Patchwork [U-Boot] mmc: new legacy MMC/SPI driver

login
register
mail settings
Submitter Mike Frysinger
Date April 23, 2010, 3:28 a.m.
Message ID <1271993307-10361-1-git-send-email-vapier@gentoo.org>
Download mbox | patch
Permalink /patch/71774/
State Superseded
Headers show

Comments

Mike Frysinger - April 23, 2010, 3:28 a.m.
From: Hans Eklund <hans@rubico.se>

Needs converting to generic MMC framework.

Signed-off-by: Hans Eklund <hans@rubico.se>
Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
 drivers/mmc/Makefile  |    3 +
 drivers/mmc/spi_mmc.c | 1119 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 1122 insertions(+), 0 deletions(-)
 create mode 100644 drivers/mmc/spi_mmc.c
Wolfgang Wegner - April 23, 2010, 8:20 a.m.
Hi Mike,

On Thu, Apr 22, 2010 at 11:28:27PM -0400, Mike Frysinger wrote:

> +static short mmc_spi_init_card(struct mmc_spi_dev *pdev)
> +{
> +	unsigned short cntr = 0;
> +
> +	/* for making init process beeing silent */
> +	init_mode = 1;
> +	/* save length of log for external usage */
> +	pdev->log_len = LOG_LEN;
> +
> +	/* 10 bytes(80 cycles) with CS de-asserted */
> +	mmc_spi_dummy_clocks(pdev, 10);
> +	pdev->doassert();
> +	if (send_cmd_and_wait(pdev, GO_IDLE_STATE, 0, R1_IDLE_STATE, MMC_INIT_TIMEOUT))
> +		return 1;
> +	pdev->deassert();
> +	/* Send One Byte Delay */
> +	if (pdev->write(Null_Word, 1, pdev->priv_data) < 0)
> +		return 1;
> +	pdev->doassert();
[...]

Is there any reason to use doassert() and deassert() except to generate
the "dummy" cycles needed to initialize the card? Which driver does
_need_ an explicit cs_activate() and cs_deactivate() outside the
write() and read() functions?

CS control is done automatically by most drivers. According to
include/spi.h, the _board_code_ is supposed to supply spi_cs_[de]activate()
to be used by the driver in case the hardware can not control the chip
selects automatically. The documentation is not clear about it, but
from my point of view spi_cs_[de]activate() are not part of the
SPI API.

I think we should not clutter client drivers with such implementation
specific things.

I have to clean up my code and try to migrate to your newer code base,
but I did implement a modified version using SPI_XFER_BEGIN,
spi_setup_slave() (to clear the CS) and SPI_CS_HIGH to achieve the
CS switching in a way compliant with e.g. the coldfire SPI driver.
(Although IIRC I had to add SPI_CS_HIGH there, too)

Regards,
Wolfgang
Mike Frysinger - April 23, 2010, 2:55 p.m.
On Friday 23 April 2010 04:20:34 Wolfgang Wegner wrote:
> On Thu, Apr 22, 2010 at 11:28:27PM -0400, Mike Frysinger wrote:
> > +static short mmc_spi_init_card(struct mmc_spi_dev *pdev)
> > +{
> > +	unsigned short cntr = 0;
> > +
> > +	/* for making init process beeing silent */
> > +	init_mode = 1;
> > +	/* save length of log for external usage */
> > +	pdev->log_len = LOG_LEN;
> > +
> > +	/* 10 bytes(80 cycles) with CS de-asserted */
> > +	mmc_spi_dummy_clocks(pdev, 10);
> > +	pdev->doassert();
> > +	if (send_cmd_and_wait(pdev, GO_IDLE_STATE, 0, R1_IDLE_STATE,
> > MMC_INIT_TIMEOUT)) +		return 1;
> > +	pdev->deassert();
> > +	/* Send One Byte Delay */
> > +	if (pdev->write(Null_Word, 1, pdev->priv_data) < 0)
> > +		return 1;
> > +	pdev->doassert();
> 
> [...]
> 
> Is there any reason to use doassert() and deassert() except to generate
> the "dummy" cycles needed to initialize the card? Which driver does
> _need_ an explicit cs_activate() and cs_deactivate() outside the
> write() and read() functions?

i have no idea.  i didnt write the driver.
-mike

Patch

diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 6fa04b8..1b8f5bd 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -23,6 +23,9 @@ 
 
 include $(TOPDIR)/config.mk
 
+# stick it up here to avoid conflicts
+COBJS-$(CONFIG_SPI_MMC) += spi_mmc.o
+
 LIB	:= $(obj)libmmc.a
 
