drivers/mmc/mxsmmc.c - github/trini/u-boot - Gitiles

 /*
  * Freescale i.MX28 SSP MMC driver
  *
  * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
  * on behalf of DENX Software Engineering GmbH
  *
  * Based on code from LTIB:
  * (C) Copyright 2008-2010 Freescale Semiconductor, Inc.
  * Terry Lv
  *
  * Copyright 2007, Freescale Semiconductor, Inc
  * Andy Fleming
  *
  * Based vaguely on the pxa mmc code:
  * (C) Copyright 2003
  * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
  *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of
  * the License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  * MA 02111-1307 USA
  */
 #include <common.h>
 #include <malloc.h>
 #include <mmc.h>
 #include <asm/errno.h>
 #include <asm/io.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/imx-regs.h>
 #include <asm/arch/sys_proto.h>

 struct mxsmmc_priv {
 	int			id;
 	struct mx28_ssp_regs	*regs;
 	uint32_t		clkseq_bypass;
 	uint32_t		*clkctrl_ssp;
 	uint32_t		buswidth;
 	int			(*mmc_is_wp)(int);
 };

 #define	MXSMMC_MAX_TIMEOUT	10000

 /*
  * Sends a command out on the bus.  Takes the mmc pointer,
  * a command pointer, and an optional data pointer.
  */
 static int
 mxsmmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
 {
 	struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
 	struct mx28_ssp_regs *ssp_regs = priv->regs;
 	uint32_t reg;
 	int timeout;
 	uint32_t data_count;
 	uint32_t *data_ptr;
 	uint32_t ctrl0;

 	debug("MMC%d: CMD%d\n", mmc->block_dev.dev, cmd->cmdidx);

 	/* Check bus busy */
 	timeout = MXSMMC_MAX_TIMEOUT;
 	while (--timeout) {
 		udelay(1000);
 		reg = readl(&ssp_regs->hw_ssp_status);
 		if (!(reg &
 			(SSP_STATUS_BUSY | SSP_STATUS_DATA_BUSY |
 			SSP_STATUS_CMD_BUSY))) {
 			break;
 		}
 	}

 	if (!timeout) {
 		printf("MMC%d: Bus busy timeout!\n", mmc->block_dev.dev);
 		return TIMEOUT;
 	}

 	/* See if card is present */
 	if (readl(&ssp_regs->hw_ssp_status) & SSP_STATUS_CARD_DETECT) {
 		printf("MMC%d: No card detected!\n", mmc->block_dev.dev);
 		return NO_CARD_ERR;
 	}

 	/* Start building CTRL0 contents */
 	ctrl0 = priv->buswidth;

 	/* Set up command */
 	if (!(cmd->resp_type & MMC_RSP_CRC))
 		ctrl0 |= SSP_CTRL0_IGNORE_CRC;
 	if (cmd->resp_type & MMC_RSP_PRESENT)	/* Need to get response */
 		ctrl0 |= SSP_CTRL0_GET_RESP;
 	if (cmd->resp_type & MMC_RSP_136)	/* It's a 136 bits response */
 		ctrl0 |= SSP_CTRL0_LONG_RESP;

 	/* Command index */
 	reg = readl(&ssp_regs->hw_ssp_cmd0);
 	reg &= ~(SSP_CMD0_CMD_MASK | SSP_CMD0_APPEND_8CYC);
 	reg |= cmd->cmdidx << SSP_CMD0_CMD_OFFSET;
 	if (cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION)
 		reg |= SSP_CMD0_APPEND_8CYC;
 	writel(reg, &ssp_regs->hw_ssp_cmd0);

 	/* Command argument */
 	writel(cmd->cmdarg, &ssp_regs->hw_ssp_cmd1);

 	/* Set up data */
 	if (data) {
 		/* READ or WRITE */
 		if (data->flags & MMC_DATA_READ) {
 			ctrl0 |= SSP_CTRL0_READ;
 		} else if (priv->mmc_is_wp(mmc->block_dev.dev)) {
 			printf("MMC%d: Can not write a locked card!\n",
 				mmc->block_dev.dev);
 			return UNUSABLE_ERR;
 		}

 		ctrl0 |= SSP_CTRL0_DATA_XFER;
 		reg = ((data->blocks - 1) <<
 			SSP_BLOCK_SIZE_BLOCK_COUNT_OFFSET) |
 			((ffs(data->blocksize) - 1) <<
 			SSP_BLOCK_SIZE_BLOCK_SIZE_OFFSET);
 		writel(reg, &ssp_regs->hw_ssp_block_size);

 		reg = data->blocksize * data->blocks;
 		writel(reg, &ssp_regs->hw_ssp_xfer_size);
 	}

