xref: /openbmc/linux/drivers/net/ethernet/korina.c (revision 6f4eaea2)
1 /*
2  *  Driver for the IDT RC32434 (Korina) on-chip ethernet controller.
3  *
4  *  Copyright 2004 IDT Inc. (rischelp@idt.com)
5  *  Copyright 2006 Felix Fietkau <nbd@openwrt.org>
6  *  Copyright 2008 Florian Fainelli <florian@openwrt.org>
7  *  Copyright 2017 Roman Yeryomin <roman@advem.lv>
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
15  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
16  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
17  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
18  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
20  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
21  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
22  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  *  You should have received a copy of the  GNU General Public License along
26  *  with this program; if not, write  to the Free Software Foundation, Inc.,
27  *  675 Mass Ave, Cambridge, MA 02139, USA.
28  *
29  *  Writing to a DMA status register:
30  *
31  *  When writing to the status register, you should mask the bit you have
32  *  been testing the status register with. Both Tx and Rx DMA registers
33  *  should stick to this procedure.
34  */
35 
36 #include <linux/module.h>
37 #include <linux/kernel.h>
38 #include <linux/moduleparam.h>
39 #include <linux/sched.h>
40 #include <linux/ctype.h>
41 #include <linux/types.h>
42 #include <linux/interrupt.h>
43 #include <linux/ioport.h>
44 #include <linux/in.h>
45 #include <linux/slab.h>
46 #include <linux/string.h>
47 #include <linux/delay.h>
48 #include <linux/netdevice.h>
49 #include <linux/etherdevice.h>
50 #include <linux/skbuff.h>
51 #include <linux/errno.h>
52 #include <linux/platform_device.h>
53 #include <linux/mii.h>
54 #include <linux/ethtool.h>
55 #include <linux/crc32.h>
56 #include <linux/pgtable.h>
57 
58 #include <asm/bootinfo.h>
59 #include <asm/bitops.h>
60 #include <asm/io.h>
61 #include <asm/dma.h>
62 
63 #include <asm/mach-rc32434/rb.h>
64 #include <asm/mach-rc32434/rc32434.h>
65 #include <asm/mach-rc32434/eth.h>
66 #include <asm/mach-rc32434/dma_v.h>
67 
68 #define DRV_NAME	"korina"
69 #define DRV_VERSION	"0.20"
70 #define DRV_RELDATE	"15Sep2017"
71 
72 #define STATION_ADDRESS_HIGH(dev) (((dev)->dev_addr[0] << 8) | \
73 				   ((dev)->dev_addr[1]))
74 #define STATION_ADDRESS_LOW(dev)  (((dev)->dev_addr[2] << 24) | \
75 				   ((dev)->dev_addr[3] << 16) | \
76 				   ((dev)->dev_addr[4] << 8)  | \
77 				   ((dev)->dev_addr[5]))
78 
79 #define MII_CLOCK	1250000 /* no more than 2.5MHz */
80 
81 /* the following must be powers of two */
82 #define KORINA_NUM_RDS	64  /* number of receive descriptors */
83 #define KORINA_NUM_TDS	64  /* number of transmit descriptors */
84 
85 /* KORINA_RBSIZE is the hardware's default maximum receive
86  * frame size in bytes. Having this hardcoded means that there
87  * is no support for MTU sizes greater than 1500. */
88 #define KORINA_RBSIZE	1536 /* size of one resource buffer = Ether MTU */
89 #define KORINA_RDS_MASK	(KORINA_NUM_RDS - 1)
90 #define KORINA_TDS_MASK	(KORINA_NUM_TDS - 1)
91 #define RD_RING_SIZE	(KORINA_NUM_RDS * sizeof(struct dma_desc))
92 #define TD_RING_SIZE	(KORINA_NUM_TDS * sizeof(struct dma_desc))
93 
94 #define TX_TIMEOUT	(6000 * HZ / 1000)
95 
96 enum chain_status {
97 	desc_filled,
98 	desc_empty
99 };
100 
101 #define IS_DMA_FINISHED(X)	(((X) & (DMA_DESC_FINI)) != 0)
102 #define IS_DMA_DONE(X)		(((X) & (DMA_DESC_DONE)) != 0)
103 #define RCVPKT_LENGTH(X)	(((X) & ETH_RX_LEN) >> ETH_RX_LEN_BIT)
104 
105 /* Information that need to be kept for each board. */
106 struct korina_private {
107 	struct eth_regs *eth_regs;
108 	struct dma_reg *rx_dma_regs;
109 	struct dma_reg *tx_dma_regs;
110 	struct dma_desc *td_ring; /* transmit descriptor ring */
111 	struct dma_desc *rd_ring; /* receive descriptor ring  */
112 
113 	struct sk_buff *tx_skb[KORINA_NUM_TDS];
114 	struct sk_buff *rx_skb[KORINA_NUM_RDS];
115 
116 	int rx_next_done;
117 	int rx_chain_head;
118 	int rx_chain_tail;
119 	enum chain_status rx_chain_status;
120 
121 	int tx_next_done;
122 	int tx_chain_head;
123 	int tx_chain_tail;
124 	enum chain_status tx_chain_status;
125 	int tx_count;
126 	int tx_full;
127 
128 	int rx_irq;
129 	int tx_irq;
130 
131 	spinlock_t lock;	/* NIC xmit lock */
132 
133 	int dma_halt_cnt;
134 	int dma_run_cnt;
135 	struct napi_struct napi;
136 	struct timer_list media_check_timer;
137 	struct mii_if_info mii_if;
138 	struct work_struct restart_task;
139 	struct net_device *dev;
140 	int phy_addr;
141 };
142 
143 extern unsigned int idt_cpu_freq;
144 
145 static inline void korina_start_dma(struct dma_reg *ch, u32 dma_addr)
146 {
147 	writel(0, &ch->dmandptr);
