 	regs->len = len;
1286 
1287 	memset(data, 0, len);
1288 	data[0] = axienet_ior(lp, XAE_RAF_OFFSET);
1289 	data[1] = axienet_ior(lp, XAE_TPF_OFFSET);
1290 	data[2] = axienet_ior(lp, XAE_IFGP_OFFSET);
1291 	data[3] = axienet_ior(lp, XAE_IS_OFFSET);
1292 	data[4] = axienet_ior(lp, XAE_IP_OFFSET);
1293 	data[5] = axienet_ior(lp, XAE_IE_OFFSET);
1294 	data[6] = axienet_ior(lp, XAE_TTAG_OFFSET);
1295 	data[7] = axienet_ior(lp, XAE_RTAG_OFFSET);
1296 	data[8] = axienet_ior(lp, XAE_UAWL_OFFSET);
1297 	data[9] = axienet_ior(lp, XAE_UAWU_OFFSET);
1298 	data[10] = axienet_ior(lp, XAE_TPID0_OFFSET);
1299 	data[11] = axienet_ior(lp, XAE_TPID1_OFFSET);
1300 	data[12] = axienet_ior(lp, XAE_PPST_OFFSET);
1301 	data[13] = axienet_ior(lp, XAE_RCW0_OFFSET);
1302 	data[14] = axienet_ior(lp, XAE_RCW1_OFFSET);
1303 	data[15] = axienet_ior(lp, XAE_TC_OFFSET);
1304 	data[16] = axienet_ior(lp, XAE_FCC_OFFSET);
1305 	data[17] = axienet_ior(lp, XAE_EMMC_OFFSET);
1306 	data[18] = axienet_ior(lp, XAE_PHYC_OFFSET);
1307 	data[19] = axienet_ior(lp, XAE_MDIO_MC_OFFSET);
1308 	data[20] = axienet_ior(lp, XAE_MDIO_MCR_OFFSET);
1309 	data[21] = axienet_ior(lp, XAE_MDIO_MWD_OFFSET);
1310 	data[22] = axienet_ior(lp, XAE_MDIO_MRD_OFFSET);
1311 	data[27] = axienet_ior(lp, XAE_UAW0_OFFSET);
1312 	data[28] = axienet_ior(lp, XAE_UAW1_OFFSET);
1313 	data[29] = axienet_ior(lp, XAE_FMI_OFFSET);
1314 	data[30] = axienet_ior(lp, XAE_AF0_OFFSET);
1315 	data[31] = axienet_ior(lp, XAE_AF1_OFFSET);
1316 	data[32] = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
1317 	data[33] = axienet_dma_in32(lp, XAXIDMA_TX_SR_OFFSET);
1318 	data[34] = axienet_dma_in32(lp, XAXIDMA_TX_CDESC_OFFSET);
1319 	data[35] = axienet_dma_in32(lp, XAXIDMA_TX_TDESC_OFFSET);
1320 	data[36] = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
1321 	data[37] = axienet_dma_in32(lp, XAXIDMA_RX_SR_OFFSET);
1322 	data[38] = axienet_dma_in32(lp, XAXIDMA_RX_CDESC_OFFSET);
1323 	data[39] = axienet_dma_in32(lp, XAXIDMA_RX_TDESC_OFFSET);
1324 }
1325 
1326 static void axienet_ethtools_get_ringparam(struct net_device *ndev,
1327 					   struct ethtool_ringparam *ering)
1328 {
1329 	struct axienet_local *lp = netdev_priv(ndev);
1330 
1331 	ering->rx_max_pending = RX_BD_NUM_MAX;
1332 	ering->rx_mini_max_pending = 0;
1333 	ering->rx_jumbo_max_pending = 0;
1334 	ering->tx_max_pending = TX_BD_NUM_MAX;
1335 	ering->rx_pending = lp->rx_bd_num;
1336 	ering->rx_mini_pending = 0;
1337 	ering->rx_jumbo_pending = 0;
1338 	ering->tx_pending = lp->tx_bd_num;
1339 }
1340 
1341 static int axienet_ethtools_set_ringparam(struct net_device *ndev,
1342 					  struct ethtool_ringparam *ering)
1343 {
1344 	struct axienet_local *lp = netdev_priv(ndev);
1345 
1346 	if (ering->rx_pending > RX_BD_NUM_MAX ||
1347 	    ering->rx_mini_pending ||
1348 	    ering->rx_jumbo_pending ||
1349 	    ering->rx_pending > TX_BD_NUM_MAX)
1350 		return -EINVAL;
1351 
1352 	if (netif_running(ndev))
1353 		return -EBUSY;
1354 
1355 	lp->rx_bd_num = ering->rx_pending;
1356 	lp->tx_bd_num = ering->tx_pending;
1357 	return 0;
1358 }
1359 
1360 /**
1361  * axienet_ethtools_get_pauseparam - Get the pause parameter setting for
1362  *				     Tx and Rx paths.
