arch: fw: app layer description

Application layer components description in
SOF with Zephyr architecture

Signed-off-by: Michal Wasko <[email protected]>

Author: mwasko

architectures/firmware/sof-zephyr/app_layer/images/app_layer_diagram.pu

@@ -0,0 +1,68 @@
+@startuml
+allowmixing
+
+scale max 1280 width
+
+package "SOF" {
+
+  package "Application layer" as APP_CUSTOMIZATION {
+
+    package "Example Loadable Components" as LOADABLE_COMPONENTS {
+      component "3rd Party Post-Processing" as PROCESSING_3RD_PARTY
+      component "WoV" as WOV_MODULE
+      component "ACA" as ACA_MODULE
+      component "Other modules" as OTHER_MODULES
+
+      PROCESSING_3RD_PARTY -[hidden]right- WOV_MODULE
+      WOV_MODULE -[hidden]right- ACA_MODULE
+      ACA_MODULE -[hidden]right- OTHER_MODULES
+    }
+
+    package "Built-in Components" as BUILTIN_COMPONENTS {
+      component "Copier" as COPIER
+      component "SRC" as SRC
+      component "Mixers" as MIXERS
+      component "History Buffer/KPB" as HISTORY_BUFFER
+      component "Probe" as PROBE
+
+      COPIER -[hidden]right- SRC
+      SRC -[hidden]right- MIXERS
+      MIXERS -[hidden]right- HISTORY_BUFFER
+      HISTORY_BUFFER -[hidden]right- PROBE
+    }
+
+      BUILTIN_COMPONENTS -[hidden]down- LOADABLE_COMPONENTS
+  }
+
+  package "System Services" as SYS_SERVICES {
+
+    interface "System Services" as SS
+
+    package "Media Processing Pipelines Services extension" as KERNEL_EXTENSION {
+        component "Communication" as COMMUNICATION
+        component "Pipelines and Component Infrastructure" as PIPELINE_COMPONENT_INFRASTRUCTURE
+        component "AVS Scheduling" as AVS_SCHEDULERS
+
+        COMMUNICATION -[hidden]right- PIPELINE_COMPONENT_INFRASTRUCTURE
+        PIPELINE_COMPONENT_INFRASTRUCTURE -[hidden]right- AVS_SCHEDULERS
+    }
+
+    package "Zephyr" as ZEPHYR {
+        component "Services" as SERVICES
+    }
+
+    SS -[hidden]down- KERNEL_EXTENSION
+    SS -[hidden]down- ZEPHYR
+
+    KERNEL_EXTENSION -[hidden]right- ZEPHYR
+  }
+
+  APP_CUSTOMIZATION -[hidden]down- SYS_SERVICES
+  BUILTIN_COMPONENTS .down. SS
+  PROCESSING_3RD_PARTY .down. SS
+  WOV_MODULE .down. SS
+  ACA_MODULE .down. SS
+  OTHER_MODULES .down. SS
+}
+
+@enduml

architectures/firmware/sof-zephyr/app_layer/index.rst

@@ -0,0 +1,40 @@
+.. _app_layer:
+
+Application Layer
+#################
+
+Application Layer represents the built-in FW processing components, loadable FW
+components and example templates with application libraries required for
+components integration. Application layer content is assumed to be open source
+and only proprietary 3rd party components should remain private.
+
+.. uml:: images/app_layer_diagram.pu
+   :caption: Application Layer
+
+Components in Application Layer
+*******************************
+
+The built-in components are built together with base firmware and they have
+direct access to all firmware drivers and service APIs. When built-in module
+is enabled in configuration, it is guaranteed to exist in firmware binary.
+
+The loadable components are built separately from base firmware and they are
+loaded dynamically as a separate binary, depending on the host audio
+configuration.
+
+All the application layer components access base firmware services via System
+Services ABI.
+
+**NOTE:** The built-in components are utility components provided by base
+firmware/kernel.
+
+Examples of built-in components:
+
+* Audio built-in components: Copiers, Mixers, Volume, SRC, etc.
+
+Probe
+=====
+
+The probe module is special module in FW infrastructure that allows to inject
+or extract data from a specified probe point. The traditional client
+platforms use HDA DMAs to transfer data in and out of such module.

architectures/firmware/sof-zephyr/index.rst

@@ -7,3 +7,4 @@ SOF with Zephyr Architecture
    :maxdepth: 1
 
    overview
+   app_layer/index