diff options
Diffstat (limited to 'drivers/mtd/nand/nand_s3c24xx.c')
-rw-r--r-- | drivers/mtd/nand/nand_s3c24xx.c | 665 |
1 files changed, 665 insertions, 0 deletions
diff --git a/drivers/mtd/nand/nand_s3c24xx.c b/drivers/mtd/nand/nand_s3c24xx.c new file mode 100644 index 0000000000..c4fd13ebfd --- /dev/null +++ b/drivers/mtd/nand/nand_s3c24xx.c @@ -0,0 +1,665 @@ +/* linux/drivers/mtd/nand/s3c2410.c + * + * Copyright (C) 2009 Juergen Beisert, Pengutronix + * + * Copyright © 2004-2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * Samsung S3C2410 NAND 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +#include <config.h> +#include <common.h> +#include <driver.h> +#include <malloc.h> +#include <init.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/nand.h> +#include <mach/s3c-generic.h> +#include <mach/s3c-iomap.h> +#include <mach/s3c24xx-nand.h> +#include <io.h> +#include <asm-generic/errno.h> + +#ifdef CONFIG_S3C24XX_NAND_BOOT +# define __nand_boot_init __bare_init +# ifndef BOARD_DEFAULT_NAND_TIMING +# define BOARD_DEFAULT_NAND_TIMING 0x0737 +# endif +#else +# define __nand_boot_init +#endif + +/** + * Define this symbol for testing purpose. It will add a command to read an + * image from the NAND like it the boot strap code will do. + */ +#define CONFIG_NAND_S3C24XX_BOOT_DEBUG + +/* NAND controller's register */ + +#define NFCONF 0x00 + +#ifdef CONFIG_CPU_S3C2410 + +#define NFCMD 0x04 +#define NFADDR 0x08 +#define NFDATA 0x0c +#define NFSTAT 0x10 +#define NFECC 0x14 + +/* S3C2410 specific bits */ +#define NFSTAT_BUSY (1) +#define NFCONF_nFCE (1 << 11) +#define NFCONF_INITECC (1 << 12) +#define NFCONF_EN (1 << 15) + +#endif /* CONFIG_CPU_S3C2410 */ + +#ifdef CONFIG_CPU_S3C2440 + +#define NFCONT 0x04 +#define NFCMD 0x08 +#define NFADDR 0x0C +#define NFDATA 0x10 +#define NFSTAT 0x20 +#define NFECC 0x2C + +/* S3C2440 specific bits */ +#define NFSTAT_BUSY (1) +#define NFCONT_nFCE (1 << 1) +#define NFCONT_INITECC (1 << 4) +#define NFCONT_EN (1) + +#endif /* CONFIG_CPU_S3C2440 */ + + +struct s3c24x0_nand_host { + struct mtd_info mtd; + struct nand_chip nand; + struct mtd_partition *parts; + struct device_d *dev; + + void __iomem *base; +}; + +/** + * oob placement block for use with hardware ecc generation on small page + */ +static struct nand_ecclayout nand_hw_eccoob = { + .eccbytes = 3, + .eccpos = { 0, 1, 2}, + .oobfree = { + { + .offset = 8, + .length = 8 + } + } +}; + +/* - Functions shared between the boot strap code and the regular driver - */ + +/** + * Issue the specified command to the NAND device + * @param[in] host Base address of the NAND controller + * @param[in] cmd Command for NAND flash + */ +static void __nand_boot_init send_cmd(void __iomem *host, uint8_t cmd) +{ + writeb(cmd, host + NFCMD); +} + +/** + * Issue the specified address to the NAND device + * @param[in] host Base address of the NAND controller + * @param[in] addr Address for the NAND flash + */ +static void __nand_boot_init send_addr(void __iomem *host, uint8_t addr) +{ + writeb(addr, host + NFADDR); +} + +/** + * Enable the NAND flash access + * @param[in] host Base address of the NAND controller + */ +static void __nand_boot_init enable_cs(void __iomem *host) +{ +#ifdef CONFIG_CPU_S3C2410 + writew(readw(host + NFCONF) & ~NFCONF_nFCE, host + NFCONF); +#endif +#ifdef CONFIG_CPU_S3C2440 + writew(readw(host + NFCONT) & ~NFCONT_nFCE, host + NFCONT); +#endif +} + +/** + * Disable