MTD: Nand: Add JZ4740 NAND driver
authorLars-Peter Clausen <lars@metafoo.de>
Sat, 17 Jul 2010 11:15:29 +0000 (11:15 +0000)
committerRalf Baechle <ralf@linux-mips.org>
Thu, 5 Aug 2010 12:26:18 +0000 (13:26 +0100)
Add support for the NAND controller on JZ4740 SoCs.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1470/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/include/asm/mach-jz4740/jz4740_nand.h [new file with mode: 0644]
drivers/mtd/nand/Kconfig
drivers/mtd/nand/Makefile
drivers/mtd/nand/jz4740_nand.c [new file with mode: 0644]

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 (file)
index 0000000..bb5b9a4
--- /dev/null
@@ -0,0 +1,34 @@
+/*
+ *  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.
+ *
+ */
+
+#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
index ffc3720..362d177 100644 (file)
@@ -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
index e8ab884..ac83dcd 100644 (file)
@@ -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 (file)
index 0000000..67343fc
--- /dev/null
@@ -0,0 +1,516 @@
+/*
+ *  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_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@metafoo.de>");
+MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");
+MODULE_ALIAS("platform:jz4740-nand");