+int __init io_apic_get_redir_entries (int ioapic)
+{
+ union IO_APIC_reg_01 reg_01;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ioapic_lock, flags);
+ reg_01.raw = io_apic_read(ioapic, 1);
+ spin_unlock_irqrestore(&ioapic_lock, flags);
+
+ return reg_01.bits.entries;
+}
+
+int __init probe_nr_irqs(void)
+{
+ int idx;
+ int nr = 0;
+
+ for (idx = 0; idx < nr_ioapics; idx++)
+ nr += io_apic_get_redir_entries(idx);
+
+ /* double it for hotplug and msi and nmi */
+ nr <<= 1;
+
+ /* something wrong ? */
+ if (nr < 32)
+ nr = 32;
+
+ return nr;
+}
+