drivers/spi/kirkwood_spi.c - platform/external/u-boot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * (C) Copyright 2009
  * Marvell Semiconductor <www.marvell.com>
  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
  *
  * Derived from drivers/spi/mpc8xxx_spi.c
  */

 #include <common.h>
 #include <dm.h>
 #include <log.h>
 #include <malloc.h>
 #include <spi.h>
 #include <asm/io.h>
 #include <asm/arch/soc.h>
 #ifdef CONFIG_ARCH_KIRKWOOD
 #include <asm/arch/mpp.h>
 #endif
 #include <asm/arch-mvebu/spi.h>

 static void _spi_cs_activate(struct kwspi_registers *reg)
 {
 	setbits_le32(&reg->ctrl, KWSPI_CSN_ACT);
 }

 static void _spi_cs_deactivate(struct kwspi_registers *reg)
 {
 	clrbits_le32(&reg->ctrl, KWSPI_CSN_ACT);
 }

 static int _spi_xfer(struct kwspi_registers *reg, unsigned int bitlen,
 		     const void *dout, void *din, unsigned long flags)
 {
 	unsigned int tmpdout, tmpdin;
 	int tm, isread = 0;

 	debug("spi_xfer: dout %p din %p bitlen %u\n", dout, din, bitlen);

 	if (flags & SPI_XFER_BEGIN)
 		_spi_cs_activate(reg);

 	/*
 	 * handle data in 8-bit chunks
 	 * TBD: 2byte xfer mode to be enabled
 	 */
 	clrsetbits_le32(&reg->cfg, KWSPI_XFERLEN_MASK, KWSPI_XFERLEN_1BYTE);

 	while (bitlen > 4) {
 		debug("loopstart bitlen %d\n", bitlen);
 		tmpdout = 0;

 		/* Shift data so it's msb-justified */
 		if (dout)
 			tmpdout = *(u32 *)dout & 0xff;

 		clrbits_le32(&reg->irq_cause, KWSPI_SMEMRDIRQ);
 		writel(tmpdout, &reg->dout);	/* Write the data out */
 		debug("*** spi_xfer: ... %08x written, bitlen %d\n",
 		      tmpdout, bitlen);

 		/*
 		 * Wait for SPI transmit to get out
 		 * or time out (1 second = 1000 ms)
 		 * The NE event must be read and cleared first
 		 */
 		for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) {
 			if (readl(&reg->irq_cause) & KWSPI_SMEMRDIRQ) {
 				isread = 1;
 				tmpdin = readl(&reg->din);
 				debug("spi_xfer: din %p..%08x read\n",
 				      din, tmpdin);

 				if (din) {
 					*((u8 *)din) = (u8)tmpdin;
 					din += 1;
 				}
 				if (dout)
 					dout += 1;
 				bitlen -= 8;
 			}
 			if (isread)
 				break;
 		}
 		if (tm >= KWSPI_TIMEOUT)
 			printf("*** spi_xfer: Time out during SPI transfer\n");

 		debug("loopend bitlen %d\n", bitlen);
 	}

 	if (flags & SPI_XFER_END)
 		_spi_cs_deactivate(reg);

 	return 0;
 }

 #ifndef CONFIG_DM_SPI

 static struct kwspi_registers *spireg =
 	(struct kwspi_registers *)MVEBU_SPI_BASE;

 #ifdef CONFIG_ARCH_KIRKWOOD
 static u32 cs_spi_mpp_back[2];
 #endif

 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
 				unsigned int max_hz, unsigned int mode)
 {
 	struct spi_slave *slave;
 	u32 data;
 #ifdef CONFIG_ARCH_KIRKWOOD
 	static const u32 kwspi_mpp_config[2][2] = {
 		{ MPP0_SPI_SCn, 0 }, /* if cs == 0 */
 		{ MPP7_SPI_SCn, 0 } /* if cs != 0 */
 	};
 #endif

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

 	slave = spi_alloc_slave_base(bus, cs);
 	if (!slave)
 		return NULL;

 	writel(KWSPI_SMEMRDY, &spireg->ctrl);

 	/* calculate spi clock prescaller using max_hz */
 	data = ((CONFIG_SYS_TCLK / 2) / max_hz) + 0x10;
 	data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data;
 	data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data;

