drivers/spi/cf_qspi.c - uboot/armada - Git at Google

 /*
  * Freescale Coldfire Queued SPI driver
  *
  * NOTE:
  * This driver is written to transfer 8 bit at-a-time and uses the dedicated
  * SPI slave select pins as bit-banged GPIO to work with spi_flash subsystem.
  *
  *
  * Copyright (C) 2011 Ruggedcom, Inc.
  * Richard Retanubun (richardretanubun@freescale.com)
  *
  * 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 <spi.h>
 #include <asm/immap.h>
 #include <asm/io.h>

 DECLARE_GLOBAL_DATA_PTR;

 #define clamp(x, low, high) (min(max(low, x), high))
 #define to_cf_qspi_slave(s) container_of(s, struct cf_qspi_slave, s)

 struct cf_qspi_slave {
 	struct spi_slave slave;	/* Specific bus:cs ID for each device */
 	qspi_t *regs;		/* Pointer to SPI controller registers */
 	u16 qmr;		/* QMR: Queued Mode Register */
 	u16 qwr;		/* QWR: Queued Wrap Register */
 	u16 qcr;		/* QCR: Queued Command Ram */
 };

 /* Register write wrapper functions */
 static void write_qmr(volatile qspi_t *qspi, u16 val)   { qspi->mr = val; }
 static void write_qdlyr(volatile qspi_t *qspi, u16 val) { qspi->dlyr = val; }
 static void write_qwr(volatile qspi_t *qspi, u16 val)   { qspi->wr = val; }
 static void write_qir(volatile qspi_t *qspi, u16 val)   { qspi->ir = val; }
 static void write_qar(volatile qspi_t *qspi, u16 val)   { qspi->ar = val; }
 static void write_qdr(volatile qspi_t *qspi, u16 val)   { qspi->dr = val; }
 /* Register read wrapper functions */
 static u16 read_qdlyr(volatile qspi_t *qspi) { return qspi->dlyr; }
 static u16 read_qwr(volatile qspi_t *qspi)   { return qspi->wr; }
 static u16 read_qir(volatile qspi_t *qspi)   { return qspi->ir; }
 static u16 read_qdr(volatile qspi_t *qspi)   { return qspi->dr; }

 /* These call points may be different for each ColdFire CPU */
 extern void cfspi_port_conf(void);
 static void cfspi_cs_activate(uint bus, uint cs, uint cs_active_high);
 static void cfspi_cs_deactivate(uint bus, uint cs, uint cs_active_high);

 int spi_claim_bus(struct spi_slave *slave)
 {
 	return 0;
 }
 void spi_release_bus(struct spi_slave *slave)
 {
 }

 __attribute__((weak))
 void spi_init(void)
 {
 	cfspi_port_conf();
 }

 __attribute__((weak))
 void spi_cs_activate(struct spi_slave *slave)
 {
 	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);

 	cfspi_cs_activate(slave->bus, slave->cs, !(dev->qwr & QSPI_QWR_CSIV));
 }

 __attribute__((weak))
 void spi_cs_deactivate(struct spi_slave *slave)
 {
 	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);

 	cfspi_cs_deactivate(slave->bus, slave->cs, !(dev->qwr & QSPI_QWR_CSIV));
 }

 __attribute__((weak))
 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
 {
 	/* Only 1 bus and 4 chipselect per controller */
 	if (bus == 0 && (cs >= 0 && cs < 4))
 		return 1;
 	else
 		return 0;
 }

 void spi_free_slave(struct spi_slave *slave)
 {
 	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);

 	free(dev);
 }

 /* Translate information given by spi_setup_slave to members of cf_qspi_slave */
 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
 				  unsigned int max_hz, unsigned int mode)
 {
 	struct cf_qspi_slave *dev = NULL;

 	if (!spi_cs_is_valid(bus, cs))
 		return NULL;

 	dev = malloc(sizeof(struct cf_qspi_slave));
 	if (!dev)
 		return NULL;

 	/* Initialize to known value */
 	dev->slave.bus = bus;
 	dev->slave.cs  = cs;
 	dev->regs      = (qspi_t *)MMAP_QSPI;
 	dev->qmr       = 0;
 	dev->qwr       = 0;
 	dev->qcr       = 0;


 	/* Map max_hz to QMR[BAUD] */
 	if (max_hz == 0) /* Go as fast as possible */
 		dev->qmr = 2u;
 	else /* Get the closest baud rate */
 		dev->qmr = clamp(((gd->bus_clk >> 2) + max_hz - 1)/max_hz,
 					2u, 255u);

