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sparc32: Fix obvious build issues for tftpboot.img build.
[linux-2.6/btrfs-unstable.git] / drivers / net / korina.c
blobb4cf602c32b079a71e495518ce57653f760d6122
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 net_device *dev;
139 int phy_addr;
140 };
141
142 extern unsigned int idt_cpu_freq;
143
144 static inline void korina_start_dma(struct dma_reg *ch, u32 dma_addr)
145 {
146 writel(0, &ch->dmandptr);
147 writel(dma_addr, &ch->dmadptr);
148 }
149
150 static inline void korina_abort_dma(struct net_device *dev,
151 struct dma_reg *ch)
152 {
153 if (readl(&ch->dmac) & DMA_CHAN_RUN_BIT) {
154 writel(0x10, &ch->dmac);
155
156 while (!(readl(&ch->dmas) & DMA_STAT_HALT))
157 dev->trans_start = jiffies;
158
159 writel(0, &ch->dmas);
160 }
161
162 writel(0, &ch->dmadptr);
163 writel(0, &ch->dmandptr);
164 }
165
166 static inline void korina_chain_dma(struct dma_reg *ch, u32 dma_addr)
167 {
168 writel(dma_addr, &ch->dmandptr);
169 }
170
171 static void korina_abort_tx(struct net_device *dev)
172 {
173 struct korina_private *lp = netdev_priv(dev);
174
175 korina_abort_dma(dev, lp->tx_dma_regs);
176 }
177
178 static void korina_abort_rx(struct net_device *dev)
179 {
180 struct korina_private *lp = netdev_priv(dev);
181
182 korina_abort_dma(dev, lp->rx_dma_regs);
183 }
184
185 static void korina_start_rx(struct korina_private *lp,
186 struct dma_desc *rd)
187 {
188 korina_start_dma(lp->rx_dma_regs, CPHYSADDR(rd));
189 }
190
191 static void korina_chain_rx(struct korina_private *lp,
192 struct dma_desc *rd)
193 {
194 korina_chain_dma(lp->rx_dma_regs, CPHYSADDR(rd));
195 }
196
197 /* transmit packet */
198 static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
199 {
200 struct korina_private *lp = netdev_priv(dev);
201 unsigned long flags;
202 u32 length;
203 u32 chain_prev, chain_next;
204 struct dma_desc *td;
205
206 spin_lock_irqsave(&lp->lock, flags);
207
208 td = &lp->td_ring[lp->tx_chain_tail];
209
210 /* stop queue when full, drop pkts if queue already full */
211 if (lp->tx_count >= (KORINA_NUM_TDS - 2)) {
212 lp->tx_full = 1;
213
214 if (lp->tx_count == (KORINA_NUM_TDS - 2))
215 netif_stop_queue(dev);
216 else {
217 dev->stats.tx_dropped++;
218 dev_kfree_skb_any(skb);
219 spin_unlock_irqrestore(&lp->lock, flags);
220
221 return NETDEV_TX_BUSY;
222 }
223 }
224
225 lp->tx_count++;
226
227 lp->tx_skb[lp->tx_chain_tail] = skb;
228
229 length = skb->len;
230 dma_cache_wback((u32)skb->data, skb->len);
231
232 /* Setup the transmit descriptor. */
233 dma_cache_inv((u32) td, sizeof(*td));
234 td->ca = CPHYSADDR(skb->data);
235 chain_prev = (lp->tx_chain_tail - 1) & KORINA_TDS_MASK;
236 chain_next = (lp->tx_chain_tail + 1) & KORINA_TDS_MASK;
237
238 if (readl(&(lp->tx_dma_regs->dmandptr)) == 0) {
239 if (lp->tx_chain_status == desc_empty) {
240 /* Update tail */
241 td->control = DMA_COUNT(length) |
242 DMA_DESC_COF | DMA_DESC_IOF;
243 /* Move tail */
244 lp->tx_chain_tail = chain_next;
245 /* Write to NDPTR */
246 writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
247 &lp->tx_dma_regs->dmandptr);
248 /* Move head to tail */
249 lp->tx_chain_head = lp->tx_chain_tail;
250 } else {
251 /* Update tail */
252 td->control = DMA_COUNT(length) |
253 DMA_DESC_COF | DMA_DESC_IOF;
254 /* Link to prev */
255 lp->td_ring[chain_prev].control &=
256 ~DMA_DESC_COF;
257 /* Link to prev */
258 lp->td_ring[chain_prev].link = CPHYSADDR(td);
259 /* Move tail */
260 lp->tx_chain_tail = chain_next;
261 /* Write to NDPTR */
262 writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
263 &(lp->tx_dma_regs->dmandptr));
264 /* Move head to tail */
265 lp->tx_chain_head = lp->tx_chain_tail;
266 lp->tx_chain_status = desc_empty;
267 }
