xref: /linux/drivers/net/ethernet/micrel/ks8851_common.c (revision b8265621f4888af9494e1d685620871ec81bc33d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* drivers/net/ethernet/micrel/ks8851.c
3  *
4  * Copyright 2009 Simtec Electronics
5  *	http://www.simtec.co.uk/
6  *	Ben Dooks <ben@simtec.co.uk>
7  */
8 
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 
11 #define DEBUG
12 
13 #include <linux/interrupt.h>
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/ethtool.h>
19 #include <linux/cache.h>
20 #include <linux/crc32.h>
21 #include <linux/mii.h>
22 #include <linux/regulator/consumer.h>
23 
24 #include <linux/gpio.h>
25 #include <linux/of_gpio.h>
26 #include <linux/of_net.h>
27 
28 #include "ks8851.h"
29 
30 /**
31  * ks8851_lock - register access lock
32  * @ks: The chip state
33  * @flags: Spinlock flags
34  *
35  * Claim chip register access lock
36  */
37 static void ks8851_lock(struct ks8851_net *ks, unsigned long *flags)
38 {
39 	ks->lock(ks, flags);
40 }
41 
42 /**
43  * ks8851_unlock - register access unlock
44  * @ks: The chip state
45  * @flags: Spinlock flags
46  *
47  * Release chip register access lock
48  */
49 static void ks8851_unlock(struct ks8851_net *ks, unsigned long *flags)
50 {
51 	ks->unlock(ks, flags);
52 }
53 
54 /**
55  * ks8851_wrreg16 - write 16bit register value to chip
56  * @ks: The chip state
57  * @reg: The register address
58  * @val: The value to write
59  *
60  * Issue a write to put the value @val into the register specified in @reg.
61  */
62 static void ks8851_wrreg16(struct ks8851_net *ks, unsigned int reg,
63 			   unsigned int val)
64 {
65 	ks->wrreg16(ks, reg, val);
66 }
67 
68 /**
69  * ks8851_rdreg16 - read 16 bit register from device
70  * @ks: The chip information
71  * @reg: The register address
72  *
73  * Read a 16bit register from the chip, returning the result
74  */
75 static unsigned int ks8851_rdreg16(struct ks8851_net *ks,
76 				   unsigned int reg)
77 {
78 	return ks->rdreg16(ks, reg);
79 }
80 
81 /**
82  * ks8851_soft_reset - issue one of the soft reset to the device
83  * @ks: The device state.
84  * @op: The bit(s) to set in the GRR
85  *
86  * Issue the relevant soft-reset command to the device's GRR register
87  * specified by @op.
88  *
89  * Note, the delays are in there as a caution to ensure that the reset
90  * has time to take effect and then complete. Since the datasheet does
91  * not currently specify the exact sequence, we have chosen something
92  * that seems to work with our device.
93  */
94 static void ks8851_soft_reset(struct ks8851_net *ks, unsigned op)
95 {
96 	ks8851_wrreg16(ks, KS_GRR, op);
97 	mdelay(1);	/* wait a short time to effect reset */
98 	ks8851_wrreg16(ks, KS_GRR, 0);
99 	mdelay(1);	/* wait for condition to clear */
100 }
101 
102 /**
103  * ks8851_set_powermode - set power mode of the device
104  * @ks: The device state
105  * @pwrmode: The power mode value to write to KS_PMECR.
106  *
107  * Change the power mode of the chip.
108  */
109 static void ks8851_set_powermode(struct ks8851_net *ks, unsigned pwrmode)
110 {
111 	unsigned pmecr;
112 
113 	netif_dbg(ks, hw, ks->netdev, "setting power mode %d\n", pwrmode);
114 
115 	pmecr = ks8851_rdreg16(ks, KS_PMECR);
116 	pmecr &= ~PMECR_PM_MASK;
117 	pmecr |= pwrmode;
118 
119 	ks8851_wrreg16(ks, KS_PMECR, pmecr);
120 }
121 
122 /**
123  * ks8851_write_mac_addr - write mac address to device registers
124  * @dev: The network device
125  *
126  * Update the KS8851 MAC address registers from the address in @dev.
127  *
128  * This call assumes that the chip is not running, so there is no need to
129  * shutdown the RXQ process whilst setting this.
130 */
131 static int ks8851_write_mac_addr(struct net_device *dev)
132 {
133 	struct ks8851_net *ks = netdev_priv(dev);
134 	unsigned long flags;
135 	u16 val;
136 	int i;
137 
138 	ks8851_lock(ks, &flags);
139 
140 	/*
141 	 * Wake up chip in case it was powered off when stopped; otherwise,
142 	 * the first write to the MAC address does not take effect.
143 	 */
144 	ks8851_set_powermode(ks, PMECR_PM_NORMAL);
145 
146 	for (i = 0; i < ETH_ALEN; i += 2) {
147 		val = (dev->dev_addr[i] << 8) | dev->dev_addr[i + 1];
148 		ks8851_wrreg16(ks, KS_MAR(i), val);
149 	}
150 
151 	if (!netif_running(dev))
152 		ks8851_set_powermode(ks, PMECR_PM_SOFTDOWN);
153 
154 	ks8851_unlock(ks, &flags);
155 
156 	return 0;
157 }
158 
159 /**
160  * ks8851_read_mac_addr - read mac address from device registers
161  * @dev: The network device
162  *
163  * Update our copy of the KS8851 MAC address from the registers of @dev.
