Re: [PATCH v2 2/3] dt-bindings: arm: Convert CoreSight bindings to DT schema

From: Rob Herring
Date: Mon Jun 27 2022 - 16:11:22 EST


On Mon, Jun 20, 2022 at 06:17:20PM +0100, Suzuki K Poulose wrote:
> Hi Rob
>
> A big Thank You for the effort ! A minor comment below.
>
> On 03/06/2022 02:19, Rob Herring wrote:
> > Each CoreSight component has slightly different requirements and
> > nothing applies to every component, so each CoreSight component has its
> > own schema document.
> >
> > Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> > --
> > v2:
> > - Add missing arm,coresight-dynamic-replicator.yaml and
> > arm,coresight-static-funnel.yaml
> > - Update MAINTAINERS
> > - Fix coresight.txt references
> > - Fix double blank line
> > ---
> > .../bindings/arm/arm,coresight-catu.yaml | 101 +++++
> > .../bindings/arm/arm,coresight-cti.yaml | 3 +-
> > .../arm/arm,coresight-dynamic-funnel.yaml | 126 ++++++
> > .../arm/arm,coresight-dynamic-replicator.yaml | 126 ++++++
> > .../bindings/arm/arm,coresight-etb10.yaml | 92 ++++
> > .../bindings/arm/arm,coresight-etm.yaml | 156 +++++++
> > .../arm/arm,coresight-static-funnel.yaml | 89 ++++
> > .../arm/arm,coresight-static-replicator.yaml | 90 ++++
> > .../bindings/arm/arm,coresight-stm.yaml | 101 +++++
> > .../bindings/arm/arm,coresight-tmc.yaml | 131 ++++++
> > .../bindings/arm/arm,coresight-tpiu.yaml | 91 ++++
> > .../arm/arm,embedded-trace-extension.yaml | 1 -
> > .../devicetree/bindings/arm/coresight.txt | 402 ------------------
> > Documentation/trace/coresight/coresight.rst | 2 +-
> > MAINTAINERS | 3 +-
> > 15 files changed, 1106 insertions(+), 408 deletions(-)
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-catu.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-dynamic-funnel.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-dynamic-replicator.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-etb10.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-static-funnel.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml
> > create mode 100644 Documentation/devicetree/bindings/arm/arm,coresight-tpiu.yaml
> > delete mode 100644 Documentation/devicetree/bindings/arm/coresight.txt
> >
>
> ...
>
> > diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml
> > new file mode 100644
> > index 000000000000..e0377ce48537
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml
> > @@ -0,0 +1,156 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/arm/arm,coresight-etm.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Arm CoreSight Embedded Trace MacroCell
> > +
> > +maintainers:
> > + - Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > + - Mike Leach <mike.leach@xxxxxxxxxx>
> > + - Leo Yan <leo.yan@xxxxxxxxxx>
> > + - Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> > +
> > +description: |
> > + CoreSight components are compliant with the ARM CoreSight architecture
> > + specification and can be connected in various topologies to suit a particular
> > + SoCs tracing needs. These trace components can generally be classified as
> > + sinks, links and sources. Trace data produced by one or more sources flows
> > + through the intermediate links connecting the source to the currently selected
> > + sink.
> > +
> > + The Embedded Trace Macrocell (ETM) is a real-time trace module providing
> > + instruction and data tracing of a processor.
> > +
> > +select:
> > + properties:
> > + compatible:
> > + contains:
> > + enum:
> > + - arm,coresight-etm3x
> > + - arm,coresight-etm4x
> > + - arm,coresight-etm4x-sysreg
> > + required:
> > + - compatible
> > +
> > +allOf:
> > + - if:
> > + not:
> > + properties:
> > + compatible:
> > + contains:
> > + const: arm,coresight-etm4x-sysreg
> > + then:
> > + $ref: /schemas/arm/primecell.yaml#
> > + required:
> > + - reg


^^^^

> > +
> > +properties:
> > + compatible:
> > + oneOf:
> > + - description:
> > + Embedded Trace Macrocell with memory mapped access.
> > + items:
> > + - enum:
> > + - arm,coresight-etm3x
> > + - arm,coresight-etm4x
> > + - const: arm,primecell
> > + - description:
> > + Embedded Trace Macrocell (version 4.x), with system register access only
> > + const: arm,coresight-etm4x-sysreg
> > +
> > + reg:
> > + maxItems: 1
>
> The register field is mandatory for everything, except
> arm,coresight-etm4x-sysreg. Is there a way to enforce that
> selectively for the others ?

Yes, that's what it is doing up above that I flagged.


