xref: /openbmc/linux/drivers/net/ethernet/apple/mace.c (revision c9929f0e)
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 int 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 	return 0;
301 }
302 
303 static void dbdma_reset(volatile struct dbdma_regs __iomem *dma)
304 {
305     int i;
306 
307     out_le32(&dma->control, (WAKE|FLUSH|PAUSE|RUN) << 16);
308 
309     /*
310      * Yes this looks peculiar, but apparently it needs to be this
311      * way on some machines.
312      */
313     for (i = 200; i > 0; --i)
314 	if (le32_to_cpu(dma->control) & RUN)
315 	    udelay(1);
316 }
317 
318 static void mace_reset(struct net_device *dev)
319 {
320     struct mace_data *mp = netdev_priv(dev);
321     volatile struct mace __iomem *mb = mp->mace;
322     int i;
323 
324     /* soft-reset the chip */
325     i = 200;
326     while (--i) {
327 	out_8(&mb->biucc, SWRST);
328 	if (in_8(&mb->biucc) & SWRST) {
329 	    udelay(10);
330 	    continue;
331 	}
332 	break;
333     }
334     if (!i) {
335 	printk(KERN_ERR "mace: cannot reset chip!\n");
336 	return;
337     }
338 
339     out_8(&mb->imr, 0xff);	/* disable all intrs for now */
340     i = in_8(&mb->ir);
341     out_8(&mb->maccc, 0);	/* turn off tx, rx */
342 
343     out_8(&mb->biucc, XMTSP_64);
344     out_8(&mb->utr, RTRD);
345     out_8(&mb->fifocc, RCVFW_32 | XMTFW_16 | XMTFWU | RCVFWU | XMTBRST);
346     out_8(&mb->xmtfc, AUTO_PAD_XMIT); /* auto-pad short frames */
347     out_8(&mb->rcvfc, 0);
348 
349     /* load up the hardware address */
350     __mace_set_address(dev, dev->dev_addr);
351 
352     /* clear the multicast filter */
353     if (mp->chipid == BROKEN_ADDRCHG_REV)
354 	out_8(&mb->iac, LOGADDR);
355     else {
356 	out_8(&mb->iac, ADDRCHG | LOGADDR);
357 	while ((in_8(&mb->iac) & ADDRCHG) != 0)
358 		;
359     }
360     for (i = 0; i < 8; ++i)
361 	out_8(&mb->ladrf, 0);
362 
363     /* done changing address */
364     if (mp->chipid != BROKEN_ADDRCHG_REV)
365 	out_8(&mb->iac, 0);
366 
367     if (mp->port_aaui)
368 	out_8(&mb->plscc, PORTSEL_AUI + ENPLSIO);
369     else
370 	out_8(&mb->plscc, PORTSEL_GPSI + ENPLSIO);
371 }
372 
373 static void __mace_set_address(struct net_device *dev, const void *addr)
374 {
375     struct mace_data *mp = netdev_priv(dev);
376     volatile struct mace __iomem *mb = mp->mace;
377     const unsigned char *p = addr;
378     u8 macaddr[ETH_ALEN];
379     int i;
380 
381     /* load up the hardware address */
382     if (mp->chipid == BROKEN_ADDRCHG_REV)
383 	out_8(&mb->iac, PHYADDR);
384     else {
385 	out_8(&mb->iac, ADDRCHG | PHYADDR);
386 	while ((in_8(&mb->iac) & ADDRCHG) != 0)
387 	    ;
388     }
389     for (i = 0; i < 6; ++i)
390         out_8(&mb->padr, macaddr[i] = p[i]);
391 
392     eth_hw_addr_set(dev, macaddr);
393 
394     if (mp->chipid != BROKEN_ADDRCHG_REV)
395         out_8(&mb->iac, 0);
396 }
397 
398 static int mace_set_address(struct net_device *dev, void *addr)
399 {
400     struct mace_data *mp = netdev_priv(dev);
401     volatile struct mace __iomem *mb = mp->mace;
402     unsigned long flags;
403 
404     spin_lock_irqsave(&mp->lock, flags);
405 
406     __mace_set_address(dev, addr);
407 
408     /* note: setting ADDRCHG clears ENRCV */
409     out_8(&mb->maccc, mp->maccc);
410 
411     spin_unlock_irqrestore(&mp->lock, flags);
412     return 0;
413 }
414 
415 static inline void mace_clean_rings(struct mace_data *mp)
416 {
417     int i;
418 
419     /* free some skb's */
