linux/include
Marc Zyngier 530cbe100e irqdomain: Allow domain lookup with DOMAIN_BUS_WIRED token
Let's take the (outlandish) example of an interrupt controller
capable of handling both wired interrupts and PCI MSIs.

With the current code, the PCI MSI domain is going to be tagged
with DOMAIN_BUS_PCI_MSI, and the wired domain with DOMAIN_BUS_ANY.

Things get hairy when we start looking up the domain for a wired
interrupt (typically when creating it based on some firmware
information - DT or ACPI).

In irq_create_fwspec_mapping(), we perform the lookup using
DOMAIN_BUS_ANY, which is actually used as a wildcard. This gives
us one chance out of two to end up with the wrong domain, and
we try to configure a wired interrupt with the MSI domain.
Everything grinds to a halt pretty quickly.

What we really need to do is to start looking for a domain that
would uniquely identify a wired interrupt domain, and only use
DOMAIN_BUS_ANY as a fallback.

In order to solve this, let's introduce a new DOMAIN_BUS_WIRED
token, which is going to be used exactly as described above.
Of course, this depends on the irqchip to setup the domain
bus_token, and nobody had to implement this so far.

Only so far.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Link: http://lkml.kernel.org/r/1453816347-32720-2-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-01-26 16:00:14 +01:00
..
acpi Merge branch 'acpi-pci' 2015-11-07 01:30:10 +01:00
asm-generic Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-01-11 17:16:01 -08:00
clocksource
crypto Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2015-11-05 15:32:38 -08:00
drm drm/nouveau: Fix pre-nv50 pageflip events (v4) 2015-12-04 13:49:38 +10:00
dt-bindings ARM: DT updates for v4.4 2015-11-10 15:06:26 -08:00
keys
kvm KVM: arm/arm64: arch_timer: Preserve physical dist. active state on LR.active 2015-11-24 18:07:40 +01:00
linux irqdomain: Allow domain lookup with DOMAIN_BUS_WIRED token 2016-01-26 16:00:14 +01:00
math-emu
media
memory
misc
net net: Propagate lookup failure in l3mdev_get_saddr to caller 2016-01-04 22:58:30 -05:00
pcmcia
ras
rdma IB/mad: Require CM send method for everything except ClassPortInfo 2015-12-08 12:19:11 -05:00
rxrpc
scsi Merge branch 'mkp-fixes' into fixes 2015-12-03 09:32:33 -08:00
soc ARM: SoC driver updates for v4.4 2015-11-10 15:00:03 -08:00
sound Merge remote-tracking branch 'asoc/fix/dapm' into asoc-linus 2016-01-05 23:07:32 +00:00
target target: Fix race for SCF_COMPARE_AND_WRITE_POST checking 2015-11-28 19:33:15 -08:00
trace Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2015-11-11 09:03:01 -08:00
uapi Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-01-11 14:39:17 -08:00
video gpu: ipu-v3: drop unused dmfc field from client platform data 2015-11-24 11:30:15 +01:00
xen xen: Add RING_COPY_REQUEST() 2015-12-18 10:00:17 -05:00
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