Commit Graph

142 Commits

Author SHA1 Message Date
Marc Zyngier b41fdc4a7b irqchip/gic: Drop support for secondary GIC in non-DT systems
We do not have any in-tree platform with this pathological setup,
and only a single system (Cavium's cns3xxx) isn't DT aware.

Let's drop the secondary GIC support for now, until we remove
the above horror altogether.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-03-11 15:38:10 +00:00
Ingo Molnar c5f48c0a7a genirq: Fix various typos in comments
Go over the IRQ subsystem source code (including irqchip drivers) and
fix common typos in comments.

No change in functionality intended.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
2018-12-18 14:22:28 +01:00
Davidlohr Bueso d01d327406 irqchip/gic: Update supports_deactivate static key to modern api
No changes in semantics -- key init is true; replace

static_key_slow_dec       with   static_branch_disable
static_key_true           with   static_branch_likely

The first is because we never actually do any couterpart incs,
thus there is really no reference counting semantics going on.
Use the more proper static_branch_disable() construct.

Also added a '_key' suffix to supports_deactivate, for better
self documentation.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-28 15:24:15 +01:00
Marc Zyngier 83a86fbb5b irqchip/gic: Loudly complain about the use of IRQ_TYPE_NONE
There is a huge number of broken device trees out there. Just
grepping through the tree for the use of IRQ_TYPE_NONE in conjunction
with the GIC is scary.

People just don't realise that IRQ_TYPE_NONE just doesn't exist, and
you just get whatever junk was there before. So let's make them aware
of the issue.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-16 14:35:17 +00:00
Marc Zyngier c5e1035c96 irqchip/gic-v2: Reset APRn registers at boot time
Booting a crash kernel while in an interrupt handler is likely
to leave the Active Priority Registers with some state that
is not relevant to the new kernel, and is likely to lead
to erratic behaviours such as interrupts not firing as their
priority is already active.

As a sanity measure, wipe the APRs clean on startup.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14 11:11:28 +00:00
Linus Torvalds 974aa5630b First batch of KVM changes for 4.15
Common:
  - Python 3 support in kvm_stat
 
  - Accounting of slabs to kmemcg
 
 ARM:
  - Optimized arch timer handling for KVM/ARM
 
  - Improvements to the VGIC ITS code and introduction of an ITS reset
    ioctl
 
  - Unification of the 32-bit fault injection logic
 
  - More exact external abort matching logic
 
 PPC:
  - Support for running hashed page table (HPT) MMU mode on a host that
    is using the radix MMU mode;  single threaded mode on POWER 9 is
    added as a pre-requisite
 
  - Resolution of merge conflicts with the last second 4.14 HPT fixes
 
  - Fixes and cleanups
 
 s390:
  - Some initial preparation patches for exitless interrupts and crypto
 
  - New capability for AIS migration
 
  - Fixes
 
 x86:
  - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs, and
    after-reset state
 
  - Refined dependencies for VMX features
 
  - Fixes for nested SMI injection
 
  - A lot of cleanups
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Merge tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "First batch of KVM changes for 4.15

  Common:
   - Python 3 support in kvm_stat
   - Accounting of slabs to kmemcg

  ARM:
   - Optimized arch timer handling for KVM/ARM
   - Improvements to the VGIC ITS code and introduction of an ITS reset
     ioctl
   - Unification of the 32-bit fault injection logic
   - More exact external abort matching logic

  PPC:
   - Support for running hashed page table (HPT) MMU mode on a host that
     is using the radix MMU mode; single threaded mode on POWER 9 is
     added as a pre-requisite
   - Resolution of merge conflicts with the last second 4.14 HPT fixes
   - Fixes and cleanups

  s390:
   - Some initial preparation patches for exitless interrupts and crypto
   - New capability for AIS migration
   - Fixes

  x86:
   - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs,
     and after-reset state
   - Refined dependencies for VMX features
   - Fixes for nested SMI injection
   - A lot of cleanups"

* tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (89 commits)
  KVM: s390: provide a capability for AIS state migration
  KVM: s390: clear_io_irq() requests are not expected for adapter interrupts
  KVM: s390: abstract conversion between isc and enum irq_types
  KVM: s390: vsie: use common code functions for pinning
  KVM: s390: SIE considerations for AP Queue virtualization
  KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup
  KVM: PPC: Book3S HV: Cosmetic post-merge cleanups
  KVM: arm/arm64: fix the incompatible matching for external abort
  KVM: arm/arm64: Unify 32bit fault injection
  KVM: arm/arm64: vgic-its: Implement KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: vgic-its: Free caches when GITS_BASER Valid bit is cleared
  KVM: arm/arm64: vgic-its: New helper functions to free the caches
  KVM: arm/arm64: vgic-its: Remove kvm_its_unmap_device
  arm/arm64: KVM: Load the timer state when enabling the timer
  KVM: arm/arm64: Rework kvm_timer_should_fire
  KVM: arm/arm64: Get rid of kvm_timer_flush_hwstate
  KVM: arm/arm64: Avoid phys timer emulation in vcpu entry/exit
  KVM: arm/arm64: Move phys_timer_emulate function
  KVM: arm/arm64: Use kvm_arm_timer_set/get_reg for guest register traps
  ...
2017-11-16 13:00:24 -08:00
Christoffer Dall d33a3c8c48 KVM: arm/arm64: Check that system supports split eoi/deactivate
Some systems without proper firmware and/or hardware description data
don't support the split EOI and deactivate operation.

On such systems, we cannot leave the physical interrupt active after the
timer handler on the host has run, so we cannot support KVM with an
in-kernel GIC with the timer changes we are about to introduce.

This patch makes sure that trying to initialize the KVM GIC code will
fail on such systems.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-11-06 16:23:10 +01:00
Marc Zyngier 0962289b1c irqchip/gic: Deal with broken firmware exposing only 4kB of GICv2 CPU interface
There is a lot of broken firmware out there that don't really
expose the information the kernel requires when it comes with dealing
with GICv2:

(1) Firmware that only describes the first 4kB of GICv2
(2) Firmware that describe 128kB of CPU interface, while
    the usable portion of the address space is between
    60 and 68kB

So far, we only deal with (2). But we have platforms exhibiting
behaviour (1), resulting in two sub-cases:
(a) The GIC is occupying 8kB, as required by the GICv2 architecture
(b) It is actually spread 128kB, and this is likely to be a version
    of (2)

This patch tries to work around both (a) and (b) by poking at
the outside of the described memory region, and try to work out
what is actually there. This is of course unsafe, and should
only be enabled if there is no way to otherwise fix the DT provided
by the firmware (we provide a "irqchip.gicv2_force_probe" option
to that effect).

Note that for the time being, we restrict ourselves to GICv2
implementations provided by ARM, since there I have no knowledge
of an alternative implementations. This could be relaxed if such
an implementation comes to light on a broken platform.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-11-02 15:55:44 +00:00
Linus Torvalds 93cc1228b4 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The interrupt subsystem delivers this time:

   - Refactoring of the GIC-V3 driver to prepare for the GIC-V4 support

   - Initial GIC-V4 support

   - Consolidation of the FSL MSI support

   - Utilize the effective affinity interface in various ARM irqchip
     drivers

   - Yet another interrupt chip driver (UniPhier AIDET)

   - Bulk conversion of the irq chip driver to use %pOF

   - The usual small fixes and improvements all over the place"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
  irqchip/ls-scfg-msi: Add MSI affinity support
  irqchip/ls-scfg-msi: Add LS1043a v1.1 MSI support
  irqchip/ls-scfg-msi: Add LS1046a MSI support
  arm64: dts: ls1046a: Add MSI dts node
  arm64: dts: ls1043a: Share all MSIs
  arm: dts: ls1021a: Share all MSIs
  arm64: dts: ls1043a: Fix typo of MSI compatible string
  arm: dts: ls1021a: Fix typo of MSI compatible string
  irqchip/ls-scfg-msi: Fix typo of MSI compatible strings
  irqchip/irq-bcm7120-l2: Use correct I/O accessors for irq_fwd_mask
  irqchip/mmp: Make mmp_intc_conf const
  irqchip/gic: Make irq_chip const
  irqchip/gic-v3: Advertise GICv4 support to KVM
  irqchip/gic-v4: Enable low-level GICv4 operations
  irqchip/gic-v4: Add some basic documentation
  irqchip/gic-v4: Add VLPI configuration interface
  irqchip/gic-v4: Add VPE command interface
  irqchip/gic-v4: Add per-VM VPE domain creation
  irqchip/gic-v3-its: Set implementation defined bit to enable VLPIs
  irqchip/gic-v3-its: Allow doorbell interrupts to be injected/cleared
  ...
2017-09-04 13:08:27 -07:00
Thomas Gleixner 9fbd7fd28d irqchip updates for 4.14
- irqchip-specific part of the monster GICv4 series
 - new UniPhier AIDET irqchip driver
 - new variants of some Freescale MSI widget
 - blanket removal of of_node->full_name in printk
 - random collection of fixes
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Merge tag 'irqchip-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Pull irqchip updates for 4.14 from Marc Zyngier:

- irqchip-specific part of the monster GICv4 series
- new UniPhier AIDET irqchip driver
- new variants of some Freescale MSI widget
- blanket removal of of_node->full_name in printk
- random collection of fixes
2017-08-31 20:12:51 +02:00
Bhumika Goyal 73c4c37c7e irqchip/gic: Make irq_chip const
Make this const as it is only used in a copy operation.
Done using Coccinelle.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-08-31 15:31:43 +01:00
Marc Zyngier 0c9e498286 irqchip/gic: Report that effective affinity is a single target
The GIC driver only targets a single CPU at a time, even if
the notional affinity is wider. Let's inform the core code
about this.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: http://lkml.kernel.org/r/20170818083925.10108-4-marc.zyngier@arm.com
2017-08-18 10:54:40 +02:00
Will Deacon 39a06b67c2 irqchip/gic: Ensure we have an ISB between ack and ->handle_irq
Devices that expose their interrupt status registers via system
registers (e.g. Statistical profiling, CPU PMU, DynamIQ PMU, arch timer,
vgic (although unused by Linux), ...) rely on a context synchronising
operation on the CPU to ensure that the updated status register is
visible to the CPU when handling the interrupt. This usually happens as
a result of taking the IRQ exception in the first place, but there are
two race scenarios where this isn't the case.

For example, let's say we have two peripherals (X and Y), where Y uses a
system register for its interrupt status.

Case 1:
1. CPU takes an IRQ exception as a result of X raising an interrupt
2. Y then raises its interrupt line, but the update to its system
   register is not yet visible to the CPU
3. The GIC decides to expose Y's interrupt number first in the Ack
   register
4. The CPU runs the IRQ handler for Y, but the status register is stale

Case 2:
1. CPU takes an IRQ exception as a result of X raising an interrupt
2. CPU reads the interrupt number for X from the Ack register and runs
   its IRQ handler
3. Y raises its interrupt line and the Ack register is updated, but
   again, the update to its system register is not yet visible to the
   CPU.
4. Since the GIC drivers poll the Ack register, we read Y's interrupt
   number and run its handler without a context synchronisation
   operation, therefore seeing the stale register value.

In either case, we run the risk of missing an IRQ. This patch solves the
problem by ensuring that we execute an ISB in the GIC drivers prior
to invoking the interrupt handler. This is already the case for GICv3
and EOIMode 1 (the usual case for the host).

Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-08-02 16:55:59 +01:00
Suzuki K Poulose 456c59c31c irqchip/gic-v2: Report failures in gic_irq_domain_alloc
If the GIC cannot map an IRQ via irq_domain_ops->alloc(), it doesn't
return an error code.  This can cause a problem with drivers, where
it thinks it has successfully got an IRQ for the device, but requesting
the same ends up failure with -ENOSYS (as the IRQ's chip is not set).

Fixes: commit 9a1091ef00 ("irqchip: gic: Support hierarchy irq domain.")
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-07-04 11:11:25 +01:00
Thomas Gleixner 73c1b41e63 cpu/hotplug: Cleanup state names
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.

Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-25 10:47:44 +01:00
Marc Zyngier fd5bed48b4 irqchip/gic: Add missing \n to CPU IF adjustment message
It really looks bad without a newline.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-10-20 11:21:01 +01:00
Baoyou Xie 89c59cca48 irqchip/gic: Mark gic_init_physaddr() static
We get 1 warning when building kernel with W=1:
drivers/irqchip/irq-gic.c:917:13: warning: no previous prototype for 'gic_init_physaddr' [-Wmissing-prototypes]

In fact, this function is only used in the file in which it is
declared and don't need a declaration, but can be made static.
so this patch marks this function with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-09-12 19:46:28 +01:00
Marc Zyngier 04c8b0f82c irqchip/gic: Make locking a BL_SWITCHER only feature
The BL switcher code manipulates the logical/physical CPU mapping,
forcing a lock to be taken on the IPI path. With an IPI heavy load,
this single lock becomes contended.