420     for (i = 0; i < N_RX_RING; ++i) {
421 	if (mp->rx_bufs[i] != NULL) {
422 	    dev_kfree_skb(mp->rx_bufs[i]);
423 	    mp->rx_bufs[i] = NULL;
424 	}
425     }
426     for (i = mp->tx_empty; i != mp->tx_fill; ) {
427 	dev_kfree_skb(mp->tx_bufs[i]);
428 	if (++i >= N_TX_RING)
429 	    i = 0;
430     }
431 }
432 
433 static int mace_open(struct net_device *dev)
434 {
435     struct mace_data *mp = netdev_priv(dev);
436     volatile struct mace __iomem *mb = mp->mace;
437     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
438     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
439     volatile struct dbdma_cmd *cp;
440     int i;
441     struct sk_buff *skb;
442     unsigned char *data;
443 
444     /* reset the chip */
445     mace_reset(dev);
446 
447     /* initialize list of sk_buffs for receiving and set up recv dma */
448     mace_clean_rings(mp);
449     memset((char *)mp->rx_cmds, 0, N_RX_RING * sizeof(struct dbdma_cmd));
450     cp = mp->rx_cmds;
451     for (i = 0; i < N_RX_RING - 1; ++i) {
452 	skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
453 	if (!skb) {
454 	    data = dummy_buf;
455 	} else {
456 	    skb_reserve(skb, 2);	/* so IP header lands on 4-byte bdry */
457 	    data = skb->data;
458 	}
459 	mp->rx_bufs[i] = skb;
460 	cp->req_count = cpu_to_le16(RX_BUFLEN);
461 	cp->command = cpu_to_le16(INPUT_LAST + INTR_ALWAYS);
462 	cp->phy_addr = cpu_to_le32(virt_to_bus(data));
463 	cp->xfer_status = 0;
464 	++cp;
465     }
466     mp->rx_bufs[i] = NULL;
467     cp->command = cpu_to_le16(DBDMA_STOP);
468     mp->rx_fill = i;
469     mp->rx_empty = 0;
470 
471     /* Put a branch back to the beginning of the receive command list */
472     ++cp;
473     cp->command = cpu_to_le16(DBDMA_NOP + BR_ALWAYS);
474     cp->cmd_dep = cpu_to_le32(virt_to_bus(mp->rx_cmds));
475 
476     /* start rx dma */
477     out_le32(&rd->control, (RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
478     out_le32(&rd->cmdptr, virt_to_bus(mp->rx_cmds));
479     out_le32(&rd->control, (RUN << 16) | RUN);
480 
481     /* put a branch at the end of the tx command list */
482     cp = mp->tx_cmds + NCMDS_TX * N_TX_RING;
483     cp->command = cpu_to_le16(DBDMA_NOP + BR_ALWAYS);
484     cp->cmd_dep = cpu_to_le32(virt_to_bus(mp->tx_cmds));
485 
486     /* reset tx dma */
487     out_le32(&td->control, (RUN|PAUSE|FLUSH|WAKE) << 16);
488     out_le32(&td->cmdptr, virt_to_bus(mp->tx_cmds));
489     mp->tx_fill = 0;
490     mp->tx_empty = 0;
491     mp->tx_fullup = 0;
492     mp->tx_active = 0;
493     mp->tx_bad_runt = 0;
494 
495     /* turn it on! */
496     out_8(&mb->maccc, mp->maccc);
497     /* enable all interrupts except receive interrupts */
498     out_8(&mb->imr, RCVINT);
499 
500     return 0;
501 }
502 
503 static int mace_close(struct net_device *dev)
504 {
505     struct mace_data *mp = netdev_priv(dev);
506     volatile struct mace __iomem *mb = mp->mace;
507     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
508     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
509 
510     /* disable rx and tx */
511     out_8(&mb->maccc, 0);
512     out_8(&mb->imr, 0xff);		/* disable all intrs */
513 
514     /* disable rx and tx dma */
515     rd->control = cpu_to_le32((RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
516     td->control = cpu_to_le32((RUN|PAUSE|FLUSH|WAKE) << 16); /* clear run bit */
517 
518     mace_clean_rings(mp);
519 
520     return 0;
521 }
522 
523 static inline void mace_set_timeout(struct net_device *dev)
