xref: /openbmc/u-boot/drivers/mmc/tegra_mmc.c (revision 68fbc0e6)
1 /*
2  * (C) Copyright 2009 SAMSUNG Electronics
3  * Minkyu Kang <mk7.kang@samsung.com>
4  * Jaehoon Chung <jh80.chung@samsung.com>
5  * Portions Copyright 2011-2013 NVIDIA Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 
22 #include <bouncebuf.h>
23 #include <common.h>
24 #include <asm/gpio.h>
25 #include <asm/io.h>
26 #include <asm/arch/clock.h>
27 #include <asm/arch-tegra/clk_rst.h>
28 #include <asm/arch-tegra/tegra_mmc.h>
29 #include <mmc.h>
30 
31 DECLARE_GLOBAL_DATA_PTR;
32 
33 struct mmc mmc_dev[MAX_HOSTS];
34 struct mmc_host mmc_host[MAX_HOSTS];
35 
36 #ifndef CONFIG_OF_CONTROL
37 #error "Please enable device tree support to use this driver"
38 #endif
39 
40 static void mmc_set_power(struct mmc_host *host, unsigned short power)
41 {
42 	u8 pwr = 0;
43 	debug("%s: power = %x\n", __func__, power);
44 
45 	if (power != (unsigned short)-1) {
46 		switch (1 << power) {
47 		case MMC_VDD_165_195:
48 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V1_8;
49 			break;
50 		case MMC_VDD_29_30:
51 		case MMC_VDD_30_31:
52 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V3_0;
53 			break;
54 		case MMC_VDD_32_33:
55 		case MMC_VDD_33_34:
56 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V3_3;
57 			break;
58 		}
59 	}
60 	debug("%s: pwr = %X\n", __func__, pwr);
61 
62 	/* Set the bus voltage first (if any) */
63 	writeb(pwr, &host->reg->pwrcon);
64 	if (pwr == 0)
65 		return;
66 
67 	/* Now enable bus power */
68 	pwr |= TEGRA_MMC_PWRCTL_SD_BUS_POWER;
69 	writeb(pwr, &host->reg->pwrcon);
70 }
71 
72 static void mmc_prepare_data(struct mmc_host *host, struct mmc_data *data,
73 				struct bounce_buffer *bbstate)
74 {
75 	unsigned char ctrl;
76 
77 
78 	debug("buf: %p (%p), data->blocks: %u, data->blocksize: %u\n",
79 		bbstate->bounce_buffer, bbstate->user_buffer, data->blocks,
80 		data->blocksize);
81 
82 	writel((u32)bbstate->bounce_buffer, &host->reg->sysad);
83 	/*
84 	 * DMASEL[4:3]
85 	 * 00 = Selects SDMA
86 	 * 01 = Reserved
87 	 * 10 = Selects 32-bit Address ADMA2
88 	 * 11 = Selects 64-bit Address ADMA2
89 	 */
90 	ctrl = readb(&host->reg->hostctl);
91 	ctrl &= ~TEGRA_MMC_HOSTCTL_DMASEL_MASK;
92 	ctrl |= TEGRA_MMC_HOSTCTL_DMASEL_SDMA;
93 	writeb(ctrl, &host->reg->hostctl);
94 
95 	/* We do not handle DMA boundaries, so set it to max (512 KiB) */
96 	writew((7 << 12) | (data->blocksize & 0xFFF), &host->reg->blksize);
97 	writew(data->blocks, &host->reg->blkcnt);
98 }
99 
100 static void mmc_set_transfer_mode(struct mmc_host *host, 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, &host->reg->trnmod);
124 }
125 
126 static int mmc_wait_inhibit(struct mmc_host *host,
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(&host->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 mmc_send_cmd_bounced(struct mmc *mmc, struct mmc_cmd *cmd,
158 			struct mmc_data *data, struct bounce_buffer *bbstate)
159 {
160 	struct mmc_host *host = (struct mmc_host *)mmc->priv;
161 	int flags, i;
162 	int result;
163 	unsigned int mask = 0;
164 	unsigned int retry = 0x100000;
165 	debug(" mmc_send_cmd called\n");
166 
167 	result = mmc_wait_inhibit(host, cmd, data, 10 /* ms */);
168 
169 	if (result < 0)
170 		return result;
171 
172 	if (data)
173 		mmc_prepare_data(host, data, bbstate);
174 
175 	debug("cmd->arg: %08x\n", cmd->cmdarg);
176 	writel(cmd->cmdarg, &host->reg->argument);
177 
178 	if (data)
179 		mmc_set_transfer_mode(host, data);
180 
181 	if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY))
182 		return -1;
183 
184 	/*
185 	 * CMDREG
