[PATCH 0/5] irqchip: kill the GIC routable domain

Marc Zyngier marc.zyngier at arm.com
Sat Dec 6 05:46:11 PST 2014


After my series removing the gic_arch_extn hack, I figured that the
next step was to expunge the GIC driver of the routable domain horror.

There is a few reasons for this:

- The allocation of interrupts in this domain is fairly similar to
  what we do for MSI (see the GICv2m driver), and stacked domains have
  proved to be a fitting solution.

- The current description in DT is currently entierely inaccurate, and
  as we already broke it for the OMAP WUGEN block, we might as well do
  it again for the TI crossbar.

- The way crossbar, WUGEN and GIC interract is quite complex (this is
  effectively a stack of three interrupt controllers with interesting
  exceptions and braindead routing), and stacked domains are the right
  abstraction for that.

- Other platforms (Freescale Vybrid) are starting to come up with the
  same type of things, and it'd be good to avoid them following the
  same broken model.

- It removes a few lines from the code base so it can't completely be
  a bad idea!

So this patch series does exactly that: make the crossbar a stacked
interrupt controller that only takes care of setting up the routing,
fix the DTs to represent the actual HW, and remove a bit of the
craziness from the GIC code.

As for the previous series:

- I haven't been able to test this at all, I don't have access to the
  HW. TI people, please test and post fixes, as I expect I introduced
  a few bugs.

- This actively *breaks* existing setups. If you boot a new kernel
  with an old DT, interrupt routing *will* be broken. Old kernels on a
  new DT won't boot either! You've been warned. This really outline
  the necessity of actually describing the HW in device trees...

As for the patches, they are on top of 3.18-rc7 + tip/irq/irqdomain-arm +
the gic_arch_extn removal series.

I've pushed the code to:
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git irq/die-gic-arch-extn-die-die-die

Comments welcome,

	 M.

Marc Zyngier (5):
  genirq: Add irqchip_set_wake_parent
  irqchip: crossbar: convert dra7 crossbar to stacked domains
  DT: update ti,irq-crossbar binding
  irqchip: GIC: get rid of routable domain
  DT: arm,gic: kill arm,routable-irqs

 Documentation/devicetree/bindings/arm/gic.txt      |   6 -
 .../devicetree/bindings/arm/omap/crossbar.txt      |  18 +-
 arch/arm/boot/dts/dra7.dtsi                        |  10 +-
 arch/arm/boot/dts/dra72x.dtsi                      |   3 +-
 arch/arm/boot/dts/dra74x.dtsi                      |   5 +-
 arch/arm/mach-omap2/omap4-common.c                 |   4 -
 drivers/irqchip/irq-crossbar.c                     | 202 ++++++++++++---------
 drivers/irqchip/irq-gic.c                          |  59 +-----
 include/linux/irq.h                                |   1 +
 include/linux/irqchip/arm-gic.h                    |   6 -
 include/linux/irqchip/irq-crossbar.h               |  11 --
 kernel/irq/chip.c                                  |  16 ++
 12 files changed, 153 insertions(+), 188 deletions(-)
 delete mode 100644 include/linux/irqchip/irq-crossbar.h

-- 
2.1.3




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