diff mbox

[1/2] mtd: spi-nor: add driver for NXP SPI Flash Interface (SPIFI)

Message ID 1432921816-10765-2-git-send-email-manabian@gmail.com
State Superseded
Headers show

Commit Message

Joachim Eastwood May 29, 2015, 5:50 p.m. UTC
Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
controller that is found newer NXP MCU devices.

The controller supports serial SPI Flash devices with 1-, 2-
and 4-bit width in either SPI mode 0 or 3. The controller
can operate in either command or memory mode. In memory mode
the Flash is exposed as normal memory and can be directly
accessed by the CPU.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
---
 drivers/mtd/spi-nor/Kconfig     |  10 +
 drivers/mtd/spi-nor/Makefile    |   1 +
 drivers/mtd/spi-nor/nxp-spifi.c | 508 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 519 insertions(+)
 create mode 100644 drivers/mtd/spi-nor/nxp-spifi.c

Comments

Ezequiel Garcia May 30, 2015, 3:43 p.m. UTC | #1
Hi Joachim,

Looks pretty neat. I've just a couple comments.

On 05/29/2015 02:50 PM, Joachim Eastwood wrote:
> Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
> controller that is found newer NXP MCU devices.
> 
> The controller supports serial SPI Flash devices with 1-, 2-
> and 4-bit width in either SPI mode 0 or 3. The controller
> can operate in either command or memory mode. In memory mode
> the Flash is exposed as normal memory and can be directly
> accessed by the CPU.
> 
> Signed-off-by: Joachim Eastwood <manabian@gmail.com>
> ---
>  drivers/mtd/spi-nor/Kconfig     |  10 +
>  drivers/mtd/spi-nor/Makefile    |   1 +
>  drivers/mtd/spi-nor/nxp-spifi.c | 508 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 519 insertions(+)
>  create mode 100644 drivers/mtd/spi-nor/nxp-spifi.c
> 
> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
> index 64a4f0edabc7..f10a37f1a4ef 100644
> --- a/drivers/mtd/spi-nor/Kconfig
> +++ b/drivers/mtd/spi-nor/Kconfig
> @@ -28,4 +28,14 @@ config SPI_FSL_QUADSPI
>  	  This enables support for the Quad SPI controller in master mode.
>  	  We only connect the NOR to this controller now.
>  
> +config SPI_NXP_SPIFI
> +	tristate "NXP SPI Flash Interface (SPIFI)"
> +	depends on OF && (ARCH_LPC18XX || COMPILE_TEST)

Since you are adding COMPILE_TEST, maybe you want
'depends on HAS_IOMEM' as well?

> +	help
> +	  Enable support for the NXP LPC SPI Flash Interface controller.
> +
> +	  SPIFI is a specialized controller for connecting serial SPI
> +	  Flash. Enable this option if you have a device with a SPIFI
> +	  controller and want to access the Flash as a mtd device.
> +
>  endif # MTD_SPI_NOR
> diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
> index 6a7ce1462247..e53333ef8582 100644
> --- a/drivers/mtd/spi-nor/Makefile
> +++ b/drivers/mtd/spi-nor/Makefile
> @@ -1,2 +1,3 @@
>  obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
>  obj-$(CONFIG_SPI_FSL_QUADSPI)	+= fsl-quadspi.o
> +obj-$(CONFIG_SPI_NXP_SPIFI)	+= nxp-spifi.o
> diff --git a/drivers/mtd/spi-nor/nxp-spifi.c b/drivers/mtd/spi-nor/nxp-spifi.c
> new file mode 100644
> index 000000000000..cbfe0bb16f81
> --- /dev/null
> +++ b/drivers/mtd/spi-nor/nxp-spifi.c
> @@ -0,0 +1,508 @@
> +/*
> + * SPI-NOR driver for NXP SPI Flash Interface (SPIFI)
> + *
> + * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
> + *
> + * Based on Freescale QuadSPI driver:
> + * Copyright (C) 2013 Freescale Semiconductor, Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/mtd/partitions.h>
> +#include <linux/mtd/spi-nor.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/spi/spi.h>
> +
> +/* NXP SPIFI registers, bits and macros */
> +#define SPIFI_CTRL				0x000
> +#define  SPIFI_CTRL_TIMEOUT(timeout)		(timeout)
> +#define  SPIFI_CTRL_CSHIGH(cshigh)		((cshigh) << 16)
> +#define  SPIFI_CTRL_MODE3			BIT(23)
> +#define  SPIFI_CTRL_DUAL			BIT(28)
> +#define  SPIFI_CTRL_FBCLK			BIT(30)
> +#define SPIFI_CMD				0x004
> +#define  SPIFI_CMD_DATALEN(dlen)		(dlen & 0x3fff)
> +#define  SPIFI_CMD_DOUT				BIT(15)
> +#define  SPIFI_CMD_INTLEN(ilen)			((ilen) << 16)
> +#define  SPIFI_CMD_FIELDFORM(field)		((field) << 19)
> +#define  SPIFI_CMD_FIELDFORM_ALL_SERIAL		SPIFI_CMD_FIELDFORM(0x0)
> +#define  SPIFI_CMD_FIELDFORM_QUAD_DUAL_DATA	SPIFI_CMD_FIELDFORM(0x1)
> +#define  SPIFI_CMD_FRAMEFORM(frame)		((frame) << 21)
> +#define  SPIFI_CMD_FRAMEFORM_OPCODE_ONLY	SPIFI_CMD_FRAMEFORM(0x1)
> +#define  SPIFI_CMD_OPCODE(op)			((op) << 24)
> +#define SPIFI_ADDR				0x008
> +#define SPIFI_IDATA				0x00c
> +#define SPIFI_CLIMIT				0x010
> +#define SPIFI_DATA				0x014
> +#define SPIFI_MCMD				0x018
> +#define SPIFI_STAT				0x01c
> +#define  SPIFI_STAT_MCINIT			BIT(0)
> +#define  SPIFI_STAT_CMD				BIT(1)
> +#define  SPIFI_STAT_RESET			BIT(4)
> +
> +#define SPI_NOR_MAX_ID_LEN	6
> +
> +struct nxp_spifi {
> +	struct device *dev;
> +	struct clk *clk_spifi;
> +	struct clk *clk_reg;
> +	void __iomem *io_base;
> +	void __iomem *flash_base;
> +	struct mtd_info mtd;
> +	struct spi_nor nor;
> +	u32 mcmd;
> +};
> +
> +static int nxp_spifi_wait_for_event(struct nxp_spifi *spifi, u32 event)
> +{
> +	int retry = 3;
> +	u32 stat;
> +
> +	do {
> +		stat = readb(spifi->io_base + SPIFI_STAT);
> +		if (!(stat & event))
> +			return 0;
> +
> +		udelay(10);
> +	} while (retry--);
> +
> +	return -ETIMEDOUT;

This could be replaced with the readb_poll_timeout_atomic().
But it seems you would also use readb_poll_timeout(), since won't be
called in atomic context.

> +}
> +
> +static int nxp_spifi_wait_for_cmd(struct nxp_spifi *spifi)
> +{
> +	int ret;
> +
> +	ret = nxp_spifi_wait_for_event(spifi, SPIFI_STAT_CMD);
> +	if (ret)
> +		dev_warn(spifi->dev, "command timed out\n");
> +
> +	return ret;
> +}
> +
> +static int nxp_spifi_reset(struct nxp_spifi *spifi)
> +{
> +	int ret;
> +
> +	writel(SPIFI_STAT_RESET, spifi->io_base + SPIFI_STAT);
> +	ret = nxp_spifi_wait_for_event(spifi, SPIFI_STAT_RESET);
> +	if (ret)
> +		dev_warn(spifi->dev, "state reset timed out\n");
> +
> +	return ret;
> +}
> +
> +static int nxp_spifi_set_memory_mode_off(struct nxp_spifi *spifi)
> +{
> +	u32 stat;
> +	int ret;
> +
> +	stat = readb(spifi->io_base + SPIFI_STAT);
> +	if (!(stat & SPIFI_STAT_MCINIT))
> +		return 0;
> +
> +	ret = nxp_spifi_reset(spifi);
> +	if (ret)
> +		dev_err(spifi->dev, "unable to enter command mode\n");
> +
> +	return ret;
> +}
> +
> +static int nxp_spifi_set_memory_mode_on(struct nxp_spifi *spifi)
> +{
> +	int retry = 3;
> +	u32 stat;
> +
> +	stat = readb(spifi->io_base + SPIFI_STAT);
> +	if (stat & SPIFI_STAT_MCINIT)
> +		return 0;

Do you think it makes sense to cache the memory/command mode
instead of reading it? Would it affect throughput in any sense?

