xref: /openbmc/linux/drivers/mmc/core/sd.c (revision f220d3eb)
1 /*
2  *  linux/drivers/mmc/core/sd.c
3  *
4  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
5  *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
6  *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/err.h>
14 #include <linux/sizes.h>
15 #include <linux/slab.h>
16 #include <linux/stat.h>
17 #include <linux/pm_runtime.h>
18 
19 #include <linux/mmc/host.h>
20 #include <linux/mmc/card.h>
21 #include <linux/mmc/mmc.h>
22 #include <linux/mmc/sd.h>
23 
24 #include "core.h"
25 #include "card.h"
26 #include "host.h"
27 #include "bus.h"
28 #include "mmc_ops.h"
29 #include "sd.h"
30 #include "sd_ops.h"
31 
32 static const unsigned int tran_exp[] = {
33 	10000,		100000,		1000000,	10000000,
34 	0,		0,		0,		0
35 };
36 
37 static const unsigned char tran_mant[] = {
38 	0,	10,	12,	13,	15,	20,	25,	30,
39 	35,	40,	45,	50,	55,	60,	70,	80,
40 };
41 
42 static const unsigned int taac_exp[] = {
43 	1,	10,	100,	1000,	10000,	100000,	1000000, 10000000,
44 };
45 
46 static const unsigned int taac_mant[] = {
47 	0,	10,	12,	13,	15,	20,	25,	30,
48 	35,	40,	45,	50,	55,	60,	70,	80,
49 };
50 
51 static const unsigned int sd_au_size[] = {
52 	0,		SZ_16K / 512,		SZ_32K / 512,	SZ_64K / 512,
53 	SZ_128K / 512,	SZ_256K / 512,		SZ_512K / 512,	SZ_1M / 512,
54 	SZ_2M / 512,	SZ_4M / 512,		SZ_8M / 512,	(SZ_8M + SZ_4M) / 512,
55 	SZ_16M / 512,	(SZ_16M + SZ_8M) / 512,	SZ_32M / 512,	SZ_64M / 512,
56 };
57 
58 #define UNSTUFF_BITS(resp,start,size)					\
59 	({								\
60 		const int __size = size;				\
61 		const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1;	\
62 		const int __off = 3 - ((start) / 32);			\
63 		const int __shft = (start) & 31;			\
64 		u32 __res;						\
65 									\
66 		__res = resp[__off] >> __shft;				\
67 		if (__size + __shft > 32)				\
68 			__res |= resp[__off-1] << ((32 - __shft) % 32);	\
69 		__res & __mask;						\
70 	})
71 
72 /*
73  * Given the decoded CSD structure, decode the raw CID to our CID structure.
74  */
75 void mmc_decode_cid(struct mmc_card *card)
76 {
77 	u32 *resp = card->raw_cid;
78 
79 	/*
80 	 * SD doesn't currently have a version field so we will
81 	 * have to assume we can parse this.
82 	 */
83 	card->cid.manfid		= UNSTUFF_BITS(resp, 120, 8);
84 	card->cid.oemid			= UNSTUFF_BITS(resp, 104, 16);
85 	card->cid.prod_name[0]		= UNSTUFF_BITS(resp, 96, 8);
86 	card->cid.prod_name[1]		= UNSTUFF_BITS(resp, 88, 8);
87 	card->cid.prod_name[2]		= UNSTUFF_BITS(resp, 80, 8);
88 	card->cid.prod_name[3]		= UNSTUFF_BITS(resp, 72, 8);
89 	card->cid.prod_name[4]		= UNSTUFF_BITS(resp, 64, 8);
90 	card->cid.hwrev			= UNSTUFF_BITS(resp, 60, 4);
91 	card->cid.fwrev			= UNSTUFF_BITS(resp, 56, 4);
92 	card->cid.serial		= UNSTUFF_BITS(resp, 24, 32);
93 	card->cid.year			= UNSTUFF_BITS(resp, 12, 8);
94 	card->cid.month			= UNSTUFF_BITS(resp, 8, 4);
95 
96 	card->cid.year += 2000; /* SD cards year offset */
97 }
98 
99 /*
100  * Given a 128-bit response, decode to our card CSD structure.
101  */
102 static int mmc_decode_csd(struct mmc_card *card)
103 {
104 	struct mmc_csd *csd = &card->csd;
105 	unsigned int e, m, csd_struct;
106 	u32 *resp = card->raw_csd;
107 
108 	csd_struct = UNSTUFF_BITS(resp, 126, 2);
109 
110 	switch (csd_struct) {
111 	case 0:
112 		m = UNSTUFF_BITS(resp, 115, 4);
113 		e = UNSTUFF_BITS(resp, 112, 3);
114 		csd->taac_ns	 = (taac_exp[e] * taac_mant[m] + 9) / 10;
115 		csd->taac_clks	 = UNSTUFF_BITS(resp, 104, 8) * 100;
116 
117 		m = UNSTUFF_BITS(resp, 99, 4);
118 		e = UNSTUFF_BITS(resp, 96, 3);
119 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
120 		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
121 
122 		e = UNSTUFF_BITS(resp, 47, 3);
123 		m = UNSTUFF_BITS(resp, 62, 12);
124 		csd->capacity	  = (1 + m) << (e + 2);
125 
126 		csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
127 		csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
128 		csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
129 		csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
130 		csd->dsr_imp = UNSTUFF_BITS(resp, 76, 1);
131 		csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
132 		csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
133 		csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
134 
135 		if (UNSTUFF_BITS(resp, 46, 1)) {
136 			csd->erase_size = 1;
137 		} else if (csd->write_blkbits >= 9) {
138 			csd->erase_size = UNSTUFF_BITS(resp, 39, 7) + 1;
139 			csd->erase_size <<= csd->write_blkbits - 9;
140 		}
141 		break;
142 	case 1:
143 		/*
144 		 * This is a block-addressed SDHC or SDXC card. Most
145 		 * interesting fields are unused and have fixed
146 		 * values. To avoid getting tripped by buggy cards,
147 		 * we assume those fixed values ourselves.
