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We need to fall back from logical-flat APIC mode to physical-flat mode
when we have more than 8 CPUs.  However, in the presence of CPU
hotplug(with bios listing not enabled but possible cpus as disabled cpus in
MADT), we have to consider the number of possible CPUs rather than
the number of current CPUs; otherwise we may cross the 8-CPU boundary
when CPUs are added later.

32bit apic code can use more cleanups (like the removal of vendor checks in
32bit default_setup_apic_routing()) and more unifications with 64bit code.
Yinghai has some patches in works already. This patch addresses the boot issue
that is reported in the virtualization guest context.

[ hpa: incorporated function annotation feedback from Yinghai Lu ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1265767304.2833.19.camel@sbs-t61.sc.intel.com>
Acked-by: Shaohui Zheng <shaohui.zheng@intel.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

cleanup only.

setup_arch(), doesn't care care if ACPI initialization succeeded
or failed, so delete acpi_boot_table_init()'s return value.
Signed-off-by: Len Brown <len.brown@intel.com>

That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Some IO-APIC routines are ACPI specific now, but need to
be exposed when CONFIG_ACPI=n for the benefit of SFI.

Remove #ifdef ACPI around these routines:

io_apic_get_unique_id(int ioapic, int apic_id);
io_apic_get_version(int ioapic);
io_apic_get_redir_entries(int ioapic);

Move these routines from ACPI-specific boot.c to io_apic.c:

uniq_ioapic_id(u8 id)
mp_find_ioapic()
mp_find_ioapic_pin()
mp_register_ioapic()

Also, since uniq_ioapic_id() is now no longer static,
re-name it to io_apic_unique_id() for consistency
with the other public io_apic routines.

For simplicity, do not #ifdef the resulting code ACPI || SFI,
thought that could be done in the future if it is important
to optimize the !ACPI !SFI IO-APIC x86 kernel for size.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: x86@kernel.org

x86 arch support for remapping HPET MSI's by associating the HPET timer block
with the interrupt-remapping HW unit and setting up appropriate irq_chip
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Jay Fenlason <fenlason@redhat.com>
LKML-Reference: <20090804190729.630510000@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

We don't put braces around a single statement.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

Move
arch/x86/kernel/acpi/boot.c: acpi_parse_mcfg()
to
arch/x86/pci/mmconfig-shared.c: pci_parse_mcfg()
where it is used, and make it static.

Move associated globals and helper routine with it.

No functional change.

This code move is in preparation for SFI support,
which will allow the PCI code to find the MCFG table
on systems which do not support ACPI.
Signed-off-by: Len Brown <len.brown@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>

See http://marc.info/?l=linux-acpi&m=124068823904429&w=2 for discussion
Signed-off-by: Olivier Berger <oberger@ouvaton.org>
Signed-off-by: Len Brown <len.brown@intel.com>

Testing CONFIG_ACPI inside boot.c is a waste of text,
since boot.c is built only when CONFIG_ACPI=y
Signed-off-by: Len Brown <len.brown@intel.com>

Fix the fact that the IOAPIC version number in the x86_64 code path always
gets assigned to 0, instead of the correct value.

Before the patch: (from "dmesg" output):

 ACPI: IOAPIC (id[0x08] address[0xfec00000] gsi_base[0])
 IOAPIC[0]: apic_id 8, version 0, address 0xfec00000, GSI 0-23     <---

 After the patch:
 ACPI: IOAPIC (id[0x08] address[0xfec00000] gsi_base[0])
 IOAPIC[0]: apic_id 8, version 32, address 0xfec00000, GSI 0-23    <---

History:

io_apic_get_version() was compiled out of the x86_64 code path in the commit
f2c2cca3:

Author: Andi Kleen <ak@suse.de>
Date:   Tue Sep 26 10:52:37 2006 +0200

    [PATCH] Remove APIC version/cpu capability mpparse checking/printing

    ACPI went to great trouble to get the APIC version and CPU capabilities
    of different CPUs before passing them to the mpparser. But all
    that data was used was to print it out.  Actually it even faked some data
    based on the boot cpu, not on the actual CPU being booted.

    Remove all this code because it's not needed.

