xref: /linux/drivers/net/ethernet/apple/mace.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Network device driver for the MACE ethernet controller on
4  * Apple Powermacs.  Assumes it's under a DBDMA controller.
5  *
6  * Copyright (C) 1996 Paul Mackerras.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/netdevice.h>
12 #include <linux/etherdevice.h>
13 #include <linux/delay.h>
14 #include <linux/string.h>
15 #include <linux/timer.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/crc32.h>
19 #include <linux/spinlock.h>
20 #include <linux/bitrev.h>
21 #include <linux/slab.h>
22 #include <linux/pgtable.h>
23 #include <asm/dbdma.h>
24 #include <asm/io.h>
25 #include <asm/macio.h>
26 
27 #include "mace.h"
28 
29 static int port_aaui = -1;
30 
31 #define N_RX_RING	8
32 #define N_TX_RING	6
33 #define MAX_TX_ACTIVE	1
34 #define NCMDS_TX	1	/* dma commands per element in tx ring */
35 #define RX_BUFLEN	(ETH_FRAME_LEN + 8)
36 #define TX_TIMEOUT	HZ	/* 1 second */
37 
38 /* Chip rev needs workaround on HW & multicast addr change */
39 #define BROKEN_ADDRCHG_REV	0x0941
40 
41 /* Bits in transmit DMA status */
42 #define TX_DMA_ERR	0x80
43 
44 struct mace_data {
45     volatile struct mace __iomem *mace;
46     volatile struct dbdma_regs __iomem *tx_dma;
47     int tx_dma_intr;
48     volatile struct dbdma_regs __iomem *rx_dma;
49     int rx_dma_intr;
50     volatile struct dbdma_cmd *tx_cmds;	/* xmit dma command list */
51     volatile struct dbdma_cmd *rx_cmds;	/* recv dma command list */
52     struct sk_buff *rx_bufs[N_RX_RING];
53     int rx_fill;
54     int rx_empty;
55     struct sk_buff *tx_bufs[N_TX_RING];
56     int tx_fill;
57     int tx_empty;
58     unsigned char maccc;
59     unsigned char tx_fullup;
60     unsigned char tx_active;
61     unsigned char tx_bad_runt;
62     struct timer_list tx_timeout;
63     int timeout_active;
64     int port_aaui;
65     int chipid;
66     struct macio_dev *mdev;
67     spinlock_t lock;
68 };
69 
70 /*
71  * Number of bytes of private data per MACE: allow enough for
72  * the rx and tx dma commands plus a branch dma command each,
73  * and another 16 bytes to allow us to align the dma command
74  * buffers on a 16 byte boundary.
75  */
76 #define PRIV_BYTES	(sizeof(struct mace_data) \
77 	+ (N_RX_RING + NCMDS_TX * N_TX_RING + 3) * sizeof(struct dbdma_cmd))
78 
79 static int mace_open(struct net_device *dev);
80 static int mace_close(struct net_device *dev);
81 static netdev_tx_t mace_xmit_start(struct sk_buff *skb, struct net_device *dev);
82 static void mace_set_multicast(struct net_device *dev);
83 static void mace_reset(struct net_device *dev);
84 static int mace_set_address(struct net_device *dev, void *addr);
85 static irqreturn_t mace_interrupt(int irq, void *dev_id);
86 static irqreturn_t mace_txdma_intr(int irq, void *dev_id);
87 static irqreturn_t mace_rxdma_intr(int irq, void *dev_id);
88 static void mace_set_timeout(struct net_device *dev);
89 static void mace_tx_timeout(struct timer_list *t);
90 static inline void dbdma_reset(volatile struct dbdma_regs __iomem *dma);
91 static inline void mace_clean_rings(struct mace_data *mp);
92 static void __mace_set_address(struct net_device *dev, const void *addr);
93 
94 /*
95  * If we can't get a skbuff when we need it, we use this area for DMA.
