xref: /freebsd/sys/arm/xilinx/zy7_spi.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 /*-
2  * Copyright (c) 2018 Thomas Skibo <thomasskibo@yahoo.com>
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/param.h>
28 #include <sys/systm.h>
29 #include <sys/conf.h>
30 #include <sys/kernel.h>
31 #include <sys/module.h>
32 #include <sys/sysctl.h>
33 #include <sys/lock.h>
34 #include <sys/mutex.h>
35 #include <sys/resource.h>
36 #include <sys/rman.h>
37 #include <sys/uio.h>
38 
39 #include <machine/bus.h>
40 #include <machine/resource.h>
41 #include <machine/stdarg.h>
42 
43 #include <dev/fdt/fdt_common.h>
44 #include <dev/ofw/ofw_bus.h>
45 #include <dev/ofw/ofw_bus_subr.h>
46 
47 #include <dev/spibus/spi.h>
48 #include <dev/spibus/spibusvar.h>
49 
50 #include "spibus_if.h"
51 
52 static struct ofw_compat_data compat_data[] = {
53 	{"xlnx,zy7_spi",		1},
54 	{"xlnx,zynq-spi-1.0",		1},
55 	{"cdns,spi-r1p6",		1},
56 	{NULL,				0}
57 };
58 
59 struct zy7_spi_softc {
60 	device_t		dev;
61 	device_t		child;
62 	struct mtx		sc_mtx;
63 	struct resource		*mem_res;
64 	struct resource		*irq_res;
65 	void			*intrhandle;
66 
67 	uint32_t		cfg_reg_shadow;
68 	uint32_t		spi_clock;
69 	uint32_t		ref_clock;
70 	unsigned int		spi_clk_real_freq;
71 	unsigned int		rx_overflows;
72 	unsigned int		tx_underflows;
73 	unsigned int		interrupts;
74 	unsigned int		stray_ints;
75 	struct spi_command	*cmd;
76 	int			tx_bytes;	/* tx_cmd_sz + tx_data_sz */
77 	int			tx_bytes_sent;
78 	int			rx_bytes;	/* rx_cmd_sz + rx_data_sz */
79 	int			rx_bytes_rcvd;
80 	int			busy;
81 };
82 
83 #define ZY7_SPI_DEFAULT_SPI_CLOCK	50000000
84 
85 #define SPI_SC_LOCK(sc)		mtx_lock(&(sc)->sc_mtx)
86 #define	SPI_SC_UNLOCK(sc)		mtx_unlock(&(sc)->sc_mtx)
87 #define SPI_SC_LOCK_INIT(sc) \
88 	mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->dev),	NULL, MTX_DEF)
89 #define SPI_SC_LOCK_DESTROY(sc)	mtx_destroy(&(sc)->sc_mtx)
90 #define SPI_SC_ASSERT_LOCKED(sc)	mtx_assert(&(sc)->sc_mtx, MA_OWNED)
91 
92 #define RD4(sc, off)		(bus_read_4((sc)->mem_res, (off)))
93 #define WR4(sc, off, val)	(bus_write_4((sc)->mem_res, (off), (val)))
94 
95 /*
96  * SPI device registers.
97  * Reference: Zynq-7000 All Programmable SoC Technical Reference Manual.
98  * (v1.12.1) December 6, 2017.  Xilinx doc UG585.
