xref: /openbmc/linux/drivers/net/ethernet/apple/bmac.c (revision 22d55f02)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Network device driver for the BMAC ethernet controller on
4  * Apple Powermacs.  Assumes it's under a DBDMA controller.
5  *
6  * Copyright (C) 1998 Randy Gobbel.
7  *
8  * May 1999, Al Viro: proper release of /proc/net/bmac entry, switched to
9  * dynamic procfs inode.
10  */
11 #include <linux/interrupt.h>
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/netdevice.h>
15 #include <linux/etherdevice.h>
16 #include <linux/delay.h>
17 #include <linux/string.h>
18 #include <linux/timer.h>
19 #include <linux/proc_fs.h>
20 #include <linux/init.h>
21 #include <linux/spinlock.h>
22 #include <linux/crc32.h>
23 #include <linux/crc32poly.h>
24 #include <linux/bitrev.h>
25 #include <linux/ethtool.h>
26 #include <linux/slab.h>
27 #include <asm/prom.h>
28 #include <asm/dbdma.h>
29 #include <asm/io.h>
30 #include <asm/page.h>
31 #include <asm/pgtable.h>
32 #include <asm/machdep.h>
33 #include <asm/pmac_feature.h>
34 #include <asm/macio.h>
35 #include <asm/irq.h>
36 
37 #include "bmac.h"
38 
39 #define trunc_page(x)	((void *)(((unsigned long)(x)) & ~((unsigned long)(PAGE_SIZE - 1))))
40 #define round_page(x)	trunc_page(((unsigned long)(x)) + ((unsigned long)(PAGE_SIZE - 1)))
41 
42 /* switch to use multicast code lifted from sunhme driver */
43 #define SUNHME_MULTICAST
44 
45 #define N_RX_RING	64
46 #define N_TX_RING	32
47 #define MAX_TX_ACTIVE	1
48 #define ETHERCRC	4
49 #define ETHERMINPACKET	64
50 #define ETHERMTU	1500
51 #define RX_BUFLEN	(ETHERMTU + 14 + ETHERCRC + 2)
52 #define TX_TIMEOUT	HZ	/* 1 second */
53 
54 /* Bits in transmit DMA status */
55 #define TX_DMA_ERR	0x80
56 
57 #define XXDEBUG(args)
58 
59 struct bmac_data {
60 	/* volatile struct bmac *bmac; */
61 	struct sk_buff_head *queue;
62 	volatile struct dbdma_regs __iomem *tx_dma;
63 	int tx_dma_intr;
64 	volatile struct dbdma_regs __iomem *rx_dma;
65 	int rx_dma_intr;
66 	volatile struct dbdma_cmd *tx_cmds;	/* xmit dma command list */
67 	volatile struct dbdma_cmd *rx_cmds;	/* recv dma command list */
68 	struct macio_dev *mdev;
69 	int is_bmac_plus;
70 	struct sk_buff *rx_bufs[N_RX_RING];
71 	int rx_fill;
72 	int rx_empty;
73 	struct sk_buff *tx_bufs[N_TX_RING];
74 	int tx_fill;
75 	int tx_empty;
76 	unsigned char tx_fullup;
77 	struct timer_list tx_timeout;
78 	int timeout_active;
79 	int sleeping;
80 	int opened;
81 	unsigned short hash_use_count[64];
82 	unsigned short hash_table_mask[4];
83 	spinlock_t lock;
84 };
85 
86 #if 0 /* Move that to ethtool */
87 
88 typedef struct bmac_reg_entry {
89 	char *name;
90 	unsigned short reg_offset;
91 } bmac_reg_entry_t;
92 
93 #define N_REG_ENTRIES 31
94 
95 static bmac_reg_entry_t reg_entries[N_REG_ENTRIES] = {
96 	{"MEMADD", MEMADD},
97 	{"MEMDATAHI", MEMDATAHI},
98 	{"MEMDATALO", MEMDATALO},
99 	{"TXPNTR", TXPNTR},
100 	{"RXPNTR", RXPNTR},
101 	{"IPG1", IPG1},
102 	{"IPG2", IPG2},
103 	{"ALIMIT", ALIMIT},
104 	{"SLOT", SLOT},
105 	{"PALEN", PALEN},
106 	{"PAPAT", PAPAT},
107 	{"TXSFD", TXSFD},
108 	{"JAM", JAM},
109 	{"TXCFG", TXCFG},
110 	{"TXMAX", TXMAX},
111 	{"TXMIN", TXMIN},
112 	{"PAREG", PAREG},
113 	{"DCNT", DCNT},
114 	{"NCCNT", NCCNT},
115 	{"NTCNT", NTCNT},
116 	{"EXCNT", EXCNT},
117 	{"LTCNT", LTCNT},
118 	{"TXSM", TXSM},
119 	{"RXCFG", RXCFG},
120 	{"RXMAX", RXMAX},
121 	{"RXMIN", RXMIN},
122 	{"FRCNT", FRCNT},
123 	{"AECNT", AECNT},
124 	{"FECNT", FECNT},
125 	{"RXSM", RXSM},
126 	{"RXCV", RXCV}
127 };
128 
129 #endif
130 
131 static unsigned char *bmac_emergency_rxbuf;
132 
133 /*
134  * Number of bytes of private data per BMAC: allow enough for
135  * the rx and tx dma commands plus a branch dma command each,
136  * and another 16 bytes to allow us to align the dma command
137  * buffers on a 16 byte boundary.
138  */
139 #define PRIV_BYTES	(sizeof(struct bmac_data) \
140 	+ (N_RX_RING + N_TX_RING + 4) * sizeof(struct dbdma_cmd) \
141 	+ sizeof(struct sk_buff_head))
142 
143 static int bmac_open(struct net_device *dev);
144 static int bmac_close(struct net_device *dev);
145 static int bmac_transmit_packet(struct sk_buff *skb, struct net_device *dev);
146 static void bmac_set_multicast(struct net_device *dev);
147 static void bmac_reset_and_enable(struct net_device *dev);
148 static void bmac_start_chip(struct net_device *dev);
149 static void bmac_init_chip(struct net_device *dev);
150 static void bmac_init_registers(struct net_device *dev);
151 static void bmac_enable_and_reset_chip(struct net_device *dev);
152 static int bmac_set_address(struct net_device *dev, void *addr);
153 static irqreturn_t bmac_misc_intr(int irq, void *dev_id);
154 static irqreturn_t bmac_txdma_intr(int irq, void *dev_id);
155 static irqreturn_t bmac_rxdma_intr(int irq, void *dev_id);
156 static void bmac_set_timeout(struct net_device *dev);
157 static void bmac_tx_timeout(struct timer_list *t);
158 static netdev_tx_t bmac_output(struct sk_buff *skb, struct net_device *dev);
159 static void bmac_start(struct net_device *dev);
160 
161 #define	DBDMA_SET(x)	( ((x) | (x) << 16) )
162 #define	DBDMA_CLEAR(x)	( (x) << 16)
163 
164 static inline void
165 dbdma_st32(volatile __u32 __iomem *a, unsigned long x)
166 {
167 	__asm__ volatile( "stwbrx %0,0,%1" : : "r" (x), "r" (a) : "memory");
168 }
169 
170 static inline unsigned long
171 dbdma_ld32(volatile __u32 __iomem *a)
172 {
173 	__u32 swap;
174 	__asm__ volatile ("lwbrx %0,0,%1" :  "=r" (swap) : "r" (a));
175 	return swap;
176 }
177 
178 static void
179 dbdma_continue(volatile struct dbdma_regs __iomem *dmap)
180 {
181 	dbdma_st32(&dmap->control,
182 		   DBDMA_SET(RUN|WAKE) | DBDMA_CLEAR(PAUSE|DEAD));
183 	eieio();
184 }
185 
186 static void
187 dbdma_reset(volatile struct dbdma_regs __iomem *dmap)
188 {
189 	dbdma_st32(&dmap->control,
190 		   DBDMA_CLEAR(ACTIVE|DEAD|WAKE|FLUSH|PAUSE|RUN));
191 	eieio();
192 	while (dbdma_ld32(&dmap->status) & RUN)
193 		eieio();
194 }
195 
196 static void
197 dbdma_setcmd(volatile struct dbdma_cmd *cp,
198 	     unsigned short cmd, unsigned count, unsigned long addr,
199 	     unsigned long cmd_dep)
200 {
201 	out_le16(&cp->command, cmd);
