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diff --git a/Documentation/acpi/dsd/graph.txt b/Documentation/acpi/dsd/graph.txt deleted file mode 100644 index ac09e3138b79..000000000000 --- a/Documentation/acpi/dsd/graph.txt +++ /dev/null @@ -1,162 +0,0 @@ -Graphs - - -_DSD ----- - -_DSD (Device Specific Data) [7] is a predefined ACPI device -configuration object that can be used to convey information on -hardware features which are not specifically covered by the ACPI -specification [1][6]. There are two _DSD extensions that are relevant -for graphs: property [4] and hierarchical data extensions [5]. The -property extension provides generic key-value pairs whereas the -hierarchical data extension supports nodes with references to other -nodes, forming a tree. The nodes in the tree may contain properties as -defined by the property extension. The two extensions together provide -a tree-like structure with zero or more properties (key-value pairs) -in each node of the tree. - -The data structure may be accessed at runtime by using the device_* -and fwnode_* functions defined in include/linux/fwnode.h . - -Fwnode represents a generic firmware node object. It is independent on -the firmware type. In ACPI, fwnodes are _DSD hierarchical data -extensions objects. A device's _DSD object is represented by an -fwnode. - -The data structure may be referenced to elsewhere in the ACPI tables -by using a hard reference to the device itself and an index to the -hierarchical data extension array on each depth. - - -Ports and endpoints -------------------- - -The port and endpoint concepts are very similar to those in Devicetree -[3]. A port represents an interface in a device, and an endpoint -represents a connection to that interface. - -All port nodes are located under the device's "_DSD" node in the -hierarchical data extension tree. The property extension related to -each port node must contain the key "port" and an integer value which -is the number of the port. The object it refers to should be called "PRTX", -where "X" is the number of the port. - -Further on, endpoints are located under the individual port nodes. The -first hierarchical data extension package list entry of the endpoint -nodes must begin with "endpoint" and must be followed by the number -of the endpoint. The object it refers to should be called "EPXY", where -"X" is the number of the port and "Y" is the number of the endpoint. - -Each port node contains a property extension key "port", the value of -which is the number of the port node. The each endpoint is similarly numbered -with a property extension key "endpoint". Port numbers must be unique within a -device and endpoint numbers must be unique within a port. - -The endpoint reference uses property extension with "remote-endpoint" property -name followed by a reference in the same package. Such references consist of the -the remote device reference, number of the port in the device and finally the -number of the endpoint in that port. Individual references thus appear as: - - Package() { device, port_number, endpoint_number } - -The references to endpoints must be always done both ways, to the -remote endpoint and back from the referred remote endpoint node. - -A simple example of this is show below: - - Scope (\_SB.PCI0.I2C2) - { - Device (CAM0) - { - Name (_DSD, Package () { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "compatible", Package () { "nokia,smia" } }, - }, - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "port0", "PRT0" }, - } - }) - Name (PRT0, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "port", 0 }, - }, - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "endpoint0", "EP00" }, - } - }) - Name (EP00, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "endpoint", 0 }, - Package () { "remote-endpoint", Package() { \_SB.PCI0.ISP, 4, 0 } }, - } - }) - } - } - - Scope (\_SB.PCI0) - { - Device (ISP) - { - Name (_DSD, Package () { - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "port4", "PRT4" }, - } - }) - - Name (PRT4, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "port", 4 }, /* CSI-2 port number */ - }, - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "endpoint0", "EP40" }, - } - }) - - Name (EP40, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "endpoint", 0 }, - Package () { "remote-endpoint", Package () { \_SB.PCI0.I2C2.CAM0, 0, 0 } }, - } - }) - } - } - -Here, the port 0 of the "CAM0" device is connected to the port 4 of -the "ISP" device and vice versa. - - -References ----------- - -[1] _DSD (Device Specific Data) Implementation Guide. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel-1_1.htm>, - referenced 2016-10-03. - -[2] Devicetree. <URL:http://www.devicetree.org>, referenced 2016-10-03. - -[3] Documentation/devicetree/bindings/graph.txt - -[4] Device Properties UUID For _DSD. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>, - referenced 2016-10-04. - -[5] Hierarchical Data Extension UUID For _DSD. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.pdf>, - referenced 2016-10-04. - -[6] Advanced Configuration and Power Interface Specification. - <URL:http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf>, - referenced 2016-10-04. - -[7] _DSD Device Properties Usage Rules. - Documentation/acpi/DSD-properties-rules.txt |