I'm thinking these slow-clocked microcontrollers might benefit from
such tricks, but I don't have actual numbers to back this up.

> +
> +	writel(spifi->mcmd, spifi->io_base + SPIFI_MCMD);
> +
> +	do {
> +		stat = readb(spifi->io_base + SPIFI_STAT);
> +		if (stat & SPIFI_STAT_MCINIT)
> +			return 0;
> +
> +		udelay(10);
> +	} while (retry--);

Same here about using iopoll variants.

> +
> +	dev_err(spifi->dev, "unable to enter memory mode\n");
> +
> +	return -ETIMEDOUT;
> +}
> +
> +static int nxp_spifi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
> +{
> +	struct nxp_spifi *spifi = nor->priv;
> +	u32 cmd;
> +	int ret;
> +
> +	ret = nxp_spifi_set_memory_mode_off(spifi);
> +	if (ret)
> +		return ret;
> +
> +	cmd = SPIFI_CMD_DATALEN(len) |
> +	      SPIFI_CMD_OPCODE(opcode) |
> +	      SPIFI_CMD_FIELDFORM_ALL_SERIAL |
> +	      SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
> +	writel(cmd, spifi->io_base + SPIFI_CMD);
> +
> +	while (len--)
> +		*buf++  = readb(spifi->io_base + SPIFI_DATA);

Nit: extra whitespace here.

> +
> +	return nxp_spifi_wait_for_cmd(spifi);
> +}
> +
> +static int nxp_spifi_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
> +			       int len, int write_enable)
> +{
> +	struct nxp_spifi *spifi = nor->priv;
> +	u32 cmd;
> +	int ret;
> +
> +	ret = nxp_spifi_set_memory_mode_off(spifi);
> +	if (ret)
> +		return ret;
> +
> +	cmd = SPIFI_CMD_DOUT |
> +	      SPIFI_CMD_DATALEN(len) |
> +	      SPIFI_CMD_OPCODE(opcode) |
> +	      SPIFI_CMD_FIELDFORM_ALL_SERIAL |
> +	      SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
> +	writel(cmd, spifi->io_base + SPIFI_CMD);
> +
> +	while (len--)
> +		writeb(*buf++, spifi->io_base + SPIFI_DATA);
> +
> +	return nxp_spifi_wait_for_cmd(spifi);
> +}
> +
> +static int nxp_spifi_read(struct spi_nor *nor, loff_t from, size_t len,
> +			  size_t *retlen, u_char *buf)
> +{
> +	struct nxp_spifi *spifi = nor->priv;
> +	int ret;
> +
> +	ret = nxp_spifi_set_memory_mode_on(spifi);
> +	if (ret)
> +		return ret;
> +
> +	memcpy_fromio(buf, spifi->flash_base + from, len);
> +	*retlen += len;
> +
> +	return 0;
> +}
> +
> +static void nxp_spifi_write(struct spi_nor *nor, loff_t to, size_t len,
> +			    size_t *retlen, const u_char *buf)
> +{
> +	struct nxp_spifi *spifi = nor->priv;
> +	u32 cmd;
> +	int ret;
> +
> +	ret = nxp_spifi_set_memory_mode_off(spifi);
> +	if (ret) {
> +		*retlen = 0;
> +		return;
> +	}
> +
> +	writel(to, spifi->io_base + SPIFI_ADDR);
> +	*retlen = len;
> +
> +	cmd = SPIFI_CMD_DOUT |
> +	      SPIFI_CMD_DATALEN(len) |
> +	      SPIFI_CMD_FIELDFORM_ALL_SERIAL |
> +	      SPIFI_CMD_OPCODE(nor->program_opcode) |
> +	      SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
> +	writel(cmd, spifi->io_base + SPIFI_CMD);
> +
> +	while (len--)
> +		writeb(*buf++, spifi->io_base + SPIFI_DATA);
> +
> +	nxp_spifi_wait_for_cmd(spifi);
> +}
> +
> +static int nxp_spifi_erase(struct spi_nor *nor, loff_t offs)
> +{
> +	struct nxp_spifi *spifi = nor->priv;
> +	u32 cmd;
> +	int ret;
> +
> +	ret = nxp_spifi_set_memory_mode_off(spifi);
> +	if (ret)
> +		return ret;
> +
> +	writel(offs, spifi->io_base + SPIFI_ADDR);
> +
> +	cmd = SPIFI_CMD_FIELDFORM_ALL_SERIAL |
> +	      SPIFI_CMD_OPCODE(nor->erase_opcode) |
> +	      SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
> +	writel(cmd, spifi->io_base + SPIFI_CMD);
> +
> +	return nxp_spifi_wait_for_cmd(spifi);
> +}
> +
> +static int nxp_spifi_setup_memory_cmd(struct nxp_spifi *spifi)
> +{
> +	switch (spifi->nor.flash_read) {
> +	case SPI_NOR_NORMAL:
> +	case SPI_NOR_FAST:
> +		spifi->mcmd = SPIFI_CMD_FIELDFORM_ALL_SERIAL;
> +		break;
> +	case SPI_NOR_DUAL:
> +	case SPI_NOR_QUAD:
> +		spifi->mcmd = SPIFI_CMD_FIELDFORM_QUAD_DUAL_DATA;
> +		break;
> +	default:
> +		dev_err(spifi->dev, "unsupported spi read mode\n");
> +		return -EINVAL;
> +	}
> +
> +	/* Memory mode supports address length between 1 and 4 */
> +	if (spifi->nor.addr_width < 1 || spifi->nor.addr_width > 4)
> +		return -EINVAL;
> +
> +	spifi->mcmd |= SPIFI_CMD_OPCODE(spifi->nor.read_opcode) |
> +		       SPIFI_CMD_INTLEN(spifi->nor.read_dummy / 8) |
> +		       SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
> +
> +	return 0;
> +}
> +
> +static void nxp_spifi_dummy_id_read(struct spi_nor *nor)
> +{
> +	u8 id[SPI_NOR_MAX_ID_LEN];
> +	nor->read_reg(nor, SPINOR_OP_RDID, id, SPI_NOR_MAX_ID_LEN);
> +}
> +
> +static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
> +				 struct device_node *np)
> +{
> +	struct mtd_part_parser_data ppdata;
> +	enum read_mode flash_read;
> +	u32 ctrl, property;
> +	char modalias[40];
> +	u16 mode = 0;
> +	int ret;
> +
> +	if (!of_property_read_u32(np, "spi-rx-bus-width", &property)) {
> +		switch (property) {
> +		case 1:
> +			break;
> +		case 2:
> +			mode |= SPI_RX_DUAL;
> +			break;
> +		case 4:
> +			mode |= SPI_RX_QUAD;
> +			break;
> +		default:
> +			dev_err(spifi->dev, "unsupported rx-bus-width\n");
> +			return -EINVAL;
> +		}
> +	}
> +
> +	if (of_find_property(np, "spi-cpha", NULL))
> +		mode |= SPI_CPHA;
> +
> +	if (of_find_property(np, "spi-cpol", NULL))
> +		mode |= SPI_CPOL;
> +
> +	/* Setup control register defaults */
> +	ctrl = SPIFI_CTRL_TIMEOUT(1000) |
> +	       SPIFI_CTRL_CSHIGH(15) |
> +	       SPIFI_CTRL_FBCLK;
> +
> +	if (mode & SPI_RX_DUAL) {
> +		ctrl |= SPIFI_CTRL_DUAL;
> +		flash_read = SPI_NOR_DUAL;
> +	} else if (mode & SPI_RX_QUAD) {
> +		ctrl &= ~SPIFI_CTRL_DUAL;
> +		flash_read = SPI_NOR_QUAD;
> +	} else {
> +		ctrl |= SPIFI_CTRL_DUAL;
> +		flash_read = SPI_NOR_NORMAL;
> +	}
> +
> +	switch (mode & (SPI_CPHA | SPI_CPOL)) {
> +	case SPI_MODE_0:
> +		ctrl &= ~SPIFI_CTRL_MODE3;
> +		break;
> +	case SPI_MODE_3:
> +		ctrl |= SPIFI_CTRL_MODE3;
> +		break;
> +	default:
> +		dev_err(spifi->dev, "only mode 0 and 3 supported\n");
> +		return -EINVAL;
> +	}
> +
> +	writel(ctrl, spifi->io_base + SPIFI_CTRL);
> +	dev_info(spifi->dev, "spifi ctrl = 0x%08x\n", ctrl);
> +
> +	spifi->mtd.priv  = &spifi->nor;
> +	spifi->nor.mtd   = &spifi->mtd;
> +	spifi->nor.dev   = spifi->dev;
> +	spifi->nor.priv  = spifi;
> +	spifi->nor.read  = nxp_spifi_read;
> +	spifi->nor.write = nxp_spifi_write;
> +	spifi->nor.erase = nxp_spifi_erase;
> +	spifi->nor.read_reg  = nxp_spifi_read_reg;
> +	spifi->nor.write_reg = nxp_spifi_write_reg;
> +
> +	ret = of_modalias_node(np, modalias, sizeof(modalias));
> +	if (ret < 0) {
> +		dev_err(spifi->dev, "unable to get device modalias\n");
> +		return ret;
> +	}
> +
> +	/*
> +	 * The first read on a hard reset isn't reliable so do a
> +	 * dummy read of the id before calling spi_nor_scan().
> +	 * The reason for this problem is unknown.
> +	 *
> +	 * The official NXP spifilib uses more or less the same
> +	 * workaround that is applied here by reading the device
> +	 * id multiple times.
> +	 */
> +	nxp_spifi_dummy_id_read(&spifi->nor);
> +
> +	ret = spi_nor_scan(&spifi->nor, modalias, flash_read);
> +	if (ret) {
> +		dev_err(spifi->dev, "device scan failed\n");
> +		return ret;
> +	}
> +
> +	ret = nxp_spifi_setup_memory_cmd(spifi);
> +	if (ret) {
> +		dev_err(spifi->dev, "memory command setup failed\n");
> +		return ret;
> +	}
> +
> +	ppdata.of_node = np;
> +	ret = mtd_device_parse_register(&spifi->mtd, NULL, &ppdata, NULL, 0);
> +	if (ret) {
> +		dev_err(spifi->dev, "mtd device parse failed\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int nxp_spifi_probe(struct platform_device *pdev)
> +{
> +	struct device_node *flash_np;
> +	struct nxp_spifi *spifi;
> +	struct resource *res;
> +	int ret;
> +
> +	spifi = devm_kzalloc(&pdev->dev, sizeof(*spifi), GFP_KERNEL);
> +	if (!spifi)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "spifi");
> +	spifi->io_base = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(spifi->io_base))
> +		return PTR_ERR(spifi->io_base);
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "flash");
> +	spifi->flash_base = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(spifi->flash_base))
> +		return PTR_ERR(spifi->flash_base);
> +