 COBJS-$(CONFIG_GENERIC_MMC) += mmc.o
diff --git a/drivers/mmc/spi_mmc.c b/drivers/mmc/spi_mmc.c
new file mode 100644
index 0000000..7ce9ce1
--- /dev/null
+++ b/drivers/mmc/spi_mmc.c
@@ -0,0 +1,1119 @@ 
+/*
+ * SPI-MMC/SD Protocol.
+ *
+ * Copyright (C) 2005-2007, Rubico AB (www.rubico.se)
+ *
+ * Developed as a part the CDT project C4 (www.cdt.ltu.se).
+ *
+ * Robert Selberg, <robert@rubico.se>
+ * Hans Eklund, <hans@rubico.se>
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+/*
+ * TODO: Correct Multiple block read and write functions. Didnt have time
+ *	to make them all failsafe. Will be done soon.
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <spi.h>
+#include <mmc.h>
+
+enum {
+	MMC_INIT_TIMEOUT 	= 30000,
+	MMC_COMMAND_TIMEOUT	= 5000,
+	MMC_PROG_TIMEOUT	= 500000,
+	BUSY_BLOCK_LEN 		= 1,
+	BUSY_BLOCK_LEN_SHORT	= 16,
+	MMC_SECTOR_SIZE		= 512,
+	SD_PRE_CMD_ZEROS	= 4,
+	SD_CLK_CNTRL		= 2,
+	LOG_LEN			= 16,
+	WRB_LEN			= 256,
+
+/* Card command classes */
+
+/* Internal error codes */
+	ERR_SPI_TIMEOUT		= 0xF1,
+	ERR_MMC_TIMEOUT		= 0xF2,
+	ERR_MMC_PROG_TIMEOUT 	= 0xF3,
+	ERR_UNKNOWN_TOK		= 0xF4,
+
+/* return values from functions */
+	RVAL_OK			= 0,
+	RVAL_ERROR		= 1,
+	RVAL_CRITICAL		= 2,
+
+/* Format R1(b) response tokens (1 byte long) */
+	BUSY_TOKEN		= 0x00,
+	R1_OK			= 0x00,
+	R1_IDLE_STATE		= 0x01,
+	R1_ERASE_STATE		= 0x02,
+	R1_ILLEGAL_CMD		= 0x04,
+	R1_COM_CRC_ERROR	= 0x08,
+	R1_ERASE_SEQ_ERROR	= 0x10,
+	R1_ADDRESS_ERROR	= 0x20,
+	R1_PARAMETER_ERROR	= 0x40,
+
+/* Format R2 response tokens (2 bytes long, first is same as R1 responses) */
+	R2_OK			= 0x00,
+	R2_CARD_LOCKED		= 0x01,
+	R2_WP_ERASE_SKIP	= 0x02,
+	R2_LOCK_UNLOCK_CMD_FAIL	= 0x02,
+	R2_ERROR		= 0x04,
+	R2_CC_ERROR		= 0x08,
+	R2_CARD_ECC_FAILED	= 0x10,
+	R2_WP_VIOLATION		= 0x20,
+	R2_ERASE_PARAM		= 0x40,
+	R2_OUT_OF_RANGE		= 0x80,
+	R2_CSD_OVERWRITE	= 0x80,
+/* TODO: Format R3 response tokens */
+
+/* Data response tokens */
+	DR_MASK			= 0x0F,
+	DR_ACCEPTED		= 0x05,
+	DR_CRC_ERROR		= 0x0B,
+	DR_WRITE_ERROR		= 0x0D,
+
+/*
+ Data tokens (4 bytes to (N+3) bytes long), N is data block len
+ format of the Start Data Block Token
+*/
+	SBT_S_BLOCK_READ	= 0xFE,
+	SBT_M_BLOCK_READ	= 0xFE,
+	SBT_S_BLOCK_WRITE	= 0xFE,
+	SBT_M_BLOCK_WRITE 	= 0xFC,
+	STT_M_BLOCK_WRITE	= 0xFD,
+
+/* Data error tokens (1 byte long) */
+	DE_ERROR		= 0x01,
+	DE_CC_ERROR		= 0x02,
+	DE_CARD_ECC_FAILED	= 0x04,
+	DE_OUT_OF_RANGE		= 0x08,
+	DE_CARD_IS_LOCKED	= 0x10,
+
+/* MMC/SD SPI mode commands */
+	GO_IDLE_STATE		= 0,
+	SEND_OP_COND		= 1,
+	SEND_CSD		= 9,
+	SEND_CID		= 10,
+	STOP_TRANSMISSION	= 12,
+	SEND_STATUS		= 13,
+	SET_BLOCKLEN		= 16,
+	READ_SINGLE_BLOCK	= 17,
+	READ_MULTIPLE_BLOCK	= 18,
+	WRITE_BLOCK		= 24,
+	WRITE_MULTIPLE_BLOCK	= 25,
+	SD_SEND_OP_COND		= 41,
+	APP_CMD			= 55,
+};
+
+/* minimal local versions of CSD/CID structures,
+   somewhat ripped from linux MMC layer, the entire
+   CSD struct is larger and is not completley parsed
+*/
+struct cid_str {
+	unsigned int		manfid;
+	char			prod_name[8];
+	unsigned int		serial;
+	unsigned short		oemid;
+	unsigned short		year;
+	unsigned char		hwrev;
+	unsigned char		fwrev;
+	unsigned char		month;
+};
+
+struct csd_str {				/* __csd field name__*/
+	unsigned char		mmca_vsn;	/* CSD_STRUCTURE */
+	unsigned short		cmdclass;	/* CCC */
+	unsigned short		tacc_clks;	/* TAAC */
+	unsigned int		tacc_ns;	/* NSAC */
+	unsigned int		max_dtr;	/* TRANS_SPEED */
+	unsigned int		read_blkbits;	/* READ_BL_LEN */
+	unsigned int		capacity;
+};
+
+/*
+ mmc_spi_dev - Implementation need to configure this struct
+ with callback functions to read and write data that the
+ mmc_spi function can use for its operations.
+ NOTE: Every function defined here expect exclusive access to
+ any MMC/SD card it is operating on. Functions should be considered
+ critical sections. Also note that the read/write callbacks may a mutex
+ if they can be executed by another context.
+*/
+struct mmc_spi_dev {
+	int		(*read)(unsigned char *buf, unsigned int nbytes, void *priv_data);
+	int		(*write)(unsigned char *buf, unsigned int nbytes, void *priv_data);
+	void	(*doassert)(void);
+	void	(*deassert)(void);
+	void		*priv_data;	/* incomming pointer to private data for callbacks */
+	unsigned char 	raw_csd[18];	/* raw csd data to use with external parser */
+	unsigned char 	raw_cid[18];	/* raw cid data to use with external parser */
