[u-boot.git] / drivers / spi / mxs_spi.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Freescale i.MX28 SPI driver
 *
 * Copyright (C) 2019 DENX Software Engineering
 * Lukasz Majewski, DENX Software Engineering, [email protected]
 *
 * Copyright (C) 2011 Marek Vasut <[email protected]>
 * on behalf of DENX Software Engineering GmbH
 *
 * NOTE: This driver only supports the SPI-controller chipselects,
 *       GPIO driven chipselects are not supported.
 */

#include <common.h>
#include <dm.h>
#include <dt-structs.h>
#include <cpu_func.h>
#include <errno.h>
#include <log.h>
#include <malloc.h>
#include <memalign.h>
#include <spi.h>
#include <asm/cache.h>
#include <linux/bitops.h>
#include <linux/errno.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/imx-regs.h>
#include <asm/arch/sys_proto.h>
#include <asm/mach-imx/dma.h>

#define	MXS_SPI_MAX_TIMEOUT	1000000
#define	MXS_SPI_PORT_OFFSET	0x2000
#define MXS_SSP_CHIPSELECT_MASK		0x00300000
#define MXS_SSP_CHIPSELECT_SHIFT	20

#define MXSSSP_SMALL_TRANSFER	512

/* Base numbers of i.MX2[38] clk for ssp0 IP block */
#define MXS_SSP_IMX23_CLKID_SSP0 33
#define MXS_SSP_IMX28_CLKID_SSP0 46

struct mxs_spi_platdata {
#if CONFIG_IS_ENABLED(OF_PLATDATA)
	struct dtd_fsl_imx23_spi dtplat;
#endif
	s32 frequency;		/* Default clock frequency, -1 for none */
	fdt_addr_t base;        /* SPI IP block base address */
	int num_cs;             /* Number of CSes supported */
	int dma_id;             /* ID of the DMA channel */
	int clk_id;             /* ID of the SSP clock */
};

struct mxs_spi_priv {
	struct mxs_ssp_regs *regs;
	unsigned int dma_channel;
	unsigned int max_freq;
	unsigned int clk_id;
	unsigned int mode;
};

static void mxs_spi_start_xfer(struct mxs_ssp_regs *ssp_regs)
{
	writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_set);
	writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_clr);
}

static void mxs_spi_end_xfer(struct mxs_ssp_regs *ssp_regs)
{
	writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_clr);
	writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_set);
}

static int mxs_spi_xfer_pio(struct mxs_spi_priv *priv,
			    char *data, int length, int write,
			    unsigned long flags)
{
	struct mxs_ssp_regs *ssp_regs = priv->regs;

	if (flags & SPI_XFER_BEGIN)
		mxs_spi_start_xfer(ssp_regs);

	while (length--) {
		/* We transfer 1 byte */
#if defined(CONFIG_MX23)
		writel(SSP_CTRL0_XFER_COUNT_MASK, &ssp_regs->hw_ssp_ctrl0_clr);
		writel(1, &ssp_regs->hw_ssp_ctrl0_set);
#elif defined(CONFIG_MX28)
		writel(1, &ssp_regs->hw_ssp_xfer_size);
#endif

		if ((flags & SPI_XFER_END) && !length)
			mxs_spi_end_xfer(ssp_regs);

		if (write)
			writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_clr);
		else
			writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_set);

		writel(SSP_CTRL0_RUN, &ssp_regs->hw_ssp_ctrl0_set);

		if (mxs_wait_mask_set(&ssp_regs->hw_ssp_ctrl0_reg,
			SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
			printf("MXS SPI: Timeout waiting for start\n");
			return -ETIMEDOUT;
		}

		if (write)
			writel(*data++, &ssp_regs->hw_ssp_data);

		writel(SSP_CTRL0_DATA_XFER, &ssp_regs->hw_ssp_ctrl0_set);

		if (!write) {
			if (mxs_wait_mask_clr(&ssp_regs->hw_ssp_status_reg,
				SSP_STATUS_FIFO_EMPTY, MXS_SPI_MAX_TIMEOUT)) {
				printf("MXS SPI: Timeout waiting for data\n");
				return -ETIMEDOUT;
			}

			*data = readl(&ssp_regs->hw_ssp_data);
			data++;
		}

		if (mxs_wait_mask_clr(&ssp_regs->hw_ssp_ctrl0_reg,
			SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
			printf("MXS SPI: Timeout waiting for finish\n");
			return -ETIMEDOUT;
		}
	}

	return 0;
}

static int mxs_spi_xfer_dma(struct mxs_spi_priv *priv,
			    char *data, int length, int write,
			    unsigned long flags)
{	struct mxs_ssp_regs *ssp_regs = priv->regs;
	const int xfer_max_sz = 0xff00;
	const int desc_count = DIV_ROUND_UP(length, xfer_max_sz) + 1;
	struct mxs_dma_desc *dp;
	uint32_t ctrl0;
	uint32_t cache_data_count;
	const uint32_t dstart = (uint32_t)data;
	int dmach;
	int tl;
	int ret = 0;

