xref: /openbmc/u-boot/drivers/mmc/tegra_mmc.c (revision 70ad375e)
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  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <bouncebuf.h>
11 #include <common.h>
12 #include <asm/gpio.h>
13 #include <asm/io.h>
14 #include <asm/arch/clock.h>
15 #include <asm/arch-tegra/clk_rst.h>
16 #include <asm/arch-tegra/tegra_mmc.h>
17 #include <mmc.h>
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 struct mmc_host mmc_host[MAX_HOSTS];
22 
23 #ifndef CONFIG_OF_CONTROL
24 #error "Please enable device tree support to use this driver"
25 #endif
26 
27 static void mmc_set_power(struct mmc_host *host, unsigned short power)
28 {
29 	u8 pwr = 0;
30 	debug("%s: power = %x\n", __func__, power);
31 
32 	if (power != (unsigned short)-1) {
33 		switch (1 << power) {
34 		case MMC_VDD_165_195:
35 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V1_8;
36 			break;
37 		case MMC_VDD_29_30:
38 		case MMC_VDD_30_31:
39 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V3_0;
40 			break;
41 		case MMC_VDD_32_33:
42 		case MMC_VDD_33_34:
43 			pwr = TEGRA_MMC_PWRCTL_SD_BUS_VOLTAGE_V3_3;
44 			break;
45 		}
46 	}
47 	debug("%s: pwr = %X\n", __func__, pwr);
48 
49 	/* Set the bus voltage first (if any) */
50 	writeb(pwr, &host->reg->pwrcon);
51 	if (pwr == 0)
52 		return;
53 
54 	/* Now enable bus power */
55 	pwr |= TEGRA_MMC_PWRCTL_SD_BUS_POWER;
56 	writeb(pwr, &host->reg->pwrcon);
57 }
58 
59 static void mmc_prepare_data(struct mmc_host *host, struct mmc_data *data,
60 				struct bounce_buffer *bbstate)
61 {
62 	unsigned char ctrl;
63 
64 
65 	debug("buf: %p (%p), data->blocks: %u, data->blocksize: %u\n",
66 		bbstate->bounce_buffer, bbstate->user_buffer, data->blocks,
67 		data->blocksize);
68 
69 	writel((u32)bbstate->bounce_buffer, &host->reg->sysad);
70 	/*
71 	 * DMASEL[4:3]
72 	 * 00 = Selects SDMA
73 	 * 01 = Reserved
74 	 * 10 = Selects 32-bit Address ADMA2
75 	 * 11 = Selects 64-bit Address ADMA2
76 	 */
77 	ctrl = readb(&host->reg->hostctl);
78 	ctrl &= ~TEGRA_MMC_HOSTCTL_DMASEL_MASK;
79 	ctrl |= TEGRA_MMC_HOSTCTL_DMASEL_SDMA;
80 	writeb(ctrl, &host->reg->hostctl);
81 
82 	/* We do not handle DMA boundaries, so set it to max (512 KiB) */
83 	writew((7 << 12) | (data->blocksize & 0xFFF), &host->reg->blksize);
84 	writew(data->blocks, &host->reg->blkcnt);
85 }
86 
87 static void mmc_set_transfer_mode(struct mmc_host *host, struct mmc_data *data)
88 {
89 	unsigned short mode;
90 	debug(" mmc_set_transfer_mode called\n");
91 	/*
92 	 * TRNMOD
93 	 * MUL1SIN0[5]	: Multi/Single Block Select
94 	 * RD1WT0[4]	: Data Transfer Direction Select
95 	 *	1 = read
96 	 *	0 = write
97 	 * ENACMD12[2]	: Auto CMD12 Enable
98 	 * ENBLKCNT[1]	: Block Count Enable
99 	 * ENDMA[0]	: DMA Enable