148 	writel(dma_addr, &ch->dmadptr);
149 }
150 
151 static inline void korina_abort_dma(struct net_device *dev,
152 					struct dma_reg *ch)
153 {
154 	if (readl(&ch->dmac) & DMA_CHAN_RUN_BIT) {
155 		writel(0x10, &ch->dmac);
156 
157 		while (!(readl(&ch->dmas) & DMA_STAT_HALT))
158 			netif_trans_update(dev);
159 
160 		writel(0, &ch->dmas);
161 	}
162 
163 	writel(0, &ch->dmadptr);
164 	writel(0, &ch->dmandptr);
165 }
166 
167 static inline void korina_chain_dma(struct dma_reg *ch, u32 dma_addr)
168 {
169 	writel(dma_addr, &ch->dmandptr);
170 }
171 
172 static void korina_abort_tx(struct net_device *dev)
173 {
174 	struct korina_private *lp = netdev_priv(dev);
175 
176 	korina_abort_dma(dev, lp->tx_dma_regs);
177 }
178 
179 static void korina_abort_rx(struct net_device *dev)
180 {
181 	struct korina_private *lp = netdev_priv(dev);
182 
183 	korina_abort_dma(dev, lp->rx_dma_regs);
184 }
185 
186 static void korina_start_rx(struct korina_private *lp,
187 					struct dma_desc *rd)
188 {
189 	korina_start_dma(lp->rx_dma_regs, CPHYSADDR(rd));
190 }
191 
192 static void korina_chain_rx(struct korina_private *lp,
193 					struct dma_desc *rd)
194 {
195 	korina_chain_dma(lp->rx_dma_regs, CPHYSADDR(rd));
196 }
197 
198 /* transmit packet */
199 static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
200 {
201 	struct korina_private *lp = netdev_priv(dev);
202 	unsigned long flags;
203 	u32 length;
204 	u32 chain_prev, chain_next;
205 	struct dma_desc *td;
206 
207 	spin_lock_irqsave(&lp->lock, flags);
208 
209 	td = &lp->td_ring[lp->tx_chain_tail];
210 
211 	/* stop queue when full, drop pkts if queue already full */
212 	if (lp->tx_count >= (KORINA_NUM_TDS - 2)) {
213 		lp->tx_full = 1;
214 
215 		if (lp->tx_count == (KORINA_NUM_TDS - 2))
216 			netif_stop_queue(dev);
217 		else {
218 			dev->stats.tx_dropped++;
219 			dev_kfree_skb_any(skb);
220 			spin_unlock_irqrestore(&lp->lock, flags);
221 
222 			return NETDEV_TX_OK;
223 		}
224 	}
225 
226 	lp->tx_count++;
227 
228 	lp->tx_skb[lp->tx_chain_tail] = skb;
229 
230 	length = skb->len;
231 	dma_cache_wback((u32)skb->data, skb->len);
232 
233 	/* Setup the transmit descriptor. */
234 	dma_cache_inv((u32) td, sizeof(*td));
235 	td->ca = CPHYSADDR(skb->data);
236 	chain_prev = (lp->tx_chain_tail - 1) & KORINA_TDS_MASK;
237 	chain_next = (lp->tx_chain_tail + 1) & KORINA_TDS_MASK;
238 
239 	if (readl(&(lp->tx_dma_regs->dmandptr)) == 0) {
240 		if (lp->tx_chain_status == desc_empty) {
241 			/* Update tail */
242 			td->control = DMA_COUNT(length) |
243 					DMA_DESC_COF | DMA_DESC_IOF;
244 			/* Move tail */
245 			lp->tx_chain_tail = chain_next;
246 			/* Write to NDPTR */
247 			writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
248 					&lp->tx_dma_regs->dmandptr);
249 			/* Move head to tail */
250 			lp->tx_chain_head = lp->tx_chain_tail;
251 		} else {
252 			/* Update tail */
253 			td->control = DMA_COUNT(length) |
254 					DMA_DESC_COF | DMA_DESC_IOF;
255 			/* Link to prev */
256 			lp->td_ring[chain_prev].control &=
257 					~DMA_DESC_COF;
258 			/* Link to prev */
259 			lp->td_ring[chain_prev].link =  CPHYSADDR(td);
260 			/* Move tail */
261 			lp->tx_chain_tail = chain_next;
262 			/* Write to NDPTR */
263 			writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
264 					&(lp->tx_dma_regs->dmandptr));
265 			/* Move head to tail */
266 			lp->tx_chain_head = lp->tx_chain_tail;
267 			lp->tx_chain_status = desc_empty;
268 		}
269 	} else {
270 		if (lp->tx_chain_status == desc_empty) {
271 			/* Update tail */
272 			td->control = DMA_COUNT(length) |
273 					DMA_DESC_COF | DMA_DESC_IOF;
274 			/* Move tail */
275 			lp->tx_chain_tail = chain_next;
276 			lp->tx_chain_status = desc_filled;
277 		} else {
278 			/* Update tail */
279 			td->control = DMA_COUNT(length) |
280 					DMA_DESC_COF | DMA_DESC_IOF;
281 			lp->td_ring[chain_prev].control &=
282 					~DMA_DESC_COF;
283 			lp->td_ring[chain_prev].link =  CPHYSADDR(td);
284 			lp->tx_chain_tail = chain_next;
285 		}
286 	}
287 	dma_cache_wback((u32) td, sizeof(*td));
288 
289 	netif_trans_update(dev);
290 	spin_unlock_irqrestore(&lp->lock, flags);
291 
292 	return NETDEV_TX_OK;
293 }
294 
295 static int mdio_read(struct net_device *dev, int mii_id, int reg)
296 {
297 	struct korina_private *lp = netdev_priv(dev);
298 	int ret;
299 
300 	mii_id = ((lp->rx_irq == 0x2c ? 1 : 0) << 8);
301 
302 	writel(0, &lp->eth_regs->miimcfg);
303 	writel(0, &lp->eth_regs->miimcmd);
304 	writel(mii_id | reg, &lp->eth_regs->miimaddr);
305 	writel(ETH_MII_CMD_SCN, &lp->eth_regs->miimcmd);
306 
307 	ret = (int)(readl(&lp->eth_regs->miimrdd));
308 	return ret;
309 }
310 
311 static void mdio_write(struct net_device *dev, int mii_id, int reg, int val)
312 {
313 	struct korina_private *lp = netdev_priv(dev);
