xref: /openbmc/linux/drivers/net/ethernet/dnet.c (revision 54cbac81)
1 /*
2  * Dave DNET Ethernet Controller driver
3  *
4  * Copyright (C) 2008 Dave S.r.l. <www.dave.eu>
5  * Copyright (C) 2009 Ilya Yanok, Emcraft Systems Ltd, <yanok@emcraft.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/moduleparam.h>
14 #include <linux/kernel.h>
15 #include <linux/types.h>
16 #include <linux/slab.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/netdevice.h>
21 #include <linux/etherdevice.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/platform_device.h>
24 #include <linux/phy.h>
25 
26 #include "dnet.h"
27 
28 #undef DEBUG
29 
30 /* function for reading internal MAC register */
31 static u16 dnet_readw_mac(struct dnet *bp, u16 reg)
32 {
33 	u16 data_read;
34 
35 	/* issue a read */
36 	dnet_writel(bp, reg, MACREG_ADDR);
37 
38 	/* since a read/write op to the MAC is very slow,
39 	 * we must wait before reading the data */
40 	ndelay(500);
41 
42 	/* read data read from the MAC register */
43 	data_read = dnet_readl(bp, MACREG_DATA);
44 
45 	/* all done */
46 	return data_read;
47 }
48 
49 /* function for writing internal MAC register */
50 static void dnet_writew_mac(struct dnet *bp, u16 reg, u16 val)
51 {
52 	/* load data to write */
53 	dnet_writel(bp, val, MACREG_DATA);
54 
55 	/* issue a write */
56 	dnet_writel(bp, reg | DNET_INTERNAL_WRITE, MACREG_ADDR);
57 
58 	/* since a read/write op to the MAC is very slow,
59 	 * we must wait before exiting */
60 	ndelay(500);
61 }
62 
63 static void __dnet_set_hwaddr(struct dnet *bp)
64 {
65 	u16 tmp;
66 
67 	tmp = be16_to_cpup((__be16 *)bp->dev->dev_addr);
68 	dnet_writew_mac(bp, DNET_INTERNAL_MAC_ADDR_0_REG, tmp);
69 	tmp = be16_to_cpup((__be16 *)(bp->dev->dev_addr + 2));
70 	dnet_writew_mac(bp, DNET_INTERNAL_MAC_ADDR_1_REG, tmp);
71 	tmp = be16_to_cpup((__be16 *)(bp->dev->dev_addr + 4));
72 	dnet_writew_mac(bp, DNET_INTERNAL_MAC_ADDR_2_REG, tmp);
73 }
74 
75 static void dnet_get_hwaddr(struct dnet *bp)
76 {
77 	u16 tmp;
78 	u8 addr[6];
79 
80 	/*
81 	 * from MAC docs:
82 	 * "Note that the MAC address is stored in the registers in Hexadecimal
83 	 * form. For example, to set the MAC Address to: AC-DE-48-00-00-80
84 	 * would require writing 0xAC (octet 0) to address 0x0B (high byte of
85 	 * Mac_addr[15:0]), 0xDE (octet 1) to address 0x0A (Low byte of
86 	 * Mac_addr[15:0]), 0x48 (octet 2) to address 0x0D (high byte of
87 	 * Mac_addr[15:0]), 0x00 (octet 3) to address 0x0C (Low byte of
88 	 * Mac_addr[15:0]), 0x00 (octet 4) to address 0x0F (high byte of
89 	 * Mac_addr[15:0]), and 0x80 (octet 5) to address * 0x0E (Low byte of
90 	 * Mac_addr[15:0]).
91 	 */
92 	tmp = dnet_readw_mac(bp, DNET_INTERNAL_MAC_ADDR_0_REG);
93 	*((__be16 *)addr) = cpu_to_be16(tmp);
94 	tmp = dnet_readw_mac(bp, DNET_INTERNAL_MAC_ADDR_1_REG);
95 	*((__be16 *)(addr + 2)) = cpu_to_be16(tmp);
96 	tmp = dnet_readw_mac(bp, DNET_INTERNAL_MAC_ADDR_2_REG);
97 	*((__be16 *)(addr + 4)) = cpu_to_be16(tmp);
98 
99 	if (is_valid_ether_addr(addr))
100 		memcpy(bp->dev->dev_addr, addr, sizeof(addr));
101 }
102 
103 static int dnet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
104 {
105 	struct dnet *bp = bus->priv;
106 	u16 value;
107 
108 	while (!(dnet_readw_mac(bp, DNET_INTERNAL_GMII_MNG_CTL_REG)
109 				& DNET_INTERNAL_GMII_MNG_CMD_FIN))
110 		cpu_relax();
111 
112 	/* only 5 bits allowed for phy-addr and reg_offset */
113 	mii_id &= 0x1f;
114 	regnum &= 0x1f;
115 
116 	/* prepare reg_value for a read */
117 	value = (mii_id << 8);
118 	value |= regnum;
119 
120 	/* write control word */
121 	dnet_writew_mac(bp, DNET_INTERNAL_GMII_MNG_CTL_REG, value);
122 
123 	/* wait for end of transfer */
124 	while (!(dnet_readw_mac(bp, DNET_INTERNAL_GMII_MNG_CTL_REG)
125 				& DNET_INTERNAL_GMII_MNG_CMD_FIN))
126 		cpu_relax();
127 
128 	value = dnet_readw_mac(bp, DNET_INTERNAL_GMII_MNG_DAT_REG);
129 
130 	pr_debug("mdio_read %02x:%02x <- %04x\n", mii_id, regnum, value);
131 
132 	return value;
133 }
