mtd: add LPC32xx SLC NAND driver

This patch adds support for the SLC NAND controller inside the LPC32xx SoC.

[dwmw2: 21st century pedantry]

Signed-off-by: Roland Stigge <[e-mail]>
Signed-off-by: Artem Bityutskiy <[e-mail]>
Signed-off-by: David Woodhouse <[e-mail]>

Documentation/devicetree/bindings/mtd/lpc32xx-slc.txt

···
+NXP LPC32xx SoC NAND SLC controller
+
+Required properties:
+- compatible: "nxp,lpc3220-slc"
+- reg: Address and size of the controller
+- nand-on-flash-bbt: Use bad block table on flash
+- gpios: GPIO specification for NAND write protect
+
+The following required properties are very controller specific. See the LPC32xx
+User Manual:
+- nxp,wdr-clks: Delay before Ready signal is tested on write (W_RDY)
+- nxp,rdr-clks: Delay before Ready signal is tested on read (R_RDY)
+(The following values are specified in Hz, to make them independent of actual
+clock speed:)
+- nxp,wwidth: Write pulse width (W_WIDTH)
+- nxp,whold: Write hold time (W_HOLD)
+- nxp,wsetup: Write setup time (W_SETUP)
+- nxp,rwidth: Read pulse width (R_WIDTH)
+- nxp,rhold: Read hold time (R_HOLD)
+- nxp,rsetup: Read setup time (R_SETUP)
+
+Optional subnodes:
+- Partitions, see Documentation/devicetree/bindings/mtd/partition.txt
+
+Example:
+
+	slc: flash@20020000 {
+		compatible = "nxp,lpc3220-slc";
+		reg = <0x20020000 0x1000>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		nxp,wdr-clks = <14>;
+		nxp,wwidth = <40000000>;
+		nxp,whold = <100000000>;
+		nxp,wsetup = <100000000>;
+		nxp,rdr-clks = <14>;
+		nxp,rwidth = <40000000>;
+		nxp,rhold = <66666666>;
+		nxp,rsetup = <100000000>;
+		nand-on-flash-bbt;
+		gpios = <&gpio 5 19 1>; /* GPO_P3 19, active low */
+
+		mtd0@00000000 {
+			label = "phy3250-boot";
+			reg = <0x00000000 0x00064000>;
+			read-only;
+		};
+
+		...
+
+	};

drivers/mtd/nand/Kconfig

···
 	  This enables the driver for the NAND flash device found on
 	  PXA3xx processors
 
+config MTD_NAND_SLC_LPC32XX
+	tristate "NXP LPC32xx SLC Controller"
+	depends on ARCH_LPC32XX
+	help
+	  Enables support for NXP's LPC32XX SLC (i.e. for Single Level Cell
+	  chips) NAND controller. This is the default for the PHYTEC 3250
+	  reference board which contains a NAND256R3A2CZA6 chip.
+
+	  Please check the actual NAND chip connected and its support
+	  by the SLC NAND controller.
+
 config MTD_NAND_CM_X270
 	tristate "Support for NAND Flash on CM-X270 modules"
 	depends on MACH_ARMCORE

drivers/mtd/nand/Makefile

···
 obj-$(CONFIG_MTD_NAND_FSL_ELBC)		+= fsl_elbc_nand.o
 obj-$(CONFIG_MTD_NAND_FSL_IFC)		+= fsl_ifc_nand.o
 obj-$(CONFIG_MTD_NAND_FSL_UPM)		+= fsl_upm.o
+obj-$(CONFIG_MTD_NAND_SLC_LPC32XX)      += lpc32xx_slc.o
 obj-$(CONFIG_MTD_NAND_SH_FLCTL)		+= sh_flctl.o
 obj-$(CONFIG_MTD_NAND_MXC)		+= mxc_nand.o
 obj-$(CONFIG_MTD_NAND_SOCRATES)		+= socrates_nand.o

drivers/mtd/nand/lpc32xx_slc.c

···
+/*
+ * NXP LPC32XX NAND SLC driver
+ *
+ * Authors:
+ *    Kevin Wells <[e-mail]>
+ *    Roland Stigge <[e-mail]>
+ *
+ * Copyright © 2011 NXP Semiconductors
+ * Copyright © 2012 Roland Stigge
+ *
+ * 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.