186 	 * CMDIDX[13:8]	: Command index
187 	 * DATAPRNT[5]	: Data Present Select
188 	 * ENCMDIDX[4]	: Command Index Check Enable
189 	 * ENCMDCRC[3]	: Command CRC Check Enable
190 	 * RSPTYP[1:0]
191 	 *	00 = No Response
192 	 *	01 = Length 136
193 	 *	10 = Length 48
194 	 *	11 = Length 48 Check busy after response
195 	 */
196 	if (!(cmd->resp_type & MMC_RSP_PRESENT))
197 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_NO_RESPONSE;
198 	else if (cmd->resp_type & MMC_RSP_136)
199 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_136;
200 	else if (cmd->resp_type & MMC_RSP_BUSY)
201 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_48_BUSY;
202 	else
203 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_48;
204 
205 	if (cmd->resp_type & MMC_RSP_CRC)
206 		flags |= TEGRA_MMC_TRNMOD_CMD_CRC_CHECK;
207 	if (cmd->resp_type & MMC_RSP_OPCODE)
208 		flags |= TEGRA_MMC_TRNMOD_CMD_INDEX_CHECK;
209 	if (data)
210 		flags |= TEGRA_MMC_TRNMOD_DATA_PRESENT_SELECT_DATA_TRANSFER;
211 
212 	debug("cmd: %d\n", cmd->cmdidx);
213 
214 	writew((cmd->cmdidx << 8) | flags, &host->reg->cmdreg);
215 
216 	for (i = 0; i < retry; i++) {
217 		mask = readl(&host->reg->norintsts);
218 		/* Command Complete */
219 		if (mask & TEGRA_MMC_NORINTSTS_CMD_COMPLETE) {
220 			if (!data)
221 				writel(mask, &host->reg->norintsts);
222 			break;
223 		}
224 	}
225 
226 	if (i == retry) {
227 		printf("%s: waiting for status update\n", __func__);
228 		writel(mask, &host->reg->norintsts);
229 		return TIMEOUT;
230 	}
231 
232 	if (mask & TEGRA_MMC_NORINTSTS_CMD_TIMEOUT) {
233 		/* Timeout Error */
234 		debug("timeout: %08x cmd %d\n", mask, cmd->cmdidx);
235 		writel(mask, &host->reg->norintsts);
236 		return TIMEOUT;
237 	} else if (mask & TEGRA_MMC_NORINTSTS_ERR_INTERRUPT) {
238 		/* Error Interrupt */
239 		debug("error: %08x cmd %d\n", mask, cmd->cmdidx);
240 		writel(mask, &host->reg->norintsts);
241 		return -1;
242 	}
243 
244 	if (cmd->resp_type & MMC_RSP_PRESENT) {
245 		if (cmd->resp_type & MMC_RSP_136) {
246 			/* CRC is stripped so we need to do some shifting. */
247 			for (i = 0; i < 4; i++) {
248 				unsigned int offset =
249 					(unsigned int)(&host->reg->rspreg3 - i);
250 				cmd->response[i] = readl(offset) << 8;
251 
252 				if (i != 3) {
253 					cmd->response[i] |=
254 						readb(offset - 1);
255 				}
256 				debug("cmd->resp[%d]: %08x\n",
257 						i, cmd->response[i]);
258 			}
259 		} else if (cmd->resp_type & MMC_RSP_BUSY) {
260 			for (i = 0; i < retry; i++) {
261 				/* PRNTDATA[23:20] : DAT[3:0] Line Signal */
262 				if (readl(&host->reg->prnsts)
263 					& (1 << 20))	/* DAT[0] */
264 					break;
265 			}
266 
267 			if (i == retry) {
268 				printf("%s: card is still busy\n", __func__);
269 				writel(mask, &host->reg->norintsts);
270 				return TIMEOUT;
271 			}
272 
273 			cmd->response[0] = readl(&host->reg->rspreg0);
274 			debug("cmd->resp[0]: %08x\n", cmd->response[0]);
275 		} else {
276 			cmd->response[0] = readl(&host->reg->rspreg0);
277 			debug("cmd->resp[0]: %08x\n", cmd->response[0]);
278 		}
279 	}
280 
281 	if (data) {
282 		unsigned long	start = get_timer(0);
283 
284 		while (1) {
285 			mask = readl(&host->reg->norintsts);
286 
287 			if (mask & TEGRA_MMC_NORINTSTS_ERR_INTERRUPT) {
288 				/* Error Interrupt */
289 				writel(mask, &host->reg->norintsts);
290 				printf("%s: error during transfer: 0x%08x\n",
291 						__func__, mask);
292 				return -1;
293 			} else if (mask & TEGRA_MMC_NORINTSTS_DMA_INTERRUPT) {
294 				/*
295 				 * DMA Interrupt, restart the transfer where
296 				 * it was interrupted.