1363  * @ndev:	Pointer to net_device structure
1364  * @epauseparm:	Pointer to ethtool_pauseparam structure.
1365  *
1366  * This implements ethtool command for getting axi ethernet pause frame
1367  * setting. Issue "ethtool -a ethX" to execute this function.
1368  */
1369 static void
1370 axienet_ethtools_get_pauseparam(struct net_device *ndev,
1371 				struct ethtool_pauseparam *epauseparm)
1372 {
1373 	struct axienet_local *lp = netdev_priv(ndev);
1374 
1375 	phylink_ethtool_get_pauseparam(lp->phylink, epauseparm);
1376 }
1377 
1378 /**
1379  * axienet_ethtools_set_pauseparam - Set device pause parameter(flow control)
1380  *				     settings.
1381  * @ndev:	Pointer to net_device structure
1382  * @epauseparm:Pointer to ethtool_pauseparam structure
1383  *
1384  * This implements ethtool command for enabling flow control on Rx and Tx
1385  * paths. Issue "ethtool -A ethX tx on|off" under linux prompt to execute this
1386  * function.
1387  *
1388  * Return: 0 on success, -EFAULT if device is running
1389  */
1390 static int
1391 axienet_ethtools_set_pauseparam(struct net_device *ndev,
1392 				struct ethtool_pauseparam *epauseparm)
1393 {
1394 	struct axienet_local *lp = netdev_priv(ndev);
1395 
1396 	return phylink_ethtool_set_pauseparam(lp->phylink, epauseparm);
1397 }
1398 
1399 /**
1400  * axienet_ethtools_get_coalesce - Get DMA interrupt coalescing count.
1401  * @ndev:	Pointer to net_device structure
1402  * @ecoalesce:	Pointer to ethtool_coalesce structure
1403  *
1404  * This implements ethtool command for getting the DMA interrupt coalescing
1405  * count on Tx and Rx paths. Issue "ethtool -c ethX" under linux prompt to
1406  * execute this function.
1407  *
1408  * Return: 0 always
1409  */
1410 static int axienet_ethtools_get_coalesce(struct net_device *ndev,
1411 					 struct ethtool_coalesce *ecoalesce)
1412 {
1413 	u32 regval = 0;
1414 	struct axienet_local *lp = netdev_priv(ndev);
1415 	regval = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
1416 	ecoalesce->rx_max_coalesced_frames = (regval & XAXIDMA_COALESCE_MASK)
1417 					     >> XAXIDMA_COALESCE_SHIFT;
1418 	regval = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
1419 	ecoalesce->tx_max_coalesced_frames = (regval & XAXIDMA_COALESCE_MASK)
1420 					     >> XAXIDMA_COALESCE_SHIFT;
1421 	return 0;
1422 }
1423 
1424 /**
1425  * axienet_ethtools_set_coalesce - Set DMA interrupt coalescing count.
1426  * @ndev:	Pointer to net_device structure
1427  * @ecoalesce:	Pointer to ethtool_coalesce structure
1428  *
1429  * This implements ethtool command for setting the DMA interrupt coalescing
1430  * count on Tx and Rx paths. Issue "ethtool -C ethX rx-frames 5" under linux
1431  * prompt to execute this function.
1432  *
1433  * Return: 0, on success, Non-zero error value on failure.
1434  */
1435 static int axienet_ethtools_set_coalesce(struct net_device *ndev,
1436 					 struct ethtool_coalesce *ecoalesce)
1437 {
1438 	struct axienet_local *lp = netdev_priv(ndev);
1439 
1440 	if (netif_running(ndev)) {
1441 		netdev_err(ndev,
1442 			   "Please stop netif before applying configuration\n");
1443 		return -EFAULT;
1444 	}
1445 
1446 	if (ecoalesce->rx_max_coalesced_frames)
1447 		lp->coalesce_count_rx = ecoalesce->rx_max_coalesced_frames;
1448 	if (ecoalesce->tx_max_coalesced_frames)
1449 		lp->coalesce_count_tx = ecoalesce->tx_max_coalesced_frames;
1450 
1451 	return 0;
1452 }
1453 
1454 static int
1455 axienet_ethtools_get_link_ksettings(struct net_device *ndev,