+ */
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/gpio.h>
+#include <linux/of.h>
+#include <linux/of_mtd.h>
+#include <linux/of_gpio.h>
+#include <linux/amba/pl08x.h>
+
+#define LPC32XX_MODNAME		"lpc32xx-nand"
+
+/**********************************************************************
+* SLC NAND controller register offsets
+**********************************************************************/
+
+#define SLC_DATA(x)		(x + 0x000)
+#define SLC_ADDR(x)		(x + 0x004)
+#define SLC_CMD(x)		(x + 0x008)
+#define SLC_STOP(x)		(x + 0x00C)
+#define SLC_CTRL(x)		(x + 0x010)
+#define SLC_CFG(x)		(x + 0x014)
+#define SLC_STAT(x)		(x + 0x018)
+#define SLC_INT_STAT(x)		(x + 0x01C)
+#define SLC_IEN(x)		(x + 0x020)
+#define SLC_ISR(x)		(x + 0x024)
+#define SLC_ICR(x)		(x + 0x028)
+#define SLC_TAC(x)		(x + 0x02C)
+#define SLC_TC(x)		(x + 0x030)
+#define SLC_ECC(x)		(x + 0x034)
+#define SLC_DMA_DATA(x)		(x + 0x038)
+
+/**********************************************************************
+* slc_ctrl register definitions
+**********************************************************************/
+#define SLCCTRL_SW_RESET	(1 << 2) /* Reset the NAND controller bit */
+#define SLCCTRL_ECC_CLEAR	(1 << 1) /* Reset ECC bit */
+#define SLCCTRL_DMA_START	(1 << 0) /* Start DMA channel bit */
+
+/**********************************************************************
+* slc_cfg register definitions
+**********************************************************************/
+#define SLCCFG_CE_LOW		(1 << 5) /* Force CE low bit */
+#define SLCCFG_DMA_ECC		(1 << 4) /* Enable DMA ECC bit */
+#define SLCCFG_ECC_EN		(1 << 3) /* ECC enable bit */
+#define SLCCFG_DMA_BURST	(1 << 2) /* DMA burst bit */
+#define SLCCFG_DMA_DIR		(1 << 1) /* DMA write(0)/read(1) bit */
+#define SLCCFG_WIDTH		(1 << 0) /* External device width, 0=8bit */
+
+/**********************************************************************
+* slc_stat register definitions
+**********************************************************************/
+#define SLCSTAT_DMA_FIFO	(1 << 2) /* DMA FIFO has data bit */
+#define SLCSTAT_SLC_FIFO	(1 << 1) /* SLC FIFO has data bit */
+#define SLCSTAT_NAND_READY	(1 << 0) /* NAND device is ready bit */
+
+/**********************************************************************
+* slc_int_stat, slc_ien, slc_isr, and slc_icr register definitions
+**********************************************************************/
+#define SLCSTAT_INT_TC		(1 << 1) /* Transfer count bit */
+#define SLCSTAT_INT_RDY_EN	(1 << 0) /* Ready interrupt bit */
+
+/**********************************************************************
+* slc_tac register definitions
+**********************************************************************/
+/* Clock setting for RDY write sample wait time in 2*n clocks */
+#define SLCTAC_WDR(n)		(((n) & 0xF) << 28)
+/* Write pulse width in clock cycles, 1 to 16 clocks */
+#define SLCTAC_WWIDTH(n)	(((n) & 0xF) << 24)
+/* Write hold time of control and data signals, 1 to 16 clocks */
+#define SLCTAC_WHOLD(n)		(((n) & 0xF) << 20)
+/* Write setup time of control and data signals, 1 to 16 clocks */
+#define SLCTAC_WSETUP(n)	(((n) & 0xF) << 16)
+/* Clock setting for RDY read sample wait time in 2*n clocks */
+#define SLCTAC_RDR(n)		(((n) & 0xF) << 12)
+/* Read pulse width in clock cycles, 1 to 16 clocks */
+#define SLCTAC_RWIDTH(n)	(((n) & 0xF) << 8)
+/* Read hold time of control and data signals, 1 to 16 clocks */
+#define SLCTAC_RHOLD(n)		(((n) & 0xF) << 4)
+/* Read setup time of control and data signals, 1 to 16 clocks */
+#define SLCTAC_RSETUP(n)	(((n) & 0xF) << 0)
+
+/**********************************************************************
+* slc_ecc register definitions
+**********************************************************************/
+/* ECC line party fetch macro */
+#define SLCECC_TO_LINEPAR(n)	(((n) >> 6) & 0x7FFF)
+#define SLCECC_TO_COLPAR(n)	((n) & 0x3F)
+
+/*
+ * DMA requires storage space for the DMA local buffer and the hardware ECC
+ * storage area. The DMA local buffer is only used if DMA mapping fails
+ * during runtime.
+ */
+#define LPC32XX_DMA_DATA_SIZE		4096
+#define LPC32XX_ECC_SAVE_SIZE		((4096 / 256) * 4)
+
+/* Number of bytes used for ECC stored in NAND per 256 bytes */
+#define LPC32XX_SLC_DEV_ECC_BYTES	3
+
+/*
+ * If the NAND base clock frequency can't be fetched, this frequency will be
+ * used instead as the base. This rate is used to setup the timing registers
+ * used for NAND accesses.