96  */
97 static unsigned char *dummy_buf;
98 
99 static const struct net_device_ops mace_netdev_ops = {
100 	.ndo_open		= mace_open,
101 	.ndo_stop		= mace_close,
102 	.ndo_start_xmit		= mace_xmit_start,
103 	.ndo_set_rx_mode	= mace_set_multicast,
104 	.ndo_set_mac_address	= mace_set_address,
105 	.ndo_validate_addr	= eth_validate_addr,
106 };
107 
108 static int mace_probe(struct macio_dev *mdev, const struct of_device_id *match)
109 {
110 	struct device_node *mace = macio_get_of_node(mdev);
111 	struct net_device *dev;
112 	struct mace_data *mp;
113 	const unsigned char *addr;
114 	u8 macaddr[ETH_ALEN];
115 	int j, rev, rc = -EBUSY;
116 
117 	if (macio_resource_count(mdev) != 3 || macio_irq_count(mdev) != 3) {
118 		printk(KERN_ERR "can't use MACE %pOF: need 3 addrs and 3 irqs\n",
119 		       mace);
120 		return -ENODEV;
121 	}
122 
123 	addr = of_get_property(mace, "mac-address", NULL);
124 	if (addr == NULL) {
125 		addr = of_get_property(mace, "local-mac-address", NULL);
126 		if (addr == NULL) {
127 			printk(KERN_ERR "Can't get mac-address for MACE %pOF\n",
128 			       mace);
129 			return -ENODEV;
130 		}
131 	}
132 
133 	/*
134 	 * lazy allocate the driver-wide dummy buffer. (Note that we
135 	 * never have more than one MACE in the system anyway)
136 	 */
137 	if (dummy_buf == NULL) {
138 		dummy_buf = kmalloc(RX_BUFLEN+2, GFP_KERNEL);
139 		if (dummy_buf == NULL)
140 			return -ENOMEM;
141 	}
142 
143 	if (macio_request_resources(mdev, "mace")) {
144 		printk(KERN_ERR "MACE: can't request IO resources !\n");
145 		return -EBUSY;
146 	}
147 
148 	dev = alloc_etherdev(PRIV_BYTES);
149 	if (!dev) {
150 		rc = -ENOMEM;
151 		goto err_release;
152 	}
153 	SET_NETDEV_DEV(dev, &mdev->ofdev.dev);
154 
155 	mp = netdev_priv(dev);
156 	mp->mdev = mdev;
157 	macio_set_drvdata(mdev, dev);
158 
159 	dev->base_addr = macio_resource_start(mdev, 0);
160 	mp->mace = ioremap(dev->base_addr, 0x1000);
161 	if (mp->mace == NULL) {
162 		printk(KERN_ERR "MACE: can't map IO resources !\n");
163 		rc = -ENOMEM;
164 		goto err_free;
165 	}
166 	dev->irq = macio_irq(mdev, 0);
167 
168 	rev = addr[0] == 0 && addr[1] == 0xA0;
169 	for (j = 0; j < 6; ++j) {
170 		macaddr[j] = rev ? bitrev8(addr[j]): addr[j];
171 	}
172 	eth_hw_addr_set(dev, macaddr);
173 	mp->chipid = (in_8(&mp->mace->chipid_hi) << 8) |
174 			in_8(&mp->mace->chipid_lo);
175 
176 
177 	mp = netdev_priv(dev);
178 	mp->maccc = ENXMT | ENRCV;
179 
180 	mp->tx_dma = ioremap(macio_resource_start(mdev, 1), 0x1000);
181 	if (mp->tx_dma == NULL) {
182 		printk(KERN_ERR "MACE: can't map TX DMA resources !\n");
183 		rc = -ENOMEM;
184 		goto err_unmap_io;
185 	}
186 	mp->tx_dma_intr = macio_irq(mdev, 1);
187 
188 	mp->rx_dma = ioremap(macio_resource_start(mdev, 2), 0x1000);
189 	if (mp->rx_dma == NULL) {
190 		printk(KERN_ERR "MACE: can't map RX DMA resources !\n");
191 		rc = -ENOMEM;
192 		goto err_unmap_tx_dma;
193 	}
194 	mp->rx_dma_intr = macio_irq(mdev, 2);
195 
196 	mp->tx_cmds = (volatile struct dbdma_cmd *) DBDMA_ALIGN(mp + 1);
197 	mp->rx_cmds = mp->tx_cmds + NCMDS_TX * N_TX_RING + 1;
198 
199 	memset((char *) mp->tx_cmds, 0,
200 	       (NCMDS_TX*N_TX_RING + N_RX_RING + 2) * sizeof(struct dbdma_cmd));
201 	timer_setup(&mp->tx_timeout, mace_tx_timeout, 0);
202 	spin_lock_init(&mp->lock);
203 	mp->timeout_active = 0;
204 
205 	if (port_aaui >= 0)
206 		mp->port_aaui = port_aaui;
207 	else {
208 		/* Apple Network Server uses the AAUI port */
209 		if (of_machine_is_compatible("AAPL,ShinerESB"))
210 			mp->port_aaui = 1;
211 		else {
212 #ifdef CONFIG_MACE_AAUI_PORT
213 			mp->port_aaui = 1;
214 #else
215 			mp->port_aaui = 0;
216 #endif
217 		}
218 	}
219 
220 	dev->netdev_ops = &mace_netdev_ops;
221 
222 	/*
223 	 * Most of what is below could be moved to mace_open()
224 	 */
225 	mace_reset(dev);
226 
227 	rc = request_irq(dev->irq, mace_interrupt, 0, "MACE", dev);
228 	if (rc) {
229 		printk(KERN_ERR "MACE: can't get irq %d\n", dev->irq);
230 		goto err_unmap_rx_dma;
231 	}
232 	rc = request_irq(mp->tx_dma_intr, mace_txdma_intr, 0, "MACE-txdma", dev);
233 	if (rc) {
234 		printk(KERN_ERR "MACE: can't get irq %d\n", mp->tx_dma_intr);
235 		goto err_free_irq;
236 	}
237 	rc = request_irq(mp->rx_dma_intr, mace_rxdma_intr, 0, "MACE-rxdma", dev);
238 	if (rc) {
239 		printk(KERN_ERR "MACE: can't get irq %d\n", mp->rx_dma_intr);
240 		goto err_free_tx_irq;
241 	}
242 
243 	rc = register_netdev(dev);
244 	if (rc) {