268 } else {
269 if (lp->tx_chain_status == desc_empty) {
270 /* Update tail */
271 td->control = DMA_COUNT(length) |
272 DMA_DESC_COF | DMA_DESC_IOF;
273 /* Move tail */
274 lp->tx_chain_tail = chain_next;
275 lp->tx_chain_status = desc_filled;
276 } else {
277 /* Update tail */
278 td->control = DMA_COUNT(length) |
279 DMA_DESC_COF | DMA_DESC_IOF;
280 lp->td_ring[chain_prev].control &=
281 ~DMA_DESC_COF;
282 lp->td_ring[chain_prev].link = CPHYSADDR(td);
283 lp->tx_chain_tail = chain_next;
284 }
285 }
286 dma_cache_wback((u32) td, sizeof(*td));
287
288 dev->trans_start = jiffies;
289 spin_unlock_irqrestore(&lp->lock, flags);
290
291 return NETDEV_TX_OK;
292 }
293
294 static int mdio_read(struct net_device *dev, int mii_id, int reg)
295 {
296 struct korina_private *lp = netdev_priv(dev);
297 int ret;
298
299 mii_id = ((lp->rx_irq == 0x2c ? 1 : 0) << 8);
300
301 writel(0, &lp->eth_regs->miimcfg);
302 writel(0, &lp->eth_regs->miimcmd);
303 writel(mii_id | reg, &lp->eth_regs->miimaddr);
304 writel(ETH_MII_CMD_SCN, &lp->eth_regs->miimcmd);
305
306 ret = (int)(readl(&lp->eth_regs->miimrdd));
307 return ret;
308 }
309
310 static void mdio_write(struct net_device *dev, int mii_id, int reg, int val)
311 {
312 struct korina_private *lp = netdev_priv(dev);
313
314 mii_id = ((lp->rx_irq == 0x2c ? 1 : 0) << 8);
315
316 writel(0, &lp->eth_regs->miimcfg);
317 writel(1, &lp->eth_regs->miimcmd);
318 writel(mii_id | reg, &lp->eth_regs->miimaddr);
319 writel(ETH_MII_CMD_SCN, &lp->eth_regs->miimcmd);
320 writel(val, &lp->eth_regs->miimwtd);
321 }
322
323 /* Ethernet Rx DMA interrupt */
324 static irqreturn_t korina_rx_dma_interrupt(int irq, void *dev_id)
325 {
326 struct net_device *dev = dev_id;
327 struct korina_private *lp = netdev_priv(dev);
328 u32 dmas, dmasm;
329 irqreturn_t retval;
330
331 dmas = readl(&lp->rx_dma_regs->dmas);
332 if (dmas & (DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR)) {
333 dmasm = readl(&lp->rx_dma_regs->dmasm);
334 writel(dmasm | (DMA_STAT_DONE |
335 DMA_STAT_HALT | DMA_STAT_ERR),
336 &lp->rx_dma_regs->dmasm);
337
338 napi_schedule(&lp->napi);
339
340 if (dmas & DMA_STAT_ERR)
341 printk(KERN_ERR DRV_NAME "%s: DMA error\n", dev->name);
342
343 retval = IRQ_HANDLED;
344 } else
345 retval = IRQ_NONE;
346
347 return retval;
348 }
349
350 static int korina_rx(struct net_device *dev, int limit)
351 {
352 struct korina_private *lp = netdev_priv(dev);
353 struct dma_desc *rd = &lp->rd_ring[lp->rx_next_done];
354 struct sk_buff *skb, *skb_new;
355 u8 *pkt_buf;
356 u32 devcs, pkt_len, dmas;
357 int count;
358
359 dma_cache_inv((u32)rd, sizeof(*rd));
360
361 for (count = 0; count < limit; count++) {
362 skb = lp->rx_skb[lp->rx_next_done];
363 skb_new = NULL;
364
365 devcs = rd->devcs;
366
367 if ((KORINA_RBSIZE - (u32)DMA_COUNT(rd->control)) == 0)
368 break;
369
370 /* Update statistics counters */
371 if (devcs & ETH_RX_CRC)
372 dev->stats.rx_crc_errors++;
373 if (devcs & ETH_RX_LOR)
374 dev->stats.rx_length_errors++;
375 if (devcs & ETH_RX_LE)
376 dev->stats.rx_length_errors++;
377 if (devcs & ETH_RX_OVR)
378 dev->stats.rx_over_errors++;
379 if (devcs & ETH_RX_CV)
380 dev->stats.rx_frame_errors++;
381 if (devcs & ETH_RX_CES)
382 dev->stats.rx_length_errors++;
383 if (devcs & ETH_RX_MP)
384 dev->stats.multicast++;
385
386 if ((devcs & ETH_RX_LD) != ETH_RX_LD) {
387 /* check that this is a whole packet
388 * WARNING: DMA_FD bit incorrectly set
389 * in Rc32434 (errata ref #077) */
390 dev->stats.rx_errors++;
391 dev->stats.rx_dropped++;
392 } else if ((devcs & ETH_RX_ROK)) {
393 pkt_len = RCVPKT_LENGTH(devcs);
394
395 /* must be the (first and) last
396 * descriptor then */
397 pkt_buf = (u8 *)lp->rx_skb[lp->rx_next_done]->data;
398
399 /* invalidate the cache */