 	/* program spi clock prescaller using max_hz */
 	writel(KWSPI_ADRLEN_3BYTE | data, &spireg->cfg);
 	debug("data = 0x%08x\n", data);

 	writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause);
 	writel(KWSPI_IRQMASK, &spireg->irq_mask);

 #ifdef CONFIG_ARCH_KIRKWOOD
 	/* program mpp registers to select  SPI_CSn */
 	kirkwood_mpp_conf(kwspi_mpp_config[cs ? 1 : 0], cs_spi_mpp_back);
 #endif

 	return slave;
 }

 void spi_free_slave(struct spi_slave *slave)
 {
 #ifdef CONFIG_ARCH_KIRKWOOD
 	kirkwood_mpp_conf(cs_spi_mpp_back, NULL);
 #endif
 	free(slave);
 }

 __attribute__((weak)) int board_spi_claim_bus(struct spi_slave *slave)
 {
 	return 0;
 }

 int spi_claim_bus(struct spi_slave *slave)
 {
 	return board_spi_claim_bus(slave);
 }

 __attribute__((weak)) void board_spi_release_bus(struct spi_slave *slave)
 {
 }

 void spi_release_bus(struct spi_slave *slave)
 {
 	board_spi_release_bus(slave);
 }

 #ifndef CONFIG_SPI_CS_IS_VALID
 /*
  * you can define this function board specific
  * define above CONFIG in board specific config file and
  * provide the function in board specific src file
  */
 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
 {
 	return bus == 0 && (cs == 0 || cs == 1);
 }
 #endif

 void spi_init(void)
 {
 }

 void spi_cs_activate(struct spi_slave *slave)
 {
 	_spi_cs_activate(spireg);
 }

 void spi_cs_deactivate(struct spi_slave *slave)
 {
 	_spi_cs_deactivate(spireg);
 }

 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
 	     const void *dout, void *din, unsigned long flags)
 {
 	return _spi_xfer(spireg, bitlen, dout, din, flags);
 }

 #else

 /* Here now the DM part */

 struct mvebu_spi_dev {
 	bool			is_errata_50mhz_ac;
 };

 struct mvebu_spi_platdata {
 	struct kwspi_registers *spireg;
 	bool is_errata_50mhz_ac;
 };

 struct mvebu_spi_priv {
 	struct kwspi_registers *spireg;
 };

 static int mvebu_spi_set_speed(struct udevice *bus, uint hz)
 {
 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
 	struct kwspi_registers *reg = plat->spireg;
 	u32 data;

 	/* calculate spi clock prescaller using max_hz */
 	data = ((CONFIG_SYS_TCLK / 2) / hz) + 0x10;
 	data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data;
 	data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data;

 	/* program spi clock prescaler using max_hz */
 	writel(KWSPI_ADRLEN_3BYTE | data, &reg->cfg);
 	debug("data = 0x%08x\n", data);

 	return 0;
 }

 static void mvebu_spi_50mhz_ac_timing_erratum(struct udevice *bus, uint mode)
 {
 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
 	struct kwspi_registers *reg = plat->spireg;
 	u32 data;

 	/*
 	 * Erratum description: (Erratum NO. FE-9144572) The device
 	 * SPI interface supports frequencies of up to 50 MHz.
 	 * However, due to this erratum, when the device core clock is
 	 * 250 MHz and the SPI interfaces is configured for 50MHz SPI
 	 * clock and CPOL=CPHA=1 there might occur data corruption on
 	 * reads from the SPI device.
 	 * Erratum Workaround:
 	 * Work in one of the following configurations:
 	 * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
 	 * Register".
 	 * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
 	 * Register" before setting the interface.
 	 */
 	data = readl(&reg->timing1);
 	data &= ~KW_SPI_TMISO_SAMPLE_MASK;

 	if (CONFIG_SYS_TCLK == 250000000 &&
 	    mode & SPI_CPOL &&
 	    mode & SPI_CPHA)
 		data |= KW_SPI_TMISO_SAMPLE_2;
 	else
 		data |= KW_SPI_TMISO_SAMPLE_1;

 	writel(data, &reg->timing1);
 }

 static int mvebu_spi_set_mode(struct udevice *bus, uint mode)
 {
 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
 	struct kwspi_registers *reg = plat->spireg;
 	u32 data = readl(&reg->cfg);

 	data &= ~(KWSPI_CPHA | KWSPI_CPOL | KWSPI_RXLSBF | KWSPI_TXLSBF);