245 		printk(KERN_ERR "MACE: Cannot register net device, aborting.\n");
246 		goto err_free_rx_irq;
247 	}
248 
249 	printk(KERN_INFO "%s: MACE at %pM, chip revision %d.%d\n",
250 	       dev->name, dev->dev_addr,
251 	       mp->chipid >> 8, mp->chipid & 0xff);
252 
253 	return 0;
254 
255  err_free_rx_irq:
256 	free_irq(macio_irq(mdev, 2), dev);
257  err_free_tx_irq:
258 	free_irq(macio_irq(mdev, 1), dev);
259  err_free_irq:
260 	free_irq(macio_irq(mdev, 0), dev);
261  err_unmap_rx_dma:
262 	iounmap(mp->rx_dma);
263  err_unmap_tx_dma:
264 	iounmap(mp->tx_dma);
265  err_unmap_io:
266 	iounmap(mp->mace);
267  err_free:
268 	free_netdev(dev);
269  err_release:
270 	macio_release_resources(mdev);
271 
272 	return rc;
273 }
274 
275 static void mace_remove(struct macio_dev *mdev)
276 {
277 	struct net_device *dev = macio_get_drvdata(mdev);
278 	struct mace_data *mp;
279 
280 	BUG_ON(dev == NULL);
281 
282 	macio_set_drvdata(mdev, NULL);
283 
284 	mp = netdev_priv(dev);
285 
286 	unregister_netdev(dev);
287 
288 	free_irq(dev->irq, dev);
289 	free_irq(mp->tx_dma_intr, dev);
290 	free_irq(mp->rx_dma_intr, dev);
291 
292 	iounmap(mp->rx_dma);
293 	iounmap(mp->tx_dma);
294 	iounmap(mp->mace);
295 
296 	free_netdev(dev);
297 
298 	macio_release_resources(mdev);
299 }
300 
301 static void dbdma_reset(volatile struct dbdma_regs __iomem *dma)
302 {
303     int i;
304 
305     out_le32(&dma->control, (WAKE|FLUSH|PAUSE|RUN) << 16);
306 
307     /*
308      * Yes this looks peculiar, but apparently it needs to be this
309      * way on some machines.
310      */
311     for (i = 200; i > 0; --i)
312 	if (le32_to_cpu(dma->control) & RUN)
313 	    udelay(1);
314 }
315 
316 static void mace_reset(struct net_device *dev)
317 {
318     struct mace_data *mp = netdev_priv(dev);
319     volatile struct mace __iomem *mb = mp->mace;
320     int i;
321 
322     /* soft-reset the chip */
323     i = 200;
324     while (--i) {
325 	out_8(&mb->biucc, SWRST);
326 	if (in_8(&mb->biucc) & SWRST) {
327 	    udelay(10);
328 	    continue;
329 	}
330 	break;
331     }
332     if (!i) {
333 	printk(KERN_ERR "mace: cannot reset chip!\n");
334 	return;
335     }
336 
337     out_8(&mb->imr, 0xff);	/* disable all intrs for now */
338     i = in_8(&mb->ir);
339     out_8(&mb->maccc, 0);	/* turn off tx, rx */
340 
341     out_8(&mb->biucc, XMTSP_64);
342     out_8(&mb->utr, RTRD);
343     out_8(&mb->fifocc, RCVFW_32 | XMTFW_16 | XMTFWU | RCVFWU | XMTBRST);
344     out_8(&mb->xmtfc, AUTO_PAD_XMIT); /* auto-pad short frames */
345     out_8(&mb->rcvfc, 0);
346 
347     /* load up the hardware address */
348     __mace_set_address(dev, dev->dev_addr);
349 
350     /* clear the multicast filter */
351     if (mp->chipid == BROKEN_ADDRCHG_REV)
352 	out_8(&mb->iac, LOGADDR);
353     else {
354 	out_8(&mb->iac, ADDRCHG | LOGADDR);
355 	while ((in_8(&mb->iac) & ADDRCHG) != 0)
356 		;
357     }
358     for (i = 0; i < 8; ++i)
359 	out_8(&mb->ladrf, 0);
360 
361     /* done changing address */
362     if (mp->chipid != BROKEN_ADDRCHG_REV)
363 	out_8(&mb->iac, 0);
364 
365     if (mp->port_aaui)
366 	out_8(&mb->plscc, PORTSEL_AUI + ENPLSIO);
367     else
368 	out_8(&mb->plscc, PORTSEL_GPSI + ENPLSIO);
369 }
370 
371 static void __mace_set_address(struct net_device *dev, const void *addr)
372 {
373     struct mace_data *mp = netdev_priv(dev);
374     volatile struct mace __iomem *mb = mp->mace;
375     const unsigned char *p = addr;
376     u8 macaddr[ETH_ALEN];
377     int i;
378 
379     /* load up the hardware address */
380     if (mp->chipid == BROKEN_ADDRCHG_REV)
381 	out_8(&mb->iac, PHYADDR);
382     else {
383 	out_8(&mb->iac, ADDRCHG | PHYADDR);
384 	while ((in_8(&mb->iac) & ADDRCHG) != 0)
385 	    ;
386     }
387     for (i = 0; i < 6; ++i)
388         out_8(&mb->padr, macaddr[i] = p[i]);
389 
390     eth_hw_addr_set(dev, macaddr);
391 
392     if (mp->chipid != BROKEN_ADDRCHG_REV)
393         out_8(&mb->iac, 0);
394 }
395 
396 static int mace_set_address(struct net_device *dev, void *addr)
397 {
398     struct mace_data *mp = netdev_priv(dev);
399     volatile struct mace __iomem *mb = mp->mace;
400     unsigned long flags;
401 
402     spin_lock_irqsave(&mp->lock, flags);
403 
404     __mace_set_address(dev, addr);
405 
406     /* note: setting ADDRCHG clears ENRCV */
407     out_8(&mb->maccc, mp->maccc);
408 
409     spin_unlock_irqrestore(&mp->lock, flags);
410     return 0;
411 }
412 
413 static inline void mace_clean_rings(struct mace_data *mp)
414 {
415     int i;
