xref: /netbsd-src/sys/dev/ic/w83l518d_sdmmc.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* $NetBSD: w83l518d_sdmmc.c,v 1.3 2010/10/07 12:06:09 kiyohara Exp $ */
2 
3 /*
4  * Copyright (c) 2009 Jared D. McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
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. The name of the author may not be used to endorse or promote products
13  *    derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: w83l518d_sdmmc.c,v 1.3 2010/10/07 12:06:09 kiyohara Exp $");
30 
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/systm.h>
34 #include <sys/errno.h>
35 #include <sys/ioctl.h>
36 #include <sys/syslog.h>
37 #include <sys/device.h>
38 #include <sys/proc.h>
39 
40 #include <sys/bus.h>
41 
42 #include <dev/sdmmc/sdmmcvar.h>
43 #include <dev/sdmmc/sdmmcchip.h>
44 #include <dev/sdmmc/sdmmc_ioreg.h>
45 
46 #include <dev/isa/isavar.h>
47 #include <dev/isa/isadmavar.h>
48 
49 #include <dev/ic/w83l518dreg.h>
50 #include <dev/ic/w83l518dvar.h>
51 #include <dev/ic/w83l518d_sdmmc.h>
52 
53 /* #define WB_SDMMC_DEBUG */
54 
55 #ifdef WB_SDMMC_DEBUG
56 static int wb_sdmmc_debug = 1;
57 #else
58 static int wb_sdmmc_debug = 0;
59 #endif
60 
61 #if defined(__NetBSD__) && __NetBSD_Version__ < 599000600
62 #define	snprintb(b, l, f, v) bitmask_snprintf((v), (f), (b), (l))
63 #endif
64 
65 #define REPORT(_wb, ...)					\
66 	if (wb_sdmmc_debug > 0)					\
67 		aprint_normal_dev(((struct wb_softc *)(_wb))->wb_dev, \
68 				  __VA_ARGS__)
69 
70 static int	wb_sdmmc_host_reset(sdmmc_chipset_handle_t);
71 static uint32_t	wb_sdmmc_host_ocr(sdmmc_chipset_handle_t);
72 static int	wb_sdmmc_host_maxblklen(sdmmc_chipset_handle_t);
73 static int	wb_sdmmc_card_detect(sdmmc_chipset_handle_t);
74 static int	wb_sdmmc_write_protect(sdmmc_chipset_handle_t);
75 static int	wb_sdmmc_bus_power(sdmmc_chipset_handle_t, uint32_t);
76 static int	wb_sdmmc_bus_clock(sdmmc_chipset_handle_t, int);
77 static int	wb_sdmmc_bus_width(sdmmc_chipset_handle_t, int);
78 static int	wb_sdmmc_bus_rod(sdmmc_chipset_handle_t, int);
79 static void	wb_sdmmc_exec_command(sdmmc_chipset_handle_t,
80 				      struct sdmmc_command *);
81 static void	wb_sdmmc_card_enable_intr(sdmmc_chipset_handle_t, int);
82 static void	wb_sdmmc_card_intr_ack(sdmmc_chipset_handle_t);
83 
84 static struct sdmmc_chip_functions wb_sdmmc_chip_functions = {
85 	.host_reset = wb_sdmmc_host_reset,
86 	.host_ocr = wb_sdmmc_host_ocr,
87 	.host_maxblklen = wb_sdmmc_host_maxblklen,
88 	.card_detect = wb_sdmmc_card_detect,
89 	.write_protect = wb_sdmmc_write_protect,
90 	.bus_power = wb_sdmmc_bus_power,
91 	.bus_clock = wb_sdmmc_bus_clock,
