diff options
Diffstat (limited to 'drivers/mtd/nand/davinci_nand.c')
| -rw-r--r-- | drivers/mtd/nand/davinci_nand.c | 570 |
1 files changed, 570 insertions, 0 deletions
diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c new file mode 100644 index 000000000000..0119220de7d0 --- /dev/null +++ b/drivers/mtd/nand/davinci_nand.c @@ -0,0 +1,570 @@ +/* + * davinci_nand.c - NAND Flash Driver for DaVinci family chips + * + * Copyright © 2006 Texas Instruments. + * + * Port to 2.6.23 Copyright © 2008 by: + * Sander Huijsen <Shuijsen@optelecom-nkf.com> + * Troy Kisky <troy.kisky@boundarydevices.com> + * Dirk Behme <Dirk.Behme@gmail.com> + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/mtd/nand.h> +#include <linux/mtd/partitions.h> + +#include <mach/nand.h> + +#include <asm/mach-types.h> + + +/* + * This is a device driver for the NAND flash controller found on the + * various DaVinci family chips. It handles up to four SoC chipselects, + * and some flavors of secondary chipselect (e.g. based on A12) as used + * with multichip packages. + * + * The 1-bit ECC hardware is supported, but not yet the newer 4-bit ECC + * available on chips like the DM355 and OMAP-L137 and needed with the + * more error-prone MLC NAND chips. + * + * This driver assumes EM_WAIT connects all the NAND devices' RDY/nBUSY + * outputs in a "wire-AND" configuration, with no per-chip signals. + */ +struct davinci_nand_info { + struct mtd_info mtd; + struct nand_chip chip; + + struct device *dev; + struct clk *clk; + bool partitioned; + + void __iomem *base; + void __iomem *vaddr; + + uint32_t ioaddr; + uint32_t current_cs; + + uint32_t mask_chipsel; + uint32_t mask_ale; + uint32_t mask_cle; + + uint32_t core_chipsel; +}; + +static DEFINE_SPINLOCK(davinci_nand_lock); + +#define to_davinci_nand(m) container_of(m, struct davinci_nand_info, mtd) + + +static inline unsigned int davinci_nand_readl(struct davinci_nand_info *info, + int offset) +{ + return __raw_readl(info->base + offset); +} + +static inline void davinci_nand_writel(struct davinci_nand_info *info, + int offset, unsigned long value) +{ + __raw_writel(value, info->base + offset); +} + +/*----------------------------------------------------------------------*/ + +/* + * Access to hardware control lines: ALE, CLE, secondary chipselect. + */ + +static void nand_davinci_hwcontrol(struct mtd_info *mtd, int cmd, + unsigned int ctrl) +{ + struct davinci_nand_info *info = to_davinci_nand(mtd); + uint32_t addr = info->current_cs; + struct nand_chip *nand = mtd->priv; + + /* Did the control lines change? */ + if (ctrl & NAND_CTRL_CHANGE) { + if ((ctrl & NAND_CTRL_CLE) == NAND_CTRL_CLE) + addr |= info->mask_cle; + else if ((ctrl & NAND_CTRL_ALE) == NAND_CTRL_ALE) + addr |= info->mask_ale; + + nand->IO_ADDR_W = (void __iomem __force *)addr; + } + + if (cmd != NAND_CMD_NONE) + iowrite8(cmd, nand->IO_ADDR_W); +} + +static void nand_davinci_select_chip(struct mtd_info *mtd, int chip) +{ + struct davinci_nand_info *info = to_davinci_nand(mtd); + uint32_t addr = info->ioaddr; + + /* maybe kick in a second chipselect */ + if (chip > 0) + addr |= info->mask_chipsel; + info->current_cs = addr; + + info->chip.IO_ADDR_W = (void __iomem __force *)addr; + info->chip.IO_ADDR_R = info->chip.IO_ADDR_W; +} + +/*----------------------------------------------------------------------*/ + +/* + * 1-bit hardware ECC ... context maintained for each core chipselect + */ + +static inline uint32_t nand_davinci_readecc_1bit(struct mtd_info *mtd) +{ + struct davinci_nand_info *info = to_davinci_nand(mtd); + + return davinci_nand_readl(info, NANDF1ECC_OFFSET + + 4 * info->core_chipsel); +} + +static void nand_davinci_hwctl_1bit(struct mtd_info *mtd, int mode) +{ + struct davinci_nand_info *info; + uint32_t nandcfr; + unsigned long flags; + + info = to_davinci_nand(mtd); + + /* Reset ECC hardware */ + nand_davinci_readecc_1bit(mtd); + + spin_lock_irqsave(&davinci_nand_lock, flags); + + /* Restart ECC hardware */ + nandcfr = davinci_nand_readl(info, NANDFCR_OFFSET); + nandcfr |= BIT(8 + info->core_chipsel); + davinci_nand_writel(info, NANDFCR_OFFSET, nandcfr); + + spin_unlock_irqrestore(&davinci_nand_lock, flags); +} + +/* + * Read hardware ECC value and pack into three bytes + */ +static int nand_davinci_calculate_1bit(struct mtd_info *mtd, + const u_char *dat, u_char *ecc_code) +{ + unsigned int ecc_val = nand_davinci_readecc_1bit(mtd); + unsigned int ecc24 = (ecc_val & 0x0fff) | ((ecc_val & 0x0fff0000) >> 4); + + /* invert so that erased block ecc is correct */ + ecc24 = ~ecc24; + ecc_code[0] = (u_char)(ecc24); + ecc_code[1] = (u_char)(ecc24 >> 8); + ecc_code[2] = (u_char)(ecc24 >> 16); + + return 0; +} + +static int nand_davinci_correct_1bit(struct mtd_info *mtd, u_char *dat, + u_char *read_ecc, u_char *calc_ecc) +{ + struct nand_chip *chip = mtd->priv; + uint32_t eccNand = read_ecc[0] | (read_ecc[1] << 8) | + (read_ecc[2] << 16); + uint32_t eccCalc = calc_ecc[0] | (calc_ecc[1] << 8) | + (calc_ecc[2] << 16); + uint32_t diff = eccCalc ^ eccNand; + + if (diff) { + if ((((diff >> 12) ^ diff) & 0xfff) == 0xfff) { + /* Correctable error */ + if ((diff >> (12 + 3)) < chip->ecc.size) { + dat[diff >> (12 + 3)] ^= BIT((diff >> 12) & 7); + return 1; + } else { + return -1; + } + } else if (!(diff & (diff - 1))) { + /* Single bit ECC error in the ECC itself, + * nothing to fix */ + return 1; + } else { + /* Uncorrectable error */ + return -1; + } + + } + return 0; +} + +/*----------------------------------------------------------------------*/ + +/* + * NOTE: NAND boot requires ALE == EM_A[1], CLE == EM_A[2], so that's + * how these chips are normally wired. This translates to both 8 and 16 + * bit busses using ALE == BIT(3) in byte addresses, and CLE == BIT(4). + * + * For now we assume that configuration, or any other one which ignores + * the two LSBs for NAND access ... so we can issue 32-bit reads/writes + * and have that transparently morphed into multiple NAND operations. + */ +static void nand_davinci_read_buf(struct mtd_info *mtd, uint8_t *buf, int len) +{ + struct nand_chip *chip = mtd->priv; + + if ((0x03 & ((unsigned)buf)) == 0 && (0x03 & len) == 0) + ioread32_rep(chip->IO_ADDR_R, buf, len >> 2); + else if ((0x01 & ((unsigned)buf)) == 0 && (0x01 & len) == 0) + ioread16_rep(chip->IO_ADDR_R, buf, len >> 1); + else + ioread8_rep(chip->IO_ADDR_R, buf, len); +} + +static void nand_davinci_write_buf(struct mtd_info *mtd, + const uint8_t *buf, int len) +{ + struct nand_chip *chip = mtd->priv; + + if ((0x03 & ((unsigned)buf)) == 0 && (0x03 & len) == 0) + iowrite32_rep(chip->IO_ADDR_R, buf, len >> 2); + else if ((0x01 & ((unsigned)buf)) == 0 && (0x01 & len) == 0) + iowrite16_rep(chip->IO_ADDR_R, buf, len >> 1); + else + iowrite8_rep(chip->IO_ADDR_R, buf, len); +} + +/* + * Check hardware register for wait status. Returns 1 if device is ready, + * 0 if it is still busy. + */ +static int nand_davinci_dev_ready(struct mtd_info *mtd) +{ + struct davinci_nand_info *info = to_davinci_nand(mtd); + + return davinci_nand_readl(info, NANDFSR_OFFSET) & BIT(0); +} + +static void __init nand_dm6446evm_flash_init(struct davinci_nand_info *info) +{ + uint32_t regval, a1cr; + + /* + * NAND FLASH timings @ PLL1 == 459 MHz + * - AEMIF.CLK freq = PLL1/6 = 459/6 = 76.5 MHz + * - AEMIF.CLK period = 1/76.5 MHz = 13.1 ns + */ + regval = 0 + | (0 << 31) /* selectStrobe */ + | (0 << 30) /* extWait (never with NAND) */ + | (1 << 26) /* writeSetup 10 ns */ + | (3 << 20) /* writeStrobe 40 ns */ + | (1 << 17) /* writeHold 10 ns */ + | (0 << 13) /* readSetup 10 ns */ + | (3 << 7) /* readStrobe 60 ns */ + | (0 << 4) /* readHold 10 ns */ + | (3 << 2) /* turnAround ?? ns */ + | (0 << 0) /* asyncSize 8-bit bus */ + ; + a1cr = davinci_nand_readl(info, A1CR_OFFSET); + if (a1cr != regval) { + dev_dbg(info->dev, "Warning: NAND config: Set A1CR " \ + "reg to 0x%08x, was 0x%08x, should be done by " \ + "bootloader.