1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2013 Daisuke Aoyama <aoyama@peach.ne.jp>
5 * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@bluezbox.com>
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/bus.h>
36#include <sys/kernel.h>
37#include <sys/lock.h>
38#include <sys/malloc.h>
39#include <sys/module.h>
40#include <sys/mutex.h>
41#include <sys/queue.h>
42#include <sys/resource.h>
43#include <sys/rman.h>
44
45#include <dev/ofw/openfirm.h>
46#include <dev/ofw/ofw_bus.h>
47#include <dev/ofw/ofw_bus_subr.h>
48
49#include <vm/vm.h>
50#include <vm/pmap.h>
51#include <machine/bus.h>
52
53#include "bcm2835_dma.h"
54#include "bcm2835_vcbus.h"
55
56#define	MAX_REG			9
57
58/* private flags */
59#define	BCM_DMA_CH_USED		0x00000001
60#define	BCM_DMA_CH_FREE		0x40000000
61#define	BCM_DMA_CH_UNMAP	0x80000000
62
63/* Register Map (4.2.1.2) */
64#define	BCM_DMA_CS(n)		(0x100*(n) + 0x00)
65#define		CS_ACTIVE		(1 <<  0)
66#define		CS_END			(1 <<  1)
67#define		CS_INT			(1 <<  2)
68#define		CS_DREQ			(1 <<  3)
69#define		CS_ISPAUSED		(1 <<  4)
70#define		CS_ISHELD		(1 <<  5)
71#define		CS_ISWAIT		(1 <<  6)
72#define		CS_ERR			(1 <<  8)
73#define		CS_WAITWRT		(1 << 28)
74#define		CS_DISDBG		(1 << 29)
75#define		CS_ABORT		(1 << 30)
76#define		CS_RESET		(1U << 31)
77#define	BCM_DMA_CBADDR(n)	(0x100*(n) + 0x04)
78#define	BCM_DMA_INFO(n)		(0x100*(n) + 0x08)
79#define		INFO_INT_EN		(1 << 0)
80#define		INFO_TDMODE		(1 << 1)
81#define		INFO_WAIT_RESP		(1 << 3)
82#define		INFO_D_INC		(1 << 4)
83#define		INFO_D_WIDTH		(1 << 5)
84#define		INFO_D_DREQ		(1 << 6)
85#define		INFO_S_INC		(1 << 8)
86#define		INFO_S_WIDTH		(1 << 9)
87#define		INFO_S_DREQ		(1 << 10)
88#define		INFO_WAITS_SHIFT	(21)
89#define		INFO_PERMAP_SHIFT	(16)
90#define		INFO_PERMAP_MASK	(0x1f << INFO_PERMAP_SHIFT)
91
92#define	BCM_DMA_SRC(n)		(0x100*(n) + 0x0C)
93#define	BCM_DMA_DST(n)		(0x100*(n) + 0x10)
94#define	BCM_DMA_LEN(n)		(0x100*(n) + 0x14)
95#define	BCM_DMA_STRIDE(n)	(0x100*(n) + 0x18)
96#define	BCM_DMA_CBNEXT(n)	(0x100*(n) + 0x1C)
97#define	BCM_DMA_DEBUG(n)	(0x100*(n) + 0x20)
98#define		DEBUG_ERROR_MASK	(7)
99
100#define	BCM_DMA_INT_STATUS	0xfe0
101#define	BCM_DMA_ENABLE		0xff0
102
103/* relative offset from BCM_VC_DMA0_BASE (p.39) */
104#define	BCM_DMA_CH(n)		(0x100*(n))
105
106/* channels used by GPU */
107#define	BCM_DMA_CH_BULK		0
108#define	BCM_DMA_CH_FAST1	2
109#define	BCM_DMA_CH_FAST2	3
110
111#define	BCM_DMA_CH_GPU_MASK	((1 << BCM_DMA_CH_BULK) |	\
112				 (1 << BCM_DMA_CH_FAST1) |	\
113				 (1 << BCM_DMA_CH_FAST2))
114
115/* DMA Control Block - 256bit aligned (p.40) */
116struct bcm_dma_cb {
117	uint32_t info;		/* Transfer Information */
118	uint32_t src;		/* Source Address */
119	uint32_t dst;		/* Destination Address */
120	uint32_t len;		/* Transfer Length */
