x86: find nr_irqs_gsi with mp_ioapic_routing
Impact: find right nr_irqs_gsi on some systems.
One test-system has gap between gsi's:
[ 0.000000] ACPI: IOAPIC (id[0x04] address[0xfec00000] gsi_base[0])
[ 0.000000] IOAPIC[0]: apic_id 4, version 0, address 0xfec00000, GSI 0-23
[ 0.000000] ACPI: IOAPIC (id[0x05] address[0xfeafd000] gsi_base[48])
[ 0.000000] IOAPIC[1]: apic_id 5, version 0, address 0xfeafd000, GSI 48-54
[ 0.000000] ACPI: IOAPIC (id[0x06] address[0xfeafc000] gsi_base[56])
[ 0.000000] IOAPIC[2]: apic_id 6, version 0, address 0xfeafc000, GSI 56-62
...
[ 0.000000] nr_irqs_gsi: 38
So nr_irqs_gsi is not right. some irq for MSI will overwrite with io_apic.
need to get that with acpi_probe_gsi when acpi io_apic is used
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 3efa996..c334fe7 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -961,6 +961,29 @@
nr_ioapics++;
}
+int __init acpi_probe_gsi(void)
+{
+ int idx;
+ int gsi;
+ int max_gsi = 0;
+
+ if (acpi_disabled)
+ return 0;
+
+ if (!acpi_ioapic)
+ return 0;
+
+ max_gsi = 0;
+ for (idx = 0; idx < nr_ioapics; idx++) {
+ gsi = mp_ioapic_routing[idx].gsi_end;
+
+ if (gsi > max_gsi)
+ max_gsi = gsi;
+ }
+
+ return max_gsi + 1;
+}
+
static void assign_to_mp_irq(struct mpc_intsrc *m,
struct mpc_intsrc *mp_irq)
{