mmc.c

/*
 * Copyright 2008, Freescale Semiconductor, Inc
 * Andy Fleming
 *
 * Based vaguely on the Linux code
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <config.h>
#include <common.h>
#include <command.h>
#include <mmc.h>
#include <part.h>
#include <malloc.h>
#include <linux/list.h>
#include <div64.h>

/* Set block count limit because of 16 bit register limit on some hardware*/
#ifndef CONFIG_SYS_MMC_MAX_BLK_COUNT
#define CONFIG_SYS_MMC_MAX_BLK_COUNT 65535
#endif

static struct list_head mmc_devices;
static int cur_dev_num = -1;

int __weak board_mmc_getwp(struct mmc *mmc)
{
	return -1;
}

int mmc_getwp(struct mmc *mmc)
{
	int wp;

	wp = board_mmc_getwp(mmc);

	if (wp < 0) {
		if (mmc->getwp)
			wp = mmc->getwp(mmc);
		else
			wp = 0;
	}

	return wp;
}

int __board_mmc_getcd(struct mmc *mmc) {
	return -1;
}

int board_mmc_getcd(struct mmc *mmc)__attribute__((weak,
	alias("__board_mmc_getcd")));

static int mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
			struct mmc_data *data)
{
	int ret;

#ifdef CONFIG_MMC_TRACE
	int i;
	u8 *ptr;

	printf("CMD_SEND:%d\n", cmd->cmdidx);
	printf("\t\tARG\t\t\t 0x%08X\n", cmd->cmdarg);
	ret = mmc->send_cmd(mmc, cmd, data);
	switch (cmd->resp_type) {
		case MMC_RSP_NONE:
			printf("\t\tMMC_RSP_NONE\n");
			break;
		case MMC_RSP_R1:
			printf("\t\tMMC_RSP_R1,5,6,7 \t 0x%08X \n",
				cmd->response[0]);
			break;
		case MMC_RSP_R1b:
			printf("\t\tMMC_RSP_R1b\t\t 0x%08X \n",
				cmd->response[0]);
			break;
		case MMC_RSP_R2:
			printf("\t\tMMC_RSP_R2\t\t 0x%08X \n",
				cmd->response[0]);
			printf("\t\t          \t\t 0x%08X \n",
				cmd->response[1]);
			printf("\t\t          \t\t 0x%08X \n",
				cmd->response[2]);
			printf("\t\t          \t\t 0x%08X \n",
				cmd->response[3]);
			printf("\n");
			printf("\t\t\t\t\tDUMPING DATA\n");
			for (i = 0; i < 4; i++) {
				int j;
				printf("\t\t\t\t\t%03d - ", i*4);
				ptr = (u8 *)&cmd->response[i];
				ptr += 3;
				for (j = 0; j < 4; j++)
					printf("%02X ", *ptr--);
				printf("\n");
			}
			break;
		case MMC_RSP_R3:
			printf("\t\tMMC_RSP_R3,4\t\t 0x%08X \n",
				cmd->response[0]);
			break;
		default:
			printf("\t\tERROR MMC rsp not supported\n");
			break;
	}
#else
	ret = mmc->send_cmd(mmc, cmd, data);
#endif
	return ret;
}

static int mmc_send_status(struct mmc *mmc, int timeout)
{
	struct mmc_cmd cmd;
	int err, retries = 5;
#ifdef CONFIG_MMC_TRACE
	int status;
#endif

	cmd.cmdidx = MMC_CMD_SEND_STATUS;
	cmd.resp_type = MMC_RSP_R1;
	if (!mmc_host_is_spi(mmc))
		cmd.cmdarg = mmc->rca << 16;

	do {
		err = mmc_send_cmd(mmc, &cmd, NULL);
		if (!err) {
			if ((cmd.response[0] & MMC_STATUS_RDY_FOR_DATA) &&
			    (cmd.response[0] & MMC_STATUS_CURR_STATE) !=
			     MMC_STATE_PRG)
				break;
			else if (cmd.response[0] & MMC_STATUS_MASK) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
				printf("Status Error: 0x%08X\n",
					cmd.response[0]);
#endif
				return COMM_ERR;
			}
		} else if (--retries < 0)
			return err;

		udelay(1000);

