--- /dev/null
+/*
+ * 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/cpu.h>
+#include <mach/nand.h>
+
+#include <asm/mach-types.h>
+
+
+#ifdef CONFIG_MTD_PARTITIONS
+static inline int mtd_has_partitions(void) { return 1; }
+#else
+static inline int mtd_has_partitions(void) { return 0; }
+#endif
+
+#ifdef CONFIG_MTD_CMDLINE_PARTS
+static inline int mtd_has_cmdlinepart(void) { return 1; }
+#else
+static inline int mtd_has_cmdlinepart(void) { return 0; }
+#endif
+
+
+/*
+ * 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->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 if (cpu_is_davinci_dm355())
+ ecc_mode = NAND_ECC_HW_SYNDROME;
+ 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");
+