xref: /freebsd/sys/arm/broadcom/bcm2835/bcm2835_sdhci.c (revision 6e660824a82f590542932de52f128db584029893)
1 /*-
2  * Copyright (c) 2012 Oleksandr Tymoshenko <gonzo@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bio.h>
33 #include <sys/bus.h>
34 #include <sys/conf.h>
35 #include <sys/endian.h>
36 #include <sys/kernel.h>
37 #include <sys/kthread.h>
38 #include <sys/lock.h>
39 #include <sys/malloc.h>
40 #include <sys/module.h>
41 #include <sys/mutex.h>
42 #include <sys/queue.h>
43 #include <sys/resource.h>
44 #include <sys/rman.h>
45 #include <sys/taskqueue.h>
46 #include <sys/time.h>
47 #include <sys/timetc.h>
48 #include <sys/watchdog.h>
49 
50 #include <sys/kdb.h>
51 
52 #include <machine/bus.h>
53 #include <machine/cpu.h>
54 #include <machine/cpufunc.h>
55 #include <machine/resource.h>
56 #include <machine/frame.h>
57 #include <machine/intr.h>
58 
59 #include <dev/fdt/fdt_common.h>
60 #include <dev/ofw/ofw_bus.h>
61 #include <dev/ofw/ofw_bus_subr.h>
62 
63 #include <dev/mmc/bridge.h>
64 #include <dev/mmc/mmcreg.h>
65 #include <dev/mmc/mmcbrvar.h>
66 
67 #include <dev/sdhci/sdhci.h>
68 #include "sdhci_if.h"
69 
70 #include "bcm2835_dma.h"
71 #include "bcm2835_vcbus.h"
72 
73 #define	BCM2835_DEFAULT_SDHCI_FREQ	50
74 
75 #define	BCM_SDHCI_BUFFER_SIZE		512
76 
77 #ifdef DEBUG
78 #define dprintf(fmt, args...) do { printf("%s(): ", __func__);   \
79     printf(fmt,##args); } while (0)
80 #else
81 #define dprintf(fmt, args...)
82 #endif
83 
84 /*
85  * Arasan HC seems to have problem with Data CRC on lower frequencies.
86  * Use this tunable to cap initialization sequence frequency at higher
87  * value. Default is standard 400kHz
88  */
89 static int bcm2835_sdhci_min_freq = 400000;
90 static int bcm2835_sdhci_hs = 1;
91 static int bcm2835_sdhci_pio_mode = 0;
92 
93 TUNABLE_INT("hw.bcm2835.sdhci.min_freq", &bcm2835_sdhci_min_freq);
94 TUNABLE_INT("hw.bcm2835.sdhci.hs", &bcm2835_sdhci_hs);
95 TUNABLE_INT("hw.bcm2835.sdhci.pio_mode", &bcm2835_sdhci_pio_mode);
96 
97 struct bcm_sdhci_dmamap_arg {
98 	bus_addr_t		sc_dma_busaddr;
99 };
100 
101 struct bcm_sdhci_softc {
102 	device_t		sc_dev;
103 	struct mtx		sc_mtx;
104 	struct resource *	sc_mem_res;
105 	struct resource *	sc_irq_res;
106 	bus_space_tag_t		sc_bst;
107 	bus_space_handle_t	sc_bsh;
108 	void *			sc_intrhand;
109 	struct mmc_request *	sc_req;
110 	struct mmc_data *	sc_data;
111 	uint32_t		sc_flags;
112 #define	LPC_SD_FLAGS_IGNORECRC		(1 << 0)
113 	int			sc_xfer_direction;
114 #define	DIRECTION_READ		0
115 #define	DIRECTION_WRITE		1
116 	int			sc_xfer_done;
117 	int			sc_bus_busy;
118 	struct sdhci_slot	sc_slot;
119 	int			sc_dma_inuse;
120 	int			sc_dma_ch;
121 	bus_dma_tag_t		sc_dma_tag;
122 	bus_dmamap_t		sc_dma_map;