	} while (timeout--);

#ifdef CONFIG_MMC_TRACE
	status = (cmd.response[0] & MMC_STATUS_CURR_STATE) >> 9;
	printf("CURR STATE:%d\n", status);
#endif
	if (timeout <= 0) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
		printf("Timeout waiting card ready\n");
#endif
		return TIMEOUT;
	}

	return 0;
}

static int mmc_set_blocklen(struct mmc *mmc, int len)
{
	struct mmc_cmd cmd;

	cmd.cmdidx = MMC_CMD_SET_BLOCKLEN;
	cmd.resp_type = MMC_RSP_R1;
	cmd.cmdarg = len;

	return mmc_send_cmd(mmc, &cmd, NULL);
}

struct mmc *find_mmc_device(int dev_num)
{
	struct mmc *m;
	struct list_head *entry;

	list_for_each(entry, &mmc_devices) {
		m = list_entry(entry, struct mmc, link);

		if (m->block_dev.dev == dev_num)
			return m;
	}

#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
	printf("MMC Device %d not found\n", dev_num);
#endif

	return NULL;
}

static ulong mmc_erase_t(struct mmc *mmc, ulong start, lbaint_t blkcnt)
{
	struct mmc_cmd cmd;
	ulong end;
	int err, start_cmd, end_cmd;

	if (mmc->high_capacity)
		end = start + blkcnt - 1;
	else {
		end = (start + blkcnt - 1) * mmc->write_bl_len;
		start *= mmc->write_bl_len;
	}

	if (IS_SD(mmc)) {
		start_cmd = SD_CMD_ERASE_WR_BLK_START;
		end_cmd = SD_CMD_ERASE_WR_BLK_END;
	} else {
		start_cmd = MMC_CMD_ERASE_GROUP_START;
		end_cmd = MMC_CMD_ERASE_GROUP_END;
	}

	cmd.cmdidx = start_cmd;
	cmd.cmdarg = start;
	cmd.resp_type = MMC_RSP_R1;

	err = mmc_send_cmd(mmc, &cmd, NULL);
	if (err)
		goto err_out;

	cmd.cmdidx = end_cmd;
	cmd.cmdarg = end;

	err = mmc_send_cmd(mmc, &cmd, NULL);
	if (err)
		goto err_out;

	cmd.cmdidx = MMC_CMD_ERASE;
	cmd.cmdarg = SECURE_ERASE;
	cmd.resp_type = MMC_RSP_R1b;

	err = mmc_send_cmd(mmc, &cmd, NULL);
	if (err)
		goto err_out;

	return 0;

err_out:
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
	puts("mmc erase failed\n");
#endif
	return err;
}

static unsigned long
mmc_berase(int dev_num, lbaint_t start, lbaint_t blkcnt)
{
	int err = 0;
	struct mmc *mmc = find_mmc_device(dev_num);
	lbaint_t blk = 0, blk_r = 0;
	int timeout = 1000;

	if (!mmc)
		return -1;

#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
	if ((start % mmc->erase_grp_size) || (blkcnt % mmc->erase_grp_size))
		printf("\n\nCaution! Your devices Erase group is 0x%x\n"
		       "The erase range would be change to "
		       "0x" LBAF "~0x" LBAF "\n\n",
		       mmc->erase_grp_size, start & ~(mmc->erase_grp_size - 1),
		       ((start + blkcnt + mmc->erase_grp_size)
		       & ~(mmc->erase_grp_size - 1)) - 1);
#endif

	while (blk < blkcnt) {
		blk_r = ((blkcnt - blk) > mmc->erase_grp_size) ?
			mmc->erase_grp_size : (blkcnt - blk);
		err = mmc_erase_t(mmc, start + blk, blk_r);
		if (err)
			break;

		blk += blk_r;

