1# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
2# Copyright 2019 Linaro Ltd.
3%YAML 1.2
4---
5$id: http://devicetree.org/schemas/arm/arm,coresight-cti.yaml#
6$schema: http://devicetree.org/meta-schemas/core.yaml#
7
8title: ARM Coresight Cross Trigger Interface (CTI) device.
9
10description: |
11  The CoreSight Embedded Cross Trigger (ECT) consists of CTI devices connected
12  to one or more CoreSight components and/or a CPU, with CTIs interconnected in
13  a star topology via the Cross Trigger Matrix (CTM), which is not programmable.
14  The ECT components are not part of the trace generation data path and are thus
15  not part of the CoreSight graph.
16
17  The CTI component properties define the connections between the individual
18  CTI and the components it is directly connected to, consisting of input and
19  output hardware trigger signals. CTIs can have a maximum number of input and
20  output hardware trigger signals (8 each for v1 CTI, 32 each for v2 CTI). The
21  number is defined at design time, the maximum of each defined in the DEVID
22  register.
23
24  CTIs are interconnected in a star topology via the CTM, using a number of
25  programmable channels, usually 4, but again implementation defined and
26  described in the DEVID register. The star topology is not required to be
27  described in the bindings as the actual connections are software
28  programmable.
29
30  In general the connections between CTI and components via the trigger signals
31  are implementation defined, except when the CTI is connected to an ARM v8
32  architecture core and optional ETM.
33
34  In this case the ARM v8 architecture defines the required signal connections
35  between CTI and the CPU core and ETM if present. In the case of a v8
36  architecturally connected CTI an additional compatible string is used to
37  indicate this feature (arm,coresight-cti-v8-arch).
38
39  When CTI trigger connection information is unavailable then a minimal driver
40  binding can be declared with no explicit trigger signals. This will result
41  the driver detecting the maximum available triggers and channels from the
42  DEVID register and make them all available for use as a single default
43  connection. Any user / client application will require additional information
44  on the connections between the CTI and other components for correct operation.
45  This information might be found by enabling the Integration Test registers in
46  the driver (set CONFIG_CORESIGHT_CTI_INTEGRATION_TEST in Kernel
47  configuration). These registers may be used to explore the trigger connections
48  between CTI and other CoreSight components.
49
50  Certain triggers between CoreSight devices and the CTI have specific types
51  and usages. These can be defined along with the signal indexes with the
52  constants defined in <dt-bindings/arm/coresight-cti-dt.h>
53
54  For example a CTI connected to a core will usually have a DBGREQ signal. This
55  is defined in the binding as type PE_EDBGREQ. These types will appear in an
56  optional array alongside the signal indexes. Omitting types will default all
57  signals to GEN_IO.
58
59  Note that some hardware trigger signals can be connected to non-CoreSight
60  components (e.g. UART etc) depending on hardware implementation.
61
62maintainers:
63  - Mike Leach <mike.leach@linaro.org>
64
65allOf:
66  - $ref: /schemas/arm/primecell.yaml#
67
68# Need a custom select here or 'arm,primecell' will match on lots of nodes
69select:
70  properties:
71    compatible:
72      contains:
73        enum:
74          - arm,coresight-cti
75  required:
76    - compatible
77
78properties:
79  $nodename:
80    pattern: "^cti(@[0-9a-f]+)$"
81  compatible:
82    oneOf:
83      - items:
84          - const: arm,coresight-cti
85          - const: arm,primecell
86      - items:
87          - const: arm,coresight-cti-v8-arch
88          - const: arm,coresight-cti
89          - const: arm,primecell
90
91  reg:
92    maxItems: 1
93
94  cpu:
95    $ref: /schemas/types.yaml#/definitions/phandle
96    description:
97      Handle to cpu this device is associated with. This must appear in the
98      base cti node if compatible string arm,coresight-cti-v8-arch is used,
99      or may appear in a trig-conns child node when appropriate.
