/*
 * (C) Copyright 2012
 * Konstantin Kozhevnikov, Cogent Embedded
 *
 * based on nand_spl_simple code
 *
 * (C) Copyright 2006-2008
 * Stefan Roese, DENX Software Engineering, sr@denx.de.
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

#include <common.h>
#include <nand.h>
#include <asm/io.h>
#include <linux/mtd/nand_ecc.h>

static int nand_ecc_pos[] = CONFIG_SYS_NAND_ECCPOS;
static struct mtd_info *mtd;
static struct nand_chip nand_chip;

#define ECCSTEPS        (CONFIG_SYS_NAND_PAGE_SIZE / \
                                        CONFIG_SYS_NAND_ECCSIZE)
#define ECCTOTAL        (ECCSTEPS * CONFIG_SYS_NAND_ECCBYTES)


/*
 * NAND command for large page NAND devices (2k)
 */
static int nand_command(int block, int page, uint32_t offs,
        u8 cmd)
{
        struct nand_chip *this = mtd_to_nand(mtd);
        int page_addr = page + block * CONFIG_SYS_NAND_PAGE_COUNT;
        void (*hwctrl)(struct mtd_info *mtd, int cmd,
                        unsigned int ctrl) = this->cmd_ctrl;

        while (!this->dev_ready(mtd))
                ;

        /* Emulate NAND_CMD_READOOB */
        if (cmd == NAND_CMD_READOOB) {
                offs += CONFIG_SYS_NAND_PAGE_SIZE;
                cmd = NAND_CMD_READ0;
        }

        /* Begin command latch cycle */
        hwctrl(mtd, cmd, NAND_CTRL_CLE | NAND_CTRL_CHANGE);

        if (cmd == NAND_CMD_RESET) {
                hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);

                /*
                 * Apply this short delay always to ensure that we do wait
                 * tWB in any case on any machine.
                 */
                ndelay(150);

                while (!this->dev_ready(mtd))
                        ;
                return 0;
        }

        /* Shift the offset from byte addressing to word addressing. */
        if ((this->options & NAND_BUSWIDTH_16) && !nand_opcode_8bits(cmd))
                offs >>= 1;

        /* Set ALE and clear CLE to start address cycle */
        /* Column address */
        hwctrl(mtd, offs & 0xff,
                       NAND_CTRL_ALE | NAND_CTRL_CHANGE); /* A[7:0] */
        hwctrl(mtd, (offs >> 8) & 0xff, NAND_CTRL_ALE); /* A[11:9] */
        /* Row address */
        if (cmd != NAND_CMD_RNDOUT) {
                hwctrl(mtd, (page_addr & 0xff),
                       NAND_CTRL_ALE); /* A[19:12] */
                hwctrl(mtd, ((page_addr >> 8) & 0xff),
                       NAND_CTRL_ALE); /* A[27:20] */
#ifdef CONFIG_SYS_NAND_5_ADDR_CYCLE
                /* One more address cycle for devices > 128MiB */
                hwctrl(mtd, (page_addr >> 16) & 0x0f,
                       NAND_CTRL_ALE); /* A[31:28] */
#endif
        }

        hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);


        /*
         * Program and erase have their own busy handlers status, sequential
         * in and status need no delay.
         */
        switch (cmd) {
        case NAND_CMD_CACHEDPROG:
        case NAND_CMD_PAGEPROG:
        case NAND_CMD_ERASE1:
        case NAND_CMD_ERASE2:
        case NAND_CMD_SEQIN:
        case NAND_CMD_RNDIN:
        case NAND_CMD_STATUS:
                return 0;

        case NAND_CMD_RNDOUT:
                /* No ready / busy check necessary */
                hwctrl(mtd, NAND_CMD_RNDOUTSTART, NAND_CTRL_CLE |
                       NAND_CTRL_CHANGE);
                hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
                return 0;

        case NAND_CMD_READ0:
                /* Latch in address */
                hwctrl(mtd, NAND_CMD_READSTART,
                       NAND_CTRL_CLE | NAND_CTRL_CHANGE);
                hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
        }

        /*
         * Apply this short delay always to ensure that we do wait tWB in
         * any case on any machine.
         */
        ndelay(150);

        while (!this->dev_ready(mtd))
                ;

        return 0;
}

static int nand_is_bad_block(int block)
{
        struct nand_chip *this = mtd_to_nand(mtd);

        nand_command(block, 0, CONFIG_SYS_NAND_BAD_BLOCK_POS,
                NAND_CMD_READOOB);

        /*
         * Read one byte (or two if it's a 16 bit chip).
         */
        if (this->options & NAND_BUSWIDTH_16) {
                if (readw(this->IO_ADDR_R) != 0xffff)
                        return 1;
        } else {
                if (readb(this->IO_ADDR_R) != 0xff)
                        return 1;
        }

        return 0;
}

static int nand_read_page(int block, int page, void *dst)
{
        struct nand_chip *this = mtd_to_nand(mtd);
        u_char ecc_calc[ECCTOTAL];
        u_char ecc_code[ECCTOTAL];
        u_char oob_data[CONFIG_SYS_NAND_OOBSIZE];
        int i;
        int eccsize = CONFIG_SYS_NAND_ECCSIZE;
        int eccbytes = CONFIG_SYS_NAND_ECCBYTES;
        int eccsteps = ECCSTEPS;
        uint8_t *p = dst;
        uint32_t data_pos = 0;
        uint8_t *oob = &oob_data[0] + nand_ecc_pos[0];
        uint32_t oob_pos = eccsize * eccsteps + nand_ecc_pos[0];

        nand_command(block, page, 0, NAND_CMD_READ0);

        for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
                this->ecc.hwctl(mtd, NAND_ECC_READ);
                nand_command(block, page, data_pos, NAND_CMD_RNDOUT);

                this->read_buf(mtd, p, eccsize);

                nand_command(block, page, oob_pos, NAND_CMD_RNDOUT);

                this->read_buf(mtd, oob, eccbytes);
                this->ecc.calculate(mtd, p, &ecc_calc[i]);

                data_pos += eccsize;
                oob_pos += eccbytes;
                oob += eccbytes;
        }

        /* Pick the ECC bytes out of the oob data */
        for (i = 0; i < ECCTOTAL; i++)
                ecc_code[i] = oob_data[nand_ecc_pos[i]];

        eccsteps = ECCSTEPS;
        p = dst;

        for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
                /* No chance to do something with the possible error message
                 * from correct_data(). We just hope that all possible errors
                 * are corrected by this routine.
                 */
                this->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
        }

        return 0;
}

/* nand_init() - initialize data to make nand usable by SPL */
void nand_init(void)
{
        /*
         * Init board specific nand support
         */
        mtd = nand_to_mtd(&nand_chip);
        nand_chip.IO_ADDR_R = nand_chip.IO_ADDR_W =
                (void  __iomem *)CONFIG_SYS_NAND_BASE;
        board_nand_init(&nand_chip);

        if (nand_chip.select_chip)
                nand_chip.select_chip(mtd, 0);

        /* NAND chip may require reset after power-on */
        nand_command(0, 0, 0, NAND_CMD_RESET);
}

/* Unselect after operation */
void nand_deselect(void)
{
        if (nand_chip.select_chip)
                nand_chip.select_chip(mtd, -1);
}

#include "nand_spl_loaders.c"