99  */
100 #define ZY7_SPI_CONFIG_REG		0x0000
101 #define   ZY7_SPI_CONFIG_MODEFAIL_GEN_EN	(1 << 17)
102 #define   ZY7_SPI_CONFIG_MAN_STRT		(1 << 16)
103 #define   ZY7_SPI_CONFIG_MAN_STRT_EN		(1 << 15)
104 #define   ZY7_SPI_CONFIG_MAN_CS			(1 << 14)
105 #define   ZY7_SPI_CONFIG_CS_MASK		(0xf << 10)
106 #define   ZY7_SPI_CONFIG_CS(x)			((0xf ^ (1 << (x))) << 10)
107 #define   ZY7_SPI_CONFIG_PERI_SEL		(1 << 9)
108 #define   ZY7_SPI_CONFIG_REF_CLK		(1 << 8)
109 #define   ZY7_SPI_CONFIG_BAUD_RATE_DIV_MASK	(7 << 3)
110 #define   ZY7_SPI_CONFIG_BAUD_RATE_DIV_SHIFT	3
111 #define   ZY7_SPI_CONFIG_BAUD_RATE_DIV(x)	((x) << 3) /* divide by 2<<x */
112 #define   ZY7_SPI_CONFIG_CLK_PH			(1 << 2)   /* clock phase */
113 #define   ZY7_SPI_CONFIG_CLK_POL		(1 << 1)   /* clock polatiry */
114 #define   ZY7_SPI_CONFIG_MODE_SEL		(1 << 0)   /* master enable */
115 
116 #define ZY7_SPI_INTR_STAT_REG		0x0004
117 #define ZY7_SPI_INTR_EN_REG		0x0008
118 #define ZY7_SPI_INTR_DIS_REG		0x000c
119 #define ZY7_SPI_INTR_MASK_REG		0x0010
120 #define   ZY7_SPI_INTR_TX_FIFO_UNDERFLOW	(1 << 6)
121 #define   ZY7_SPI_INTR_RX_FIFO_FULL		(1 << 5)
122 #define   ZY7_SPI_INTR_RX_FIFO_NOT_EMPTY	(1 << 4)
123 #define   ZY7_SPI_INTR_TX_FIFO_FULL		(1 << 3)
124 #define   ZY7_SPI_INTR_TX_FIFO_NOT_FULL		(1 << 2)
125 #define   ZY7_SPI_INTR_MODE_FAULT		(1 << 1)
126 #define   ZY7_SPI_INTR_RX_OVERFLOW		(1 << 0)
127 
128 #define ZY7_SPI_EN_REG			0x0014
129 #define   ZY7_SPI_ENABLE		(1 << 0)
130 
131 #define ZY7_SPI_DELAY_CTRL_REG		0x0018
132 #define   ZY7_SPI_DELAY_CTRL_BTWN_MASK		(0xff << 16)
133 #define   ZY7_SPI_DELAY_CTRL_BTWN_SHIFT		16
134 #define   ZY7_SPI_DELAY_CTRL_AFTER_MASK		(0xff << 8)
135 #define   ZY7_SPI_DELAY_CTRL_AFTER_SHIFT	8
136 #define   ZY7_SPI_DELAY_CTRL_INIT_MASK		(0xff << 0)
137 #define   ZY7_SPI_DELAY_CTRL_INIT_SHIFT		0
138 
139 #define ZY7_SPI_TX_DATA_REG		0x001c
140 #define ZY7_SPI_RX_DATA_REG		0x0020
141 
142 #define ZY7_SPI_SLV_IDLE_COUNT_REG	0x0024
143 
144 #define ZY7_SPI_TX_THRESH_REG		0x0028
145 #define ZY7_SPI_RX_THRESH_REG		0x002c
146 
147 /* Fill hardware fifo with command and data bytes. */
148 static void
149 zy7_spi_write_fifo(struct zy7_spi_softc *sc, int nbytes)
150 {
151 	uint8_t byte;
152 
153 	while (nbytes > 0) {
154 		if (sc->tx_bytes_sent < sc->cmd->tx_cmd_sz)
155 			/* Writing command. */
156 			byte = *((uint8_t *)sc->cmd->tx_cmd +
157 				 sc->tx_bytes_sent);
158 		else
159 			/* Writing data. */
160 			byte = *((uint8_t *)sc->cmd->tx_data +
161 				 (sc->tx_bytes_sent - sc->cmd->tx_cmd_sz));
162 
163 		WR4(sc, ZY7_SPI_TX_DATA_REG, (uint32_t)byte);
164 
165 		sc->tx_bytes_sent++;
166 		nbytes--;
167 	}
168 }
169 
170 /* Read hardware fifo data into command response and data buffers. */
171 static void
172 zy7_spi_read_fifo(struct zy7_spi_softc *sc)
173 {
