uint32_t ps2_read_data(void *opaque)
{
PS2State *s = (PS2State *)opaque;
PS2Queue *q;
int val, index;
trace_ps2_read_data(opaque);
q = &s->queue;
if (q->count == 0) {
/* NOTE: if no data left, we return the last keyboard one
(needed for EMM386) */
/* XXX: need a timer to do things correctly */
index = q->rptr - 1;
if (index < 0)
index = PS2_QUEUE_SIZE - 1;
val = q->data[index];
} else {
val = q->data[q->rptr];
if (++q->rptr == PS2_QUEUE_SIZE)
q->rptr = 0;
q->count--;
/* reading deasserts IRQ */
s->update_irq(s->update_arg, 0);
/* reassert IRQs if data left */
s->update_irq(s->update_arg, q->count != 0);
}
return val;
}
void ps2_queue(void *opaque, int b)
{
PS2State *s = (PS2State *)opaque;
PS2Queue *q = &s->queue;
if (q->count >= PS2_QUEUE_SIZE - 1)
return;
q->data[q->wptr] = b;
if (++q->wptr == PS2_QUEUE_SIZE)
q->wptr = 0;
q->count++;
s->update_irq(s->update_arg, 1);
}
void ps2_queue(void *opaque, int b)
{
PS2State *s = (PS2State *)opaque;
PS2Queue *q = &s->queue;
if (q->count >= PS2_QUEUE_SIZE)
return;
q->data[q->wptr] = b;
#ifdef CONFIG_TCG_TAINT
q->taint_data[q->wptr] = 0;
#endif /* CONFIG_TCG_TAINT */
if (++q->wptr == PS2_QUEUE_SIZE)
q->wptr = 0;
q->count++;
s->update_irq(s->update_arg, 1);
}
