xref: /openbmc/linux/drivers/net/ethernet/apple/mace.c (revision 20e2fc42)
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 <asm/prom.h>
23 #include <asm/dbdma.h>
24 #include <asm/io.h>
25 #include <asm/pgtable.h>
26 #include <asm/macio.h>
27 
28 #include "mace.h"
29 
30 static int port_aaui = -1;
31 
32 #define N_RX_RING	8
33 #define N_TX_RING	6
34 #define MAX_TX_ACTIVE	1
35 #define NCMDS_TX	1	/* dma commands per element in tx ring */
36 #define RX_BUFLEN	(ETH_FRAME_LEN + 8)
37 #define TX_TIMEOUT	HZ	/* 1 second */
38 
39 /* Chip rev needs workaround on HW & multicast addr change */
40 #define BROKEN_ADDRCHG_REV	0x0941
41 
42 /* Bits in transmit DMA status */
43 #define TX_DMA_ERR	0x80
44 
45 struct mace_data {
46     volatile struct mace __iomem *mace;
47     volatile struct dbdma_regs __iomem *tx_dma;
48     int tx_dma_intr;
49     volatile struct dbdma_regs __iomem *rx_dma;
50     int rx_dma_intr;
51     volatile struct dbdma_cmd *tx_cmds;	/* xmit dma command list */
52     volatile struct dbdma_cmd *rx_cmds;	/* recv dma command list */
53     struct sk_buff *rx_bufs[N_RX_RING];
54     int rx_fill;
55     int rx_empty;
56     struct sk_buff *tx_bufs[N_TX_RING];
57     int tx_fill;
58     int tx_empty;
59     unsigned char maccc;
60     unsigned char tx_fullup;
61     unsigned char tx_active;
62     unsigned char tx_bad_runt;
63     struct timer_list tx_timeout;
64     int timeout_active;
65     int port_aaui;
66     int chipid;
67     struct macio_dev *mdev;
68     spinlock_t lock;
69 };
70 
71 /*
72  * Number of bytes of private data per MACE: allow enough for
73  * the rx and tx dma commands plus a branch dma command each,
74  * and another 16 bytes to allow us to align the dma command
75  * buffers on a 16 byte boundary.
76  */
77 #define PRIV_BYTES	(sizeof(struct mace_data) \
78 	+ (N_RX_RING + NCMDS_TX * N_TX_RING + 3) * sizeof(struct dbdma_cmd))
79 
80 static int mace_open(struct net_device *dev);
81 static int mace_close(struct net_device *dev);
82 static netdev_tx_t mace_xmit_start(struct sk_buff *skb, struct net_device *dev);
83 static void mace_set_multicast(struct net_device *dev);
84 static void mace_reset(struct net_device *dev);
85 static int mace_set_address(struct net_device *dev, void *addr);
86 static irqreturn_t mace_interrupt(int irq, void *dev_id);
87 static irqreturn_t mace_txdma_intr(int irq, void *dev_id);
88 static irqreturn_t mace_rxdma_intr(int irq, void *dev_id);
89 static void mace_set_timeout(struct net_device *dev);
90 static void mace_tx_timeout(struct timer_list *t);
91 static inline void dbdma_reset(volatile struct dbdma_regs __iomem *dma);
92 static inline void mace_clean_rings(struct mace_data *mp);
93 static void __mace_set_address(struct net_device *dev, void *addr);
94 
95 /*
96  * If we can't get a skbuff when we need it, we use this area for DMA.