123 	vm_paddr_t		sc_sdhci_buffer_phys;
124 };
125 
126 static int bcm_sdhci_probe(device_t);
127 static int bcm_sdhci_attach(device_t);
128 static int bcm_sdhci_detach(device_t);
129 static void bcm_sdhci_intr(void *);
130 
131 static int bcm_sdhci_get_ro(device_t, device_t);
132 static void bcm_sdhci_dma_intr(int ch, void *arg);
133 
134 #define	bcm_sdhci_lock(_sc)						\
135     mtx_lock(&_sc->sc_mtx);
136 #define	bcm_sdhci_unlock(_sc)						\
137     mtx_unlock(&_sc->sc_mtx);
138 
139 static void
140 bcm_dmamap_cb(void *arg, bus_dma_segment_t *segs,
141 	int nseg, int err)
142 {
143         bus_addr_t *addr;
144 
145         if (err)
146                 return;
147 
148         addr = (bus_addr_t*)arg;
149         *addr = segs[0].ds_addr;
150 }
151 
152 static int
153 bcm_sdhci_probe(device_t dev)
154 {
155 	if (!ofw_bus_is_compatible(dev, "broadcom,bcm2835-sdhci"))
156 		return (ENXIO);
157 
158 	device_set_desc(dev, "Broadcom 2708 SDHCI controller");
159 	return (BUS_PROBE_DEFAULT);
160 }
161 
162 static int
163 bcm_sdhci_attach(device_t dev)
164 {
165 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
166 	int rid, err;
167 	phandle_t node;
168 	pcell_t cell;
169 	int default_freq;
170 
171 	sc->sc_dev = dev;
172 	sc->sc_req = NULL;
173 	err = 0;
174 
175 	default_freq = BCM2835_DEFAULT_SDHCI_FREQ;
176 	node = ofw_bus_get_node(sc->sc_dev);
177 	if ((OF_getprop(node, "clock-frequency", &cell, sizeof(cell))) > 0)
178 		default_freq = (int)fdt32_to_cpu(cell)/1000000;
179 
180 	dprintf("SDHCI frequency: %dMHz\n", default_freq);
181 
182 	mtx_init(&sc->sc_mtx, "bcm sdhci", "sdhci", MTX_DEF);
183 
184 	rid = 0;
185 	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
186 	    RF_ACTIVE);
187 	if (!sc->sc_mem_res) {
188 		device_printf(dev, "cannot allocate memory window\n");
189 		err = ENXIO;
190 		goto fail;
191 	}
192 
193 	sc->sc_bst = rman_get_bustag(sc->sc_mem_res);
194 	sc->sc_bsh = rman_get_bushandle(sc->sc_mem_res);
195 
196 	rid = 0;
197 	sc->sc_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
198 	    RF_ACTIVE);
199 	if (!sc->sc_irq_res) {
200 		device_printf(dev, "cannot allocate interrupt\n");
201 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
202 		err = ENXIO;
203 		goto fail;
204 	}
205 
206 	if (bus_setup_intr(dev, sc->sc_irq_res, INTR_TYPE_BIO | INTR_MPSAFE,
207 	    NULL, bcm_sdhci_intr, sc, &sc->sc_intrhand))
208 	{
209 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
210 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq_res);
211 		device_printf(dev, "cannot setup interrupt handler\n");
212 		err = ENXIO;
213 		goto fail;
214 	}
215 
216 	if (!bcm2835_sdhci_pio_mode)
217 		sc->sc_slot.opt = SDHCI_PLATFORM_TRANSFER;
