66 lines
2.1 KiB
Plaintext
66 lines
2.1 KiB
Plaintext
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Texas Instruments TI-SCI Generic Power Domain
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---------------------------------------------
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Some TI SoCs contain a system controller (like the PMMC, etc...) that is
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responsible for controlling the state of the IPs that are present.
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Communication between the host processor running an OS and the system
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controller happens through a protocol known as TI-SCI [1].
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[1] Documentation/devicetree/bindings/arm/keystone/ti,sci.txt
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PM Domain Node
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==============
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The PM domain node represents the global PM domain managed by the PMMC, which
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in this case is the implementation as documented by the generic PM domain
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bindings in Documentation/devicetree/bindings/power/power_domain.txt. Because
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this relies on the TI SCI protocol to communicate with the PMMC it must be a
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child of the pmmc node.
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Required Properties:
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--------------------
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- compatible: should be "ti,sci-pm-domain"
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- #power-domain-cells: Can be one of the following:
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1: Containing the device id of each node
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2: First entry should be device id
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Second entry should be one of the floowing:
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TI_SCI_PD_EXCLUSIVE: To allow device to be
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exclusively controlled by
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the requesting hosts.
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TI_SCI_PD_SHARED: To allow device to be shared
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by multiple hosts.
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Example (K2G):
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-------------
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pmmc: pmmc {
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compatible = "ti,k2g-sci";
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...
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k2g_pds: power-controller {
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compatible = "ti,sci-pm-domain";
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#power-domain-cells = <1>;
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};
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};
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PM Domain Consumers
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===================
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Hardware blocks belonging to a PM domain should contain a "power-domains"
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property that is a phandle pointing to the corresponding PM domain node
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along with an index representing the device id to be passed to the PMMC
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for device control.
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Required Properties:
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--------------------
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- power-domains: phandle pointing to the corresponding PM domain node
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and an ID representing the device.
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See http://processors.wiki.ti.com/index.php/TISCI#66AK2G02_Data for the list
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of valid identifiers for k2g.
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Example (K2G):
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--------------------
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uart0: serial@2530c00 {
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compatible = "ns16550a";
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...
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power-domains = <&k2g_pds 0x002c>;
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};
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