drivers/spi/atcspi200_spi.c - u-boot-mtk - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Andestech ATCSPI200 SPI controller driver.
  *
  * Copyright 2017 Andes Technology, Inc.
  * Author: Rick Chen (rick@andestech.com)
  */

 #include <common.h>
 #include <clk.h>
 #include <malloc.h>
 #include <spi.h>
 #include <asm/io.h>
 #include <dm.h>

 DECLARE_GLOBAL_DATA_PTR;

 #define MAX_TRANSFER_LEN	512
 #define CHUNK_SIZE		1
 #define SPI_TIMEOUT		0x100000
 #define SPI0_BUS		0
 #define SPI1_BUS		1
 #define SPI0_BASE		0xf0b00000
 #define SPI1_BASE		0xf0f00000
 #define NSPI_MAX_CS_NUM		1

 struct atcspi200_spi_regs {
 	u32	rev;
 	u32	reserve1[3];
 	u32	format;		/* 0x10 */
 #define DATA_LENGTH(x)	((x-1)<<8)
 	u32	pio;
 	u32	reserve2[2];
 	u32	tctrl;		/* 0x20 */
 #define TRAMODE_OFFSET	24
 #define TRAMODE_MASK	(0x0F<<TRAMODE_OFFSET)
 #define TRAMODE_WR_SYNC	(0<<TRAMODE_OFFSET)
 #define TRAMODE_WO	(1<<TRAMODE_OFFSET)
 #define TRAMODE_RO	(2<<TRAMODE_OFFSET)
 #define TRAMODE_WR	(3<<TRAMODE_OFFSET)
 #define TRAMODE_RW	(4<<TRAMODE_OFFSET)
 #define TRAMODE_WDR	(5<<TRAMODE_OFFSET)
 #define TRAMODE_RDW	(6<<TRAMODE_OFFSET)
 #define TRAMODE_NONE	(7<<TRAMODE_OFFSET)
 #define TRAMODE_DW	(8<<TRAMODE_OFFSET)
 #define TRAMODE_DR	(9<<TRAMODE_OFFSET)
 #define WCNT_OFFSET	12
 #define WCNT_MASK	(0x1FF<<WCNT_OFFSET)
 #define RCNT_OFFSET	0
 #define RCNT_MASK	(0x1FF<<RCNT_OFFSET)
 	u32	cmd;
 	u32	addr;
 	u32	data;
 	u32	ctrl;		/* 0x30 */
 #define TXFTH_OFFSET	16
 #define RXFTH_OFFSET	8
 #define TXDMAEN		(1<<4)
 #define RXDMAEN		(1<<3)
 #define TXFRST		(1<<2)
 #define RXFRST		(1<<1)
 #define SPIRST		(1<<0)
 	u32	status;
 #define TXFFL		(1<<23)
 #define TXEPTY		(1<<22)
 #define TXFVE_MASK	(0x1F<<16)
 #define RXFEM		(1<<14)
 #define RXFVE_OFFSET	(8)
 #define RXFVE_MASK	(0x1F<<RXFVE_OFFSET)
 #define SPIBSY		(1<<0)
 	u32	inten;
 	u32	intsta;
 	u32	timing;		/* 0x40 */
 #define SCLK_DIV_MASK	0xFF
 };

 struct nds_spi_slave {
 	volatile struct atcspi200_spi_regs *regs;
 	int		to;
 	unsigned int	freq;
 	ulong		clock;
 	unsigned int	mode;
 	u8 		num_cs;
 	unsigned int	mtiming;
 	size_t		cmd_len;
 	u8		cmd_buf[16];
 	size_t		data_len;
 	size_t		tran_len;
 	u8		*din;
 	u8		*dout;
 	unsigned int    max_transfer_length;
 };

 static int __atcspi200_spi_set_speed(struct nds_spi_slave *ns)
 {
 	u32 tm;
 	u8 div;
 	tm = ns->regs->timing;
 	tm &= ~SCLK_DIV_MASK;

 	if(ns->freq >= ns->clock)
 		div =0xff;
 	else{
 		for (div = 0; div < 0xff; div++) {
 			if (ns->freq >= ns->clock / (2 * (div + 1)))
 				break;
 		}
 	}

 	tm |= div;
 	ns->regs->timing = tm;

 	return 0;