		/* Waiting for the ready status */
		if (mmc_send_status(mmc, timeout))
			return 0;
	}

	return blk;
}

static ulong
mmc_write_blocks(struct mmc *mmc, lbaint_t start, lbaint_t blkcnt, const void*src)
{
	struct mmc_cmd cmd;
	struct mmc_data data;
	int timeout = 1000;

	if ((start + blkcnt) > mmc->block_dev.lba) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
		printf("MMC: block number 0x" LBAF " exceeds max(0x" LBAF ")\n",
			start + blkcnt, mmc->block_dev.lba);
#endif
		return 0;
	}

	if (blkcnt == 0)
		return 0;
	else if (blkcnt == 1)
		cmd.cmdidx = MMC_CMD_WRITE_SINGLE_BLOCK;
	else
		cmd.cmdidx = MMC_CMD_WRITE_MULTIPLE_BLOCK;

	if (mmc->high_capacity)
		cmd.cmdarg = start;
	else
		cmd.cmdarg = start * mmc->write_bl_len;

	cmd.resp_type = MMC_RSP_R1;

	data.src = src;
	data.blocks = blkcnt;
	data.blocksize = mmc->write_bl_len;
	data.flags = MMC_DATA_WRITE;

	if (mmc_send_cmd(mmc, &cmd, &data)) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
		printf("mmc write failed\n");
#endif
		return 0;
	}

	/* SPI multiblock writes terminate using a special
	 * token, not a STOP_TRANSMISSION request.
	 */
	if (!mmc_host_is_spi(mmc) && blkcnt > 1) {
		cmd.cmdidx = MMC_CMD_STOP_TRANSMISSION;
		cmd.cmdarg = 0;
		cmd.resp_type = MMC_RSP_R1b;
		if (mmc_send_cmd(mmc, &cmd, NULL)) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
			printf("mmc fail to send stop cmd\n");
#endif
			return 0;
		}
	}

	/* Waiting for the ready status */
	if (mmc_send_status(mmc, timeout))
		return 0;

	return blkcnt;
}

static ulong
mmc_bwrite(int dev_num, lbaint_t start, lbaint_t blkcnt, const void*src)
{
	lbaint_t cur, blocks_todo = blkcnt;

	struct mmc *mmc = find_mmc_device(dev_num);
	if (!mmc)
		return 0;

	if (mmc_set_blocklen(mmc, mmc->write_bl_len))
		return 0;

	do {
		cur = (blocks_todo > mmc->b_max) ?  mmc->b_max : blocks_todo;
		if(mmc_write_blocks(mmc, start, cur, src) != cur)
			return 0;
		blocks_todo -= cur;
		start += cur;
		src += cur * mmc->write_bl_len;
	} while (blocks_todo > 0);

	return blkcnt;
}

static int mmc_read_blocks(struct mmc *mmc, void *dst, lbaint_t start,
			   lbaint_t blkcnt)
{
	struct mmc_cmd cmd;
	struct mmc_data data;

	if (blkcnt > 1)
		cmd.cmdidx = MMC_CMD_READ_MULTIPLE_BLOCK;
	else
		cmd.cmdidx = MMC_CMD_READ_SINGLE_BLOCK;

	if (mmc->high_capacity)
		cmd.cmdarg = start;
	else
		cmd.cmdarg = start * mmc->read_bl_len;

	cmd.resp_type = MMC_RSP_R1;

	data.dest = dst;
	data.blocks = blkcnt;
	data.blocksize = mmc->read_bl_len;
	data.flags = MMC_DATA_READ;

	if (mmc_send_cmd(mmc, &cmd, &data))
		return 0;

	if (blkcnt > 1) {
		cmd.cmdidx = MMC_CMD_STOP_TRANSMISSION;
		cmd.cmdarg = 0;
		cmd.resp_type = MMC_RSP_R1b;
		if (mmc_send_cmd(mmc, &cmd, NULL)) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
			printf("mmc fail to send stop cmd\n");
#endif
			return 0;
		}
	}

	return blkcnt;
}

static ulong mmc_bread(int dev_num, lbaint_t start, lbaint_t blkcnt, void *dst)
{
	lbaint_t cur, blocks_todo = blkcnt;

	if (blkcnt == 0)
		return 0;

	struct mmc *mmc = find_mmc_device(dev_num);
	if (!mmc)
		return 0;

