// SPDX-License-Identifier: GPL-2.0
/*
 *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
 *                2002-2006 Thomas Gleixner (tglx@kernel.org)
 *
 *  Credits:
 *      David Woodhouse for adding multichip support
 *
 *      Aleph One Ltd. and Toby Churchill Ltd. for supporting the
 *      rework for 2K page size chips
 *
 * This file contains all ONFI helpers.
 */

#include <linux/slab.h>

#include "internals.h"

#define JEDEC_PARAM_PAGES 3

/*
 * Check if the NAND chip is JEDEC compliant, returns 1 if it is, 0 otherwise.
 */
int nand_jedec_detect(struct nand_chip *chip)
{
        struct nand_device *base = &chip->base;
        struct mtd_info *mtd = nand_to_mtd(chip);
        struct nand_memory_organization *memorg;
        struct nand_jedec_params *p;
        struct jedec_ecc_info *ecc;
        bool use_datain = false;
        int jedec_version = 0;
        char id[5];
        int i, val, ret;
        u16 crc;

        memorg = nanddev_get_memorg(&chip->base);

        /* Try JEDEC for unknown chip or LP */
        ret = nand_readid_op(chip, 0x40, id, sizeof(id));
        if (ret || strncmp(id, "JEDEC", sizeof(id)))
                return 0;

        /* JEDEC chip: allocate a buffer to hold its parameter page */
        p = kzalloc_obj(*p);
        if (!p)
                return -ENOMEM;

        if (!nand_has_exec_op(chip) || chip->controller->supported_op.data_only_read)
                use_datain = true;

        for (i = 0; i < JEDEC_PARAM_PAGES; i++) {
                if (!i)
                        ret = nand_read_param_page_op(chip, 0x40, p,
                                                      sizeof(*p));
                else if (use_datain)
                        ret = nand_read_data_op(chip, p, sizeof(*p), true,
                                                false);
                else
                        ret = nand_change_read_column_op(chip, sizeof(*p) * i,
                                                         p, sizeof(*p), true);
                if (ret) {
                        ret = 0;
                        goto free_jedec_param_page;
                }

                crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)p, 510);
                if (crc == le16_to_cpu(p->crc))
                        break;
        }

        if (i == JEDEC_PARAM_PAGES) {
                pr_err("Could not find valid JEDEC parameter page; aborting\n");
                goto free_jedec_param_page;
        }

        /* Check version */
        val = le16_to_cpu(p->revision);
        if (val & (1 << 2))
                jedec_version = 10;
        else if (val & (1 << 1))
                jedec_version = 1; /* vendor specific version */

        if (!jedec_version) {
                pr_info("unsupported JEDEC version: %d\n", val);
                goto free_jedec_param_page;
        }

        sanitize_string(p->manufacturer, sizeof(p->manufacturer));
        sanitize_string(p->model, sizeof(p->model));
        chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
        if (!chip->parameters.model) {
                ret = -ENOMEM;
                goto free_jedec_param_page;
        }

        if (p->opt_cmd[0] & JEDEC_OPT_CMD_READ_CACHE)
                chip->parameters.supports_read_cache = true;

        memorg->pagesize = le32_to_cpu(p->byte_per_page);
        mtd->writesize = memorg->pagesize;

        /* Please reference to the comment for nand_flash_detect_onfi. */
        memorg->pages_per_eraseblock =
                        1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
        mtd->erasesize = memorg->pages_per_eraseblock * memorg->pagesize;

        memorg->oobsize = le16_to_cpu(p->spare_bytes_per_page);
        mtd->oobsize = memorg->oobsize;

        memorg->luns_per_target = p->lun_count;
        memorg->planes_per_lun = 1 << p->multi_plane_addr;

        /* Please reference to the comment for nand_flash_detect_onfi. */
        memorg->eraseblocks_per_lun =
                1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
        memorg->bits_per_cell = p->bits_per_cell;

        if (le16_to_cpu(p->features) & JEDEC_FEATURE_16_BIT_BUS)
                chip->options |= NAND_BUSWIDTH_16;

        /* ECC info */
        ecc = &p->ecc_info[0];

        if (ecc->codeword_size >= 9) {
                struct nand_ecc_props requirements = {
                        .strength = ecc->ecc_bits,
                        .step_size = 1 << ecc->codeword_size,
                };

                nanddev_set_ecc_requirements(base, &requirements);
        } else {
                pr_warn("Invalid codeword size\n");
        }

        ret = 1;

free_jedec_param_page:
        kfree(p);
        return ret;
}