/* * JZ4780 NAND driver * * Copyright (c) 2015 Imagination Technologies * Author: Alex Smith * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "jz4780_bch.h" #define DRV_NAME "jz4780-nand" #define OFFSET_DATA 0x00000000 #define OFFSET_CMD 0x00400000 #define OFFSET_ADDR 0x00800000 /* Command delay when there is no R/B pin. */ #define RB_DELAY_US 100 struct jz4780_nand_cs { unsigned int bank; void __iomem *base; }; struct jz4780_nand_controller { struct device *dev; struct jz4780_bch *bch; struct nand_controller controller; unsigned int num_banks; struct list_head chips; int selected; struct jz4780_nand_cs cs[]; }; struct jz4780_nand_chip { struct nand_chip chip; struct list_head chip_list; struct gpio_desc *busy_gpio; struct gpio_desc *wp_gpio; unsigned int reading: 1; }; static inline struct jz4780_nand_chip *to_jz4780_nand_chip(struct mtd_info *mtd) { return container_of(mtd_to_nand(mtd), struct jz4780_nand_chip, chip); } static inline struct jz4780_nand_controller *to_jz4780_nand_controller(struct nand_controller *ctrl) { return container_of(ctrl, struct jz4780_nand_controller, controller); } static void jz4780_nand_select_chip(struct mtd_info *mtd, int chipnr) { struct jz4780_nand_chip *nand = to_jz4780_nand_chip(mtd); struct jz4780_nand_controller *nfc = to_jz4780_nand_controller(nand->chip.controller); struct jz4780_nand_cs *cs; /* Ensure the currently selected chip is deasserted. */ if (chipnr == -1 && nfc->selected >= 0) { cs = &nfc->cs[nfc->selected]; jz4780_nemc_assert(nfc->dev, cs->bank, false); } nfc->selected = chipnr; } static void jz4780_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl) { struct jz4780_nand_chip *nand = to_jz4780_nand_chip(mtd); struct jz4780_nand_controller *nfc = to_jz4780_nand_controller(nand->chip.controller); struct jz4780_nand_cs *cs; if (WARN_ON(nfc->selected < 0)) return; cs = &nfc->cs[nfc->selected]; jz4780_nemc_assert(nfc->dev, cs->bank, ctrl & NAND_NCE); if (cmd == NAND_CMD_NONE) return; if (ctrl & NAND_ALE) writeb(cmd, cs->base + OFFSET_ADDR); else if (ctrl & NAND_CLE) writeb(cmd, cs->base + OFFSET_CMD); } static int jz4780_nand_dev_ready(struct mtd_info *mtd) { struct jz4780_nand_chip *nand = to_jz4780_nand_chip(mtd); return !gpiod_get_value_cansleep(nand->busy_gpio); } static void jz4780_nand_ecc_hwctl(struct mtd_info *mtd, int mode) { struct jz4780_nand_chip *nand = to_jz4780_nand_chip(mtd); nand->reading = (mode == NAND_ECC_READ); } static int jz4780_nand_ecc_calculate(struct mtd_info *mtd, const u8 *dat, u8 *ecc_code) { struct jz4780_nand_chip *nand = to_jz4780_nand_chip(mtd); struct jz4780_nand_controller *nfc = to_jz4780_nand_controller(nand->chip.controller); struct jz4780_bch_params params; /* * Don't need to generate the ECC when reading, BCH does it for us as * part of decoding/correction. */ if (nand->reading) return 0; params.size = nand->chip.ecc.size; params.bytes = nand->chip.ecc.bytes; params.strength = nand->chip.ecc.strength; return jz4780_bch_calculate(nfc->bch, ¶ms, dat, ecc_code); } static int jz4780_nand_ecc_correct(struct mtd_info *mtd, u8 *dat, u8 *read_ecc, u8 *calc_ecc) { struct