We use io_apic_setup_irq_pin() in order to configure pin's interrupt
number polarity and type. This is done on every irq_create_of_mapping()
which happens for instance during pci enable calls. Level typed
interrupts are masked by default, edge are unmasked.

On the first ->xlate() call the level interrupt is configured and
masked. The driver calls request_irq() and the line is unmasked. Lets
assume the interrupt line is shared with another device and we call
pci_enable_device() for this device. The ->xlate() configures the pin
again and it is masked. request_irq() does not unmask the line because
it _is_ already unmasked according to its internal state. So the
interrupt will never be unmasked again.

This patch is based on an earlier work by Torben Hohn and solves the
problem by configuring the pin only once. Since all devices must agree
on the same type and polarity there is no point in configuring the pin
more than once.

[ tglx: Split out the ce4100 part into a separate patch ]

Cc: Torben Hohn <torbenh@linutronix.de>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/%3C20110427143052.GA15211%40linutronix.de%3ESigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Some subsystems in the x86 tree need to carry out suspend/resume and
shutdown operations with one CPU on-line and interrupts disabled and
they define sysdev classes and sysdevs or sysdev drivers for this
purpose.  This leads to unnecessarily complicated code and excessive
memory usage, so switch them to using struct syscore_ops objects for
this purpose instead.

Generally, there are three categories of subsystems that use
sysdevs for implementing PM operations: (1) subsystems whose
suspend/resume callbacks ignore their arguments entirely (the
majority), (2) subsystems whose suspend/resume callbacks use their
struct sys_device argument, but don't really need to do that,
because they can be implemented differently in an arguably simpler
way (io_apic.c), and (3) subsystems whose suspend/resume callbacks
use their struct sys_device argument, but the value of that argument
is always the same and could be ignored (microcode_core.c).  In all
of these cases the subsystems in question may be readily converted to
using struct syscore_ops objects for power management and shutdown.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NIngo Molnar <mingo@elte.hu>

They were generated by 'codespell' and then manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: trivial@kernel.org
LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The caller of ioapic_register_intr() has a pointer to the irq_cfg for
the irq already. Hand it in to avoid a full lookup.

In msi_compose_msg() the pointer to irq_cfg is already available. No
need to look it up again.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use the functions which take irq_data. We already have a pointer to
irq_data. That avoids a sparse irq lookup in move_*_irq.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use the state information in irq_data. That avoids a radix-tree lookup
from apic_ack_level() and simplifies setup_ioapic_dest().
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use pointers instead of ugly multiline if/else constructs.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

genirq is switching to a consistent name space for the irq related
functions. Convert x86. Conversion was done with coccinelle.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Required for devicetree based io_apic configuration.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

io_apic_set_pci_routing() and mp_save_irq() check the pin_programmed
bit before calling io_apic_setup_irq_pin() and set the bit when the
pin was setup.

Move that duplicated code into a separate function and use it.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

There is no point to have irq_trigger() and irq_polarity() as wrappers
around the MPBIOS_* camel case functions. Get rid of both the inlines
and the ugly camel case.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

No users outside of io_apic.c. Mark bad_ioapic() __init while at it.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Another version of the same thing. Only set the pin programmed, when
the setup function succeeds.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Replace the duplicated code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The only difference here is that we did not call
__add_pin_to_irq_node() for the legacy irqs, but that's not worth 30
lines of extra code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Remove the duplicated code and call the function. It does not matter
whether we allocated the cfg before calling setup_local_APIC() and we
can set the irq chip and handler after that as well.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

There are about four places in the ioapic code which do exactly the
same setup sequence. Also the OF based ioapic setup needs that
function to avoid putting the OF specific code into ioapic.c
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Two consecutive

    for(...)
    for(...)

lines to avoid an extra indentation are just horrible to read. I had
to look more than once to figure out what the code is doing.

Split out the inner loop into a separate function.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This is debug code and it does not matter at all whether we print each
not connected pin in an extra line or try to be extra clever.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Currently arch_disable_smp_support() on x86 disables only the
support for the IOAPIC and is also compiled in if SMP-support is
not.