100
101  power-domains:
102    maxItems: 1
103
104  arm,cti-ctm-id:
105    $ref: /schemas/types.yaml#/definitions/uint32
106    description:
107      Defines the CTM this CTI is connected to, in large systems with multiple
108      separate CTI/CTM nets. Typically multi-socket systems where the CTM is
109      propagated between sockets.
110
111  arm,cs-dev-assoc:
112    $ref: /schemas/types.yaml#/definitions/phandle
113    description:
114      defines a phandle reference to an associated CoreSight trace device.
115      When the associated trace device is enabled, then the respective CTI
116      will be enabled. Use in a trig-conns node, or in CTI base node when
117      compatible string arm,coresight-cti-v8-arch used. If the associated
118      device has not been registered then the node name will be stored as
119      the connection name for later resolution. If the associated device is
120      not a CoreSight device or not registered then the node name will remain
121      the connection name and automatic enabling will not occur.
122
123  # size cells and address cells required if trig-conns node present.
124  "#size-cells":
125    const: 0
126
127  "#address-cells":
128    const: 1
129
130patternProperties:
131  '^trig-conns@([0-9]+)$':
132    type: object
133    description:
134      A trigger connections child node which describes the trigger signals
135      between this CTI and another hardware device. This device may be a CPU,
136      CoreSight device, any other hardware device or simple external IO lines.
137      The connection may have both input and output triggers, or only one or the
138      other.
139
140    properties:
141      reg:
142        maxItems: 1
143
144      arm,trig-in-sigs:
145        $ref: /schemas/types.yaml#/definitions/uint32-array
146        minItems: 1
147        maxItems: 32
148        description:
149          List of CTI trigger in signal numbers in use by a trig-conns node.
150
151      arm,trig-in-types:
152        $ref: /schemas/types.yaml#/definitions/uint32-array
153        minItems: 1
154        maxItems: 32
155        description:
156          List of constants representing the types for the CTI trigger in
157          signals. Types in this array match to the corresponding signal in the
158          arm,trig-in-sigs array. If the -types array is smaller, or omitted
159          completely, then the types will default to GEN_IO.
160
161      arm,trig-out-sigs:
162        $ref: /schemas/types.yaml#/definitions/uint32-array
163        minItems: 1
164        maxItems: 32
165        description:
166          List of CTI trigger out signal numbers in use by a trig-conns node.
167
168      arm,trig-out-types:
169        $ref: /schemas/types.yaml#/definitions/uint32-array
170        minItems: 1
171        maxItems: 32
172        description:
173          List of constants representing the types for the CTI trigger out
174          signals. Types in this array match to the corresponding signal
175          in the arm,trig-out-sigs array. If the "-types" array is smaller,
176          or omitted completely, then the types will default to GEN_IO.
177
178      arm,trig-filters:
179        $ref: /schemas/types.yaml#/definitions/uint32-array
180        minItems: 1
181        maxItems: 32
182        description:
183          List of CTI trigger out signals that will be blocked from becoming
184          active, unless filtering is disabled on the driver.
185
186      arm,trig-conn-name:
187        $ref: /schemas/types.yaml#/definitions/string
188        description:
189          Defines a connection name that will be displayed, if the cpu or
190          arm,cs-dev-assoc properties are not being used in this connection.
191          Principle use for CTI that are connected to non-CoreSight devices, or
192          external IO.
193
194    anyOf:
195      - required:
196          - arm,trig-in-sigs
197      - required:
198          - arm,trig-out-sigs
199    oneOf:
200      - required:
201          - arm,trig-conn-name
202      - required:
203          - cpu
204      - required:
205          - arm,cs-dev-assoc
206    required:
207      - reg
208
209required:
210  - compatible
211  - reg
212  - clocks
213  - clock-names
214
215if:
216  properties:
217    compatible:
218      contains:
219        const: arm,coresight-cti-v8-arch
220
221then:
222  required:
223    - cpu
224
225unevaluatedProperties: false
226
227examples:
228  # minimum CTI definition. DEVID register used to set number of triggers.
