linux/kernel/irq
Jon Hunter b62b2cf575 irqdomain: Fix handling of type settings for existing mappings
When mapping an IRQ, it is possible that a mapping for the IRQ already
exists. If mapping does exist then there are the following issues with
regard to the handling of the IRQ type settings ...
1. If the domain is part of a hierarchy, then:
   a. We do not check that the type settings for the existing mapping
      match those of the new mapping.
   b. We do not check to see if the type settings have been programmed
      yet (and they might not have been) and so we may never set the
      type.
2. If the domain is NOT part of a hierarchy, we will overwrite the
   current type settings programmed if they are different from the
   previous mapping. Please note that irq_create_mapping()
   calls irq_find_mapping() to check if a mapping already exists.

Although, it may be unlikely that the type settings for a shared
interrupt would not match, nonetheless we should check for this.
Therefore, to fix this check if a mapping exists (regardless of whether
the domain is part of a hierarchy or not) and if it does then:
1. Return the IRQ number if the type settings match or are not
   specified.
2. Program the type settings and return the IRQ number if the type
   settings have not been programmed yet.
3. Otherwise if the type setting do not match, then print a warning
   and don't return the IRQ number.

Furthermore, add a warning if the type return by irq_domain_translate()
has bits outside the sense mask set and then clear these bits. If these
bits are not cleared then this will cause the comparision of the type
settings for an existing mapping to fail with that of the new mapping
even if the sense bit themselves match. The reason being is that the
existing type settings are read by calling irq_get_trigger_type() which
will clear any bits outside the sense mask. This will allow us to detect
irqchips that are not correctly clearing these bits and fix them.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-06-13 11:53:50 +01:00
..
autoprobe.c genirq: Handle pending irqs in irq_startup() 2012-02-15 11:56:59 +01:00
chip.c genirq: Export IRQ functions for module use 2016-03-10 16:00:35 +01:00
cpuhotplug.c genirq: Make the cpuhotplug migration code less noisy 2015-10-22 14:34:57 +02:00
debug.h irq: hide debug macros so they don't collide with others. 2012-04-23 12:30:03 -04:00
devres.c genirq: devres: Fix testing return value of request_any_context_irq() 2015-05-13 10:47:37 +02:00
dummychip.c Merge branch 'linus' into irq/core 2015-06-05 22:25:01 +02:00
generic-chip.c genirq: Add chip_[suspend|resume] PM support to irq_chip 2015-07-27 08:09:38 +02:00
handle.c genirq: Use a common macro to go through the actions list 2016-02-15 00:07:34 +01:00
internals.h Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-15 12:48:48 -07:00
ipi.c genirq: Fix missing return value in irq_destroy_ipi() 2016-05-24 15:40:14 +02:00
irqdesc.c genirq: Allow the affinity of a percpu interrupt to be set/retrieved 2016-05-02 13:42:51 +02:00
irqdomain.c irqdomain: Fix handling of type settings for existing mappings 2016-06-13 11:53:50 +01:00
Kconfig genirq: Add GENERIC_IRQ_IPI Kconfig symbol 2016-02-25 10:56:55 +01:00
Makefile genirq: Add a new generic IPI reservation code to irq core 2016-02-25 10:56:56 +01:00
manage.c genirq: Ensure IRQ descriptor is valid when setting-up the IRQ 2016-05-11 10:12:41 +01:00
migration.c genirq: Remove bogus restriction in irq_move_mask_irq() 2015-06-20 19:05:14 +02:00
msi.c PCI changes for the v4.5 merge window: 2016-01-21 11:52:16 -08:00
pm.c Merge branches 'irq-urgent-for-linus' and 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-15 09:30:48 -08:00
proc.c genirq: Use a common macro to go through the actions list 2016-02-15 00:07:34 +01:00
resend.c genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
settings.h genirq: Add flag to force mask in disable_irq[_nosync]() 2015-10-11 11:33:42 +02:00
spurious.c genirq: Use a common macro to go through the actions list 2016-02-15 00:07:34 +01:00