100 	 */
101 	mode = (TEGRA_MMC_TRNMOD_DMA_ENABLE |
102 		TEGRA_MMC_TRNMOD_BLOCK_COUNT_ENABLE);
103 
104 	if (data->blocks > 1)
105 		mode |= TEGRA_MMC_TRNMOD_MULTI_BLOCK_SELECT;
106 
107 	if (data->flags & MMC_DATA_READ)
108 		mode |= TEGRA_MMC_TRNMOD_DATA_XFER_DIR_SEL_READ;
109 
110 	writew(mode, &host->reg->trnmod);
111 }
112 
113 static int mmc_wait_inhibit(struct mmc_host *host,
114 			    struct mmc_cmd *cmd,
115 			    struct mmc_data *data,
116 			    unsigned int timeout)
117 {
118 	/*
119 	 * PRNSTS
120 	 * CMDINHDAT[1] : Command Inhibit (DAT)
121 	 * CMDINHCMD[0] : Command Inhibit (CMD)
122 	 */
123 	unsigned int mask = TEGRA_MMC_PRNSTS_CMD_INHIBIT_CMD;
124 
125 	/*
126 	 * We shouldn't wait for data inhibit for stop commands, even
127 	 * though they might use busy signaling
128 	 */
129 	if ((data == NULL) && (cmd->resp_type & MMC_RSP_BUSY))
130 		mask |= TEGRA_MMC_PRNSTS_CMD_INHIBIT_DAT;
131 
132 	while (readl(&host->reg->prnsts) & mask) {
133 		if (timeout == 0) {
134 			printf("%s: timeout error\n", __func__);
135 			return -1;
136 		}
137 		timeout--;
138 		udelay(1000);
139 	}
140 
141 	return 0;
142 }
143 
144 static int mmc_send_cmd_bounced(struct mmc *mmc, struct mmc_cmd *cmd,
145 			struct mmc_data *data, struct bounce_buffer *bbstate)
146 {
147 	struct mmc_host *host = mmc->priv;
148 	int flags, i;
149 	int result;
150 	unsigned int mask = 0;
151 	unsigned int retry = 0x100000;
152 	debug(" mmc_send_cmd called\n");
153 
154 	result = mmc_wait_inhibit(host, cmd, data, 10 /* ms */);
155 
156 	if (result < 0)
157 		return result;
158 
159 	if (data)
160 		mmc_prepare_data(host, data, bbstate);
161 
162 	debug("cmd->arg: %08x\n", cmd->cmdarg);
163 	writel(cmd->cmdarg, &host->reg->argument);
164 
165 	if (data)
166 		mmc_set_transfer_mode(host, data);
167 
168 	if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY))
169 		return -1;
170 
171 	/*
172 	 * CMDREG
173 	 * CMDIDX[13:8]	: Command index
174 	 * DATAPRNT[5]	: Data Present Select
175 	 * ENCMDIDX[4]	: Command Index Check Enable
176 	 * ENCMDCRC[3]	: Command CRC Check Enable
177 	 * RSPTYP[1:0]
178 	 *	00 = No Response
179 	 *	01 = Length 136
180 	 *	10 = Length 48
181 	 *	11 = Length 48 Check busy after response
182 	 */
183 	if (!(cmd->resp_type & MMC_RSP_PRESENT))
184 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_NO_RESPONSE;
185 	else if (cmd->resp_type & MMC_RSP_136)
186 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_136;
187 	else if (cmd->resp_type & MMC_RSP_BUSY)
188 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_48_BUSY;
189 	else
190 		flags = TEGRA_MMC_CMDREG_RESP_TYPE_SELECT_LENGTH_48;
191 
192 	if (cmd->resp_type & MMC_RSP_CRC)
193 		flags |= TEGRA_MMC_TRNMOD_CMD_CRC_CHECK;
194 	if (cmd->resp_type & MMC_RSP_OPCODE)