	if ((start + blkcnt) > mmc->block_dev.lba) {
#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_LIBCOMMON_SUPPORT)
		printf("MMC: block number 0x" LBAF " exceeds max(0x" LBAF ")\n",
			start + blkcnt, mmc->block_dev.lba);
#endif
		return 0;
	}

	if (mmc_set_blocklen(mmc, mmc->read_bl_len))
		return 0;

	do {
		cur = (blocks_todo > mmc->b_max) ?  mmc->b_max : blocks_todo;
		if(mmc_read_blocks(mmc, dst, start, cur) != cur)
			return 0;
		blocks_todo -= cur;
		start += cur;
		dst += cur * mmc->read_bl_len;
	} while (blocks_todo > 0);

	return blkcnt;
}

static int mmc_go_idle(struct mmc *mmc)
{
	struct mmc_cmd cmd;
	int err;

	udelay(1000);

	cmd.cmdidx = MMC_CMD_GO_IDLE_STATE;
	cmd.cmdarg = 0;
	cmd.resp_type = MMC_RSP_NONE;

	err = mmc_send_cmd(mmc, &cmd, NULL);

	if (err)
		return err;

	udelay(2000);

	return 0;
}

static int sd_send_op_cond(struct mmc *mmc)
{
	int timeout = 1000;
	int err;
	struct mmc_cmd cmd;

	do {
		cmd.cmdidx = MMC_CMD_APP_CMD;
		cmd.resp_type = MMC_RSP_R1;
		cmd.cmdarg = 0;

		err = mmc_send_cmd(mmc, &cmd, NULL);

		if (err)
			return err;

		cmd.cmdidx = SD_CMD_APP_SEND_OP_COND;
		cmd.resp_type = MMC_RSP_R3;

		/*
		 * Most cards do not answer if some reserved bits
		 * in the ocr are set. However, Some controller
		 * can set bit 7 (reserved for low voltages), but
		 * how to manage low voltages SD card is not yet
		 * specified.
		 */
		cmd.cmdarg = mmc_host_is_spi(mmc) ? 0 :
			(mmc->voltages & 0xff8000);

		if (mmc->version == SD_VERSION_2)
			cmd.cmdarg |= OCR_HCS;

		err = mmc_send_cmd(mmc, &cmd, NULL);

		if (err)
			return err;

		udelay(1000);
	} while ((!(cmd.response[0] & OCR_BUSY)) && timeout--);

	if (timeout <= 0)
		return UNUSABLE_ERR;

	if (mmc->version != SD_VERSION_2)
		mmc->version = SD_VERSION_1_0;

	if (mmc_host_is_spi(mmc)) { /* read OCR for spi */
		cmd.cmdidx = MMC_CMD_SPI_READ_OCR;
		cmd.resp_type = MMC_RSP_R3;
		cmd.cmdarg = 0;

		err = mmc_send_cmd(mmc, &cmd, NULL);

		if (err)
			return err;
	}

	mmc->ocr = cmd.response[0];

	mmc->high_capacity = ((mmc->ocr & OCR_HCS) == OCR_HCS);
	mmc->rca = 0;

	return 0;
}

/* We pass in the cmd since otherwise the init seems to fail */
static int mmc_send_op_cond_iter(struct mmc *mmc, struct mmc_cmd *cmd,
		int use_arg)
{
	int err;

	cmd->cmdidx = MMC_CMD_SEND_OP_COND;
	cmd->resp_type = MMC_RSP_R3;
	cmd->cmdarg = 0;
	if (use_arg && !mmc_host_is_spi(mmc)) {
		cmd->cmdarg =
			(mmc->voltages &
			(mmc->op_cond_response & OCR_VOLTAGE_MASK)) |
			(mmc->op_cond_response & OCR_ACCESS_MODE);

		if (mmc->host_caps & MMC_MODE_HC)
			cmd->cmdarg |= OCR_HCS;
	}
	err = mmc_send_cmd(mmc, cmd, NULL);
	if (err)
		return err;
	mmc->op_cond_response = cmd->response[0];
	return 0;
}

int mmc_send_op_cond(struct mmc *mmc)
{
	struct mmc_cmd cmd;
	int err, i;

	/* Some cards seem to need this */
	mmc_go_idle(mmc);

