These OPPs are used in ST's CPUFreq implementation. Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx> --- Changelog: - None, new patch Documentation/devicetree/bindings/power/opp-st.txt | 76 ++++++++++++++++++++++ 1 file changed, 76 insertions(+) create mode 100644 Documentation/devicetree/bindings/power/opp-st.txt diff --git a/Documentation/devicetree/bindings/power/opp-st.txt b/Documentation/devicetree/bindings/power/opp-st.txt new file mode 100644 index 0000000..6eb2a91 --- /dev/null +++ b/Documentation/devicetree/bindings/power/opp-st.txt @@ -0,0 +1,76 @@ +STMicroelectronics OPP (Operating Performance Points) Bindings +-------------------------------------------------------------- + +Frequency Scaling only +---------------------- + +Located in CPU's node: + +- operating-points : [See: ./opp.txt] + +Example [safe] +-------------- + +cpus { + cpu@0 { + /* kHz uV */ + operating-points = <1500000 0 + 1200000 0 + 800000 0 + 500000 0>; + }; +}; + +Dynamic Voltage and Frequency Scaling (DVFS) +-------------------------------------------- + +Located in 'cpu0-opp-list' node [to be provided ONLY by the bootloader]: + +- compatible : Should be "operating-points-v2-sti" +- opp{1..N} : Each 'oppX' subnode will contain the following properties: + - opp-hz : CPU frequency [Hz] for this OPP [See: ./opp.txt] + - st,avs : List of available voltages [uV] indexed by process code + - st,cuts : Cut version this OPP is suitable for [0xFF means ALL] + - st,substrate : Substrate version this OPP is suitable for [0xFF means ALL] +- st,syscfg : Phandle to Major number register + First cell: offset to major number +- st,syscfg-eng : Phandle to Minor number and Pcode registers + First cell: offset to process code + Second cell: offset to minor number + +WARNING: The opp{1..N} nodes will be provided by the bootloader. Do not attempt to + artificially synthesise the opp{1..N} nodes or any of their descendants. + They are very platform specific and may damage the hardware if created + incorrectly. + +Example [unsafe] +---------------- + +cpus { + cpu@0 { + operating-points-v2 = <&cpu0_opp_list>; + }; +}; + +/* ############################################################ */ +/* # WARNING: Do not attempt to copy/replicate this node, # */ +/* # it is only to be supplied by the bootloader !!! # */ +/* ############################################################ */ +cpu0-opp-list { + compatible = "operating-points-v2-sti"; + st,syscfg = <&syscfg [major_offset]>; + st,syscfg-eng = <&syscfg_eng [pcode_offset] [minor_offset]>; + + opp0 { + opp-hz = <1200000000>; + st,avs = <1110 1150 1100 1080 1040 1020 980 930>; + st,substrate = <0xff>; + st,cuts = <0xff>; + }; + opp1 { + opp-hz = <1500000000>; + st,avs = <1200 1200 1200 1200 1170 1140 1100 1070>; + st,substrate = <0xff>; + st,cuts = <0x2>; + }; +}; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html