92 	.bus_width = wb_sdmmc_bus_width,
93 	.bus_rod = wb_sdmmc_bus_rod,
94 	.exec_command = wb_sdmmc_exec_command,
95 	.card_enable_intr = wb_sdmmc_card_enable_intr,
96 	.card_intr_ack = wb_sdmmc_card_intr_ack,
97 };
98 
99 static void
100 wb_sdmmc_read_data(struct wb_softc *wb, uint8_t *data, int len)
101 {
102 	bus_space_read_multi_1(wb->wb_iot, wb->wb_ioh, WB_SD_FIFO, data, len);
103 }
104 
105 static void
106 wb_sdmmc_write_data(struct wb_softc *wb, uint8_t *data, int len)
107 {
108 	bus_space_write_multi_1(wb->wb_iot, wb->wb_ioh, WB_SD_FIFO, data, len);
109 }
110 
111 static void
112 wb_sdmmc_discover(void *opaque)
113 {
114 	struct wb_softc *wb = opaque;
115 
116 	REPORT(wb, "TRACE: discover(wb)\n");
117 
118 	sdmmc_needs_discover(wb->wb_sdmmc_dev);
119 }
120 
121 static bool
122 wb_sdmmc_enable(struct wb_softc *wb)
123 {
124 	int i = 5000;
125 
126 	REPORT(wb, "TRACE: enable(wb)\n");
127 
128 	/* put the device in a known state */
129 	wb_idx_write(wb, WB_INDEX_SETUP, WB_SETUP_SOFT_RST);
130 	while (--i > 0 && wb_idx_read(wb, WB_INDEX_SETUP) & WB_SETUP_SOFT_RST)
131 		delay(100);
132 	if (i == 0) {
133 		aprint_error_dev(wb->wb_dev, "timeout resetting device\n");
134 		return false;
135 	}
136 	wb_idx_write(wb, WB_INDEX_CLK, wb->wb_sdmmc_clk);
137 	wb_idx_write(wb, WB_INDEX_FIFOEN, 0);
138 	wb_idx_write(wb, WB_INDEX_DMA, 0);
139 	wb_idx_write(wb, WB_INDEX_PBSMSB, 0);
140 	wb_idx_write(wb, WB_INDEX_PBSLSB, 0);
141 	/* drain FIFO */
142 	while ((wb_read(wb, WB_SD_FIFOSTS) & WB_FIFO_EMPTY) == 0)
143 		wb_read(wb, WB_SD_FIFO);
144 
145 	wb_write(wb, WB_SD_CSR, 0);
146 
147 	wb_write(wb, WB_SD_INTCTL, WB_INT_DEFAULT);
148 
149 	wb_sdmmc_card_detect(wb);
150 
151 	return true;
152 }
153 
154 static bool
155 wb_sdmmc_disable(struct wb_softc *wb)
156 {
157 	uint8_t val;
158 
159 	REPORT(wb, "TRACE: disable(wb)\n");
160 
161 	val = wb_read(wb, WB_SD_CSR);
162 	val |= WB_CSR_POWER_N;
163 	wb_write(wb, WB_SD_CSR, val);
164 
165 	return true;
166 }
167 
168 void
169 wb_sdmmc_attach(struct wb_softc *wb)
170 {
171 	struct sdmmcbus_attach_args saa;
172 
173 	callout_init(&wb->wb_sdmmc_callout, 0);
174 	callout_setfunc(&wb->wb_sdmmc_callout, wb_sdmmc_discover, wb);
175 
176 	wb->wb_sdmmc_width = 1;
177 	wb->wb_sdmmc_clk = WB_CLK_375K;
178 
179 	if (wb_sdmmc_enable(wb) == false)
180 		return;
181 
182 	memset(&saa, 0, sizeof(saa));
183 	saa.saa_busname = "sdmmc";
184 	saa.saa_sct = &wb_sdmmc_chip_functions;
185 	saa.saa_sch = wb;
186 	saa.saa_clkmin = 375;
187 	saa.saa_clkmax = 24000;
188 	saa.saa_caps = SMC_CAPS_4BIT_MODE;
189 
190 	wb->wb_sdmmc_dev = config_found(wb->wb_dev, &saa, NULL);