297 				 */
298 				unsigned int address = readl(&host->reg->sysad);
299 
300 				debug("DMA end\n");
301 				writel(TEGRA_MMC_NORINTSTS_DMA_INTERRUPT,
302 				       &host->reg->norintsts);
303 				writel(address, &host->reg->sysad);
304 			} else if (mask & TEGRA_MMC_NORINTSTS_XFER_COMPLETE) {
305 				/* Transfer Complete */
306 				debug("r/w is done\n");
307 				break;
308 			} else if (get_timer(start) > 2000UL) {
309 				writel(mask, &host->reg->norintsts);
310 				printf("%s: MMC Timeout\n"
311 				       "    Interrupt status        0x%08x\n"
312 				       "    Interrupt status enable 0x%08x\n"
313 				       "    Interrupt signal enable 0x%08x\n"
314 				       "    Present status          0x%08x\n",
315 				       __func__, mask,
316 				       readl(&host->reg->norintstsen),
317 				       readl(&host->reg->norintsigen),
318 				       readl(&host->reg->prnsts));
319 				return -1;
320 			}
321 		}
322 		writel(mask, &host->reg->norintsts);
323 	}
324 
325 	udelay(1000);
326 	return 0;
327 }
328 
329 static int mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
330 			struct mmc_data *data)
331 {
332 	void *buf;
333 	unsigned int bbflags;
334 	size_t len;
335 	struct bounce_buffer bbstate;
336 	int ret;
337 
338 	if (data) {
339 		if (data->flags & MMC_DATA_READ) {
340 			buf = data->dest;
341 			bbflags = GEN_BB_WRITE;
342 		} else {
343 			buf = (void *)data->src;
344 			bbflags = GEN_BB_READ;
345 		}
346 		len = data->blocks * data->blocksize;
347 
348 		bounce_buffer_start(&bbstate, buf, len, bbflags);
349 	}
350 
351 	ret = mmc_send_cmd_bounced(mmc, cmd, data, &bbstate);
352 
353 	if (data)
354 		bounce_buffer_stop(&bbstate);
355 
356 	return ret;
357 }
358 
359 static void mmc_change_clock(struct mmc_host *host, uint clock)
360 {
361 	int div;
362 	unsigned short clk;
363 	unsigned long timeout;
364 
365 	debug(" mmc_change_clock called\n");
366 
367 	/*
368 	 * Change Tegra SDMMCx clock divisor here. Source is PLLP_OUT0
369 	 */
370 	if (clock == 0)
371 		goto out;
372 	clock_adjust_periph_pll_div(host->mmc_id, CLOCK_ID_PERIPH, clock,
373 				    &div);
374 	debug("div = %d\n", div);
375 
376 	writew(0, &host->reg->clkcon);
377 
378 	/*
379 	 * CLKCON
380 	 * SELFREQ[15:8]	: base clock divided by value
381 	 * ENSDCLK[2]		: SD Clock Enable
382 	 * STBLINTCLK[1]	: Internal Clock Stable
383 	 * ENINTCLK[0]		: Internal Clock Enable
384 	 */
385 	div >>= 1;
386 	clk = ((div << TEGRA_MMC_CLKCON_SDCLK_FREQ_SEL_SHIFT) |
387 	       TEGRA_MMC_CLKCON_INTERNAL_CLOCK_ENABLE);
388 	writew(clk, &host->reg->clkcon);
389 
390 	/* Wait max 10 ms */
391 	timeout = 10;
392 	while (!(readw(&host->reg->clkcon) &
393 		 TEGRA_MMC_CLKCON_INTERNAL_CLOCK_STABLE)) {
394 		if (timeout == 0) {
395 			printf("%s: timeout error\n", __func__);
396 			return;
397 		}
398 		timeout--;
399 		udelay(1000);
400 	}
401 
402 	clk |= TEGRA_MMC_CLKCON_SD_CLOCK_ENABLE;