jz4780_nand_chip *nand = to_jz4780_nand_chip(mtd); struct jz4780_nand_controller *nfc = to_jz4780_nand_controller(nand->chip.controller); struct jz4780_bch_params params; params.size = nand->chip.ecc.size; params.bytes = nand->chip.ecc.bytes; params.strength = nand->chip.ecc.strength; return jz4780_bch_correct(nfc->bch, ¶ms, dat, read_ecc); } static int jz4780_nand_attach_chip(struct nand_chip *chip) { struct mtd_info *mtd = nand_to_mtd(chip); struct jz4780_nand_controller *nfc = to_jz4780_nand_controller(chip->controller); int eccbytes; chip->ecc.bytes = fls((1 + 8) * chip->ecc.size) * (chip->ecc.strength / 8); switch (chip->ecc.mode) { case NAND_ECC_HW: if (!nfc->bch) { dev_err(nfc->dev, "HW BCH selected, but BCH controller not found\n"); return -ENODEV; } chip->ecc.hwctl = jz4780_nand_ecc_hwctl; chip->ecc.calculate = jz4780_nand_ecc_calculate; chip->ecc.correct = jz4780_nand_ecc_correct; /* fall through */ case NAND_ECC_SOFT: dev_info(nfc->dev, "using %s (strength %d, size %d, bytes %d)\n", (nfc->bch) ? "hardware BCH" : "software ECC", chip->ecc.strength, chip->ecc.size, chip->ecc.bytes); break; case NAND_ECC_NONE: dev_info(nfc->dev, "not using ECC\n"); break; default: dev_err(nfc->dev, "ECC mode %d not supported\n", chip->ecc.mode); return -EINVAL; } /* The NAND core will generate the ECC layout for SW ECC */ if (chip->ecc.mode != NAND_ECC_HW) return 0; /* Generate ECC layout. ECC codes are right aligned in the OOB area. */ eccbytes = mtd->writesize / chip->ecc.size * chip->ecc.bytes; if (eccbytes > mtd->oobsize - 2) { dev_err(nfc->dev, "invalid ECC config: required %d ECC bytes, but only %d are available", eccbytes, mtd->oobsize - 2); return -EINVAL; } mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops); return 0; } static const struct nand_controller_ops jz4780_nand_controller_ops = { .attach_chip = jz4780_nand_attach_chip, }; static int jz4780_nand_init_chip(struct platform_device *pdev, struct jz4780_nand_controller *nfc, struct device_node *np, unsigned int chipnr) { struct device *dev = &pdev->dev; struct jz4780_nand_chip *nand; struct jz4780_nand_cs *cs; struct resource *res; struct nand_chip *chip; struct mtd_info *mtd; const __be32 *reg; int ret = 0; cs = &nfc->cs[chipnr]; reg = of_get_property(np, "reg", NULL); if (!reg) return -EINVAL; cs->bank = be32_to_cpu(*reg); jz4780_nemc_set_type(nfc->dev, cs->bank, JZ4780_NEMC_BANK_NAND); res = platform_get_resource(pdev, IORESOURCE_MEM, chipnr); cs->base = devm_ioremap_resource(dev, res); if (IS_ERR(cs->base)) return PTR_ERR(cs->base); nand = devm_kzalloc(dev, sizeof(*nand), GFP_KERNEL); if (!nand) return -ENOMEM; nand->busy_gpio = devm_gpiod_get_optional(dev, "rb", GPIOD_IN); if (IS_ERR(nand->busy_gpio)) { ret = PTR_ERR(nand->busy_gpio); dev_err(dev, "failed to request busy GPIO: %d\n", ret); return ret; } else if (nand->busy_gpio) { nand->chip.dev_ready = jz4780_nand_dev_ready; } nand->wp_gpio = devm_gpiod_get_optional(dev, "wp", GPIOD_OUT_LOW); if (IS_ERR(nand->wp_gpio)) { ret = PTR_ERR(nand->wp_gpio); dev_err(dev, "failed to request WP GPIO: %d\n", ret); return ret; } chip = &nand->chip; mtd = nand_to_mtd(chip); mtd->name = devm_kasprintf(dev, GFP_KERNEL, "%s.