97  */
98 static unsigned char *dummy_buf;
99 
100 static const struct net_device_ops mace_netdev_ops = {
101 	.ndo_open		= mace_open,
102 	.ndo_stop		= mace_close,
103 	.ndo_start_xmit		= mace_xmit_start,
104 	.ndo_set_rx_mode	= mace_set_multicast,
105 	.ndo_set_mac_address	= mace_set_address,
106 	.ndo_validate_addr	= eth_validate_addr,
107 };
108 
109 static int mace_probe(struct macio_dev *mdev, const struct of_device_id *match)
110 {
111 	struct device_node *mace = macio_get_of_node(mdev);
112 	struct net_device *dev;
113 	struct mace_data *mp;
114 	const unsigned char *addr;
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 		dev->dev_addr[j] = rev ? bitrev8(addr[j]): addr[j];
171 	}
172 	mp->chipid = (in_8(&mp->mace->chipid_hi) << 8) |
173 			in_8(&mp->mace->chipid_lo);
174 
175 
176 	mp = netdev_priv(dev);
177 	mp->maccc = ENXMT | ENRCV;
178 
179 	mp->tx_dma = ioremap(macio_resource_start(mdev, 1), 0x1000);
180 	if (mp->tx_dma == NULL) {
181 		printk(KERN_ERR "MACE: can't map TX DMA resources !\n");
182 		rc = -ENOMEM;
183 		goto err_unmap_io;
184 	}
185 	mp->tx_dma_intr = macio_irq(mdev, 1);
186 
187 	mp->rx_dma = ioremap(macio_resource_start(mdev, 2), 0x1000);
188 	if (mp->rx_dma == NULL) {
189 		printk(KERN_ERR "MACE: can't map RX DMA resources !\n");
190 		rc = -ENOMEM;
191 		goto err_unmap_tx_dma;
192 	}
193 	mp->rx_dma_intr = macio_irq(mdev, 2);
194 
195 	mp->tx_cmds = (volatile struct dbdma_cmd *) DBDMA_ALIGN(mp + 1);
196 	mp->rx_cmds = mp->tx_cmds + NCMDS_TX * N_TX_RING + 1;
197 
198 	memset((char *) mp->tx_cmds, 0,
199 	       (NCMDS_TX*N_TX_RING + N_RX_RING + 2) * sizeof(struct dbdma_cmd));
200 	timer_setup(&mp->tx_timeout, mace_tx_timeout, 0);
201 	spin_lock_init(&mp->lock);
202 	mp->timeout_active = 0;
203 
204 	if (port_aaui >= 0)
205 		mp->port_aaui = port_aaui;
206 	else {
207 		/* Apple Network Server uses the AAUI port */
208 		if (of_machine_is_compatible("AAPL,ShinerESB"))
209 			mp->port_aaui = 1;
210 		else {
211 #ifdef CONFIG_MACE_AAUI_PORT
212 			mp->port_aaui = 1;
213 #else
214 			mp->port_aaui = 0;
215 #endif
216 		}
217 	}
218 
219 	dev->netdev_ops = &mace_netdev_ops;
220 
221 	/*
222 	 * Most of what is below could be moved to mace_open()
223 	 */
224 	mace_reset(dev);
225 
226 	rc = request_irq(dev->irq, mace_interrupt, 0, "MACE", dev);
227 	if (rc) {
228 		printk(KERN_ERR "MACE: can't get irq %d\n", dev->irq);
229 		goto err_unmap_rx_dma;
230 	}
231 	rc = request_irq(mp->tx_dma_intr, mace_txdma_intr, 0, "MACE-txdma", dev);
232 	if (rc) {
233 		printk(KERN_ERR "MACE: can't get irq %d\n", mp->tx_dma_intr);
234 		goto err_free_irq;
235 	}
236 	rc = request_irq(mp->rx_dma_intr, mace_rxdma_intr, 0, "MACE-rxdma", dev);
237 	if (rc) {
238 		printk(KERN_ERR "MACE: can't get irq %d\n", mp->rx_dma_intr);
239 		goto err_free_tx_irq;
240 	}
241 
242 	rc = register_netdev(dev);
243 	if (rc) {
244 		printk(KERN_ERR "MACE: Cannot register net device, aborting.\n");
245 		goto err_free_rx_irq;
246 	}
247 
248 	printk(KERN_INFO "%s: MACE at %pM, chip revision %d.%d\n",
249 	       dev->name, dev->dev_addr,
250 	       mp->chipid >> 8, mp->chipid & 0xff);
251 
252 	return 0;
253 
254  err_free_rx_irq:
255 	free_irq(macio_irq(mdev, 2), dev);
256  err_free_tx_irq:
257 	free_irq(macio_irq(mdev, 1), dev);
258  err_free_irq:
259 	free_irq(macio_irq(mdev, 0), dev);
260  err_unmap_rx_dma:
261 	iounmap(mp->rx_dma);
262  err_unmap_tx_dma:
263 	iounmap(mp->tx_dma);
264  err_unmap_io:
265 	iounmap(mp->mace);
266  err_free:
267 	free_netdev(dev);
268  err_release:
269 	macio_release_resources(mdev);
270 
271 	return rc;
272 }
273 
274 static int mace_remove(struct macio_dev *mdev)
275 {
276 	struct net_device *dev = macio_get_drvdata(mdev);
277 	struct mace_data *mp;
278 
279 	BUG_ON(dev == NULL);
280 
281 	macio_set_drvdata(mdev, NULL);
282 
283 	mp = netdev_priv(dev);
284 
285 	unregister_netdev(dev);
286 
287 	free_irq(dev->irq, dev);
288 	free_irq(mp->tx_dma_intr, dev);
289 	free_irq(mp->rx_dma_intr, dev);
290 
291 	iounmap(mp->rx_dma);
292 	iounmap(mp->tx_dma);
293 	iounmap(mp->mace);
294 
295 	free_netdev(dev);
296 
297 	macio_release_resources(mdev);
298 
299 	return 0;
300 }
301 
302 static void dbdma_reset(volatile struct dbdma_regs __iomem *dma)
303 {
304     int i;
305 
306     out_le32(&dma->control, (WAKE|FLUSH|PAUSE|RUN) << 16);
307 
308     /*
309      * Yes this looks peculiar, but apparently it needs to be this
310      * way on some machines.