Just curious: is the memory mapping fixed?

> +	spifi->clk_spifi = devm_clk_get(&pdev->dev, "spifi");
> +	if (IS_ERR(spifi->clk_spifi)) {
> +		dev_err(&pdev->dev, "spifi clock not found\n");
> +		return PTR_ERR(spifi->clk_spifi);
> +	}
> +
> +	spifi->clk_reg = devm_clk_get(&pdev->dev, "reg");
> +	if (IS_ERR(spifi->clk_reg)) {
> +		dev_err(&pdev->dev, "reg clock not found\n");
> +		return PTR_ERR(spifi->clk_reg);
> +	}
> +
> +	ret = clk_prepare_enable(spifi->clk_reg);
> +	if (ret) {
> +		dev_err(&pdev->dev, "unable to enable reg clock\n");
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(spifi->clk_spifi);
> +	if (ret) {
> +		dev_err(&pdev->dev, "unable to enable spifi clock\n");
> +		goto dis_clk_reg;
> +	}
> +
> +	spifi->dev = &pdev->dev;
> +	platform_set_drvdata(pdev, spifi);
> +
> +	/* Initialize and reset device */
> +	nxp_spifi_reset(spifi);
> +	writel(0, spifi->io_base + SPIFI_IDATA);
> +	writel(0, spifi->io_base + SPIFI_MCMD);
> +	nxp_spifi_reset(spifi);
> +
> +	flash_np = of_get_next_available_child(pdev->dev.of_node, NULL);
> +	if (!flash_np) {
> +		dev_err(&pdev->dev, "no spi flash device to configure\n");
> +		ret = -ENODEV;
> +		goto dis_clks;
> +	}
> +
> +	ret = nxp_spifi_setup_flash(spifi, flash_np);
> +	if (ret) {
> +		dev_err(&pdev->dev, "unable to setup flash chip\n");
> +		goto dis_clks;
> +	}
> +
> +	return 0;
> +
> +dis_clks:
> +	clk_disable_unprepare(spifi->clk_spifi);
> +dis_clk_reg:
> +	clk_disable_unprepare(spifi->clk_reg);
> +	return ret;
> +}
> +
> +static int nxp_spifi_remove(struct platform_device *pdev)
> +{
> +	struct nxp_spifi *spifi = platform_get_drvdata(pdev);
> +
> +	mtd_device_unregister(&spifi->mtd);
> +	clk_disable_unprepare(spifi->clk_spifi);
> +	clk_disable_unprepare(spifi->clk_reg);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id nxp_spifi_match[] = {
> +	{.compatible = "nxp,lpc1773-spifi"},
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, nxp_spifi_match);
> +
> +static struct platform_driver nxp_spifi_driver = {
> +	.probe	= nxp_spifi_probe,
> +	.remove	= nxp_spifi_remove,
> +	.driver	= {
> +		.name = "nxp-spifi",
> +		.of_match_table = nxp_spifi_match,
> +	},
> +};
> +module_platform_driver(nxp_spifi_driver);
> +
> +MODULE_DESCRIPTION("NXP SPI Flash Interface driver");
> +MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>");
> +MODULE_LICENSE("GPL v2");
>
Joachim Eastwood May 30, 2015, 4:51 p.m. UTC | #2
Hi Ezequiel,

On 30 May 2015 at 17:43, Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> wrote:
> Hi Joachim,
>
> Looks pretty neat. I've just a couple comments.
>
> On 05/29/2015 02:50 PM, Joachim Eastwood wrote:
>> Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
>> controller that is found newer NXP MCU devices.
>>
>> The controller supports serial SPI Flash devices with 1-, 2-
>> and 4-bit width in either SPI mode 0 or 3. The controller
>> can operate in either command or memory mode. In memory mode
>> the Flash is exposed as normal memory and can be directly
>> accessed by the CPU.
>>
>> Signed-off-by: Joachim Eastwood <manabian@gmail.com>
>> ---
>>  drivers/mtd/spi-nor/Kconfig     |  10 +
>>  drivers/mtd/spi-nor/Makefile    |   1 +
>>  drivers/mtd/spi-nor/nxp-spifi.c | 508 ++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 519 insertions(+)
>>  create mode 100644 drivers/mtd/spi-nor/nxp-spifi.c
>>
>> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
>> index 64a4f0edabc7..f10a37f1a4ef 100644
>> --- a/drivers/mtd/spi-nor/Kconfig
>> +++ b/drivers/mtd/spi-nor/Kconfig
>> @@ -28,4 +28,14 @@ config SPI_FSL_QUADSPI
>>         This enables support for the Quad SPI controller in master mode.
>>         We only connect the NOR to this controller now.
>>
>> +config SPI_NXP_SPIFI
>> +     tristate "NXP SPI Flash Interface (SPIFI)"
>> +     depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
>
> Since you are adding COMPILE_TEST, maybe you want
> 'depends on HAS_IOMEM' as well?

