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Merge branch 'for-linus' of git://git.infradead.org/users/sameo/mfd-2.6
[linux-btrfs-devel.git] / drivers / net / korina.c
blob763844c587fd13ac9303347e0408855598a1bbe6
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 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 *
13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
14 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
15 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
16 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
19 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 *
24 * You should have received a copy of the GNU General Public License along
25 * with this program; if not, write to the Free Software Foundation, Inc.,
26 * 675 Mass Ave, Cambridge, MA 02139, USA.
27 *
28 * Writing to a DMA status register:
29 *
30 * When writing to the status register, you should mask the bit you have
31 * been testing the status register with. Both Tx and Rx DMA registers
32 * should stick to this procedure.
33 */
34
35 #include <linux/module.h>
36 #include <linux/kernel.h>
37 #include <linux/moduleparam.h>
38 #include <linux/sched.h>
39 #include <linux/ctype.h>
40 #include <linux/types.h>
41 #include <linux/interrupt.h>
42 #include <linux/init.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
57 #include <asm/bootinfo.h>
58 #include <asm/system.h>
59 #include <asm/bitops.h>
60 #include <asm/pgtable.h>
61 #include <asm/segment.h>
62 #include <asm/io.h>
63 #include <asm/dma.h>
64
65 #include <asm/mach-rc32434/rb.h>
66 #include <asm/mach-rc32434/rc32434.h>
67 #include <asm/mach-rc32434/eth.h>
68 #include <asm/mach-rc32434/dma_v.h>
69
70 #define DRV_NAME "korina"
71 #define DRV_VERSION "0.10"
72 #define DRV_RELDATE "04Mar2008"
73
74 #define STATION_ADDRESS_HIGH(dev) (((dev)->dev_addr[0] << 8) | \
75 ((dev)->dev_addr[1]))
76 #define STATION_ADDRESS_LOW(dev) (((dev)->dev_addr[2] << 24) | \
77 ((dev)->dev_addr[3] << 16) | \
78 ((dev)->dev_addr[4] << 8) | \
79 ((dev)->dev_addr[5]))
80
81 #define MII_CLOCK 1250000 /* no more than 2.5MHz */
82
83 /* the following must be powers of two */
84 #define KORINA_NUM_RDS 64 /* number of receive descriptors */
85 #define KORINA_NUM_TDS 64 /* number of transmit descriptors */
86
87 /* KORINA_RBSIZE is the hardware's default maximum receive
88 * frame size in bytes. Having this hardcoded means that there
89 * is no support for MTU sizes greater than 1500. */
90 #define KORINA_RBSIZE 1536 /* size of one resource buffer = Ether MTU */
91 #define KORINA_RDS_MASK (KORINA_NUM_RDS - 1)
92 #define KORINA_TDS_MASK (KORINA_NUM_TDS - 1)
93 #define RD_RING_SIZE (KORINA_NUM_RDS * sizeof(struct dma_desc))
94 #define TD_RING_SIZE (KORINA_NUM_TDS * sizeof(struct dma_desc))
95
96 #define TX_TIMEOUT (6000 * HZ / 1000)
97
98 enum chain_status { desc_filled, desc_empty };
99 #define IS_DMA_FINISHED(X) (((X) & (DMA_DESC_FINI)) != 0)
100 #define IS_DMA_DONE(X) (((X) & (DMA_DESC_DONE)) != 0)
101 #define RCVPKT_LENGTH(X) (((X) & ETH_RX_LEN) >> ETH_RX_LEN_BIT)
102
103 /* Information that need to be kept for each board. */
104 struct korina_private {
105 struct eth_regs *eth_regs;
106 struct dma_reg *rx_dma_regs;
107 struct dma_reg *tx_dma_regs;
108 struct dma_desc *td_ring; /* transmit descriptor ring */
109 struct dma_desc *rd_ring; /* receive descriptor ring */
110
111 struct sk_buff *tx_skb[KORINA_NUM_TDS];
112 struct sk_buff *rx_skb[KORINA_NUM_RDS];
113
114 int rx_next_done;
115 int rx_chain_head;
116 int rx_chain_tail;