+	struct cid_str 	cid;		/* internal represent. of cid data */
+	struct csd_str 	csd;		/* internal represent. of csd data */
+	int		sd;					/* true if SD card found */
+	int		log_len;
+	unsigned int	est_write_lat;	/* [bytes] */
+	unsigned short	force_cs_high;	/* true if write/read callbacks should ask for CS high */
+	unsigned int	errors;		/* total amount of errors recorded since card insertion */
+	unsigned char	cmd_log[LOG_LEN];
+	unsigned short	error_log[LOG_LEN];
+	unsigned short	status_log[LOG_LEN]; /* Status is not checked anymore since some cards will cry */
+};
+
+
+static unsigned char mmc_cmd[6] = {0x40, 0x00, 0x00, 0x00, 0x00, 0x95};
+static unsigned char Null_Word[10] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+					0xFF, 0xFF, 0xFF};
+static unsigned char latest_cmd;
+
+static int init_mode = 1;
+
+
+#if 0
+/**********************************************************************\
+*
+* MMC CSD/CID related, could be somewhat trimmed and cleaned
+*
+\**********************************************************************/
+static unsigned char getbit(void *ptr, unsigned int n)
+{
+	unsigned int byte_nr;
+	unsigned int bit_nr;
+
+	byte_nr = n/8;
+	bit_nr = n % 8;
+
+	return (unsigned char)(((unsigned char *)ptr)[byte_nr] >> bit_nr) & 1;
+}
+
+static unsigned int getvalue(void *ptr, unsigned int n, unsigned int len)
+{
+	unsigned int value = 0;
+	int i = 0;
+
+	for (i = 0; i < len; i++)
+		value += ((unsigned int)getbit(ptr, n+i)) << i;
+	return value;
+}
+#endif
+
+static unsigned char mmc_wait_response(struct mmc_spi_dev *pdev, unsigned int timeout)
+{
+	unsigned char card_resp = 0xFF;
+	unsigned int n = 0;
+	/* reset time and set to timeout ms */
+	while (1) {
+
+		if (pdev->read(&card_resp, 1, pdev->priv_data) < 0) {
+			debug("error: mmc_wait_response read error\n");
+			return ERR_SPI_TIMEOUT;
+		}
+		if (card_resp != 0xFF)
+			return card_resp;
+		/*
+		 NOTE: "timeout" in seconds may not be a good idea after all
+		 (by doing pdev->elapsed_time() )
+		 wait for a specific amount of polls for now.
+		*/
+		if ((n++ >= timeout)) {
+			debug("hey! timed out after %d since %d bytes was maximum(latest_cmd=%d)\n", n,
+				timeout, latest_cmd);
+			return ERR_MMC_TIMEOUT;
+		}
+	}
+}
+
+static short mmc_spi_read_status(struct mmc_spi_dev *pdev)
+{
+	unsigned char b1 = 0;
+	unsigned char b2 = 0;
+	unsigned short r2 = 0xffff;
+	static unsigned char status_cmd[6] = {0x4D, 0x00, 0x00, 0x00, 0x00, 0x95};
+
+	pdev->doassert();
+
+	if (pdev->sd) {
+		if (pdev->write(Null_Word, SD_PRE_CMD_ZEROS, pdev->priv_data) < 0) {
+			debug("sending SD_PRE_CMD_ZEROS failed\n");
+			pdev->deassert();
+			return ERR_SPI_TIMEOUT;
+		}
+	}
+	if (pdev->write(status_cmd, 6, pdev->priv_data) < 0) {
+		debug("sending of SEND_STATUS command failed\n");
+		pdev->deassert();
+		return ERR_SPI_TIMEOUT;
+	}
+	b1 = mmc_wait_response(pdev, MMC_COMMAND_TIMEOUT);
+	b2 = mmc_wait_response(pdev, MMC_COMMAND_TIMEOUT);
+
+	if (b1 == ERR_MMC_TIMEOUT || b2 == ERR_MMC_TIMEOUT) {
+		debug("No status received !\n");
+		pdev->deassert();
+		return ERR_MMC_TIMEOUT;
+	}
+
+	r2 = b2 + (b1 << 8);
+
+	if (r2)
+		debug("STATUS r2: 0x%04x\n", r2);
+	pdev->deassert();
+
+	return r2;
+
+	/* TODO: Implement in a finer way */
+	switch (b1) {
+	case R1_OK:
+		break;
+	case R1_IDLE_STATE:
+		printf("R1_IDLE_STATE\n");
+		break;
+	case R1_ERASE_STATE:
+		printf("R1_ERASE_STATE\n");
+		break;
+	case R1_ILLEGAL_CMD:
+		printf("R1_ILLEGAL_COMMAND\n");
+		break;
+	case R1_COM_CRC_ERROR:
+		printf("R1_COM_CRC_ERROR\n");
+		break;
+	case R1_ERASE_SEQ_ERROR:
+		printf("R1_ERASE_SEQ_ERROR\n");
+		break;
+	case R1_ADDRESS_ERROR:
+		printf("R1_ADDRESS_ERROR\n");
+		break;
+	case R1_PARAMETER_ERROR:
+		printf("R1_PARAMETER_ERROR\n");
+		break;
+	case 0xFF:
+		printf("b1: STATUS RESPONSE TIMEOUT\n");
+		break;
+	default:
+		printf("b1: INVALID STATUS RESPONSE(0x%02x)\n", b1);
+		break;
+	}
+
+	switch (b2) {
+	case R2_OK:
+		break;
+	case R2_CARD_LOCKED:
+		printf("R2_CARD_LOCKED\n");
+		break;
+	case R2_WP_ERASE_SKIP:
+		printf("R2_WP_ERASE_SKIP/Unlock command failed\n");
+		break;
+	case R2_ERROR:
+		printf("R2_ERROR\n");
+		break;
+	case R2_CC_ERROR:
+		printf("R2_CC_ERROR\n");
+		break;
+	case R2_CARD_ECC_FAILED:
+		printf("R2_CARD_ECC_FAILED\n");
+		break;
+	case R2_WP_VIOLATION:
+		printf("R2_WP_VIOLATION\n");
+		break;
+	case R2_ERASE_PARAM:
+		printf("R2_ERASE_PARAM\n");
+		break;
+	case R2_OUT_OF_RANGE:
+		printf("R2_OUT_OF_RANGE, CSD_Overwrite\n");
+		break;
+	case 0xFF:
+		printf("b2: STATUS RESPONSE TIMEOUT\n");
+		break;
+	default:
+		printf("b2: INVALID STATUS RESPONSE(0x%02x)\n", b2);
+		break;
+	}
+
+	return r2;
+}
+
+#if 0
+static void mmc_spi_fill_card_struct(struct mmc_spi_dev *pdev)
+{
+	unsigned short c_size_mult = 0;
+	unsigned short c_size = 0;
+	unsigned char *raw_csd;
+	unsigned char *raw_cid;
+
+	/* local, shorter names, just to keep lines below shorter */
+	raw_csd = pdev->raw_csd;
+	raw_cid = pdev->raw_cid;
+	pdev->csd.mmca_vsn = (raw_csd[0] & 0x3c) >> 2;
+	pdev->csd.cmdclass = (((__u16)raw_csd[4]) << 4) | ((raw_csd[5] & 0xf0) >> 4);
+	pdev->csd.tacc_clks = raw_csd[1];
+	pdev->csd.tacc_ns = raw_csd[2];
+	pdev->csd.max_dtr = raw_csd[3];
+	pdev->csd.read_blkbits = raw_csd[5] & 0x0f;
+	/* for calculating capacity(in blocks) */
+	c_size = ((((__u16)raw_csd[6]) & 0x03) << 10) | (((__u16)raw_csd[7]) << 2) |
+		(((__u16)raw_csd[8]) & 0xc0) >> 6;
+	c_size_mult = ((raw_csd[9] & 0x03) << 1) | ((raw_csd[10] & 0x80) >> 7);
+	pdev->csd.capacity = (c_size+1) * (1 << (c_size_mult + 2));
+	pdev->cid.manfid = getvalue(raw_cid, 127-127, 8);
+	memcpy(pdev->cid.prod_name, raw_cid+3, 7);
+	pdev->cid.serial = getvalue(raw_cid, 127-47, 32);
+	pdev->cid.oemid = getvalue(raw_cid, 127-119, 16);
+	pdev->cid.year = 1997 + (getvalue(raw_cid, 127-15, 8) & 0x0F);
+	pdev->cid.hwrev = (getvalue(raw_cid, 127-55, 8) & 0xF0) >> 4;
+	pdev->cid.fwrev = getvalue(raw_cid, 127-55, 8) & 0x0F;
+	pdev->cid.month = (getvalue(raw_cid, 127-15, 8) & 0xF0) >> 4;
+}
+#endif
+
+static short mmc_spi_dummy_clocks(struct mmc_spi_dev *pdev, unsigned short nbytes)
+{
+	int i;
+
+	pdev->force_cs_high = 1;
+	for (i = 0; i < nbytes; i++) {
+		if (pdev->write(Null_Word, 1, pdev->priv_data) < 0) {
+			pdev->force_cs_high = 0;
+			return 1;
+		}
+	}
+	pdev->force_cs_high = 0;
+
+	return 0;
+}
+
+static short send_cmd_and_wait(struct mmc_spi_dev *pdev,
+			       unsigned char command,
+			       unsigned int argument,
+			       unsigned short cmd_resp,
+			       unsigned int timeout)
+{
+	unsigned short resp = 0xff;
+	unsigned short rval = 0;
+	/* Build command string */
+	mmc_cmd[0] = 0x40 + command;
+	mmc_cmd[1] = (unsigned char)(argument >> 24 & 0xff);
+	mmc_cmd[2] = (unsigned char)(argument >> 16 & 0xff);
+	mmc_cmd[3] = (unsigned char)(argument >> 8 & 0xff);
+	mmc_cmd[4] = (unsigned char)(argument & 0xff);
+	mmc_cmd[5] = 0x95;
+
+	/* record last command if not in init mode */
+	if (!init_mode)
+		latest_cmd = command;
+	if (init_mode || pdev->sd) {
+		/* Send a few zeros since SDs may be sleeping */
+		if (pdev->write(Null_Word, SD_PRE_CMD_ZEROS, pdev->priv_data) < 0) {
+			debug("sending SD_PRE_CMD_ZEROS failed\n");
+			rval = ERR_SPI_TIMEOUT;
+			goto out;
+		}
+	}
+
+	if (pdev->write(mmc_cmd, 6, pdev->priv_data) < 0) {
+		debug("sending command %d failed\n", command);
+		rval = ERR_SPI_TIMEOUT;
+		goto out;
+	}
+	resp = mmc_wait_response(pdev, timeout);
+	if (resp != cmd_resp) {
+		/* NOTE: ignore "illegal command" responses */
+		if (resp == 4) {
+			rval = 0;
+			goto out;
+		}
+		/* Will only be active during init, seems to be needed by some SDs */
+		if (init_mode) {
+			/* This delay is somewhat picky for some SDs. Dont change it */
+			udelay(10000);
+		} else {
+			debug("unexpected response to command %d, wanted 0x%x, got 0x%x)\n",
+				command, cmd_resp, resp);
+		}
+		rval =  ERR_MMC_TIMEOUT;
+		goto out;
+	}
+out:
+	/*
+	if (pdev->sd) {
+		mmc_spi_dummy_clocks(pdev, SD_CLK_CNTRL);
+	}
+	*/
+	return rval;
+}
+
+static short mmc_spi_error_handler(struct mmc_spi_dev *pdev, short rval)
+{
+	/* Handle log index, wrap if necessary */
+	unsigned short status = 0;
+
+	/* If error, check status and log */
+	if (rval) {
+		/* shift old log entries down */
+		memcpy(pdev->error_log+1, pdev->error_log, LOG_LEN-1);
+		memcpy(pdev->status_log+1, pdev->status_log, LOG_LEN-1);
+		memcpy(pdev->cmd_log+1, pdev->cmd_log, LOG_LEN-1);
+		pdev->cmd_log[0] = latest_cmd;
+		pdev->error_log[0] = rval;
+
+		/*
+		 NOTE: status may be zero even on errors.
+		 since data lines may be left low(if card pulled from socket for ex.)
+		*/
+		status = mmc_spi_read_status(pdev);