#if defined(CONFIG_MX23)
	const int mxs_spi_pio_words = 1;
#elif defined(CONFIG_MX28)
	const int mxs_spi_pio_words = 4;
#endif

	ALLOC_CACHE_ALIGN_BUFFER(struct mxs_dma_desc, desc, desc_count);

	memset(desc, 0, sizeof(struct mxs_dma_desc) * desc_count);

	ctrl0 = readl(&ssp_regs->hw_ssp_ctrl0);
	ctrl0 |= SSP_CTRL0_DATA_XFER;

	if (flags & SPI_XFER_BEGIN)
		ctrl0 |= SSP_CTRL0_LOCK_CS;
	if (!write)
		ctrl0 |= SSP_CTRL0_READ;

	if (length % ARCH_DMA_MINALIGN)
		cache_data_count = roundup(length, ARCH_DMA_MINALIGN);
	else
		cache_data_count = length;

	/* Flush data to DRAM so DMA can pick them up */
	if (write)
		flush_dcache_range(dstart, dstart + cache_data_count);

	/* Invalidate the area, so no writeback into the RAM races with DMA */
	invalidate_dcache_range(dstart, dstart + cache_data_count);

	dmach = priv->dma_channel;

	dp = desc;
	while (length) {
		dp->address = (dma_addr_t)dp;
		dp->cmd.address = (dma_addr_t)data;

		/*
		 * This is correct, even though it does indeed look insane.
		 * I hereby have to, wholeheartedly, thank Freescale Inc.,
		 * for always inventing insane hardware and keeping me busy
		 * and employed ;-)
		 */
		if (write)
			dp->cmd.data = MXS_DMA_DESC_COMMAND_DMA_READ;
		else
			dp->cmd.data = MXS_DMA_DESC_COMMAND_DMA_WRITE;

		/*
		 * The DMA controller can transfer large chunks (64kB) at
		 * time by setting the transfer length to 0. Setting tl to
		 * 0x10000 will overflow below and make .data contain 0.
		 * Otherwise, 0xff00 is the transfer maximum.
		 */
		if (length >= 0x10000)
			tl = 0x10000;
		else
			tl = min(length, xfer_max_sz);

		dp->cmd.data |=
			((tl & 0xffff) << MXS_DMA_DESC_BYTES_OFFSET) |
			(mxs_spi_pio_words << MXS_DMA_DESC_PIO_WORDS_OFFSET) |
			MXS_DMA_DESC_HALT_ON_TERMINATE |
			MXS_DMA_DESC_TERMINATE_FLUSH;

		data += tl;
		length -= tl;

		if (!length) {
			dp->cmd.data |= MXS_DMA_DESC_IRQ | MXS_DMA_DESC_DEC_SEM;

			if (flags & SPI_XFER_END) {
				ctrl0 &= ~SSP_CTRL0_LOCK_CS;
				ctrl0 |= SSP_CTRL0_IGNORE_CRC;
			}
		}

		/*
		 * Write CTRL0, CMD0, CMD1 and XFER_SIZE registers in
		 * case of MX28, write only CTRL0 in case of MX23 due
		 * to the difference in register layout. It is utterly
		 * essential that the XFER_SIZE register is written on
		 * a per-descriptor basis with the same size as is the
		 * descriptor!
		 */
		dp->cmd.pio_words[0] = ctrl0;
#ifdef CONFIG_MX28
		dp->cmd.pio_words[1] = 0;
		dp->cmd.pio_words[2] = 0;
		dp->cmd.pio_words[3] = tl;
#endif

		mxs_dma_desc_append(dmach, dp);

		dp++;
	}

	if (mxs_dma_go(dmach))
		ret = -EINVAL;

	/* The data arrived into DRAM, invalidate cache over them */
	if (!write)
		invalidate_dcache_range(dstart, dstart + cache_data_count);

	return ret;
}

int mxs_spi_xfer(struct udevice *dev, unsigned int bitlen,
		 const void *dout, void *din, unsigned long flags)
{
	struct udevice *bus = dev_get_parent(dev);
	struct mxs_spi_priv *priv = dev_get_priv(bus);
	struct mxs_ssp_regs *ssp_regs = priv->regs;
	int len = bitlen / 8;
	char dummy;
	int write = 0;
	char *data = NULL;
	int dma = 1;

	if (bitlen == 0) {
		if (flags & SPI_XFER_END) {
			din = (void *)&dummy;
			len = 1;
		} else
			return 0;
	}

	/* Half-duplex only */
	if (din && dout)
		return -EINVAL;
	/* No data */
	if (!din && !dout)
		return 0;

	if (dout) {
		data = (char *)dout;
		write = 1;
	} else if (din) {
		data = (char *)din;
		write = 0;
	}

	/*
	 * Check for alignment, if the buffer is aligned, do DMA transfer,
	 * PIO otherwise. This is a temporary workaround until proper bounce
	 * buffer is in place.
	 */
	if (dma) {
		if (((uint32_t)data) & (ARCH_DMA_MINALIGN - 1))
			dma = 0;
		if (((uint32_t)len) & (ARCH_DMA_MINALIGN - 1))
			dma = 0;
	}

	if (!dma || (len < MXSSSP_SMALL_TRANSFER)) {
		writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_clr);
		return mxs_spi_xfer_pio(priv, data, len, write, flags);
	} else {
		writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_set);
		return mxs_spi_xfer_dma(priv, data, len, write, flags);
	}
}

static int mxs_spi_probe(struct udevice *bus)
{
	struct mxs_spi_platdata *plat = dev_get_plat(bus);
	struct mxs_spi_priv *priv = dev_get_priv(bus);
	int ret;

	debug("%s: probe\n", __func__);

