diff options
Diffstat (limited to 'drivers/mtd/nand/davinci_nand.c')
| -rw-r--r-- | drivers/mtd/nand/davinci_nand.c | 838 |
1 files changed, 838 insertions, 0 deletions
diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c new file mode 100644 index 00000000..d94b03c2 --- /dev/null +++ b/drivers/mtd/nand/davinci_nand.c @@ -0,0 +1,838 @@ +/* + * 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 <linux/slab.h> + +#include <mach/nand.h> +#include <mach/aemif.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, as well as 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 nand_ecclayout ecclayout; + + struct device *dev; + struct clk *clk; + + bool is_readmode; + + 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; + + struct davinci_aemif_timing *timing; +}; + +static DEFINE_SPINLOCK(davinci_nand_lock); +static bool ecc4_busy; + +#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; +} + +/*----------------------------------------------------------------------*/ + +/* + * 4-bit hardware ECC ... context maintained over entire AEMIF + * + * This is a syndrome engine, but we avoid NAND_ECC_HW_SYNDROME + * since that forces use of a problematic "infix OOB" layout. + * Among other things, it trashes manufacturer bad block markers. + * Also, and specific to this hardware, it ECC-protects the "prepad" + * in the OOB ... while having ECC protection for parts of OOB would + * seem useful, the current MTD stack sometimes wants to update the + * OOB without recomputing ECC. + */ + +static void nand_davinci_hwctl_4bit(struct mtd_info *mtd, int mode) +{ + struct davinci_nand_info *info = to_davinci_nand(mtd); + unsigned long flags; + u32 val; + + spin_lock_irqsave(&davinci_nand_lock, flags); + + /* Start 4-bit ECC calculation for read/write */ + val = davinci_nand_readl(info, NANDFCR_OFFSET); + val &= ~(0x03 << 4); + val |= (info->core_chipsel << 4) | BIT(12); + davinci_nand_writel(info, NANDFCR_OFFSET, val); + + info->is_readmode = (mode == NAND_ECC_READ); + + spin_unlock_irqrestore(&davinci_nand_lock, flags); +} + +/* Read raw ECC code after writing to NAND. */ +static void +nand_davinci_readecc_4bit(struct davinci_nand_info *info, u32 code[4]) +{ + const u32 mask = 0x03ff03ff; + + code[0] = davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET) & mask; + code[1] = davinci_nand_readl(info, NAND_4BIT_ECC2_OFFSET) & mask; + code[2] = davinci_nand_readl(info, NAND_4BIT_ECC3_OFFSET) & mask; + code[3] = davinci_nand_readl(info, NAND_4BIT_ECC4_OFFSET) & mask; +} + +/* Terminate read ECC; or return ECC (as bytes) of data written to NAND. */ +static int nand_davinci_calculate_4bit(struct mtd_info *mtd, + const u_char *dat, u_char *ecc_code) +{ + struct davinci_nand_info *info = to_davinci_nand(mtd); + u32 raw_ecc[4], *p; + unsigned i; + + /* After a read, terminate ECC calculation by a dummy read + * of some 4-bit ECC register. ECC covers everything that + * was read; correct() just uses the hardware state, so + * ecc_code is not needed. + */ + if (info->is_readmode) { + davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET); + return 0; + } + + /* Pack eight raw 10-bit ecc values into ten bytes, making + * two passes which each convert four values (in upper and + * lower halves of two 32-bit words) into five bytes. The + * ROM boot loader uses this same packing scheme. + */ + nand_davinci_readecc_4bit(info, raw_ecc); + for (i = 0, p = raw_ecc; i < 2; i++, p += 2) { + *ecc_code++ = p[0] & 0xff; + *ecc_code++ = ((p[0] >> 8) & 0x03) | ((p[0] >> 14) & 0xfc); + *ecc_code++ = ((p[0] >> 22) & 