117 enum chain_status rx_chain_status;
118
119 int tx_next_done;
120 int tx_chain_head;
121 int tx_chain_tail;
122 enum chain_status tx_chain_status;
123 int tx_count;
124 int tx_full;
125
126 int rx_irq;
127 int tx_irq;
128 int ovr_irq;
129 int und_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 dev->trans_start = jiffies;
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_BUSY;
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 dev->trans_start = jiffies;
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 /* Update statistics counters */
372 if (devcs & ETH_RX_CRC)
373 dev->stats.rx_crc_errors++;
374 if (devcs & ETH_RX_LOR)
375 dev->stats.rx_length_errors++;
376 if (devcs & ETH_RX_LE)
377 dev->stats.rx_length_errors++;
378 if (devcs & ETH_RX_OVR)
379 dev->stats.rx_fifo_errors++;
380 if (devcs & ETH_RX_CV)
381 dev->stats.rx_frame_errors++;
382 if (devcs & ETH_RX_CES)
383 dev->stats.rx_length_errors++;
384 if (devcs & ETH_RX_MP)
385 dev->stats.multicast++;
386
387 if ((devcs & ETH_RX_LD) != ETH_RX_LD) {
388 /* check that this is a whole packet
389 * WARNING: DMA_FD bit incorrectly set
390 * in Rc32434 (errata ref #077) */
391 dev->stats.rx_errors++;
392 dev->stats.rx_dropped++;
393 } else if ((devcs & ETH_RX_ROK)) {
394 pkt_len = RCVPKT_LENGTH(devcs);
395
396 /* must be the (first and) last
397 * descriptor then */
398 pkt_buf = (u8 *)lp->rx_skb[lp->rx_next_done]->data;
399
400 /* invalidate the cache */
401 dma_cache_inv((unsigned long)pkt_buf, pkt_len - 4);
402
403 /* Malloc up new buffer. */
404 skb_new = netdev_alloc_skb_ip_align(dev, KORINA_RBSIZE);
405
406 if (!skb_new)
407 break;
408 /* Do not count the CRC */
409 skb_put(skb, pkt_len - 4);
410 skb->protocol = eth_type_trans(skb, dev);
411
412 /* Pass the packet to upper layers */
413 netif_receive_skb(skb);
414 dev->stats.rx_packets++;
415 dev->stats.rx_bytes += pkt_len;
416
417 /* Update the mcast stats */
418 if (devcs & ETH_RX_MP)
419 dev->stats.multicast++;
420
421 lp->rx_skb[lp->rx_next_done] = skb_new;
422 }
423
424 rd->devcs = 0;
425
426 /* Restore descriptor's curr_addr */
427 if (skb_new)
428 rd->ca = CPHYSADDR(skb_new->data);
429 else
430 rd->ca = CPHYSADDR(skb->data);
431
432 rd->control = DMA_COUNT(KORINA_RBSIZE) |
433 DMA_DESC_COD | DMA_DESC_IOD;
434 lp->rd_ring[(lp->rx_next_done - 1) &
435 KORINA_RDS_MASK].control &=
436 ~DMA_DESC_COD;
437
438 lp->rx_next_done = (lp->rx_next_done + 1) & KORINA_RDS_MASK;
439 dma_cache_wback((u32)rd, sizeof(*rd));
440 rd = &lp->rd_ring[lp->rx_next_done];
441 writel(~DMA_STAT_DONE, &lp->rx_dma_regs->dmas);
442 }
443
444 dmas = readl(&lp->rx_dma_regs->dmas);
445
446 if (dmas & DMA_STAT_HALT) {
447 writel(~(DMA_STAT_HALT | DMA_STAT_ERR),
448 &lp->rx_dma_regs->dmas);
449
450 lp->dma_halt_cnt++;
451 rd->devcs = 0;
452 skb = lp->rx_skb[lp->rx_next_done];
453 rd->ca = CPHYSADDR(skb->data);
454 dma_cache_wback((u32)rd, sizeof(*rd));
455 korina_chain_rx(lp, rd);
456 }
457
458 return count;
459 }
460
461 static int korina_poll(struct napi_struct *napi, int budget)
462 {
463 struct korina_private *lp =
464 container_of(napi, struct korina_private, napi);
465 struct net_device *dev = lp->dev;
466 int work_done;
467
468 work_done = korina_rx(dev, budget);
469 if (work_done < budget) {
470 napi_complete(napi);
471
472 writel(readl(&lp->rx_dma_regs->dmasm) &
473 ~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
474 &lp->rx_dma_regs->dmasm);
475 }
476 return work_done;
477 }
478
479 /*
480 * Set or clear the multicast filter for this adaptor.