Since MTD depends on GENERIC_IO is that needed?
Or am I confusing the config options here(?)

>> +static int nxp_spifi_wait_for_event(struct nxp_spifi *spifi, u32 event)
>> +{
>> +     int retry = 3;
>> +     u32 stat;
>> +
>> +     do {
>> +             stat = readb(spifi->io_base + SPIFI_STAT);
>> +             if (!(stat & event))
>> +                     return 0;
>> +
>> +             udelay(10);
>> +     } while (retry--);
>> +
>> +     return -ETIMEDOUT;
>
> This could be replaced with the readb_poll_timeout_atomic().
> But it seems you would also use readb_poll_timeout(), since won't be
> called in atomic context.

Didn't know about the readX_poll_timeout functions and does indeed
look usable. Thanks for the tip.


>> +static int nxp_spifi_set_memory_mode_on(struct nxp_spifi *spifi)
>> +{
>> +     int retry = 3;
>> +     u32 stat;
>> +
>> +     stat = readb(spifi->io_base + SPIFI_STAT);
>> +     if (stat & SPIFI_STAT_MCINIT)
>> +             return 0;
>
> Do you think it makes sense to cache the memory/command mode
> instead of reading it?

I think that's good idea.

>Would it affect throughput in any sense?

Maybe. It's done for every read/write operation so making it a bit
faster is good idea. I don't see any downsides to implement it the way
you suggest either.


> I'm thinking these slow-clocked microcontrollers might benefit from
> such tricks, but I don't have actual numbers to back this up.
>
>> +
>> +     writel(spifi->mcmd, spifi->io_base + SPIFI_MCMD);
>> +
>> +     do {
>> +             stat = readb(spifi->io_base + SPIFI_STAT);
>> +             if (stat & SPIFI_STAT_MCINIT)
>> +                     return 0;
>> +
>> +             udelay(10);
>> +     } while (retry--);
>
> Same here about using iopoll variants.

Yeah, got it.


>> +
>> +     dev_err(spifi->dev, "unable to enter memory mode\n");
>> +
>> +     return -ETIMEDOUT;
>> +}
>> +
>> +static int nxp_spifi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
>> +{
>> +     struct nxp_spifi *spifi = nor->priv;
>> +     u32 cmd;
>> +     int ret;
>> +
>> +     ret = nxp_spifi_set_memory_mode_off(spifi);
>> +     if (ret)
>> +             return ret;
>> +
>> +     cmd = SPIFI_CMD_DATALEN(len) |
>> +           SPIFI_CMD_OPCODE(opcode) |
>> +           SPIFI_CMD_FIELDFORM_ALL_SERIAL |
>> +           SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
>> +     writel(cmd, spifi->io_base + SPIFI_CMD);
>> +
>> +     while (len--)
>> +             *buf++  = readb(spifi->io_base + SPIFI_DATA);
>
> Nit: extra whitespace here.

Well spotted!


>> +static int nxp_spifi_probe(struct platform_device *pdev)
>> +{
>> +     struct device_node *flash_np;
>> +     struct nxp_spifi *spifi;
>> +     struct resource *res;
>> +     int ret;
>> +
>> +     spifi = devm_kzalloc(&pdev->dev, sizeof(*spifi), GFP_KERNEL);
>> +     if (!spifi)
>> +             return -ENOMEM;
>> +
>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "spifi");
>> +     spifi->io_base = devm_ioremap_resource(&pdev->dev, res);
>> +     if (IS_ERR(spifi->io_base))
>> +             return PTR_ERR(spifi->io_base);
>> +
>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "flash");
>> +     spifi->flash_base = devm_ioremap_resource(&pdev->dev, res);
>> +     if (IS_ERR(spifi->flash_base))
>> +             return PTR_ERR(spifi->flash_base);
>> +
>
> Just curious: is the memory mapping fixed?

On LPC43xx you can chose between two different mappings; 0x1400 0000
and 0x8000 0000

The first only support up 64 MB, as opposed to 128 MB for the second,
but is slightly faster according to the data sheet. See Table 444 in
the data sheet.

Other LPC families have different mappings as well.


Thanks for looking, Ezequiel.


regards,
Joachim Eastwood
Ezequiel Garcia May 30, 2015, 6:08 p.m. UTC | #3
+Richard

On 05/30/2015 01:51 PM, Joachim Eastwood wrote:
> Hi Ezequiel,
> 
> On 30 May 2015 at 17:43, Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> wrote:
>> Hi Joachim,
>>
>> Looks pretty neat. I've just a couple comments.
>>
>> On 05/29/2015 02:50 PM, Joachim Eastwood wrote:
>>> Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
>>> controller that is found newer NXP MCU devices.
>>>
>>> The controller supports serial SPI Flash devices with 1-, 2-
>>> and 4-bit width in either SPI mode 0 or 3. The controller
>>> can operate in either command or memory mode. In memory mode
>>> the Flash is exposed as normal memory and can be directly
>>> accessed by the CPU.
>>>
>>> Signed-off-by: Joachim Eastwood <manabian@gmail.com>
>>> ---
>>>  drivers/mtd/spi-nor/Kconfig     |  10 +
>>>  drivers/mtd/spi-nor/Makefile    |   1 +
>>>  drivers/mtd/spi-nor/nxp-spifi.c | 508 ++++++++++++++++++++++++++++++++++++++++
>>>  3 files changed, 519 insertions(+)
>>>  create mode 100644 drivers/mtd/spi-nor/nxp-spifi.c
>>>
>>> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
>>> index 64a4f0edabc7..f10a37f1a4ef 100644
>>> --- a/drivers/mtd/spi-nor/Kconfig
>>> +++ b/drivers/mtd/spi-nor/Kconfig
>>> @@ -28,4 +28,14 @@ config SPI_FSL_QUADSPI
>>>         This enables support for the Quad SPI controller in master mode.
>>>         We only connect the NOR to this controller now.
>>>
>>> +config SPI_NXP_SPIFI
>>> +     tristate "NXP SPI Flash Interface (SPIFI)"
>>> +     depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
>>
>> Since you are adding COMPILE_TEST, maybe you want
>> 'depends on HAS_IOMEM' as well?
> 
> Since MTD depends on GENERIC_IO is that needed?
> Or am I confusing the config options here(?)
> 

I think you need HAS_IOMEM for ioremap stuff.
Maybe Brian or Richard will know better.