148 		 */
149 		mmc_card_set_blockaddr(card);
150 
151 		csd->taac_ns	 = 0; /* Unused */
152 		csd->taac_clks	 = 0; /* Unused */
153 
154 		m = UNSTUFF_BITS(resp, 99, 4);
155 		e = UNSTUFF_BITS(resp, 96, 3);
156 		csd->max_dtr	  = tran_exp[e] * tran_mant[m];
157 		csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
158 		csd->c_size	  = UNSTUFF_BITS(resp, 48, 22);
159 
160 		/* SDXC cards have a minimum C_SIZE of 0x00FFFF */
161 		if (csd->c_size >= 0xFFFF)
162 			mmc_card_set_ext_capacity(card);
163 
164 		m = UNSTUFF_BITS(resp, 48, 22);
165 		csd->capacity     = (1 + m) << 10;
166 
167 		csd->read_blkbits = 9;
168 		csd->read_partial = 0;
169 		csd->write_misalign = 0;
170 		csd->read_misalign = 0;
171 		csd->r2w_factor = 4; /* Unused */
172 		csd->write_blkbits = 9;
173 		csd->write_partial = 0;
174 		csd->erase_size = 1;
175 		break;
176 	default:
177 		pr_err("%s: unrecognised CSD structure version %d\n",
178 			mmc_hostname(card->host), csd_struct);
179 		return -EINVAL;
180 	}
181 
182 	card->erase_size = csd->erase_size;
183 
184 	return 0;
185 }
186 
187 /*
188  * Given a 64-bit response, decode to our card SCR structure.
189  */
190 static int mmc_decode_scr(struct mmc_card *card)
191 {
192 	struct sd_scr *scr = &card->scr;
193 	unsigned int scr_struct;
194 	u32 resp[4];
195 
196 	resp[3] = card->raw_scr[1];
197 	resp[2] = card->raw_scr[0];
198 
199 	scr_struct = UNSTUFF_BITS(resp, 60, 4);
200 	if (scr_struct != 0) {
201 		pr_err("%s: unrecognised SCR structure version %d\n",
202 			mmc_hostname(card->host), scr_struct);
203 		return -EINVAL;
204 	}
205 
206 	scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
207 	scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
208 	if (scr->sda_vsn == SCR_SPEC_VER_2)
209 		/* Check if Physical Layer Spec v3.0 is supported */
210 		scr->sda_spec3 = UNSTUFF_BITS(resp, 47, 1);
211 
212 	if (UNSTUFF_BITS(resp, 55, 1))
213 		card->erased_byte = 0xFF;
214 	else
215 		card->erased_byte = 0x0;
216 
217 	if (scr->sda_spec3)
218 		scr->cmds = UNSTUFF_BITS(resp, 32, 2);
219 	return 0;
220 }
221 
222 /*
223  * Fetch and process SD Status register.
224  */
225 static int mmc_read_ssr(struct mmc_card *card)
226 {
227 	unsigned int au, es, et, eo;
228 	__be32 *raw_ssr;
229 	int i;
230 
231 	if (!(card->csd.cmdclass & CCC_APP_SPEC)) {
232 		pr_warn("%s: card lacks mandatory SD Status function\n",
233 			mmc_hostname(card->host));
234 		return 0;
235 	}
236 
237 	raw_ssr = kmalloc(sizeof(card->raw_ssr), GFP_KERNEL);
238 	if (!raw_ssr)
239 		return -ENOMEM;
240 
241 	if (mmc_app_sd_status(card, raw_ssr)) {
242 		pr_warn("%s: problem reading SD Status register\n",
243 			mmc_hostname(card->host));
244 		kfree(raw_ssr);
245 		return 0;
246 	}
247 
248 	for (i = 0; i < 16; i++)
249 		card->raw_ssr[i] = be32_to_cpu(raw_ssr[i]);
250 
251 	kfree(raw_ssr);
252 
253 	/*
254 	 * UNSTUFF_BITS only works with four u32s so we have to offset the
255 	 * bitfield positions accordingly.
256 	 */
257 	au = UNSTUFF_BITS(card->raw_ssr, 428 - 384, 4);
258 	if (au) {
259 		if (au <= 9 || card->scr.sda_spec3) {
260 			card->ssr.au = sd_au_size[au];
261 			es = UNSTUFF_BITS(card->raw_ssr, 408 - 384, 16);
262 			et = UNSTUFF_BITS(card->raw_ssr, 402 - 384, 6);
263 			if (es && et) {
264 				eo = UNSTUFF_BITS(card->raw_ssr, 400 - 384, 2);
265 				card->ssr.erase_timeout = (et * 1000) / es;
266 				card->ssr.erase_offset = eo * 1000;
267 			}
268 		} else {
269 			pr_warn("%s: SD Status: Invalid Allocation Unit size\n",
270 				mmc_hostname(card->host));
271 		}
272 	}
273 
274 	return 0;
275 }
276 
277 /*
278  * Fetches and decodes switch information
279  */
280 static int mmc_read_switch(struct mmc_card *card)
281 {
282 	int err;
283 	u8 *status;
284 
285 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
286 		return 0;
287 
288 	if (!(card->csd.cmdclass & CCC_SWITCH)) {
289 		pr_warn("%s: card lacks mandatory switch function, performance might suffer\n",
290 			mmc_hostname(card->host));
291 		return 0;
292 	}
293 
294 	status = kmalloc(64, GFP_KERNEL);
295 	if (!status)
296 		return -ENOMEM;
297 
298 	/*
299 	 * Find out the card's support bits with a mode 0 operation.