1456 				    struct ethtool_link_ksettings *cmd)
1457 {
1458 	struct axienet_local *lp = netdev_priv(ndev);
1459 
1460 	return phylink_ethtool_ksettings_get(lp->phylink, cmd);
1461 }
1462 
1463 static int
1464 axienet_ethtools_set_link_ksettings(struct net_device *ndev,
1465 				    const struct ethtool_link_ksettings *cmd)
1466 {
1467 	struct axienet_local *lp = netdev_priv(ndev);
1468 
1469 	return phylink_ethtool_ksettings_set(lp->phylink, cmd);
1470 }
1471 
1472 static const struct ethtool_ops axienet_ethtool_ops = {
1473 	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES,
1474 	.get_drvinfo    = axienet_ethtools_get_drvinfo,
1475 	.get_regs_len   = axienet_ethtools_get_regs_len,
1476 	.get_regs       = axienet_ethtools_get_regs,
1477 	.get_link       = ethtool_op_get_link,
1478 	.get_ringparam	= axienet_ethtools_get_ringparam,
1479 	.set_ringparam	= axienet_ethtools_set_ringparam,
1480 	.get_pauseparam = axienet_ethtools_get_pauseparam,
1481 	.set_pauseparam = axienet_ethtools_set_pauseparam,
1482 	.get_coalesce   = axienet_ethtools_get_coalesce,
1483 	.set_coalesce   = axienet_ethtools_set_coalesce,
1484 	.get_link_ksettings = axienet_ethtools_get_link_ksettings,
1485 	.set_link_ksettings = axienet_ethtools_set_link_ksettings,
1486 };
1487 
1488 static void axienet_validate(struct phylink_config *config,
1489 			     unsigned long *supported,
1490 			     struct phylink_link_state *state)
1491 {
1492 	struct net_device *ndev = to_net_dev(config->dev);
1493 	struct axienet_local *lp = netdev_priv(ndev);
1494 	__ETHTOOL_DECLARE_LINK_MODE_MASK(mask) = { 0, };
1495 
1496 	/* Only support the mode we are configured for */
1497 	if (state->interface != PHY_INTERFACE_MODE_NA &&
1498 	    state->interface != lp->phy_mode) {
1499 		netdev_warn(ndev, "Cannot use PHY mode %s, supported: %s\n",
1500 			    phy_modes(state->interface),
1501 			    phy_modes(lp->phy_mode));
1502 		bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
1503 		return;
1504 	}
1505 
1506 	phylink_set(mask, Autoneg);
1507 	phylink_set_port_modes(mask);
1508 
1509 	phylink_set(mask, Asym_Pause);
1510 	phylink_set(mask, Pause);
1511 
1512 	switch (state->interface) {
1513 	case PHY_INTERFACE_MODE_NA:
1514 	case PHY_INTERFACE_MODE_1000BASEX:
1515 	case PHY_INTERFACE_MODE_SGMII:
1516 	case PHY_INTERFACE_MODE_GMII:
1517 	case PHY_INTERFACE_MODE_RGMII:
1518 	case PHY_INTERFACE_MODE_RGMII_ID:
1519 	case PHY_INTERFACE_MODE_RGMII_RXID:
1520 	case PHY_INTERFACE_MODE_RGMII_TXID:
1521 		phylink_set(mask, 1000baseX_Full);
1522 		phylink_set(mask, 1000baseT_Full);
1523 		if (state->interface == PHY_INTERFACE_MODE_1000BASEX)
1524 			break;
1525 		fallthrough;
1526 	case PHY_INTERFACE_MODE_MII:
1527 		phylink_set(mask, 100baseT_Full);
1528 		phylink_set(mask, 10baseT_Full);
1529 	default:
1530 		break;
1531 	}
1532 
1533 	bitmap_and(supported, supported, mask,
1534 		   __ETHTOOL_LINK_MODE_MASK_NBITS);
1535 	bitmap_and(state->advertising, state->advertising, mask,
1536 		   __ETHTOOL_LINK_MODE_MASK_NBITS);
1537 }
1538 
1539 static void axienet_mac_pcs_get_state(struct phylink_config *config,
1540 				      struct phylink_link_state *state)
1541 {
1542 	struct net_device *ndev = to_net_dev(config->dev);
1543 	struct axienet_local *lp = netdev_priv(ndev);
1544 
1545 	switch (state->interface) {
1546 	case PHY_INTERFACE_MODE_SGMII:
1547 	case PHY_INTERFACE_MODE_1000BASEX:
1548 		phylink_mii_c22_pcs_get_state(lp->pcs_phy, state);
1549 		break;
1550 	default:
1551 		break;
1552 	}
1553 }
1554 