191 }
192 
193 int
194 wb_sdmmc_detach(struct wb_softc *wb, int flags)
195 {
196 	int rv;
197 
198 	if (wb->wb_sdmmc_dev) {
199 		rv = config_detach(wb->wb_sdmmc_dev, flags);
200 		if (rv)
201 			return rv;
202 	}
203 	wb_sdmmc_disable(wb);
204 
205 	callout_halt(&wb->wb_sdmmc_callout, NULL);
206 	callout_destroy(&wb->wb_sdmmc_callout);
207 
208 	return 0;
209 }
210 
211 /*
212  * SD/MMC interface
213  */
214 static int
215 wb_sdmmc_host_reset(sdmmc_chipset_handle_t sch)
216 {
217 	REPORT(sch, "TRACE: sdmmc/host_reset(wb)\n");
218 
219 	return 0;
220 }
221 
222 static uint32_t
223 wb_sdmmc_host_ocr(sdmmc_chipset_handle_t sch)
224 {
225 	REPORT(sch, "TRACE: sdmmc/host_ocr(wb)\n");
226 
227 	return MMC_OCR_3_2V_3_3V | MMC_OCR_3_3V_3_4V;
228 }
229 
230 static int
231 wb_sdmmc_host_maxblklen(sdmmc_chipset_handle_t sch)
232 {
233 	REPORT(sch, "TRACE: sdmmc/host_maxblklen(wb)\n");
234 
235 	return 512;	/* XXX */
236 }
237 
238 static int
239 wb_sdmmc_card_detect(sdmmc_chipset_handle_t sch)
240 {
241 	struct wb_softc *wb = sch;
242 	int rv;
243 
244 	wb_led(wb, true);
245 	rv = (wb_read(wb, WB_SD_CSR) & WB_CSR_CARD_PRESENT) ? 1 : 0;
246 	wb_led(wb, false);
247 
248 	REPORT(wb, "TRACE: sdmmc/card_detect(wb) -> %d\n", rv);
249 
250 	return rv;
251 }
252 
253 static int
254 wb_sdmmc_write_protect(sdmmc_chipset_handle_t sch)
255 {
256 	struct wb_softc *wb = sch;
257 	int rv;
258 
259 	wb_led(wb, true);
260 	rv = (wb_read(wb, WB_SD_CSR) & WB_CSR_WRITE_PROTECT) ? 1 : 0;
261 	wb_led(wb, false);
262 
263 	REPORT(wb, "TRACE: sdmmc/write_protect(wb) -> %d\n", rv);
264 
265 	return rv;
266 }
267 
268 static int
269 wb_sdmmc_bus_power(sdmmc_chipset_handle_t sch, uint32_t ocr)
270 {
271 	REPORT(sch, "TRACE: sdmmc/bus_power(wb, ocr=%d)\n", ocr);
272 
273 	return 0;
274 }
275 
276 static int
277 wb_sdmmc_bus_clock(sdmmc_chipset_handle_t sch, int freq)
278 {
279 	struct wb_softc *wb = sch;
280 	uint8_t clk;
281 
282 	REPORT(wb, "TRACE: sdmmc/bus_clock(wb, freq=%d)\n", freq);
283 
284 	if (freq >= 24000)
285 		clk = WB_CLK_24M;
286 	else if (freq >= 16000)
287 		clk = WB_CLK_16M;
288 	else if (freq >= 12000)
289 		clk = WB_CLK_12M;
290 	else
291 		clk = WB_CLK_375K;
292 
293 	wb->wb_sdmmc_clk = clk;
294 
295 	if (wb_idx_read(wb, WB_INDEX_CLK) != clk)
296 		wb_idx_write(wb, WB_INDEX_CLK, clk);
297 
298 	return 0;
299 }
300 
301 static int
302 wb_sdmmc_bus_width(sdmmc_chipset_handle_t sch, int width)
303 {
304 	struct wb_softc *wb = sch;
305 
306 	REPORT(wb, "TRACE: sdmmc/bus_width(wb, width=%d)\n", width);
307 
308 	if (width != 1 && width != 4)
309 		return 1;
310 
311 	wb->wb_sdmmc_width = width;
