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/prom.h>
24#include <asm/dbdma.h>
25#include <asm/io.h>
26#include <asm/macio.h>
27
28#include "mace.h"
29
30static 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
45struct 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
80static int mace_open(struct net_device *dev);
81static int mace_close(struct net_device *dev);
82static netdev_tx_t mace_xmit_start(struct sk_buff *skb, struct net_device *dev);
83static void mace_set_multicast(struct net_device *dev);
84static void mace_reset(struct net_device *dev);
85static int mace_set_address(struct net_device *dev, void *addr);
86static irqreturn_t mace_interrupt(int irq, void *dev_id);
87static irqreturn_t mace_txdma_intr(int irq, void *dev_id);
88static irqreturn_t mace_rxdma_intr(int irq, void *dev_id);
89static void mace_set_timeout(struct net_device *dev);
90static void mace_tx_timeout(struct timer_list *t);
91static inline void dbdma_reset(volatile struct dbdma_regs __iomem *dma);
92static inline void mace_clean_rings(struct mace_data *mp);
93static 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 */
98static unsigned char *dummy_buf;
99
100static 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
109static 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
274static 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
302static 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
317static 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
372static 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
393static 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
410static 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
428static 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
498static 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
518static 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
529static 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
584static 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
636static 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
657static 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
803static 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_irq(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
865out:
866    spin_unlock_irqrestore(&mp->lock, flags);
867}
868
869static irqreturn_t mace_txdma_intr(int irq, void *dev_id)
870{
871	return IRQ_HANDLED;
872}
873
874static 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
985static const struct of_device_id mace_match[] =
986{
987	{
988	.name 		= "mace",
989	},
990	{},
991};
992MODULE_DEVICE_TABLE (of, mace_match);
993
994static 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
1006static int __init mace_init(void)
1007{
1008	return macio_register_driver(&mace_driver);
1009}
1010
1011static void __exit mace_cleanup(void)
1012{
1013	macio_unregister_driver(&mace_driver);
1014
1015	kfree(dummy_buf);
1016	dummy_buf = NULL;
1017}
1018
1019MODULE_AUTHOR("Paul Mackerras");
1020MODULE_DESCRIPTION("PowerMac MACE driver.");
1021module_param(port_aaui, int, 0);
1022MODULE_PARM_DESC(port_aaui, "MACE uses AAUI port (0-1)");
1023MODULE_LICENSE("GPL");
1024
1025module_init(mace_init);
1026module_exit(mace_cleanup);
1027