1 files changed, 579 insertions, 0 deletions

diff --git a/kernel/drivers/mtd/nand/jz4740_nand.c b/kernel/drivers/mtd/nand/jz4740_nand.c
new file mode 100644
index 000000000..ebf2cce04
--- /dev/null
+++ b/kernel/drivers/mtd/nand/jz4740_nand.c
@@ -0,0 +1,579 @@
+/*
+ *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
+ *  JZ4740 SoC NAND controller driver
+ *
+ *  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.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#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/nand.h>
+#include <linux/mtd/partitions.h>
+
+#include <linux/gpio.h>
+
+#include <asm/mach-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 mtd_info mtd;
+	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, struct jz_nand, mtd);
+}
+
+static void jz_nand_select_chip(struct mtd_info *mtd, int chipnr)
+{
+	struct jz_nand *nand = mtd_to_jz_nand(mtd);
+	struct nand_chip *chip = mtd->priv;
+	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->IO_ADDR_R = nand->bank_base[banknr];
+		chip->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 mtd_info *mtd, int dat, unsigned int ctrl)
+{
+	struct jz_nand *nand = mtd_to_jz_nand(mtd);
+	struct nand_chip *chip = mtd->priv;
+	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->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->IO_ADDR_W);
+}
+
+static int jz_nand_dev_ready(struct mtd_info *mtd)
+{
+	struct jz_nand *nand = mtd_to_jz_nand(mtd);
+	return gpiod_get_value_cansleep(nand->busy_gpio);
+}
+
+static void jz_nand_hwctl(struct mtd_info *mtd, int mode)
+{
+	struct jz_nand *nand = mtd_to_jz_nand(mtd);
+	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 mtd_info *mtd, const uint8_t *dat,
+	uint8_t *ecc_code)
+{
+	struct jz_nand *nand = mtd_to_jz_nand(mtd);
+	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 mtd_info *mtd, uint8_t *dat,
+	uint8_t *read_ecc, uint8_t *calc_ecc)
+{
+	struct jz_nand *nand = mtd_to_jz_nand(mtd);
+	int i, error_count, index;
+	uint32_t reg, status, error;
+	uint32_t t;
+	unsigned int timeout = 1000;
+
+	t = read_ecc[0];
+
+	if (t == 0xff) {
+		for (i = 1; i < 9; ++i)
+			t &= read_ecc[i];
+
+		t &= dat[0];
+		t &= dat[nand->chip.ecc.size / 2];
+		t &= dat[nand->chip.ecc.size - 1];
+
+		if (t == 0xff) {
+			for (i = 1; i < nand->chip.ecc.size - 1; ++i)
+				t &= dat[i];
+			if (t == 0xff)
+				return 0;
+		}
+	}
+
+	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 -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);
+
+	if (status & JZ_NAND_STATUS_ERROR) {
+		if (status & JZ_NAND_STATUS_UNCOR_ERROR)
+			return -1;
+
+		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;
+	int gpio;
+	char gpio_name[9];
+	char res_name[6];
+	uint32_t ctrl;
+	struct mtd_info *mtd = &nand->mtd;
+	struct nand_chip *chip = &nand->chip;
+
+	/* Request GPIO port. */
+	gpio = JZ_GPIO_MEM_CS0 + bank - 1;
+	sprintf(gpio_name, "NAND CS%d", bank);
+	ret = gpio_request(gpio, gpio_name);
+	if (ret) {
+		dev_warn(&pdev->dev,
+			"Failed to request %s gpio %d: %d\n",
+			gpio_name, gpio, ret);
+		goto notfound_gpio;
+	}
+
+	/* 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)
+		goto notfound_resource;
+
+	/* Enable chip in bank. */
+	jz_gpio_set_function(gpio, JZ_GPIO_FUNC_MEM_CS0);
+	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_ident(mtd, 1, NULL);
+		if (ret)
+			goto notfound_id;
+
+		/* Retrieve the IDs from the first chip. */
+		chip->select_chip(mtd, 0);
+		chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+		chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
+		*nand_maf_id = chip->read_byte(mtd);
+		*nand_dev_id = chip->read_byte(mtd);
+	} else {
+		/* Detect additional chip. */
+		chip->select_chip(mtd, chipnr);
+		chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+		chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
+		if (*nand_maf_id != chip->read_byte(mtd)
+		 || *nand_dev_id != chip->read_byte(mtd)) {
+			ret = -ENODEV;
+			goto notfound_id;
+		}
+
+		/* Update size of the MTD. */
+		chip->numchips++;
+		mtd->size += chip->chipsize;
+	}
+
+	dev_info(&pdev->dev, "Found chip %i 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_gpio_set_function(gpio, JZ_GPIO_FUNC_NONE);
+	jz_nand_iounmap_resource(nand->bank_mem[bank - 1],
+				 nand->bank_base[bank - 1]);
+notfound_resource:
+	gpio_free(gpio);
+notfound_gpio:
+	return ret;
+}
+
+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;
+	}
+
+	mtd		= &nand->mtd;
+	chip		= &nand->chip;
+	mtd->priv	= chip;
+	mtd->owner	= THIS_MODULE;
+	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;
+
+	if (pdata)
+		chip->ecc.layout = pdata->ecc_layout;
+
+	chip->chip_delay = 50;
+	chip->cmd_ctrl = jz_nand_cmd_ctrl;
+	chip->select_chip = jz_nand_select_chip;
+
+	if (nand->busy_gpio)
+		chip->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;
+	}
+
+	if (pdata && pdata->ident_callback) {
+		pdata->ident_callback(pdev, chip, &pdata->partitions,
+					&pdata->num_partitions);
+	}
+
+	ret = nand_scan_tail(mtd);
+	if (ret) {
+		dev_err(&pdev->dev,  "Failed to scan NAND\n");
+		goto err_unclaim_banks;
+	}
+
+	ret = mtd_device_parse_register(mtd, NULL, NULL,
+					pdata ? pdata->partitions : NULL,
+					pdata ? pdata->num_partitions : 0);
+
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to add mtd device\n");
+		goto err_nand_release;
+	}
+
+	dev_info(&pdev->dev, "Successfully registered JZ4740 NAND driver\n");
+
+	return 0;
+
+err_nand_release:
+	nand_release(mtd);
+err_unclaim_banks:
+	while (chipnr--) {
+		unsigned char bank = nand->banks[chipnr];
+		gpio_free(JZ_GPIO_MEM_CS0 + bank - 1);
+		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->mtd);
+
+	/* 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]);
+			gpio_free(JZ_GPIO_MEM_CS0 + 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");