+ */
+#define LPC32XX_DEF_BUS_RATE		133250000
+
+/* Milliseconds for DMA FIFO timeout (unlikely anyway) */
+#define LPC32XX_DMA_TIMEOUT		100
+
+/*
+ * NAND ECC Layout for small page NAND devices
+ * Note: For large and huge page devices, the default layouts are used
+ */
+static struct nand_ecclayout lpc32xx_nand_oob_16 = {
+	.eccbytes = 6,
+	.eccpos = {10, 11, 12, 13, 14, 15},
+	.oobfree = {
+		{ .offset = 0, .length = 4 },
+		{ .offset = 6, .length = 4 },
+	},
+};
+
+static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
+static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
+
+/*
+ * Small page FLASH BBT descriptors, marker at offset 0, version at offset 6
+ * Note: Large page devices used the default layout
+ */
+static struct nand_bbt_descr bbt_smallpage_main_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs =	0,
+	.len = 4,
+	.veroffs = 6,
+	.maxblocks = 4,
+	.pattern = bbt_pattern
+};
+
+static struct nand_bbt_descr bbt_smallpage_mirror_descr = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs =	0,
+	.len = 4,
+	.veroffs = 6,
+	.maxblocks = 4,
+	.pattern = mirror_pattern
+};
+
+/*
+ * NAND platform configuration structure
+ */
+struct lpc32xx_nand_cfg_slc {
+	uint32_t wdr_clks;
+	uint32_t wwidth;
+	uint32_t whold;
+	uint32_t wsetup;
+	uint32_t rdr_clks;
+	uint32_t rwidth;
+	uint32_t rhold;
+	uint32_t rsetup;
+	bool use_bbt;
+	unsigned wp_gpio;
+	struct mtd_partition *parts;
+	unsigned num_parts;
+};
+
+struct lpc32xx_nand_host {
+	struct nand_chip	nand_chip;
+	struct clk		*clk;
+	struct mtd_info		mtd;
+	void __iomem		*io_base;
+	struct lpc32xx_nand_cfg_slc *ncfg;
+
+	struct completion	comp;
+	struct dma_chan		*dma_chan;
+	uint32_t		dma_buf_len;
+	struct dma_slave_config	dma_slave_config;
+	struct scatterlist	sgl;
+
+	/*
+	 * DMA and CPU addresses of ECC work area and data buffer
+	 */
+	uint32_t		*ecc_buf;
+	uint8_t			*data_buf;
+	dma_addr_t		io_base_dma;
+};
+
+static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
+{
+	uint32_t clkrate, tmp;
+
+	/* Reset SLC controller */
+	writel(SLCCTRL_SW_RESET, SLC_CTRL(host->io_base));
+	udelay(1000);
+
+	/* Basic setup */
+	writel(0, SLC_CFG(host->io_base));
+	writel(0, SLC_IEN(host->io_base));
+	writel((SLCSTAT_INT_TC | SLCSTAT_INT_RDY_EN),
+		SLC_ICR(host->io_base));
+
+	/* Get base clock for SLC block */
+	clkrate = clk_get_rate(host->clk);
+	if (clkrate == 0)
+		clkrate = LPC32XX_DEF_BUS_RATE;
+
+	/* Compute clock setup values */
+	tmp = SLCTAC_WDR(host->ncfg->wdr_clks) |
+		SLCTAC_WWIDTH(1 + (clkrate / host->ncfg->wwidth)) |
+		SLCTAC_WHOLD(1 + (clkrate / host->ncfg->whold)) |
+		SLCTAC_WSETUP(1 + (clkrate / host->ncfg->wsetup)) |
+		SLCTAC_RDR(host->ncfg->rdr_clks) |
+		SLCTAC_RWIDTH(1 + (clkrate / host->ncfg->rwidth)) |
+		SLCTAC_RHOLD(1 + (clkrate / host->ncfg->rhold)) |
+		SLCTAC_RSETUP(1 + (clkrate / host->ncfg->rsetup));
+	writel(tmp, SLC_TAC(host->io_base));
+}
+
+/*
+ * Hardware specific access to control lines
+ */
+static void lpc32xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
+	unsigned int ctrl)
+{
+	uint32_t tmp;
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+
+	/* Does CE state need to be changed? */
+	tmp = readl(SLC_CFG(host->io_base));
+	if (ctrl & NAND_NCE)
+		tmp |= SLCCFG_CE_LOW;
+	else
+		tmp &= ~SLCCFG_CE_LOW;
+	writel(tmp, SLC_CFG(host->io_base));
+
+	if (cmd != NAND_CMD_NONE) {
+		if (ctrl & NAND_CLE)
+			writel(cmd, SLC_CMD(host->io_base));
+		else
+			writel(cmd, SLC_ADDR(host->io_base));
+	}
+}
+
+/*
+ * Read the Device Ready pin
+ */
+static int lpc32xx_nand_device_ready(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+	int rdy = 0;
+
+	if ((readl(SLC_STAT(host->io_base)) & SLCSTAT_NAND_READY) != 0)
+		rdy = 1;
+
+	return rdy;
+}
+
+/*
+ * Enable NAND write protect
+ */
+static void lpc32xx_wp_enable(struct lpc32xx_nand_host *host)
+{
+	gpio_set_value(host->ncfg->wp_gpio, 0);
+}
+
+/*
+ * Disable NAND write protect
+ */
+static void lpc32xx_wp_disable(struct lpc32xx_nand_host *host)
+{
+	gpio_set_value(host->ncfg->wp_gpio, 1);
+}
+
+/*
+ * Prepares SLC for transfers with H/W ECC enabled
+ */
+static void lpc32xx_nand_ecc_enable(struct mtd_info *mtd, int mode)
+{
+	/* Hardware ECC is enabled automatically in hardware as needed */
+}
+
+/*
+ * Calculates the ECC for the data
+ */
+static int lpc32xx_nand_ecc_calculate(struct mtd_info *mtd,
+				      const unsigned char *buf,
+				      unsigned char *code)
+{
+	/*
+	 * ECC is calculated automatically in hardware during syndrome read
+	 * and write operations, so it doesn't need to be calculated here.