314 
315 	mii_id = ((lp->rx_irq == 0x2c ? 1 : 0) << 8);
316 
317 	writel(0, &lp->eth_regs->miimcfg);
318 	writel(1, &lp->eth_regs->miimcmd);
319 	writel(mii_id | reg, &lp->eth_regs->miimaddr);
320 	writel(ETH_MII_CMD_SCN, &lp->eth_regs->miimcmd);
321 	writel(val, &lp->eth_regs->miimwtd);
322 }
323 
324 /* Ethernet Rx DMA interrupt */
325 static irqreturn_t korina_rx_dma_interrupt(int irq, void *dev_id)
326 {
327 	struct net_device *dev = dev_id;
328 	struct korina_private *lp = netdev_priv(dev);
329 	u32 dmas, dmasm;
330 	irqreturn_t retval;
331 
332 	dmas = readl(&lp->rx_dma_regs->dmas);
333 	if (dmas & (DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR)) {
334 		dmasm = readl(&lp->rx_dma_regs->dmasm);
335 		writel(dmasm | (DMA_STAT_DONE |
336 				DMA_STAT_HALT | DMA_STAT_ERR),
337 				&lp->rx_dma_regs->dmasm);
338 
339 		napi_schedule(&lp->napi);
340 
341 		if (dmas & DMA_STAT_ERR)
342 			printk(KERN_ERR "%s: DMA error\n", dev->name);
343 
344 		retval = IRQ_HANDLED;
345 	} else
346 		retval = IRQ_NONE;
347 
348 	return retval;
349 }
350 
351 static int korina_rx(struct net_device *dev, int limit)
352 {
353 	struct korina_private *lp = netdev_priv(dev);
354 	struct dma_desc *rd = &lp->rd_ring[lp->rx_next_done];
355 	struct sk_buff *skb, *skb_new;
356 	u8 *pkt_buf;
357 	u32 devcs, pkt_len, dmas;
358 	int count;
359 
360 	dma_cache_inv((u32)rd, sizeof(*rd));
361 
362 	for (count = 0; count < limit; count++) {
363 		skb = lp->rx_skb[lp->rx_next_done];
364 		skb_new = NULL;
365 
366 		devcs = rd->devcs;
367 
368 		if ((KORINA_RBSIZE - (u32)DMA_COUNT(rd->control)) == 0)
369 			break;
370 
371 		/* check that this is a whole packet
372 		 * WARNING: DMA_FD bit incorrectly set
373 		 * in Rc32434 (errata ref #077) */
374 		if (!(devcs & ETH_RX_LD))
375 			goto next;
376 
377 		if (!(devcs & ETH_RX_ROK)) {
378 			/* Update statistics counters */
379 			dev->stats.rx_errors++;
380 			dev->stats.rx_dropped++;
381 			if (devcs & ETH_RX_CRC)
382 				dev->stats.rx_crc_errors++;
383 			if (devcs & ETH_RX_LE)
384 				dev->stats.rx_length_errors++;
385 			if (devcs & ETH_RX_OVR)
386 				dev->stats.rx_fifo_errors++;
387 			if (devcs & ETH_RX_CV)
388 				dev->stats.rx_frame_errors++;
389 			if (devcs & ETH_RX_CES)
390 				dev->stats.rx_frame_errors++;
391 
392 			goto next;
393 		}
394 
395 		pkt_len = RCVPKT_LENGTH(devcs);
396 
397 		/* must be the (first and) last
398 		 * descriptor then */
399 		pkt_buf = (u8 *)lp->rx_skb[lp->rx_next_done]->data;
400 
401 		/* invalidate the cache */
402 		dma_cache_inv((unsigned long)pkt_buf, pkt_len - 4);
403 
404 		/* Malloc up new buffer. */
405 		skb_new = netdev_alloc_skb_ip_align(dev, KORINA_RBSIZE);
406 
407 		if (!skb_new)
408 			break;
409 		/* Do not count the CRC */
410 		skb_put(skb, pkt_len - 4);
411 		skb->protocol = eth_type_trans(skb, dev);
412 
413 		/* Pass the packet to upper layers */
414 		napi_gro_receive(&lp->napi, skb);
415 		dev->stats.rx_packets++;
416 		dev->stats.rx_bytes += pkt_len;
417 
418 		/* Update the mcast stats */
419 		if (devcs & ETH_RX_MP)
420 			dev->stats.multicast++;
421 
422 		lp->rx_skb[lp->rx_next_done] = skb_new;
423 
424 next:
425 		rd->devcs = 0;
426 
427 		/* Restore descriptor's curr_addr */
428 		if (skb_new)
429 			rd->ca = CPHYSADDR(skb_new->data);
430 		else
431 			rd->ca = CPHYSADDR(skb->data);
432 
433 		rd->control = DMA_COUNT(KORINA_RBSIZE) |
434 			DMA_DESC_COD | DMA_DESC_IOD;
435 		lp->rd_ring[(lp->rx_next_done - 1) &
436 			KORINA_RDS_MASK].control &=
437 			~DMA_DESC_COD;
438 
439 		lp->rx_next_done = (lp->rx_next_done + 1) & KORINA_RDS_MASK;
440 		dma_cache_wback((u32)rd, sizeof(*rd));
441 		rd = &lp->rd_ring[lp->rx_next_done];
442 		writel(~DMA_STAT_DONE, &lp->rx_dma_regs->dmas);
443 	}
444 
445 	dmas = readl(&lp->rx_dma_regs->dmas);
446 
447 	if (dmas & DMA_STAT_HALT) {
448 		writel(~(DMA_STAT_HALT | DMA_STAT_ERR),
449 				&lp->rx_dma_regs->dmas);
450 
451 		lp->dma_halt_cnt++;
452 		rd->devcs = 0;
453 		skb = lp->rx_skb[lp->rx_next_done];
454 		rd->ca = CPHYSADDR(skb->data);
455 		dma_cache_wback((u32)rd, sizeof(*rd));
456 		korina_chain_rx(lp, rd);
457 	}
458 
459 	return count;
460 }
461 
462 static int korina_poll(struct napi_struct *napi, int budget)
463 {
464 	struct korina_private *lp =
465 		container_of(napi, struct korina_private, napi);
466 	struct net_device *dev = lp->dev;
467 	int work_done;
468 
469 	work_done = korina_rx(dev, budget);
470 	if (work_done < budget) {
471 		napi_complete_done(napi, work_done);
472 
473 		writel(readl(&lp->rx_dma_regs->dmasm) &
474 			~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
475 			&lp->rx_dma_regs->dmasm);
476 	}
477 	return work_done;
478 }
479 
480 /*
481  * Set or clear the multicast filter for this adaptor.