 	/* Map mode to QMR[CPOL] and QMR[CPHA] */
 	if (mode & SPI_CPOL)
 		dev->qmr |= QSPI_QMR_CPOL;

 	if (mode & SPI_CPHA)
 		dev->qmr |= QSPI_QMR_CPHA;

 	/* Hardcode bit length to 8 bit per transter */
 	dev->qmr |= QSPI_QMR_BITS_8;

 	/* Set QMR[MSTR] to enable QSPI as master */
 	dev->qmr |= QSPI_QMR_MSTR;

 	/*
 	 * Set QCR and QWR to default values for spi flash operation.
 	 * If more custom QCR and QRW are needed, overload mode variable
 	 */
 	dev->qcr = (QSPI_QDR_CONT | QSPI_QDR_BITSE);

 	if (!(mode & SPI_CS_HIGH))
 		dev->qwr |= QSPI_QWR_CSIV;

 	return &dev->slave;
 }

 /* Transfer 8 bit at a time */
 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
 	     void *din, unsigned long flags)
 {
 	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);
 	volatile qspi_t *qspi = dev->regs;
 	u8 *txbuf = (u8 *)dout;
 	u8 *rxbuf = (u8 *)din;
 	u32 count = ((bitlen / 8) + (bitlen % 8 ? 1 : 0));
 	u32 n, i = 0;

 	/* Sanitize arguments */
 	if (slave == NULL) {
 		printf("%s: NULL slave ptr\n", __func__);
 		return -1;
 	}

 	if (flags & SPI_XFER_BEGIN)
 		spi_cs_activate(slave);

 	/* There is something to send, lets process it. spi_xfer is also called
 	 * just to toggle chip select, so bitlen of 0 is valid */
 	if (count > 0) {
 		/*
 		* NOTE: Since chip select is driven as a bit-bang-ed GPIO
 		* using spi_cs_activate() and spi_cs_deactivate(),
 		* the chip select settings inside the controller
 		* (i.e. QCR[CONT] and QWR[CSIV]) are moot. The bits are set to
 		* keep the controller settings consistent with the actual
 		* operation of the bus.
 		*/

 		/* Write the slave device's settings for the controller.*/
 		write_qmr(qspi, dev->qmr);
 		write_qwr(qspi, dev->qwr);

 		/* Limit transfer to 16 at a time */
 		n = min(count, 16u);
 		do {
 			/* Setup queue end point */
 			write_qwr(qspi, ((read_qwr(qspi) & QSPI_QWR_ENDQP_MASK)
 				| QSPI_QWR_ENDQP((n-1))));

 			/* Write Command RAM */
 			write_qar(qspi, QSPI_QAR_CMD);
 			for (i = 0; i < n; ++i)
 				write_qdr(qspi, dev->qcr);

 			/* Write TxBuf, if none given, fill with ZEROes */
 			write_qar(qspi, QSPI_QAR_TRANS);
 			if (txbuf) {
 				for (i = 0; i < n; ++i)
 					write_qdr(qspi, *txbuf++);
 			} else {
 				for (i = 0; i < n; ++i)
 					write_qdr(qspi, 0);
 			}

 			/* Clear QIR[SPIF] by writing a 1 to it */
 			write_qir(qspi, read_qir(qspi) | QSPI_QIR_SPIF);
 			/* Set QDLYR[SPE] to start sending */
 			write_qdlyr(qspi, read_qdlyr(qspi) | QSPI_QDLYR_SPE);

 			/* Poll QIR[SPIF] for transfer completion */
 			while ((read_qir(qspi) & QSPI_QIR_SPIF) != 1)
 				udelay(1);

 			/* If given read RxBuf, load data to it */
 			if (rxbuf) {
 				write_qar(qspi, QSPI_QAR_RECV);
 				for (i = 0; i < n; ++i)
 					*rxbuf++ = read_qdr(qspi);
 			}