481 */
482 static void korina_multicast_list(struct net_device *dev)
483 {
484 struct korina_private *lp = netdev_priv(dev);
485 unsigned long flags;
486 struct netdev_hw_addr *ha;
487 u32 recognise = ETH_ARC_AB; /* always accept broadcasts */
488 int i;
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];
501 u32 crc;
502
503 for (i = 0; i < 4; i++)
504 hash_table[i] = 0;
505
506 netdev_for_each_mc_addr(ha, dev) {
507 crc = ether_crc_le(6, ha->addr);
508 crc >>= 26;
509 hash_table[crc >> 4] |= 1 << (15 - (crc & 0xf));
510 }
511 /* Accept filtered multicast */
512 recognise |= ETH_ARC_AFM;
513
514 /* Fill the MAC hash tables with their values */
515 writel((u32)(hash_table[1] << 16 | hash_table[0]),
516 &lp->eth_regs->ethhash0);
517 writel((u32)(hash_table[3] << 16 | hash_table[2]),
518 &lp->eth_regs->ethhash1);
519 }
520
521 spin_lock_irqsave(&lp->lock, flags);
522 writel(recognise, &lp->eth_regs->etharc);
523 spin_unlock_irqrestore(&lp->lock, flags);
524 }
525
526 static void korina_tx(struct net_device *dev)
527 {
528 struct korina_private *lp = netdev_priv(dev);
529 struct dma_desc *td = &lp->td_ring[lp->tx_next_done];
530 u32 devcs;
531 u32 dmas;
532
533 spin_lock(&lp->lock);
534
535 /* Process all desc that are done */
536 while (IS_DMA_FINISHED(td->control)) {
537 if (lp->tx_full == 1) {
538 netif_wake_queue(dev);
539 lp->tx_full = 0;
540 }
541
542 devcs = lp->td_ring[lp->tx_next_done].devcs;
543 if ((devcs & (ETH_TX_FD | ETH_TX_LD)) !=
544 (ETH_TX_FD | ETH_TX_LD)) {
545 dev->stats.tx_errors++;
546 dev->stats.tx_dropped++;
547
548 /* Should never happen */
549 printk(KERN_ERR "%s: split tx ignored\n",
550 dev->name);
551 } else if (devcs & ETH_TX_TOK) {
552 dev->stats.tx_packets++;
553 dev->stats.tx_bytes +=
554 lp->tx_skb[lp->tx_next_done]->len;
555 } else {
556 dev->stats.tx_errors++;
557 dev->stats.tx_dropped++;
558
559 /* Underflow */
560 if (devcs & ETH_TX_UND)
561 dev->stats.tx_fifo_errors++;
562
563 /* Oversized frame */
564 if (devcs & ETH_TX_OF)
565 dev->stats.tx_aborted_errors++;
566
567 /* Excessive deferrals */
568 if (devcs & ETH_TX_ED)
569 dev->stats.tx_carrier_errors++;
570
571 /* Collisions: medium busy */
572 if (devcs & ETH_TX_EC)
573 dev->stats.collisions++;
574
575 /* Late collision */
576 if (devcs & ETH_TX_LC)
577 dev->stats.tx_window_errors++;
578 }
579
580 /* We must always free the original skb */
581 if (lp->tx_skb[lp->tx_next_done]) {
582 dev_kfree_skb_any(lp->tx_skb[lp->tx_next_done]);
583 lp->tx_skb[lp->tx_next_done] = NULL;
584 }
585
586 lp->td_ring[lp->tx_next_done].control = DMA_DESC_IOF;
587 lp->td_ring[lp->tx_next_done].devcs = ETH_TX_FD | ETH_TX_LD;
588 lp->td_ring[lp->tx_next_done].link = 0;
589 lp->td_ring[lp->tx_next_done].ca = 0;
590 lp->tx_count--;
591
592 /* Go on to next transmission */
593 lp->tx_next_done = (lp->tx_next_done + 1) & KORINA_TDS_MASK;
594 td = &lp->td_ring[lp->tx_next_done];
595
596 }
597
598 /* Clear the DMA status register */
599 dmas = readl(&lp->tx_dma_regs->dmas);
600 writel(~dmas, &lp->tx_dma_regs->dmas);
601
602 writel(readl(&lp->tx_dma_regs->dmasm) &
603 ~(DMA_STAT_FINI | DMA_STAT_ERR),
604 &lp->tx_dma_regs->dmasm);
605
606 spin_unlock(&lp->lock);
607 }
608
609 static irqreturn_t
610 korina_tx_dma_interrupt(int irq, void *dev_id)
611 {
612 struct net_device *dev = dev_id;
613 struct korina_private *lp = netdev_priv(dev);
614 u32 dmas, dmasm;
615 irqreturn_t retval;
616
617 dmas = readl(&lp->tx_dma_regs->dmas);
618
619 if (dmas & (DMA_STAT_FINI | DMA_STAT_ERR)) {
620 dmasm = readl(&lp->tx_dma_regs->dmasm);
621 writel(dmasm | (DMA_STAT_FINI | DMA_STAT_ERR),
622 &lp->tx_dma_regs->dmasm);
623
624 korina_tx(dev);
625
626 if (lp->tx_chain_status == desc_filled &&
627 (readl(&(lp->tx_dma_regs->dmandptr)) == 0)) {
