xref: /openbmc/u-boot/drivers/mmc/tegra_mmc.c (revision 85231c08)
1 /*
2  * (C) Copyright 2009 SAMSUNG Electronics
3  * Minkyu Kang <mk7.kang@samsung.com>
4  * Jaehoon Chung <jh80.chung@samsung.com>
5  * Portions Copyright 2011-2016 NVIDIA Corporation
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <bouncebuf.h>
11 #include <common.h>
12 #include <dm.h>
13 #include <errno.h>
14 #include <mmc.h>
15 #include <asm/gpio.h>
16 #include <asm/io.h>
17 #include <asm/arch-tegra/tegra_mmc.h>
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 struct tegra_mmc_plat {
22 	struct mmc_config cfg;
23 	struct mmc mmc;
24 };
25 
26 struct tegra_mmc_priv {
27 	struct tegra_mmc *reg;
28 	struct reset_ctl reset_ctl;
29 	struct clk clk;
30 	struct gpio_desc cd_gpio;	/* Change Detect GPIO */
31 	struct gpio_desc pwr_gpio;	/* Power GPIO */
32 	struct gpio_desc wp_gpio;	/* Write Protect GPIO */
33 	unsigned int version;	/* SDHCI spec. version */
34 	unsigned int clock;	/* Current clock (MHz) */
35 };
36 
37 static void tegra_mmc_set_power(struct tegra_mmc_priv *priv,
38 				unsigned short power)
39 {
40 	u8 pwr = 0;
41 	debug("%s: power = %x\n", __func__, power);
42 
43 	if (power != (unsigned short)-1) {
44 		switch (1 << power) {
45 		case MMC_VDD_165_195:
46 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V1_8;
47 			break;
48 		case MMC_VDD_29_30:
49 		case MMC_VDD_30_31:
50 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V3_0;
51 			break;
52 		case MMC_VDD_32_33:
53 		case MMC_VDD_33_34:
54 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V3_3;
55 			break;
56 		}
57 	}
58 	debug("%s: pwr = %X\n", __func__, pwr);
59 
60 	/* Set the bus voltage first (if any) */
61 	writeb(pwr, &priv->reg->pwrcon);
62 	if (pwr == 0)
63 		return;
64 
65 	/* Now enable bus power */
66 	pwr |= TEGRA_MMC_PWRCTL_SD_BUS_POWER;
67 	writeb(pwr, &priv->reg->pwrcon);
68 }
69 
70 static void tegra_mmc_prepare_data(struct tegra_mmc_priv *priv,
71 				   struct mmc_data *data,
72 				   struct bounce_buffer *bbstate)
73 {
74 	unsigned char ctrl;
75 
76 
77 	debug("buf: %p (%p), data->blocks: %u, data->blocksize: %u\n",
78 		bbstate->bounce_buffer, bbstate->user_buffer, data->blocks,
79 		data->blocksize);
80 
81 	writel((u32)(unsigned long)bbstate->bounce_buffer, &priv->reg->sysad);
82 	/*
83 	 * DMASEL[4:3]
84 	 * 00 = Selects SDMA
85 	 * 01 = Reserved
86 	 * 10 = Selects 32-bit Address ADMA2
87 	 * 11 = Selects 64-bit Address ADMA2
88 	 */
89 	ctrl = readb(&priv->reg->hostctl);
90 	ctrl &= ~TEGRA_MMC_HOSTCTL_DMASEL_MASK;
91 	ctrl |= TEGRA_MMC_HOSTCTL_DMASEL_SDMA;
92 	writeb(ctrl, &priv->reg->hostctl);
93 
94 	/* We do not handle DMA boundaries, so set it to max (512 KiB) */
95 	writew((7 << 12) | (data->blocksize & 0xFFF), &priv->reg->blksize);
96 	writew(data->blocks, &priv->reg->blkcnt);
97 }
98 
99 static void tegra_mmc_set_transfer_mode(struct tegra_mmc_priv *priv,
100 					struct mmc_data *data)
101 {
102 	unsigned short mode;