195 		flags |= TEGRA_MMC_TRNMOD_CMD_INDEX_CHECK;
196 	if (data)
197 		flags |= TEGRA_MMC_TRNMOD_DATA_PRESENT_SELECT_DATA_TRANSFER;
198 
199 	debug("cmd: %d\n", cmd->cmdidx);
200 
201 	writew((cmd->cmdidx << 8) | flags, &host->reg->cmdreg);
202 
203 	for (i = 0; i < retry; i++) {
204 		mask = readl(&host->reg->norintsts);
205 		/* Command Complete */
206 		if (mask & TEGRA_MMC_NORINTSTS_CMD_COMPLETE) {
207 			if (!data)
208 				writel(mask, &host->reg->norintsts);
209 			break;
210 		}
211 	}
212 
213 	if (i == retry) {
214 		printf("%s: waiting for status update\n", __func__);
215 		writel(mask, &host->reg->norintsts);
216 		return TIMEOUT;
217 	}
218 
219 	if (mask & TEGRA_MMC_NORINTSTS_CMD_TIMEOUT) {
220 		/* Timeout Error */
221 		debug("timeout: %08x cmd %d\n", mask, cmd->cmdidx);
222 		writel(mask, &host->reg->norintsts);
223 		return TIMEOUT;
224 	} else if (mask & TEGRA_MMC_NORINTSTS_ERR_INTERRUPT) {
225 		/* Error Interrupt */
226 		debug("error: %08x cmd %d\n", mask, cmd->cmdidx);
227 		writel(mask, &host->reg->norintsts);
228 		return -1;
229 	}
230 
231 	if (cmd->resp_type & MMC_RSP_PRESENT) {
232 		if (cmd->resp_type & MMC_RSP_136) {
233 			/* CRC is stripped so we need to do some shifting. */
234 			for (i = 0; i < 4; i++) {
235 				unsigned int offset =
236 					(unsigned int)(&host->reg->rspreg3 - i);
237 				cmd->response[i] = readl(offset) << 8;
238 
239 				if (i != 3) {
240 					cmd->response[i] |=
241 						readb(offset - 1);
242 				}
243 				debug("cmd->resp[%d]: %08x\n",
244 						i, cmd->response[i]);
245 			}
246 		} else if (cmd->resp_type & MMC_RSP_BUSY) {
247 			for (i = 0; i < retry; i++) {
248 				/* PRNTDATA[23:20] : DAT[3:0] Line Signal */
249 				if (readl(&host->reg->prnsts)
250 					& (1 << 20))	/* DAT[0] */
251 					break;
252 			}
253 
254 			if (i == retry) {
255 				printf("%s: card is still busy\n", __func__);
256 				writel(mask, &host->reg->norintsts);
257 				return TIMEOUT;
258 			}
259 
260 			cmd->response[0] = readl(&host->reg->rspreg0);
261 			debug("cmd->resp[0]: %08x\n", cmd->response[0]);
262 		} else {
263 			cmd->response[0] = readl(&host->reg->rspreg0);
264 			debug("cmd->resp[0]: %08x\n", cmd->response[0]);
265 		}
266 	}
267 
268 	if (data) {
269 		unsigned long	start = get_timer(0);
270 
271 		while (1) {
272 			mask = readl(&host->reg->norintsts);
273 
274 			if (mask & TEGRA_MMC_NORINTSTS_ERR_INTERRUPT) {
275 				/* Error Interrupt */
276 				writel(mask, &host->reg->norintsts);
277 				printf("%s: error during transfer: 0x%08x\n",
278 						__func__, mask);
279 				return -1;
280 			} else if (mask & TEGRA_MMC_NORINTSTS_DMA_INTERRUPT) {
281 				/*
282 				 * DMA Interrupt, restart the transfer where
283 				 * it was interrupted.