312 
313 	return 0;
314 }
315 
316 static int
317 wb_sdmmc_bus_rod(sdmmc_chipset_handle_t sch, int on)
318 {
319 
320 	/* Not support */
321 	return -1;
322 }
323 
324 
325 static void
326 wb_sdmmc_rsp_read_long(struct wb_softc *wb, struct sdmmc_command *cmd)
327 {
328 	uint8_t *p = (uint8_t *)cmd->c_resp;
329 	int i;
330 
331 	if (wb_idx_read(wb, WB_INDEX_RESPLEN) != 1) {
332 		cmd->c_error = ENXIO;
333 		return;
334 	}
335 
336 	for (i = 12; i >= 0; i -= 4) {
337 		p[3] = wb_idx_read(wb, WB_INDEX_RESP(i + 0));
338 		p[2] = wb_idx_read(wb, WB_INDEX_RESP(i + 1));
339 		p[1] = wb_idx_read(wb, WB_INDEX_RESP(i + 2));
340 		p[0] = wb_idx_read(wb, WB_INDEX_RESP(i + 3));
341 		p += 4;
342 	}
343 }
344 
345 static void
346 wb_sdmmc_rsp_read_short(struct wb_softc *wb, struct sdmmc_command *cmd)
347 {
348 	uint8_t *p = (uint8_t *)cmd->c_resp;
349 
350 	if (wb_idx_read(wb, WB_INDEX_RESPLEN) != 0) {
351 		cmd->c_error = ENXIO;
352 		return;
353 	}
354 
355 	p[3] = wb_idx_read(wb, WB_INDEX_RESP(12));
356 	p[2] = wb_idx_read(wb, WB_INDEX_RESP(13));
357 	p[1] = wb_idx_read(wb, WB_INDEX_RESP(14));
358 	p[0] = wb_idx_read(wb, WB_INDEX_RESP(15));
359 }
360 
361 static int
362 wb_sdmmc_transfer_data(struct wb_softc *wb, struct sdmmc_command *cmd)
363 {
364 	uint8_t fifosts;
365 	int datalen, retry = 5000;
366 
367 	if (wb->wb_sdmmc_intsts & WB_INT_CARD)
368 		return EIO;
369 
370 	fifosts = wb_read(wb, WB_SD_FIFOSTS);
371 	if (ISSET(cmd->c_flags, SCF_CMD_READ)) {
372 		if (fifosts & WB_FIFO_EMPTY) {
373 			while (--retry > 0) {
374 				fifosts = wb_read(wb, WB_SD_FIFOSTS);
375 				if ((fifosts & WB_FIFO_EMPTY) == 0)
376 					break;
377 				delay(100);
378 			}
379 			if (retry == 0)
380 				return EBUSY;
381 		}
382 
383 		if (fifosts & WB_FIFO_FULL)
384 			datalen = 16;
385 		else
386 			datalen = fifosts & WB_FIFO_DEPTH_MASK;
387 	} else {
388 		if (fifosts & WB_FIFO_FULL) {
389 			while (--retry > 0) {
390 				fifosts = wb_read(wb, WB_SD_FIFOSTS);
391 				if ((fifosts & WB_FIFO_FULL) == 0)
392 					break;
393 				delay(100);
394 			}
395 			if (retry == 0)
396 				return EBUSY;
397 		}
398 
399 		if (fifosts & WB_FIFO_EMPTY)
400 			datalen = 16;
401 		else
402 			datalen = 16 - (fifosts & WB_FIFO_DEPTH_MASK);
403 	}
404 
405 	datalen = MIN(datalen, cmd->c_resid);
406 	if (datalen > 0) {
407 		if (ISSET(cmd->c_flags, SCF_CMD_READ))
408 			wb_sdmmc_read_data(wb, cmd->c_buf, datalen);
409 		else
410 			wb_sdmmc_write_data(wb, cmd->c_buf, datalen);
411 
412 		cmd->c_buf += datalen;
413 		cmd->c_resid -= datalen;
414 	}
415 
416 	return 0;
417 }
418 
419 static void