#if CONFIG_IS_ENABLED(OF_PLATDATA)
	struct dtd_fsl_imx23_spi *dtplat = &plat->dtplat;
	struct phandle_1_arg *p1a = &dtplat->clocks[0];

	priv->regs = (struct mxs_ssp_regs *)dtplat->reg[0];
	priv->dma_channel = dtplat->dmas[1];
	priv->clk_id = p1a->arg[0];
	priv->max_freq = dtplat->spi_max_frequency;
	plat->num_cs = dtplat->num_cs;

	debug("OF_PLATDATA: regs: 0x%x max freq: %d clkid: %d\n",
	      (unsigned int)priv->regs, priv->max_freq, priv->clk_id);
#else
	priv->regs = (struct mxs_ssp_regs *)plat->base;
	priv->max_freq = plat->frequency;

	priv->dma_channel = plat->dma_id;
	priv->clk_id = plat->clk_id;
#endif

	mxs_reset_block(&priv->regs->hw_ssp_ctrl0_reg);

	ret = mxs_dma_init_channel(priv->dma_channel);
	if (ret) {
		printf("%s: DMA init channel error %d\n", __func__, ret);
		return ret;
	}

	return 0;
}

static int mxs_spi_claim_bus(struct udevice *dev)
{
	struct udevice *bus = dev_get_parent(dev);
	struct mxs_spi_priv *priv = dev_get_priv(bus);
	struct mxs_ssp_regs *ssp_regs = priv->regs;
	int cs = spi_chip_select(dev);

	/*
	 * i.MX28 supports up to 3 CS (SSn0, SSn1, SSn2)
	 * To set them it uses following tuple (WAIT_FOR_IRQ,WAIT_FOR_CMD),
	 * where:
	 *
	 * WAIT_FOR_IRQ is bit 21 of HW_SSP_CTRL0
	 * WAIT_FOR_CMD is bit 20 (#defined as MXS_SSP_CHIPSELECT_SHIFT here) of
	 *                        HW_SSP_CTRL0
	 * SSn0 b00
	 * SSn1 b01
	 * SSn2 b10 (which require setting WAIT_FOR_IRQ)
	 *
	 * However, for now i.MX28 SPI driver will support up till 2 CSes
	 * (SSn0, and SSn1).
	 */

	/* Ungate SSP clock and set active CS */
	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl0,
			BIT(MXS_SSP_CHIPSELECT_SHIFT) |
			SSP_CTRL0_CLKGATE, (cs << MXS_SSP_CHIPSELECT_SHIFT));

	return 0;
}

static int mxs_spi_release_bus(struct udevice *dev)
{
	struct udevice *bus = dev_get_parent(dev);
	struct mxs_spi_priv *priv = dev_get_priv(bus);
	struct mxs_ssp_regs *ssp_regs = priv->regs;

	/* Gate SSP clock */
	setbits_le32(&ssp_regs->hw_ssp_ctrl0, SSP_CTRL0_CLKGATE);

	return 0;
}

static int mxs_spi_set_speed(struct udevice *bus, uint speed)
{
	struct mxs_spi_priv *priv = dev_get_priv(bus);
#ifdef CONFIG_MX28
	int clkid = priv->clk_id - MXS_SSP_IMX28_CLKID_SSP0;
#else /* CONFIG_MX23 */
	int clkid = priv->clk_id - MXS_SSP_IMX23_CLKID_SSP0;
#endif
	if (speed > priv->max_freq)
		speed = priv->max_freq;

	debug("%s speed: %u [Hz] clkid: %d\n", __func__, speed, clkid);
	mxs_set_ssp_busclock(clkid, speed / 1000);

	return 0;
}

static int mxs_spi_set_mode(struct udevice *bus, uint mode)
{
	struct mxs_spi_priv *priv = dev_get_priv(bus);
	struct mxs_ssp_regs *ssp_regs = priv->regs;
	u32 reg;

	priv->mode = mode;
	debug("%s: mode 0x%x\n", __func__, mode);

	reg = SSP_CTRL1_SSP_MODE_SPI | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS;
	reg |= (priv->mode & SPI_CPOL) ? SSP_CTRL1_POLARITY : 0;
	reg |= (priv->mode & SPI_CPHA) ? SSP_CTRL1_PHASE : 0;
	writel(reg, &ssp_regs->hw_ssp_ctrl1);

	/* Single bit SPI support */
	writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT, &ssp_regs->hw_ssp_ctrl0);

	return 0;
}

static const struct dm_spi_ops mxs_spi_ops = {
	.claim_bus	= mxs_spi_claim_bus,
	.release_bus    = mxs_spi_release_bus,
	.xfer		= mxs_spi_xfer,
	.set_speed	= mxs_spi_set_speed,
	.set_mode	= mxs_spi_set_mode,
	/*
	 * cs_info is not needed, since we require all chip selects to be
	 * in the device tree explicitly
	 */
};

