xref: /openbmc/linux/drivers/net/ethernet/ibm/emac/mal.c (revision e3b9f1e8)
1 /*
2  * drivers/net/ethernet/ibm/emac/mal.c
3  *
4  * Memory Access Layer (MAL) support
5  *
6  * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
7  *                <benh@kernel.crashing.org>
8  *
9  * Based on the arch/ppc version of the driver:
10  *
11  * Copyright (c) 2004, 2005 Zultys Technologies.
12  * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
13  *
14  * Based on original work by
15  *      Benjamin Herrenschmidt <benh@kernel.crashing.org>,
16  *      David Gibson <hermes@gibson.dropbear.id.au>,
17  *
18  *      Armin Kuster <akuster@mvista.com>
19  *      Copyright 2002 MontaVista Softare Inc.
20  *
21  * This program is free software; you can redistribute  it and/or modify it
22  * under  the terms of  the GNU General  Public License as published by the
23  * Free Software Foundation;  either version 2 of the  License, or (at your
24  * option) any later version.
25  *
26  */
27 
28 #include <linux/delay.h>
29 #include <linux/slab.h>
30 #include <linux/of_irq.h>
31 
32 #include "core.h"
33 #include <asm/dcr-regs.h>
34 
35 static int mal_count;
36 
37 int mal_register_commac(struct mal_instance *mal, struct mal_commac *commac)
38 {
39 	unsigned long flags;
40 
41 	spin_lock_irqsave(&mal->lock, flags);
42 
43 	MAL_DBG(mal, "reg(%08x, %08x)" NL,
44 		commac->tx_chan_mask, commac->rx_chan_mask);
45 
46 	/* Don't let multiple commacs claim the same channel(s) */
47 	if ((mal->tx_chan_mask & commac->tx_chan_mask) ||
48 	    (mal->rx_chan_mask & commac->rx_chan_mask)) {
49 		spin_unlock_irqrestore(&mal->lock, flags);
50 		printk(KERN_WARNING "mal%d: COMMAC channels conflict!\n",
51 		       mal->index);
52 		return -EBUSY;
53 	}
54 
55 	if (list_empty(&mal->list))
56 		napi_enable(&mal->napi);
57 	mal->tx_chan_mask |= commac->tx_chan_mask;
58 	mal->rx_chan_mask |= commac->rx_chan_mask;
59 	list_add(&commac->list, &mal->list);
60 
61 	spin_unlock_irqrestore(&mal->lock, flags);
62 
63 	return 0;
64 }
65 
66 void mal_unregister_commac(struct mal_instance	*mal,
67 		struct mal_commac *commac)
68 {
69 	unsigned long flags;
70 
71 	spin_lock_irqsave(&mal->lock, flags);
72 
73 	MAL_DBG(mal, "unreg(%08x, %08x)" NL,
74 		commac->tx_chan_mask, commac->rx_chan_mask);
75 
76 	mal->tx_chan_mask &= ~commac->tx_chan_mask;
77 	mal->rx_chan_mask &= ~commac->rx_chan_mask;
78 	list_del_init(&commac->list);
79 	if (list_empty(&mal->list))
80 		napi_disable(&mal->napi);
81 
82 	spin_unlock_irqrestore(&mal->lock, flags);
83 }
84 
85 int mal_set_rcbs(struct mal_instance *mal, int channel, unsigned long size)
86 {
87 	BUG_ON(channel < 0 || channel >= mal->num_rx_chans ||
88 	       size > MAL_MAX_RX_SIZE);
89 
90 	MAL_DBG(mal, "set_rbcs(%d, %lu)" NL, channel, size);
91 
92 	if (size & 0xf) {
93 		printk(KERN_WARNING
94 		       "mal%d: incorrect RX size %lu for the channel %d\n",
95 		       mal->index, size, channel);
96 		return -EINVAL;
