IPI_DOORBELL_NR
for (irq_hw_number_t i = 0; i < IPI_DOORBELL_NR; i++) {
mpic->ipi_domain = irq_domain_create_linear(of_fwnode_handle(node), IPI_DOORBELL_NR,
base_ipi = irq_domain_alloc_irqs(mpic->ipi_domain, IPI_DOORBELL_NR, NUMA_NO_NODE, NULL);
set_smp_ipi_range(base_ipi, IPI_DOORBELL_NR);
for_each_set_bit(i, &cause, IPI_DOORBELL_NR)