xref: /linux/drivers/net/ethernet/apple/bmac.c (revision 9a379e77033f02c4a071891afdf0f0a01eff8ccb)
1 /*
2  * Network device driver for the BMAC ethernet controller on
3  * Apple Powermacs.  Assumes it's under a DBDMA controller.
4  *
5  * Copyright (C) 1998 Randy Gobbel.
6  *
7  * May 1999, Al Viro: proper release of /proc/net/bmac entry, switched to
8  * dynamic procfs inode.
9  */
10 #include <linux/interrupt.h>
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/netdevice.h>
14 #include <linux/etherdevice.h>
15 #include <linux/delay.h>
16 #include <linux/string.h>
17 #include <linux/timer.h>
18 #include <linux/proc_fs.h>
19 #include <linux/init.h>
20 #include <linux/spinlock.h>
21 #include <linux/crc32.h>
22 #include <linux/bitrev.h>
23 #include <linux/ethtool.h>
24 #include <linux/slab.h>
25 #include <asm/prom.h>
26 #include <asm/dbdma.h>
27 #include <asm/io.h>
28 #include <asm/page.h>
29 #include <asm/pgtable.h>
30 #include <asm/machdep.h>
31 #include <asm/pmac_feature.h>
32 #include <asm/macio.h>
33 #include <asm/irq.h>
34 
35 #include "bmac.h"
36 
37 #define trunc_page(x)	((void *)(((unsigned long)(x)) & ~((unsigned long)(PAGE_SIZE - 1))))
38 #define round_page(x)	trunc_page(((unsigned long)(x)) + ((unsigned long)(PAGE_SIZE - 1)))
39 
40 /*
41  * CRC polynomial - used in working out multicast filter bits.
42  */
43 #define ENET_CRCPOLY 0x04c11db7
44 
45 /* switch to use multicast code lifted from sunhme driver */
46 #define SUNHME_MULTICAST
47 
48 #define N_RX_RING	64
49 #define N_TX_RING	32
50 #define MAX_TX_ACTIVE	1
51 #define ETHERCRC	4
52 #define ETHERMINPACKET	64
53 #define ETHERMTU	1500
54 #define RX_BUFLEN	(ETHERMTU + 14 + ETHERCRC + 2)
55 #define TX_TIMEOUT	HZ	/* 1 second */
56 
57 /* Bits in transmit DMA status */
58 #define TX_DMA_ERR	0x80
59 
60 #define XXDEBUG(args)
61 
62 struct bmac_data {
63 	/* volatile struct bmac *bmac; */
64 	struct sk_buff_head *queue;
65 	volatile struct dbdma_regs __iomem *tx_dma;
66 	int tx_dma_intr;
67 	volatile struct dbdma_regs __iomem *rx_dma;
68 	int rx_dma_intr;
69 	volatile struct dbdma_cmd *tx_cmds;	/* xmit dma command list */
70 	volatile struct dbdma_cmd *rx_cmds;	/* recv dma command list */
71 	struct macio_dev *mdev;
72 	int is_bmac_plus;
73 	struct sk_buff *rx_bufs[N_RX_RING];
74 	int rx_fill;
75 	int rx_empty;
76 	struct sk_buff *tx_bufs[N_TX_RING];
77 	int tx_fill;
78 	int tx_empty;
79 	unsigned char tx_fullup;
80 	struct timer_list tx_timeout;
81 	int timeout_active;
82 	int sleeping;
83 	int opened;
84 	unsigned short hash_use_count[64];
85 	unsigned short hash_table_mask[4];
86 	spinlock_t lock;
87 };
88 
89 #if 0 /* Move that to ethtool */
90 
91 typedef struct bmac_reg_entry {
92 	char *name;
93 	unsigned short reg_offset;
94 } bmac_reg_entry_t;
95 
96 #define N_REG_ENTRIES 31
97 
98 static bmac_reg_entry_t reg_entries[N_REG_ENTRIES] = {
99 	{"MEMADD", MEMADD},
100 	{"MEMDATAHI", MEMDATAHI},
101 	{"MEMDATALO", MEMDATALO},
102 	{"TXPNTR", TXPNTR},
103 	{"RXPNTR", RXPNTR},
104 	{"IPG1", IPG1},
105 	{"IPG2", IPG2},
106 	{"ALIMIT", ALIMIT},
107 	{"SLOT", SLOT},
108 	{"PALEN", PALEN},
109 	{"PAPAT", PAPAT},
110 	{"TXSFD", TXSFD},
111 	{"JAM", JAM},
112 	{"TXCFG", TXCFG},
113 	{"TXMAX", TXMAX},
114 	{"TXMIN", TXMIN},
115 	{"PAREG", PAREG},
116 	{"DCNT", DCNT},
117 	{"NCCNT", NCCNT},
118 	{"NTCNT", NTCNT},
119 	{"EXCNT", EXCNT},
120 	{"LTCNT", LTCNT},
121 	{"TXSM", TXSM},
122 	{"RXCFG", RXCFG},
123 	{"RXMAX", RXMAX},
124 	{"RXMIN", RXMIN},
125 	{"FRCNT", FRCNT},
126 	{"AECNT", AECNT},
127 	{"FECNT", FECNT},
128 	{"RXSM", RXSM},
129 	{"RXCV", RXCV}
130 };
131 
132 #endif
133 
134 static unsigned char *bmac_emergency_rxbuf;
135 
136 /*
137  * Number of bytes of private data per BMAC: allow enough for
138  * the rx and tx dma commands plus a branch dma command each,
139  * and another 16 bytes to allow us to align the dma command
140  * buffers on a 16 byte boundary.
141  */
142 #define PRIV_BYTES	(sizeof(struct bmac_data) \
143 	+ (N_RX_RING + N_TX_RING + 4) * sizeof(struct dbdma_cmd) \
144 	+ sizeof(struct sk_buff_head))
145 
146 static int bmac_open(struct net_device *dev);
147 static int bmac_close(struct net_device *dev);
148 static int bmac_transmit_packet(struct sk_buff *skb, struct net_device *dev);
149 static void bmac_set_multicast(struct net_device *dev);
150 static void bmac_reset_and_enable(struct net_device *dev);
151 static void bmac_start_chip(struct net_device *dev);
152 static void bmac_init_chip(struct net_device *dev);
153 static void bmac_init_registers(struct net_device *dev);
154 static void bmac_enable_and_reset_chip(struct net_device *dev);
155 static int bmac_set_address(struct net_device *dev, void *addr);
156 static irqreturn_t bmac_misc_intr(int irq, void *dev_id);
157 static irqreturn_t bmac_txdma_intr(int irq, void *dev_id);
158 static irqreturn_t bmac_rxdma_intr(int irq, void *dev_id);
159 static void bmac_set_timeout(struct net_device *dev);
160 static void bmac_tx_timeout(struct timer_list *t);
161 static int bmac_output(struct sk_buff *skb, struct net_device *dev);
162 static void bmac_start(struct net_device *dev);
163 
164 #define	DBDMA_SET(x)	( ((x) | (x) << 16) )
165 #define	DBDMA_CLEAR(x)	( (x) << 16)
166 
167 static inline void
168 dbdma_st32(volatile __u32 __iomem *a, unsigned long x)
169 {
170 	__asm__ volatile( "stwbrx %0,0,%1" : : "r" (x), "r" (a) : "memory");
171 }
172 
173 static inline unsigned long
174 dbdma_ld32(volatile __u32 __iomem *a)
175 {
176 	__u32 swap;
177 	__asm__ volatile ("lwbrx %0,0,%1" :  "=r" (swap) : "r" (a));
178 	return swap;
179 }
180 
181 static void
182 dbdma_continue(volatile struct dbdma_regs __iomem *dmap)
183 {
184 	dbdma_st32(&dmap->control,
185 		   DBDMA_SET(RUN|WAKE) | DBDMA_CLEAR(PAUSE|DEAD));
186 	eieio();
187 }
188 
189 static void
190 dbdma_reset(volatile struct dbdma_regs __iomem *dmap)
191 {
192 	dbdma_st32(&dmap->control,
193 		   DBDMA_CLEAR(ACTIVE|DEAD|WAKE|FLUSH|PAUSE|RUN));
194 	eieio();
195 	while (dbdma_ld32(&dmap->status) & RUN)
196 		eieio();
197 }
198 
199 static void
200 dbdma_setcmd(volatile struct dbdma_cmd *cp,
201 	     unsigned short cmd, unsigned count, unsigned long addr,
202 	     unsigned long cmd_dep)