 	/* Kick off the command */
 	ctrl0 |= SSP_CTRL0_WAIT_FOR_IRQ | SSP_CTRL0_ENABLE | SSP_CTRL0_RUN;
 	writel(ctrl0, &ssp_regs->hw_ssp_ctrl0);

 	/* Wait for the command to complete */
 	timeout = MXSMMC_MAX_TIMEOUT;
 	while (--timeout) {
 		udelay(1000);
 		reg = readl(&ssp_regs->hw_ssp_status);
 		if (!(reg & SSP_STATUS_CMD_BUSY))
 			break;
 	}

 	if (!timeout) {
 		printf("MMC%d: Command %d busy\n",
 			mmc->block_dev.dev, cmd->cmdidx);
 		return TIMEOUT;
 	}

 	/* Check command timeout */
 	if (reg & SSP_STATUS_RESP_TIMEOUT) {
 		printf("MMC%d: Command %d timeout (status 0x%08x)\n",
 			mmc->block_dev.dev, cmd->cmdidx, reg);
 		return TIMEOUT;
 	}

 	/* Check command errors */
 	if (reg & (SSP_STATUS_RESP_CRC_ERR | SSP_STATUS_RESP_ERR)) {
 		printf("MMC%d: Command %d error (status 0x%08x)!\n",
 			mmc->block_dev.dev, cmd->cmdidx, reg);
 		return COMM_ERR;
 	}

 	/* Copy response to response buffer */
 	if (cmd->resp_type & MMC_RSP_136) {
 		cmd->response[3] = readl(&ssp_regs->hw_ssp_sdresp0);
 		cmd->response[2] = readl(&ssp_regs->hw_ssp_sdresp1);
 		cmd->response[1] = readl(&ssp_regs->hw_ssp_sdresp2);
 		cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp3);
 	} else
 		cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp0);

 	/* Return if no data to process */
 	if (!data)
 		return 0;

 	/* Process the data */
 	data_count = data->blocksize * data->blocks;
 	timeout = MXSMMC_MAX_TIMEOUT;
 	if (data->flags & MMC_DATA_READ) {
 		data_ptr = (uint32_t *)data->dest;
 		while (data_count && --timeout) {
 			reg = readl(&ssp_regs->hw_ssp_status);
 			if (!(reg & SSP_STATUS_FIFO_EMPTY)) {
 				*data_ptr++ = readl(&ssp_regs->hw_ssp_data);
 				data_count -= 4;
 				timeout = MXSMMC_MAX_TIMEOUT;
 			} else
 				udelay(1000);
 		}
 	} else {
 		data_ptr = (uint32_t *)data->src;
 		timeout *= 100;
 		while (data_count && --timeout) {
 			reg = readl(&ssp_regs->hw_ssp_status);
 			if (!(reg & SSP_STATUS_FIFO_FULL)) {
 				writel(*data_ptr++, &ssp_regs->hw_ssp_data);
 				data_count -= 4;
 				timeout = MXSMMC_MAX_TIMEOUT;
 			} else
 				udelay(1000);
 		}
 	}

 	if (!timeout) {
 		printf("MMC%d: Data timeout with command %d (status 0x%08x)!\n",
 			mmc->block_dev.dev, cmd->cmdidx, reg);
 		return COMM_ERR;
 	}

 	/* Check data errors */
 	reg = readl(&ssp_regs->hw_ssp_status);
 	if (reg &
 		(SSP_STATUS_TIMEOUT | SSP_STATUS_DATA_CRC_ERR |
 		SSP_STATUS_FIFO_OVRFLW | SSP_STATUS_FIFO_UNDRFLW)) {
 		printf("MMC%d: Data error with command %d (status 0x%08x)!\n",
 			mmc->block_dev.dev, cmd->cmdidx, reg);
 		return COMM_ERR;
 	}

 	return 0;
 }

 static void mxsmmc_set_ios(struct mmc *mmc)
 {
 	struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
 	struct mx28_ssp_regs *ssp_regs = priv->regs;