1555 static void axienet_mac_an_restart(struct phylink_config *config)
1556 {
1557 	struct net_device *ndev = to_net_dev(config->dev);
1558 	struct axienet_local *lp = netdev_priv(ndev);
1559 
1560 	phylink_mii_c22_pcs_an_restart(lp->pcs_phy);
1561 }
1562 
1563 static void axienet_mac_config(struct phylink_config *config, unsigned int mode,
1564 			       const struct phylink_link_state *state)
1565 {
1566 	struct net_device *ndev = to_net_dev(config->dev);
1567 	struct axienet_local *lp = netdev_priv(ndev);
1568 	int ret;
1569 
1570 	switch (state->interface) {
1571 	case PHY_INTERFACE_MODE_SGMII:
1572 	case PHY_INTERFACE_MODE_1000BASEX:
1573 		ret = phylink_mii_c22_pcs_config(lp->pcs_phy, mode,
1574 						 state->interface,
1575 						 state->advertising);
1576 		if (ret < 0)
1577 			netdev_warn(ndev, "Failed to configure PCS: %d\n",
1578 				    ret);
1579 		break;
1580 
1581 	default:
1582 		break;
1583 	}
1584 }
1585 
1586 static void axienet_mac_link_down(struct phylink_config *config,
1587 				  unsigned int mode,
1588 				  phy_interface_t interface)
1589 {
1590 	/* nothing meaningful to do */
1591 }
1592 
1593 static void axienet_mac_link_up(struct phylink_config *config,
1594 				struct phy_device *phy,
1595 				unsigned int mode, phy_interface_t interface,
1596 				int speed, int duplex,
1597 				bool tx_pause, bool rx_pause)
1598 {
1599 	struct net_device *ndev = to_net_dev(config->dev);
1600 	struct axienet_local *lp = netdev_priv(ndev);
1601 	u32 emmc_reg, fcc_reg;
1602 
1603 	emmc_reg = axienet_ior(lp, XAE_EMMC_OFFSET);
1604 	emmc_reg &= ~XAE_EMMC_LINKSPEED_MASK;
1605 
1606 	switch (speed) {
1607 	case SPEED_1000:
1608 		emmc_reg |= XAE_EMMC_LINKSPD_1000;
1609 		break;
1610 	case SPEED_100:
1611 		emmc_reg |= XAE_EMMC_LINKSPD_100;
1612 		break;
1613 	case SPEED_10:
1614 		emmc_reg |= XAE_EMMC_LINKSPD_10;
1615 		break;
1616 	default:
1617 		dev_err(&ndev->dev,
1618 			"Speed other than 10, 100 or 1Gbps is not supported\n");
1619 		break;
1620 	}
1621 
1622 	axienet_iow(lp, XAE_EMMC_OFFSET, emmc_reg);
1623 
1624 	fcc_reg = axienet_ior(lp, XAE_FCC_OFFSET);
1625 	if (tx_pause)
1626 		fcc_reg |= XAE_FCC_FCTX_MASK;
1627 	else
1628 		fcc_reg &= ~XAE_FCC_FCTX_MASK;
1629 	if (rx_pause)
1630 		fcc_reg |= XAE_FCC_FCRX_MASK;
1631 	else
1632 		fcc_reg &= ~XAE_FCC_FCRX_MASK;
1633 	axienet_iow(lp, XAE_FCC_OFFSET, fcc_reg);
1634 }
1635 
1636 static const struct phylink_mac_ops axienet_phylink_ops = {
1637 	.validate = axienet_validate,
1638 	.mac_pcs_get_state = axienet_mac_pcs_get_state,
1639 	.mac_an_restart = axienet_mac_an_restart,
1640 	.mac_config = axienet_mac_config,
1641 	.mac_link_down = axienet_mac_link_down,
1642 	.mac_link_up = axienet_mac_link_up,
1643 };
1644 
1645 /**
1646  * axienet_dma_err_handler - Work queue task for Axi DMA Error
1647  * @work:	pointer to work_struct
1648  *
1649  * Resets the Axi DMA and Axi Ethernet devices, and reconfigures the
1650  * Tx/Rx BDs.
1651  */
1652 static void axienet_dma_err_handler(struct work_struct *work)
1653 {
1654 	u32 axienet_status;
1655 	u32 cr, i;
1656 	struct axienet_local *lp = container_of(work, struct axienet_local,
1657 						dma_err_task);
1658 	struct net_device *ndev = lp->ndev;
1659 	struct axidma_bd *cur_p;
1660 
1661 	axienet_setoptions(ndev, lp->options &
1662 			   ~(XAE_OPTION_TXEN | XAE_OPTION_RXEN));
1663 	/* When we do an Axi Ethernet reset, it resets the complete core
1664 	 * including the MDIO. MDIO must be disabled before resetting.
1665 	 * Hold MDIO bus lock to avoid MDIO accesses during the reset.