Therefore this function is renamed to disable_ioapic_support(),
which meets its purpose and is only compiled in the kernel
when IOAPIC support is also.

A new arch_disable_smp_support() is created in smpboot.c,
which calls disable_ioapic_support() and gets only compiled
in the kernel when SMP support is also.
Signed-off-by: NHenrik Kretzschmar <henne@nachtwindheim.de>
LKML-Reference: <1298385487-4708-3-git-send-email-henne@nachtwindheim.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

mp_find_ioapic() prints errors like:

    ERROR: Unable to locate IOAPIC for GSI 13

if it can't find the IOAPIC that manages that specific GSI. I
see errors like that at every boot of a laptop that apparently
doesn't have any IOAPICs.

But if there are no IOAPICs it doesn't seem to be an error that
none can be found. A solution that gets rid of this message is
to directly return if nr_ioapics (still) is zero. (But keep
returning -1 in that case, so nothing breaks from this change.)

The call chain that generates this error is:

pnpacpi_allocated_resource()
    case ACPI_RESOURCE_TYPE_IRQ:
        pnpacpi_parse_allocated_irqresource()
            acpi_get_override_irq()
                 mp_find_ioapic()
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Found one x2apic pre-enabled system, x2apic_mode suddenly get
corrupted after register some cpus, when compiled
CONFIG_NR_CPUS=255 instead of 512.

It turns out that generic_processor_info() ==> phyid_set(apicid,
phys_cpu_present_map) causes the problem.

phys_cpu_present_map is sized by MAX_APICS bits, and pre-enabled
system some cpus have an apic id > 255.

The variable after phys_cpu_present_map may get corrupted
silently:

 ffffffff828e8420 B phys_cpu_present_map
 ffffffff828e8440 B apic_verbosity
 ffffffff828e8444 B local_apic_timer_c2_ok
 ffffffff828e8448 B disable_apic
 ffffffff828e844c B x2apic_mode
 ffffffff828e8450 B x2apic_disabled
 ffffffff828e8454 B num_processors
 ...

Actually phys_cpu_present_map is referenced via apic id, instead
index. We should use MAX_LOCAL_APIC instead MAX_APICS.

For 64-bit it will be 32768 in all cases. BSS will increase by 4k bytes
on 64-bit:

	text		data		bss		dec		filename
	21696943	4193748		12787712	38678403	vmlinux.before
	21696943	4193748		12791808	38682499	vmlinux.after

No change on 32bit.

Finally we can remove MAX_APCIS that was rather confusing.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
LKML-Reference: <4D23BD9C.3070102@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Go through x86 code and replace __get_cpu_var and get_cpu_var
instances that refer to a scalar and are not used for address
determinations.

Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: N"H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

In x2apic mode, we need to set the upper address register of the fault
handling interrupt register of the vt-d hardware. Without this
irq migration of the vt-d fault handling interrupt is broken.
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
LKML-Reference: <1291225233.2648.39.camel@sbsiddha-MOBL3>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: stable@kernel.org [v2.6.32+]
Acked-by: NChris Wright <chrisw@sous-sol.org>
Tested-by: NTakao Indoh <indou.takao@jp.fujitsu.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

assign_to_mp_irq() is copying the struct mpc_intsrc members one by
one. That's silly. Use memcpy() and let the compiler figure it out.
Same for the identical function assign_to_mpc_intsrc()

mp_irq_mpc_intsrc_cmp() is comparing the struct members one by one,
but no caller ever checks the different return codes. Use memcmp()
instead.

Remove the extra printk in MP_ioapic_info()
Signed-off-by: NFeng Tang <feng.tang@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Alan Cox <alan@linux.intel.com>
Cc: Len Brown <len.brown@intel.com>
LKML-Reference: <20101208151857.212f0018@feng-i7>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

There are 3 places defining similar functions of saving IRQ vector
info into mp_irqs[] array: mmparse/acpi/mrst.