416 
417     /* free some skb's */
418     for (i = 0; i < N_RX_RING; ++i) {
419 	if (mp->rx_bufs[i] != NULL) {
420 	    dev_kfree_skb(mp->rx_bufs[i]);
421 	    mp->rx_bufs[i] = NULL;
422 	}
423     }
424     for (i = mp->tx_empty; i != mp->tx_fill; ) {
425 	dev_kfree_skb(mp->tx_bufs[i]);
426 	if (++i >= N_TX_RING)
427 	    i = 0;
428     }
429 }
430 
431 static int mace_open(struct net_device *dev)
432 {
433     struct mace_data *mp = netdev_priv(dev);
434     volatile struct mace __iomem *mb = mp->mace;
435     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
436     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
437     volatile struct dbdma_cmd *cp;
438     int i;
439     struct sk_buff *skb;
440     unsigned char *data;
441 
442     /* reset the chip */
443     mace_reset(dev);
444 
445     /* initialize list of sk_buffs for receiving and set up recv dma */
446     mace_clean_rings(mp);
447     memset((char *)mp->rx_cmds, 0, N_RX_RING * sizeof(struct dbdma_cmd));
448     cp = mp->rx_cmds;
449     for (i = 0; i < N_RX_RING - 1; ++i) {
450 	skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
451 	if (!skb) {
452 	    data = dummy_buf;
453 	} else {
454 	    skb_reserve(skb, 2);	/* so IP header lands on 4-byte bdry */
455 	    data = skb->data;
456 	}
457 	mp->rx_bufs[i] = skb;
458 	cp->req_count = cpu_to_le16(RX_BUFLEN);
459 	cp->command = cpu_to_le16(INPUT_LAST + INTR_ALWAYS);
460 	cp->phy_addr = cpu_to_le32(virt_to_bus(data));
461 	cp->xfer_status = 0;
462 	++cp;
463     }
464     mp->rx_bufs[i] = NULL;
465     cp->command = cpu_to_le16(DBDMA_STOP);
466     mp->rx_fill = i;
467     mp->rx_empty = 0;
468 
469     /* Put a branch back to the beginning of the receive command list */
470     ++cp;
471     cp->command = cpu_to_le16(DBDMA_NOP + BR_ALWAYS);
472     cp->cmd_dep = cpu_to_le32(virt_to_bus(mp->rx_cmds));
473 
474     /* start rx dma */
475     out_le32(&rd->control, (RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
476     out_le32(&rd->cmdptr, virt_to_bus(mp->rx_cmds));
477     out_le32(&rd->control, (RUN << 16) | RUN);
478 
479     /* put a branch at the end of the tx command list */
480     cp = mp->tx_cmds + NCMDS_TX * N_TX_RING;
481     cp->command = cpu_to_le16(DBDMA_NOP + BR_ALWAYS);
482     cp->cmd_dep = cpu_to_le32(virt_to_bus(mp->tx_cmds));
483 
484     /* reset tx dma */
485     out_le32(&td->control, (RUN|PAUSE|FLUSH|WAKE) << 16);
486     out_le32(&td->cmdptr, virt_to_bus(mp->tx_cmds));
487     mp->tx_fill = 0;
488     mp->tx_empty = 0;
489     mp->tx_fullup = 0;
490     mp->tx_active = 0;
491     mp->tx_bad_runt = 0;
492 
493     /* turn it on! */
494     out_8(&mb->maccc, mp->maccc);
495     /* enable all interrupts except receive interrupts */
496     out_8(&mb->imr, RCVINT);
497 
498     return 0;
499 }
500 
501 static int mace_close(struct net_device *dev)
502 {
503     struct mace_data *mp = netdev_priv(dev);
504     volatile struct mace __iomem *mb = mp->mace;
505     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
506     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
507 
508     /* disable rx and tx */
509     out_8(&mb->maccc, 0);
510     out_8(&mb->imr, 0xff);		/* disable all intrs */
511 
512     /* disable rx and tx dma */
513     rd->control = cpu_to_le32((RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
514     td->control = cpu_to_le32((RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
515 
516     mace_clean_rings(mp);
517 
518     return 0;
519 }
520 
521 static inline void mace_set_timeout(struct net_device *dev)
522 {
523     struct mace_data *mp = netdev_priv(dev);
524 
525     if (mp->timeout_active)
526 	del_timer(&mp->tx_timeout);
527     mp->tx_timeout.expires = jiffies + TX_TIMEOUT;
528     add_timer(&mp->tx_timeout);
529     mp->timeout_active = 1;
530 }
531 
532 static netdev_tx_t mace_xmit_start(struct sk_buff *skb, struct net_device *dev)
533 {
534     struct mace_data *mp = netdev_priv(dev);
535     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
536     volatile struct dbdma_cmd *cp, *np;
537     unsigned long flags;
538     int fill, next, len;
539 
540     /* see if there's a free slot in the tx ring */
541     spin_lock_irqsave(&mp->lock, flags);
542     fill = mp->tx_fill;
543     next = fill + 1;
544     if (next >= N_TX_RING)
545 	next = 0;
546     if (next == mp->tx_empty) {
547 	netif_stop_queue(dev);
548 	mp->tx_fullup = 1;
549 	spin_unlock_irqrestore(&mp->lock, flags);