121	uint32_t stride;	/* 2D Mode Stride */
122	uint32_t next;		/* Next Control Block Address */
123	uint32_t rsvd1;		/* Reserved */
124	uint32_t rsvd2;		/* Reserved */
125};
126
127#ifdef DEBUG
128static void bcm_dma_cb_dump(struct bcm_dma_cb *cb);
129static void bcm_dma_reg_dump(int ch);
130#endif
131
132/* DMA channel private info */
133struct bcm_dma_ch {
134	int			ch;
135	uint32_t		flags;
136	struct bcm_dma_cb *	cb;
137	uint32_t		vc_cb;
138	bus_dmamap_t		dma_map;
139	void 			(*intr_func)(int, void *);
140	void *			intr_arg;
141};
142
143struct bcm_dma_softc {
144	device_t		sc_dev;
145	struct mtx		sc_mtx;
146	struct resource *	sc_mem;
147	struct resource *	sc_irq[BCM_DMA_CH_MAX];
148	void *			sc_intrhand[BCM_DMA_CH_MAX];
149	struct bcm_dma_ch	sc_dma_ch[BCM_DMA_CH_MAX];
150	bus_dma_tag_t		sc_dma_tag;
151};
152
153static struct bcm_dma_softc *bcm_dma_sc = NULL;
154static uint32_t bcm_dma_channel_mask;
155
156static struct ofw_compat_data compat_data[] = {
157	{"broadcom,bcm2835-dma",	1},
158	{"brcm,bcm2835-dma",		1},
159	{NULL,				0}
160};
161
162static void
163bcm_dmamap_cb(void *arg, bus_dma_segment_t *segs,
164	int nseg, int err)
165{
166        bus_addr_t *addr;
167
168        if (err)
169                return;
170
171        addr = (bus_addr_t*)arg;
172        *addr = ARMC_TO_VCBUS(segs[0].ds_addr);
173}
174
175static void
176bcm_dma_reset(device_t dev, int ch)
177{
178	struct bcm_dma_softc *sc = device_get_softc(dev);
179	struct bcm_dma_cb *cb;
180	uint32_t cs;
181	int count;
182
183	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
184		return;
185
186	cs = bus_read_4(sc->sc_mem, BCM_DMA_CS(ch));
187
188	if (cs & CS_ACTIVE) {
189		/* pause current task */
190		bus_write_4(sc->sc_mem, BCM_DMA_CS(ch), 0);
191
192		count = 1000;
193		do {
194			cs = bus_read_4(sc->sc_mem, BCM_DMA_CS(ch));
195		} while (!(cs & CS_ISPAUSED) && (count-- > 0));
196
197		if (!(cs & CS_ISPAUSED)) {
198			device_printf(dev,
199			    "Can't abort DMA transfer at channel %d\n", ch);
200		}
201
202		bus_write_4(sc->sc_mem, BCM_DMA_CBNEXT(ch), 0);
203
204		/* Complete everything, clear interrupt */
205		bus_write_4(sc->sc_mem, BCM_DMA_CS(ch),
206		    CS_ABORT | CS_INT | CS_END| CS_ACTIVE);
207	}
208
209	/* clear control blocks */
210	bus_write_4(sc->sc_mem, BCM_DMA_CBADDR(ch), 0);
211	bus_write_4(sc->sc_mem, BCM_DMA_CBNEXT(ch), 0);
212
213	/* Reset control block */
214	cb = sc->sc_dma_ch[ch].cb;
215	bzero(cb, sizeof(*cb));
216	cb->info = INFO_WAIT_RESP;
217}
218
219static int
220bcm_dma_init(device_t dev)
221{
222	struct bcm_dma_softc *sc = device_get_softc(dev);
223	uint32_t reg;
224	struct bcm_dma_ch *ch;
225	void *cb_virt;
226	vm_paddr_t cb_phys;
227	int err;
228	int i;
229
230	/*
231	 * Only channels set in bcm_dma_channel_mask can be controlled by us.