+	 */
+	return 0;
+}
+
+/*
+ * Read a single byte from NAND device
+ */
+static uint8_t lpc32xx_nand_read_byte(struct mtd_info *mtd)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+
+	return (uint8_t)readl(SLC_DATA(host->io_base));
+}
+
+/*
+ * Simple device read without ECC
+ */
+static void lpc32xx_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+
+	/* Direct device read with no ECC */
+	while (len-- > 0)
+		*buf++ = (uint8_t)readl(SLC_DATA(host->io_base));
+}
+
+/*
+ * Simple device write without ECC
+ */
+static void lpc32xx_nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+
+	/* Direct device write with no ECC */
+	while (len-- > 0)
+		writel((uint32_t)*buf++, SLC_DATA(host->io_base));
+}
+
+/*
+ * Verify data in buffer to data on device
+ */
+static int lpc32xx_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+	int i;
+
+	/* DATA register must be read as 32 bits or it will fail */
+	for (i = 0; i < len; i++) {
+		if (buf[i] != (uint8_t)readl(SLC_DATA(host->io_base)))
+			return -EFAULT;
+	}
+
+	return 0;
+}
+
+/*
+ * Read the OOB data from the device without ECC using FIFO method
+ */
+static int lpc32xx_nand_read_oob_syndrome(struct mtd_info *mtd,
+					  struct nand_chip *chip, int page)
+{
+	chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
+	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	return 0;
+}
+
+/*
+ * Write the OOB data to the device without ECC using FIFO method
+ */
+static int lpc32xx_nand_write_oob_syndrome(struct mtd_info *mtd,
+	struct nand_chip *chip, int page)
+{
+	int status;
+
+	chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
+	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	/* Send command to program the OOB data */
+	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+
+	status = chip->waitfunc(mtd, chip);
+
+	return status & NAND_STATUS_FAIL ? -EIO : 0;
+}
+
+/*
+ * Fills in the ECC fields in the OOB buffer with the hardware generated ECC
+ */
+static void lpc32xx_slc_ecc_copy(uint8_t *spare, const uint32_t *ecc, int count)
+{
+	int i;
+
+	for (i = 0; i < (count * 3); i += 3) {
+		uint32_t ce = ecc[i / 3];
+		ce = ~(ce << 2) & 0xFFFFFF;
+		spare[i + 2] = (uint8_t)(ce & 0xFF);
+		ce >>= 8;
+		spare[i + 1] = (uint8_t)(ce & 0xFF);
+		ce >>= 8;
+		spare[i] = (uint8_t)(ce & 0xFF);
+	}
+}
+
+static void lpc32xx_dma_complete_func(void *completion)
+{
+	complete(completion);
+}
+
+static int lpc32xx_xmit_dma(struct mtd_info *mtd, dma_addr_t dma,
+			    void *mem, int len, enum dma_transfer_direction dir)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+	struct dma_async_tx_descriptor *desc;
+	int flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
+	int res;
+
+	host->dma_slave_config.direction = dir;
+	host->dma_slave_config.src_addr = dma;
+	host->dma_slave_config.dst_addr = dma;
+	host->dma_slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	host->dma_slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	host->dma_slave_config.src_maxburst = 4;
+	host->dma_slave_config.dst_maxburst = 4;
+	/* DMA controller does flow control: */
+	host->dma_slave_config.device_fc = false;
+	if (dmaengine_slave_config(host->dma_chan, &host->dma_slave_config)) {
+		dev_err(mtd->dev.parent, "Failed to setup DMA slave\n");
+		return -ENXIO;
+	}
+
+	sg_init_one(&host->sgl, mem, len);
+
+	res = dma_map_sg(host->dma_chan->device->dev, &host->sgl, 1,
+			 DMA_BIDIRECTIONAL);
+	if (res != 1) {
+		dev_err(mtd->dev.parent, "Failed to map sg list\n");
+		return -ENXIO;
+	}
+	desc = dmaengine_prep_slave_sg(host->dma_chan, &host->sgl, 1, dir,
+				       flags);
+	if (!desc) {
+		dev_err(mtd->dev.parent, "Failed to prepare slave sg\n");
+		goto out1;
+	}
+
+	init_completion(&host->comp);
+	desc->callback = lpc32xx_dma_complete_func;
+	desc->callback_param = &host->comp;
+
+	dmaengine_submit(desc);
+	dma_async_issue_pending(host->dma_chan);
+
+	wait_for_completion_timeout(&host->comp, msecs_to_jiffies(1000));
+
+	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
+		     DMA_BIDIRECTIONAL);
+
+	return 0;
+out1:
+	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
+		     DMA_BIDIRECTIONAL);