311      */
312     for (i = 200; i > 0; --i)
313 	if (le32_to_cpu(dma->control) & RUN)
314 	    udelay(1);
315 }
316 
317 static void mace_reset(struct net_device *dev)
318 {
319     struct mace_data *mp = netdev_priv(dev);
320     volatile struct mace __iomem *mb = mp->mace;
321     int i;
322 
323     /* soft-reset the chip */
324     i = 200;
325     while (--i) {
326 	out_8(&mb->biucc, SWRST);
327 	if (in_8(&mb->biucc) & SWRST) {
328 	    udelay(10);
329 	    continue;
330 	}
331 	break;
332     }
333     if (!i) {
334 	printk(KERN_ERR "mace: cannot reset chip!\n");
335 	return;
336     }
337 
338     out_8(&mb->imr, 0xff);	/* disable all intrs for now */
339     i = in_8(&mb->ir);
340     out_8(&mb->maccc, 0);	/* turn off tx, rx */
341 
342     out_8(&mb->biucc, XMTSP_64);
343     out_8(&mb->utr, RTRD);
344     out_8(&mb->fifocc, RCVFW_32 | XMTFW_16 | XMTFWU | RCVFWU | XMTBRST);
345     out_8(&mb->xmtfc, AUTO_PAD_XMIT); /* auto-pad short frames */
346     out_8(&mb->rcvfc, 0);
347 
348     /* load up the hardware address */
349     __mace_set_address(dev, dev->dev_addr);
350 
351     /* clear the multicast filter */
352     if (mp->chipid == BROKEN_ADDRCHG_REV)
353 	out_8(&mb->iac, LOGADDR);
354     else {
355 	out_8(&mb->iac, ADDRCHG | LOGADDR);
356 	while ((in_8(&mb->iac) & ADDRCHG) != 0)
357 		;
358     }
359     for (i = 0; i < 8; ++i)
360 	out_8(&mb->ladrf, 0);
361 
362     /* done changing address */
363     if (mp->chipid != BROKEN_ADDRCHG_REV)
364 	out_8(&mb->iac, 0);
365 
366     if (mp->port_aaui)
367     	out_8(&mb->plscc, PORTSEL_AUI + ENPLSIO);
368     else
369     	out_8(&mb->plscc, PORTSEL_GPSI + ENPLSIO);
370 }
371 
372 static void __mace_set_address(struct net_device *dev, void *addr)
373 {
374     struct mace_data *mp = netdev_priv(dev);
375     volatile struct mace __iomem *mb = mp->mace;
376     unsigned char *p = addr;
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, dev->dev_addr[i] = p[i]);
389     if (mp->chipid != BROKEN_ADDRCHG_REV)
390         out_8(&mb->iac, 0);
391 }
392 
393 static int mace_set_address(struct net_device *dev, void *addr)
394 {
395     struct mace_data *mp = netdev_priv(dev);
396     volatile struct mace __iomem *mb = mp->mace;
397     unsigned long flags;
398 
399     spin_lock_irqsave(&mp->lock, flags);
400 
401     __mace_set_address(dev, addr);
402 
403     /* note: setting ADDRCHG clears ENRCV */
404     out_8(&mb->maccc, mp->maccc);
405 
406     spin_unlock_irqrestore(&mp->lock, flags);
407     return 0;
408 }
409 
410 static inline void mace_clean_rings(struct mace_data *mp)
411 {
412     int i;
413 
414     /* free some skb's */
415     for (i = 0; i < N_RX_RING; ++i) {
416 	if (mp->rx_bufs[i] != NULL) {
417 	    dev_kfree_skb(mp->rx_bufs[i]);
418 	    mp->rx_bufs[i] = NULL;
419 	}
420     }
421     for (i = mp->tx_empty; i != mp->tx_fill; ) {
422 	dev_kfree_skb(mp->tx_bufs[i]);
423 	if (++i >= N_TX_RING)
424 	    i = 0;
425     }
426 }
427 
428 static int mace_open(struct net_device *dev)
429 {
430     struct mace_data *mp = netdev_priv(dev);
431     volatile struct mace __iomem *mb = mp->mace;
432     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
433     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
434     volatile struct dbdma_cmd *cp;
435     int i;
436     struct sk_buff *skb;
437     unsigned char *data;
438 
439     /* reset the chip */
440     mace_reset(dev);
441 
442     /* initialize list of sk_buffs for receiving and set up recv dma */
443     mace_clean_rings(mp);
444     memset((char *)mp->rx_cmds, 0, N_RX_RING * sizeof(struct dbdma_cmd));
445     cp = mp->rx_cmds;
446     for (i = 0; i < N_RX_RING - 1; ++i) {
447 	skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
448 	if (!skb) {
449 	    data = dummy_buf;
450 	} else {
451 	    skb_reserve(skb, 2);	/* so IP header lands on 4-byte bdry */
