[v2,05/12] dt-bindings: remoteproc: Add Qualcomm RPM processor/subsystem

Message ID 20230531-rpm-rproc-v2-5-56a4a00c8260@gerhold.net
State New
Headers
Series Add dedicated device tree node for RPM processor/subsystem |

Commit Message

Stephan Gerhold June 8, 2023, 7:10 a.m. UTC
  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>
---
This patch is based on qcom/for-next, since it needs the new
qcom,rpm-master-stats.yaml schema that is only applied there.
---
 .../bindings/remoteproc/qcom,rpm-proc.yaml         | 171 +++++++++++++++++++++
 .../devicetree/bindings/soc/qcom/qcom,smd-rpm.yaml |   6 +-
 .../devicetree/bindings/soc/qcom/qcom,smd.yaml     |   7 +
 3 files changed, 181 insertions(+), 3 deletions(-)
  

Comments

Rob Herring June 8, 2023, 8:27 a.m. UTC | #1
On Thu, 08 Jun 2023 09:10:25 +0200, Stephan Gerhold wrote:
> 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>
> ---
> This patch is based on qcom/for-next, since it needs the new
> qcom,rpm-master-stats.yaml schema that is only applied there.
> ---
>  .../bindings/remoteproc/qcom,rpm-proc.yaml         | 171 +++++++++++++++++++++
>  .../devicetree/bindings/soc/qcom/qcom,smd-rpm.yaml |   6 +-
>  .../devicetree/bindings/soc/qcom/qcom,smd.yaml     |   7 +
>  3 files changed, 181 insertions(+), 3 deletions(-)
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
./Documentation/devicetree/bindings/remoteproc/qcom,rpm-proc.yaml: Unable to find schema file matching $id: http://devicetree.org/schemas/soc/qcom/qcom,rpm-master-stats.yaml

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20230531-rpm-rproc-v2-5-56a4a00c8260@gerhold.net

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.
  
Krzysztof Kozlowski June 10, 2023, 4:43 p.m. UTC | #2
On 08/06/2023 09:10, Stephan Gerhold wrote:
> 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.


Thank you for your patch. There is something to discuss/improve.


> +
> +  smd-edge:
> +    $ref: /schemas/remoteproc/qcom,smd-edge.yaml#
> +    description:
> +      Qualcomm Shared Memory subnode which represents communication edge,
> +      channels and devices related to the RPM subsystem.
> +
> +  glink-rpm:

This should be "glink-edge", to be a bit more generic and match existing
smd-edge.

> +    $ref: /schemas/remoteproc/qcom,glink-rpm-edge.yaml#
> +    description:
> +      Qualcomm G-Link subnode which represents communication edge,
> +      channels and devices related to the RPM subsystem.
> +
> +  interrupt-controller:
> +    type: object
> +    $ref: /schemas/interrupt-controller/qcom,mpm.yaml#
> +    description:
> +      MSM Power Manager (MPM) interrupt controller that monitors interrupts
> +      when the system is asleep.
> +
> +  master-stats:
> +    $ref: /schemas/soc/qcom/qcom,rpm-master-stats.yaml#
> +    description:
> +      Subsystem-level low-power mode statistics provided by RPM.
> +
> +required:
> +  - compatible
> +


Best regards,
Krzysztof
  
Stephan Gerhold June 10, 2023, 4:52 p.m. UTC | #3
On Sat, Jun 10, 2023 at 06:43:17PM +0200, Krzysztof Kozlowski wrote:
> On 08/06/2023 09:10, Stephan Gerhold wrote:
> > 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.
> > +
> > +  smd-edge:
> > +    $ref: /schemas/remoteproc/qcom,smd-edge.yaml#
> > +    description:
> > +      Qualcomm Shared Memory subnode which represents communication edge,
> > +      channels and devices related to the RPM subsystem.
> > +
> > +  glink-rpm:
> 
> This should be "glink-edge", to be a bit more generic and match existing
> smd-edge.
> 

I fully agree and I actually made that change at some point before
sending v1. Unfortunately, it doesn't work: The node name "glink-edge"
is already reserved by qcom,glink-edge.yaml. While it's very similar it
has some subtle differences to glink-rpm-edge.yaml. For example, there
is no qcom,remote-pid in the RPM variant which is required by the normal
glink-edge.

Would "glink-rpm-edge" sound better?