550 	return NETDEV_TX_BUSY;		/* can't take it at the moment */
551     }
552     spin_unlock_irqrestore(&mp->lock, flags);
553 
554     /* partially fill in the dma command block */
555     len = skb->len;
556     if (len > ETH_FRAME_LEN) {
557 	printk(KERN_DEBUG "mace: xmit frame too long (%d)\n", len);
558 	len = ETH_FRAME_LEN;
559     }
560     mp->tx_bufs[fill] = skb;
561     cp = mp->tx_cmds + NCMDS_TX * fill;
562     cp->req_count = cpu_to_le16(len);
563     cp->phy_addr = cpu_to_le32(virt_to_bus(skb->data));
564 
565     np = mp->tx_cmds + NCMDS_TX * next;
566     out_le16(&np->command, DBDMA_STOP);
567 
568     /* poke the tx dma channel */
569     spin_lock_irqsave(&mp->lock, flags);
570     mp->tx_fill = next;
571     if (!mp->tx_bad_runt && mp->tx_active < MAX_TX_ACTIVE) {
572 	out_le16(&cp->xfer_status, 0);
573 	out_le16(&cp->command, OUTPUT_LAST);
574 	out_le32(&td->control, ((RUN|WAKE) << 16) + (RUN|WAKE));
575 	++mp->tx_active;
576 	mace_set_timeout(dev);
577     }
578     if (++next >= N_TX_RING)
579 	next = 0;
580     if (next == mp->tx_empty)
581 	netif_stop_queue(dev);
582     spin_unlock_irqrestore(&mp->lock, flags);
583 
584     return NETDEV_TX_OK;
585 }
586 
587 static void mace_set_multicast(struct net_device *dev)
588 {
589     struct mace_data *mp = netdev_priv(dev);
590     volatile struct mace __iomem *mb = mp->mace;
591     int i;
592     u32 crc;
593     unsigned long flags;
594 
595     spin_lock_irqsave(&mp->lock, flags);
596     mp->maccc &= ~PROM;
597     if (dev->flags & IFF_PROMISC) {
598 	mp->maccc |= PROM;
599     } else {
600 	unsigned char multicast_filter[8];
601 	struct netdev_hw_addr *ha;
602 
603 	if (dev->flags & IFF_ALLMULTI) {
604 	    for (i = 0; i < 8; i++)
605 		multicast_filter[i] = 0xff;
606 	} else {
607 	    for (i = 0; i < 8; i++)
608 		multicast_filter[i] = 0;
609 	    netdev_for_each_mc_addr(ha, dev) {
610 	        crc = ether_crc_le(6, ha->addr);
611 		i = crc >> 26;	/* bit number in multicast_filter */
612 		multicast_filter[i >> 3] |= 1 << (i & 7);
613 	    }
614 	}
615 #if 0
616 	printk("Multicast filter :");
617 	for (i = 0; i < 8; i++)
618 	    printk("%02x ", multicast_filter[i]);
619 	printk("\n");
620 #endif
621 
622 	if (mp->chipid == BROKEN_ADDRCHG_REV)
623 	    out_8(&mb->iac, LOGADDR);
624 	else {
625 	    out_8(&mb->iac, ADDRCHG | LOGADDR);
626 	    while ((in_8(&mb->iac) & ADDRCHG) != 0)
627 		;
628 	}
629 	for (i = 0; i < 8; ++i)
630 	    out_8(&mb->ladrf, multicast_filter[i]);
631 	if (mp->chipid != BROKEN_ADDRCHG_REV)
632 	    out_8(&mb->iac, 0);
633     }
634     /* reset maccc */
635     out_8(&mb->maccc, mp->maccc);
636     spin_unlock_irqrestore(&mp->lock, flags);
637 }
638 
639 static void mace_handle_misc_intrs(struct mace_data *mp, int intr, struct net_device *dev)
640 {
641     volatile struct mace __iomem *mb = mp->mace;
642     static int mace_babbles, mace_jabbers;
643 
644     if (intr & MPCO)
645 	dev->stats.rx_missed_errors += 256;
646     dev->stats.rx_missed_errors += in_8(&mb->mpc);   /* reading clears it */
647     if (intr & RNTPCO)
648 	dev->stats.rx_length_errors += 256;
649     dev->stats.rx_length_errors += in_8(&mb->rntpc); /* reading clears it */
650     if (intr & CERR)
651 	++dev->stats.tx_heartbeat_errors;
652     if (intr & BABBLE)
653 	if (mace_babbles++ < 4)
654 	    printk(KERN_DEBUG "mace: babbling transmitter\n");
655     if (intr & JABBER)
656 	if (mace_jabbers++ < 4)
657 	    printk(KERN_DEBUG "mace: jabbering transceiver\n");
658 }
659 
660 static irqreturn_t mace_interrupt(int irq, void *dev_id)
661 {
662     struct net_device *dev = (struct net_device *) dev_id;
663     struct mace_data *mp = netdev_priv(dev);
664     volatile struct mace __iomem *mb = mp->mace;
665     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
666     volatile struct dbdma_cmd *cp;
667     int intr, fs, i, stat, x;
668     int xcount, dstat;
669     unsigned long flags;
670     /* static int mace_last_fs, mace_last_xcount; */
671 
672     spin_lock_irqsave(&mp->lock, flags);
673     intr = in_8(&mb->ir);		/* read interrupt register */
674     in_8(&mb->xmtrc);			/* get retries */
675     mace_handle_misc_intrs(mp, intr, dev);
676 
677     i = mp->tx_empty;
678     while (in_8(&mb->pr) & XMTSV) {
679 	del_timer(&mp->tx_timeout);
680 	mp->timeout_active = 0;
681 	/*
682 	 * Clear any interrupt indication associated with this status
683 	 * word.  This appears to unlatch any error indication from
684 	 * the DMA controller.