452 	    data = skb->data;
453 	}
454 	mp->rx_bufs[i] = skb;
455 	cp->req_count = cpu_to_le16(RX_BUFLEN);
456 	cp->command = cpu_to_le16(INPUT_LAST + INTR_ALWAYS);
457 	cp->phy_addr = cpu_to_le32(virt_to_bus(data));
458 	cp->xfer_status = 0;
459 	++cp;
460     }
461     mp->rx_bufs[i] = NULL;
462     cp->command = cpu_to_le16(DBDMA_STOP);
463     mp->rx_fill = i;
464     mp->rx_empty = 0;
465 
466     /* Put a branch back to the beginning of the receive command list */
467     ++cp;
468     cp->command = cpu_to_le16(DBDMA_NOP + BR_ALWAYS);
469     cp->cmd_dep = cpu_to_le32(virt_to_bus(mp->rx_cmds));
470 
471     /* start rx dma */
472     out_le32(&rd->control, (RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
473     out_le32(&rd->cmdptr, virt_to_bus(mp->rx_cmds));
474     out_le32(&rd->control, (RUN << 16) | RUN);
475 
476     /* put a branch at the end of the tx command list */
477     cp = mp->tx_cmds + NCMDS_TX * N_TX_RING;
478     cp->command = cpu_to_le16(DBDMA_NOP + BR_ALWAYS);
479     cp->cmd_dep = cpu_to_le32(virt_to_bus(mp->tx_cmds));
480 
481     /* reset tx dma */
482     out_le32(&td->control, (RUN|PAUSE|FLUSH|WAKE) << 16);
483     out_le32(&td->cmdptr, virt_to_bus(mp->tx_cmds));
484     mp->tx_fill = 0;
485     mp->tx_empty = 0;
486     mp->tx_fullup = 0;
487     mp->tx_active = 0;
488     mp->tx_bad_runt = 0;
489 
490     /* turn it on! */
491     out_8(&mb->maccc, mp->maccc);
492     /* enable all interrupts except receive interrupts */
493     out_8(&mb->imr, RCVINT);
494 
495     return 0;
496 }
497 
498 static int mace_close(struct net_device *dev)
499 {
500     struct mace_data *mp = netdev_priv(dev);
501     volatile struct mace __iomem *mb = mp->mace;
502     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
503     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
504 
505     /* disable rx and tx */
506     out_8(&mb->maccc, 0);
507     out_8(&mb->imr, 0xff);		/* disable all intrs */
508 
509     /* disable rx and tx dma */
510     rd->control = cpu_to_le32((RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
511     td->control = cpu_to_le32((RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
512 
513     mace_clean_rings(mp);
514 
515     return 0;
516 }
517 
518 static inline void mace_set_timeout(struct net_device *dev)
519 {
520     struct mace_data *mp = netdev_priv(dev);
521 
522     if (mp->timeout_active)
523 	del_timer(&mp->tx_timeout);
524     mp->tx_timeout.expires = jiffies + TX_TIMEOUT;
525     add_timer(&mp->tx_timeout);
526     mp->timeout_active = 1;
527 }
528 
529 static netdev_tx_t mace_xmit_start(struct sk_buff *skb, struct net_device *dev)
530 {
531     struct mace_data *mp = netdev_priv(dev);
532     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
533     volatile struct dbdma_cmd *cp, *np;
534     unsigned long flags;
535     int fill, next, len;
536 
537     /* see if there's a free slot in the tx ring */
538     spin_lock_irqsave(&mp->lock, flags);
539     fill = mp->tx_fill;
540     next = fill + 1;
541     if (next >= N_TX_RING)
542 	next = 0;
543     if (next == mp->tx_empty) {
544 	netif_stop_queue(dev);
545 	mp->tx_fullup = 1;
546 	spin_unlock_irqrestore(&mp->lock, flags);
547 	return NETDEV_TX_BUSY;		/* can't take it at the moment */
548     }
549     spin_unlock_irqrestore(&mp->lock, flags);
550 
551     /* partially fill in the dma command block */
552     len = skb->len;
553     if (len > ETH_FRAME_LEN) {
554 	printk(KERN_DEBUG "mace: xmit frame too long (%d)\n", len);
555 	len = ETH_FRAME_LEN;
556     }
557     mp->tx_bufs[fill] = skb;
558     cp = mp->tx_cmds + NCMDS_TX * fill;
559     cp->req_count = cpu_to_le16(len);
560     cp->phy_addr = cpu_to_le32(virt_to_bus(skb->data));
561 
562     np = mp->tx_cmds + NCMDS_TX * next;
563     out_le16(&np->command, DBDMA_STOP);
564 
565     /* poke the tx dma channel */