But when CONFIG_BL_SWITCHER is not enabled, there is no reason
to take this lock at all since the CPU mapping is immutable.

This patch allows the lock to be entierely removed when BL_SWITCHER
is not enabled (which is the case in most configurations), leading
to a small improvement of "perf bench sched pipe" (measured on
an 8 core AMD Seattle system):

Before: 101370 ops/sec
After:  103680 ops/sec

Take this opportunity to remove a useless lock being taken when
handling an interrupt on a secondary GIC.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-09-12 19:46:19 +01:00
Marc Zyngier 059e232089 irqchip/gic: Allow self-SGIs for SMP on UP configurations
On systems where a single CPU is present, the GIC may not support
having SGIs delivered to a target list. In that case, we use the
self-SGI mechanism to allow the interrupt to be delivered locally.

Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-08-17 18:31:20 +01:00
Linus Torvalds a6408f6cb6 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull smp hotplug updates from Thomas Gleixner:
 "This is the next part of the hotplug rework.

   - Convert all notifiers with a priority assigned

   - Convert all CPU_STARTING/DYING notifiers

     The final removal of the STARTING/DYING infrastructure will happen
     when the merge window closes.

  Another 700 hundred line of unpenetrable maze gone :)"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  timers/core: Correct callback order during CPU hot plug
  leds/trigger/cpu: Move from CPU_STARTING to ONLINE level
  powerpc/numa: Convert to hotplug state machine
  arm/perf: Fix hotplug state machine conversion
  irqchip/armada: Avoid unused function warnings
  ARC/time: Convert to hotplug state machine
  clocksource/atlas7: Convert to hotplug state machine
  clocksource/armada-370-xp: Convert to hotplug state machine
  clocksource/exynos_mct: Convert to hotplug state machine
  clocksource/arm_global_timer: Convert to hotplug state machine
  rcu: Convert rcutree to hotplug state machine
  KVM/arm/arm64/vgic-new: Convert to hotplug state machine
  smp/cfd: Convert core to hotplug state machine
  x86/x2apic: Convert to CPU hotplug state machine
  profile: Convert to hotplug state machine
  timers/core: Convert to hotplug state machine
  hrtimer: Convert to hotplug state machine
  x86/tboot: Convert to hotplug state machine
  arm64/armv8 deprecated: Convert to hotplug state machine
  hwtracing/coresight-etm4x: Convert to hotplug state machine
  ...
2016-07-29 13:55:30 -07:00
Richard Cochran 93131f7a9b irqchip/gic: Convert to hotplug state machine
More or less straightforward, although this driver sports some very
interesting SMP setup code. Regarding the callback ordering, this
deleted comment is interesting:

   ... the GIC needs to be up before the ARM generic timers.

That comment is half baken as the same requirement is true for perf.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153333.069777215@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 09:34:28 +02:00
Jon Hunter 9c8edddfc9 irqchip/gic: Add platform driver for non-root GICs that require RPM
Add a platform driver to support non-root GICs that require runtime
power-management. Currently, only non-root GICs are supported because
the functions, smp_cross_call() and set_handle_irq(), that need to
be called for a root controller are located in the __init section and
so cannot be called by the platform driver.

The GIC platform driver re-uses many functions from the existing GIC
driver including some functions to save and restore the GIC context
during power transitions. The functions for saving and restoring the
GIC context are currently only defined if CONFIG_CPU_PM is enabled and
to ensure that these functions are always defined when the platform
driver is enabled, a dependency on CONFIG_ARM_GIC_PM (which selects the
platform driver) has been added.

In order to re-use the private GIC initialisation code, a new public
function, gic_of_init_child(), has been added which calls various
private functions to initialise the GIC. This is different from the
existing gic_of_init() because it only supports non-root GICs (ie. does
not call smp_cross_call() is set_handle_irq()) and is not located in
the __init section (so can be used by platform drivers). Furthermore,
gic_of_init_child() dynamically allocates memory for the GIC chip data
which is also different from gic_of_init().

There is no specific suspend handling for GICs registered as platform
devices. Non-wakeup interrupts will be disabled by the kernel during
late suspend, however, this alone will not power down the GIC if
interrupts have been requested and not freed. Therefore, requestors of
non-wakeup interrupts will need to free them on entering suspend in
order to power-down the GIC.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-06-13 11:53:52 +01:00
Jon Hunter cdbb813db6 irqchip/gic: Prepare for adding platform driver
To support GICs that require runtime power management, it is necessary
to add a platform driver, so that the probing of the chip can be
deferred if resources, such as a power-domain, is not yet available.