218 
219 	sc->sc_slot.caps = SDHCI_CAN_VDD_330 | SDHCI_CAN_VDD_180;
220 	if (bcm2835_sdhci_hs)
221 		sc->sc_slot.caps |= SDHCI_CAN_DO_HISPD;
222 	sc->sc_slot.caps |= (default_freq << SDHCI_CLOCK_BASE_SHIFT);
223 	sc->sc_slot.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK
224 		| SDHCI_QUIRK_BROKEN_TIMEOUT_VAL
225 		| SDHCI_QUIRK_MISSING_CAPS;
226 
227 	sdhci_init_slot(dev, &sc->sc_slot, 0);
228 
229 	sc->sc_dma_ch = bcm_dma_allocate(BCM_DMA_CH_FAST1);
230 	if (sc->sc_dma_ch == BCM_DMA_CH_INVALID)
231 		sc->sc_dma_ch = bcm_dma_allocate(BCM_DMA_CH_FAST2);
232 	if (sc->sc_dma_ch == BCM_DMA_CH_INVALID)
233 		sc->sc_dma_ch = bcm_dma_allocate(BCM_DMA_CH_ANY);
234 	if (sc->sc_dma_ch == BCM_DMA_CH_INVALID)
235 		goto fail;
236 
237 	bcm_dma_setup_intr(sc->sc_dma_ch, bcm_sdhci_dma_intr, sc);
238 
239 	/* Allocate bus_dma resources. */
240 	err = bus_dma_tag_create(bus_get_dma_tag(dev),
241 	    1, 0, BUS_SPACE_MAXADDR_32BIT,
242 	    BUS_SPACE_MAXADDR, NULL, NULL,
243 	    BCM_SDHCI_BUFFER_SIZE, 1, BCM_SDHCI_BUFFER_SIZE,
244 	    BUS_DMA_ALLOCNOW, NULL, NULL,
245 	    &sc->sc_dma_tag);
246 
247 	if (err) {
248 		device_printf(dev, "failed allocate DMA tag");
249 		goto fail;
250 	}
251 
252 	err = bus_dmamap_create(sc->sc_dma_tag, 0, &sc->sc_dma_map);
253 	if (err) {
254 		device_printf(dev, "bus_dmamap_create failed\n");
255 		goto fail;
256 	}
257 
258 	sc->sc_sdhci_buffer_phys = BUS_SPACE_PHYSADDR(sc->sc_mem_res,
259 	    SDHCI_BUFFER);
260 
261 	bus_generic_probe(dev);
262 	bus_generic_attach(dev);
263 
264 	sdhci_start_slot(&sc->sc_slot);
265 
266 	return (0);
267 
268 fail:
269 	if (sc->sc_intrhand)
270 		bus_teardown_intr(dev, sc->sc_irq_res, sc->sc_intrhand);
271 	if (sc->sc_irq_res)
272 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq_res);
273 	if (sc->sc_mem_res)
274 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
275 
276 	return (err);
277 }
278 
279 static int
280 bcm_sdhci_detach(device_t dev)
281 {
282 
283 	return (EBUSY);
284 }
285 
286 static void
287 bcm_sdhci_intr(void *arg)
288 {
289 	struct bcm_sdhci_softc *sc = arg;
290 
291 	sdhci_generic_intr(&sc->sc_slot);
292 }
293 
294 static int
295 bcm_sdhci_get_ro(device_t bus, device_t child)
296 {
297 
298 	return (0);
299 }
300 
301 static inline uint32_t
302 RD4(struct bcm_sdhci_softc *sc, bus_size_t off)
303 {
304 	uint32_t val = bus_space_read_4(sc->sc_bst, sc->sc_bsh, off);
305 	return val;
306 }
307 
308 static inline void
309 WR4(struct bcm_sdhci_softc *sc, bus_size_t off, uint32_t val)
310 {
311 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, off, val);
312 
313 	if ((off != SDHCI_BUFFER && off != SDHCI_INT_STATUS && off != SDHCI_CLOCK_CONTROL))
314 	{
315 		int timeout = 100000;