#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
static int mxs_of_to_plat(struct udevice *bus)
{
	struct mxs_spi_platdata *plat = bus->plat;
	u32 prop[2];
	int ret;

	plat->base = dev_read_addr(bus);
	plat->frequency =
		dev_read_u32_default(bus, "spi-max-frequency", 40000000);
	plat->num_cs = dev_read_u32_default(bus, "num-cs", 2);

	ret = dev_read_u32_array(bus, "dmas", prop, ARRAY_SIZE(prop));
	if (ret) {
		printf("%s: Reading 'dmas' property failed!\n", __func__);
		return ret;
	}
	plat->dma_id = prop[1];

	ret = dev_read_u32_array(bus, "clocks", prop, ARRAY_SIZE(prop));
	if (ret) {
		printf("%s: Reading 'clocks' property failed!\n", __func__);
		return ret;
	}
	plat->clk_id = prop[1];

	debug("%s: base=0x%x, max-frequency=%d num-cs=%d dma_id=%d clk_id=%d\n",
	      __func__, (uint)plat->base, plat->frequency, plat->num_cs,
	      plat->dma_id, plat->clk_id);

	return 0;
}

static const struct udevice_id mxs_spi_ids[] = {
	{ .compatible = "fsl,imx23-spi" },
	{ .compatible = "fsl,imx28-spi" },
	{ }
};
#endif

U_BOOT_DRIVER(fsl_imx23_spi) = {
	.name = "fsl_imx23_spi",
	.id	= UCLASS_SPI,
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
	.of_match = mxs_spi_ids,
	.of_to_plat = mxs_of_to_plat,
#endif
	.plat_auto	= sizeof(struct mxs_spi_platdata),
	.ops	= &mxs_spi_ops,
	.priv_auto	= sizeof(struct mxs_spi_priv),
	.probe	= mxs_spi_probe,
};