 	/* Set the clock speed */
 	if (mmc->clock)
 		mx28_set_ssp_busclock(priv->id, mmc->clock / 1000);

 	switch (mmc->bus_width) {
 	case 1:
 		priv->buswidth = SSP_CTRL0_BUS_WIDTH_ONE_BIT;
 		break;
 	case 4:
 		priv->buswidth = SSP_CTRL0_BUS_WIDTH_FOUR_BIT;
 		break;
 	case 8:
 		priv->buswidth = SSP_CTRL0_BUS_WIDTH_EIGHT_BIT;
 		break;
 	}

 	/* Set the bus width */
 	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl0,
 			SSP_CTRL0_BUS_WIDTH_MASK, priv->buswidth);

 	debug("MMC%d: Set %d bits bus width\n",
 		mmc->block_dev.dev, mmc->bus_width);
 }

 static int mxsmmc_init(struct mmc *mmc)
 {
 	struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
 	struct mx28_ssp_regs *ssp_regs = priv->regs;

 	/* Reset SSP */
 	mx28_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);

 	/* 8 bits word length in MMC mode */
 	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl1,
 		SSP_CTRL1_SSP_MODE_MASK | SSP_CTRL1_WORD_LENGTH_MASK,
 		SSP_CTRL1_SSP_MODE_SD_MMC | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS);

 	/* Set initial bit clock 400 KHz */
 	mx28_set_ssp_busclock(priv->id, 400);

 	/* Send initial 74 clock cycles (185 us @ 400 KHz)*/
 	writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_set);
 	udelay(200);
 	writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_clr);

 	return 0;
 }

 int mxsmmc_initialize(bd_t *bis, int id, int (*wp)(int))
 {
 	struct mx28_clkctrl_regs *clkctrl_regs =
 		(struct mx28_clkctrl_regs *)MXS_CLKCTRL_BASE;
 	struct mmc *mmc = NULL;
 	struct mxsmmc_priv *priv = NULL;

 	mmc = malloc(sizeof(struct mmc));
 	if (!mmc)
 		return -ENOMEM;

 	priv = malloc(sizeof(struct mxsmmc_priv));
 	if (!priv) {
 		free(mmc);
 		return -ENOMEM;
 	}

 	priv->mmc_is_wp = wp;
 	priv->id = id;
 	switch (id) {
 	case 0:
 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP0_BASE;
 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP0;
 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp0;
 		break;
 	case 1:
 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP1_BASE;
 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP1;
 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp1;
 		break;
 	case 2:
 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP2_BASE;
 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP2;
 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp2;
 		break;
 	case 3:
 		priv->regs = (struct mx28_ssp_regs *)MXS_SSP3_BASE;
 		priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP3;
 		priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp3;
 		break;
 	}

 	sprintf(mmc->name, "MXS MMC");
 	mmc->send_cmd = mxsmmc_send_cmd;
 	mmc->set_ios = mxsmmc_set_ios;
 	mmc->init = mxsmmc_init;
 	mmc->getcd = NULL;
 	mmc->priv = priv;

 	mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;

 	mmc->host_caps = MMC_MODE_4BIT | MMC_MODE_8BIT |
 			 MMC_MODE_HS_52MHz | MMC_MODE_HS;

 	/*
 	 * SSPCLK = 480 * 18 / 29 / 1 = 297.731 MHz
 	 * SSP bit rate = SSPCLK / (CLOCK_DIVIDE * (1 + CLOCK_RATE)),
 	 * CLOCK_DIVIDE has to be an even value from 2 to 254, and
 	 * CLOCK_RATE could be any integer from 0 to 255.
 	 */
 	mmc->f_min = 400000;
 	mmc->f_max = mxc_get_clock(MXC_SSP0_CLK + id) * 1000 / 2;
 	mmc->b_max = 0;