232	 * The others are out of our control as well as the corresponding bits
233	 * in both BCM_DMA_ENABLE and BCM_DMA_INT_STATUS global registers. As
234	 * these registers are RW ones, there is no safe way how to write only
235	 * the bits which can be controlled by us.
236	 *
237	 * Fortunately, after reset, all channels are enabled in BCM_DMA_ENABLE
238	 * register and all statuses are cleared in BCM_DMA_INT_STATUS one.
239	 * Not touching these registers is a trade off between correct
240	 * initialization which does not count on anything and not messing up
241	 * something we have no control over.
242	 */
243	reg = bus_read_4(sc->sc_mem, BCM_DMA_ENABLE);
244	if ((reg & bcm_dma_channel_mask) != bcm_dma_channel_mask)
245		device_printf(dev, "channels are not enabled\n");
246	reg = bus_read_4(sc->sc_mem, BCM_DMA_INT_STATUS);
247	if ((reg & bcm_dma_channel_mask) != 0)
248		device_printf(dev, "statuses are not cleared\n");
249
250	/*
251	 * Allocate DMA chunks control blocks based on p.40 of the peripheral
252	 * spec - control block should be 32-bit aligned.  The DMA controller
253	 * has a full 32-bit register dedicated to this address, so we do not
254	 * need to bother with the per-SoC peripheral restrictions.
255	 */
256	err = bus_dma_tag_create(bus_get_dma_tag(dev),
257	    1, 0, BUS_SPACE_MAXADDR_32BIT,
258	    BUS_SPACE_MAXADDR, NULL, NULL,
259	    sizeof(struct bcm_dma_cb), 1,
260	    sizeof(struct bcm_dma_cb),
261	    BUS_DMA_ALLOCNOW, NULL, NULL,
262	    &sc->sc_dma_tag);
263
264	if (err) {
265		device_printf(dev, "failed allocate DMA tag\n");
266		return (err);
267	}
268
269	/* setup initial settings */
270	for (i = 0; i < BCM_DMA_CH_MAX; i++) {
271		ch = &sc->sc_dma_ch[i];
272
273		bzero(ch, sizeof(struct bcm_dma_ch));
274		ch->ch = i;
275		ch->flags = BCM_DMA_CH_UNMAP;
276
277		if ((bcm_dma_channel_mask & (1 << i)) == 0)
278			continue;
279
280		err = bus_dmamem_alloc(sc->sc_dma_tag, &cb_virt,
281		    BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
282		    &ch->dma_map);
283		if (err) {
284			device_printf(dev, "cannot allocate DMA memory\n");
285			break;
286		}
287
288		/*
289		 * Least alignment for busdma-allocated stuff is cache
290		 * line size, so just make sure nothing stupid happened
291		 * and we got properly aligned address
292		 */
293		if ((uintptr_t)cb_virt & 0x1f) {
294			device_printf(dev,
295			    "DMA address is not 32-bytes aligned: %p\n",
296			    (void*)cb_virt);
297			break;
298		}
299
300		err = bus_dmamap_load(sc->sc_dma_tag, ch->dma_map, cb_virt,
301		    sizeof(struct bcm_dma_cb), bcm_dmamap_cb, &cb_phys,
302		    BUS_DMA_WAITOK);
303		if (err) {
304			device_printf(dev, "cannot load DMA memory\n");
305			break;
306		}
307
308		ch->cb = cb_virt;
309		ch->vc_cb = cb_phys;
310		ch->flags = BCM_DMA_CH_FREE;
311		ch->cb->info = INFO_WAIT_RESP;
312
313		/* reset DMA engine */
314		bus_write_4(sc->sc_mem, BCM_DMA_CS(i), CS_RESET);