174 	uint8_t byte;
175 
176 	do {
177 		byte = RD4(sc, ZY7_SPI_RX_DATA_REG) & 0xff;
178 
179 		if (sc->rx_bytes_rcvd < sc->cmd->rx_cmd_sz)
180 			/* Reading command. */
181 			*((uint8_t *)sc->cmd->rx_cmd + sc->rx_bytes_rcvd) =
182 			    byte;
183 		else
184 			/* Reading data. */
185 			*((uint8_t *)sc->cmd->rx_data +
186 			    (sc->rx_bytes_rcvd - sc->cmd->rx_cmd_sz)) =
187 			    byte;
188 
189 		sc->rx_bytes_rcvd++;
190 
191 	} while (sc->rx_bytes_rcvd < sc->rx_bytes &&
192 	    (RD4(sc, ZY7_SPI_INTR_STAT_REG) &
193 		ZY7_SPI_INTR_RX_FIFO_NOT_EMPTY) != 0);
194 }
195 
196 /* End a transfer early by draining rx fifo and disabling interrupts. */
197 static void
198 zy7_spi_abort_transfer(struct zy7_spi_softc *sc)
199 {
200 	/* Drain receive fifo. */
201 	while ((RD4(sc, ZY7_SPI_INTR_STAT_REG) &
202 		ZY7_SPI_INTR_RX_FIFO_NOT_EMPTY) != 0)
203 		(void)RD4(sc, ZY7_SPI_RX_DATA_REG);
204 
205 	/* Shut down interrupts. */
206 	WR4(sc, ZY7_SPI_INTR_DIS_REG,
207 	    ZY7_SPI_INTR_RX_OVERFLOW |
208 	    ZY7_SPI_INTR_RX_FIFO_NOT_EMPTY |
209 	    ZY7_SPI_INTR_TX_FIFO_NOT_FULL);
210 }
211 
212 static void
213 zy7_spi_intr(void *arg)
214 {
215 	struct zy7_spi_softc *sc = (struct zy7_spi_softc *)arg;
216 	uint32_t istatus;
217 
218 	SPI_SC_LOCK(sc);
219 
220 	sc->interrupts++;
221 
222 	istatus = RD4(sc, ZY7_SPI_INTR_STAT_REG);
223 
224 	/* Stray interrupts can happen if a transfer gets interrupted. */
225 	if (!sc->busy) {
226 		sc->stray_ints++;
227 		SPI_SC_UNLOCK(sc);
228 		return;
229 	}
230 
231 	if ((istatus & ZY7_SPI_INTR_RX_OVERFLOW) != 0) {
232 		device_printf(sc->dev, "rx fifo overflow!\n");
233 		sc->rx_overflows++;
234 
235 		/* Clear status bit. */
236 		WR4(sc, ZY7_SPI_INTR_STAT_REG,
237 		    ZY7_SPI_INTR_RX_OVERFLOW);
238 	}
239 
240 	/* Empty receive fifo before any more transmit data is sent. */
241 	if (sc->rx_bytes_rcvd < sc->rx_bytes &&
242 	    (istatus & ZY7_SPI_INTR_RX_FIFO_NOT_EMPTY) != 0) {
243 		zy7_spi_read_fifo(sc);
244 		if (sc->rx_bytes_rcvd == sc->rx_bytes)
245 			/* Disable receive interrupts. */
246 			WR4(sc, ZY7_SPI_INTR_DIS_REG,
247 			    ZY7_SPI_INTR_RX_FIFO_NOT_EMPTY |
248 			    ZY7_SPI_INTR_RX_OVERFLOW);
249 	}
250 
251 	/* Count tx underflows.  They probably shouldn't happen. */
252 	if ((istatus & ZY7_SPI_INTR_TX_FIFO_UNDERFLOW) != 0) {
253 		sc->tx_underflows++;
254 
255 		/* Clear status bit. */
256 		WR4(sc, ZY7_SPI_INTR_STAT_REG,
257 		    ZY7_SPI_INTR_TX_FIFO_UNDERFLOW);
258 	}
259 
260 	/* Fill transmit fifo. */
261 	if (sc->tx_bytes_sent < sc->tx_bytes &&
262 	    (istatus & ZY7_SPI_INTR_TX_FIFO_NOT_FULL) != 0) {
263 		zy7_spi_write_fifo(sc, MIN(96, sc->tx_bytes -
264 			sc->tx_bytes_sent));
265 
266 		if (sc->tx_bytes_sent == sc->tx_bytes) {
267 			/* Disable transmit FIFO interrupt, enable receive
268 			 * FIFO interrupt.