482  */
483 static void korina_multicast_list(struct net_device *dev)
484 {
485 	struct korina_private *lp = netdev_priv(dev);
486 	unsigned long flags;
487 	struct netdev_hw_addr *ha;
488 	u32 recognise = ETH_ARC_AB;	/* always accept broadcasts */
489 
490 	/* Set promiscuous mode */
491 	if (dev->flags & IFF_PROMISC)
492 		recognise |= ETH_ARC_PRO;
493 
494 	else if ((dev->flags & IFF_ALLMULTI) || (netdev_mc_count(dev) > 4))
495 		/* All multicast and broadcast */
496 		recognise |= ETH_ARC_AM;
497 
498 	/* Build the hash table */
499 	if (netdev_mc_count(dev) > 4) {
500 		u16 hash_table[4] = { 0 };
501 		u32 crc;
502 
503 		netdev_for_each_mc_addr(ha, dev) {
504 			crc = ether_crc_le(6, ha->addr);
505 			crc >>= 26;
506 			hash_table[crc >> 4] |= 1 << (15 - (crc & 0xf));
507 		}
508 		/* Accept filtered multicast */
509 		recognise |= ETH_ARC_AFM;
510 
511 		/* Fill the MAC hash tables with their values */
512 		writel((u32)(hash_table[1] << 16 | hash_table[0]),
513 					&lp->eth_regs->ethhash0);
514 		writel((u32)(hash_table[3] << 16 | hash_table[2]),
515 					&lp->eth_regs->ethhash1);
516 	}
517 
518 	spin_lock_irqsave(&lp->lock, flags);
519 	writel(recognise, &lp->eth_regs->etharc);
520 	spin_unlock_irqrestore(&lp->lock, flags);
521 }
522 
523 static void korina_tx(struct net_device *dev)
524 {
525 	struct korina_private *lp = netdev_priv(dev);
526 	struct dma_desc *td = &lp->td_ring[lp->tx_next_done];
527 	u32 devcs;
528 	u32 dmas;
529 
530 	spin_lock(&lp->lock);
531 
532 	/* Process all desc that are done */
533 	while (IS_DMA_FINISHED(td->control)) {
534 		if (lp->tx_full == 1) {
535 			netif_wake_queue(dev);
536 			lp->tx_full = 0;
537 		}
538 
539 		devcs = lp->td_ring[lp->tx_next_done].devcs;
540 		if ((devcs & (ETH_TX_FD | ETH_TX_LD)) !=
541 				(ETH_TX_FD | ETH_TX_LD)) {
542 			dev->stats.tx_errors++;
543 			dev->stats.tx_dropped++;
544 
545 			/* Should never happen */
546 			printk(KERN_ERR "%s: split tx ignored\n",
547 							dev->name);
548 		} else if (devcs & ETH_TX_TOK) {
549 			dev->stats.tx_packets++;
550 			dev->stats.tx_bytes +=
551 					lp->tx_skb[lp->tx_next_done]->len;
552 		} else {
553 			dev->stats.tx_errors++;
554 			dev->stats.tx_dropped++;
555 
556 			/* Underflow */
557 			if (devcs & ETH_TX_UND)
558 				dev->stats.tx_fifo_errors++;
559 
560 			/* Oversized frame */
561 			if (devcs & ETH_TX_OF)
562 				dev->stats.tx_aborted_errors++;
563 
564 			/* Excessive deferrals */
565 			if (devcs & ETH_TX_ED)
566 				dev->stats.tx_carrier_errors++;
567 
568 			/* Collisions: medium busy */
569 			if (devcs & ETH_TX_EC)
570 				dev->stats.collisions++;
571 
572 			/* Late collision */
573 			if (devcs & ETH_TX_LC)
574 				dev->stats.tx_window_errors++;
575 		}
576 
577 		/* We must always free the original skb */
578 		if (lp->tx_skb[lp->tx_next_done]) {
579 			dev_kfree_skb_any(lp->tx_skb[lp->tx_next_done]);
580 			lp->tx_skb[lp->tx_next_done] = NULL;
581 		}
582 
583 		lp->td_ring[lp->tx_next_done].control = DMA_DESC_IOF;
584 		lp->td_ring[lp->tx_next_done].devcs = ETH_TX_FD | ETH_TX_LD;
585 		lp->td_ring[lp->tx_next_done].link = 0;
586 		lp->td_ring[lp->tx_next_done].ca = 0;
587 		lp->tx_count--;
588 
589 		/* Go on to next transmission */
590 		lp->tx_next_done = (lp->tx_next_done + 1) & KORINA_TDS_MASK;
591 		td = &lp->td_ring[lp->tx_next_done];
592 
593 	}
594 
595 	/* Clear the DMA status register */
596 	dmas = readl(&lp->tx_dma_regs->dmas);
597 	writel(~dmas, &lp->tx_dma_regs->dmas);
598 
599 	writel(readl(&lp->tx_dma_regs->dmasm) &
600 			~(DMA_STAT_FINI | DMA_STAT_ERR),
601 			&lp->tx_dma_regs->dmasm);
602 
603 	spin_unlock(&lp->lock);
604 }
605 
606 static irqreturn_t
607 korina_tx_dma_interrupt(int irq, void *dev_id)
608 {
609 	struct net_device *dev = dev_id;
610 	struct korina_private *lp = netdev_priv(dev);
611 	u32 dmas, dmasm;
612 	irqreturn_t retval;
613 
614 	dmas = readl(&lp->tx_dma_regs->dmas);
615 
616 	if (dmas & (DMA_STAT_FINI | DMA_STAT_ERR)) {
617 		dmasm = readl(&lp->tx_dma_regs->dmasm);
618 		writel(dmasm | (DMA_STAT_FINI | DMA_STAT_ERR),