+	return -ENXIO;
+}
+
+/*
+ * DMA read/write transfers with ECC support
+ */
+static int lpc32xx_xfer(struct mtd_info *mtd, uint8_t *buf, int eccsubpages,
+			int read)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct lpc32xx_nand_host *host = chip->priv;
+	int i, status = 0;
+	unsigned long timeout;
+	int res;
+	enum dma_transfer_direction dir =
+		read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
+	uint8_t *dma_buf;
+	bool dma_mapped;
+
+	if ((void *)buf <= high_memory) {
+		dma_buf = buf;
+		dma_mapped = true;
+	} else {
+		dma_buf = host->data_buf;
+		dma_mapped = false;
+		if (!read)
+			memcpy(host->data_buf, buf, mtd->writesize);
+	}
+
+	if (read) {
+		writel(readl(SLC_CFG(host->io_base)) |
+		       SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
+		       SLCCFG_DMA_BURST, SLC_CFG(host->io_base));
+	} else {
+		writel((readl(SLC_CFG(host->io_base)) |
+			SLCCFG_ECC_EN | SLCCFG_DMA_ECC | SLCCFG_DMA_BURST) &
+		       ~SLCCFG_DMA_DIR,
+			SLC_CFG(host->io_base));
+	}
+
+	/* Clear initial ECC */
+	writel(SLCCTRL_ECC_CLEAR, SLC_CTRL(host->io_base));
+
+	/* Transfer size is data area only */
+	writel(mtd->writesize, SLC_TC(host->io_base));
+
+	/* Start transfer in the NAND controller */
+	writel(readl(SLC_CTRL(host->io_base)) | SLCCTRL_DMA_START,
+	       SLC_CTRL(host->io_base));
+
+	for (i = 0; i < chip->ecc.steps; i++) {
+		/* Data */
+		res = lpc32xx_xmit_dma(mtd, SLC_DMA_DATA(host->io_base_dma),
+				       dma_buf + i * chip->ecc.size,
+				       mtd->writesize / chip->ecc.steps, dir);
+		if (res)
+			return res;
+
+		/* Always _read_ ECC */
+		if (i == chip->ecc.steps - 1)
+			break;
+		if (!read) /* ECC availability delayed on write */
+			udelay(10);
+		res = lpc32xx_xmit_dma(mtd, SLC_ECC(host->io_base_dma),
+				       &host->ecc_buf[i], 4, DMA_DEV_TO_MEM);
+		if (res)
+			return res;
+	}
+
+	/*
+	 * According to NXP, the DMA can be finished here, but the NAND
+	 * controller may still have buffered data. After porting to using the
+	 * dmaengine DMA driver (amba-pl080), the condition (DMA_FIFO empty)
+	 * appears to be always true, according to tests. Keeping the check for
+	 * safety reasons for now.
+	 */
+	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) {
+		dev_warn(mtd->dev.parent, "FIFO not empty!\n");
+		timeout = jiffies + msecs_to_jiffies(LPC32XX_DMA_TIMEOUT);
+		while ((readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) &&
+		       time_before(jiffies, timeout))
+			cpu_relax();
+		if (!time_before(jiffies, timeout)) {
+			dev_err(mtd->dev.parent, "FIFO held data too long\n");
+			status = -EIO;
+		}
+	}
+
+	/* Read last calculated ECC value */
+	if (!read)
+		udelay(10);
+	host->ecc_buf[chip->ecc.steps - 1] =
+		readl(SLC_ECC(host->io_base));
+
+	/* Flush DMA */
+	dmaengine_terminate_all(host->dma_chan);
+
+	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO ||
+	    readl(SLC_TC(host->io_base))) {
+		/* Something is left in the FIFO, something is wrong */
+		dev_err(mtd->dev.parent, "DMA FIFO failure\n");
+		status = -EIO;
+	}
+
+	/* Stop DMA & HW ECC */
+	writel(readl(SLC_CTRL(host->io_base)) & ~SLCCTRL_DMA_START,
+	       SLC_CTRL(host->io_base));
+	writel(readl(SLC_CFG(host->io_base)) &
+	       ~(SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
+		 SLCCFG_DMA_BURST), SLC_CFG(host->io_base));
+
+	if (!dma_mapped && read)
+		memcpy(buf, host->data_buf, mtd->writesize);
+
+	return status;
+}
+
+/*
+ * Read the data and OOB data from the device, use ECC correction with the
+ * data, disable ECC for the OOB data
+ */
+static int lpc32xx_nand_read_page_syndrome(struct mtd_info *mtd,
+					   struct nand_chip *chip, uint8_t *buf,
+					   int oob_required, int page)
+{
+	struct lpc32xx_nand_host *host = chip->priv;
+	int stat, i, status;
+	uint8_t *oobecc, tmpecc[LPC32XX_ECC_SAVE_SIZE];
+
+	/* Issue read command */
+	chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
+
+	/* Read data and oob, calculate ECC */
+	status = lpc32xx_xfer(mtd, buf, chip->ecc.steps, 1);
+
+	/* Get OOB data */
+	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	/* Convert to stored ECC format */