403 	writew(clk, &host->reg->clkcon);
404 
405 	debug("mmc_change_clock: clkcon = %08X\n", clk);
406 
407 out:
408 	host->clock = clock;
409 }
410 
411 static void mmc_set_ios(struct mmc *mmc)
412 {
413 	struct mmc_host *host = mmc->priv;
414 	unsigned char ctrl;
415 	debug(" mmc_set_ios called\n");
416 
417 	debug("bus_width: %x, clock: %d\n", mmc->bus_width, mmc->clock);
418 
419 	/* Change clock first */
420 	mmc_change_clock(host, mmc->clock);
421 
422 	ctrl = readb(&host->reg->hostctl);
423 
424 	/*
425 	 * WIDE8[5]
426 	 * 0 = Depend on WIDE4
427 	 * 1 = 8-bit mode
428 	 * WIDE4[1]
429 	 * 1 = 4-bit mode
430 	 * 0 = 1-bit mode
431 	 */
432 	if (mmc->bus_width == 8)
433 		ctrl |= (1 << 5);
434 	else if (mmc->bus_width == 4)
435 		ctrl |= (1 << 1);
436 	else
437 		ctrl &= ~(1 << 1);
438 
439 	writeb(ctrl, &host->reg->hostctl);
440 	debug("mmc_set_ios: hostctl = %08X\n", ctrl);
441 }
442 
443 static void mmc_reset(struct mmc_host *host, struct mmc *mmc)
444 {
445 	unsigned int timeout;
446 	debug(" mmc_reset called\n");
447 
448 	/*
449 	 * RSTALL[0] : Software reset for all
450 	 * 1 = reset
451 	 * 0 = work
452 	 */
453 	writeb(TEGRA_MMC_SWRST_SW_RESET_FOR_ALL, &host->reg->swrst);
454 
455 	host->clock = 0;
456 
457 	/* Wait max 100 ms */
458 	timeout = 100;
459 
460 	/* hw clears the bit when it's done */
461 	while (readb(&host->reg->swrst) & TEGRA_MMC_SWRST_SW_RESET_FOR_ALL) {
462 		if (timeout == 0) {
463 			printf("%s: timeout error\n", __func__);
464 			return;
465 		}
466 		timeout--;
467 		udelay(1000);
468 	}
469 
470 	/* Set SD bus voltage & enable bus power */
471 	mmc_set_power(host, fls(mmc->voltages) - 1);
472 	debug("%s: power control = %02X, host control = %02X\n", __func__,
473 		readb(&host->reg->pwrcon), readb(&host->reg->hostctl));
474 
475 	/* Make sure SDIO pads are set up */
476 	pad_init_mmc(host);
477 }
478 
479 static int mmc_core_init(struct mmc *mmc)
480 {
481 	struct mmc_host *host = (struct mmc_host *)mmc->priv;
482 	unsigned int mask;
483 	debug(" mmc_core_init called\n");
484 
485 	mmc_reset(host, mmc);
486 
487 	host->version = readw(&host->reg->hcver);
488 	debug("host version = %x\n", host->version);
489 
490 	/* mask all */
491 	writel(0xffffffff, &host->reg->norintstsen);
492 	writel(0xffffffff, &host->reg->norintsigen);
493 
494 	writeb(0xe, &host->reg->timeoutcon);	/* TMCLK * 2^27 */
495 	/*
496 	 * NORMAL Interrupt Status Enable Register init
497 	 * [5] ENSTABUFRDRDY : Buffer Read Ready Status Enable
498 	 * [4] ENSTABUFWTRDY : Buffer write Ready Status Enable
499 	 * [3] ENSTADMAINT   : DMA boundary interrupt
500 	 * [1] ENSTASTANSCMPLT : Transfre Complete Status Enable
501 	 * [0] ENSTACMDCMPLT : Command Complete Status Enable
502 	*/
503 	mask = readl(&host->reg->norintstsen);
504 	mask &= ~(0xffff);
505 	mask |= (TEGRA_MMC_NORINTSTSEN_CMD_COMPLETE |
506 		 TEGRA_MMC_NORINTSTSEN_XFER_COMPLETE |
