xref: /freebsd/sys/dev/spibus/controller/allwinner/aw_spi.c (revision 5b56413d04e608379c9a306373554a8e4d321bc0)
1 /*-
2  * Copyright (c) 2018 Emmanuel Vadot <manu@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
18  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
20  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
21  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/param.h>
27 #include <sys/systm.h>
28 #include <sys/bus.h>
29 #include <sys/kernel.h>
30 #include <sys/lock.h>
31 #include <sys/module.h>
32 #include <sys/mutex.h>
33 #include <sys/rman.h>
34 #include <sys/resource.h>
35 #include <machine/bus.h>
36 
37 #include <dev/ofw/ofw_bus.h>
38 #include <dev/ofw/ofw_bus_subr.h>
39 
40 #include <dev/spibus/spi.h>
41 #include <dev/spibus/spibusvar.h>
42 
43 #include <dev/clk/clk.h>
44 #include <dev/hwreset/hwreset.h>
45 
46 #include "spibus_if.h"
47 
48 #define	AW_SPI_GCR		0x04		/* Global Control Register */
49 #define	 AW_SPI_GCR_EN		(1 << 0)	/* ENable */
50 #define	 AW_SPI_GCR_MODE_MASTER	(1 << 1)	/* 1 = Master, 0 = Slave */
51 #define	 AW_SPI_GCR_TP_EN	(1 << 7)	/* 1 = Stop transmit when FIFO is full */
52 #define	 AW_SPI_GCR_SRST	(1 << 31)	/* Soft Reset */
53 
54 #define	AW_SPI_TCR		0x08		/* Transfer Control register */
55 #define	 AW_SPI_TCR_XCH		(1 << 31)	/* Initiate transfer */
56 #define	 AW_SPI_TCR_SDDM	(1 << 14)	/* Sending Delay Data Mode */
57 #define	 AW_SPI_TCR_SDM		(1 << 13)	/* Master Sample Data Mode */
58 #define	 AW_SPI_TCR_FBS		(1 << 12)	/* First Transmit Bit Select (1 == LSB) */
59 #define	 AW_SPI_TCR_SDC		(1 << 11)	/* Master Sample Data Control */
60 #define	 AW_SPI_TCR_RPSM	(1 << 10)	/* Rapid Mode Select */
61 #define	 AW_SPI_TCR_DDB		(1 << 9)	/* Dummy Burst Type */
62 #define	 AW_SPI_TCR_SSSEL_MASK	0x30		/* Chip select */
63 #define	 AW_SPI_TCR_SSSEL_SHIFT	4
64 #define	 AW_SPI_TCR_SS_LEVEL	(1 << 7)	/* 1 == CS High */
65 #define	 AW_SPI_TCR_SS_OWNER	(1 << 6)	/* 1 == Software controlled */
66 #define	 AW_SPI_TCR_SPOL	(1 << 2)	/* 1 == Active low */
67 #define	 AW_SPI_TCR_CPOL	(1 << 1)	/* 1 == Active low */
68 #define	 AW_SPI_TCR_CPHA	(1 << 0)	/* 1 == Phase 1 */
69 
70 #define	AW_SPI_IER		0x10		/* Interrupt Control Register */
71 #define	 AW_SPI_IER_SS		(1 << 13)	/* Chip select went from valid to invalid */
72 #define	 AW_SPI_IER_TC		(1 << 12)	/* Transfer complete */
73 #define	 AW_SPI_IER_TF_UDR	(1 << 11)	/* TXFIFO underrun */
74 #define	 AW_SPI_IER_TF_OVF	(1 << 10)	/* TXFIFO overrun */
75 #define	 AW_SPI_IER_RF_UDR	(1 << 9)	/* RXFIFO underrun */