 }

 static int __atcspi200_spi_claim_bus(struct nds_spi_slave *ns)
 {
 		unsigned int format=0;
 		ns->regs->ctrl |= (TXFRST|RXFRST|SPIRST);
 		while((ns->regs->ctrl &(TXFRST|RXFRST|SPIRST))&&(ns->to--))
 			if(!ns->to)
 				return -EINVAL;

 		ns->cmd_len = 0;
 		format = ns->mode|DATA_LENGTH(8);
 		ns->regs->format = format;
 		__atcspi200_spi_set_speed(ns);

 		return 0;
 }

 static int __atcspi200_spi_release_bus(struct nds_spi_slave *ns)
 {
 	/* do nothing */
 	return 0;
 }

 static int __atcspi200_spi_start(struct nds_spi_slave *ns)
 {
 	int i,olen=0;
 	int tc = ns->regs->tctrl;

 	tc &= ~(WCNT_MASK|RCNT_MASK|TRAMODE_MASK);
 	if ((ns->din)&&(ns->cmd_len))
 		tc |= TRAMODE_WR;
 	else if (ns->din)
 		tc |= TRAMODE_RO;
 	else
 		tc |= TRAMODE_WO;

 	if(ns->dout)
 		olen = ns->tran_len;
 	tc |= (ns->cmd_len+olen-1) << WCNT_OFFSET;

 	if(ns->din)
 		tc |= (ns->tran_len-1) << RCNT_OFFSET;

 	ns->regs->tctrl = tc;
 	ns->regs->cmd = 1;

 	for (i=0;i<ns->cmd_len;i++)
 		ns->regs->data = ns->cmd_buf[i];

 	return 0;
 }

 static int __atcspi200_spi_stop(struct nds_spi_slave *ns)
 {
 	ns->regs->timing = ns->mtiming;
 	while ((ns->regs->status & SPIBSY)&&(ns->to--))
 		if (!ns->to)
 			return -EINVAL;

 	return 0;
 }

 static void __nspi_espi_tx(struct nds_spi_slave *ns, const void *dout)
 {
 	ns->regs->data = *(u8 *)dout;
 }

 static int __nspi_espi_rx(struct nds_spi_slave *ns, void *din, unsigned int bytes)
 {
 	*(u8 *)din = ns->regs->data;
 	return bytes;
 }


 static int __atcspi200_spi_xfer(struct nds_spi_slave *ns,
 		unsigned int bitlen,  const void *data_out, void *data_in,
 		unsigned long flags)
 {
 		unsigned int event, rx_bytes;
 		const void *dout = NULL;
 		void *din = NULL;
 		int num_blks, num_chunks, max_tran_len, tran_len;
 		int num_bytes;
 		u8 *cmd_buf = ns->cmd_buf;
 		size_t cmd_len = ns->cmd_len;
 		unsigned long data_len = bitlen / 8;
 		int rf_cnt;
 		int ret = 0;

 		max_tran_len = ns->max_transfer_length;
 		switch (flags) {
 		case SPI_XFER_BEGIN:
 			cmd_len = ns->cmd_len = data_len;
 			memcpy(cmd_buf, data_out, cmd_len);
 			return 0;

 		case 0:
 		case SPI_XFER_END:
 			if (bitlen == 0) {
 				return 0;
 			}
 			ns->data_len = data_len;
 			ns->din = (u8 *)data_in;
 			ns->dout = (u8 *)data_out;
 			break;