203 {
204 	out_le16(&cp->command, cmd);
205 	out_le16(&cp->req_count, count);
206 	out_le32(&cp->phy_addr, addr);
207 	out_le32(&cp->cmd_dep, cmd_dep);
208 	out_le16(&cp->xfer_status, 0);
209 	out_le16(&cp->res_count, 0);
210 }
211 
212 static inline
213 void bmwrite(struct net_device *dev, unsigned long reg_offset, unsigned data )
214 {
215 	out_le16((void __iomem *)dev->base_addr + reg_offset, data);
216 }
217 
218 
219 static inline
220 unsigned short bmread(struct net_device *dev, unsigned long reg_offset )
221 {
222 	return in_le16((void __iomem *)dev->base_addr + reg_offset);
223 }
224 
225 static void
226 bmac_enable_and_reset_chip(struct net_device *dev)
227 {
228 	struct bmac_data *bp = netdev_priv(dev);
229 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
230 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
231 
232 	if (rd)
233 		dbdma_reset(rd);
234 	if (td)
235 		dbdma_reset(td);
236 
237 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 1);
238 }
239 
240 #define MIFDELAY	udelay(10)
241 
242 static unsigned int
243 bmac_mif_readbits(struct net_device *dev, int nb)
244 {
245 	unsigned int val = 0;
246 
247 	while (--nb >= 0) {
248 		bmwrite(dev, MIFCSR, 0);
249 		MIFDELAY;
250 		if (bmread(dev, MIFCSR) & 8)
251 			val |= 1 << nb;
252 		bmwrite(dev, MIFCSR, 1);
253 		MIFDELAY;
254 	}
255 	bmwrite(dev, MIFCSR, 0);
256 	MIFDELAY;
257 	bmwrite(dev, MIFCSR, 1);
258 	MIFDELAY;
259 	return val;
260 }
261 
262 static void
263 bmac_mif_writebits(struct net_device *dev, unsigned int val, int nb)
264 {
265 	int b;
266 
267 	while (--nb >= 0) {
268 		b = (val & (1 << nb))? 6: 4;
269 		bmwrite(dev, MIFCSR, b);
270 		MIFDELAY;
271 		bmwrite(dev, MIFCSR, b|1);
272 		MIFDELAY;
273 	}
274 }
275 
276 static unsigned int
277 bmac_mif_read(struct net_device *dev, unsigned int addr)
278 {
279 	unsigned int val;
280 
281 	bmwrite(dev, MIFCSR, 4);
282 	MIFDELAY;
283 	bmac_mif_writebits(dev, ~0U, 32);
284 	bmac_mif_writebits(dev, 6, 4);
285 	bmac_mif_writebits(dev, addr, 10);
286 	bmwrite(dev, MIFCSR, 2);
287 	MIFDELAY;
288 	bmwrite(dev, MIFCSR, 1);
289 	MIFDELAY;
290 	val = bmac_mif_readbits(dev, 17);
291 	bmwrite(dev, MIFCSR, 4);
292 	MIFDELAY;
293 	return val;
294 }
295 
296 static void
297 bmac_mif_write(struct net_device *dev, unsigned int addr, unsigned int val)
298 {
299 	bmwrite(dev, MIFCSR, 4);
300 	MIFDELAY;
301 	bmac_mif_writebits(dev, ~0U, 32);
302 	bmac_mif_writebits(dev, 5, 4);
303 	bmac_mif_writebits(dev, addr, 10);
304 	bmac_mif_writebits(dev, 2, 2);
305 	bmac_mif_writebits(dev, val, 16);
306 	bmac_mif_writebits(dev, 3, 2);
307 }
308 
309 static void
310 bmac_init_registers(struct net_device *dev)
311 {
312 	struct bmac_data *bp = netdev_priv(dev);
313 	volatile unsigned short regValue;
314 	unsigned short *pWord16;
315 	int i;
316 
317 	/* XXDEBUG(("bmac: enter init_registers\n")); */
318 
319 	bmwrite(dev, RXRST, RxResetValue);
320 	bmwrite(dev, TXRST, TxResetBit);
321 
322 	i = 100;
323 	do {
324 		--i;
325 		udelay(10000);
326 		regValue = bmread(dev, TXRST); /* wait for reset to clear..acknowledge */
327 	} while ((regValue & TxResetBit) && i > 0);
328 
329 	if (!bp->is_bmac_plus) {
330 		regValue = bmread(dev, XCVRIF);
331 		regValue |= ClkBit | SerialMode | COLActiveLow;
332 		bmwrite(dev, XCVRIF, regValue);
333 		udelay(10000);
334 	}
335 
336 	bmwrite(dev, RSEED, (unsigned short)0x1968);
337 
338 	regValue = bmread(dev, XIFC);
339 	regValue |= TxOutputEnable;
340 	bmwrite(dev, XIFC, regValue);
341 
342 	bmread(dev, PAREG);
343 
344 	/* set collision counters to 0 */
345 	bmwrite(dev, NCCNT, 0);
346 	bmwrite(dev, NTCNT, 0);
347 	bmwrite(dev, EXCNT, 0);
348 	bmwrite(dev, LTCNT, 0);
349 
350 	/* set rx counters to 0 */
351 	bmwrite(dev, FRCNT, 0);
352 	bmwrite(dev, LECNT, 0);
353 	bmwrite(dev, AECNT, 0);
354 	bmwrite(dev, FECNT, 0);
355 	bmwrite(dev, RXCV, 0);
356 
357 	/* set tx fifo information */
358 	bmwrite(dev, TXTH, 4);	/* 4 octets before tx starts */
359 
360 	bmwrite(dev, TXFIFOCSR, 0);	/* first disable txFIFO */
361 	bmwrite(dev, TXFIFOCSR, TxFIFOEnable );
362 
363 	/* set rx fifo information */
364 	bmwrite(dev, RXFIFOCSR, 0);	/* first disable rxFIFO */
365 	bmwrite(dev, RXFIFOCSR, RxFIFOEnable );
366 
367 	//bmwrite(dev, TXCFG, TxMACEnable);	       	/* TxNeverGiveUp maybe later */
368 	bmread(dev, STATUS);		/* read it just to clear it */
369 
370 	/* zero out the chip Hash Filter registers */
371 	for (i=0; i<4; i++) bp->hash_table_mask[i] = 0;
372 	bmwrite(dev, BHASH3, bp->hash_table_mask[0]); 	/* bits 15 - 0 */
373 	bmwrite(dev, BHASH2, bp->hash_table_mask[1]); 	/* bits 31 - 16 */
374 	bmwrite(dev, BHASH1, bp->hash_table_mask[2]); 	/* bits 47 - 32 */
375 	bmwrite(dev, BHASH0, bp->hash_table_mask[3]); 	/* bits 63 - 48 */
376 
377 	pWord16 = (unsigned short *)dev->dev_addr;
378 	bmwrite(dev, MADD0, *pWord16++);
379 	bmwrite(dev, MADD1, *pWord16++);
380 	bmwrite(dev, MADD2, *pWord16);
381 
382 	bmwrite(dev, RXCFG, RxCRCNoStrip | RxHashFilterEnable | RxRejectOwnPackets);
383 
384 	bmwrite(dev, INTDISABLE, EnableNormal);
385 }
386 
387 #if 0
388 static void
389 bmac_disable_interrupts(struct net_device *dev)
390 {
391 	bmwrite(dev, INTDISABLE, DisableAll);
392 }
393 
394 static void
395 bmac_enable_interrupts(struct net_device *dev)
396 {
397 	bmwrite(dev, INTDISABLE, EnableNormal);
398 }
399 #endif
400 
401 
402 static void
403 bmac_start_chip(struct net_device *dev)
404 {
405 	struct bmac_data *bp = netdev_priv(dev);
406 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
407 	unsigned short	oldConfig;
408 
409 	/* enable rx dma channel */
410 	dbdma_continue(rd);
411 
412 	oldConfig = bmread(dev, TXCFG);
413 	bmwrite(dev, TXCFG, oldConfig | TxMACEnable );
414 
415 	/* turn on rx plus any other bits already on (promiscuous possibly) */
416 	oldConfig = bmread(dev, RXCFG);
417 	bmwrite(dev, RXCFG, oldConfig | RxMACEnable );
418 	udelay(20000);
419 }
420 
421 static void
422 bmac_init_phy(struct net_device *dev)
423 {
424 	unsigned int addr;
425 	struct bmac_data *bp = netdev_priv(dev);
426 
427 	printk(KERN_DEBUG "phy registers:");
428 	for (addr = 0; addr < 32; ++addr) {
429 		if ((addr & 7) == 0)