507 		 TEGRA_MMC_NORINTSTSEN_DMA_INTERRUPT |
508 		 TEGRA_MMC_NORINTSTSEN_BUFFER_WRITE_READY |
509 		 TEGRA_MMC_NORINTSTSEN_BUFFER_READ_READY);
510 	writel(mask, &host->reg->norintstsen);
511 
512 	/*
513 	 * NORMAL Interrupt Signal Enable Register init
514 	 * [1] ENSTACMDCMPLT : Transfer Complete Signal Enable
515 	 */
516 	mask = readl(&host->reg->norintsigen);
517 	mask &= ~(0xffff);
518 	mask |= TEGRA_MMC_NORINTSIGEN_XFER_COMPLETE;
519 	writel(mask, &host->reg->norintsigen);
520 
521 	return 0;
522 }
523 
524 int tegra_mmc_getcd(struct mmc *mmc)
525 {
526 	struct mmc_host *host = (struct mmc_host *)mmc->priv;
527 
528 	debug("tegra_mmc_getcd called\n");
529 
530 	if (fdt_gpio_isvalid(&host->cd_gpio))
531 		return fdtdec_get_gpio(&host->cd_gpio);
532 
533 	return 1;
534 }
535 
536 static int do_mmc_init(int dev_index)
537 {
538 	struct mmc_host *host;
539 	char gpusage[12]; /* "SD/MMCn PWR" or "SD/MMCn CD" */
540 	struct mmc *mmc;
541 
542 	/* DT should have been read & host config filled in */
543 	host = &mmc_host[dev_index];
544 	if (!host->enabled)
545 		return -1;
546 
547 	debug(" do_mmc_init: index %d, bus width %d "
548 		"pwr_gpio %d cd_gpio %d\n",
549 		dev_index, host->width,
550 		host->pwr_gpio.gpio, host->cd_gpio.gpio);
551 
552 	host->clock = 0;
553 	clock_start_periph_pll(host->mmc_id, CLOCK_ID_PERIPH, 20000000);
554 
555 	if (fdt_gpio_isvalid(&host->pwr_gpio)) {
556 		sprintf(gpusage, "SD/MMC%d PWR", dev_index);
557 		gpio_request(host->pwr_gpio.gpio, gpusage);
558 		gpio_direction_output(host->pwr_gpio.gpio, 1);
559 		debug(" Power GPIO name = %s\n", host->pwr_gpio.name);
560 	}
561 
562 	if (fdt_gpio_isvalid(&host->cd_gpio)) {
563 		sprintf(gpusage, "SD/MMC%d CD", dev_index);
564 		gpio_request(host->cd_gpio.gpio, gpusage);
565 		gpio_direction_input(host->cd_gpio.gpio);
566 		debug(" CD GPIO name = %s\n", host->cd_gpio.name);
567 	}
568 
569 	mmc = &mmc_dev[dev_index];
570 
571 	sprintf(mmc->name, "Tegra SD/MMC");
572 	mmc->priv = host;
573 	mmc->send_cmd = mmc_send_cmd;
574 	mmc->set_ios = mmc_set_ios;
575 	mmc->init = mmc_core_init;
576 	mmc->getcd = tegra_mmc_getcd;
577 	mmc->getwp = NULL;
578 
579 	mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34 | MMC_VDD_165_195;
580 	mmc->host_caps = 0;
581 	if (host->width == 8)
582 		mmc->host_caps |= MMC_MODE_8BIT;
583 	if (host->width >= 4)
584 		mmc->host_caps |= MMC_MODE_4BIT;
585 	mmc->host_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS | MMC_MODE_HC;
586 
587 	/*
588 	 * min freq is for card identification, and is the highest
589 	 *  low-speed SDIO card frequency (actually 400KHz)
590 	 * max freq is highest HS eMMC clock as per the SD/MMC spec
591 	 *  (actually 52MHz)
592 	 */
593 	mmc->f_min = 375000;
594 	mmc->f_max = 48000000;
595 
596 	mmc_register(mmc);
597 
598 	return 0;
599 }
600 
601 /**
602  * Get the host address and peripheral ID for a node.