 		case SPI_XFER_BEGIN | SPI_XFER_END:
 			ns->data_len = 0;
 			ns->din = 0;
 			ns->dout = 0;
 			cmd_len = ns->cmd_len = data_len;
 			memcpy(cmd_buf, data_out, cmd_len);
 			data_out = 0;
 			data_len = 0;
 			__atcspi200_spi_start(ns);
 			break;
 		}
 		if (data_out)
 			debug("spi_xfer: data_out %08X(%p) data_in %08X(%p) data_len %lu\n",
 			      *(uint *)data_out, data_out, *(uint *)data_in,
 			      data_in, data_len);
 		num_chunks = DIV_ROUND_UP(data_len, max_tran_len);
 		din = data_in;
 		dout = data_out;
 		while (num_chunks--) {
 			tran_len = min((size_t)data_len, (size_t)max_tran_len);
 			ns->tran_len = tran_len;
 			num_blks = DIV_ROUND_UP(tran_len , CHUNK_SIZE);
 			num_bytes = (tran_len) % CHUNK_SIZE;
 			if(num_bytes == 0)
 				num_bytes = CHUNK_SIZE;
 			__atcspi200_spi_start(ns);

 			while (num_blks) {
 				event = in_le32(&ns->regs->status);
 				if ((event & TXEPTY) && (data_out)) {
 					__nspi_espi_tx(ns, dout);
 					num_blks -= CHUNK_SIZE;
 					dout += CHUNK_SIZE;
 				}

 				if ((event & RXFVE_MASK) && (data_in)) {
 					rf_cnt = ((event & RXFVE_MASK)>> RXFVE_OFFSET);
 					if (rf_cnt >= CHUNK_SIZE)
 						rx_bytes = CHUNK_SIZE;
 					else if (num_blks == 1 && rf_cnt == num_bytes)
 						rx_bytes = num_bytes;
 					else
 						continue;

 					if (__nspi_espi_rx(ns, din, rx_bytes) == rx_bytes) {
 						num_blks -= CHUNK_SIZE;
 						din = (unsigned char *)din + rx_bytes;
 					}
 				}
 			}

 			data_len -= tran_len;
 			if(data_len)
 			{
 				ns->cmd_buf[1] += ((tran_len>>16)&0xff);
 				ns->cmd_buf[2] += ((tran_len>>8)&0xff);
 				ns->cmd_buf[3] += ((tran_len)&0xff);
 				ns->data_len = data_len;
 			}
 			ret = __atcspi200_spi_stop(ns);
 		}
 		ret = __atcspi200_spi_stop(ns);

 		return ret;
 }

 static int atcspi200_spi_set_speed(struct udevice *bus, uint max_hz)
 {
 	struct nds_spi_slave *ns = dev_get_priv(bus);

 	debug("%s speed %u\n", __func__, max_hz);

 	ns->freq = max_hz;
 	__atcspi200_spi_set_speed(ns);

 	return 0;
 }

 static int atcspi200_spi_set_mode(struct udevice *bus, uint mode)
 {
 	struct nds_spi_slave *ns = dev_get_priv(bus);

 	debug("%s mode %u\n", __func__, mode);
 	ns->mode = mode;

 	return 0;
 }

 static int atcspi200_spi_claim_bus(struct udevice *dev)
 {
 	struct dm_spi_slave_platdata *slave_plat =
 		dev_get_parent_platdata(dev);
 	struct udevice *bus = dev->parent;
 	struct nds_spi_slave *ns = dev_get_priv(bus);

 	if (slave_plat->cs >= ns->num_cs) {
 		printf("Invalid SPI chipselect\n");
 		return -EINVAL;
 	}

 	return __atcspi200_spi_claim_bus(ns);
 }

 static int atcspi200_spi_release_bus(struct udevice *dev)
 {
 	struct nds_spi_slave *ns = dev_get_priv(dev->parent);

 	return __atcspi200_spi_release_bus(ns);
 }

 static int atcspi200_spi_xfer(struct udevice *dev, unsigned int bitlen,
 			    const void *dout, void *din,
 			    unsigned long flags)
 {
 	struct udevice *bus = dev->parent;
 	struct nds_spi_slave *ns = dev_get_priv(bus);

 	return __atcspi200_spi_xfer(ns, bitlen, dout, din, flags);
 }

 static int atcspi200_spi_get_clk(struct udevice *bus)
 {
 	struct nds_spi_slave *ns = dev_get_priv(bus);
 	struct clk clk;
 	ulong clk_rate;
 	int ret;