Thanks,
Stephan
  
Krzysztof Kozlowski June 12, 2023, 6:19 p.m. UTC | #4
On 10/06/2023 18:52, Stephan Gerhold wrote:
> On Sat, Jun 10, 2023 at 06:43:17PM +0200, Krzysztof Kozlowski wrote:
>> On 08/06/2023 09:10, Stephan Gerhold wrote:
>>> 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.
>>> +
>>> +  smd-edge:
>>> +    $ref: /schemas/remoteproc/qcom,smd-edge.yaml#
>>> +    description:
>>> +      Qualcomm Shared Memory subnode which represents communication edge,
>>> +      channels and devices related to the RPM subsystem.
>>> +
>>> +  glink-rpm:
>>
>> This should be "glink-edge", to be a bit more generic and match existing
>> smd-edge.
>>
> 
> I fully agree and I actually made that change at some point before
> sending v1. Unfortunately, it doesn't work: The node name "glink-edge"
> is already reserved by qcom,glink-edge.yaml. While it's very similar it
> has some subtle differences to glink-rpm-edge.yaml. For example, there
> is no qcom,remote-pid in the RPM variant which is required by the normal
> glink-edge.

But the other variant has, so they are pretty similar. It could be one
binding or some common part. Anyway we can as well drop the nodename
from the qcom,glink-edge.yaml binding. Anyway the binding is referenced
by each specific remote proc, so this nodename brings nothing.

> Would "glink-rpm-edge" sound better?
> 
> Thanks,
> Stephan
> 

Best regards,
Krzysztof
  

Patch

diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,rpm-proc.yaml b/Documentation/devicetree/bindings/remoteproc/qcom,rpm-proc.yaml
new file mode 100644
index 000000000000..9c016613463f
--- /dev/null
+++ b/Documentation/devicetree/bindings/remoteproc/qcom,rpm-proc.yaml
@@ -0,0 +1,171 @@ 
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/remoteproc/qcom,rpm-proc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm Resource Power Manager (RPM) Processor/Subsystem
+
+maintainers:
+  - Bjorn Andersson <andersson@kernel.org>
+  - Konrad Dybcio <konrad.dybcio@linaro.org>
+  - Stephan Gerhold <stephan@gerhold.net>
+
+description: |
+  Resource Power Manager (RPM) subsystem found in various Qualcomm platforms:
+
+                  +--------------------------------------------+
+                  |       RPM subsystem (qcom,rpm-proc)        |
+                  |                                            |
+            reset | +---------------+     +-----+  +-----+     |
+          --------->|               |     | MPM |  | CPR | ... |
+   IPC interrupts | | ARM Cortex-M3 |---  +-----+  +-----+     |
+  ----------------->|               |  |     |        |        |
+                  | +---------------+  |---------------------- |
+                  | +---------------+  |                       |
+                  | |   Code RAM    |--|  +------------------+ |
+                  | +---------------+  |  |                  | |
+                  | +---------------+  |--|   Message RAM    | |
+                  | |   Data RAM    |--|  |                  | |
+                  | +---------------+  |  +------------------+ |
+                  +--------------------|-----------------------+
+                                       v
+                                      NoC
+
+  The firmware running on the processor inside the RPM subsystem allows each
+  component in the system to vote for state of the system resources, such as
+  clocks, regulators and bus frequencies. It implements multiple separate
+  communication interfaces that are described in subnodes, e.g. SMD and MPM:
+
+             +------------------------------+
+             |        ARM Cortex-M3         |
+             |                              |   +------------------------------+
+             | +--------------------------+ |   |          Message RAM         |
+             | |  RPM firmware            | |   |                              |
+   IPC IRQ 0 | | +----------------------+ | |   | +--------------------------+ |
+  -------------->| SMD server           |<------->| SMD data structures      | |
+             | | | +--------------+     | | |   | | +--------------+         | |
+             | | | | rpm_requests | ... | | |   | | | rpm_requests |   ...   | |
+             | | | +--------------+     | | |   | | +--------------+         | |
+   IPC IRQ 1 | | +----------------------+ | |   | +--------------------------+ |
+  -------------->| MPM virtualization   |<--------| MPM register copy (vMPM) | |
+             | | +----------------------+ | |   | +--------------------------+ |
+             | |           ...      |     | |   |              ...             |
+             | +--------------------|-----+ |   +------------------------------+
+             +----------------------|-------+
+                                    v
+                             +--------------+
+                             | MPM Hardware |
+                             +--------------+
+
+  The services provided by the firmware are only available after the firmware
+  has been loaded and the processor has been released from reset. Usually this
+  happens early in the boot process before the operating system is started.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - qcom,apq8084-rpm-proc
+          - qcom,ipq6018-rpm-proc
+          - qcom,ipq9574-rpm-proc
+          - qcom,mdm9607-rpm-proc
+          - qcom,msm8226-rpm-proc
+          - qcom,msm8610-rpm-proc
+          - qcom,msm8909-rpm-proc
+          - qcom,msm8916-rpm-proc
+          - qcom,msm8917-rpm-proc
+          - qcom,msm8936-rpm-proc
+          - qcom,msm8937-rpm-proc
+          - qcom,msm8952-rpm-proc
+          - qcom,msm8953-rpm-proc
+          - qcom,msm8974-rpm-proc
+          - qcom,msm8976-rpm-proc
+          - qcom,msm8994-rpm-proc
+          - qcom,msm8996-rpm-proc
+          - qcom,msm8998-rpm-proc
+          - qcom,qcm2290-rpm-proc
+          - qcom,qcs404-rpm-proc
+          - qcom,sdm660-rpm-proc
+          - qcom,sm6115-rpm-proc
+          - qcom,sm6125-rpm-proc
+          - qcom,sm6375-rpm-proc
+      - const: qcom,rpm-proc
+
+  smd-edge:
+    $ref: /schemas/remoteproc/qcom,smd-edge.yaml#
+    description:
+      Qualcomm Shared Memory subnode which represents communication edge,
+      channels and devices related to the RPM subsystem.
+
+  glink-rpm:
+    $ref: /schemas/remoteproc/qcom,glink-rpm-edge.yaml#
+    description:
+      Qualcomm G-Link subnode which represents communication edge,
+      channels and devices related to the RPM subsystem.
+
+  interrupt-controller:
+    type: object
+    $ref: /schemas/interrupt-controller/qcom,mpm.yaml#
+    description:
+      MSM Power Manager (MPM) interrupt controller that monitors interrupts
+      when the system is asleep.
+
+  master-stats:
+    $ref: /schemas/soc/qcom/qcom,rpm-master-stats.yaml#
+    description:
+      Subsystem-level low-power mode statistics provided by RPM.
+
+required:
+  - compatible
+
+oneOf:
+  - required:
+      - smd-edge
+  - required:
+      - glink-rpm
+
+additionalProperties: false
+
+examples:
+  # SMD
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    remoteproc {
+      compatible = "qcom,msm8916-rpm-proc", "qcom,rpm-proc";
+
+      smd-edge {
+        interrupts = <GIC_SPI 168 IRQ_TYPE_EDGE_RISING>;
+        qcom,ipc = <&apcs 8 0>;
+        qcom,smd-edge = <15>;
+
+        rpm-requests {
+          compatible = "qcom,rpm-msm8916";
+          qcom,smd-channels = "rpm_requests";
+          /* ... */
+        };
+      };
+    };
+  # GLINK
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    remoteproc {
+      compatible = "qcom,qcm2290-rpm-proc", "qcom,rpm-proc";
+
+      glink-rpm {
+        compatible = "qcom,glink-rpm";
+        interrupts = <GIC_SPI 194 IRQ_TYPE_EDGE_RISING>;
+        qcom,rpm-msg-ram = <&rpm_msg_ram>;
+        mboxes = <&apcs_glb 0>;
+
+        rpm-requests {
+          compatible = "qcom,rpm-qcm2290";
+          qcom,glink-channels = "rpm_requests";
+          /* ... */
+        };
+      };
+    };
diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,smd-rpm.yaml b/Documentation/devicetree/bindings/soc/qcom/qcom,smd-rpm.yaml
index c6930706bfa9..2fa725b8af5d 100644
--- a/Documentation/devicetree/bindings/soc/qcom/qcom,smd-rpm.yaml
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,smd-rpm.yaml
@@ -120,10 +120,10 @@  examples:
     #include <dt-bindings/interrupt-controller/arm-gic.h>
     #include <dt-bindings/interrupt-controller/irq.h>
 