+	lpc32xx_slc_ecc_copy(tmpecc, (uint32_t *) host->ecc_buf, chip->ecc.steps);
+
+	/* Pointer to ECC data retrieved from NAND spare area */
+	oobecc = chip->oob_poi + chip->ecc.layout->eccpos[0];
+
+	for (i = 0; i < chip->ecc.steps; i++) {
+		stat = chip->ecc.correct(mtd, buf, oobecc,
+					 &tmpecc[i * chip->ecc.bytes]);
+		if (stat < 0)
+			mtd->ecc_stats.failed++;
+		else
+			mtd->ecc_stats.corrected += stat;
+
+		buf += chip->ecc.size;
+		oobecc += chip->ecc.bytes;
+	}
+
+	return status;
+}
+
+/*
+ * Read the data and OOB data from the device, no ECC correction with the
+ * data or OOB data
+ */
+static int lpc32xx_nand_read_page_raw_syndrome(struct mtd_info *mtd,
+					       struct nand_chip *chip,
+					       uint8_t *buf, int oob_required,
+					       int page)
+{
+	/* Issue read command */
+	chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
+
+	/* Raw reads can just use the FIFO interface */
+	chip->read_buf(mtd, buf, chip->ecc.size * chip->ecc.steps);
+	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	return 0;
+}
+
+/*
+ * Write the data and OOB data to the device, use ECC with the data,
+ * disable ECC for the OOB data
+ */
+static int lpc32xx_nand_write_page_syndrome(struct mtd_info *mtd,
+					    struct nand_chip *chip,
+					    const uint8_t *buf, int oob_required)
+{
+	struct lpc32xx_nand_host *host = chip->priv;
+	uint8_t *pb = chip->oob_poi + chip->ecc.layout->eccpos[0];
+	int error;
+
+	/* Write data, calculate ECC on outbound data */
+	error = lpc32xx_xfer(mtd, (uint8_t *)buf, chip->ecc.steps, 0);
+	if (error)
+		return error;
+
+	/*
+	 * The calculated ECC needs some manual work done to it before
+	 * committing it to NAND. Process the calculated ECC and place
+	 * the resultant values directly into the OOB buffer. */
+	lpc32xx_slc_ecc_copy(pb, (uint32_t *)host->ecc_buf, chip->ecc.steps);
+
+	/* Write ECC data to device */
+	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+	return 0;
+}
+
+/*
+ * Write the data and OOB data to the device, no ECC correction with the
+ * data or OOB data
+ */
+static int lpc32xx_nand_write_page_raw_syndrome(struct mtd_info *mtd,
+						struct nand_chip *chip,
+						const uint8_t *buf,
+						int oob_required)
+{
+	/* Raw writes can just use the FIFO interface */
+	chip->write_buf(mtd, buf, chip->ecc.size * chip->ecc.steps);
+	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+	return 0;
+}
+
+static bool lpc32xx_dma_filter(struct dma_chan *chan, void *param)
+{
+	struct pl08x_dma_chan *ch =
+		container_of(chan, struct pl08x_dma_chan, chan);
+
+	/* In LPC32xx's PL080 DMA wiring, the SLC NAND DMA signal is #1 */
+	if (ch->cd->min_signal == 1)
+		return true;
+	return false;
+}
+
+static int lpc32xx_nand_dma_setup(struct lpc32xx_nand_host *host)
+{
+	struct mtd_info *mtd = &host->mtd;
+	dma_cap_mask_t mask;
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+	host->dma_chan = dma_request_channel(mask, lpc32xx_dma_filter, NULL);
+	if (!host->dma_chan) {
+		dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static struct lpc32xx_nand_cfg_slc *lpc32xx_parse_dt(struct device *dev)
+{
+	struct lpc32xx_nand_cfg_slc *pdata;
+	struct device_node *np = dev->of_node;
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		dev_err(dev, "could not allocate memory for platform data\n");
+		return NULL;
+	}
+
+	of_property_read_u32(np, "nxp,wdr-clks", &pdata->wdr_clks);
+	of_property_read_u32(np, "nxp,wwidth", &pdata->wwidth);
+	of_property_read_u32(np, "nxp,whold", &pdata->whold);
+	of_property_read_u32(np, "nxp,wsetup", &pdata->wsetup);
+	of_property_read_u32(np, "nxp,rdr-clks", &pdata->rdr_clks);
+	of_property_read_u32(np, "nxp,rwidth", &pdata->rwidth);
+	of_property_read_u32(np, "nxp,rhold", &pdata->rhold);
+	of_property_read_u32(np, "nxp,rsetup", &pdata->rsetup);
+
+	if (!pdata->wdr_clks || !pdata->wwidth || !pdata->whold ||
+	    !pdata->wsetup || !pdata->rdr_clks || !pdata->rwidth ||
+	    !pdata->rhold || !pdata->rsetup) {
+		dev_err(dev, "chip parameters not specified correctly\n");
+		return NULL;
+	}
+
+	pdata->use_bbt = of_get_nand_on_flash_bbt(np);
+	pdata->wp_gpio = of_get_named_gpio_flags(np, "gpios", 0, NULL);