164 */
165 static void ks8851_read_mac_addr(struct net_device *dev)
166 {
167 	struct ks8851_net *ks = netdev_priv(dev);
168 	unsigned long flags;
169 	u16 reg;
170 	int i;
171 
172 	ks8851_lock(ks, &flags);
173 
174 	for (i = 0; i < ETH_ALEN; i += 2) {
175 		reg = ks8851_rdreg16(ks, KS_MAR(i));
176 		dev->dev_addr[i] = reg >> 8;
177 		dev->dev_addr[i + 1] = reg & 0xff;
178 	}
179 
180 	ks8851_unlock(ks, &flags);
181 }
182 
183 /**
184  * ks8851_init_mac - initialise the mac address
185  * @ks: The device structure
186  * @np: The device node pointer
187  *
188  * Get or create the initial mac address for the device and then set that
189  * into the station address register. A mac address supplied in the device
190  * tree takes precedence. Otherwise, if there is an EEPROM present, then
191  * we try that. If no valid mac address is found we use eth_random_addr()
192  * to create a new one.
193  */
194 static void ks8851_init_mac(struct ks8851_net *ks, struct device_node *np)
195 {
196 	struct net_device *dev = ks->netdev;
197 	const u8 *mac_addr;
198 
199 	mac_addr = of_get_mac_address(np);
200 	if (!IS_ERR(mac_addr)) {
201 		ether_addr_copy(dev->dev_addr, mac_addr);
202 		ks8851_write_mac_addr(dev);
203 		return;
204 	}
205 
206 	if (ks->rc_ccr & CCR_EEPROM) {
207 		ks8851_read_mac_addr(dev);
208 		if (is_valid_ether_addr(dev->dev_addr))
209 			return;
210 
211 		netdev_err(ks->netdev, "invalid mac address read %pM\n",
212 				dev->dev_addr);
213 	}
214 
215 	eth_hw_addr_random(dev);
216 	ks8851_write_mac_addr(dev);
217 }
218 
219 /**
220  * ks8851_dbg_dumpkkt - dump initial packet contents to debug
221  * @ks: The device state
222  * @rxpkt: The data for the received packet
223  *
224  * Dump the initial data from the packet to dev_dbg().
225  */
226 static void ks8851_dbg_dumpkkt(struct ks8851_net *ks, u8 *rxpkt)
227 {
228 	netdev_dbg(ks->netdev,
229 		   "pkt %02x%02x%02x%02x %02x%02x%02x%02x %02x%02x%02x%02x\n",
230 		   rxpkt[4], rxpkt[5], rxpkt[6], rxpkt[7],
231 		   rxpkt[8], rxpkt[9], rxpkt[10], rxpkt[11],
232 		   rxpkt[12], rxpkt[13], rxpkt[14], rxpkt[15]);
233 }
234 
235 /**
236  * ks8851_rx_skb - receive skbuff
237  * @ks: The device state.
238  * @skb: The skbuff
239  */
240 static void ks8851_rx_skb(struct ks8851_net *ks, struct sk_buff *skb)
241 {
242 	ks->rx_skb(ks, skb);
243 }
244 
245 /**
246  * ks8851_rx_pkts - receive packets from the host
247  * @ks: The device information.
248  *
249  * This is called from the IRQ work queue when the system detects that there
250  * are packets in the receive queue. Find out how many packets there are and
251  * read them from the FIFO.
252  */
253 static void ks8851_rx_pkts(struct ks8851_net *ks)
254 {
255 	struct sk_buff *skb;
256 	unsigned rxfc;
257 	unsigned rxlen;
258 	unsigned rxstat;
259 	u8 *rxpkt;
260 
261 	rxfc = (ks8851_rdreg16(ks, KS_RXFCTR) >> 8) & 0xff;
262 
263 	netif_dbg(ks, rx_status, ks->netdev,
264 		  "%s: %d packets\n", __func__, rxfc);
265 
266 	/* Currently we're issuing a read per packet, but we could possibly
267 	 * improve the code by issuing a single read, getting the receive
268 	 * header, allocating the packet and then reading the packet data
269 	 * out in one go.
270 	 *
271 	 * This form of operation would require us to hold the SPI bus'
272 	 * chipselect low during the entie transaction to avoid any
273 	 * reset to the data stream coming from the chip.
274 	 */
275 
276 	for (; rxfc != 0; rxfc--) {
277 		rxstat = ks8851_rdreg16(ks, KS_RXFHSR);
278 		rxlen = ks8851_rdreg16(ks, KS_RXFHBCR) & RXFHBCR_CNT_MASK;
279 
280 		netif_dbg(ks, rx_status, ks->netdev,
281 			  "rx: stat 0x%04x, len 0x%04x\n", rxstat, rxlen);
282 
283 		/* the length of the packet includes the 32bit CRC */
284 
285 		/* set dma read address */
286 		ks8851_wrreg16(ks, KS_RXFDPR, RXFDPR_RXFPAI | 0x00);
287 
288 		/* start DMA access */
289 		ks8851_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr | RXQCR_SDA);
290 
291 		if (rxlen > 4) {
292 			unsigned int rxalign;
293 
294 			rxlen -= 4;
295 			rxalign = ALIGN(rxlen, 4);
296 			skb = netdev_alloc_skb_ip_align(ks->netdev, rxalign);
297 			if (skb) {
298 
299 				/* 4 bytes of status header + 4 bytes of
300 				 * garbage: we put them before ethernet
301 				 * header, so that they are copied,
302 				 * but ignored.
303 				 */
304 
305 				rxpkt = skb_put(skb, rxlen) - 8;
306 
307 				ks->rdfifo(ks, rxpkt, rxalign + 8);
308 
309 				if (netif_msg_pktdata(ks))
310 					ks8851_dbg_dumpkkt(ks, rxpkt);
311 
312 				skb->protocol = eth_type_trans(skb, ks->netdev);
313 				ks8851_rx_skb(ks, skb);
314 
315 				ks->netdev->stats.rx_packets++;
316 				ks->netdev->stats.rx_bytes += rxlen;
317 			}
318 		}
319 
320 		/* end DMA access and dequeue packet */
321 		ks8851_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr | RXQCR_RRXEF);
322 	}
323 }
324 
325 /**
326  * ks8851_irq - IRQ handler for dealing with interrupt requests
327  * @irq: IRQ number
328  * @_ks: cookie
329  *
330  * This handler is invoked when the IRQ line asserts to find out what happened.