202 	out_le16(&cp->req_count, count);
203 	out_le32(&cp->phy_addr, addr);
204 	out_le32(&cp->cmd_dep, cmd_dep);
205 	out_le16(&cp->xfer_status, 0);
206 	out_le16(&cp->res_count, 0);
207 }
208 
209 static inline
210 void bmwrite(struct net_device *dev, unsigned long reg_offset, unsigned data )
211 {
212 	out_le16((void __iomem *)dev->base_addr + reg_offset, data);
213 }
214 
215 
216 static inline
217 unsigned short bmread(struct net_device *dev, unsigned long reg_offset )
218 {
219 	return in_le16((void __iomem *)dev->base_addr + reg_offset);
220 }
221 
222 static void
223 bmac_enable_and_reset_chip(struct net_device *dev)
224 {
225 	struct bmac_data *bp = netdev_priv(dev);
226 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
227 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
228 
229 	if (rd)
230 		dbdma_reset(rd);
231 	if (td)
232 		dbdma_reset(td);
233 
234 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 1);
235 }
236 
237 #define MIFDELAY	udelay(10)
238 
239 static unsigned int
240 bmac_mif_readbits(struct net_device *dev, int nb)
241 {
242 	unsigned int val = 0;
243 
244 	while (--nb >= 0) {
245 		bmwrite(dev, MIFCSR, 0);
246 		MIFDELAY;
247 		if (bmread(dev, MIFCSR) & 8)
248 			val |= 1 << nb;
249 		bmwrite(dev, MIFCSR, 1);
250 		MIFDELAY;
251 	}
252 	bmwrite(dev, MIFCSR, 0);
253 	MIFDELAY;
254 	bmwrite(dev, MIFCSR, 1);
255 	MIFDELAY;
256 	return val;
257 }
258 
259 static void
260 bmac_mif_writebits(struct net_device *dev, unsigned int val, int nb)
261 {
262 	int b;
263 
264 	while (--nb >= 0) {
265 		b = (val & (1 << nb))? 6: 4;
266 		bmwrite(dev, MIFCSR, b);
267 		MIFDELAY;
268 		bmwrite(dev, MIFCSR, b|1);
269 		MIFDELAY;
270 	}
271 }
272 
273 static unsigned int
274 bmac_mif_read(struct net_device *dev, unsigned int addr)
275 {
276 	unsigned int val;
277 
278 	bmwrite(dev, MIFCSR, 4);
279 	MIFDELAY;
280 	bmac_mif_writebits(dev, ~0U, 32);
281 	bmac_mif_writebits(dev, 6, 4);
282 	bmac_mif_writebits(dev, addr, 10);
283 	bmwrite(dev, MIFCSR, 2);
284 	MIFDELAY;
285 	bmwrite(dev, MIFCSR, 1);
286 	MIFDELAY;
287 	val = bmac_mif_readbits(dev, 17);
288 	bmwrite(dev, MIFCSR, 4);
289 	MIFDELAY;
290 	return val;
291 }
292 
293 static void
294 bmac_mif_write(struct net_device *dev, unsigned int addr, unsigned int val)
295 {
296 	bmwrite(dev, MIFCSR, 4);
297 	MIFDELAY;
298 	bmac_mif_writebits(dev, ~0U, 32);
299 	bmac_mif_writebits(dev, 5, 4);
300 	bmac_mif_writebits(dev, addr, 10);
301 	bmac_mif_writebits(dev, 2, 2);
302 	bmac_mif_writebits(dev, val, 16);
303 	bmac_mif_writebits(dev, 3, 2);
304 }
305 
306 static void
307 bmac_init_registers(struct net_device *dev)
308 {
309 	struct bmac_data *bp = netdev_priv(dev);
310 	volatile unsigned short regValue;
311 	unsigned short *pWord16;
312 	int i;
313 
314 	/* XXDEBUG(("bmac: enter init_registers\n")); */
315 
316 	bmwrite(dev, RXRST, RxResetValue);
317 	bmwrite(dev, TXRST, TxResetBit);
318 
319 	i = 100;
320 	do {
321 		--i;
322 		udelay(10000);
323 		regValue = bmread(dev, TXRST); /* wait for reset to clear..acknowledge */
324 	} while ((regValue & TxResetBit) && i > 0);
325 
326 	if (!bp->is_bmac_plus) {
327 		regValue = bmread(dev, XCVRIF);
328 		regValue |= ClkBit | SerialMode | COLActiveLow;
329 		bmwrite(dev, XCVRIF, regValue);
330 		udelay(10000);
331 	}
332 
333 	bmwrite(dev, RSEED, (unsigned short)0x1968);
334 
335 	regValue = bmread(dev, XIFC);
336 	regValue |= TxOutputEnable;
337 	bmwrite(dev, XIFC, regValue);
338 
339 	bmread(dev, PAREG);
340 
341 	/* set collision counters to 0 */
342 	bmwrite(dev, NCCNT, 0);
343 	bmwrite(dev, NTCNT, 0);
344 	bmwrite(dev, EXCNT, 0);
345 	bmwrite(dev, LTCNT, 0);
346 
347 	/* set rx counters to 0 */
348 	bmwrite(dev, FRCNT, 0);
349 	bmwrite(dev, LECNT, 0);
350 	bmwrite(dev, AECNT, 0);
351 	bmwrite(dev, FECNT, 0);
352 	bmwrite(dev, RXCV, 0);
353 
354 	/* set tx fifo information */
355 	bmwrite(dev, TXTH, 4);	/* 4 octets before tx starts */
356 
357 	bmwrite(dev, TXFIFOCSR, 0);	/* first disable txFIFO */
358 	bmwrite(dev, TXFIFOCSR, TxFIFOEnable );
359 
360 	/* set rx fifo information */
361 	bmwrite(dev, RXFIFOCSR, 0);	/* first disable rxFIFO */
362 	bmwrite(dev, RXFIFOCSR, RxFIFOEnable );
363 
364 	//bmwrite(dev, TXCFG, TxMACEnable);	       	/* TxNeverGiveUp maybe later */
365 	bmread(dev, STATUS);		/* read it just to clear it */
366 
367 	/* zero out the chip Hash Filter registers */
368 	for (i=0; i<4; i++) bp->hash_table_mask[i] = 0;
369 	bmwrite(dev, BHASH3, bp->hash_table_mask[0]); 	/* bits 15 - 0 */
370 	bmwrite(dev, BHASH2, bp->hash_table_mask[1]); 	/* bits 31 - 16 */
371 	bmwrite(dev, BHASH1, bp->hash_table_mask[2]); 	/* bits 47 - 32 */
372 	bmwrite(dev, BHASH0, bp->hash_table_mask[3]); 	/* bits 63 - 48 */
373 
374 	pWord16 = (unsigned short *)dev->dev_addr;
375 	bmwrite(dev, MADD0, *pWord16++);
376 	bmwrite(dev, MADD1, *pWord16++);
377 	bmwrite(dev, MADD2, *pWord16);
378 
379 	bmwrite(dev, RXCFG, RxCRCNoStrip | RxHashFilterEnable | RxRejectOwnPackets);
380 
381 	bmwrite(dev, INTDISABLE, EnableNormal);
382 }
383 
384 #if 0
385 static void
386 bmac_disable_interrupts(struct net_device *dev)
387 {
388 	bmwrite(dev, INTDISABLE, DisableAll);
389 }
390 
391 static void
392 bmac_enable_interrupts(struct net_device *dev)
393 {
394 	bmwrite(dev, INTDISABLE, EnableNormal);
395 }
396 #endif
397 
398 
399 static void
400 bmac_start_chip(struct net_device *dev)
401 {
402 	struct bmac_data *bp = netdev_priv(dev);
403 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
404 	unsigned short	oldConfig;
405 
406 	/* enable rx dma channel */
407 	dbdma_continue(rd);
408 
409 	oldConfig = bmread(dev, TXCFG);
410 	bmwrite(dev, TXCFG, oldConfig | TxMACEnable );
411 
412 	/* turn on rx plus any other bits already on (promiscuous possibly) */
413 	oldConfig = bmread(dev, RXCFG);
414 	bmwrite(dev, RXCFG, oldConfig | RxMACEnable );
415 	udelay(20000);
416 }
417 
418 static void
419 bmac_init_phy(struct net_device *dev)
420 {
421 	unsigned int addr;
422 	struct bmac_data *bp = netdev_priv(dev);
423 
424 	printk(KERN_DEBUG "phy registers:");
425 	for (addr = 0; addr < 32; ++addr) {
426 		if ((addr & 7) == 0)
427 			printk(KERN_DEBUG);