U_BOOT_DRIVER_ALIAS(fsl_imx23_spi, fsl_imx28_spi)
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
ec33de3d MV	2	/*
	3	* Freescale i.MX28 SPI driver
	4	*
d99b018a LM	5	* Copyright (C) 2019 DENX Software Engineering
	6	* Lukasz Majewski, DENX Software Engineering, [email protected]
	7	*
ec33de3d MV	8	* Copyright (C) 2011 Marek Vasut <[email protected]>
	9	* on behalf of DENX Software Engineering GmbH
	10	*
ec33de3d MV	11	* NOTE: This driver only supports the SPI-controller chipselects,
	12	* GPIO driven chipselects are not supported.
	13	*/
	14
	15	#include <common.h>
7e07b372 JT	16	#include <dm.h>
7e07b372 JT	17	#include <dt-structs.h>
1eb69ae4	18	#include <cpu_func.h>
7e07b372	19	#include <errno.h>
f7ae49fc	20	#include <log.h>
ec33de3d	21	#include <malloc.h>
cf92e05c	22	#include <memalign.h>
ec33de3d	23	#include <spi.h>
90526e9f	24	#include <asm/cache.h>
cd93d625	25	#include <linux/bitops.h>
1221ce45	26	#include <linux/errno.h>
ec33de3d MV	27	#include <asm/io.h>
	28	#include <asm/arch/clock.h>
	29	#include <asm/arch/imx-regs.h>
	30	#include <asm/arch/sys_proto.h>
552a848e	31	#include <asm/mach-imx/dma.h>
ec33de3d MV	32
	33	#define MXS_SPI_MAX_TIMEOUT 1000000
	34	#define MXS_SPI_PORT_OFFSET 0x2000
148ca64f FE	35	#define MXS_SSP_CHIPSELECT_MASK 0x00300000
148ca64f FE	36	#define MXS_SSP_CHIPSELECT_SHIFT 20
ec33de3d	37
7c5e6f7a MV	38	#define MXSSSP_SMALL_TRANSFER 512
7c5e6f7a MV	39
7e07b372 JT	40	/* Base numbers of i.MX2[38] clk for ssp0 IP block */
	41	#define MXS_SSP_IMX23_CLKID_SSP0 33
	42	#define MXS_SSP_IMX28_CLKID_SSP0 46
ec0c81f8	43
d99b018a	44	struct mxs_spi_platdata {
ec0c81f8	45	#if CONFIG_IS_ENABLED(OF_PLATDATA)
df17cdc9	46	struct dtd_fsl_imx23_spi dtplat;
ec0c81f8	47	#endif
d99b018a LM	48	s32 frequency; /* Default clock frequency, -1 for none */
	49	fdt_addr_t base; /* SPI IP block base address */
	50	int num_cs; /* Number of CSes supported */
	51	int dma_id; /* ID of the DMA channel */
	52	int clk_id; /* ID of the SSP clock */
	53	};
ec33de3d	54
d99b018a LM	55	struct mxs_spi_priv {
	56	struct mxs_ssp_regs *regs;
	57	unsigned int dma_channel;
	58	unsigned int max_freq;
	59	unsigned int clk_id;
	60	unsigned int mode;
	61	};
ec33de3d	62
7e07b372 JT	63	static void mxs_spi_start_xfer(struct mxs_ssp_regs *ssp_regs)
	64	{
	65	writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_set);
	66	writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_clr);
	67	}
	68
	69	static void mxs_spi_end_xfer(struct mxs_ssp_regs *ssp_regs)
	70	{
	71	writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_clr);
	72	writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_set);
	73	}
	74
d99b018a LM	75	static int mxs_spi_xfer_pio(struct mxs_spi_priv *priv,
	76	char *data, int length, int write,
	77	unsigned long flags)
	78	{
	79	struct mxs_ssp_regs *ssp_regs = priv->regs;
c7065fa8	80
ec33de3d MV	81	if (flags & SPI_XFER_BEGIN)
	82	mxs_spi_start_xfer(ssp_regs);
	83
ccd4d5a0	84	while (length--) {
ec33de3d	85	/* We transfer 1 byte */
c96e78cc MV	86	#if defined(CONFIG_MX23)
	87	writel(SSP_CTRL0_XFER_COUNT_MASK, &ssp_regs->hw_ssp_ctrl0_clr);
	88	writel(1, &ssp_regs->hw_ssp_ctrl0_set);
	89	#elif defined(CONFIG_MX28)
ec33de3d	90	writel(1, &ssp_regs->hw_ssp_xfer_size);
c96e78cc	91	#endif
ec33de3d	92
ccd4d5a0	93	if ((flags & SPI_XFER_END) && !length)
ec33de3d MV	94	mxs_spi_end_xfer(ssp_regs);
ec33de3d MV	95
c7065fa8	96	if (write)
ec33de3d MV	97	writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_clr);
	98	else
	99	writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_set);
	100
	101	writel(SSP_CTRL0_RUN, &ssp_regs->hw_ssp_ctrl0_set);
	102
fa7a51cb	103	if (mxs_wait_mask_set(&ssp_regs->hw_ssp_ctrl0_reg,
ec33de3d MV	104	SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
ec33de3d MV	105	printf("MXS SPI: Timeout waiting for start\n");
d9fb6a4c	106	return -ETIMEDOUT;
ec33de3d MV	107	}
ec33de3d MV	108
c7065fa8 MV	109	if (write)
c7065fa8 MV	110	writel(*data++, &ssp_regs->hw_ssp_data);
ec33de3d MV	111
	112	writel(SSP_CTRL0_DATA_XFER, &ssp_regs->hw_ssp_ctrl0_set);
	113
c7065fa8	114	if (!write) {