331  * As we cannot allow ourselves to sleep in HARDIRQ context, this handler runs
332  * in thread context.
333  *
334  * Read the interrupt status, work out what needs to be done and then clear
335  * any of the interrupts that are not needed.
336  */
337 static irqreturn_t ks8851_irq(int irq, void *_ks)
338 {
339 	struct ks8851_net *ks = _ks;
340 	unsigned handled = 0;
341 	unsigned long flags;
342 	unsigned int status;
343 
344 	ks8851_lock(ks, &flags);
345 
346 	status = ks8851_rdreg16(ks, KS_ISR);
347 
348 	netif_dbg(ks, intr, ks->netdev,
349 		  "%s: status 0x%04x\n", __func__, status);
350 
351 	if (status & IRQ_LCI)
352 		handled |= IRQ_LCI;
353 
354 	if (status & IRQ_LDI) {
355 		u16 pmecr = ks8851_rdreg16(ks, KS_PMECR);
356 		pmecr &= ~PMECR_WKEVT_MASK;
357 		ks8851_wrreg16(ks, KS_PMECR, pmecr | PMECR_WKEVT_LINK);
358 
359 		handled |= IRQ_LDI;
360 	}
361 
362 	if (status & IRQ_RXPSI)
363 		handled |= IRQ_RXPSI;
364 
365 	if (status & IRQ_TXI) {
366 		handled |= IRQ_TXI;
367 
368 		/* no lock here, tx queue should have been stopped */
369 
370 		/* update our idea of how much tx space is available to the
371 		 * system */
372 		ks->tx_space = ks8851_rdreg16(ks, KS_TXMIR);
373 
374 		netif_dbg(ks, intr, ks->netdev,
375 			  "%s: txspace %d\n", __func__, ks->tx_space);
376 	}
377 
378 	if (status & IRQ_RXI)
379 		handled |= IRQ_RXI;
380 
381 	if (status & IRQ_SPIBEI) {
382 		netdev_err(ks->netdev, "%s: spi bus error\n", __func__);
383 		handled |= IRQ_SPIBEI;
384 	}
385 
386 	ks8851_wrreg16(ks, KS_ISR, handled);
387 
388 	if (status & IRQ_RXI) {
389 		/* the datasheet says to disable the rx interrupt during
390 		 * packet read-out, however we're masking the interrupt
391 		 * from the device so do not bother masking just the RX
392 		 * from the device. */
393 
394 		ks8851_rx_pkts(ks);
395 	}
396 
397 	/* if something stopped the rx process, probably due to wanting
398 	 * to change the rx settings, then do something about restarting
399 	 * it. */
400 	if (status & IRQ_RXPSI) {
401 		struct ks8851_rxctrl *rxc = &ks->rxctrl;
402 
403 		/* update the multicast hash table */
404 		ks8851_wrreg16(ks, KS_MAHTR0, rxc->mchash[0]);
405 		ks8851_wrreg16(ks, KS_MAHTR1, rxc->mchash[1]);
406 		ks8851_wrreg16(ks, KS_MAHTR2, rxc->mchash[2]);
407 		ks8851_wrreg16(ks, KS_MAHTR3, rxc->mchash[3]);
408 
409 		ks8851_wrreg16(ks, KS_RXCR2, rxc->rxcr2);
410 		ks8851_wrreg16(ks, KS_RXCR1, rxc->rxcr1);
411 	}
412 
413 	ks8851_unlock(ks, &flags);
414 
415 	if (status & IRQ_LCI)
416 		mii_check_link(&ks->mii);
417 
418 	if (status & IRQ_TXI)
419 		netif_wake_queue(ks->netdev);
420 
421 	return IRQ_HANDLED;
422 }
423 
424 /**
425  * ks8851_flush_tx_work - flush outstanding TX work
426  * @ks: The device state
427  */
428 static void ks8851_flush_tx_work(struct ks8851_net *ks)
429 {
430 	if (ks->flush_tx_work)
431 		ks->flush_tx_work(ks);
432 }
433 
434 /**
435  * ks8851_net_open - open network device
436  * @dev: The network device being opened.
437  *
438  * Called when the network device is marked active, such as a user executing
439  * 'ifconfig up' on the device.