134 
135 static int dnet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
136 			   u16 value)
137 {
138 	struct dnet *bp = bus->priv;
139 	u16 tmp;
140 
141 	pr_debug("mdio_write %02x:%02x <- %04x\n", mii_id, regnum, value);
142 
143 	while (!(dnet_readw_mac(bp, DNET_INTERNAL_GMII_MNG_CTL_REG)
144 				& DNET_INTERNAL_GMII_MNG_CMD_FIN))
145 		cpu_relax();
146 
147 	/* prepare for a write operation */
148 	tmp = (1 << 13);
149 
150 	/* only 5 bits allowed for phy-addr and reg_offset */
151 	mii_id &= 0x1f;
152 	regnum &= 0x1f;
153 
154 	/* only 16 bits on data */
155 	value &= 0xffff;
156 
157 	/* prepare reg_value for a write */
158 	tmp |= (mii_id << 8);
159 	tmp |= regnum;
160 
161 	/* write data to write first */
162 	dnet_writew_mac(bp, DNET_INTERNAL_GMII_MNG_DAT_REG, value);
163 
164 	/* write control word */
165 	dnet_writew_mac(bp, DNET_INTERNAL_GMII_MNG_CTL_REG, tmp);
166 
167 	while (!(dnet_readw_mac(bp, DNET_INTERNAL_GMII_MNG_CTL_REG)
168 				& DNET_INTERNAL_GMII_MNG_CMD_FIN))
169 		cpu_relax();
170 
171 	return 0;
172 }
173 
174 static int dnet_mdio_reset(struct mii_bus *bus)
175 {
176 	return 0;
177 }
178 
179 static void dnet_handle_link_change(struct net_device *dev)
180 {
181 	struct dnet *bp = netdev_priv(dev);
182 	struct phy_device *phydev = bp->phy_dev;
183 	unsigned long flags;
184 	u32 mode_reg, ctl_reg;
185 
186 	int status_change = 0;
187 
188 	spin_lock_irqsave(&bp->lock, flags);
189 
190 	mode_reg = dnet_readw_mac(bp, DNET_INTERNAL_MODE_REG);
191 	ctl_reg = dnet_readw_mac(bp, DNET_INTERNAL_RXTX_CONTROL_REG);
192 
193 	if (phydev->link) {
194 		if (bp->duplex != phydev->duplex) {
195 			if (phydev->duplex)
196 				ctl_reg &=
197 				    ~(DNET_INTERNAL_RXTX_CONTROL_ENABLEHALFDUP);
198 			else
199 				ctl_reg |=
200 				    DNET_INTERNAL_RXTX_CONTROL_ENABLEHALFDUP;
201 
202 			bp->duplex = phydev->duplex;
203 			status_change = 1;
204 		}
205 
206 		if (bp->speed != phydev->speed) {
207 			status_change = 1;
208 			switch (phydev->speed) {
209 			case 1000:
210 				mode_reg |= DNET_INTERNAL_MODE_GBITEN;
211 				break;
212 			case 100:
213 			case 10:
214 				mode_reg &= ~DNET_INTERNAL_MODE_GBITEN;
215 				break;
216 			default:
217 				printk(KERN_WARNING
218 				       "%s: Ack!  Speed (%d) is not "
219 				       "10/100/1000!\n", dev->name,
220 				       phydev->speed);
221 				break;
222 			}
223 			bp->speed = phydev->speed;
224 		}
225 	}
226 
227 	if (phydev->link != bp->link) {
228 		if (phydev->link) {
229 			mode_reg |=
230 			    (DNET_INTERNAL_MODE_RXEN | DNET_INTERNAL_MODE_TXEN);
231 		} else {
232 			mode_reg &=
233 			    ~(DNET_INTERNAL_MODE_RXEN |
234 			      DNET_INTERNAL_MODE_TXEN);
235 			bp->speed = 0;
236 			bp->duplex = -1;
237 		}
238 		bp->link = phydev->link;
239 
240 		status_change = 1;
241 	}
242 
243 	if (status_change) {
244 		dnet_writew_mac(bp, DNET_INTERNAL_RXTX_CONTROL_REG, ctl_reg);
245 		dnet_writew_mac(bp, DNET_INTERNAL_MODE_REG, mode_reg);
246 	}
247 
248 	spin_unlock_irqrestore(&bp->lock, flags);
249 
250 	if (status_change) {
251 		if (phydev->link)
252 			printk(KERN_INFO "%s: link up (%d/%s)\n",
253 			       dev->name, phydev->speed,
254 			       DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
255 		else
256 			printk(KERN_INFO "%s: link down\n", dev->name);
257 	}
258 }
259 
260 static int dnet_mii_probe(struct net_device *dev)
261 {
262 	struct dnet *bp = netdev_priv(dev);
263 	struct phy_device *phydev = NULL;
264 	int phy_addr;
265 
266 	/* find the first phy */
267 	for (phy_addr = 0; phy_addr < PHY_MAX_ADDR; phy_addr++) {
268 		if (bp->mii_bus->phy_map[phy_addr]) {
269 			phydev = bp->mii_bus->phy_map[phy_addr];
270 			break;
271 		}
272 	}
273 
274 	if (!phydev) {
275 		printk(KERN_ERR "%s: no PHY found\n", dev->name);
276 		return -ENODEV;
277 	}
278 
279 	/* TODO : add pin_irq */
280 
281 	/* attach the mac to the phy */
282 	if (bp->capabilities & DNET_HAS_RMII) {
283 		phydev = phy_connect(dev, dev_name(&phydev->dev),