+
+	return pdata;
+}
+#else
+static struct lpc32xx_nand_cfg_slc *lpc32xx_parse_dt(struct device *dev)
+{
+	return NULL;
+}
+#endif
+
+/*
+ * Probe for NAND controller
+ */
+static int __devinit lpc32xx_nand_probe(struct platform_device *pdev)
+{
+	struct lpc32xx_nand_host *host;
+	struct mtd_info *mtd;
+	struct nand_chip *chip;
+	struct resource *rc;
+	struct mtd_part_parser_data ppdata = {};
+	int res;
+
+	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (rc == NULL) {
+		dev_err(&pdev->dev, "No memory resource found for device\n");
+		return -EBUSY;
+	}
+
+	/* Allocate memory for the device structure (and zero it) */
+	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
+	if (!host) {
+		dev_err(&pdev->dev, "failed to allocate device structure\n");
+		return -ENOMEM;
+	}
+	host->io_base_dma = rc->start;
+
+	host->io_base = devm_request_and_ioremap(&pdev->dev, rc);
+	if (host->io_base == NULL) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		return -ENOMEM;
+	}
+
+	if (pdev->dev.of_node)
+		host->ncfg = lpc32xx_parse_dt(&pdev->dev);
+	else
+		host->ncfg = pdev->dev.platform_data;
+	if (!host->ncfg) {
+		dev_err(&pdev->dev, "Missing platform data\n");
+		return -ENOENT;
+	}
+	if (gpio_request(host->ncfg->wp_gpio, "NAND WP")) {
+		dev_err(&pdev->dev, "GPIO not available\n");
+		return -EBUSY;
+	}
+	lpc32xx_wp_disable(host);
+
+	mtd = &host->mtd;
+	chip = &host->nand_chip;
+	chip->priv = host;
+	mtd->priv = chip;
+	mtd->owner = THIS_MODULE;
+	mtd->dev.parent = &pdev->dev;
+
+	/* Get NAND clock */
+	host->clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(host->clk)) {
+		dev_err(&pdev->dev, "Clock failure\n");
+		res = -ENOENT;
+		goto err_exit1;
+	}
+	clk_enable(host->clk);
+
+	/* Set NAND IO addresses and command/ready functions */
+	chip->IO_ADDR_R = SLC_DATA(host->io_base);
+	chip->IO_ADDR_W = SLC_DATA(host->io_base);
+	chip->cmd_ctrl = lpc32xx_nand_cmd_ctrl;
+	chip->dev_ready = lpc32xx_nand_device_ready;
+	chip->chip_delay = 20; /* 20us command delay time */
+
+	/* Init NAND controller */
+	lpc32xx_nand_setup(host);
+
+	platform_set_drvdata(pdev, host);
+
+	/* NAND callbacks for LPC32xx SLC hardware */
+	chip->ecc.mode = NAND_ECC_HW_SYNDROME;
+	chip->read_byte = lpc32xx_nand_read_byte;
+	chip->read_buf = lpc32xx_nand_read_buf;
+	chip->write_buf = lpc32xx_nand_write_buf;
+	chip->ecc.read_page_raw = lpc32xx_nand_read_page_raw_syndrome;
+	chip->ecc.read_page = lpc32xx_nand_read_page_syndrome;
+	chip->ecc.write_page_raw = lpc32xx_nand_write_page_raw_syndrome;
+	chip->ecc.write_page = lpc32xx_nand_write_page_syndrome;
+	chip->ecc.write_oob = lpc32xx_nand_write_oob_syndrome;
+	chip->ecc.read_oob = lpc32xx_nand_read_oob_syndrome;
+	chip->ecc.calculate = lpc32xx_nand_ecc_calculate;
+	chip->ecc.correct = nand_correct_data;
+	chip->ecc.strength = 1;
+	chip->ecc.hwctl = lpc32xx_nand_ecc_enable;
+	chip->verify_buf = lpc32xx_verify_buf;
+
+	/* bitflip_threshold's default is defined as ecc_strength anyway.
+	 * Unfortunately, it is set only later at add_mtd_device(). Meanwhile
+	 * being 0, it causes bad block table scanning errors in
+	 * nand_scan_tail(), so preparing it here already. */
+	mtd->bitflip_threshold = chip->ecc.strength;
+
+	/*
+	 * Allocate a large enough buffer for a single huge page plus
+	 * extra space for the spare area and ECC storage area
+	 */
+	host->dma_buf_len = LPC32XX_DMA_DATA_SIZE + LPC32XX_ECC_SAVE_SIZE;
+	host->data_buf = devm_kzalloc(&pdev->dev, host->dma_buf_len,
+				      GFP_KERNEL);
+	if (host->data_buf == NULL) {
+		dev_err(&pdev->dev, "Error allocating memory\n");
+		res = -ENOMEM;
+		goto err_exit2;
+	}
+
+	res = lpc32xx_nand_dma_setup(host);
+	if (res) {
+		res = -EIO;
+		goto err_exit2;
+	}
+
+	/* Find NAND device */
+	if (nand_scan_ident(mtd, 1, NULL)) {
+		res = -ENXIO;
+		goto err_exit3;
+	}
+
+	/* OOB and ECC CPU and DMA work areas */
+	host->ecc_buf = (uint32_t *)(host->data_buf + LPC32XX_DMA_DATA_SIZE);
+
+	/*
+	 * Small page FLASH has a unique OOB layout, but large and huge
+	 * page FLASH use the standard layout. Small page FLASH uses a
+	 * custom BBT marker layout.