Replace the redundant code by a common function in io_apic.c as it's
only called when CONFIG_X86_IO_APIC=y
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20101207133204.4d913c5a@feng-i7>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

For 32bit mptable path, setup_ids_from_mpc() always writes the io_apic
id register, even there is no change needed.

Skip the write, when readout and mptable match.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
LKML-Reference: <4CFDF785.7010401@kernel.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/apic/io_apic.c: In function 'ack_apic_level':
arch/x86/kernel/apic/io_apic.c:2433: warning: unused variable 'desc'
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
LKML-Reference: <201010272107.o9RL7rse018212@imap1.linux-foundation.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Sodaville needs to setup the IO_APIC ids as the boot loader leaves
them uninitialized. Split out the setter function so it can be called
unconditionally from the sodaville board code.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20101126165020.GA26361@www.tglx.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Now that the bulk of the old nmi_watchdog is gone, remove all
the stub variables and hooks associated with it.

This touches lots of files mainly because of how the io_apic
nmi_watchdog was implemented.  Now that the io_apic nmi_watchdog
is forever gone, remove all its fingers.

Most of this code was not being exercised by virtue of
nmi_watchdog != NMI_IO_APIC, so there shouldn't be anything to
risky here.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: gorcunov@openvz.org
LKML-Reference: <1289578944-28564-3-git-send-email-dzickus@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Russ Anderson reported:
| There is a regression that is causing a NULL pointer dereference
| in free_irte when shutting down xpc. git bisect narrowed it down
| to git commit d585d060(intr_remap: Simplify the code further), which
| changed free_irte(). Reverse applying the patch fixes the problem.

We need to use irq_remapped() for each irq instead of checking only
intr_remapping_enabled as there might be non remapped irqs even when
remapping is enabled.

[ tglx: use cfg instead of retrieving it again. Massaged changelog ]
Reported-bisected-and-tested-by: NRuss Anderson <rja@sgi.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4CCBD511.40607@kernel.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

probe_br_irqs_gsi() is called right after ioapic_init_mappings() and
there are no other users. Move it into ioapic_init_mappings() so the
declaration can disappear and the function can become static.

Rename ioapic_init_mappings() to ioapic_and_gsi_init() to reflect that
change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <1287510389-8388-2-git-send-email-dirk.brandewie@gmail.com>
Signed-off-by: NDirk Brandewie <dirk.j.brandewie@intel.com>

On a system that support intr-rempping when booting with "intremap=off"

[  177.895501] BUG: unable to handle kernel NULL pointer dereference at 00000000000000f8
[  177.913316] IP: [<ffffffff8145fc18>] free_irte+0x47/0xc0
...
[  178.173326] Call Trace:
[  178.173574]  [<ffffffff810515b4>] destroy_irq+0x3a/0x75
[  178.192934]  [<ffffffff81051834>] arch_teardown_msi_irq+0xe/0x10
[  178.193418]  [<ffffffff81458dc3>] arch_teardown_msi_irqs+0x56/0x7f
[  178.213021]  [<ffffffff81458e79>] free_msi_irqs+0x8d/0xeb

Call free_irte only when interrupt remapping is enabled.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4CBCB274.7010108@kernel.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Introduce an x86 specific indirect mechanism to setup MSIs.
The MSI setup functions become function pointers in an x86_msi_ops
struct, that defaults to the implementation in io_apic.c and msi.c.

[v2: Use HAVE_DEFAULT_* knobs]
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

Impact: new interface to get max GSI

Add get_nr_irqs_gsi() to return nr_irqs_gsi.  Xen will use this to
determine how many irqs it needs to reserve for hardware irqs.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: N"H. Peter Anvin" <hpa@zytor.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

No callers from atomic context (except boot) anymore.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NIngo Molnar <mingo@elte.hu>

Instead of looping through all interrupts, use the bitmap lookup to
find the next.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NIngo Molnar <mingo@elte.hu>

No users outside of io_apic.c
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NIngo Molnar <mingo@elte.hu>