To prepare for adding a platform driver:
 1. Drop the __init section from the gic_dist_config() so this can be
    re-used by the platform driver.
 2. Add prototypes for functions required by the platform driver to the
    GIC header file so they can be re-used.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-06-13 11:53:52 +01:00
Jon Hunter faea645585 irqchip/gic: Add helper function for chip initialisation
For GICs that require runtime power-management it is necessary to
populate the 'parent_device' member of the irqchip structure. In
preparation for supporting such GICs, move the code that initialises
the irqchip structure for a GIC into its own function called
gic_init_chip() where the parent device pointer is also set.

Instead of calling gic_init_chip() from within gic_init_bases(), move
the calls to outside of this function, so that in the future we can
avoid having to pass additional parameters to gic_init_bases() in order
set the parent device pointer or set the name to a specific string.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-06-13 11:53:52 +01:00
Jon Hunter d6ce564cea irqchip/gic: Isolate early GIC initialisation code
To re-use the code that initialises the GIC (found in
__gic_init_bases()), from within a platform driver, it is necessary to
move the code from the __init section so that it is always present and
not removed. Unfortunately, it is not possible to simply drop the __init
from the function declaration for __gic_init_bases() because it contains
calls to set_smp_cross_call() and set_handle_irq() which are both
located in the __init section. Fortunately, these calls are only
required for the root controller and because the initial platform driver
will only support non-root controllers that can be initialised later in
the boot process, we can move these calls to another function.

Move the bulk of the code from __gic_init_bases() to a new function
called gic_init_bases() which is not located in the __init section and
can be used by the platform driver. Update __gic_init_bases() to call
gic_init_bases() and if necessary, set_smp_cross_call() and
set_handle_irq().

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-06-13 11:53:51 +01:00
Arnd Bergmann 287980e49f remove lots of IS_ERR_VALUE abuses
Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
       unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> # For nvmem part
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-27 15:26:11 -07:00
Linus Torvalds 7beaa24ba4 Small release overall.
- x86: miscellaneous fixes, AVIC support (local APIC virtualization,
 AMD version)
 
 - s390: polling for interrupts after a VCPU goes to halted state is
 now enabled for s390; use hardware provided information about facility
 bits that do not need any hypervisor activity, and other fixes for
 cpu models and facilities; improve perf output; floating interrupt
 controller improvements.
 
 - MIPS: miscellaneous fixes
 
 - PPC: bugfixes only
 
 - ARM: 16K page size support, generic firmware probing layer for
 timer and GIC
 
 Christoffer Dall (KVM-ARM maintainer) says:
 "There are a few changes in this pull request touching things outside
  KVM, but they should all carry the necessary acks and it made the
  merge process much easier to do it this way."
 
 though actually the irqchip maintainers' acks didn't make it into the
 patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
 later acked at http://mid.gmane.org/573351D1.4060303@arm.com
 "more formally and for documentation purposes".
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Small release overall.

  x86:
   - miscellaneous fixes
   - AVIC support (local APIC virtualization, AMD version)

  s390:
   - polling for interrupts after a VCPU goes to halted state is now
     enabled for s390
   - use hardware provided information about facility bits that do not
     need any hypervisor activity, and other fixes for cpu models and
     facilities
   - improve perf output
   - floating interrupt controller improvements.

  MIPS:
   - miscellaneous fixes

  PPC:
   - bugfixes only

  ARM:
   - 16K page size support
   - generic firmware probing layer for timer and GIC

  Christoffer Dall (KVM-ARM maintainer) says:
    "There are a few changes in this pull request touching things
     outside KVM, but they should all carry the necessary acks and it
     made the merge process much easier to do it this way."

