58 lines
2.2 KiB
Plaintext
58 lines
2.2 KiB
Plaintext
* Samsung Exynos Power Domains
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Exynos processors include support for multiple power domains which are used
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to gate power to one or more peripherals on the processor.
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Required Properties:
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- compatible: should be one of the following.
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* samsung,exynos4210-pd - for exynos4210 type power domain.
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* samsung,exynos5433-pd - for exynos5433 type power domain.
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- reg: physical base address of the controller and length of memory mapped
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region.
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- #power-domain-cells: number of cells in power domain specifier;
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must be 0.
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Optional Properties:
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- label: Human readable string with domain name. Will be visible in userspace
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to let user to distinguish between multiple domains in SoC.
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- clocks: List of clock handles. The parent clocks of the input clocks to the
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devices in this power domain are set to oscclk before power gating
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and restored back after powering on a domain. This is required for
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all domains which are powered on and off and not required for unused
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domains.
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- clock-names: The following clocks can be specified:
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- oscclk: Oscillator clock.
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- clkN: Input clocks to the devices in this power domain. These clocks
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will be reparented to oscclk before switching power domain off.
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Their original parent will be brought back after turning on
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the domain. Maximum of 4 clocks (N = 0 to 3) are supported.
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- asbN: Clocks required by asynchronous bridges (ASB) present in
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the power domain. These clock should be enabled during power
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domain on/off operations.
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- power-domains: phandle pointing to the parent power domain, for more details
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see Documentation/devicetree/bindings/power/power_domain.txt
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Node of a device using power domains must have a power-domains property
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defined with a phandle to respective power domain.
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Example:
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lcd0: power-domain-lcd0 {
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compatible = "samsung,exynos4210-pd";
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reg = <0x10023C00 0x10>;
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#power-domain-cells = <0>;
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label = "LCD0";
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};
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mfc_pd: power-domain@10044060 {
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compatible = "samsung,exynos4210-pd";
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reg = <0x10044060 0x20>;
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clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_USER_ACLK333>;
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clock-names = "oscclk", "clk0";
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#power-domain-cells = <0>;
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label = "MFC";
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};
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See Documentation/devicetree/bindings/power/power_domain.txt for description
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of consumer-side bindings.
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