%d", dev_name(dev), cs->bank); if (!mtd->name) return -ENOMEM; mtd->dev.parent = dev; chip->IO_ADDR_R = cs->base + OFFSET_DATA; chip->IO_ADDR_W = cs->base + OFFSET_DATA; chip->chip_delay = RB_DELAY_US; chip->options = NAND_NO_SUBPAGE_WRITE; chip->select_chip = jz4780_nand_select_chip; chip->cmd_ctrl = jz4780_nand_cmd_ctrl; chip->ecc.mode = NAND_ECC_HW; chip->controller = &nfc->controller; nand_set_flash_node(chip, np); chip->controller->ops = &jz4780_nand_controller_ops; ret = nand_scan(chip, 1); if (ret) return ret; ret = mtd_device_register(mtd, NULL, 0); if (ret) { nand_release(chip); return ret; } list_add_tail(&nand->chip_list, &nfc->chips); return 0; } static void jz4780_nand_cleanup_chips(struct jz4780_nand_controller *nfc) { struct jz4780_nand_chip *chip; while (!list_empty(&nfc->chips)) { chip = list_first_entry(&nfc->chips, struct jz4780_nand_chip, chip_list); nand_release(&chip->chip); list_del(&chip->chip_list); } } static int jz4780_nand_init_chips(struct jz4780_nand_controller *nfc, struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *np; int i = 0; int ret; int num_chips = of_get_child_count(dev->of_node); if (num_chips > nfc->num_banks) { dev_err(dev, "found %d chips but only %d banks\n", num_chips, nfc->num_banks); return -EINVAL; } for_each_child_of_node(dev->of_node, np) { ret = jz4780_nand_init_chip(pdev, nfc, np, i); if (ret) { jz4780_nand_cleanup_chips(nfc); return ret; } i++; } return 0; } static int jz4780_nand_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; unsigned int num_banks; struct jz4780_nand_controller *nfc; int ret; num_banks = jz4780_nemc_num_banks(dev); if (num_banks == 0) { dev_err(dev, "no banks found\n"); return -ENODEV; } nfc = devm_kzalloc(dev, sizeof(*nfc) + (sizeof(nfc->cs[0]) * num_banks), GFP_KERNEL); if (!nfc) return -ENOMEM; /* * Check for BCH HW before we call nand_scan_ident, to prevent us from * having to call it again if the BCH driver returns -EPROBE_DEFER. */ nfc->bch = of_jz4780_bch_get(dev->of_node); if (IS_ERR(nfc->bch)) return PTR_ERR(nfc->bch); nfc->dev = dev; nfc->num_banks = num_banks; nand_controller_init(&nfc->controller); INIT_LIST_HEAD(&nfc->chips); ret = jz4780_nand_init_chips(nfc, pdev); if (ret) { if (nfc->bch) jz4780_bch_release(nfc->bch); return ret; } platform_set_drvdata(pdev, nfc); return 0; } static int jz4780_nand_remove(struct platform_device *pdev) { struct jz4780_nand_controller *nfc = platform_get_drvdata(pdev); if (nfc->bch) jz4780_bch_release(nfc->bch); jz4780_nand_cleanup_chips(nfc); return 0; } static const struct of_device_id jz4780_nand_dt_match[] = { { .compatible = "ingenic,jz4780-nand" }, {}, }; MODULE_DEVICE_TABLE(of, jz4780_nand_dt_match); static struct platform_driver jz4780_nand_driver = { .probe = jz4780_nand_probe, .remove = jz4780_nand_remove, .driver = { .name = DRV_NAME, .of_match_table = of_match_ptr(jz4780_nand_dt_match), }, }; module_platform_driver(jz4780_nand_driver); MODULE_AUTHOR("Alex Smith "); MODULE_AUTHOR("Harvey Hunt "); MODULE_DESCRIPTION("Ingenic JZ4780 NAND driver"); MODULE_LICENSE("GPL v2");