316 		while (val != bus_space_read_4(sc->sc_bst, sc->sc_bsh, off)
317 		    && --timeout > 0)
318 			continue;
319 
320 		if (timeout <= 0)
321 			printf("sdhci_brcm: writing 0x%X to reg 0x%X "
322 				"always gives 0x%X\n",
323 				val, (uint32_t)off,
324 				bus_space_read_4(sc->sc_bst, sc->sc_bsh, off));
325 	}
326 }
327 
328 static uint8_t
329 bcm_sdhci_read_1(device_t dev, struct sdhci_slot *slot, bus_size_t off)
330 {
331 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
332 	uint32_t val = RD4(sc, off & ~3);
333 
334 	return ((val >> (off & 3)*8) & 0xff);
335 }
336 
337 static uint16_t
338 bcm_sdhci_read_2(device_t dev, struct sdhci_slot *slot, bus_size_t off)
339 {
340 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
341 	uint32_t val = RD4(sc, off & ~3);
342 
343 	return ((val >> (off & 3)*8) & 0xffff);
344 }
345 
346 static uint32_t
347 bcm_sdhci_read_4(device_t dev, struct sdhci_slot *slot, bus_size_t off)
348 {
349 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
350 
351 	return RD4(sc, off);
352 }
353 
354 static void
355 bcm_sdhci_read_multi_4(device_t dev, struct sdhci_slot *slot, bus_size_t off,
356     uint32_t *data, bus_size_t count)
357 {
358 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
359 
360 	bus_space_read_multi_4(sc->sc_bst, sc->sc_bsh, off, data, count);
361 }
362 
363 static void
364 bcm_sdhci_write_1(device_t dev, struct sdhci_slot *slot, bus_size_t off, uint8_t val)
365 {
366 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
367 	uint32_t val32 = RD4(sc, off & ~3);
368 	val32 &= ~(0xff << (off & 3)*8);
369 	val32 |= (val << (off & 3)*8);
370 	WR4(sc, off & ~3, val32);
371 }
372 
373 static void
374 bcm_sdhci_write_2(device_t dev, struct sdhci_slot *slot, bus_size_t off, uint16_t val)
375 {
376 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
377 	static uint32_t cmd_and_trandfer_mode;
378 	uint32_t val32;
379 	if (off == SDHCI_COMMAND_FLAGS)
380 		val32 = cmd_and_trandfer_mode;
381 	else
382 		val32 = RD4(sc, off & ~3);
383 	val32 &= ~(0xffff << (off & 3)*8);
384 	val32 |= (val << (off & 3)*8);
385 	if (off == SDHCI_TRANSFER_MODE)
386 		cmd_and_trandfer_mode = val32;
387 	else
388 		WR4(sc, off & ~3, val32);
389 }
390 
391 static void
392 bcm_sdhci_write_4(device_t dev, struct sdhci_slot *slot, bus_size_t off, uint32_t val)
393 {
394 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
395 	WR4(sc, off, val);
396 }
397 
398 static void
399 bcm_sdhci_write_multi_4(device_t dev, struct sdhci_slot *slot, bus_size_t off,
400     uint32_t *data, bus_size_t count)
401 {
402 	struct bcm_sdhci_softc *sc = device_get_softc(dev);
403 
404 	bus_space_write_multi_4(sc->sc_bst, sc->sc_bsh, off, data, count);
405 }
406 