524 {
525     struct mace_data *mp = netdev_priv(dev);
526 
527     if (mp->timeout_active)
528 	del_timer(&mp->tx_timeout);
529     mp->tx_timeout.expires = jiffies + TX_TIMEOUT;
530     add_timer(&mp->tx_timeout);
531     mp->timeout_active = 1;
532 }
533 
534 static netdev_tx_t mace_xmit_start(struct sk_buff *skb, struct net_device *dev)
535 {
536     struct mace_data *mp = netdev_priv(dev);
537     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
538     volatile struct dbdma_cmd *cp, *np;
539     unsigned long flags;
540     int fill, next, len;
541 
542     /* see if there's a free slot in the tx ring */
543     spin_lock_irqsave(&mp->lock, flags);
544     fill = mp->tx_fill;
545     next = fill + 1;
546     if (next >= N_TX_RING)
547 	next = 0;
548     if (next == mp->tx_empty) {
549 	netif_stop_queue(dev);
550 	mp->tx_fullup = 1;
551 	spin_unlock_irqrestore(&mp->lock, flags);
552 	return NETDEV_TX_BUSY;		/* can't take it at the moment */
553     }
554     spin_unlock_irqrestore(&mp->lock, flags);
555 
556     /* partially fill in the dma command block */
557     len = skb->len;
558     if (len > ETH_FRAME_LEN) {
559 	printk(KERN_DEBUG "mace: xmit frame too long (%d)\n", len);
560 	len = ETH_FRAME_LEN;
561     }
562     mp->tx_bufs[fill] = skb;
563     cp = mp->tx_cmds + NCMDS_TX * fill;
564     cp->req_count = cpu_to_le16(len);
565     cp->phy_addr = cpu_to_le32(virt_to_bus(skb->data));
566 
567     np = mp->tx_cmds + NCMDS_TX * next;
568     out_le16(&np->command, DBDMA_STOP);
569 
570     /* poke the tx dma channel */
571     spin_lock_irqsave(&mp->lock, flags);
572     mp->tx_fill = next;
573     if (!mp->tx_bad_runt && mp->tx_active < MAX_TX_ACTIVE) {
574 	out_le16(&cp->xfer_status, 0);
575 	out_le16(&cp->command, OUTPUT_LAST);
576 	out_le32(&td->control, ((RUN|WAKE) << 16) + (RUN|WAKE));
577 	++mp->tx_active;
578 	mace_set_timeout(dev);
579     }
580     if (++next >= N_TX_RING)
581 	next = 0;
582     if (next == mp->tx_empty)
583 	netif_stop_queue(dev);
584     spin_unlock_irqrestore(&mp->lock, flags);
585 
586     return NETDEV_TX_OK;
587 }
588 
589 static void mace_set_multicast(struct net_device *dev)
590 {
591     struct mace_data *mp = netdev_priv(dev);
592     volatile struct mace __iomem *mb = mp->mace;
593     int i;
594     u32 crc;
595     unsigned long flags;
596 
597     spin_lock_irqsave(&mp->lock, flags);
598     mp->maccc &= ~PROM;
599     if (dev->flags & IFF_PROMISC) {
600 	mp->maccc |= PROM;
601     } else {
602 	unsigned char multicast_filter[8];
603 	struct netdev_hw_addr *ha;
604 
605 	if (dev->flags & IFF_ALLMULTI) {
606 	    for (i = 0; i < 8; i++)
607 		multicast_filter[i] = 0xff;
608 	} else {
609 	    for (i = 0; i < 8; i++)
610 		multicast_filter[i] = 0;
611 	    netdev_for_each_mc_addr(ha, dev) {
612 	        crc = ether_crc_le(6, ha->addr);
613 		i = crc >> 26;	/* bit number in multicast_filter */
614 		multicast_filter[i >> 3] |= 1 << (i & 7);
615 	    }
616 	}
617 #if 0
618 	printk("Multicast filter :");
619 	for (i = 0; i < 8; i++)
620 	    printk("%02x ", multicast_filter[i]);
621 	printk("\n");
622 #endif
623 
624 	if (mp->chipid == BROKEN_ADDRCHG_REV)
625 	    out_8(&mb->iac, LOGADDR);
626 	else {
627 	    out_8(&mb->iac, ADDRCHG | LOGADDR);
628 	    while ((in_8(&mb->iac) & ADDRCHG) != 0)
629 		;
630 	}
631 	for (i = 0; i < 8; ++i)
632 	    out_8(&mb->ladrf, multicast_filter[i]);
633 	if (mp->chipid != BROKEN_ADDRCHG_REV)
634 	    out_8(&mb->iac, 0);