>>> +static int nxp_spifi_wait_for_event(struct nxp_spifi *spifi, u32 event)
>>> +{
>>> +     int retry = 3;
>>> +     u32 stat;
>>> +
>>> +     do {
>>> +             stat = readb(spifi->io_base + SPIFI_STAT);
>>> +             if (!(stat & event))
>>> +                     return 0;
>>> +
>>> +             udelay(10);
>>> +     } while (retry--);
>>> +
>>> +     return -ETIMEDOUT;
>>
>> This could be replaced with the readb_poll_timeout_atomic().
>> But it seems you would also use readb_poll_timeout(), since won't be
>> called in atomic context.
> 
> Didn't know about the readX_poll_timeout functions and does indeed
> look usable. Thanks for the tip.
> 
> 
>>> +static int nxp_spifi_set_memory_mode_on(struct nxp_spifi *spifi)
>>> +{
>>> +     int retry = 3;
>>> +     u32 stat;
>>> +
>>> +     stat = readb(spifi->io_base + SPIFI_STAT);
>>> +     if (stat & SPIFI_STAT_MCINIT)
>>> +             return 0;
>>
>> Do you think it makes sense to cache the memory/command mode
>> instead of reading it?
> 
> I think that's good idea.
> 
>> Would it affect throughput in any sense?
> 
> Maybe. It's done for every read/write operation so making it a bit
> faster is good idea. I don't see any downsides to implement it the way
> you suggest either.
> 
> 
>> I'm thinking these slow-clocked microcontrollers might benefit from
>> such tricks, but I don't have actual numbers to back this up.
>>
>>> +
>>> +     writel(spifi->mcmd, spifi->io_base + SPIFI_MCMD);
>>> +
>>> +     do {
>>> +             stat = readb(spifi->io_base + SPIFI_STAT);
>>> +             if (stat & SPIFI_STAT_MCINIT)
>>> +                     return 0;
>>> +
>>> +             udelay(10);
>>> +     } while (retry--);
>>
>> Same here about using iopoll variants.
> 
> Yeah, got it.
> 
> 
>>> +
>>> +     dev_err(spifi->dev, "unable to enter memory mode\n");
>>> +
>>> +     return -ETIMEDOUT;
>>> +}
>>> +
>>> +static int nxp_spifi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
>>> +{
>>> +     struct nxp_spifi *spifi = nor->priv;
>>> +     u32 cmd;
>>> +     int ret;
>>> +
>>> +     ret = nxp_spifi_set_memory_mode_off(spifi);
>>> +     if (ret)
>>> +             return ret;
>>> +
>>> +     cmd = SPIFI_CMD_DATALEN(len) |
>>> +           SPIFI_CMD_OPCODE(opcode) |
>>> +           SPIFI_CMD_FIELDFORM_ALL_SERIAL |
>>> +           SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
>>> +     writel(cmd, spifi->io_base + SPIFI_CMD);
>>> +
>>> +     while (len--)
>>> +             *buf++  = readb(spifi->io_base + SPIFI_DATA);
>>
>> Nit: extra whitespace here.
> 
> Well spotted!
> 
> 
>>> +static int nxp_spifi_probe(struct platform_device *pdev)
>>> +{
>>> +     struct device_node *flash_np;
>>> +     struct nxp_spifi *spifi;
>>> +     struct resource *res;
>>> +     int ret;
>>> +
>>> +     spifi = devm_kzalloc(&pdev->dev, sizeof(*spifi), GFP_KERNEL);
>>> +     if (!spifi)
>>> +             return -ENOMEM;
>>> +
>>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "spifi");
>>> +     spifi->io_base = devm_ioremap_resource(&pdev->dev, res);
>>> +     if (IS_ERR(spifi->io_base))
>>> +             return PTR_ERR(spifi->io_base);
>>> +
>>> +     res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "flash");
>>> +     spifi->flash_base = devm_ioremap_resource(&pdev->dev, res);
>>> +     if (IS_ERR(spifi->flash_base))
>>> +             return PTR_ERR(spifi->flash_base);
>>> +
>>
>> Just curious: is the memory mapping fixed?
> 
> On LPC43xx you can chose between two different mappings; 0x1400 0000
> and 0x8000 0000
> 
> The first only support up 64 MB, as opposed to 128 MB for the second,
> but is slightly faster according to the data sheet. See Table 444 in
> the data sheet.
> 
> Other LPC families have different mappings as well.
> 

OK, so I guess the bootloader would be in charge of wiring this up and
updating the dtb - if needed.
Richard Weinberger May 30, 2015, 7:33 p.m. UTC | #4
Am 30.05.2015 um 20:08 schrieb Ezequiel Garcia:
> +Richard
> 
> On 05/30/2015 01:51 PM, Joachim Eastwood wrote:
>> Hi Ezequiel,
>>
>> On 30 May 2015 at 17:43, Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> wrote:
>>> Hi Joachim,
>>>
>>> Looks pretty neat. I've just a couple comments.
>>>
>>> On 05/29/2015 02:50 PM, Joachim Eastwood wrote:
>>>> Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
>>>> controller that is found newer NXP MCU devices.
>>>>
>>>> The controller supports serial SPI Flash devices with 1-, 2-
>>>> and 4-bit width in either SPI mode 0 or 3. The controller
>>>> can operate in either command or memory mode. In memory mode
>>>> the Flash is exposed as normal memory and can be directly
>>>> accessed by the CPU.
>>>>
>>>> Signed-off-by: Joachim Eastwood <manabian@gmail.com>
>>>> ---
>>>>  drivers/mtd/spi-nor/Kconfig     |  10 +
>>>>  drivers/mtd/spi-nor/Makefile    |   1 +
>>>>  drivers/mtd/spi-nor/nxp-spifi.c | 508 ++++++++++++++++++++++++++++++++++++++++
>>>>  3 files changed, 519 insertions(+)
>>>>  create mode 100644 drivers/mtd/spi-nor/nxp-spifi.c
>>>>
>>>> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
>>>> index 64a4f0edabc7..f10a37f1a4ef 100644
>>>> --- a/drivers/mtd/spi-nor/Kconfig
>>>> +++ b/drivers/mtd/spi-nor/Kconfig
>>>> @@ -28,4 +28,14 @@ config SPI_FSL_QUADSPI
>>>>         This enables support for the Quad SPI controller in master mode.
>>>>         We only connect the NOR to this controller now.
>>>>
>>>> +config SPI_NXP_SPIFI
>>>> +     tristate "NXP SPI Flash Interface (SPIFI)"
>>>> +     depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
>>>
>>> Since you are adding COMPILE_TEST, maybe you want
>>> 'depends on HAS_IOMEM' as well?
>>
>> Since MTD depends on GENERIC_IO is that needed?
>> Or am I confusing the config options here(?)
>>
> 
> I think you need HAS_IOMEM for ioremap stuff.
> Maybe Brian or Richard will know better.

Yes, if you need ioremap() your driver has to depend on HAS_IOMEM.

We have GENERIC_IO to allow non-physical MTD stuff
on architectures without io memory, namely s390 and UML.
Some time ago I've implemented GENERIC_IO to make nandsim
and UBI work on UML.

