ACPI: boot correctly with "nosmp" or "maxcpus=0"
In MPS mode, "nosmp" and "maxcpus=0" boot a UP kernel with IOAPIC disabled.
However, in ACPI mode, these parameters didn't completely disable
the IO APIC initialization code and boot failed.
init/main.c:
Disable the IO_APIC if "nosmp" or "maxcpus=0"
undefine disable_ioapic_setup() when it doesn't apply.
i386:
delete ioapic_setup(), it was a duplicate of parse_noapic()
delete undefinition of disable_ioapic_setup()
x86_64:
rename disable_ioapic_setup() to parse_noapic() to match i386
define disable_ioapic_setup() in header to match i386
http://bugzilla.kernel.org/show_bug.cgi?id=1641
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/asm-x86_64/io_apic.h b/include/asm-x86_64/io_apic.h
index 969d225..d9f2e54 100644
--- a/include/asm-x86_64/io_apic.h
+++ b/include/asm-x86_64/io_apic.h
@@ -109,6 +109,12 @@
/* 1 if "noapic" boot option passed */
extern int skip_ioapic_setup;
+static inline void disable_ioapic_setup(void)
+{
+ skip_ioapic_setup = 1;
+}
+
+
/*
* If we use the IO-APIC for IRQ routing, disable automatic
* assignment of PCI IRQ's.