97 	}
98 
99 	set_mal_dcrn(mal, MAL_RCBS(channel), size >> 4);
100 	return 0;
101 }
102 
103 int mal_tx_bd_offset(struct mal_instance *mal, int channel)
104 {
105 	BUG_ON(channel < 0 || channel >= mal->num_tx_chans);
106 
107 	return channel * NUM_TX_BUFF;
108 }
109 
110 int mal_rx_bd_offset(struct mal_instance *mal, int channel)
111 {
112 	BUG_ON(channel < 0 || channel >= mal->num_rx_chans);
113 	return mal->num_tx_chans * NUM_TX_BUFF + channel * NUM_RX_BUFF;
114 }
115 
116 void mal_enable_tx_channel(struct mal_instance *mal, int channel)
117 {
118 	unsigned long flags;
119 
120 	spin_lock_irqsave(&mal->lock, flags);
121 
122 	MAL_DBG(mal, "enable_tx(%d)" NL, channel);
123 
124 	set_mal_dcrn(mal, MAL_TXCASR,
125 		     get_mal_dcrn(mal, MAL_TXCASR) | MAL_CHAN_MASK(channel));
126 
127 	spin_unlock_irqrestore(&mal->lock, flags);
128 }
129 
130 void mal_disable_tx_channel(struct mal_instance *mal, int channel)
131 {
132 	set_mal_dcrn(mal, MAL_TXCARR, MAL_CHAN_MASK(channel));
133 
134 	MAL_DBG(mal, "disable_tx(%d)" NL, channel);
135 }
136 
137 void mal_enable_rx_channel(struct mal_instance *mal, int channel)
138 {
139 	unsigned long flags;
140 
141 	/*
142 	 * On some 4xx PPC's (e.g. 460EX/GT), the rx channel is a multiple
143 	 * of 8, but enabling in MAL_RXCASR needs the divided by 8 value
144 	 * for the bitmask
145 	 */
146 	if (!(channel % 8))
147 		channel >>= 3;
148 
149 	spin_lock_irqsave(&mal->lock, flags);
150 
151 	MAL_DBG(mal, "enable_rx(%d)" NL, channel);
152 
153 	set_mal_dcrn(mal, MAL_RXCASR,
154 		     get_mal_dcrn(mal, MAL_RXCASR) | MAL_CHAN_MASK(channel));
155 
156 	spin_unlock_irqrestore(&mal->lock, flags);
157 }
158 
159 void mal_disable_rx_channel(struct mal_instance *mal, int channel)
160 {
161 	/*
162 	 * On some 4xx PPC's (e.g. 460EX/GT), the rx channel is a multiple
163 	 * of 8, but enabling in MAL_RXCASR needs the divided by 8 value
164 	 * for the bitmask
165 	 */
166 	if (!(channel % 8))
167 		channel >>= 3;
168 
169 	set_mal_dcrn(mal, MAL_RXCARR, MAL_CHAN_MASK(channel));
170 
171 	MAL_DBG(mal, "disable_rx(%d)" NL, channel);
172 }
173 
174 void mal_poll_add(struct mal_instance *mal, struct mal_commac *commac)
175 {
176 	unsigned long flags;
177 
178 	spin_lock_irqsave(&mal->lock, flags);
179 
180 	MAL_DBG(mal, "poll_add(%p)" NL, commac);
181 
182 	/* starts disabled */
183 	set_bit(MAL_COMMAC_POLL_DISABLED, &commac->flags);
184 
185 	list_add_tail(&commac->poll_list, &mal->poll_list);
186 
187 	spin_unlock_irqrestore(&mal->lock, flags);
188 }
189 
190 void mal_poll_del(struct mal_instance *mal, struct mal_commac *commac)
191 {
192 	unsigned long flags;
193 
194 	spin_lock_irqsave(&mal->lock, flags);
195 
196 	MAL_DBG(mal, "poll_del(%p)" NL, commac);
197 
198 	list_del(&commac->poll_list);
199 
200 	spin_unlock_irqrestore(&mal->lock, flags);
201 }
202 
203 /* synchronized by mal_poll() */
204 static inline void mal_enable_eob_irq(struct mal_instance *mal)
205 {
206 	MAL_DBG2(mal, "enable_irq" NL);