Thanks,
//richard
Ezequiel Garcia May 30, 2015, 7:37 p.m. UTC | #5
On 05/30/2015 04:37 PM, Joachim Eastwood wrote:
> On 30 May 2015 at 21:33, Richard Weinberger <richard@nod.at> wrote:
>> Am 30.05.2015 um 20:08 schrieb Ezequiel Garcia:
>>> +Richard
>>>
>>> On 05/30/2015 01:51 PM, Joachim Eastwood wrote:
>>>> Hi Ezequiel,
>>>>
>>>> On 30 May 2015 at 17:43, Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> wrote:
>>>>> Hi Joachim,
>>>>>
>>>>> Looks pretty neat. I've just a couple comments.
>>>>>
>>>>> On 05/29/2015 02:50 PM, Joachim Eastwood wrote:
>>>>>> Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
>>>>>> controller that is found newer NXP MCU devices.
>>>>>>
>>>>>> The controller supports serial SPI Flash devices with 1-, 2-
>>>>>> and 4-bit width in either SPI mode 0 or 3. The controller
>>>>>> can operate in either command or memory mode. In memory mode
>>>>>> the Flash is exposed as normal memory and can be directly
>>>>>> accessed by the CPU.
>>>>>>
>>>>>> Signed-off-by: Joachim Eastwood <manabian@gmail.com>
>>>>>> ---
>>>>>>  drivers/mtd/spi-nor/Kconfig     |  10 +
>>>>>>  drivers/mtd/spi-nor/Makefile    |   1 +
>>>>>>  drivers/mtd/spi-nor/nxp-spifi.c | 508 ++++++++++++++++++++++++++++++++++++++++
>>>>>>  3 files changed, 519 insertions(+)
>>>>>>  create mode 100644 drivers/mtd/spi-nor/nxp-spifi.c
>>>>>>
>>>>>> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
>>>>>> index 64a4f0edabc7..f10a37f1a4ef 100644
>>>>>> --- a/drivers/mtd/spi-nor/Kconfig
>>>>>> +++ b/drivers/mtd/spi-nor/Kconfig
>>>>>> @@ -28,4 +28,14 @@ config SPI_FSL_QUADSPI
>>>>>>         This enables support for the Quad SPI controller in master mode.
>>>>>>         We only connect the NOR to this controller now.
>>>>>>
>>>>>> +config SPI_NXP_SPIFI
>>>>>> +     tristate "NXP SPI Flash Interface (SPIFI)"
>>>>>> +     depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
>>>>>
>>>>> Since you are adding COMPILE_TEST, maybe you want
>>>>> 'depends on HAS_IOMEM' as well?
>>>>
>>>> Since MTD depends on GENERIC_IO is that needed?
>>>> Or am I confusing the config options here(?)
>>>>
>>>
>>> I think you need HAS_IOMEM for ioremap stuff.
>>> Maybe Brian or Richard will know better.
>>
>> Yes, if you need ioremap() your driver has to depend on HAS_IOMEM.
>>
>> We have GENERIC_IO to allow non-physical MTD stuff
>> on architectures without io memory, namely s390 and UML.
>> Some time ago I've implemented GENERIC_IO to make nandsim
>> and UBI work on UML.
> 
> Got it.
> Thanks Richard.
> 
> I'll send a new version of the patch within a couple of days.
> 

You can add my reviewed on that.

Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Joachim Eastwood May 30, 2015, 7:37 p.m. UTC | #6
On 30 May 2015 at 21:33, Richard Weinberger <richard@nod.at> wrote:
> Am 30.05.2015 um 20:08 schrieb Ezequiel Garcia:
>> +Richard
>>
>> On 05/30/2015 01:51 PM, Joachim Eastwood wrote:
>>> Hi Ezequiel,
>>>
>>> On 30 May 2015 at 17:43, Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> wrote:
>>>> Hi Joachim,
>>>>
>>>> Looks pretty neat. I've just a couple comments.
>>>>
>>>> On 05/29/2015 02:50 PM, Joachim Eastwood wrote:
>>>>> Add SPI-NOR driver for the SPI Flash Interface (SPIFI)
>>>>> controller that is found newer NXP MCU devices.
>>>>>
>>>>> The controller supports serial SPI Flash devices with 1-, 2-
>>>>> and 4-bit width in either SPI mode 0 or 3. The controller
>>>>> can operate in either command or memory mode. In memory mode
>>>>> the Flash is exposed as normal memory and can be directly
>>>>> accessed by the CPU.
>>>>>
>>>>> Signed-off-by: Joachim Eastwood <manabian@gmail.com>
>>>>> ---
>>>>>  drivers/mtd/spi-nor/Kconfig     |  10 +
>>>>>  drivers/mtd/spi-nor/Makefile    |   1 +
>>>>>  drivers/mtd/spi-nor/nxp-spifi.c | 508 ++++++++++++++++++++++++++++++++++++++++
>>>>>  3 files changed, 519 insertions(+)
>>>>>  create mode 100644 drivers/mtd/spi-nor/nxp-spifi.c
>>>>>
>>>>> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
>>>>> index 64a4f0edabc7..f10a37f1a4ef 100644
>>>>> --- a/drivers/mtd/spi-nor/Kconfig
>>>>> +++ b/drivers/mtd/spi-nor/Kconfig
>>>>> @@ -28,4 +28,14 @@ config SPI_FSL_QUADSPI
>>>>>         This enables support for the Quad SPI controller in master mode.
>>>>>         We only connect the NOR to this controller now.
>>>>>
>>>>> +config SPI_NXP_SPIFI
>>>>> +     tristate "NXP SPI Flash Interface (SPIFI)"
>>>>> +     depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
>>>>
>>>> Since you are adding COMPILE_TEST, maybe you want
>>>> 'depends on HAS_IOMEM' as well?
>>>
>>> Since MTD depends on GENERIC_IO is that needed?
>>> Or am I confusing the config options here(?)
>>>
>>
>> I think you need HAS_IOMEM for ioremap stuff.
>> Maybe Brian or Richard will know better.
>
> Yes, if you need ioremap() your driver has to depend on HAS_IOMEM.
>
> We have GENERIC_IO to allow non-physical MTD stuff
> on architectures without io memory, namely s390 and UML.
> Some time ago I've implemented GENERIC_IO to make nandsim
> and UBI work on UML.

Got it.
Thanks Richard.

I'll send a new version of the patch within a couple of days.


regards,
Joachim Eastwood
diff mbox

Patch

diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
index 64a4f0edabc7..f10a37f1a4ef 100644
--- a/drivers/mtd/spi-nor/Kconfig
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -28,4 +28,14 @@  config SPI_FSL_QUADSPI
 	  This enables support for the Quad SPI controller in master mode.
 	  We only connect the NOR to this controller now.
 