269 			 */
270 			WR4(sc, ZY7_SPI_INTR_DIS_REG,
271 			    ZY7_SPI_INTR_TX_FIFO_NOT_FULL);
272 			WR4(sc, ZY7_SPI_INTR_EN_REG,
273 			    ZY7_SPI_INTR_RX_FIFO_NOT_EMPTY);
274 		}
275 	}
276 
277 	/* Finished with transfer? */
278 	if (sc->tx_bytes_sent == sc->tx_bytes &&
279 	    sc->rx_bytes_rcvd == sc->rx_bytes) {
280 		/* De-assert CS. */
281 		sc->cfg_reg_shadow &=
282 		    ~(ZY7_SPI_CONFIG_CLK_PH | ZY7_SPI_CONFIG_CLK_POL);
283 		sc->cfg_reg_shadow |= ZY7_SPI_CONFIG_CS_MASK;
284 		WR4(sc, ZY7_SPI_CONFIG_REG, sc->cfg_reg_shadow);
285 
286 		wakeup(sc->dev);
287 	}
288 
289 	SPI_SC_UNLOCK(sc);
290 }
291 
292 /* Initialize hardware. */
293 static int
294 zy7_spi_init_hw(struct zy7_spi_softc *sc)
295 {
296 	uint32_t baud_div;
297 
298 	/* Find best clock divider. Divide by 2 not supported. */
299 	baud_div = 1;
300 	while ((sc->ref_clock >> (baud_div + 1)) > sc->spi_clock &&
301 	    baud_div < 8)
302 		baud_div++;
303 	if (baud_div >= 8) {
304 		device_printf(sc->dev, "cannot configure clock divider: ref=%d"
305 		    " spi=%d.\n", sc->ref_clock, sc->spi_clock);
306 		return (EINVAL);
307 	}
308 	sc->spi_clk_real_freq = sc->ref_clock >> (baud_div + 1);
309 
310 	/* Set up configuration register. */
311 	sc->cfg_reg_shadow =
312 	    ZY7_SPI_CONFIG_MAN_CS |
313 	    ZY7_SPI_CONFIG_CS_MASK |
314 	    ZY7_SPI_CONFIG_BAUD_RATE_DIV(baud_div) |
315 	    ZY7_SPI_CONFIG_MODE_SEL;
316 	WR4(sc, ZY7_SPI_CONFIG_REG, sc->cfg_reg_shadow);
317 
318 	/* Set thresholds. */
319 	WR4(sc, ZY7_SPI_TX_THRESH_REG, 32);
320 	WR4(sc, ZY7_SPI_RX_THRESH_REG, 1);
321 
322 	/* Clear and disable all interrupts. */
323 	WR4(sc, ZY7_SPI_INTR_STAT_REG, ~0);
324 	WR4(sc, ZY7_SPI_INTR_DIS_REG, ~0);
325 
326 	/* Enable SPI. */
327 	WR4(sc, ZY7_SPI_EN_REG, ZY7_SPI_ENABLE);
328 
329 	return (0);
330 }
331 
332 static void
333 zy7_spi_add_sysctls(device_t dev)
334 {
335 	struct zy7_spi_softc *sc = device_get_softc(dev);
336 	struct sysctl_ctx_list *ctx;
337 	struct sysctl_oid_list *child;
338 
339 	ctx = device_get_sysctl_ctx(dev);
340 	child = SYSCTL_CHILDREN(device_get_sysctl_tree(dev));
341 
342 	SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "spi_clk_real_freq", CTLFLAG_RD,
343 	    &sc->spi_clk_real_freq, 0, "SPI clock real frequency");
344 
345 	SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "rx_overflows", CTLFLAG_RD,
346 	    &sc->rx_overflows, 0, "RX FIFO overflow events");
347 
348 	SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "tx_underflows", CTLFLAG_RD,
349 	    &sc->tx_underflows, 0, "TX FIFO underflow events");
350 
351 	SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "interrupts", CTLFLAG_RD,
352 	    &sc->interrupts, 0, "interrupt calls");
353 
354 	SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "stray_ints", CTLFLAG_RD,
355 	    &sc->stray_ints, 0, "stray interrupts");
356 }
357 
358 static int
359 zy7_spi_probe(device_t dev)
360 {
361 
362 	if (!ofw_bus_status_okay(dev))
363 		return (ENXIO);
364 
365 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
366 		return (ENXIO);
367 