628 writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
629 &(lp->tx_dma_regs->dmandptr));
630 lp->tx_chain_status = desc_empty;
631 lp->tx_chain_head = lp->tx_chain_tail;
632 dev->trans_start = jiffies;
633 }
634 if (dmas & DMA_STAT_ERR)
635 printk(KERN_ERR "%s: DMA error\n", dev->name);
636
637 retval = IRQ_HANDLED;
638 } else
639 retval = IRQ_NONE;
640
641 return retval;
642 }
643
644
645 static void korina_check_media(struct net_device *dev, unsigned int init_media)
646 {
647 struct korina_private *lp = netdev_priv(dev);
648
649 mii_check_media(&lp->mii_if, 0, init_media);
650
651 if (lp->mii_if.full_duplex)
652 writel(readl(&lp->eth_regs->ethmac2) | ETH_MAC2_FD,
653 &lp->eth_regs->ethmac2);
654 else
655 writel(readl(&lp->eth_regs->ethmac2) & ~ETH_MAC2_FD,
656 &lp->eth_regs->ethmac2);
657 }
658
659 static void korina_poll_media(unsigned long data)
660 {
661 struct net_device *dev = (struct net_device *) data;
662 struct korina_private *lp = netdev_priv(dev);
663
664 korina_check_media(dev, 0);
665 mod_timer(&lp->media_check_timer, jiffies + HZ);
666 }
667
668 static void korina_set_carrier(struct mii_if_info *mii)
669 {
670 if (mii->force_media) {
671 /* autoneg is off: Link is always assumed to be up */
672 if (!netif_carrier_ok(mii->dev))
673 netif_carrier_on(mii->dev);
674 } else /* Let MMI library update carrier status */
675 korina_check_media(mii->dev, 0);
676 }
677
678 static int korina_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
679 {
680 struct korina_private *lp = netdev_priv(dev);
681 struct mii_ioctl_data *data = if_mii(rq);
682 int rc;
683
684 if (!netif_running(dev))
685 return -EINVAL;
686 spin_lock_irq(&lp->lock);
687 rc = generic_mii_ioctl(&lp->mii_if, data, cmd, NULL);
688 spin_unlock_irq(&lp->lock);
689 korina_set_carrier(&lp->mii_if);
690
691 return rc;
692 }
693
694 /* ethtool helpers */
695 static void netdev_get_drvinfo(struct net_device *dev,
696 struct ethtool_drvinfo *info)
697 {
698 struct korina_private *lp = netdev_priv(dev);
699
700 strcpy(info->driver, DRV_NAME);
701 strcpy(info->version, DRV_VERSION);
702 strcpy(info->bus_info, lp->dev->name);
703 }
704
705 static int netdev_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
706 {
707 struct korina_private *lp = netdev_priv(dev);
708 int rc;
709
710 spin_lock_irq(&lp->lock);
711 rc = mii_ethtool_gset(&lp->mii_if, cmd);
712 spin_unlock_irq(&lp->lock);
713
714 return rc;
715 }
716
717 static int netdev_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
718 {
719 struct korina_private *lp = netdev_priv(dev);
720 int rc;
721
722 spin_lock_irq(&lp->lock);
723 rc = mii_ethtool_sset(&lp->mii_if, cmd);
724 spin_unlock_irq(&lp->lock);
725 korina_set_carrier(&lp->mii_if);
726
727 return rc;
728 }
729
730 static u32 netdev_get_link(struct net_device *dev)
731 {
732 struct korina_private *lp = netdev_priv(dev);
733
734 return mii_link_ok(&lp->mii_if);
735 }
736
737 static const struct ethtool_ops netdev_ethtool_ops = {
738 .get_drvinfo = netdev_get_drvinfo,
739 .get_settings = netdev_get_settings,
740 .set_settings = netdev_set_settings,
741 .get_link = netdev_get_link,
742 };
743
744 static int korina_alloc_ring(struct net_device *dev)
745 {
746 struct korina_private *lp = netdev_priv(dev);
747 struct sk_buff *skb;
748 int i;
749
750 /* Initialize the transmit descriptors */
751 for (i = 0; i < KORINA_NUM_TDS; i++) {
752 lp->td_ring[i].control = DMA_DESC_IOF;
753 lp->td_ring[i].devcs = ETH_TX_FD | ETH_TX_LD;
754 lp->td_ring[i].ca = 0;
755 lp->td_ring[i].link = 0;
756 }
757 lp->tx_next_done = lp->tx_chain_head = lp->tx_chain_tail =
758 lp->tx_full = lp->tx_count = 0;
759 lp->tx_chain_status = desc_empty;
760
761 /* Initialize the receive descriptors */