207 
208 	// XXX might want to cache MAL_CFG as the DCR read can be slooooow
209 	set_mal_dcrn(mal, MAL_CFG, get_mal_dcrn(mal, MAL_CFG) | MAL_CFG_EOPIE);
210 }
211 
212 /* synchronized by NAPI state */
213 static inline void mal_disable_eob_irq(struct mal_instance *mal)
214 {
215 	// XXX might want to cache MAL_CFG as the DCR read can be slooooow
216 	set_mal_dcrn(mal, MAL_CFG, get_mal_dcrn(mal, MAL_CFG) & ~MAL_CFG_EOPIE);
217 
218 	MAL_DBG2(mal, "disable_irq" NL);
219 }
220 
221 static irqreturn_t mal_serr(int irq, void *dev_instance)
222 {
223 	struct mal_instance *mal = dev_instance;
224 
225 	u32 esr = get_mal_dcrn(mal, MAL_ESR);
226 
227 	/* Clear the error status register */
228 	set_mal_dcrn(mal, MAL_ESR, esr);
229 
230 	MAL_DBG(mal, "SERR %08x" NL, esr);
231 
232 	if (esr & MAL_ESR_EVB) {
233 		if (esr & MAL_ESR_DE) {
234 			/* We ignore Descriptor error,
235 			 * TXDE or RXDE interrupt will be generated anyway.
236 			 */
237 			return IRQ_HANDLED;
238 		}
239 
240 		if (esr & MAL_ESR_PEIN) {
241 			/* PLB error, it's probably buggy hardware or
242 			 * incorrect physical address in BD (i.e. bug)
243 			 */
244 			if (net_ratelimit())
245 				printk(KERN_ERR
246 				       "mal%d: system error, "
247 				       "PLB (ESR = 0x%08x)\n",
248 				       mal->index, esr);
249 			return IRQ_HANDLED;
250 		}
251 
252 		/* OPB error, it's probably buggy hardware or incorrect
253 		 * EBC setup
254 		 */
255 		if (net_ratelimit())
256 			printk(KERN_ERR
257 			       "mal%d: system error, OPB (ESR = 0x%08x)\n",
258 			       mal->index, esr);
259 	}
260 	return IRQ_HANDLED;
261 }
262 
263 static inline void mal_schedule_poll(struct mal_instance *mal)
264 {
265 	if (likely(napi_schedule_prep(&mal->napi))) {
266 		MAL_DBG2(mal, "schedule_poll" NL);
267 		spin_lock(&mal->lock);
268 		mal_disable_eob_irq(mal);
269 		spin_unlock(&mal->lock);
270 		__napi_schedule(&mal->napi);
271 	} else
272 		MAL_DBG2(mal, "already in poll" NL);
273 }
274 
275 static irqreturn_t mal_txeob(int irq, void *dev_instance)
276 {
277 	struct mal_instance *mal = dev_instance;
278 
279 	u32 r = get_mal_dcrn(mal, MAL_TXEOBISR);
280 
281 	MAL_DBG2(mal, "txeob %08x" NL, r);
282 
283 	mal_schedule_poll(mal);
284 	set_mal_dcrn(mal, MAL_TXEOBISR, r);
285 
286 #ifdef CONFIG_PPC_DCR_NATIVE
287 	if (mal_has_feature(mal, MAL_FTR_CLEAR_ICINTSTAT))
288 		mtdcri(SDR0, DCRN_SDR_ICINTSTAT,
289 				(mfdcri(SDR0, DCRN_SDR_ICINTSTAT) | ICINTSTAT_ICTX));
290 #endif
291 
292 	return IRQ_HANDLED;
293 }
294 
295 static irqreturn_t mal_rxeob(int irq, void *dev_instance)
296 {
297 	struct mal_instance *mal = dev_instance;
298 
299 	u32 r = get_mal_dcrn(mal, MAL_RXEOBISR);
300 
301 	MAL_DBG2(mal, "rxeob %08x" NL, r);
302 
303 	mal_schedule_poll(mal);
304 	set_mal_dcrn(mal, MAL_RXEOBISR, r);
305 
306 #ifdef CONFIG_PPC_DCR_NATIVE
307 	if (mal_has_feature(mal, MAL_FTR_CLEAR_ICINTSTAT))
308 		mtdcri(SDR0, DCRN_SDR_ICINTSTAT,