440  */
441 static int ks8851_net_open(struct net_device *dev)
442 {
443 	struct ks8851_net *ks = netdev_priv(dev);
444 	unsigned long flags;
445 	int ret;
446 
447 	ret = request_threaded_irq(dev->irq, NULL, ks8851_irq,
448 				   IRQF_TRIGGER_LOW | IRQF_ONESHOT,
449 				   dev->name, ks);
450 	if (ret < 0) {
451 		netdev_err(dev, "failed to get irq\n");
452 		return ret;
453 	}
454 
455 	/* lock the card, even if we may not actually be doing anything
456 	 * else at the moment */
457 	ks8851_lock(ks, &flags);
458 
459 	netif_dbg(ks, ifup, ks->netdev, "opening\n");
460 
461 	/* bring chip out of any power saving mode it was in */
462 	ks8851_set_powermode(ks, PMECR_PM_NORMAL);
463 
464 	/* issue a soft reset to the RX/TX QMU to put it into a known
465 	 * state. */
466 	ks8851_soft_reset(ks, GRR_QMU);
467 
468 	/* setup transmission parameters */
469 
470 	ks8851_wrreg16(ks, KS_TXCR, (TXCR_TXE | /* enable transmit process */
471 				     TXCR_TXPE | /* pad to min length */
472 				     TXCR_TXCRC | /* add CRC */
473 				     TXCR_TXFCE)); /* enable flow control */
474 
475 	/* auto-increment tx data, reset tx pointer */
476 	ks8851_wrreg16(ks, KS_TXFDPR, TXFDPR_TXFPAI);
477 
478 	/* setup receiver control */
479 
480 	ks8851_wrreg16(ks, KS_RXCR1, (RXCR1_RXPAFMA | /*  from mac filter */
481 				      RXCR1_RXFCE | /* enable flow control */
482 				      RXCR1_RXBE | /* broadcast enable */
483 				      RXCR1_RXUE | /* unicast enable */
484 				      RXCR1_RXE)); /* enable rx block */
485 
486 	/* transfer entire frames out in one go */
487 	ks8851_wrreg16(ks, KS_RXCR2, RXCR2_SRDBL_FRAME);
488 
489 	/* set receive counter timeouts */
490 	ks8851_wrreg16(ks, KS_RXDTTR, 1000); /* 1ms after first frame to IRQ */
491 	ks8851_wrreg16(ks, KS_RXDBCTR, 4096); /* >4Kbytes in buffer to IRQ */
492 	ks8851_wrreg16(ks, KS_RXFCTR, 10);  /* 10 frames to IRQ */
493 
494 	ks->rc_rxqcr = (RXQCR_RXFCTE |  /* IRQ on frame count exceeded */
495 			RXQCR_RXDBCTE | /* IRQ on byte count exceeded */
496 			RXQCR_RXDTTE);  /* IRQ on time exceeded */
497 
498 	ks8851_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr);
499 
500 	/* clear then enable interrupts */
501 	ks8851_wrreg16(ks, KS_ISR, ks->rc_ier);
502 	ks8851_wrreg16(ks, KS_IER, ks->rc_ier);
503 
504 	netif_start_queue(ks->netdev);
505 
506 	netif_dbg(ks, ifup, ks->netdev, "network device up\n");
507 
508 	ks8851_unlock(ks, &flags);
509 	mii_check_link(&ks->mii);
510 	return 0;
511 }
512 
513 /**
514  * ks8851_net_stop - close network device
515  * @dev: The device being closed.
516  *
517  * Called to close down a network device which has been active. Cancell any
518  * work, shutdown the RX and TX process and then place the chip into a low
519  * power state whilst it is not being used.
520  */
521 static int ks8851_net_stop(struct net_device *dev)
522 {
523 	struct ks8851_net *ks = netdev_priv(dev);
524 	unsigned long flags;
525 
526 	netif_info(ks, ifdown, dev, "shutting down\n");
527 
528 	netif_stop_queue(dev);
529 
530 	ks8851_lock(ks, &flags);
531 	/* turn off the IRQs and ack any outstanding */
532 	ks8851_wrreg16(ks, KS_IER, 0x0000);
533 	ks8851_wrreg16(ks, KS_ISR, 0xffff);
534 	ks8851_unlock(ks, &flags);
535 
536 	/* stop any outstanding work */
537 	ks8851_flush_tx_work(ks);
538 	flush_work(&ks->rxctrl_work);
539 
540 	ks8851_lock(ks, &flags);
541 	/* shutdown RX process */
542 	ks8851_wrreg16(ks, KS_RXCR1, 0x0000);
543 
544 	/* shutdown TX process */
545 	ks8851_wrreg16(ks, KS_TXCR, 0x0000);
546 
547 	/* set powermode to soft power down to save power */
548 	ks8851_set_powermode(ks, PMECR_PM_SOFTDOWN);
549 	ks8851_unlock(ks, &flags);
550 
551 	/* ensure any queued tx buffers are dumped */
552 	while (!skb_queue_empty(&ks->txq)) {
553 		struct sk_buff *txb = skb_dequeue(&ks->txq);
554 
555 		netif_dbg(ks, ifdown, ks->netdev,
556 			  "%s: freeing txb %p\n", __func__, txb);
557 
558 		dev_kfree_skb(txb);
559 	}
560 
561 	free_irq(dev->irq, ks);
562 
563 	return 0;
564 }
565 
566 /**
567  * ks8851_start_xmit - transmit packet
568  * @skb: The buffer to transmit
569  * @dev: The device used to transmit the packet.
570  *
571  * Called by the network layer to transmit the @skb. Queue the packet for
572  * the device and schedule the necessary work to transmit the packet when
573  * it is free.
574  *
575  * We do this to firstly avoid sleeping with the network device locked,
576  * and secondly so we can round up more than one packet to transmit which
577  * means we can try and avoid generating too many transmit done interrupts.
578  */
579 static netdev_tx_t ks8851_start_xmit(struct sk_buff *skb,
580 				     struct net_device *dev)
581 {
582 	struct ks8851_net *ks = netdev_priv(dev);
583 
584 	return ks->start_xmit(skb, dev);
585 }
586 
587 /**
588  * ks8851_rxctrl_work - work handler to change rx mode
589  * @work: The work structure this belongs to.
590  *
591  * Lock the device and issue the necessary changes to the receive mode from
592  * the network device layer. This is done so that we can do this without
593  * having to sleep whilst holding the network device lock.
594  *
595  * Since the recommendation from Micrel is that the RXQ is shutdown whilst the
596  * receive parameters are programmed, we issue a write to disable the RXQ and
597  * then wait for the interrupt handler to be triggered once the RXQ shutdown is
598  * complete. The interrupt handler then writes the new values into the chip.