 	mmc_register(mmc);
 	return 0;
 }
	/*
	* Freescale i.MX28 SSP MMC driver
	*
	* Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
	* on behalf of DENX Software Engineering GmbH
	*
	* Based on code from LTIB:
	* (C) Copyright 2008-2010 Freescale Semiconductor, Inc.
	* Terry Lv
	*
	* Copyright 2007, Freescale Semiconductor, Inc
	* Andy Fleming
	*
	* Based vaguely on the pxa mmc code:
	* (C) Copyright 2003
	* Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
	*
	* See file CREDITS for list of people who contributed to this
	* project.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation; either version 2 of
	* the License, or (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	* MA 02111-1307 USA
	*/
	#include <common.h>
	#include <malloc.h>
	#include <mmc.h>
	#include <asm/errno.h>
	#include <asm/io.h>
	#include <asm/arch/clock.h>
	#include <asm/arch/imx-regs.h>
	#include <asm/arch/sys_proto.h>

	struct mxsmmc_priv {
	int id;
	struct mx28_ssp_regs *regs;
	uint32_t clkseq_bypass;
	uint32_t *clkctrl_ssp;
	uint32_t buswidth;
	int (*mmc_is_wp)(int);
	};

	#define MXSMMC_MAX_TIMEOUT 10000

	/*
	* Sends a command out on the bus. Takes the mmc pointer,
	* a command pointer, and an optional data pointer.
	*/
	static int
	mxsmmc_send_cmd(struct mmc mmc, struct mmc_cmd cmd, struct mmc_data *data)
	{
	struct mxsmmc_priv priv = (struct mxsmmc_priv )mmc->priv;
	struct mx28_ssp_regs *ssp_regs = priv->regs;
	uint32_t reg;
	int timeout;
	uint32_t data_count;
	uint32_t *data_ptr;
	uint32_t ctrl0;

	debug("MMC%d: CMD%d\n", mmc->block_dev.dev, cmd->cmdidx);

	/* Check bus busy */
	timeout = MXSMMC_MAX_TIMEOUT;
	while (--timeout) {
	udelay(1000);
	reg = readl(&ssp_regs->hw_ssp_status);
	if (!(reg &
	(SSP_STATUS_BUSY \| SSP_STATUS_DATA_BUSY \|
	SSP_STATUS_CMD_BUSY))) {
	break;
	}
	}

	if (!timeout) {
	printf("MMC%d: Bus busy timeout!\n", mmc->block_dev.dev);
	return TIMEOUT;
	}

	/* See if card is present */
	if (readl(&ssp_regs->hw_ssp_status) & SSP_STATUS_CARD_DETECT) {
	printf("MMC%d: No card detected!\n", mmc->block_dev.dev);
	return NO_CARD_ERR;
	}

	/* Start building CTRL0 contents */
	ctrl0 = priv->buswidth;

	/* Set up command */
	if (!(cmd->resp_type & MMC_RSP_CRC))
	ctrl0 \|= SSP_CTRL0_IGNORE_CRC;
	if (cmd->resp_type & MMC_RSP_PRESENT) /* Need to get response */
	ctrl0 \|= SSP_CTRL0_GET_RESP;
	if (cmd->resp_type & MMC_RSP_136) /* It's a 136 bits response */
	ctrl0 \|= SSP_CTRL0_LONG_RESP;

	/* Command index */
	reg = readl(&ssp_regs->hw_ssp_cmd0);
	reg &= ~(SSP_CMD0_CMD_MASK \| SSP_CMD0_APPEND_8CYC);
	reg \|= cmd->cmdidx << SSP_CMD0_CMD_OFFSET;
	if (cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION)
	reg \|= SSP_CMD0_APPEND_8CYC;
	writel(reg, &ssp_regs->hw_ssp_cmd0);

	/* Command argument */
	writel(cmd->cmdarg, &ssp_regs->hw_ssp_cmd1);

	/* Set up data */
	if (data) {
	/* READ or WRITE */
	if (data->flags & MMC_DATA_READ) {
	ctrl0 \|= SSP_CTRL0_READ;
	} else if (priv->mmc_is_wp(mmc->block_dev.dev)) {
	printf("MMC%d: Can not write a locked card!\n",
	mmc->block_dev.dev);
	return UNUSABLE_ERR;
	}

	ctrl0 \|= SSP_CTRL0_DATA_XFER;
	reg = ((data->blocks - 1) <<
	SSP_BLOCK_SIZE_BLOCK_COUNT_OFFSET) \|
	((ffs(data->blocksize) - 1) <<
	SSP_BLOCK_SIZE_BLOCK_SIZE_OFFSET);
	writel(reg, &ssp_regs->hw_ssp_block_size);

	reg = data->blocksize * data->blocks;
	writel(reg, &ssp_regs->hw_ssp_xfer_size);
	}