 			/* Decrement count */
 			count -= n;
 		} while (count);
 	}

 	if (flags & SPI_XFER_END)
 		spi_cs_deactivate(slave);

 	return 0;
 }

 /* Each MCF CPU may have different pin assignments for chip selects. */
 #if defined(CONFIG_M5271)
 /* Assert chip select, val = [1|0] , dir = out, mode = GPIO */
 void cfspi_cs_activate(uint bus, uint cs, uint cs_active_high)
 {
 	debug("%s: bus %d cs %d cs_active_high %d\n",
 		__func__, bus, cs, cs_active_high);

 	switch (cs) {
 	case 0: /* QSPI_CS[0] = PQSPI[3] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x08);
 		else
 			mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xF7);

 		mbar_writeByte(MCF_GPIO_PDDR_QSPI,
 			mbar_readByte(MCF_GPIO_PDDR_QSPI) | 0x08);

 		mbar_writeByte(MCF_GPIO_PAR_QSPI,
 			mbar_readByte(MCF_GPIO_PAR_QSPI) & 0xDF);
 		break;
 	case 1: /* QSPI_CS[1] = PQSPI[4] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x10);
 		else
 			mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xEF);

 		mbar_writeByte(MCF_GPIO_PDDR_QSPI,
 			mbar_readByte(MCF_GPIO_PDDR_QSPI) | 0x10);

 		mbar_writeByte(MCF_GPIO_PAR_QSPI,
 			mbar_readByte(MCF_GPIO_PAR_QSPI) & 0x3F);
 		break;
 	case 2: /* QSPI_CS[2] = PTIMER[7] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x80);
 		else
 			mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0x7F);

 		mbar_writeByte(MCF_GPIO_PDDR_TIMER,
 			mbar_readByte(MCF_GPIO_PDDR_TIMER) | 0x80);

 		mbar_writeShort(MCF_GPIO_PAR_TIMER,
 			mbar_readShort(MCF_GPIO_PAR_TIMER) & 0x3FFF);
 		break;
 	case 3: /* QSPI_CS[3] = PTIMER[3] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x08);
 		else
 			mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0xF7);

 		mbar_writeByte(MCF_GPIO_PDDR_TIMER,
 			mbar_readByte(MCF_GPIO_PDDR_TIMER) | 0x08);

 		mbar_writeShort(MCF_GPIO_PAR_TIMER,
 			mbar_readShort(MCF_GPIO_PAR_TIMER) & 0xFF3F);
 		break;
 	}
 }

 /* Deassert chip select, val = [1|0], dir = in, mode = GPIO
  * direction set as IN to undrive the pin, external pullup/pulldown will bring
  * bus to deassert state.
  */
 void cfspi_cs_deactivate(uint bus, uint cs, uint cs_active_high)
 {
 	debug("%s: bus %d cs %d cs_active_high %d\n",
 		__func__, bus, cs, cs_active_high);

 	switch (cs) {
 	case 0: /* QSPI_CS[0] = PQSPI[3] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xF7);
 		else
 			mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x08);

 		mbar_writeByte(MCF_GPIO_PDDR_QSPI,
 			mbar_readByte(MCF_GPIO_PDDR_QSPI) & 0xF7);

 		mbar_writeByte(MCF_GPIO_PAR_QSPI,
 			mbar_readByte(MCF_GPIO_PAR_QSPI) & 0xDF);
 		break;
 	case 1: /* QSPI_CS[1] = PQSPI[4] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xEF);
 		else
 			mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x10);

 		mbar_writeByte(MCF_GPIO_PDDR_QSPI,
 			mbar_readByte(MCF_GPIO_PDDR_QSPI) & 0xEF);

 		mbar_writeByte(MCF_GPIO_PAR_QSPI,
 			mbar_readByte(MCF_GPIO_PAR_QSPI) & 0x3F);
 		break;
 	case 2: /* QSPI_CS[2] = PTIMER[7] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0x7F);
 		else
 			mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x80);

 		mbar_writeByte(MCF_GPIO_PDDR_TIMER,
 			mbar_readByte(MCF_GPIO_PDDR_TIMER) & 0x7F);

 		mbar_writeShort(MCF_GPIO_PAR_TIMER,
 			mbar_readShort(MCF_GPIO_PAR_TIMER) & 0x3FFF);
 		break;
 	case 3: /* QSPI_CS[3] = PTIMER[3] */
 		if (cs_active_high)
 			mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0xF7);
 		else
 			mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x08);

 		mbar_writeByte(MCF_GPIO_PDDR_TIMER,
 			mbar_readByte(MCF_GPIO_PDDR_TIMER) & 0xF7);

 		mbar_writeShort(MCF_GPIO_PAR_TIMER,
 			mbar_readShort(MCF_GPIO_PAR_TIMER) & 0xFF3F);
 		break;
 	}
 }
 #endif /* CONFIG_M5271 */
	/*
	* Freescale Coldfire Queued SPI driver
	*
	* NOTE:
	* This driver is written to transfer 8 bit at-a-time and uses the dedicated
	* SPI slave select pins as bit-banged GPIO to work with spi_flash subsystem.
	*
	*
	* Copyright (C) 2011 Ruggedcom, Inc.
	* Richard Retanubun (richardretanubun@freescale.com)
	*
	* 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 <spi.h>
	#include <asm/immap.h>
	#include <asm/io.h>