76 #define	 AW_SPI_IER_RF_OVF	(1 << 8)	/* RXFIFO overrun */
77 #define	 AW_SPI_IER_TF_FULL	(1 << 6)	/* TXFIFO Full */
78 #define	 AW_SPI_IER_TF_EMP	(1 << 5)	/* TXFIFO Empty */
79 #define	 AW_SPI_IER_TF_ERQ	(1 << 4)	/* TXFIFO Empty Request */
80 #define	 AW_SPI_IER_RF_FULL	(1 << 2)	/* RXFIFO Full */
81 #define	 AW_SPI_IER_RF_EMP	(1 << 1)	/* RXFIFO Empty */
82 #define	 AW_SPI_IER_RF_RDY	(1 << 0)	/* RXFIFO Ready Request */
83 
84 #define	AW_SPI_ISR		0x14		/* Interrupt Status Register */
85 
86 #define	AW_SPI_FCR			0x18		/* FIFO Control Register */
87 #define	 AW_SPI_FCR_TX_RST		(1 << 31)	/* Reset TX FIFO */
88 #define	 AW_SPI_FCR_TX_TRIG_MASK	0xFF0000	/* TX FIFO Trigger level */
89 #define	 AW_SPI_FCR_TX_TRIG_SHIFT	16
90 #define	 AW_SPI_FCR_RX_RST	(1 << 15)		/* Reset RX FIFO */
91 #define	 AW_SPI_FCR_RX_TRIG_MASK	0xFF		/* RX FIFO Trigger level */
92 #define	 AW_SPI_FCR_RX_TRIG_SHIFT	0
93 
94 #define	AW_SPI_FSR	0x1C			/* FIFO Status Register */
95 #define	 AW_SPI_FSR_TB_WR		(1 << 31)
96 #define	 AW_SPI_FSR_TB_CNT_MASK		0x70000000
97 #define	 AW_SPI_FSR_TB_CNT_SHIFT	28
98 #define	 AW_SPI_FSR_TF_CNT_MASK		0xFF0000
99 #define	 AW_SPI_FSR_TF_CNT_SHIFT	16
100 #define	 AW_SPI_FSR_RB_WR		(1 << 15)
101 #define	 AW_SPI_FSR_RB_CNT_MASK		0x7000
102 #define	 AW_SPI_FSR_RB_CNT_SHIFT	12
103 #define	 AW_SPI_FSR_RF_CNT_MASK		0xFF
104 #define	 AW_SPI_FSR_RF_CNT_SHIFT	0
105 
106 #define	AW_SPI_WCR	0x20	/* Wait Clock Counter Register */
107 
108 #define	AW_SPI_CCR	0x24		/* Clock Rate Control Register */
109 #define	 AW_SPI_CCR_DRS	(1 << 12)	/* Clock divider select */
110 #define	 AW_SPI_CCR_CDR1_MASK	0xF00
111 #define	 AW_SPI_CCR_CDR1_SHIFT	8
112 #define	 AW_SPI_CCR_CDR2_MASK	0xFF
113 #define	 AW_SPI_CCR_CDR2_SHIFT	0
114 
115 #define	AW_SPI_MBC	0x30	/* Burst Counter Register */
116 #define	AW_SPI_MTC	0x34	/* Transmit Counter Register */
117 #define	AW_SPI_BCC	0x38	/* Burst Control Register */
118 #define	AW_SPI_MDMA_CTL	0x88	/* Normal DMA Control Register */
119 #define	AW_SPI_TXD	0x200	/* TX Data Register */
120 #define	AW_SPI_RDX	0x300	/* RX Data Register */
121 
122 #define	AW_SPI_MAX_CS		4
123 #define	AW_SPI_FIFO_SIZE	64
124 
125 static struct ofw_compat_data compat_data[] = {
126 	{ "allwinner,sun8i-h3-spi",		1 },
127 	{ NULL,					0 }
128 };
129 
130 static struct resource_spec aw_spi_spec[] = {
131 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
132 	{ SYS_RES_IRQ,		0,	RF_ACTIVE | RF_SHAREABLE },
133 	{ -1, 0 }
134 };
135 
136 struct aw_spi_softc {
