dt-bindings: remoteproc: Add Qualcomm RPM processor/subsystem

On Qualcomm platforms, most subsystems (e.g. audio/modem DSP) are
described as remote processors in the device tree, with a dedicated
node where properties and services related to them can be described.

The Resource Power Manager (RPM) is also such a subsystem, with a
remote processor that is running a special firmware. Unfortunately,
the RPM never got a dedicated node representing it properly in the
device tree. Most of the RPM services are described below a top-level
/smd or /rpm-glink node.

However, SMD/GLINK is just one of the communication channels to the RPM
firmware. For example, the MPM interrupt functionality provided by the
RPM does not use SMD/GLINK but writes directly to a special memory
region allocated by the RPM firmware in combination with a mailbox.
Currently there is no good place in the device tree to describe this
functionality. It doesn't belong below SMD/GLINK but it's not an
independent top-level device either.

Introduce a new "qcom,rpm-proc" compatible that allows describing the
RPM as a remote processor/subsystem like all others. The SMD/GLINK node
is moved to a "smd-edge"/"glink-edge" subnode consistent with other
existing bindings. Additional subnodes (e.g. interrupt-controller for
MPM, rpm-master-stats) can be also added there.

Deprecate using the old top-level /smd node since all SMD edges
are now specified as subnodes of the remote processor.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230531-rpm-rproc-v3-6-a07dcdefd918@gerhold.net
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

dt-bindings: remoteproc: qcom,smd-edge: define children

SMD edge contains subnodes representing devices related to the remote
processor. With limietd number of remote processors, there is a limited
set of such devices.

List all of them in smd-edge bindings so schema can strictly check for
subnodes.

Additional benefit is requirement of "qcom,smd-channels" for such
subnodes, because their schema cannot enforce it (few devices like APR
or FastRPC can be part of either SMD or GLINK edge).

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220909125403.803158-8-krzysztof.kozlowski@linaro.org
Signed-off-by: Rob Herring <robh@kernel.org>

dt-bindings: soc: qcom: smd: restrict child name to smd-edge

Child node of SMD must be either smd-edge or rpm, so the pattern can be
narrowed.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220909125403.803158-7-krzysztof.kozlowski@linaro.org
Signed-off-by: Rob Herring <robh@kernel.org>

dt-bindings: soc: qcom: smd: reference SMD edge schema

The child node of smd is an SMD edge representing remote subsystem.
Bring back missing reference from previously sent patch (disappeared
when applying).

Link: https://lore.kernel.org/r/20220517070113.18023-9-krzysztof.kozlowski@linaro.org
Fixes: 385fad1303af ("dt-bindings: remoteproc: qcom,smd-edge: define re-usable schema for smd-edge")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220723082358.39544-1-krzysztof.kozlowski@linaro.org

dt-bindings: remoteproc: qcom,smd-edge: define re-usable schema for smd-edge

'smd-edge' property appears in multiple bindings, so split it into one
place which can be re-used. This reduces code duplication and adds
strict schema matching for smd-edge nodes (instead of just
"type:object").

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220517070113.18023-9-krzysztof.kozlowski@linaro.org

dt-bindings: soc: qcom,smd: do not use pattern for simple rpm-requests string

patternProperties should not be used for properties with a simple string
as name:

Documentation/devicetree/bindings/soc/qcom/qcom,smd.yaml: patternProperties:^(.*-edge|rpm)$:patternProperties:
'^rpm-requests$' should not be valid under {'pattern': '^\\^[a-zA-Z0-9,\\-._#]+\\$$'}

Fixes: 375eed5f51a8 ("dt-bindings: soc: qcom,smd: convert to dtschema")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220524070408.39505-1-krzysztof.kozlowski@linaro.org

dt-bindings: soc: qcom,smd: convert to dtschema

Convert the Qualcomm Shared Memory Driver bindings to DT Schema.

Changes against original bindings: enforce only specific names of child
nodes, instead of any names.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220401201035.189106-9-krzysztof.kozlowski@linaro.org