407 static uint32_t
408 bcm_sdhci_min_freq(device_t dev, struct sdhci_slot *slot)
409 {
410 
411 	return bcm2835_sdhci_min_freq;
412 }
413 
414 static void
415 bcm_sdhci_dma_intr(int ch, void *arg)
416 {
417 	struct bcm_sdhci_softc *sc = (struct bcm_sdhci_softc *)arg;
418 	struct sdhci_slot *slot = &sc->sc_slot;
419 	uint32_t reg, mask;
420 	bus_addr_t pmem;
421 	vm_paddr_t pdst, psrc;
422 	size_t len;
423 	int left, sync_op;
424 
425 	mtx_lock(&slot->mtx);
426 
427 	len = bcm_dma_length(sc->sc_dma_ch);
428 	if (slot->curcmd->data->flags & MMC_DATA_READ) {
429 		sync_op = BUS_DMASYNC_POSTREAD;
430 		mask = SDHCI_INT_DATA_AVAIL;
431 	} else {
432 		sync_op = BUS_DMASYNC_POSTWRITE;
433 		mask = SDHCI_INT_SPACE_AVAIL;
434 	}
435 	bus_dmamap_sync(sc->sc_dma_tag, sc->sc_dma_map, sync_op);
436 	bus_dmamap_unload(sc->sc_dma_tag, sc->sc_dma_map);
437 
438 	slot->offset += len;
439 	sc->sc_dma_inuse = 0;
440 
441 	left = min(BCM_SDHCI_BUFFER_SIZE,
442 	    slot->curcmd->data->len - slot->offset);
443 
444 	/* DATA END? */
445 	reg = bcm_sdhci_read_4(slot->bus, slot, SDHCI_INT_STATUS);
446 
447 	if (reg & SDHCI_INT_DATA_END) {
448 		/* ACK for all outstanding interrupts */
449 		bcm_sdhci_write_4(slot->bus, slot, SDHCI_INT_STATUS, reg);
450 
451 		/* enable INT */
452 		slot->intmask |= SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL
453 		    | SDHCI_INT_DATA_END;
454 		bcm_sdhci_write_4(slot->bus, slot, SDHCI_SIGNAL_ENABLE,
455 		    slot->intmask);
456 
457 		/* finish this data */
458 		sdhci_finish_data(slot);
459 	}
460 	else {
461 		/* already available? */
462 		if (reg & mask) {
463 			sc->sc_dma_inuse = 1;
464 
465 			/* ACK for DATA_AVAIL or SPACE_AVAIL */
466 			bcm_sdhci_write_4(slot->bus, slot,
467 			    SDHCI_INT_STATUS, mask);
468 
469 			/* continue next DMA transfer */
470 			bus_dmamap_load(sc->sc_dma_tag, sc->sc_dma_map,
471 			    (uint8_t *)slot->curcmd->data->data +
472 			    slot->offset, left, bcm_dmamap_cb, &pmem, 0);
473 			if (slot->curcmd->data->flags & MMC_DATA_READ) {
474 				psrc = sc->sc_sdhci_buffer_phys;
475 				pdst = pmem;
476 				sync_op = BUS_DMASYNC_PREREAD;
477 			} else {
478 				psrc = pmem;
479 				pdst = sc->sc_sdhci_buffer_phys;
480 				sync_op = BUS_DMASYNC_PREWRITE;
481 			}
482 			bus_dmamap_sync(sc->sc_dma_tag, sc->sc_dma_map, sync_op);
483 			if (bcm_dma_start(sc->sc_dma_ch, psrc, pdst, left)) {
484 				/* XXX stop xfer, other error recovery? */
485 				device_printf(sc->sc_dev, "failed DMA start\n");
486 			}
487 		} else {
488 			/* wait for next data by INT */
489 
490 			/* enable INT */
491 			slot->intmask |= SDHCI_INT_DATA_AVAIL |
492 			    SDHCI_INT_SPACE_AVAIL | SDHCI_INT_DATA_END;
493 			bcm_sdhci_write_4(slot->bus, slot, SDHCI_SIGNAL_ENABLE,