315	}
316
317	return (0);
318}
319
320/*
321 * Allocate DMA channel for further use, returns channel # or
322 *     BCM_DMA_CH_INVALID
323 */
324int
325bcm_dma_allocate(int req_ch)
326{
327	struct bcm_dma_softc *sc = bcm_dma_sc;
328	int ch = BCM_DMA_CH_INVALID;
329	int i;
330
331	if (req_ch >= BCM_DMA_CH_MAX)
332		return (BCM_DMA_CH_INVALID);
333
334	/* Auto(req_ch < 0) or CH specified */
335	mtx_lock(&sc->sc_mtx);
336
337	if (req_ch < 0) {
338		for (i = 0; i < BCM_DMA_CH_MAX; i++) {
339			if (sc->sc_dma_ch[i].flags & BCM_DMA_CH_FREE) {
340				ch = i;
341				sc->sc_dma_ch[ch].flags &= ~BCM_DMA_CH_FREE;
342				sc->sc_dma_ch[ch].flags |= BCM_DMA_CH_USED;
343				break;
344			}
345		}
346	}
347	else {
348		if (sc->sc_dma_ch[req_ch].flags & BCM_DMA_CH_FREE) {
349			ch = req_ch;
350			sc->sc_dma_ch[ch].flags &= ~BCM_DMA_CH_FREE;
351			sc->sc_dma_ch[ch].flags |= BCM_DMA_CH_USED;
352		}
353	}
354
355	mtx_unlock(&sc->sc_mtx);
356	return (ch);
357}
358
359/*
360 * Frees allocated channel. Returns 0 on success, -1 otherwise
361 */
362int
363bcm_dma_free(int ch)
364{
365	struct bcm_dma_softc *sc = bcm_dma_sc;
366
367	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
368		return (-1);
369
370	mtx_lock(&sc->sc_mtx);
371	if (sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED) {
372		sc->sc_dma_ch[ch].flags |= BCM_DMA_CH_FREE;
373		sc->sc_dma_ch[ch].flags &= ~BCM_DMA_CH_USED;
374		sc->sc_dma_ch[ch].intr_func = NULL;
375		sc->sc_dma_ch[ch].intr_arg = NULL;
376
377		/* reset DMA engine */
378		bcm_dma_reset(sc->sc_dev, ch);
379	}
380
381	mtx_unlock(&sc->sc_mtx);
382	return (0);
383}
384
385/*
386 * Assign handler function for channel interrupt
387 * Returns 0 on success, -1 otherwise
388 */
389int
390bcm_dma_setup_intr(int ch, void (*func)(int, void *), void *arg)
391{
392	struct bcm_dma_softc *sc = bcm_dma_sc;
393	struct bcm_dma_cb *cb;
394
395	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
396		return (-1);
397
398	if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
399		return (-1);
400
401	sc->sc_dma_ch[ch].intr_func = func;
402	sc->sc_dma_ch[ch].intr_arg = arg;
403	cb = sc->sc_dma_ch[ch].cb;
404	cb->info |= INFO_INT_EN;
405
406	return (0);
407}
408
409/*
410 * Setup DMA source parameters
411 *     ch - channel number
412 *     dreq - hardware DREQ # or BCM_DMA_DREQ_NONE if
413 *         source is physical memory
414 *     inc_addr - BCM_DMA_INC_ADDR if source address
415 *         should be increased after each access or
416 *         BCM_DMA_SAME_ADDR if address should remain
417 *         the same
418 *     width - size of read operation, BCM_DMA_32BIT
419 *         for 32bit bursts, BCM_DMA_128BIT for 128 bits
420 *
421 * Returns 0 on success, -1 otherwise
422 */
423int
424bcm_dma_setup_src(int ch, int dreq, int inc_addr, int width)
425{
426	struct bcm_dma_softc *sc = bcm_dma_sc;
427	uint32_t info;
428
429	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