309 				(mfdcri(SDR0, DCRN_SDR_ICINTSTAT) | ICINTSTAT_ICRX));
310 #endif
311 
312 	return IRQ_HANDLED;
313 }
314 
315 static irqreturn_t mal_txde(int irq, void *dev_instance)
316 {
317 	struct mal_instance *mal = dev_instance;
318 
319 	u32 deir = get_mal_dcrn(mal, MAL_TXDEIR);
320 	set_mal_dcrn(mal, MAL_TXDEIR, deir);
321 
322 	MAL_DBG(mal, "txde %08x" NL, deir);
323 
324 	if (net_ratelimit())
325 		printk(KERN_ERR
326 		       "mal%d: TX descriptor error (TXDEIR = 0x%08x)\n",
327 		       mal->index, deir);
328 
329 	return IRQ_HANDLED;
330 }
331 
332 static irqreturn_t mal_rxde(int irq, void *dev_instance)
333 {
334 	struct mal_instance *mal = dev_instance;
335 	struct list_head *l;
336 
337 	u32 deir = get_mal_dcrn(mal, MAL_RXDEIR);
338 
339 	MAL_DBG(mal, "rxde %08x" NL, deir);
340 
341 	list_for_each(l, &mal->list) {
342 		struct mal_commac *mc = list_entry(l, struct mal_commac, list);
343 		if (deir & mc->rx_chan_mask) {
344 			set_bit(MAL_COMMAC_RX_STOPPED, &mc->flags);
345 			mc->ops->rxde(mc->dev);
346 		}
347 	}
348 
349 	mal_schedule_poll(mal);
350 	set_mal_dcrn(mal, MAL_RXDEIR, deir);
351 
352 	return IRQ_HANDLED;
353 }
354 
355 static irqreturn_t mal_int(int irq, void *dev_instance)
356 {
357 	struct mal_instance *mal = dev_instance;
358 	u32 esr = get_mal_dcrn(mal, MAL_ESR);
359 
360 	if (esr & MAL_ESR_EVB) {
361 		/* descriptor error */
362 		if (esr & MAL_ESR_DE) {
363 			if (esr & MAL_ESR_CIDT)
364 				return mal_rxde(irq, dev_instance);
365 			else
366 				return mal_txde(irq, dev_instance);
367 		} else { /* SERR */
368 			return mal_serr(irq, dev_instance);
369 		}
370 	}
371 	return IRQ_HANDLED;
372 }
373 
374 void mal_poll_disable(struct mal_instance *mal, struct mal_commac *commac)
375 {
376 	/* Spinlock-type semantics: only one caller disable poll at a time */
377 	while (test_and_set_bit(MAL_COMMAC_POLL_DISABLED, &commac->flags))
378 		msleep(1);
379 
380 	/* Synchronize with the MAL NAPI poller */
381 	napi_synchronize(&mal->napi);
382 }
383 
384 void mal_poll_enable(struct mal_instance *mal, struct mal_commac *commac)
385 {
386 	smp_wmb();
387 	clear_bit(MAL_COMMAC_POLL_DISABLED, &commac->flags);
388 
389 	/* Feels better to trigger a poll here to catch up with events that
390 	 * may have happened on this channel while disabled. It will most
391 	 * probably be delayed until the next interrupt but that's mostly a
392 	 * non-issue in the context where this is called.
393 	 */
394 	napi_schedule(&mal->napi);
395 }
396 
397 static int mal_poll(struct napi_struct *napi, int budget)
398 {
399 	struct mal_instance *mal = container_of(napi, struct mal_instance, napi);
400 	struct list_head *l;
401 	int received = 0;
402 	unsigned long flags;
403 
404 	MAL_DBG2(mal, "poll(%d)" NL, budget);
405 
406 	/* Process TX skbs */
407 	list_for_each(l, &mal->poll_list) {
408 		struct mal_commac *mc =
409 			list_entry(l, struct mal_commac, poll_list);
410 		mc->ops->poll_tx(mc->dev);
411 	}
412 
413 	/* Process RX skbs.
