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.

@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

Figure 43 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.