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diff --git a/Documentation/devicetree/bindings/clock/at91-clock.txt b/Documentation/devicetree/bindings/clock/at91-clock.txt new file mode 100644 index 0000000..cd5e239 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/at91-clock.txt @@ -0,0 +1,339 @@ +Device Tree Clock bindings for arch-at91 + +This binding uses the common clock binding[1]. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- compatible : shall be one of the following: + "atmel,at91rm9200-pmc" or + "atmel,at91sam9g45-pmc" or + "atmel,at91sam9n12-pmc" or + "atmel,at91sam9x5-pmc" or + "atmel,sama5d3-pmc": + at91 PMC (Power Management Controller) + All at91 specific clocks (clocks defined below) must be child + node of the PMC node. + + "atmel,at91rm9200-clk-main": + at91 main oscillator + + "atmel,at91rm9200-clk-master" or + "atmel,at91sam9x5-clk-master": + at91 master clock + + "atmel,at91sam9x5-clk-peripheral" or + "atmel,at91rm9200-clk-peripheral": + at91 peripheral clocks + + "atmel,at91rm9200-clk-pll" or + "atmel,at91sam9g45-clk-pll" or + "atmel,at91sam9g20-clk-pllb" or + "atmel,sama5d3-clk-pll": + at91 pll clocks + + "atmel,at91sam9x5-clk-plldiv": + at91 plla divisor + + "atmel,at91rm9200-clk-programmable" or + "atmel,at91sam9g45-clk-programmable" or + "atmel,at91sam9x5-clk-programmable": + at91 programmable clocks + + "atmel,at91sam9x5-clk-smd": + at91 SMD (Soft Modem) clock + + "atmel,at91rm9200-clk-system": + at91 system clocks + + "atmel,at91rm9200-clk-usb" or + "atmel,at91sam9x5-clk-usb" or + "atmel,at91sam9n12-clk-usb": + at91 usb clock + + "atmel,at91sam9x5-clk-utmi": + at91 utmi clock + +Required properties for PMC node: +- reg : defines the IO memory reserved for the PMC. +- #size-cells : shall be 0 (reg is used to encode clk id). +- #address-cells : shall be 1 (reg is used to encode clk id). +- interrupts : shall be set to PMC interrupt line. +- interrupt-controller : tell that the PMC is an interrupt controller. +- #interrupt-cells : must be set to 1. The first cell encodes the interrupt id, + and reflect the bit position in the PMC_ER/DR/SR registers. + You can use the dt macros defined in dt-bindings/clk/at91.h. + 0 (AT91_PMC_MOSCS) -> main oscillator ready + 1 (AT91_PMC_LOCKA) -> PLL A ready + 2 (AT91_PMC_LOCKB) -> PLL B ready + 3 (AT91_PMC_MCKRDY) -> master clock ready + 6 (AT91_PMC_LOCKU) -> UTMI PLL clock ready + 8 .. 15 (AT91_PMC_PCKRDY(id)) -> programmable clock ready + 16 (AT91_PMC_MOSCSELS) -> main oscillator selected + 17 (AT91_PMC_MOSCRCS) -> RC main oscillator stabilized + 18 (AT91_PMC_CFDEV) -> clock failure detected + +For example: + pmc: pmc@fffffc00 { + compatible = "atmel,sama5d3-pmc"; + interrupts = <1 4 7>; + interrupt-controller; + #interrupt-cells = <2>; + #size-cells = <0>; + #address-cells = <1>; + + /* put at91 clocks here */ + }; + +Required properties for main clock: +- interrupt-parent : must reference the PMC node. +- interrupts : shall be set to "<0>". +- #clock-cells : from common clock binding; shall be set to 0. +- clocks (optional if clock-frequency is provided) : shall be the slow clock + phandle. This clock is used to calculate the main clock rate if + "clock-frequency" is not provided. +- clock-frequency : the main oscillator frequency.Prefer the use of + "clock-frequency" over automatic clock rate calculation. + +For example: + main: mainck { + compatible = "atmel,at91rm9200-clk-main"; + interrupt-parent = <&pmc>; + interrupts = <0>; + #clock-cells = <0>; + clocks = <&ck32k>; + clock-frequency = <18432000>; + }; + +Required properties for master clock: +- interrupt-parent : must reference the PMC node. +- interrupts : shall be set to "<3>". +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : shall be the master clock sources (see atmel datasheet) phandles. + e.g. "<&ck32k>, <&main>, <&plla>, <&pllb>". +- atmel,clk-output-range : minimum and maximum clock frequency (two u32 + fields). + e.g. output = <0 133000000>; <=> 0 to 133MHz. +- atmel,clk-divisors : master clock divisors table (four u32 fields). + 0 <=> reserved value. + e.g. divisors = <1 2 4 6>; +- atmel,master-clk-have-div3-pres : some SoC use the reserved value 7 in the + PRES field as CLOCK_DIV3 (e.g sam9x5). + +For example: + mck: mck { + compatible = "atmel,at91rm9200-clk-master"; + interrupt-parent = <&pmc>; + interrupts = <3>; + #clock-cells = <0>; + atmel,clk-output-range = <0 133000000>; + atmel,clk-divisors = <1 2 4 0>; + }; + +Required properties for peripheral clocks: +- #size-cells : shall be 0 (reg is used to encode clk id). +- #address-cells : shall be 1 (reg is used to encode clk id). +- clocks : shall be the master clock phandle. + e.g. clocks = <&mck>; +- name: device tree node describing a specific system clock. + * #clock-cells : from common clock binding; shall be set to 0. + * reg: peripheral id. See Atmel's datasheets to get a full + list of peripheral ids. + * atmel,clk-output-range : minimum and maximum clock frequency + (two u32 fields). Only valid on at91sam9x5-clk-peripheral + compatible IPs. + +For example: + periph: periphck { + compatible = "atmel,at91sam9x5-clk-peripheral"; + #size-cells = <0>; + #address-cells = <1>; + clocks = <&mck>; + + ssc0_clk { + #clock-cells = <0>; + reg = <2>; + atmel,clk-output-range = <0 133000000>; + }; + + usart0_clk { + #clock-cells = <0>; + reg = <3>; + atmel,clk-output-range = <0 66000000>; + }; + }; + + +Required properties for pll clocks: +- interrupt-parent : must reference the PMC node. +- interrupts : shall be set to "<1>". +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : shall be the main clock phandle. +- reg : pll id. + 0 -> PLL A + 1 -> PLL B +- atmel,clk-input-range : minimum and maximum source clock frequency (two u32 + fields). + e.g. input = <1 32000000>; <=> 1 to 32MHz. +- #atmel,pll-clk-output-range-cells : number of cells reserved for pll output + range description. Sould be set to 2, 3 + or 4. + * 1st and 2nd cells represent the frequency range (min-max). + * 3rd cell is optional and represents the OUT field value for the given + range. + * 4th cell is optional and represents the ICPLL field (PLLICPR + register) +- atmel,pll-clk-output-ranges : pll output frequency ranges + optional parameter + depending on #atmel,pll-output-range-cells + property value. + +For example: + plla: pllack { + compatible = "atmel,at91sam9g45-clk-pll"; + interrupt-parent = <&pmc>; + interrupts = <1>; + #clock-cells = <0>; + clocks = <&main>; + reg = <0>; + atmel,clk-input-range = <2000000 32000000>; + #atmel,pll-clk-output-range-cells = <4>; + atmel,pll-clk-output-ranges = <74500000 800000000 0 0 + 69500000 750000000 1 0 + 64500000 700000000 2 0 + 59500000 650000000 3 0 + 54500000 600000000 0 1 + 49500000 550000000 1 1 + 44500000 500000000 2 1 + 40000000 450000000 3 