414 	 *
415 	 * We _might_ need something more smart here to enforce polling
416 	 * fairness.
417 	 */
418 	list_for_each(l, &mal->poll_list) {
419 		struct mal_commac *mc =
420 			list_entry(l, struct mal_commac, poll_list);
421 		int n;
422 		if (unlikely(test_bit(MAL_COMMAC_POLL_DISABLED, &mc->flags)))
423 			continue;
424 		n = mc->ops->poll_rx(mc->dev, budget - received);
425 		if (n) {
426 			received += n;
427 			if (received >= budget)
428 				return budget;
429 		}
430 	}
431 
432 	if (napi_complete_done(napi, received)) {
433 		/* We need to disable IRQs to protect from RXDE IRQ here */
434 		spin_lock_irqsave(&mal->lock, flags);
435 		mal_enable_eob_irq(mal);
436 		spin_unlock_irqrestore(&mal->lock, flags);
437 	}
438 
439 	/* Check for "rotting" packet(s) */
440 	list_for_each(l, &mal->poll_list) {
441 		struct mal_commac *mc =
442 			list_entry(l, struct mal_commac, poll_list);
443 		if (unlikely(test_bit(MAL_COMMAC_POLL_DISABLED, &mc->flags)))
444 			continue;
445 		if (unlikely(mc->ops->peek_rx(mc->dev) ||
446 			     test_bit(MAL_COMMAC_RX_STOPPED, &mc->flags))) {
447 			MAL_DBG2(mal, "rotting packet" NL);
448 			if (!napi_reschedule(napi))
449 				goto more_work;
450 
451 			spin_lock_irqsave(&mal->lock, flags);
452 			mal_disable_eob_irq(mal);
453 			spin_unlock_irqrestore(&mal->lock, flags);
454 		}
455 		mc->ops->poll_tx(mc->dev);
456 	}
457 
458  more_work:
459 	MAL_DBG2(mal, "poll() %d <- %d" NL, budget, received);
460 	return received;
461 }
462 
463 static void mal_reset(struct mal_instance *mal)
464 {
465 	int n = 10;
466 
467 	MAL_DBG(mal, "reset" NL);
468 
469 	set_mal_dcrn(mal, MAL_CFG, MAL_CFG_SR);
470 
471 	/* Wait for reset to complete (1 system clock) */
472 	while ((get_mal_dcrn(mal, MAL_CFG) & MAL_CFG_SR) && n)
473 		--n;
474 
475 	if (unlikely(!n))
476 		printk(KERN_ERR "mal%d: reset timeout\n", mal->index);
477 }
478 
479 int mal_get_regs_len(struct mal_instance *mal)
480 {
481 	return sizeof(struct emac_ethtool_regs_subhdr) +
482 	    sizeof(struct mal_regs);
483 }
484 
485 void *mal_dump_regs(struct mal_instance *mal, void *buf)
486 {
487 	struct emac_ethtool_regs_subhdr *hdr = buf;
488 	struct mal_regs *regs = (struct mal_regs *)(hdr + 1);
489 	int i;
490 
491 	hdr->version = mal->version;
492 	hdr->index = mal->index;
493 
494 	regs->tx_count = mal->num_tx_chans;
495 	regs->rx_count = mal->num_rx_chans;
496 
497 	regs->cfg = get_mal_dcrn(mal, MAL_CFG);
498 	regs->esr = get_mal_dcrn(mal, MAL_ESR);
499 	regs->ier = get_mal_dcrn(mal, MAL_IER);
500 	regs->tx_casr = get_mal_dcrn(mal, MAL_TXCASR);
501 	regs->tx_carr = get_mal_dcrn(mal, MAL_TXCARR);
502 	regs->tx_eobisr = get_mal_dcrn(mal, MAL_TXEOBISR);
503 	regs->tx_deir = get_mal_dcrn(mal, MAL_TXDEIR);