599  */
600 static void ks8851_rxctrl_work(struct work_struct *work)
601 {
602 	struct ks8851_net *ks = container_of(work, struct ks8851_net, rxctrl_work);
603 	unsigned long flags;
604 
605 	ks8851_lock(ks, &flags);
606 
607 	/* need to shutdown RXQ before modifying filter parameters */
608 	ks8851_wrreg16(ks, KS_RXCR1, 0x00);
609 
610 	ks8851_unlock(ks, &flags);
611 }
612 
613 static void ks8851_set_rx_mode(struct net_device *dev)
614 {
615 	struct ks8851_net *ks = netdev_priv(dev);
616 	struct ks8851_rxctrl rxctrl;
617 
618 	memset(&rxctrl, 0, sizeof(rxctrl));
619 
620 	if (dev->flags & IFF_PROMISC) {
621 		/* interface to receive everything */
622 
623 		rxctrl.rxcr1 = RXCR1_RXAE | RXCR1_RXINVF;
624 	} else if (dev->flags & IFF_ALLMULTI) {
625 		/* accept all multicast packets */
626 
627 		rxctrl.rxcr1 = (RXCR1_RXME | RXCR1_RXAE |
628 				RXCR1_RXPAFMA | RXCR1_RXMAFMA);
629 	} else if (dev->flags & IFF_MULTICAST && !netdev_mc_empty(dev)) {
630 		struct netdev_hw_addr *ha;
631 		u32 crc;
632 
633 		/* accept some multicast */
634 
635 		netdev_for_each_mc_addr(ha, dev) {
636 			crc = ether_crc(ETH_ALEN, ha->addr);
637 			crc >>= (32 - 6);  /* get top six bits */
638 
639 			rxctrl.mchash[crc >> 4] |= (1 << (crc & 0xf));
640 		}
641 
642 		rxctrl.rxcr1 = RXCR1_RXME | RXCR1_RXPAFMA;
643 	} else {
644 		/* just accept broadcast / unicast */
645 		rxctrl.rxcr1 = RXCR1_RXPAFMA;
646 	}
647 
648 	rxctrl.rxcr1 |= (RXCR1_RXUE | /* unicast enable */
649 			 RXCR1_RXBE | /* broadcast enable */
650 			 RXCR1_RXE | /* RX process enable */
651 			 RXCR1_RXFCE); /* enable flow control */
652 
653 	rxctrl.rxcr2 |= RXCR2_SRDBL_FRAME;
654 
655 	/* schedule work to do the actual set of the data if needed */
656 
657 	spin_lock(&ks->statelock);
658 
659 	if (memcmp(&rxctrl, &ks->rxctrl, sizeof(rxctrl)) != 0) {
660 		memcpy(&ks->rxctrl, &rxctrl, sizeof(ks->rxctrl));
661 		schedule_work(&ks->rxctrl_work);
662 	}
663 
664 	spin_unlock(&ks->statelock);
665 }
666 
667 static int ks8851_set_mac_address(struct net_device *dev, void *addr)
668 {
669 	struct sockaddr *sa = addr;
670 
671 	if (netif_running(dev))
672 		return -EBUSY;
673 
674 	if (!is_valid_ether_addr(sa->sa_data))
675 		return -EADDRNOTAVAIL;
676 
677 	memcpy(dev->dev_addr, sa->sa_data, ETH_ALEN);
678 	return ks8851_write_mac_addr(dev);
679 }
680 
681 static int ks8851_net_ioctl(struct net_device *dev, struct ifreq *req, int cmd)
682 {
683 	struct ks8851_net *ks = netdev_priv(dev);
684 
685 	if (!netif_running(dev))
686 		return -EINVAL;
687 
688 	return generic_mii_ioctl(&ks->mii, if_mii(req), cmd, NULL);
689 }
690 
691 static const struct net_device_ops ks8851_netdev_ops = {
692 	.ndo_open		= ks8851_net_open,
693 	.ndo_stop		= ks8851_net_stop,
694 	.ndo_do_ioctl		= ks8851_net_ioctl,
695 	.ndo_start_xmit		= ks8851_start_xmit,
696 	.ndo_set_mac_address	= ks8851_set_mac_address,
697 	.ndo_set_rx_mode	= ks8851_set_rx_mode,
698 	.ndo_validate_addr	= eth_validate_addr,
699 };
700 
701 /* ethtool support */
702 
703 static void ks8851_get_drvinfo(struct net_device *dev,
704 			       struct ethtool_drvinfo *di)
705 {
706 	strlcpy(di->driver, "KS8851", sizeof(di->driver));
707 	strlcpy(di->version, "1.00", sizeof(di->version));
708 	strlcpy(di->bus_info, dev_name(dev->dev.parent), sizeof(di->bus_info));
709 }
710 
711 static u32 ks8851_get_msglevel(struct net_device *dev)
712 {
713 	struct ks8851_net *ks = netdev_priv(dev);
714 	return ks->msg_enable;
715 }
716 
717 static void ks8851_set_msglevel(struct net_device *dev, u32 to)
718 {
719 	struct ks8851_net *ks = netdev_priv(dev);
720 	ks->msg_enable = to;
721 }
722 
723 static int ks8851_get_link_ksettings(struct net_device *dev,
724 				     struct ethtool_link_ksettings *cmd)
725 {
726 	struct ks8851_net *ks = netdev_priv(dev);
727 
728 	mii_ethtool_get_link_ksettings(&ks->mii, cmd);
729 
730 	return 0;
731 }
732 
733 static int ks8851_set_link_ksettings(struct net_device *dev,
734 				     const struct ethtool_link_ksettings *cmd)
735 {
736 	struct ks8851_net *ks = netdev_priv(dev);
737 	return mii_ethtool_set_link_ksettings(&ks->mii, cmd);
738 }
739 
740 static u32 ks8851_get_link(struct net_device *dev)
741 {
742 	struct ks8851_net *ks = netdev_priv(dev);
743 	return mii_link_ok(&ks->mii);
744 }
745 
746 static int ks8851_nway_reset(struct net_device *dev)
747 {
748 	struct ks8851_net *ks = netdev_priv(dev);