1666 	 */
1667 	mutex_lock(&lp->mii_bus->mdio_lock);
1668 	__axienet_device_reset(lp);
1669 	mutex_unlock(&lp->mii_bus->mdio_lock);
1670 
1671 	for (i = 0; i < lp->tx_bd_num; i++) {
1672 		cur_p = &lp->tx_bd_v[i];
1673 		if (cur_p->cntrl) {
1674 			dma_addr_t addr = desc_get_phys_addr(lp, cur_p);
1675 
1676 			dma_unmap_single(ndev->dev.parent, addr,
1677 					 (cur_p->cntrl &
1678 					  XAXIDMA_BD_CTRL_LENGTH_MASK),
1679 					 DMA_TO_DEVICE);
1680 		}
1681 		if (cur_p->skb)
1682 			dev_kfree_skb_irq(cur_p->skb);
1683 		cur_p->phys = 0;
1684 		cur_p->phys_msb = 0;
1685 		cur_p->cntrl = 0;
1686 		cur_p->status = 0;
1687 		cur_p->app0 = 0;
1688 		cur_p->app1 = 0;
1689 		cur_p->app2 = 0;
1690 		cur_p->app3 = 0;
1691 		cur_p->app4 = 0;
1692 		cur_p->skb = NULL;
1693 	}
1694 
1695 	for (i = 0; i < lp->rx_bd_num; i++) {
1696 		cur_p = &lp->rx_bd_v[i];
1697 		cur_p->status = 0;
1698 		cur_p->app0 = 0;
1699 		cur_p->app1 = 0;
1700 		cur_p->app2 = 0;
1701 		cur_p->app3 = 0;
1702 		cur_p->app4 = 0;
1703 	}
1704 
1705 	lp->tx_bd_ci = 0;
1706 	lp->tx_bd_tail = 0;
1707 	lp->rx_bd_ci = 0;
1708 
1709 	/* Start updating the Rx channel control register */
1710 	cr = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
1711 	/* Update the interrupt coalesce count */
1712 	cr = ((cr & ~XAXIDMA_COALESCE_MASK) |
1713 	      (XAXIDMA_DFT_RX_THRESHOLD << XAXIDMA_COALESCE_SHIFT));
1714 	/* Update the delay timer count */
1715 	cr = ((cr & ~XAXIDMA_DELAY_MASK) |
1716 	      (XAXIDMA_DFT_RX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
1717 	/* Enable coalesce, delay timer and error interrupts */
1718 	cr |= XAXIDMA_IRQ_ALL_MASK;
1719 	/* Finally write to the Rx channel control register */
1720 	axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, cr);
1721 
1722 	/* Start updating the Tx channel control register */
1723 	cr = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
1724 	/* Update the interrupt coalesce count */
1725 	cr = (((cr & ~XAXIDMA_COALESCE_MASK)) |
1726 	      (XAXIDMA_DFT_TX_THRESHOLD << XAXIDMA_COALESCE_SHIFT));
1727 	/* Update the delay timer count */
1728 	cr = (((cr & ~XAXIDMA_DELAY_MASK)) |
1729 	      (XAXIDMA_DFT_TX_WAITBOUND << XAXIDMA_DELAY_SHIFT));
1730 	/* Enable coalesce, delay timer and error interrupts */
1731 	cr |= XAXIDMA_IRQ_ALL_MASK;
1732 	/* Finally write to the Tx channel control register */
1733 	axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET, cr);
1734 
1735 	/* Populate the tail pointer and bring the Rx Axi DMA engine out of
1736 	 * halted state. This will make the Rx side ready for reception.
1737 	 */
1738 	axienet_dma_out_addr(lp, XAXIDMA_RX_CDESC_OFFSET, lp->rx_bd_p);
1739 	cr = axienet_dma_in32(lp, XAXIDMA_RX_CR_OFFSET);
1740 	axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET,
1741 			  cr | XAXIDMA_CR_RUNSTOP_MASK);
1742 	axienet_dma_out_addr(lp, XAXIDMA_RX_TDESC_OFFSET, lp->rx_bd_p +
1743 			     (sizeof(*lp->rx_bd_v) * (lp->rx_bd_num - 1)));
1744 
1745 	/* Write to the RS (Run-stop) bit in the Tx channel control register.
1746 	 * Tx channel is now ready to run. But only after we write to the
1747 	 * tail pointer register that the Tx channel will start transmitting
1748 	 */
1749 	axienet_dma_out_addr(lp, XAXIDMA_TX_CDESC_OFFSET, lp->tx_bd_p);
1750 	cr = axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET);
1751 	axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET,
1752 			  cr | XAXIDMA_CR_RUNSTOP_MASK);
1753 
1754 	axienet_status = axienet_ior(lp, XAE_RCW1_OFFSET);
1755 	axienet_status &= ~XAE_RCW1_RX_MASK;
1756 	axienet_iow(lp, XAE_RCW1_OFFSET, axienet_status);
1757 
1758 	axienet_status = axienet_ior(lp, XAE_IP_OFFSET);
1759 	if (axienet_status & XAE_INT_RXRJECT_MASK)
1760 		axienet_iow(lp, XAE_IS_OFFSET, XAE_INT_RXRJECT_MASK);
1761 	axienet_iow(lp, XAE_IE_OFFSET, lp->eth_irq > 0 ?
1762 		    XAE_INT_RECV_ERROR_MASK : 0);
1763 	axienet_iow(lp, XAE_FCC_OFFSET, XAE_FCC_FCRX_MASK);
1764 
1765 	/* Sync default options with HW but leave receiver and
1766 	 * transmitter disabled.
1767 	 */
1768 	axienet_setoptions(ndev, lp->options &
1769 			   ~(XAE_OPTION_TXEN | XAE_OPTION_RXEN));
1770 	axienet_set_mac_address(ndev, NULL);
1771 	axienet_set_multicast_list(ndev);
1772 	axienet_setoptions(ndev, lp->options);
1773 }
1774 
1775 /**
1776  * axienet_probe - Axi Ethernet probe function.