+		pdev->status_log[0] =  status;
+		pdev->errors++;
+
+	debug("Latest command was: %d\n", latest_cmd);
+	}
+	switch (rval) {
+	case ERR_SPI_TIMEOUT:
+	debug("ERR_SPI_TIMEOUT\n");
+		return RVAL_CRITICAL;
+	case ERR_MMC_TIMEOUT:
+		debug("ERR_MMC_TIMEOUT\n");
+		return RVAL_ERROR;
+	case ERR_MMC_PROG_TIMEOUT:
+	case ERR_UNKNOWN_TOK:
+	case DR_CRC_ERROR:
+	case DR_WRITE_ERROR:
+	default:
+		if (status) {
+			return RVAL_ERROR;
+		} else {
+			/* NOTE: could use status to determine what to do more accurately */
+			return RVAL_OK;
+		}
+	}
+	return 0;
+}
+
+#if 0
+/**
+* read_mmc_reg - reads the 128 bit CSD or CID register data + 2 byte CRC
+*
+*/
+static short read_mmc_reg(struct mmc_spi_dev *pdev, short csd)
+{
+	unsigned char resp = 0xff;
+	unsigned char *buf;
+	unsigned short rval = 0;
+
+	pdev->doassert();
+	if (csd) {
+		rval = send_cmd_and_wait(pdev, SEND_CSD, 0, R1_OK, MMC_COMMAND_TIMEOUT);
+		if (rval)
+			goto out;
+		buf = pdev->raw_csd;
+	} else {
+		rval = send_cmd_and_wait(pdev, SEND_CID, 0, R1_OK, MMC_COMMAND_TIMEOUT);
+		if (rval)
+			goto out;
+		buf = pdev->raw_cid;
+	}
+
+	/* start block token */
+	resp = mmc_wait_response(pdev, MMC_COMMAND_TIMEOUT);
+	if (resp != SBT_S_BLOCK_READ) {
+		debug("mmc did not send 0xFE(got 0x%x)\n", resp);
+		rval = resp;
+		goto out;
+	}
+	if (pdev->read(buf, 18, pdev->priv_data) < 18) {
+		debug("reading 18 bytes of data failed\n");
+		rval = ERR_SPI_TIMEOUT;
+		goto out;
+	}
+out:
+	/* send clocks for SD cards */
+	if (pdev->sd)
+		mmc_spi_dummy_clocks(pdev, SD_CLK_CNTRL);
+
+	pdev->deassert();
+
+	/* check for errors, but dont change rval */
+	mmc_spi_error_handler(pdev, rval);
+
+	return rval;
+}
+
+static short mmc_spi_get_card(struct mmc_spi_dev *pdev)
+{
+	if (read_mmc_reg(pdev, 1)) {
+		debug("CSD register read failed.\n");
+		return 1;
+	}
+	if (read_mmc_reg(pdev, 0)) {
+		debug("CID register read failed.\n");
+		return 1;
+	}
+
+	/* Parse CSD and CID data */
+	mmc_spi_fill_card_struct(pdev);
+
+	return 0;
+}
+#endif
+
+static short mmc_spi_read_mmc_block(struct mmc_spi_dev *pdev, unsigned char *buf, unsigned long address)
+{
+	unsigned char resp = 0xff;
+	unsigned short rval = 0;
+
+	pdev->doassert();
+	rval = send_cmd_and_wait(pdev, READ_SINGLE_BLOCK, address, R1_OK, MMC_COMMAND_TIMEOUT);
+	if (rval)
+		goto out;
+
+	/* Poll for start block token */
+	resp = mmc_wait_response(pdev, MMC_COMMAND_TIMEOUT);
+	if (resp != SBT_S_BLOCK_READ) {
+		debug("mmc did not send 0xFE(got 0x%x)\n", resp);
+		rval = resp;
+		goto out;
+	}
+	/* Read data */
+	if (pdev->read(buf, 512, pdev->priv_data) < 512) {
+		debug("reading 512 bytes of data failed\n");
+		rval = ERR_SPI_TIMEOUT;
+		goto out;
+	}
+	/* TODO: read CRC */
+out:;
+
+	/* send 8 clocks for SD cards */
+	if (pdev->sd)
+		mmc_spi_dummy_clocks(pdev, SD_CLK_CNTRL);
+	pdev->deassert();
+
+	return mmc_spi_error_handler(pdev, rval);
+}
+
+/*
+ Not implemented on Blackfin since DMA reads are a bit troublesome(512 bytes
+ requested could be 514 bytes read.. this could be solved with some hacks though)
+*/
+#ifdef USE_MULT_BLOCK_READS
+static short mmc_spi_read_mult_mmc_block(struct mmc_spi_dev *pdev, unsigned char *buf,
+	unsigned int address, int nblocks)
+{
+	unsigned char resp = 0xff;
+	int rval = 0;
+	int i = 0;
+
+	rval = send_cmd_and_wait(pdev, READ_MULTIPLE_BLOCK, address, R1_OK, MMC_COMMAND_TIMEOUT)
+	if (rval)
+		goto out;
+
+	/* idea: read n blocks in one swoop, Data, Garbage and Tokens
+	* GGGGGTDDD..512..DDDGGGGTDDDD..512..DDDGGGGT - - -
+	*-------'''''''''''''.....''''''''''''''
+	* Then memcpy data to the real buffer, may need a few pages of memory for this
+	*/
+	for (i = 0; i < nblocks; i++) {
+		/* Poll for start block token */
+		resp = mmc_wait_response(pdev, MMC_COMMAND_TIMEOUT)
+		if (resp != SBT_M_BLOCK_READ) {
+			debug("mmc did not send 0xFE(got 0x%x)\n", resp);
+			rval = resp;
+			goto out;
+		}
+		if (pdev->read(buf+i*MMC_SECTOR_SIZE, MMC_SECTOR_SIZE, pdev->priv_data) < MMC_SECTOR_SIZE) {
+			debug("reading 512 bytes of data failed\n");
+			rval = 1;
+			goto out;
+		}
+	}
+	rval = 0;
+out:
+
+	/* send 8 clocks for SD cards */
+	if (pdev->sd)
+		mmc_spi_dummy_clocks(pdev, SD_CLK_CNTRL);
+
+	/* send stop command */
+	rval = send_cmd_and_wait(pdev, STOP_TRANSMISSION, address, R1_OK, MMC_COMMAND_TIMEOUT))) {
+
+	return mmc_spi_error_handler(pdev, rval);