368 	device_set_desc(dev, "Zynq SPI Controller");
369 
370 	return (BUS_PROBE_DEFAULT);
371 }
372 
373 static int zy7_spi_detach(device_t);
374 
375 static int
376 zy7_spi_attach(device_t dev)
377 {
378 	struct zy7_spi_softc *sc;
379 	int rid, err;
380 	phandle_t node;
381 	pcell_t cell;
382 
383 	sc = device_get_softc(dev);
384 	sc->dev = dev;
385 
386 	SPI_SC_LOCK_INIT(sc);
387 
388 	/* Get ref-clock and spi-clock properties. */
389 	node = ofw_bus_get_node(dev);
390 	if (OF_getprop(node, "ref-clock", &cell, sizeof(cell)) > 0)
391 		sc->ref_clock = fdt32_to_cpu(cell);
392 	else {
393 		device_printf(dev, "must have ref-clock property\n");
394 		return (ENXIO);
395 	}
396 	if (OF_getprop(node, "spi-clock", &cell, sizeof(cell)) > 0)
397 		sc->spi_clock = fdt32_to_cpu(cell);
398 	else
399 		sc->spi_clock = ZY7_SPI_DEFAULT_SPI_CLOCK;
400 
401 	/* Get memory resource. */
402 	rid = 0;
403 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
404 	    RF_ACTIVE);
405 	if (sc->mem_res == NULL) {
406 		device_printf(dev, "could not allocate memory resources.\n");
407 		zy7_spi_detach(dev);
408 		return (ENOMEM);
409 	}
410 
411 	/* Allocate IRQ. */
412 	rid = 0;
413 	sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
414 	    RF_ACTIVE);
415 	if (sc->irq_res == NULL) {
416 		device_printf(dev, "could not allocate IRQ resource.\n");
417 		zy7_spi_detach(dev);
418 		return (ENOMEM);
419 	}
420 
421 	/* Activate the interrupt. */
422 	err = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
423 	    NULL, zy7_spi_intr, sc, &sc->intrhandle);
424 	if (err) {
425 		device_printf(dev, "could not setup IRQ.\n");
426 		zy7_spi_detach(dev);
427 		return (err);
428 	}
429 
430 	/* Configure the device. */
431 	err = zy7_spi_init_hw(sc);
432 	if (err) {
433 		zy7_spi_detach(dev);
434 		return (err);
435 	}
436 
437 	sc->child = device_add_child(dev, "spibus", -1);
438 
439 	zy7_spi_add_sysctls(dev);
440 
441 	/* Attach spibus driver as a child later when interrupts work. */
442 	config_intrhook_oneshot((ich_func_t)bus_generic_attach, dev);
443 
444 	return (0);
445 }
446 
447 static int
448 zy7_spi_detach(device_t dev)
449 {
450 	struct zy7_spi_softc *sc = device_get_softc(dev);
451 
452 	if (device_is_attached(dev))
453 		bus_generic_detach(dev);
454 
455 	/* Delete child bus. */
456 	if (sc->child)
457 		device_delete_child(dev, sc->child);
458 
459 	/* Disable hardware. */
460 	if (sc->mem_res != NULL) {
461 		/* Disable SPI. */
462 		WR4(sc, ZY7_SPI_EN_REG, 0);
463 
464 		/* Clear and disable all interrupts. */
465 		WR4(sc, ZY7_SPI_INTR_STAT_REG, ~0);
466 		WR4(sc, ZY7_SPI_INTR_DIS_REG, ~0);
467 	}
468 
469 	/* Teardown and release interrupt. */
470 	if (sc->irq_res != NULL) {
471 		if (sc->intrhandle)
472 			bus_teardown_intr(dev, sc->irq_res, sc->intrhandle);
473 		bus_release_resource(dev, SYS_RES_IRQ,
474 		    rman_get_rid(sc->irq_res), sc->irq_res);
475 	}
476 
477 	/* Release memory resource. */
478 	if (sc->mem_res != NULL)
479 		bus_release_resource(dev, SYS_RES_MEMORY,
480 		    rman_get_rid(sc->mem_res), sc->mem_res);
481 
482 	SPI_SC_LOCK_DESTROY(sc);