    Cc: len.brown@intel.com

At the time, the IOAPIC version number was deliberately not printed
in the x86_64 code path. However, after the x86 and x86_64 files were
merged, the net result is that the IOAPIC version is printed incorrectly
in the x86_64 code path.

The patch below provides a fix. I have tested it with acpi, and with
acpi=off, and did not see any problems.
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Acked-by: Yinghai Lu <yhlu.kernel@gmail.com>
LKML-Reference: <20090416014230.4885.94926.sendpatchset@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
*************************

Len expressed concern that the update_mptable feature has
side-effects on the ACPI code.

Make it sure explicitly that the code only ever gets called if
the (default disabled) update_mptable boot quirk option is
disabled.

[ Impact: isolate the update_mptable feature from ACPI code more ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A0DC832.5090200@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

according to Ingo, io_apic irq-setup related functions have too many
parameters with a repetitive signature.

So reduce related funcs to get less params by passing a pointer
to a newly defined io_apic_irq_attr structure.

v2: io_apic_irq ==> irq_attr
    triggering ==> trigger

v3: add set_io_apic_irq_attr

[ Impact: cleanup ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A08ACD3.2070401@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Prepare to call setup_io_apic_routing() in pcibios_irq_enable()
also remove not needed member apic_id.

[ Impact: clean up, prepare for future change ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C3DD.3050104@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The patch to call mp_config_acpi_gsi() from the ACPI IRQ registration
code never got mainline because there were open discussions about it.

This call is needed to properly update the kernel's copy of the mptable,
when the update_mptable boot parameter is needed.

Now that the dust has settled with the APIC unification, and since there
were no objections when the patch was re-submitted, try this again.

[ Impact: fix the update_mptable boot parameter ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C387.7090103@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

We already have a per cpu vector on 32-bit via recent changes, and
don't need this trick any more (which trick obfuscates the real GSI
mappings and which only triggers on larger systems to begin with):

On 3 ioapic system (24 per ioapic) before patch I got:

ACPI: PCI Interrupt Link [ILSB] enabled at IRQ 71
IOAPIC[2]: Set routing entry (10-23 -> 0xa9 -> IRQ 64 Mode:1 Active:1)
pci 0000:80:01.1: PCI INT A -> Link[ILSB] -> GSI 71 (level, low) -> IRQ 64
ACPI: PCI Interrupt Link [LE5B] enabled at IRQ 67
IOAPIC[2]: Set routing entry (10-19 -> 0xb1 -> IRQ 65 Mode:1 Active:1)
pci 0000:83:00.0: PCI INT B -> Link[LE5B] -> GSI 67 (level, low) -> IRQ 65
ACPI: PCI Interrupt Link [LE5A] enabled at IRQ 66
IOAPIC[2]: Set routing entry (10-18 -> 0xb9 -> IRQ 66 Mode:1 Active:1)
pci 0000:83:00.1: PCI INT A -> Link[LE5A] -> GSI 66 (level, low) -> IRQ 66
ACPI: PCI Interrupt Link [LE5D] enabled at IRQ 65
IOAPIC[2]: Set routing entry (10-17 -> 0xc1 -> IRQ 67 Mode:1 Active:1)
pci 0000:84:00.0: PCI INT B -> Link[LE5D] -> GSI 65 (level, low) -> IRQ 67
ACPI: PCI Interrupt Link [LE5C] enabled at IRQ 64
IOAPIC[2]: Set routing entry (10-16 -> 0xc9 -> IRQ 68 Mode:1 Active:1)
pci 0000:84:00.1: PCI INT A -> Link[LE5C] -> GSI 64 (level, low) -> IRQ 68
pci 0000:87:00.0: PCI INT B -> Link[LE5A] -> GSI 66 (level, low) -> IRQ 66
pci 0000:87:00.1: PCI INT A -> Link[LE5D] -> GSI 65 (level, low) -> IRQ 67
pci 0000:88:00.0: PCI INT B -> Link[LE5C] -> GSI 64 (level, low) -> IRQ 68
pci 0000:88:00.1: PCI INT A -> Link[LE5B] -> GSI 67 (level, low) -> IRQ 65
pci 0000:8b:00.0: PCI INT B -> Link[LE5A] -> GSI 66 (level, low) -> IRQ 66
pci 0000:8b:00.1: PCI INT A -> Link[LE5D] -> GSI 65 (level, low) -> IRQ 67
pci 0000:8c:00.0: PCI INT B -> Link[LE5C] -> GSI 64 (level, low) -> IRQ 68
pci 0000:8c:00.1: PCI INT A -> Link[LE5B] -> GSI 67 (level, low) -> IRQ 65

after the patch we get:

ACPI: PCI Interrupt Link [ILSB] enabled at IRQ 71
IOAPIC[2]: Set routing entry (10-23 -> 0xa9 -> IRQ 71 Mode:1 Active:1)
pci 0000:80:01.1: PCI INT A -> Link[ILSB] -> GSI 71 (level, low) -> IRQ 71
ACPI: PCI Interrupt Link [LE5B] enabled at IRQ 67
IOAPIC[2]: Set routing entry (10-19 -> 0xb1 -> IRQ 67 Mode:1 Active:1)
pci 0000:83:00.0: PCI INT B -> Link[LE5B] -> GSI 67 (level, low) -> IRQ 67
ACPI: PCI Interrupt Link [LE5A] enabled at IRQ 66
IOAPIC[2]: Set routing entry (10-18 -> 0xb9 -> IRQ 66 Mode:1 Active:1)
pci 0000:83:00.1: PCI INT A -> Link[LE5A] -> GSI 66 (level, low) -> IRQ 66
ACPI: PCI Interrupt Link [LE5D] enabled at IRQ 65
IOAPIC[2]: Set routing entry (10-17 -> 0xc1 -> IRQ 65 Mode:1 Active:1)
pci 0000:84:00.0: PCI INT B -> Link[LE5D] -> GSI 65 (level, low) -> IRQ 65
ACPI: PCI Interrupt Link [LE5C] enabled at IRQ 64
IOAPIC[2]: Set routing entry (10-16 -> 0xc9 -> IRQ 64 Mode:1 Active:1)
pci 0000:84:00.1: PCI INT A -> Link[LE5C] -> GSI 64 (level, low) -> IRQ 64
pci 0000:87:00.0: PCI INT B -> Link[LE5A] -> GSI 66 (level, low) -> IRQ 66
pci 0000:87:00.1: PCI INT A -> Link[LE5D] -> GSI 65 (level, low) -> IRQ 65
pci 0000:88:00.0: PCI INT B -> Link[LE5C] -> GSI 64 (level, low) -> IRQ 64
pci 0000:88:00.1: PCI INT A -> Link[LE5B] -> GSI 67 (level, low) -> IRQ 67
pci 0000:8b:00.0: PCI INT B -> Link[LE5A] -> GSI 66 (level, low) -> IRQ 66
pci 0000:8b:00.1: PCI INT A -> Link[LE5D] -> GSI 65 (level, low) -> IRQ 65
pci 0000:8c:00.0: PCI INT B -> Link[LE5C] -> GSI 64 (level, low) -> IRQ 64
pci 0000:8c:00.1: PCI INT A -> Link[LE5B] -> GSI 67 (level, low) -> IRQ 67

As it can be seen that GSIs now get mapped lineary.

[ Impact: simplify irq number mapping on bigger 32-bit systems ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C35C.7060207@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

We want to use dev_to_node() later on, to be aware of the 'home node'
of the GSI in question.

[ Impact: cleanup, prepare the IRQ code to be more NUMA aware ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Len Brown <lenb@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Len Brown <lenb@kernel.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-acpi@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
LKML-Reference: <49F65560.20904@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

All logical processors with APIC ID values of 255 and greater will have their
APIC reported through Processor X2APIC structure (type-9 entry type) and all
logical processors with APIC ID less than 255 will have their APIC reported
through legacy Processor Local APIC (type-0 entry type) only. This is the
same case even for NMI structure reporting.
    
The Processor X2APIC Affinity structure provides the association between the
X2APIC ID of a logical processor and the proximity domain to which the logical
processor belongs.
    
For OSPM, Procssor IDs outside the 0-254 range are to be declared as Device()
objects in the ACPI namespace.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

update ACPI Development Discussion List
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Impact: cleanup
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: cleanup

Remove genapic.h and remove all references to it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Add mp_find_ioapic_pin() to find an IO APIC's specific pin from a GSI,
and use this function within acpi/boot.  Make it non-static so other
code can use it too.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

to prevent wrongly overwriting fixmap that still want to use.