619 				&lp->tx_dma_regs->dmasm);
620 
621 		korina_tx(dev);
622 
623 		if (lp->tx_chain_status == desc_filled &&
624 			(readl(&(lp->tx_dma_regs->dmandptr)) == 0)) {
625 			writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
626 				&(lp->tx_dma_regs->dmandptr));
627 			lp->tx_chain_status = desc_empty;
628 			lp->tx_chain_head = lp->tx_chain_tail;
629 			netif_trans_update(dev);
630 		}
631 		if (dmas & DMA_STAT_ERR)
632 			printk(KERN_ERR "%s: DMA error\n", dev->name);
633 
634 		retval = IRQ_HANDLED;
635 	} else
636 		retval = IRQ_NONE;
637 
638 	return retval;
639 }
640 
641 
642 static void korina_check_media(struct net_device *dev, unsigned int init_media)
643 {
644 	struct korina_private *lp = netdev_priv(dev);
645 
646 	mii_check_media(&lp->mii_if, 0, init_media);
647 
648 	if (lp->mii_if.full_duplex)
649 		writel(readl(&lp->eth_regs->ethmac2) | ETH_MAC2_FD,
650 						&lp->eth_regs->ethmac2);
651 	else
652 		writel(readl(&lp->eth_regs->ethmac2) & ~ETH_MAC2_FD,
653 						&lp->eth_regs->ethmac2);
654 }
655 
656 static void korina_poll_media(struct timer_list *t)
657 {
658 	struct korina_private *lp = from_timer(lp, t, media_check_timer);
659 	struct net_device *dev = lp->dev;
660 
661 	korina_check_media(dev, 0);
662 	mod_timer(&lp->media_check_timer, jiffies + HZ);
663 }
664 
665 static void korina_set_carrier(struct mii_if_info *mii)
666 {
667 	if (mii->force_media) {
668 		/* autoneg is off: Link is always assumed to be up */
669 		if (!netif_carrier_ok(mii->dev))
670 			netif_carrier_on(mii->dev);
671 	} else  /* Let MMI library update carrier status */
672 		korina_check_media(mii->dev, 0);
673 }
674 
675 static int korina_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
676 {
677 	struct korina_private *lp = netdev_priv(dev);
678 	struct mii_ioctl_data *data = if_mii(rq);
679 	int rc;
680 
681 	if (!netif_running(dev))
682 		return -EINVAL;
683 	spin_lock_irq(&lp->lock);
684 	rc = generic_mii_ioctl(&lp->mii_if, data, cmd, NULL);
685 	spin_unlock_irq(&lp->lock);
686 	korina_set_carrier(&lp->mii_if);
687 
688 	return rc;
689 }
690 
691 /* ethtool helpers */
692 static void netdev_get_drvinfo(struct net_device *dev,
693 				struct ethtool_drvinfo *info)
694 {
695 	struct korina_private *lp = netdev_priv(dev);
696 
697 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
698 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
699 	strlcpy(info->bus_info, lp->dev->name, sizeof(info->bus_info));
700 }
701 
702 static int netdev_get_link_ksettings(struct net_device *dev,
703 				     struct ethtool_link_ksettings *cmd)
704 {
705 	struct korina_private *lp = netdev_priv(dev);
706 
707 	spin_lock_irq(&lp->lock);
708 	mii_ethtool_get_link_ksettings(&lp->mii_if, cmd);
709 	spin_unlock_irq(&lp->lock);
710 
711 	return 0;
712 }
713 
714 static int netdev_set_link_ksettings(struct net_device *dev,
715 				     const struct ethtool_link_ksettings *cmd)
716 {
717 	struct korina_private *lp = netdev_priv(dev);
718 	int rc;
719 
720 	spin_lock_irq(&lp->lock);
721 	rc = mii_ethtool_set_link_ksettings(&lp->mii_if, cmd);
722 	spin_unlock_irq(&lp->lock);
723 	korina_set_carrier(&lp->mii_if);
724 
725 	return rc;
726 }
727 
728 static u32 netdev_get_link(struct net_device *dev)
729 {
730 	struct korina_private *lp = netdev_priv(dev);
731 
732 	return mii_link_ok(&lp->mii_if);
733 }
734 
735 static const struct ethtool_ops netdev_ethtool_ops = {
736 	.get_drvinfo		= netdev_get_drvinfo,
737 	.get_link		= netdev_get_link,
738 	.get_link_ksettings	= netdev_get_link_ksettings,
739 	.set_link_ksettings	= netdev_set_link_ksettings,
740 };
741 
742 static int korina_alloc_ring(struct net_device *dev)
743 {
744 	struct korina_private *lp = netdev_priv(dev);
745 	struct sk_buff *skb;
746 	int i;
747 
748 	/* Initialize the transmit descriptors */
749 	for (i = 0; i < KORINA_NUM_TDS; i++) {
750 		lp->td_ring[i].control = DMA_DESC_IOF;
751 		lp->td_ring[i].devcs = ETH_TX_FD | ETH_TX_LD;
752 		lp->td_ring[i].ca = 0;
753 		lp->td_ring[i].link = 0;
754 	}
755 	lp->tx_next_done = lp->tx_chain_head = lp->tx_chain_tail =