635     }
636     /* reset maccc */
637     out_8(&mb->maccc, mp->maccc);
638     spin_unlock_irqrestore(&mp->lock, flags);
639 }
640 
641 static void mace_handle_misc_intrs(struct mace_data *mp, int intr, struct net_device *dev)
642 {
643     volatile struct mace __iomem *mb = mp->mace;
644     static int mace_babbles, mace_jabbers;
645 
646     if (intr & MPCO)
647 	dev->stats.rx_missed_errors += 256;
648     dev->stats.rx_missed_errors += in_8(&mb->mpc);   /* reading clears it */
649     if (intr & RNTPCO)
650 	dev->stats.rx_length_errors += 256;
651     dev->stats.rx_length_errors += in_8(&mb->rntpc); /* reading clears it */
652     if (intr & CERR)
653 	++dev->stats.tx_heartbeat_errors;
654     if (intr & BABBLE)
655 	if (mace_babbles++ < 4)
656 	    printk(KERN_DEBUG "mace: babbling transmitter\n");
657     if (intr & JABBER)
658 	if (mace_jabbers++ < 4)
659 	    printk(KERN_DEBUG "mace: jabbering transceiver\n");
660 }
661 
662 static irqreturn_t mace_interrupt(int irq, void *dev_id)
663 {
664     struct net_device *dev = (struct net_device *) dev_id;
665     struct mace_data *mp = netdev_priv(dev);
666     volatile struct mace __iomem *mb = mp->mace;
667     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
668     volatile struct dbdma_cmd *cp;
669     int intr, fs, i, stat, x;
670     int xcount, dstat;
671     unsigned long flags;
672     /* static int mace_last_fs, mace_last_xcount; */
673 
674     spin_lock_irqsave(&mp->lock, flags);
675     intr = in_8(&mb->ir);		/* read interrupt register */
676     in_8(&mb->xmtrc);			/* get retries */
677     mace_handle_misc_intrs(mp, intr, dev);
678 
679     i = mp->tx_empty;
680     while (in_8(&mb->pr) & XMTSV) {
681 	del_timer(&mp->tx_timeout);
682 	mp->timeout_active = 0;
683 	/*
684 	 * Clear any interrupt indication associated with this status
685 	 * word.  This appears to unlatch any error indication from
686 	 * the DMA controller.
687 	 */
688 	intr = in_8(&mb->ir);
689 	if (intr != 0)
690 	    mace_handle_misc_intrs(mp, intr, dev);
691 	if (mp->tx_bad_runt) {
692 	    fs = in_8(&mb->xmtfs);
693 	    mp->tx_bad_runt = 0;
694 	    out_8(&mb->xmtfc, AUTO_PAD_XMIT);
695 	    continue;
696 	}
697 	dstat = le32_to_cpu(td->status);
698 	/* stop DMA controller */
699 	out_le32(&td->control, RUN << 16);
700 	/*
701 	 * xcount is the number of complete frames which have been
702 	 * written to the fifo but for which status has not been read.
703 	 */
704 	xcount = (in_8(&mb->fifofc) >> XMTFC_SH) & XMTFC_MASK;
705 	if (xcount == 0 || (dstat & DEAD)) {
706 	    /*
707 	     * If a packet was aborted before the DMA controller has
708 	     * finished transferring it, it seems that there are 2 bytes
709 	     * which are stuck in some buffer somewhere.  These will get
710 	     * transmitted as soon as we read the frame status (which
711 	     * reenables the transmit data transfer request).  Turning
712 	     * off the DMA controller and/or resetting the MACE doesn't
713 	     * help.  So we disable auto-padding and FCS transmission
714 	     * so the two bytes will only be a runt packet which should
715 	     * be ignored by other stations.
716 	     */
717 	    out_8(&mb->xmtfc, DXMTFCS);
718 	}
719 	fs = in_8(&mb->xmtfs);
720 	if ((fs & XMTSV) == 0) {
721 	    printk(KERN_ERR "mace: xmtfs not valid! (fs=%x xc=%d ds=%x)\n",
722 		   fs, xcount, dstat);
723 	    mace_reset(dev);
724 		/*
725 		 * XXX mace likes to hang the machine after a xmtfs error.
