dt-bindings: arm: Adds CoreSight CTI hardware definitions

Adds new coresight-cti.yaml file describing the bindings required to define
CTI in the device trees.

Adds an include file to dt-bindings/arm to define constants describing
common signal functionality used in CoreSight and generic usage.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200320165303.13681-6-mathieu.poirier@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/arm/coresight-cti.yaml

+# 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";
+      };
+    };
+
+...

Documentation/devicetree/bindings/arm/coresight.txt

@@ -45,6 +45,10 @@ its hardware characteristcs.
 		- Coresight Address Translation Unit (CATU)
 			"arm,coresight-catu", "arm,primecell";
 
+		- Coresight Cross Trigger Interface (CTI):
+			"arm,coresight-cti", "arm,primecell";
+			See coresight-cti.yaml for full CTI definitions.
+
 	* reg: physical base address and length of the register
 	  set(s) of the component.
 
@@ -72,6 +76,9 @@ its hardware characteristcs.
 	* reg-names: the only acceptable values are "stm-base" and
 	  "stm-stimulus-base", each corresponding to the areas defined in "reg".
 
+* Required properties for Coresight Cross Trigger Interface (CTI)
+	See coresight-cti.yaml for full CTI definitions.
+
 * Required properties for devices that don't show up on the AMBA bus, such as
   non-configurable replicators and non-configurable funnels:
 

MAINTAINERS

@@ -1679,9 +1679,11 @@ R:	Suzuki K Poulose <suzuki.poulose@arm.com>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 F:	drivers/hwtracing/coresight/*
+F:	include/dt-bindings/arm/coresight-cti-dt.h
 F:	Documentation/trace/coresight/*
 F:	Documentation/devicetree/bindings/arm/coresight.txt
 F:	Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt
+F:	Documentation/devicetree/bindings/arm/coresight-cti.yaml
 F:	Documentation/ABI/testing/sysfs-bus-coresight-devices-*
 F:	tools/perf/arch/arm/util/pmu.c
 F:	tools/perf/arch/arm/util/auxtrace.c

include/dt-bindings/arm/coresight-cti-dt.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides constants for the defined trigger signal
+ * types on CoreSight CTI.
+ */
+
+#ifndef _DT_BINDINGS_ARM_CORESIGHT_CTI_DT_H
+#define _DT_BINDINGS_ARM_CORESIGHT_CTI_DT_H
+
+#define GEN_IO		0
+#define GEN_INTREQ	1
+#define GEN_INTACK	2
+#define GEN_HALTREQ	3
+#define GEN_RESTARTREQ	4
+#define PE_EDBGREQ	5
+#define PE_DBGRESTART	6
+#define PE_CTIIRQ	7
+#define PE_PMUIRQ	8
+#define PE_DBGTRIGGER	9
+#define ETM_EXTOUT	10
+#define ETM_EXTIN	11
+#define SNK_FULL	12
+#define SNK_ACQCOMP	13
+#define SNK_FLUSHCOMP	14
+#define SNK_FLUSHIN	15
+#define SNK_TRIGIN	16
+#define STM_ASYNCOUT	17
+#define STM_TOUT_SPTE	18
+#define STM_TOUT_SW	19
+#define STM_TOUT_HETE	20
+#define STM_HWEVENT	21
+#define ELA_TSTART	22
+#define ELA_TSTOP	23
+#define ELA_DBGREQ	24
+#define CTI_TRIG_MAX	25
+
+#endif /*_DT_BINDINGS_ARM_CORESIGHT_CTI_DT_H */