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Diffstat (limited to 'drivers/mtd/nand/raw/davinci_nand.c')
-rw-r--r--drivers/mtd/nand/raw/davinci_nand.c882
1 files changed, 882 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/davinci_nand.c b/drivers/mtd/nand/raw/davinci_nand.c
new file mode 100644
index 000000000000..0f09518d980f
--- /dev/null
+++ b/drivers/mtd/nand/raw/davinci_nand.c
@@ -0,0 +1,882 @@
+/*
+ * 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/module.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/mtd/rawnand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/slab.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+
+#include <linux/platform_data/mtd-davinci.h>
+#include <linux/platform_data/mtd-davinci-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 nand_chip chip;
+
+ 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;
+
+static inline struct davinci_nand_info *to_davinci_nand(struct mtd_info *mtd)
+{
+ return container_of(mtd_to_nand(mtd), struct davinci_nand_info, chip);
+}
+
+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_to_nand(mtd);
+
+ /* 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_to_nand(mtd);
+ 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 -EBADMSG;
+ }
+ } else if (!(diff & (diff - 1))) {
+ /* Single bit ECC error in the ECC itself,
+ * nothing to fix */
+ return 1;
+ } else {
+ /* Uncorrectable error */
+ return -EBADMSG;
+ }
+
+ }
+ 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;
+
+ /* Reset ECC hardware */
+ davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET);
+
+ 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;
+
+ /* 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 -EBADMSG;
+ 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_to_nand(mtd);
+
+ 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_to_nand(mtd);
+
+ 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 int hwecc4_ooblayout_small_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ if (section > 2)
+ return -ERANGE;
+
+ if (!section) {
+ oobregion->offset = 0;
+ oobregion->length = 5;
+ } else if (section == 1) {
+ oobregion->offset = 6;
+ oobregion->length = 2;
+ } else {
+ oobregion->offset = 13;
+ oobregion->length = 3;
+ }
+
+ return 0;
+}
+
+static int hwecc4_ooblayout_small_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ if (section > 1)
+ return -ERANGE;
+
+ if (!section) {
+ oobregion->offset = 8;
+ oobregion->length = 5;
+ } else {
+ oobregion->offset = 16;
+ oobregion->length = mtd->oobsize - 16;
+ }
+
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops hwecc4_small_ooblayout_ops = {
+ .ecc = hwecc4_ooblayout_small_ecc,
+ .free = hwecc4_ooblayout_small_free,
+};
+
+#if defined(CONFIG_OF)
+static const struct of_device_id davinci_nand_of_match[] = {
+ {.compatible = "ti,davinci-nand", },
+ {.compatible = "ti,keystone-nand", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, davinci_nand_of_match);
+
+static struct davinci_nand_pdata
+ *nand_davinci_get_pdata(struct platform_device *pdev)
+{
+ if (!dev_get_platdata(&pdev->dev) && pdev->dev.of_node) {
+ struct davinci_nand_pdata *pdata;
+ const char *mode;
+ u32 prop;
+
+ pdata = devm_kzalloc(&pdev->dev,
+ sizeof(struct davinci_nand_pdata),
+ GFP_KERNEL);
+ pdev->dev.platform_data = pdata;
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+ if (!of_property_read_u32(pdev->dev.of_node,
+ "ti,davinci-chipselect", &prop))
+ pdev->id = prop;
+ else
+ return ERR_PTR(-EINVAL);
+
+ if (!of_property_read_u32(pdev->dev.of_node,
+ "ti,davinci-mask-ale", &prop))
+ pdata->mask_ale = prop;
+ if (!of_property_read_u32(pdev->dev.of_node,
+ "ti,davinci-mask-cle", &prop))
+ pdata->mask_cle = prop;
+ if (!of_property_read_u32(pdev->dev.of_node,
+ "ti,davinci-mask-chipsel", &prop))
+ pdata->mask_chipsel = prop;
+ if (!of_property_read_string(pdev->dev.of_node,
+ "ti,davinci-ecc-mode", &mode)) {
+ if (!strncmp("none", mode, 4))
+ pdata->ecc_mode = NAND_ECC_NONE;
+ if (!strncmp("soft", mode, 4))
+ pdata->ecc_mode = NAND_ECC_SOFT;
+ if (!strncmp("hw", mode, 2))
+ pdata->ecc_mode = NAND_ECC_HW;
+ }
+ if (!of_property_read_u32(pdev->dev.of_node,
+ "ti,davinci-ecc-bits", &prop))
+ pdata->ecc_bits = prop;
+
+ if (!of_property_read_u32(pdev->dev.of_node,
+ "ti,davinci-nand-buswidth", &prop) && prop == 16)
+ pdata->options |= NAND_BUSWIDTH_16;
+
+ if (of_property_read_bool(pdev->dev.of_node,
+ "ti,davinci-nand-use-bbt"))
+ pdata->bbt_options = NAND_BBT_USE_FLASH;
+
+ /*
+ * Since kernel v4.8, this driver has been fixed to enable
+ * use of 4-bit hardware ECC with subpages and verified on
+ * TI's keystone EVMs (K2L, K2HK and K2E).
+ * However, in the interest of not breaking systems using
+ * existing UBI partitions, sub-page writes are not being
+ * (re)enabled. If you want to use subpage writes on Keystone
+ * platforms (i.e. do not have any existing UBI partitions),
+ * then use "ti,davinci-nand" as the compatible in your
+ * device-tree file.
