--- /dev/null
+# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause
+# Copyright 2019 Linaro Ltd.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/coresight-cti.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ARM Coresight Cross Trigger Interface (CTI) device.
+
+description: |
+ The CoreSight Embedded Cross Trigger (ECT) consists of CTI devices connected
+ to one or more CoreSight components and/or a CPU, with CTIs interconnected in
+ a star topology via the Cross Trigger Matrix (CTM), which is not programmable.
+ The ECT components are not part of the trace generation data path and are thus
+ not part of the CoreSight graph described in the general CoreSight bindings
+ file coresight.txt.
+
+ The CTI component properties define the connections between the individual
+ CTI and the components it is directly connected to, consisting of input and
+ output hardware trigger signals. CTIs can have a maximum number of input and
+ output hardware trigger signals (8 each for v1 CTI, 32 each for v2 CTI). The
+ number is defined at design time, the maximum of each defined in the DEVID
+ register.
+
+ CTIs are interconnected in a star topology via the CTM, using a number of
+ programmable channels, usually 4, but again implementation defined and
+ described in the DEVID register. The star topology is not required to be
+ described in the bindings as the actual connections are software
+ programmable.
+
+ In general the connections between CTI and components via the trigger signals
+ are implementation defined, except when the CTI is connected to an ARM v8
+ architecture core and optional ETM.
+
+ In this case the ARM v8 architecture defines the required signal connections
+ between CTI and the CPU core and ETM if present. In the case of a v8
+ architecturally connected CTI an additional compatible string is used to
+ indicate this feature (arm,coresight-cti-v8-arch).
+
+ When CTI trigger connection information is unavailable then a minimal driver
+ binding can be declared with no explicit trigger signals. This will result
+ the driver detecting the maximum available triggers and channels from the
+ DEVID register and make them all available for use as a single default
+ connection. Any user / client application will require additional information
+ on the connections between the CTI and other components for correct operation.
+ This information might be found by enabling the Integration Test registers in
+ the driver (set CONFIG_CORESIGHT_CTI_INTEGRATION_TEST in Kernel
+ configuration). These registers may be used to explore the trigger connections
+ between CTI and other CoreSight components.
+
+ Certain triggers between CoreSight devices and the CTI have specific types
+ and usages. These can be defined along with the signal indexes with the
+ constants defined in <dt-bindings/arm/coresight-cti-dt.h>
+
+ For example a CTI connected to a core will usually have a DBGREQ signal. This
+ is defined in the binding as type PE_EDBGREQ. These types will appear in an
+ optional array alongside the signal indexes. Omitting types will default all
+ signals to GEN_IO.
+
+ Note that some hardware trigger signals can be connected to non-CoreSight
+ components (e.g. UART etc) depending on hardware implementation.
+
+maintainers:
+ - Mike Leach <mike.leach@linaro.org>
+
+allOf:
+ - $ref: /schemas/arm/primecell.yaml#
+
+# Need a custom select here or 'arm,primecell' will match on lots of nodes
+select:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - arm,coresight-cti
+ required:
+ - compatible
+
+properties:
+ $nodename:
+ pattern: "^cti(@[0-9a-f]+)$"
+ compatible:
+ oneOf:
+ - items:
+ - const: arm,coresight-cti
+ - const: arm,primecell
+ - items:
+ - const: arm,coresight-cti-v8-arch
+ - const: arm,coresight-cti
+ - const: arm,primecell
+
+ reg:
+ maxItems: 1
+
+ cpu:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ Handle to cpu this device is associated with. This must appear in the
+ base cti node if compatible string arm,coresight-cti-v8-arch is used,
+ or may appear in a trig-conns child node when appropriate.
+
+ arm,cti-ctm-id:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ Defines the CTM this CTI is connected to, in large systems with multiple
+ separate CTI/CTM nets. Typically multi-socket systems where the CTM is
+ propagated between sockets.
+
+ arm,cs-dev-assoc:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ defines a phandle reference to an associated CoreSight trace device.
+ When the associated trace device is enabled, then the respective CTI
+ will be enabled. Use in a trig-conns node, or in CTI base node when
+ compatible string arm,coresight-cti-v8-arch used. If the associated
+ device has not been registered then the node name will be stored as
+ the connection name for later resolution. If the associated device is
+ not a CoreSight device or not registered then the node name will remain
+ the connection name and automatic enabling will not occur.
+
+ # size cells and address cells required if trig-conns node present.
+ "#size-cells":
+ const: 0
+
+ "#address-cells":
+ const: 1
+
+patternProperties:
+ '^trig-conns@([0-9]+)$':
+ type: object
+ description:
+ A trigger connections child node which describes the trigger signals
+ between this CTI and another hardware device. This device may be a CPU,
+ CoreSight device, any other hardware device or simple external IO lines.
+ The connection may have both input and output triggers, or only one or the
+ other.
+
+ properties:
+ reg:
+ maxItems: 1
+
+ arm,trig-in-sigs:
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-array
+ minItems: 1
+ maxItems: 32
+ description:
+ List of CTI trigger in signal numbers in use by a trig-conns node.
+
+ arm,trig-in-types:
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-array
+ minItems: 1
+ maxItems: 32
+ description:
+ List of constants representing the types for the CTI trigger in
+ signals. Types in this array match to the corresponding signal in the
+ arm,trig-in-sigs array. If the -types array is smaller, or omitted
+ completely, then the types will default to GEN_IO.