400 dma_cache_inv((unsigned long)pkt_buf, pkt_len - 4);
401
402 /* Malloc up new buffer. */
403 skb_new = netdev_alloc_skb(dev, KORINA_RBSIZE + 2);
404
405 if (!skb_new)
406 break;
407 /* Do not count the CRC */
408 skb_put(skb, pkt_len - 4);
409 skb->protocol = eth_type_trans(skb, dev);
410
411 /* Pass the packet to upper layers */
412 netif_receive_skb(skb);
413 dev->stats.rx_packets++;
414 dev->stats.rx_bytes += pkt_len;
415
416 /* Update the mcast stats */
417 if (devcs & ETH_RX_MP)
418 dev->stats.multicast++;
419
420 /* 16 bit align */
421 skb_reserve(skb_new, 2);
422
423 lp->rx_skb[lp->rx_next_done] = skb_new;
424 }
425
426 rd->devcs = 0;
427
428 /* Restore descriptor's curr_addr */
429 if (skb_new)
430 rd->ca = CPHYSADDR(skb_new->data);
431 else
432 rd->ca = CPHYSADDR(skb->data);
433
434 rd->control = DMA_COUNT(KORINA_RBSIZE) |
435 DMA_DESC_COD | DMA_DESC_IOD;
436 lp->rd_ring[(lp->rx_next_done - 1) &
437 KORINA_RDS_MASK].control &=
438 ~DMA_DESC_COD;
439
440 lp->rx_next_done = (lp->rx_next_done + 1) & KORINA_RDS_MASK;
441 dma_cache_wback((u32)rd, sizeof(*rd));
442 rd = &lp->rd_ring[lp->rx_next_done];
443 writel(~DMA_STAT_DONE, &lp->rx_dma_regs->dmas);
444 }
445
446 dmas = readl(&lp->rx_dma_regs->dmas);
447
448 if (dmas & DMA_STAT_HALT) {
449 writel(~(DMA_STAT_HALT | DMA_STAT_ERR),
450 &lp->rx_dma_regs->dmas);
451
452 lp->dma_halt_cnt++;
453 rd->devcs = 0;
454 skb = lp->rx_skb[lp->rx_next_done];
455 rd->ca = CPHYSADDR(skb->data);
456 dma_cache_wback((u32)rd, sizeof(*rd));
457 korina_chain_rx(lp, rd);
458 }
459
460 return count;
461 }
462
463 static int korina_poll(struct napi_struct *napi, int budget)
464 {
465 struct korina_private *lp =
466 container_of(napi, struct korina_private, napi);
467 struct net_device *dev = lp->dev;
468 int work_done;
469
470 work_done = korina_rx(dev, budget);
471 if (work_done < budget) {
472 napi_complete(napi);
473
474 writel(readl(&lp->rx_dma_regs->dmasm) &
475 ~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
476 &lp->rx_dma_regs->dmasm);
477 }
478 return work_done;
479 }
480
481 /*
482 * Set or clear the multicast filter for this adaptor.
483 */
484 static void korina_multicast_list(struct net_device *dev)
485 {
486 struct korina_private *lp = netdev_priv(dev);
487 unsigned long flags;
488 struct dev_mc_list *dmi = dev->mc_list;
489 u32 recognise = ETH_ARC_AB; /* always accept broadcasts */
490 int i;
491
492 /* Set promiscuous mode */
493 if (dev->flags & IFF_PROMISC)
494 recognise |= ETH_ARC_PRO;
495
496 else if ((dev->flags & IFF_ALLMULTI) || (dev->mc_count > 4))
497 /* All multicast and broadcast */
498 recognise |= ETH_ARC_AM;
499
500 /* Build the hash table */
501 if (dev->mc_count > 4) {
502 u16 hash_table[4];
503 u32 crc;
504
505 for (i = 0; i < 4; i++)
506 hash_table[i] = 0;
507
508 for (i = 0; i < dev->mc_count; i++) {
509 char *addrs = dmi->dmi_addr;
510
511 dmi = dmi->next;
512
513 if (!(*addrs & 1))
514 continue;
515
516 crc = ether_crc_le(6, addrs);
517 crc >>= 26;
518 hash_table[crc >> 4] |= 1 << (15 - (crc & 0xf));
519 }
520 /* Accept filtered multicast */
521 recognise |= ETH_ARC_AFM;
522
523 /* Fill the MAC hash tables with their values */
524 writel((u32)(hash_table[1] << 16 | hash_table[0]),
525 &lp->eth_regs->ethhash0);
526 writel((u32)(hash_table[3] << 16 | hash_table[2]),
527 &lp->eth_regs->ethhash1);
528 }
529
530 spin_lock_irqsave(&lp->lock, flags);
531 writel(recognise, &lp->eth_regs->etharc);
532 spin_unlock_irqrestore(&lp->lock, flags);
533 }
534
535 static void korina_tx(struct net_device *dev)
536 {
537 struct korina_private *lp = netdev_priv(dev);
538 struct dma_desc *td = &lp->td_ring[lp->tx_next_done];
539 u32 devcs;
540 u32 dmas;
541
542 spin_lock(&lp->lock);
543
544 /* Process all desc that are done */