430 			printk(KERN_DEBUG);
431 		printk(KERN_CONT " %.4x", bmac_mif_read(dev, addr));
432 	}
433 	printk(KERN_CONT "\n");
434 
435 	if (bp->is_bmac_plus) {
436 		unsigned int capable, ctrl;
437 
438 		ctrl = bmac_mif_read(dev, 0);
439 		capable = ((bmac_mif_read(dev, 1) & 0xf800) >> 6) | 1;
440 		if (bmac_mif_read(dev, 4) != capable ||
441 		    (ctrl & 0x1000) == 0) {
442 			bmac_mif_write(dev, 4, capable);
443 			bmac_mif_write(dev, 0, 0x1200);
444 		} else
445 			bmac_mif_write(dev, 0, 0x1000);
446 	}
447 }
448 
449 static void bmac_init_chip(struct net_device *dev)
450 {
451 	bmac_init_phy(dev);
452 	bmac_init_registers(dev);
453 }
454 
455 #ifdef CONFIG_PM
456 static int bmac_suspend(struct macio_dev *mdev, pm_message_t state)
457 {
458 	struct net_device* dev = macio_get_drvdata(mdev);
459 	struct bmac_data *bp = netdev_priv(dev);
460 	unsigned long flags;
461 	unsigned short config;
462 	int i;
463 
464 	netif_device_detach(dev);
465 	/* prolly should wait for dma to finish & turn off the chip */
466 	spin_lock_irqsave(&bp->lock, flags);
467 	if (bp->timeout_active) {
468 		del_timer(&bp->tx_timeout);
469 		bp->timeout_active = 0;
470 	}
471 	disable_irq(dev->irq);
472 	disable_irq(bp->tx_dma_intr);
473 	disable_irq(bp->rx_dma_intr);
474 	bp->sleeping = 1;
475 	spin_unlock_irqrestore(&bp->lock, flags);
476 	if (bp->opened) {
477 		volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
478 		volatile struct dbdma_regs __iomem *td = bp->tx_dma;
479 
480 		config = bmread(dev, RXCFG);
481 		bmwrite(dev, RXCFG, (config & ~RxMACEnable));
482 		config = bmread(dev, TXCFG);
483        		bmwrite(dev, TXCFG, (config & ~TxMACEnable));
484 		bmwrite(dev, INTDISABLE, DisableAll); /* disable all intrs */
485        		/* disable rx and tx dma */
486 		rd->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
487 		td->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
488        		/* free some skb's */
489        		for (i=0; i<N_RX_RING; i++) {
490        			if (bp->rx_bufs[i] != NULL) {
491        				dev_kfree_skb(bp->rx_bufs[i]);
492        				bp->rx_bufs[i] = NULL;
493        			}
494        		}
495        		for (i = 0; i<N_TX_RING; i++) {
496 			if (bp->tx_bufs[i] != NULL) {
497 		       		dev_kfree_skb(bp->tx_bufs[i]);
498 	       			bp->tx_bufs[i] = NULL;
499 		       	}
500 		}
501 	}
502        	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
503 	return 0;
504 }
505 
506 static int bmac_resume(struct macio_dev *mdev)
507 {
508 	struct net_device* dev = macio_get_drvdata(mdev);
509 	struct bmac_data *bp = netdev_priv(dev);
510 
511 	/* see if this is enough */
512 	if (bp->opened)
513 		bmac_reset_and_enable(dev);
514 
515 	enable_irq(dev->irq);
516        	enable_irq(bp->tx_dma_intr);
517        	enable_irq(bp->rx_dma_intr);
518        	netif_device_attach(dev);
519 
520 	return 0;
521 }
522 #endif /* CONFIG_PM */
523 
524 static int bmac_set_address(struct net_device *dev, void *addr)
525 {
526 	struct bmac_data *bp = netdev_priv(dev);
527 	unsigned char *p = addr;
528 	unsigned short *pWord16;
529 	unsigned long flags;
530 	int i;
531 
532 	XXDEBUG(("bmac: enter set_address\n"));
533 	spin_lock_irqsave(&bp->lock, flags);
534 
535 	for (i = 0; i < 6; ++i) {
536 		dev->dev_addr[i] = p[i];
537 	}
538 	/* load up the hardware address */
539 	pWord16  = (unsigned short *)dev->dev_addr;
540 	bmwrite(dev, MADD0, *pWord16++);
541 	bmwrite(dev, MADD1, *pWord16++);
542 	bmwrite(dev, MADD2, *pWord16);
543 
544 	spin_unlock_irqrestore(&bp->lock, flags);
545 	XXDEBUG(("bmac: exit set_address\n"));
546 	return 0;
547 }
548 
549 static inline void bmac_set_timeout(struct net_device *dev)
550 {
551 	struct bmac_data *bp = netdev_priv(dev);
552 	unsigned long flags;
553 
554 	spin_lock_irqsave(&bp->lock, flags);
555 	if (bp->timeout_active)
556 		del_timer(&bp->tx_timeout);
557 	bp->tx_timeout.expires = jiffies + TX_TIMEOUT;
558 	add_timer(&bp->tx_timeout);
559 	bp->timeout_active = 1;
560 	spin_unlock_irqrestore(&bp->lock, flags);
561 }
562 
563 static void
564 bmac_construct_xmt(struct sk_buff *skb, volatile struct dbdma_cmd *cp)
565 {
566 	void *vaddr;
567 	unsigned long baddr;
568 	unsigned long len;
569 
570 	len = skb->len;
571 	vaddr = skb->data;
572 	baddr = virt_to_bus(vaddr);
573 
574 	dbdma_setcmd(cp, (OUTPUT_LAST | INTR_ALWAYS | WAIT_IFCLR), len, baddr, 0);
575 }
576 
577 static void
578 bmac_construct_rxbuff(struct sk_buff *skb, volatile struct dbdma_cmd *cp)
579 {
580 	unsigned char *addr = skb? skb->data: bmac_emergency_rxbuf;
581 
582 	dbdma_setcmd(cp, (INPUT_LAST | INTR_ALWAYS), RX_BUFLEN,
583 		     virt_to_bus(addr), 0);
584 }
585 
586 static void
587 bmac_init_tx_ring(struct bmac_data *bp)
588 {
589 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
590 
591 	memset((char *)bp->tx_cmds, 0, (N_TX_RING+1) * sizeof(struct dbdma_cmd));
592 
593 	bp->tx_empty = 0;
594 	bp->tx_fill = 0;
595 	bp->tx_fullup = 0;
596 
597 	/* put a branch at the end of the tx command list */
598 	dbdma_setcmd(&bp->tx_cmds[N_TX_RING],
599 		     (DBDMA_NOP | BR_ALWAYS), 0, 0, virt_to_bus(bp->tx_cmds));
600 
601 	/* reset tx dma */
602 	dbdma_reset(td);
603 	out_le32(&td->wait_sel, 0x00200020);
604 	out_le32(&td->cmdptr, virt_to_bus(bp->tx_cmds));
605 }
606 
607 static int
608 bmac_init_rx_ring(struct net_device *dev)
609 {
610 	struct bmac_data *bp = netdev_priv(dev);
611 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
612 	int i;
613 	struct sk_buff *skb;
614 
615 	/* initialize list of sk_buffs for receiving and set up recv dma */
616 	memset((char *)bp->rx_cmds, 0,
617 	       (N_RX_RING + 1) * sizeof(struct dbdma_cmd));
618 	for (i = 0; i < N_RX_RING; i++) {
619 		if ((skb = bp->rx_bufs[i]) == NULL) {
620 			bp->rx_bufs[i] = skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
621 			if (skb != NULL)
622 				skb_reserve(skb, 2);
623 		}
624 		bmac_construct_rxbuff(skb, &bp->rx_cmds[i]);
625 	}
626 
627 	bp->rx_empty = 0;
628 	bp->rx_fill = i;
629 
630 	/* Put a branch back to the beginning of the receive command list */
631 	dbdma_setcmd(&bp->rx_cmds[N_RX_RING],
632 		     (DBDMA_NOP | BR_ALWAYS), 0, 0, virt_to_bus(bp->rx_cmds));
633 
634 	/* start rx dma */