685 	 */
686 	intr = in_8(&mb->ir);
687 	if (intr != 0)
688 	    mace_handle_misc_intrs(mp, intr, dev);
689 	if (mp->tx_bad_runt) {
690 	    fs = in_8(&mb->xmtfs);
691 	    mp->tx_bad_runt = 0;
692 	    out_8(&mb->xmtfc, AUTO_PAD_XMIT);
693 	    continue;
694 	}
695 	dstat = le32_to_cpu(td->status);
696 	/* stop DMA controller */
697 	out_le32(&td->control, RUN << 16);
698 	/*
699 	 * xcount is the number of complete frames which have been
700 	 * written to the fifo but for which status has not been read.
701 	 */
702 	xcount = (in_8(&mb->fifofc) >> XMTFC_SH) & XMTFC_MASK;
703 	if (xcount == 0 || (dstat & DEAD)) {
704 	    /*
705 	     * If a packet was aborted before the DMA controller has
706 	     * finished transferring it, it seems that there are 2 bytes
707 	     * which are stuck in some buffer somewhere.  These will get
708 	     * transmitted as soon as we read the frame status (which
709 	     * reenables the transmit data transfer request).  Turning
710 	     * off the DMA controller and/or resetting the MACE doesn't
711 	     * help.  So we disable auto-padding and FCS transmission
712 	     * so the two bytes will only be a runt packet which should
713 	     * be ignored by other stations.
714 	     */
715 	    out_8(&mb->xmtfc, DXMTFCS);
716 	}
717 	fs = in_8(&mb->xmtfs);
718 	if ((fs & XMTSV) == 0) {
719 	    printk(KERN_ERR "mace: xmtfs not valid! (fs=%x xc=%d ds=%x)\n",
720 		   fs, xcount, dstat);
721 	    mace_reset(dev);
722 		/*
723 		 * XXX mace likes to hang the machine after a xmtfs error.
724 		 * This is hard to reproduce, resetting *may* help
725 		 */
726 	}
727 	cp = mp->tx_cmds + NCMDS_TX * i;
728 	stat = le16_to_cpu(cp->xfer_status);
729 	if ((fs & (UFLO|LCOL|LCAR|RTRY)) || (dstat & DEAD) || xcount == 0) {
730 	    /*
731 	     * Check whether there were in fact 2 bytes written to
732 	     * the transmit FIFO.
733 	     */
734 	    udelay(1);
735 	    x = (in_8(&mb->fifofc) >> XMTFC_SH) & XMTFC_MASK;
736 	    if (x != 0) {
737 		/* there were two bytes with an end-of-packet indication */
738 		mp->tx_bad_runt = 1;
739 		mace_set_timeout(dev);
740 	    } else {
741 		/*
742 		 * Either there weren't the two bytes buffered up, or they
743 		 * didn't have an end-of-packet indication.
744 		 * We flush the transmit FIFO just in case (by setting the
745 		 * XMTFWU bit with the transmitter disabled).