284 				 */
285 				unsigned int address = readl(&host->reg->sysad);
286 
287 				debug("DMA end\n");
288 				writel(TEGRA_MMC_NORINTSTS_DMA_INTERRUPT,
289 				       &host->reg->norintsts);
290 				writel(address, &host->reg->sysad);
291 			} else if (mask & TEGRA_MMC_NORINTSTS_XFER_COMPLETE) {
292 				/* Transfer Complete */
293 				debug("r/w is done\n");
294 				break;
295 			} else if (get_timer(start) > 2000UL) {
296 				writel(mask, &host->reg->norintsts);
297 				printf("%s: MMC Timeout\n"
298 				       "    Interrupt status        0x%08x\n"
299 				       "    Interrupt status enable 0x%08x\n"
300 				       "    Interrupt signal enable 0x%08x\n"
301 				       "    Present status          0x%08x\n",
302 				       __func__, mask,
303 				       readl(&host->reg->norintstsen),
304 				       readl(&host->reg->norintsigen),
305 				       readl(&host->reg->prnsts));
306 				return -1;
307 			}
308 		}
309 		writel(mask, &host->reg->norintsts);
310 	}
311 
312 	udelay(1000);
313 	return 0;
314 }
315 
316 static int tegra_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
317 			struct mmc_data *data)
318 {
319 	void *buf;
320 	unsigned int bbflags;
321 	size_t len;
322 	struct bounce_buffer bbstate;
323 	int ret;
324 
325 	if (data) {
326 		if (data->flags & MMC_DATA_READ) {
327 			buf = data->dest;
328 			bbflags = GEN_BB_WRITE;
329 		} else {
330 			buf = (void *)data->src;
331 			bbflags = GEN_BB_READ;
332 		}
333 		len = data->blocks * data->blocksize;
334 
335 		bounce_buffer_start(&bbstate, buf, len, bbflags);
336 	}
337 
338 	ret = mmc_send_cmd_bounced(mmc, cmd, data, &bbstate);
339 
340 	if (data)
341 		bounce_buffer_stop(&bbstate);
342 
343 	return ret;
344 }
345 
346 static void mmc_change_clock(struct mmc_host *host, uint clock)
347 {
348 	int div;
349 	unsigned short clk;
350 	unsigned long timeout;
351 
352 	debug(" mmc_change_clock called\n");
353 
354 	/*
355 	 * Change Tegra SDMMCx clock divisor here. Source is PLLP_OUT0
356 	 */
357 	if (clock == 0)
358 		goto out;
359 	clock_adjust_periph_pll_div(host->mmc_id, CLOCK_ID_PERIPH, clock,
360 				    &div);
361 	debug("div = %d\n", div);
362 
363 	writew(0, &host->reg->clkcon);
364 
365 	/*
366 	 * CLKCON
367 	 * SELFREQ[15:8]	: base clock divided by value
368 	 * ENSDCLK[2]		: SD Clock Enable
369 	 * STBLINTCLK[1]	: Internal Clock Stable
370 	 * ENINTCLK[0]		: Internal Clock Enable
371 	 */
372 	div >>= 1;
373 	clk = ((div << TEGRA_MMC_CLKCON_SDCLK_FREQ_SEL_SHIFT) |
374 	       TEGRA_MMC_CLKCON_INTERNAL_CLOCK_ENABLE);
375 	writew(clk, &host->reg->clkcon);
376 
377 	/* Wait max 10 ms */
378 	timeout = 10;
379 	while (!(readw(&host->reg->clkcon) &
380 		 TEGRA_MMC_CLKCON_INTERNAL_CLOCK_STABLE)) {
381 		if (timeout == 0) {
382 			printf("%s: timeout error\n", __func__);
383 			return;
384 		}
385 		timeout--;
386 		udelay(1000);
387 	}
388 
389 	clk |= TEGRA_MMC_CLKCON_SD_CLOCK_ENABLE;
390 	writew(clk, &host->reg->clkcon);
391 