+}
+
+static short mmc_spi_write_mmc_block(struct mmc_spi_dev *pdev, unsigned char *buf, unsigned int address)
+{
+	unsigned short rval = 0;
+	unsigned char resp = 0xff;
+	unsigned char token;
+	unsigned int n_polls = 0;
+
+	pdev->doassert();
+	rval = send_cmd_and_wait(pdev, WRITE_BLOCK, address, R1_OK, MMC_COMMAND_TIMEOUT);
+	if (rval) {
+		debug("write error at %08x \n", address);
+		goto out;
+	}
+
+	/* send start block token */
+	token = SBT_S_BLOCK_WRITE;
+	if (pdev->write(&token, 1, pdev->priv_data) < 0) {
+		debug("sending START_BLOCK_TOKEN failed\n");
+		rval = ERR_SPI_TIMEOUT;
+		goto out;
+
+	}
+	/* transmit data block */
+	if (pdev->write(buf, MMC_SECTOR_SIZE, pdev->priv_data) < MMC_SECTOR_SIZE) {
+		debug("transmission of 512 bytes failed\n");
+		rval = ERR_SPI_TIMEOUT;
+		goto out;
+
+	}
+	resp = mmc_wait_response(pdev, MMC_COMMAND_TIMEOUT) & DR_MASK;
+	/* wait for data response token */
+	if (resp != DR_ACCEPTED) {
+		/*
+		 some card seem to send 0 or 1 at this point,
+		 accet that even though not according to MMC spec.
+		*/
+		if (resp != 0 && resp != 1 && resp != 4) {
+			debug("mmc did not send DR_ACCEPTED token(got R1=0x%x)\n", resp);
+			rval = ERR_MMC_TIMEOUT;
+			goto out;
+		}
+	}
+
+	while (1) {
+		/*
+		 NOTE: could read response block-wise(effecive if DMA is utilized) to buffer
+		 and check for tokens.
+		*/
+		if (pdev->read(&resp, 1, pdev->priv_data) < 0) {
+			debug("busy token read polling failed\n");
+			rval = resp;
+			goto out;
+		}
+		switch (resp & DR_MASK) {
+		case BUSY_TOKEN:
+			break;
+		case DR_ACCEPTED:
+			goto out;
+		case DR_CRC_ERROR:
+			rval = DR_CRC_ERROR;
+			goto out;
+		case DR_WRITE_ERROR:
+			rval = DR_WRITE_ERROR;
+			goto out;
+		default:
+			goto out;
+		}
+		if (n_polls++ >= MMC_PROG_TIMEOUT) {
+			rval = ERR_MMC_PROG_TIMEOUT;
+			goto out;
+		}
+	}
+out:
+	/* send 8 clocks for SD cards */
+	if (pdev->sd)
+		mmc_spi_dummy_clocks(pdev, SD_CLK_CNTRL);
+
+	pdev->deassert();
+
+	return mmc_spi_error_handler(pdev, rval);
+}
+
+static unsigned char wrb[WRB_LEN];
+
+static short mmc_spi_write_mult_mmc_block(struct mmc_spi_dev *pdev,
+	unsigned char *buf, unsigned int address, int nblocks)
+{
+	unsigned short rval = 0;
+	unsigned char resp = 0xff;
+	unsigned char resp_last = 0xff;
+	unsigned char resp_oldest = 0xff;
+	unsigned int tc = 0;
+	int i = 0;
+	unsigned char token;
+	unsigned int n_polls = 0;
+
+
+	debug("adr(r): %08x\n", address);
+	pdev->doassert();
+	rval = send_cmd_and_wait(pdev, WRITE_MULTIPLE_BLOCK, address, R1_OK, MMC_COMMAND_TIMEOUT);
+	if (rval) {
+		debug("NO MBW!!!\n");
+		goto out;
+	}
+
+	for (i = 0; i < nblocks; i++) {
+		/* send start block token */
+		token = SBT_M_BLOCK_WRITE;
+		if (pdev->write(&token, 1, pdev->priv_data) < 0) {
+			debug("sending START_BLOCK_TOKEN failed\n");
+			rval = ERR_SPI_TIMEOUT;
+			goto stop;
+
+		}
+		/* transmit data block */
+		if (pdev->write(buf+i*MMC_SECTOR_SIZE, MMC_SECTOR_SIZE, pdev->priv_data) < MMC_SECTOR_SIZE) {
+			debug("transmission of 512 bytes failed\n");
+			rval = ERR_SPI_TIMEOUT;
+			goto stop;
+
+		}
+		/* wait for data response token */
+		resp = mmc_wait_response(pdev, MMC_COMMAND_TIMEOUT) & DR_MASK;
+		if (resp != DR_ACCEPTED) {
+			if (resp != 0 && resp != 1 && resp != 2 && resp != 4) {
+				debug("mmc did not send DR_ACCEPTED token(got R1=0x%x)\n", resp);
+				rval = ERR_MMC_TIMEOUT;
+				goto stop;
+			}
+		}
+		/* send 8 clocks for SD cards */
+		if (pdev->sd)
+			mmc_spi_dummy_clocks(pdev, SD_CLK_CNTRL);
+		/* wait on busy/error token while MMC is programming new data */
+		tc = 0;
+		n_polls = 0;
+
+		while (1) {
+			/* read response byte-wise(take one or two reads only) */
+			if (pdev->read(&resp, 1, pdev->priv_data) < 0) {
+				debug("busy token read polling failed\n");
+				rval = ERR_SPI_TIMEOUT;
+				goto stop;
+			}
+			switch (resp & DR_MASK) {
+			case BUSY_TOKEN:
+				break;
+			case DR_ACCEPTED:
+				goto next;
+			case DR_CRC_ERROR:
+				rval = DR_CRC_ERROR;
+				goto stop;
+			case DR_WRITE_ERROR:
+				rval = DR_WRITE_ERROR;
+				goto stop;
+			default:
+				goto next;
+			}
+			if (n_polls++ >= MMC_PROG_TIMEOUT) {
+				rval = ERR_MMC_PROG_TIMEOUT;
+				goto stop;
+			}
+		}
+next:;
+	}
+
+stop:
+	/* send stop tran token (STT_M_BLOCK_WRITE) */
+	token = STT_M_BLOCK_WRITE;
+	if (pdev->write(&token, 1, pdev->priv_data) < 0) {