504 	regs->rx_casr = get_mal_dcrn(mal, MAL_RXCASR);
505 	regs->rx_carr = get_mal_dcrn(mal, MAL_RXCARR);
506 	regs->rx_eobisr = get_mal_dcrn(mal, MAL_RXEOBISR);
507 	regs->rx_deir = get_mal_dcrn(mal, MAL_RXDEIR);
508 
509 	for (i = 0; i < regs->tx_count; ++i)
510 		regs->tx_ctpr[i] = get_mal_dcrn(mal, MAL_TXCTPR(i));
511 
512 	for (i = 0; i < regs->rx_count; ++i) {
513 		regs->rx_ctpr[i] = get_mal_dcrn(mal, MAL_RXCTPR(i));
514 		regs->rcbs[i] = get_mal_dcrn(mal, MAL_RCBS(i));
515 	}
516 	return regs + 1;
517 }
518 
519 static int mal_probe(struct platform_device *ofdev)
520 {
521 	struct mal_instance *mal;
522 	int err = 0, i, bd_size;
523 	int index = mal_count++;
524 	unsigned int dcr_base;
525 	const u32 *prop;
526 	u32 cfg;
527 	unsigned long irqflags;
528 	irq_handler_t hdlr_serr, hdlr_txde, hdlr_rxde;
529 
530 	mal = kzalloc(sizeof(struct mal_instance), GFP_KERNEL);
531 	if (!mal)
532 		return -ENOMEM;
533 
534 	mal->index = index;
535 	mal->ofdev = ofdev;
536 	mal->version = of_device_is_compatible(ofdev->dev.of_node, "ibm,mcmal2") ? 2 : 1;
537 
538 	MAL_DBG(mal, "probe" NL);
539 
540 	prop = of_get_property(ofdev->dev.of_node, "num-tx-chans", NULL);
541 	if (prop == NULL) {
542 		printk(KERN_ERR
543 		       "mal%d: can't find MAL num-tx-chans property!\n",
544 		       index);
545 		err = -ENODEV;
546 		goto fail;
547 	}
548 	mal->num_tx_chans = prop[0];
549 
550 	prop = of_get_property(ofdev->dev.of_node, "num-rx-chans", NULL);
551 	if (prop == NULL) {
552 		printk(KERN_ERR
553 		       "mal%d: can't find MAL num-rx-chans property!\n",
554 		       index);
555 		err = -ENODEV;
556 		goto fail;
557 	}
558 	mal->num_rx_chans = prop[0];
559 
560 	dcr_base = dcr_resource_start(ofdev->dev.of_node, 0);
561 	if (dcr_base == 0) {
562 		printk(KERN_ERR
563 		       "mal%d: can't find DCR resource!\n", index);
564 		err = -ENODEV;
565 		goto fail;
566 	}
567 	mal->dcr_host = dcr_map(ofdev->dev.of_node, dcr_base, 0x100);
568 	if (!DCR_MAP_OK(mal->dcr_host)) {
569 		printk(KERN_ERR
570 		       "mal%d: failed to map DCRs !\n", index);
571 		err = -ENODEV;
572 		goto fail;
573 	}
574 
575 	if (of_device_is_compatible(ofdev->dev.of_node, "ibm,mcmal-405ez")) {
576 #if defined(CONFIG_IBM_EMAC_MAL_CLR_ICINTSTAT) && \
577 		defined(CONFIG_IBM_EMAC_MAL_COMMON_ERR)
578 		mal->features |= (MAL_FTR_CLEAR_ICINTSTAT |
579 				MAL_FTR_COMMON_ERR_INT);
580 #else
581 		printk(KERN_ERR "%pOF: Support for 405EZ not enabled!\n",
582 				ofdev->dev.of_node);
583 		err = -ENODEV;
584 		goto fail;
585 #endif
586 	}
587 
588 	mal->txeob_irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
589 	mal->rxeob_irq = irq_of_parse_and_map(ofdev->dev.of_node, 1);
590 	mal->serr_irq = irq_of_parse_and_map(ofdev->dev.of_node, 2);
591 