428 		printk(KERN_CONT " %.4x", bmac_mif_read(dev, addr));
429 	}
430 	printk(KERN_CONT "\n");
431 
432 	if (bp->is_bmac_plus) {
433 		unsigned int capable, ctrl;
434 
435 		ctrl = bmac_mif_read(dev, 0);
436 		capable = ((bmac_mif_read(dev, 1) & 0xf800) >> 6) | 1;
437 		if (bmac_mif_read(dev, 4) != capable ||
438 		    (ctrl & 0x1000) == 0) {
439 			bmac_mif_write(dev, 4, capable);
440 			bmac_mif_write(dev, 0, 0x1200);
441 		} else
442 			bmac_mif_write(dev, 0, 0x1000);
443 	}
444 }
445 
446 static void bmac_init_chip(struct net_device *dev)
447 {
448 	bmac_init_phy(dev);
449 	bmac_init_registers(dev);
450 }
451 
452 #ifdef CONFIG_PM
453 static int bmac_suspend(struct macio_dev *mdev, pm_message_t state)
454 {
455 	struct net_device* dev = macio_get_drvdata(mdev);
456 	struct bmac_data *bp = netdev_priv(dev);
457 	unsigned long flags;
458 	unsigned short config;
459 	int i;
460 
461 	netif_device_detach(dev);
462 	/* prolly should wait for dma to finish & turn off the chip */
463 	spin_lock_irqsave(&bp->lock, flags);
464 	if (bp->timeout_active) {
465 		del_timer(&bp->tx_timeout);
466 		bp->timeout_active = 0;
467 	}
468 	disable_irq(dev->irq);
469 	disable_irq(bp->tx_dma_intr);
470 	disable_irq(bp->rx_dma_intr);
471 	bp->sleeping = 1;
472 	spin_unlock_irqrestore(&bp->lock, flags);
473 	if (bp->opened) {
474 		volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
475 		volatile struct dbdma_regs __iomem *td = bp->tx_dma;
476 
477 		config = bmread(dev, RXCFG);
478 		bmwrite(dev, RXCFG, (config & ~RxMACEnable));
479 		config = bmread(dev, TXCFG);
480        		bmwrite(dev, TXCFG, (config & ~TxMACEnable));
481 		bmwrite(dev, INTDISABLE, DisableAll); /* disable all intrs */
482        		/* disable rx and tx dma */
483 		rd->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
484 		td->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
485        		/* free some skb's */
486        		for (i=0; i<N_RX_RING; i++) {
487        			if (bp->rx_bufs[i] != NULL) {
488        				dev_kfree_skb(bp->rx_bufs[i]);
489        				bp->rx_bufs[i] = NULL;
490        			}
491        		}
492        		for (i = 0; i<N_TX_RING; i++) {
493 			if (bp->tx_bufs[i] != NULL) {
494 		       		dev_kfree_skb(bp->tx_bufs[i]);
495 	       			bp->tx_bufs[i] = NULL;
496 		       	}
497 		}
498 	}
499        	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
500 	return 0;
501 }
502 
503 static int bmac_resume(struct macio_dev *mdev)
504 {
505 	struct net_device* dev = macio_get_drvdata(mdev);
506 	struct bmac_data *bp = netdev_priv(dev);
507 
508 	/* see if this is enough */
509 	if (bp->opened)
510 		bmac_reset_and_enable(dev);
511 
512 	enable_irq(dev->irq);
513        	enable_irq(bp->tx_dma_intr);
514        	enable_irq(bp->rx_dma_intr);
515        	netif_device_attach(dev);
516 
517 	return 0;
518 }
519 #endif /* CONFIG_PM */
520 
521 static int bmac_set_address(struct net_device *dev, void *addr)
522 {
523 	struct bmac_data *bp = netdev_priv(dev);
524 	unsigned char *p = addr;
525 	unsigned short *pWord16;
526 	unsigned long flags;
527 	int i;
528 
529 	XXDEBUG(("bmac: enter set_address\n"));
530 	spin_lock_irqsave(&bp->lock, flags);
531 
532 	for (i = 0; i < 6; ++i) {
533 		dev->dev_addr[i] = p[i];
534 	}
535 	/* load up the hardware address */
536 	pWord16  = (unsigned short *)dev->dev_addr;
537 	bmwrite(dev, MADD0, *pWord16++);
538 	bmwrite(dev, MADD1, *pWord16++);
539 	bmwrite(dev, MADD2, *pWord16);
540 
541 	spin_unlock_irqrestore(&bp->lock, flags);
542 	XXDEBUG(("bmac: exit set_address\n"));
543 	return 0;
544 }
545 
546 static inline void bmac_set_timeout(struct net_device *dev)
547 {
548 	struct bmac_data *bp = netdev_priv(dev);
549 	unsigned long flags;
550 
551 	spin_lock_irqsave(&bp->lock, flags);
552 	if (bp->timeout_active)
553 		del_timer(&bp->tx_timeout);
554 	bp->tx_timeout.expires = jiffies + TX_TIMEOUT;
555 	add_timer(&bp->tx_timeout);
556 	bp->timeout_active = 1;
557 	spin_unlock_irqrestore(&bp->lock, flags);
558 }
559 
560 static void
561 bmac_construct_xmt(struct sk_buff *skb, volatile struct dbdma_cmd *cp)
562 {
563 	void *vaddr;
564 	unsigned long baddr;
565 	unsigned long len;
566 
567 	len = skb->len;
568 	vaddr = skb->data;
569 	baddr = virt_to_bus(vaddr);
570 
571 	dbdma_setcmd(cp, (OUTPUT_LAST | INTR_ALWAYS | WAIT_IFCLR), len, baddr, 0);
572 }
573 
574 static void
575 bmac_construct_rxbuff(struct sk_buff *skb, volatile struct dbdma_cmd *cp)
576 {
577 	unsigned char *addr = skb? skb->data: bmac_emergency_rxbuf;
578 
579 	dbdma_setcmd(cp, (INPUT_LAST | INTR_ALWAYS), RX_BUFLEN,
580 		     virt_to_bus(addr), 0);
581 }
582 
583 static void
584 bmac_init_tx_ring(struct bmac_data *bp)
585 {
586 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
587 
588 	memset((char *)bp->tx_cmds, 0, (N_TX_RING+1) * sizeof(struct dbdma_cmd));
589 
590 	bp->tx_empty = 0;
591 	bp->tx_fill = 0;
592 	bp->tx_fullup = 0;
593 
594 	/* put a branch at the end of the tx command list */
595 	dbdma_setcmd(&bp->tx_cmds[N_TX_RING],
596 		     (DBDMA_NOP | BR_ALWAYS), 0, 0, virt_to_bus(bp->tx_cmds));
597 
598 	/* reset tx dma */
599 	dbdma_reset(td);
600 	out_le32(&td->wait_sel, 0x00200020);
601 	out_le32(&td->cmdptr, virt_to_bus(bp->tx_cmds));
602 }
603 
604 static int
605 bmac_init_rx_ring(struct net_device *dev)
606 {
607 	struct bmac_data *bp = netdev_priv(dev);
608 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
609 	int i;
610 	struct sk_buff *skb;
611 
612 	/* initialize list of sk_buffs for receiving and set up recv dma */
613 	memset((char *)bp->rx_cmds, 0,
614 	       (N_RX_RING + 1) * sizeof(struct dbdma_cmd));
615 	for (i = 0; i < N_RX_RING; i++) {
616 		if ((skb = bp->rx_bufs[i]) == NULL) {
617 			bp->rx_bufs[i] = skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
618 			if (skb != NULL)
619 				skb_reserve(skb, 2);
620 		}
621 		bmac_construct_rxbuff(skb, &bp->rx_cmds[i]);
622 	}
623 
624 	bp->rx_empty = 0;
625 	bp->rx_fill = i;
626 
627 	/* Put a branch back to the beginning of the receive command list */
628 	dbdma_setcmd(&bp->rx_cmds[N_RX_RING],
629 		     (DBDMA_NOP | BR_ALWAYS), 0, 0, virt_to_bus(bp->rx_cmds));
630 
631 	/* start rx dma */
632 	dbdma_reset(rd);