+	 */
+	if (mtd->writesize <= 512)
+		chip->ecc.layout = &lpc32xx_nand_oob_16;
+
+	/* These sizes remain the same regardless of page size */
+	chip->ecc.size = 256;
+	chip->ecc.bytes = LPC32XX_SLC_DEV_ECC_BYTES;
+	chip->ecc.prepad = chip->ecc.postpad = 0;
+
+	/* Avoid extra scan if using BBT, setup BBT support */
+	if (host->ncfg->use_bbt) {
+		chip->options |= NAND_SKIP_BBTSCAN;
+		chip->bbt_options |= NAND_BBT_USE_FLASH;
+
+		/*
+		 * Use a custom BBT marker setup for small page FLASH that
+		 * won't interfere with the ECC layout. Large and huge page
+		 * FLASH use the standard layout.
+		 */
+		if (mtd->writesize <= 512) {
+			chip->bbt_td = &bbt_smallpage_main_descr;
+			chip->bbt_md = &bbt_smallpage_mirror_descr;
+		}
+	}
+
+	/*
+	 * Fills out all the uninitialized function pointers with the defaults
+	 */
+	if (nand_scan_tail(mtd)) {
+		res = -ENXIO;
+		goto err_exit3;
+	}
+
+	/* Standard layout in FLASH for bad block tables */
+	if (host->ncfg->use_bbt) {
+		if (nand_default_bbt(mtd) < 0)
+			dev_err(&pdev->dev,
+			       "Error initializing default bad block tables\n");
+	}
+
+	mtd->name = "nxp_lpc3220_slc";
+	ppdata.of_node = pdev->dev.of_node;
+	res = mtd_device_parse_register(mtd, NULL, &ppdata, host->ncfg->parts,
+					host->ncfg->num_parts);
+	if (!res)
+		return res;
+
+	nand_release(mtd);
+
+err_exit3:
+	dma_release_channel(host->dma_chan);
+err_exit2:
+	clk_disable(host->clk);
+	clk_put(host->clk);
+	platform_set_drvdata(pdev, NULL);
+err_exit1:
+	lpc32xx_wp_enable(host);
+	gpio_free(host->ncfg->wp_gpio);
+
+	return res;
+}
+
+/*
+ * Remove NAND device.
+ */
+static int __devexit lpc32xx_nand_remove(struct platform_device *pdev)
+{
+	uint32_t tmp;
+	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
+	struct mtd_info *mtd = &host->mtd;
+
+	nand_release(mtd);
+	dma_release_channel(host->dma_chan);
+
+	/* Force CE high */
+	tmp = readl(SLC_CTRL(host->io_base));
+	tmp &= ~SLCCFG_CE_LOW;
+	writel(tmp, SLC_CTRL(host->io_base));
+
+	clk_disable(host->clk);
+	clk_put(host->clk);
+	platform_set_drvdata(pdev, NULL);
+	lpc32xx_wp_enable(host);
+	gpio_free(host->ncfg->wp_gpio);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int lpc32xx_nand_resume(struct platform_device *pdev)
+{
+	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
+
+	/* Re-enable NAND clock */
+	clk_enable(host->clk);
+
+	/* Fresh init of NAND controller */
+	lpc32xx_nand_setup(host);
+
+	/* Disable write protect */
+	lpc32xx_wp_disable(host);
+
+	return 0;
+}
+
+static int lpc32xx_nand_suspend(struct platform_device *pdev, pm_message_t pm)
+{
+	uint32_t tmp;
+	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
+
+	/* Force CE high */
+	tmp = readl(SLC_CTRL(host->io_base));
+	tmp &= ~SLCCFG_CE_LOW;
+	writel(tmp, SLC_CTRL(host->io_base));
+
+	/* Enable write protect for safety */
+	lpc32xx_wp_enable(host);
+
+	/* Disable clock */
+	clk_disable(host->clk);
+
+	return 0;
+}
+
+#else
+#define lpc32xx_nand_resume NULL
+#define lpc32xx_nand_suspend NULL
+#endif
+
+#if defined(CONFIG_OF)
+static const struct of_device_id lpc32xx_nand_match[] = {
+	{ .compatible = "nxp,lpc3220-slc" },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, lpc32xx_nand_match);
+#endif
+
+static struct platform_driver lpc32xx_nand_driver = {
+	.probe		= lpc32xx_nand_probe,
+	.remove		= __devexit_p(lpc32xx_nand_remove),
+	.resume		= lpc32xx_nand_resume,
+	.suspend	= lpc32xx_nand_suspend,
+	.driver		= {
+		.name	= LPC32XX_MODNAME,
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(lpc32xx_nand_match),
+	},
+};
+
+module_platform_driver(lpc32xx_nand_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Kevin Wells <[e-mail]>");
+MODULE_AUTHOR("Roland Stigge <[e-mail]>");
+MODULE_DESCRIPTION("NAND driver for the NXP LPC32XX SLC controller");