494 			    slot->intmask);
495 		}
496 	}
497 
498 	mtx_unlock(&slot->mtx);
499 }
500 
501 static void
502 bcm_sdhci_read_dma(struct sdhci_slot *slot)
503 {
504 	struct bcm_sdhci_softc *sc = device_get_softc(slot->bus);
505 	size_t left;
506 	bus_addr_t paddr;
507 
508 	if (sc->sc_dma_inuse) {
509 		device_printf(sc->sc_dev, "DMA in use\n");
510 		return;
511 	}
512 
513 	sc->sc_dma_inuse = 1;
514 
515 	left = min(BCM_SDHCI_BUFFER_SIZE,
516 	    slot->curcmd->data->len - slot->offset);
517 
518 	KASSERT((left & 3) == 0,
519 	    ("%s: len = %d, not word-aligned", __func__, left));
520 
521 	bcm_dma_setup_src(sc->sc_dma_ch, BCM_DMA_DREQ_EMMC,
522 	    BCM_DMA_SAME_ADDR, BCM_DMA_32BIT);
523 	bcm_dma_setup_dst(sc->sc_dma_ch, BCM_DMA_DREQ_NONE,
524 	    BCM_DMA_INC_ADDR,
525 	    (left & 0xf) ? BCM_DMA_32BIT : BCM_DMA_128BIT);
526 
527 	bus_dmamap_load(sc->sc_dma_tag, sc->sc_dma_map,
528 	    (uint8_t *)slot->curcmd->data->data + slot->offset, left,
529 	    bcm_dmamap_cb, &paddr, 0);
530 
531 	bus_dmamap_sync(sc->sc_dma_tag, sc->sc_dma_map,
532 	    BUS_DMASYNC_PREREAD);
533 
534 	/* DMA start */
535 	if (bcm_dma_start(sc->sc_dma_ch, sc->sc_sdhci_buffer_phys,
536 	    paddr, left) != 0)
537 		device_printf(sc->sc_dev, "failed DMA start\n");
538 }
539 
540 static void
541 bcm_sdhci_write_dma(struct sdhci_slot *slot)
542 {
543 	struct bcm_sdhci_softc *sc = device_get_softc(slot->bus);
544 	size_t left;
545 	bus_addr_t paddr;
546 
547 	if (sc->sc_dma_inuse) {
548 		device_printf(sc->sc_dev, "DMA in use\n");
549 		return;
550 	}
551 
552 	sc->sc_dma_inuse = 1;
553 
554 	left = min(BCM_SDHCI_BUFFER_SIZE,
555 	    slot->curcmd->data->len - slot->offset);
556 
557 	KASSERT((left & 3) == 0,
558 	    ("%s: len = %d, not word-aligned", __func__, left));
559 
560 	bus_dmamap_load(sc->sc_dma_tag, sc->sc_dma_map,
561 	    (uint8_t *)slot->curcmd->data->data + slot->offset, left,
562 	    bcm_dmamap_cb, &paddr, 0);
563 
564 	bcm_dma_setup_src(sc->sc_dma_ch, BCM_DMA_DREQ_NONE,
565 	    BCM_DMA_INC_ADDR,
566 	    (left & 0xf) ? BCM_DMA_32BIT : BCM_DMA_128BIT);
567 	bcm_dma_setup_dst(sc->sc_dma_ch, BCM_DMA_DREQ_EMMC,
568 	    BCM_DMA_SAME_ADDR, BCM_DMA_32BIT);
569 
570 	bus_dmamap_sync(sc->sc_dma_tag, sc->sc_dma_map,
571 	    BUS_DMASYNC_PREWRITE);
572 
573 	/* DMA start */
574 	if (bcm_dma_start(sc->sc_dma_ch, paddr,
575 	    sc->sc_sdhci_buffer_phys, left) != 0)
576 		device_printf(sc->sc_dev, "failed DMA start\n");
577 }
578 
579 static int
580 bcm_sdhci_will_handle_transfer(device_t dev, struct sdhci_slot *slot)
581 {
582 	size_t left;
583 
584 	/*
585 	 * Do not use DMA for transfers less than block size or with a length
586 	 * that is not a multiple of four.