137 	device_t	dev;
138 	device_t	spibus;
139 	struct resource	*res[2];
140 	struct mtx	mtx;
141 	clk_t		clk_ahb;
142 	clk_t		clk_mod;
143 	uint64_t	mod_freq;
144 	hwreset_t	rst_ahb;
145 	void *		intrhand;
146 	int		transfer;
147 
148 	uint8_t		*rxbuf;
149 	uint32_t	rxcnt;
150 	uint8_t		*txbuf;
151 	uint32_t	txcnt;
152 	uint32_t	txlen;
153 	uint32_t	rxlen;
154 };
155 
156 #define	AW_SPI_LOCK(sc)			mtx_lock(&(sc)->mtx)
157 #define	AW_SPI_UNLOCK(sc)		mtx_unlock(&(sc)->mtx)
158 #define	AW_SPI_ASSERT_LOCKED(sc)	mtx_assert(&(sc)->mtx, MA_OWNED)
159 #define	AW_SPI_READ_1(sc, reg)		bus_read_1((sc)->res[0], (reg))
160 #define	AW_SPI_WRITE_1(sc, reg, val)	bus_write_1((sc)->res[0], (reg), (val))
161 #define	AW_SPI_READ_4(sc, reg)		bus_read_4((sc)->res[0], (reg))
162 #define	AW_SPI_WRITE_4(sc, reg, val)	bus_write_4((sc)->res[0], (reg), (val))
163 
164 static int aw_spi_probe(device_t dev);
165 static int aw_spi_attach(device_t dev);
166 static int aw_spi_detach(device_t dev);
167 static int aw_spi_intr(void *arg);
168 
169 static int
170 aw_spi_probe(device_t dev)
171 {
172 	if (!ofw_bus_status_okay(dev))
173 		return (ENXIO);
174 
175 	if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
176 		return (ENXIO);
177 
178 	device_set_desc(dev, "Allwinner SPI");
179 	return (BUS_PROBE_DEFAULT);
180 }
181 
182 static int
183 aw_spi_attach(device_t dev)
184 {
185 	struct aw_spi_softc *sc;
186 	int error;
187 
188 	sc = device_get_softc(dev);
189 	sc->dev = dev;
190 
191 	mtx_init(&sc->mtx, device_get_nameunit(dev), NULL, MTX_DEF);
192 
193 	if (bus_alloc_resources(dev, aw_spi_spec, sc->res) != 0) {
194 		device_printf(dev, "cannot allocate resources for device\n");
195 		error = ENXIO;
196 		goto fail;
197 	}
198 
199 	if (bus_setup_intr(dev, sc->res[1],
200 	    INTR_TYPE_MISC | INTR_MPSAFE, aw_spi_intr, NULL, sc,
201 	    &sc->intrhand)) {
202 		bus_release_resources(dev, aw_spi_spec, sc->res);
203 		device_printf(dev, "cannot setup interrupt handler\n");
204 		return (ENXIO);
205 	}
206 
207 	/* De-assert reset */
208 	if (hwreset_get_by_ofw_idx(dev, 0, 0, &sc->rst_ahb) == 0) {
209 		error = hwreset_deassert(sc->rst_ahb);
210 		if (error != 0) {
211 			device_printf(dev, "cannot de-assert reset\n");
212 			goto fail;
213 		}
214 	}
215 
216 	/* Activate the module clock. */
217 	error = clk_get_by_ofw_name(dev, 0, "ahb", &sc->clk_ahb);
218 	if (error != 0) {
219 		device_printf(dev, "cannot get ahb clock\n");
220 		goto fail;
221 	}
222 	error = clk_get_by_ofw_name(dev, 0, "mod", &sc->clk_mod);
