mtd: rawnand: Drop obsolete JZ4740 NAND driver

# SPDX-License-Identifier: GPL-2.0-only

config MTD_NAND_JZ4740

	tristate "JZ4740 NAND controller"

	depends on MACH_JZ4740 || COMPILE_TEST

	depends on HAS_IOMEM

	help

	  Enables support for NAND Flash on JZ4740 SoC based boards.

config MTD_NAND_JZ4780

	tristate "JZ4780 NAND controller"

	depends on JZ4780_NEMC

# SPDX-License-Identifier: GPL-2.0-only

obj-$(CONFIG_MTD_NAND_JZ4740) += jz4740_nand.o

obj-$(CONFIG_MTD_NAND_JZ4780) += ingenic_nand.o

ingenic_nand-y += ingenic_nand_drv.o

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>

 *  JZ4740 SoC NAND controller driver

 */

#include <linux/io.h>

#include <linux/ioport.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/slab.h>

#include <linux/mtd/mtd.h>

#include <linux/mtd/rawnand.h>

#include <linux/mtd/partitions.h>

#include <linux/gpio/consumer.h>

#include <linux/platform_data/jz4740/jz4740_nand.h>

#define JZ_REG_NAND_CTRL	0x50

#define JZ_REG_NAND_ECC_CTRL	0x100

#define JZ_REG_NAND_DATA	0x104

#define JZ_REG_NAND_PAR0	0x108

#define JZ_REG_NAND_PAR1	0x10C

#define JZ_REG_NAND_PAR2	0x110

#define JZ_REG_NAND_IRQ_STAT	0x114

#define JZ_REG_NAND_IRQ_CTRL	0x118

#define JZ_REG_NAND_ERR(x)	(0x11C + ((x) << 2))

#define JZ_NAND_ECC_CTRL_PAR_READY	BIT(4)

#define JZ_NAND_ECC_CTRL_ENCODING	BIT(3)

#define JZ_NAND_ECC_CTRL_RS		BIT(2)

#define JZ_NAND_ECC_CTRL_RESET		BIT(1)

#define JZ_NAND_ECC_CTRL_ENABLE		BIT(0)

#define JZ_NAND_STATUS_ERR_COUNT	(BIT(31) | BIT(30) | BIT(29))

#define JZ_NAND_STATUS_PAD_FINISH	BIT(4)

#define JZ_NAND_STATUS_DEC_FINISH	BIT(3)

#define JZ_NAND_STATUS_ENC_FINISH	BIT(2)

#define JZ_NAND_STATUS_UNCOR_ERROR	BIT(1)

#define JZ_NAND_STATUS_ERROR		BIT(0)

#define JZ_NAND_CTRL_ENABLE_CHIP(x) BIT((x) << 1)

#define JZ_NAND_CTRL_ASSERT_CHIP(x) BIT(((x) << 1) + 1)

#define JZ_NAND_CTRL_ASSERT_CHIP_MASK 0xaa

#define JZ_NAND_MEM_CMD_OFFSET 0x08000

#define JZ_NAND_MEM_ADDR_OFFSET 0x10000

struct jz_nand {

	struct nand_chip chip;

	void __iomem *base;

	struct resource *mem;

	unsigned char banks[JZ_NAND_NUM_BANKS];

	void __iomem *bank_base[JZ_NAND_NUM_BANKS];

	struct resource *bank_mem[JZ_NAND_NUM_BANKS];

	int selected_bank;

	struct gpio_desc *busy_gpio;

	bool is_reading;

};

static inline struct jz_nand *mtd_to_jz_nand(struct mtd_info *mtd)

{

	return container_of(mtd_to_nand(mtd), struct jz_nand, chip);

}

static void jz_nand_select_chip(struct nand_chip *chip, int chipnr)