+
+ arm,trig-out-sigs:
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-array
+ minItems: 1
+ maxItems: 32
+ description:
+ List of CTI trigger out signal numbers in use by a trig-conns node.
+
+ arm,trig-out-types:
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-array
+ minItems: 1
+ maxItems: 32
+ description:
+ List of constants representing the types for the CTI trigger out
+ signals. Types in this array match to the corresponding signal
+ in the arm,trig-out-sigs array. If the "-types" array is smaller,
+ or omitted completely, then the types will default to GEN_IO.
+
+ arm,trig-filters:
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-array
+ minItems: 1
+ maxItems: 32
+ description:
+ List of CTI trigger out signals that will be blocked from becoming
+ active, unless filtering is disabled on the driver.
+
+ arm,trig-conn-name:
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/string
+ description:
+ Defines a connection name that will be displayed, if the cpu or
+ arm,cs-dev-assoc properties are not being used in this connection.
+ Principle use for CTI that are connected to non-CoreSight devices, or
+ external IO.
+
+ anyOf:
+ - required:
+ - arm,trig-in-sigs
+ - required:
+ - arm,trig-out-sigs
+ oneOf:
+ - required:
+ - arm,trig-conn-name
+ - required:
+ - cpu
+ - required:
+ - arm,cs-dev-assoc
+ required:
+ - reg
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - clock-names
+
+if:
+ properties:
+ compatible:
+ contains:
+ const: arm,coresight-cti-v8-arch
+
+then:
+ required:
+ - cpu
+
+examples:
+ # minimum CTI definition. DEVID register used to set number of triggers.
+ - |
+ cti@20020000 {
+ compatible = "arm,coresight-cti", "arm,primecell";
+ reg = <0x20020000 0x1000>;
+
+ clocks = <&soc_smc50mhz>;
+ clock-names = "apb_pclk";
+ };
+ # v8 architecturally defined CTI - CPU + ETM connections generated by the
+ # driver according to the v8 architecture specification.
+ - |
+ cti@859000 {
+ compatible = "arm,coresight-cti-v8-arch", "arm,coresight-cti",
+ "arm,primecell";
+ reg = <0x859000 0x1000>;
+
+ clocks = <&soc_smc50mhz>;
+ clock-names = "apb_pclk";
+
+ cpu = <&CPU1>;
+ arm,cs-dev-assoc = <&etm1>;
+ };
+ # Implementation defined CTI - CPU + ETM connections explicitly defined..
+ # Shows use of type constants from dt-bindings/arm/coresight-cti-dt.h
+ # #size-cells and #address-cells are required if trig-conns@ nodes present.
+ - |
+ #include <dt-bindings/arm/coresight-cti-dt.h>
+
+ cti@858000 {
+ compatible = "arm,coresight-cti", "arm,primecell";
+ reg = <0x858000 0x1000>;
+
+ clocks = <&soc_smc50mhz>;
+ clock-names = "apb_pclk";
+
+ arm,cti-ctm-id = <1>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ trig-conns@0 {
+ reg = <0>;
+ arm,trig-in-sigs = <4 5 6 7>;
+ arm,trig-in-types = <ETM_EXTOUT
+ ETM_EXTOUT
+ ETM_EXTOUT
+ ETM_EXTOUT>;
+ arm,trig-out-sigs = <4 5 6 7>;
+ arm,trig-out-types = <ETM_EXTIN
+ ETM_EXTIN
+ ETM_EXTIN
+ ETM_EXTIN>;
+ arm,cs-dev-assoc = <&etm0>;
+ };
+
+ trig-conns@1 {
+ reg = <1>;
+ cpu = <&CPU0>;
+ arm,trig-in-sigs = <0 1>;
+ arm,trig-in-types = <PE_DBGTRIGGER
+ PE_PMUIRQ>;
+ arm,trig-out-sigs=<0 1 2 >;
+ arm,trig-out-types = <PE_EDBGREQ
+ PE_DBGRESTART
+ PE_CTIIRQ>;
+
+ arm,trig-filters = <0>;
+ };
+ };
+ # Implementation defined CTI - non CoreSight component connections.
+ - |
+ cti@20110000 {
+ compatible = "arm,coresight-cti", "arm,primecell";
+ reg = <0 0x20110000 0 0x1000>;
+
+ clocks = <&soc_smc50mhz>;
+ clock-names = "apb_pclk";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ trig-conns@0 {
+ reg = <0>;
+ arm,trig-in-sigs=<0>;
+ arm,trig-in-types=<GEN_INTREQ>;
+ arm,trig-out-sigs=<0>;
+ arm,trig-out-types=<GEN_HALTREQ>;
+ arm,trig-conn-name = "sys_profiler";
+ };
+
+ trig-conns@1 {
+ reg = <1>;
+ arm,trig-out-sigs=<2 3>;
+ arm,trig-out-types=<GEN_HALTREQ GEN_RESTARTREQ>;
+ arm,trig-conn-name = "watchdog";
+ };
+
+ trig-conns@2 {
+ reg = <2>;
+ arm,trig-in-sigs=<1 6>;
+ arm,trig-in-types=<GEN_HALTREQ GEN_RESTARTREQ>;
+ arm,trig-conn-name = "g_counter";
+ };
+ };
+
+...