566     spin_lock_irqsave(&mp->lock, flags);
567     mp->tx_fill = next;
568     if (!mp->tx_bad_runt && mp->tx_active < MAX_TX_ACTIVE) {
569 	out_le16(&cp->xfer_status, 0);
570 	out_le16(&cp->command, OUTPUT_LAST);
571 	out_le32(&td->control, ((RUN|WAKE) << 16) + (RUN|WAKE));
572 	++mp->tx_active;
573 	mace_set_timeout(dev);
574     }
575     if (++next >= N_TX_RING)
576 	next = 0;
577     if (next == mp->tx_empty)
578 	netif_stop_queue(dev);
579     spin_unlock_irqrestore(&mp->lock, flags);
580 
581     return NETDEV_TX_OK;
582 }
583 
584 static void mace_set_multicast(struct net_device *dev)
585 {
586     struct mace_data *mp = netdev_priv(dev);
587     volatile struct mace __iomem *mb = mp->mace;
588     int i;
589     u32 crc;
590     unsigned long flags;
591 
592     spin_lock_irqsave(&mp->lock, flags);
593     mp->maccc &= ~PROM;
594     if (dev->flags & IFF_PROMISC) {
595 	mp->maccc |= PROM;
596     } else {
597 	unsigned char multicast_filter[8];
598 	struct netdev_hw_addr *ha;
599 
600 	if (dev->flags & IFF_ALLMULTI) {
601 	    for (i = 0; i < 8; i++)
602 		multicast_filter[i] = 0xff;
603 	} else {
604 	    for (i = 0; i < 8; i++)
605 		multicast_filter[i] = 0;
606 	    netdev_for_each_mc_addr(ha, dev) {
607 	        crc = ether_crc_le(6, ha->addr);
608 		i = crc >> 26;	/* bit number in multicast_filter */
609 		multicast_filter[i >> 3] |= 1 << (i & 7);
610 	    }
611 	}
612 #if 0
613 	printk("Multicast filter :");
614 	for (i = 0; i < 8; i++)
615 	    printk("%02x ", multicast_filter[i]);
616 	printk("\n");
617 #endif
618 
619 	if (mp->chipid == BROKEN_ADDRCHG_REV)
620 	    out_8(&mb->iac, LOGADDR);
621 	else {
622 	    out_8(&mb->iac, ADDRCHG | LOGADDR);
623 	    while ((in_8(&mb->iac) & ADDRCHG) != 0)
624 		;
625 	}
626 	for (i = 0; i < 8; ++i)
627 	    out_8(&mb->ladrf, multicast_filter[i]);
628 	if (mp->chipid != BROKEN_ADDRCHG_REV)
629 	    out_8(&mb->iac, 0);
630     }
631     /* reset maccc */
632     out_8(&mb->maccc, mp->maccc);
633     spin_unlock_irqrestore(&mp->lock, flags);
634 }
635 
636 static void mace_handle_misc_intrs(struct mace_data *mp, int intr, struct net_device *dev)
637 {
638     volatile struct mace __iomem *mb = mp->mace;
639     static int mace_babbles, mace_jabbers;
640 
641     if (intr & MPCO)
642 	dev->stats.rx_missed_errors += 256;
643     dev->stats.rx_missed_errors += in_8(&mb->mpc);   /* reading clears it */
644     if (intr & RNTPCO)
645 	dev->stats.rx_length_errors += 256;
646     dev->stats.rx_length_errors += in_8(&mb->rntpc); /* reading clears it */
647     if (intr & CERR)
648 	++dev->stats.tx_heartbeat_errors;
649     if (intr & BABBLE)
650 	if (mace_babbles++ < 4)
651 	    printk(KERN_DEBUG "mace: babbling transmitter\n");
652     if (intr & JABBER)
653 	if (mace_jabbers++ < 4)
654 	    printk(KERN_DEBUG "mace: jabbering transceiver\n");
655 }
656 
657 static irqreturn_t mace_interrupt(int irq, void *dev_id)
658 {
659     struct net_device *dev = (struct net_device *) dev_id;
660     struct mace_data *mp = netdev_priv(dev);
661     volatile struct mace __iomem *mb = mp->mace;
662     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
663     volatile struct dbdma_cmd *cp;
664     int intr, fs, i, stat, x;
665     int xcount, dstat;
666     unsigned long flags;
667     /* static int mace_last_fs, mace_last_xcount; */
668 
669     spin_lock_irqsave(&mp->lock, flags);
670     intr = in_8(&mb->ir);		/* read interrupt register */
671     in_8(&mb->xmtrc);			/* get retries */
672     mace_handle_misc_intrs(mp, intr, dev);
673 
674     i = mp->tx_empty;
675     while (in_8(&mb->pr) & XMTSV) {
676 	del_timer(&mp->tx_timeout);
677 	mp->timeout_active = 0;
678 	/*
679 	 * Clear any interrupt indication associated with this status
680 	 * word.  This appears to unlatch any error indication from
681 	 * the DMA controller.