762 for (i = 0; i < KORINA_NUM_RDS; i++) {
763 skb = netdev_alloc_skb_ip_align(dev, KORINA_RBSIZE);
764 if (!skb)
765 return -ENOMEM;
766 lp->rx_skb[i] = skb;
767 lp->rd_ring[i].control = DMA_DESC_IOD |
768 DMA_COUNT(KORINA_RBSIZE);
769 lp->rd_ring[i].devcs = 0;
770 lp->rd_ring[i].ca = CPHYSADDR(skb->data);
771 lp->rd_ring[i].link = CPHYSADDR(&lp->rd_ring[i+1]);
772 }
773
774 /* loop back receive descriptors, so the last
775 * descriptor points to the first one */
776 lp->rd_ring[i - 1].link = CPHYSADDR(&lp->rd_ring[0]);
777 lp->rd_ring[i - 1].control |= DMA_DESC_COD;
778
779 lp->rx_next_done = 0;
780 lp->rx_chain_head = 0;
781 lp->rx_chain_tail = 0;
782 lp->rx_chain_status = desc_empty;
783
784 return 0;
785 }
786
787 static void korina_free_ring(struct net_device *dev)
788 {
789 struct korina_private *lp = netdev_priv(dev);
790 int i;
791
792 for (i = 0; i < KORINA_NUM_RDS; i++) {
793 lp->rd_ring[i].control = 0;
794 if (lp->rx_skb[i])
795 dev_kfree_skb_any(lp->rx_skb[i]);
796 lp->rx_skb[i] = NULL;
797 }
798
799 for (i = 0; i < KORINA_NUM_TDS; i++) {
800 lp->td_ring[i].control = 0;
801 if (lp->tx_skb[i])
802 dev_kfree_skb_any(lp->tx_skb[i]);
803 lp->tx_skb[i] = NULL;
804 }
805 }
806
807 /*
808 * Initialize the RC32434 ethernet controller.
809 */
810 static int korina_init(struct net_device *dev)
811 {
812 struct korina_private *lp = netdev_priv(dev);
813
814 /* Disable DMA */
815 korina_abort_tx(dev);
816 korina_abort_rx(dev);
817
818 /* reset ethernet logic */
819 writel(0, &lp->eth_regs->ethintfc);
820 while ((readl(&lp->eth_regs->ethintfc) & ETH_INT_FC_RIP))
821 dev->trans_start = jiffies;
822
823 /* Enable Ethernet Interface */
824 writel(ETH_INT_FC_EN, &lp->eth_regs->ethintfc);
825
826 /* Allocate rings */
827 if (korina_alloc_ring(dev)) {
828 printk(KERN_ERR "%s: descriptor allocation failed\n", dev->name);
829 korina_free_ring(dev);
830 return -ENOMEM;
831 }
832
833 writel(0, &lp->rx_dma_regs->dmas);
834 /* Start Rx DMA */
835 korina_start_rx(lp, &lp->rd_ring[0]);
836
837 writel(readl(&lp->tx_dma_regs->dmasm) &
838 ~(DMA_STAT_FINI | DMA_STAT_ERR),
839 &lp->tx_dma_regs->dmasm);
840 writel(readl(&lp->rx_dma_regs->dmasm) &
841 ~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
842 &lp->rx_dma_regs->dmasm);
843
844 /* Accept only packets destined for this Ethernet device address */
845 writel(ETH_ARC_AB, &lp->eth_regs->etharc);
846
847 /* Set all Ether station address registers to their initial values */
848 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal0);
849 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah0);
850
851 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal1);
852 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah1);
853
854 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal2);
855 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah2);
856
857 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal3);
858 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah3);
859
860
861 /* Frame Length Checking, Pad Enable, CRC Enable, Full Duplex set */
862 writel(ETH_MAC2_PE | ETH_MAC2_CEN | ETH_MAC2_FD,
863 &lp->eth_regs->ethmac2);
864
865 /* Back to back inter-packet-gap */
866 writel(0x15, &lp->eth_regs->ethipgt);
867 /* Non - Back to back inter-packet-gap */
868 writel(0x12, &lp->eth_regs->ethipgr);
869
870 /* Management Clock Prescaler Divisor
871 * Clock independent setting */
872 writel(((idt_cpu_freq) / MII_CLOCK + 1) & ~1,
873 &lp->eth_regs->ethmcp);
874
875 /* don't transmit until fifo contains 48b */
876 writel(48, &lp->eth_regs->ethfifott);
877
878 writel(ETH_MAC1_RE, &lp->eth_regs->ethmac1);
879
880 napi_enable(&lp->napi);
881 netif_start_queue(dev);
882
883 return 0;
884 }
885
886 /*
887 * Restart the RC32434 ethernet controller.