 	/* Asking to the card its capabilities */
	mmc->op_cond_pending = 1;
	for (i = 0; i < 2; i++) {
		err = mmc_send_op_cond_iter(mmc, &cmd, i != 0);
		if (err)
			return err;

		/* exit if not busy (flag seems to be inverted) */
		if (mmc->op_cond_response & OCR_BUSY)
			return 0;
	}
	return IN_PROGRESS;
}

int mmc_complete_op_cond(struct mmc *mmc)
{
	struct mmc_cmd cmd;
	int timeout = 1000;
	uint start;
	int err;

	mmc->op_cond_pending = 0;
	start = get_timer(0);
	do {
		err = mmc_send_op_cond_iter(mmc, &cmd, 1);
		if (err)
			return err;
		if (get_timer(start) > timeout)
			return UNUSABLE_ERR;
		udelay(100);
	} while (!(mmc->op_cond_response & OCR_BUSY));

	if (mmc_host_is_spi(mmc)) { /* read OCR for spi */
		cmd.cmdidx = MMC_CMD_SPI_READ_OCR;
		cmd.resp_type = MMC_RSP_R3;
		cmd.cmdarg = 0;

		err = mmc_send_cmd(mmc, &cmd, NULL);

		if (err)
			return err;
	}

	mmc->version = MMC_VERSION_UNKNOWN;
	mmc->ocr = cmd.response[0];

	mmc->high_capacity = ((mmc->ocr & OCR_HCS) == OCR_HCS);
	mmc->rca = 0;

	return 0;
}


static int mmc_send_ext_csd(struct mmc *mmc, u8 *ext_csd)
{
	struct mmc_cmd cmd;
	struct mmc_data data;
	int err;

	/* Get the Card Status Register */
	cmd.cmdidx = MMC_CMD_SEND_EXT_CSD;
	cmd.resp_type = MMC_RSP_R1;
	cmd.cmdarg = 0;

	data.dest = (char *)ext_csd;
	data.blocks = 1;
	data.blocksize = MMC_MAX_BLOCK_LEN;
	data.flags = MMC_DATA_READ;

	err = mmc_send_cmd(mmc, &cmd, &data);

	return err;
}


static int mmc_switch(struct mmc *mmc, u8 set, u8 index, u8 value)
{
	struct mmc_cmd cmd;
	int timeout = 1000;
	int ret;

	cmd.cmdidx = MMC_CMD_SWITCH;
	cmd.resp_type = MMC_RSP_R1b;
	cmd.cmdarg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
				 (index << 16) |
				 (value << 8);

	ret = mmc_send_cmd(mmc, &cmd, NULL);

	/* Waiting for the ready status */
	if (!ret)
		ret = mmc_send_status(mmc, timeout);

	return ret;

}

static int mmc_change_freq(struct mmc *mmc)
{
	ALLOC_CACHE_ALIGN_BUFFER(u8, ext_csd, MMC_MAX_BLOCK_LEN);
	char cardtype;
	int err;

	mmc->card_caps = 0;

	if (mmc_host_is_spi(mmc))
		return 0;

	/* Only version 4 supports high-speed */
	if (mmc->version < MMC_VERSION_4)
		return 0;

	err = mmc_send_ext_csd(mmc, ext_csd);

	if (err)
		return err;

	cardtype = ext_csd[EXT_CSD_CARD_TYPE] & 0xf;

	err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING, 1);

	if (err)
		return err;

	/* Now check to see that it worked */
	err = mmc_send_ext_csd(mmc, ext_csd);

	if (err)
		return err;

	/* No high-speed support */
	if (!ext_csd[EXT_CSD_HS_TIMING])
		return 0;