	DECLARE_GLOBAL_DATA_PTR;

	#define clamp(x, low, high) (min(max(low, x), high))
	#define to_cf_qspi_slave(s) container_of(s, struct cf_qspi_slave, s)

	struct cf_qspi_slave {
	struct spi_slave slave; /* Specific bus:cs ID for each device */
	qspi_t regs; / Pointer to SPI controller registers */
	u16 qmr; /* QMR: Queued Mode Register */
	u16 qwr; /* QWR: Queued Wrap Register */
	u16 qcr; /* QCR: Queued Command Ram */
	};

	/* Register write wrapper functions */
	static void write_qmr(volatile qspi_t *qspi, u16 val) { qspi->mr = val; }
	static void write_qdlyr(volatile qspi_t *qspi, u16 val) { qspi->dlyr = val; }
	static void write_qwr(volatile qspi_t *qspi, u16 val) { qspi->wr = val; }
	static void write_qir(volatile qspi_t *qspi, u16 val) { qspi->ir = val; }
	static void write_qar(volatile qspi_t *qspi, u16 val) { qspi->ar = val; }
	static void write_qdr(volatile qspi_t *qspi, u16 val) { qspi->dr = val; }
	/* Register read wrapper functions */
	static u16 read_qdlyr(volatile qspi_t *qspi) { return qspi->dlyr; }
	static u16 read_qwr(volatile qspi_t *qspi) { return qspi->wr; }
	static u16 read_qir(volatile qspi_t *qspi) { return qspi->ir; }
	static u16 read_qdr(volatile qspi_t *qspi) { return qspi->dr; }

	/* These call points may be different for each ColdFire CPU */
	extern void cfspi_port_conf(void);
	static void cfspi_cs_activate(uint bus, uint cs, uint cs_active_high);
	static void cfspi_cs_deactivate(uint bus, uint cs, uint cs_active_high);

	int spi_claim_bus(struct spi_slave *slave)
	{
	return 0;
	}
	void spi_release_bus(struct spi_slave *slave)
	{
	}

	__attribute__((weak))
	void spi_init(void)
	{
	cfspi_port_conf();
	}

	__attribute__((weak))
	void spi_cs_activate(struct spi_slave *slave)
	{
	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);

	cfspi_cs_activate(slave->bus, slave->cs, !(dev->qwr & QSPI_QWR_CSIV));
	}

	__attribute__((weak))
	void spi_cs_deactivate(struct spi_slave *slave)
	{
	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);

	cfspi_cs_deactivate(slave->bus, slave->cs, !(dev->qwr & QSPI_QWR_CSIV));
	}

	__attribute__((weak))
	int spi_cs_is_valid(unsigned int bus, unsigned int cs)
	{
	/* Only 1 bus and 4 chipselect per controller */
	if (bus == 0 && (cs >= 0 && cs < 4))
	return 1;
	else
	return 0;
	}

	void spi_free_slave(struct spi_slave *slave)
	{
	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);

	free(dev);
	}

	/* Translate information given by spi_setup_slave to members of cf_qspi_slave */
	struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
	unsigned int max_hz, unsigned int mode)
	{
	struct cf_qspi_slave *dev = NULL;

	if (!spi_cs_is_valid(bus, cs))
	return NULL;

	dev = malloc(sizeof(struct cf_qspi_slave));
	if (!dev)
	return NULL;

	/* Initialize to known value */
	dev->slave.bus = bus;
	dev->slave.cs = cs;
	dev->regs = (qspi_t *)MMAP_QSPI;
	dev->qmr = 0;
	dev->qwr = 0;
	dev->qcr = 0;


	/* Map max_hz to QMR[BAUD] */
	if (max_hz == 0) /* Go as fast as possible */
	dev->qmr = 2u;
	else /* Get the closest baud rate */
	dev->qmr = clamp(((gd->bus_clk >> 2) + max_hz - 1)/max_hz,
	2u, 255u);

