diff options
Diffstat (limited to 'drivers/mtd/nand/raw/jz4740_nand.c')
| -rw-r--r-- | drivers/mtd/nand/raw/jz4740_nand.c | 543 |
1 files changed, 543 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/jz4740_nand.c b/drivers/mtd/nand/raw/jz4740_nand.c new file mode 100644 index 000000000..27603d78b --- /dev/null +++ b/drivers/mtd/nand/raw/jz4740_nand.c @@ -0,0 +1,543 @@ +/* + * 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/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 mtd_info *mtd, int chipnr) +{ + struct jz_nand *nand = mtd_to_jz_nand(mtd); + struct nand_chip *chip = mtd_to_nand(mtd); + 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_to_nand(mtd); + 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; + 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); + u8 id[2]; + + /* 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. */ + chip->select_chip(mtd, 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. */ + chip->select_chip(mtd, 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. */ + chip->numchips++; + mtd->size += chip->chipsize; + } + + 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->chip_delay = 50; + chip->cmd_ctrl = jz_nand_cmd_ctrl; + chip->select_chip = jz_nand_select_chip; + chip->dummy_controller.ops = &jz_nand_controller_ops; + + 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; + } + + 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"); |