	/* High Speed is set, there are two types: 52MHz and 26MHz */
	if (cardtype & MMC_HS_52MHZ)
		mmc->card_caps |= MMC_MODE_HS_52MHz | MMC_MODE_HS;
	else
		mmc->card_caps |= MMC_MODE_HS;

	return 0;
}

static int mmc_set_capacity(struct mmc *mmc, int part_num)
{
	switch (part_num) {
	case 0:
		mmc->capacity = mmc->capacity_user;
		break;
	case 1:
	case 2:
		mmc->capacity = mmc->capacity_boot;
		break;
	case 3:
		mmc->capacity = mmc->capacity_rpmb;
		break;
	case 4:
	case 5:
	case 6:
	case 7:
		mmc->capacity = mmc->capacity_gp[part_num - 4];
		break;
	default:
		return -1;
	}

	mmc->block_dev.lba = lldiv(mmc->capacity, mmc->read_bl_len);

	return 0;
}

int mmc_switch_part(int dev_num, unsigned int part_num)
{
	struct mmc *mmc = find_mmc_device(dev_num);
	int ret;

	if (!mmc)
		return -1;

	ret = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_PART_CONF,
			 (mmc->part_config & ~PART_ACCESS_MASK)
			 | (part_num & PART_ACCESS_MASK));
	if (ret)
		return ret;

	return mmc_set_capacity(mmc, part_num);
}

int mmc_getcd(struct mmc *mmc)
{
	int cd;

	cd = board_mmc_getcd(mmc);

	if (cd < 0) {
		if (mmc->getcd)
			cd = mmc->getcd(mmc);
		else
			cd = 1;
	}

	return cd;
}

static int sd_switch(struct mmc *mmc, int mode, int group, u8 value, u8 *resp)
{
	struct mmc_cmd cmd;
	struct mmc_data data;

	/* Switch the frequency */
	cmd.cmdidx = SD_CMD_SWITCH_FUNC;
	cmd.resp_type = MMC_RSP_R1;
	cmd.cmdarg = (mode << 31) | 0xffffff;
	cmd.cmdarg &= ~(0xf << (group * 4));
	cmd.cmdarg |= value << (group * 4);

	data.dest = (char *)resp;
	data.blocksize = 64;
	data.blocks = 1;
	data.flags = MMC_DATA_READ;

	return mmc_send_cmd(mmc, &cmd, &data);
}


static int sd_change_freq(struct mmc *mmc)
{
	int err;
	struct mmc_cmd cmd;
	ALLOC_CACHE_ALIGN_BUFFER(uint, scr, 2);
	ALLOC_CACHE_ALIGN_BUFFER(uint, switch_status, 16);
	struct mmc_data data;
	int timeout;

	mmc->card_caps = 0;

	if (mmc_host_is_spi(mmc))
		return 0;

	/* Read the SCR to find out if this card supports higher speeds */
	cmd.cmdidx = MMC_CMD_APP_CMD;
	cmd.resp_type = MMC_RSP_R1;
	cmd.cmdarg = mmc->rca << 16;

	err = mmc_send_cmd(mmc, &cmd, NULL);

	if (err)
		return err;

	cmd.cmdidx = SD_CMD_APP_SEND_SCR;
	cmd.resp_type = MMC_RSP_R1;
	cmd.cmdarg = 0;

	timeout = 3;

retry_scr:
	data.dest = (char *)scr;
	data.blocksize = 8;
	data.blocks = 1;
	data.flags = MMC_DATA_READ;

	err = mmc_send_cmd(mmc, &cmd, &data);

	if (err) {
		if (timeout--)
			goto retry_scr;

		return err;
	}

	mmc->scr[0] = __be32_to_cpu(scr[0]);
	mmc->scr[1] = __be32_to_cpu(scr[1]);

	switch ((mmc->scr[0] >> 24) & 0xf) {
		case 0:
			mmc->version = SD_VERSION_1_0;
			break;
		case 1:
			mmc->version = SD_VERSION_1_10;
			break;
		case 2:
			mmc->version = SD_VERSION_2;
			if ((mmc->scr[0] >> 15) & 0x1)
				mmc->version = SD_VERSION_3;
			break;
		default:
			mmc->version = SD_VERSION_1_0;
			break;
	}

	if (mmc->scr[0] & SD_DATA_4BIT)
		mmc->card_caps |= MMC_MODE_4BIT;

	/* Version 1.0 doesn't support switching */
	if (mmc->version == SD_VERSION_1_0)
		return 0;

	timeout = 4;
	while (timeout--) {
		err = sd_switch(mmc, SD_SWITCH_CHECK, 0, 1,
				(u8 *)switch_status);

		if (err)
			return err;