587 	 */
588 	left = min(BCM_DMA_BLOCK_SIZE,
589 	    slot->curcmd->data->len - slot->offset);
590 	if (left < BCM_DMA_BLOCK_SIZE)
591 		return (0);
592 	if (left & 0x03)
593 		return (0);
594 
595 	return (1);
596 }
597 
598 static void
599 bcm_sdhci_start_transfer(device_t dev, struct sdhci_slot *slot,
600     uint32_t *intmask)
601 {
602 
603 	/* Disable INT */
604 	slot->intmask &= ~(SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL | SDHCI_INT_DATA_END);
605 	bcm_sdhci_write_4(dev, slot, SDHCI_SIGNAL_ENABLE, slot->intmask);
606 
607 	/* DMA transfer FIFO 1KB */
608 	if (slot->curcmd->data->flags & MMC_DATA_READ)
609 		bcm_sdhci_read_dma(slot);
610 	else
611 		bcm_sdhci_write_dma(slot);
612 }
613 
614 static void
615 bcm_sdhci_finish_transfer(device_t dev, struct sdhci_slot *slot)
616 {
617 
618 	sdhci_finish_data(slot);
619 }
620 
621 static device_method_t bcm_sdhci_methods[] = {
622 	/* Device interface */
623 	DEVMETHOD(device_probe,		bcm_sdhci_probe),
624 	DEVMETHOD(device_attach,	bcm_sdhci_attach),
625 	DEVMETHOD(device_detach,	bcm_sdhci_detach),
626 
627 	/* Bus interface */
628 	DEVMETHOD(bus_read_ivar,	sdhci_generic_read_ivar),
629 	DEVMETHOD(bus_write_ivar,	sdhci_generic_write_ivar),
630 	DEVMETHOD(bus_print_child,	bus_generic_print_child),
631 
632 	/* MMC bridge interface */
633 	DEVMETHOD(mmcbr_update_ios,	sdhci_generic_update_ios),
634 	DEVMETHOD(mmcbr_request,	sdhci_generic_request),
635 	DEVMETHOD(mmcbr_get_ro,		bcm_sdhci_get_ro),
636 	DEVMETHOD(mmcbr_acquire_host,	sdhci_generic_acquire_host),
637 	DEVMETHOD(mmcbr_release_host,	sdhci_generic_release_host),
638 
639 	DEVMETHOD(sdhci_min_freq,	bcm_sdhci_min_freq),
640 	/* Platform transfer methods */
641 	DEVMETHOD(sdhci_platform_will_handle,		bcm_sdhci_will_handle_transfer),
642 	DEVMETHOD(sdhci_platform_start_transfer,	bcm_sdhci_start_transfer),
643 	DEVMETHOD(sdhci_platform_finish_transfer,	bcm_sdhci_finish_transfer),
644 	/* SDHCI registers accessors */
645 	DEVMETHOD(sdhci_read_1,		bcm_sdhci_read_1),
646 	DEVMETHOD(sdhci_read_2,		bcm_sdhci_read_2),
647 	DEVMETHOD(sdhci_read_4,		bcm_sdhci_read_4),
648 	DEVMETHOD(sdhci_read_multi_4,	bcm_sdhci_read_multi_4),
649 	DEVMETHOD(sdhci_write_1,	bcm_sdhci_write_1),
650 	DEVMETHOD(sdhci_write_2,	bcm_sdhci_write_2),
651 	DEVMETHOD(sdhci_write_4,	bcm_sdhci_write_4),
652 	DEVMETHOD(sdhci_write_multi_4,	bcm_sdhci_write_multi_4),
653 
654 	{ 0, 0 }
655 };
656 
657 static devclass_t bcm_sdhci_devclass;
658 
659 static driver_t bcm_sdhci_driver = {
660 	"sdhci_bcm",
661 	bcm_sdhci_methods,
662 	sizeof(struct bcm_sdhci_softc),
663 };
664 
665 DRIVER_MODULE(sdhci_bcm, simplebus, bcm_sdhci_driver, bcm_sdhci_devclass, 0, 0);
666 MODULE_DEPEND(sdhci_bcm, sdhci, 1, 1, 1);
667