+		debug("sending STT_M_BLOCK_WRITE failed\n");
+		rval = ERR_SPI_TIMEOUT;
+		goto out;
+	}
+
+	n_polls = 0;
+	/*
+	 wait on final busy/error token while MMC is programming new data.
+	 This is done in blocks of length WRB_LEN instead of 1-byte poll
+	 (takes several 100 bytes to do at 20Mhz spi clock). Could decrease burst
+	 preformance on very fast cards. But improves over-all system performance
+	 immensley when using this driver.
+	*/
+	while (1 && !rval) {
+		/* read response block wise */
+		if (pdev->read(wrb, WRB_LEN, pdev->priv_data) < 0) {
+			debug("busy token read polling failed");
+			rval = ERR_SPI_TIMEOUT;
+			goto out;
+		}
+		if (n_polls++ >= MMC_PROG_TIMEOUT) {
+			debug("POLL for last token timeout!!(resp=%x, last_resp=%x, resp_oldest=%x)\n",
+				resp, resp_last, resp_oldest);
+			rval = ERR_MMC_TIMEOUT;
+			goto out;
+		}
+
+		/*
+		 Exit when card raises the data line(busy to done token transition)
+		 NOTE: transition is often(allways?) 0x00, 0x00, 0x??, 0xFF, 0xFF,
+		 where ?? could be anything != 0xFF for some card brands. Nothing
+		 to do but ignore this last "token". This was a beast and caused trouble
+		 with some off-brands. Either my interpretations of MMC/SD spec was bad.
+		 Or some cards are just sloppy made.
+		*/
+		if (wrb[WRB_LEN-1] == 0xFF) {
+			debug("Got final MBW busy wait done(as 0x%x after %d reads @ %08x.. "
+				"last_resp=%x, resp_oldest=%x\n", wrb[WRB_LEN-1], n_polls, address,
+					resp_last, resp_oldest);
+			goto out;
+		}
+		resp_oldest = resp_last;
+		resp_last = resp;
+	}
+out:
+
+	/* send 8 clocks for SD cards */
+	if (pdev->sd)
+		mmc_spi_dummy_clocks(pdev, SD_CLK_CNTRL);
+
+	pdev->deassert();
+
+	/* Reading status breaks compatibility with some cards, skip it */
+	return mmc_spi_error_handler(pdev, rval);
+}
+#endif
+
+static short mmc_spi_init_card(struct mmc_spi_dev *pdev)
+{
+	unsigned short cntr = 0;
+
+	/* for making init process beeing silent */
+	init_mode = 1;
+	/* save length of log for external usage */
+	pdev->log_len = LOG_LEN;
+
+	/* 10 bytes(80 cycles) with CS de-asserted */
+	mmc_spi_dummy_clocks(pdev, 10);
+	pdev->doassert();
+	if (send_cmd_and_wait(pdev, GO_IDLE_STATE, 0, R1_IDLE_STATE, MMC_INIT_TIMEOUT))
+		return 1;
+	pdev->deassert();
+	/* Send One Byte Delay */
+	if (pdev->write(Null_Word, 1, pdev->priv_data) < 0)
+		return 1;
+	pdev->doassert();
+	/* Look for SD card */
+	for (cntr = 0; cntr < 60; cntr++) {
+		/* Send One Byte Delay */
+		if (pdev->write(Null_Word, 1, pdev->priv_data) < 0)
+			return 1;
+		if (send_cmd_and_wait(pdev, APP_CMD, 0, R1_OK, MMC_INIT_TIMEOUT) == 0)
+			goto next;
+		if (send_cmd_and_wait(pdev, APP_CMD, 0, R1_IDLE_STATE, MMC_INIT_TIMEOUT))
+			continue;
+next:
+		if (send_cmd_and_wait(pdev, SD_SEND_OP_COND, 0, R1_OK, MMC_INIT_TIMEOUT) == 0) {
+			/* Send One Byte Delay and return */
+			if (pdev->write(Null_Word, 4, pdev->priv_data) < 0) {
+				pdev->deassert();
+				return 1;
+			}
+			pdev->sd = 1;
+			init_mode = 0;
+			debug("SD card found!\n");
+			pdev->deassert();
+			return 0;
+		}
+	}
+
+	/* poll card by sending CMD1 and wait for card initialization complete */
+	for (cntr = 0; cntr < 60; cntr++) {
+		if (send_cmd_and_wait(pdev, SEND_OP_COND, 0, R1_OK, MMC_INIT_TIMEOUT) == 0) {
+			if (pdev->write(Null_Word, 1, pdev->priv_data) < 0) {
+				pdev->deassert();
+				return 1;
+			}
+			pdev->sd = 0;
+			init_mode = 0;
+			debug("MMC card found!\n");
+			pdev->deassert();
+			return 0;
+		}
+		if (pdev->write(Null_Word, 1, pdev->priv_data) < 0) {
+			pdev->deassert();
+			return 1;
+		}
+	}
+	debug("doh!\n\n\n");
+	pdev->deassert();
+		return 1;
+}
+
+#ifdef DEBUG_REGS
+static short mmc_spi_mmc_spi_get_card_old(struct mmc_spi_dev *pdev)
+{
+	int i;
+	struct mmc_card *card = pdev->private_data->card;
+	unsigned char raw_csd[18];
+	unsigned char raw_cid[18];
+	unsigned short c_size_mult = 0;
+	unsigned short c_size = 0;
+	unsigned short read_bl_len = 0;
+	unsigned int cap = 0;
+
+	memset(raw_cid, 0, 18);
+	memset(raw_csd, 0, 18);
+
+	if (read_mmc_reg(pdev, raw_cid, 0)) {
+		debug("CSD register read failed.\n");
+		return 1;
+	};
+	if (read_mmc_reg(pdev, raw_csd, 1)) {
+		debug("CID register read failed.\n");
+		return 1;
+	}
+
+	/********** NO DEBUG CODE FROM HERE *********************/
+	card->csd.mmca_vsn = (raw_csd[0] & 0x3c) >> 2;