fa7a51cb	115	if (mxs_wait_mask_clr(&ssp_regs->hw_ssp_status_reg,
ec33de3d MV	116	SSP_STATUS_FIFO_EMPTY, MXS_SPI_MAX_TIMEOUT)) {
ec33de3d MV	117	printf("MXS SPI: Timeout waiting for data\n");
d9fb6a4c	118	return -ETIMEDOUT;
ec33de3d MV	119	}
ec33de3d MV	120
c7065fa8 MV	121	*data = readl(&ssp_regs->hw_ssp_data);
c7065fa8 MV	122	data++;
ec33de3d MV	123	}
ec33de3d MV	124
fa7a51cb	125	if (mxs_wait_mask_clr(&ssp_regs->hw_ssp_ctrl0_reg,
ec33de3d MV	126	SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
ec33de3d MV	127	printf("MXS SPI: Timeout waiting for finish\n");
d9fb6a4c	128	return -ETIMEDOUT;
ec33de3d MV	129	}
	130	}
	131
	132	return 0;
ccd4d5a0 MV	133	}
ccd4d5a0 MV	134
d99b018a LM	135	static int mxs_spi_xfer_dma(struct mxs_spi_priv *priv,
	136	char *data, int length, int write,
	137	unsigned long flags)
	138	{ struct mxs_ssp_regs *ssp_regs = priv->regs;
2c432144 MV	139	const int xfer_max_sz = 0xff00;
2c432144 MV	140	const int desc_count = DIV_ROUND_UP(length, xfer_max_sz) + 1;
2c432144 MV	141	struct mxs_dma_desc *dp;
2c432144 MV	142	uint32_t ctrl0;
7c5e6f7a	143	uint32_t cache_data_count;
88d15559	144	const uint32_t dstart = (uint32_t)data;
7c5e6f7a	145	int dmach;
2c432144	146	int tl;
e9f7eafd	147	int ret = 0;
2c432144	148
c96e78cc MV	149	#if defined(CONFIG_MX23)
	150	const int mxs_spi_pio_words = 1;
	151	#elif defined(CONFIG_MX28)
	152	const int mxs_spi_pio_words = 4;
	153	#endif
	154
2c432144 MV	155	ALLOC_CACHE_ALIGN_BUFFER(struct mxs_dma_desc, desc, desc_count);
	156
	157	memset(desc, 0, sizeof(struct mxs_dma_desc) * desc_count);
7c5e6f7a	158
2c432144 MV	159	ctrl0 = readl(&ssp_regs->hw_ssp_ctrl0);
2c432144 MV	160	ctrl0 \|= SSP_CTRL0_DATA_XFER;
7c5e6f7a MV	161
	162	if (flags & SPI_XFER_BEGIN)
	163	ctrl0 \|= SSP_CTRL0_LOCK_CS;
7c5e6f7a MV	164	if (!write)
	165	ctrl0 \|= SSP_CTRL0_READ;
	166
7c5e6f7a MV	167	if (length % ARCH_DMA_MINALIGN)
	168	cache_data_count = roundup(length, ARCH_DMA_MINALIGN);
	169	else
	170	cache_data_count = length;
	171
88d15559	172	/* Flush data to DRAM so DMA can pick them up */
2c432144	173	if (write)
88d15559 MV	174	flush_dcache_range(dstart, dstart + cache_data_count);
	175
	176	/* Invalidate the area, so no writeback into the RAM races with DMA */
	177	invalidate_dcache_range(dstart, dstart + cache_data_count);
7c5e6f7a	178
d99b018a	179	dmach = priv->dma_channel;
2c432144 MV	180
	181	dp = desc;
	182	while (length) {
	183	dp->address = (dma_addr_t)dp;
	184	dp->cmd.address = (dma_addr_t)data;
	185
	186	/*
	187	* This is correct, even though it does indeed look insane.
	188	* I hereby have to, wholeheartedly, thank Freescale Inc.,
	189	* for always inventing insane hardware and keeping me busy
	190	* and employed ;-)
	191	*/
	192	if (write)
	193	dp->cmd.data = MXS_DMA_DESC_COMMAND_DMA_READ;
	194	else
	195	dp->cmd.data = MXS_DMA_DESC_COMMAND_DMA_WRITE;
	196
	197	/*
	198	* The DMA controller can transfer large chunks (64kB) at
	199	* time by setting the transfer length to 0. Setting tl to
	200	* 0x10000 will overflow below and make .data contain 0.
	201	* Otherwise, 0xff00 is the transfer maximum.
	202	*/
	203	if (length >= 0x10000)
	204	tl = 0x10000;
	205	else
	206	tl = min(length, xfer_max_sz);
	207
	208	dp->cmd.data \|=
e9f7eafd	209	((tl & 0xffff) << MXS_DMA_DESC_BYTES_OFFSET) \|
c96e78cc	210	(mxs_spi_pio_words << MXS_DMA_DESC_PIO_WORDS_OFFSET) \|
2c432144 MV	211	MXS_DMA_DESC_HALT_ON_TERMINATE \|
2c432144 MV	212	MXS_DMA_DESC_TERMINATE_FLUSH;
7c5e6f7a	213
2c432144 MV	214	data += tl;
	215	length -= tl;
	216
e9f7eafd MV	217	if (!length) {
	218	dp->cmd.data \|= MXS_DMA_DESC_IRQ \| MXS_DMA_DESC_DEC_SEM;
	219
	220	if (flags & SPI_XFER_END) {
	221	ctrl0 &= ~SSP_CTRL0_LOCK_CS;
	222	ctrl0 \|= SSP_CTRL0_IGNORE_CRC;
	223	}
	224	}
	225
	226	/*
c96e78cc MV	227	* Write CTRL0, CMD0, CMD1 and XFER_SIZE registers in
	228	* case of MX28, write only CTRL0 in case of MX23 due
	229	* to the difference in register layout. It is utterly
e9f7eafd MV	230	* essential that the XFER_SIZE register is written on
	231	* a per-descriptor basis with the same size as is the
	232	* descriptor!
	233	*/
	234	dp->cmd.pio_words[0] = ctrl0;