the NAND flash access + * @param[in] host Base address of the NAND controller + */ +static void __nand_boot_init disable_cs(void __iomem *host) +{ +#ifdef CONFIG_CPU_S3C2410 + writew(readw(host + NFCONF) | NFCONF_nFCE, host + NFCONF); +#endif +#ifdef CONFIG_CPU_S3C2440 + writew(readw(host + NFCONT) | NFCONT_nFCE, host + NFCONT); +#endif +} + +/** + * Enable the NAND flash controller + * @param[in] host Base address of the NAND controller + * @param[in] timing Timing to access the NAND memory + */ +static void __nand_boot_init enable_nand_controller(void __iomem *host, uint32_t timing) +{ +#ifdef CONFIG_CPU_S3C2410 + writew(timing + NFCONF_EN + NFCONF_nFCE, host + NFCONF); +#endif +#ifdef CONFIG_CPU_S3C2440 + writew(NFCONT_EN + NFCONT_nFCE, host + NFCONT); + writew(timing, host + NFCONF); +#endif +} + +/** + * Diable the NAND flash controller + * @param[in] host Base address of the NAND controller + */ +static void __nand_boot_init disable_nand_controller(void __iomem *host) +{ +#ifdef CONFIG_CPU_S3C2410 + writew(NFCONF_nFCE, host + NFCONF); +#endif +#ifdef CONFIG_CPU_S3C2440 + writew(NFCONT_nFCE, host + NFCONT); +#endif +} + +/* ----------------------------------------------------------------------- */ + +#ifdef CONFIG_CPU_S3C2440 +/** + * Read one block of data from the NAND port + * @param[in] mtd Instance data + * @param[out] buf buffer to write data to + * @param[in] len byte count + * + * This is a special block read variant for the S3C2440 CPU. + */ +static void s3c2440_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len) +{ + struct nand_chip *nand_chip = mtd->priv; + struct s3c24x0_nand_host *host = nand_chip->priv; + + readsl(host->base + NFDATA, buf, len >> 2); + + /* cleanup any fractional read */ + if (len & 3) { + buf += len & ~3; + + for (; len & 3; len--) + *buf++ = readb(host->base + NFDATA); + } +} + +/** + * Write one block of data to the NAND port + * @param[in] mtd Instance data + * @param[out] buf buffer to read data from + * @param[in] len byte count + * + * This is a special block write variant for the S3C2440 CPU. + */ +static void s3c2440_nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, + int len) +{ + struct nand_chip *nand_chip = mtd->priv; + struct s3c24x0_nand_host *host = nand_chip->priv; + + writesl(host->base + NFDATA, buf, len >> 2); + + /* cleanup any fractional write */ + if (len & 3) { + buf += len & ~3; + + for (; len & 3; len--, buf++) + writeb(*buf, host->base + NFDATA); + } +} +#endif + +/** + * Check the ECC and try to repair the data if possible + * @param[in] mtd_info Not used + * @param[inout] dat Pointer to the data buffer that might contain a bit error + * @param[in] read_ecc ECC data from the OOB space + * @param[in] calc_ecc ECC data calculated from the data + * @return 0 no error, 1 repaired error, -1 no way... + * + * @note: This routine works always on a 24 bit ECC + */ +static int s3c2410_nand_correct_data(struct mtd_info *mtd, uint8_t *dat, + uint8_t *read_ecc, uint8_t *calc_ecc) +{ + unsigned int diff0, diff1, diff2; + unsigned int bit, byte; + + diff0 = read_ecc[0] ^ calc_ecc[0]; + diff1 = read_ecc[1] ^ calc_ecc[1]; + diff2 = read_ecc[2] ^ calc_ecc[2]; + + if (diff0 == 0 && diff1 == 0 && diff2 == 0) + return 0; /* ECC is ok */ + + /* sometimes people do not think about using the ECC, so check + * to see if we have an 0xff,0xff,0xff read ECC and then ignore + * the error, on the assumption that