746 		 */
747 		out_8(&mb->maccc, in_8(&mb->maccc) & ~ENXMT);
748 		out_8(&mb->fifocc, in_8(&mb->fifocc) | XMTFWU);
749 		udelay(1);
750 		out_8(&mb->maccc, in_8(&mb->maccc) | ENXMT);
751 		out_8(&mb->xmtfc, AUTO_PAD_XMIT);
752 	    }
753 	}
754 	/* dma should have finished */
755 	if (i == mp->tx_fill) {
756 	    printk(KERN_DEBUG "mace: tx ring ran out? (fs=%x xc=%d ds=%x)\n",
757 		   fs, xcount, dstat);
758 	    continue;
759 	}
760 	/* Update stats */
761 	if (fs & (UFLO|LCOL|LCAR|RTRY)) {
762 	    ++dev->stats.tx_errors;
763 	    if (fs & LCAR)
764 		++dev->stats.tx_carrier_errors;
765 	    if (fs & (UFLO|LCOL|RTRY))
766 		++dev->stats.tx_aborted_errors;
767 	} else {
768 	    dev->stats.tx_bytes += mp->tx_bufs[i]->len;
769 	    ++dev->stats.tx_packets;
770 	}
771 	dev_consume_skb_irq(mp->tx_bufs[i]);
772 	--mp->tx_active;
773 	if (++i >= N_TX_RING)
774 	    i = 0;
775 #if 0
776 	mace_last_fs = fs;
777 	mace_last_xcount = xcount;
778 #endif
779     }
780 
781     if (i != mp->tx_empty) {
782 	mp->tx_fullup = 0;
783 	netif_wake_queue(dev);
784     }
785     mp->tx_empty = i;
786     i += mp->tx_active;
787     if (i >= N_TX_RING)
788 	i -= N_TX_RING;
789     if (!mp->tx_bad_runt && i != mp->tx_fill && mp->tx_active < MAX_TX_ACTIVE) {
790 	do {
791 	    /* set up the next one */
792 	    cp = mp->tx_cmds + NCMDS_TX * i;
793 	    out_le16(&cp->xfer_status, 0);
794 	    out_le16(&cp->command, OUTPUT_LAST);
795 	    ++mp->tx_active;
796 	    if (++i >= N_TX_RING)
797 		i = 0;
798 	} while (i != mp->tx_fill && mp->tx_active < MAX_TX_ACTIVE);
799 	out_le32(&td->control, ((RUN|WAKE) << 16) + (RUN|WAKE));
800 	mace_set_timeout(dev);
801     }
802     spin_unlock_irqrestore(&mp->lock, flags);
803     return IRQ_HANDLED;
804 }
805 
806 static void mace_tx_timeout(struct timer_list *t)
807 {
808     struct mace_data *mp = from_timer(mp, t, tx_timeout);
809     struct net_device *dev = macio_get_drvdata(mp->mdev);
810     volatile struct mace __iomem *mb = mp->mace;
811     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
812     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
813     volatile struct dbdma_cmd *cp;
814     unsigned long flags;
815     int i;
816 
817     spin_lock_irqsave(&mp->lock, flags);
818     mp->timeout_active = 0;
819     if (mp->tx_active == 0 && !mp->tx_bad_runt)
820 	goto out;
821 
822     /* update various counters */
823     mace_handle_misc_intrs(mp, in_8(&mb->ir), dev);
824 
825     cp = mp->tx_cmds + NCMDS_TX * mp->tx_empty;
826 
827     /* turn off both tx and rx and reset the chip */
828     out_8(&mb->maccc, 0);
829     printk(KERN_ERR "mace: transmit timeout - resetting\n");
830     dbdma_reset(td);
831     mace_reset(dev);
832 
833     /* restart rx dma */
834     cp = bus_to_virt(le32_to_cpu(rd->cmdptr));
835     dbdma_reset(rd);
836     out_le16(&cp->xfer_status, 0);
837     out_le32(&rd->cmdptr, virt_to_bus(cp));
838     out_le32(&rd->control, (RUN << 16) | RUN);
839 
840     /* fix up the transmit side */
841     i = mp->tx_empty;
842     mp->tx_active = 0;
843     ++dev->stats.tx_errors;
844     if (mp->tx_bad_runt) {
845 	mp->tx_bad_runt = 0;
846     } else if (i != mp->tx_fill) {
847 	dev_kfree_skb_irq(mp->tx_bufs[i]);
848 	if (++i >= N_TX_RING)
849 	    i = 0;
850 	mp->tx_empty = i;
851     }
852     mp->tx_fullup = 0;
853     netif_wake_queue(dev);
854     if (i != mp->tx_fill) {
855 	cp = mp->tx_cmds + NCMDS_TX * i;
856 	out_le16(&cp->xfer_status, 0);
857 	out_le16(&cp->command, OUTPUT_LAST);
858 	out_le32(&td->cmdptr, virt_to_bus(cp));
859 	out_le32(&td->control, (RUN << 16) | RUN);
860 	++mp->tx_active;
861 	mace_set_timeout(dev);
862     }
863 
864     /* turn it back on */
865     out_8(&mb->imr, RCVINT);
866     out_8(&mb->maccc, mp->maccc);
867 
868 out:
869     spin_unlock_irqrestore(&mp->lock, flags);
870 }
871 
872 static irqreturn_t mace_txdma_intr(int irq, void *dev_id)
873 {
874 	return IRQ_HANDLED;
875 }
876 
877 static irqreturn_t mace_rxdma_intr(int irq, void *dev_id)
878 {
879     struct net_device *dev = (struct net_device *) dev_id;
880     struct mace_data *mp = netdev_priv(dev);
881     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
882     volatile struct dbdma_cmd *cp, *np;
