Archipelago » qemu

static lsi_request *lsi_find_by_tag(LSIState *s, uint32_t tag)

            return p;

    return NULL;

}

/* Record that data is available for a queued command.  Returns zero if

   the device was reselected, nonzero if the IO is deferred.  */

static int lsi_queue_tag(LSIState *s, uint32_t tag, uint32_t arg)

{

    lsi_request *p;

    p = lsi_find_by_tag(s, tag);

    if (!p) {

        BADF("IO with unknown tag %d\n", tag);

        return 1;

    }

    if (p->pending) {

        BADF("Multiple IO pending for tag %d\n", tag);

    }

    p->pending = arg;

    /* Reselect if waiting for it, or if reselection triggers an IRQ

       and the bus is free.

       Since no interrupt stacking is implemented in the emulation, it

       is also required that there are no pending interrupts waiting

       for service from the device driver. */

    if (s->waiting == 1 ||

        (lsi_irq_on_rsl(s) && !(s->scntl1 & LSI_SCNTL1_CON) &&

         !(s->istat0 & (LSI_ISTAT0_SIP | LSI_ISTAT0_DIP)))) {

        /* Reselect device.  */

        lsi_reselect(s, p);

        return 0;

    } else {

        DPRINTF("Queueing IO tag=0x%x\n", tag);

        p->pending = arg;

        return 1;

    }