this is an un-eccd page. + */ + if (read_ecc[0] == 0xff && read_ecc[1] == 0xff && read_ecc[2] == 0xff) + return 0; + + /* Can we correct this ECC (ie, one row and column change). + * Note, this is similar to the 256 error code on smartmedia */ + + if (((diff0 ^ (diff0 >> 1)) & 0x55) == 0x55 && + ((diff1 ^ (diff1 >> 1)) & 0x55) == 0x55 && + ((diff2 ^ (diff2 >> 1)) & 0x55) == 0x55) { + /* calculate the bit position of the error */ + + bit = ((diff2 >> 3) & 1) | + ((diff2 >> 4) & 2) | + ((diff2 >> 5) & 4); + + /* calculate the byte position of the error */ + + byte = ((diff2 << 7) & 0x100) | + ((diff1 << 0) & 0x80) | + ((diff1 << 1) & 0x40) | + ((diff1 << 2) & 0x20) | + ((diff1 << 3) & 0x10) | + ((diff0 >> 4) & 0x08) | + ((diff0 >> 3) & 0x04) | + ((diff0 >> 2) & 0x02) | + ((diff0 >> 1) & 0x01); + + dat[byte] ^= (1 << bit); + return 1; + } + + /* if there is only one bit difference in the ECC, then + * one of only a row or column parity has changed, which + * means the error is most probably in the ECC itself */ + + diff0 |= (diff1 << 8); + diff0 |= (diff2 << 16); + + if ((diff0 & ~(1<<fls(diff0))) == 0) + return 1; + + return -1; +} + +static void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode) +{ + struct nand_chip *nand_chip = mtd->priv; + struct s3c24x0_nand_host *host = nand_chip->priv; + +#ifdef CONFIG_CPU_S3C2410 + writel(readl(host->base + NFCONF) | NFCONF_INITECC , host->base + NFCONF); +#endif +#ifdef CONFIG_CPU_S3C2440 + writel(readl(host->base + NFCONT) | NFCONT_INITECC , host->base + NFCONT); +#endif +} + +static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat, uint8_t *ecc_code) +{ + struct nand_chip *nand_chip = mtd->priv; + struct s3c24x0_nand_host *host = nand_chip->priv; + +#ifdef CONFIG_CPU_S3C2410 + ecc_code[0] = readb(host->base + NFECC); + ecc_code[1] = readb(host->base + NFECC + 1); + ecc_code[2] = readb(host->base + NFECC + 2); +#endif +#ifdef CONFIG_CPU_S3C2440 + unsigned long ecc = readl(host->base + NFECC); + + ecc_code[0] = ecc; + ecc_code[1] = ecc >> 8; + ecc_code[2] = ecc >> 16; +#endif + return 0; +} + +static void s3c24x0_nand_select_chip(struct mtd_info *mtd, int chip) +{ + struct nand_chip *nand_chip = mtd->priv; + struct s3c24x0_nand_host *host = nand_chip->priv; + + if (chip == -1) + disable_cs(host->base); + else + enable_cs(host->base); +} + +static int s3c24x0_nand_devready(struct mtd_info *mtd) +{ + struct nand_chip *nand_chip = mtd->priv; + struct s3c24x0_nand_host *host = nand_chip->priv; + + return readw(host->base + NFSTAT) & NFSTAT_BUSY; +} + +static void s3c24x0_nand_hwcontrol(struct mtd_info *mtd, int cmd, + unsigned int ctrl) +{ + struct nand_chip *nand_chip = mtd->priv; + struct s3c24x0_nand_host *host = nand_chip->priv; + + if (cmd == NAND_CMD_NONE) + return; + /* + * If the CLE should be active, this call is a NAND command + */ + if (ctrl & NAND_CLE) + send_cmd(host->base, cmd); + /* + * If the ALE should be active, this call is a NAND address + */ + if (ctrl & NAND_ALE) + send_addr(host->base, cmd); +} + +static int s3c24x0_nand_inithw(struct s3c24x0_nand_host *host) +{ + struct s3c24x0_nand_platform_data *pdata = host->dev->platform_data; + uint32_t tmp; + + /* reset the NAND controller */ + disable_nand_controller(host->base); + + if (pdata != NULL) + tmp = pdata->nand_timing; + else + /* else slowest possible timing */ + tmp = CALC_NFCONF_TIMING(4, 8, 8); + + /* reenable the NAND controller */ + enable_nand_controller(host->base, tmp); + + return 0; +} + +static int s3c24x0_nand_probe(struct device_d *dev) +{ + struct nand_chip *chip; + struct s3c24x0_nand_platform_data *pdata = dev->platform_data; + struct mtd_info *mtd; + struct s3c24x0_nand_host *host; + int ret; + + /* Allocate memory for MTD device structure and private data */ + host = kzalloc(sizeof(struct s3c24x0_nand_host), GFP_KERNEL); + if (!host) + return -ENOMEM; + + host->dev = dev; + host->base = dev_request_mem_region(dev, 0); + + /* structures must be linked */ + chip = &host->nand; + mtd = &host->mtd; + mtd->priv = chip; + + /* init the default settings */ + + /* 50 us command delay time */ + chip->chip_delay = 50; + chip->priv = host; + + chip->IO_ADDR_R = chip->IO_ADDR_W = host->base + NFDATA; + +#ifdef CONFIG_CPU_S3C2440 + chip->read_buf = s3c2440_nand_read_buf; + chip->write_buf = s3c2440_nand_write_buf; +#endif + chip->cmd_ctrl = s3c24x0_nand_hwcontrol; + chip->dev_ready = s3c24x0_nand_devready; + chip->select_chip = s3c24x0_nand_select_chip; + + /* we are using the hardware ECC feature of this device */ + chip->ecc.calculate = s3c2410_nand_calculate_ecc; + chip->ecc.correct = s3c2410_nand_correct_data; + chip->ecc.hwctl = s3c2410_nand_enable_hwecc; + + /* + * Setup ECC handling in accordance to the kernel + * - 1 times 512 bytes with 24 bit ECC for small page + * - 8 times 256 bytes with 24 bit ECC each for large page + */ + chip->ecc.mode = NAND_ECC_HW; + chip->ecc.bytes = 3; /* always 24 bit ECC per turn */ +#ifdef CONFIG_CPU_S3C2440 + if (readl(host->base) & 0x8) { + /* large page (2048 bytes per page) */ + chip->ecc.size = 256; + } else +#endif + { + /* small page (512 bytes per page) */ + chip->ecc.size = 512; + chip->ecc.layout = &nand_hw_eccoob; + } + + if (pdata->flash_bbt) { + /* use a flash based bbt */ + chip->options |= NAND_USE_FLASH_BBT; + } + + ret = s3c24x0_nand_inithw(host); + if (ret != 0) + goto on_error; + + /* Scan to find existence of the device */ + ret = nand_scan(mtd, 1); + if (ret != 0) { + ret = -ENXIO; + goto on_error; + } + + return add_mtd_device(mtd); + +on_error: + free(host); + return ret; +} + +static struct driver_d s3c24x0_nand_driver = { + .name = "s3c24x0_nand", + .probe = s3c24x0_nand_probe, +}; + +#ifdef CONFIG_S3C24XX_NAND_BOOT + +static void __nand_boot_init wait_for_completion(void __iomem *host) +{ + while (!(readw(host + NFSTAT) & NFSTAT_BUSY)) + ; +} + +/** + * Convert a page offset into a page address for the NAND + * @param host Where to write the address to + * @param offs Page's offset in the NAND + * @param ps Page size (512 or 2048) + * @param c Address cycle count (3, 4 or 5) + * + * Uses the offset of the page to generate an page address into the NAND. This + * differs when using a 512 byte or 2048 bytes per page NAND. + * The collumn part of the page address to be generated is always forced to '0'. + */ +static void __nand_boot_init nfc_addr(void __iomem *host, uint32_t offs, + int ps, int c) +{ + send_addr(host, 0); /* collumn part 1 */ + + if (ps == 512) { + send_addr(host, offs >> 9); + send_addr(host, offs >> 17); + if (c > 3) + send_addr(host, offs >> 25); + } else { + send_addr(host, 0); /* collumn part 2 */ + send_addr(host, offs >> 11); + send_addr(host, offs >> 19); + if (c > 4) + send_addr(host, offs >> 27); + send_cmd(host, NAND_CMD_READSTART); + } +} + +/** + * Load a sequential count of pages from the NAND into