-    smd {
-        compatible = "qcom,smd";
+    remoteproc {
+        compatible = "qcom,msm8916-rpm-proc", "qcom,rpm-proc";
 
-        rpm {
+        smd-edge {
             interrupts = <GIC_SPI 168 IRQ_TYPE_EDGE_RISING>;
             qcom,ipc = <&apcs 8 0>;
             qcom,smd-edge = <15>;
diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,smd.yaml b/Documentation/devicetree/bindings/soc/qcom/qcom,smd.yaml
index 063e595c12f7..4819ce90d206 100644
--- a/Documentation/devicetree/bindings/soc/qcom/qcom,smd.yaml
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,smd.yaml
@@ -15,6 +15,12 @@  description:
   The Qualcomm Shared Memory Driver is a FIFO based communication channel for
   sending data between the various subsystems in Qualcomm platforms.
 
+  Using the top-level SMD node is deprecated. Instead, the SMD edges are defined
+  directly below the device node representing the respective remote subsystem
+  or remote processor.
+
+deprecated: true
+
 properties:
   compatible:
     const: qcom,smd
@@ -37,6 +43,7 @@  examples:
   # The following example represents a smd node, with one edge representing the
   # "rpm" subsystem. For the "rpm" subsystem we have a device tied to the
   # "rpm_request" channel.
+  # NOTE: This is deprecated, represent the RPM using "qcom,rpm-proc" instead.
   - |
     #include <dt-bindings/interrupt-controller/arm-gic.h>