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authorMichal Marek <mmarek@suse.cz>2013-02-25 21:50:05 +0100
committerMichal Marek <mmarek@suse.cz>2013-02-25 21:51:57 +0100
commite3900e74f26fc924c8e9e2a922bd40369b0bb517 (patch)
tree6e868575d346032ba9408f350c6e5369e0e52b0d /Documentation/devicetree/bindings/arm/spear
parent62dc989921df2a98d1a73aacd085abe941cb9828 (diff)
parent02f3e53a131c8aa3fe3c954058f1add5beeae621 (diff)
Merge branch 'kbuild/rc-fixes' into kbuild/kconfig
There is one kconfig fix in the rc-fixes branch that I forgot to submit for 3.8, so let's add it to the kconfig branch for 3.9-rc1.
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+* SPEAr Shared IRQ layer (shirq)
+
+SPEAr3xx architecture includes shared/multiplexed irqs for certain set
+of devices. The multiplexor provides a single interrupt to parent
+interrupt controller (VIC) on behalf of a group of devices.
+
+There can be multiple groups available on SPEAr3xx variants but not
+exceeding 4. The number of devices in a group can differ, further they
+may share same set of status/mask registers spanning across different
+bit masks. Also in some cases the group may not have enable or other
+registers. This makes software little complex.
+
+A single node in the device tree is used to describe the shared
+interrupt multiplexor (one node for all groups). A group in the
+interrupt controller shares config/control registers with other groups.
+For example, a 32-bit interrupt enable/disable config register can
+accommodate upto 4 interrupt groups.
+
+Required properties:
+ - compatible: should be, either of
+ - "st,spear300-shirq"
+ - "st,spear310-shirq"
+ - "st,spear320-shirq"
+ - interrupt-controller: Identifies the node as an interrupt controller.
+ - #interrupt-cells: should be <1> which basically contains the offset
+ (starting from 0) of interrupts for all the groups.
+ - reg: Base address and size of shirq registers.
+ - interrupts: The list of interrupts generated by the groups which are
+ then connected to a parent interrupt controller. Each group is
+ associated with one of the interrupts, hence number of interrupts (to
+ parent) is equal to number of groups. The format of the interrupt
+ specifier depends in the interrupt parent controller.
+
+ Optional properties:
+ - interrupt-parent: pHandle of the parent interrupt controller, if not
+ inherited from the parent node.
+
+Example:
+
+The following is an example from the SPEAr320 SoC dtsi file.
+
+shirq: interrupt-controller@0xb3000000 {
+ compatible = "st,spear320-shirq";
+ reg = <0xb3000000 0x1000>;
+ interrupts = <28 29 30 1>;
+ #interrupt-cells = <1>;
+ interrupt-controller;
+};