103 	debug(" mmc_set_transfer_mode called\n");
104 	/*
105 	 * TRNMOD
106 	 * MUL1SIN0[5]	: Multi/Single Block Select
107 	 * RD1WT0[4]	: Data Transfer Direction Select
108 	 *	1 = read
109 	 *	0 = write
110 	 * ENACMD12[2]	: Auto CMD12 Enable
111 	 * ENBLKCNT[1]	: Block Count Enable
112 	 * ENDMA[0]	: DMA Enable
113 	 */
114 	mode = (TEGRA_MMC_TRNMOD_DMA_ENABLE |
115 		TEGRA_MMC_TRNMOD_BLOCK_COUNT_ENABLE);
116 
117 	if (data->blocks > 1)
118 		mode |= TEGRA_MMC_TRNMOD_MULTI_BLOCK_SELECT;
119 
120 	if (data->flags & MMC_DATA_READ)
121 		mode |= TEGRA_MMC_TRNMOD_DATA_XFER_DIR_SEL_READ;
122 
123 	writew(mode, &priv->reg->trnmod);
124 }
125 
126 static int tegra_mmc_wait_inhibit(struct tegra_mmc_priv *priv,
127 				  struct mmc_cmd *cmd,
128 				  struct mmc_data *data,
129 				  unsigned int timeout)
130 {
131 	/*
132 	 * PRNSTS
133 	 * CMDINHDAT[1] : Command Inhibit (DAT)
134 	 * CMDINHCMD[0] : Command Inhibit (CMD)
135 	 */
136 	unsigned int mask = TEGRA_MMC_PRNSTS_CMD_INHIBIT_CMD;
137 
138 	/*
139 	 * We shouldn't wait for data inhibit for stop commands, even
140 	 * though they might use busy signaling
141 	 */
142 	if ((data == NULL) && (cmd->resp_type & MMC_RSP_BUSY))
143 		mask |= TEGRA_MMC_PRNSTS_CMD_INHIBIT_DAT;
144 
145 	while (readl(&priv->reg->prnsts) & mask) {
146 		if (timeout == 0) {
147 			printf("%s: timeout error\n", __func__);
148 			return -1;
149 		}
150 		timeout--;
151 		udelay(1000);
152 	}
153 
154 	return 0;
155 }
156 
157 static int tegra_mmc_send_cmd_bounced(struct udevice *dev, struct mmc_cmd *cmd,
158 				      struct mmc_data *data,
159 				      struct bounce_buffer *bbstate)
160 {
161 	struct tegra_mmc_priv *priv = dev_get_priv(dev);
162 	int flags, i;
163 	int result;
164 	unsigned int mask = 0;
165 	unsigned int retry = 0x100000;
166 	debug(" mmc_send_cmd called\n");
167 
168 	result = tegra_mmc_wait_inhibit(priv, cmd, data, 10 /* ms */);
169 
170 	if (result < 0)
171 		return result;
172 
173 	if (data)
174 		tegra_mmc_prepare_data(priv, data, bbstate);
175 
176 	debug("cmd->arg: %08x\n", cmd->cmdarg);
177 	writel(cmd->cmdarg, &priv->reg->argument);
178 
179 	if (data)
180 		tegra_mmc_set_transfer_mode(priv, data);
181 
182 	if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY))
183 		return -1;
184 
185 	/*
186 	 * CMDREG
187 	 * CMDIDX[13:8]	: Command index
188 	 * DATAPRNT[5]	: Data Present Select
189 	 * ENCMDIDX[4]	: Command Index Check Enable
190 	 * ENCMDCRC[3]	: Command CRC Check Enable
191 	 * RSPTYP[1:0]
192 	 *	00 = No Response
193 	 *	01 = Length 136
194 	 *	10 = Length 48
195 	 *	11 = Length 48 Check busy after response
196 	 */
197 	if (!(cmd->resp_type & MMC_RSP_PRESENT))
198 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_NO_RESPONSE;
199 	else if (cmd->resp_type & MMC_RSP_136)
200 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_136;
201 	else if (cmd->resp_type & MMC_RSP_BUSY)
202 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_48_BUSY;