633 	out_le32(&rd->cmdptr, virt_to_bus(bp->rx_cmds));
634 
635 	return 1;
636 }
637 
638 
639 static int bmac_transmit_packet(struct sk_buff *skb, struct net_device *dev)
640 {
641 	struct bmac_data *bp = netdev_priv(dev);
642 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
643 	int i;
644 
645 	/* see if there's a free slot in the tx ring */
646 	/* XXDEBUG(("bmac_xmit_start: empty=%d fill=%d\n", */
647 	/* 	     bp->tx_empty, bp->tx_fill)); */
648 	i = bp->tx_fill + 1;
649 	if (i >= N_TX_RING)
650 		i = 0;
651 	if (i == bp->tx_empty) {
652 		netif_stop_queue(dev);
653 		bp->tx_fullup = 1;
654 		XXDEBUG(("bmac_transmit_packet: tx ring full\n"));
655 		return -1;		/* can't take it at the moment */
656 	}
657 
658 	dbdma_setcmd(&bp->tx_cmds[i], DBDMA_STOP, 0, 0, 0);
659 
660 	bmac_construct_xmt(skb, &bp->tx_cmds[bp->tx_fill]);
661 
662 	bp->tx_bufs[bp->tx_fill] = skb;
663 	bp->tx_fill = i;
664 
665 	dev->stats.tx_bytes += skb->len;
666 
667 	dbdma_continue(td);
668 
669 	return 0;
670 }
671 
672 static int rxintcount;
673 
674 static irqreturn_t bmac_rxdma_intr(int irq, void *dev_id)
675 {
676 	struct net_device *dev = (struct net_device *) dev_id;
677 	struct bmac_data *bp = netdev_priv(dev);
678 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
679 	volatile struct dbdma_cmd *cp;
680 	int i, nb, stat;
681 	struct sk_buff *skb;
682 	unsigned int residual;
683 	int last;
684 	unsigned long flags;
685 
686 	spin_lock_irqsave(&bp->lock, flags);
687 
688 	if (++rxintcount < 10) {
689 		XXDEBUG(("bmac_rxdma_intr\n"));
690 	}
691 
692 	last = -1;
693 	i = bp->rx_empty;
694 
695 	while (1) {
696 		cp = &bp->rx_cmds[i];
697 		stat = le16_to_cpu(cp->xfer_status);
698 		residual = le16_to_cpu(cp->res_count);
699 		if ((stat & ACTIVE) == 0)
700 			break;
701 		nb = RX_BUFLEN - residual - 2;
702 		if (nb < (ETHERMINPACKET - ETHERCRC)) {
703 			skb = NULL;
704 			dev->stats.rx_length_errors++;
705 			dev->stats.rx_errors++;
706 		} else {
707 			skb = bp->rx_bufs[i];
708 			bp->rx_bufs[i] = NULL;
709 		}
710 		if (skb != NULL) {
711 			nb -= ETHERCRC;
712 			skb_put(skb, nb);
713 			skb->protocol = eth_type_trans(skb, dev);
714 			netif_rx(skb);
715 			++dev->stats.rx_packets;
716 			dev->stats.rx_bytes += nb;
717 		} else {
718 			++dev->stats.rx_dropped;
719 		}
720 		if ((skb = bp->rx_bufs[i]) == NULL) {
721 			bp->rx_bufs[i] = skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
722 			if (skb != NULL)
723 				skb_reserve(bp->rx_bufs[i], 2);
724 		}
725 		bmac_construct_rxbuff(skb, &bp->rx_cmds[i]);
726 		cp->res_count = cpu_to_le16(0);
727 		cp->xfer_status = cpu_to_le16(0);
728 		last = i;
729 		if (++i >= N_RX_RING) i = 0;
730 	}
731 
732 	if (last != -1) {
733 		bp->rx_fill = last;
734 		bp->rx_empty = i;
735 	}
736 
737 	dbdma_continue(rd);
738 	spin_unlock_irqrestore(&bp->lock, flags);
739 
740 	if (rxintcount < 10) {
741 		XXDEBUG(("bmac_rxdma_intr done\n"));
742 	}
743 	return IRQ_HANDLED;
744 }
745 
746 static int txintcount;
747 
748 static irqreturn_t bmac_txdma_intr(int irq, void *dev_id)
749 {
750 	struct net_device *dev = (struct net_device *) dev_id;
751 	struct bmac_data *bp = netdev_priv(dev);
752 	volatile struct dbdma_cmd *cp;
753 	int stat;
754 	unsigned long flags;
755 
756 	spin_lock_irqsave(&bp->lock, flags);
757 
758 	if (txintcount++ < 10) {
759 		XXDEBUG(("bmac_txdma_intr\n"));
760 	}
761 
762 	/*     del_timer(&bp->tx_timeout); */
763 	/*     bp->timeout_active = 0; */
764 
765 	while (1) {
766 		cp = &bp->tx_cmds[bp->tx_empty];
767 		stat = le16_to_cpu(cp->xfer_status);
768 		if (txintcount < 10) {
769 			XXDEBUG(("bmac_txdma_xfer_stat=%#0x\n", stat));
770 		}
771 		if (!(stat & ACTIVE)) {
772 			/*
773 			 * status field might not have been filled by DBDMA
774 			 */
775 			if (cp == bus_to_virt(in_le32(&bp->tx_dma->cmdptr)))
776 				break;
777 		}
778 
779 		if (bp->tx_bufs[bp->tx_empty]) {
780 			++dev->stats.tx_packets;
781 			dev_consume_skb_irq(bp->tx_bufs[bp->tx_empty]);
782 		}
783 		bp->tx_bufs[bp->tx_empty] = NULL;
784 		bp->tx_fullup = 0;
785 		netif_wake_queue(dev);
786 		if (++bp->tx_empty >= N_TX_RING)
787 			bp->tx_empty = 0;
788 		if (bp->tx_empty == bp->tx_fill)
789 			break;
790 	}
791 
792 	spin_unlock_irqrestore(&bp->lock, flags);
793 
794 	if (txintcount < 10) {
795 		XXDEBUG(("bmac_txdma_intr done->bmac_start\n"));
796 	}
797 
798 	bmac_start(dev);
799 	return IRQ_HANDLED;
800 }
801 
802 #ifndef SUNHME_MULTICAST
803 /* Real fast bit-reversal algorithm, 6-bit values */
804 static int reverse6[64] = {
805 	0x0,0x20,0x10,0x30,0x8,0x28,0x18,0x38,
806 	0x4,0x24,0x14,0x34,0xc,0x2c,0x1c,0x3c,
807 	0x2,0x22,0x12,0x32,0xa,0x2a,0x1a,0x3a,
808 	0x6,0x26,0x16,0x36,0xe,0x2e,0x1e,0x3e,
809 	0x1,0x21,0x11,0x31,0x9,0x29,0x19,0x39,
810 	0x5,0x25,0x15,0x35,0xd,0x2d,0x1d,0x3d,
811 	0x3,0x23,0x13,0x33,0xb,0x2b,0x1b,0x3b,
812 	0x7,0x27,0x17,0x37,0xf,0x2f,0x1f,0x3f
813 };
814 
815 static unsigned int
816 crc416(unsigned int curval, unsigned short nxtval)
817 {
818 	register unsigned int counter, cur = curval, next = nxtval;
819 	register int high_crc_set, low_data_set;
820 
821 	/* Swap bytes */
822 	next = ((next & 0x00FF) << 8) | (next >> 8);
823 
824 	/* Compute bit-by-bit */
825 	for (counter = 0; counter < 16; ++counter) {
826 		/* is high CRC bit set? */
827 		if ((cur & 0x80000000) == 0) high_crc_set = 0;
828 		else high_crc_set = 1;
829 
830 		cur = cur << 1;
831 
832 		if ((next & 0x0001) == 0) low_data_set = 0;
833 		else low_data_set = 1;
834 
835 		next = next >> 1;
836 
837 		/* do the XOR */
838 		if (high_crc_set ^ low_data_set) cur = cur ^ CRC32_POLY_BE;
839 	}
840 	return cur;
841 }
842 
843 static unsigned int
844 bmac_crc(unsigned short *address)
845 {
846 	unsigned int newcrc;
847 
848 	XXDEBUG(("bmac_crc: addr=%#04x, %#04x, %#04x\n", *address, address[1], address[2]));
849 	newcrc = crc416(0xffffffff, *address);	/* address bits 47 - 32 */
850 	newcrc = crc416(newcrc, address[1]);	/* address bits 31 - 16 */
851 	newcrc = crc416(newcrc, address[2]);	/* address bits 15 - 0  */
852 
853 	return(newcrc);
854 }
855 
856 /*
857  * Add requested mcast addr to BMac's hash table filter.