  though actually the irqchip maintainers' acks didn't make it into the
  patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
  later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more
  formally and for documentation purposes')"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits)
  KVM: MTRR: remove MSR 0x2f8
  KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same
  svm: Manage vcpu load/unload when enable AVIC
  svm: Do not intercept CR8 when enable AVIC
  svm: Do not expose x2APIC when enable AVIC
  KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore
  svm: Add VMEXIT handlers for AVIC
  svm: Add interrupt injection via AVIC
  KVM: x86: Detect and Initialize AVIC support
  svm: Introduce new AVIC VMCB registers
  KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick
  KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks
  KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks
  KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg
  KVM: x86: Misc LAPIC changes to expose helper functions
  KVM: shrink halt polling even more for invalid wakeups
  KVM: s390: set halt polling to 80 microseconds
  KVM: halt_polling: provide a way to qualify wakeups during poll
  KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts
  kvm: Conditionally register IRQ bypass consumer
  ...
2016-05-19 11:27:09 -07:00
Linus Torvalds ede40902cf Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "This update delivers:

   - Yet another interrupt chip diver (LPC32xx)
   - Core functions to handle partitioned per-cpu interrupts
   - Enhancements to the IPI core
   - Proper handling of irq type configuration
   - A large set of ARM GIC enhancements
   - The usual pile of small fixes, cleanups and enhancements"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
  irqchip/bcm2836: Use a more generic memory barrier call
  irqchip/bcm2836: Fix compiler warning on 64-bit build
  irqchip/bcm2836: Drop smp_set_ops on arm64 builds
  irqchip/gic: Add helper functions for GIC setup and teardown
  irqchip/gic: Store GIC configuration parameters
  irqchip/gic: Pass GIC pointer to save/restore functions
  irqchip/gic: Return an error if GIC initialisation fails
  irqchip/gic: Remove static irq_chip definition for eoimode1
  irqchip/gic: Don't initialise chip if mapping IO space fails
  irqchip/gic: WARN if setting the interrupt type for a PPI fails
  irqchip/gic: Don't unnecessarily write the IRQ configuration
  irqchip: Mask the non-type/sense bits when translating an IRQ
  genirq: Ensure IRQ descriptor is valid when setting-up the IRQ
  irqchip/gic-v3: Configure all interrupts as non-secure Group-1
  irqchip/gic-v2m: Add workaround for Broadcom NS2 GICv2m erratum
  irqchip/irq-alpine-msi: Don't use <asm-generic/msi.h>
  irqchip/mbigen: Checking for IS_ERR() instead of NULL
  irqchip/gic-v3: Remove inexistant register definition
  irqchip/gicv3-its: Don't allow devices whose ID is outside range
  irqchip: Add LPC32xx interrupt controller driver
  ...
2016-05-17 10:27:29 -07:00
Jon Hunter d6490461a1 irqchip/gic: Add helper functions for GIC setup and teardown
Move the code that sets-up a GIC via device-tree into it's own
function and add a generic function for GIC teardown that can be used
for both device-tree and ACPI to unmap the GIC memory.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-11 10:12:44 +01:00
Jon Hunter f673b9b5cb irqchip/gic: Store GIC configuration parameters
Store the GIC configuration parameters in the GIC chip data structure.
This will allow us to simplify the code by reducing the number of
parameters passed between functions.

Update the __gic_init_bases() function so that we only need to pass a
pointer to the GIC chip data structure and no longer need to pass the
GIC index in order to look-up the chip data.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-11 10:12:44 +01:00
Jon Hunter 6e5b5924d9 irqchip/gic: Pass GIC pointer to save/restore functions
Instead of passing the GIC index to the save/restore functions pass a
pointer to the GIC chip data. This will allow these save/restore
functions to be re-used by a platform driver where the GIC chip data
structure is allocated dynamically and so there is no applicable index
for identifying the GIC.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-11 10:12:43 +01:00
Jon Hunter dc9722cc57 irqchip/gic: Return an error if GIC initialisation fails
If the GIC initialisation fails, then currently we do not return an error
or clean-up afterwards. Although for root controllers, this failure may be
fatal anyway, for secondary controllers, it may not be fatal and so return
an error on failure and clean-up.

Update the functions gic_cpu_init() and gic_pm_init() to return an error
instead of calling BUG() and perform any necessary clean-up.