229  - |
230    cti@20020000 {
231      compatible = "arm,coresight-cti", "arm,primecell";
232      reg = <0x20020000 0x1000>;
233
234      clocks = <&soc_smc50mhz>;
235      clock-names = "apb_pclk";
236    };
237  #  v8 architecturally defined CTI - CPU + ETM connections generated by the
238  #  driver according to the v8 architecture specification.
239  - |
240    cti@859000 {
241      compatible = "arm,coresight-cti-v8-arch", "arm,coresight-cti",
242                   "arm,primecell";
243      reg = <0x859000 0x1000>;
244
245      clocks = <&soc_smc50mhz>;
246      clock-names = "apb_pclk";
247
248      cpu = <&CPU1>;
249      arm,cs-dev-assoc = <&etm1>;
250    };
251  # Implementation defined CTI - CPU + ETM connections explicitly defined..
252  # Shows use of type constants from dt-bindings/arm/coresight-cti-dt.h
253  # #size-cells and #address-cells are required if trig-conns@ nodes present.
254  - |
255    #include <dt-bindings/arm/coresight-cti-dt.h>
256
257    cti@858000 {
258      compatible = "arm,coresight-cti", "arm,primecell";
259      reg = <0x858000 0x1000>;
260
261      clocks = <&soc_smc50mhz>;
262      clock-names = "apb_pclk";
263
264      arm,cti-ctm-id = <1>;
265
266      #address-cells = <1>;
267      #size-cells = <0>;
268
269      trig-conns@0 {
270            reg = <0>;
271            arm,trig-in-sigs = <4 5 6 7>;
272            arm,trig-in-types = <ETM_EXTOUT
273                                 ETM_EXTOUT
274                                 ETM_EXTOUT
275                                 ETM_EXTOUT>;
276            arm,trig-out-sigs = <4 5 6 7>;
277            arm,trig-out-types = <ETM_EXTIN
278                                  ETM_EXTIN
279                                  ETM_EXTIN
280                                  ETM_EXTIN>;
281            arm,cs-dev-assoc = <&etm0>;
282      };
283
284      trig-conns@1 {
285            reg = <1>;
286            cpu = <&CPU0>;
287            arm,trig-in-sigs = <0 1>;
288            arm,trig-in-types = <PE_DBGTRIGGER
289                                 PE_PMUIRQ>;
290            arm,trig-out-sigs = <0 1 2 >;
291            arm,trig-out-types = <PE_EDBGREQ
292                                  PE_DBGRESTART
293                                  PE_CTIIRQ>;
294
295            arm,trig-filters = <0>;
296      };
297    };
298  # Implementation defined CTI - non CoreSight component connections.
299  - |
300    cti@20110000 {
301      compatible = "arm,coresight-cti", "arm,primecell";
302      reg = <0x20110000 0x1000>;
303
304      clocks = <&soc_smc50mhz>;
305      clock-names = "apb_pclk";
306
307      #address-cells = <1>;
308      #size-cells = <0>;
309
310      trig-conns@0 {
311        reg = <0>;
312        arm,trig-in-sigs = <0>;
313        arm,trig-in-types = <GEN_INTREQ>;
314        arm,trig-out-sigs = <0>;
315        arm,trig-out-types = <GEN_HALTREQ>;
316        arm,trig-conn-name = "sys_profiler";
317      };
318
319      trig-conns@1 {
320        reg = <1>;
321        arm,trig-out-sigs = <2 3>;
322        arm,trig-out-types = <GEN_HALTREQ GEN_RESTARTREQ>;
323        arm,trig-conn-name = "watchdog";
324      };
325
326      trig-conns@2 {
327        reg = <2>;
328        arm,trig-in-sigs = <1 6>;
329        arm,trig-in-types = <GEN_HALTREQ GEN_RESTARTREQ>;
330        arm,trig-conn-name = "g_counter";
331      };
332    };
333
334...
335