+config SPI_NXP_SPIFI
+	tristate "NXP SPI Flash Interface (SPIFI)"
+	depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
+	help
+	  Enable support for the NXP LPC SPI Flash Interface controller.
+
+	  SPIFI is a specialized controller for connecting serial SPI
+	  Flash. Enable this option if you have a device with a SPIFI
+	  controller and want to access the Flash as a mtd device.
+
 endif # MTD_SPI_NOR
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index 6a7ce1462247..e53333ef8582 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -1,2 +1,3 @@ 
 obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
 obj-$(CONFIG_SPI_FSL_QUADSPI)	+= fsl-quadspi.o
+obj-$(CONFIG_SPI_NXP_SPIFI)	+= nxp-spifi.o
diff --git a/drivers/mtd/spi-nor/nxp-spifi.c b/drivers/mtd/spi-nor/nxp-spifi.c
new file mode 100644
index 000000000000..cbfe0bb16f81
--- /dev/null
+++ b/drivers/mtd/spi-nor/nxp-spifi.c
@@ -0,0 +1,508 @@ 
+/*
+ * SPI-NOR driver for NXP SPI Flash Interface (SPIFI)
+ *
+ * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
+ *
+ * Based on Freescale QuadSPI driver:
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/spi-nor.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+/* NXP SPIFI registers, bits and macros */
+#define SPIFI_CTRL				0x000
+#define  SPIFI_CTRL_TIMEOUT(timeout)		(timeout)
+#define  SPIFI_CTRL_CSHIGH(cshigh)		((cshigh) << 16)
+#define  SPIFI_CTRL_MODE3			BIT(23)
+#define  SPIFI_CTRL_DUAL			BIT(28)
+#define  SPIFI_CTRL_FBCLK			BIT(30)
+#define SPIFI_CMD				0x004
+#define  SPIFI_CMD_DATALEN(dlen)		(dlen & 0x3fff)
+#define  SPIFI_CMD_DOUT				BIT(15)
+#define  SPIFI_CMD_INTLEN(ilen)			((ilen) << 16)
+#define  SPIFI_CMD_FIELDFORM(field)		((field) << 19)
+#define  SPIFI_CMD_FIELDFORM_ALL_SERIAL		SPIFI_CMD_FIELDFORM(0x0)
+#define  SPIFI_CMD_FIELDFORM_QUAD_DUAL_DATA	SPIFI_CMD_FIELDFORM(0x1)
+#define  SPIFI_CMD_FRAMEFORM(frame)		((frame) << 21)
+#define  SPIFI_CMD_FRAMEFORM_OPCODE_ONLY	SPIFI_CMD_FRAMEFORM(0x1)
+#define  SPIFI_CMD_OPCODE(op)			((op) << 24)
+#define SPIFI_ADDR				0x008
+#define SPIFI_IDATA				0x00c
+#define SPIFI_CLIMIT				0x010
+#define SPIFI_DATA				0x014
+#define SPIFI_MCMD				0x018
+#define SPIFI_STAT				0x01c
+#define  SPIFI_STAT_MCINIT			BIT(0)
+#define  SPIFI_STAT_CMD				BIT(1)
+#define  SPIFI_STAT_RESET			BIT(4)
+
+#define SPI_NOR_MAX_ID_LEN	6
+
+struct nxp_spifi {
+	struct device *dev;
+	struct clk *clk_spifi;
+	struct clk *clk_reg;
+	void __iomem *io_base;
+	void __iomem *flash_base;
+	struct mtd_info mtd;
+	struct spi_nor nor;
+	u32 mcmd;
+};
+
+static int nxp_spifi_wait_for_event(struct nxp_spifi *spifi, u32 event)
+{
+	int retry = 3;
+	u32 stat;
+
+	do {
+		stat = readb(spifi->io_base + SPIFI_STAT);
+		if (!(stat & event))
+			return 0;
+
+		udelay(10);
+	} while (retry--);
+
+	return -ETIMEDOUT;
+}
+
+static int nxp_spifi_wait_for_cmd(struct nxp_spifi *spifi)
+{
+	int ret;
+
+	ret = nxp_spifi_wait_for_event(spifi, SPIFI_STAT_CMD);
+	if (ret)
+		dev_warn(spifi->dev, "command timed out\n");
+
+	return ret;
+}
+
+static int nxp_spifi_reset(struct nxp_spifi *spifi)
+{
+	int ret;
+
+	writel(SPIFI_STAT_RESET, spifi->io_base + SPIFI_STAT);
+	ret = nxp_spifi_wait_for_event(spifi, SPIFI_STAT_RESET);
+	if (ret)
+		dev_warn(spifi->dev, "state reset timed out\n");
+
+	return ret;
+}
+
+static int nxp_spifi_set_memory_mode_off(struct nxp_spifi *spifi)
+{
+	u32 stat;
+	int ret;
+
+	stat = readb(spifi->io_base + SPIFI_STAT);
+	if (!(stat & SPIFI_STAT_MCINIT))
+		return 0;
+
+	ret = nxp_spifi_reset(spifi);
+	if (ret)
+		dev_err(spifi->dev, "unable to enter command mode\n");
+
+	return ret;
+}
+
+static int nxp_spifi_set_memory_mode_on(struct nxp_spifi *spifi)
+{
+	int retry = 3;
+	u32 stat;
+
+	stat = readb(spifi->io_base + SPIFI_STAT);
+	if (stat & SPIFI_STAT_MCINIT)
+		return 0;
+
+	writel(spifi->mcmd, spifi->io_base + SPIFI_MCMD);
+
+	do {
+		stat = readb(spifi->io_base + SPIFI_STAT);
+		if (stat & SPIFI_STAT_MCINIT)
+			return 0;
+
+		udelay(10);
+	} while (retry--);
+
+	dev_err(spifi->dev, "unable to enter memory mode\n");
+
+	return -ETIMEDOUT;
+}
+
+static int nxp_spifi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
+{
+	struct nxp_spifi *spifi = nor->priv;
+	u32 cmd;
+	int ret;
+
+	ret = nxp_spifi_set_memory_mode_off(spifi);
+	if (ret)
+		return ret;
+
+	cmd = SPIFI_CMD_DATALEN(len) |
+	      SPIFI_CMD_OPCODE(opcode) |
+	      SPIFI_CMD_FIELDFORM_ALL_SERIAL |
+	      SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
+	writel(cmd, spifi->io_base + SPIFI_CMD);
+
+	while (len--)
+		*buf++  = readb(spifi->io_base + SPIFI_DATA);
+
+	return nxp_spifi_wait_for_cmd(spifi);
+}
+
+static int nxp_spifi_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
+			       int len, int write_enable)
+{
+	struct nxp_spifi *spifi = nor->priv;
+	u32 cmd;
+	int ret;
+
+	ret = nxp_spifi_set_memory_mode_off(spifi);
+	if (ret)
+		return ret;
+
+	cmd = SPIFI_CMD_DOUT |
+	      SPIFI_CMD_DATALEN(len) |
+	      SPIFI_CMD_OPCODE(opcode) |
+	      SPIFI_CMD_FIELDFORM_ALL_SERIAL |
+	      SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
+	writel(cmd, spifi->io_base + SPIFI_CMD);
+
+	while (len--)
+		writeb(*buf++, spifi->io_base + SPIFI_DATA);
+
+	return nxp_spifi_wait_for_cmd(spifi);
+}
+
+static int nxp_spifi_read(struct spi_nor *nor, loff_t from, size_t len,
+			  size_t *retlen, u_char *buf)
+{
+	struct nxp_spifi *spifi = nor->priv;
+	int ret;
+
+	ret = nxp_spifi_set_memory_mode_on(spifi);
+	if (ret)
+		return ret;
+
+	memcpy_fromio(buf, spifi->flash_base + from, len);
+	*retlen += len;
+
+	return 0;
+}
+
+static void nxp_spifi_write(struct spi_nor *nor, loff_t to, size_t len,
+			    size_t *retlen, const u_char *buf)
+{
+	struct nxp_spifi *spifi = nor->priv;
+	u32 cmd;
+	int ret;
+
+	ret = nxp_spifi_set_memory_mode_off(spifi);
+	if (ret) {
+		*retlen = 0;
+		return;
+	}
+
+	writel(to, spifi->io_base + SPIFI_ADDR);
+	*retlen = len;
+
+	cmd = SPIFI_CMD_DOUT |
+	      SPIFI_CMD_DATALEN(len) |
+	      SPIFI_CMD_FIELDFORM_ALL_SERIAL |
+	      SPIFI_CMD_OPCODE(nor->program_opcode) |
+	      SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
+	writel(cmd, spifi->io_base + SPIFI_CMD);
+
+	while (len--)
+		writeb(*buf++, spifi->io_base + SPIFI_DATA);
+
+	nxp_spifi_wait_for_cmd(spifi);
+}
+
+static int nxp_spifi_erase(struct spi_nor *nor, loff_t offs)
+{
+	struct nxp_spifi *spifi = nor->priv;
+	u32 cmd;
+	int ret;
+
+	ret = nxp_spifi_set_memory_mode_off(spifi);
+	if (ret)
+		return ret;
+
+	writel(offs, spifi->io_base + SPIFI_ADDR);
+
+	cmd = SPIFI_CMD_FIELDFORM_ALL_SERIAL |
+	      SPIFI_CMD_OPCODE(nor->erase_opcode) |
