/*
 * Copyright 1998-2001 by Donald Becker.
 * This software may be used and distributed according to the terms of
 * the GNU General Public License (GPL), incorporated herein by reference.
 * Contact the author for use under other terms.
 *
 * This program must be compiled with "-O"!
 * See the bottom of this file for the suggested compile-command.
 *
 * The author may be reached as becker@scyld.com, or C/O
 *  Scyld Computing Corporation
 *  410 Severn Ave., Suite 210
 *  Annapolis MD 21403
 *
 * Common-sense licensing statement: Using any portion of this program in
 * your own program means that you must give credit to the original author
 * and release the resulting code under the GPL.
 */

/* avoid unnecessary memcpy function */
#define _PPC_STRING_H_

#include <common.h>
#include <exports.h>

static int reset_eeprom(unsigned long ioaddr, unsigned char *hwaddr);

int eepro100_eeprom(int argc, char * const argv[])
{
        int ret = 0;

        unsigned char hwaddr1[6] = { 0x00, 0x00, 0x02, 0x03, 0x04, 0x05 };
        unsigned char hwaddr2[6] = { 0x00, 0x00, 0x02, 0x03, 0x04, 0x06 };

        app_startup(argv);

#if defined(CONFIG_OXC)
        ret |= reset_eeprom(0x80000000, hwaddr1);
        ret |= reset_eeprom(0x81000000, hwaddr2);
#endif

        return ret;
}

/* Default EEPROM for i82559 */
static unsigned short default_eeprom[64] = {
        0x0100, 0x0302, 0x0504, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
        0xffff, 0xffff, 0x40c0, 0x0000, 0x0000, 0xffff, 0xffff, 0xffff,
        0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
        0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
        0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
        0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
        0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
        0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff
};

static unsigned short eeprom[256];

static int eeprom_size = 64;
static int eeprom_addr_size = 6;

static int debug = 0;

static inline unsigned short swap16(unsigned short x)
{
        return (((x & 0xff) << 8) | ((x & 0xff00) >> 8));
}

static inline void outw(short data, long addr)
{
        *(volatile short *)(addr) = swap16(data);
}

static inline short inw(long addr)
{
        return swap16(*(volatile short *)(addr));
}

void *memcpy(void *dst, const void *src, unsigned int len)
{
        char *ret = dst;
        while (len-- > 0) {
                *ret++ = *((char *)src);
                src++;
        }
        return (void *)ret;
}

/* The EEPROM commands include the alway-set leading bit. */
#define EE_WRITE_CMD    (5)
#define EE_READ_CMD             (6)
#define EE_ERASE_CMD    (7)

/* Serial EEPROM section. */
#define EE_SHIFT_CLK    0x01    /* EEPROM shift clock. */
#define EE_CS                   0x02    /* EEPROM chip select. */
#define EE_DATA_WRITE   0x04    /* EEPROM chip data in. */
#define EE_DATA_READ    0x08    /* EEPROM chip data out. */
#define EE_ENB                  (0x4800 | EE_CS)
#define EE_WRITE_0              0x4802
#define EE_WRITE_1              0x4806
#define EE_OFFSET               14

/* Delay between EEPROM clock transitions. */
#define eeprom_delay(ee_addr)   inw(ee_addr)

/* Wait for the EEPROM to finish the previous operation. */
static int eeprom_busy_poll(long ee_ioaddr)
{
        int i;
        outw(EE_ENB, ee_ioaddr);
        for (i = 0; i < 10000; i++)                     /* Typical 2000 ticks */
                if (inw(ee_ioaddr) & EE_DATA_READ)
                        break;
        return i;
}

/* This executes a generic EEPROM command, typically a write or write enable.
   It returns the data output from the EEPROM, and thus may also be used for
   reads. */
static int do_eeprom_cmd(long ioaddr, int cmd, int cmd_len)
{
        unsigned retval = 0;
        long ee_addr = ioaddr + EE_OFFSET;

        if (debug > 1)
                printf(" EEPROM op 0x%x: ", cmd);

        outw(EE_ENB | EE_SHIFT_CLK, ee_addr);

        /* Shift the command bits out. */
        do {
                short dataval = (cmd & (1 << cmd_len)) ? EE_WRITE_1 : EE_WRITE_0;
                outw(dataval, ee_addr);
                eeprom_delay(ee_addr);
                if (debug > 2)
                        printf("%X", inw(ee_addr) & 15);
                outw(dataval | EE_SHIFT_CLK, ee_addr);
                eeprom_delay(ee_addr);
                retval = (retval << 1) | ((inw(ee_addr) & EE_DATA_READ) ? 1 : 0);
        } while (--cmd_len >= 0);
#if 0
        outw(EE_ENB, ee_addr);
#endif
        /* Terminate the EEPROM access. */
        outw(EE_ENB & ~EE_CS, ee_addr);
        if (debug > 1)
                printf(" EEPROM result is 0x%5.5x.\n", retval);
        return retval;
}

static int read_eeprom(long ioaddr, int location, int addr_len)
{
        return do_eeprom_cmd(ioaddr, ((EE_READ_CMD << addr_len) | location)
                << 16 , 3 + addr_len + 16) & 0xffff;
}

static void write_eeprom(long ioaddr, int index, int value, int addr_len)
{
        long ee_ioaddr = ioaddr + EE_OFFSET;
        int i;

        /* Poll for previous op finished. */
        eeprom_busy_poll(ee_ioaddr);                    /* Typical 0 ticks */
        /* Enable programming modes. */
        do_eeprom_cmd(ioaddr, (0x4f << (addr_len-4)), 3 + addr_len);
        /* Do the actual write. */
        do_eeprom_cmd(ioaddr,
                                  (((EE_WRITE_CMD<<addr_len) | index)<<16) | (value & 0xffff),
                                  3 + addr_len + 16);
        /* Poll for write finished. */
        i = eeprom_busy_poll(ee_ioaddr);                        /* Typical 2000 ticks */
        if (debug)
                printf(" Write finished after %d ticks.\n", i);
        /* Disable programming. This command is not instantaneous, so we check
           for busy before the next op. */
        do_eeprom_cmd(ioaddr, (0x40 << (addr_len-4)), 3 + addr_len);
        eeprom_busy_poll(ee_ioaddr);
}

static int reset_eeprom(unsigned long ioaddr, unsigned char *hwaddr)
{
        unsigned short checksum = 0;
        int size_test;
        int i;

        printf("Resetting i82559 EEPROM @ 0x%08lX ... ", ioaddr);

        size_test = do_eeprom_cmd(ioaddr, (EE_READ_CMD << 8) << 16, 27);
        eeprom_addr_size = (size_test & 0xffe0000) == 0xffe0000 ? 8 : 6;
        eeprom_size = 1 << eeprom_addr_size;

        memcpy(eeprom, default_eeprom, sizeof default_eeprom);

        for (i = 0; i < 3; i++)
                eeprom[i] = (hwaddr[i*2+1]<<8) + hwaddr[i*2];

        /* Recalculate the checksum. */
        for (i = 0; i < eeprom_size - 1; i++)
                checksum += eeprom[i];
        eeprom[i] = 0xBABA - checksum;

        for (i = 0; i < eeprom_size; i++)
                write_eeprom(ioaddr, i, eeprom[i], eeprom_addr_size);

        for (i = 0; i < eeprom_size; i++)
                if (read_eeprom(ioaddr, i, eeprom_addr_size) != eeprom[i]) {
                        printf("failed\n");
                        return 1;
                }

        printf("done\n");
        return 0;
}