749 	return mii_nway_restart(&ks->mii);
750 }
751 
752 /* EEPROM support */
753 
754 static void ks8851_eeprom_regread(struct eeprom_93cx6 *ee)
755 {
756 	struct ks8851_net *ks = ee->data;
757 	unsigned val;
758 
759 	val = ks8851_rdreg16(ks, KS_EEPCR);
760 
761 	ee->reg_data_out = (val & EEPCR_EESB) ? 1 : 0;
762 	ee->reg_data_clock = (val & EEPCR_EESCK) ? 1 : 0;
763 	ee->reg_chip_select = (val & EEPCR_EECS) ? 1 : 0;
764 }
765 
766 static void ks8851_eeprom_regwrite(struct eeprom_93cx6 *ee)
767 {
768 	struct ks8851_net *ks = ee->data;
769 	unsigned val = EEPCR_EESA;	/* default - eeprom access on */
770 
771 	if (ee->drive_data)
772 		val |= EEPCR_EESRWA;
773 	if (ee->reg_data_in)
774 		val |= EEPCR_EEDO;
775 	if (ee->reg_data_clock)
776 		val |= EEPCR_EESCK;
777 	if (ee->reg_chip_select)
778 		val |= EEPCR_EECS;
779 
780 	ks8851_wrreg16(ks, KS_EEPCR, val);
781 }
782 
783 /**
784  * ks8851_eeprom_claim - claim device EEPROM and activate the interface
785  * @ks: The network device state.
786  *
787  * Check for the presence of an EEPROM, and then activate software access
788  * to the device.
789  */
790 static int ks8851_eeprom_claim(struct ks8851_net *ks)
791 {
792 	/* start with clock low, cs high */
793 	ks8851_wrreg16(ks, KS_EEPCR, EEPCR_EESA | EEPCR_EECS);
794 	return 0;
795 }
796 
797 /**
798  * ks8851_eeprom_release - release the EEPROM interface
799  * @ks: The device state
800  *
801  * Release the software access to the device EEPROM
802  */
803 static void ks8851_eeprom_release(struct ks8851_net *ks)
804 {
805 	unsigned val = ks8851_rdreg16(ks, KS_EEPCR);
806 
807 	ks8851_wrreg16(ks, KS_EEPCR, val & ~EEPCR_EESA);
808 }
809 
810 #define KS_EEPROM_MAGIC (0x00008851)
811 
812 static int ks8851_set_eeprom(struct net_device *dev,
813 			     struct ethtool_eeprom *ee, u8 *data)
814 {
815 	struct ks8851_net *ks = netdev_priv(dev);
816 	int offset = ee->offset;
817 	unsigned long flags;
818 	int len = ee->len;
819 	u16 tmp;
820 
821 	/* currently only support byte writing */
822 	if (len != 1)
823 		return -EINVAL;
824 
825 	if (ee->magic != KS_EEPROM_MAGIC)
826 		return -EINVAL;
827 
828 	if (!(ks->rc_ccr & CCR_EEPROM))
829 		return -ENOENT;
830 
831 	ks8851_lock(ks, &flags);
832 
833 	ks8851_eeprom_claim(ks);
834 
835 	eeprom_93cx6_wren(&ks->eeprom, true);
836 
837 	/* ethtool currently only supports writing bytes, which means
838 	 * we have to read/modify/write our 16bit EEPROMs */
839 
840 	eeprom_93cx6_read(&ks->eeprom, offset/2, &tmp);
841 
842 	if (offset & 1) {
843 		tmp &= 0xff;
844 		tmp |= *data << 8;
845 	} else {
846 		tmp &= 0xff00;
847 		tmp |= *data;
848 	}
849 
850 	eeprom_93cx6_write(&ks->eeprom, offset/2, tmp);
851 	eeprom_93cx6_wren(&ks->eeprom, false);
852 
853 	ks8851_eeprom_release(ks);
854 	ks8851_unlock(ks, &flags);
855 
856 	return 0;
857 }
858 
859 static int ks8851_get_eeprom(struct net_device *dev,
860 			     struct ethtool_eeprom *ee, u8 *data)
861 {
862 	struct ks8851_net *ks = netdev_priv(dev);
863 	int offset = ee->offset;
864 	unsigned long flags;
865 	int len = ee->len;
866 
867 	/* must be 2 byte aligned */
868 	if (len & 1 || offset & 1)
869 		return -EINVAL;
870 
871 	if (!(ks->rc_ccr & CCR_EEPROM))
872 		return -ENOENT;
873 
874 	ks8851_lock(ks, &flags);
875 
876 	ks8851_eeprom_claim(ks);
877 
878 	ee->magic = KS_EEPROM_MAGIC;
879 
880 	eeprom_93cx6_multiread(&ks->eeprom, offset/2, (__le16 *)data, len/2);
881 	ks8851_eeprom_release(ks);
882 	ks8851_unlock(ks, &flags);
883 
884 	return 0;
885 }
886 
887 static int ks8851_get_eeprom_len(struct net_device *dev)
888 {
889 	struct ks8851_net *ks = netdev_priv(dev);
890 
891 	/* currently, we assume it is an 93C46 attached, so return 128 */
892 	return ks->rc_ccr & CCR_EEPROM ? 128 : 0;
893 }
894 
895 static const struct ethtool_ops ks8851_ethtool_ops = {
896 	.get_drvinfo	= ks8851_get_drvinfo,
897 	.get_msglevel	= ks8851_get_msglevel,
898 	.set_msglevel	= ks8851_set_msglevel,
899 	.get_link	= ks8851_get_link,
900 	.nway_reset	= ks8851_nway_reset,
901 	.get_eeprom_len	= ks8851_get_eeprom_len,
902 	.get_eeprom	= ks8851_get_eeprom,
903 	.set_eeprom	= ks8851_set_eeprom,
904 	.get_link_ksettings = ks8851_get_link_ksettings,
905 	.set_link_ksettings = ks8851_set_link_ksettings,
906 };
907 
908 /* MII interface controls */
909 
910 /**
911  * ks8851_phy_reg - convert MII register into a KS8851 register
912  * @reg: MII register number.