635 	dbdma_reset(rd);
636 	out_le32(&rd->cmdptr, virt_to_bus(bp->rx_cmds));
637 
638 	return 1;
639 }
640 
641 
642 static int bmac_transmit_packet(struct sk_buff *skb, struct net_device *dev)
643 {
644 	struct bmac_data *bp = netdev_priv(dev);
645 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
646 	int i;
647 
648 	/* see if there's a free slot in the tx ring */
649 	/* XXDEBUG(("bmac_xmit_start: empty=%d fill=%d\n", */
650 	/* 	     bp->tx_empty, bp->tx_fill)); */
651 	i = bp->tx_fill + 1;
652 	if (i >= N_TX_RING)
653 		i = 0;
654 	if (i == bp->tx_empty) {
655 		netif_stop_queue(dev);
656 		bp->tx_fullup = 1;
657 		XXDEBUG(("bmac_transmit_packet: tx ring full\n"));
658 		return -1;		/* can't take it at the moment */
659 	}
660 
661 	dbdma_setcmd(&bp->tx_cmds[i], DBDMA_STOP, 0, 0, 0);
662 
663 	bmac_construct_xmt(skb, &bp->tx_cmds[bp->tx_fill]);
664 
665 	bp->tx_bufs[bp->tx_fill] = skb;
666 	bp->tx_fill = i;
667 
668 	dev->stats.tx_bytes += skb->len;
669 
670 	dbdma_continue(td);
671 
672 	return 0;
673 }
674 
675 static int rxintcount;
676 
677 static irqreturn_t bmac_rxdma_intr(int irq, void *dev_id)
678 {
679 	struct net_device *dev = (struct net_device *) dev_id;
680 	struct bmac_data *bp = netdev_priv(dev);
681 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
682 	volatile struct dbdma_cmd *cp;
683 	int i, nb, stat;
684 	struct sk_buff *skb;
685 	unsigned int residual;
686 	int last;
687 	unsigned long flags;
688 
689 	spin_lock_irqsave(&bp->lock, flags);
690 
691 	if (++rxintcount < 10) {
692 		XXDEBUG(("bmac_rxdma_intr\n"));
693 	}
694 
695 	last = -1;
696 	i = bp->rx_empty;
697 
698 	while (1) {
699 		cp = &bp->rx_cmds[i];
700 		stat = le16_to_cpu(cp->xfer_status);
701 		residual = le16_to_cpu(cp->res_count);
702 		if ((stat & ACTIVE) == 0)
703 			break;
704 		nb = RX_BUFLEN - residual - 2;
705 		if (nb < (ETHERMINPACKET - ETHERCRC)) {
706 			skb = NULL;
707 			dev->stats.rx_length_errors++;
708 			dev->stats.rx_errors++;
709 		} else {
710 			skb = bp->rx_bufs[i];
711 			bp->rx_bufs[i] = NULL;
712 		}
713 		if (skb != NULL) {
714 			nb -= ETHERCRC;
715 			skb_put(skb, nb);
716 			skb->protocol = eth_type_trans(skb, dev);
717 			netif_rx(skb);
718 			++dev->stats.rx_packets;
719 			dev->stats.rx_bytes += nb;
720 		} else {
721 			++dev->stats.rx_dropped;
722 		}
723 		if ((skb = bp->rx_bufs[i]) == NULL) {
724 			bp->rx_bufs[i] = skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
725 			if (skb != NULL)
726 				skb_reserve(bp->rx_bufs[i], 2);
727 		}
728 		bmac_construct_rxbuff(skb, &bp->rx_cmds[i]);
729 		cp->res_count = cpu_to_le16(0);
730 		cp->xfer_status = cpu_to_le16(0);
731 		last = i;
732 		if (++i >= N_RX_RING) i = 0;
733 	}
734 
735 	if (last != -1) {
736 		bp->rx_fill = last;
737 		bp->rx_empty = i;
738 	}
739 
740 	dbdma_continue(rd);
741 	spin_unlock_irqrestore(&bp->lock, flags);
742 
743 	if (rxintcount < 10) {
744 		XXDEBUG(("bmac_rxdma_intr done\n"));
745 	}
746 	return IRQ_HANDLED;
747 }
748 
749 static int txintcount;
750 
751 static irqreturn_t bmac_txdma_intr(int irq, void *dev_id)
752 {
753 	struct net_device *dev = (struct net_device *) dev_id;
754 	struct bmac_data *bp = netdev_priv(dev);
755 	volatile struct dbdma_cmd *cp;
756 	int stat;
757 	unsigned long flags;
758 
759 	spin_lock_irqsave(&bp->lock, flags);
760 
761 	if (txintcount++ < 10) {
762 		XXDEBUG(("bmac_txdma_intr\n"));
763 	}
764 
765 	/*     del_timer(&bp->tx_timeout); */
766 	/*     bp->timeout_active = 0; */
767 
768 	while (1) {
769 		cp = &bp->tx_cmds[bp->tx_empty];
770 		stat = le16_to_cpu(cp->xfer_status);
771 		if (txintcount < 10) {
772 			XXDEBUG(("bmac_txdma_xfer_stat=%#0x\n", stat));
773 		}
774 		if (!(stat & ACTIVE)) {
775 			/*
776 			 * status field might not have been filled by DBDMA
777 			 */
778 			if (cp == bus_to_virt(in_le32(&bp->tx_dma->cmdptr)))
779 				break;
780 		}
781 
782 		if (bp->tx_bufs[bp->tx_empty]) {
783 			++dev->stats.tx_packets;
784 			dev_kfree_skb_irq(bp->tx_bufs[bp->tx_empty]);
785 		}
786 		bp->tx_bufs[bp->tx_empty] = NULL;
787 		bp->tx_fullup = 0;
788 		netif_wake_queue(dev);
789 		if (++bp->tx_empty >= N_TX_RING)
790 			bp->tx_empty = 0;
791 		if (bp->tx_empty == bp->tx_fill)
792 			break;
793 	}
794 
795 	spin_unlock_irqrestore(&bp->lock, flags);
796 
797 	if (txintcount < 10) {
798 		XXDEBUG(("bmac_txdma_intr done->bmac_start\n"));
799 	}
800 
801 	bmac_start(dev);
802 	return IRQ_HANDLED;
803 }
804 
805 #ifndef SUNHME_MULTICAST
806 /* Real fast bit-reversal algorithm, 6-bit values */
807 static int reverse6[64] = {
808 	0x0,0x20,0x10,0x30,0x8,0x28,0x18,0x38,
809 	0x4,0x24,0x14,0x34,0xc,0x2c,0x1c,0x3c,
810 	0x2,0x22,0x12,0x32,0xa,0x2a,0x1a,0x3a,
811 	0x6,0x26,0x16,0x36,0xe,0x2e,0x1e,0x3e,
812 	0x1,0x21,0x11,0x31,0x9,0x29,0x19,0x39,
813 	0x5,0x25,0x15,0x35,0xd,0x2d,0x1d,0x3d,
814 	0x3,0x23,0x13,0x33,0xb,0x2b,0x1b,0x3b,
815 	0x7,0x27,0x17,0x37,0xf,0x2f,0x1f,0x3f
816 };
817 
818 static unsigned int
819 crc416(unsigned int curval, unsigned short nxtval)
820 {
821 	register unsigned int counter, cur = curval, next = nxtval;
822 	register int high_crc_set, low_data_set;
823 
824 	/* Swap bytes */
825 	next = ((next & 0x00FF) << 8) | (next >> 8);
826 
827 	/* Compute bit-by-bit */
828 	for (counter = 0; counter < 16; ++counter) {
829 		/* is high CRC bit set? */
830 		if ((cur & 0x80000000) == 0) high_crc_set = 0;
831 		else high_crc_set = 1;
832 
833 		cur = cur << 1;
834 
835 		if ((next & 0x0001) == 0) low_data_set = 0;
836 		else low_data_set = 1;
837 
838 		next = next >> 1;
839 
840 		/* do the XOR */
841 		if (high_crc_set ^ low_data_set) cur = cur ^ ENET_CRCPOLY;
842 	}
843 	return cur;
844 }
845 
846 static unsigned int
847 bmac_crc(unsigned short *address)
848 {
849 	unsigned int newcrc;
850 
851 	XXDEBUG(("bmac_crc: addr=%#04x, %#04x, %#04x\n", *address, address[1], address[2]));
852 	newcrc = crc416(0xffffffff, *address);	/* address bits 47 - 32 */
853 	newcrc = crc416(newcrc, address[1]);	/* address bits 31 - 16 */
854 	newcrc = crc416(newcrc, address[2]);	/* address bits 15 - 0  */
855 
856 	return(newcrc);
857 }
858 
859 /*
860  * Add requested mcast addr to BMac's hash table filter.