{

	struct jz_nand *nand = mtd_to_jz_nand(nand_to_mtd(chip));

	uint32_t ctrl;

	int banknr;

	ctrl = readl(nand->base + JZ_REG_NAND_CTRL);

	ctrl &= ~JZ_NAND_CTRL_ASSERT_CHIP_MASK;

	if (chipnr == -1) {

		banknr = -1;

	} else {

		banknr = nand->banks[chipnr] - 1;

		chip->legacy.IO_ADDR_R = nand->bank_base[banknr];

		chip->legacy.IO_ADDR_W = nand->bank_base[banknr];

	}

	writel(ctrl, nand->base + JZ_REG_NAND_CTRL);

	nand->selected_bank = banknr;

}

static void jz_nand_cmd_ctrl(struct nand_chip *chip, int dat,

			     unsigned int ctrl)

{

	struct jz_nand *nand = mtd_to_jz_nand(nand_to_mtd(chip));

	uint32_t reg;

	void __iomem *bank_base = nand->bank_base[nand->selected_bank];

	BUG_ON(nand->selected_bank < 0);

	if (ctrl & NAND_CTRL_CHANGE) {

		BUG_ON((ctrl & NAND_ALE) && (ctrl & NAND_CLE));

		if (ctrl & NAND_ALE)

			bank_base += JZ_NAND_MEM_ADDR_OFFSET;

		else if (ctrl & NAND_CLE)

			bank_base += JZ_NAND_MEM_CMD_OFFSET;

		chip->legacy.IO_ADDR_W = bank_base;

		reg = readl(nand->base + JZ_REG_NAND_CTRL);

		if (ctrl & NAND_NCE)

			reg |= JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank);

		else

			reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank);

		writel(reg, nand->base + JZ_REG_NAND_CTRL);

	}

	if (dat != NAND_CMD_NONE)

		writeb(dat, chip->legacy.IO_ADDR_W);

}

static int jz_nand_dev_ready(struct nand_chip *chip)

{

	struct jz_nand *nand = mtd_to_jz_nand(nand_to_mtd(chip));

	return gpiod_get_value_cansleep(nand->busy_gpio);

}

static void jz_nand_hwctl(struct nand_chip *chip, int mode)

{

	struct jz_nand *nand = mtd_to_jz_nand(nand_to_mtd(chip));

	uint32_t reg;

	writel(0, nand->base + JZ_REG_NAND_IRQ_STAT);

	reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);

	reg |= JZ_NAND_ECC_CTRL_RESET;

	reg |= JZ_NAND_ECC_CTRL_ENABLE;

	reg |= JZ_NAND_ECC_CTRL_RS;

	switch (mode) {

	case NAND_ECC_READ:

		reg &= ~JZ_NAND_ECC_CTRL_ENCODING;

		nand->is_reading = true;

		break;

	case NAND_ECC_WRITE:

		reg |= JZ_NAND_ECC_CTRL_ENCODING;

		nand->is_reading = false;

		break;

	default:

		break;

	}

	writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);

}

static int jz_nand_calculate_ecc_rs(struct nand_chip *chip, const uint8_t *dat,

				    uint8_t *ecc_code)

{

	struct jz_nand *nand = mtd_to_jz_nand(nand_to_mtd(chip));

	uint32_t reg, status;

	int i;

	unsigned int timeout = 1000;

	static uint8_t empty_block_ecc[] = {0xcd, 0x9d, 0x90, 0x58, 0xf4,

						0x8b, 0xff, 0xb7, 0x6f};

	if (nand->is_reading)

		return 0;

	do {

		status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);

	} while (!(status & JZ_NAND_STATUS_ENC_FINISH) && --timeout);

	if (timeout == 0)

	    return -1;

	reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);

	reg &= ~JZ_NAND_ECC_CTRL_ENABLE;

	writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);

	for (i = 0; i < 9; ++i)

		ecc_code[i] = readb(nand->base + JZ_REG_NAND_PAR0 + i);