545 while (IS_DMA_FINISHED(td->control)) {
546 if (lp->tx_full == 1) {
547 netif_wake_queue(dev);
548 lp->tx_full = 0;
549 }
550
551 devcs = lp->td_ring[lp->tx_next_done].devcs;
552 if ((devcs & (ETH_TX_FD | ETH_TX_LD)) !=
553 (ETH_TX_FD | ETH_TX_LD)) {
554 dev->stats.tx_errors++;
555 dev->stats.tx_dropped++;
556
557 /* Should never happen */
558 printk(KERN_ERR DRV_NAME "%s: split tx ignored\n",
559 dev->name);
560 } else if (devcs & ETH_TX_TOK) {
561 dev->stats.tx_packets++;
562 dev->stats.tx_bytes +=
563 lp->tx_skb[lp->tx_next_done]->len;
564 } else {
565 dev->stats.tx_errors++;
566 dev->stats.tx_dropped++;
567
568 /* Underflow */
569 if (devcs & ETH_TX_UND)
570 dev->stats.tx_fifo_errors++;
571
572 /* Oversized frame */
573 if (devcs & ETH_TX_OF)
574 dev->stats.tx_aborted_errors++;
575
576 /* Excessive deferrals */
577 if (devcs & ETH_TX_ED)
578 dev->stats.tx_carrier_errors++;
579
580 /* Collisions: medium busy */
581 if (devcs & ETH_TX_EC)
582 dev->stats.collisions++;
583
584 /* Late collision */
585 if (devcs & ETH_TX_LC)
586 dev->stats.tx_window_errors++;
587 }
588
589 /* We must always free the original skb */
590 if (lp->tx_skb[lp->tx_next_done]) {
591 dev_kfree_skb_any(lp->tx_skb[lp->tx_next_done]);
592 lp->tx_skb[lp->tx_next_done] = NULL;
593 }
594
595 lp->td_ring[lp->tx_next_done].control = DMA_DESC_IOF;
596 lp->td_ring[lp->tx_next_done].devcs = ETH_TX_FD | ETH_TX_LD;
597 lp->td_ring[lp->tx_next_done].link = 0;
598 lp->td_ring[lp->tx_next_done].ca = 0;
599 lp->tx_count--;
600
601 /* Go on to next transmission */
602 lp->tx_next_done = (lp->tx_next_done + 1) & KORINA_TDS_MASK;
603 td = &lp->td_ring[lp->tx_next_done];
604
605 }
606
607 /* Clear the DMA status register */
608 dmas = readl(&lp->tx_dma_regs->dmas);
609 writel(~dmas, &lp->tx_dma_regs->dmas);
610
611 writel(readl(&lp->tx_dma_regs->dmasm) &
612 ~(DMA_STAT_FINI | DMA_STAT_ERR),
613 &lp->tx_dma_regs->dmasm);
614
615 spin_unlock(&lp->lock);
616 }
617
618 static irqreturn_t
619 korina_tx_dma_interrupt(int irq, void *dev_id)
620 {
621 struct net_device *dev = dev_id;
622 struct korina_private *lp = netdev_priv(dev);
623 u32 dmas, dmasm;
624 irqreturn_t retval;
625
626 dmas = readl(&lp->tx_dma_regs->dmas);
627
628 if (dmas & (DMA_STAT_FINI | DMA_STAT_ERR)) {
629 dmasm = readl(&lp->tx_dma_regs->dmasm);
630 writel(dmasm | (DMA_STAT_FINI | DMA_STAT_ERR),
631 &lp->tx_dma_regs->dmasm);
632
633 korina_tx(dev);
634
635 if (lp->tx_chain_status == desc_filled &&
636 (readl(&(lp->tx_dma_regs->dmandptr)) == 0)) {
637 writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
638 &(lp->tx_dma_regs->dmandptr));
639 lp->tx_chain_status = desc_empty;
640 lp->tx_chain_head = lp->tx_chain_tail;
641 dev->trans_start = jiffies;
642 }
643 if (dmas & DMA_STAT_ERR)
644 printk(KERN_ERR DRV_NAME "%s: DMA error\n", dev->name);
645
646 retval = IRQ_HANDLED;
647 } else
648 retval = IRQ_NONE;
649
650 return retval;
651 }
652
653
654 static void korina_check_media(struct net_device *dev, unsigned int init_media)
655 {
656 struct korina_private *lp = netdev_priv(dev);
657
658 mii_check_media(&lp->mii_if, 0, init_media);
659
660 if (lp->mii_if.full_duplex)
661 writel(readl(&lp->eth_regs->ethmac2) | ETH_MAC2_FD,
662 &lp->eth_regs->ethmac2);
663 else
664 writel(readl(&lp->eth_regs->ethmac2) & ~ETH_MAC2_FD,
665 &lp->eth_regs->ethmac2);
666 }
667
668 static void korina_poll_media(unsigned long data)
669 {
670 struct net_device *dev = (struct net_device *) data;
671 struct korina_private *lp = netdev_priv(dev);
672
673 korina_check_media(dev, 0);
674 mod_timer(&lp->media_check_timer, jiffies + HZ);
675 }
676
677 static void korina_set_carrier(struct mii_if_info *mii)
678 {
679 if (mii->force_media) {
680 /* autoneg is off: Link is always assumed to be up */