861  *
862  */
863 
864 static void
865 bmac_addhash(struct bmac_data *bp, unsigned char *addr)
866 {
867 	unsigned int	 crc;
868 	unsigned short	 mask;
869 
870 	if (!(*addr)) return;
871 	crc = bmac_crc((unsigned short *)addr) & 0x3f; /* Big-endian alert! */
872 	crc = reverse6[crc];	/* Hyperfast bit-reversing algorithm */
873 	if (bp->hash_use_count[crc]++) return; /* This bit is already set */
874 	mask = crc % 16;
875 	mask = (unsigned char)1 << mask;
876 	bp->hash_use_count[crc/16] |= mask;
877 }
878 
879 static void
880 bmac_removehash(struct bmac_data *bp, unsigned char *addr)
881 {
882 	unsigned int crc;
883 	unsigned char mask;
884 
885 	/* Now, delete the address from the filter copy, as indicated */
886 	crc = bmac_crc((unsigned short *)addr) & 0x3f; /* Big-endian alert! */
887 	crc = reverse6[crc];	/* Hyperfast bit-reversing algorithm */
888 	if (bp->hash_use_count[crc] == 0) return; /* That bit wasn't in use! */
889 	if (--bp->hash_use_count[crc]) return; /* That bit is still in use */
890 	mask = crc % 16;
891 	mask = ((unsigned char)1 << mask) ^ 0xffff; /* To turn off bit */
892 	bp->hash_table_mask[crc/16] &= mask;
893 }
894 
895 /*
896  * Sync the adapter with the software copy of the multicast mask
897  *  (logical address filter).
898  */
899 
900 static void
901 bmac_rx_off(struct net_device *dev)
902 {
903 	unsigned short rx_cfg;
904 
905 	rx_cfg = bmread(dev, RXCFG);
906 	rx_cfg &= ~RxMACEnable;
907 	bmwrite(dev, RXCFG, rx_cfg);
908 	do {
909 		rx_cfg = bmread(dev, RXCFG);
910 	}  while (rx_cfg & RxMACEnable);
911 }
912 
913 unsigned short
914 bmac_rx_on(struct net_device *dev, int hash_enable, int promisc_enable)
915 {
916 	unsigned short rx_cfg;
917 
918 	rx_cfg = bmread(dev, RXCFG);
919 	rx_cfg |= RxMACEnable;
920 	if (hash_enable) rx_cfg |= RxHashFilterEnable;
921 	else rx_cfg &= ~RxHashFilterEnable;
922 	if (promisc_enable) rx_cfg |= RxPromiscEnable;
923 	else rx_cfg &= ~RxPromiscEnable;
924 	bmwrite(dev, RXRST, RxResetValue);
925 	bmwrite(dev, RXFIFOCSR, 0);	/* first disable rxFIFO */
926 	bmwrite(dev, RXFIFOCSR, RxFIFOEnable );
927 	bmwrite(dev, RXCFG, rx_cfg );
928 	return rx_cfg;
929 }
930 
931 static void
932 bmac_update_hash_table_mask(struct net_device *dev, struct bmac_data *bp)
933 {
934 	bmwrite(dev, BHASH3, bp->hash_table_mask[0]); /* bits 15 - 0 */
935 	bmwrite(dev, BHASH2, bp->hash_table_mask[1]); /* bits 31 - 16 */
936 	bmwrite(dev, BHASH1, bp->hash_table_mask[2]); /* bits 47 - 32 */
937 	bmwrite(dev, BHASH0, bp->hash_table_mask[3]); /* bits 63 - 48 */
938 }
939 
940 #if 0
941 static void
942 bmac_add_multi(struct net_device *dev,
943 	       struct bmac_data *bp, unsigned char *addr)
944 {
945 	/* XXDEBUG(("bmac: enter bmac_add_multi\n")); */
946 	bmac_addhash(bp, addr);
947 	bmac_rx_off(dev);
948 	bmac_update_hash_table_mask(dev, bp);
949 	bmac_rx_on(dev, 1, (dev->flags & IFF_PROMISC)? 1 : 0);
950 	/* XXDEBUG(("bmac: exit bmac_add_multi\n")); */
951 }
952 
953 static void
954 bmac_remove_multi(struct net_device *dev,
955 		  struct bmac_data *bp, unsigned char *addr)
956 {
957 	bmac_removehash(bp, addr);
958 	bmac_rx_off(dev);
959 	bmac_update_hash_table_mask(dev, bp);
960 	bmac_rx_on(dev, 1, (dev->flags & IFF_PROMISC)? 1 : 0);
961 }
962 #endif
963 
964 /* Set or clear the multicast filter for this adaptor.
965     num_addrs == -1	Promiscuous mode, receive all packets
966     num_addrs == 0	Normal mode, clear multicast list
967     num_addrs > 0	Multicast mode, receive normal and MC packets, and do
968 			best-effort filtering.
969  */
970 static void bmac_set_multicast(struct net_device *dev)
971 {
972 	struct netdev_hw_addr *ha;
973 	struct bmac_data *bp = netdev_priv(dev);
974 	int num_addrs = netdev_mc_count(dev);
975 	unsigned short rx_cfg;
976 	int i;
977 
978 	if (bp->sleeping)
979 		return;
980 
981 	XXDEBUG(("bmac: enter bmac_set_multicast, n_addrs=%d\n", num_addrs));
982 
983 	if((dev->flags & IFF_ALLMULTI) || (netdev_mc_count(dev) > 64)) {
984 		for (i=0; i<4; i++) bp->hash_table_mask[i] = 0xffff;
985 		bmac_update_hash_table_mask(dev, bp);
986 		rx_cfg = bmac_rx_on(dev, 1, 0);
987 		XXDEBUG(("bmac: all multi, rx_cfg=%#08x\n"));
988 	} else if ((dev->flags & IFF_PROMISC) || (num_addrs < 0)) {
989 		rx_cfg = bmread(dev, RXCFG);
990 		rx_cfg |= RxPromiscEnable;
991 		bmwrite(dev, RXCFG, rx_cfg);
992 		rx_cfg = bmac_rx_on(dev, 0, 1);
993 		XXDEBUG(("bmac: promisc mode enabled, rx_cfg=%#08x\n", rx_cfg));
994 	} else {
995 		for (i=0; i<4; i++) bp->hash_table_mask[i] = 0;
996 		for (i=0; i<64; i++) bp->hash_use_count[i] = 0;
997 		if (num_addrs == 0) {
998 			rx_cfg = bmac_rx_on(dev, 0, 0);
999 			XXDEBUG(("bmac: multi disabled, rx_cfg=%#08x\n", rx_cfg));
1000 		} else {
1001 			netdev_for_each_mc_addr(ha, dev)
1002 				bmac_addhash(bp, ha->addr);
1003 			bmac_update_hash_table_mask(dev, bp);
1004 			rx_cfg = bmac_rx_on(dev, 1, 0);
1005 			XXDEBUG(("bmac: multi enabled, rx_cfg=%#08x\n", rx_cfg));
1006 		}
1007 	}
1008 	/* XXDEBUG(("bmac: exit bmac_set_multicast\n")); */
1009 }
1010 #else /* ifdef SUNHME_MULTICAST */
1011 
1012 /* The version of set_multicast below was lifted from sunhme.c */
1013 
1014 static void bmac_set_multicast(struct net_device *dev)
1015 {
1016 	struct netdev_hw_addr *ha;
1017 	unsigned short rx_cfg;
1018 	u32 crc;
1019 
1020 	if((dev->flags & IFF_ALLMULTI) || (netdev_mc_count(dev) > 64)) {
1021 		bmwrite(dev, BHASH0, 0xffff);
1022 		bmwrite(dev, BHASH1, 0xffff);
1023 		bmwrite(dev, BHASH2, 0xffff);
1024 		bmwrite(dev, BHASH3, 0xffff);
1025 	} else if(dev->flags & IFF_PROMISC) {
