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Release 4.7 drivers/mtd/nand/jz4740_nand.c

Directory: drivers/mtd/nand
/*
 *  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/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 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); }

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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; }

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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); }

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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); }

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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); }

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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; }

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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; }

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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; }

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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; }

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static inline void jz_nand_iounmap_resource(struct resource *res, void __iomem *base) { iounmap(base); release_mem_region(res->start, resource_size(res)); }

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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 nand_chip *chip = &nand->chip; struct mtd_info *mtd = nand_to_mtd(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; }

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Total477100.00%3100.00%


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; 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, mtd, &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; }

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dmitry eremin-baryshkovdmitry eremin-baryshkov132.08%215.38%
mike dunnmike dunn81.28%215.38%
frans klaverfrans klaver71.12%17.69%
jingoo hanjingoo han40.64%17.69%
artem bityutskiyartem bityutskiy10.16%17.69%
Total625100.00%13100.00%


static int jz_nand_remove(struct platform_device *pdev) { struct jz_nand *nand = platform_get_drvdata(pdev); size_t i; nand_release(nand_to_mtd(&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]); gpio_free(JZ_GPIO_MEM_CS0 + bank - 1); } } jz_nand_iounmap_resource(nand->mem, nand->base); kfree(nand); return 0; }

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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");

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boris brezillonboris brezillon391.42%527.78%
dmitry eremin-baryshkovdmitry eremin-baryshkov130.47%211.11%
mike dunnmike dunn80.29%211.11%
frans klaverfrans klaver70.25%15.56%
jingoo hanjingoo han40.15%15.56%
brian norrisbrian norris30.11%15.56%
artem bityutskiyartem bityutskiy10.04%15.56%
axel linaxel lin10.04%15.56%
Total2755100.00%18100.00%
Directory: drivers/mtd/nand
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