203 	else
204 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_48;
205 
206 	if (cmd->resp_type & MMC_RSP_CRC)
207 		flags |= TEGRA_MMC_TRNMOD_CMD_CRC_CHECK;
208 	if (cmd->resp_type & MMC_RSP_OPCODE)
209 		flags |= TEGRA_MMC_TRNMOD_CMD_INDEX_CHECK;
210 	if (data)
211 		flags |= TEGRA_MMC_TRNMOD_DATA_PRESENT_SELECT_DATA_TRANSFER;
212 
213 	debug("cmd: %d\n", cmd->cmdidx);
214 
215 	writew((cmd->cmdidx << 8) | flags, &priv->reg->cmdreg);
216 
217 	for (i = 0; i < retry; i++) {
218 		mask = readl(&priv->reg->norintsts);
219 		/* Command Complete */
220 		if (mask & TEGRA_MMC_NORINTSTS_CMD_COMPLETE) {
221 			if (!data)
222 				writel(mask, &priv->reg->norintsts);
223 			break;
224 		}
225 	}
226 
227 	if (i == retry) {
228 		printf("%s: waiting for status update\n", __func__);
229 		writel(mask, &priv->reg->norintsts);
230 		return -ETIMEDOUT;
231 	}
232 
233 	if (mask & TEGRA_MMC_NORINTSTS_CMD_TIMEOUT) {
234 		/* Timeout Error */
235 		debug("timeout: %08x cmd %d\n", mask, cmd->cmdidx);
236 		writel(mask, &priv->reg->norintsts);
237 		return -ETIMEDOUT;
238 	} else if (mask & TEGRA_MMC_NORINTSTS_ERR_INTERRUPT) {
239 		/* Error Interrupt */
240 		debug("error: %08x cmd %d\n", mask, cmd->cmdidx);
241 		writel(mask, &priv->reg->norintsts);
242 		return -1;
243 	}
244 
245 	if (cmd->resp_type & MMC_RSP_PRESENT) {
246 		if (cmd->resp_type & MMC_RSP_136) {
247 			/* CRC is stripped so we need to do some shifting. */
248 			for (i = 0; i < 4; i++) {
249 				unsigned long offset = (unsigned long)
250 					(&priv->reg->rspreg3 - i);
251 				cmd->response[i] = readl(offset) << 8;
252 
253 				if (i != 3) {
254 					cmd->response[i] |=
255 						readb(offset - 1);
256 				}
257 				debug("cmd->resp[%d]: %08x\n",
258 						i, cmd->response[i]);
259 			}
260 		} else if (cmd->resp_type & MMC_RSP_BUSY) {
261 			for (i = 0; i < retry; i++) {
262 				/* PRNTDATA[23:20] : DAT[3:0] Line Signal */
263 				if (readl(&priv->reg->prnsts)
264 					& (1 << 20))	/* DAT[0] */
265 					break;
266 			}
267 
268 			if (i == retry) {
269 				printf("%s: card is still busy\n", __func__);
270 				writel(mask, &priv->reg->norintsts);
271 				return -ETIMEDOUT;
272 			}
273 
274 			cmd->response[0] = readl(&priv->reg->rspreg0);
275 			debug("cmd->resp[0]: %08x\n", cmd->response[0]);
276 		} else {
277 			cmd->response[0] = readl(&priv->reg->rspreg0);
278 			debug("cmd->resp[0]: %08x\n", cmd->response[0]);
279 		}
280 	}
281 
282 	if (data) {
283 		unsigned long	start = get_timer(0);
284 
285 		while (1) {
286 			mask = readl(&priv->reg->norintsts);
287 
288 			if (mask & TEGRA_MMC_NORINTSTS_ERR_INTERRUPT) {
289 				/* Error Interrupt */
290 				writel(mask, &priv->reg->norintsts);
291 				printf("%s: error during transfer: 0x%08x\n",
292 						__func__, mask);
293 				return -1;
294 			} else if (mask & TEGRA_MMC_NORINTSTS_DMA_INTERRUPT) {
295 				/*
296 				 * DMA Interrupt, restart the transfer where
297 				 * it was interrupted.