1777  * @pdev:	Pointer to platform device structure.
1778  *
1779  * Return: 0, on success
1780  *	    Non-zero error value on failure.
1781  *
1782  * This is the probe routine for Axi Ethernet driver. This is called before
1783  * any other driver routines are invoked. It allocates and sets up the Ethernet
1784  * device. Parses through device tree and populates fields of
1785  * axienet_local. It registers the Ethernet device.
1786  */
1787 static int axienet_probe(struct platform_device *pdev)
1788 {
1789 	int ret;
1790 	struct device_node *np;
1791 	struct axienet_local *lp;
1792 	struct net_device *ndev;
1793 	const void *mac_addr;
1794 	struct resource *ethres;
1795 	int addr_width = 32;
1796 	u32 value;
1797 
1798 	ndev = alloc_etherdev(sizeof(*lp));
1799 	if (!ndev)
1800 		return -ENOMEM;
1801 
1802 	platform_set_drvdata(pdev, ndev);
1803 
1804 	SET_NETDEV_DEV(ndev, &pdev->dev);
1805 	ndev->flags &= ~IFF_MULTICAST;  /* clear multicast */
1806 	ndev->features = NETIF_F_SG;
1807 	ndev->netdev_ops = &axienet_netdev_ops;
1808 	ndev->ethtool_ops = &axienet_ethtool_ops;
1809 
1810 	/* MTU range: 64 - 9000 */
1811 	ndev->min_mtu = 64;
1812 	ndev->max_mtu = XAE_JUMBO_MTU;
1813 
1814 	lp = netdev_priv(ndev);
1815 	lp->ndev = ndev;
1816 	lp->dev = &pdev->dev;
1817 	lp->options = XAE_OPTION_DEFAULTS;
1818 	lp->rx_bd_num = RX_BD_NUM_DEFAULT;
1819 	lp->tx_bd_num = TX_BD_NUM_DEFAULT;
1820 	/* Map device registers */
1821 	ethres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1822 	lp->regs = devm_ioremap_resource(&pdev->dev, ethres);
1823 	if (IS_ERR(lp->regs)) {
1824 		dev_err(&pdev->dev, "could not map Axi Ethernet regs.\n");
1825 		ret = PTR_ERR(lp->regs);
1826 		goto free_netdev;
1827 	}
1828 	lp->regs_start = ethres->start;
1829 
1830 	/* Setup checksum offload, but default to off if not specified */
1831 	lp->features = 0;
1832 
1833 	ret = of_property_read_u32(pdev->dev.of_node, "xlnx,txcsum", &value);
1834 	if (!ret) {
1835 		switch (value) {
1836 		case 1:
1837 			lp->csum_offload_on_tx_path =
1838 				XAE_FEATURE_PARTIAL_TX_CSUM;
1839 			lp->features |= XAE_FEATURE_PARTIAL_TX_CSUM;
1840 			/* Can checksum TCP/UDP over IPv4. */
1841 			ndev->features |= NETIF_F_IP_CSUM;
1842 			break;
1843 		case 2:
1844 			lp->csum_offload_on_tx_path =
1845 				XAE_FEATURE_FULL_TX_CSUM;
1846 			lp->features |= XAE_FEATURE_FULL_TX_CSUM;
1847 			/* Can checksum TCP/UDP over IPv4. */
1848 			ndev->features |= NETIF_F_IP_CSUM;
1849 			break;
1850 		default:
1851 			lp->csum_offload_on_tx_path = XAE_NO_CSUM_OFFLOAD;
1852 		}
1853 	}
1854 	ret = of_property_read_u32(pdev->dev.of_node, "xlnx,rxcsum", &value);
1855 	if (!ret) {
1856 		switch (value) {
1857 		case 1:
1858 			lp->csum_offload_on_rx_path =
1859 				XAE_FEATURE_PARTIAL_RX_CSUM;
1860 			lp->features |= XAE_FEATURE_PARTIAL_RX_CSUM;
1861 			break;
1862 		case 2:
1863 			lp->csum_offload_on_rx_path =
1864 				XAE_FEATURE_FULL_RX_CSUM;
1865 			lp->features |= XAE_FEATURE_FULL_RX_CSUM;
1866 			break;
1867 		default:
1868 			lp->csum_offload_on_rx_path = XAE_NO_CSUM_OFFLOAD;
1869 		}
1870 	}
1871 	/* For supporting jumbo frames, the Axi Ethernet hardware must have
1872 	 * a larger Rx/Tx Memory. Typically, the size must be large so that
1873 	 * we can enable jumbo option and start supporting jumbo frames.
1874 	 * Here we check for memory allocated for Rx/Tx in the hardware from
1875 	 * the device-tree and accordingly set flags.
