- /* Check if there's already an IRQ assigned to the timer */
- if (hdp->hd_irq[i]) {
- hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
- continue;
- }
-
- hpet_config = readq(&timer->hpet_config);
- irq_bitmap = (hpet_config & Tn_INT_ROUTE_CAP_MASK)
- >> Tn_INT_ROUTE_CAP_SHIFT;
- if (!irq_bitmap)
- irq = 0; /* No valid IRQ Assignable */
- else {
- irq = find_first_bit(&irq_bitmap, 32);
- do {
- hpet_config |= irq << Tn_INT_ROUTE_CNF_SHIFT;
- writeq(hpet_config, &timer->hpet_config);
-
- /*
- * Verify whether we have written a valid
- * IRQ number by reading it back again
- */
- hpet_config = readq(&timer->hpet_config);
- if (irq == (hpet_config & Tn_INT_ROUTE_CNF_MASK)
- >> Tn_INT_ROUTE_CNF_SHIFT)
- break; /* Success */
- } while ((irq = (find_next_bit(&irq_bitmap, 32, irq))));
- }
- hpetp->hp_dev[i].hd_hdwirq = irq;
- }