298 				 */
299 				unsigned int address = readl(&priv->reg->sysad);
300 
301 				debug("DMA end\n");
302 				writel(TEGRA_MMC_NORINTSTS_DMA_INTERRUPT,
303 				       &priv->reg->norintsts);
304 				writel(address, &priv->reg->sysad);
305 			} else if (mask & TEGRA_MMC_NORINTSTS_XFER_COMPLETE) {
306 				/* Transfer Complete */
307 				debug("r/w is done\n");
308 				break;
309 			} else if (get_timer(start) > 8000UL) {
310 				writel(mask, &priv->reg->norintsts);
311 				printf("%s: MMC Timeout\n"
312 				       "    Interrupt status        0x%08x\n"
313 				       "    Interrupt status enable 0x%08x\n"
314 				       "    Interrupt signal enable 0x%08x\n"
315 				       "    Present status          0x%08x\n",
316 				       __func__, mask,
317 				       readl(&priv->reg->norintstsen),
318 				       readl(&priv->reg->norintsigen),
319 				       readl(&priv->reg->prnsts));
320 				return -1;
321 			}
322 		}
323 		writel(mask, &priv->reg->norintsts);
324 	}
325 
326 	udelay(1000);
327 	return 0;
328 }
329 
330 static int tegra_mmc_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
331 			      struct mmc_data *data)
332 {
333 	void *buf;
334 	unsigned int bbflags;
335 	size_t len;
336 	struct bounce_buffer bbstate;
337 	int ret;
338 
339 	if (data) {
340 		if (data->flags & MMC_DATA_READ) {
341 			buf = data->dest;
342 			bbflags = GEN_BB_WRITE;
343 		} else {
344 			buf = (void *)data->src;
345 			bbflags = GEN_BB_READ;
346 		}
347 		len = data->blocks * data->blocksize;
348 
349 		bounce_buffer_start(&bbstate, buf, len, bbflags);
350 	}
351 
352 	ret = tegra_mmc_send_cmd_bounced(dev, cmd, data, &bbstate);
353 
354 	if (data)
355 		bounce_buffer_stop(&bbstate);
356 
357 	return ret;
358 }
359 
360 static void tegra_mmc_change_clock(struct tegra_mmc_priv *priv, uint clock)
361 {
362 	ulong rate;
363 	int div;
364 	unsigned short clk;
365 	unsigned long timeout;
366 
367 	debug(" mmc_change_clock called\n");
368 
369 	/*
370 	 * Change Tegra SDMMCx clock divisor here. Source is PLLP_OUT0
371 	 */
372 	if (clock == 0)
373 		goto out;
374 
375 	rate = clk_set_rate(&priv->clk, clock);
376 	div = (rate + clock - 1) / clock;
377 	debug("div = %d\n", div);
378 
379 	writew(0, &priv->reg->clkcon);
380 
381 	/*
382 	 * CLKCON
383 	 * SELFREQ[15:8]	: base clock divided by value
384 	 * ENSDCLK[2]		: SD Clock Enable
385 	 * STBLINTCLK[1]	: Internal Clock Stable
386 	 * ENINTCLK[0]		: Internal Clock Enable
387 	 */
388 	div >>= 1;
389 	clk = ((div << TEGRA_MMC_CLKCON_SDCLK_FREQ_SEL_SHIFT) |
390 	       TEGRA_MMC_CLKCON_INTERNAL_CLOCK_ENABLE);
391 	writew(clk, &priv->reg->clkcon);
392 
393 	/* Wait max 10 ms */
394 	timeout = 10;
395 	while (!(readw(&priv->reg->clkcon) &
396 		 TEGRA_MMC_CLKCON_INTERNAL_CLOCK_STABLE)) {
397 		if (timeout == 0) {
398 			printf("%s: timeout error\n", __func__);
399 			return;
400 		}
401 		timeout--;
402 		udelay(1000);
403 	}
404 
405 	clk |= TEGRA_MMC_CLKCON_SD_CLOCK_ENABLE;
406 	writew(clk, &priv->reg->clkcon);
407 
408 	debug("mmc_change_clock: clkcon = %08X\n", clk);
409 
410 out:
411 	priv->clock = clock;
412 }
413 
414 static int tegra_mmc_set_ios(struct udevice *dev)