603  *
604  * @param blob		fdt blob
605  * @param node		Device index (0-3)
606  * @param host		Structure to fill in (reg, width, mmc_id)
607  */
608 static int mmc_get_config(const void *blob, int node, struct mmc_host *host)
609 {
610 	debug("%s: node = %d\n", __func__, node);
611 
612 	host->enabled = fdtdec_get_is_enabled(blob, node);
613 
614 	host->reg = (struct tegra_mmc *)fdtdec_get_addr(blob, node, "reg");
615 	if ((fdt_addr_t)host->reg == FDT_ADDR_T_NONE) {
616 		debug("%s: no sdmmc base reg info found\n", __func__);
617 		return -FDT_ERR_NOTFOUND;
618 	}
619 
620 	host->mmc_id = clock_decode_periph_id(blob, node);
621 	if (host->mmc_id == PERIPH_ID_NONE) {
622 		debug("%s: could not decode periph id\n", __func__);
623 		return -FDT_ERR_NOTFOUND;
624 	}
625 
626 	/*
627 	 * NOTE: mmc->bus_width is determined by mmc.c dynamically.
628 	 * TBD: Override it with this value?
629 	 */
630 	host->width = fdtdec_get_int(blob, node, "bus-width", 0);
631 	if (!host->width)
632 		debug("%s: no sdmmc width found\n", __func__);
633 
634 	/* These GPIOs are optional */
635 	fdtdec_decode_gpio(blob, node, "cd-gpios", &host->cd_gpio);
636 	fdtdec_decode_gpio(blob, node, "wp-gpios", &host->wp_gpio);
637 	fdtdec_decode_gpio(blob, node, "power-gpios", &host->pwr_gpio);
638 
639 	debug("%s: found controller at %p, width = %d, periph_id = %d\n",
640 		__func__, host->reg, host->width, host->mmc_id);
641 	return 0;
642 }
643 
644 /*
645  * Process a list of nodes, adding them to our list of SDMMC ports.
646  *
647  * @param blob          fdt blob
648  * @param node_list     list of nodes to process (any <=0 are ignored)
649  * @param count         number of nodes to process
650  * @return 0 if ok, -1 on error
651  */
652 static int process_nodes(const void *blob, int node_list[], int count)
653 {
654 	struct mmc_host *host;
655 	int i, node;
656 
657 	debug("%s: count = %d\n", __func__, count);
658 
659 	/* build mmc_host[] for each controller */
660 	for (i = 0; i < count; i++) {
661 		node = node_list[i];
662 		if (node <= 0)
663 			continue;
664 
665 		host = &mmc_host[i];
666 		host->id = i;
667 
668 		if (mmc_get_config(blob, node, host)) {
669 			printf("%s: failed to decode dev %d\n",	__func__, i);
670 			return -1;
671 		}
672 		do_mmc_init(i);
673 	}
674 	return 0;
675 }
676 
677 void tegra_mmc_init(void)
678 {
679 	int node_list[MAX_HOSTS], count;
680 	const void *blob = gd->fdt_blob;
681 	debug("%s entry\n", __func__);
682 
683 	/* See if any Tegra30 MMC controllers are present */
684 	count = fdtdec_find_aliases_for_id(blob, "sdhci",
685 		COMPAT_NVIDIA_TEGRA30_SDMMC, node_list, MAX_HOSTS);
686 	debug("%s: count of T30 sdhci nodes is %d\n", __func__, count);
687 	if (process_nodes(blob, node_list, count)) {
688 		printf("%s: Error processing T30 mmc node(s)!\n", __func__);
689 		return;
690 	}
691 
692 	/* Now look for any Tegra20 MMC controllers */
693 	count = fdtdec_find_aliases_for_id(blob, "sdhci",
694 		COMPAT_NVIDIA_TEGRA20_SDMMC, node_list, MAX_HOSTS);
695 	debug("%s: count of T20 sdhci nodes is %d\n", __func__, count);
696 	if (process_nodes(blob, node_list, count)) {
697 		printf("%s: Error processing T20 mmc node(s)!\n", __func__);
698 		return;
699 	}
700 }
701