 	if (mode & SPI_CPHA)
 		data |= KWSPI_CPHA;
 	if (mode & SPI_CPOL)
 		data |= KWSPI_CPOL;
 	if (mode & SPI_LSB_FIRST)
 		data |= (KWSPI_RXLSBF | KWSPI_TXLSBF);

 	writel(data, &reg->cfg);

 	if (plat->is_errata_50mhz_ac)
 		mvebu_spi_50mhz_ac_timing_erratum(bus, mode);

 	return 0;
 }

 static int mvebu_spi_xfer(struct udevice *dev, unsigned int bitlen,
 			  const void *dout, void *din, unsigned long flags)
 {
 	struct udevice *bus = dev->parent;
 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);

 	return _spi_xfer(plat->spireg, bitlen, dout, din, flags);
 }

 __attribute__((weak)) int mvebu_board_spi_claim_bus(struct udevice *dev)
 {
 	return 0;
 }

 static int mvebu_spi_claim_bus(struct udevice *dev)
 {
 	struct udevice *bus = dev->parent;
 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);

 	/* Configure the chip-select in the CTRL register */
 	clrsetbits_le32(&plat->spireg->ctrl,
 			KWSPI_CS_MASK << KWSPI_CS_SHIFT,
 			spi_chip_select(dev) << KWSPI_CS_SHIFT);

 	return mvebu_board_spi_claim_bus(dev);
 }

 __attribute__((weak)) int mvebu_board_spi_release_bus(struct udevice *dev)
 {
 	return 0;
 }

 static int mvebu_spi_release_bus(struct udevice *dev)
 {
 	return mvebu_board_spi_release_bus(dev);
 }

 static int mvebu_spi_probe(struct udevice *bus)
 {
 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
 	struct kwspi_registers *reg = plat->spireg;

 	writel(KWSPI_SMEMRDY, &reg->ctrl);
 	writel(KWSPI_SMEMRDIRQ, &reg->irq_cause);
 	writel(KWSPI_IRQMASK, &reg->irq_mask);

 	return 0;
 }

 static int mvebu_spi_ofdata_to_platdata(struct udevice *bus)
 {
 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
 	const struct mvebu_spi_dev *drvdata =
 		(struct mvebu_spi_dev *)dev_get_driver_data(bus);

 	plat->spireg = (struct kwspi_registers *)devfdt_get_addr(bus);
 	plat->is_errata_50mhz_ac = drvdata->is_errata_50mhz_ac;

 	return 0;
 }

 static const struct dm_spi_ops mvebu_spi_ops = {
 	.claim_bus	= mvebu_spi_claim_bus,
 	.release_bus	= mvebu_spi_release_bus,
 	.xfer		= mvebu_spi_xfer,
 	.set_speed	= mvebu_spi_set_speed,
 	.set_mode	= mvebu_spi_set_mode,
 	/*
 	 * cs_info is not needed, since we require all chip selects to be
 	 * in the device tree explicitly
 	 */
 };

 static const struct mvebu_spi_dev armada_spi_dev_data = {
 	.is_errata_50mhz_ac = false,
 };

 static const struct mvebu_spi_dev armada_xp_spi_dev_data = {
 	.is_errata_50mhz_ac = false,
 };

 static const struct mvebu_spi_dev armada_375_spi_dev_data = {
 	.is_errata_50mhz_ac = false,
 };

 static const struct mvebu_spi_dev armada_380_spi_dev_data = {
 	.is_errata_50mhz_ac = true,
 };

 static const struct udevice_id mvebu_spi_ids[] = {
 	{
 		.compatible = "marvell,orion-spi",
 		.data = (ulong)&armada_spi_dev_data,
 	},
 	{
 		.compatible = "marvell,armada-375-spi",
 		.data = (ulong)&armada_375_spi_dev_data
 	},
 	{
 		.compatible = "marvell,armada-380-spi",
 		.data = (ulong)&armada_380_spi_dev_data
 	},
 	{
 		.compatible = "marvell,armada-xp-spi",
 		.data = (ulong)&armada_xp_spi_dev_data
 	},
 	{ }
 };