memory + * @param[out] dest Pointer to target area (in SDRAM) + * @param[in] size Bytes to read from NAND device + * @param[in] page Start page to read from + * + * This function must be located in the first 4kiB of the barebox image + * (guess why). + */ +void __nand_boot_init s3c24x0_nand_load_image(void *dest, int size, int page) +{ + void __iomem *host = (void __iomem *)S3C24X0_NAND_BASE; + unsigned pagesize; + int i, cycle; + + /* + * Reenable the NFC and use the default (but slow) access + * timing or the board specific setting if provided. + */ + enable_nand_controller(host, BOARD_DEFAULT_NAND_TIMING); + + /* use the current NAND hardware configuration */ + switch (readl(S3C24X0_NAND_BASE) & 0xf) { + case 0x6: /* 8 bit, 4 addr cycles, 512 bpp, normal NAND */ + pagesize = 512; + cycle = 4; + break; + case 0xc: /* 8 bit, 4 addr cycles, 2048 bpp, advanced NAND */ + pagesize = 2048; + cycle = 4; + break; + case 0xe: /* 8 bit, 5 addr cycles, 2048 bpp, advanced NAND */ + pagesize = 2048; + cycle = 5; + break; + default: + /* we cannot output an error message here :-( */ + disable_nand_controller(host); + return; + } + + enable_cs(host); + + /* Reset the NAND device */ + send_cmd(host, NAND_CMD_RESET); + wait_for_completion(host); + disable_cs(host); + + do { + enable_cs(host); + send_cmd(host, NAND_CMD_READ0); + nfc_addr(host, page * pagesize, pagesize, cycle); + wait_for_completion(host); + /* copy one page (do *not* use readsb() here!)*/ + for (i = 0; i < pagesize; i++) + writeb(readb(host + NFDATA), (void __iomem *)(dest + i)); + disable_cs(host); + + page++; + dest += pagesize; + size -= pagesize; + } while (size >= 0); + + /* disable the controller again */ + disable_nand_controller(host); +} + +#ifdef CONFIG_NAND_S3C24XX_BOOT_DEBUG +#include <command.h> + +static int do_nand_boot_test(struct command *cmdtp, int argc, char *argv[]) +{ + void *dest; + int size; + + if (argc < 3) + return COMMAND_ERROR_USAGE; + + dest = (void *)strtoul_suffix(argv[1], NULL, 0); + size = strtoul_suffix(argv[2], NULL, 0); + + s3c24x0_nand_load_image(dest, size, 0); + + /* re-enable the controller again, as this was a test only */ + enable_nand_controller((void *)S3C24X0_NAND_BASE, + BOARD_DEFAULT_NAND_TIMING); + + return 0; +} + +static const __maybe_unused char cmd_nand_boot_test_help[] = +"Usage: nand_boot_test <dest> <size>\n"; + +BAREBOX_CMD_START(nand_boot_test) + .cmd = do_nand_boot_test, + .usage = "load an image from NAND", + BAREBOX_CMD_HELP(cmd_nand_boot_test_help) +BAREBOX_CMD_END +#endif + +#endif /* CONFIG_S3C24XX_NAND_BOOT */ + +/* + * Main initialization routine + * @return 0 if successful; non-zero otherwise + */ +static int __init s3c24x0_nand_init(void) +{ + return register_driver(&s3c24x0_nand_driver); +} + +device_initcall(s3c24x0_nand_init); + +/** + * @file + * @brief Support for various kinds of NAND devices + * + * ECC handling in this driver (in accordance to the current 2.6.38 kernel): + * - for small page NANDs it generates 3 ECC bytes out of 512 data bytes + * - for large page NANDs it generates 24 ECC bytes out of 2048 data bytes + * + * As small page NANDs are using 48 bits ECC per default, this driver uses a + * local OOB layout description, to shrink it down to 24 bits. This is a bad + * idea, but we cannot change it here, as the kernel is using this layout. + * + * For large page NANDs this driver uses the default layout, as the kernel does. + */ |