756 			lp->tx_full = lp->tx_count = 0;
757 	lp->tx_chain_status = desc_empty;
758 
759 	/* Initialize the receive descriptors */
760 	for (i = 0; i < KORINA_NUM_RDS; i++) {
761 		skb = netdev_alloc_skb_ip_align(dev, KORINA_RBSIZE);
762 		if (!skb)
763 			return -ENOMEM;
764 		lp->rx_skb[i] = skb;
765 		lp->rd_ring[i].control = DMA_DESC_IOD |
766 				DMA_COUNT(KORINA_RBSIZE);
767 		lp->rd_ring[i].devcs = 0;
768 		lp->rd_ring[i].ca = CPHYSADDR(skb->data);
769 		lp->rd_ring[i].link = CPHYSADDR(&lp->rd_ring[i+1]);
770 	}
771 
772 	/* loop back receive descriptors, so the last
773 	 * descriptor points to the first one */
774 	lp->rd_ring[i - 1].link = CPHYSADDR(&lp->rd_ring[0]);
775 	lp->rd_ring[i - 1].control |= DMA_DESC_COD;
776 
777 	lp->rx_next_done  = 0;
778 	lp->rx_chain_head = 0;
779 	lp->rx_chain_tail = 0;
780 	lp->rx_chain_status = desc_empty;
781 
782 	return 0;
783 }
784 
785 static void korina_free_ring(struct net_device *dev)
786 {
787 	struct korina_private *lp = netdev_priv(dev);
788 	int i;
789 
790 	for (i = 0; i < KORINA_NUM_RDS; i++) {
791 		lp->rd_ring[i].control = 0;
792 		if (lp->rx_skb[i])
793 			dev_kfree_skb_any(lp->rx_skb[i]);
794 		lp->rx_skb[i] = NULL;
795 	}
796 
797 	for (i = 0; i < KORINA_NUM_TDS; i++) {
798 		lp->td_ring[i].control = 0;
799 		if (lp->tx_skb[i])
800 			dev_kfree_skb_any(lp->tx_skb[i]);
801 		lp->tx_skb[i] = NULL;
802 	}
803 }
804 
805 /*
806  * Initialize the RC32434 ethernet controller.
807  */
808 static int korina_init(struct net_device *dev)
809 {
810 	struct korina_private *lp = netdev_priv(dev);
811 
812 	/* Disable DMA */
813 	korina_abort_tx(dev);
814 	korina_abort_rx(dev);
815 
816 	/* reset ethernet logic */
817 	writel(0, &lp->eth_regs->ethintfc);
818 	while ((readl(&lp->eth_regs->ethintfc) & ETH_INT_FC_RIP))
819 		netif_trans_update(dev);
820 
821 	/* Enable Ethernet Interface */
822 	writel(ETH_INT_FC_EN, &lp->eth_regs->ethintfc);
823 
824 	/* Allocate rings */
825 	if (korina_alloc_ring(dev)) {
826 		printk(KERN_ERR "%s: descriptor allocation failed\n", dev->name);
827 		korina_free_ring(dev);
828 		return -ENOMEM;
829 	}
830 
831 	writel(0, &lp->rx_dma_regs->dmas);
832 	/* Start Rx DMA */
833 	korina_start_rx(lp, &lp->rd_ring[0]);
834 
835 	writel(readl(&lp->tx_dma_regs->dmasm) &
836 			~(DMA_STAT_FINI | DMA_STAT_ERR),
837 			&lp->tx_dma_regs->dmasm);
838 	writel(readl(&lp->rx_dma_regs->dmasm) &
839 			~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
840 			&lp->rx_dma_regs->dmasm);
841 
842 	/* Accept only packets destined for this Ethernet device address */
843 	writel(ETH_ARC_AB, &lp->eth_regs->etharc);
844 
845 	/* Set all Ether station address registers to their initial values */
846 	writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal0);
847 	writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah0);
848 
849 	writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal1);
850 	writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah1);
851 
852 	writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal2);
853 	writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah2);
854 
855 	writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal3);
856 	writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah3);
857 
858 
859 	/* Frame Length Checking, Pad Enable, CRC Enable, Full Duplex set */
860 	writel(ETH_MAC2_PE | ETH_MAC2_CEN | ETH_MAC2_FD,
861 			&lp->eth_regs->ethmac2);
862 
863 	/* Back to back inter-packet-gap */
864 	writel(0x15, &lp->eth_regs->ethipgt);
865 	/* Non - Back to back inter-packet-gap */
866 	writel(0x12, &lp->eth_regs->ethipgr);
867 
868 	/* Management Clock Prescaler Divisor
869 	 * Clock independent setting */
870 	writel(((idt_cpu_freq) / MII_CLOCK + 1) & ~1,
871 			&lp->eth_regs->ethmcp);
872 
873 	/* don't transmit until fifo contains 48b */
874 	writel(48, &lp->eth_regs->ethfifott);
875 
876 	writel(ETH_MAC1_RE, &lp->eth_regs->ethmac1);
877 
878 	napi_enable(&lp->napi);
879 	netif_start_queue(dev);
880 
881 	return 0;
882 }
883 
884 /*
885  * Restart the RC32434 ethernet controller.