392 	debug("mmc_change_clock: clkcon = %08X\n", clk);
393 
394 out:
395 	host->clock = clock;
396 }
397 
398 static void tegra_mmc_set_ios(struct mmc *mmc)
399 {
400 	struct mmc_host *host = mmc->priv;
401 	unsigned char ctrl;
402 	debug(" mmc_set_ios called\n");
403 
404 	debug("bus_width: %x, clock: %d\n", mmc->bus_width, mmc->clock);
405 
406 	/* Change clock first */
407 	mmc_change_clock(host, mmc->clock);
408 
409 	ctrl = readb(&host->reg->hostctl);
410 
411 	/*
412 	 * WIDE8[5]
413 	 * 0 = Depend on WIDE4
414 	 * 1 = 8-bit mode
415 	 * WIDE4[1]
416 	 * 1 = 4-bit mode
417 	 * 0 = 1-bit mode
418 	 */
419 	if (mmc->bus_width == 8)
420 		ctrl |= (1 << 5);
421 	else if (mmc->bus_width == 4)
422 		ctrl |= (1 << 1);
423 	else
424 		ctrl &= ~(1 << 1);
425 
426 	writeb(ctrl, &host->reg->hostctl);
427 	debug("mmc_set_ios: hostctl = %08X\n", ctrl);
428 }
429 
430 static void mmc_reset(struct mmc_host *host, struct mmc *mmc)
431 {
432 	unsigned int timeout;
433 	debug(" mmc_reset called\n");
434 
435 	/*
436 	 * RSTALL[0] : Software reset for all
437 	 * 1 = reset
438 	 * 0 = work
439 	 */
440 	writeb(TEGRA_MMC_SWRST_SW_RESET_FOR_ALL, &host->reg->swrst);
441 
442 	host->clock = 0;
443 
444 	/* Wait max 100 ms */
445 	timeout = 100;
446 
447 	/* hw clears the bit when it's done */
448 	while (readb(&host->reg->swrst) & TEGRA_MMC_SWRST_SW_RESET_FOR_ALL) {
449 		if (timeout == 0) {
450 			printf("%s: timeout error\n", __func__);
451 			return;
452 		}
453 		timeout--;
454 		udelay(1000);
455 	}
456 
457 	/* Set SD bus voltage & enable bus power */
458 	mmc_set_power(host, fls(mmc->cfg->voltages) - 1);
459 	debug("%s: power control = %02X, host control = %02X\n", __func__,
460 		readb(&host->reg->pwrcon), readb(&host->reg->hostctl));
461 
462 	/* Make sure SDIO pads are set up */
463 	pad_init_mmc(host);
464 }
465 
466 static int tegra_mmc_core_init(struct mmc *mmc)
467 {
468 	struct mmc_host *host = mmc->priv;
469 	unsigned int mask;
470 	debug(" mmc_core_init called\n");
471 
472 	mmc_reset(host, mmc);
473 
474 	host->version = readw(&host->reg->hcver);
475 	debug("host version = %x\n", host->version);
476 
477 	/* mask all */
478 	writel(0xffffffff, &host->reg->norintstsen);
479 	writel(0xffffffff, &host->reg->norintsigen);
480 
481 	writeb(0xe, &host->reg->timeoutcon);	/* TMCLK * 2^27 */
482 	/*
483 	 * NORMAL Interrupt Status Enable Register init
484 	 * [5] ENSTABUFRDRDY : Buffer Read Ready Status Enable
485 	 * [4] ENSTABUFWTRDY : Buffer write Ready Status Enable
486 	 * [3] ENSTADMAINT   : DMA boundary interrupt
487 	 * [1] ENSTASTANSCMPLT : Transfre Complete Status Enable
488 	 * [0] ENSTACMDCMPLT : Command Complete Status Enable
489 	*/
490 	mask = readl(&host->reg->norintstsen);
491 	mask &= ~(0xffff);
492 	mask |= (TEGRA_MMC_NORINTSTSEN_CMD_COMPLETE |
493 		 TEGRA_MMC_NORINTSTSEN_XFER_COMPLETE |
494 		 TEGRA_MMC_NORINTSTSEN_DMA_INTERRUPT |
495 		 TEGRA_MMC_NORINTSTSEN_BUFFER_WRITE_READY |
496 		 TEGRA_MMC_NORINTSTSEN_BUFFER_READ_READY);