858  *
859  */
860 
861 static void
862 bmac_addhash(struct bmac_data *bp, unsigned char *addr)
863 {
864 	unsigned int	 crc;
865 	unsigned short	 mask;
866 
867 	if (!(*addr)) return;
868 	crc = bmac_crc((unsigned short *)addr) & 0x3f; /* Big-endian alert! */
869 	crc = reverse6[crc];	/* Hyperfast bit-reversing algorithm */
870 	if (bp->hash_use_count[crc]++) return; /* This bit is already set */
871 	mask = crc % 16;
872 	mask = (unsigned char)1 << mask;
873 	bp->hash_use_count[crc/16] |= mask;
874 }
875 
876 static void
877 bmac_removehash(struct bmac_data *bp, unsigned char *addr)
878 {
879 	unsigned int crc;
880 	unsigned char mask;
881 
882 	/* Now, delete the address from the filter copy, as indicated */
883 	crc = bmac_crc((unsigned short *)addr) & 0x3f; /* Big-endian alert! */
884 	crc = reverse6[crc];	/* Hyperfast bit-reversing algorithm */
885 	if (bp->hash_use_count[crc] == 0) return; /* That bit wasn't in use! */
886 	if (--bp->hash_use_count[crc]) return; /* That bit is still in use */
887 	mask = crc % 16;
888 	mask = ((unsigned char)1 << mask) ^ 0xffff; /* To turn off bit */
889 	bp->hash_table_mask[crc/16] &= mask;
890 }
891 
892 /*
893  * Sync the adapter with the software copy of the multicast mask
894  *  (logical address filter).
895  */
896 
897 static void
898 bmac_rx_off(struct net_device *dev)
899 {
900 	unsigned short rx_cfg;
901 
902 	rx_cfg = bmread(dev, RXCFG);
903 	rx_cfg &= ~RxMACEnable;
904 	bmwrite(dev, RXCFG, rx_cfg);
905 	do {
906 		rx_cfg = bmread(dev, RXCFG);
907 	}  while (rx_cfg & RxMACEnable);
908 }
909 
910 unsigned short
911 bmac_rx_on(struct net_device *dev, int hash_enable, int promisc_enable)
912 {
913 	unsigned short rx_cfg;
914 
915 	rx_cfg = bmread(dev, RXCFG);
916 	rx_cfg |= RxMACEnable;
917 	if (hash_enable) rx_cfg |= RxHashFilterEnable;
918 	else rx_cfg &= ~RxHashFilterEnable;
919 	if (promisc_enable) rx_cfg |= RxPromiscEnable;
920 	else rx_cfg &= ~RxPromiscEnable;
921 	bmwrite(dev, RXRST, RxResetValue);
922 	bmwrite(dev, RXFIFOCSR, 0);	/* first disable rxFIFO */
923 	bmwrite(dev, RXFIFOCSR, RxFIFOEnable );
924 	bmwrite(dev, RXCFG, rx_cfg );
925 	return rx_cfg;
926 }
927 
928 static void
929 bmac_update_hash_table_mask(struct net_device *dev, struct bmac_data *bp)
930 {
931 	bmwrite(dev, BHASH3, bp->hash_table_mask[0]); /* bits 15 - 0 */
932 	bmwrite(dev, BHASH2, bp->hash_table_mask[1]); /* bits 31 - 16 */
933 	bmwrite(dev, BHASH1, bp->hash_table_mask[2]); /* bits 47 - 32 */
934 	bmwrite(dev, BHASH0, bp->hash_table_mask[3]); /* bits 63 - 48 */
935 }
936 
937 #if 0
938 static void
939 bmac_add_multi(struct net_device *dev,
940 	       struct bmac_data *bp, unsigned char *addr)
941 {
942 	/* XXDEBUG(("bmac: enter bmac_add_multi\n")); */
943 	bmac_addhash(bp, addr);
944 	bmac_rx_off(dev);
945 	bmac_update_hash_table_mask(dev, bp);
946 	bmac_rx_on(dev, 1, (dev->flags & IFF_PROMISC)? 1 : 0);
947 	/* XXDEBUG(("bmac: exit bmac_add_multi\n")); */
948 }
949 
950 static void
951 bmac_remove_multi(struct net_device *dev,
952 		  struct bmac_data *bp, unsigned char *addr)
953 {
954 	bmac_removehash(bp, addr);
955 	bmac_rx_off(dev);
956 	bmac_update_hash_table_mask(dev, bp);
957 	bmac_rx_on(dev, 1, (dev->flags & IFF_PROMISC)? 1 : 0);
958 }
959 #endif
960 
961 /* Set or clear the multicast filter for this adaptor.
962     num_addrs == -1	Promiscuous mode, receive all packets
963     num_addrs == 0	Normal mode, clear multicast list
964     num_addrs > 0	Multicast mode, receive normal and MC packets, and do
965 			best-effort filtering.
966  */
967 static void bmac_set_multicast(struct net_device *dev)
968 {
969 	struct netdev_hw_addr *ha;
970 	struct bmac_data *bp = netdev_priv(dev);
971 	int num_addrs = netdev_mc_count(dev);
972 	unsigned short rx_cfg;
973 	int i;
974 
975 	if (bp->sleeping)
976 		return;
977 
978 	XXDEBUG(("bmac: enter bmac_set_multicast, n_addrs=%d\n", num_addrs));
979 
980 	if((dev->flags & IFF_ALLMULTI) || (netdev_mc_count(dev) > 64)) {
981 		for (i=0; i<4; i++) bp->hash_table_mask[i] = 0xffff;
982 		bmac_update_hash_table_mask(dev, bp);
983 		rx_cfg = bmac_rx_on(dev, 1, 0);
984 		XXDEBUG(("bmac: all multi, rx_cfg=%#08x\n"));
985 	} else if ((dev->flags & IFF_PROMISC) || (num_addrs < 0)) {
986 		rx_cfg = bmread(dev, RXCFG);
987 		rx_cfg |= RxPromiscEnable;
988 		bmwrite(dev, RXCFG, rx_cfg);
989 		rx_cfg = bmac_rx_on(dev, 0, 1);
990 		XXDEBUG(("bmac: promisc mode enabled, rx_cfg=%#08x\n", rx_cfg));
991 	} else {
992 		for (i=0; i<4; i++) bp->hash_table_mask[i] = 0;
993 		for (i=0; i<64; i++) bp->hash_use_count[i] = 0;
994 		if (num_addrs == 0) {
995 			rx_cfg = bmac_rx_on(dev, 0, 0);
996 			XXDEBUG(("bmac: multi disabled, rx_cfg=%#08x\n", rx_cfg));
997 		} else {
998 			netdev_for_each_mc_addr(ha, dev)
999 				bmac_addhash(bp, ha->addr);
1000 			bmac_update_hash_table_mask(dev, bp);
1001 			rx_cfg = bmac_rx_on(dev, 1, 0);
1002 			XXDEBUG(("bmac: multi enabled, rx_cfg=%#08x\n", rx_cfg));
1003 		}
1004 	}
1005 	/* XXDEBUG(("bmac: exit bmac_set_multicast\n")); */
1006 }
1007 #else /* ifdef SUNHME_MULTICAST */
1008 
1009 /* The version of set_multicast below was lifted from sunhme.c */
1010 
1011 static void bmac_set_multicast(struct net_device *dev)
1012 {
1013 	struct netdev_hw_addr *ha;
1014 	unsigned short rx_cfg;
1015 	u32 crc;
1016 
1017 	if((dev->flags & IFF_ALLMULTI) || (netdev_mc_count(dev) > 64)) {
1018 		bmwrite(dev, BHASH0, 0xffff);
1019 		bmwrite(dev, BHASH1, 0xffff);
1020 		bmwrite(dev, BHASH2, 0xffff);
1021 		bmwrite(dev, BHASH3, 0xffff);
1022 	} else if(dev->flags & IFF_PROMISC) {