415 {
416 	struct tegra_mmc_priv *priv = dev_get_priv(dev);
417 	struct mmc *mmc = mmc_get_mmc_dev(dev);
418 	unsigned char ctrl;
419 	debug(" mmc_set_ios called\n");
420 
421 	debug("bus_width: %x, clock: %d\n", mmc->bus_width, mmc->clock);
422 
423 	/* Change clock first */
424 	tegra_mmc_change_clock(priv, mmc->clock);
425 
426 	ctrl = readb(&priv->reg->hostctl);
427 
428 	/*
429 	 * WIDE8[5]
430 	 * 0 = Depend on WIDE4
431 	 * 1 = 8-bit mode
432 	 * WIDE4[1]
433 	 * 1 = 4-bit mode
434 	 * 0 = 1-bit mode
435 	 */
436 	if (mmc->bus_width == 8)
437 		ctrl |= (1 << 5);
438 	else if (mmc->bus_width == 4)
439 		ctrl |= (1 << 1);
440 	else
441 		ctrl &= ~(1 << 1 | 1 << 5);
442 
443 	writeb(ctrl, &priv->reg->hostctl);
444 	debug("mmc_set_ios: hostctl = %08X\n", ctrl);
445 
446 	return 0;
447 }
448 
449 static void tegra_mmc_pad_init(struct tegra_mmc_priv *priv)
450 {
451 #if defined(CONFIG_TEGRA30)
452 	u32 val;
453 
454 	debug("%s: sdmmc address = %08x\n", __func__, (unsigned int)priv->reg);
455 
456 	/* Set the pad drive strength for SDMMC1 or 3 only */
457 	if (priv->reg != (void *)0x78000000 &&
458 	    priv->reg != (void *)0x78000400) {
459 		debug("%s: settings are only valid for SDMMC1/SDMMC3!\n",
460 		      __func__);
461 		return;
462 	}
463 
464 	val = readl(&priv->reg->sdmemcmppadctl);
465 	val &= 0xFFFFFFF0;
466 	val |= MEMCOMP_PADCTRL_VREF;
467 	writel(val, &priv->reg->sdmemcmppadctl);
468 
469 	val = readl(&priv->reg->autocalcfg);
470 	val &= 0xFFFF0000;
471 	val |= AUTO_CAL_PU_OFFSET | AUTO_CAL_PD_OFFSET | AUTO_CAL_ENABLED;
472 	writel(val, &priv->reg->autocalcfg);
473 #endif
474 }
475 
476 static void tegra_mmc_reset(struct tegra_mmc_priv *priv, struct mmc *mmc)
477 {
478 	unsigned int timeout;
479 	debug(" mmc_reset called\n");
480 
481 	/*
482 	 * RSTALL[0] : Software reset for all
483 	 * 1 = reset
484 	 * 0 = work
485 	 */
486 	writeb(TEGRA_MMC_SWRST_SW_RESET_FOR_ALL, &priv->reg->swrst);
487 
488 	priv->clock = 0;
489 
490 	/* Wait max 100 ms */
491 	timeout = 100;
492 
493 	/* hw clears the bit when it's done */
494 	while (readb(&priv->reg->swrst) & TEGRA_MMC_SWRST_SW_RESET_FOR_ALL) {
495 		if (timeout == 0) {
496 			printf("%s: timeout error\n", __func__);
497 			return;
498 		}
499 		timeout--;
500 		udelay(1000);
501 	}
502 
503 	/* Set SD bus voltage & enable bus power */
504 	tegra_mmc_set_power(priv, fls(mmc->cfg->voltages) - 1);
505 	debug("%s: power control = %02X, host control = %02X\n", __func__,
506 		readb(&priv->reg->pwrcon), readb(&priv->reg->hostctl));
507 
508 	/* Make sure SDIO pads are set up */
509 	tegra_mmc_pad_init(priv);
510 }
511 
512 static int tegra_mmc_init(struct udevice *dev)
513 {
514 	struct tegra_mmc_priv *priv = dev_get_priv(dev);
515 	struct mmc *mmc = mmc_get_mmc_dev(dev);
516 	unsigned int mask;
517 	debug(" tegra_mmc_init called\n");
518 
519 	tegra_mmc_reset(priv, mmc);
520 
521 #if defined(CONFIG_TEGRA124_MMC_DISABLE_EXT_LOOPBACK)
522 	/*
523 	 * Disable the external clock loopback and use the internal one on
524 	 * SDMMC3 as per the SDMMC_VENDOR_MISC_CNTRL_0 register's SDMMC_SPARE1
525 	 * bits being set to 0xfffd according to the TRM.