681 if (!netif_carrier_ok(mii->dev))
682 netif_carrier_on(mii->dev);
683 } else /* Let MMI library update carrier status */
684 korina_check_media(mii->dev, 0);
685 }
686
687 static int korina_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
688 {
689 struct korina_private *lp = netdev_priv(dev);
690 struct mii_ioctl_data *data = if_mii(rq);
691 int rc;
692
693 if (!netif_running(dev))
694 return -EINVAL;
695 spin_lock_irq(&lp->lock);
696 rc = generic_mii_ioctl(&lp->mii_if, data, cmd, NULL);
697 spin_unlock_irq(&lp->lock);
698 korina_set_carrier(&lp->mii_if);
699
700 return rc;
701 }
702
703 /* ethtool helpers */
704 static void netdev_get_drvinfo(struct net_device *dev,
705 struct ethtool_drvinfo *info)
706 {
707 struct korina_private *lp = netdev_priv(dev);
708
709 strcpy(info->driver, DRV_NAME);
710 strcpy(info->version, DRV_VERSION);
711 strcpy(info->bus_info, lp->dev->name);
712 }
713
714 static int netdev_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
715 {
716 struct korina_private *lp = netdev_priv(dev);
717 int rc;
718
719 spin_lock_irq(&lp->lock);
720 rc = mii_ethtool_gset(&lp->mii_if, cmd);
721 spin_unlock_irq(&lp->lock);
722
723 return rc;
724 }
725
726 static int netdev_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
727 {
728 struct korina_private *lp = netdev_priv(dev);
729 int rc;
730
731 spin_lock_irq(&lp->lock);
732 rc = mii_ethtool_sset(&lp->mii_if, cmd);
733 spin_unlock_irq(&lp->lock);
734 korina_set_carrier(&lp->mii_if);
735
736 return rc;
737 }
738
739 static u32 netdev_get_link(struct net_device *dev)
740 {
741 struct korina_private *lp = netdev_priv(dev);
742
743 return mii_link_ok(&lp->mii_if);
744 }
745
746 static struct ethtool_ops netdev_ethtool_ops = {
747 .get_drvinfo = netdev_get_drvinfo,
748 .get_settings = netdev_get_settings,
749 .set_settings = netdev_set_settings,
750 .get_link = netdev_get_link,
751 };
752
753 static void korina_alloc_ring(struct net_device *dev)
754 {
755 struct korina_private *lp = netdev_priv(dev);
756 struct sk_buff *skb;
757 int i;
758
759 /* Initialize the transmit descriptors */
760 for (i = 0; i < KORINA_NUM_TDS; i++) {
761 lp->td_ring[i].control = DMA_DESC_IOF;
762 lp->td_ring[i].devcs = ETH_TX_FD | ETH_TX_LD;
763 lp->td_ring[i].ca = 0;
764 lp->td_ring[i].link = 0;
765 }
766 lp->tx_next_done = lp->tx_chain_head = lp->tx_chain_tail =
767 lp->tx_full = lp->tx_count = 0;
768 lp->tx_chain_status = desc_empty;
769
770 /* Initialize the receive descriptors */
771 for (i = 0; i < KORINA_NUM_RDS; i++) {
772 skb = dev_alloc_skb(KORINA_RBSIZE + 2);
773 if (!skb)
774 break;
775 skb_reserve(skb, 2);
776 lp->rx_skb[i] = skb;
777 lp->rd_ring[i].control = DMA_DESC_IOD |
778 DMA_COUNT(KORINA_RBSIZE);
779 lp->rd_ring[i].devcs = 0;
780 lp->rd_ring[i].ca = CPHYSADDR(skb->data);
781 lp->rd_ring[i].link = CPHYSADDR(&lp->rd_ring[i+1]);
782 }
783
784 /* loop back receive descriptors, so the last
785 * descriptor points to the first one */
786 lp->rd_ring[i - 1].link = CPHYSADDR(&lp->rd_ring[0]);
787 lp->rd_ring[i - 1].control |= DMA_DESC_COD;
788
789 lp->rx_next_done = 0;
790 lp->rx_chain_head = 0;
791 lp->rx_chain_tail = 0;
792 lp->rx_chain_status = desc_empty;
793 }
794
795 static void korina_free_ring(struct net_device *dev)
796 {
797 struct korina_private *lp = netdev_priv(dev);
798 int i;
799
800 for (i = 0; i < KORINA_NUM_RDS; i++) {
801 lp->rd_ring[i].control = 0;
802 if (lp->rx_skb[i])
803 dev_kfree_skb_any(lp->rx_skb[i]);
804 lp->rx_skb[i] = NULL;
805 }
806
807 for (i = 0; i < KORINA_NUM_TDS; i++) {
808 lp->td_ring[i].control = 0;
809 if (lp->tx_skb[i])
810 dev_kfree_skb_any(lp->tx_skb[i]);
811 lp->tx_skb[i] = NULL;
812 }
813 }
814
815 /*
816 * Initialize the RC32434 ethernet controller.