1026 		rx_cfg = bmread(dev, RXCFG);
1027 		rx_cfg |= RxPromiscEnable;
1028 		bmwrite(dev, RXCFG, rx_cfg);
1029 	} else {
1030 		u16 hash_table[4] = { 0 };
1031 
1032 		rx_cfg = bmread(dev, RXCFG);
1033 		rx_cfg &= ~RxPromiscEnable;
1034 		bmwrite(dev, RXCFG, rx_cfg);
1035 
1036 		netdev_for_each_mc_addr(ha, dev) {
1037 			crc = ether_crc_le(6, ha->addr);
1038 			crc >>= 26;
1039 			hash_table[crc >> 4] |= 1 << (crc & 0xf);
1040 		}
1041 		bmwrite(dev, BHASH0, hash_table[0]);
1042 		bmwrite(dev, BHASH1, hash_table[1]);
1043 		bmwrite(dev, BHASH2, hash_table[2]);
1044 		bmwrite(dev, BHASH3, hash_table[3]);
1045 	}
1046 }
1047 #endif /* SUNHME_MULTICAST */
1048 
1049 static int miscintcount;
1050 
1051 static irqreturn_t bmac_misc_intr(int irq, void *dev_id)
1052 {
1053 	struct net_device *dev = (struct net_device *) dev_id;
1054 	unsigned int status = bmread(dev, STATUS);
1055 	if (miscintcount++ < 10) {
1056 		XXDEBUG(("bmac_misc_intr\n"));
1057 	}
1058 	/* XXDEBUG(("bmac_misc_intr, status=%#08x\n", status)); */
1059 	/*     bmac_txdma_intr_inner(irq, dev_id); */
1060 	/*   if (status & FrameReceived) dev->stats.rx_dropped++; */
1061 	if (status & RxErrorMask) dev->stats.rx_errors++;
1062 	if (status & RxCRCCntExp) dev->stats.rx_crc_errors++;
1063 	if (status & RxLenCntExp) dev->stats.rx_length_errors++;
1064 	if (status & RxOverFlow) dev->stats.rx_over_errors++;
1065 	if (status & RxAlignCntExp) dev->stats.rx_frame_errors++;
1066 
1067 	/*   if (status & FrameSent) dev->stats.tx_dropped++; */
1068 	if (status & TxErrorMask) dev->stats.tx_errors++;
1069 	if (status & TxUnderrun) dev->stats.tx_fifo_errors++;
1070 	if (status & TxNormalCollExp) dev->stats.collisions++;
1071 	return IRQ_HANDLED;
1072 }
1073 
1074 /*
1075  * Procedure for reading EEPROM
1076  */
1077 #define SROMAddressLength	5
1078 #define DataInOn		0x0008
1079 #define DataInOff		0x0000
1080 #define Clk			0x0002
1081 #define ChipSelect		0x0001
1082 #define SDIShiftCount		3
1083 #define SD0ShiftCount		2
1084 #define	DelayValue		1000	/* number of microseconds */
1085 #define SROMStartOffset		10	/* this is in words */
1086 #define SROMReadCount		3	/* number of words to read from SROM */
1087 #define SROMAddressBits		6
1088 #define EnetAddressOffset	20
1089 
1090 static unsigned char
1091 bmac_clock_out_bit(struct net_device *dev)
1092 {
1093 	unsigned short         data;
1094 	unsigned short         val;
1095 
1096 	bmwrite(dev, SROMCSR, ChipSelect | Clk);
1097 	udelay(DelayValue);
1098 
1099 	data = bmread(dev, SROMCSR);
1100 	udelay(DelayValue);
1101 	val = (data >> SD0ShiftCount) & 1;
1102 
1103 	bmwrite(dev, SROMCSR, ChipSelect);
1104 	udelay(DelayValue);
1105 
1106 	return val;
1107 }
1108 
1109 static void
1110 bmac_clock_in_bit(struct net_device *dev, unsigned int val)
1111 {
1112 	unsigned short data;
1113 
1114 	if (val != 0 && val != 1) return;
1115 
1116 	data = (val << SDIShiftCount);
1117 	bmwrite(dev, SROMCSR, data | ChipSelect  );
1118 	udelay(DelayValue);
1119 
1120 	bmwrite(dev, SROMCSR, data | ChipSelect | Clk );
1121 	udelay(DelayValue);
1122 
1123 	bmwrite(dev, SROMCSR, data | ChipSelect);
1124 	udelay(DelayValue);
1125 }
1126 
1127 static void
1128 reset_and_select_srom(struct net_device *dev)
1129 {
1130 	/* first reset */
1131 	bmwrite(dev, SROMCSR, 0);
1132 	udelay(DelayValue);
1133 
1134 	/* send it the read command (110) */
1135 	bmac_clock_in_bit(dev, 1);
1136 	bmac_clock_in_bit(dev, 1);
1137 	bmac_clock_in_bit(dev, 0);
1138 }
1139 
1140 static unsigned short
1141 read_srom(struct net_device *dev, unsigned int addr, unsigned int addr_len)
1142 {
1143 	unsigned short data, val;
1144 	int i;
1145 
1146 	/* send out the address we want to read from */
1147 	for (i = 0; i < addr_len; i++)	{
1148 		val = addr >> (addr_len-i-1);
1149 		bmac_clock_in_bit(dev, val & 1);
1150 	}
1151 
1152 	/* Now read in the 16-bit data */
1153 	data = 0;
1154 	for (i = 0; i < 16; i++)	{
1155 		val = bmac_clock_out_bit(dev);
1156 		data <<= 1;
1157 		data |= val;
1158 	}
1159 	bmwrite(dev, SROMCSR, 0);
1160 
1161 	return data;
1162 }
1163 
1164 /*
1165  * It looks like Cogent and SMC use different methods for calculating
1166  * checksums. What a pain..
1167  */
1168 
1169 static int
1170 bmac_verify_checksum(struct net_device *dev)
1171 {
1172 	unsigned short data, storedCS;
1173 
1174 	reset_and_select_srom(dev);
1175 	data = read_srom(dev, 3, SROMAddressBits);
1176 	storedCS = ((data >> 8) & 0x0ff) | ((data << 8) & 0xff00);
1177 
1178 	return 0;
1179 }
1180 
1181 
1182 static void
1183 bmac_get_station_address(struct net_device *dev, unsigned char *ea)
1184 {
1185 	int i;
1186 	unsigned short data;
1187 
1188 	for (i = 0; i < 6; i++)
1189 		{
1190 			reset_and_select_srom(dev);
1191 			data = read_srom(dev, i + EnetAddressOffset/2, SROMAddressBits);
1192 			ea[2*i]   = bitrev8(data & 0x0ff);
1193 			ea[2*i+1] = bitrev8((data >> 8) & 0x0ff);
1194 		}
1195 }
1196 
1197 static void bmac_reset_and_enable(struct net_device *dev)
1198 {
1199 	struct bmac_data *bp = netdev_priv(dev);
1200 	unsigned long flags;
1201 	struct sk_buff *skb;
1202 	unsigned char *data;
1203 
1204 	spin_lock_irqsave(&bp->lock, flags);
1205 	bmac_enable_and_reset_chip(dev);
1206 	bmac_init_tx_ring(bp);
1207 	bmac_init_rx_ring(dev);
1208 	bmac_init_chip(dev);
1209 	bmac_start_chip(dev);
1210 	bmwrite(dev, INTDISABLE, EnableNormal);
1211 	bp->sleeping = 0;
1212 
1213 	/*
1214 	 * It seems that the bmac can't receive until it's transmitted
1215 	 * a packet.  So we give it a dummy packet to transmit.
