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diff --git a/Documentation/interconnect/interconnect.rst b/Documentation/interconnect/interconnect.rst deleted file mode 100644 index b8107dcc4cd3..000000000000 --- a/Documentation/interconnect/interconnect.rst +++ /dev/null @@ -1,94 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -===================================== -GENERIC SYSTEM INTERCONNECT SUBSYSTEM -===================================== - -Introduction ------------- - -This framework is designed to provide a standard kernel interface to control -the settings of the interconnects on an SoC. These settings can be throughput, -latency and priority between multiple interconnected devices or functional -blocks. This can be controlled dynamically in order to save power or provide -maximum performance. - -The interconnect bus is hardware with configurable parameters, which can be -set on a data path according to the requests received from various drivers. -An example of interconnect buses are the interconnects between various -components or functional blocks in chipsets. There can be multiple interconnects -on an SoC that can be multi-tiered. - -Below is a simplified diagram of a real-world SoC interconnect bus topology. - -:: - - +----------------+ +----------------+ - | HW Accelerator |--->| M NoC |<---------------+ - +----------------+ +----------------+ | - | | +------------+ - +-----+ +-------------+ V +------+ | | - | DDR | | +--------+ | PCIe | | | - +-----+ | | Slaves | +------+ | | - ^ ^ | +--------+ | | C NoC | - | | V V | | - +------------------+ +------------------------+ | | +-----+ - | |-->| |-->| |-->| CPU | - | |-->| |<--| | +-----+ - | Mem NoC | | S NoC | +------------+ - | |<--| |---------+ | - | |<--| |<------+ | | +--------+ - +------------------+ +------------------------+ | | +-->| Slaves | - ^ ^ ^ ^ ^ | | +--------+ - | | | | | | V - +------+ | +-----+ +-----+ +---------+ +----------------+ +--------+ - | CPUs | | | GPU | | DSP | | Masters |-->| P NoC |-->| Slaves | - +------+ | +-----+ +-----+ +---------+ +----------------+ +--------+ - | - +-------+ - | Modem | - +-------+ - -Terminology ------------ - -Interconnect provider is the software definition of the interconnect hardware. -The interconnect providers on the above diagram are M NoC, S NoC, C NoC, P NoC -and Mem NoC. - -Interconnect node is the software definition of the interconnect hardware -port. Each interconnect provider consists of multiple interconnect nodes, -which are connected to other SoC components including other interconnect -providers. The point on the diagram where the CPUs connect to the memory is -called an interconnect node, which belongs to the Mem NoC interconnect provider. - -Interconnect endpoints are the first or the last element of the path. Every -endpoint is a node, but not every node is an endpoint. - -Interconnect path is everything between two endpoints including all the nodes -that have to be traversed to reach from a source to destination node. It may -include multiple master-slave pairs across several interconnect providers. - -Interconnect consumers are the entities which make use of the data paths exposed -by the providers. The consumers send requests to providers requesting various -throughput, latency and priority. Usually the consumers are device drivers, that -send request based on their needs. An example for a consumer is a video decoder -that supports various formats and image sizes. - -Interconnect providers ----------------------- - -Interconnect provider is an entity that implements methods to initialize and -configure interconnect bus hardware. The interconnect provider drivers should -be registered with the interconnect provider core. - -.. kernel-doc:: include/linux/interconnect-provider.h - -Interconnect consumers ----------------------- - -Interconnect consumers are the clients which use the interconnect APIs to -get paths between endpoints and set their bandwidth/latency/QoS requirements -for these interconnect paths. - -.. kernel-doc:: include/linux/interconnect.h |