682 	 */
683 	intr = in_8(&mb->ir);
684 	if (intr != 0)
685 	    mace_handle_misc_intrs(mp, intr, dev);
686 	if (mp->tx_bad_runt) {
687 	    fs = in_8(&mb->xmtfs);
688 	    mp->tx_bad_runt = 0;
689 	    out_8(&mb->xmtfc, AUTO_PAD_XMIT);
690 	    continue;
691 	}
692 	dstat = le32_to_cpu(td->status);
693 	/* stop DMA controller */
694 	out_le32(&td->control, RUN << 16);
695 	/*
696 	 * xcount is the number of complete frames which have been
697 	 * written to the fifo but for which status has not been read.
698 	 */
699 	xcount = (in_8(&mb->fifofc) >> XMTFC_SH) & XMTFC_MASK;
700 	if (xcount == 0 || (dstat & DEAD)) {
701 	    /*
702 	     * If a packet was aborted before the DMA controller has
703 	     * finished transferring it, it seems that there are 2 bytes
704 	     * which are stuck in some buffer somewhere.  These will get
705 	     * transmitted as soon as we read the frame status (which
706 	     * reenables the transmit data transfer request).  Turning
707 	     * off the DMA controller and/or resetting the MACE doesn't
708 	     * help.  So we disable auto-padding and FCS transmission
709 	     * so the two bytes will only be a runt packet which should
710 	     * be ignored by other stations.
711 	     */
712 	    out_8(&mb->xmtfc, DXMTFCS);
713 	}
714 	fs = in_8(&mb->xmtfs);
715 	if ((fs & XMTSV) == 0) {
716 	    printk(KERN_ERR "mace: xmtfs not valid! (fs=%x xc=%d ds=%x)\n",
717 		   fs, xcount, dstat);
718 	    mace_reset(dev);
719 		/*
720 		 * XXX mace likes to hang the machine after a xmtfs error.
721 		 * This is hard to reproduce, resetting *may* help
722 		 */
723 	}
724 	cp = mp->tx_cmds + NCMDS_TX * i;
725 	stat = le16_to_cpu(cp->xfer_status);
726 	if ((fs & (UFLO|LCOL|LCAR|RTRY)) || (dstat & DEAD) || xcount == 0) {
727 	    /*
728 	     * Check whether there were in fact 2 bytes written to
729 	     * the transmit FIFO.
730 	     */
731 	    udelay(1);
732 	    x = (in_8(&mb->fifofc) >> XMTFC_SH) & XMTFC_MASK;
733 	    if (x != 0) {
734 		/* there were two bytes with an end-of-packet indication */
735 		mp->tx_bad_runt = 1;
736 		mace_set_timeout(dev);
737 	    } else {
738 		/*
739 		 * Either there weren't the two bytes buffered up, or they
740 		 * didn't have an end-of-packet indication.
741 		 * We flush the transmit FIFO just in case (by setting the
742 		 * XMTFWU bit with the transmitter disabled).
743 		 */
744 		out_8(&mb->maccc, in_8(&mb->maccc) & ~ENXMT);
745 		out_8(&mb->fifocc, in_8(&mb->fifocc) | XMTFWU);
746 		udelay(1);
747 		out_8(&mb->maccc, in_8(&mb->maccc) | ENXMT);
748 		out_8(&mb->xmtfc, AUTO_PAD_XMIT);
749 	    }
750 	}
751 	/* dma should have finished */
752 	if (i == mp->tx_fill) {
753 	    printk(KERN_DEBUG "mace: tx ring ran out? (fs=%x xc=%d ds=%x)\n",
754 		   fs, xcount, dstat);
755 	    continue;
756 	}
757 	/* Update stats */
758 	if (fs & (UFLO|LCOL|LCAR|RTRY)) {
759 	    ++dev->stats.tx_errors;
760 	    if (fs & LCAR)
761 		++dev->stats.tx_carrier_errors;
762 	    if (fs & (UFLO|LCOL|RTRY))
763 		++dev->stats.tx_aborted_errors;
764 	} else {
765 	    dev->stats.tx_bytes += mp->tx_bufs[i]->len;
766 	    ++dev->stats.tx_packets;
767 	}
768 	dev_consume_skb_irq(mp->tx_bufs[i]);
769 	--mp->tx_active;
770 	if (++i >= N_TX_RING)
771 	    i = 0;
772 #if 0
773 	mace_last_fs = fs;
774 	mace_last_xcount = xcount;
775 #endif
776     }
777 
778     if (i != mp->tx_empty) {
779 	mp->tx_fullup = 0;
780 	netif_wake_queue(dev);
781     }
782     mp->tx_empty = i;
783     i += mp->tx_active;
784     if (i >= N_TX_RING)
785 	i -= N_TX_RING;
786     if (!mp->tx_bad_runt && i != mp->tx_fill && mp->tx_active < MAX_TX_ACTIVE) {