888 */
889 static void korina_restart_task(struct work_struct *work)
890 {
891 struct korina_private *lp = container_of(work,
892 struct korina_private, restart_task);
893 struct net_device *dev = lp->dev;
894
895 /*
896 * Disable interrupts
897 */
898 disable_irq(lp->rx_irq);
899 disable_irq(lp->tx_irq);
900 disable_irq(lp->ovr_irq);
901 disable_irq(lp->und_irq);
902
903 writel(readl(&lp->tx_dma_regs->dmasm) |
904 DMA_STAT_FINI | DMA_STAT_ERR,
905 &lp->tx_dma_regs->dmasm);
906 writel(readl(&lp->rx_dma_regs->dmasm) |
907 DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR,
908 &lp->rx_dma_regs->dmasm);
909
910 korina_free_ring(dev);
911
912 napi_disable(&lp->napi);
913
914 if (korina_init(dev) < 0) {
915 printk(KERN_ERR "%s: cannot restart device\n", dev->name);
916 return;
917 }
918 korina_multicast_list(dev);
919
920 enable_irq(lp->und_irq);
921 enable_irq(lp->ovr_irq);
922 enable_irq(lp->tx_irq);
923 enable_irq(lp->rx_irq);
924 }
925
926 static void korina_clear_and_restart(struct net_device *dev, u32 value)
927 {
928 struct korina_private *lp = netdev_priv(dev);
929
930 netif_stop_queue(dev);
931 writel(value, &lp->eth_regs->ethintfc);
932 schedule_work(&lp->restart_task);
933 }
934
935 /* Ethernet Tx Underflow interrupt */
936 static irqreturn_t korina_und_interrupt(int irq, void *dev_id)
937 {
938 struct net_device *dev = dev_id;
939 struct korina_private *lp = netdev_priv(dev);
940 unsigned int und;
941
942 spin_lock(&lp->lock);
943
944 und = readl(&lp->eth_regs->ethintfc);
945
946 if (und & ETH_INT_FC_UND)
947 korina_clear_and_restart(dev, und & ~ETH_INT_FC_UND);
948
949 spin_unlock(&lp->lock);
950
951 return IRQ_HANDLED;
952 }
953
954 static void korina_tx_timeout(struct net_device *dev)
955 {
956 struct korina_private *lp = netdev_priv(dev);
957
958 schedule_work(&lp->restart_task);
959 }
960
961 /* Ethernet Rx Overflow interrupt */
962 static irqreturn_t
963 korina_ovr_interrupt(int irq, void *dev_id)
964 {
965 struct net_device *dev = dev_id;
966 struct korina_private *lp = netdev_priv(dev);
967 unsigned int ovr;
968
969 spin_lock(&lp->lock);
970 ovr = readl(&lp->eth_regs->ethintfc);
971
972 if (ovr & ETH_INT_FC_OVR)
973 korina_clear_and_restart(dev, ovr & ~ETH_INT_FC_OVR);
974
975 spin_unlock(&lp->lock);
976
977 return IRQ_HANDLED;
978 }
979
980 #ifdef CONFIG_NET_POLL_CONTROLLER
981 static void korina_poll_controller(struct net_device *dev)
982 {
983 disable_irq(dev->irq);
984 korina_tx_dma_interrupt(dev->irq, dev);
985 enable_irq(dev->irq);
986 }
987 #endif
988
989 static int korina_open(struct net_device *dev)
990 {
991 struct korina_private *lp = netdev_priv(dev);
992 int ret;
993
994 /* Initialize */
995 ret = korina_init(dev);
996 if (ret < 0) {
997 printk(KERN_ERR "%s: cannot open device\n", dev->name);
998 goto out;
999 }
1000
1001 /* Install the interrupt handler
1002 * that handles the Done Finished
1003 * Ovr and Und Events */
1004 ret = request_irq(lp->rx_irq, korina_rx_dma_interrupt,
1005 IRQF_DISABLED, "Korina ethernet Rx", dev);
1006 if (ret < 0) {
1007 printk(KERN_ERR "%s: unable to get Rx DMA IRQ %d\n",
1008 dev->name, lp->rx_irq);
1009 goto err_release;
1010 }
1011 ret = request_irq(lp->tx_irq, korina_tx_dma_interrupt,
1012 IRQF_DISABLED, "Korina ethernet Tx", dev);
1013 if (ret < 0) {
1014 printk(KERN_ERR "%s: unable to get Tx DMA IRQ %d\n",
1015 dev->name, lp->tx_irq);
1016 goto err_free_rx_irq;
1017 }
1018
1019 /* Install handler for overrun error. */
1020 ret = request_irq(lp->ovr_irq, korina_ovr_interrupt,