+	      SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
+	writel(cmd, spifi->io_base + SPIFI_CMD);
+
+	return nxp_spifi_wait_for_cmd(spifi);
+}
+
+static int nxp_spifi_setup_memory_cmd(struct nxp_spifi *spifi)
+{
+	switch (spifi->nor.flash_read) {
+	case SPI_NOR_NORMAL:
+	case SPI_NOR_FAST:
+		spifi->mcmd = SPIFI_CMD_FIELDFORM_ALL_SERIAL;
+		break;
+	case SPI_NOR_DUAL:
+	case SPI_NOR_QUAD:
+		spifi->mcmd = SPIFI_CMD_FIELDFORM_QUAD_DUAL_DATA;
+		break;
+	default:
+		dev_err(spifi->dev, "unsupported spi read mode\n");
+		return -EINVAL;
+	}
+
+	/* Memory mode supports address length between 1 and 4 */
+	if (spifi->nor.addr_width < 1 || spifi->nor.addr_width > 4)
+		return -EINVAL;
+
+	spifi->mcmd |= SPIFI_CMD_OPCODE(spifi->nor.read_opcode) |
+		       SPIFI_CMD_INTLEN(spifi->nor.read_dummy / 8) |
+		       SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
+
+	return 0;
+}
+
+static void nxp_spifi_dummy_id_read(struct spi_nor *nor)
+{
+	u8 id[SPI_NOR_MAX_ID_LEN];
+	nor->read_reg(nor, SPINOR_OP_RDID, id, SPI_NOR_MAX_ID_LEN);
+}
+
+static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
+				 struct device_node *np)
+{
+	struct mtd_part_parser_data ppdata;
+	enum read_mode flash_read;
+	u32 ctrl, property;
+	char modalias[40];
+	u16 mode = 0;
+	int ret;
+
+	if (!of_property_read_u32(np, "spi-rx-bus-width", &property)) {
+		switch (property) {
+		case 1:
+			break;
+		case 2:
+			mode |= SPI_RX_DUAL;
+			break;
+		case 4:
+			mode |= SPI_RX_QUAD;
+			break;
+		default:
+			dev_err(spifi->dev, "unsupported rx-bus-width\n");
+			return -EINVAL;
+		}
+	}
+
+	if (of_find_property(np, "spi-cpha", NULL))
+		mode |= SPI_CPHA;
+
+	if (of_find_property(np, "spi-cpol", NULL))
+		mode |= SPI_CPOL;
+
+	/* Setup control register defaults */
+	ctrl = SPIFI_CTRL_TIMEOUT(1000) |
+	       SPIFI_CTRL_CSHIGH(15) |
+	       SPIFI_CTRL_FBCLK;
+
+	if (mode & SPI_RX_DUAL) {
+		ctrl |= SPIFI_CTRL_DUAL;
+		flash_read = SPI_NOR_DUAL;
+	} else if (mode & SPI_RX_QUAD) {
+		ctrl &= ~SPIFI_CTRL_DUAL;
+		flash_read = SPI_NOR_QUAD;
+	} else {
+		ctrl |= SPIFI_CTRL_DUAL;
+		flash_read = SPI_NOR_NORMAL;
+	}
+
+	switch (mode & (SPI_CPHA | SPI_CPOL)) {
+	case SPI_MODE_0:
+		ctrl &= ~SPIFI_CTRL_MODE3;
+		break;
+	case SPI_MODE_3:
+		ctrl |= SPIFI_CTRL_MODE3;
+		break;
+	default:
+		dev_err(spifi->dev, "only mode 0 and 3 supported\n");
+		return -EINVAL;
+	}
+
+	writel(ctrl, spifi->io_base + SPIFI_CTRL);
+	dev_info(spifi->dev, "spifi ctrl = 0x%08x\n", ctrl);
+
+	spifi->mtd.priv  = &spifi->nor;
+	spifi->nor.mtd   = &spifi->mtd;
+	spifi->nor.dev   = spifi->dev;
+	spifi->nor.priv  = spifi;
+	spifi->nor.read  = nxp_spifi_read;
+	spifi->nor.write = nxp_spifi_write;
+	spifi->nor.erase = nxp_spifi_erase;
+	spifi->nor.read_reg  = nxp_spifi_read_reg;
+	spifi->nor.write_reg = nxp_spifi_write_reg;
+
+	ret = of_modalias_node(np, modalias, sizeof(modalias));
+	if (ret < 0) {
+		dev_err(spifi->dev, "unable to get device modalias\n");
+		return ret;
+	}
+
+	/*
+	 * The first read on a hard reset isn't reliable so do a
+	 * dummy read of the id before calling spi_nor_scan().
+	 * The reason for this problem is unknown.
+	 *
+	 * The official NXP spifilib uses more or less the same
+	 * workaround that is applied here by reading the device
+	 * id multiple times.
+	 */
+	nxp_spifi_dummy_id_read(&spifi->nor);
+
+	ret = spi_nor_scan(&spifi->nor, modalias, flash_read);
+	if (ret) {
+		dev_err(spifi->dev, "device scan failed\n");
+		return ret;
+	}
+
+	ret = nxp_spifi_setup_memory_cmd(spifi);
+	if (ret) {
+		dev_err(spifi->dev, "memory command setup failed\n");
+		return ret;
+	}
+
+	ppdata.of_node = np;
+	ret = mtd_device_parse_register(&spifi->mtd, NULL, &ppdata, NULL, 0);
+	if (ret) {
+		dev_err(spifi->dev, "mtd device parse failed\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int nxp_spifi_probe(struct platform_device *pdev)
+{
+	struct device_node *flash_np;
+	struct nxp_spifi *spifi;
+	struct resource *res;
+	int ret;
+
+	spifi = devm_kzalloc(&pdev->dev, sizeof(*spifi), GFP_KERNEL);
+	if (!spifi)
+		return -ENOMEM;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "spifi");
+	spifi->io_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(spifi->io_base))
+		return PTR_ERR(spifi->io_base);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "flash");
+	spifi->flash_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(spifi->flash_base))
+		return PTR_ERR(spifi->flash_base);
+
+	spifi->clk_spifi = devm_clk_get(&pdev->dev, "spifi");
+	if (IS_ERR(spifi->clk_spifi)) {
+		dev_err(&pdev->dev, "spifi clock not found\n");
+		return PTR_ERR(spifi->clk_spifi);
+	}
+
+	spifi->clk_reg = devm_clk_get(&pdev->dev, "reg");
+	if (IS_ERR(spifi->clk_reg)) {
+		dev_err(&pdev->dev, "reg clock not found\n");
+		return PTR_ERR(spifi->clk_reg);
+	}
+
+	ret = clk_prepare_enable(spifi->clk_reg);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to enable reg clock\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(spifi->clk_spifi);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to enable spifi clock\n");
+		goto dis_clk_reg;
+	}
+
+	spifi->dev = &pdev->dev;
+	platform_set_drvdata(pdev, spifi);
+
+	/* Initialize and reset device */
+	nxp_spifi_reset(spifi);
+	writel(0, spifi->io_base + SPIFI_IDATA);
+	writel(0, spifi->io_base + SPIFI_MCMD);
+	nxp_spifi_reset(spifi);
+
+	flash_np = of_get_next_available_child(pdev->dev.of_node, NULL);
+	if (!flash_np) {
+		dev_err(&pdev->dev, "no spi flash device to configure\n");
+		ret = -ENODEV;
+		goto dis_clks;
+	}
+
+	ret = nxp_spifi_setup_flash(spifi, flash_np);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to setup flash chip\n");
+		goto dis_clks;
+	}
+
+	return 0;
+
+dis_clks:
+	clk_disable_unprepare(spifi->clk_spifi);
+dis_clk_reg:
+	clk_disable_unprepare(spifi->clk_reg);
+	return ret;
+}
+
+static int nxp_spifi_remove(struct platform_device *pdev)
+{
+	struct nxp_spifi *spifi = platform_get_drvdata(pdev);
+
+	mtd_device_unregister(&spifi->mtd);
+	clk_disable_unprepare(spifi->clk_spifi);
+	clk_disable_unprepare(spifi->clk_reg);
+
+	return 0;
+}
+
+static const struct of_device_id nxp_spifi_match[] = {
+	{.compatible = "nxp,lpc1773-spifi"},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, nxp_spifi_match);
+
+static struct platform_driver nxp_spifi_driver = {
+	.probe	= nxp_spifi_probe,
+	.remove	= nxp_spifi_remove,
+	.driver	= {
+		.name = "nxp-spifi",
+		.of_match_table = nxp_spifi_match,
+	},
+};
+module_platform_driver(nxp_spifi_driver);
+
+MODULE_DESCRIPTION("NXP SPI Flash Interface driver");
+MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>");
+MODULE_LICENSE("GPL v2");