c96e78cc	235	#ifdef CONFIG_MX28
e9f7eafd MV	236	dp->cmd.pio_words[1] = 0;
	237	dp->cmd.pio_words[2] = 0;
	238	dp->cmd.pio_words[3] = tl;
c96e78cc	239	#endif
e9f7eafd	240
2c432144 MV	241	mxs_dma_desc_append(dmach, dp);
	242
	243	dp++;
	244	}
	245
7c5e6f7a	246	if (mxs_dma_go(dmach))
e9f7eafd	247	ret = -EINVAL;
7c5e6f7a MV	248
7c5e6f7a MV	249	/* The data arrived into DRAM, invalidate cache over them */
88d15559 MV	250	if (!write)
88d15559 MV	251	invalidate_dcache_range(dstart, dstart + cache_data_count);
7c5e6f7a	252
e9f7eafd	253	return ret;
7c5e6f7a MV	254	}
7c5e6f7a MV	255
d99b018a LM	256	int mxs_spi_xfer(struct udevice *dev, unsigned int bitlen,
	257	const void dout, void din, unsigned long flags)
	258	{
	259	struct udevice *bus = dev_get_parent(dev);
	260	struct mxs_spi_priv *priv = dev_get_priv(bus);
	261	struct mxs_ssp_regs *ssp_regs = priv->regs;
ccd4d5a0 MV	262	int len = bitlen / 8;
	263	char dummy;
	264	int write = 0;
	265	char *data = NULL;
7c5e6f7a	266	int dma = 1;
7c5e6f7a	267
ccd4d5a0 MV	268	if (bitlen == 0) {
	269	if (flags & SPI_XFER_END) {
	270	din = (void *)&dummy;
	271	len = 1;
	272	} else
	273	return 0;
	274	}
	275
	276	/* Half-duplex only */
	277	if (din && dout)
	278	return -EINVAL;
	279	/* No data */
	280	if (!din && !dout)
	281	return 0;
	282
	283	if (dout) {
	284	data = (char *)dout;
	285	write = 1;
	286	} else if (din) {
	287	data = (char *)din;
	288	write = 0;
	289	}
	290
7c5e6f7a MV	291	/*
	292	* Check for alignment, if the buffer is aligned, do DMA transfer,
	293	* PIO otherwise. This is a temporary workaround until proper bounce
	294	* buffer is in place.
	295	*/
	296	if (dma) {
	297	if (((uint32_t)data) & (ARCH_DMA_MINALIGN - 1))
	298	dma = 0;
	299	if (((uint32_t)len) & (ARCH_DMA_MINALIGN - 1))
	300	dma = 0;
	301	}
	302
	303	if (!dma \|\| (len < MXSSSP_SMALL_TRANSFER)) {
	304	writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_clr);
d99b018a	305	return mxs_spi_xfer_pio(priv, data, len, write, flags);
7c5e6f7a MV	306	} else {
7c5e6f7a MV	307	writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_set);
d99b018a	308	return mxs_spi_xfer_dma(priv, data, len, write, flags);
d99b018a	309	}
d99b018a LM	310	}
d99b018a LM	311
d99b018a LM	312	static int mxs_spi_probe(struct udevice *bus)
d99b018a LM	313	{
c69cda25	314	struct mxs_spi_platdata *plat = dev_get_plat(bus);
d99b018a LM	315	struct mxs_spi_priv *priv = dev_get_priv(bus);
	316	int ret;
	317
	318	debug("%s: probe\n", __func__);
ec0c81f8 LM	319
ec0c81f8 LM	320	#if CONFIG_IS_ENABLED(OF_PLATDATA)
df17cdc9	321	struct dtd_fsl_imx23_spi *dtplat = &plat->dtplat;
ec0c81f8 LM	322	struct phandle_1_arg *p1a = &dtplat->clocks[0];
	323
	324	priv->regs = (struct mxs_ssp_regs *)dtplat->reg[0];
	325	priv->dma_channel = dtplat->dmas[1];
	326	priv->clk_id = p1a->arg[0];
	327	priv->max_freq = dtplat->spi_max_frequency;
	328	plat->num_cs = dtplat->num_cs;
	329
	330	debug("OF_PLATDATA: regs: 0x%x max freq: %d clkid: %d\n",
	331	(unsigned int)priv->regs, priv->max_freq, priv->clk_id);
	332	#else
d99b018a LM	333	priv->regs = (struct mxs_ssp_regs *)plat->base;
	334	priv->max_freq = plat->frequency;
	335
	336	priv->dma_channel = plat->dma_id;
	337	priv->clk_id = plat->clk_id;
ec0c81f8	338	#endif
d99b018a	339
c2050e10 LM	340	mxs_reset_block(&priv->regs->hw_ssp_ctrl0_reg);
c2050e10 LM	341
d99b018a LM	342	ret = mxs_dma_init_channel(priv->dma_channel);
	343	if (ret) {
	344	printf("%s: DMA init channel error %d\n", __func__, ret);
	345	return ret;
	346	}
	347
	348	return 0;
	349	}
	350
	351	static int mxs_spi_claim_bus(struct udevice *dev)
	352	{
	353	struct udevice *bus = dev_get_parent(dev);
	354	struct mxs_spi_priv *priv = dev_get_priv(bus);
	355	struct mxs_ssp_regs *ssp_regs = priv->regs;
	356	int cs = spi_chip_select(dev);
	357
	358	/*
	359	* i.MX28 supports up to 3 CS (SSn0, SSn1, SSn2)
	360	* To set them it uses following tuple (WAIT_FOR_IRQ,WAIT_FOR_CMD),
	361	* where:
	362	*
	363	* WAIT_FOR_IRQ is bit 21 of HW_SSP_CTRL0
	364	* WAIT_FOR_CMD is bit 20 (#defined as MXS_SSP_CHIPSELECT_SHIFT here) of
	365	* HW_SSP_CTRL0
