// SPDX-License-Identifier: GPL-2.0+
/*
 * (C) Copyright 2008 Semihalf
 *
 * Written by: Piotr Ziecik <kosmo@semihalf.com>
 */

#include <common.h>
#include <dma.h>
#include <flash.h>
#include <malloc.h>

#include <linux/errno.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/concat.h>
#include <mtd/cfi_flash.h>

static struct mtd_info cfi_mtd_info[CFI_MAX_FLASH_BANKS];
static char cfi_mtd_names[CFI_MAX_FLASH_BANKS][16];
#ifdef CONFIG_MTD_CONCAT
static char c_mtd_name[16];
#endif

static int cfi_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
{
        flash_info_t *fi = mtd->priv;
        size_t a_start = fi->start[0] + instr->addr;
        size_t a_end = a_start + instr->len;
        int s_first = -1;
        int s_last = -1;
        int error, sect;

        for (sect = 0; sect < fi->sector_count; sect++) {
                if (a_start == fi->start[sect])
                        s_first = sect;

                if (sect < fi->sector_count - 1) {
                        if (a_end == fi->start[sect + 1]) {
                                s_last = sect;
                                break;
                        }
                } else {
                        s_last = sect;
                        break;
                }
        }

        if (s_first >= 0 && s_first <= s_last) {
                instr->state = MTD_ERASING;

                flash_set_verbose(0);
                error = flash_erase(fi, s_first, s_last);
                flash_set_verbose(1);

                if (error) {
                        instr->state = MTD_ERASE_FAILED;
                        return -EIO;
                }

                instr->state = MTD_ERASE_DONE;
                return 0;
        }

        return -EINVAL;
}

static int cfi_mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
        size_t *retlen, u_char *buf)
{
        flash_info_t *fi = mtd->priv;
        u_char *f = (u_char*)(fi->start[0]) + from;

        if (dma_memcpy(buf, f, len) < 0)
                memcpy(buf, f, len);
        *retlen = len;

        return 0;
}

static int cfi_mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
        size_t *retlen, const u_char *buf)
{
        flash_info_t *fi = mtd->priv;
        u_long t = fi->start[0] + to;
        int error;

        flash_set_verbose(0);
        error = write_buff(fi, (u_char*)buf, t, len);
        flash_set_verbose(1);

        if (!error) {
                *retlen = len;
                return 0;
        }

        return -EIO;
}

static void cfi_mtd_sync(struct mtd_info *mtd)
{
        /*
         * This function should wait until all pending operations
         * finish. However this driver is fully synchronous, so
         * this function returns immediately
         */
}

static int cfi_mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
        flash_info_t *fi = mtd->priv;

        flash_set_verbose(0);
        flash_protect(FLAG_PROTECT_SET, fi->start[0] + ofs,
                                        fi->start[0] + ofs + len - 1, fi);
        flash_set_verbose(1);

        return 0;
}

static int cfi_mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
        flash_info_t *fi = mtd->priv;

        flash_set_verbose(0);
        flash_protect(FLAG_PROTECT_CLEAR, fi->start[0] + ofs,
                                        fi->start[0] + ofs + len - 1, fi);
        flash_set_verbose(1);

        return 0;
}

static int cfi_mtd_set_erasesize(struct mtd_info *mtd, flash_info_t *fi)
{
        int sect_size = 0;
        int sect_size_old = 0;
        int sect;
        int regions = 0;
        int numblocks = 0;
        ulong offset;
        ulong base_addr;

        /*
         * First detect the number of eraseregions so that we can allocate
         * the array of eraseregions correctly
         */
        for (sect = 0; sect < fi->sector_count; sect++) {
                if (sect_size_old != flash_sector_size(fi, sect))
                        regions++;
                sect_size_old = flash_sector_size(fi, sect);
        }

        switch (regions) {
        case 0:
                return 1;
        case 1: /* flash has uniform erase size */
                mtd->numeraseregions = 0;
                mtd->erasesize = sect_size_old;
                return 0;
        }

        mtd->numeraseregions = regions;
        mtd->eraseregions = malloc(sizeof(struct mtd_erase_region_info) * regions);

        /*
         * Now detect the largest sector and fill the eraseregions
         */
        regions = 0;
        base_addr = offset = fi->start[0];
        sect_size_old = flash_sector_size(fi, 0);
        for (sect = 0; sect < fi->sector_count; sect++) {
                if (sect_size_old != flash_sector_size(fi, sect)) {
                        mtd->eraseregions[regions].offset = offset - base_addr;
                        mtd->eraseregions[regions].erasesize = sect_size_old;
                        mtd->eraseregions[regions].numblocks = numblocks;
                        /* Now start counting the next eraseregions */
                        numblocks = 0;
                        regions++;
                        offset = fi->start[sect];
                }
                numblocks++;

                /*
                 * Select the largest sector size as erasesize (e.g. for UBI)
                 */
                if (flash_sector_size(fi, sect) > sect_size)
                        sect_size = flash_sector_size(fi, sect);

                sect_size_old = flash_sector_size(fi, sect);
        }

        /*
         * Set the last region
         */
        mtd->eraseregions[regions].offset = offset - base_addr;
        mtd->eraseregions[regions].erasesize = sect_size_old;
        mtd->eraseregions[regions].numblocks = numblocks;

        mtd->erasesize = sect_size;

        return 0;
}

int cfi_mtd_init(void)
{
        struct mtd_info *mtd;
        flash_info_t *fi;
        int error, i;
#ifdef CONFIG_MTD_CONCAT
        int devices_found = 0;
        struct mtd_info *mtd_list[CFI_FLASH_BANKS];
#endif

        for (i = 0; i < CFI_FLASH_BANKS; i++) {
                fi = &flash_info[i];
                mtd = &cfi_mtd_info[i];

                memset(mtd, 0, sizeof(struct mtd_info));

                error = cfi_mtd_set_erasesize(mtd, fi);
                if (error)
                        continue;

                sprintf(cfi_mtd_names[i], "nor%d", i);
#ifdef CONFIG_CFI_FLASH
                mtd->dev                = fi->dev;
#endif
                mtd->name               = cfi_mtd_names[i];
                mtd->type               = MTD_NORFLASH;
                mtd->flags              = MTD_CAP_NORFLASH;
                mtd->size               = fi->size;
                mtd->writesize          = 1;
                mtd->writebufsize       = mtd->writesize;

                mtd->_erase             = cfi_mtd_erase;
                mtd->_read              = cfi_mtd_read;
                mtd->_write             = cfi_mtd_write;
                mtd->_sync              = cfi_mtd_sync;
                mtd->_lock              = cfi_mtd_lock;
                mtd->_unlock            = cfi_mtd_unlock;
                mtd->priv               = fi;

                if (add_mtd_device(mtd))
                        return -ENOMEM;

#ifdef CONFIG_MTD_CONCAT
                mtd_list[devices_found++] = mtd;
#endif
        }

#ifdef CONFIG_MTD_CONCAT
        if (devices_found > 1) {
                /*
                 * We detected multiple devices. Concatenate them together.
                 */
                sprintf(c_mtd_name, "nor%d", devices_found);
                mtd = mtd_concat_create(mtd_list, devices_found, c_mtd_name);

                if (mtd == NULL)
                        return -ENXIO;

                if (add_mtd_device(mtd))
                        return -ENOMEM;
        }
#endif /* CONFIG_MTD_CONCAT */

        return 0;
}