497 	writel(mask, &host->reg->norintstsen);
498 
499 	/*
500 	 * NORMAL Interrupt Signal Enable Register init
501 	 * [1] ENSTACMDCMPLT : Transfer Complete Signal Enable
502 	 */
503 	mask = readl(&host->reg->norintsigen);
504 	mask &= ~(0xffff);
505 	mask |= TEGRA_MMC_NORINTSIGEN_XFER_COMPLETE;
506 	writel(mask, &host->reg->norintsigen);
507 
508 	return 0;
509 }
510 
511 int tegra_mmc_getcd(struct mmc *mmc)
512 {
513 	struct mmc_host *host = mmc->priv;
514 
515 	debug("tegra_mmc_getcd called\n");
516 
517 	if (fdt_gpio_isvalid(&host->cd_gpio))
518 		return fdtdec_get_gpio(&host->cd_gpio);
519 
520 	return 1;
521 }
522 
523 static const struct mmc_ops tegra_mmc_ops = {
524 	.send_cmd	= tegra_mmc_send_cmd,
525 	.set_ios	= tegra_mmc_set_ios,
526 	.init		= tegra_mmc_core_init,
527 	.getcd		= tegra_mmc_getcd,
528 };
529 
530 static int do_mmc_init(int dev_index)
531 {
532 	struct mmc_host *host;
533 	char gpusage[12]; /* "SD/MMCn PWR" or "SD/MMCn CD" */
534 	struct mmc *mmc;
535 
536 	/* DT should have been read & host config filled in */
537 	host = &mmc_host[dev_index];
538 	if (!host->enabled)
539 		return -1;
540 
541 	debug(" do_mmc_init: index %d, bus width %d "
542 		"pwr_gpio %d cd_gpio %d\n",
543 		dev_index, host->width,
544 		host->pwr_gpio.gpio, host->cd_gpio.gpio);
545 
546 	host->clock = 0;
547 	clock_start_periph_pll(host->mmc_id, CLOCK_ID_PERIPH, 20000000);
548 
549 	if (fdt_gpio_isvalid(&host->pwr_gpio)) {
550 		sprintf(gpusage, "SD/MMC%d PWR", dev_index);
551 		gpio_request(host->pwr_gpio.gpio, gpusage);
552 		gpio_direction_output(host->pwr_gpio.gpio, 1);
553 		debug(" Power GPIO name = %s\n", host->pwr_gpio.name);
554 	}
555 
556 	if (fdt_gpio_isvalid(&host->cd_gpio)) {
557 		sprintf(gpusage, "SD/MMC%d CD", dev_index);
558 		gpio_request(host->cd_gpio.gpio, gpusage);
559 		gpio_direction_input(host->cd_gpio.gpio);
560 		debug(" CD GPIO name = %s\n", host->cd_gpio.name);
561 	}
562 
563 	memset(&host->cfg, 0, sizeof(host->cfg));
564 
565 	host->cfg.name = "Tegra SD/MMC";
566 	host->cfg.ops = &tegra_mmc_ops;
567 
568 	host->cfg.voltages = MMC_VDD_32_33 | MMC_VDD_33_34 | MMC_VDD_165_195;
569 	host->cfg.host_caps = 0;
570 	if (host->width == 8)
571 		host->cfg.host_caps |= MMC_MODE_8BIT;
572 	if (host->width >= 4)
573 		host->cfg.host_caps |= MMC_MODE_4BIT;
574 	host->cfg.host_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS | MMC_MODE_HC;
575 
576 	/*
577 	 * min freq is for card identification, and is the highest
578 	 *  low-speed SDIO card frequency (actually 400KHz)
579 	 * max freq is highest HS eMMC clock as per the SD/MMC spec
580 	 *  (actually 52MHz)
581 	 */
582 	host->cfg.f_min = 375000;
583 	host->cfg.f_max = 48000000;
584 
585 	host->cfg.b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
586 
587 	mmc = mmc_create(&host->cfg, host);
588 	if (mmc == NULL)
589 		return -1;
590 
591 	return 0;
592 }
593 
594 /**
595  * Get the host address and peripheral ID for a node.