817 */
818 static int korina_init(struct net_device *dev)
819 {
820 struct korina_private *lp = netdev_priv(dev);
821
822 /* Disable DMA */
823 korina_abort_tx(dev);
824 korina_abort_rx(dev);
825
826 /* reset ethernet logic */
827 writel(0, &lp->eth_regs->ethintfc);
828 while ((readl(&lp->eth_regs->ethintfc) & ETH_INT_FC_RIP))
829 dev->trans_start = jiffies;
830
831 /* Enable Ethernet Interface */
832 writel(ETH_INT_FC_EN, &lp->eth_regs->ethintfc);
833
834 /* Allocate rings */
835 korina_alloc_ring(dev);
836
837 writel(0, &lp->rx_dma_regs->dmas);
838 /* Start Rx DMA */
839 korina_start_rx(lp, &lp->rd_ring[0]);
840
841 writel(readl(&lp->tx_dma_regs->dmasm) &
842 ~(DMA_STAT_FINI | DMA_STAT_ERR),
843 &lp->tx_dma_regs->dmasm);
844 writel(readl(&lp->rx_dma_regs->dmasm) &
845 ~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
846 &lp->rx_dma_regs->dmasm);
847
848 /* Accept only packets destined for this Ethernet device address */
849 writel(ETH_ARC_AB, &lp->eth_regs->etharc);
850
851 /* Set all Ether station address registers to their initial values */
852 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal0);
853 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah0);
854
855 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal1);
856 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah1);
857
858 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal2);
859 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah2);
860
861 writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal3);
862 writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah3);
863
864
865 /* Frame Length Checking, Pad Enable, CRC Enable, Full Duplex set */
866 writel(ETH_MAC2_PE | ETH_MAC2_CEN | ETH_MAC2_FD,
867 &lp->eth_regs->ethmac2);
868
869 /* Back to back inter-packet-gap */
870 writel(0x15, &lp->eth_regs->ethipgt);
871 /* Non - Back to back inter-packet-gap */
872 writel(0x12, &lp->eth_regs->ethipgr);
873
874 /* Management Clock Prescaler Divisor
875 * Clock independent setting */
876 writel(((idt_cpu_freq) / MII_CLOCK + 1) & ~1,
877 &lp->eth_regs->ethmcp);
878
879 /* don't transmit until fifo contains 48b */
880 writel(48, &lp->eth_regs->ethfifott);
881
882 writel(ETH_MAC1_RE, &lp->eth_regs->ethmac1);
883
884 napi_enable(&lp->napi);
885 netif_start_queue(dev);
886
887 return 0;
888 }
889
890 /*
891 * Restart the RC32434 ethernet controller.
892 * FIXME: check the return status where we call it
893 */
894 static int korina_restart(struct net_device *dev)
895 {
896 struct korina_private *lp = netdev_priv(dev);
897 int ret;
898
899 /*
900 * Disable interrupts
901 */
902 disable_irq(lp->rx_irq);
903 disable_irq(lp->tx_irq);
904 disable_irq(lp->ovr_irq);
905 disable_irq(lp->und_irq);
906
907 writel(readl(&lp->tx_dma_regs->dmasm) |
908 DMA_STAT_FINI | DMA_STAT_ERR,
909 &lp->tx_dma_regs->dmasm);
910 writel(readl(&lp->rx_dma_regs->dmasm) |
911 DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR,
912 &lp->rx_dma_regs->dmasm);
913
914 korina_free_ring(dev);
915
916 napi_disable(&lp->napi);
917
918 ret = korina_init(dev);
919 if (ret < 0) {
920 printk(KERN_ERR DRV_NAME "%s: cannot restart device\n",
921 dev->name);
922 return ret;
923 }
924 korina_multicast_list(dev);
925
926 enable_irq(lp->und_irq);
927 enable_irq(lp->ovr_irq);
928 enable_irq(lp->tx_irq);
929 enable_irq(lp->rx_irq);
930
931 return ret;
932 }
933
934 static void korina_clear_and_restart(struct net_device *dev, u32 value)
935 {
936 struct korina_private *lp = netdev_priv(dev);
937
938 netif_stop_queue(dev);
939 writel(value, &lp->eth_regs->ethintfc);
940 korina_restart(dev);
941 }
942
943 /* Ethernet Tx Underflow interrupt */
944 static irqreturn_t korina_und_interrupt(int irq, void *dev_id)
945 {
946 struct net_device *dev = dev_id;
947 struct korina_private *lp = netdev_priv(dev);
948 unsigned int und;
949
950 spin_lock(&lp->lock);
951
952 und = readl(&lp->eth_regs->ethintfc);
953
954 if (und & ETH_INT_FC_UND)
955 korina_clear_and_restart(dev, und & ~ETH_INT_FC_UND);
956
957 spin_unlock(&lp->lock);
958
959 return IRQ_HANDLED;
960 }
961
962 static void korina_tx_timeout(struct net_device *dev)
963 {
964 struct korina_private *lp = netdev_priv(dev);
965 unsigned long flags;
966
967 spin_lock_irqsave(&lp->lock, flags);
968 korina_restart(dev);