430		return (-1);
431
432	if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
433		return (-1);
434
435	info = sc->sc_dma_ch[ch].cb->info;
436	info &= ~INFO_PERMAP_MASK;
437	info |= (dreq << INFO_PERMAP_SHIFT) & INFO_PERMAP_MASK;
438
439	if (dreq)
440		info |= INFO_S_DREQ;
441	else
442		info &= ~INFO_S_DREQ;
443
444	if (width == BCM_DMA_128BIT)
445		info |= INFO_S_WIDTH;
446	else
447		info &= ~INFO_S_WIDTH;
448
449	if (inc_addr == BCM_DMA_INC_ADDR)
450		info |= INFO_S_INC;
451	else
452		info &= ~INFO_S_INC;
453
454	sc->sc_dma_ch[ch].cb->info = info;
455
456	return (0);
457}
458
459/*
460 * Setup DMA destination parameters
461 *     ch - channel number
462 *     dreq - hardware DREQ # or BCM_DMA_DREQ_NONE if
463 *         destination is physical memory
464 *     inc_addr - BCM_DMA_INC_ADDR if source address
465 *         should be increased after each access or
466 *         BCM_DMA_SAME_ADDR if address should remain
467 *         the same
468 *     width - size of write operation, BCM_DMA_32BIT
469 *         for 32bit bursts, BCM_DMA_128BIT for 128 bits
470 *
471 * Returns 0 on success, -1 otherwise
472 */
473int
474bcm_dma_setup_dst(int ch, int dreq, int inc_addr, int width)
475{
476	struct bcm_dma_softc *sc = bcm_dma_sc;
477	uint32_t info;
478
479	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
480		return (-1);
481
482	if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
483		return (-1);
484
485	info = sc->sc_dma_ch[ch].cb->info;
486	info &= ~INFO_PERMAP_MASK;
487	info |= (dreq << INFO_PERMAP_SHIFT) & INFO_PERMAP_MASK;
488
489	if (dreq)
490		info |= INFO_D_DREQ;
491	else
492		info &= ~INFO_D_DREQ;
493
494	if (width == BCM_DMA_128BIT)
495		info |= INFO_D_WIDTH;
496	else
497		info &= ~INFO_D_WIDTH;
498
499	if (inc_addr == BCM_DMA_INC_ADDR)
500		info |= INFO_D_INC;
501	else
502		info &= ~INFO_D_INC;
503
504	sc->sc_dma_ch[ch].cb->info = info;
505
506	return (0);
507}
508
509#ifdef DEBUG
510void
511bcm_dma_cb_dump(struct bcm_dma_cb *cb)
512{
513
514	printf("DMA CB ");
515	printf("INFO: %8.8x ", cb->info);
516	printf("SRC: %8.8x ", cb->src);
517	printf("DST: %8.8x ", cb->dst);
518	printf("LEN: %8.8x ", cb->len);
519	printf("\n");
520	printf("STRIDE: %8.8x ", cb->stride);
521	printf("NEXT: %8.8x ", cb->next);
522	printf("RSVD1: %8.8x ", cb->rsvd1);
523	printf("RSVD2: %8.8x ", cb->rsvd2);
524	printf("\n");
525}
526
527void
528bcm_dma_reg_dump(int ch)
529{
530	struct bcm_dma_softc *sc = bcm_dma_sc;
531	int i;
532	uint32_t reg;
533
534	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
535		return;
536
537	printf("DMA%d: ", ch);
538	for (i = 0; i < MAX_REG; i++) {
539		reg = bus_read_4(sc->sc_mem, BCM_DMA_CH(ch) + i*4);
540		printf("%8.8x ", reg);
541	}
542	printf("\n");
543}
544#endif
545
546/*
547 * Start DMA transaction
548 *     ch - channel number
549 *     src, dst - source and destination address in
550 *         ARM physical memory address space.
