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From: Lars-Peter Clausen on 17 Jul 2010 08:20
This patch adds support for the NAND controller on JZ4740 SoCs.

Signed-off-by: Lars-Peter Clausen <lars(a)metafoo.de>
Cc: David Woodhouse <dwmw2(a)infradead.org>
Cc: linux-mtd(a)lists.infradead.org

--
Changes since v1
- JZ4740: Remove debug macro
- Fix platform driver remove callback
- Add custom nand read/write callback since we need to support more then 64 ecc
bytes

Changes since v2
- Fix potential deadlock that can happen when the hardware is broken
- Move include file from include/linux/mtd/ to arch/mips/include/asm/mach-jz4740/
- {Enable,Disable} NAND-chip in {probe,remove}
- Supply memory bank address through platform resource
---
arch/mips/include/asm/mach-jz4740/jz4740_nand.h | 34 ++
drivers/mtd/nand/Kconfig | 6 +
drivers/mtd/nand/Makefile | 1 +
drivers/mtd/nand/jz4740_nand.c | 516 +++++++++++++++++++++++
4 files changed, 557 insertions(+), 0 deletions(-)
create mode 100644 arch/mips/include/asm/mach-jz4740/jz4740_nand.h
create mode 100644 drivers/mtd/nand/jz4740_nand.c

diff --git a/arch/mips/include/asm/mach-jz4740/jz4740_nand.h b/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
new file mode 100644
index 0000000..bb5b9a4
--- /dev/null
+++ b/arch/mips/include/asm/mach-jz4740/jz4740_nand.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2009-2010, Lars-Peter Clausen <lars(a)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.
+ *
+ */
+
+#ifndef __ASM_MACH_JZ4740_JZ4740_NAND_H__
+#define __ASM_MACH_JZ4740_JZ4740_NAND_H__
+
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+
+struct jz_nand_platform_data {
+ int num_partitions;
+ struct mtd_partition *partitions;
+
+ struct nand_ecclayout *ecc_layout;
+
+ unsigned int busy_gpio;
+
+ void (*ident_callback)(struct platform_device *, struct nand_chip *,
+ struct mtd_partition **, int *num_partitions);
+};
+
+#endif
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index ffc3720..362d177 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -526,4 +526,10 @@ config MTD_NAND_NUC900
This enables the driver for the NAND Flash on evaluation board based
on w90p910 / NUC9xx.

+config MTD_NAND_JZ4740
+ tristate "Support for JZ4740 SoC NAND controller"
+ depends on MACH_JZ4740
+ help
+ Enables support for NAND Flash on JZ4740 SoC based boards.
+
endif # MTD_NAND
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index e8ab884..ac83dcd 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -46,5 +46,6 @@ obj-$(CONFIG_MTD_NAND_NOMADIK) += nomadik_nand.o
obj-$(CONFIG_MTD_NAND_BCM_UMI) += bcm_umi_nand.o nand_bcm_umi.o
obj-$(CONFIG_MTD_NAND_MPC5121_NFC) += mpc5121_nfc.o
obj-$(CONFIG_MTD_NAND_RICOH) += r852.o
+obj-$(CONFIG_MTD_NAND_JZ4740) += jz4740_nand.o