300 	 * The argument does not matter, as the support bits do not
301 	 * change with the arguments.
302 	 */
303 	err = mmc_sd_switch(card, 0, 0, 0, status);
304 	if (err) {
305 		/*
306 		 * If the host or the card can't do the switch,
307 		 * fail more gracefully.
308 		 */
309 		if (err != -EINVAL && err != -ENOSYS && err != -EFAULT)
310 			goto out;
311 
312 		pr_warn("%s: problem reading Bus Speed modes\n",
313 			mmc_hostname(card->host));
314 		err = 0;
315 
316 		goto out;
317 	}
318 
319 	if (status[13] & SD_MODE_HIGH_SPEED)
320 		card->sw_caps.hs_max_dtr = HIGH_SPEED_MAX_DTR;
321 
322 	if (card->scr.sda_spec3) {
323 		card->sw_caps.sd3_bus_mode = status[13];
324 		/* Driver Strengths supported by the card */
325 		card->sw_caps.sd3_drv_type = status[9];
326 		card->sw_caps.sd3_curr_limit = status[7] | status[6] << 8;
327 	}
328 
329 out:
330 	kfree(status);
331 
332 	return err;
333 }
334 
335 /*
336  * Test if the card supports high-speed mode and, if so, switch to it.
337  */
338 int mmc_sd_switch_hs(struct mmc_card *card)
339 {
340 	int err;
341 	u8 *status;
342 
343 	if (card->scr.sda_vsn < SCR_SPEC_VER_1)
344 		return 0;
345 
346 	if (!(card->csd.cmdclass & CCC_SWITCH))
347 		return 0;
348 
349 	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
350 		return 0;
351 
352 	if (card->sw_caps.hs_max_dtr == 0)
353 		return 0;
354 
355 	status = kmalloc(64, GFP_KERNEL);
356 	if (!status)
357 		return -ENOMEM;
358 
359 	err = mmc_sd_switch(card, 1, 0, 1, status);
360 	if (err)
361 		goto out;
362 
363 	if ((status[16] & 0xF) != 1) {
364 		pr_warn("%s: Problem switching card into high-speed mode!\n",
365 			mmc_hostname(card->host));
366 		err = 0;
367 	} else {
368 		err = 1;
369 	}
370 
371 out:
372 	kfree(status);
373 
374 	return err;
375 }
376 
377 static int sd_select_driver_type(struct mmc_card *card, u8 *status)
378 {
379 	int card_drv_type, drive_strength, drv_type;
380 	int err;
381 
382 	card->drive_strength = 0;
383 
384 	card_drv_type = card->sw_caps.sd3_drv_type | SD_DRIVER_TYPE_B;
385 
386 	drive_strength = mmc_select_drive_strength(card,
387 						   card->sw_caps.uhs_max_dtr,
388 						   card_drv_type, &drv_type);
389 
390 	if (drive_strength) {
391 		err = mmc_sd_switch(card, 1, 2, drive_strength, status);
392 		if (err)
393 			return err;
394 		if ((status[15] & 0xF) != drive_strength) {
395 			pr_warn("%s: Problem setting drive strength!\n",
396 				mmc_hostname(card->host));
397 			return 0;
398 		}
399 		card->drive_strength = drive_strength;
400 	}
401 
402 	if (drv_type)
403 		mmc_set_driver_type(card->host, drv_type);
404 
405 	return 0;
406 }
407 
408 static void sd_update_bus_speed_mode(struct mmc_card *card)
409 {
410 	/*
411 	 * If the host doesn't support any of the UHS-I modes, fallback on
412 	 * default speed.
413 	 */
414 	if (!mmc_host_uhs(card->host)) {
415 		card->sd_bus_speed = 0;
416 		return;
417 	}
418 
419 	if ((card->host->caps & MMC_CAP_UHS_SDR104) &&
420 	    (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR104)) {
421 			card->sd_bus_speed = UHS_SDR104_BUS_SPEED;
422 	} else if ((card->host->caps & MMC_CAP_UHS_DDR50) &&
423 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_DDR50)) {
424 			card->sd_bus_speed = UHS_DDR50_BUS_SPEED;
425 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
426 		    MMC_CAP_UHS_SDR50)) && (card->sw_caps.sd3_bus_mode &
427 		    SD_MODE_UHS_SDR50)) {
428 			card->sd_bus_speed = UHS_SDR50_BUS_SPEED;
429 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
430 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25)) &&
431 		   (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR25)) {
432 			card->sd_bus_speed = UHS_SDR25_BUS_SPEED;
433 	} else if ((card->host->caps & (MMC_CAP_UHS_SDR104 |
434 		    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25 |
435 		    MMC_CAP_UHS_SDR12)) && (card->sw_caps.sd3_bus_mode &
436 		    SD_MODE_UHS_SDR12)) {
437 			card->sd_bus_speed = UHS_SDR12_BUS_SPEED;
438 	}
439 }
440 
441 static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status)
442 {
443 	int err;
444 	unsigned int timing = 0;
445 
446 	switch (card->sd_bus_speed) {
447 	case UHS_SDR104_BUS_SPEED:
448 		timing = MMC_TIMING_UHS_SDR104;
449 		card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR;
450 		break;
451 	case UHS_DDR50_BUS_SPEED:
452 		timing = MMC_TIMING_UHS_DDR50;
453 		card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR;
454 		break;
455 	case UHS_SDR50_BUS_SPEED:
456 		timing = MMC_TIMING_UHS_SDR50;
457 		card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR;
458 		break;
459 	case UHS_SDR25_BUS_SPEED:
460 		timing = MMC_TIMING_UHS_SDR25;
461 		card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR;
462 		break;
463 	case UHS_SDR12_BUS_SPEED:
464 		timing = MMC_TIMING_UHS_SDR12;