526 	 *
527 	 * TODO(marcel.ziswiler@toradex.com): Move to device tree controlled
528 	 * approach once proper kernel integration made it mainline.
529 	 */
530 	if (priv->reg == (void *)0x700b0400) {
531 		mask = readl(&priv->reg->venmiscctl);
532 		mask &= ~TEGRA_MMC_MISCON_ENABLE_EXT_LOOPBACK;
533 		writel(mask, &priv->reg->venmiscctl);
534 	}
535 #endif
536 
537 	priv->version = readw(&priv->reg->hcver);
538 	debug("host version = %x\n", priv->version);
539 
540 	/* mask all */
541 	writel(0xffffffff, &priv->reg->norintstsen);
542 	writel(0xffffffff, &priv->reg->norintsigen);
543 
544 	writeb(0xe, &priv->reg->timeoutcon);	/* TMCLK * 2^27 */
545 	/*
546 	 * NORMAL Interrupt Status Enable Register init
547 	 * [5] ENSTABUFRDRDY : Buffer Read Ready Status Enable
548 	 * [4] ENSTABUFWTRDY : Buffer write Ready Status Enable
549 	 * [3] ENSTADMAINT   : DMA boundary interrupt
550 	 * [1] ENSTASTANSCMPLT : Transfre Complete Status Enable
551 	 * [0] ENSTACMDCMPLT : Command Complete Status Enable
552 	*/
553 	mask = readl(&priv->reg->norintstsen);
554 	mask &= ~(0xffff);
555 	mask |= (TEGRA_MMC_NORINTSTSEN_CMD_COMPLETE |
556 		 TEGRA_MMC_NORINTSTSEN_XFER_COMPLETE |
557 		 TEGRA_MMC_NORINTSTSEN_DMA_INTERRUPT |
558 		 TEGRA_MMC_NORINTSTSEN_BUFFER_WRITE_READY |
559 		 TEGRA_MMC_NORINTSTSEN_BUFFER_READ_READY);
560 	writel(mask, &priv->reg->norintstsen);
561 
562 	/*
563 	 * NORMAL Interrupt Signal Enable Register init
564 	 * [1] ENSTACMDCMPLT : Transfer Complete Signal Enable
565 	 */
566 	mask = readl(&priv->reg->norintsigen);
567 	mask &= ~(0xffff);
568 	mask |= TEGRA_MMC_NORINTSIGEN_XFER_COMPLETE;
569 	writel(mask, &priv->reg->norintsigen);
570 
571 	return 0;
572 }
573 
574 static int tegra_mmc_getcd(struct udevice *dev)
575 {
576 	struct tegra_mmc_priv *priv = dev_get_priv(dev);
577 
578 	debug("tegra_mmc_getcd called\n");
579 
580 	if (dm_gpio_is_valid(&priv->cd_gpio))
581 		return dm_gpio_get_value(&priv->cd_gpio);
582 
583 	return 1;
584 }
585 
586 static const struct dm_mmc_ops tegra_mmc_ops = {
587 	.send_cmd	= tegra_mmc_send_cmd,
588 	.set_ios	= tegra_mmc_set_ios,
589 	.get_cd		= tegra_mmc_getcd,
590 };
591 
592 static int tegra_mmc_probe(struct udevice *dev)
593 {
594 	struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
595 	struct tegra_mmc_plat *plat = dev_get_platdata(dev);
596 	struct tegra_mmc_priv *priv = dev_get_priv(dev);
597 	struct mmc_config *cfg = &plat->cfg;
598 	int bus_width, ret;
599 
600 	cfg->name = dev->name;
601 
602 	bus_width = dev_read_u32_default(dev, "bus-width", 1);
603 
604 	cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34 | MMC_VDD_165_195;