551 *     len - amount of bytes to be transferred
552 *
553 * Returns 0 on success, -1 otherwise
554 */
555int
556bcm_dma_start(int ch, vm_paddr_t src, vm_paddr_t dst, int len)
557{
558	struct bcm_dma_softc *sc = bcm_dma_sc;
559	struct bcm_dma_cb *cb;
560
561	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
562		return (-1);
563
564	if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
565		return (-1);
566
567	cb = sc->sc_dma_ch[ch].cb;
568	cb->src = ARMC_TO_VCBUS(src);
569	cb->dst = ARMC_TO_VCBUS(dst);
570
571	cb->len = len;
572
573	bus_dmamap_sync(sc->sc_dma_tag,
574	    sc->sc_dma_ch[ch].dma_map, BUS_DMASYNC_PREWRITE);
575
576	bus_write_4(sc->sc_mem, BCM_DMA_CBADDR(ch),
577	    sc->sc_dma_ch[ch].vc_cb);
578	bus_write_4(sc->sc_mem, BCM_DMA_CS(ch), CS_ACTIVE);
579
580#ifdef DEBUG
581	bcm_dma_cb_dump(sc->sc_dma_ch[ch].cb);
582	bcm_dma_reg_dump(ch);
583#endif
584
585	return (0);
586}
587
588/*
589 * Get length requested for DMA transaction
590 *     ch - channel number
591 *
592 * Returns size of transaction, 0 if channel is invalid
593 */
594uint32_t
595bcm_dma_length(int ch)
596{
597	struct bcm_dma_softc *sc = bcm_dma_sc;
598	struct bcm_dma_cb *cb;
599
600	if (ch < 0 || ch >= BCM_DMA_CH_MAX)
601		return (0);
602
603	if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
604		return (0);
605
606	cb = sc->sc_dma_ch[ch].cb;
607
608	return (cb->len);
609}
610
611static void
612bcm_dma_intr(void *arg)
613{
614	struct bcm_dma_softc *sc = bcm_dma_sc;
615	struct bcm_dma_ch *ch = (struct bcm_dma_ch *)arg;
616	uint32_t cs, debug;
617
618	/* my interrupt? */
619	cs = bus_read_4(sc->sc_mem, BCM_DMA_CS(ch->ch));
620
621	/*
622	 * Is it an active channel?  Our diagnostics could be better here, but
623	 * it's not necessarily an easy task to resolve a rid/resource to an
624	 * actual irq number.  We'd want to do this to set a flag indicating
625	 * whether the irq is shared or not, so we know to complain.
626	 */
627	if (!(ch->flags & BCM_DMA_CH_USED))
628		return;
629
630	/* Again, we can't complain here.  The same logic applies. */
631	if (!(cs & (CS_INT | CS_ERR)))
632		return;
633
634	if (cs & CS_ERR) {
635		debug = bus_read_4(sc->sc_mem, BCM_DMA_DEBUG(ch->ch));
636		device_printf(sc->sc_dev, "DMA error %d on CH%d\n",
637			debug & DEBUG_ERROR_MASK, ch->ch);
638		bus_write_4(sc->sc_mem, BCM_DMA_DEBUG(ch->ch),
639		    debug & DEBUG_ERROR_MASK);
640		bcm_dma_reset(sc->sc_dev, ch->ch);
641	}
642
643	if (cs & CS_INT) {
644		/* acknowledge interrupt */
645		bus_write_4(sc->sc_mem, BCM_DMA_CS(ch->ch),
646		    CS_INT | CS_END);
647
648		/* Prepare for possible access to len field */
649		bus_dmamap_sync(sc->sc_dma_tag, ch->dma_map,
650		    BUS_DMASYNC_POSTWRITE);
651
652		/* save callback function and argument */
653		if (ch->intr_func)
654			ch->intr_func(ch->ch, ch->intr_arg);
655	}
656}
657
658static int
659bcm_dma_probe(device_t dev)
660{
661
662	if (!ofw_bus_status_okay(dev))