284 				     &dnet_handle_link_change, 0,
285 				     PHY_INTERFACE_MODE_RMII);
286 	} else {
287 		phydev = phy_connect(dev, dev_name(&phydev->dev),
288 				     &dnet_handle_link_change, 0,
289 				     PHY_INTERFACE_MODE_MII);
290 	}
291 
292 	if (IS_ERR(phydev)) {
293 		printk(KERN_ERR "%s: Could not attach to PHY\n", dev->name);
294 		return PTR_ERR(phydev);
295 	}
296 
297 	/* mask with MAC supported features */
298 	if (bp->capabilities & DNET_HAS_GIGABIT)
299 		phydev->supported &= PHY_GBIT_FEATURES;
300 	else
301 		phydev->supported &= PHY_BASIC_FEATURES;
302 
303 	phydev->supported |= SUPPORTED_Asym_Pause | SUPPORTED_Pause;
304 
305 	phydev->advertising = phydev->supported;
306 
307 	bp->link = 0;
308 	bp->speed = 0;
309 	bp->duplex = -1;
310 	bp->phy_dev = phydev;
311 
312 	return 0;
313 }
314 
315 static int dnet_mii_init(struct dnet *bp)
316 {
317 	int err, i;
318 
319 	bp->mii_bus = mdiobus_alloc();
320 	if (bp->mii_bus == NULL)
321 		return -ENOMEM;
322 
323 	bp->mii_bus->name = "dnet_mii_bus";
324 	bp->mii_bus->read = &dnet_mdio_read;
325 	bp->mii_bus->write = &dnet_mdio_write;
326 	bp->mii_bus->reset = &dnet_mdio_reset;
327 
328 	snprintf(bp->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
329 		bp->pdev->name, bp->pdev->id);
330 
331 	bp->mii_bus->priv = bp;
332 
333 	bp->mii_bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
334 	if (!bp->mii_bus->irq) {
335 		err = -ENOMEM;
336 		goto err_out;
337 	}
338 
339 	for (i = 0; i < PHY_MAX_ADDR; i++)
340 		bp->mii_bus->irq[i] = PHY_POLL;
341 
342 	if (mdiobus_register(bp->mii_bus)) {
343 		err = -ENXIO;
344 		goto err_out_free_mdio_irq;
345 	}
346 
347 	if (dnet_mii_probe(bp->dev) != 0) {
348 		err = -ENXIO;
349 		goto err_out_unregister_bus;
350 	}
351 
352 	return 0;
353 
354 err_out_unregister_bus:
355 	mdiobus_unregister(bp->mii_bus);
356 err_out_free_mdio_irq:
357 	kfree(bp->mii_bus->irq);
358 err_out:
359 	mdiobus_free(bp->mii_bus);
360 	return err;
361 }
362 
363 /* For Neptune board: LINK1000 as Link LED and TX as activity LED */
364 static int dnet_phy_marvell_fixup(struct phy_device *phydev)
365 {
366 	return phy_write(phydev, 0x18, 0x4148);
367 }
368 
369 static void dnet_update_stats(struct dnet *bp)
370 {
371 	u32 __iomem *reg = bp->regs + DNET_RX_PKT_IGNR_CNT;
372 	u32 *p = &bp->hw_stats.rx_pkt_ignr;
373 	u32 *end = &bp->hw_stats.rx_byte + 1;
374 
375 	WARN_ON((unsigned long)(end - p - 1) !=
376 		(DNET_RX_BYTE_CNT - DNET_RX_PKT_IGNR_CNT) / 4);
377 
378 	for (; p < end; p++, reg++)
379 		*p += readl(reg);
380 
381 	reg = bp->regs + DNET_TX_UNICAST_CNT;
382 	p = &bp->hw_stats.tx_unicast;
383 	end = &bp->hw_stats.tx_byte + 1;
384 
385 	WARN_ON((unsigned long)(end - p - 1) !=
386 		(DNET_TX_BYTE_CNT - DNET_TX_UNICAST_CNT) / 4);
387 
388 	for (; p < end; p++, reg++)
389 		*p += readl(reg);
390 }
391 
392 static int dnet_poll(struct napi_struct *napi, int budget)
393 {
394 	struct dnet *bp = container_of(napi, struct dnet, napi);
395 	struct net_device *dev = bp->dev;
396 	int npackets = 0;
397 	unsigned int pkt_len;
398 	struct sk_buff *skb;
399 	unsigned int *data_ptr;
400 	u32 int_enable;
401 	u32 cmd_word;
402 	int i;
403 
404 	while (npackets < budget) {
405 		/*
406 		 * break out of while loop if there are no more
407 		 * packets waiting
408 		 */
409 		if (!(dnet_readl(bp, RX_FIFO_WCNT) >> 16)) {
410 			napi_complete(napi);
411 			int_enable = dnet_readl(bp, INTR_ENB);
412 			int_enable |= DNET_INTR_SRC_RX_CMDFIFOAF;
413 			dnet_writel(bp, int_enable, INTR_ENB);
414 			return 0;
415 		}
416 
417 		cmd_word = dnet_readl(bp, RX_LEN_FIFO);
418 		pkt_len = cmd_word & 0xFFFF;
419 
420 		if (cmd_word & 0xDF180000)
421 			printk(KERN_ERR "%s packet receive error %x\n",
422 			       __func__, cmd_word);
423 
424 		skb = netdev_alloc_skb(dev, pkt_len + 5);
425 		if (skb != NULL) {
426 			/* Align IP on 16 byte boundaries */
427 			skb_reserve(skb, 2);
428 			/*
429 			 * 'skb_put()' points to the start of sk_buff
430 			 * data area.