 U_BOOT_DRIVER(mvebu_spi) = {
 	.name = "mvebu_spi",
 	.id = UCLASS_SPI,
 	.of_match = mvebu_spi_ids,
 	.ops = &mvebu_spi_ops,
 	.ofdata_to_platdata = mvebu_spi_ofdata_to_platdata,
 	.platdata_auto_alloc_size = sizeof(struct mvebu_spi_platdata),
 	.priv_auto_alloc_size = sizeof(struct mvebu_spi_priv),
 	.probe = mvebu_spi_probe,
 };
 #endif
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* (C) Copyright 2009
	* Marvell Semiconductor <www.marvell.com>
	* Written-by: Prafulla Wadaskar <prafulla@marvell.com>
	*
	* Derived from drivers/spi/mpc8xxx_spi.c
	*/

	#include <common.h>
	#include <dm.h>
	#include <log.h>
	#include <malloc.h>
	#include <spi.h>
	#include <asm/io.h>
	#include <asm/arch/soc.h>
	#ifdef CONFIG_ARCH_KIRKWOOD
	#include <asm/arch/mpp.h>
	#endif
	#include <asm/arch-mvebu/spi.h>

	static void _spi_cs_activate(struct kwspi_registers *reg)
	{
	setbits_le32(&reg->ctrl, KWSPI_CSN_ACT);
	}

	static void _spi_cs_deactivate(struct kwspi_registers *reg)
	{
	clrbits_le32(&reg->ctrl, KWSPI_CSN_ACT);
	}

	static int _spi_xfer(struct kwspi_registers *reg, unsigned int bitlen,
	const void dout, void din, unsigned long flags)
	{
	unsigned int tmpdout, tmpdin;
	int tm, isread = 0;

	debug("spi_xfer: dout %p din %p bitlen %u\n", dout, din, bitlen);

	if (flags & SPI_XFER_BEGIN)
	_spi_cs_activate(reg);

	/*
	* handle data in 8-bit chunks
	* TBD: 2byte xfer mode to be enabled
	*/
	clrsetbits_le32(&reg->cfg, KWSPI_XFERLEN_MASK, KWSPI_XFERLEN_1BYTE);

	while (bitlen > 4) {
	debug("loopstart bitlen %d\n", bitlen);
	tmpdout = 0;

	/* Shift data so it's msb-justified */
	if (dout)
	tmpdout = (u32 )dout & 0xff;

	clrbits_le32(&reg->irq_cause, KWSPI_SMEMRDIRQ);
	writel(tmpdout, &reg->dout); /* Write the data out */
	debug("*** spi_xfer: ... %08x written, bitlen %d\n",
	tmpdout, bitlen);

	/*
	* Wait for SPI transmit to get out
	* or time out (1 second = 1000 ms)
	* The NE event must be read and cleared first
	*/
	for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) {
	if (readl(&reg->irq_cause) & KWSPI_SMEMRDIRQ) {
	isread = 1;
	tmpdin = readl(&reg->din);
	debug("spi_xfer: din %p..%08x read\n",
	din, tmpdin);

	if (din) {
	((u8 )din) = (u8)tmpdin;
	din += 1;
	}
	if (dout)
	dout += 1;
	bitlen -= 8;
	}
	if (isread)
	break;
	}
	if (tm >= KWSPI_TIMEOUT)
	printf("*** spi_xfer: Time out during SPI transfer\n");

	debug("loopend bitlen %d\n", bitlen);
	}

	if (flags & SPI_XFER_END)
	_spi_cs_deactivate(reg);

	return 0;
	}

	#ifndef CONFIG_DM_SPI

	static struct kwspi_registers *spireg =
	(struct kwspi_registers *)MVEBU_SPI_BASE;

	#ifdef CONFIG_ARCH_KIRKWOOD
	static u32 cs_spi_mpp_back[2];
	#endif

	struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
	unsigned int max_hz, unsigned int mode)
	{
	struct spi_slave *slave;
	u32 data;
	#ifdef CONFIG_ARCH_KIRKWOOD
	static const u32 kwspi_mpp_config[2][2] = {
	{ MPP0_SPI_SCn, 0 }, /* if cs == 0 */
	{ MPP7_SPI_SCn, 0 } /* if cs != 0 */
	};
	#endif

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

	slave = spi_alloc_slave_base(bus, cs);
	if (!slave)
	return NULL;

	writel(KWSPI_SMEMRDY, &spireg->ctrl);

	/* calculate spi clock prescaller using max_hz */
	data = ((CONFIG_SYS_TCLK / 2) / max_hz) + 0x10;
	data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data;
	data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data;