	/* Kick off the command */
	ctrl0 \|= SSP_CTRL0_WAIT_FOR_IRQ \| SSP_CTRL0_ENABLE \| SSP_CTRL0_RUN;
	writel(ctrl0, &ssp_regs->hw_ssp_ctrl0);

	/* Wait for the command to complete */
	timeout = MXSMMC_MAX_TIMEOUT;
	while (--timeout) {
	udelay(1000);
	reg = readl(&ssp_regs->hw_ssp_status);
	if (!(reg & SSP_STATUS_CMD_BUSY))
	break;
	}

	if (!timeout) {
	printf("MMC%d: Command %d busy\n",
	mmc->block_dev.dev, cmd->cmdidx);
	return TIMEOUT;
	}

	/* Check command timeout */
	if (reg & SSP_STATUS_RESP_TIMEOUT) {
	printf("MMC%d: Command %d timeout (status 0x%08x)\n",
	mmc->block_dev.dev, cmd->cmdidx, reg);
	return TIMEOUT;
	}

	/* Check command errors */
	if (reg & (SSP_STATUS_RESP_CRC_ERR \| SSP_STATUS_RESP_ERR)) {
	printf("MMC%d: Command %d error (status 0x%08x)!\n",
	mmc->block_dev.dev, cmd->cmdidx, reg);
	return COMM_ERR;
	}

	/* Copy response to response buffer */
	if (cmd->resp_type & MMC_RSP_136) {
	cmd->response[3] = readl(&ssp_regs->hw_ssp_sdresp0);
	cmd->response[2] = readl(&ssp_regs->hw_ssp_sdresp1);
	cmd->response[1] = readl(&ssp_regs->hw_ssp_sdresp2);
	cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp3);
	} else
	cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp0);

	/* Return if no data to process */
	if (!data)
	return 0;

	/* Process the data */
	data_count = data->blocksize * data->blocks;
	timeout = MXSMMC_MAX_TIMEOUT;
	if (data->flags & MMC_DATA_READ) {
	data_ptr = (uint32_t *)data->dest;
	while (data_count && --timeout) {
	reg = readl(&ssp_regs->hw_ssp_status);
	if (!(reg & SSP_STATUS_FIFO_EMPTY)) {
	*data_ptr++ = readl(&ssp_regs->hw_ssp_data);
	data_count -= 4;
	timeout = MXSMMC_MAX_TIMEOUT;
	} else
	udelay(1000);
	}
	} else {
	data_ptr = (uint32_t *)data->src;
	timeout *= 100;
	while (data_count && --timeout) {
	reg = readl(&ssp_regs->hw_ssp_status);
	if (!(reg & SSP_STATUS_FIFO_FULL)) {
	writel(*data_ptr++, &ssp_regs->hw_ssp_data);
	data_count -= 4;
	timeout = MXSMMC_MAX_TIMEOUT;
	} else
	udelay(1000);
	}
	}

	if (!timeout) {
	printf("MMC%d: Data timeout with command %d (status 0x%08x)!\n",
	mmc->block_dev.dev, cmd->cmdidx, reg);
	return COMM_ERR;
	}

	/* Check data errors */
	reg = readl(&ssp_regs->hw_ssp_status);
	if (reg &
	(SSP_STATUS_TIMEOUT \| SSP_STATUS_DATA_CRC_ERR \|
	SSP_STATUS_FIFO_OVRFLW \| SSP_STATUS_FIFO_UNDRFLW)) {
	printf("MMC%d: Data error with command %d (status 0x%08x)!\n",
	mmc->block_dev.dev, cmd->cmdidx, reg);
	return COMM_ERR;
	}

	return 0;
	}

	static void mxsmmc_set_ios(struct mmc *mmc)
	{
	struct mxsmmc_priv priv = (struct mxsmmc_priv )mmc->priv;
	struct mx28_ssp_regs *ssp_regs = priv->regs;