431 			 */
432 			data_ptr = (unsigned int *)skb_put(skb, pkt_len);
433 			for (i = 0; i < (pkt_len + 3) >> 2; i++)
434 				*data_ptr++ = dnet_readl(bp, RX_DATA_FIFO);
435 			skb->protocol = eth_type_trans(skb, dev);
436 			netif_receive_skb(skb);
437 			npackets++;
438 		} else
439 			printk(KERN_NOTICE
440 			       "%s: No memory to allocate a sk_buff of "
441 			       "size %u.\n", dev->name, pkt_len);
442 	}
443 
444 	budget -= npackets;
445 
446 	if (npackets < budget) {
447 		/* We processed all packets available.  Tell NAPI it can
448 		 * stop polling then re-enable rx interrupts */
449 		napi_complete(napi);
450 		int_enable = dnet_readl(bp, INTR_ENB);
451 		int_enable |= DNET_INTR_SRC_RX_CMDFIFOAF;
452 		dnet_writel(bp, int_enable, INTR_ENB);
453 		return 0;
454 	}
455 
456 	/* There are still packets waiting */
457 	return 1;
458 }
459 
460 static irqreturn_t dnet_interrupt(int irq, void *dev_id)
461 {
462 	struct net_device *dev = dev_id;
463 	struct dnet *bp = netdev_priv(dev);
464 	u32 int_src, int_enable, int_current;
465 	unsigned long flags;
466 	unsigned int handled = 0;
467 
468 	spin_lock_irqsave(&bp->lock, flags);
469 
470 	/* read and clear the DNET irq (clear on read) */
471 	int_src = dnet_readl(bp, INTR_SRC);
472 	int_enable = dnet_readl(bp, INTR_ENB);
473 	int_current = int_src & int_enable;
474 
475 	/* restart the queue if we had stopped it for TX fifo almost full */
476 	if (int_current & DNET_INTR_SRC_TX_FIFOAE) {
477 		int_enable = dnet_readl(bp, INTR_ENB);
478 		int_enable &= ~DNET_INTR_ENB_TX_FIFOAE;
479 		dnet_writel(bp, int_enable, INTR_ENB);
480 		netif_wake_queue(dev);
481 		handled = 1;
482 	}
483 
484 	/* RX FIFO error checking */
485 	if (int_current &
486 	    (DNET_INTR_SRC_RX_CMDFIFOFF | DNET_INTR_SRC_RX_DATAFIFOFF)) {
487 		printk(KERN_ERR "%s: RX fifo error %x, irq %x\n", __func__,
488 		       dnet_readl(bp, RX_STATUS), int_current);
489 		/* we can only flush the RX FIFOs */
490 		dnet_writel(bp, DNET_SYS_CTL_RXFIFOFLUSH, SYS_CTL);
491 		ndelay(500);
492 		dnet_writel(bp, 0, SYS_CTL);
493 		handled = 1;
494 	}
495 
496 	/* TX FIFO error checking */
497 	if (int_current &
498 	    (DNET_INTR_SRC_TX_FIFOFULL | DNET_INTR_SRC_TX_DISCFRM)) {
499 		printk(KERN_ERR "%s: TX fifo error %x, irq %x\n", __func__,
500 		       dnet_readl(bp, TX_STATUS), int_current);
501 		/* we can only flush the TX FIFOs */
502 		dnet_writel(bp, DNET_SYS_CTL_TXFIFOFLUSH, SYS_CTL);
503 		ndelay(500);
504 		dnet_writel(bp, 0, SYS_CTL);
505 		handled = 1;
506 	}
507 
508 	if (int_current & DNET_INTR_SRC_RX_CMDFIFOAF) {
509 		if (napi_schedule_prep(&bp->napi)) {
510 			/*
511 			 * There's no point taking any more interrupts
512 			 * until we have processed the buffers
513 			 */
514 			/* Disable Rx interrupts and schedule NAPI poll */
515 			int_enable = dnet_readl(bp, INTR_ENB);
516 			int_enable &= ~DNET_INTR_SRC_RX_CMDFIFOAF;
517 			dnet_writel(bp, int_enable, INTR_ENB);
518 			__napi_schedule(&bp->napi);
519 		}
520 		handled = 1;
521 	}
522 
523 	if (!handled)
524 		pr_debug("%s: irq %x remains\n", __func__, int_current);
525 
526 	spin_unlock_irqrestore(&bp->lock, flags);
527 
528 	return IRQ_RETVAL(handled);
529 }
530 
531 #ifdef DEBUG
532 static inline void dnet_print_skb(struct sk_buff *skb)
533 {
534 	int k;
535 	printk(KERN_DEBUG PFX "data:");
536 	for (k = 0; k < skb->len; k++)
537 		printk(" %02x", (unsigned int)skb->data[k]);
538 	printk("\n");
539 }