> > + clocks:
> > + minItems: 1
> > + maxItems: 2
> > +
> > + clock-names:
> > + minItems: 1
> > + items:
> > + - const: apb_pclk
> > + - const: atclk
> > +
> > + arm,coresight-loses-context-with-cpu:
> > + type: boolean
> > + description:
> > + Indicates that the hardware will lose register context on CPU power down
> > + (e.g. CPUIdle). An example of where this may be needed are systems which
> > + contain a coresight component and CPU in the same power domain. When the
> > + CPU powers down the coresight component also powers down and loses its
> > + context.
> > +
> > + arm,cp14:
> > + type: boolean
> > + description:
> > + Must be present if the system accesses ETM/PTM management registers via
> > + co-processor 14.
> > +
> > + qcom,skip-power-up:
> > + type: boolean
> > + description:
> > + Indicates that an implementation can skip powering up the trace unit.
> > + TRCPDCR.PU does not have to be set on Qualcomm Technologies Inc. systems
> > + since ETMs are in the same power domain as their CPU cores. This property
> > + is required to identify such systems with hardware errata where the CPU
> > + watchdog counter is stopped when TRCPDCR.PU is set.
> > +
> > + cpu:
> > + description:
> > + phandle to the cpu this ETM is bound to.
> > + $ref: /schemas/types.yaml#/definitions/phandle
> > +
> > + out-ports:
> > + $ref: /schemas/graph.yaml#/properties/ports
> > + additionalProperties: false
> > +
> > + properties:
> > + port:
> > + description: Output connection from the ETM to CoreSight Trace bus.
> > + $ref: /schemas/graph.yaml#/properties/port > +
> > +required:
> > + - compatible
> > + - clocks
> > + - clock-names
> > + - cpu
> > + - out-ports
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > + - |
> > + ptm@2201c000 {
> > + compatible = "arm,coresight-etm3x", "arm,primecell";
> > + reg = <0x2201c000 0x1000>;
> > +
> > + cpu = <&cpu0>;
> > + clocks = <&oscclk6a>;
> > + clock-names = "apb_pclk";
> > + out-ports {
> > + port {
> > + ptm0_out_port: endpoint {
> > + remote-endpoint = <&funnel_in_port0>;
> > + };
> > + };
> > + };
> > + };
> > +
> > + ptm@2201d000 {
> > + compatible = "arm,coresight-etm3x", "arm,primecell";
> > + reg = <0x2201d000 0x1000>;
> > +
> > + cpu = <&cpu1>;
> > + clocks = <&oscclk6a>;
> > + clock-names = "apb_pclk";
> > + out-ports {
> > + port {
> > + ptm1_out_port: endpoint {
> > + remote-endpoint = <&funnel_in_port1>;
> > + };
> > + };
> > + };
> > + };
> > +...
> > diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-static-funnel.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-static-funnel.yaml
> > new file mode 100644
> > index 000000000000..b9da30ab9ccd
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/arm,coresight-static-funnel.yaml
> > @@ -0,0 +1,89 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/arm/arm,coresight-static-funnel.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
>
> ...
>
> > + - compatible
> > + - in-ports
> > + - out-ports
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > + - |
> > + funnel {
> > + /* non-configurable replicators don't show up on the
> > + * AMBA bus. As such no need to add "arm,primecell".
> > + */
>
> minor nit. Comment styling.
>
> > + compatible = "arm,coresight-static-funnel";
>
> ...
>
> > diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml
> > new file mode 100644
> > index 000000000000..66ee97370fb2
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml
> > @@ -0,0 +1,90 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/arm/arm,coresight-static-replicator.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Arm CoreSight Static Trace Bus Replicator
>
> ...
>
> > +additionalProperties: false
> > +
> > +examples:
> > + - |
> > + replicator {
> > + /* non-configurable replicators don't show up on the
> > + * AMBA bus. As such no need to add "arm,primecell".
> > + */
>
> same as above.
>
> > + compatible = "arm,coresight-static-replicator";
> > +
> > + out-ports {
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + /* replicator output ports */
> > + port@0 {
> > + reg = <0>;
> > + replicator_out_port0: endpoint {
> > + remote-endpoint = <&etb_in_port>;
> > + };
> > + };
> > +
> > + port@1 {
> > + reg = <1>;
> > + replicator_out_port1: endpoint {
> > + remote-endpoint = <&tpiu_in_port>;
> > + };
> > + };
> > + };
> > +
> > + in-ports {
> > + port {
> > + replicator_in_port0: endpoint {
> > + remote-endpoint = <&funnel_out_port0>;
> > + };
> > + };
> > + };
> > + };
> > +...
> > diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml
> > new file mode 100644
> > index 000000000000..905008faa012
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml
> > @@ -0,0 +1,101 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/arm/arm,coresight-stm.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Arm CoreSight System Trace MacroCell
> > +
> > +maintainers:
> > + - Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > + - Mike Leach <mike.leach@xxxxxxxxxx>
> > + - Leo Yan <leo.yan@xxxxxxxxxx>
> > + - Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> > +
> > +description: |
> > + CoreSight components are compliant with the ARM CoreSight architecture
> > + specification and can be connected in various topologies to suit a particular
> > + SoCs tracing needs. These trace components can generally be classified as
> > + sinks, links and sources. Trace data produced by one or more sources flows
> > + through the intermediate links connecting the source to the currently selected
> > + sink.
> > +
> > + The STM is a trace source that is integrated into a CoreSight system, designed
> > + primarily for high-bandwidth trace of instrumentation embedded into software.
> > + This instrumentation is made up of memory-mapped writes to the STM Advanced
> > + eXtensible Interface (AXI) slave, which carry information about the behavior
> > + of the software.
> > +
> > +select:
> > + properties:
> > + compatible:
> > + contains:
> > + const: arm,coresight-stm
> > + required:
> > + - compatible
> > +
> > +allOf:
> > + - $ref: /schemas/arm/primecell.yaml#
> > +
> > +properties:
> > + compatible:
> > + items:
> > + - const: arm,coresight-stm
> > + - const: arm,primecell
> > +
> > + reg:
> > + maxItems: 2
>
> stm-stimulus-base is mandatory for stm. So I believe, we should add
>
> minItems: 2
> above ?

That's the default if not explicit.

Rob