223 	if (error != 0) {
224 		device_printf(dev, "cannot get mod clock\n");
225 		goto fail;
226 	}
227 	error = clk_enable(sc->clk_ahb);
228 	if (error != 0) {
229 		device_printf(dev, "cannot enable ahb clock\n");
230 		goto fail;
231 	}
232 	error = clk_enable(sc->clk_mod);
233 	if (error != 0) {
234 		device_printf(dev, "cannot enable mod clock\n");
235 		goto fail;
236 	}
237 
238 	sc->spibus = device_add_child(dev, "spibus", DEVICE_UNIT_ANY);
239 
240 	return (bus_generic_attach(dev));
241 
242 fail:
243 	aw_spi_detach(dev);
244 	return (error);
245 }
246 
247 static int
248 aw_spi_detach(device_t dev)
249 {
250 	struct aw_spi_softc *sc;
251 
252 	sc = device_get_softc(dev);
253 
254 	bus_generic_detach(sc->dev);
255 	if (sc->spibus != NULL)
256 		device_delete_child(dev, sc->spibus);
257 
258 	if (sc->clk_mod != NULL)
259 		clk_release(sc->clk_mod);
260 	if (sc->clk_ahb)
261 		clk_release(sc->clk_ahb);
262 	if (sc->rst_ahb)
263 		hwreset_assert(sc->rst_ahb);
264 
265 	if (sc->intrhand != NULL)
266 		bus_teardown_intr(sc->dev, sc->res[1], sc->intrhand);
267 
268 	bus_release_resources(dev, aw_spi_spec, sc->res);
269 	mtx_destroy(&sc->mtx);
270 
271 	return (0);
272 }
273 
274 static phandle_t
275 aw_spi_get_node(device_t bus, device_t dev)
276 {
277 
278 	return ofw_bus_get_node(bus);
279 }
280 
281 static void
282 aw_spi_setup_mode(struct aw_spi_softc *sc, uint32_t mode)
283 {
284 	uint32_t reg;
285 
286 	/* We only support master mode */
287 	reg = AW_SPI_READ_4(sc, AW_SPI_GCR);
288 	reg |= AW_SPI_GCR_MODE_MASTER;
289 	AW_SPI_WRITE_4(sc, AW_SPI_GCR, reg);
290 
291 	/* Setup the modes */
292 	reg = AW_SPI_READ_4(sc, AW_SPI_TCR);
293 	if (mode & SPIBUS_MODE_CPHA)
294 		reg |= AW_SPI_TCR_CPHA;
295 	if (mode & SPIBUS_MODE_CPOL)
296 		reg |= AW_SPI_TCR_CPOL;
297 
298 	AW_SPI_WRITE_4(sc, AW_SPI_TCR, reg);
299 }
300 
301 static void
302 aw_spi_setup_cs(struct aw_spi_softc *sc, uint32_t cs, bool low)
303 {
304 	uint32_t reg;
305 
306 	/* Setup CS */
307 	reg = AW_SPI_READ_4(sc, AW_SPI_TCR);
308 	reg &= ~(AW_SPI_TCR_SSSEL_MASK);
309 	reg |= cs << AW_SPI_TCR_SSSEL_SHIFT;
310 	reg |= AW_SPI_TCR_SS_OWNER;
311 	if (low)
312 		reg &= ~(AW_SPI_TCR_SS_LEVEL);
313 	else
314 		reg |= AW_SPI_TCR_SS_LEVEL;
315 
316 	AW_SPI_WRITE_4(sc, AW_SPI_TCR, reg);
317 }
318 
319 static uint64_t
320 aw_spi_clock_test_cdr1(struct aw_spi_softc *sc, uint64_t clock, uint32_t *ccr)
321 {
322 	uint64_t cur, best = 0;
323 	int i, max, best_div;
324 