	/* program spi clock prescaller using max_hz */
	writel(KWSPI_ADRLEN_3BYTE \| data, &spireg->cfg);
	debug("data = 0x%08x\n", data);

	writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause);
	writel(KWSPI_IRQMASK, &spireg->irq_mask);

	#ifdef CONFIG_ARCH_KIRKWOOD
	/* program mpp registers to select SPI_CSn */
	kirkwood_mpp_conf(kwspi_mpp_config[cs ? 1 : 0], cs_spi_mpp_back);
	#endif

	return slave;
	}

	void spi_free_slave(struct spi_slave *slave)
	{
	#ifdef CONFIG_ARCH_KIRKWOOD
	kirkwood_mpp_conf(cs_spi_mpp_back, NULL);
	#endif
	free(slave);
	}

	__attribute__((weak)) int board_spi_claim_bus(struct spi_slave *slave)
	{
	return 0;
	}

	int spi_claim_bus(struct spi_slave *slave)
	{
	return board_spi_claim_bus(slave);
	}

	__attribute__((weak)) void board_spi_release_bus(struct spi_slave *slave)
	{
	}

	void spi_release_bus(struct spi_slave *slave)
	{
	board_spi_release_bus(slave);
	}

	#ifndef CONFIG_SPI_CS_IS_VALID
	/*
	* you can define this function board specific
	* define above CONFIG in board specific config file and
	* provide the function in board specific src file
	*/
	int spi_cs_is_valid(unsigned int bus, unsigned int cs)
	{
	return bus == 0 && (cs == 0 \|\| cs == 1);
	}
	#endif

	void spi_init(void)
	{
	}

	void spi_cs_activate(struct spi_slave *slave)
	{
	_spi_cs_activate(spireg);
	}

	void spi_cs_deactivate(struct spi_slave *slave)
	{
	_spi_cs_deactivate(spireg);
	}

	int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
	const void dout, void din, unsigned long flags)
	{
	return _spi_xfer(spireg, bitlen, dout, din, flags);
	}

	#else

	/* Here now the DM part */

	struct mvebu_spi_dev {
	bool is_errata_50mhz_ac;
	};

	struct mvebu_spi_platdata {
	struct kwspi_registers *spireg;
	bool is_errata_50mhz_ac;
	};

	struct mvebu_spi_priv {
	struct kwspi_registers *spireg;
	};

	static int mvebu_spi_set_speed(struct udevice *bus, uint hz)
	{
	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
	struct kwspi_registers *reg = plat->spireg;
	u32 data;

	/* calculate spi clock prescaller using max_hz */
	data = ((CONFIG_SYS_TCLK / 2) / hz) + 0x10;
	data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data;
	data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data;

	/* program spi clock prescaler using max_hz */
	writel(KWSPI_ADRLEN_3BYTE \| data, &reg->cfg);
	debug("data = 0x%08x\n", data);

	return 0;
	}

	static void mvebu_spi_50mhz_ac_timing_erratum(struct udevice *bus, uint mode)
	{
	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
	struct kwspi_registers *reg = plat->spireg;
	u32 data;

	/*
	* Erratum description: (Erratum NO. FE-9144572) The device
	* SPI interface supports frequencies of up to 50 MHz.
	* However, due to this erratum, when the device core clock is
	* 250 MHz and the SPI interfaces is configured for 50MHz SPI
	* clock and CPOL=CPHA=1 there might occur data corruption on
	* reads from the SPI device.
	* Erratum Workaround:
	* Work in one of the following configurations:
	* 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
	* Register".
	* 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
	* Register" before setting the interface.
	*/
	data = readl(&reg->timing1);
	data &= ~KW_SPI_TMISO_SAMPLE_MASK;

	if (CONFIG_SYS_TCLK == 250000000 &&
	mode & SPI_CPOL &&
	mode & SPI_CPHA)
	data \|= KW_SPI_TMISO_SAMPLE_2;
	else
	data \|= KW_SPI_TMISO_SAMPLE_1;

	writel(data, &reg->timing1);
	}

	static int mvebu_spi_set_mode(struct udevice *bus, uint mode)
	{
	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
	struct kwspi_registers *reg = plat->spireg;
	u32 data = readl(&reg->cfg);

	data &= ~(KWSPI_CPHA \| KWSPI_CPOL \| KWSPI_RXLSBF \| KWSPI_TXLSBF);