1023 		rx_cfg = bmread(dev, RXCFG);
1024 		rx_cfg |= RxPromiscEnable;
1025 		bmwrite(dev, RXCFG, rx_cfg);
1026 	} else {
1027 		u16 hash_table[4] = { 0 };
1028 
1029 		rx_cfg = bmread(dev, RXCFG);
1030 		rx_cfg &= ~RxPromiscEnable;
1031 		bmwrite(dev, RXCFG, rx_cfg);
1032 
1033 		netdev_for_each_mc_addr(ha, dev) {
1034 			crc = ether_crc_le(6, ha->addr);
1035 			crc >>= 26;
1036 			hash_table[crc >> 4] |= 1 << (crc & 0xf);
1037 		}
1038 		bmwrite(dev, BHASH0, hash_table[0]);
1039 		bmwrite(dev, BHASH1, hash_table[1]);
1040 		bmwrite(dev, BHASH2, hash_table[2]);
1041 		bmwrite(dev, BHASH3, hash_table[3]);
1042 	}
1043 }
1044 #endif /* SUNHME_MULTICAST */
1045 
1046 static int miscintcount;
1047 
1048 static irqreturn_t bmac_misc_intr(int irq, void *dev_id)
1049 {
1050 	struct net_device *dev = (struct net_device *) dev_id;
1051 	unsigned int status = bmread(dev, STATUS);
1052 	if (miscintcount++ < 10) {
1053 		XXDEBUG(("bmac_misc_intr\n"));
1054 	}
1055 	/* XXDEBUG(("bmac_misc_intr, status=%#08x\n", status)); */
1056 	/*     bmac_txdma_intr_inner(irq, dev_id); */
1057 	/*   if (status & FrameReceived) dev->stats.rx_dropped++; */
1058 	if (status & RxErrorMask) dev->stats.rx_errors++;
1059 	if (status & RxCRCCntExp) dev->stats.rx_crc_errors++;
1060 	if (status & RxLenCntExp) dev->stats.rx_length_errors++;
1061 	if (status & RxOverFlow) dev->stats.rx_over_errors++;
1062 	if (status & RxAlignCntExp) dev->stats.rx_frame_errors++;
1063 
1064 	/*   if (status & FrameSent) dev->stats.tx_dropped++; */
1065 	if (status & TxErrorMask) dev->stats.tx_errors++;
1066 	if (status & TxUnderrun) dev->stats.tx_fifo_errors++;
1067 	if (status & TxNormalCollExp) dev->stats.collisions++;
1068 	return IRQ_HANDLED;
1069 }
1070 
1071 /*
1072  * Procedure for reading EEPROM
1073  */
1074 #define SROMAddressLength	5
1075 #define DataInOn		0x0008
1076 #define DataInOff		0x0000
1077 #define Clk			0x0002
1078 #define ChipSelect		0x0001
1079 #define SDIShiftCount		3
1080 #define SD0ShiftCount		2
1081 #define	DelayValue		1000	/* number of microseconds */
1082 #define SROMStartOffset		10	/* this is in words */
1083 #define SROMReadCount		3	/* number of words to read from SROM */
1084 #define SROMAddressBits		6
1085 #define EnetAddressOffset	20
1086 
1087 static unsigned char
1088 bmac_clock_out_bit(struct net_device *dev)
1089 {
1090 	unsigned short         data;
1091 	unsigned short         val;
1092 
1093 	bmwrite(dev, SROMCSR, ChipSelect | Clk);
1094 	udelay(DelayValue);
1095 
1096 	data = bmread(dev, SROMCSR);
1097 	udelay(DelayValue);
1098 	val = (data >> SD0ShiftCount) & 1;
1099 
1100 	bmwrite(dev, SROMCSR, ChipSelect);
1101 	udelay(DelayValue);
1102 
1103 	return val;
1104 }
1105 
1106 static void
1107 bmac_clock_in_bit(struct net_device *dev, unsigned int val)
1108 {
1109 	unsigned short data;
1110 
1111 	if (val != 0 && val != 1) return;
1112 
1113 	data = (val << SDIShiftCount);
1114 	bmwrite(dev, SROMCSR, data | ChipSelect  );
1115 	udelay(DelayValue);
1116 
1117 	bmwrite(dev, SROMCSR, data | ChipSelect | Clk );
1118 	udelay(DelayValue);
1119 
1120 	bmwrite(dev, SROMCSR, data | ChipSelect);
1121 	udelay(DelayValue);
1122 }
1123 
1124 static void
1125 reset_and_select_srom(struct net_device *dev)
1126 {
1127 	/* first reset */
1128 	bmwrite(dev, SROMCSR, 0);
1129 	udelay(DelayValue);
1130 
1131 	/* send it the read command (110) */
1132 	bmac_clock_in_bit(dev, 1);
1133 	bmac_clock_in_bit(dev, 1);
1134 	bmac_clock_in_bit(dev, 0);
1135 }
1136 
1137 static unsigned short
1138 read_srom(struct net_device *dev, unsigned int addr, unsigned int addr_len)
1139 {
1140 	unsigned short data, val;
1141 	int i;
1142 
1143 	/* send out the address we want to read from */
1144 	for (i = 0; i < addr_len; i++)	{
1145 		val = addr >> (addr_len-i-1);
1146 		bmac_clock_in_bit(dev, val & 1);
1147 	}
1148 
1149 	/* Now read in the 16-bit data */
1150 	data = 0;
1151 	for (i = 0; i < 16; i++)	{
1152 		val = bmac_clock_out_bit(dev);
1153 		data <<= 1;
1154 		data |= val;
1155 	}
1156 	bmwrite(dev, SROMCSR, 0);
1157 
1158 	return data;
1159 }
1160 
1161 /*
1162  * It looks like Cogent and SMC use different methods for calculating
1163  * checksums. What a pain..
1164  */
1165 
1166 static int
1167 bmac_verify_checksum(struct net_device *dev)
1168 {
1169 	unsigned short data, storedCS;
1170 
1171 	reset_and_select_srom(dev);
1172 	data = read_srom(dev, 3, SROMAddressBits);
1173 	storedCS = ((data >> 8) & 0x0ff) | ((data << 8) & 0xff00);
1174 
1175 	return 0;
1176 }
1177 
1178 
1179 static void
1180 bmac_get_station_address(struct net_device *dev, unsigned char *ea)
1181 {
1182 	int i;
1183 	unsigned short data;
1184 
1185 	for (i = 0; i < 6; i++)
1186 		{
1187 			reset_and_select_srom(dev);
1188 			data = read_srom(dev, i + EnetAddressOffset/2, SROMAddressBits);
1189 			ea[2*i]   = bitrev8(data & 0x0ff);
1190 			ea[2*i+1] = bitrev8((data >> 8) & 0x0ff);
1191 		}
1192 }
1193 
1194 static void bmac_reset_and_enable(struct net_device *dev)
1195 {
1196 	struct bmac_data *bp = netdev_priv(dev);
1197 	unsigned long flags;
1198 	struct sk_buff *skb;
1199 	unsigned char *data;
1200 
1201 	spin_lock_irqsave(&bp->lock, flags);
1202 	bmac_enable_and_reset_chip(dev);
1203 	bmac_init_tx_ring(bp);
1204 	bmac_init_rx_ring(dev);
1205 	bmac_init_chip(dev);
1206 	bmac_start_chip(dev);
1207 	bmwrite(dev, INTDISABLE, EnableNormal);
1208 	bp->sleeping = 0;
1209 
1210 	/*
1211 	 * It seems that the bmac can't receive until it's transmitted
1212 	 * a packet.  So we give it a dummy packet to transmit.