325 	max = AW_SPI_CCR_CDR1_MASK >> AW_SPI_CCR_CDR1_SHIFT;
326 	for (i = 0; i < max; i++) {
327 		cur = sc->mod_freq / (1 << i);
328 		if ((clock - cur) < (clock - best)) {
329 			best = cur;
330 			best_div = i;
331 		}
332 	}
333 
334 	*ccr = (best_div << AW_SPI_CCR_CDR1_SHIFT);
335 	return (best);
336 }
337 
338 static uint64_t
339 aw_spi_clock_test_cdr2(struct aw_spi_softc *sc, uint64_t clock, uint32_t *ccr)
340 {
341 	uint64_t cur, best = 0;
342 	int i, max, best_div;
343 
344 	max = ((AW_SPI_CCR_CDR2_MASK) >> AW_SPI_CCR_CDR2_SHIFT);
345 	for (i = 0; i < max; i++) {
346 		cur = sc->mod_freq / (2 * i + 1);
347 		if ((clock - cur) < (clock - best)) {
348 			best = cur;
349 			best_div = i;
350 		}
351 	}
352 
353 	*ccr = AW_SPI_CCR_DRS | (best_div << AW_SPI_CCR_CDR2_SHIFT);
354 	return (best);
355 }
356 
357 static void
358 aw_spi_setup_clock(struct aw_spi_softc *sc, uint64_t clock)
359 {
360 	uint64_t best_ccr1, best_ccr2;
361 	uint32_t ccr, ccr1, ccr2;
362 
363 	best_ccr1 = aw_spi_clock_test_cdr1(sc, clock, &ccr1);
364 	best_ccr2 = aw_spi_clock_test_cdr2(sc, clock, &ccr2);
365 
366 	if (best_ccr1 == clock) {
367 		ccr = ccr1;
368 	} else if (best_ccr2 == clock) {
369 		ccr = ccr2;
370 	} else {
371 		if ((clock - best_ccr1) < (clock - best_ccr2))
372 			ccr = ccr1;
373 		else
374 			ccr = ccr2;
375 	}
376 
377 	AW_SPI_WRITE_4(sc, AW_SPI_CCR, ccr);
378 }
379 
380 static inline void
381 aw_spi_fill_txfifo(struct aw_spi_softc *sc)
382 {
383 	uint32_t reg, txcnt;
384 	int i;
385 
386 	if (sc->txcnt == sc->txlen)
387 		return;
388 
389 	reg = AW_SPI_READ_4(sc, AW_SPI_FSR);
390 	reg &= AW_SPI_FSR_TF_CNT_MASK;
391 	txcnt = reg >> AW_SPI_FSR_TF_CNT_SHIFT;
392 
393 	for (i = 0; i < (AW_SPI_FIFO_SIZE - txcnt); i++) {
394 		AW_SPI_WRITE_1(sc, AW_SPI_TXD, sc->txbuf[sc->txcnt++]);
395 		if (sc->txcnt == sc->txlen)
396 			break;
397 	}
398 
399 	return;
400 }
401 
402 static inline void
403 aw_spi_read_rxfifo(struct aw_spi_softc *sc)
404 {
405 	uint32_t reg;
406 	uint8_t val;
407 	int i;
408 
409 	if (sc->rxcnt == sc->rxlen)
410 		return;
411 
412 	reg = AW_SPI_READ_4(sc, AW_SPI_FSR);
413 	reg = (reg & AW_SPI_FSR_RF_CNT_MASK) >> AW_SPI_FSR_RF_CNT_SHIFT;
414 
415 	for (i = 0; i < reg; i++) {
416 		val = AW_SPI_READ_1(sc, AW_SPI_RDX);
417 		if (sc->rxcnt < sc->rxlen)
418 			sc->rxbuf[sc->rxcnt++] = val;
419 	}
420 }
421 
422 static int
423 aw_spi_intr(void *arg)
424 {
425 	struct aw_spi_softc *sc;
426 	uint32_t intr;
427 
428 	sc = (struct aw_spi_softc *)arg;
429 