663		return (ENXIO);
664
665	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
666		return (ENXIO);
667
668	device_set_desc(dev, "BCM2835 DMA Controller");
669	return (BUS_PROBE_DEFAULT);
670}
671
672static int
673bcm_dma_attach(device_t dev)
674{
675	struct bcm_dma_softc *sc = device_get_softc(dev);
676	phandle_t node;
677	int rid, err = 0;
678	int i;
679
680	sc->sc_dev = dev;
681
682	if (bcm_dma_sc)
683		return (ENXIO);
684
685	for (i = 0; i < BCM_DMA_CH_MAX; i++) {
686		sc->sc_irq[i] = NULL;
687		sc->sc_intrhand[i] = NULL;
688	}
689
690	/* Get DMA channel mask. */
691	node = ofw_bus_get_node(sc->sc_dev);
692	if (OF_getencprop(node, "brcm,dma-channel-mask", &bcm_dma_channel_mask,
693	    sizeof(bcm_dma_channel_mask)) == -1 &&
694	    OF_getencprop(node, "broadcom,channels", &bcm_dma_channel_mask,
695	    sizeof(bcm_dma_channel_mask)) == -1) {
696		device_printf(dev, "could not get channel mask property\n");
697		return (ENXIO);
698	}
699
700	/* Mask out channels used by GPU. */
701	bcm_dma_channel_mask &= ~BCM_DMA_CH_GPU_MASK;
702
703	/* DMA0 - DMA14 */
704	rid = 0;
705	sc->sc_mem = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
706	if (sc->sc_mem == NULL) {
707		device_printf(dev, "could not allocate memory resource\n");
708		return (ENXIO);
709	}
710
711	/* IRQ DMA0 - DMA11 XXX NOT USE DMA12(spurious?) */
712	for (rid = 0; rid < BCM_DMA_CH_MAX; rid++) {
713		if ((bcm_dma_channel_mask & (1 << rid)) == 0)
714			continue;
715
716		sc->sc_irq[rid] = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
717		    RF_ACTIVE | RF_SHAREABLE);
718		if (sc->sc_irq[rid] == NULL) {
719			device_printf(dev, "cannot allocate interrupt\n");
720			err = ENXIO;
721			goto fail;
722		}
723		if (bus_setup_intr(dev, sc->sc_irq[rid], INTR_TYPE_MISC | INTR_MPSAFE,
724				   NULL, bcm_dma_intr, &sc->sc_dma_ch[rid],
725				   &sc->sc_intrhand[rid])) {
726			device_printf(dev, "cannot setup interrupt handler\n");
727			err = ENXIO;
728			goto fail;
729		}
730	}
731
732	mtx_init(&sc->sc_mtx, "bcmdma", "bcmdma", MTX_DEF);
733	bcm_dma_sc = sc;
734
735	err = bcm_dma_init(dev);
736	if (err)
737		goto fail;
738
739	return (err);
740
741fail:
742	if (sc->sc_mem)
743		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem);
744
745	for (i = 0; i < BCM_DMA_CH_MAX; i++) {
746		if (sc->sc_intrhand[i])
747			bus_teardown_intr(dev, sc->sc_irq[i], sc->sc_intrhand[i]);
748		if (sc->sc_irq[i])
749			bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq[i]);
750	}
751
752	return (err);
753}
754
755static device_method_t bcm_dma_methods[] = {
756	DEVMETHOD(device_probe,		bcm_dma_probe),
757	DEVMETHOD(device_attach,	bcm_dma_attach),
758	{ 0, 0 }
759};
760
761static driver_t bcm_dma_driver = {
762	"bcm_dma",
763	bcm_dma_methods,
764	sizeof(struct bcm_dma_softc),
765};
766
767static devclass_t bcm_dma_devclass;
768
769DRIVER_MODULE(bcm_dma, simplebus, bcm_dma_driver, bcm_dma_devclass, 0, 0);
770MODULE_VERSION(bcm_dma, 1);
771