	/* If the written data is completly 0xff, we also want to write 0xff as

	 * ecc, otherwise we will get in trouble when doing subpage writes. */

	if (memcmp(ecc_code, empty_block_ecc, 9) == 0)

		memset(ecc_code, 0xff, 9);

	return 0;

}

static void jz_nand_correct_data(uint8_t *dat, int index, int mask)

{

	int offset = index & 0x7;

	uint16_t data;

	index += (index >> 3);

	data = dat[index];

	data |= dat[index+1] << 8;

	mask ^= (data >> offset) & 0x1ff;

	data &= ~(0x1ff << offset);

	data |= (mask << offset);

	dat[index] = data & 0xff;

	dat[index+1] = (data >> 8) & 0xff;

}

static int jz_nand_correct_ecc_rs(struct nand_chip *chip, uint8_t *dat,

				  uint8_t *read_ecc, uint8_t *calc_ecc)

{

	struct jz_nand *nand = mtd_to_jz_nand(nand_to_mtd(chip));

	int i, error_count, index;

	uint32_t reg, status, error;

	unsigned int timeout = 1000;

	for (i = 0; i < 9; ++i)

		writeb(read_ecc[i], nand->base + JZ_REG_NAND_PAR0 + i);

	reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);

	reg |= JZ_NAND_ECC_CTRL_PAR_READY;

	writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);

	do {

		status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);

	} while (!(status & JZ_NAND_STATUS_DEC_FINISH) && --timeout);

	if (timeout == 0)

		return -ETIMEDOUT;

	reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);

	reg &= ~JZ_NAND_ECC_CTRL_ENABLE;

	writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);

	if (status & JZ_NAND_STATUS_ERROR) {

		if (status & JZ_NAND_STATUS_UNCOR_ERROR)

			return -EBADMSG;

		error_count = (status & JZ_NAND_STATUS_ERR_COUNT) >> 29;

		for (i = 0; i < error_count; ++i) {

			error = readl(nand->base + JZ_REG_NAND_ERR(i));

			index = ((error >> 16) & 0x1ff) - 1;

			if (index >= 0 && index < 512)

				jz_nand_correct_data(dat, index, error & 0x1ff);

		}

		return error_count;

	}

	return 0;

}

static int jz_nand_ioremap_resource(struct platform_device *pdev,

	const char *name, struct resource **res, void __iomem **base)

{

	int ret;

	*res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);

	if (!*res) {

		dev_err(&pdev->dev, "Failed to get platform %s memory\n", name);

		ret = -ENXIO;

		goto err;

	}

	*res = request_mem_region((*res)->start, resource_size(*res),

				pdev->name);

	if (!*res) {

		dev_err(&pdev->dev, "Failed to request %s memory region\n", name);

		ret = -EBUSY;

		goto err;

	}

	*base = ioremap((*res)->start, resource_size(*res));

	if (!*base) {

		dev_err(&pdev->dev, "Failed to ioremap %s memory region\n", name);

		ret = -EBUSY;

		goto err_release_mem;

	}

	return 0;

err_release_mem:

	release_mem_region((*res)->start, resource_size(*res));

err:

	*res = NULL;

	*base = NULL;

	return ret;

}

static inline void jz_nand_iounmap_resource(struct resource *res,

					    void __iomem *base)

{

	iounmap(base);

	release_mem_region(res->start, resource_size(res));

}

static int jz_nand_detect_bank(struct platform_device *pdev,

			       struct jz_nand *nand, unsigned char bank,

			       size_t chipnr, uint8_t *nand_maf_id,

			       uint8_t *nand_dev_id)

{

	int ret;

	char res_name[6];

	uint32_t ctrl;

	struct nand_chip *chip = &nand->chip;

	struct mtd_info *mtd = nand_to_mtd(chip);

	struct nand_memory_organization *memorg;

	u8 id[2];

	memorg = nanddev_get_memorg(&chip->base);

	/* Request I/O resource. */

	sprintf(res_name, "bank%d", bank);

	ret = jz_nand_ioremap_resource(pdev, res_name,

					&nand->bank_mem[bank - 1],

					&nand->bank_base[bank - 1]);

	if (ret)

		return ret;