1213 	 */
1214 	skb = netdev_alloc_skb(dev, ETHERMINPACKET);
1215 	if (skb != NULL) {
1216 		data = skb_put_zero(skb, ETHERMINPACKET);
1217 		memcpy(data, dev->dev_addr, ETH_ALEN);
1218 		memcpy(data + ETH_ALEN, dev->dev_addr, ETH_ALEN);
1219 		bmac_transmit_packet(skb, dev);
1220 	}
1221 	spin_unlock_irqrestore(&bp->lock, flags);
1222 }
1223 
1224 static const struct ethtool_ops bmac_ethtool_ops = {
1225 	.get_link		= ethtool_op_get_link,
1226 };
1227 
1228 static const struct net_device_ops bmac_netdev_ops = {
1229 	.ndo_open		= bmac_open,
1230 	.ndo_stop		= bmac_close,
1231 	.ndo_start_xmit		= bmac_output,
1232 	.ndo_set_rx_mode	= bmac_set_multicast,
1233 	.ndo_set_mac_address	= bmac_set_address,
1234 	.ndo_validate_addr	= eth_validate_addr,
1235 };
1236 
1237 static int bmac_probe(struct macio_dev *mdev, const struct of_device_id *match)
1238 {
1239 	int j, rev, ret;
1240 	struct bmac_data *bp;
1241 	const unsigned char *prop_addr;
1242 	unsigned char addr[6];
1243 	struct net_device *dev;
1244 	int is_bmac_plus = ((int)match->data) != 0;
1245 
1246 	if (macio_resource_count(mdev) != 3 || macio_irq_count(mdev) != 3) {
1247 		printk(KERN_ERR "BMAC: can't use, need 3 addrs and 3 intrs\n");
1248 		return -ENODEV;
1249 	}
1250 	prop_addr = of_get_property(macio_get_of_node(mdev),
1251 			"mac-address", NULL);
1252 	if (prop_addr == NULL) {
1253 		prop_addr = of_get_property(macio_get_of_node(mdev),
1254 				"local-mac-address", NULL);
1255 		if (prop_addr == NULL) {
1256 			printk(KERN_ERR "BMAC: Can't get mac-address\n");
1257 			return -ENODEV;
1258 		}
1259 	}
1260 	memcpy(addr, prop_addr, sizeof(addr));
1261 
1262 	dev = alloc_etherdev(PRIV_BYTES);
1263 	if (!dev)
1264 		return -ENOMEM;
1265 
1266 	bp = netdev_priv(dev);
1267 	SET_NETDEV_DEV(dev, &mdev->ofdev.dev);
1268 	macio_set_drvdata(mdev, dev);
1269 
1270 	bp->mdev = mdev;
1271 	spin_lock_init(&bp->lock);
1272 
1273 	if (macio_request_resources(mdev, "bmac")) {
1274 		printk(KERN_ERR "BMAC: can't request IO resource !\n");
1275 		goto out_free;
1276 	}
1277 
1278 	dev->base_addr = (unsigned long)
1279 		ioremap(macio_resource_start(mdev, 0), macio_resource_len(mdev, 0));
1280 	if (dev->base_addr == 0)
1281 		goto out_release;
1282 
1283 	dev->irq = macio_irq(mdev, 0);
1284 
1285 	bmac_enable_and_reset_chip(dev);
1286 	bmwrite(dev, INTDISABLE, DisableAll);
1287 
1288 	rev = addr[0] == 0 && addr[1] == 0xA0;
1289 	for (j = 0; j < 6; ++j)
1290 		dev->dev_addr[j] = rev ? bitrev8(addr[j]): addr[j];
1291 
1292 	/* Enable chip without interrupts for now */
1293 	bmac_enable_and_reset_chip(dev);
1294 	bmwrite(dev, INTDISABLE, DisableAll);
1295 
1296 	dev->netdev_ops = &bmac_netdev_ops;
1297 	dev->ethtool_ops = &bmac_ethtool_ops;
1298 
1299 	bmac_get_station_address(dev, addr);
1300 	if (bmac_verify_checksum(dev) != 0)
1301 		goto err_out_iounmap;
1302 
1303 	bp->is_bmac_plus = is_bmac_plus;
1304 	bp->tx_dma = ioremap(macio_resource_start(mdev, 1), macio_resource_len(mdev, 1));
1305 	if (!bp->tx_dma)
1306 		goto err_out_iounmap;
1307 	bp->tx_dma_intr = macio_irq(mdev, 1);
1308 	bp->rx_dma = ioremap(macio_resource_start(mdev, 2), macio_resource_len(mdev, 2));
1309 	if (!bp->rx_dma)
1310 		goto err_out_iounmap_tx;
1311 	bp->rx_dma_intr = macio_irq(mdev, 2);
1312 
1313 	bp->tx_cmds = (volatile struct dbdma_cmd *) DBDMA_ALIGN(bp + 1);
1314 	bp->rx_cmds = bp->tx_cmds + N_TX_RING + 1;
1315 
1316 	bp->queue = (struct sk_buff_head *)(bp->rx_cmds + N_RX_RING + 1);
1317 	skb_queue_head_init(bp->queue);
1318 
1319 	timer_setup(&bp->tx_timeout, bmac_tx_timeout, 0);
1320 
1321 	ret = request_irq(dev->irq, bmac_misc_intr, 0, "BMAC-misc", dev);
1322 	if (ret) {
1323 		printk(KERN_ERR "BMAC: can't get irq %d\n", dev->irq);
1324 		goto err_out_iounmap_rx;
1325 	}
1326 	ret = request_irq(bp->tx_dma_intr, bmac_txdma_intr, 0, "BMAC-txdma", dev);
1327 	if (ret) {
1328 		printk(KERN_ERR "BMAC: can't get irq %d\n", bp->tx_dma_intr);
1329 		goto err_out_irq0;
1330 	}
1331 	ret = request_irq(bp->rx_dma_intr, bmac_rxdma_intr, 0, "BMAC-rxdma", dev);
1332 	if (ret) {
1333 		printk(KERN_ERR "BMAC: can't get irq %d\n", bp->rx_dma_intr);
1334 		goto err_out_irq1;
1335 	}
1336 
1337 	/* Mask chip interrupts and disable chip, will be
1338 	 * re-enabled on open()
1339 	 */
1340 	disable_irq(dev->irq);
1341 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
1342 
1343 	if (register_netdev(dev) != 0) {
1344 		printk(KERN_ERR "BMAC: Ethernet registration failed\n");
1345 		goto err_out_irq2;
1346 	}
1347 
1348 	printk(KERN_INFO "%s: BMAC%s at %pM",
1349 	       dev->name, (is_bmac_plus ? "+" : ""), dev->dev_addr);
1350 	XXDEBUG((", base_addr=%#0lx", dev->base_addr));
1351 	printk("\n");
1352 
1353 	return 0;
1354 
1355 err_out_irq2:
1356 	free_irq(bp->rx_dma_intr, dev);
1357 err_out_irq1:
1358 	free_irq(bp->tx_dma_intr, dev);
1359 err_out_irq0:
1360 	free_irq(dev->irq, dev);
1361 err_out_iounmap_rx:
1362 	iounmap(bp->rx_dma);
1363 err_out_iounmap_tx:
1364 	iounmap(bp->tx_dma);
1365 err_out_iounmap:
1366 	iounmap((void __iomem *)dev->base_addr);
1367 out_release:
1368 	macio_release_resources(mdev);
1369 out_free:
1370 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
1371 	free_netdev(dev);
1372 
1373 	return -ENODEV;
1374 }
1375 
1376 static int bmac_open(struct net_device *dev)
1377 {
1378 	struct bmac_data *bp = netdev_priv(dev);
1379 	/* XXDEBUG(("bmac: enter open\n")); */
1380 	/* reset the chip */
1381 	bp->opened = 1;
1382 	bmac_reset_and_enable(dev);
1383 	enable_irq(dev->irq);
1384 	return 0;
1385 }
1386 
1387 static int bmac_close(struct net_device *dev)
1388 {
1389 	struct bmac_data *bp = netdev_priv(dev);
1390 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
1391 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
1392 	unsigned short config;
1393 	int i;
1394 
1395 	bp->sleeping = 1;
1396 
1397 	/* disable rx and tx */
1398 	config = bmread(dev, RXCFG);
1399 	bmwrite(dev, RXCFG, (config & ~RxMACEnable));
1400 
1401 	config = bmread(dev, TXCFG);
1402 	bmwrite(dev, TXCFG, (config & ~TxMACEnable));
1403 
1404 	bmwrite(dev, INTDISABLE, DisableAll); /* disable all intrs */
1405 
1406 	/* disable rx and tx dma */
1407 	rd->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
1408 	td->control = cpu_to_le32(DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE));	/* clear run bit */
1409 
1410 	/* free some skb's */
1411 	XXDEBUG(("bmac: free rx bufs\n"));
1412 	for (i=0; i<N_RX_RING; i++) {
1413 		if (bp->rx_bufs[i] != NULL) {
1414 			dev_kfree_skb(bp->rx_bufs[i]);
1415 			bp->rx_bufs[i] = NULL;
1416 		}
1417 	}
1418 	XXDEBUG(("bmac: free tx bufs\n"));
1419 	for (i = 0; i<N_TX_RING; i++) {
1420 		if (bp->tx_bufs[i] != NULL) {
1421 			dev_kfree_skb(bp->tx_bufs[i]);
1422 			bp->tx_bufs[i] = NULL;
1423 		}
1424 	}
1425 	XXDEBUG(("bmac: all bufs freed\n"));