\n", regval, a1cr); + davinci_nand_writel(info, A1CR_OFFSET, regval); + } +} + +/*----------------------------------------------------------------------*/ + +static int __init nand_davinci_probe(struct platform_device *pdev) +{ + struct davinci_nand_pdata *pdata = pdev->dev.platform_data; + struct davinci_nand_info *info; + struct resource *res1; + struct resource *res2; + void __iomem *vaddr; + void __iomem *base; + int ret; + uint32_t val; + nand_ecc_modes_t ecc_mode; + + /* which external chipselect will we be managing? */ + if (pdev->id < 0 || pdev->id > 3) + return -ENODEV; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) { + dev_err(&pdev->dev, "unable to allocate memory\n"); + ret = -ENOMEM; + goto err_nomem; + } + + platform_set_drvdata(pdev, info); + + res1 = platform_get_resource(pdev, IORESOURCE_MEM, 0); + res2 = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!res1 || !res2) { + dev_err(&pdev->dev, "resource missing\n"); + ret = -EINVAL; + goto err_nomem; + } + + vaddr = ioremap(res1->start, res1->end - res1->start); + base = ioremap(res2->start, res2->end - res2->start); + if (!vaddr || !base) { + dev_err(&pdev->dev, "ioremap failed\n"); + ret = -EINVAL; + goto err_ioremap; + } + + info->dev = &pdev->dev; + info->base = base; + info->vaddr = vaddr; + + info->mtd.priv = &info->chip; + info->mtd.name = dev_name(&pdev->dev); + info->mtd.owner = THIS_MODULE; + + info->mtd.dev.parent = &pdev->dev; + + info->chip.IO_ADDR_R = vaddr; + info->chip.IO_ADDR_W = vaddr; + info->chip.chip_delay = 0; + info->chip.select_chip = nand_davinci_select_chip; + + /* options such as NAND_USE_FLASH_BBT or 16-bit widths */ + info->chip.options = pdata ? pdata->options : 0; + + info->ioaddr = (uint32_t __force) vaddr; + + info->current_cs = info->ioaddr; + info->core_chipsel = pdev->id; + info->mask_chipsel = pdata->mask_chipsel; + + /* use nandboot-capable ALE/CLE masks by default */ + if (pdata && pdata->mask_ale) + info->mask_ale = pdata->mask_cle; + else + info->mask_ale = MASK_ALE; + if (pdata && pdata->mask_cle) + info->mask_cle = pdata->mask_cle; + else + info->mask_cle = MASK_CLE; + + /* Set address of hardware control function */ + info->chip.cmd_ctrl = nand_davinci_hwcontrol; + info->chip.dev_ready = nand_davinci_dev_ready; + + /* Speed up buffer I/O */ + info->chip.read_buf = nand_davinci_read_buf; + info->chip.write_buf = nand_davinci_write_buf; + + /* use board-specific ECC config; else, the best available */ + if (pdata) + ecc_mode = pdata->ecc_mode; + else + ecc_mode = NAND_ECC_HW; + + switch (ecc_mode) { + case NAND_ECC_NONE: + case NAND_ECC_SOFT: + break; + case NAND_ECC_HW: + info->chip.ecc.calculate = nand_davinci_calculate_1bit; + info->chip.ecc.correct = nand_davinci_correct_1bit; + info->chip.ecc.hwctl = nand_davinci_hwctl_1bit; + info->chip.ecc.size = 512; + info->chip.ecc.bytes = 3; + break; + case NAND_ECC_HW_SYNDROME: + /* FIXME implement */ + info->chip.ecc.size = 512; + info->chip.ecc.bytes = 10; + + dev_warn(&pdev->dev, "4-bit ECC nyet supported\n"); + /* FALL THROUGH */ + default: + ret = -EINVAL; + goto err_ecc; + } + info->chip.ecc.mode = ecc_mode; + + info->clk = clk_get(&pdev->dev, "AEMIFCLK"); + if (IS_ERR(info->clk)) { + ret = PTR_ERR(info->clk); + dev_dbg(&pdev->dev, "unable to get AEMIFCLK, err %d\n", ret); + goto err_clk; + } + + ret = clk_enable(info->clk); + if (ret < 0) { + dev_dbg(&pdev->dev, "unable to enable AEMIFCLK, err %d\n", ret); + goto err_clk_enable; + } + + /* EMIF timings should normally be set by the boot loader, + * especially after boot-from-NAND. The *only* reason to + * have this special casing for the DM6446 EVM is to work + * with boot-from-NOR ... with CS0 manually re-jumpered + * (after startup) so it addresses the NAND flash, not NOR. + * Even for dev boards, that's unusually rude... + */ + if (machine_is_davinci_evm()) + nand_dm6446evm_flash_init(info); + + spin_lock_irq(&davinci_nand_lock); + + /* put CSxNAND into NAND mode */ + val = davinci_nand_readl(info, NANDFCR_OFFSET); + val |= BIT(info->core_chipsel); + davinci_nand_writel(info, NANDFCR_OFFSET, val); + + spin_unlock_irq(&davinci_nand_lock); + + /* Scan to find existence of the device(s) */ + ret = nand_scan(&info->mtd, pdata->mask_chipsel ? 2 : 1); + if (ret < 0) { + dev_dbg(&pdev->dev, "no NAND chip(s) found\n"); + goto err_scan; + } + + if (mtd_has_partitions()) { + struct mtd_partition *mtd_parts = NULL; + int mtd_parts_nb = 0; + + if (mtd_has_cmdlinepart()) { + static const char *probes[] __initconst = + { "cmdlinepart", NULL }; + + const char *master_name; + + /* Set info->mtd.name = 0 temporarily */ + master_name = info->mtd.name; + info->mtd.name = (char *)0; + + /* info->mtd.name == 0, means: don't bother checking + <mtd-id> */ + mtd_parts_nb = parse_mtd_partitions(&info->mtd, probes, + &mtd_parts, 0); + + /* Restore info->mtd.name */ + info->mtd.name = master_name; + } + + if (mtd_parts_nb <= 0 && pdata) { + mtd_parts = pdata->parts; + mtd_parts_nb = pdata->nr_parts; + } + + /* Register any partitions */ + if (mtd_parts_nb > 0) { + ret = add_mtd_partitions(&info->mtd, + mtd_parts, mtd_parts_nb); + if (ret == 0) + info->partitioned = true; + } + + } else if (pdata && pdata->nr_parts) { + dev_warn(&pdev->dev, "ignoring %d default partitions on %s\n", + pdata->nr_parts, info->mtd.name); + } + + /* If there's no partition info, just package the whole chip + * as a single MTD device. + */ + if (!info->partitioned) + ret = add_mtd_device(&info->mtd) ? -ENODEV : 0; + + if (ret < 0) + goto err_scan; + + val = davinci_nand_readl(info, NRCSR_OFFSET); + dev_info(&pdev->dev, "controller rev. %d.%d\n", + (val >> 8) & 0xff, val & 0xff); + + return 0; + +err_scan: + clk_disable(info->clk); + +err_clk_enable: + clk_put(info->clk); + +err_ecc: +err_clk: +err_ioremap: + if (base) + iounmap(base); + if (vaddr) + iounmap(vaddr); + +err_nomem: + kfree(info); + return ret; +} + +static int __exit nand_davinci_remove(struct platform_device *pdev) +{ + struct davinci_nand_info *info = platform_get_drvdata(pdev); + int status; + + if (mtd_has_partitions() && info->partitioned) + status = del_mtd_partitions(&info->mtd); + else + status = del_mtd_device(&info->mtd); + + iounmap(info->base); + iounmap(info->vaddr); + + nand_release(&info->mtd); + + clk_disable(info->clk); + clk_put(info->clk); + + kfree(info); + + return 0; +} + +static struct platform_driver nand_davinci_driver = { + .remove = __exit_p(nand_davinci_remove), + .driver = { + .name = "davinci_nand", + }, +}; +MODULE_ALIAS("platform:davinci_nand"); + +static int __init nand_davinci_init(void) +{ + return platform_driver_probe(&nand_davinci_driver, nand_davinci_probe); +} +module_init(nand_davinci_init); + +static void __exit nand_davinci_exit(void) +{ + platform_driver_unregister(&nand_davinci_driver); +} +module_exit(nand_davinci_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Texas Instruments"); +MODULE_DESCRIPTION("Davinci NAND flash driver"); + |