ODP specification ================= ODP specification consists of several types of files, which together provide full list of types, values and functions that ODP implementation MUST provide. ODP API specification --------------------- These are the files from `include/odp/api/spec` directory. They specify a set of function prototypes, types, type names, enumerations etc that MUST be provided by ODP implementation. Doxygen comments inside these files document requirements for ABI interface provided by an implementation. Content of some types and value of some enumerations are left undefined in API spec. These are defined either in ABI spec or implementation specific (non-ABI compatible) headers .An implementation MUST use these headers AS IS, without any modifications to be compatible with ODP specification. ODP ABI compatibility specification ----------------------------------- These are the files from `include/odp/arch/@ARCH_ABI@/odp/api/abi/` directory. They specify a set of types and values that MUST be used AS IS without any modifications by an implementation if it supports and is compiled for ABI-compatibility mode. ODP default ABI headers ----------------------- These are the files from `include/odp/api/abi-default` directory. They provide default specification for ODP types and values for ABI compatibility. CPU architecture specific ABI compatibility files heavily depend on these headers. These files MUST NOT be changed by an implementation. odp_api.h header ---------------- This header found at `include/odp_api.h` is an entry point for an application. Application MUST include only odp_api.h, nothing else. This file includes all files from ODP specification. Additional ODP headers ====================== These are the headers provided by an ODP to supplement ODP specification. ODP API headers --------------- These are the files from `include/odp/api` directory. They glue together API and ABI specification headers. Although they are not part of ODP specification itself, they provide an easy way for an implementation to use ODP API/ABI header files. An implementation SHOULD use these headers AS IS unless it has strong reason not to do so. Platform-specific headers ========================= Platform ABI headers -------------------- These are the headers found at `platform/@with_platform@/include-abi/odp/api/abi` directory. They are used by the rest of ODP code if implementation is compiled with ABI compatibility disabled. They should implement at least a set of types and values documented in ODP API specification headers. They are permitted to provide any platform specific optimizations (i.e. they might provide types and/or values that map directly onto the hardware details, they might provide inline functions to speed up execution of the application, etc). These headers MAY use ODP default ABI headers if they do fit. Rest of platform-specific headers --------------------------------- Platform MAY provide additional headers at `platform/@with_platform/include`. However these headers SHOULD NOT be used directly by an application, because this will tie it to the exact implementation details. Application MUST include only header. Platform ABI headers MAY use these headers to implement platform-specific optimizations.