nand-objs := nand_base.o nand_bbt.o
diff --git a/drivers/mtd/nand/jz4740_nand.c b/drivers/mtd/nand/jz4740_nand.c
new file mode 100644
index 0000000..67343fc
--- /dev/null
+++ b/drivers/mtd/nand/jz4740_nand.c
@@ -0,0 +1,516 @@
+/*
+ * Copyright (C) 2009-2010, Lars-Peter Clausen <lars(a)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_MEM_ADDR_OFFSET 0x10000
+#define JZ_NAND_MEM_CMD_OFFSET 0x08000
+
+struct jz_nand {
+ struct mtd_info mtd;
+ struct nand_chip chip;
+ void __iomem *base;
+ struct resource *mem;
+
+ void __iomem *bank_base;
+ struct resource *bank_mem;
+
+ struct jz_nand_platform_data *pdata;
+ 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_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;
+
+ if (ctrl & NAND_CTRL_CHANGE) {
+ BUG_ON((ctrl & NAND_ALE) && (ctrl & NAND_CLE));
+ if (ctrl & NAND_ALE)
+ chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_ADDR_OFFSET;
+ else if (ctrl & NAND_CLE)
+ chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_CMD_OFFSET;
+ else
+ chip->IO_ADDR_W = nand->bank_base;
+
+ reg = readl(nand->base + JZ_REG_NAND_CTRL);
+ if (ctrl & NAND_NCE)
+ reg |= JZ_NAND_CTRL_ASSERT_CHIP(0);
+ else
+ reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(0);
+ 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 gpio_get_value_cansleep(nand->pdata->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;
+}
+
+
+/* Copy paste of nand_read_page_hwecc_oob_first except for different eccpos
+ * handling. The ecc area is for 4k chips 72 bytes long and thus does not fit
+ * into the eccpos array. */
+static int jz_nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
+ struct nand_chip *chip, uint8_t *buf, int page)
+{
+ int i, eccsize = chip->ecc.size;
+ int eccbytes = chip->ecc.bytes;
+ int eccsteps = chip->ecc.steps;
+ uint8_t *p = buf;
+ unsigned int ecc_offset = chip->page_shift;
+
+ /* Read the OOB area first */
+ chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
+ chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+ chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
+
+ for (i = ecc_offset; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
+ int stat;
+
+ chip->ecc.hwctl(mtd, NAND_ECC_READ);
+ chip->read_buf(mtd, p, eccsize);
+
+ stat = chip->ecc.correct(mtd, p, &chip->oob_poi[i], NULL);
+ if (stat < 0)
+ mtd->ecc_stats.failed++;
+ else
+ mtd->ecc_stats.corrected += stat;
+ }
+ return 0;
+}
+
+/* Copy-and-paste of nand_write_page_hwecc with different eccpos handling. */
+static void jz_nand_write_page_hwecc(struct mtd_info *mtd,
+ struct nand_chip *chip, const uint8_t *buf)
+{
+ int i, eccsize = chip->ecc.size;
+ int eccbytes = chip->ecc.bytes;
+ int eccsteps = chip->ecc.steps;
+ const uint8_t *p = buf;
+ unsigned int ecc_offset = chip->page_shift;
+
+ for (i = ecc_offset; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
+ chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
+ chip->write_buf(mtd, p, eccsize);
+ chip->ecc.calculate(mtd, p, &chip->oob_poi[i]);
+ }
+
+ chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+}
+
+#ifdef CONFIG_MTD_CMDLINE_PARTS
+static const char *part_probes[] = {"cmdline", NULL};
+#endif
+
+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 int __devinit 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 = pdev->dev.platform_data;
+#ifdef CONFIG_MTD_PARTITIONS
+ struct mtd_partition *partition_info;
+ int num_partitions = 0;
+#endif
+
+ nand = kzalloc(sizeof(*nand), GFP_KERNEL);
+ if (!nand) {
+ dev_err(&pdev->dev, "Failed to allocate device structure.\n");
+ return -ENOMEM;
+ }
+
+ ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);
+ if (ret)
+ goto err_free;
+ ret = jz_nand_ioremap_resource(pdev, "bank", &nand->bank_mem,
+ &nand->bank_base);
+ if (ret)
+ goto err_iounmap_mmio;
+
+ if (pdata && gpio_is_valid(pdata->busy_gpio)) {
+ ret = gpio_request(pdata->busy_gpio, "NAND busy pin");
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Failed to request busy gpio %d: %d\n",
+ pdata->busy_gpio, ret);
+ goto err_iounmap_mem;
+ }
+ }
+
+ 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.read_page = jz_nand_read_page_hwecc_oob_first;
+ chip->ecc.write_page = jz_nand_write_page_hwecc;
+
+ if (pdata)
+ chip->ecc.layout = pdata->ecc_layout;
+
+ chip->chip_delay = 50;
+ chip->cmd_ctrl = jz_nand_cmd_ctrl;
+
+ if (pdata && gpio_is_valid(pdata->busy_gpio))
+ chip->dev_ready = jz_nand_dev_ready;
+
+ chip->IO_ADDR_R = nand->bank_base;
+ chip->IO_ADDR_W = nand->bank_base;
+
+ nand->pdata = pdata;
+ platform_set_drvdata(pdev, nand);
+
+ writel(JZ_NAND_CTRL_ENABLE_CHIP(0), nand->base + JZ_REG_NAND_CTRL);
+
+ ret = nand_scan_ident(mtd, 1, NULL);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to scan nand\n");
+ goto err_gpio_free;
+ }
+
+ 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_gpio_free;
+ }
+
+#ifdef CONFIG_MTD_PARTITIONS
+#ifdef CONFIG_MTD_CMDLINE_PARTS
+ num_partitions = parse_mtd_partitions(mtd, part_probes,
+ &partition_info, 0);
+#endif
+ if (num_partitions <= 0 && pdata) {
+ num_partitions = pdata->num_partitions;
+ partition_info = pdata->partitions;
+ }
+
+ if (num_partitions > 0)
+ ret = add_mtd_partitions(mtd, partition_info, num_partitions);
+ else
+#endif
+ ret = add_mtd_device(mtd);
+
+ 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(&nand->mtd);
+err_gpio_free:
+ platform_set_drvdata(pdev, NULL);
+ gpio_free(pdata->busy_gpio);
+err_iounmap_mem:
+ iounmap(nand->bank_base);
+err_iounmap_mmio:
+ iounmap(nand->base);
+err_free:
+ kfree(nand);
+ return ret;
+}
+
+static int __devexit jz_nand_remove(struct platform_device *pdev)
+{
+ struct jz_nand *nand = platform_get_drvdata(pdev);
+
+ nand_release(&nand->mtd);
+
+ /* Deassert and disable all chips */
+ writel(0, nand->base + JZ_REG_NAND_CTRL);
+
+ iounmap(nand->bank_base);
+ release_mem_region(nand->bank_mem->start, resource_size(nand->bank_mem));
+ iounmap(nand->base);
+ release_mem_region(nand->mem->start, resource_size(nand->mem));
+
+ platform_set_drvdata(pdev, NULL);
+ kfree(nand);
+
+ return 0;
+}
+
+struct platform_driver jz_nand_driver = {
+ .probe = jz_nand_probe,
+ .remove = __devexit_p(jz_nand_remove),
+ .driver = {
+ .name = "jz4740-nand",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init jz_nand_init(void)
+{
+ return platform_driver_register(&jz_nand_driver);
+}
+module_init(jz_nand_init);
+
+static void __exit jz_nand_exit(void)
+{
+ platform_driver_unregister(&jz_nand_driver);
+}
+module_exit(jz_nand_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Lars-Peter Clausen <lars(a)metafoo.de>");
+MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");
+MODULE_ALIAS("platform:jz4740-nand");
--
1.5.6.5

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