969 spin_unlock_irqrestore(&lp->lock, flags);
970 }
971
972 /* Ethernet Rx Overflow interrupt */
973 static irqreturn_t
974 korina_ovr_interrupt(int irq, void *dev_id)
975 {
976 struct net_device *dev = dev_id;
977 struct korina_private *lp = netdev_priv(dev);
978 unsigned int ovr;
979
980 spin_lock(&lp->lock);
981 ovr = readl(&lp->eth_regs->ethintfc);
982
983 if (ovr & ETH_INT_FC_OVR)
984 korina_clear_and_restart(dev, ovr & ~ETH_INT_FC_OVR);
985
986 spin_unlock(&lp->lock);
987
988 return IRQ_HANDLED;
989 }
990
991 #ifdef CONFIG_NET_POLL_CONTROLLER
992 static void korina_poll_controller(struct net_device *dev)
993 {
994 disable_irq(dev->irq);
995 korina_tx_dma_interrupt(dev->irq, dev);
996 enable_irq(dev->irq);
997 }
998 #endif
999
1000 static int korina_open(struct net_device *dev)
1001 {
1002 struct korina_private *lp = netdev_priv(dev);
1003 int ret;
1004
1005 /* Initialize */
1006 ret = korina_init(dev);
1007 if (ret < 0) {
1008 printk(KERN_ERR DRV_NAME "%s: cannot open device\n", dev->name);
1009 goto out;
1010 }
1011
1012 /* Install the interrupt handler
1013 * that handles the Done Finished
1014 * Ovr and Und Events */
1015 ret = request_irq(lp->rx_irq, &korina_rx_dma_interrupt,
1016 IRQF_DISABLED, "Korina ethernet Rx", dev);
1017 if (ret < 0) {
1018 printk(KERN_ERR DRV_NAME "%s: unable to get Rx DMA IRQ %d\n",
1019 dev->name, lp->rx_irq);
1020 goto err_release;
1021 }
1022 ret = request_irq(lp->tx_irq, &korina_tx_dma_interrupt,
1023 IRQF_DISABLED, "Korina ethernet Tx", dev);
1024 if (ret < 0) {
1025 printk(KERN_ERR DRV_NAME "%s: unable to get Tx DMA IRQ %d\n",
1026 dev->name, lp->tx_irq);
1027 goto err_free_rx_irq;
1028 }
1029
1030 /* Install handler for overrun error. */
1031 ret = request_irq(lp->ovr_irq, &korina_ovr_interrupt,
1032 IRQF_DISABLED, "Ethernet Overflow", dev);
1033 if (ret < 0) {
1034 printk(KERN_ERR DRV_NAME"%s: unable to get OVR IRQ %d\n",
1035 dev->name, lp->ovr_irq);
1036 goto err_free_tx_irq;
1037 }
1038
1039 /* Install handler for underflow error. */
1040 ret = request_irq(lp->und_irq, &korina_und_interrupt,
1041 IRQF_DISABLED, "Ethernet Underflow", dev);
1042 if (ret < 0) {
1043 printk(KERN_ERR DRV_NAME "%s: unable to get UND IRQ %d\n",
1044 dev->name, lp->und_irq);
1045 goto err_free_ovr_irq;
1046 }
1047 mod_timer(&lp->media_check_timer, jiffies + 1);
1048 out:
1049 return ret;
1050
1051 err_free_ovr_irq:
1052 free_irq(lp->ovr_irq, dev);
1053 err_free_tx_irq:
1054 free_irq(lp->tx_irq, dev);
1055 err_free_rx_irq:
1056 free_irq(lp->rx_irq, dev);
1057 err_release:
1058 korina_free_ring(dev);
1059 goto out;
1060 }
1061
1062 static int korina_close(struct net_device *dev)
1063 {
1064 struct korina_private *lp = netdev_priv(dev);
1065 u32 tmp;
1066
1067 del_timer(&lp->media_check_timer);
1068
1069 /* Disable interrupts */
1070 disable_irq(lp->rx_irq);
1071 disable_irq(lp->tx_irq);
1072 disable_irq(lp->ovr_irq);
1073 disable_irq(lp->und_irq);
1074
1075 korina_abort_tx(dev);
1076 tmp = readl(&lp->tx_dma_regs->dmasm);
1077 tmp = tmp | DMA_STAT_FINI | DMA_STAT_ERR;
1078 writel(tmp, &lp->tx_dma_regs->dmasm);
1079
1080 korina_abort_rx(dev);
1081 tmp = readl(&lp->rx_dma_regs->dmasm);
1082 tmp = tmp | DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR;
1083 writel(tmp, &lp->rx_dma_regs->dmasm);
1084
1085 korina_free_ring(dev);
1086
1087 napi_disable(&lp->napi);
1088
1089 free_irq(lp->rx_irq, dev);
1090 free_irq(lp->tx_irq, dev);
1091 free_irq(lp->ovr_irq, dev);
1092 free_irq(lp->und_irq, dev);
1093
1094 return 0;
1095 }
1096
1097 static const struct net_device_ops korina_netdev_ops = {
1098 .ndo_open = korina_open,
1099 .ndo_stop = korina_close,
1100 .ndo_start_xmit = korina_send_packet,
1101 .ndo_set_multicast_list = korina_multicast_list,
1102 .ndo_tx_timeout = korina_tx_timeout,
1103 .ndo_do_ioctl = korina_ioctl,
1104 .ndo_change_mtu = eth_change_mtu,
1105 .ndo_validate_addr = eth_validate_addr,
1106 .ndo_set_mac_address = eth_mac_addr,
1107 #ifdef CONFIG_NET_POLL_CONTROLLER
1108 .ndo_poll_controller = korina_poll_controller,
1109 #endif
1110 };
1111
1112 static int korina_probe(struct platform_device *pdev)
1113 {
1114 struct korina_device *bif = platform_get_drvdata(pdev);
1115 struct korina_private *lp;
1116 struct net_device *dev;
1117 struct resource *r;
1118 int rc;
1119