	/* Map mode to QMR[CPOL] and QMR[CPHA] */
	if (mode & SPI_CPOL)
	dev->qmr \|= QSPI_QMR_CPOL;

	if (mode & SPI_CPHA)
	dev->qmr \|= QSPI_QMR_CPHA;

	/* Hardcode bit length to 8 bit per transter */
	dev->qmr \|= QSPI_QMR_BITS_8;

	/* Set QMR[MSTR] to enable QSPI as master */
	dev->qmr \|= QSPI_QMR_MSTR;

	/*
	* Set QCR and QWR to default values for spi flash operation.
	* If more custom QCR and QRW are needed, overload mode variable
	*/
	dev->qcr = (QSPI_QDR_CONT \| QSPI_QDR_BITSE);

	if (!(mode & SPI_CS_HIGH))
	dev->qwr \|= QSPI_QWR_CSIV;

	return &dev->slave;
	}

	/* Transfer 8 bit at a time */
	int spi_xfer(struct spi_slave slave, unsigned int bitlen, const void dout,
	void *din, unsigned long flags)
	{
	struct cf_qspi_slave *dev = to_cf_qspi_slave(slave);
	volatile qspi_t *qspi = dev->regs;
	u8 txbuf = (u8 )dout;
	u8 rxbuf = (u8 )din;
	u32 count = ((bitlen / 8) + (bitlen % 8 ? 1 : 0));
	u32 n, i = 0;

	/* Sanitize arguments */
	if (slave == NULL) {
	printf("%s: NULL slave ptr\n", __func__);
	return -1;
	}

	if (flags & SPI_XFER_BEGIN)
	spi_cs_activate(slave);

	/* There is something to send, lets process it. spi_xfer is also called
	* just to toggle chip select, so bitlen of 0 is valid */
	if (count > 0) {
	/*
	* NOTE: Since chip select is driven as a bit-bang-ed GPIO
	* using spi_cs_activate() and spi_cs_deactivate(),
	* the chip select settings inside the controller
	* (i.e. QCR[CONT] and QWR[CSIV]) are moot. The bits are set to
	* keep the controller settings consistent with the actual
	* operation of the bus.
	*/

	/* Write the slave device's settings for the controller.*/
	write_qmr(qspi, dev->qmr);
	write_qwr(qspi, dev->qwr);

	/* Limit transfer to 16 at a time */
	n = min(count, 16u);
	do {
	/* Setup queue end point */
	write_qwr(qspi, ((read_qwr(qspi) & QSPI_QWR_ENDQP_MASK)
	\| QSPI_QWR_ENDQP((n-1))));

	/* Write Command RAM */
	write_qar(qspi, QSPI_QAR_CMD);
	for (i = 0; i < n; ++i)
	write_qdr(qspi, dev->qcr);

	/* Write TxBuf, if none given, fill with ZEROes */
	write_qar(qspi, QSPI_QAR_TRANS);
	if (txbuf) {
	for (i = 0; i < n; ++i)
	write_qdr(qspi, *txbuf++);
	} else {
	for (i = 0; i < n; ++i)
	write_qdr(qspi, 0);
	}

	/* Clear QIR[SPIF] by writing a 1 to it */
	write_qir(qspi, read_qir(qspi) \| QSPI_QIR_SPIF);
	/* Set QDLYR[SPE] to start sending */
	write_qdlyr(qspi, read_qdlyr(qspi) \| QSPI_QDLYR_SPE);

	/* Poll QIR[SPIF] for transfer completion */
	while ((read_qir(qspi) & QSPI_QIR_SPIF) != 1)
	udelay(1);

	/* If given read RxBuf, load data to it */
	if (rxbuf) {
	write_qar(qspi, QSPI_QAR_RECV);
	for (i = 0; i < n; ++i)
	*rxbuf++ = read_qdr(qspi);
	}