For non-banked GIC controllers, make sure that we free any memory
allocated if we fail to initialise the IRQ domain. Please note that
free_percpu() only frees memory if the pointer passed to it is not NULL
and so it is unnecessary to check if both pointers are valid or not.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-11 10:12:43 +01:00
Jon Hunter c2baa2f3f4 irqchip/gic: Remove static irq_chip definition for eoimode1
There are only 3 differences (not including the name) in the definitions
of the gic_chip and gic_eoimode1_chip structures. Instead of statically
defining the gic_eoimode1_chip structure, remove it and populate the
eoimode1 functions dynamically for the appropriate GIC irqchips.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-11 10:12:43 +01:00
Jon Hunter 26acfe7463 irqchip/gic: Don't initialise chip if mapping IO space fails
If we fail to map the address space for the GIC distributor or CPU
interface, then don't attempt to initialise the chip, just WARN and
return.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-11 10:12:42 +01:00
Will Deacon f86c4fbd93 irqchip/gic: Ensure ordering between read of INTACK and shared data
When an IPI is generated by a CPU, the pattern looks roughly like:

  <write shared data>
  smp_wmb();
  <write to GIC to signal SGI>

On the receiving CPU we rely on the fact that, once we've taken the
interrupt, then the freshly written shared data must be visible to us.
Put another way, the CPU isn't going to speculate taking an interrupt.

Unfortunately, this assumption turns out to be broken.

Consider that CPUx wants to send an IPI to CPUy, which will cause CPUy
to read some shared_data. Before CPUx has done anything, a random
peripheral raises an IRQ to the GIC and the IRQ line on CPUy is raised.
CPUy then takes the IRQ and starts executing the entry code, heading
towards gic_handle_irq. Furthermore, let's assume that a bunch of the
previous interrupts handled by CPUy were SGIs, so the branch predictor
kicks in and speculates that irqnr will be <16 and we're likely to
head into handle_IPI. The prefetcher then grabs a speculative copy of
shared_data which contains a stale value.

Meanwhile, CPUx gets round to updating shared_data and asking the GIC
to send an SGI to CPUy. Internally, the GIC decides that the SGI is
more important than the peripheral interrupt (which hasn't yet been
ACKed) but doesn't need to do anything to CPUy, because the IRQ line
is already raised.

CPUy then reads the ACK register on the GIC, sees the SGI value which
confirms the branch prediction and we end up with a stale shared_data
value.

This patch fixes the problem by adding an smp_rmb() to the IPI entry
code in gic_handle_irq. As it turns out, the combination of a control
dependency and an ISB instruction from the EOI in the GICv3 driver is
enough to provide the ordering we need, so we add a comment there
justifying the absence of an explicit smp_rmb().

Cc: stable@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-11 10:11:51 +01:00
Julien Grall 502d6df11a irqchip/gic-v2: Parse and export virtual GIC information
For now, the firmware tables are parsed 2 times: once in the GIC
drivers, the other timer when initializing the vGIC. It means code
duplication and make more tedious to add the support for another
firmware table (like ACPI).

Introduce a new structure and set of helpers to get/set the virtual GIC
information. Also fill up the structure for GICv2.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-03 12:54:21 +02:00
Julien Grall bafa9193d0 irqchip/gic-v2: Gather ACPI specific data in a single structure
The ACPI code requires to use global variables in order to collect
information from the tables.

For now, a single global variable is used, but more will be added in a
subsequent patch. To make clear they are ACPI specific, gather all the
information in a single structure.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christofer Dall <christoffer.dall@linaro.org>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-03 12:54:21 +02:00
Marc Zyngier 25fc11aead irqchip/gic: Restore CPU interface checking
When introducing the whole CPU feature detection framework,
we lost the capability to detect a mismatched GIC configuration
(using the GICv2 MMIO interface, but having the system register
interface enabled).

In order to solve this, use the new this_cpu_has_cap() helper.
Also move the check to the CPU interface path in order to catch
systems where the first CPU has been correctly configured,
but the secondaries are not.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-25 15:14:00 +01:00
Ingo Molnar fe36d8912c Merge branch 'linus' into irq/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-08 12:26:07 +01:00
Marc Zyngier 0407daceed irqchip/gic: Return IRQ_SET_MASK_OK_DONE in the set_affinity method
Moving an SPI around doesn't require any extra work from the rest
of the stack, and specially not for MSI-generated SPIs.

It is then worth returning IRQ_SET_MASK_OK_DONE instead of
IRQ_SET_MASK_OK, and simplify the other irqchips that rely on
this behaviour (GICv2m and Marvell's ODMI controller).