883     int i, nb, stat, next;
884     struct sk_buff *skb;
885     unsigned frame_status;
886     static int mace_lost_status;
887     unsigned char *data;
888     unsigned long flags;
889 
890     spin_lock_irqsave(&mp->lock, flags);
891     for (i = mp->rx_empty; i != mp->rx_fill; ) {
892 	cp = mp->rx_cmds + i;
893 	stat = le16_to_cpu(cp->xfer_status);
894 	if ((stat & ACTIVE) == 0) {
895 	    next = i + 1;
896 	    if (next >= N_RX_RING)
897 		next = 0;
898 	    np = mp->rx_cmds + next;
899 	    if (next != mp->rx_fill &&
900 		(le16_to_cpu(np->xfer_status) & ACTIVE) != 0) {
901 		printk(KERN_DEBUG "mace: lost a status word\n");
902 		++mace_lost_status;
903 	    } else
904 		break;
905 	}
906 	nb = le16_to_cpu(cp->req_count) - le16_to_cpu(cp->res_count);
907 	out_le16(&cp->command, DBDMA_STOP);
908 	/* got a packet, have a look at it */
909 	skb = mp->rx_bufs[i];
910 	if (!skb) {
911 	    ++dev->stats.rx_dropped;
912 	} else if (nb > 8) {
913 	    data = skb->data;
914 	    frame_status = (data[nb-3] << 8) + data[nb-4];
915 	    if (frame_status & (RS_OFLO|RS_CLSN|RS_FRAMERR|RS_FCSERR)) {
916 		++dev->stats.rx_errors;
917 		if (frame_status & RS_OFLO)
918 		    ++dev->stats.rx_over_errors;
919 		if (frame_status & RS_FRAMERR)
920 		    ++dev->stats.rx_frame_errors;
921 		if (frame_status & RS_FCSERR)
922 		    ++dev->stats.rx_crc_errors;
923 	    } else {
924 		/* Mace feature AUTO_STRIP_RCV is on by default, dropping the
925 		 * FCS on frames with 802.3 headers. This means that Ethernet
926 		 * frames have 8 extra octets at the end, while 802.3 frames
927 		 * have only 4. We need to correctly account for this. */
928 		if (*(unsigned short *)(data+12) < 1536) /* 802.3 header */
929 		    nb -= 4;
930 		else	/* Ethernet header; mace includes FCS */
931 		    nb -= 8;
932 		skb_put(skb, nb);
933 		skb->protocol = eth_type_trans(skb, dev);
934 		dev->stats.rx_bytes += skb->len;
935 		netif_rx(skb);
936 		mp->rx_bufs[i] = NULL;
937 		++dev->stats.rx_packets;
938 	    }
939 	} else {
940 	    ++dev->stats.rx_errors;
941 	    ++dev->stats.rx_length_errors;
942 	}
943 
944 	/* advance to next */
945 	if (++i >= N_RX_RING)
946 	    i = 0;
947     }
948     mp->rx_empty = i;
949 
950     i = mp->rx_fill;
951     for (;;) {
952 	next = i + 1;
953 	if (next >= N_RX_RING)
954 	    next = 0;
955 	if (next == mp->rx_empty)
956 	    break;
957 	cp = mp->rx_cmds + i;
958 	skb = mp->rx_bufs[i];
959 	if (!skb) {
960 	    skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
961 	    if (skb) {
962 		skb_reserve(skb, 2);
963 		mp->rx_bufs[i] = skb;
964 	    }
965 	}
966 	cp->req_count = cpu_to_le16(RX_BUFLEN);
967 	data = skb? skb->data: dummy_buf;
968 	cp->phy_addr = cpu_to_le32(virt_to_bus(data));
969 	out_le16(&cp->xfer_status, 0);
970 	out_le16(&cp->command, INPUT_LAST + INTR_ALWAYS);
971 #if 0
972 	if ((le32_to_cpu(rd->status) & ACTIVE) != 0) {
973 	    out_le32(&rd->control, (PAUSE << 16) | PAUSE);
974 	    while ((in_le32(&rd->status) & ACTIVE) != 0)
975 		;
976 	}
977 #endif
978 	i = next;
979     }
980     if (i != mp->rx_fill) {
981 	out_le32(&rd->control, ((RUN|WAKE) << 16) | (RUN|WAKE));
982 	mp->rx_fill = i;
983     }
984     spin_unlock_irqrestore(&mp->lock, flags);
985     return IRQ_HANDLED;
986 }
987 
988 static const struct of_device_id mace_match[] =
989 {
990 	{
991 	.name 		= "mace",
992 	},
993 	{},
994 };
995 MODULE_DEVICE_TABLE (of, mace_match);
996 
997 static struct macio_driver mace_driver =
998 {
999 	.driver = {
1000 		.name 		= "mace",
1001 		.owner		= THIS_MODULE,
1002 		.of_match_table	= mace_match,
1003 	},
1004 	.probe		= mace_probe,
1005 	.remove		= mace_remove,
1006 };
1007 
1008 
1009 static int __init mace_init(void)
1010 {
1011 	return macio_register_driver(&mace_driver);
1012 }
1013 
1014 static void __exit mace_cleanup(void)
1015 {
1016 	macio_unregister_driver(&mace_driver);
1017 
1018 	kfree(dummy_buf);
1019 	dummy_buf = NULL;
1020 }
1021 
1022 MODULE_AUTHOR("Paul Mackerras");
1023 MODULE_DESCRIPTION("PowerMac MACE driver.");
1024 module_param(port_aaui, int, 0);
1025 MODULE_PARM_DESC(port_aaui, "MACE uses AAUI port (0-1)");
1026 MODULE_LICENSE("GPL");
1027 
1028 module_init(mace_init);
1029 module_exit(mace_cleanup);
1030