The Renesas R-Car System Controller provides power management for the CPU cores and various coprocessors, following the generic PM domain bindings in Documentation/devicetree/bindings/power/power_domain.txt.
This supports both R-Car Gen1 and Gen2. Signed-off-by: Geert Uytterhoeven <[email protected]> --- Alternatives I considered: - Using a single node per power register block, even if it contains multiple domains. - You cannot just have a property with the number of domains, as index 0 is not used on R-Car H1. Hence the need for "renesas,pm-domain-indices" and "renesas,interrupt-bits", - "#power-domain-cells = <1>" for nodes with multiple domains, which allows typos in "power-domains = <&pd_ca15_cpu n>", using an invalid value of "n", - Hence my first version had: pd_ca15_scu: ca15_scu@180 { reg = <0x180 0x20>; #address-cells = <1>; #size-cells = <0>; #power-domain-cells = <0>; renesas,interrupt-bits = <12>; pd_ca15_cpu: ca15_cpu@40 { reg = <0x40 0x20>; #power-domain-cells = <1>; renesas,pm-domain-indices = <0 1>; renesas,pm-domain-names = "ca15_cpu0", "ca15_cpu1"; renesas,interrupt-bits = <0 1>; }; }; - Using a linear description in DT - Needs parent links for subdomains, - More complicated to parse (lesson learned from R-Mobile PM Domain support). - Keeping the power register block offset and the bit number as separate "reg" cells, increasing "#address-cells" from 2 to 3, - Merging the interrupt bit (which needs only 5 bits) in the other "reg" cell, decreasing "#address-cells" from 2 to 1. .../bindings/power/renesas,sysc-rcar.txt | 82 ++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 Documentation/devicetree/bindings/power/renesas,sysc-rcar.txt diff --git a/Documentation/devicetree/bindings/power/renesas,sysc-rcar.txt b/Documentation/devicetree/bindings/power/renesas,sysc-rcar.txt new file mode 100644 index 0000000000000000..72d2fcd6beb98749 --- /dev/null +++ b/Documentation/devicetree/bindings/power/renesas,sysc-rcar.txt @@ -0,0 +1,82 @@ +DT bindings for the Renesas R-Car System Controller + +== System Controller Node == + +The R-Car System Controller provides power management for the CPU cores and +various coprocessors. + +Required properties: + - compatible: Should be "renesas,sysc-<soctype>", "renesas,sysc-rcar" as + fallback. + Examples with soctypes are: + - "renesas,sysc-r8a7779" (R-Car H1) + - "renesas,sysc-r8a7790" (R-Car H2) + - "renesas,sysc-r8a7791" (R-Car M2-W) + - "renesas,sysc-r8a7793" (R-Car M2-N) + - "renesas,sysc-r8a7794" (R-Car E2) + - reg: Address start and address range for the device. + - pm-domains: This node contains a hierarchy of PM Domain Nodes. + Dependencies (e.g. parent SCUs should not be powered off while child CPUs + are on) should be reflected using subnodes. + + +== PM Domain Nodes == + +Each of the PM domain nodes represents a PM domain, as documented by the +generic PM domain bindings in +Documentation/devicetree/bindings/power/power_domain.txt. + +Required properties: + - #power-domain-cells: Must be 0. + - reg: This property must contain 2 values: + - The first value is the number of the interrupt bit representing + the power area in the various Interrupt Registers (e.g. SYSCISR, + Interrupt Status Register), + - The second value encodes the power register block offset (which is + a multiple of 64), and the number of the bit representing the + power area in the various Power Control Registers (e.g. PWROFFSR, + Power Shutoff Status Register). This value is created by ORing + these two numbers. + The parent's node must contain the following two properties: + - #address-cells: Must be 2, + - #size-cells: Must be 0. + + +Example: + + sysc: system-controller@e6180000 { + compatible = "renesas,sysc-r8a7791", "renesas,sysc-rcar"; + reg = <0 0xe6180000 0 0x0200>; + + pm-domains { + #address-cells = <2>; + #size-cells = <0>; + + pd_ca15_scu: scu@12 { + reg = <12 0x180>; + #address-cells = <2>; + #size-cells = <0>; + #power-domain-cells = <0>; + + pd_ca15_cpu0: cpu@0 { + reg = <0 0x40>; + #power-domain-cells = <0>; + }; + + pd_ca15_cpu1: cpu@1 { + reg = <1 0x41>; + #power-domain-cells = <0>; + }; + }; + + pd_sh: sh@16 { + reg = <16 0x80>; + #power-domain-cells = <0>; + }; + + pd_sgx: sgx@20 { + reg = <20 0xc0>; + #power-domain-cells = <0>; + }; + }; + }; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