592 	if (mal_has_feature(mal, MAL_FTR_COMMON_ERR_INT)) {
593 		mal->txde_irq = mal->rxde_irq = mal->serr_irq;
594 	} else {
595 		mal->txde_irq = irq_of_parse_and_map(ofdev->dev.of_node, 3);
596 		mal->rxde_irq = irq_of_parse_and_map(ofdev->dev.of_node, 4);
597 	}
598 
599 	if (!mal->txeob_irq || !mal->rxeob_irq || !mal->serr_irq ||
600 	    !mal->txde_irq  || !mal->rxde_irq) {
601 		printk(KERN_ERR
602 		       "mal%d: failed to map interrupts !\n", index);
603 		err = -ENODEV;
604 		goto fail_unmap;
605 	}
606 
607 	INIT_LIST_HEAD(&mal->poll_list);
608 	INIT_LIST_HEAD(&mal->list);
609 	spin_lock_init(&mal->lock);
610 
611 	init_dummy_netdev(&mal->dummy_dev);
612 
613 	netif_napi_add(&mal->dummy_dev, &mal->napi, mal_poll,
614 		       CONFIG_IBM_EMAC_POLL_WEIGHT);
615 
616 	/* Load power-on reset defaults */
617 	mal_reset(mal);
618 
619 	/* Set the MAL configuration register */
620 	cfg = (mal->version == 2) ? MAL2_CFG_DEFAULT : MAL1_CFG_DEFAULT;
621 	cfg |= MAL_CFG_PLBB | MAL_CFG_OPBBL | MAL_CFG_LEA;
622 
623 	/* Current Axon is not happy with priority being non-0, it can
624 	 * deadlock, fix it up here
625 	 */
626 	if (of_device_is_compatible(ofdev->dev.of_node, "ibm,mcmal-axon"))
627 		cfg &= ~(MAL2_CFG_RPP_10 | MAL2_CFG_WPP_10);
628 
629 	/* Apply configuration */
630 	set_mal_dcrn(mal, MAL_CFG, cfg);
631 
632 	/* Allocate space for BD rings */
633 	BUG_ON(mal->num_tx_chans <= 0 || mal->num_tx_chans > 32);
634 	BUG_ON(mal->num_rx_chans <= 0 || mal->num_rx_chans > 32);
635 
636 	bd_size = sizeof(struct mal_descriptor) *
637 		(NUM_TX_BUFF * mal->num_tx_chans +
638 		 NUM_RX_BUFF * mal->num_rx_chans);
639 	mal->bd_virt = dma_zalloc_coherent(&ofdev->dev, bd_size, &mal->bd_dma,
640 					   GFP_KERNEL);
641 	if (mal->bd_virt == NULL) {
642 		err = -ENOMEM;
643 		goto fail_unmap;
644 	}
645 
646 	for (i = 0; i < mal->num_tx_chans; ++i)
647 		set_mal_dcrn(mal, MAL_TXCTPR(i), mal->bd_dma +
648 			     sizeof(struct mal_descriptor) *
649 			     mal_tx_bd_offset(mal, i));
650 
651 	for (i = 0; i < mal->num_rx_chans; ++i)
652 		set_mal_dcrn(mal, MAL_RXCTPR(i), mal->bd_dma +
653 			     sizeof(struct mal_descriptor) *
654 			     mal_rx_bd_offset(mal, i));
655 
656 	if (mal_has_feature(mal, MAL_FTR_COMMON_ERR_INT)) {
657 		irqflags = IRQF_SHARED;
658 		hdlr_serr = hdlr_txde = hdlr_rxde = mal_int;
659 	} else {
660 		irqflags = 0;
661 		hdlr_serr = mal_serr;
662 		hdlr_txde = mal_txde;
663 		hdlr_rxde = mal_rxde;
664 	}
665 
666 	err = request_irq(mal->serr_irq, hdlr_serr, irqflags, "MAL SERR", mal);
667 	if (err)
668 		goto fail2;
669 	err = request_irq(mal->txde_irq, hdlr_txde, irqflags, "MAL TX DE", mal);
670 	if (err)
671 		goto fail3;
672 	err = request_irq(mal->txeob_irq, mal_txeob, 0, "MAL TX EOB", mal);
673 	if (err)
674 		goto fail4;