726 		 * This is hard to reproduce, resetting *may* help
727 		 */
728 	}
729 	cp = mp->tx_cmds + NCMDS_TX * i;
730 	stat = le16_to_cpu(cp->xfer_status);
731 	if ((fs & (UFLO|LCOL|LCAR|RTRY)) || (dstat & DEAD) || xcount == 0) {
732 	    /*
733 	     * Check whether there were in fact 2 bytes written to
734 	     * the transmit FIFO.
735 	     */
736 	    udelay(1);
737 	    x = (in_8(&mb->fifofc) >> XMTFC_SH) & XMTFC_MASK;
738 	    if (x != 0) {
739 		/* there were two bytes with an end-of-packet indication */
740 		mp->tx_bad_runt = 1;
741 		mace_set_timeout(dev);
742 	    } else {
743 		/*
744 		 * Either there weren't the two bytes buffered up, or they
745 		 * didn't have an end-of-packet indication.
746 		 * We flush the transmit FIFO just in case (by setting the
747 		 * XMTFWU bit with the transmitter disabled).
748 		 */
749 		out_8(&mb->maccc, in_8(&mb->maccc) & ~ENXMT);
750 		out_8(&mb->fifocc, in_8(&mb->fifocc) | XMTFWU);
751 		udelay(1);
752 		out_8(&mb->maccc, in_8(&mb->maccc) | ENXMT);
753 		out_8(&mb->xmtfc, AUTO_PAD_XMIT);
754 	    }
755 	}
756 	/* dma should have finished */
757 	if (i == mp->tx_fill) {
758 	    printk(KERN_DEBUG "mace: tx ring ran out? (fs=%x xc=%d ds=%x)\n",
759 		   fs, xcount, dstat);
760 	    continue;
761 	}
762 	/* Update stats */
763 	if (fs & (UFLO|LCOL|LCAR|RTRY)) {
764 	    ++dev->stats.tx_errors;
765 	    if (fs & LCAR)
766 		++dev->stats.tx_carrier_errors;
767 	    if (fs & (UFLO|LCOL|RTRY))
768 		++dev->stats.tx_aborted_errors;
769 	} else {
770 	    dev->stats.tx_bytes += mp->tx_bufs[i]->len;
771 	    ++dev->stats.tx_packets;
772 	}
773 	dev_consume_skb_irq(mp->tx_bufs[i]);
774 	--mp->tx_active;
775 	if (++i >= N_TX_RING)
776 	    i = 0;
777 #if 0
778 	mace_last_fs = fs;
779 	mace_last_xcount = xcount;
780 #endif
781     }
782 
783     if (i != mp->tx_empty) {
784 	mp->tx_fullup = 0;
785 	netif_wake_queue(dev);
786     }
787     mp->tx_empty = i;
788     i += mp->tx_active;
789     if (i >= N_TX_RING)
790 	i -= N_TX_RING;
791     if (!mp->tx_bad_runt && i != mp->tx_fill && mp->tx_active < MAX_TX_ACTIVE) {
792 	do {
793 	    /* set up the next one */
794 	    cp = mp->tx_cmds + NCMDS_TX * i;
795 	    out_le16(&cp->xfer_status, 0);
796 	    out_le16(&cp->command, OUTPUT_LAST);
797 	    ++mp->tx_active;
798 	    if (++i >= N_TX_RING)
799 		i = 0;
800 	} while (i != mp->tx_fill && mp->tx_active < MAX_TX_ACTIVE);
801 	out_le32(&td->control, ((RUN|WAKE) << 16) + (RUN|WAKE));
802 	mace_set_timeout(dev);
803     }
804     spin_unlock_irqrestore(&mp->lock, flags);
805     return IRQ_HANDLED;
806 }
807 
808 static void mace_tx_timeout(struct timer_list *t)
809 {
810     struct mace_data *mp = from_timer(mp, t, tx_timeout);
811     struct net_device *dev = macio_get_drvdata(mp->mdev);
812     volatile struct mace __iomem *mb = mp->mace;
813     volatile struct dbdma_regs __iomem *td = mp->tx_dma;
814     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
815     volatile struct dbdma_cmd *cp;
816     unsigned long flags;
817     int i;
818 
819     spin_lock_irqsave(&mp->lock, flags);