540 #else
541 #define dnet_print_skb(skb)	do {} while (0)
542 #endif
543 
544 static netdev_tx_t dnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
545 {
546 
547 	struct dnet *bp = netdev_priv(dev);
548 	u32 tx_status, irq_enable;
549 	unsigned int len, i, tx_cmd, wrsz;
550 	unsigned long flags;
551 	unsigned int *bufp;
552 
553 	tx_status = dnet_readl(bp, TX_STATUS);
554 
555 	pr_debug("start_xmit: len %u head %p data %p\n",
556 	       skb->len, skb->head, skb->data);
557 	dnet_print_skb(skb);
558 
559 	/* frame size (words) */
560 	len = (skb->len + 3) >> 2;
561 
562 	spin_lock_irqsave(&bp->lock, flags);
563 
564 	tx_status = dnet_readl(bp, TX_STATUS);
565 
566 	bufp = (unsigned int *)(((unsigned long) skb->data) & ~0x3UL);
567 	wrsz = (u32) skb->len + 3;
568 	wrsz += ((unsigned long) skb->data) & 0x3;
569 	wrsz >>= 2;
570 	tx_cmd = ((((unsigned long)(skb->data)) & 0x03) << 16) | (u32) skb->len;
571 
572 	/* check if there is enough room for the current frame */
573 	if (wrsz < (DNET_FIFO_SIZE - dnet_readl(bp, TX_FIFO_WCNT))) {
574 		for (i = 0; i < wrsz; i++)
575 			dnet_writel(bp, *bufp++, TX_DATA_FIFO);
576 
577 		/*
578 		 * inform MAC that a packet's written and ready to be
579 		 * shipped out
580 		 */
581 		dnet_writel(bp, tx_cmd, TX_LEN_FIFO);
582 	}
583 
584 	if (dnet_readl(bp, TX_FIFO_WCNT) > DNET_FIFO_TX_DATA_AF_TH) {
585 		netif_stop_queue(dev);
586 		tx_status = dnet_readl(bp, INTR_SRC);
587 		irq_enable = dnet_readl(bp, INTR_ENB);
588 		irq_enable |= DNET_INTR_ENB_TX_FIFOAE;
589 		dnet_writel(bp, irq_enable, INTR_ENB);
590 	}
591 
592 	skb_tx_timestamp(skb);
593 
594 	/* free the buffer */
595 	dev_kfree_skb(skb);
596 
597 	spin_unlock_irqrestore(&bp->lock, flags);
598 
599 	return NETDEV_TX_OK;
600 }
601 
602 static void dnet_reset_hw(struct dnet *bp)
603 {
604 	/* put ts_mac in IDLE state i.e. disable rx/tx */
605 	dnet_writew_mac(bp, DNET_INTERNAL_MODE_REG, DNET_INTERNAL_MODE_FCEN);
606 
607 	/*
608 	 * RX FIFO almost full threshold: only cmd FIFO almost full is
609 	 * implemented for RX side
610 	 */
611 	dnet_writel(bp, DNET_FIFO_RX_CMD_AF_TH, RX_FIFO_TH);
612 	/*
613 	 * TX FIFO almost empty threshold: only data FIFO almost empty
614 	 * is implemented for TX side
615 	 */
616 	dnet_writel(bp, DNET_FIFO_TX_DATA_AE_TH, TX_FIFO_TH);
617 
618 	/* flush rx/tx fifos */
619 	dnet_writel(bp, DNET_SYS_CTL_RXFIFOFLUSH | DNET_SYS_CTL_TXFIFOFLUSH,
620 			SYS_CTL);
621 	msleep(1);
622 	dnet_writel(bp, 0, SYS_CTL);
623 }
624 
625 static void dnet_init_hw(struct dnet *bp)
626 {
627 	u32 config;
628 
629 	dnet_reset_hw(bp);
630 	__dnet_set_hwaddr(bp);
631 
632 	config = dnet_readw_mac(bp, DNET_INTERNAL_RXTX_CONTROL_REG);
633 
634 	if (bp->dev->flags & IFF_PROMISC)
635 		/* Copy All Frames */
636 		config |= DNET_INTERNAL_RXTX_CONTROL_ENPROMISC;
637 	if (!(bp->dev->flags & IFF_BROADCAST))
638 		/* No BroadCast */
639 		config |= DNET_INTERNAL_RXTX_CONTROL_RXMULTICAST;
640 
641 	config |= DNET_INTERNAL_RXTX_CONTROL_RXPAUSE |
642 	    DNET_INTERNAL_RXTX_CONTROL_RXBROADCAST |
643 	    DNET_INTERNAL_RXTX_CONTROL_DROPCONTROL |
644 	    DNET_INTERNAL_RXTX_CONTROL_DISCFXFCS;
645 
646 	dnet_writew_mac(bp, DNET_INTERNAL_RXTX_CONTROL_REG, config);
647 
648 	/* clear irq before enabling them */
649 	config = dnet_readl(bp, INTR_SRC);
650 
651 	/* enable RX/TX interrupt, recv packet ready interrupt */
652 	dnet_writel(bp, DNET_INTR_ENB_GLOBAL_ENABLE | DNET_INTR_ENB_RX_SUMMARY |