1426 
1427 	bp->opened = 0;
1428 	disable_irq(dev->irq);
1429 	pmac_call_feature(PMAC_FTR_BMAC_ENABLE, macio_get_of_node(bp->mdev), 0, 0);
1430 
1431 	return 0;
1432 }
1433 
1434 static void
1435 bmac_start(struct net_device *dev)
1436 {
1437 	struct bmac_data *bp = netdev_priv(dev);
1438 	int i;
1439 	struct sk_buff *skb;
1440 	unsigned long flags;
1441 
1442 	if (bp->sleeping)
1443 		return;
1444 
1445 	spin_lock_irqsave(&bp->lock, flags);
1446 	while (1) {
1447 		i = bp->tx_fill + 1;
1448 		if (i >= N_TX_RING)
1449 			i = 0;
1450 		if (i == bp->tx_empty)
1451 			break;
1452 		skb = skb_dequeue(bp->queue);
1453 		if (skb == NULL)
1454 			break;
1455 		bmac_transmit_packet(skb, dev);
1456 	}
1457 	spin_unlock_irqrestore(&bp->lock, flags);
1458 }
1459 
1460 static netdev_tx_t
1461 bmac_output(struct sk_buff *skb, struct net_device *dev)
1462 {
1463 	struct bmac_data *bp = netdev_priv(dev);
1464 	skb_queue_tail(bp->queue, skb);
1465 	bmac_start(dev);
1466 	return NETDEV_TX_OK;
1467 }
1468 
1469 static void bmac_tx_timeout(struct timer_list *t)
1470 {
1471 	struct bmac_data *bp = from_timer(bp, t, tx_timeout);
1472 	struct net_device *dev = macio_get_drvdata(bp->mdev);
1473 	volatile struct dbdma_regs __iomem *td = bp->tx_dma;
1474 	volatile struct dbdma_regs __iomem *rd = bp->rx_dma;
1475 	volatile struct dbdma_cmd *cp;
1476 	unsigned long flags;
1477 	unsigned short config, oldConfig;
1478 	int i;
1479 
1480 	XXDEBUG(("bmac: tx_timeout called\n"));
1481 	spin_lock_irqsave(&bp->lock, flags);
1482 	bp->timeout_active = 0;
1483 
1484 	/* update various counters */
1485 /*     	bmac_handle_misc_intrs(bp, 0); */
1486 
1487 	cp = &bp->tx_cmds[bp->tx_empty];
1488 /*	XXDEBUG((KERN_DEBUG "bmac: tx dmastat=%x %x runt=%d pr=%x fs=%x fc=%x\n", */
1489 /* 	   le32_to_cpu(td->status), le16_to_cpu(cp->xfer_status), bp->tx_bad_runt, */
1490 /* 	   mb->pr, mb->xmtfs, mb->fifofc)); */
1491 
1492 	/* turn off both tx and rx and reset the chip */
1493 	config = bmread(dev, RXCFG);
1494 	bmwrite(dev, RXCFG, (config & ~RxMACEnable));
1495 	config = bmread(dev, TXCFG);
1496 	bmwrite(dev, TXCFG, (config & ~TxMACEnable));
1497 	out_le32(&td->control, DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE|ACTIVE|DEAD));
1498 	printk(KERN_ERR "bmac: transmit timeout - resetting\n");
1499 	bmac_enable_and_reset_chip(dev);
1500 
1501 	/* restart rx dma */
1502 	cp = bus_to_virt(le32_to_cpu(rd->cmdptr));
1503 	out_le32(&rd->control, DBDMA_CLEAR(RUN|PAUSE|FLUSH|WAKE|ACTIVE|DEAD));
1504 	out_le16(&cp->xfer_status, 0);
1505 	out_le32(&rd->cmdptr, virt_to_bus(cp));
1506 	out_le32(&rd->control, DBDMA_SET(RUN|WAKE));
1507 
1508 	/* fix up the transmit side */
1509 	XXDEBUG((KERN_DEBUG "bmac: tx empty=%d fill=%d fullup=%d\n",
1510 		 bp->tx_empty, bp->tx_fill, bp->tx_fullup));
1511 	i = bp->tx_empty;
1512 	++dev->stats.tx_errors;
1513 	if (i != bp->tx_fill) {
1514 		dev_kfree_skb(bp->tx_bufs[i]);
1515 		bp->tx_bufs[i] = NULL;
1516 		if (++i >= N_TX_RING) i = 0;
1517 		bp->tx_empty = i;
1518 	}
1519 	bp->tx_fullup = 0;
1520 	netif_wake_queue(dev);
1521 	if (i != bp->tx_fill) {
1522 		cp = &bp->tx_cmds[i];
1523 		out_le16(&cp->xfer_status, 0);
1524 		out_le16(&cp->command, OUTPUT_LAST);
1525 		out_le32(&td->cmdptr, virt_to_bus(cp));
1526 		out_le32(&td->control, DBDMA_SET(RUN));
1527 		/* 	bmac_set_timeout(dev); */
1528 		XXDEBUG((KERN_DEBUG "bmac: starting %d\n", i));
1529 	}
1530 
1531 	/* turn it back on */
1532 	oldConfig = bmread(dev, RXCFG);
1533 	bmwrite(dev, RXCFG, oldConfig | RxMACEnable );
1534 	oldConfig = bmread(dev, TXCFG);
1535 	bmwrite(dev, TXCFG, oldConfig | TxMACEnable );
1536 
1537 	spin_unlock_irqrestore(&bp->lock, flags);
1538 }
1539 
1540 #if 0
1541 static void dump_dbdma(volatile struct dbdma_cmd *cp,int count)
1542 {
1543 	int i,*ip;
1544 
1545 	for (i=0;i< count;i++) {
1546 		ip = (int*)(cp+i);
1547 
1548 		printk("dbdma req 0x%x addr 0x%x baddr 0x%x xfer/res 0x%x\n",
1549 		       le32_to_cpup(ip+0),
1550 		       le32_to_cpup(ip+1),
1551 		       le32_to_cpup(ip+2),
1552 		       le32_to_cpup(ip+3));
1553 	}
1554 
1555 }
1556 #endif
1557 
1558 #if 0
1559 static int
1560 bmac_proc_info(char *buffer, char **start, off_t offset, int length)
1561 {
1562 	int len = 0;
1563 	off_t pos   = 0;
1564 	off_t begin = 0;
1565 	int i;
1566 
1567 	if (bmac_devs == NULL)
1568 		return -ENOSYS;
1569 
1570 	len += sprintf(buffer, "BMAC counters & registers\n");
1571 
1572 	for (i = 0; i<N_REG_ENTRIES; i++) {
1573 		len += sprintf(buffer + len, "%s: %#08x\n",
1574 			       reg_entries[i].name,
1575 			       bmread(bmac_devs, reg_entries[i].reg_offset));
1576 		pos = begin + len;
1577 
1578 		if (pos < offset) {
1579 			len = 0;
1580 			begin = pos;
1581 		}
1582 
1583 		if (pos > offset+length) break;
1584 	}
1585 
1586 	*start = buffer + (offset - begin);
1587 	len -= (offset - begin);
1588 
1589 	if (len > length) len = length;
1590 
1591 	return len;
1592 }
1593 #endif
1594 
1595 static int bmac_remove(struct macio_dev *mdev)
1596 {
1597 	struct net_device *dev = macio_get_drvdata(mdev);
1598 	struct bmac_data *bp = netdev_priv(dev);
1599 
1600 	unregister_netdev(dev);
1601 
1602        	free_irq(dev->irq, dev);
1603 	free_irq(bp->tx_dma_intr, dev);
1604 	free_irq(bp->rx_dma_intr, dev);
1605 
1606 	iounmap((void __iomem *)dev->base_addr);
1607 	iounmap(bp->tx_dma);
1608 	iounmap(bp->rx_dma);
1609 
1610 	macio_release_resources(mdev);
1611 
1612 	free_netdev(dev);
1613 
1614 	return 0;
1615 }
1616 
1617 static const struct of_device_id bmac_match[] =
1618 {
1619 	{
1620 	.name 		= "bmac",
1621 	.data		= (void *)0,
1622 	},
1623 	{
1624 	.type		= "network",
1625 	.compatible	= "bmac+",
1626 	.data		= (void *)1,
1627 	},
1628 	{},
1629 };
1630 MODULE_DEVICE_TABLE (of, bmac_match);
1631 
1632 static struct macio_driver bmac_driver =
1633 {
1634 	.driver = {
1635 		.name 		= "bmac",
1636 		.owner		= THIS_MODULE,
1637 		.of_match_table	= bmac_match,
1638 	},
1639 	.probe		= bmac_probe,
1640 	.remove		= bmac_remove,
1641 #ifdef CONFIG_PM
1642 	.suspend	= bmac_suspend,
1643 	.resume		= bmac_resume,
1644 #endif
1645 };
1646 
1647 
1648 static int __init bmac_init(void)
1649 {
1650 	if (bmac_emergency_rxbuf == NULL) {
1651 		bmac_emergency_rxbuf = kmalloc(RX_BUFLEN, GFP_KERNEL);
1652 		if (bmac_emergency_rxbuf == NULL)
1653 			return -ENOMEM;
1654 	}
1655 
1656 	return macio_register_driver(&bmac_driver);
1657 }
1658 
1659 static void __exit bmac_exit(void)
1660 {
1661 	macio_unregister_driver(&bmac_driver);
1662 
1663 	kfree(bmac_emergency_rxbuf);
1664 	bmac_emergency_rxbuf = NULL;
1665 }
1666 
1667 MODULE_AUTHOR("Randy Gobbel/Paul Mackerras");
1668 MODULE_DESCRIPTION("PowerMac BMAC ethernet driver.");
1669 MODULE_LICENSE("GPL");
1670 
1671 module_init(bmac_init);
1672 module_exit(bmac_exit);
1673