787 	do {
788 	    /* set up the next one */
789 	    cp = mp->tx_cmds + NCMDS_TX * i;
790 	    out_le16(&cp->xfer_status, 0);
791 	    out_le16(&cp->command, OUTPUT_LAST);
792 	    ++mp->tx_active;
793 	    if (++i >= N_TX_RING)
794 		i = 0;
795 	} while (i != mp->tx_fill && mp->tx_active < MAX_TX_ACTIVE);
796 	out_le32(&td->control, ((RUN|WAKE) << 16) + (RUN|WAKE));
797 	mace_set_timeout(dev);
798     }
799     spin_unlock_irqrestore(&mp->lock, flags);
800     return IRQ_HANDLED;
801 }
802 
803 static void mace_tx_timeout(struct timer_list *t)
804 {
805     struct mace_data *mp = from_timer(mp, t, tx_timeout);
806     struct net_device *dev = macio_get_drvdata(mp->mdev);
807     volatile struct mace __iomem *mb = mp->mace;
808     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
809     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
810     volatile struct dbdma_cmd *cp;
811     unsigned long flags;
812     int i;
813 
814     spin_lock_irqsave(&mp->lock, flags);
815     mp->timeout_active = 0;
816     if (mp->tx_active == 0 && !mp->tx_bad_runt)
817 	goto out;
818 
819     /* update various counters */
820     mace_handle_misc_intrs(mp, in_8(&mb->ir), dev);
821 
822     cp = mp->tx_cmds + NCMDS_TX * mp->tx_empty;
823 
824     /* turn off both tx and rx and reset the chip */
825     out_8(&mb->maccc, 0);
826     printk(KERN_ERR "mace: transmit timeout - resetting\n");
827     dbdma_reset(td);
828     mace_reset(dev);
829 
830     /* restart rx dma */
831     cp = bus_to_virt(le32_to_cpu(rd->cmdptr));
832     dbdma_reset(rd);
833     out_le16(&cp->xfer_status, 0);
834     out_le32(&rd->cmdptr, virt_to_bus(cp));
835     out_le32(&rd->control, (RUN << 16) | RUN);
836 
837     /* fix up the transmit side */
838     i = mp->tx_empty;
839     mp->tx_active = 0;
840     ++dev->stats.tx_errors;
841     if (mp->tx_bad_runt) {
842 	mp->tx_bad_runt = 0;
843     } else if (i != mp->tx_fill) {
844 	dev_kfree_skb(mp->tx_bufs[i]);
845 	if (++i >= N_TX_RING)
846 	    i = 0;
847 	mp->tx_empty = i;
848     }
849     mp->tx_fullup = 0;
850     netif_wake_queue(dev);
851     if (i != mp->tx_fill) {
852 	cp = mp->tx_cmds + NCMDS_TX * i;
853 	out_le16(&cp->xfer_status, 0);
854 	out_le16(&cp->command, OUTPUT_LAST);
855 	out_le32(&td->cmdptr, virt_to_bus(cp));
856 	out_le32(&td->control, (RUN << 16) | RUN);
857 	++mp->tx_active;
858 	mace_set_timeout(dev);
859     }
860 
861     /* turn it back on */
862     out_8(&mb->imr, RCVINT);
863     out_8(&mb->maccc, mp->maccc);
864 
865 out:
866     spin_unlock_irqrestore(&mp->lock, flags);
867 }
868 
869 static irqreturn_t mace_txdma_intr(int irq, void *dev_id)
870 {
871 	return IRQ_HANDLED;
872 }
873 
874 static irqreturn_t mace_rxdma_intr(int irq, void *dev_id)
875 {
876     struct net_device *dev = (struct net_device *) dev_id;
877     struct mace_data *mp = netdev_priv(dev);
878     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
879     volatile struct dbdma_cmd *cp, *np;
880     int i, nb, stat, next;
881     struct sk_buff *skb;
882     unsigned frame_status;
883     static int mace_lost_status;
884     unsigned char *data;
885     unsigned long flags;
886 
887     spin_lock_irqsave(&mp->lock, flags);
888     for (i = mp->rx_empty; i != mp->rx_fill; ) {
889 	cp = mp->rx_cmds + i;
890 	stat = le16_to_cpu(cp->xfer_status);
891 	if ((stat & ACTIVE) == 0) {
892 	    next = i + 1;
893 	    if (next >= N_RX_RING)
894 		next = 0;
895 	    np = mp->rx_cmds + next;
896 	    if (next != mp->rx_fill &&
897 		(le16_to_cpu(np->xfer_status) & ACTIVE) != 0) {
898 		printk(KERN_DEBUG "mace: lost a status word\n");