886  */
887 static void korina_restart_task(struct work_struct *work)
888 {
889 	struct korina_private *lp = container_of(work,
890 			struct korina_private, restart_task);
891 	struct net_device *dev = lp->dev;
892 
893 	/*
894 	 * Disable interrupts
895 	 */
896 	disable_irq(lp->rx_irq);
897 	disable_irq(lp->tx_irq);
898 
899 	writel(readl(&lp->tx_dma_regs->dmasm) |
900 				DMA_STAT_FINI | DMA_STAT_ERR,
901 				&lp->tx_dma_regs->dmasm);
902 	writel(readl(&lp->rx_dma_regs->dmasm) |
903 				DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR,
904 				&lp->rx_dma_regs->dmasm);
905 
906 	napi_disable(&lp->napi);
907 
908 	korina_free_ring(dev);
909 
910 	if (korina_init(dev) < 0) {
911 		printk(KERN_ERR "%s: cannot restart device\n", dev->name);
912 		return;
913 	}
914 	korina_multicast_list(dev);
915 
916 	enable_irq(lp->tx_irq);
917 	enable_irq(lp->rx_irq);
918 }
919 
920 static void korina_tx_timeout(struct net_device *dev, unsigned int txqueue)
921 {
922 	struct korina_private *lp = netdev_priv(dev);
923 
924 	schedule_work(&lp->restart_task);
925 }
926 
927 #ifdef CONFIG_NET_POLL_CONTROLLER
928 static void korina_poll_controller(struct net_device *dev)
929 {
930 	disable_irq(dev->irq);
931 	korina_tx_dma_interrupt(dev->irq, dev);
932 	enable_irq(dev->irq);
933 }
934 #endif
935 
936 static int korina_open(struct net_device *dev)
937 {
938 	struct korina_private *lp = netdev_priv(dev);
939 	int ret;
940 
941 	/* Initialize */
942 	ret = korina_init(dev);
943 	if (ret < 0) {
944 		printk(KERN_ERR "%s: cannot open device\n", dev->name);
945 		goto out;
946 	}
947 
948 	/* Install the interrupt handler
949 	 * that handles the Done Finished */
950 	ret = request_irq(lp->rx_irq, korina_rx_dma_interrupt,
951 			0, "Korina ethernet Rx", dev);
952 	if (ret < 0) {
953 		printk(KERN_ERR "%s: unable to get Rx DMA IRQ %d\n",
954 			dev->name, lp->rx_irq);
955 		goto err_release;
956 	}
957 	ret = request_irq(lp->tx_irq, korina_tx_dma_interrupt,
958 			0, "Korina ethernet Tx", dev);
959 	if (ret < 0) {
960 		printk(KERN_ERR "%s: unable to get Tx DMA IRQ %d\n",
961 			dev->name, lp->tx_irq);
962 		goto err_free_rx_irq;
963 	}
964 
965 	mod_timer(&lp->media_check_timer, jiffies + 1);
966 out:
967 	return ret;
968 
969 err_free_rx_irq:
970 	free_irq(lp->rx_irq, dev);
971 err_release:
972 	korina_free_ring(dev);
973 	goto out;
974 }
975 
976 static int korina_close(struct net_device *dev)
977 {
978 	struct korina_private *lp = netdev_priv(dev);
979 	u32 tmp;
980 
981 	del_timer(&lp->media_check_timer);
982 
983 	/* Disable interrupts */
984 	disable_irq(lp->rx_irq);
985 	disable_irq(lp->tx_irq);
986 
987 	korina_abort_tx(dev);
988 	tmp = readl(&lp->tx_dma_regs->dmasm);
989 	tmp = tmp | DMA_STAT_FINI | DMA_STAT_ERR;
990 	writel(tmp, &lp->tx_dma_regs->dmasm);
991 
992 	korina_abort_rx(dev);
993 	tmp = readl(&lp->rx_dma_regs->dmasm);
994 	tmp = tmp | DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR;
995 	writel(tmp, &lp->rx_dma_regs->dmasm);
996 
997 	napi_disable(&lp->napi);
998 
999 	cancel_work_sync(&lp->restart_task);
1000 
1001 	korina_free_ring(dev);
1002 
1003 	free_irq(lp->rx_irq, dev);
1004 	free_irq(lp->tx_irq, dev);
1005 
1006 	return 0;
1007 }
1008 
1009 static const struct net_device_ops korina_netdev_ops = {
1010 	.ndo_open		= korina_open,
1011 	.ndo_stop		= korina_close,
1012 	.ndo_start_xmit		= korina_send_packet,
1013 	.ndo_set_rx_mode	= korina_multicast_list,
1014 	.ndo_tx_timeout		= korina_tx_timeout,
1015 	.ndo_do_ioctl		= korina_ioctl,
1016 	.ndo_validate_addr	= eth_validate_addr,
1017 	.ndo_set_mac_address	= eth_mac_addr,
1018 #ifdef CONFIG_NET_POLL_CONTROLLER
1019 	.ndo_poll_controller	= korina_poll_controller,
1020 #endif
1021 };
1022 
1023 static int korina_probe(struct platform_device *pdev)
1024 {
1025 	struct korina_device *bif = platform_get_drvdata(pdev);
1026 	struct korina_private *lp;
1027 	struct net_device *dev;
1028 	struct resource *r;
1029 	int rc;
1030 
1031 	dev = alloc_etherdev(sizeof(struct korina_private));