1>; + }; + +Required properties for plldiv clocks (plldiv = pll / 2): +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : shall be the plla clock phandle. + +The pll divisor is equal to 2 and cannot be changed. + +For example: + plladiv: plladivck { + compatible = "atmel,at91sam9x5-clk-plldiv"; + #clock-cells = <0>; + clocks = <&plla>; + }; + +Required properties for programmable clocks: +- interrupt-parent : must reference the PMC node. +- #size-cells : shall be 0 (reg is used to encode clk id). +- #address-cells : shall be 1 (reg is used to encode clk id). +- clocks : shall be the programmable clock source phandles. + e.g. clocks = <&clk32k>, <&main>, <&plla>, <&pllb>; +- name: device tree node describing a specific prog clock. + * #clock-cells : from common clock binding; shall be set to 0. + * reg : programmable clock id (register offset from PCKx + register). + * interrupts : shall be set to "<(8 + id)>". + +For example: + prog: progck { + compatible = "atmel,at91sam9g45-clk-programmable"; + #size-cells = <0>; + #address-cells = <1>; + interrupt-parent = <&pmc>; + clocks = <&clk32k>, <&main>, <&plladiv>, <&utmi>, <&mck>; + + prog0 { + #clock-cells = <0>; + reg = <0>; + interrupts = <8>; + }; + + prog1 { + #clock-cells = <0>; + reg = <1>; + interrupts = <9>; + }; + }; + + +Required properties for smd clock: +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : shall be the smd clock source phandles. + e.g. clocks = <&plladiv>, <&utmi>; + +For example: + smd: smdck { + compatible = "atmel,at91sam9x5-clk-smd"; + #clock-cells = <0>; + clocks = <&plladiv>, <&utmi>; + }; + +Required properties for system clocks: +- #size-cells : shall be 0 (reg is used to encode clk id). +- #address-cells : shall be 1 (reg is used to encode clk id). +- name: device tree node describing a specific system clock. + * #clock-cells : from common clock binding; shall be set to 0. + * reg: system clock id (bit position in SCER/SCDR/SCSR registers). + See Atmel's datasheet to get a full list of system clock ids. + +For example: + system: systemck { + compatible = "atmel,at91rm9200-clk-system"; + #address-cells = <1>; + #size-cells = <0>; + + ddrck { + #clock-cells = <0>; + reg = <2>; + clocks = <&mck>; + }; + + uhpck { + #clock-cells = <0>; + reg = <6>; + clocks = <&usb>; + }; + + udpck { + #clock-cells = <0>; + reg = <7>; + clocks = <&usb>; + }; + }; + + +Required properties for usb clock: +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : shall be the smd clock source phandles. + e.g. clocks = <&pllb>; +- atmel,clk-divisors (only available for "atmel,at91rm9200-clk-usb"): + usb clock divisor table. + e.g. divisors = <1 2 4 0>; + +For example: + usb: usbck { + compatible = "atmel,at91sam9x5-clk-usb"; + #clock-cells = <0>; + clocks = <&plladiv>, <&utmi>; + }; + + usb: usbck { + compatible = "atmel,at91rm9200-clk-usb"; + #clock-cells = <0>; + clocks = <&pllb>; + atmel,clk-divisors = <1 2 4 0>; + }; + + +Required properties for utmi clock: +- interrupt-parent : must reference the PMC node. +- interrupts : shall be set to "<AT91_PMC_LOCKU IRQ_TYPE_LEVEL_HIGH>". +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : shall be the main clock source phandle. + +For example: + utmi: utmick { + compatible = "atmel,at91sam9x5-clk-utmi"; + interrupt-parent = <&pmc>; + interrupts = <AT91_PMC_LOCKU IRQ_TYPE_LEVEL_HIGH>; + #clock-cells = <0>; + clocks = <&main>; + }; |