653 			DNET_INTR_ENB_TX_SUMMARY | DNET_INTR_ENB_RX_FIFOERR |
654 			DNET_INTR_ENB_RX_ERROR | DNET_INTR_ENB_RX_FIFOFULL |
655 			DNET_INTR_ENB_TX_FIFOFULL | DNET_INTR_ENB_TX_DISCFRM |
656 			DNET_INTR_ENB_RX_PKTRDY, INTR_ENB);
657 }
658 
659 static int dnet_open(struct net_device *dev)
660 {
661 	struct dnet *bp = netdev_priv(dev);
662 
663 	/* if the phy is not yet register, retry later */
664 	if (!bp->phy_dev)
665 		return -EAGAIN;
666 
667 	napi_enable(&bp->napi);
668 	dnet_init_hw(bp);
669 
670 	phy_start_aneg(bp->phy_dev);
671 
672 	/* schedule a link state check */
673 	phy_start(bp->phy_dev);
674 
675 	netif_start_queue(dev);
676 
677 	return 0;
678 }
679 
680 static int dnet_close(struct net_device *dev)
681 {
682 	struct dnet *bp = netdev_priv(dev);
683 
684 	netif_stop_queue(dev);
685 	napi_disable(&bp->napi);
686 
687 	if (bp->phy_dev)
688 		phy_stop(bp->phy_dev);
689 
690 	dnet_reset_hw(bp);
691 	netif_carrier_off(dev);
692 
693 	return 0;
694 }
695 
696 static inline void dnet_print_pretty_hwstats(struct dnet_stats *hwstat)
697 {
698 	pr_debug("%s\n", __func__);
699 	pr_debug("----------------------------- RX statistics "
700 		 "-------------------------------\n");
701 	pr_debug("RX_PKT_IGNR_CNT %-8x\n", hwstat->rx_pkt_ignr);
702 	pr_debug("RX_LEN_CHK_ERR_CNT %-8x\n", hwstat->rx_len_chk_err);
703 	pr_debug("RX_LNG_FRM_CNT %-8x\n", hwstat->rx_lng_frm);
704 	pr_debug("RX_SHRT_FRM_CNT %-8x\n", hwstat->rx_shrt_frm);
705 	pr_debug("RX_IPG_VIOL_CNT %-8x\n", hwstat->rx_ipg_viol);
706 	pr_debug("RX_CRC_ERR_CNT %-8x\n", hwstat->rx_crc_err);
707 	pr_debug("RX_OK_PKT_CNT %-8x\n", hwstat->rx_ok_pkt);
708 	pr_debug("RX_CTL_FRM_CNT %-8x\n", hwstat->rx_ctl_frm);
709 	pr_debug("RX_PAUSE_FRM_CNT %-8x\n", hwstat->rx_pause_frm);
710 	pr_debug("RX_MULTICAST_CNT %-8x\n", hwstat->rx_multicast);
711 	pr_debug("RX_BROADCAST_CNT %-8x\n", hwstat->rx_broadcast);
712 	pr_debug("RX_VLAN_TAG_CNT %-8x\n", hwstat->rx_vlan_tag);
713 	pr_debug("RX_PRE_SHRINK_CNT %-8x\n", hwstat->rx_pre_shrink);
714 	pr_debug("RX_DRIB_NIB_CNT %-8x\n", hwstat->rx_drib_nib);
715 	pr_debug("RX_UNSUP_OPCD_CNT %-8x\n", hwstat->rx_unsup_opcd);
716 	pr_debug("RX_BYTE_CNT %-8x\n", hwstat->rx_byte);
717 	pr_debug("----------------------------- TX statistics "
718 		 "-------------------------------\n");
719 	pr_debug("TX_UNICAST_CNT %-8x\n", hwstat->tx_unicast);
720 	pr_debug("TX_PAUSE_FRM_CNT %-8x\n", hwstat->tx_pause_frm);
721 	pr_debug("TX_MULTICAST_CNT %-8x\n", hwstat->tx_multicast);
722 	pr_debug("TX_BRDCAST_CNT %-8x\n", hwstat->tx_brdcast);
723 	pr_debug("TX_VLAN_TAG_CNT %-8x\n", hwstat->tx_vlan_tag);
724 	pr_debug("TX_BAD_FCS_CNT %-8x\n", hwstat->tx_bad_fcs);
725 	pr_debug("TX_JUMBO_CNT %-8x\n", hwstat->tx_jumbo);
726 	pr_debug("TX_BYTE_CNT %-8x\n", hwstat->tx_byte);
727 }
728 
729 static struct net_device_stats *dnet_get_stats(struct net_device *dev)
730 {
731 
732 	struct dnet *bp = netdev_priv(dev);
733 	struct net_device_stats *nstat = &dev->stats;
734 	struct dnet_stats *hwstat = &bp->hw_stats;
735 
736 	/* read stats from hardware */
737 	dnet_update_stats(bp);
738 
739 	/* Convert HW stats into netdevice stats */
740 	nstat->rx_errors = (hwstat->rx_len_chk_err +
741 			    hwstat->rx_lng_frm + hwstat->rx_shrt_frm +
742 			    /* ignore IGP violation error
743 			    hwstat->rx_ipg_viol + */
744 			    hwstat->rx_crc_err +
745 			    hwstat->rx_pre_shrink +
746 			    hwstat->rx_drib_nib + hwstat->rx_unsup_opcd);