	/* Set the clock speed */
	if (mmc->clock)
	mx28_set_ssp_busclock(priv->id, mmc->clock / 1000);

	switch (mmc->bus_width) {
	case 1:
	priv->buswidth = SSP_CTRL0_BUS_WIDTH_ONE_BIT;
	break;
	case 4:
	priv->buswidth = SSP_CTRL0_BUS_WIDTH_FOUR_BIT;
	break;
	case 8:
	priv->buswidth = SSP_CTRL0_BUS_WIDTH_EIGHT_BIT;
	break;
	}

	/* Set the bus width */
	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl0,
	SSP_CTRL0_BUS_WIDTH_MASK, priv->buswidth);

	debug("MMC%d: Set %d bits bus width\n",
	mmc->block_dev.dev, mmc->bus_width);
	}

	static int mxsmmc_init(struct mmc *mmc)
	{
	struct mxsmmc_priv priv = (struct mxsmmc_priv )mmc->priv;
	struct mx28_ssp_regs *ssp_regs = priv->regs;

	/* Reset SSP */
	mx28_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);

	/* 8 bits word length in MMC mode */
	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl1,
	SSP_CTRL1_SSP_MODE_MASK \| SSP_CTRL1_WORD_LENGTH_MASK,
	SSP_CTRL1_SSP_MODE_SD_MMC \| SSP_CTRL1_WORD_LENGTH_EIGHT_BITS);

	/* Set initial bit clock 400 KHz */
	mx28_set_ssp_busclock(priv->id, 400);

	/* Send initial 74 clock cycles (185 us @ 400 KHz)*/
	writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_set);
	udelay(200);
	writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_clr);

	return 0;
	}

	int mxsmmc_initialize(bd_t bis, int id, int (wp)(int))
	{
	struct mx28_clkctrl_regs *clkctrl_regs =
	(struct mx28_clkctrl_regs *)MXS_CLKCTRL_BASE;
	struct mmc *mmc = NULL;
	struct mxsmmc_priv *priv = NULL;

	mmc = malloc(sizeof(struct mmc));
	if (!mmc)
	return -ENOMEM;

	priv = malloc(sizeof(struct mxsmmc_priv));
	if (!priv) {
	free(mmc);
	return -ENOMEM;
	}

	priv->mmc_is_wp = wp;
	priv->id = id;
	switch (id) {
	case 0:
	priv->regs = (struct mx28_ssp_regs *)MXS_SSP0_BASE;
	priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP0;
	priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp0;
	break;
	case 1:
	priv->regs = (struct mx28_ssp_regs *)MXS_SSP1_BASE;
	priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP1;
	priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp1;
	break;
	case 2:
	priv->regs = (struct mx28_ssp_regs *)MXS_SSP2_BASE;
	priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP2;
	priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp2;
	break;
	case 3:
	priv->regs = (struct mx28_ssp_regs *)MXS_SSP3_BASE;
	priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP3;
	priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp3;
	break;
	}

	sprintf(mmc->name, "MXS MMC");
	mmc->send_cmd = mxsmmc_send_cmd;
	mmc->set_ios = mxsmmc_set_ios;
	mmc->init = mxsmmc_init;
	mmc->getcd = NULL;
	mmc->priv = priv;

	mmc->voltages = MMC_VDD_32_33 \| MMC_VDD_33_34;

	mmc->host_caps = MMC_MODE_4BIT \| MMC_MODE_8BIT \|
	MMC_MODE_HS_52MHz \| MMC_MODE_HS;

	/*
	* SSPCLK = 480 * 18 / 29 / 1 = 297.731 MHz
	* SSP bit rate = SSPCLK / (CLOCK_DIVIDE * (1 + CLOCK_RATE)),
	* CLOCK_DIVIDE has to be an even value from 2 to 254, and
	* CLOCK_RATE could be any integer from 0 to 255.
	*/
	mmc->f_min = 400000;
	mmc->f_max = mxc_get_clock(MXC_SSP0_CLK + id) * 1000 / 2;
	mmc->b_max = 0;

	mmc_register(mmc);
	return 0;
	}