	if (mode & SPI_CPHA)
	data \|= KWSPI_CPHA;
	if (mode & SPI_CPOL)
	data \|= KWSPI_CPOL;
	if (mode & SPI_LSB_FIRST)
	data \|= (KWSPI_RXLSBF \| KWSPI_TXLSBF);

	writel(data, &reg->cfg);

	if (plat->is_errata_50mhz_ac)
	mvebu_spi_50mhz_ac_timing_erratum(bus, mode);

	return 0;
	}

	static int mvebu_spi_xfer(struct udevice *dev, unsigned int bitlen,
	const void dout, void din, unsigned long flags)
	{
	struct udevice *bus = dev->parent;
	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);

	return _spi_xfer(plat->spireg, bitlen, dout, din, flags);
	}

	__attribute__((weak)) int mvebu_board_spi_claim_bus(struct udevice *dev)
	{
	return 0;
	}

	static int mvebu_spi_claim_bus(struct udevice *dev)
	{
	struct udevice *bus = dev->parent;
	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);

	/* Configure the chip-select in the CTRL register */
	clrsetbits_le32(&plat->spireg->ctrl,
	KWSPI_CS_MASK << KWSPI_CS_SHIFT,
	spi_chip_select(dev) << KWSPI_CS_SHIFT);

	return mvebu_board_spi_claim_bus(dev);
	}

	__attribute__((weak)) int mvebu_board_spi_release_bus(struct udevice *dev)
	{
	return 0;
	}

	static int mvebu_spi_release_bus(struct udevice *dev)
	{
	return mvebu_board_spi_release_bus(dev);
	}

	static int mvebu_spi_probe(struct udevice *bus)
	{
	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
	struct kwspi_registers *reg = plat->spireg;

	writel(KWSPI_SMEMRDY, &reg->ctrl);
	writel(KWSPI_SMEMRDIRQ, &reg->irq_cause);
	writel(KWSPI_IRQMASK, &reg->irq_mask);

	return 0;
	}

	static int mvebu_spi_ofdata_to_platdata(struct udevice *bus)
	{
	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
	const struct mvebu_spi_dev *drvdata =
	(struct mvebu_spi_dev *)dev_get_driver_data(bus);

	plat->spireg = (struct kwspi_registers *)devfdt_get_addr(bus);
	plat->is_errata_50mhz_ac = drvdata->is_errata_50mhz_ac;

	return 0;
	}

	static const struct dm_spi_ops mvebu_spi_ops = {
	.claim_bus = mvebu_spi_claim_bus,
	.release_bus = mvebu_spi_release_bus,
	.xfer = mvebu_spi_xfer,
	.set_speed = mvebu_spi_set_speed,
	.set_mode = mvebu_spi_set_mode,
	/*
	* cs_info is not needed, since we require all chip selects to be
	* in the device tree explicitly
	*/
	};

	static const struct mvebu_spi_dev armada_spi_dev_data = {
	.is_errata_50mhz_ac = false,
	};

	static const struct mvebu_spi_dev armada_xp_spi_dev_data = {
	.is_errata_50mhz_ac = false,
	};

	static const struct mvebu_spi_dev armada_375_spi_dev_data = {
	.is_errata_50mhz_ac = false,
	};

	static const struct mvebu_spi_dev armada_380_spi_dev_data = {
	.is_errata_50mhz_ac = true,
	};

	static const struct udevice_id mvebu_spi_ids[] = {
	{
	.compatible = "marvell,orion-spi",
	.data = (ulong)&armada_spi_dev_data,
	},
	{
	.compatible = "marvell,armada-375-spi",
	.data = (ulong)&armada_375_spi_dev_data
	},
	{
	.compatible = "marvell,armada-380-spi",
	.data = (ulong)&armada_380_spi_dev_data
	},
	{
	.compatible = "marvell,armada-xp-spi",
	.data = (ulong)&armada_xp_spi_dev_data
	},
	{ }
	};

	U_BOOT_DRIVER(mvebu_spi) = {
	.name = "mvebu_spi",
	.id = UCLASS_SPI,
	.of_match = mvebu_spi_ids,
	.ops = &mvebu_spi_ops,
	.ofdata_to_platdata = mvebu_spi_ofdata_to_platdata,
	.platdata_auto_alloc_size = sizeof(struct mvebu_spi_platdata),
	.priv_auto_alloc_size = sizeof(struct mvebu_spi_priv),
	.probe = mvebu_spi_probe,
	};
	#endif