747 	nstat->tx_errors = hwstat->tx_bad_fcs;
748 	nstat->rx_length_errors = (hwstat->rx_len_chk_err +
749 				   hwstat->rx_lng_frm +
750 				   hwstat->rx_shrt_frm + hwstat->rx_pre_shrink);
751 	nstat->rx_crc_errors = hwstat->rx_crc_err;
752 	nstat->rx_frame_errors = hwstat->rx_pre_shrink + hwstat->rx_drib_nib;
753 	nstat->rx_packets = hwstat->rx_ok_pkt;
754 	nstat->tx_packets = (hwstat->tx_unicast +
755 			     hwstat->tx_multicast + hwstat->tx_brdcast);
756 	nstat->rx_bytes = hwstat->rx_byte;
757 	nstat->tx_bytes = hwstat->tx_byte;
758 	nstat->multicast = hwstat->rx_multicast;
759 	nstat->rx_missed_errors = hwstat->rx_pkt_ignr;
760 
761 	dnet_print_pretty_hwstats(hwstat);
762 
763 	return nstat;
764 }
765 
766 static int dnet_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
767 {
768 	struct dnet *bp = netdev_priv(dev);
769 	struct phy_device *phydev = bp->phy_dev;
770 
771 	if (!phydev)
772 		return -ENODEV;
773 
774 	return phy_ethtool_gset(phydev, cmd);
775 }
776 
777 static int dnet_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
778 {
779 	struct dnet *bp = netdev_priv(dev);
780 	struct phy_device *phydev = bp->phy_dev;
781 
782 	if (!phydev)
783 		return -ENODEV;
784 
785 	return phy_ethtool_sset(phydev, cmd);
786 }
787 
788 static int dnet_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
789 {
790 	struct dnet *bp = netdev_priv(dev);
791 	struct phy_device *phydev = bp->phy_dev;
792 
793 	if (!netif_running(dev))
794 		return -EINVAL;
795 
796 	if (!phydev)
797 		return -ENODEV;
798 
799 	return phy_mii_ioctl(phydev, rq, cmd);
800 }
801 
802 static void dnet_get_drvinfo(struct net_device *dev,
803 			     struct ethtool_drvinfo *info)
804 {
805 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
806 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
807 	strlcpy(info->bus_info, "0", sizeof(info->bus_info));
808 }
809 
810 static const struct ethtool_ops dnet_ethtool_ops = {
811 	.get_settings		= dnet_get_settings,
812 	.set_settings		= dnet_set_settings,
813 	.get_drvinfo		= dnet_get_drvinfo,
814 	.get_link		= ethtool_op_get_link,
815 	.get_ts_info		= ethtool_op_get_ts_info,
816 };
817 
818 static const struct net_device_ops dnet_netdev_ops = {
819 	.ndo_open		= dnet_open,
820 	.ndo_stop		= dnet_close,
821 	.ndo_get_stats		= dnet_get_stats,
822 	.ndo_start_xmit		= dnet_start_xmit,
823 	.ndo_do_ioctl		= dnet_ioctl,
824 	.ndo_set_mac_address	= eth_mac_addr,
825 	.ndo_validate_addr	= eth_validate_addr,
826 	.ndo_change_mtu		= eth_change_mtu,
827 };
828 
829 static int dnet_probe(struct platform_device *pdev)
830 {
831 	struct resource *res;
832 	struct net_device *dev;
833 	struct dnet *bp;
834 	struct phy_device *phydev;
835 	int err = -ENXIO;
836 	unsigned int mem_base, mem_size, irq;
837 
838 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
839 	if (!res) {
840 		dev_err(&pdev->dev, "no mmio resource defined\n");
841 		goto err_out;
842 	}
843 	mem_base = res->start;
844 	mem_size = resource_size(res);
845 	irq = platform_get_irq(pdev, 0);
846 
847 	if (!request_mem_region(mem_base, mem_size, DRV_NAME)) {
848 		dev_err(&pdev->dev, "no memory region available\n");
849 		err = -EBUSY;
850 		goto err_out;
851 	}
852 
853 	err = -ENOMEM;
854 	dev = alloc_etherdev(sizeof(*bp));
855 	if (!dev)
856 		goto err_out_release_mem;
857 
858 	/* TODO: Actually, we have some interesting features... */
859 	dev->features |= 0;
860 
861 	bp = netdev_priv(dev);
862 	bp->dev = dev;
863 
