[v4,1/2] dt-bindings: arm: optee: add interrupt controller properties
Commit Message
Adds an optional interrupt controller property to optee firmware node
in the DT bindings. Optee driver may embeds an irqchip exposing
OP-TEE interrupt events notified by the TEE world. Optee registers up
to 1 interrupt controller and identifies each line with a line
number from 0 to UINT16_MAX.
The identifiers and meaning of the interrupt line number are specific
to the platform and shall be found in the OP-TEE platform documentation.
In the example shown in optee DT binding documentation, the platform SCMI
device controlled by Linux scmi driver uses optee interrupt irq 5 as
signal to trigger processing of an asynchronous incoming SCMI message
in the scope of a CPU DVFS control. A platform can have several SCMI
channels driven this way. Optee irqs also permit small embedded devices
to share e.g. a gpio expander, a group of wakeup sources, etc... between
OP-TEE world (for sensitive services) and Linux world (for non-sensitive
services). The physical controller is driven from the TEE which exposes
some controls to Linux kernel.
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Sumit Garg <sumit.garg@linaro.org>
Co-developed-by: Pascal Paillet <p.paillet@foss.st.com>
Signed-off-by: Pascal Paillet <p.paillet@foss.st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
---
No changes since v3
Changes since v2:
- Added a sentence on optee irq line number values and meaning, in
DT binding doc and commit message.
- Updated example in DT binding doc from comment, fixed misplaced
interrupt-parent property and removed gic and sram shm nodes.
Changes since v1:
- Added a description to #interrupt-cells property.
- Changed of example. Linux wakeup event was subject to discussion and
i don't know much about input events in Linux. So move to SCMI.
In the example, an SCMI server in OP-TEE world raises optee irq 5
so that Linux scmi optee channel &scmi_cpu_dvfs pushed in the incoming
SCMI message in the scmi device for liekly later processing in threaded
context. The example includes all parties: optee, scmi, sram, gic.
- Obviously rephrased the commit message.
---
.../arm/firmware/linaro,optee-tz.yaml | 38 +++++++++++++++++++
1 file changed, 38 insertions(+)
@@ -40,6 +40,16 @@ properties:
HVC #0, register assignments
register assignments are specified in drivers/tee/optee/optee_smc.h
+ interrupt-controller: true
+
+ "#interrupt-cells":
+ const: 1
+ description: |
+ OP-TEE exposes irq for irp chip controllers from OP-TEE world. Each
+ irq is assigned a single line number identifier used as first argument.
+ Line number identifiers and their meaning shall be found in the OP-TEE
+ firmware platform documentation.
+
required:
- compatible
- method
@@ -64,3 +74,31 @@ examples:
method = "hvc";
};
};
+
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ firmware {
+ optee: optee {
+ compatible = "linaro,optee-tz";
+ method = "smc";
+ interrupt-parent = <&gic>;
+ interrupts = <GIC_SPI 187 IRQ_TYPE_EDGE_RISING>;
+ interrupt-controller;
+ #interrupt-cells = <1>;
+ };
+
+ scmi {
+ compatible = "linaro,scmi-optee";
+ linaro,optee-channel-id = <0>;
+ shmem = <&scmi_shm_tx>, <&scmi_shm_rx>;
+ interrupts-extended = <&optee 5>;
+ interrupt-names = "a2p";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ scmi_cpu_dvfs: protocol@13 {
+ reg = <0x13>;
+ #clock-cells = <1>;
+ };
+ };
+ };