/*
 * Copyright (C) 2014 Gateworks Corporation
 * Author: Tim Harvey <tharvey@gateworks.com>
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */
#include <common.h>
#include <nand.h>
#include <malloc.h>

static nand_info_t mtd;
static struct nand_chip nand_chip;

static void mxs_nand_command(struct mtd_info *mtd, unsigned int command,
                             int column, int page_addr)
{
        register struct nand_chip *chip = mtd->priv;
        u32 timeo, time_start;

        /* write out the command to the device */
        chip->cmd_ctrl(mtd, command, NAND_CLE);

        /* Serially input address */
        if (column != -1) {
                chip->cmd_ctrl(mtd, column, NAND_ALE);
                chip->cmd_ctrl(mtd, column >> 8, NAND_ALE);
        }
        if (page_addr != -1) {
                chip->cmd_ctrl(mtd, page_addr, NAND_ALE);
                chip->cmd_ctrl(mtd, page_addr >> 8, NAND_ALE);
                /* One more address cycle for devices > 128MiB */
                if (chip->chipsize > (128 << 20))
                        chip->cmd_ctrl(mtd, page_addr >> 16, NAND_ALE);
        }
        chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0);

        if (command == NAND_CMD_READ0) {
                chip->cmd_ctrl(mtd, NAND_CMD_READSTART, NAND_CLE);
                chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0);
        }

        /* wait for nand ready */
        ndelay(100);
        timeo = (CONFIG_SYS_HZ * 20) / 1000;
        time_start = get_timer(0);
        while (get_timer(time_start) < timeo) {
                if (chip->dev_ready(mtd))
                        break;
        }
}

static int mxs_flash_ident(struct mtd_info *mtd)
{
        register struct nand_chip *chip = mtd->priv;
        int i;
        u8 mfg_id, dev_id;
        u8 id_data[8];
        struct nand_onfi_params *p = &chip->onfi_params;

        /* Reset the chip */
        chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);

        /* Send the command for reading device ID */
        chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);

        /* Read manufacturer and device IDs */
        mfg_id = chip->read_byte(mtd);
        dev_id = chip->read_byte(mtd);

        /* Try again to make sure */
        chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
        for (i = 0; i < 8; i++)
                id_data[i] = chip->read_byte(mtd);
        if (id_data[0] != mfg_id || id_data[1] != dev_id) {
                printf("second ID read did not match");
                return -1;
        }
        debug("0x%02x:0x%02x ", mfg_id, dev_id);

        /* read ONFI */
        chip->onfi_version = 0;
        chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);
        if (chip->read_byte(mtd) != 'O' || chip->read_byte(mtd) != 'N' ||
            chip->read_byte(mtd) != 'F' || chip->read_byte(mtd) != 'I') {
                return -2;
        }

        /* we have ONFI, probe it */
        chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
        chip->read_buf(mtd, (uint8_t *)p, sizeof(*p));
        mtd->name = p->model;
        mtd->writesize = le32_to_cpu(p->byte_per_page);
        mtd->erasesize = le32_to_cpu(p->pages_per_block) * mtd->writesize;
        mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
        chip->chipsize = le32_to_cpu(p->blocks_per_lun);
        chip->chipsize *= (uint64_t)mtd->erasesize * p->lun_count;
        /* Calculate the address shift from the page size */
        chip->page_shift = ffs(mtd->writesize) - 1;
        chip->phys_erase_shift = ffs(mtd->erasesize) - 1;
        /* Convert chipsize to number of pages per chip -1 */
        chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
        chip->badblockbits = 8;

        debug("erasesize=%d (>>%d)\n", mtd->erasesize, chip->phys_erase_shift);
        debug("writesize=%d (>>%d)\n", mtd->writesize, chip->page_shift);
        debug("oobsize=%d\n", mtd->oobsize);
        debug("chipsize=%lld\n", chip->chipsize);

        return 0;
}

static int mxs_read_page_ecc(struct mtd_info *mtd, void *buf, unsigned int page)
{
        register struct nand_chip *chip = mtd->priv;
        int ret;

        chip->cmdfunc(mtd, NAND_CMD_READ0, 0x0, page);
        ret = nand_chip.ecc.read_page(mtd, chip, buf, 1, page);
        if (ret < 0) {
                printf("read_page failed %d\n", ret);
                return -1;
        }
        return 0;
}

static int is_badblock(struct mtd_info *mtd, loff_t offs, int allowbbt)
{
        register struct nand_chip *chip = mtd->priv;
        unsigned int block = offs >> chip->phys_erase_shift;
        unsigned int page = offs >> chip->page_shift;

        debug("%s offs=0x%08x block:%d page:%d\n", __func__, (int)offs, block,
              page);
        chip->cmdfunc(mtd, NAND_CMD_READ0, mtd->writesize, page);
        memset(chip->oob_poi, 0, mtd->oobsize);
        chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);

        return chip->oob_poi[0] != 0xff;
}

/* setup mtd and nand structs and init mxs_nand driver */
static int mxs_nand_init(void)
{
        /* return if already initalized */
        if (nand_chip.numchips)
                return 0;

        /* init mxs nand driver */
        board_nand_init(&nand_chip);
        mtd.priv = &nand_chip;
        /* set mtd functions */
        nand_chip.cmdfunc = mxs_nand_command;
        nand_chip.numchips = 1;

        /* identify flash device */
        puts("NAND : ");
        if (mxs_flash_ident(&mtd)) {
                printf("Failed to identify\n");
                return -1;
        }

        /* allocate and initialize buffers */
        nand_chip.buffers = memalign(ARCH_DMA_MINALIGN,
                                     sizeof(*nand_chip.buffers));
        nand_chip.oob_poi = nand_chip.buffers->databuf + mtd.writesize;
        /* setup flash layout (does not scan as we override that) */
        mtd.size = nand_chip.chipsize;
        nand_chip.scan_bbt(&mtd);

        printf("%llu MiB\n", (mtd.size / (1024 * 1024)));
        return 0;
}

int nand_spl_load_image(uint32_t offs, unsigned int size, void *buf)
{
        struct nand_chip *chip;
        unsigned int page;
        unsigned int nand_page_per_block;
        unsigned int sz = 0;

        if (mxs_nand_init())
                return -ENODEV;
        chip = mtd.priv;
        page = offs >> chip->page_shift;
        nand_page_per_block = mtd.erasesize / mtd.writesize;

        debug("%s offset:0x%08x len:%d page:%d\n", __func__, offs, size, page);

        size = roundup(size, mtd.writesize);
        while (sz < size) {
                if (mxs_read_page_ecc(&mtd, buf, page) < 0)
                        return -1;
                sz += mtd.writesize;
                offs += mtd.writesize;
                page++;
                buf += mtd.writesize;

                /*
                 * Check if we have crossed a block boundary, and if so
                 * check for bad block.
                 */
                if (!(page % nand_page_per_block)) {
                        /*
                         * Yes, new block. See if this block is good. If not,
                         * loop until we find a good block.
                         */
                        while (is_badblock(&mtd, offs, 1)) {
                                page = page + nand_page_per_block;
                                /* Check i we've reached the end of flash. */
                                if (page >= mtd.size >> chip->page_shift)
                                        return -ENOMEM;
                        }
                }
        }

        return 0;
}

int nand_default_bbt(struct mtd_info *mtd)
{
        return 0;
}

void nand_init(void)
{
}

void nand_deselect(void)
{
}