 	ret = clk_get_by_index(bus, 0, &clk);
 	if (ret)
 		return -EINVAL;

 	clk_rate = clk_get_rate(&clk);
 	if (!clk_rate)
 		return -EINVAL;

 	ns->clock = clk_rate;
 	clk_free(&clk);

 	return 0;
 }

 static int atcspi200_spi_probe(struct udevice *bus)
 {
 	struct nds_spi_slave *ns = dev_get_priv(bus);

 	ns->to = SPI_TIMEOUT;
 	ns->max_transfer_length = MAX_TRANSFER_LEN;
 	ns->mtiming = ns->regs->timing;
 	atcspi200_spi_get_clk(bus);

 	return 0;
 }

 static int atcspi200_ofdata_to_platadata(struct udevice *bus)
 {
 	struct nds_spi_slave *ns = dev_get_priv(bus);
 	const void *blob = gd->fdt_blob;
 	int node = dev_of_offset(bus);

 	ns->regs = map_physmem(devfdt_get_addr(bus),
 				 sizeof(struct atcspi200_spi_regs),
 				 MAP_NOCACHE);
 	if (!ns->regs) {
 		printf("%s: could not map device address\n", __func__);
 		return -EINVAL;
 	}
 	ns->num_cs = fdtdec_get_int(blob, node, "num-cs", 4);

 	return 0;
 }

 static const struct dm_spi_ops atcspi200_spi_ops = {
 	.claim_bus	= atcspi200_spi_claim_bus,
 	.release_bus	= atcspi200_spi_release_bus,
 	.xfer		= atcspi200_spi_xfer,
 	.set_speed	= atcspi200_spi_set_speed,
 	.set_mode	= atcspi200_spi_set_mode,
 };

 static const struct udevice_id atcspi200_spi_ids[] = {
 	{ .compatible = "andestech,atcspi200" },
 	{ }
 };

 U_BOOT_DRIVER(atcspi200_spi) = {
 	.name = "atcspi200_spi",
 	.id = UCLASS_SPI,
 	.of_match = atcspi200_spi_ids,
 	.ops = &atcspi200_spi_ops,
 	.ofdata_to_platdata = atcspi200_ofdata_to_platadata,
 	.priv_auto_alloc_size = sizeof(struct nds_spi_slave),
 	.probe = atcspi200_spi_probe,
 };
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Andestech ATCSPI200 SPI controller driver.
	*
	* Copyright 2017 Andes Technology, Inc.
	* Author: Rick Chen (rick@andestech.com)
	*/

	#include <common.h>
	#include <clk.h>
	#include <malloc.h>
	#include <spi.h>
	#include <asm/io.h>
	#include <dm.h>

	DECLARE_GLOBAL_DATA_PTR;

	#define MAX_TRANSFER_LEN 512
	#define CHUNK_SIZE 1
	#define SPI_TIMEOUT 0x100000
	#define SPI0_BUS 0
	#define SPI1_BUS 1
	#define SPI0_BASE 0xf0b00000
	#define SPI1_BASE 0xf0f00000
	#define NSPI_MAX_CS_NUM 1