420 wb_sdmmc_exec_command(sdmmc_chipset_handle_t sch, struct sdmmc_command *cmd)
421 {
422 	static const int opcodes[] = {
423 		11, 17, 18, 20, 24, 25, 26, 27, 30, 42, 51, 56
424 	};
425 	struct wb_softc *wb = sch;
426 	uint8_t val;
427 	int blklen;
428 	int error;
429 	int i, retry;
430 	int s;
431 
432 	REPORT(wb, "TRACE: sdmmc/exec_command(wb, cmd) "
433 	    "opcode %d flags 0x%x data %p datalen %d\n",
434 	    cmd->c_opcode, cmd->c_flags, cmd->c_data, cmd->c_datalen);
435 
436 	if (cmd->c_datalen > 0) {
437 		/* controller only supports a select number of data opcodes */
438 		for (i = 0; i < __arraycount(opcodes); i++)
439 			if (opcodes[i] == cmd->c_opcode)
440 				break;
441 		if (i == __arraycount(opcodes)) {
442 			cmd->c_error = EINVAL;
443 			goto done;
444 		}
445 
446 		/* Fragment the data into proper blocks */
447 		blklen = MIN(cmd->c_datalen, cmd->c_blklen);
448 
449 		if (cmd->c_datalen % blklen > 0) {
450 			aprint_error_dev(wb->wb_dev,
451 			    "data is not a multiple of %u bytes\n", blklen);
452 			cmd->c_error = EINVAL;
453 			goto done;
454 		}
455 
456 		/* setup block size registers */
457 		blklen = blklen + 2 * wb->wb_sdmmc_width;
458 		wb_idx_write(wb, WB_INDEX_PBSMSB,
459 		    ((blklen >> 4) & 0xf0) | (wb->wb_sdmmc_width / 4));
460 		wb_idx_write(wb, WB_INDEX_PBSLSB, blklen & 0xff);
461 
462 		/* clear FIFO */
463 		val = wb_idx_read(wb, WB_INDEX_SETUP);
464 		val |= WB_SETUP_FIFO_RST;
465 		wb_idx_write(wb, WB_INDEX_SETUP, val);
466 		while (wb_idx_read(wb, WB_INDEX_SETUP) & WB_SETUP_FIFO_RST)
467 			;
468 
469 		cmd->c_resid = cmd->c_datalen;
470 		cmd->c_buf = cmd->c_data;
471 
472 		/* setup FIFO thresholds */
473 		if (ISSET(cmd->c_flags, SCF_CMD_READ))
474 			wb_idx_write(wb, WB_INDEX_FIFOEN, WB_FIFOEN_FULL | 8);
475 		else {
476 			wb_idx_write(wb, WB_INDEX_FIFOEN, WB_FIFOEN_EMPTY | 8);
477 
478 			/* pre-fill the FIFO on write */
479 			error = wb_sdmmc_transfer_data(wb, cmd);
480 			if (error) {
481 				cmd->c_error = error;
482 				goto done;
483 			}
484 		}
485 	}
486 
487 	s = splsdmmc();
488 	wb->wb_sdmmc_intsts = 0;
489 	wb_write(wb, WB_SD_COMMAND, cmd->c_opcode);
490 	wb_write(wb, WB_SD_COMMAND, (cmd->c_arg >> 24) & 0xff);
491 	wb_write(wb, WB_SD_COMMAND, (cmd->c_arg >> 16) & 0xff);
492 	wb_write(wb, WB_SD_COMMAND, (cmd->c_arg >> 8) & 0xff);
493 	wb_write(wb, WB_SD_COMMAND, (cmd->c_arg >> 0) & 0xff);
494 	splx(s);
495 
496 	retry = 100000;
497 	while (wb_idx_read(wb, WB_INDEX_STATUS) & WB_STATUS_CARD_TRAFFIC) {
498 		if (--retry == 0)
499 			break;
500 		delay(1);
501 	}
502 	if (wb_idx_read(wb, WB_INDEX_STATUS) & WB_STATUS_CARD_TRAFFIC) {