820     mp->timeout_active = 0;
821     if (mp->tx_active == 0 && !mp->tx_bad_runt)
822 	goto out;
823 
824     /* update various counters */
825     mace_handle_misc_intrs(mp, in_8(&mb->ir), dev);
826 
827     cp = mp->tx_cmds + NCMDS_TX * mp->tx_empty;
828 
829     /* turn off both tx and rx and reset the chip */
830     out_8(&mb->maccc, 0);
831     printk(KERN_ERR "mace: transmit timeout - resetting\n");
832     dbdma_reset(td);
833     mace_reset(dev);
834 
835     /* restart rx dma */
836     cp = bus_to_virt(le32_to_cpu(rd->cmdptr));
837     dbdma_reset(rd);
838     out_le16(&cp->xfer_status, 0);
839     out_le32(&rd->cmdptr, virt_to_bus(cp));
840     out_le32(&rd->control, (RUN << 16) | RUN);
841 
842     /* fix up the transmit side */
843     i = mp->tx_empty;
844     mp->tx_active = 0;
845     ++dev->stats.tx_errors;
846     if (mp->tx_bad_runt) {
847 	mp->tx_bad_runt = 0;
848     } else if (i != mp->tx_fill) {
849 	dev_kfree_skb_irq(mp->tx_bufs[i]);
850 	if (++i >= N_TX_RING)
851 	    i = 0;
852 	mp->tx_empty = i;
853     }
854     mp->tx_fullup = 0;
855     netif_wake_queue(dev);
856     if (i != mp->tx_fill) {
857 	cp = mp->tx_cmds + NCMDS_TX * i;
858 	out_le16(&cp->xfer_status, 0);
859 	out_le16(&cp->command, OUTPUT_LAST);
860 	out_le32(&td->cmdptr, virt_to_bus(cp));
861 	out_le32(&td->control, (RUN << 16) | RUN);
862 	++mp->tx_active;
863 	mace_set_timeout(dev);
864     }
865 
866     /* turn it back on */
867     out_8(&mb->imr, RCVINT);
868     out_8(&mb->maccc, mp->maccc);
869 
870 out:
871     spin_unlock_irqrestore(&mp->lock, flags);
872 }
873 
874 static irqreturn_t mace_txdma_intr(int irq, void *dev_id)
875 {
876 	return IRQ_HANDLED;
877 }
878 
879 static irqreturn_t mace_rxdma_intr(int irq, void *dev_id)
880 {
881     struct net_device *dev = (struct net_device *) dev_id;
882     struct mace_data *mp = netdev_priv(dev);
883     volatile struct dbdma_regs __iomem *rd = mp->rx_dma;
884     volatile struct dbdma_cmd *cp, *np;
885     int i, nb, stat, next;
886     struct sk_buff *skb;
887     unsigned frame_status;
888     static int mace_lost_status;
889     unsigned char *data;
890     unsigned long flags;
891 
892     spin_lock_irqsave(&mp->lock, flags);
893     for (i = mp->rx_empty; i != mp->rx_fill; ) {
894 	cp = mp->rx_cmds + i;
895 	stat = le16_to_cpu(cp->xfer_status);
896 	if ((stat & ACTIVE) == 0) {
897 	    next = i + 1;
898 	    if (next >= N_RX_RING)
899 		next = 0;
900 	    np = mp->rx_cmds + next;
901 	    if (next != mp->rx_fill &&
902 		(le16_to_cpu(np->xfer_status) & ACTIVE) != 0) {
903 		printk(KERN_DEBUG "mace: lost a status word\n");
904 		++mace_lost_status;
905 	    } else
906 		break;
907 	}
908 	nb = le16_to_cpu(cp->req_count) - le16_to_cpu(cp->res_count);
909 	out_le16(&cp->command, DBDMA_STOP);
910 	/* got a packet, have a look at it */
911 	skb = mp->rx_bufs[i];
912 	if (!skb) {
913 	    ++dev->stats.rx_dropped;
914 	} else if (nb > 8) {
915 	    data = skb->data;
916 	    frame_status = (data[nb-3] << 8) + data[nb-4];
917 	    if (frame_status & (RS_OFLO|RS_CLSN|RS_FRAMERR|RS_FCSERR)) {
918 		++dev->stats.rx_errors;