430 	intr = AW_SPI_READ_4(sc, AW_SPI_ISR);
431 
432 	if (intr & AW_SPI_IER_RF_RDY)
433 		aw_spi_read_rxfifo(sc);
434 
435 	if (intr & AW_SPI_IER_TF_ERQ) {
436 		aw_spi_fill_txfifo(sc);
437 
438 		/*
439 		 * If we don't have anything else to write
440 		 * disable TXFifo interrupts
441 		 */
442 		if (sc->txcnt == sc->txlen)
443 			AW_SPI_WRITE_4(sc, AW_SPI_IER, AW_SPI_IER_TC |
444 			    AW_SPI_IER_RF_RDY);
445 	}
446 
447 	if (intr & AW_SPI_IER_TC) {
448 		/* read the rest of the data from the fifo */
449 		aw_spi_read_rxfifo(sc);
450 
451 		/* Disable the interrupts */
452 		AW_SPI_WRITE_4(sc, AW_SPI_IER, 0);
453 		sc->transfer = 0;
454 		wakeup(sc);
455 	}
456 
457 	/* Clear Interrupts */
458 	AW_SPI_WRITE_4(sc, AW_SPI_ISR, intr);
459 	return (intr != 0 ? FILTER_HANDLED : FILTER_STRAY);
460 }
461 
462 static int
463 aw_spi_xfer(struct aw_spi_softc *sc, void *rxbuf, void *txbuf, uint32_t txlen, uint32_t rxlen)
464 {
465 	uint32_t reg;
466 	int error = 0, timeout;
467 
468 	sc->rxbuf = rxbuf;
469 	sc->rxcnt = 0;
470 	sc->txbuf = txbuf;
471 	sc->txcnt = 0;
472 	sc->txlen = txlen;
473 	sc->rxlen = rxlen;
474 
475 	/* Reset the FIFOs */
476 	AW_SPI_WRITE_4(sc, AW_SPI_FCR, AW_SPI_FCR_TX_RST | AW_SPI_FCR_RX_RST);
477 
478 	for (timeout = 1000; timeout > 0; timeout--) {
479 		reg = AW_SPI_READ_4(sc, AW_SPI_FCR);
480 		if (reg == 0)
481 			break;
482 	}
483 	if (timeout == 0) {
484 		device_printf(sc->dev, "Cannot reset the FIFOs\n");
485 		return (EIO);
486 	}
487 
488 	/*
489 	 * Set the TX FIFO threshold to 3/4-th the size and
490 	 * the RX FIFO one to 1/4-th.
491 	 */
492 	AW_SPI_WRITE_4(sc, AW_SPI_FCR,
493 	    ((3 * AW_SPI_FIFO_SIZE / 4) << AW_SPI_FCR_TX_TRIG_SHIFT) |
494 	    ((AW_SPI_FIFO_SIZE / 4) << AW_SPI_FCR_RX_TRIG_SHIFT));
495 
496 	/* Write the counters */
497 	AW_SPI_WRITE_4(sc, AW_SPI_MBC, txlen);
498 	AW_SPI_WRITE_4(sc, AW_SPI_MTC, txlen);
499 	AW_SPI_WRITE_4(sc, AW_SPI_BCC, txlen);
500 
501 	/* First fill */
502 	aw_spi_fill_txfifo(sc);
503 
504 	/* Start transmit */
505 	reg = AW_SPI_READ_4(sc, AW_SPI_TCR);
506 	reg |= AW_SPI_TCR_XCH;
507 	AW_SPI_WRITE_4(sc, AW_SPI_TCR, reg);
508 
509 	/*
510 	 * Enable interrupts for :
511 	 * Transmit complete
512 	 * TX Fifo is below its trigger threshold
513 	 * RX Fifo is above its trigger threshold
514 	 */
515 	AW_SPI_WRITE_4(sc, AW_SPI_IER, AW_SPI_IER_TC |
516 	    AW_SPI_IER_TF_ERQ | AW_SPI_IER_RF_RDY);
517 
518 	sc->transfer = 1;
519 
520 	while (error == 0 && sc->transfer != 0)
521 		error = msleep(sc, &sc->mtx, 0, "aw_spi", 10 * hz);