864 	platform_set_drvdata(pdev, dev);
865 	SET_NETDEV_DEV(dev, &pdev->dev);
866 
867 	spin_lock_init(&bp->lock);
868 
869 	bp->regs = ioremap(mem_base, mem_size);
870 	if (!bp->regs) {
871 		dev_err(&pdev->dev, "failed to map registers, aborting.\n");
872 		err = -ENOMEM;
873 		goto err_out_free_dev;
874 	}
875 
876 	dev->irq = irq;
877 	err = request_irq(dev->irq, dnet_interrupt, 0, DRV_NAME, dev);
878 	if (err) {
879 		dev_err(&pdev->dev, "Unable to request IRQ %d (error %d)\n",
880 		       irq, err);
881 		goto err_out_iounmap;
882 	}
883 
884 	dev->netdev_ops = &dnet_netdev_ops;
885 	netif_napi_add(dev, &bp->napi, dnet_poll, 64);
886 	dev->ethtool_ops = &dnet_ethtool_ops;
887 
888 	dev->base_addr = (unsigned long)bp->regs;
889 
890 	bp->capabilities = dnet_readl(bp, VERCAPS) & DNET_CAPS_MASK;
891 
892 	dnet_get_hwaddr(bp);
893 
894 	if (!is_valid_ether_addr(dev->dev_addr)) {
895 		/* choose a random ethernet address */
896 		eth_hw_addr_random(dev);
897 		__dnet_set_hwaddr(bp);
898 	}
899 
900 	err = register_netdev(dev);
901 	if (err) {
902 		dev_err(&pdev->dev, "Cannot register net device, aborting.\n");
903 		goto err_out_free_irq;
904 	}
905 
906 	/* register the PHY board fixup (for Marvell 88E1111) */
907 	err = phy_register_fixup_for_uid(0x01410cc0, 0xfffffff0,
908 					 dnet_phy_marvell_fixup);
909 	/* we can live without it, so just issue a warning */
910 	if (err)
911 		dev_warn(&pdev->dev, "Cannot register PHY board fixup.\n");
912 
913 	err = dnet_mii_init(bp);
914 	if (err)
915 		goto err_out_unregister_netdev;
916 
917 	dev_info(&pdev->dev, "Dave DNET at 0x%p (0x%08x) irq %d %pM\n",
918 	       bp->regs, mem_base, dev->irq, dev->dev_addr);
919 	dev_info(&pdev->dev, "has %smdio, %sirq, %sgigabit, %sdma\n",
920 	       (bp->capabilities & DNET_HAS_MDIO) ? "" : "no ",
921 	       (bp->capabilities & DNET_HAS_IRQ) ? "" : "no ",
922 	       (bp->capabilities & DNET_HAS_GIGABIT) ? "" : "no ",
923 	       (bp->capabilities & DNET_HAS_DMA) ? "" : "no ");
924 	phydev = bp->phy_dev;
925 	dev_info(&pdev->dev, "attached PHY driver [%s] "
926 	       "(mii_bus:phy_addr=%s, irq=%d)\n",
927 	       phydev->drv->name, dev_name(&phydev->dev), phydev->irq);
928 
929 	return 0;
930 
931 err_out_unregister_netdev:
932 	unregister_netdev(dev);
933 err_out_free_irq:
934 	free_irq(dev->irq, dev);
935 err_out_iounmap:
936 	iounmap(bp->regs);
937 err_out_free_dev:
938 	free_netdev(dev);
939 err_out_release_mem:
940 	release_mem_region(mem_base, mem_size);
941 err_out:
942 	return err;
943 }
944 
945 static int dnet_remove(struct platform_device *pdev)
946 {
947 
948 	struct net_device *dev;
949 	struct dnet *bp;
950 
951 	dev = platform_get_drvdata(pdev);
952 
953 	if (dev) {
954 		bp = netdev_priv(dev);
955 		if (bp->phy_dev)
956 			phy_disconnect(bp->phy_dev);
957 		mdiobus_unregister(bp->mii_bus);
958 		kfree(bp->mii_bus->irq);
959 		mdiobus_free(bp->mii_bus);
960 		unregister_netdev(dev);
961 		free_irq(dev->irq, dev);
962 		iounmap(bp->regs);
963 		free_netdev(dev);
964 	}
965 
966 	return 0;
967 }
968 
969 static struct platform_driver dnet_driver = {
970 	.probe		= dnet_probe,
971 	.remove		= dnet_remove,
972 	.driver		= {
973 		.name		= "dnet",
974 	},
975 };
976 
977 module_platform_driver(dnet_driver);
978 
979 MODULE_LICENSE("GPL");
980 MODULE_DESCRIPTION("Dave DNET Ethernet driver");
981 MODULE_AUTHOR("Ilya Yanok <yanok@emcraft.com>, "
982 	      "Matteo Vit <matteo.vit@dave.eu>");
983