913  *
914  * Return the KS8851 register number for the corresponding MII PHY register
915  * if possible. Return zero if the MII register has no direct mapping to the
916  * KS8851 register set.
917  */
918 static int ks8851_phy_reg(int reg)
919 {
920 	switch (reg) {
921 	case MII_BMCR:
922 		return KS_P1MBCR;
923 	case MII_BMSR:
924 		return KS_P1MBSR;
925 	case MII_PHYSID1:
926 		return KS_PHY1ILR;
927 	case MII_PHYSID2:
928 		return KS_PHY1IHR;
929 	case MII_ADVERTISE:
930 		return KS_P1ANAR;
931 	case MII_LPA:
932 		return KS_P1ANLPR;
933 	}
934 
935 	return 0x0;
936 }
937 
938 /**
939  * ks8851_phy_read - MII interface PHY register read.
940  * @dev: The network device the PHY is on.
941  * @phy_addr: Address of PHY (ignored as we only have one)
942  * @reg: The register to read.
943  *
944  * This call reads data from the PHY register specified in @reg. Since the
945  * device does not support all the MII registers, the non-existent values
946  * are always returned as zero.
947  *
948  * We return zero for unsupported registers as the MII code does not check
949  * the value returned for any error status, and simply returns it to the
950  * caller. The mii-tool that the driver was tested with takes any -ve error
951  * as real PHY capabilities, thus displaying incorrect data to the user.
952  */
953 static int ks8851_phy_read(struct net_device *dev, int phy_addr, int reg)
954 {
955 	struct ks8851_net *ks = netdev_priv(dev);
956 	unsigned long flags;
957 	int ksreg;
958 	int result;
959 
960 	ksreg = ks8851_phy_reg(reg);
961 	if (!ksreg)
962 		return 0x0;	/* no error return allowed, so use zero */
963 
964 	ks8851_lock(ks, &flags);
965 	result = ks8851_rdreg16(ks, ksreg);
966 	ks8851_unlock(ks, &flags);
967 
968 	return result;
969 }
970 
971 static void ks8851_phy_write(struct net_device *dev,
972 			     int phy, int reg, int value)
973 {
974 	struct ks8851_net *ks = netdev_priv(dev);
975 	unsigned long flags;
976 	int ksreg;
977 
978 	ksreg = ks8851_phy_reg(reg);
979 	if (ksreg) {
980 		ks8851_lock(ks, &flags);
981 		ks8851_wrreg16(ks, ksreg, value);
982 		ks8851_unlock(ks, &flags);
983 	}
984 }
985 
986 /**
987  * ks8851_read_selftest - read the selftest memory info.
988  * @ks: The device state
989  *
990  * Read and check the TX/RX memory selftest information.
991  */
992 static int ks8851_read_selftest(struct ks8851_net *ks)
993 {
994 	unsigned both_done = MBIR_TXMBF | MBIR_RXMBF;
995 	int ret = 0;
996 	unsigned rd;
997 
998 	rd = ks8851_rdreg16(ks, KS_MBIR);
999 
1000 	if ((rd & both_done) != both_done) {
1001 		netdev_warn(ks->netdev, "Memory selftest not finished\n");
1002 		return 0;
1003 	}
1004 
1005 	if (rd & MBIR_TXMBFA) {
1006 		netdev_err(ks->netdev, "TX memory selftest fail\n");
1007 		ret |= 1;
1008 	}
1009 
1010 	if (rd & MBIR_RXMBFA) {
1011 		netdev_err(ks->netdev, "RX memory selftest fail\n");
1012 		ret |= 2;
1013 	}
1014 
1015 	return 0;
1016 }
1017 
1018 /* driver bus management functions */
1019 
1020 #ifdef CONFIG_PM_SLEEP
1021 
1022 int ks8851_suspend(struct device *dev)
1023 {
1024 	struct ks8851_net *ks = dev_get_drvdata(dev);
1025 	struct net_device *netdev = ks->netdev;
1026 
1027 	if (netif_running(netdev)) {
1028 		netif_device_detach(netdev);
1029 		ks8851_net_stop(netdev);
1030 	}
1031 
1032 	return 0;
1033 }
1034 
1035 int ks8851_resume(struct device *dev)
1036 {
1037 	struct ks8851_net *ks = dev_get_drvdata(dev);
1038 	struct net_device *netdev = ks->netdev;
1039 
1040 	if (netif_running(netdev)) {
1041 		ks8851_net_open(netdev);
1042 		netif_device_attach(netdev);
1043 	}
1044 
1045 	return 0;
1046 }
1047 #endif
1048 
1049 int ks8851_probe_common(struct net_device *netdev, struct device *dev,
1050 			int msg_en)
1051 {
1052 	struct ks8851_net *ks = netdev_priv(netdev);
1053 	unsigned cider;
1054 	int gpio;
1055 	int ret;
1056 
1057 	ks->netdev = netdev;