1216 	 */
1217 	skb = netdev_alloc_skb(dev, ETHERMINPACKET);
1218 	if (skb != NULL) {
1219 		data = skb_put_zero(skb, ETHERMINPACKET);
1220 		memcpy(data, dev->dev_addr, ETH_ALEN);
1221 		memcpy(data + ETH_ALEN, dev->dev_addr, ETH_ALEN);
1222 		bmac_transmit_packet(skb, dev);
1223 	}
1224 	spin_unlock_irqrestore(&bp->lock, flags);
1225 }
1226 
1227 static const struct ethtool_ops bmac_ethtool_ops = {
1228 	.get_link		= ethtool_op_get_link,
1229 };
1230 
1231 static const struct net_device_ops bmac_netdev_ops = {
1232 	.ndo_open		= bmac_open,
1233 	.ndo_stop		= bmac_close,
1234 	.ndo_start_xmit		= bmac_output,
1235 	.ndo_set_rx_mode	= bmac_set_multicast,
1236 	.ndo_set_mac_address	= bmac_set_address,
1237 	.ndo_validate_addr	= eth_validate_addr,
1238 };
1239 
1240 static int bmac_probe(struct macio_dev *mdev, const struct of_device_id *match)
1241 {
1242 	int j, rev, ret;
1243 	struct bmac_data *bp;
1244 	const unsigned char *prop_addr;
1245 	unsigned char addr[6];
1246 	struct net_device *dev;
1247 	int is_bmac_plus = ((int)match->data) != 0;
1248 
1249 	if (macio_resource_count(mdev) != 3 || macio_irq_count(mdev) != 3) {
1250 		printk(KERN_ERR "BMAC: can't use, need 3 addrs and 3 intrs\n");
1251 		return -ENODEV;
1252 	}
1253 	prop_addr = of_get_property(macio_get_of_node(mdev),
1254 			"mac-address", NULL);
1255 	if (prop_addr == NULL) {
1256 		prop_addr = of_get_property(macio_get_of_node(mdev),
1257 				"local-mac-address", NULL);
1258 		if (prop_addr == NULL) {
1259 			printk(KERN_ERR "BMAC: Can't get mac-address\n");
1260 			return -ENODEV;
1261 		}
1262 	}
1263 	memcpy(addr, prop_addr, sizeof(addr));
1264 
1265 	dev = alloc_etherdev(PRIV_BYTES);
1266 	if (!dev)
1267 		return -ENOMEM;
1268 
1269 	bp = netdev_priv(dev);
1270 	SET_NETDEV_DEV(dev, &mdev->ofdev.dev);
1271 	macio_set_drvdata(mdev, dev);
1272 
1273 	bp->mdev = mdev;
1274 	spin_lock_init(&bp->lock);
1275 
1276 	if (macio_request_resources(mdev, "bmac")) {
1277 		printk(KERN_ERR "BMAC: can't request IO resource !\n");
1278 		goto out_free;
1279 	}
1280 
1281 	dev->base_addr = (unsigned long)
1282 		ioremap(macio_resource_start(mdev, 0), macio_resource_len(mdev, 0));
1283 	if (dev->base_addr == 0)
1284 		goto out_release;
1285 
1286 	dev->irq = macio_irq(mdev, 0);
1287 
1288 	bmac_enable_and_reset_chip(dev);
1289 	bmwrite(dev, INTDISABLE, DisableAll);
1290 
1291 	rev = addr[0] == 0 && addr[1] == 0xA0;
1292 	for (j = 0; j < 6; ++j)
1293 		dev->dev_addr[j] = rev ? bitrev8(addr[j]): addr[j];
1294 
1295 	/* Enable chip without interrupts for now */
1296 	bmac_enable_and_reset_chip(dev);
1297 	bmwrite(dev, INTDISABLE, DisableAll);
1298 
1299 	dev->netdev_ops = &bmac_netdev_ops;
1300 	dev->ethtool_ops = &bmac_ethtool_ops;
1301 
1302 	bmac_get_station_address(dev, addr);
1303 	if (bmac_verify_checksum(dev) != 0)
1304 		goto err_out_iounmap;
1305 
1306 	bp->is_bmac_plus = is_bmac_plus;
1307 	bp->tx_dma = ioremap(macio_resource_start(mdev, 1), macio_resource_len(mdev, 1));
1308 	if (!bp->tx_dma)
1309 		goto err_out_iounmap;
1310 	bp->tx_dma_intr = macio_irq(mdev, 1);
1311 	bp->rx_dma = ioremap(macio_resource_start(mdev, 2), macio_resource_len(mdev, 2));
1312 	if (!bp->rx_dma)
1313 		goto err_out_iounmap_tx;
1314 	bp->rx_dma_intr = macio_irq(mdev, 2);
1315 
1316 	bp->tx_cmds = (volatile struct dbdma_cmd *) DBDMA_ALIGN(bp + 1);
1317 	bp->rx_cmds = bp->tx_cmds + N_TX_RING + 1;
1318 
1319 	bp->queue = (struct sk_buff_head *)(bp->rx_cmds + N_RX_RING + 1);
1320 	skb_queue_head_init(bp->queue);
1321 
1322 	timer_setup(&bp->tx_timeout, bmac_tx_timeout, 0);
1323 
1324 	ret = request_irq(dev->irq, bmac_misc_intr, 0, "BMAC-misc", dev);
1325 	if (ret) {
1326 		printk(KERN_ERR "BMAC: can't get irq %d\n", dev->irq);
1327 		goto err_out_iounmap_rx;
1328 	}
1329 	ret = request_irq(bp->tx_dma_intr, bmac_txdma_intr, 0, "BMAC-txdma", dev);
1330 	if (ret) {
1331 		printk(KERN_ERR "BMAC: can't get irq %d\n", bp->tx_dma_intr);
1332 		goto err_out_irq0;
1333 	}
1334 	ret = request_irq(bp->rx_dma_intr, bmac_rxdma_intr, 0, "BMAC-rxdma", dev);
1335 	if (ret) {
1336 		printk(KERN_ERR "BMAC: can't get irq %d\n", bp->rx_dma_intr);
1337 		goto err_out_irq1;
1338 	}
1339 
1340 	/* Mask chip interrupts and disable chip, will be
1341 	 * re-enabled on open()
1342 	 */
1343 	disable_irq(dev->irq);
1344 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
1345 
1346 	if (register_netdev(dev) != 0) {
1347 		printk(KERN_ERR "BMAC: Ethernet registration failed\n");
1348 		goto err_out_irq2;
1349 	}
1350 
1351 	printk(KERN_INFO "%s: BMAC%s at %pM",
1352 	       dev->name, (is_bmac_plus ? "+" : ""), dev->dev_addr);
1353 	XXDEBUG((", base_addr=%#0lx", dev->base_addr));
1354 	printk("\n");
1355 
1356 	return 0;
1357 
1358 err_out_irq2:
1359 	free_irq(bp->rx_dma_intr, dev);
1360 err_out_irq1:
1361 	free_irq(bp->tx_dma_intr, dev);
1362 err_out_irq0:
1363 	free_irq(dev->irq, dev);
1364 err_out_iounmap_rx:
1365 	iounmap(bp->rx_dma);
1366 err_out_iounmap_tx:
1367 	iounmap(bp->tx_dma);
1368 err_out_iounmap:
1369 	iounmap((void __iomem *)dev->base_addr);
1370 out_release:
1371 	macio_release_resources(mdev);
1372 out_free:
1373 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
1374 	free_netdev(dev);
1375 
1376 	return -ENODEV;
1377 }
1378 
1379 static int bmac_open(struct net_device *dev)
1380 {
1381 	struct bmac_data *bp = netdev_priv(dev);
1382 	/* XXDEBUG(("bmac: enter open\n")); */
1383 	/* reset the chip */
1384 	bp->opened = 1;
1385 	bmac_reset_and_enable(dev);
1386 	enable_irq(dev->irq);
1387 	return 0;
1388 }
1389 
1390 static int bmac_close(struct net_device *dev)
1391 {
1392 	struct bmac_data *bp = netdev_priv(dev);
1393 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
1394 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
1395 	unsigned short config;
1396 	int i;
1397 
1398 	bp->sleeping = 1;
1399 
1400 	/* disable rx and tx */
1401 	config = bmread(dev, RXCFG);
1402 	bmwrite(dev, RXCFG, (config & ~RxMACEnable));
1403 
1404 	config = bmread(dev, TXCFG);
1405 	bmwrite(dev, TXCFG, (config & ~TxMACEnable));
1406 
1407 	bmwrite(dev, INTDISABLE, DisableAll); /* disable all intrs */
1408 
1409 	/* disable rx and tx dma */
1410 	rd->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
1411 	td->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
1412 
1413 	/* free some skb's */
1414 	XXDEBUG(("bmac: free rx bufs\n"));
1415 	for (i=0; i<N_RX_RING; i++) {
1416 		if (bp->rx_bufs[i] != NULL) {
1417 			dev_kfree_skb(bp->rx_bufs[i]);
1418 			bp->rx_bufs[i] = NULL;
1419 		}
1420 	}
1421 	XXDEBUG(("bmac: free tx bufs\n"));
1422 	for (i = 0; i<N_TX_RING; i++) {
1423 		if (bp->tx_bufs[i] != NULL) {
1424 			dev_kfree_skb(bp->tx_bufs[i]);
1425 			bp->tx_bufs[i] = NULL;
1426 		}
1427 	}
1428 	XXDEBUG(("bmac: all bufs freed\n"));
1429 