	struct atcspi200_spi_regs {
	u32 rev;
	u32 reserve1[3];
	u32 format; /* 0x10 */
	#define DATA_LENGTH(x) ((x-1)<<8)
	u32 pio;
	u32 reserve2[2];
	u32 tctrl; /* 0x20 */
	#define TRAMODE_OFFSET 24
	#define TRAMODE_MASK (0x0F<<TRAMODE_OFFSET)
	#define TRAMODE_WR_SYNC (0<<TRAMODE_OFFSET)
	#define TRAMODE_WO (1<<TRAMODE_OFFSET)
	#define TRAMODE_RO (2<<TRAMODE_OFFSET)
	#define TRAMODE_WR (3<<TRAMODE_OFFSET)
	#define TRAMODE_RW (4<<TRAMODE_OFFSET)
	#define TRAMODE_WDR (5<<TRAMODE_OFFSET)
	#define TRAMODE_RDW (6<<TRAMODE_OFFSET)
	#define TRAMODE_NONE (7<<TRAMODE_OFFSET)
	#define TRAMODE_DW (8<<TRAMODE_OFFSET)
	#define TRAMODE_DR (9<<TRAMODE_OFFSET)
	#define WCNT_OFFSET 12
	#define WCNT_MASK (0x1FF<<WCNT_OFFSET)
	#define RCNT_OFFSET 0
	#define RCNT_MASK (0x1FF<<RCNT_OFFSET)
	u32 cmd;
	u32 addr;
	u32 data;
	u32 ctrl; /* 0x30 */
	#define TXFTH_OFFSET 16
	#define RXFTH_OFFSET 8
	#define TXDMAEN (1<<4)
	#define RXDMAEN (1<<3)
	#define TXFRST (1<<2)
	#define RXFRST (1<<1)
	#define SPIRST (1<<0)
	u32 status;
	#define TXFFL (1<<23)
	#define TXEPTY (1<<22)
	#define TXFVE_MASK (0x1F<<16)
	#define RXFEM (1<<14)
	#define RXFVE_OFFSET (8)
	#define RXFVE_MASK (0x1F<<RXFVE_OFFSET)
	#define SPIBSY (1<<0)
	u32 inten;
	u32 intsta;
	u32 timing; /* 0x40 */
	#define SCLK_DIV_MASK 0xFF
	};

	struct nds_spi_slave {
	volatile struct atcspi200_spi_regs *regs;
	int to;
	unsigned int freq;
	ulong clock;
	unsigned int mode;
	u8 num_cs;
	unsigned int mtiming;
	size_t cmd_len;
	u8 cmd_buf[16];
	size_t data_len;
	size_t tran_len;
	u8 *din;
	u8 *dout;
	unsigned int max_transfer_length;
	};

	static int __atcspi200_spi_set_speed(struct nds_spi_slave *ns)
	{
	u32 tm;
	u8 div;
	tm = ns->regs->timing;
	tm &= ~SCLK_DIV_MASK;

	if(ns->freq >= ns->clock)
	div =0xff;
	else{
	for (div = 0; div < 0xff; div++) {
	if (ns->freq >= ns->clock / (2 * (div + 1)))
	break;
	}
	}

	tm \|= div;
	ns->regs->timing = tm;

	return 0;

	}

	static int __atcspi200_spi_claim_bus(struct nds_spi_slave *ns)
	{
	unsigned int format=0;
	ns->regs->ctrl \|= (TXFRST\|RXFRST\|SPIRST);
	while((ns->regs->ctrl &(TXFRST\|RXFRST\|SPIRST))&&(ns->to--))
	if(!ns->to)
	return -EINVAL;

	ns->cmd_len = 0;
	format = ns->mode\|DATA_LENGTH(8);
	ns->regs->format = format;
	__atcspi200_spi_set_speed(ns);

	return 0;
	}

	static int __atcspi200_spi_release_bus(struct nds_spi_slave *ns)
	{
	/* do nothing */
	return 0;
	}

	static int __atcspi200_spi_start(struct nds_spi_slave *ns)
	{
	int i,olen=0;
	int tc = ns->regs->tctrl;

	tc &= ~(WCNT_MASK\|RCNT_MASK\|TRAMODE_MASK);
	if ((ns->din)&&(ns->cmd_len))
	tc \|= TRAMODE_WR;
	else if (ns->din)
	tc \|= TRAMODE_RO;
	else
	tc \|= TRAMODE_WO;

	if(ns->dout)
	olen = ns->tran_len;
	tc \|= (ns->cmd_len+olen-1) << WCNT_OFFSET;

	if(ns->din)
	tc \|= (ns->tran_len-1) << RCNT_OFFSET;

	ns->regs->tctrl = tc;
	ns->regs->cmd = 1;

	for (i=0;i<ns->cmd_len;i++)
	ns->regs->data = ns->cmd_buf[i];