503 		REPORT(wb,
504 		    "command timed out, WB_INDEX_STATUS = 0x%02x\n",
505 		    wb_idx_read(wb, WB_INDEX_STATUS));
506 		cmd->c_error = ETIMEDOUT;
507 		goto done;
508 	}
509 
510 	if (ISSET(cmd->c_flags, SCF_RSP_PRESENT)) {
511 		if (wb->wb_sdmmc_intsts & WB_INT_TIMEOUT) {
512 			cmd->c_error = ETIMEDOUT;
513 			goto done;
514 		}
515 
516 		if (ISSET(cmd->c_flags, SCF_RSP_136))
517 			wb_sdmmc_rsp_read_long(wb, cmd);
518 		else
519 			wb_sdmmc_rsp_read_short(wb, cmd);
520 	}
521 
522 	if (cmd->c_error == 0 && cmd->c_datalen > 0) {
523 		wb_led(wb, true);
524 		while (cmd->c_resid > 0) {
525 			error = wb_sdmmc_transfer_data(wb, cmd);
526 			if (error) {
527 				cmd->c_error = error;
528 				break;
529 			}
530 		}
531 		wb_led(wb, false);
532 	}
533 
534 done:
535 	SET(cmd->c_flags, SCF_ITSDONE);
536 
537 	if (cmd->c_error) {
538 		REPORT(wb,
539 		    "cmd error = %d, op = %d [%s] "
540 		    "blklen %d datalen %d resid %d\n",
541 		    cmd->c_error, cmd->c_opcode,
542 		    ISSET(cmd->c_flags, SCF_CMD_READ) ? "rd" : "wr",
543 		    cmd->c_blklen, cmd->c_datalen, cmd->c_resid);
544 	}
545 }
546 
547 static void
548 wb_sdmmc_card_enable_intr(sdmmc_chipset_handle_t sch, int enable)
549 {
550 	REPORT(sch, "TRACE: sdmmc/card_enable_intr(wb, enable=%d)\n", enable);
551 }
552 
553 static void
554 wb_sdmmc_card_intr_ack(sdmmc_chipset_handle_t sch)
555 {
556 	REPORT(sch, "TRACE: sdmmc/card_intr_ack(wb)\n");
557 }
558 
559 /*
560  * intr handler
561  */
562 int
563 wb_sdmmc_intr(struct wb_softc *wb)
564 {
565 	uint8_t val;
566 
567 	val = wb_read(wb, WB_SD_INTSTS);
568 	if (val == 0xff || val == 0x00)
569 		return 0;
570 
571 	if (wb->wb_sdmmc_dev == NULL)
572 		return 1;
573 
574 	wb->wb_sdmmc_intsts |= val;
575 
576 	if (wb_sdmmc_debug) {
577 		char buf[64];
578 		snprintb(buf, sizeof(buf),
579 		    "\20\1TC\2BUSYEND\3PROGEND\4TIMEOUT"
580 		    "\5CRC\6FIFO\7CARD\010PENDING",
581 		    val);
582 		REPORT(wb, "WB_SD_INTSTS = %s\n", buf);
583 	}
584 
585 	if (val & WB_INT_CARD)
586 		callout_schedule(&wb->wb_sdmmc_callout, hz / 4);
587 
588 	return 1;
589 }
590 
591 /*
592  * pmf
593  */
594 bool
595 wb_sdmmc_suspend(struct wb_softc *wb)
596 {
597 	return wb_sdmmc_disable(wb);
598 }
599 
600 bool
601 wb_sdmmc_resume(struct wb_softc *wb)
602 {
603 	uint8_t val;
604 
605 	val = wb_read(wb, WB_SD_CSR);
606 	val &= ~WB_CSR_POWER_N;
607 	wb_write(wb, WB_SD_CSR, val);
608 
609 	if (wb_sdmmc_enable(wb) == false)
610 		return false;
611 
612 	if (wb_idx_read(wb, WB_INDEX_CLK) != wb->wb_sdmmc_clk)
613 		wb_idx_write(wb, WB_INDEX_CLK, wb->wb_sdmmc_clk);
614 
615 	return true;
616 }
617