1058 	ks->tx_space = 6144;
1059 
1060 	gpio = of_get_named_gpio_flags(dev->of_node, "reset-gpios", 0, NULL);
1061 	if (gpio == -EPROBE_DEFER)
1062 		return gpio;
1063 
1064 	ks->gpio = gpio;
1065 	if (gpio_is_valid(gpio)) {
1066 		ret = devm_gpio_request_one(dev, gpio,
1067 					    GPIOF_OUT_INIT_LOW, "ks8851_rst_n");
1068 		if (ret) {
1069 			dev_err(dev, "reset gpio request failed\n");
1070 			return ret;
1071 		}
1072 	}
1073 
1074 	ks->vdd_io = devm_regulator_get(dev, "vdd-io");
1075 	if (IS_ERR(ks->vdd_io)) {
1076 		ret = PTR_ERR(ks->vdd_io);
1077 		goto err_reg_io;
1078 	}
1079 
1080 	ret = regulator_enable(ks->vdd_io);
1081 	if (ret) {
1082 		dev_err(dev, "regulator vdd_io enable fail: %d\n", ret);
1083 		goto err_reg_io;
1084 	}
1085 
1086 	ks->vdd_reg = devm_regulator_get(dev, "vdd");
1087 	if (IS_ERR(ks->vdd_reg)) {
1088 		ret = PTR_ERR(ks->vdd_reg);
1089 		goto err_reg;
1090 	}
1091 
1092 	ret = regulator_enable(ks->vdd_reg);
1093 	if (ret) {
1094 		dev_err(dev, "regulator vdd enable fail: %d\n", ret);
1095 		goto err_reg;
1096 	}
1097 
1098 	if (gpio_is_valid(gpio)) {
1099 		usleep_range(10000, 11000);
1100 		gpio_set_value(gpio, 1);
1101 	}
1102 
1103 	spin_lock_init(&ks->statelock);
1104 
1105 	INIT_WORK(&ks->rxctrl_work, ks8851_rxctrl_work);
1106 
1107 	/* setup EEPROM state */
1108 	ks->eeprom.data = ks;
1109 	ks->eeprom.width = PCI_EEPROM_WIDTH_93C46;
1110 	ks->eeprom.register_read = ks8851_eeprom_regread;
1111 	ks->eeprom.register_write = ks8851_eeprom_regwrite;
1112 
1113 	/* setup mii state */
1114 	ks->mii.dev		= netdev;
1115 	ks->mii.phy_id		= 1,
1116 	ks->mii.phy_id_mask	= 1;
1117 	ks->mii.reg_num_mask	= 0xf;
1118 	ks->mii.mdio_read	= ks8851_phy_read;
1119 	ks->mii.mdio_write	= ks8851_phy_write;
1120 
1121 	dev_info(dev, "message enable is %d\n", msg_en);
1122 
1123 	/* set the default message enable */
1124 	ks->msg_enable = netif_msg_init(msg_en, NETIF_MSG_DRV |
1125 						NETIF_MSG_PROBE |
1126 						NETIF_MSG_LINK);
1127 
1128 	skb_queue_head_init(&ks->txq);
1129 
1130 	netdev->ethtool_ops = &ks8851_ethtool_ops;
1131 	SET_NETDEV_DEV(netdev, dev);
1132 
1133 	dev_set_drvdata(dev, ks);
1134 
1135 	netif_carrier_off(ks->netdev);
1136 	netdev->if_port = IF_PORT_100BASET;
1137 	netdev->netdev_ops = &ks8851_netdev_ops;
1138 
1139 	/* issue a global soft reset to reset the device. */
1140 	ks8851_soft_reset(ks, GRR_GSR);
1141 
1142 	/* simple check for a valid chip being connected to the bus */
1143 	cider = ks8851_rdreg16(ks, KS_CIDER);
1144 	if ((cider & ~CIDER_REV_MASK) != CIDER_ID) {
1145 		dev_err(dev, "failed to read device ID\n");
1146 		ret = -ENODEV;
1147 		goto err_id;
1148 	}
1149 
1150 	/* cache the contents of the CCR register for EEPROM, etc. */
1151 	ks->rc_ccr = ks8851_rdreg16(ks, KS_CCR);
1152 
1153 	ks8851_read_selftest(ks);
1154 	ks8851_init_mac(ks, dev->of_node);
1155 
1156 	ret = register_netdev(netdev);
1157 	if (ret) {
1158 		dev_err(dev, "failed to register network device\n");
1159 		goto err_netdev;
1160 	}
1161 
1162 	netdev_info(netdev, "revision %d, MAC %pM, IRQ %d, %s EEPROM\n",
1163 		    CIDER_REV_GET(cider), netdev->dev_addr, netdev->irq,
1164 		    ks->rc_ccr & CCR_EEPROM ? "has" : "no");
1165 
1166 	return 0;
1167 
1168 err_netdev:
1169 err_id:
1170 	if (gpio_is_valid(gpio))
1171 		gpio_set_value(gpio, 0);
1172 	regulator_disable(ks->vdd_reg);
1173 err_reg:
1174 	regulator_disable(ks->vdd_io);
1175 err_reg_io:
1176 	return ret;
1177 }
1178 
1179 int ks8851_remove_common(struct device *dev)
1180 {
1181 	struct ks8851_net *priv = dev_get_drvdata(dev);
1182 
1183 	if (netif_msg_drv(priv))
1184 		dev_info(dev, "remove\n");
1185 
1186 	unregister_netdev(priv->netdev);
1187 	if (gpio_is_valid(priv->gpio))
1188 		gpio_set_value(priv->gpio, 0);
1189 	regulator_disable(priv->vdd_reg);
1190 	regulator_disable(priv->vdd_io);
1191 
1192 	return 0;
1193 }
1194