	return 0;
	}

	static int __atcspi200_spi_stop(struct nds_spi_slave *ns)
	{
	ns->regs->timing = ns->mtiming;
	while ((ns->regs->status & SPIBSY)&&(ns->to--))
	if (!ns->to)
	return -EINVAL;

	return 0;
	}

	static void __nspi_espi_tx(struct nds_spi_slave ns, const void dout)
	{
	ns->regs->data = (u8 )dout;
	}

	static int __nspi_espi_rx(struct nds_spi_slave ns, void din, unsigned int bytes)
	{
	(u8 )din = ns->regs->data;
	return bytes;
	}


	static int __atcspi200_spi_xfer(struct nds_spi_slave *ns,
	unsigned int bitlen, const void data_out, void data_in,
	unsigned long flags)
	{
	unsigned int event, rx_bytes;
	const void *dout = NULL;
	void *din = NULL;
	int num_blks, num_chunks, max_tran_len, tran_len;
	int num_bytes;
	u8 *cmd_buf = ns->cmd_buf;
	size_t cmd_len = ns->cmd_len;
	unsigned long data_len = bitlen / 8;
	int rf_cnt;
	int ret = 0;

	max_tran_len = ns->max_transfer_length;
	switch (flags) {
	case SPI_XFER_BEGIN:
	cmd_len = ns->cmd_len = data_len;
	memcpy(cmd_buf, data_out, cmd_len);
	return 0;

	case 0:
	case SPI_XFER_END:
	if (bitlen == 0) {
	return 0;
	}
	ns->data_len = data_len;
	ns->din = (u8 *)data_in;
	ns->dout = (u8 *)data_out;
	break;

	case SPI_XFER_BEGIN \| SPI_XFER_END:
	ns->data_len = 0;
	ns->din = 0;
	ns->dout = 0;
	cmd_len = ns->cmd_len = data_len;
	memcpy(cmd_buf, data_out, cmd_len);
	data_out = 0;
	data_len = 0;
	__atcspi200_spi_start(ns);
	break;
	}
	if (data_out)
	debug("spi_xfer: data_out %08X(%p) data_in %08X(%p) data_len %lu\n",
	(uint )data_out, data_out, (uint )data_in,
	data_in, data_len);
	num_chunks = DIV_ROUND_UP(data_len, max_tran_len);
	din = data_in;
	dout = data_out;
	while (num_chunks--) {
	tran_len = min((size_t)data_len, (size_t)max_tran_len);
	ns->tran_len = tran_len;
	num_blks = DIV_ROUND_UP(tran_len , CHUNK_SIZE);
	num_bytes = (tran_len) % CHUNK_SIZE;
	if(num_bytes == 0)
	num_bytes = CHUNK_SIZE;
	__atcspi200_spi_start(ns);

	while (num_blks) {
	event = in_le32(&ns->regs->status);
	if ((event & TXEPTY) && (data_out)) {
	__nspi_espi_tx(ns, dout);
	num_blks -= CHUNK_SIZE;
	dout += CHUNK_SIZE;
	}

	if ((event & RXFVE_MASK) && (data_in)) {
	rf_cnt = ((event & RXFVE_MASK)>> RXFVE_OFFSET);
	if (rf_cnt >= CHUNK_SIZE)
	rx_bytes = CHUNK_SIZE;
	else if (num_blks == 1 && rf_cnt == num_bytes)
	rx_bytes = num_bytes;
	else
	continue;

	if (__nspi_espi_rx(ns, din, rx_bytes) == rx_bytes) {
	num_blks -= CHUNK_SIZE;
	din = (unsigned char *)din + rx_bytes;
	}
	}
	}

	data_len -= tran_len;
	if(data_len)
	{
	ns->cmd_buf[1] += ((tran_len>>16)&0xff);
	ns->cmd_buf[2] += ((tran_len>>8)&0xff);
	ns->cmd_buf[3] += ((tran_len)&0xff);
	ns->data_len = data_len;
	}
	ret = __atcspi200_spi_stop(ns);
	}
	ret = __atcspi200_spi_stop(ns);