+	card->csd.cmdclass = (((__u16)raw_csd[4]) << 4) | ((raw_csd[5] & 0xf0) >> 4);
+	card->csd.tacc_clks = raw_csd[1];
+	card->csd.tacc_ns = raw_csd[2];
+	card->csd.max_dtr = raw_csd[3];
+	card->csd.read_blkbits = raw_csd[5] & 0x0f;
+
+	/* for calculating capacity(in blocks) */
+	c_size = ((((__u16)raw_csd[6]) & 0x03) << 10) | (((__u16)raw_csd[7]) << 2) | (((__u16)raw_csd[8]) & 0xc0) >> 6;
+	c_size_mult = ((raw_csd[9] & 0x03) << 1) | ((raw_csd[10] & 0x80) >> 7);
+	read_bl_len = raw_csd[5] & 0x0f;
+	card->csd.capacity = (c_size+1) * (1 << (c_size_mult + 2));
+
+	/* for printing capacity in bytes */
+	cap = (c_size+1) * (1 << (c_size_mult + 2)) * (1 << read_bl_len);
+
+	card->cid.manfid = getvalue(raw_cid, 127-127, 8);
+	memcpy(card.cid.prod_name, raw_cid+3, 7);
+	card->cid.serial = getvalue(raw_cid, 127-47, 32);
+	card->cid.oemid = getvalue(raw_cid, 127-119, 16);
+	card->cid.year = 1997 + (getvalue(raw_cid, 127-15, 8) & 0x0F);
+	card->cid.hwrev = (getvalue(raw_cid, 127-55, 8) & 0xF0) >> 4;
+	card->cid.fwrev = getvalue(raw_cid, 127-55, 8) & 0x0F;
+	card->cid.month = (getvalue(raw_cid, 127-15, 8) & 0xF0) >> 4;
+
+	printf("MMC found:\n\t Capacity: %dM\n\t Name: %s \n\t Rev: %d.%d \n\t"
+		"Date: %d/%d \n\t Serial: 0x%x (%u)\n", cap/(1024*1024),
+		card.cid.prod_name, card.cid.hwrev, card.cid.fwrev,
+		card.cid.year, card.cid.month, card.cid.serial, card.cid.serial);
+	return 0;
+}
+#endif
+
+
+#ifndef CONFIG_SPI_MMC_DEFAULT_BUS
+# define CONFIG_SPI_MMC_DEFAULT_BUS 0
+#endif
+#ifndef CONFIG_SPI_MMC_DEFAULT_CS
+# define CONFIG_SPI_MMC_DEFAULT_CS 1
+#endif
+#ifndef CONFIG_SPI_MMC_DEFAULT_SPEED
+# define CONFIG_SPI_MMC_DEFAULT_SPEED 30000000
+#endif
+#ifndef CONFIG_SPI_MMC_DEFAULT_MODE
+# define CONFIG_SPI_MMC_DEFAULT_MODE SPI_MODE_3
+#endif
+
+#define MMC_BLOCK_SIZE 512
+
+static block_dev_desc_t mmc_block_dev_desc;
+static struct mmc_spi_dev msdev;
+
+block_dev_desc_t *mmc_get_dev(int dev)
+{
+    debug("mmc_get_dev\n");
+    return (block_dev_desc_t *)&mmc_block_dev_desc;
+}
+
+static int r;
+unsigned long mmc_block_read(int dev, unsigned long blk_start, lbaint_t blkcnt, void *dst2)
+{
+	int i;
+	unsigned char *dst = dst2;
+
+	for (i = 0; i < blkcnt; i++, blk_start++, dst += MMC_BLOCK_SIZE) {
+		r += MMC_BLOCK_SIZE;
+		if (mmc_spi_read_mmc_block(&msdev, dst, blk_start * MMC_BLOCK_SIZE) != RVAL_OK)
+			printf("error in mmc_block_read\n");;
+	}
+	debug("mmc_block_read: %d bytes\n", r);
+	return blkcnt;
+}
+
+static struct spi_slave *slave;
+
+static void spi_assert(void)
+{
+	spi_cs_activate(slave);
+}
+
+static void spi_deassert(void)
+{
+	spi_cs_deactivate(slave);
+}
+
+static int spi_wait_write(unsigned char *buffer, unsigned int count, void *dummy)
+{
+	spi_xfer(slave, count * 8, buffer, NULL, 0);
+	return count;
+}
+
+static int spi_wait_read(unsigned char *buffer, unsigned int count, void *dummy)
+{
+	spi_xfer(slave, count * 8, NULL, buffer, 0);
+	return count;
+}
+
+static int spi_mmc_init(void)
+{
+	char *s;
+	int bus, cs, hz, mode;
+
+	if (slave) {
+		spi_release_bus(slave);
+		spi_free_slave(slave);
+	}
+
+	if ((s = getenv("mmc_bus")))
+		bus = simple_strtoul(s, NULL, 10);
+	else
+		bus = CONFIG_SPI_MMC_DEFAULT_BUS;
+
+	if ((s = getenv("mmc_cs")))
+		cs = simple_strtoul(s, NULL, 10);
+	else
+		cs = CONFIG_SPI_MMC_DEFAULT_CS;
+
+	if ((s = getenv("mmc_hz")))
+		hz = simple_strtoul(s, NULL, 10);
+	else
+		hz = CONFIG_SPI_MMC_DEFAULT_SPEED;
+
+	if ((s = getenv("mmc_mode")))
+		mode = simple_strtoul(s, NULL, 10);
+	else
+		mode = CONFIG_SPI_MMC_DEFAULT_MODE;
+
+	printf("using spi0.%i at %i hz with mode %x\n", cs, hz, mode);
+	slave = spi_setup_slave(bus, cs, hz, mode);
+	if (!slave)
+		return -1;
+	spi_claim_bus(slave);
+
+	return 0;
+}
+
+int mmc_legacy_init(int verbose)
+{
+	int ret;
+
+	ret = spi_mmc_init();
+	if (ret)
+		return ret;
+	msdev.read = &spi_wait_read;
+	msdev.write = &spi_wait_write;
+	msdev.doassert = &spi_assert;
+	msdev.deassert = &spi_deassert;
+	ret = mmc_spi_init_card(&msdev);
+	if (ret)
+		return ret;
+	mmc_block_dev_desc.if_type = IF_TYPE_MMC;
+	mmc_block_dev_desc.part_type = PART_TYPE_DOS;
+	mmc_block_dev_desc.dev = 0;
+	mmc_block_dev_desc.blksz = MMC_BLOCK_SIZE;
+	mmc_block_dev_desc.block_read = mmc_block_read;
+	sprintf(mmc_block_dev_desc.vendor, "Rubico AB <www.rubico.se>");
+	init_part(&mmc_block_dev_desc);
+	return 0;
+}