483 
484 	return (0);
485 }
486 
487 static phandle_t
488 zy7_spi_get_node(device_t bus, device_t dev)
489 {
490 
491 	return (ofw_bus_get_node(bus));
492 }
493 
494 static int
495 zy7_spi_transfer(device_t dev, device_t child, struct spi_command *cmd)
496 {
497 	struct zy7_spi_softc *sc = device_get_softc(dev);
498 	uint32_t cs;
499 	uint32_t mode;
500 	int err = 0;
501 
502 	KASSERT(cmd->tx_cmd_sz == cmd->rx_cmd_sz,
503 	    ("TX/RX command sizes should be equal"));
504 	KASSERT(cmd->tx_data_sz == cmd->rx_data_sz,
505 	    ("TX/RX data sizes should be equal"));
506 
507 	/* Get chip select and mode for this child. */
508 	spibus_get_cs(child, &cs);
509 	cs &= ~SPIBUS_CS_HIGH;
510 	if (cs > 2) {
511 		device_printf(dev, "Invalid chip select %d requested by %s",
512 		    cs, device_get_nameunit(child));
513 		return (EINVAL);
514 	}
515 	spibus_get_mode(child, &mode);
516 
517 	SPI_SC_LOCK(sc);
518 
519 	/* Wait for controller available. */
520 	while (sc->busy != 0) {
521 		err = mtx_sleep(dev, &sc->sc_mtx, 0, "zspi0", 0);
522 		if (err) {
523 			SPI_SC_UNLOCK(sc);
524 			return (err);
525 		}
526 	}
527 
528 	/* Start transfer. */
529 	sc->busy = 1;
530 	sc->cmd = cmd;
531 	sc->tx_bytes = sc->cmd->tx_cmd_sz + sc->cmd->tx_data_sz;
532 	sc->tx_bytes_sent = 0;
533 	sc->rx_bytes = sc->cmd->rx_cmd_sz + sc->cmd->rx_data_sz;
534 	sc->rx_bytes_rcvd = 0;
535 
536 	/* Enable interrupts.  zy7_spi_intr() will handle transfer. */
537 	WR4(sc, ZY7_SPI_INTR_EN_REG,
538 	    ZY7_SPI_INTR_TX_FIFO_NOT_FULL |
539 	    ZY7_SPI_INTR_RX_OVERFLOW);
540 
541 	/* Handle polarity and phase. */
542 	if (mode == SPIBUS_MODE_CPHA || mode == SPIBUS_MODE_CPOL_CPHA)
543 		sc->cfg_reg_shadow |= ZY7_SPI_CONFIG_CLK_PH;
544 	if (mode == SPIBUS_MODE_CPOL || mode == SPIBUS_MODE_CPOL_CPHA)
545 		sc->cfg_reg_shadow |= ZY7_SPI_CONFIG_CLK_POL;
546 
547 	/* Assert CS. */
548 	sc->cfg_reg_shadow &= ~ZY7_SPI_CONFIG_CS_MASK;
549 	sc->cfg_reg_shadow |= ZY7_SPI_CONFIG_CS(cs);
550 	WR4(sc, ZY7_SPI_CONFIG_REG, sc->cfg_reg_shadow);
551 
552 	/* Wait for completion. */
553 	err = mtx_sleep(dev, &sc->sc_mtx, 0, "zspi1", hz * 2);
554 	if (err)
555 		zy7_spi_abort_transfer(sc);
556 
557 	/* Release controller. */
558 	sc->busy = 0;
559 	wakeup_one(dev);
560 
561 	SPI_SC_UNLOCK(sc);
562 
563 	return (err);
564 }
565 
566 static device_method_t zy7_spi_methods[] = {
567 	/* Device interface */
568 	DEVMETHOD(device_probe,		zy7_spi_probe),
569 	DEVMETHOD(device_attach,	zy7_spi_attach),
570 	DEVMETHOD(device_detach,	zy7_spi_detach),
571 
572 	/* SPI interface */
573 	DEVMETHOD(spibus_transfer,	zy7_spi_transfer),
574 
575 	/* ofw_bus interface */
576 	DEVMETHOD(ofw_bus_get_node,	zy7_spi_get_node),
577 
578 	DEVMETHOD_END
579 };
580 
581 static driver_t zy7_spi_driver = {
582 	"zy7_spi",
583 	zy7_spi_methods,
584 	sizeof(struct zy7_spi_softc),
585 };
586 
587 DRIVER_MODULE(zy7_spi, simplebus, zy7_spi_driver, 0, 0);
588 DRIVER_MODULE(ofw_spibus, zy7_spi, ofw_spibus_driver, 0, 0);
589 SIMPLEBUS_PNP_INFO(compat_data);
590 MODULE_DEPEND(zy7_spi, ofw_spibus, 1, 1, 1);
591