[PATCH v7 08/14] dt-bindings: irqchip: Introduce TISCI Interrupt router bindings

Lokesh Vutla
2019-04-20T10:09:44Z

Add the DT binding documentation for Interrupt router driver.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
---
Changes since v6:
- None.

New firmware is bound to release this month end. When released, Ill repost
with interrupt cells as 2.

.../interrupt-controller/ti,sci-intr.txt | 84 +++++++++++++++++++
MAINTAINERS | 1 +
2 files changed, 85 insertions(+)
create mode 100644 Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt

diff --git a/Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt b/Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
new file mode 100644
index 000000000000..952a74609367
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
@@ -0,0 +1,84 @@
+Texas Instruments K3 Interrupt Router
+=====================================
+
+The Interrupt Router (INTR) module provides a mechanism to mux M
+interrupt inputs to N interrupt outputs, where all M inputs are selectable
+to be driven per N output. An Interrupt Router can either handle edge triggered
+or level triggered interrupts and that is fixed in hardware.
+
+ Interrupt Router
+ +----------------------+
+ | Inputs Outputs |
+ +-------+ | +------+ +-----+ |
+ | GPIO |----------->| | irq0 | | 0 | | Host IRQ
+ +-------+ | +------+ +-----+ | controller
+ | . . | +-------+
+ +-------+ | . . |----->| IRQ |
+ | INTA |----------->| . . | +-------+
+ +-------+ | . +-----+ |
+ | +------+ | N | |
+ | | irqM | +-----+ |
+ | +------+ |
+ | |
+ +----------------------+
+
+There is one register per output (MUXCNTL_N) that controls the selection.
+Configuration of these MUXCNTL_N registers is done by a system controller
+(like the Device Memory and Security Controller on K3 AM654 SoC). System
+controller will keep track of the used and unused registers within the Router.
+Driver should request the system controller to get the range of GIC IRQs
+assigned to the requesting hosts. It is the drivers responsibility to keep
+track of Host IRQs.
+
+Communication between the host processor running an OS and the system
+controller happens through a protocol called TI System Control Interface
+(TISCI protocol). For more details refer:
+Documentation/devicetree/bindings/arm/keystone/ti,sci.txt
+
+TISCI Interrupt Router Node:
+----------------------------
+Required Properties:
+- compatible: Must be "ti,sci-intr".
+- ti,intr-trigger-type: Should be one of the following:
+ 1: If intr supports edge triggered interrupts.
+ 4: If intr supports level triggered interrupts.
+- interrupt-controller: Identifies the node as an interrupt controller
+- #interrupt-cells: Specifies the number of cells needed to encode an
+ interrupt source. The value should be 3.
+ First cell should contain the TISCI device ID of source
+ Second cell should contain the interrupt source offset
+ within the device.
+ Third cell should be 1 if the irq is coming from the
+ interrupt aggregator else 0.
+- ti,sci: Phandle to TI-SCI compatible System controller node.
+- ti,sci-dst-id: TISCI device ID of the destination IRQ controller.
+- ti,sci-rm-range-girq: Array of TISCI subtype ids representing the host irqs
+ assigned to this interrupt router. Each subtype id
+ corresponds to a range of host irqs.
+
+For more details on TISCI IRQ resource management refer:
+http://downloads.ti.com/tisci/esd/latest/2_tisci_msgs/rm/rm_irq.html
+
+Example:
+--------
+The following example demonstrates both interrupt router node and the consumer
+node(main gpio) on the AM654 SoC:
+
+main_intr: interrupt-controller0 {
+ compatible = "ti,sci-intr";
+ ti,intr-trigger-type = <1>;
+ interrupt-controller;
+ interrupt-parent = <&gic500>;
+ #interrupt-cells = <3>;
+ ti,sci = <&dmsc>;
+ ti,sci-dst-id = <56>;
+ ti,sci-rm-range-girq = <0x1>;
+};
+
+main_gpio0: gpio@600000 {
+ ...
+ interrupt-parent = <&main_intr>;
+ interrupts = <57 256 0>, <57 257 0>, <57 258 0>,
+ <57 259 0>, <57 260 0>, <57 261 0>;
+ ...
+};
diff --git a/MAINTAINERS b/MAINTAINERS
index 3671fdea5010..b40762656a6d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15349,6 +15349,7 @@ F: Documentation/devicetree/bindings/reset/ti,sci-reset.txt
F: Documentation/devicetree/bindings/clock/ti,sci-clk.txt
F: drivers/clk/keystone/sci-clk.c
F: drivers/reset/reset-ti-sci.c
+F: Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt

Texas Instruments ASoC drivers
M: Peter Ujfalusi <peter.ujfalusi@ti.com>
--
2.21.0