899 		++mace_lost_status;
900 	    } else
901 		break;
902 	}
903 	nb = le16_to_cpu(cp->req_count) - le16_to_cpu(cp->res_count);
904 	out_le16(&cp->command, DBDMA_STOP);
905 	/* got a packet, have a look at it */
906 	skb = mp->rx_bufs[i];
907 	if (!skb) {
908 	    ++dev->stats.rx_dropped;
909 	} else if (nb > 8) {
910 	    data = skb->data;
911 	    frame_status = (data[nb-3] << 8) + data[nb-4];
912 	    if (frame_status & (RS_OFLO|RS_CLSN|RS_FRAMERR|RS_FCSERR)) {
913 		++dev->stats.rx_errors;
914 		if (frame_status & RS_OFLO)
915 		    ++dev->stats.rx_over_errors;
916 		if (frame_status & RS_FRAMERR)
917 		    ++dev->stats.rx_frame_errors;
918 		if (frame_status & RS_FCSERR)
919 		    ++dev->stats.rx_crc_errors;
920 	    } else {
921 		/* Mace feature AUTO_STRIP_RCV is on by default, dropping the
922 		 * FCS on frames with 802.3 headers. This means that Ethernet
923 		 * frames have 8 extra octets at the end, while 802.3 frames
924 		 * have only 4. We need to correctly account for this. */
925 		if (*(unsigned short *)(data+12) < 1536) /* 802.3 header */
926 		    nb -= 4;
927 		else	/* Ethernet header; mace includes FCS */
928 		    nb -= 8;
929 		skb_put(skb, nb);
930 		skb->protocol = eth_type_trans(skb, dev);
931 		dev->stats.rx_bytes += skb->len;
932 		netif_rx(skb);
933 		mp->rx_bufs[i] = NULL;
934 		++dev->stats.rx_packets;
935 	    }
936 	} else {
937 	    ++dev->stats.rx_errors;
938 	    ++dev->stats.rx_length_errors;
939 	}
940 
941 	/* advance to next */
942 	if (++i >= N_RX_RING)
943 	    i = 0;
944     }
945     mp->rx_empty = i;
946 
947     i = mp->rx_fill;
948     for (;;) {
949 	next = i + 1;
950 	if (next >= N_RX_RING)
951 	    next = 0;
952 	if (next == mp->rx_empty)
953 	    break;
954 	cp = mp->rx_cmds + i;
955 	skb = mp->rx_bufs[i];
956 	if (!skb) {
957 	    skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
958 	    if (skb) {
959 		skb_reserve(skb, 2);
960 		mp->rx_bufs[i] = skb;
961 	    }
962 	}
963 	cp->req_count = cpu_to_le16(RX_BUFLEN);
964 	data = skb? skb->data: dummy_buf;
965 	cp->phy_addr = cpu_to_le32(virt_to_bus(data));
966 	out_le16(&cp->xfer_status, 0);
967 	out_le16(&cp->command, INPUT_LAST + INTR_ALWAYS);
968 #if 0
969 	if ((le32_to_cpu(rd->status) & ACTIVE) != 0) {
970 	    out_le32(&rd->control, (PAUSE << 16) | PAUSE);
971 	    while ((in_le32(&rd->status) & ACTIVE) != 0)
972 		;
973 	}
974 #endif
975 	i = next;
976     }
977     if (i != mp->rx_fill) {
978 	out_le32(&rd->control, ((RUN|WAKE) << 16) | (RUN|WAKE));
979 	mp->rx_fill = i;
980     }
981     spin_unlock_irqrestore(&mp->lock, flags);
982     return IRQ_HANDLED;
983 }
984 
985 static const struct of_device_id mace_match[] =
986 {
987 	{
988 	.name 		= "mace",
989 	},
990 	{},
991 };
992 MODULE_DEVICE_TABLE (of, mace_match);
993 
994 static struct macio_driver mace_driver =
995 {
996 	.driver = {
997 		.name 		= "mace",
998 		.owner		= THIS_MODULE,
999 		.of_match_table	= mace_match,
1000 	},
1001 	.probe		= mace_probe,
1002 	.remove		= mace_remove,
1003 };
1004 
1005 
1006 static int __init mace_init(void)
1007 {
1008 	return macio_register_driver(&mace_driver);
1009 }
1010 
1011 static void __exit mace_cleanup(void)
1012 {
1013 	macio_unregister_driver(&mace_driver);
1014 
1015 	kfree(dummy_buf);
1016 	dummy_buf = NULL;
1017 }
1018 
1019 MODULE_AUTHOR("Paul Mackerras");
1020 MODULE_DESCRIPTION("PowerMac MACE driver.");
1021 module_param(port_aaui, int, 0);
1022 MODULE_PARM_DESC(port_aaui, "MACE uses AAUI port (0-1)");
1023 MODULE_LICENSE("GPL");
1024 
1025 module_init(mace_init);
1026 module_exit(mace_cleanup);
1027