This patch for SGI UV systems addresses a problem whereby
interrupt transactions being looped back from a local IOH,
through the hub to a local CPU can (erroneously) conflict with
IO port operations and other transactions.

To workaound this we set a high bit in the APIC IDs used for
interrupts. This bit appears to be ignored by the sockets, but
it avoids the conflict in the hub.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
LKML-Reference: <20101116222352.GA8155@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
___

 arch/x86/include/asm/uv/uv_hub.h   |    4 ++++
 arch/x86/include/asm/uv/uv_mmrs.h  |   19 ++++++++++++++++++-
 arch/x86/kernel/apic/x2apic_uv_x.c |   25 +++++++++++++++++++++++--
 arch/x86/platform/uv/tlb_uv.c      |    2 +-
 arch/x86/platform/uv/uv_time.c     |    4 +++-
 5 files changed, 49 insertions(+), 5 deletions(-)

backtrace_mask has been used under the code context of
ARCH_HAS_NMI_WATCHDOG. So put it into that context.
We were warned by the following warning:

  arch/x86/kernel/apic/hw_nmi.c:21: warning: ‘backtrace_mask’ defined but not used

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
LKML-Reference: <1289573455-3410-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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: Don 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: Ingo Molnar <mingo@elte.hu>

Now that we have a new nmi_watchdog that is more generic and
sits on top of the perf subsystem, we really do not need the old
nmi_watchdog any more.

In addition, the old nmi_watchdog doesn't really work if you are
using the default clocksource, hpet.  The old nmi_watchdog code
relied on local apic interrupts to determine if the cpu is still
alive.  With hpet as the clocksource, these interrupts don't
increment any more and the old nmi_watchdog triggers false
postives.

This piece removes the old nmi_watchdog code and stubs out any
variables and functions calls.  The stubs are the same ones used
by the new nmi_watchdog code, so it should be well tested.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: gorcunov@openvz.org
LKML-Reference: <1289578944-28564-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Remove the second <asm/atomic.h> inclusion.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
LKML-Reference: <alpine.LNX.2.00.1011072253360.26247@swampdragon.chaosbits.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

A new version of the SGI UV hub node controller is being
developed. A few of the MMRs (control registers) that exist on
the current hub no longer exist on the new hub. Fortunately,
there are alternate MMRs that are are functionally equivalent
and that exist on both hubs.

This patch changes the UV code to use MMRs that exist in BOTH
versions of the hub node controller.

Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20101106204056.GA27584@sgi.com>
Signed-off-by: Ingo 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: Russ Anderson <rja@sgi.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4CCBD511.40607@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Enable Westmere support for all APIC modes on SGI UV.

Signed-off-by: Russ Anderson <rja@sgi.com>
LKML-Reference: <20101028224132.GB15804@sgi.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Enable Westmere support on SGI UV.  The UV initialization code is dependent on
the APICID bits.  Westmere-EX uses different APIC bit mapping than Nehalem-EX.
This code reads the apic shift value from a UV MMR to do the proper bit
decoding to determint the pnode.

Signed-off-by: Russ Anderson <rja@sgi.com>
LKML-Reference: <20101026212728.GB15071@sgi.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

We want the BIOS to setup the EILVT APIC registers. The offsets
were hardcoded and BIOS settings were overwritten by the OS.
Now, the subsystems for MCE threshold and IBS determine the LVT
offset from the registers the BIOS has setup. If the BIOS setup
is buggy on a family 10h system, a workaround enables IBS. If
the OS determines an invalid register setup, a "[Firmware Bug]:
" error message is reported.

We need this change also for upcomming cpu families.

Signed-off-by: Robert Richter <robert.richter@amd.com>
LKML-Reference: <1286360874-1471-3-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

This patch implements checks for the availability of LVT entries
(APIC500-530) and reserves it if used. The check becomes
necessary since we want to let the BIOS provide the LVT offsets.
 The offsets should be determined by the subsystems using it
like those for MCE threshold or IBS.  On K8 only offset 0
(APIC500) and MCE interrupts are supported. Beginning with
family 10h at least 4 offsets are available.

Since offsets must be consistent for all cores, we keep track of
the LVT offsets in software and reserve the offset for the same
vector also to be used on other cores. An offset is freed by
setting the entry to APIC_EILVT_MASKED.

If the BIOS is right, there should be no conflicts. Otherwise a
"[Firmware Bug]: ..." error message is generated. However, if
software does not properly determines the offsets, it is not
necessarily a BIOS bug.

Signed-off-by: Robert Richter <robert.richter@amd.com>
LKML-Reference: <1286360874-1471-2-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4CBCB274.7010108@kernel.org>
Signed-off-by: Thomas 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: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad 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: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Thomas 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: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>

Instead of looping through all interrupts, use the bitmap lookup to
find the next.

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

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

No users outside of io_apic.c

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

irq_2_iommu is in struct irq_cfg, so we can do the irq_remapped check
based on irq_cfg instead of going through a lookup function. That's
especially interesting in the eoi_ioapic_irq() hotpath.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

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

Switch over to the new allocator and remove all the magic which was
caused by the unability to destroy irq descriptors. Get rid of the
create_irq_nr() loop for sparse and non sparse irq.

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

The sparseirq rework triggered a warning in the iommu code, which was
caused by setting up ioapic for ACPI irq 9 twice. This function is
solely to handle interrupts which are on a secondary ioapic and
outside the legacy irq range.

Replace the sparse irq_to_desc check with a non ifdeffed version.

[ tglx: Moved it before the ioapic sparse conversion and simplified
  	the inverse logic ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4CB00122.3030301@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>

Rename the grossly misnamed get_one_free_irq_cfg() to alloc_irq_cfg().
Add a (not yet used) irq number argument to free_irq_cfg()

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

Implement new allocator functions which make use of the core changes.

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

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

Cleanup after the irq_chip conversion a bit.

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

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

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

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

While at it rename it to sensible function names and fix the return
value from unsigned to int for __ioapic_set_affinity (set_desc_affinity).
Returning -1 in a function returning unsigned int is somewhat strange.

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

Most of it is useless pseudo optimization.

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

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: David Woodhouse <dwmw2@infradead.org>

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

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

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

Sanitize functions. Remove irq_desc pointer magic.
Preparatory patch for further cleanups.

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