1032 	if (!dev)
1033 		return -ENOMEM;
1034 
1035 	SET_NETDEV_DEV(dev, &pdev->dev);
1036 	lp = netdev_priv(dev);
1037 
1038 	bif->dev = dev;
1039 	memcpy(dev->dev_addr, bif->mac, ETH_ALEN);
1040 
1041 	lp->rx_irq = platform_get_irq_byname(pdev, "korina_rx");
1042 	lp->tx_irq = platform_get_irq_byname(pdev, "korina_tx");
1043 
1044 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_regs");
1045 	dev->base_addr = r->start;
1046 	lp->eth_regs = ioremap(r->start, resource_size(r));
1047 	if (!lp->eth_regs) {
1048 		printk(KERN_ERR DRV_NAME ": cannot remap registers\n");
1049 		rc = -ENXIO;
1050 		goto probe_err_out;
1051 	}
1052 
1053 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_rx");
1054 	lp->rx_dma_regs = ioremap(r->start, resource_size(r));
1055 	if (!lp->rx_dma_regs) {
1056 		printk(KERN_ERR DRV_NAME ": cannot remap Rx DMA registers\n");
1057 		rc = -ENXIO;
1058 		goto probe_err_dma_rx;
1059 	}
1060 
1061 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_tx");
1062 	lp->tx_dma_regs = ioremap(r->start, resource_size(r));
1063 	if (!lp->tx_dma_regs) {
1064 		printk(KERN_ERR DRV_NAME ": cannot remap Tx DMA registers\n");
1065 		rc = -ENXIO;
1066 		goto probe_err_dma_tx;
1067 	}
1068 
1069 	lp->td_ring = kmalloc(TD_RING_SIZE + RD_RING_SIZE, GFP_KERNEL);
1070 	if (!lp->td_ring) {
1071 		rc = -ENXIO;
1072 		goto probe_err_td_ring;
1073 	}
1074 
1075 	dma_cache_inv((unsigned long)(lp->td_ring),
1076 			TD_RING_SIZE + RD_RING_SIZE);
1077 
1078 	/* now convert TD_RING pointer to KSEG1 */
1079 	lp->td_ring = (struct dma_desc *)KSEG1ADDR(lp->td_ring);
1080 	lp->rd_ring = &lp->td_ring[KORINA_NUM_TDS];
1081 
1082 	spin_lock_init(&lp->lock);
1083 	/* just use the rx dma irq */
1084 	dev->irq = lp->rx_irq;
1085 	lp->dev = dev;
1086 
1087 	dev->netdev_ops = &korina_netdev_ops;
1088 	dev->ethtool_ops = &netdev_ethtool_ops;
1089 	dev->watchdog_timeo = TX_TIMEOUT;
1090 	netif_napi_add(dev, &lp->napi, korina_poll, NAPI_POLL_WEIGHT);
1091 
1092 	lp->phy_addr = (((lp->rx_irq == 0x2c? 1:0) << 8) | 0x05);
1093 	lp->mii_if.dev = dev;
1094 	lp->mii_if.mdio_read = mdio_read;
1095 	lp->mii_if.mdio_write = mdio_write;
1096 	lp->mii_if.phy_id = lp->phy_addr;
1097 	lp->mii_if.phy_id_mask = 0x1f;
1098 	lp->mii_if.reg_num_mask = 0x1f;
1099 
1100 	rc = register_netdev(dev);
1101 	if (rc < 0) {
1102 		printk(KERN_ERR DRV_NAME
1103 			": cannot register net device: %d\n", rc);
1104 		goto probe_err_register;
1105 	}
1106 	timer_setup(&lp->media_check_timer, korina_poll_media, 0);
1107 
1108 	INIT_WORK(&lp->restart_task, korina_restart_task);
1109 
1110 	printk(KERN_INFO "%s: " DRV_NAME "-" DRV_VERSION " " DRV_RELDATE "\n",
1111 			dev->name);
1112 out:
1113 	return rc;
1114 
1115 probe_err_register:
1116 	kfree((struct dma_desc *)KSEG0ADDR(lp->td_ring));
1117 probe_err_td_ring:
1118 	iounmap(lp->tx_dma_regs);
1119 probe_err_dma_tx:
1120 	iounmap(lp->rx_dma_regs);
1121 probe_err_dma_rx:
1122 	iounmap(lp->eth_regs);
1123 probe_err_out:
1124 	free_netdev(dev);
1125 	goto out;
1126 }
1127 
1128 static int korina_remove(struct platform_device *pdev)
1129 {
1130 	struct korina_device *bif = platform_get_drvdata(pdev);
1131 	struct korina_private *lp = netdev_priv(bif->dev);
1132 
1133 	iounmap(lp->eth_regs);
1134 	iounmap(lp->rx_dma_regs);
1135 	iounmap(lp->tx_dma_regs);
1136 	kfree((struct dma_desc *)KSEG0ADDR(lp->td_ring));
1137 
1138 	unregister_netdev(bif->dev);
1139 	free_netdev(bif->dev);
1140 
1141 	return 0;
1142 }
1143 
1144 static struct platform_driver korina_driver = {
1145 	.driver.name = "korina",
1146 	.probe = korina_probe,
1147 	.remove = korina_remove,
1148 };
1149 
1150 module_platform_driver(korina_driver);
1151 
1152 MODULE_AUTHOR("Philip Rischel <rischelp@idt.com>");
1153 MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
1154 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
1155 MODULE_AUTHOR("Roman Yeryomin <roman@advem.lv>");
1156 MODULE_DESCRIPTION("IDT RC32434 (Korina) Ethernet driver");
1157 MODULE_LICENSE("GPL");
1158