	/* Enable chip in bank. */

	ctrl = readl(nand->base + JZ_REG_NAND_CTRL);

	ctrl |= JZ_NAND_CTRL_ENABLE_CHIP(bank - 1);

	writel(ctrl, nand->base + JZ_REG_NAND_CTRL);

	if (chipnr == 0) {

		/* Detect first chip. */

		ret = nand_scan(chip, 1);

		if (ret)

			goto notfound_id;

		/* Retrieve the IDs from the first chip. */

		nand_select_target(chip, 0);

		nand_reset_op(chip);

		nand_readid_op(chip, 0, id, sizeof(id));

		*nand_maf_id = id[0];

		*nand_dev_id = id[1];

	} else {

		/* Detect additional chip. */

		nand_select_target(chip, chipnr);

		nand_reset_op(chip);

		nand_readid_op(chip, 0, id, sizeof(id));

		if (*nand_maf_id != id[0] || *nand_dev_id != id[1]) {

			ret = -ENODEV;

			goto notfound_id;

		}

		/* Update size of the MTD. */

		memorg->ntargets++;

		mtd->size += nanddev_target_size(&chip->base);

	}

	dev_info(&pdev->dev, "Found chip %zu on bank %i\n", chipnr, bank);

	return 0;

notfound_id:

	dev_info(&pdev->dev, "No chip found on bank %i\n", bank);

	ctrl &= ~(JZ_NAND_CTRL_ENABLE_CHIP(bank - 1));

	writel(ctrl, nand->base + JZ_REG_NAND_CTRL);

	jz_nand_iounmap_resource(nand->bank_mem[bank - 1],

				 nand->bank_base[bank - 1]);

	return ret;

}

static int jz_nand_attach_chip(struct nand_chip *chip)

{

	struct mtd_info *mtd = nand_to_mtd(chip);

	struct device *dev = mtd->dev.parent;

	struct jz_nand_platform_data *pdata = dev_get_platdata(dev);

	struct platform_device *pdev = to_platform_device(dev);

	if (pdata && pdata->ident_callback)

		pdata->ident_callback(pdev, mtd, &pdata->partitions,

				      &pdata->num_partitions);

	return 0;

}

static const struct nand_controller_ops jz_nand_controller_ops = {

	.attach_chip = jz_nand_attach_chip,

};

static int jz_nand_probe(struct platform_device *pdev)

{

	int ret;

	struct jz_nand *nand;

	struct nand_chip *chip;

	struct mtd_info *mtd;

	struct jz_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);

	size_t chipnr, bank_idx;

	uint8_t nand_maf_id = 0, nand_dev_id = 0;

	nand = kzalloc(sizeof(*nand), GFP_KERNEL);

	if (!nand)

		return -ENOMEM;

	ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);

	if (ret)

		goto err_free;

	nand->busy_gpio = devm_gpiod_get_optional(&pdev->dev, "busy", GPIOD_IN);

	if (IS_ERR(nand->busy_gpio)) {

		ret = PTR_ERR(nand->busy_gpio);

		dev_err(&pdev->dev, "Failed to request busy gpio %d\n",

		    ret);

		goto err_iounmap_mmio;

	}

	chip		= &nand->chip;

	mtd		= nand_to_mtd(chip);

	mtd->dev.parent = &pdev->dev;

	mtd->name	= "jz4740-nand";

	chip->ecc.hwctl		= jz_nand_hwctl;

	chip->ecc.calculate	= jz_nand_calculate_ecc_rs;

	chip->ecc.correct	= jz_nand_correct_ecc_rs;

	chip->ecc.mode		= NAND_ECC_HW_OOB_FIRST;

	chip->ecc.size		= 512;

	chip->ecc.bytes		= 9;

	chip->ecc.strength	= 4;

	chip->ecc.options	= NAND_ECC_GENERIC_ERASED_CHECK;

	chip->legacy.chip_delay = 50;

	chip->legacy.cmd_ctrl = jz_nand_cmd_ctrl;

	chip->legacy.select_chip = jz_nand_select_chip;

	chip->legacy.dummy_controller.ops = &jz_nand_controller_ops;

	if (nand->busy_gpio)

		chip->legacy.dev_ready = jz_nand_dev_ready;

	platform_set_drvdata(pdev, nand);