465 		card->sw_caps.uhs_max_dtr = UHS_SDR12_MAX_DTR;
466 		break;
467 	default:
468 		return 0;
469 	}
470 
471 	err = mmc_sd_switch(card, 1, 0, card->sd_bus_speed, status);
472 	if (err)
473 		return err;
474 
475 	if ((status[16] & 0xF) != card->sd_bus_speed)
476 		pr_warn("%s: Problem setting bus speed mode!\n",
477 			mmc_hostname(card->host));
478 	else {
479 		mmc_set_timing(card->host, timing);
480 		mmc_set_clock(card->host, card->sw_caps.uhs_max_dtr);
481 	}
482 
483 	return 0;
484 }
485 
486 /* Get host's max current setting at its current voltage */
487 static u32 sd_get_host_max_current(struct mmc_host *host)
488 {
489 	u32 voltage, max_current;
490 
491 	voltage = 1 << host->ios.vdd;
492 	switch (voltage) {
493 	case MMC_VDD_165_195:
494 		max_current = host->max_current_180;
495 		break;
496 	case MMC_VDD_29_30:
497 	case MMC_VDD_30_31:
498 		max_current = host->max_current_300;
499 		break;
500 	case MMC_VDD_32_33:
501 	case MMC_VDD_33_34:
502 		max_current = host->max_current_330;
503 		break;
504 	default:
505 		max_current = 0;
506 	}
507 
508 	return max_current;
509 }
510 
511 static int sd_set_current_limit(struct mmc_card *card, u8 *status)
512 {
513 	int current_limit = SD_SET_CURRENT_NO_CHANGE;
514 	int err;
515 	u32 max_current;
516 
517 	/*
518 	 * Current limit switch is only defined for SDR50, SDR104, and DDR50
519 	 * bus speed modes. For other bus speed modes, we do not change the
520 	 * current limit.
521 	 */
522 	if ((card->sd_bus_speed != UHS_SDR50_BUS_SPEED) &&
523 	    (card->sd_bus_speed != UHS_SDR104_BUS_SPEED) &&
524 	    (card->sd_bus_speed != UHS_DDR50_BUS_SPEED))
525 		return 0;
526 
527 	/*
528 	 * Host has different current capabilities when operating at
529 	 * different voltages, so find out its max current first.
530 	 */
531 	max_current = sd_get_host_max_current(card->host);
532 
533 	/*
534 	 * We only check host's capability here, if we set a limit that is
535 	 * higher than the card's maximum current, the card will be using its
536 	 * maximum current, e.g. if the card's maximum current is 300ma, and
537 	 * when we set current limit to 200ma, the card will draw 200ma, and
538 	 * when we set current limit to 400/600/800ma, the card will draw its
539 	 * maximum 300ma from the host.
540 	 *
541 	 * The above is incorrect: if we try to set a current limit that is
542 	 * not supported by the card, the card can rightfully error out the
543 	 * attempt, and remain at the default current limit.  This results
544 	 * in a 300mA card being limited to 200mA even though the host
545 	 * supports 800mA. Failures seen with SanDisk 8GB UHS cards with
546 	 * an iMX6 host. --rmk
547 	 */
548 	if (max_current >= 800 &&
549 	    card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_800)
550 		current_limit = SD_SET_CURRENT_LIMIT_800;
551 	else if (max_current >= 600 &&
552 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_600)
553 		current_limit = SD_SET_CURRENT_LIMIT_600;
554 	else if (max_current >= 400 &&
555 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_400)
556 		current_limit = SD_SET_CURRENT_LIMIT_400;
557 	else if (max_current >= 200 &&
558 		 card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_200)
559 		current_limit = SD_SET_CURRENT_LIMIT_200;
560 
561 	if (current_limit != SD_SET_CURRENT_NO_CHANGE) {
562 		err = mmc_sd_switch(card, 1, 3, current_limit, status);
563 		if (err)
564 			return err;
565 
566 		if (((status[15] >> 4) & 0x0F) != current_limit)
567 			pr_warn("%s: Problem setting current limit!\n",
568 				mmc_hostname(card->host));
569 
570 	}
571 
572 	return 0;
573 }
574 
575 /*
576  * UHS-I specific initialization procedure
577  */
578 static int mmc_sd_init_uhs_card(struct mmc_card *card)
579 {
580 	int err;
581 	u8 *status;
582 
583 	if (!(card->csd.cmdclass & CCC_SWITCH))
584 		return 0;
585 
586 	status = kmalloc(64, GFP_KERNEL);
587 	if (!status)
588 		return -ENOMEM;
589 
590 	/* Set 4-bit bus width */
591 	err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
592 	if (err)
593 		goto out;
594 
595 	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
596 
597 	/*
598 	 * Select the bus speed mode depending on host
599 	 * and card capability.
600 	 */
601 	sd_update_bus_speed_mode(card);
602 
603 	/* Set the driver strength for the card */
604 	err = sd_select_driver_type(card, status);
605 	if (err)
606 		goto out;
607 
608 	/* Set current limit for the card */
609 	err = sd_set_current_limit(card, status);
610 	if (err)
611 		goto out;
612 
613 	/* Set bus speed mode of the card */
614 	err = sd_set_bus_speed_mode(card, status);
615 	if (err)
616 		goto out;
617 
618 	/*
619 	 * SPI mode doesn't define CMD19 and tuning is only valid for SDR50 and
620 	 * SDR104 mode SD-cards. Note that tuning is mandatory for SDR104.