596  *
597  * @param blob		fdt blob
598  * @param node		Device index (0-3)
599  * @param host		Structure to fill in (reg, width, mmc_id)
600  */
601 static int mmc_get_config(const void *blob, int node, struct mmc_host *host)
602 {
603 	debug("%s: node = %d\n", __func__, node);
604 
605 	host->enabled = fdtdec_get_is_enabled(blob, node);
606 
607 	host->reg = (struct tegra_mmc *)fdtdec_get_addr(blob, node, "reg");
608 	if ((fdt_addr_t)host->reg == FDT_ADDR_T_NONE) {
609 		debug("%s: no sdmmc base reg info found\n", __func__);
610 		return -FDT_ERR_NOTFOUND;
611 	}
612 
613 	host->mmc_id = clock_decode_periph_id(blob, node);
614 	if (host->mmc_id == PERIPH_ID_NONE) {
615 		debug("%s: could not decode periph id\n", __func__);
616 		return -FDT_ERR_NOTFOUND;
617 	}
618 
619 	/*
620 	 * NOTE: mmc->bus_width is determined by mmc.c dynamically.
621 	 * TBD: Override it with this value?
622 	 */
623 	host->width = fdtdec_get_int(blob, node, "bus-width", 0);
624 	if (!host->width)
625 		debug("%s: no sdmmc width found\n", __func__);
626 
627 	/* These GPIOs are optional */
628 	fdtdec_decode_gpio(blob, node, "cd-gpios", &host->cd_gpio);
629 	fdtdec_decode_gpio(blob, node, "wp-gpios", &host->wp_gpio);
630 	fdtdec_decode_gpio(blob, node, "power-gpios", &host->pwr_gpio);
631 
632 	debug("%s: found controller at %p, width = %d, periph_id = %d\n",
633 		__func__, host->reg, host->width, host->mmc_id);
634 	return 0;
635 }
636 
637 /*
638  * Process a list of nodes, adding them to our list of SDMMC ports.
639  *
640  * @param blob          fdt blob
641  * @param node_list     list of nodes to process (any <=0 are ignored)
642  * @param count         number of nodes to process
643  * @return 0 if ok, -1 on error
644  */
645 static int process_nodes(const void *blob, int node_list[], int count)
646 {
647 	struct mmc_host *host;
648 	int i, node;
649 
650 	debug("%s: count = %d\n", __func__, count);
651 
652 	/* build mmc_host[] for each controller */
653 	for (i = 0; i < count; i++) {
654 		node = node_list[i];
655 		if (node <= 0)
656 			continue;
657 
658 		host = &mmc_host[i];
659 		host->id = i;
660 
661 		if (mmc_get_config(blob, node, host)) {
662 			printf("%s: failed to decode dev %d\n",	__func__, i);
663 			return -1;
664 		}
665 		do_mmc_init(i);
666 	}
667 	return 0;
668 }
669 
670 void tegra_mmc_init(void)
671 {
672 	int node_list[MAX_HOSTS], count;
673 	const void *blob = gd->fdt_blob;
674 	debug("%s entry\n", __func__);
675 
676 	/* See if any Tegra124 MMC controllers are present */
677 	count = fdtdec_find_aliases_for_id(blob, "sdhci",
678 		COMPAT_NVIDIA_TEGRA124_SDMMC, node_list, MAX_HOSTS);
679 	debug("%s: count of Tegra124 sdhci nodes is %d\n", __func__, count);
680 	if (process_nodes(blob, node_list, count)) {
681 		printf("%s: Error processing T30 mmc node(s)!\n", __func__);
682 		return;
683 	}
684 
685 	/* See if any Tegra30 MMC controllers are present */
686 	count = fdtdec_find_aliases_for_id(blob, "sdhci",
687 		COMPAT_NVIDIA_TEGRA30_SDMMC, node_list, MAX_HOSTS);
688 	debug("%s: count of T30 sdhci nodes is %d\n", __func__, count);
689 	if (process_nodes(blob, node_list, count)) {
690 		printf("%s: Error processing T30 mmc node(s)!\n", __func__);
691 		return;
692 	}
693 
694 	/* Now look for any Tegra20 MMC controllers */
695 	count = fdtdec_find_aliases_for_id(blob, "sdhci",
696 		COMPAT_NVIDIA_TEGRA20_SDMMC, node_list, MAX_HOSTS);
697 	debug("%s: count of T20 sdhci nodes is %d\n", __func__, count);
698 	if (process_nodes(blob, node_list, count)) {
699 		printf("%s: Error processing T20 mmc node(s)!\n", __func__);
700 		return;
701 	}
702 }
703