diff options
Diffstat (limited to 'drivers/mtd/nand/raw/ndfc.c')
| -rw-r--r-- | drivers/mtd/nand/raw/ndfc.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/ndfc.c b/drivers/mtd/nand/raw/ndfc.c new file mode 100644 index 000000000..338d6b1a1 --- /dev/null +++ b/drivers/mtd/nand/raw/ndfc.c @@ -0,0 +1,277 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Overview: + * Platform independent driver for NDFC (NanD Flash Controller) + * integrated into EP440 cores + * + * Ported to an OF platform driver by Sean MacLennan + * + * The NDFC supports multiple chips, but this driver only supports a + * single chip since I do not have access to any boards with + * multiple chips. + * + * Author: Thomas Gleixner + * + * Copyright 2006 IBM + * Copyright 2008 PIKA Technologies + * Sean MacLennan <smaclennan@pikatech.com> + */ +#include <linux/module.h> +#include <linux/mtd/rawnand.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/ndfc.h> +#include <linux/slab.h> +#include <linux/mtd/mtd.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> +#include <asm/io.h> + +#define NDFC_MAX_CS 4 + +struct ndfc_controller { + struct platform_device *ofdev; + void __iomem *ndfcbase; + struct nand_chip chip; + int chip_select; + struct nand_controller ndfc_control; +}; + +static struct ndfc_controller ndfc_ctrl[NDFC_MAX_CS]; + +static void ndfc_select_chip(struct nand_chip *nchip, int chip) +{ + uint32_t ccr; + struct ndfc_controller *ndfc = nand_get_controller_data(nchip); + + ccr = in_be32(ndfc->ndfcbase + NDFC_CCR); + if (chip >= 0) { + ccr &= ~NDFC_CCR_BS_MASK; + ccr |= NDFC_CCR_BS(chip + ndfc->chip_select); + } else + ccr |= NDFC_CCR_RESET_CE; + out_be32(ndfc->ndfcbase + NDFC_CCR, ccr); +} + +static void ndfc_hwcontrol(struct nand_chip *chip, int cmd, unsigned int ctrl) +{ + struct ndfc_controller *ndfc = nand_get_controller_data(chip); + + if (cmd == NAND_CMD_NONE) + return; + + if (ctrl & NAND_CLE) + writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_CMD); + else + writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_ALE); +} + +static int ndfc_ready(struct nand_chip *chip) +{ + struct ndfc_controller *ndfc = nand_get_controller_data(chip); + + return in_be32(ndfc->ndfcbase + NDFC_STAT) & NDFC_STAT_IS_READY; +} + +static void ndfc_enable_hwecc(struct nand_chip *chip, int mode) +{ + uint32_t ccr; + struct ndfc_controller *ndfc = nand_get_controller_data(chip); + + ccr = in_be32(ndfc->ndfcbase + NDFC_CCR); + ccr |= NDFC_CCR_RESET_ECC; + out_be32(ndfc->ndfcbase + NDFC_CCR, ccr); + wmb(); +} + +static int ndfc_calculate_ecc(struct nand_chip *chip, + const u_char *dat, u_char *ecc_code) +{ + struct ndfc_controller *ndfc = nand_get_controller_data(chip); + uint32_t ecc; + uint8_t *p = (uint8_t *)&ecc; + + wmb(); + ecc = in_be32(ndfc->ndfcbase + NDFC_ECC); + /* The NDFC uses Smart Media (SMC) bytes order */ + ecc_code[0] = p[1]; + ecc_code[1] = p[2]; + ecc_code[2] = p[3]; + + return 0; +} + +/* + * Speedups for buffer read/write/verify + * + * NDFC allows 32bit read/write of data. So we can speed up the buffer + * functions. No further checking, as nand_base will always read/write + * page aligned. + */ +static void ndfc_read_buf(struct nand_chip *chip, uint8_t *buf, int len) +{ + struct ndfc_controller *ndfc = nand_get_controller_data(chip); + uint32_t *p = (uint32_t *) buf; + + for(;len > 0; len -= 4) + *p++ = in_be32(ndfc->ndfcbase + NDFC_DATA); +} + +static void ndfc_write_buf(struct nand_chip *chip, const uint8_t *buf, int len) +{ + struct ndfc_controller *ndfc = nand_get_controller_data(chip); + uint32_t *p = (uint32_t *) buf; + + for(;len > 0; len -= 4) + out_be32(ndfc->ndfcbase + NDFC_DATA, *p++); +} + +/* + * Initialize chip structure + */ +static int ndfc_chip_init(struct ndfc_controller *ndfc, + struct device_node *node) +{ + struct device_node *flash_np; + struct nand_chip *chip = &ndfc->chip; + struct mtd_info *mtd = nand_to_mtd(chip); + int ret; + + chip->legacy.IO_ADDR_R = ndfc->ndfcbase + NDFC_DATA; + chip->legacy.IO_ADDR_W = ndfc->ndfcbase + NDFC_DATA; + chip->legacy.cmd_ctrl = ndfc_hwcontrol; + chip->legacy.dev_ready = ndfc_ready; + chip->legacy.select_chip = ndfc_select_chip; + chip->legacy.chip_delay = 50; + chip->controller = &ndfc->ndfc_control; + chip->legacy.read_buf = ndfc_read_buf; + chip->legacy.write_buf = ndfc_write_buf; + chip->ecc.correct = rawnand_sw_hamming_correct; + chip->ecc.hwctl = ndfc_enable_hwecc; + chip->ecc.calculate = ndfc_calculate_ecc; + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; + chip->ecc.size = 256; + chip->ecc.bytes = 3; + chip->ecc.strength = 1; + nand_set_controller_data(chip, ndfc); + + mtd->dev.parent = &ndfc->ofdev->dev; + + flash_np = of_get_next_child(node, NULL); + if (!flash_np) + return -ENODEV; + nand_set_flash_node(chip, flash_np); + + mtd->name = kasprintf(GFP_KERNEL, "%s.%pOFn", dev_name(&ndfc->ofdev->dev), + flash_np); + if (!mtd->name) { + ret = -ENOMEM; + goto err; + } + + ret = nand_scan(chip, 1); + if (ret) + goto err; + + ret = mtd_device_register(mtd, NULL, 0); + +err: + of_node_put(flash_np); + if (ret) + kfree(mtd->name); + return ret; +} + +static int ndfc_probe(struct platform_device *ofdev) +{ + struct ndfc_controller *ndfc; + const __be32 *reg; + u32 ccr; + u32 cs; + int err, len; + + /* Read the reg property to get the chip select */ + reg = of_get_property(ofdev->dev.of_node, "reg", &len); + if (reg == NULL || len != 12) { + dev_err(&ofdev->dev, "unable read reg property (%d)\n", len); + return -ENOENT; + } + + cs = be32_to_cpu(reg[0]); + if (cs >= NDFC_MAX_CS) { + dev_err(&ofdev->dev, "invalid CS number (%d)\n", cs); + return -EINVAL; + } + + ndfc = &ndfc_ctrl[cs]; + ndfc->chip_select = cs; + + nand_controller_init(&ndfc->ndfc_control); + ndfc->ofdev = ofdev; + dev_set_drvdata(&ofdev->dev, ndfc); + + ndfc->ndfcbase = of_iomap(ofdev->dev.of_node, 0); + if (!ndfc->ndfcbase) { + dev_err(&ofdev->dev, "failed to get memory\n"); + return -EIO; + } + + ccr = NDFC_CCR_BS(ndfc->chip_select); + + /* It is ok if ccr does not exist - just default to 0 */ + reg = of_get_property(ofdev->dev.of_node, "ccr", NULL); + if (reg) + ccr |= be32_to_cpup(reg); + + out_be32(ndfc->ndfcbase + NDFC_CCR, ccr); + + /* Set the bank settings if given */ + reg = of_get_property(ofdev->dev.of_node, "bank-settings", NULL); + if (reg) { + int offset = NDFC_BCFG0 + (ndfc->chip_select << 2); + out_be32(ndfc->ndfcbase + offset, be32_to_cpup(reg)); + } + + err = ndfc_chip_init(ndfc, ofdev->dev.of_node); + if (err) { + iounmap(ndfc->ndfcbase); + return err; + } + + return 0; +} + +static int ndfc_remove(struct platform_device *ofdev) +{ + struct ndfc_controller *ndfc = dev_get_drvdata(&ofdev->dev); + struct nand_chip *chip = &ndfc->chip; + struct mtd_info *mtd = nand_to_mtd(chip); + int ret; + + ret = mtd_device_unregister(mtd); + WARN_ON(ret); + nand_cleanup(chip); + kfree(mtd->name); + + return 0; +} + +static const struct of_device_id ndfc_match[] = { + { .compatible = "ibm,ndfc", }, + {} +}; +MODULE_DEVICE_TABLE(of, ndfc_match); + +static struct platform_driver ndfc_driver = { + .driver = { + .name = "ndfc", + .of_match_table = ndfc_match, + }, + .probe = ndfc_probe, + .remove = ndfc_remove, +}; + +module_platform_driver(ndfc_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>"); +MODULE_DESCRIPTION("OF Platform driver for NDFC"); |