0x0f) | ((p[1] << 4) & 0xf0); + *ecc_code++ = ((p[1] >> 4) & 0x3f) | ((p[1] >> 10) & 0xc0); + *ecc_code++ = (p[1] >> 18) & 0xff; + } + + return 0; +} + +/* Correct up to 4 bits in data we just read, using state left in the + * hardware plus the ecc_code computed when it was first written. + */ +static int nand_davinci_correct_4bit(struct mtd_info *mtd, + u_char *data, u_char *ecc_code, u_char *null) +{ + int i; + struct davinci_nand_info *info = to_davinci_nand(mtd); + unsigned short ecc10[8]; + unsigned short *ecc16; + u32 syndrome[4]; + u32 ecc_state; + unsigned num_errors, corrected; + unsigned long timeo; + + /* All bytes 0xff? It's an erased page; ignore its ECC. */ + for (i = 0; i < 10; i++) { + if (ecc_code[i] != 0xff) + goto compare; + } + return 0; + +compare: + /* Unpack ten bytes into eight 10 bit values. We know we're + * little-endian, and use type punning for less shifting/masking. + */ + if (WARN_ON(0x01 & (unsigned) ecc_code)) + return -EINVAL; + ecc16 = (unsigned short *)ecc_code; + + ecc10[0] = (ecc16[0] >> 0) & 0x3ff; + ecc10[1] = ((ecc16[0] >> 10) & 0x3f) | ((ecc16[1] << 6) & 0x3c0); + ecc10[2] = (ecc16[1] >> 4) & 0x3ff; + ecc10[3] = ((ecc16[1] >> 14) & 0x3) | ((ecc16[2] << 2) & 0x3fc); + ecc10[4] = (ecc16[2] >> 8) | ((ecc16[3] << 8) & 0x300); + ecc10[5] = (ecc16[3] >> 2) & 0x3ff; + ecc10[6] = ((ecc16[3] >> 12) & 0xf) | ((ecc16[4] << 4) & 0x3f0); + ecc10[7] = (ecc16[4] >> 6) & 0x3ff; + + /* Tell ECC controller about the expected ECC codes. */ + for (i = 7; i >= 0; i--) + davinci_nand_writel(info, NAND_4BIT_ECC_LOAD_OFFSET, ecc10[i]); + + /* Allow time for syndrome calculation ... then read it. + * A syndrome of all zeroes 0 means no detected errors. + */ + davinci_nand_readl(info, NANDFSR_OFFSET); + nand_davinci_readecc_4bit(info, syndrome); + if (!(syndrome[0] | syndrome[1] | syndrome[2] | syndrome[3])) + return 0; + + /* + * Clear any previous address calculation by doing a dummy read of an + * error address register. + */ + davinci_nand_readl(info, NAND_ERR_ADD1_OFFSET); + + /* Start address calculation, and wait for it to complete. + * We _could_ start reading more data while this is working, + * to speed up the overall page read. + */ + davinci_nand_writel(info, NANDFCR_OFFSET, + davinci_nand_readl(info, NANDFCR_OFFSET) | BIT(13)); + + /* + * ECC_STATE field reads 0x3 (Error correction complete) immediately + * after setting the 4BITECC_ADD_CALC_START bit. So if you immediately + * begin trying to poll for the state, you may fall right out of your + * loop without any of the correction calculations having taken place. + * The recommendation from the hardware team is to initially delay as + * long as ECC_STATE reads less than 4. After that, ECC HW has entered + * correction state. + */ + timeo = jiffies + usecs_to_jiffies(100); + do { + ecc_state = (davinci_nand_readl(info, + NANDFSR_OFFSET) >> 8) & 0x0f; + cpu_relax(); + } while ((ecc_state < 4) && time_before(jiffies, timeo)); + + for (;;) { + u32 fsr = davinci_nand_readl(info, NANDFSR_OFFSET); + + switch ((fsr >> 8) & 0x0f) { + case 0: /* no error, should not happen */ + davinci_nand_readl(info, NAND_ERR_ERRVAL1_OFFSET); + return 0; + case 1: /* five or more errors detected */ + davinci_nand_readl(info, NAND_ERR_ERRVAL1_OFFSET); + return -EIO; + case 2: /* error addresses computed */ + case 3: + num_errors = 1 + ((fsr >> 16) & 0x03); + goto correct; + default: /* still working on it */ + cpu_relax(); + continue; + } + } + +correct: + /* correct each error */ + for (i = 0, corrected = 0; i < num_errors; i++) { + int