set_eecd(E1000State *s, int index, uint32_t val)
{
    uint32_t oldval = s->eecd_state.old_eecd;

    s->eecd_state.old_eecd = val & (E1000_EECD_SK | E1000_EECD_CS |
            E1000_EECD_DI|E1000_EECD_FWE_MASK|E1000_EECD_REQ);
    if (!(E1000_EECD_CS & val)) {            /* CS inactive; nothing to do */
        return;
    }
    if (E1000_EECD_CS & (val ^ oldval)) {    /* CS rise edge; reset state */
        s->eecd_state.val_in = 0;
        s->eecd_state.bitnum_in = 0;
        s->eecd_state.bitnum_out = 0;
        s->eecd_state.reading = 0;
    }
    if (!(E1000_EECD_SK & (val ^ oldval))) {    /* no clock edge */
        return;
    }
    if (!(E1000_EECD_SK & val)) {               /* falling edge */
        s->eecd_state.bitnum_out++;
        return;
    }
    s->eecd_state.val_in <<= 1;
    if (val & E1000_EECD_DI)
        s->eecd_state.val_in |= 1;
    if (++s->eecd_state.bitnum_in == 9 && !s->eecd_state.reading) {
        s->eecd_state.bitnum_out = ((s->eecd_state.val_in & 0x3f)<<4)-1;
        s->eecd_state.reading = (((s->eecd_state.val_in >> 6) & 7) ==
            EEPROM_READ_OPCODE_MICROWIRE);
    }
    DBGOUT(EEPROM, "eeprom bitnum in %d out %d, reading %d\n",
           s->eecd_state.bitnum_in, s->eecd_state.bitnum_out,
           s->eecd_state.reading);
}
set_eecd(E1000State *s, int index, uint32_t val)
{
    uint32_t oldval = s->eecd_state.old_eecd;

    s->eecd_state.old_eecd = val & (E1000_EECD_SK | E1000_EECD_CS |
            E1000_EECD_DI|E1000_EECD_FWE_MASK|E1000_EECD_REQ);
    if (!(E1000_EECD_CS & val)) {             
        return;
    }
    if (E1000_EECD_CS & (val ^ oldval)) {     
        s->eecd_state.val_in = 0;
        s->eecd_state.bitnum_in = 0;
        s->eecd_state.bitnum_out = 0;
        s->eecd_state.reading = 0;
    }
    if (!(E1000_EECD_SK & (val ^ oldval))) {     
        return;
    }
    if (!(E1000_EECD_SK & val)) {                
        s->eecd_state.bitnum_out++;
        return;
    }
    s->eecd_state.val_in <<= 1;
    if (val & E1000_EECD_DI)
        s->eecd_state.val_in |= 1;
    if (++s->eecd_state.bitnum_in == 9 && !s->eecd_state.reading) {
        s->eecd_state.bitnum_out = ((s->eecd_state.val_in & 0x3f)<<4)-1;
        s->eecd_state.reading = (((s->eecd_state.val_in >> 6) & 7) ==
            EEPROM_READ_OPCODE_MICROWIRE);
    }
    DBGOUT(EEPROM, "eeprom bitnum in %d out %d, reading %d\n",
           s->eecd_state.bitnum_in, s->eecd_state.bitnum_out,
           s->eecd_state.reading);
}