1021 IRQF_DISABLED, "Ethernet Overflow", dev);
1022 if (ret < 0) {
1023 printk(KERN_ERR "%s: unable to get OVR IRQ %d\n",
1024 dev->name, lp->ovr_irq);
1025 goto err_free_tx_irq;
1026 }
1027
1028 /* Install handler for underflow error. */
1029 ret = request_irq(lp->und_irq, korina_und_interrupt,
1030 IRQF_DISABLED, "Ethernet Underflow", dev);
1031 if (ret < 0) {
1032 printk(KERN_ERR "%s: unable to get UND IRQ %d\n",
1033 dev->name, lp->und_irq);
1034 goto err_free_ovr_irq;
1035 }
1036 mod_timer(&lp->media_check_timer, jiffies + 1);
1037 out:
1038 return ret;
1039
1040 err_free_ovr_irq:
1041 free_irq(lp->ovr_irq, dev);
1042 err_free_tx_irq:
1043 free_irq(lp->tx_irq, dev);
1044 err_free_rx_irq:
1045 free_irq(lp->rx_irq, dev);
1046 err_release:
1047 korina_free_ring(dev);
1048 goto out;
1049 }
1050
1051 static int korina_close(struct net_device *dev)
1052 {
1053 struct korina_private *lp = netdev_priv(dev);
1054 u32 tmp;
1055
1056 del_timer(&lp->media_check_timer);
1057
1058 /* Disable interrupts */
1059 disable_irq(lp->rx_irq);
1060 disable_irq(lp->tx_irq);
1061 disable_irq(lp->ovr_irq);
1062 disable_irq(lp->und_irq);
1063
1064 korina_abort_tx(dev);
1065 tmp = readl(&lp->tx_dma_regs->dmasm);
1066 tmp = tmp | DMA_STAT_FINI | DMA_STAT_ERR;
1067 writel(tmp, &lp->tx_dma_regs->dmasm);
1068
1069 korina_abort_rx(dev);
1070 tmp = readl(&lp->rx_dma_regs->dmasm);
1071 tmp = tmp | DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR;
1072 writel(tmp, &lp->rx_dma_regs->dmasm);
1073
1074 korina_free_ring(dev);
1075
1076 napi_disable(&lp->napi);
1077
1078 cancel_work_sync(&lp->restart_task);
1079
1080 free_irq(lp->rx_irq, dev);
1081 free_irq(lp->tx_irq, dev);
1082 free_irq(lp->ovr_irq, dev);
1083 free_irq(lp->und_irq, dev);
1084
1085 return 0;
1086 }
1087
1088 static const struct net_device_ops korina_netdev_ops = {
1089 .ndo_open = korina_open,
1090 .ndo_stop = korina_close,
1091 .ndo_start_xmit = korina_send_packet,
1092 .ndo_set_multicast_list = korina_multicast_list,
1093 .ndo_tx_timeout = korina_tx_timeout,
1094 .ndo_do_ioctl = korina_ioctl,
1095 .ndo_change_mtu = eth_change_mtu,
1096 .ndo_validate_addr = eth_validate_addr,
1097 .ndo_set_mac_address = eth_mac_addr,
1098 #ifdef CONFIG_NET_POLL_CONTROLLER
1099 .ndo_poll_controller = korina_poll_controller,
1100 #endif
1101 };
1102
1103 static int korina_probe(struct platform_device *pdev)
1104 {
1105 struct korina_device *bif = platform_get_drvdata(pdev);
1106 struct korina_private *lp;
1107 struct net_device *dev;
1108 struct resource *r;
1109 int rc;
1110
1111 dev = alloc_etherdev(sizeof(struct korina_private));
1112 if (!dev) {
1113 printk(KERN_ERR DRV_NAME ": alloc_etherdev failed\n");
1114 return -ENOMEM;
1115 }
1116 SET_NETDEV_DEV(dev, &pdev->dev);
1117 lp = netdev_priv(dev);
1118
1119 bif->dev = dev;
1120 memcpy(dev->dev_addr, bif->mac, 6);
1121
1122 lp->rx_irq = platform_get_irq_byname(pdev, "korina_rx");
1123 lp->tx_irq = platform_get_irq_byname(pdev, "korina_tx");
1124 lp->ovr_irq = platform_get_irq_byname(pdev, "korina_ovr");
1125 lp->und_irq = platform_get_irq_byname(pdev, "korina_und");
1126
1127 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_regs");
1128 dev->base_addr = r->start;
1129 lp->eth_regs = ioremap_nocache(r->start, resource_size(r));
1130 if (!lp->eth_regs) {
1131 printk(KERN_ERR DRV_NAME ": cannot remap registers\n");
1132 rc = -ENXIO;
1133 goto probe_err_out;
1134 }
1135
1136 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_rx");