error_address, error_value; + + if (i > 1) { + error_address = davinci_nand_readl(info, + NAND_ERR_ADD2_OFFSET); + error_value = davinci_nand_readl(info, + NAND_ERR_ERRVAL2_OFFSET); + } else { + error_address = davinci_nand_readl(info, + NAND_ERR_ADD1_OFFSET); + error_value = davinci_nand_readl(info, + NAND_ERR_ERRVAL1_OFFSET); + } + + if (i & 1) { + error_address >>= 16; + error_value >>= 16; + } + error_address &= 0x3ff; + error_address = (512 + 7) - error_address; + + if (error_address < 512) { + data[error_address] ^= error_value; + corrected++; + } + } + + return corrected; +} + +/*----------------------------------------------------------------------*/ + +/* + * 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); +} + +/*----------------------------------------------------------------------*/ + +/* An ECC layout for using 4-bit ECC with small-page flash, storing + * ten ECC bytes plus the manufacturer's bad block marker byte, and + * and not overlapping the default BBT markers. + */ +static struct nand_ecclayout hwecc4_small __initconst = { + .eccbytes = 10, + .eccpos = { 0, 1, 2, 3, 4, + /* offset 5 holds the badblock marker */ + 6, 7, + 13, 14, 15, }, + .oobfree = { + {.offset = 8, .length = 5, }, + {.offset = 16, }, + }, +}; + +/* An ECC layout for using 4-bit ECC with large-page (2048bytes) flash, + * storing ten ECC bytes plus the manufacturer's bad block marker byte, + * and not overlapping the default BBT markers. + */ +static struct nand_ecclayout hwecc4_2048 __initconst = { + .eccbytes = 40, + .eccpos = { + /* at the end of spare sector */ + 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, + 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, + 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, + 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, + }, + .oobfree = { + /* 2 bytes at offset 0 hold manufacturer badblock markers */ + {.offset = 2, .length = 22, }, + /* 5 bytes at offset 8 hold BBT markers */ + /* 8 bytes at offset 16 hold JFFS2 clean markers */ + }, +}; + +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; + + /* insist on board-specific configuration */ + if (!pdata) + return -ENODEV; + + /* 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, resource_size(res1)); + base = ioremap(res2->start, resource_size(res2)); + 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_BBT_USE_FLASH */ + info->chip.bbt_options = pdata->bbt_options; + /* options such as 16-bit widths */ + info->chip.options = pdata->options; + info->chip.bbt_td = pdata->bbt_td; + info->chip.bbt_md = pdata->bbt_md; + info->timing = pdata->timing; + + 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 */ + info->mask_ale = pdata->mask_ale ? : MASK_ALE; + info->mask_cle = pdata->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 */ + ecc_mode = pdata->ecc_mode; + + ret = -EINVAL; + switch (ecc_mode) { + case NAND_ECC_NONE: + case NAND_ECC_SOFT: + pdata->ecc_bits = 0; + break; + case NAND_ECC_HW: + if (pdata->ecc_bits == 4) { + /* No sanity checks: CPUs must support this, + * and the chips may not use NAND_BUSWIDTH_16. + */ + + /* No sharing 4-bit hardware between chipselects yet */ + spin_lock_irq(&davinci_nand_lock); + if (ecc4_busy) + ret = -EBUSY; + else + ecc4_busy = true; + spin_unlock_irq(&davinci_nand_lock); + + if (ret == -EBUSY) + goto err_ecc; + + info->chip.ecc.calculate = nand_davinci_calculate_4bit; + info->chip.ecc.correct = nand_davinci_correct_4bit; + info->chip.ecc.hwctl = nand_davinci_hwctl_4bit; + info->chip.ecc.bytes = 10; + } else { + 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.bytes = 3; + } + info->chip.ecc.size = 512; + info->chip.ecc.strength = pdata->ecc_bits; + break; + default: + ret = -EINVAL; + goto err_ecc; + } + info->chip.ecc.mode = ecc_mode; + + info->clk = clk_get(&pdev->dev, "aemif"); + if (IS_ERR(info->clk)) { + ret = PTR_ERR(info->clk); + dev_dbg(&pdev->dev, "unable to get AEMIF clock, err %d\n", ret); + goto err_clk; + } + + ret = clk_enable(info->clk); + if (ret < 0) { + dev_dbg(&pdev->dev, "unable to enable AEMIF clock, err %d\n", + ret); + goto err_clk_enable; + } + + /* + * Setup Async configuration register in case we did not boot from + * NAND and so bootloader did not bother to set it up. + */ + val = davinci_nand_readl(info, A1CR_OFFSET + info->core_chipsel * 4); + + /* Extended Wait is not valid and Select Strobe mode is not used */ + val &= ~(ACR_ASIZE_MASK | ACR_EW_MASK | ACR_SS_MASK); + if (info->chip.options & NAND_BUSWIDTH_16) + val |= 0x1; + + davinci_nand_writel(info, A1CR_OFFSET + info->core_chipsel * 4, val); + + ret = 0; + if (info->timing) + ret = davinci_aemif_setup_timing(info->timing, info->base, + info->core_chipsel); + if (ret < 0) { + dev_dbg(&pdev->dev, "NAND timing values setup fail\n"); + goto err_timing; + } + + 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_ident(&info->mtd, pdata->mask_chipsel ? 2 : 1, NULL); + if (ret < 0) { + dev_dbg(&pdev->dev, "no NAND chip(s) found\n"); + goto err_scan; + } + + /* Update ECC layout if needed ... for 1-bit HW ECC, the default + * is OK, but it allocates 6 bytes when only 3 are needed (for + * each 512 bytes). For the 4-bit HW ECC, that default is not + * usable: 10 bytes are needed, not 6. + */ + if (pdata->ecc_bits == 4) { + int chunks = info->mtd.writesize / 512; + + if (!chunks || info->mtd.oobsize < 16) { + dev_dbg(&pdev->dev, "too small\n"); + ret = -EINVAL; + goto err_scan; + } + + /* For small page chips, preserve the manufacturer's + * badblock marking data ... and make sure a flash BBT + * table marker fits in the free bytes. + */ + if (chunks == 1) { + info->ecclayout = hwecc4_small; + info->ecclayout.oobfree[1].length = + info->mtd.oobsize - 16; + goto syndrome_done; + } + if (chunks == 4) { + info->ecclayout = hwecc4_2048; + info->chip.ecc.mode = NAND_ECC_HW_OOB_FIRST; + goto syndrome_done; + } + + /* 4KiB page chips are not yet supported. The eccpos from + * nand_ecclayout cannot hold 80 bytes and change to eccpos[] + * breaks userspace ioctl interface with mtd-utils. Once we + * resolve this issue, NAND_ECC_HW_OOB_FIRST mode can be used + * for the 4KiB page chips. + * + * TODO: Note that nand_ecclayout has now been expanded and can + * hold plenty of OOB entries. + */ + dev_warn(&pdev->dev, "no 4-bit ECC support yet " + "for 4KiB-page NAND\n"); + ret = -EIO; + goto err_scan; + +syndrome_done: + info->chip.ecc.layout = &info->ecclayout; + } + + ret = nand_scan_tail(&info->mtd); + if (ret < 0) + goto err_scan; + + ret = mtd_device_parse_register(&info->mtd, NULL, NULL, pdata->parts, + pdata->nr_parts); + + 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: +err_timing: + clk_disable(info->clk); + +err_clk_enable: + clk_put(info->clk); + + spin_lock_irq(&davinci_nand_lock); + if (ecc_mode == NAND_ECC_HW_SYNDROME) + ecc4_busy = false; + spin_unlock_irq(&davinci_nand_lock); + +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); + + spin_lock_irq(&davinci_nand_lock); + if (info->chip.ecc.mode == NAND_ECC_HW_SYNDROME) + ecc4_busy = false; + spin_unlock_irq(&davinci_nand_lock); + + 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"); + |