1120 dev = alloc_etherdev(sizeof(struct korina_private));
1121 if (!dev) {
1122 printk(KERN_ERR DRV_NAME ": alloc_etherdev failed\n");
1123 return -ENOMEM;
1124 }
1125 SET_NETDEV_DEV(dev, &pdev->dev);
1126 lp = netdev_priv(dev);
1127
1128 bif->dev = dev;
1129 memcpy(dev->dev_addr, bif->mac, 6);
1130
1131 lp->rx_irq = platform_get_irq_byname(pdev, "korina_rx");
1132 lp->tx_irq = platform_get_irq_byname(pdev, "korina_tx");
1133 lp->ovr_irq = platform_get_irq_byname(pdev, "korina_ovr");
1134 lp->und_irq = platform_get_irq_byname(pdev, "korina_und");
1135
1136 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_regs");
1137 dev->base_addr = r->start;
1138 lp->eth_regs = ioremap_nocache(r->start, r->end - r->start);
1139 if (!lp->eth_regs) {
1140 printk(KERN_ERR DRV_NAME "cannot remap registers\n");
1141 rc = -ENXIO;
1142 goto probe_err_out;
1143 }
1144
1145 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_rx");
1146 lp->rx_dma_regs = ioremap_nocache(r->start, r->end - r->start);
1147 if (!lp->rx_dma_regs) {
1148 printk(KERN_ERR DRV_NAME "cannot remap Rx DMA registers\n");
1149 rc = -ENXIO;
1150 goto probe_err_dma_rx;
1151 }
1152
1153 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_tx");
1154 lp->tx_dma_regs = ioremap_nocache(r->start, r->end - r->start);
1155 if (!lp->tx_dma_regs) {
1156 printk(KERN_ERR DRV_NAME "cannot remap Tx DMA registers\n");
1157 rc = -ENXIO;
1158 goto probe_err_dma_tx;
1159 }
1160
1161 lp->td_ring = kmalloc(TD_RING_SIZE + RD_RING_SIZE, GFP_KERNEL);
1162 if (!lp->td_ring) {
1163 printk(KERN_ERR DRV_NAME "cannot allocate descriptors\n");
1164 rc = -ENXIO;
1165 goto probe_err_td_ring;
1166 }
1167
1168 dma_cache_inv((unsigned long)(lp->td_ring),
1169 TD_RING_SIZE + RD_RING_SIZE);
1170
1171 /* now convert TD_RING pointer to KSEG1 */
1172 lp->td_ring = (struct dma_desc *)KSEG1ADDR(lp->td_ring);
1173 lp->rd_ring = &lp->td_ring[KORINA_NUM_TDS];
1174
1175 spin_lock_init(&lp->lock);
1176 /* just use the rx dma irq */
1177 dev->irq = lp->rx_irq;
1178 lp->dev = dev;
1179
1180 dev->netdev_ops = &korina_netdev_ops;
1181 dev->ethtool_ops = &netdev_ethtool_ops;
1182 dev->watchdog_timeo = TX_TIMEOUT;
1183 netif_napi_add(dev, &lp->napi, korina_poll, 64);
1184
1185 lp->phy_addr = (((lp->rx_irq == 0x2c? 1:0) << 8) | 0x05);
1186 lp->mii_if.dev = dev;
1187 lp->mii_if.mdio_read = mdio_read;
1188 lp->mii_if.mdio_write = mdio_write;
1189 lp->mii_if.phy_id = lp->phy_addr;
1190 lp->mii_if.phy_id_mask = 0x1f;
1191 lp->mii_if.reg_num_mask = 0x1f;
1192
1193 rc = register_netdev(dev);
1194 if (rc < 0) {
1195 printk(KERN_ERR DRV_NAME
1196 ": cannot register net device %d\n", rc);
1197 goto probe_err_register;
1198 }
1199 setup_timer(&lp->media_check_timer, korina_poll_media, (unsigned long) dev);
1200 out:
1201 return rc;
1202
1203 probe_err_register:
1204 kfree(lp->td_ring);
1205 probe_err_td_ring:
1206 iounmap(lp->tx_dma_regs);
1207 probe_err_dma_tx:
1208 iounmap(lp->rx_dma_regs);
1209 probe_err_dma_rx:
1210 iounmap(lp->eth_regs);
1211 probe_err_out:
1212 free_netdev(dev);
1213 goto out;
1214 }
1215
1216 static int korina_remove(struct platform_device *pdev)
1217 {
1218 struct korina_device *bif = platform_get_drvdata(pdev);
1219 struct korina_private *lp = netdev_priv(bif->dev);
1220
1221 iounmap(lp->eth_regs);
1222 iounmap(lp->rx_dma_regs);
1223 iounmap(lp->tx_dma_regs);
1224
1225 platform_set_drvdata(pdev, NULL);
1226 unregister_netdev(bif->dev);
1227 free_netdev(bif->dev);
1228
1229 return 0;
1230 }
1231
1232 static struct platform_driver korina_driver = {
1233 .driver.name = "korina",
1234 .probe = korina_probe,
1235 .remove = korina_remove,
1236 };
1237
1238 static int __init korina_init_module(void)
1239 {
1240 return platform_driver_register(&korina_driver);
1241 }
1242
1243 static void korina_cleanup_module(void)
1244 {
1245 return platform_driver_unregister(&korina_driver);
1246 }
1247
1248 module_init(korina_init_module);
1249 module_exit(korina_cleanup_module);
1250
1251 MODULE_AUTHOR("Philip Rischel <rischelp@idt.com>");
1252 MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
1253 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
1254 MODULE_DESCRIPTION("IDT RC32434 (Korina) Ethernet driver");
1255 MODULE_LICENSE("GPL");
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