621 	 */
622 	if (!mmc_host_is_spi(card->host) &&
623 		(card->host->ios.timing == MMC_TIMING_UHS_SDR50 ||
624 		 card->host->ios.timing == MMC_TIMING_UHS_DDR50 ||
625 		 card->host->ios.timing == MMC_TIMING_UHS_SDR104)) {
626 		err = mmc_execute_tuning(card);
627 
628 		/*
629 		 * As SD Specifications Part1 Physical Layer Specification
630 		 * Version 3.01 says, CMD19 tuning is available for unlocked
631 		 * cards in transfer state of 1.8V signaling mode. The small
632 		 * difference between v3.00 and 3.01 spec means that CMD19
633 		 * tuning is also available for DDR50 mode.
634 		 */
635 		if (err && card->host->ios.timing == MMC_TIMING_UHS_DDR50) {
636 			pr_warn("%s: ddr50 tuning failed\n",
637 				mmc_hostname(card->host));
638 			err = 0;
639 		}
640 	}
641 
642 out:
643 	kfree(status);
644 
645 	return err;
646 }
647 
648 MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
649 	card->raw_cid[2], card->raw_cid[3]);
650 MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
651 	card->raw_csd[2], card->raw_csd[3]);
652 MMC_DEV_ATTR(scr, "%08x%08x\n", card->raw_scr[0], card->raw_scr[1]);
653 MMC_DEV_ATTR(ssr,
654 	"%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x\n",
655 		card->raw_ssr[0], card->raw_ssr[1], card->raw_ssr[2],
656 		card->raw_ssr[3], card->raw_ssr[4], card->raw_ssr[5],
657 		card->raw_ssr[6], card->raw_ssr[7], card->raw_ssr[8],
658 		card->raw_ssr[9], card->raw_ssr[10], card->raw_ssr[11],
659 		card->raw_ssr[12], card->raw_ssr[13], card->raw_ssr[14],
660 		card->raw_ssr[15]);
661 MMC_DEV_ATTR(date, "%02d/%04d\n", card->cid.month, card->cid.year);
662 MMC_DEV_ATTR(erase_size, "%u\n", card->erase_size << 9);
663 MMC_DEV_ATTR(preferred_erase_size, "%u\n", card->pref_erase << 9);
664 MMC_DEV_ATTR(fwrev, "0x%x\n", card->cid.fwrev);
665 MMC_DEV_ATTR(hwrev, "0x%x\n", card->cid.hwrev);
666 MMC_DEV_ATTR(manfid, "0x%06x\n", card->cid.manfid);
667 MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
668 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
669 MMC_DEV_ATTR(serial, "0x%08x\n", card->cid.serial);
670 MMC_DEV_ATTR(ocr, "0x%08x\n", card->ocr);
671 MMC_DEV_ATTR(rca, "0x%04x\n", card->rca);
672 
673 
674 static ssize_t mmc_dsr_show(struct device *dev,
675                            struct device_attribute *attr,
676                            char *buf)
677 {
678        struct mmc_card *card = mmc_dev_to_card(dev);
679        struct mmc_host *host = card->host;
680 
681        if (card->csd.dsr_imp && host->dsr_req)
682                return sprintf(buf, "0x%x\n", host->dsr);
683        else
684                /* return default DSR value */
685                return sprintf(buf, "0x%x\n", 0x404);
686 }
687 
688 static DEVICE_ATTR(dsr, S_IRUGO, mmc_dsr_show, NULL);
689 
690 static struct attribute *sd_std_attrs[] = {
691 	&dev_attr_cid.attr,
692 	&dev_attr_csd.attr,
693 	&dev_attr_scr.attr,
694 	&dev_attr_ssr.attr,
695 	&dev_attr_date.attr,
696 	&dev_attr_erase_size.attr,
697 	&dev_attr_preferred_erase_size.attr,
698 	&dev_attr_fwrev.attr,
699 	&dev_attr_hwrev.attr,
700 	&dev_attr_manfid.attr,
701 	&dev_attr_name.attr,
702 	&dev_attr_oemid.attr,
703 	&dev_attr_serial.attr,
704 	&dev_attr_ocr.attr,
705 	&dev_attr_rca.attr,
706 	&dev_attr_dsr.attr,
707 	NULL,
708 };
709 ATTRIBUTE_GROUPS(sd_std);
710 
711 struct device_type sd_type = {
712 	.groups = sd_std_groups,
713 };
714 
715 /*
716  * Fetch CID from card.
717  */
718 int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr)
719 {
720 	int err;
721 	u32 max_current;
722 	int retries = 10;
723 	u32 pocr = ocr;
724 
725 try_again:
726 	if (!retries) {
727 		ocr &= ~SD_OCR_S18R;
728 		pr_warn("%s: Skipping voltage switch\n", mmc_hostname(host));
729 	}
730 
731 	/*
732 	 * Since we're changing the OCR value, we seem to
733 	 * need to tell some cards to go back to the idle
734 	 * state.  We wait 1ms to give cards time to
735 	 * respond.
736 	 */
737 	mmc_go_idle(host);
738 
739 	/*
740 	 * If SD_SEND_IF_COND indicates an SD 2.0
741 	 * compliant card and we should set bit 30
742 	 * of the ocr to indicate that we can handle
743 	 * block-addressed SDHC cards.
744 	 */
745 	err = mmc_send_if_cond(host, ocr);
746 	if (!err)
747 		ocr |= SD_OCR_CCS;
748 
749 	/*
750 	 * If the host supports one of UHS-I modes, request the card
751 	 * to switch to 1.8V signaling level. If the card has failed
752 	 * repeatedly to switch however, skip this.