	366	* SSn0 b00
	367	* SSn1 b01
	368	* SSn2 b10 (which require setting WAIT_FOR_IRQ)
	369	*
	370	* However, for now i.MX28 SPI driver will support up till 2 CSes
	371	* (SSn0, and SSn1).
	372	*/
	373
	374	/* Ungate SSP clock and set active CS */
	375	clrsetbits_le32(&ssp_regs->hw_ssp_ctrl0,
	376	BIT(MXS_SSP_CHIPSELECT_SHIFT) \|
	377	SSP_CTRL0_CLKGATE, (cs << MXS_SSP_CHIPSELECT_SHIFT));
	378
	379	return 0;
	380	}
	381
	382	static int mxs_spi_release_bus(struct udevice *dev)
	383	{
	384	struct udevice *bus = dev_get_parent(dev);
	385	struct mxs_spi_priv *priv = dev_get_priv(bus);
	386	struct mxs_ssp_regs *ssp_regs = priv->regs;
	387
	388	/* Gate SSP clock */
	389	setbits_le32(&ssp_regs->hw_ssp_ctrl0, SSP_CTRL0_CLKGATE);
	390
	391	return 0;
	392	}
	393
	394	static int mxs_spi_set_speed(struct udevice *bus, uint speed)
	395	{
	396	struct mxs_spi_priv *priv = dev_get_priv(bus);
	397	#ifdef CONFIG_MX28
	398	int clkid = priv->clk_id - MXS_SSP_IMX28_CLKID_SSP0;
	399	#else /* CONFIG_MX23 */
	400	int clkid = priv->clk_id - MXS_SSP_IMX23_CLKID_SSP0;
	401	#endif
	402	if (speed > priv->max_freq)
	403	speed = priv->max_freq;
	404
	405	debug("%s speed: %u [Hz] clkid: %d\n", __func__, speed, clkid);
406	mxs_set_ssp_busclock(clkid, speed / 1000);
407
408	return 0;
409	}
410
411	static int mxs_spi_set_mode(struct udevice *bus, uint mode)
412	{
413	struct mxs_spi_priv *priv = dev_get_priv(bus);
414	struct mxs_ssp_regs *ssp_regs = priv->regs;
415	u32 reg;
416
417	priv->mode = mode;
418	debug("%s: mode 0x%x\n", __func__, mode);
419
420	reg = SSP_CTRL1_SSP_MODE_SPI \| SSP_CTRL1_WORD_LENGTH_EIGHT_BITS;
421	reg \|= (priv->mode & SPI_CPOL) ? SSP_CTRL1_POLARITY : 0;
422	reg \|= (priv->mode & SPI_CPHA) ? SSP_CTRL1_PHASE : 0;
423	writel(reg, &ssp_regs->hw_ssp_ctrl1);
424
425	/* Single bit SPI support */
426	writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT, &ssp_regs->hw_ssp_ctrl0);
427
428	return 0;
429	}
430
431	static const struct dm_spi_ops mxs_spi_ops = {
432	.claim_bus = mxs_spi_claim_bus,
433	.release_bus = mxs_spi_release_bus,
434	.xfer = mxs_spi_xfer,
435	.set_speed = mxs_spi_set_speed,
436	.set_mode = mxs_spi_set_mode,
437	/*
438	* cs_info is not needed, since we require all chip selects to be
439	* in the device tree explicitly
440	*/
441	};
442
443	#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
d1998a9f	444	static int mxs_of_to_plat(struct udevice *bus)
d99b018a	445	{
caa4daa2	446	struct mxs_spi_platdata *plat = bus->plat;
d99b018a LM	447	u32 prop[2];
	448	int ret;
	449
	450	plat->base = dev_read_addr(bus);
	451	plat->frequency =
	452	dev_read_u32_default(bus, "spi-max-frequency", 40000000);
	453	plat->num_cs = dev_read_u32_default(bus, "num-cs", 2);
	454
	455	ret = dev_read_u32_array(bus, "dmas", prop, ARRAY_SIZE(prop));
	456	if (ret) {
	457	printf("%s: Reading 'dmas' property failed!\n", __func__);
	458	return ret;
	459	}
	460	plat->dma_id = prop[1];
	461
	462	ret = dev_read_u32_array(bus, "clocks", prop, ARRAY_SIZE(prop));
	463	if (ret) {
	464	printf("%s: Reading 'clocks' property failed!\n", __func__);
	465	return ret;
	466	}
	467	plat->clk_id = prop[1];
	468
	469	debug("%s: base=0x%x, max-frequency=%d num-cs=%d dma_id=%d clk_id=%d\n",
	470	__func__, (uint)plat->base, plat->frequency, plat->num_cs,
	471	plat->dma_id, plat->clk_id);
	472
	473	return 0;
	474	}
d99b018a LM	475
	476	static const struct udevice_id mxs_spi_ids[] = {
	477	{ .compatible = "fsl,imx23-spi" },
	478	{ .compatible = "fsl,imx28-spi" },
	479	{ }
	480	};
ec0c81f8	481	#endif
d99b018a	482
e3e2470f	483	U_BOOT_DRIVER(fsl_imx23_spi) = {
ec0c81f8	484	.name = "fsl_imx23_spi",
d99b018a LM	485	.id = UCLASS_SPI,
	486	#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
	487	.of_match = mxs_spi_ids,
d1998a9f	488	.of_to_plat = mxs_of_to_plat,
d99b018a	489	#endif
caa4daa2	490	.plat_auto = sizeof(struct mxs_spi_platdata),
d99b018a	491	.ops = &mxs_spi_ops,
41575d8e	492	.priv_auto = sizeof(struct mxs_spi_priv),
d99b018a LM	493	.probe = mxs_spi_probe,
d99b018a LM	494	};
addf358b WL	495
addf358b WL	496	U_BOOT_DRIVER_ALIAS(fsl_imx23_spi, fsl_imx28_spi)