	/* We are going to autodetect NAND chips in the banks specified in the

	 * platform data. Although nand_scan_ident() can detect multiple chips,

	 * it requires those chips to be numbered consecuitively, which is not

	 * always the case for external memory banks. And a fixed chip-to-bank

	 * mapping is not practical either, since for example Dingoo units

	 * produced at different times have NAND chips in different banks.

	 */

	chipnr = 0;

	for (bank_idx = 0; bank_idx < JZ_NAND_NUM_BANKS; bank_idx++) {

		unsigned char bank;

		/* If there is no platform data, look for NAND in bank 1,

		 * which is the most likely bank since it is the only one

		 * that can be booted from.

		 */

		bank = pdata ? pdata->banks[bank_idx] : bank_idx ^ 1;

		if (bank == 0)

			break;

		if (bank > JZ_NAND_NUM_BANKS) {

			dev_warn(&pdev->dev,

				"Skipping non-existing bank: %d\n", bank);

			continue;

		}

		/* The detection routine will directly or indirectly call

		 * jz_nand_select_chip(), so nand->banks has to contain the

		 * bank we're checking.

		 */

		nand->banks[chipnr] = bank;

		if (jz_nand_detect_bank(pdev, nand, bank, chipnr,

					&nand_maf_id, &nand_dev_id) == 0)

			chipnr++;

		else

			nand->banks[chipnr] = 0;

	}

	if (chipnr == 0) {

		dev_err(&pdev->dev, "No NAND chips found\n");

		goto err_iounmap_mmio;

	}

	ret = mtd_device_register(mtd, pdata ? pdata->partitions : NULL,

				  pdata ? pdata->num_partitions : 0);

	if (ret) {

		dev_err(&pdev->dev, "Failed to add mtd device\n");

		goto err_cleanup_nand;

	}

	dev_info(&pdev->dev, "Successfully registered JZ4740 NAND driver\n");

	return 0;

err_cleanup_nand:

	nand_cleanup(chip);

	while (chipnr--) {

		unsigned char bank = nand->banks[chipnr];

		jz_nand_iounmap_resource(nand->bank_mem[bank - 1],

					 nand->bank_base[bank - 1]);

	}

	writel(0, nand->base + JZ_REG_NAND_CTRL);

err_iounmap_mmio:

	jz_nand_iounmap_resource(nand->mem, nand->base);

err_free:

	kfree(nand);

	return ret;

}

static int jz_nand_remove(struct platform_device *pdev)

{

	struct jz_nand *nand = platform_get_drvdata(pdev);

	size_t i;

	nand_release(&nand->chip);

	/* Deassert and disable all chips */

	writel(0, nand->base + JZ_REG_NAND_CTRL);

	for (i = 0; i < JZ_NAND_NUM_BANKS; ++i) {

		unsigned char bank = nand->banks[i];

		if (bank != 0) {

			jz_nand_iounmap_resource(nand->bank_mem[bank - 1],

						 nand->bank_base[bank - 1]);

		}

	}

	jz_nand_iounmap_resource(nand->mem, nand->base);

	kfree(nand);

	return 0;

}

static struct platform_driver jz_nand_driver = {

	.probe = jz_nand_probe,

	.remove = jz_nand_remove,

	.driver = {

		.name = "jz4740-nand",

	},

};

module_platform_driver(jz_nand_driver);

MODULE_LICENSE("GPL");

MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");

MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");

MODULE_ALIAS("platform:jz4740-nand");