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=1641Acked-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

A -mm patch caused:

In file included from drivers/pci/quirks.c:532:
include/asm/io_apic.h:61: error: "MAX_IO_APICS" undeclared here (not in a function)

So let's include the needed header.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On the Unisys ES7000/ONE system, we encountered a problem where performing
a kexec reboot or dump on any cell other than cell 0 causes the system
timer to stop working, resulting in a hang during timer calibration in the
new kernel.

We traced the problem to one line of code in disable_IO_APIC(), which needs
to restore the timer's IO-APIC configuration before rebooting.  The code is
currently using the 4-bit physical destination field, rather than using the
8-bit logical destination field, and it cuts off the upper 4 bits of the
timer's APIC ID.  If we change this to use the logical destination field,
the timer works and we can kexec on the upper cells.  This was tested on
two different cells (0 and 2) in an ES7000/ONE system.

For reference, the relevant Intel xAPIC spec is kept at
ftp://download.intel.com/design/chipsets/e8501/datashts/30962001.pdf,
specifically on page 334.
Signed-off-by: NBenjamin M Romer <benjamin.romer@unisys.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

This is just commit 130fe05d ported to
x86-64, for all the same reasons.  It cleans up the IO-APIC accesses in
order to then fix the ordering issues.

We move the accessor functions (that were only used by io_apic.c) out of
a header file, and use proper memory-mapped accesses rather than making
up our own "volatile" pointers.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

With more irqs in the system we don't need this.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch removes the change in behavior of the irq allocation code when
CONFIG_PCI_MSI is defined.  Removing all instances of the assumption that irq
== vector.

create_irq is rewritten to first allocate a free irq and then to assign that
irq a vector.

assign_irq_vector is made static and the AUTO_ASSIGN case which allocates an
vector not bound to an irq is removed.

The ioapic vector methods are removed, and everything now works with irqs.

The definition of NR_IRQS no longer depends on CONFIG_PCI_MSI

[akpm@osdl.org: cleanup]
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch removes the change in behavior of the irq allocation code when
CONFIG_PCI_MSI is defined.  Removing all instances of the assumption that irq
== vector.

create_irq is rewritten to first allocate a free irq and then to assign that
irq a vector.

assign_irq_vector is made static and the AUTO_ASSIGN case which allocates an
vector not bound to an irq is removed.

The ioapic vector methods are removed, and everything now works with irqs.

The definition of NR_IRQS no longer depends on CONFIG_PCI_MSI
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

IO-APIC or local APIC can only be disabled at runtime anyways and
Kconfig has forced these options on for a long time now.

The Kconfigs are kept only now for the benefit of the shared acpi
boot.c code.
Signed-off-by: NAndi Kleen <ak@suse.de>

The patch addresses a problem with ACPI SCI interrupt entry, which gets
re-used, and the IRQ is assigned to another unrelated device.  The patch
corrects the code such that SCI IRQ is skipped and duplicate entry is
avoided.  Second issue came up with VIA chipset, the problem was caused by
original patch assigning IRQs starting 16 and up.  The VIA chipset uses
4-bit IRQ register for internal interrupt routing, and therefore cannot
handle IRQ numbers assigned to its devices.  The patch corrects this
problem by allowing PCI IRQs below 16.

Cc: len.brown@intel.com

Signed-off by: Natalie Protasevich <Natalie.Protasevich@unisys.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

it has been a synonym for CONFIG_ACPI since 2.6.12
Signed-off-by: NLen Brown <len.brown@intel.com>

Introduce proper declarations for i8253_lock and i8259A_lock.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It is unnecessary on modern Intel or AMD systems, and that is all we support
on x86-64

Also causes problems on various systems
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!