1876 	 */
1877 	of_property_read_u32(pdev->dev.of_node, "xlnx,rxmem", &lp->rxmem);
1878 
1879 	/* Start with the proprietary, and broken phy_type */
1880 	ret = of_property_read_u32(pdev->dev.of_node, "xlnx,phy-type", &value);
1881 	if (!ret) {
1882 		netdev_warn(ndev, "Please upgrade your device tree binary blob to use phy-mode");
1883 		switch (value) {
1884 		case XAE_PHY_TYPE_MII:
1885 			lp->phy_mode = PHY_INTERFACE_MODE_MII;
1886 			break;
1887 		case XAE_PHY_TYPE_GMII:
1888 			lp->phy_mode = PHY_INTERFACE_MODE_GMII;
1889 			break;
1890 		case XAE_PHY_TYPE_RGMII_2_0:
1891 			lp->phy_mode = PHY_INTERFACE_MODE_RGMII_ID;
1892 			break;
1893 		case XAE_PHY_TYPE_SGMII:
1894 			lp->phy_mode = PHY_INTERFACE_MODE_SGMII;
1895 			break;
1896 		case XAE_PHY_TYPE_1000BASE_X:
1897 			lp->phy_mode = PHY_INTERFACE_MODE_1000BASEX;
1898 			break;
1899 		default:
1900 			ret = -EINVAL;
1901 			goto free_netdev;
1902 		}
1903 	} else {
1904 		ret = of_get_phy_mode(pdev->dev.of_node, &lp->phy_mode);
1905 		if (ret)
1906 			goto free_netdev;
1907 	}
1908 
1909 	/* Find the DMA node, map the DMA registers, and decode the DMA IRQs */
1910 	np = of_parse_phandle(pdev->dev.of_node, "axistream-connected", 0);
1911 	if (np) {
1912 		struct resource dmares;
1913 
1914 		ret = of_address_to_resource(np, 0, &dmares);
1915 		if (ret) {
1916 			dev_err(&pdev->dev,
1917 				"unable to get DMA resource\n");
1918 			of_node_put(np);
1919 			goto free_netdev;
1920 		}
1921 		lp->dma_regs = devm_ioremap_resource(&pdev->dev,
1922 						     &dmares);
1923 		lp->rx_irq = irq_of_parse_and_map(np, 1);
1924 		lp->tx_irq = irq_of_parse_and_map(np, 0);
1925 		of_node_put(np);
1926 		lp->eth_irq = platform_get_irq_optional(pdev, 0);
1927 	} else {
1928 		/* Check for these resources directly on the Ethernet node. */
1929 		struct resource *res = platform_get_resource(pdev,
1930 							     IORESOURCE_MEM, 1);
1931 		lp->dma_regs = devm_ioremap_resource(&pdev->dev, res);
1932 		lp->rx_irq = platform_get_irq(pdev, 1);
1933 		lp->tx_irq = platform_get_irq(pdev, 0);
1934 		lp->eth_irq = platform_get_irq_optional(pdev, 2);
1935 	}
1936 	if (IS_ERR(lp->dma_regs)) {
1937 		dev_err(&pdev->dev, "could not map DMA regs\n");
1938 		ret = PTR_ERR(lp->dma_regs);
1939 		goto free_netdev;
1940 	}
1941 	if ((lp->rx_irq <= 0) || (lp->tx_irq <= 0)) {
1942 		dev_err(&pdev->dev, "could not determine irqs\n");
1943 		ret = -ENOMEM;
1944 		goto free_netdev;
1945 	}
1946 
1947 	/* Autodetect the need for 64-bit DMA pointers.
1948 	 * When the IP is configured for a bus width bigger than 32 bits,
1949 	 * writing the MSB registers is mandatory, even if they are all 0.
1950 	 * We can detect this case by writing all 1's to one such register
1951 	 * and see if that sticks: when the IP is configured for 32 bits
1952 	 * only, those registers are RES0.
1953 	 * Those MSB registers were introduced in IP v7.1, which we check first.