	return ret;
	}

	static int atcspi200_spi_set_speed(struct udevice *bus, uint max_hz)
	{
	struct nds_spi_slave *ns = dev_get_priv(bus);

	debug("%s speed %u\n", __func__, max_hz);

	ns->freq = max_hz;
	__atcspi200_spi_set_speed(ns);

	return 0;
	}

	static int atcspi200_spi_set_mode(struct udevice *bus, uint mode)
	{
	struct nds_spi_slave *ns = dev_get_priv(bus);

	debug("%s mode %u\n", __func__, mode);
	ns->mode = mode;

	return 0;
	}

	static int atcspi200_spi_claim_bus(struct udevice *dev)
	{
	struct dm_spi_slave_platdata *slave_plat =
	dev_get_parent_platdata(dev);
	struct udevice *bus = dev->parent;
	struct nds_spi_slave *ns = dev_get_priv(bus);

	if (slave_plat->cs >= ns->num_cs) {
	printf("Invalid SPI chipselect\n");
	return -EINVAL;
	}

	return __atcspi200_spi_claim_bus(ns);
	}

	static int atcspi200_spi_release_bus(struct udevice *dev)
	{
	struct nds_spi_slave *ns = dev_get_priv(dev->parent);

	return __atcspi200_spi_release_bus(ns);
	}

	static int atcspi200_spi_xfer(struct udevice *dev, unsigned int bitlen,
	const void dout, void din,
	unsigned long flags)
	{
	struct udevice *bus = dev->parent;
	struct nds_spi_slave *ns = dev_get_priv(bus);

	return __atcspi200_spi_xfer(ns, bitlen, dout, din, flags);
	}

	static int atcspi200_spi_get_clk(struct udevice *bus)
	{
	struct nds_spi_slave *ns = dev_get_priv(bus);
	struct clk clk;
	ulong clk_rate;
	int ret;

	ret = clk_get_by_index(bus, 0, &clk);
	if (ret)
	return -EINVAL;

	clk_rate = clk_get_rate(&clk);
	if (!clk_rate)
	return -EINVAL;

	ns->clock = clk_rate;
	clk_free(&clk);

	return 0;
	}

	static int atcspi200_spi_probe(struct udevice *bus)
	{
	struct nds_spi_slave *ns = dev_get_priv(bus);

	ns->to = SPI_TIMEOUT;
	ns->max_transfer_length = MAX_TRANSFER_LEN;
	ns->mtiming = ns->regs->timing;
	atcspi200_spi_get_clk(bus);

	return 0;
	}

	static int atcspi200_ofdata_to_platadata(struct udevice *bus)
	{
	struct nds_spi_slave *ns = dev_get_priv(bus);
	const void *blob = gd->fdt_blob;
	int node = dev_of_offset(bus);

	ns->regs = map_physmem(devfdt_get_addr(bus),
	sizeof(struct atcspi200_spi_regs),
	MAP_NOCACHE);
	if (!ns->regs) {
	printf("%s: could not map device address\n", __func__);
	return -EINVAL;
	}
	ns->num_cs = fdtdec_get_int(blob, node, "num-cs", 4);

	return 0;
	}

	static const struct dm_spi_ops atcspi200_spi_ops = {
	.claim_bus = atcspi200_spi_claim_bus,
	.release_bus = atcspi200_spi_release_bus,
	.xfer = atcspi200_spi_xfer,
	.set_speed = atcspi200_spi_set_speed,
	.set_mode = atcspi200_spi_set_mode,
	};

	static const struct udevice_id atcspi200_spi_ids[] = {
	{ .compatible = "andestech,atcspi200" },
	{ }
	};

	U_BOOT_DRIVER(atcspi200_spi) = {
	.name = "atcspi200_spi",
	.id = UCLASS_SPI,
	.of_match = atcspi200_spi_ids,
	.ops = &atcspi200_spi_ops,
	.ofdata_to_platdata = atcspi200_ofdata_to_platadata,
	.priv_auto_alloc_size = sizeof(struct nds_spi_slave),
	.probe = atcspi200_spi_probe,
	};