753 	 */
754 	if (retries && mmc_host_uhs(host))
755 		ocr |= SD_OCR_S18R;
756 
757 	/*
758 	 * If the host can supply more than 150mA at current voltage,
759 	 * XPC should be set to 1.
760 	 */
761 	max_current = sd_get_host_max_current(host);
762 	if (max_current > 150)
763 		ocr |= SD_OCR_XPC;
764 
765 	err = mmc_send_app_op_cond(host, ocr, rocr);
766 	if (err)
767 		return err;
768 
769 	/*
770 	 * In case CCS and S18A in the response is set, start Signal Voltage
771 	 * Switch procedure. SPI mode doesn't support CMD11.
772 	 */
773 	if (!mmc_host_is_spi(host) && rocr &&
774 	   ((*rocr & 0x41000000) == 0x41000000)) {
775 		err = mmc_set_uhs_voltage(host, pocr);
776 		if (err == -EAGAIN) {
777 			retries--;
778 			goto try_again;
779 		} else if (err) {
780 			retries = 0;
781 			goto try_again;
782 		}
783 	}
784 
785 	err = mmc_send_cid(host, cid);
786 	return err;
787 }
788 
789 int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card)
790 {
791 	int err;
792 
793 	/*
794 	 * Fetch CSD from card.
795 	 */
796 	err = mmc_send_csd(card, card->raw_csd);
797 	if (err)
798 		return err;
799 
800 	err = mmc_decode_csd(card);
801 	if (err)
802 		return err;
803 
804 	return 0;
805 }
806 
807 static int mmc_sd_get_ro(struct mmc_host *host)
808 {
809 	int ro;
810 
811 	/*
812 	 * Some systems don't feature a write-protect pin and don't need one.
813 	 * E.g. because they only have micro-SD card slot. For those systems
814 	 * assume that the SD card is always read-write.
815 	 */
816 	if (host->caps2 & MMC_CAP2_NO_WRITE_PROTECT)
817 		return 0;
818 
819 	if (!host->ops->get_ro)
820 		return -1;
821 
822 	ro = host->ops->get_ro(host);
823 
824 	return ro;
825 }
826 
827 int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
828 	bool reinit)
829 {
830 	int err;
831 
832 	if (!reinit) {
833 		/*
834 		 * Fetch SCR from card.
835 		 */
836 		err = mmc_app_send_scr(card);
837 		if (err)
838 			return err;
839 
840 		err = mmc_decode_scr(card);
841 		if (err)
842 			return err;
843 
844 		/*
845 		 * Fetch and process SD Status register.
846 		 */
847 		err = mmc_read_ssr(card);
848 		if (err)
849 			return err;
850 
851 		/* Erase init depends on CSD and SSR */
852 		mmc_init_erase(card);
853 
854 		/*
855 		 * Fetch switch information from card.
856 		 */
857 		err = mmc_read_switch(card);
858 		if (err)
859 			return err;
860 	}
861 
862 	/*
863 	 * For SPI, enable CRC as appropriate.
864 	 * This CRC enable is located AFTER the reading of the
865 	 * card registers because some SDHC cards are not able
866 	 * to provide valid CRCs for non-512-byte blocks.
867 	 */
868 	if (mmc_host_is_spi(host)) {
869 		err = mmc_spi_set_crc(host, use_spi_crc);
870 		if (err)
871 			return err;
872 	}
873 
874 	/*
875 	 * Check if read-only switch is active.
876 	 */
877 	if (!reinit) {
878 		int ro = mmc_sd_get_ro(host);
879 
880 		if (ro < 0) {
881 			pr_warn("%s: host does not support reading read-only switch, assuming write-enable\n",
882 				mmc_hostname(host));
883 		} else if (ro > 0) {
884 			mmc_card_set_readonly(card);
885 		}
886 	}
887 
888 	return 0;
889 }
890 
891 unsigned mmc_sd_get_max_clock(struct mmc_card *card)
892 {
893 	unsigned max_dtr = (unsigned int)-1;
894 
895 	if (mmc_card_hs(card)) {
896 		if (max_dtr > card->sw_caps.hs_max_dtr)
897 			max_dtr = card->sw_caps.hs_max_dtr;
898 	} else if (max_dtr > card->csd.max_dtr) {
899 		max_dtr = card->csd.max_dtr;
900 	}
901 
902 	return max_dtr;
903 }
904 
905 static bool mmc_sd_card_using_v18(struct mmc_card *card)
906 {
907 	/*
908 	 * According to the SD spec., the Bus Speed Mode (function group 1) bits
909 	 * 2 to 4 are zero if the card is initialized at 3.3V signal level. Thus
910 	 * they can be used to determine if the card has already switched to
911 	 * 1.8V signaling.
912 	 */
913 	return card->sw_caps.sd3_bus_mode &
914 	       (SD_MODE_UHS_SDR50 | SD_MODE_UHS_SDR104 | SD_MODE_UHS_DDR50);
915 }
916 
917 /*
918  * Handle the detection and initialisation of a card.
919  *
920  * In the case of a resume, "oldcard" will contain the card
921  * we're trying to reinitialise.
922  */
923 static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
924 	struct mmc_card *oldcard)
925 {
926 	struct mmc_card *card;
927 	int err;
928 	u32 cid[4];
929 	u32 rocr = 0;
930 	bool v18_fixup_failed = false;
931 
932 	WARN_ON(!host->claimed);
933 retry:
934 	err = mmc_sd_get_cid(host, ocr, cid, &rocr);
935 	if (err)
936 		return err;
937 
938 	if (oldcard) {
939 		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
940 			return -ENOENT;
941 
942 		card = oldcard;
943 	} else {
944 		/*
945 		 * Allocate card structure.