1137 lp->rx_dma_regs = ioremap_nocache(r->start, resource_size(r));
1138 if (!lp->rx_dma_regs) {
1139 printk(KERN_ERR DRV_NAME ": cannot remap Rx DMA registers\n");
1140 rc = -ENXIO;
1141 goto probe_err_dma_rx;
1142 }
1143
1144 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_tx");
1145 lp->tx_dma_regs = ioremap_nocache(r->start, resource_size(r));
1146 if (!lp->tx_dma_regs) {
1147 printk(KERN_ERR DRV_NAME ": cannot remap Tx DMA registers\n");
1148 rc = -ENXIO;
1149 goto probe_err_dma_tx;
1150 }
1151
1152 lp->td_ring = kmalloc(TD_RING_SIZE + RD_RING_SIZE, GFP_KERNEL);
1153 if (!lp->td_ring) {
1154 printk(KERN_ERR DRV_NAME ": cannot allocate descriptors\n");
1155 rc = -ENXIO;
1156 goto probe_err_td_ring;
1157 }
1158
1159 dma_cache_inv((unsigned long)(lp->td_ring),
1160 TD_RING_SIZE + RD_RING_SIZE);
1161
1162 /* now convert TD_RING pointer to KSEG1 */
1163 lp->td_ring = (struct dma_desc *)KSEG1ADDR(lp->td_ring);
1164 lp->rd_ring = &lp->td_ring[KORINA_NUM_TDS];
1165
1166 spin_lock_init(&lp->lock);
1167 /* just use the rx dma irq */
1168 dev->irq = lp->rx_irq;
1169 lp->dev = dev;
1170
1171 dev->netdev_ops = &korina_netdev_ops;
1172 dev->ethtool_ops = &netdev_ethtool_ops;
1173 dev->watchdog_timeo = TX_TIMEOUT;
1174 netif_napi_add(dev, &lp->napi, korina_poll, 64);
1175
1176 lp->phy_addr = (((lp->rx_irq == 0x2c? 1:0) << 8) | 0x05);
1177 lp->mii_if.dev = dev;
1178 lp->mii_if.mdio_read = mdio_read;
1179 lp->mii_if.mdio_write = mdio_write;
1180 lp->mii_if.phy_id = lp->phy_addr;
1181 lp->mii_if.phy_id_mask = 0x1f;
1182 lp->mii_if.reg_num_mask = 0x1f;
1183
1184 rc = register_netdev(dev);
1185 if (rc < 0) {
1186 printk(KERN_ERR DRV_NAME
1187 ": cannot register net device: %d\n", rc);
1188 goto probe_err_register;
1189 }
1190 setup_timer(&lp->media_check_timer, korina_poll_media, (unsigned long) dev);
1191
1192 INIT_WORK(&lp->restart_task, korina_restart_task);
1193
1194 printk(KERN_INFO "%s: " DRV_NAME "-" DRV_VERSION " " DRV_RELDATE "\n",
1195 dev->name);
1196 out:
1197 return rc;
1198
1199 probe_err_register:
1200 kfree(lp->td_ring);
1201 probe_err_td_ring:
1202 iounmap(lp->tx_dma_regs);
1203 probe_err_dma_tx:
1204 iounmap(lp->rx_dma_regs);
1205 probe_err_dma_rx:
1206 iounmap(lp->eth_regs);
1207 probe_err_out:
1208 free_netdev(dev);
1209 goto out;
1210 }
1211
1212 static int korina_remove(struct platform_device *pdev)
1213 {
1214 struct korina_device *bif = platform_get_drvdata(pdev);
1215 struct korina_private *lp = netdev_priv(bif->dev);
1216
1217 iounmap(lp->eth_regs);
1218 iounmap(lp->rx_dma_regs);
1219 iounmap(lp->tx_dma_regs);
1220
1221 platform_set_drvdata(pdev, NULL);
1222 unregister_netdev(bif->dev);
1223 free_netdev(bif->dev);
1224
1225 return 0;
1226 }
1227
1228 static struct platform_driver korina_driver = {
1229 .driver.name = "korina",
1230 .probe = korina_probe,
1231 .remove = korina_remove,
1232 };
1233
1234 static int __init korina_init_module(void)
1235 {
1236 return platform_driver_register(&korina_driver);
1237 }
1238
1239 static void korina_cleanup_module(void)
1240 {
1241 return platform_driver_unregister(&korina_driver);
1242 }
1243
1244 module_init(korina_init_module);
1245 module_exit(korina_cleanup_module);
1246
1247 MODULE_AUTHOR("Philip Rischel <rischelp@idt.com>");
1248 MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
1249 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
1250 MODULE_DESCRIPTION("IDT RC32434 (Korina) Ethernet driver");
1251 MODULE_LICENSE("GPL");
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