605 	cfg->host_caps = 0;
606 	if (bus_width == 8)
607 		cfg->host_caps |= MMC_MODE_8BIT;
608 	if (bus_width >= 4)
609 		cfg->host_caps |= MMC_MODE_4BIT;
610 	cfg->host_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS;
611 
612 	/*
613 	 * min freq is for card identification, and is the highest
614 	 *  low-speed SDIO card frequency (actually 400KHz)
615 	 * max freq is highest HS eMMC clock as per the SD/MMC spec
616 	 *  (actually 52MHz)
617 	 */
618 	cfg->f_min = 375000;
619 	cfg->f_max = 48000000;
620 
621 	cfg->b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
622 
623 	priv->reg = (void *)dev_read_addr(dev);
624 
625 	ret = reset_get_by_name(dev, "sdhci", &priv->reset_ctl);
626 	if (ret) {
627 		debug("reset_get_by_name() failed: %d\n", ret);
628 		return ret;
629 	}
630 	ret = clk_get_by_index(dev, 0, &priv->clk);
631 	if (ret) {
632 		debug("clk_get_by_index() failed: %d\n", ret);
633 		return ret;
634 	}
635 
636 	ret = reset_assert(&priv->reset_ctl);
637 	if (ret)
638 		return ret;
639 	ret = clk_enable(&priv->clk);
640 	if (ret)
641 		return ret;
642 	ret = clk_set_rate(&priv->clk, 20000000);
643 	if (IS_ERR_VALUE(ret))
644 		return ret;
645 	ret = reset_deassert(&priv->reset_ctl);
646 	if (ret)
647 		return ret;
648 
649 	/* These GPIOs are optional */
650 	gpio_request_by_name(dev, "cd-gpios", 0, &priv->cd_gpio, GPIOD_IS_IN);
651 	gpio_request_by_name(dev, "wp-gpios", 0, &priv->wp_gpio, GPIOD_IS_IN);
652 	gpio_request_by_name(dev, "power-gpios", 0, &priv->pwr_gpio,
653 			     GPIOD_IS_OUT);
654 	if (dm_gpio_is_valid(&priv->pwr_gpio))
655 		dm_gpio_set_value(&priv->pwr_gpio, 1);
656 
657 	upriv->mmc = &plat->mmc;
658 
659 	return tegra_mmc_init(dev);
660 }
661 
662 static int tegra_mmc_bind(struct udevice *dev)
663 {
664 	struct tegra_mmc_plat *plat = dev_get_platdata(dev);
665 
666 	return mmc_bind(dev, &plat->mmc, &plat->cfg);
667 }
668 
669 static const struct udevice_id tegra_mmc_ids[] = {
670 	{ .compatible = "nvidia,tegra20-sdhci" },
671 	{ .compatible = "nvidia,tegra30-sdhci" },
672 	{ .compatible = "nvidia,tegra114-sdhci" },
673 	{ .compatible = "nvidia,tegra124-sdhci" },
674 	{ .compatible = "nvidia,tegra210-sdhci" },
675 	{ .compatible = "nvidia,tegra186-sdhci" },
676 	{ }
677 };
678 
679 U_BOOT_DRIVER(tegra_mmc_drv) = {
680 	.name		= "tegra_mmc",
681 	.id		= UCLASS_MMC,
682 	.of_match	= tegra_mmc_ids,
683 	.bind		= tegra_mmc_bind,
684 	.probe		= tegra_mmc_probe,
685 	.ops		= &tegra_mmc_ops,
686 	.platdata_auto_alloc_size = sizeof(struct tegra_mmc_plat),
687 	.priv_auto_alloc_size = sizeof(struct tegra_mmc_priv),
688 };
689