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1455894029-17270-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2016-02-19 15:42:29 +00:00
Jon Hunter 389a00d3ad irqchip/gic: Only set the EOImodeNS bit for the root controller
EOImode1 is only used for the root controller and hence only the root
controller uses the eoimode1 functions for handling interrupts. However,
if the root controller supports EOImode1, then the EOImodeNS bit will be
set for all GICs, enabling EOImode1. This is not what we want and this
causes interrupts on non-root GICs to only be dropped in priority but
never deactivated. Therefore, only set the EOImodeNS bit for the root
controller.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-11 10:20:02 +00:00
Jon Hunter 7bf29d3af6 irqchip/gic: Only populate set_affinity for the root controller
Setting the affinity of an IRQ, it only applicable for the root
interrupt controller and so only populate this operator for the root
controller.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-11 10:20:02 +00:00
Thomas Gleixner 92b86f92ed Merge branch 'irq/gic-v2m-acpi' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull another round of GIC changes from Marc:

 ACPI support for GIV-v2m
2015-12-29 10:08:45 +01:00
Suravee Suthikulpanit 0644b3daca irqchip/gic-v2m: acpi: Introducing GICv2m ACPI support
This patch introduces gicv2m_acpi_init(), which uses information
in MADT GIC MSI frames structure to initialize GICv2m driver.
It also exposes gicv2m_init() function, which simplifies callers
to a single GICv2m init function.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Duc Dang <dhdang@apm.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-21 15:43:35 +00:00
Suravee Suthikulpanit 75aba7b0e9 irqdomain: Introduce is_fwnode_irqchip helper
Since there will be several places checking if fwnode.type
is equal FWNODE_IRQCHIP, this patch adds a convenient function
for this purpose.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-21 13:49:49 +00:00
Linus Walleij a27d21e03e irqchip/gic: Kconfig the number of instances
There is currently a hack in the GIC driver making it possible
to pass the number of GIC instances from the platform-specific
include files and thus override the variable MAX_GIC_NR.

With multiplatform deployments, this will not work as we need
to get rid of the platform-specific include files.

It turns out that this feature is only used by the RealView
platform which has a cascaded GIC. So move the configuration
to Kconfig and bump to 2 instances if we're building for the
RealView. The include file hacks can then be removed.

Tested on the ARM PB11MPCore with its cascaded GIC.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-18 10:37:00 +00:00
Marc Zyngier 327ebe1f3a irqchip/gic: Make interrupt ID 1020 invalid
The GIC has no such thing as interrupt 1020: the last valid ID is
1019, and the range 1020-1023 is reserved - 1023 indicating that
no interrupt is pending. So let's make sure we don't try to handle
this ID.

This bug has been in since the initial GIC code was introduced in
8ad68bbf7a ("[ARM] Add support for ARM RealView board").

Reported-by: Eric Auger <eric.auger@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-16 15:30:51 +00:00
Linus Walleij 58b8964990 irqchip/gic: Assign irqchip dynamically
Instead of having the irqchip being a static struct, make it part
of the per-instance data so we can assign it a dynamic name. This
has the usable side effect of displaying the GIC with an instance
number as GIC0, GIC1 ... GICn in /proc/interrupts, which is helpful
when debugging cascaded GICs, such as on the ARM PB11MPCore.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-16 15:30:50 +00:00
Linus Walleij 8673c1d7e8 irqchip/gic: Support RealView variant setup
The ARM RealView PB11MPCore reference design has some special
bits in a system controller register to set up the GIC in one
of three modes: legacy, new with DCC, new without DCC. The
register is also used to enable FIQ.

Since the platform will not boot unless this register is set
up to "new with DCC" mode, we need a special quirk to be
compiled-in for the RealView platforms.

If we find the right compatible string on the GIC TestChip,
we enable this quirk by looking up the system controller and
enabling the special bits.

We depend on the CONFIG_REALVIEW_DT Kconfig symbol as the old
boardfile code has the same fix hardcoded, and this is only
needed for the attempts to modernize the RealView code using
device tree.

After fixing this, the PB11MPCore boots with device tree
only.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-16 15:30:50 +00:00
Marc Zyngier 1c7d4dd46e irqchip/gic: Add save/restore of the active state
When using EOImode==1, we may mark interrupts as being forwarded
to a virtual machine. In that case, the interrupt is left active
while being passed to the VM.

If we suspend the system before the VM has deactivated the interrupt,
the active state will be lost (which may be very annoying, as this
may result in spurious interrupts and a confused guest).

To avoid this, save and restore the active state together with the
rest of the GIC registers.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/1447701208-18150-5-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-11-17 14:25:59 +01:00