Cc: devicetree@xxxxxxxxxxxxxxx Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx> --- Only submitting the binding document as requested by Viresh. v2 => v3: - Using OPP v2 - Moved OPPs out of the CPU node into their own one - Using generic 'opp-hz' property .../devicetree/bindings/cpufreq/cpufreq-st.txt | 77 ++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 Documentation/devicetree/bindings/cpufreq/cpufreq-st.txt diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-st.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-st.txt new file mode 100644 index 0000000..a478eec --- /dev/null +++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-st.txt @@ -0,0 +1,77 @@ +Binding for ST's CPUFreq driver +=============================== + +Required properties [for working voltage scaling]: +------------------------------------------------- + +Located in CPU's node: + +- 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 + +Located in 'cpu0-opp-list' node [to be provided ONLY by the bootloader]: + + - opp{1..N} : Each 'oppX' subnode will contain the following properties: + - opp-hz : CPU frequency [Hz] for this OPP + - 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] + +WARNING: The cpu0-opp-list will be provided by the bootloader. Do not attempt to + artificially synthesise the cpu0-opp-list node or any of its descendants. + They are very platform specific and may damage the hardware if created + incorrectly. + +Required properties [if voltage scaling properties are missing]: +------------------------------------------------------------------- + +Located in CPU's node: + +- operating-points : [See: ../power/opp.txt] + +Example [safe]: +-------------- + +cpus { + cpu@0 { + /* kHz uV */ + operating-points = <1500000 0 + 1200000 0 + 800000 0 + 500000 0>; + }; +}; + +Example [unsafe]: +---------------- + +cpus { + cpu@0 { + st,syscfg = <&syscfg [major_offset]>; + st,syscfg-eng = <&syscfg_eng [pcode_offset] [minor_offset]>; + 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"; + 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