1954 	 */
1955 	if ((axienet_ior(lp, XAE_ID_OFFSET) >> 24) >= 0x9) {
1956 		void __iomem *desc = lp->dma_regs + XAXIDMA_TX_CDESC_OFFSET + 4;
1957 
1958 		iowrite32(0x0, desc);
1959 		if (ioread32(desc) == 0) {	/* sanity check */
1960 			iowrite32(0xffffffff, desc);
1961 			if (ioread32(desc) > 0) {
1962 				lp->features |= XAE_FEATURE_DMA_64BIT;
1963 				addr_width = 64;
1964 				dev_info(&pdev->dev,
1965 					 "autodetected 64-bit DMA range\n");
1966 			}
1967 			iowrite32(0x0, desc);
1968 		}
1969 	}
1970 
1971 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(addr_width));
1972 	if (ret) {
1973 		dev_err(&pdev->dev, "No suitable DMA available\n");
1974 		goto free_netdev;
1975 	}
1976 
1977 	/* Check for Ethernet core IRQ (optional) */
1978 	if (lp->eth_irq <= 0)
1979 		dev_info(&pdev->dev, "Ethernet core IRQ not defined\n");
1980 
1981 	/* Retrieve the MAC address */
1982 	mac_addr = of_get_mac_address(pdev->dev.of_node);
1983 	if (IS_ERR(mac_addr)) {
1984 		dev_warn(&pdev->dev, "could not find MAC address property: %ld\n",
1985 			 PTR_ERR(mac_addr));
1986 		mac_addr = NULL;
1987 	}
1988 	axienet_set_mac_address(ndev, mac_addr);
1989 
1990 	lp->coalesce_count_rx = XAXIDMA_DFT_RX_THRESHOLD;
1991 	lp->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD;
1992 
1993 	lp->phy_node = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
1994 	if (lp->phy_node) {
1995 		lp->clk = devm_clk_get(&pdev->dev, NULL);
1996 		if (IS_ERR(lp->clk)) {
1997 			dev_warn(&pdev->dev, "Failed to get clock: %ld\n",
1998 				 PTR_ERR(lp->clk));
1999 			lp->clk = NULL;
2000 		} else {
2001 			ret = clk_prepare_enable(lp->clk);
2002 			if (ret) {
2003 				dev_err(&pdev->dev, "Unable to enable clock: %d\n",
2004 					ret);
2005 				goto free_netdev;
2006 			}
2007 		}
2008 
2009 		ret = axienet_mdio_setup(lp);
2010 		if (ret)
2011 			dev_warn(&pdev->dev,
2012 				 "error registering MDIO bus: %d\n", ret);
2013 	}
2014 	if (lp->phy_mode == PHY_INTERFACE_MODE_SGMII ||
2015 	    lp->phy_mode == PHY_INTERFACE_MODE_1000BASEX) {
2016 		if (!lp->phy_node) {
2017 			dev_err(&pdev->dev, "phy-handle required for 1000BaseX/SGMII\n");
2018 			ret = -EINVAL;
2019 			goto free_netdev;
2020 		}
2021 		lp->pcs_phy = of_mdio_find_device(lp->phy_node);
2022 		if (!lp->pcs_phy) {
2023 			ret = -EPROBE_DEFER;
2024 			goto free_netdev;
2025 		}
2026 		lp->phylink_config.pcs_poll = true;
2027 	}
2028 
2029 	lp->phylink_config.dev = &ndev->dev;
2030 	lp->phylink_config.type = PHYLINK_NETDEV;
2031 
2032 	lp->phylink = phylink_create(&lp->phylink_config, pdev->dev.fwnode,
2033 				     lp->phy_mode,
2034 				     &axienet_phylink_ops);
2035 	if (IS_ERR(lp->phylink)) {
2036 		ret = PTR_ERR(lp->phylink);
2037 		dev_err(&pdev->dev, "phylink_create error (%i)\n", ret);
2038 		goto free_netdev;
2039 	}
2040 
2041 	ret = register_netdev(lp->ndev);
2042 	if (ret) {
2043 		dev_err(lp->dev, "register_netdev() error (%i)\n", ret);
2044 		goto free_netdev;
2045 	}
2046 
2047 	return 0;
2048 
2049 free_netdev:
2050 	free_netdev(ndev);
2051 
2052 	return ret;
2053 }
2054 
2055 static int axienet_remove(struct platform_device *pdev)
2056 {
2057 	struct net_device *ndev = platform_get_drvdata(pdev);
2058 	struct axienet_local *lp = netdev_priv(ndev);
2059 
2060 	unregister_netdev(ndev);
2061 
2062 	if (lp->phylink)
2063 		phylink_destroy(lp->phylink);
2064 
2065 	if (lp->pcs_phy)
2066 		put_device(&lp->pcs_phy->dev);
2067 
2068 	axienet_mdio_teardown(lp);
2069 
2070 	clk_disable_unprepare(lp->clk);
2071 
2072 	of_node_put(lp->phy_node);
2073 	lp->phy_node = NULL;
2074 
2075 	free_netdev(ndev);
2076 
2077 	return 0;
2078 }
2079 
2080 static void axienet_shutdown(struct platform_device *pdev)
2081 {
2082 	struct net_device *ndev = platform_get_drvdata(pdev);
2083 
2084 	rtnl_lock();
2085 	netif_device_detach(ndev);
2086 
2087 	if (netif_running(ndev))
2088 		dev_close(ndev);
2089 
2090 	rtnl_unlock();
2091 }
2092 
2093 static struct platform_driver axienet_driver = {
2094 	.probe = axienet_probe,
2095 	.remove = axienet_remove,
2096 	.shutdown = axienet_shutdown,
2097 	.driver = {
2098 		 .name = "xilinx_axienet",
2099 		 .of_match_table = axienet_of_match,
2100 	},
2101 };
2102 
2103 module_platform_driver(axienet_driver);
2104 
2105 MODULE_DESCRIPTION("Xilinx Axi Ethernet driver");
2106 MODULE_AUTHOR("Xilinx");
2107 MODULE_LICENSE("GPL");
2108