675 	err = request_irq(mal->rxde_irq, hdlr_rxde, irqflags, "MAL RX DE", mal);
676 	if (err)
677 		goto fail5;
678 	err = request_irq(mal->rxeob_irq, mal_rxeob, 0, "MAL RX EOB", mal);
679 	if (err)
680 		goto fail6;
681 
682 	/* Enable all MAL SERR interrupt sources */
683 	set_mal_dcrn(mal, MAL_IER, MAL_IER_EVENTS);
684 
685 	/* Enable EOB interrupt */
686 	mal_enable_eob_irq(mal);
687 
688 	printk(KERN_INFO
689 	       "MAL v%d %pOF, %d TX channels, %d RX channels\n",
690 	       mal->version, ofdev->dev.of_node,
691 	       mal->num_tx_chans, mal->num_rx_chans);
692 
693 	/* Advertise this instance to the rest of the world */
694 	wmb();
695 	platform_set_drvdata(ofdev, mal);
696 
697 	return 0;
698 
699  fail6:
700 	free_irq(mal->rxde_irq, mal);
701  fail5:
702 	free_irq(mal->txeob_irq, mal);
703  fail4:
704 	free_irq(mal->txde_irq, mal);
705  fail3:
706 	free_irq(mal->serr_irq, mal);
707  fail2:
708 	dma_free_coherent(&ofdev->dev, bd_size, mal->bd_virt, mal->bd_dma);
709  fail_unmap:
710 	dcr_unmap(mal->dcr_host, 0x100);
711  fail:
712 	kfree(mal);
713 
714 	return err;
715 }
716 
717 static int mal_remove(struct platform_device *ofdev)
718 {
719 	struct mal_instance *mal = platform_get_drvdata(ofdev);
720 
721 	MAL_DBG(mal, "remove" NL);
722 
723 	/* Synchronize with scheduled polling */
724 	napi_disable(&mal->napi);
725 
726 	if (!list_empty(&mal->list))
727 		/* This is *very* bad */
728 		WARN(1, KERN_EMERG
729 		       "mal%d: commac list is not empty on remove!\n",
730 		       mal->index);
731 
732 	free_irq(mal->serr_irq, mal);
733 	free_irq(mal->txde_irq, mal);
734 	free_irq(mal->txeob_irq, mal);
735 	free_irq(mal->rxde_irq, mal);
736 	free_irq(mal->rxeob_irq, mal);
737 
738 	mal_reset(mal);
739 
740 	dma_free_coherent(&ofdev->dev,
741 			  sizeof(struct mal_descriptor) *
742 			  (NUM_TX_BUFF * mal->num_tx_chans +
743 			   NUM_RX_BUFF * mal->num_rx_chans), mal->bd_virt,
744 			  mal->bd_dma);
745 	kfree(mal);
746 
747 	return 0;
748 }
749 
750 static const struct of_device_id mal_platform_match[] =
751 {
752 	{
753 		.compatible	= "ibm,mcmal",
754 	},
755 	{
756 		.compatible	= "ibm,mcmal2",
757 	},
758 	/* Backward compat */
759 	{
760 		.type		= "mcmal-dma",
761 		.compatible	= "ibm,mcmal",
762 	},
763 	{
764 		.type		= "mcmal-dma",
765 		.compatible	= "ibm,mcmal2",
766 	},
767 	{},
768 };
769 
770 static struct platform_driver mal_of_driver = {
771 	.driver = {
772 		.name = "mcmal",
773 		.of_match_table = mal_platform_match,
774 	},
775 	.probe = mal_probe,
776 	.remove = mal_remove,
777 };
778 
779 int __init mal_init(void)
780 {
781 	return platform_driver_register(&mal_of_driver);
782 }
783 
784 void mal_exit(void)
785 {
786 	platform_driver_unregister(&mal_of_driver);
787 }
788