919 		if (frame_status & RS_OFLO)
920 		    ++dev->stats.rx_over_errors;
921 		if (frame_status & RS_FRAMERR)
922 		    ++dev->stats.rx_frame_errors;
923 		if (frame_status & RS_FCSERR)
924 		    ++dev->stats.rx_crc_errors;
925 	    } else {
926 		/* Mace feature AUTO_STRIP_RCV is on by default, dropping the
927 		 * FCS on frames with 802.3 headers. This means that Ethernet
928 		 * frames have 8 extra octets at the end, while 802.3 frames
929 		 * have only 4. We need to correctly account for this. */
930 		if (*(unsigned short *)(data+12) < 1536) /* 802.3 header */
931 		    nb -= 4;
932 		else	/* Ethernet header; mace includes FCS */
933 		    nb -= 8;
934 		skb_put(skb, nb);
935 		skb->protocol = eth_type_trans(skb, dev);
936 		dev->stats.rx_bytes += skb->len;
937 		netif_rx(skb);
938 		mp->rx_bufs[i] = NULL;
939 		++dev->stats.rx_packets;
940 	    }
941 	} else {
942 	    ++dev->stats.rx_errors;
943 	    ++dev->stats.rx_length_errors;
944 	}
945 
946 	/* advance to next */
947 	if (++i >= N_RX_RING)
948 	    i = 0;
949     }
950     mp->rx_empty = i;
951 
952     i = mp->rx_fill;
953     for (;;) {
954 	next = i + 1;
955 	if (next >= N_RX_RING)
956 	    next = 0;
957 	if (next == mp->rx_empty)
958 	    break;
959 	cp = mp->rx_cmds + i;
960 	skb = mp->rx_bufs[i];
961 	if (!skb) {
962 	    skb = netdev_alloc_skb(dev, RX_BUFLEN + 2);
963 	    if (skb) {
964 		skb_reserve(skb, 2);
965 		mp->rx_bufs[i] = skb;
966 	    }
967 	}
968 	cp->req_count = cpu_to_le16(RX_BUFLEN);
969 	data = skb? skb->data: dummy_buf;
970 	cp->phy_addr = cpu_to_le32(virt_to_bus(data));
971 	out_le16(&cp->xfer_status, 0);
972 	out_le16(&cp->command, INPUT_LAST + INTR_ALWAYS);
973 #if 0
974 	if ((le32_to_cpu(rd->status) & ACTIVE) != 0) {
975 	    out_le32(&rd->control, (PAUSE << 16) | PAUSE);
976 	    while ((in_le32(&rd->status) & ACTIVE) != 0)
977 		;
978 	}
979 #endif
980 	i = next;
981     }
982     if (i != mp->rx_fill) {
983 	out_le32(&rd->control, ((RUN|WAKE) << 16) | (RUN|WAKE));
984 	mp->rx_fill = i;
985     }
986     spin_unlock_irqrestore(&mp->lock, flags);
987     return IRQ_HANDLED;
988 }
989 
990 static const struct of_device_id mace_match[] =
991 {
992 	{
993 	.name 		= "mace",
994 	},
995 	{},
996 };
997 MODULE_DEVICE_TABLE (of, mace_match);
998 
999 static struct macio_driver mace_driver =
1000 {
1001 	.driver = {
1002 		.name 		= "mace",
1003 		.owner		= THIS_MODULE,
1004 		.of_match_table	= mace_match,
1005 	},
1006 	.probe		= mace_probe,
1007 	.remove		= mace_remove,
1008 };
1009 
1010 
1011 static int __init mace_init(void)
1012 {
1013 	return macio_register_driver(&mace_driver);
1014 }
1015 
1016 static void __exit mace_cleanup(void)
1017 {
1018 	macio_unregister_driver(&mace_driver);
1019 
1020 	kfree(dummy_buf);
1021 	dummy_buf = NULL;
1022 }
1023 
1024 MODULE_AUTHOR("Paul Mackerras");
1025 MODULE_DESCRIPTION("PowerMac MACE driver.");
1026 module_param(port_aaui, int, 0);
1027 MODULE_PARM_DESC(port_aaui, "MACE uses AAUI port (0-1)");
1028 MODULE_LICENSE("GPL");
1029 
1030 module_init(mace_init);
1031 module_exit(mace_cleanup);
1032