1430 	bp->opened = 0;
1431 	disable_irq(dev->irq);
1432 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
1433 
1434 	return 0;
1435 }
1436 
1437 static void
1438 bmac_start(struct net_device *dev)
1439 {
1440 	struct bmac_data *bp = netdev_priv(dev);
1441 	int i;
1442 	struct sk_buff *skb;
1443 	unsigned long flags;
1444 
1445 	if (bp->sleeping)
1446 		return;
1447 
1448 	spin_lock_irqsave(&bp->lock, flags);
1449 	while (1) {
1450 		i = bp->tx_fill + 1;
1451 		if (i >= N_TX_RING)
1452 			i = 0;
1453 		if (i == bp->tx_empty)
1454 			break;
1455 		skb = skb_dequeue(bp->queue);
1456 		if (skb == NULL)
1457 			break;
1458 		bmac_transmit_packet(skb, dev);
1459 	}
1460 	spin_unlock_irqrestore(&bp->lock, flags);
1461 }
1462 
1463 static int
1464 bmac_output(struct sk_buff *skb, struct net_device *dev)
1465 {
1466 	struct bmac_data *bp = netdev_priv(dev);
1467 	skb_queue_tail(bp->queue, skb);
1468 	bmac_start(dev);
1469 	return NETDEV_TX_OK;
1470 }
1471 
1472 static void bmac_tx_timeout(struct timer_list *t)
1473 {
1474 	struct bmac_data *bp = from_timer(bp, t, tx_timeout);
1475 	struct net_device *dev = macio_get_drvdata(bp->mdev);
1476 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
1477 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
1478 	volatile struct dbdma_cmd *cp;
1479 	unsigned long flags;
1480 	unsigned short config, oldConfig;
1481 	int i;
1482 
1483 	XXDEBUG(("bmac: tx_timeout called\n"));
1484 	spin_lock_irqsave(&bp->lock, flags);
1485 	bp->timeout_active = 0;
1486 
1487 	/* update various counters */
1488 /*     	bmac_handle_misc_intrs(bp, 0); */
1489 
1490 	cp = &bp->tx_cmds[bp->tx_empty];
1491 /*	XXDEBUG((KERN_DEBUG "bmac: tx dmastat=%x %x runt=%d pr=%x fs=%x fc=%x\n", */
1492 /* 	   le32_to_cpu(td->status), le16_to_cpu(cp->xfer_status), bp->tx_bad_runt, */
1493 /* 	   mb->pr, mb->xmtfs, mb->fifofc)); */
1494 
1495 	/* turn off both tx and rx and reset the chip */
1496 	config = bmread(dev, RXCFG);
1497 	bmwrite(dev, RXCFG, (config & ~RxMACEnable));
1498 	config = bmread(dev, TXCFG);
1499 	bmwrite(dev, TXCFG, (config & ~TxMACEnable));
1500 	out_le32(&td->control, DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE|ACTIVE|DEAD));
1501 	printk(KERN_ERR "bmac: transmit timeout - resetting\n");
1502 	bmac_enable_and_reset_chip(dev);
1503 
1504 	/* restart rx dma */
1505 	cp = bus_to_virt(le32_to_cpu(rd->cmdptr));
1506 	out_le32(&rd->control, DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE|ACTIVE|DEAD));
1507 	out_le16(&cp->xfer_status, 0);
1508 	out_le32(&rd->cmdptr, virt_to_bus(cp));
1509 	out_le32(&rd->control, DBDMA_SET(RUN|WAKE));
1510 
1511 	/* fix up the transmit side */
1512 	XXDEBUG((KERN_DEBUG "bmac: tx empty=%d fill=%d fullup=%d\n",
1513 		 bp->tx_empty, bp->tx_fill, bp->tx_fullup));
1514 	i = bp->tx_empty;
1515 	++dev->stats.tx_errors;
1516 	if (i != bp->tx_fill) {
1517 		dev_kfree_skb(bp->tx_bufs[i]);
1518 		bp->tx_bufs[i] = NULL;
1519 		if (++i >= N_TX_RING) i = 0;
1520 		bp->tx_empty = i;
1521 	}
1522 	bp->tx_fullup = 0;
1523 	netif_wake_queue(dev);
1524 	if (i != bp->tx_fill) {
1525 		cp = &bp->tx_cmds[i];
1526 		out_le16(&cp->xfer_status, 0);
1527 		out_le16(&cp->command, OUTPUT_LAST);
1528 		out_le32(&td->cmdptr, virt_to_bus(cp));
1529 		out_le32(&td->control, DBDMA_SET(RUN));
1530 		/* 	bmac_set_timeout(dev); */
1531 		XXDEBUG((KERN_DEBUG "bmac: starting %d\n", i));
1532 	}
1533 
1534 	/* turn it back on */
1535 	oldConfig = bmread(dev, RXCFG);
1536 	bmwrite(dev, RXCFG, oldConfig | RxMACEnable );
1537 	oldConfig = bmread(dev, TXCFG);
1538 	bmwrite(dev, TXCFG, oldConfig | TxMACEnable );
1539 
1540 	spin_unlock_irqrestore(&bp->lock, flags);
1541 }
1542 
1543 #if 0
1544 static void dump_dbdma(volatile struct dbdma_cmd *cp,int count)
1545 {
1546 	int i,*ip;
1547 
1548 	for (i=0;i< count;i++) {
1549 		ip = (int*)(cp+i);
1550 
1551 		printk("dbdma req 0x%x addr 0x%x baddr 0x%x xfer/res 0x%x\n",
1552 		       le32_to_cpup(ip+0),
1553 		       le32_to_cpup(ip+1),
1554 		       le32_to_cpup(ip+2),
1555 		       le32_to_cpup(ip+3));
1556 	}
1557 
1558 }
1559 #endif
1560 
1561 #if 0
1562 static int
1563 bmac_proc_info(char *buffer, char **start, off_t offset, int length)
1564 {
1565 	int len = 0;
1566 	off_t pos   = 0;
1567 	off_t begin = 0;
1568 	int i;
1569 
1570 	if (bmac_devs == NULL)
1571 		return -ENOSYS;
1572 
1573 	len += sprintf(buffer, "BMAC counters & registers\n");
1574 
1575 	for (i = 0; i<N_REG_ENTRIES; i++) {
1576 		len += sprintf(buffer + len, "%s: %#08x\n",
1577 			       reg_entries[i].name,
1578 			       bmread(bmac_devs, reg_entries[i].reg_offset));
1579 		pos = begin + len;
1580 
1581 		if (pos < offset) {
1582 			len = 0;
1583 			begin = pos;
1584 		}
1585 
1586 		if (pos > offset+length) break;
1587 	}
1588 
1589 	*start = buffer + (offset - begin);
1590 	len -= (offset - begin);
1591 
1592 	if (len > length) len = length;
1593 
1594 	return len;
1595 }
1596 #endif
1597 
1598 static int bmac_remove(struct macio_dev *mdev)
1599 {
1600 	struct net_device *dev = macio_get_drvdata(mdev);
1601 	struct bmac_data *bp = netdev_priv(dev);
1602 
1603 	unregister_netdev(dev);
1604 
1605        	free_irq(dev->irq, dev);
1606 	free_irq(bp->tx_dma_intr, dev);
1607 	free_irq(bp->rx_dma_intr, dev);
1608 
1609 	iounmap((void __iomem *)dev->base_addr);
1610 	iounmap(bp->tx_dma);
1611 	iounmap(bp->rx_dma);
1612 
1613 	macio_release_resources(mdev);
1614 
1615 	free_netdev(dev);
1616 
1617 	return 0;
1618 }
1619 
1620 static const struct of_device_id bmac_match[] =
1621 {
1622 	{
1623 	.name 		= "bmac",
1624 	.data		= (void *)0,
1625 	},
1626 	{
1627 	.type		= "network",
1628 	.compatible	= "bmac+",
1629 	.data		= (void *)1,
1630 	},
1631 	{},
1632 };
1633 MODULE_DEVICE_TABLE (of, bmac_match);
1634 
1635 static struct macio_driver bmac_driver =
1636 {
1637 	.driver = {
1638 		.name 		= "bmac",
1639 		.owner		= THIS_MODULE,
1640 		.of_match_table	= bmac_match,
1641 	},
1642 	.probe		= bmac_probe,
1643 	.remove		= bmac_remove,
1644 #ifdef CONFIG_PM
1645 	.suspend	= bmac_suspend,
1646 	.resume		= bmac_resume,
1647 #endif
1648 };
1649 
1650 
1651 static int __init bmac_init(void)
1652 {
1653 	if (bmac_emergency_rxbuf == NULL) {
1654 		bmac_emergency_rxbuf = kmalloc(RX_BUFLEN, GFP_KERNEL);
1655 		if (bmac_emergency_rxbuf == NULL)
1656 			return -ENOMEM;
1657 	}
1658 
1659 	return macio_register_driver(&bmac_driver);
1660 }
1661 
1662 static void __exit bmac_exit(void)
1663 {
1664 	macio_unregister_driver(&bmac_driver);
1665 
1666 	kfree(bmac_emergency_rxbuf);
1667 	bmac_emergency_rxbuf = NULL;
1668 }
1669 
1670 MODULE_AUTHOR("Randy Gobbel/Paul Mackerras");
1671 MODULE_DESCRIPTION("PowerMac BMAC ethernet driver.");
1672 MODULE_LICENSE("GPL");
1673 
1674 module_init(bmac_init);
1675 module_exit(bmac_exit);
1676