946 		 */
947 		card = mmc_alloc_card(host, &sd_type);
948 		if (IS_ERR(card))
949 			return PTR_ERR(card);
950 
951 		card->ocr = ocr;
952 		card->type = MMC_TYPE_SD;
953 		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
954 	}
955 
956 	/*
957 	 * Call the optional HC's init_card function to handle quirks.
958 	 */
959 	if (host->ops->init_card)
960 		host->ops->init_card(host, card);
961 
962 	/*
963 	 * For native busses:  get card RCA and quit open drain mode.
964 	 */
965 	if (!mmc_host_is_spi(host)) {
966 		err = mmc_send_relative_addr(host, &card->rca);
967 		if (err)
968 			goto free_card;
969 	}
970 
971 	if (!oldcard) {
972 		err = mmc_sd_get_csd(host, card);
973 		if (err)
974 			goto free_card;
975 
976 		mmc_decode_cid(card);
977 	}
978 
979 	/*
980 	 * handling only for cards supporting DSR and hosts requesting
981 	 * DSR configuration
982 	 */
983 	if (card->csd.dsr_imp && host->dsr_req)
984 		mmc_set_dsr(host);
985 
986 	/*
987 	 * Select card, as all following commands rely on that.
988 	 */
989 	if (!mmc_host_is_spi(host)) {
990 		err = mmc_select_card(card);
991 		if (err)
992 			goto free_card;
993 	}
994 
995 	err = mmc_sd_setup_card(host, card, oldcard != NULL);
996 	if (err)
997 		goto free_card;
998 
999 	/*
1000 	 * If the card has not been power cycled, it may still be using 1.8V
1001 	 * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
1002 	 * transfer mode.
1003 	 */
1004 	if (!v18_fixup_failed && !mmc_host_is_spi(host) && mmc_host_uhs(host) &&
1005 	    mmc_sd_card_using_v18(card) &&
1006 	    host->ios.signal_voltage != MMC_SIGNAL_VOLTAGE_180) {
1007 		/*
1008 		 * Re-read switch information in case it has changed since
1009 		 * oldcard was initialized.
1010 		 */
1011 		if (oldcard) {
1012 			err = mmc_read_switch(card);
1013 			if (err)
1014 				goto free_card;
1015 		}
1016 		if (mmc_sd_card_using_v18(card)) {
1017 			if (mmc_host_set_uhs_voltage(host) ||
1018 			    mmc_sd_init_uhs_card(card)) {
1019 				v18_fixup_failed = true;
1020 				mmc_power_cycle(host, ocr);
1021 				if (!oldcard)
1022 					mmc_remove_card(card);
1023 				goto retry;
1024 			}
1025 			goto done;
1026 		}
1027 	}
1028 
1029 	/* Initialization sequence for UHS-I cards */
1030 	if (rocr & SD_ROCR_S18A && mmc_host_uhs(host)) {
1031 		err = mmc_sd_init_uhs_card(card);
1032 		if (err)
1033 			goto free_card;
1034 	} else {
1035 		/*
1036 		 * Attempt to change to high-speed (if supported)
1037 		 */
1038 		err = mmc_sd_switch_hs(card);
1039 		if (err > 0)
1040 			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
1041 		else if (err)
1042 			goto free_card;
1043 
1044 		/*
1045 		 * Set bus speed.
1046 		 */
1047 		mmc_set_clock(host, mmc_sd_get_max_clock(card));
1048 
1049 		/*
1050 		 * Switch to wider bus (if supported).
1051 		 */
1052 		if ((host->caps & MMC_CAP_4_BIT_DATA) &&
1053 			(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
1054 			err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
1055 			if (err)
1056 				goto free_card;
1057 
1058 			mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
1059 		}
1060 	}
1061 
1062 	if (host->caps2 & MMC_CAP2_AVOID_3_3V &&
1063 	    host->ios.signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
1064 		pr_err("%s: Host failed to negotiate down from 3.3V\n",
1065 			mmc_hostname(host));
1066 		err = -EINVAL;
1067 		goto free_card;
1068 	}
1069 done:
1070 	host->card = card;
1071 	return 0;
1072 
1073 free_card:
1074 	if (!oldcard)
1075 		mmc_remove_card(card);
1076 
1077 	return err;
1078 }
1079 
1080 /*
1081  * Host is being removed. Free up the current card.
1082  */
1083 static void mmc_sd_remove(struct mmc_host *host)
1084 {
1085 	mmc_remove_card(host->card);
1086 	host->card = NULL;
1087 }
1088 
1089 /*
1090  * Card detection - card is alive.
1091  */
1092 static int mmc_sd_alive(struct mmc_host *host)
1093 {
1094 	return mmc_send_status(host->card, NULL);
1095 }
1096 
1097 /*
1098  * Card detection callback from host.
1099  */
1100 static void mmc_sd_detect(struct mmc_host *host)
1101 {
1102 	int err;
1103 
1104 	mmc_get_card(host->card, NULL);
1105 
1106 	/*
1107 	 * Just check if our card has been removed.