	/* Decrement count */
	count -= n;
	} while (count);
	}

	if (flags & SPI_XFER_END)
	spi_cs_deactivate(slave);

	return 0;
	}

	/* Each MCF CPU may have different pin assignments for chip selects. */
	#if defined(CONFIG_M5271)
	/* Assert chip select, val = [1\|0] , dir = out, mode = GPIO */
	void cfspi_cs_activate(uint bus, uint cs, uint cs_active_high)
	{
	debug("%s: bus %d cs %d cs_active_high %d\n",
	__func__, bus, cs, cs_active_high);

	switch (cs) {
	case 0: /* QSPI_CS[0] = PQSPI[3] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x08);
	else
	mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xF7);

	mbar_writeByte(MCF_GPIO_PDDR_QSPI,
	mbar_readByte(MCF_GPIO_PDDR_QSPI) \| 0x08);

	mbar_writeByte(MCF_GPIO_PAR_QSPI,
	mbar_readByte(MCF_GPIO_PAR_QSPI) & 0xDF);
	break;
	case 1: /* QSPI_CS[1] = PQSPI[4] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x10);
	else
	mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xEF);

	mbar_writeByte(MCF_GPIO_PDDR_QSPI,
	mbar_readByte(MCF_GPIO_PDDR_QSPI) \| 0x10);

	mbar_writeByte(MCF_GPIO_PAR_QSPI,
	mbar_readByte(MCF_GPIO_PAR_QSPI) & 0x3F);
	break;
	case 2: /* QSPI_CS[2] = PTIMER[7] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x80);
	else
	mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0x7F);

	mbar_writeByte(MCF_GPIO_PDDR_TIMER,
	mbar_readByte(MCF_GPIO_PDDR_TIMER) \| 0x80);

	mbar_writeShort(MCF_GPIO_PAR_TIMER,
	mbar_readShort(MCF_GPIO_PAR_TIMER) & 0x3FFF);
	break;
	case 3: /* QSPI_CS[3] = PTIMER[3] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x08);
	else
	mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0xF7);

	mbar_writeByte(MCF_GPIO_PDDR_TIMER,
	mbar_readByte(MCF_GPIO_PDDR_TIMER) \| 0x08);

	mbar_writeShort(MCF_GPIO_PAR_TIMER,
	mbar_readShort(MCF_GPIO_PAR_TIMER) & 0xFF3F);
	break;
	}
	}

	/* Deassert chip select, val = [1\|0], dir = in, mode = GPIO
	* direction set as IN to undrive the pin, external pullup/pulldown will bring
	* bus to deassert state.
	*/
	void cfspi_cs_deactivate(uint bus, uint cs, uint cs_active_high)
	{
	debug("%s: bus %d cs %d cs_active_high %d\n",
	__func__, bus, cs, cs_active_high);

	switch (cs) {
	case 0: /* QSPI_CS[0] = PQSPI[3] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xF7);
	else
	mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x08);

	mbar_writeByte(MCF_GPIO_PDDR_QSPI,
	mbar_readByte(MCF_GPIO_PDDR_QSPI) & 0xF7);

	mbar_writeByte(MCF_GPIO_PAR_QSPI,
	mbar_readByte(MCF_GPIO_PAR_QSPI) & 0xDF);
	break;
	case 1: /* QSPI_CS[1] = PQSPI[4] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PCLRR_QSPI, 0xEF);
	else
	mbar_writeByte(MCF_GPIO_PPDSDR_QSPI, 0x10);

	mbar_writeByte(MCF_GPIO_PDDR_QSPI,
	mbar_readByte(MCF_GPIO_PDDR_QSPI) & 0xEF);

	mbar_writeByte(MCF_GPIO_PAR_QSPI,
	mbar_readByte(MCF_GPIO_PAR_QSPI) & 0x3F);
	break;
	case 2: /* QSPI_CS[2] = PTIMER[7] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0x7F);
	else
	mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x80);

	mbar_writeByte(MCF_GPIO_PDDR_TIMER,
	mbar_readByte(MCF_GPIO_PDDR_TIMER) & 0x7F);

	mbar_writeShort(MCF_GPIO_PAR_TIMER,
	mbar_readShort(MCF_GPIO_PAR_TIMER) & 0x3FFF);
	break;
	case 3: /* QSPI_CS[3] = PTIMER[3] */
	if (cs_active_high)
	mbar_writeByte(MCF_GPIO_PCLRR_TIMER, 0xF7);
	else
	mbar_writeByte(MCF_GPIO_PPDSDR_TIMER, 0x08);

	mbar_writeByte(MCF_GPIO_PDDR_TIMER,
	mbar_readByte(MCF_GPIO_PDDR_TIMER) & 0xF7);

	mbar_writeShort(MCF_GPIO_PAR_TIMER,
	mbar_readShort(MCF_GPIO_PAR_TIMER) & 0xFF3F);
	break;
	}
	}
	#endif /* CONFIG_M5271 */