ACPI used to rely on low mappings being all linearly mapped and
grew a habit: it never really unmapped certain kinds of tables
after use.

This can cause problems - for example the hypothetical case
when some spurious access still references it.

v2: remove prev_map and prev_size in __apci_map_table
v3: let acpi_os_unmap_memory() call early_iounmap too, so remove extral calling to
early_acpi_os_unmap_memory
v4: fix typo in one acpi_get_table_with_size calling
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

On x86, __acpi_map_table uses early_ioremap() to create the mapping,
replacing the previous mapping with a new one.  Once enough of the
kernel is up an running it switches to using normal ioremap().  At
that point, we need to clean up the final mapping to avoid a warning
from the early_ioremap subsystem.

This can be removed after all the instances in the ACPI code are fixed
that rely on early-ioremap's implicit overmapping of previously
mapped tables.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Always map acpi tables, rather than assuming we can use the normal
linear mapping to access the acpi tables.  This is necessary in a
virtual environment where the linear mappings are to pseudo-physical
memory, but the acpi tables exist at a real physical address.  It
doesn't hurt to map in the normal non-virtual case, so just do it
unconditionally.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

__acpi_map_table() effectively reimplements early_ioremap().  Rather
than have that duplication, just implement it in terms of
early_ioremap().

However, unlike early_ioremap(), __acpi_map_table() just maintains a
single mapping which gets replaced each call, and has no corresponding
unmap function.  Implement this by just removing the previous mapping
each time its called.  Unfortunately, this will leave a stray mapping
at the end.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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>

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>

just like 64 bit switch from flat logical APIC messages to
flat physical mode automatically.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

X86_GENERICARCH is a misnomer - it contains non-PC 32-bit architectures
that are not included in the default build.

Rename it to X86_32_NON_STANDARD.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Spread mach_apic.h definitions into genapic.h. (with some knock-on effects
on smp.h and apic.h.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Move the definition to mpparse.h.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

- separate the namespace

 - remove macros

 - remove namespace clash on 64-bit
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: refactor code

x86 subarchitectures each defined a "acpi_madt_oem_check()" method,
which could be an inline function, or an extern, or a static function,
and which was also the name of a genapic field.

Untangle this namespace spaghetti by setting ->acpi_madt_oem_check()
to NULL on those subarchitectures that have no detection quirks,
and rename the other ones (summit, es7000) that do.

Also change default_acpi_madt_oem_check() to handle NULL entries,
and clean its control flow up as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: cleanup, solve 80 columns wrap problems
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: cleanup, solve 80 columns wrap problems
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

On some boxes there exist both RSDT and XSDT table. But unfortunately
sometimes there exists the following error when XSDT table is used:
   a. 32/64X address mismatch
   b. The 32/64X FACS address mismatch

   In such case the boot option of "acpi=rsdt" is provided so that
RSDT is tried instead of XSDT table when the system can't work well.

http://bugzilla.kernel.org/show_bug.cgi?id=8246Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
cc:Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

Impact: reduce stack size, use new API.

Replace cpumask_t with cpumask_var_t.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: Reduce future system panics due to cpumask operations using NR_CPUS

Insure that code does not look at bits >= nr_cpu_ids as when cpumasks are
allocated based on nr_cpu_ids, these extra bits will not be defined.

Also some other minor updates:

   * change in to use cpu accessor function set_cpu_present() instead of
     directly accessing cpu_present_map w/cpu_clear() [arch/x86/kernel/reboot.c]

   * use cpumask_of() instead of &cpumask_of_cpu() [arch/x86/kernel/reboot.c]

   * optimize some cpu_mask_to_apicid_and functions.
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

When ACPI is asked to find an MADT (APIC table)
and fails, then ACPI expects to run in PIC mode.

However, if an MP Table is was found, IRQs will be
registered as if an IOAPIC is being used, even
though ACPI is configuring interrupt links links for PIC mode.

In this scenario, disable MPS so that IRQs
are registered in PIC mode, consistent with ACPI.

http://bugzilla.kernel.org/show_bug.cgi?id=12257Signed-off-by: Len Brown <len.brown@intel.com>