		/* The high-speed function is busy.  Try again */
		if (!(__be32_to_cpu(switch_status[7]) & SD_HIGHSPEED_BUSY))
			break;
	}

	/* If high-speed isn't supported, we return */
	if (!(__be32_to_cpu(switch_status[3]) & SD_HIGHSPEED_SUPPORTED))
		return 0;

	/*
	 * If the host doesn't support SD_HIGHSPEED, do not switch card to
	 * HIGHSPEED mode even if the card support SD_HIGHSPPED.
	 * This can avoid furthur problem when the card runs in different
	 * mode between the host.
	 */
	if (!((mmc->host_caps & MMC_MODE_HS_52MHz) &&
		(mmc->host_caps & MMC_MODE_HS)))
		return 0;

	err = sd_switch(mmc, SD_SWITCH_SWITCH, 0, 1, (u8 *)switch_status);

	if (err)
		return err;

	if ((__be32_to_cpu(switch_status[4]) & 0x0f000000) == 0x01000000)
		mmc->card_caps |= MMC_MODE_HS;

	return 0;
}

/* frequency bases */
/* divided by 10 to be nice to platforms without floating point */
static const int fbase[] = {
	10000,
	100000,
	1000000,
	10000000,
};

/* Multiplier values for TRAN_SPEED.  Multiplied by 10 to be nice
 * to platforms without floating point.
 */
static const int multipliers[] = {
	0,	/* reserved */
	10,
	12,
	13,
	15,
	20,
	25,
	30,
	35,
	40,
	45,
	50,
	55,
	60,
	70,
	80,
};

static void mmc_set_ios(struct mmc *mmc)
{
	mmc->set_ios(mmc);
}

void mmc_set_clock(struct mmc *mmc, uint clock)
{
	if (clock > mmc->f_max)
		clock = mmc->f_max;

	if (clock < mmc->f_min)
		clock = mmc->f_min;

	mmc->clock = clock;

	mmc_set_ios(mmc);
}

static void mmc_set_bus_width(struct mmc *mmc, uint width)
{
	mmc->bus_width = width;

	mmc_set_ios(mmc);
}

static int mmc_startup(struct mmc *mmc)
{
	int err, i;
	uint mult, freq;
	u64 cmult, csize, capacity;
	struct mmc_cmd cmd;
	ALLOC_CACHE_ALIGN_BUFFER(u8, ext_csd, MMC_MAX_BLOCK_LEN);
	ALLOC_CACHE_ALIGN_BUFFER(u8, test_csd, MMC_MAX_BLOCK_LEN);
	int timeout = 1000;

#ifdef CONFIG_MMC_SPI_CRC_ON
	if (mmc_host_is_spi(mmc)) { /* enable CRC check for spi */
		cmd.cmdidx = MMC_CMD_SPI_CRC_ON_OFF;
		cmd.resp_type = MMC_RSP_R1;
		cmd.cmdarg = 1;
		err = mmc_send_cmd(mmc, &cmd, NULL);

		if (err)
			return err;
	}
#endif

	/* Put the Card in Identify Mode */
	cmd.cmdidx = mmc_host_is_spi(mmc) ? MMC_CMD_SEND_CID :
		MMC_CMD_ALL_SEND_CID; /* cmd not supported in spi */
	cmd.resp_type = MMC_RSP_R2;
	cmd.cmdarg = 0;

	err = mmc_send_cmd(mmc, &cmd, NULL);

	if (err)
		return err;

	memcpy(mmc->cid, cmd.response, 16);

	/*
	 * For MMC cards, set the Relative Address.
	 * For SD cards, get the Relatvie Address.
	 * This also puts the cards into Standby State
	 */
	if (!mmc_host_is_spi(mmc)) { /* cmd not supported in spi */
		cmd.cmdidx = SD_CMD_SEND_RELATIVE_ADDR;
		cmd.cmdarg = mmc->rca << 16;
		cmd.resp_type = MMC_RSP_R6;

		err = mmc_send_cmd(mmc, &cmd, NULL);