+ */
+ if (of_device_is_compatible(pdev->dev.of_node,
+ "ti,keystone-nand")) {
+ pdata->options |= NAND_NO_SUBPAGE_WRITE;
+ }
+ }
+
+ return dev_get_platdata(&pdev->dev);
+}
+#else
+static struct davinci_nand_pdata
+ *nand_davinci_get_pdata(struct platform_device *pdev)
+{
+ return dev_get_platdata(&pdev->dev);
+}
+#endif
+
+static int nand_davinci_probe(struct platform_device *pdev)
+{
+ struct davinci_nand_pdata *pdata;
+ struct davinci_nand_info *info;
+ struct resource *res1;
+ struct resource *res2;
+ void __iomem *vaddr;
+ void __iomem *base;
+ int ret;
+ uint32_t val;
+ struct mtd_info *mtd;
+
+ pdata = nand_davinci_get_pdata(pdev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+
+ /* 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 = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ 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");
+ return -EINVAL;
+ }
+
+ vaddr = devm_ioremap_resource(&pdev->dev, res1);
+ if (IS_ERR(vaddr))
+ return PTR_ERR(vaddr);
+
+ /*
+ * This registers range is used to setup NAND settings. In case with
+ * TI AEMIF driver, the same memory address range is requested already
+ * by AEMIF, so we cannot request it twice, just ioremap.
+ * The AEMIF and NAND drivers not use the same registers in this range.
+ */
+ base = devm_ioremap(&pdev->dev, res2->start, resource_size(res2));
+ if (!base) {
+ dev_err(&pdev->dev, "ioremap failed for resource %pR\n", res2);
+ return -EADDRNOTAVAIL;
+ }
+
+ info->dev = &pdev->dev;
+ info->base = base;
+ info->vaddr = vaddr;
+
+ mtd = nand_to_mtd(&info->chip);
+ mtd->dev.parent = &pdev->dev;
+ nand_set_flash_node(&info->chip, pdev->dev.of_node);
+
+ 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 */
+ info->chip.ecc.mode = pdata->ecc_mode;
+
+ ret = -EINVAL;
+
+ info->clk = devm_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);
+ return ret;
+ }
+
+ ret = clk_prepare_enable(info->clk);
+ if (ret < 0) {
+ dev_dbg(&pdev->dev, "unable to enable AEMIF clock, err %d\n",
+ ret);
+ goto err_clk_enable;
+ }
+
+ 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(mtd, pdata->mask_chipsel ? 2 : 1, NULL);
+ if (ret < 0) {
+ dev_dbg(&pdev->dev, "no NAND chip(s) found\n");
+ goto err;
+ }
+
+ switch (info->chip.ecc.mode) {
+ case NAND_ECC_NONE:
+ pdata->ecc_bits = 0;
+ break;
+ case NAND_ECC_SOFT:
+ pdata->ecc_bits = 0;
+ /*
+ * This driver expects Hamming based ECC when ecc_mode is set
+ * to NAND_ECC_SOFT. Force ecc.algo to NAND_ECC_HAMMING to
+ * avoid adding an extra ->ecc_algo field to
+ * davinci_nand_pdata.
+ */
+ info->chip.ecc.algo = NAND_ECC_HAMMING;
+ 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)
+ return ret;
+
+ 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;
+ info->chip.ecc.options = NAND_ECC_GENERIC_ERASED_CHECK;
+ info->chip.ecc.algo = NAND_ECC_BCH;
+ } else {
+ /* 1bit ecc hamming */
+ 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.algo = NAND_ECC_HAMMING;
+ }
+ info->chip.ecc.size = 512;
+ info->chip.ecc.strength = pdata->ecc_bits;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* 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 = mtd->writesize / 512;
+
+ if (!chunks || mtd->oobsize < 16) {
+ dev_dbg(&pdev->dev, "too small\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ /* 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) {
+ mtd_set_ooblayout(mtd, &hwecc4_small_ooblayout_ops);
+ } else if (chunks == 4 || chunks == 8) {
+ mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops);
+ info->chip.ecc.mode = NAND_ECC_HW_OOB_FIRST;
+ } else {
+ ret = -EIO;
+ goto err;
+ }
+ }
+
+ ret = nand_scan_tail(mtd);
+ if (ret < 0)
+ goto err;
+
+ if (pdata->parts)
+ ret = mtd_device_parse_register(mtd, NULL, NULL,
+ pdata->parts, pdata->nr_parts);
+ else
+ ret = mtd_device_register(mtd, NULL, 0);
+ if (ret < 0)
+ goto err_cleanup_nand;
+
+ val = davinci_nand_readl(info, NRCSR_OFFSET);
+ dev_info(&pdev->dev, "controller rev. %d.%d\n",
+ (val >> 8) & 0xff, val & 0xff);
+
+ return 0;
+
+err_cleanup_nand:
+ nand_cleanup(&info->chip);
+
+err:
+ clk_disable_unprepare(info->clk);
+
+err_clk_enable:
+ spin_lock_irq(&davinci_nand_lock);
+ if (info->chip.ecc.mode == NAND_ECC_HW_SYNDROME)
+ ecc4_busy = false;
+ spin_unlock_irq(&davinci_nand_lock);
+ return ret;
+}
+
+static int 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);
+
+ nand_release(nand_to_mtd(&info->chip));
+
+ clk_disable_unprepare(info->clk);
+
+ return 0;
+}
+
+static struct platform_driver nand_davinci_driver = {
+ .probe = nand_davinci_probe,
+ .remove = nand_davinci_remove,
+ .driver = {
+ .name = "davinci_nand",
+ .of_match_table = of_match_ptr(davinci_nand_of_match),
+ },
+};
+MODULE_ALIAS("platform:davinci_nand");
+
+module_platform_driver(nand_davinci_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("Davinci NAND flash driver");
+