522 
523 	return (0);
524 }
525 
526 static int
527 aw_spi_transfer(device_t dev, device_t child, struct spi_command *cmd)
528 {
529 	struct aw_spi_softc *sc;
530 	uint32_t cs, mode, clock, reg;
531 	int err = 0;
532 
533 	sc = device_get_softc(dev);
534 
535 	spibus_get_cs(child, &cs);
536 	spibus_get_clock(child, &clock);
537 	spibus_get_mode(child, &mode);
538 
539 	/* The minimum divider is 2 so set the clock at twice the needed speed */
540 	clk_set_freq(sc->clk_mod, 2 * clock, CLK_SET_ROUND_DOWN);
541 	clk_get_freq(sc->clk_mod, &sc->mod_freq);
542 	if (cs >= AW_SPI_MAX_CS) {
543 		device_printf(dev, "Invalid cs %d\n", cs);
544 		return (EINVAL);
545 	}
546 
547 	mtx_lock(&sc->mtx);
548 
549 	/* Enable and reset the module */
550 	reg = AW_SPI_READ_4(sc, AW_SPI_GCR);
551 	reg |= AW_SPI_GCR_EN | AW_SPI_GCR_SRST;
552 	AW_SPI_WRITE_4(sc, AW_SPI_GCR, reg);
553 
554 	/* Setup clock, CS and mode */
555 	aw_spi_setup_clock(sc, clock);
556 	aw_spi_setup_mode(sc, mode);
557 	if (cs & SPIBUS_CS_HIGH)
558 		aw_spi_setup_cs(sc, cs, false);
559 	else
560 		aw_spi_setup_cs(sc, cs, true);
561 
562 	/* xfer */
563 	err = 0;
564 	if (cmd->tx_cmd_sz > 0)
565 		err = aw_spi_xfer(sc, cmd->rx_cmd, cmd->tx_cmd,
566 		    cmd->tx_cmd_sz, cmd->rx_cmd_sz);
567 	if (cmd->tx_data_sz > 0 && err == 0)
568 		err = aw_spi_xfer(sc, cmd->rx_data, cmd->tx_data,
569 		    cmd->tx_data_sz, cmd->rx_data_sz);
570 
571 	if (cs & SPIBUS_CS_HIGH)
572 		aw_spi_setup_cs(sc, cs, true);
573 	else
574 		aw_spi_setup_cs(sc, cs, false);
575 
576 	/* Disable the module */
577 	reg = AW_SPI_READ_4(sc, AW_SPI_GCR);
578 	reg &= ~AW_SPI_GCR_EN;
579 	AW_SPI_WRITE_4(sc, AW_SPI_GCR, reg);
580 
581 	mtx_unlock(&sc->mtx);
582 
583 	return (err);
584 }
585 
586 static device_method_t aw_spi_methods[] = {
587 	/* Device interface */
588 	DEVMETHOD(device_probe,		aw_spi_probe),
589 	DEVMETHOD(device_attach,	aw_spi_attach),
590 	DEVMETHOD(device_detach,	aw_spi_detach),
591 
592         /* spibus_if  */
593 	DEVMETHOD(spibus_transfer,	aw_spi_transfer),
594 
595         /* ofw_bus_if */
596 	DEVMETHOD(ofw_bus_get_node,	aw_spi_get_node),
597 
598 	DEVMETHOD_END
599 };
600 
601 static driver_t aw_spi_driver = {
602 	"aw_spi",
603 	aw_spi_methods,
604 	sizeof(struct aw_spi_softc),
605 };
606 
607 DRIVER_MODULE(aw_spi, simplebus, aw_spi_driver, 0, 0);
608 DRIVER_MODULE(ofw_spibus, aw_spi, ofw_spibus_driver, 0, 0);
609 MODULE_DEPEND(aw_spi, ofw_spibus, 1, 1, 1);
610 SIMPLEBUS_PNP_INFO(compat_data);
611