1108 	 */
1109 	err = _mmc_detect_card_removed(host);
1110 
1111 	mmc_put_card(host->card, NULL);
1112 
1113 	if (err) {
1114 		mmc_sd_remove(host);
1115 
1116 		mmc_claim_host(host);
1117 		mmc_detach_bus(host);
1118 		mmc_power_off(host);
1119 		mmc_release_host(host);
1120 	}
1121 }
1122 
1123 static int _mmc_sd_suspend(struct mmc_host *host)
1124 {
1125 	int err = 0;
1126 
1127 	mmc_claim_host(host);
1128 
1129 	if (mmc_card_suspended(host->card))
1130 		goto out;
1131 
1132 	if (!mmc_host_is_spi(host))
1133 		err = mmc_deselect_cards(host);
1134 
1135 	if (!err) {
1136 		mmc_power_off(host);
1137 		mmc_card_set_suspended(host->card);
1138 	}
1139 
1140 out:
1141 	mmc_release_host(host);
1142 	return err;
1143 }
1144 
1145 /*
1146  * Callback for suspend
1147  */
1148 static int mmc_sd_suspend(struct mmc_host *host)
1149 {
1150 	int err;
1151 
1152 	err = _mmc_sd_suspend(host);
1153 	if (!err) {
1154 		pm_runtime_disable(&host->card->dev);
1155 		pm_runtime_set_suspended(&host->card->dev);
1156 	}
1157 
1158 	return err;
1159 }
1160 
1161 /*
1162  * This function tries to determine if the same card is still present
1163  * and, if so, restore all state to it.
1164  */
1165 static int _mmc_sd_resume(struct mmc_host *host)
1166 {
1167 	int err = 0;
1168 
1169 	mmc_claim_host(host);
1170 
1171 	if (!mmc_card_suspended(host->card))
1172 		goto out;
1173 
1174 	mmc_power_up(host, host->card->ocr);
1175 	err = mmc_sd_init_card(host, host->card->ocr, host->card);
1176 	mmc_card_clr_suspended(host->card);
1177 
1178 out:
1179 	mmc_release_host(host);
1180 	return err;
1181 }
1182 
1183 /*
1184  * Callback for resume
1185  */
1186 static int mmc_sd_resume(struct mmc_host *host)
1187 {
1188 	pm_runtime_enable(&host->card->dev);
1189 	return 0;
1190 }
1191 
1192 /*
1193  * Callback for runtime_suspend.
1194  */
1195 static int mmc_sd_runtime_suspend(struct mmc_host *host)
1196 {
1197 	int err;
1198 
1199 	if (!(host->caps & MMC_CAP_AGGRESSIVE_PM))
1200 		return 0;
1201 
1202 	err = _mmc_sd_suspend(host);
1203 	if (err)
1204 		pr_err("%s: error %d doing aggressive suspend\n",
1205 			mmc_hostname(host), err);
1206 
1207 	return err;
1208 }
1209 
1210 /*
1211  * Callback for runtime_resume.
1212  */
1213 static int mmc_sd_runtime_resume(struct mmc_host *host)
1214 {
1215 	int err;
1216 
1217 	err = _mmc_sd_resume(host);
1218 	if (err && err != -ENOMEDIUM)
1219 		pr_err("%s: error %d doing runtime resume\n",
1220 			mmc_hostname(host), err);
1221 
1222 	return 0;
1223 }
1224 
1225 static int mmc_sd_hw_reset(struct mmc_host *host)
1226 {
1227 	mmc_power_cycle(host, host->card->ocr);
1228 	return mmc_sd_init_card(host, host->card->ocr, host->card);
1229 }
1230 
1231 static const struct mmc_bus_ops mmc_sd_ops = {
1232 	.remove = mmc_sd_remove,
1233 	.detect = mmc_sd_detect,
1234 	.runtime_suspend = mmc_sd_runtime_suspend,
1235 	.runtime_resume = mmc_sd_runtime_resume,
1236 	.suspend = mmc_sd_suspend,
1237 	.resume = mmc_sd_resume,
1238 	.alive = mmc_sd_alive,
1239 	.shutdown = mmc_sd_suspend,
1240 	.hw_reset = mmc_sd_hw_reset,
1241 };
1242 
1243 /*
1244  * Starting point for SD card init.
1245  */
1246 int mmc_attach_sd(struct mmc_host *host)
1247 {
1248 	int err;
1249 	u32 ocr, rocr;
1250 
1251 	WARN_ON(!host->claimed);
1252 
1253 	err = mmc_send_app_op_cond(host, 0, &ocr);
1254 	if (err)
1255 		return err;
1256 
1257 	mmc_attach_bus(host, &mmc_sd_ops);
1258 	if (host->ocr_avail_sd)
1259 		host->ocr_avail = host->ocr_avail_sd;
1260 
1261 	/*
1262 	 * We need to get OCR a different way for SPI.
1263 	 */
1264 	if (mmc_host_is_spi(host)) {
1265 		mmc_go_idle(host);
1266 
1267 		err = mmc_spi_read_ocr(host, 0, &ocr);
1268 		if (err)
1269 			goto err;
1270 	}
1271 
1272 	rocr = mmc_select_voltage(host, ocr);
1273 
1274 	/*
1275 	 * Can we support the voltage(s) of the card(s)?
1276 	 */
1277 	if (!rocr) {
1278 		err = -EINVAL;
1279 		goto err;
1280 	}
1281 
1282 	/*
1283 	 * Detect and init the card.
1284 	 */
1285 	err = mmc_sd_init_card(host, rocr, NULL);
1286 	if (err)
1287 		goto err;
1288 
1289 	mmc_release_host(host);
1290 	err = mmc_add_card(host->card);
1291 	if (err)
1292 		goto remove_card;
1293 
1294 	mmc_claim_host(host);
1295 	return 0;
1296 
1297 remove_card:
1298 	mmc_remove_card(host->card);
1299 	host->card = NULL;
1300 	mmc_claim_host(host);
1301 err:
1302 	mmc_detach_bus(host);
1303 
1304 	pr_err("%s: error %d whilst initialising SD card\n",
1305 		mmc_hostname(host), err);
1306 
1307 	return err;
1308 }
1309