/* $NetBSD: i28f128.c,v 1.4 2005/12/11 12:17:34 christos Exp $ */

/*
 * Copyright (c) 2003 Naoto Shimazaki.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY NAOTO SHIMAZAKI AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE NAOTO OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Flash Memory Writer
 */
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: i28f128.c,v 1.4 2005/12/11 12:17:34 christos Exp $");

#include <lib/libsa/stand.h>

#include "extern.h"

#include "i28f128reg.h"

#define USE_TWIDDLE

/*
 * XXX
 * this function is too much specific for the device.
 */
int
i28f128_probe(void *base)
{
        static const u_int8_t   vendor_code[] = {
                0x89,   /* manufacturer code:   intel */
                0x18,   /* device code:         28F128 */
        };

        static const u_int8_t   idstr[] = {
                'Q', 'R', 'Y',
                0x01, 0x00,
                0x31, 0x00,
                0xff
        };

        int     i;

        /* start Common Flash Interface Query */
        REGWRITE_2(base, 0, 0x98);

        /* read CFI Query ID string */
        for (i = 0; idstr[i] != 0xff; i++) {
                if (REGREAD_2(base, (0x10 + i) << 1) != idstr[i])
                        return 1;
        }

        /* read manufacturer code and device code */
        if (REGREAD_2(base, 0x00) != vendor_code[0])
                return 1;
        if (REGREAD_2(base, 0x02) != vendor_code[1])
                return 1;
        
        REGWRITE_2(base, 0, 0xff);
        return 0;
}

static int
block_erase(void *addr)
{
        int     status;

        REGWRITE_2(addr, 0, I28F128_BLK_ERASE_1ST);
        REGWRITE_2(addr, 0, I28F128_BLK_ERASE_2ND);

        do {
                status = REGREAD_2(addr, 0);
        } while (!ISSET(status, I28F128_S_READY));

        REGWRITE_2(addr, 0, I28F128_CLEAR_STATUS);
        REGWRITE_2(addr, 0, I28F128_RESET);

        return status & (I28F128_S_ERASE_SUSPEND
                         | I28F128_S_ERASE_ERROR
                         | I28F128_S_BLOCK_LOCKED);
}

static int
word_program(void *addr, u_int16_t data)
{
        int     status;

        REGWRITE_2(addr, 0, I28F128_WORDBYTE_PROG);
        REGWRITE_2(addr, 0, data);
        
        do {
                status = REGREAD_2(addr, 0);
        } while (!ISSET(status, I28F128_S_READY));

        REGWRITE_2(addr, 0, I28F128_CLEAR_STATUS);
        REGWRITE_2(addr, 0, I28F128_RESET);

        return status & (I28F128_S_PROG_ERROR
                         | I28F128_S_LOW_VOLTAGE
                         | I28F128_S_PROG_SUSPEND
                         | I28F128_S_BLOCK_LOCKED);
}

static int
block_write(void *dst, const void *src)
{
        int             status;
        const u_int16_t *p;
        u_int16_t       *q;
        const u_int16_t *fence;
        int             i;
        const int       wbuf_count = I28F128_WBUF_SIZE >> 1;

        /* dst must be aligned to block boundary. */
        if (I28F128_BLOCK_MASK & (u_int32_t) dst)
                return -1;

        if (memcmp(dst, src, I28F128_BLOCK_SIZE) == 0)
                return 0;

        if ((status = block_erase(dst)) != 0)
                return status;

        p = src;
        q = dst;
        fence = p + (I28F128_BLOCK_SIZE >> 1);
        do {
                do {
                        REGWRITE_2(dst, 0, I28F128_WRITE_BUFFER);
                        status = REGREAD_2(dst, 0);
                } while (!ISSET(status, I28F128_XS_BUF_AVAIL));

                REGWRITE_2(dst, 0, wbuf_count - 1);

                for (i = wbuf_count; i > 0; i--, p++, q++)
                        REGWRITE_2(q, 0, *p);

                REGWRITE_2(dst, 0, I28F128_WBUF_CONFIRM);

                do {
                        REGWRITE_2(dst, 0, I28F128_READ_STATUS);
                        status = REGREAD_2(dst, 0);
                } while (!(status & I28F128_S_READY));

        } while (p < fence);

        REGWRITE_2(dst, 0, I28F128_CLEAR_STATUS);
        REGWRITE_2(dst, 0, I28F128_RESET);

        return 0;
}

int
i28f128_region_write(void *dst, const void *src, size_t len)
{
        int             status;
        const u_int16_t *p = src;
        u_int16_t       *q = dst;

        /* dst must be aligned to block boundary. */
        if (I28F128_BLOCK_MASK & (u_int32_t) dst)
                return -1;

        while (len >= I28F128_BLOCK_SIZE) {
                if ((status = block_write(q, p)) != 0)
                        return status;
                putchar('b');
                p += I28F128_BLOCK_SIZE >> 1;
                q += I28F128_BLOCK_SIZE >> 1;
                len -= I28F128_BLOCK_SIZE;
        }

        if (len > 0) {
                if (memcmp(p, q, len) == 0)
                        return 0;
                if ((status = block_erase(q)) != 0)
                        return status;
                for (; len > 0; len -= 2) {
#ifdef USE_TWIDDLE
                        if (((u_int32_t) q % 4096) == 0)
                                twiddle();
#endif
                        if ((status = word_program(q++, *p++)) != 0)
                                return status;
                }
                printf("w");
        }

        putchar('\n');
        return 0;
}