On 14/06/2024 22:33, Frank Li wrote: > diff --git a/Documentation/devicetree/bindings/ptp/ptp-qoriq.yaml b/Documentation/devicetree/bindings/ptp/ptp-qoriq.yaml > new file mode 100644 > index 0000000000000..585e8bffd90c9 > --- /dev/null > +++ b/Documentation/devicetree/bindings/ptp/ptp-qoriq.yaml Filename based on compatible. Can be fsl,ptp.yaml > @@ -0,0 +1,148 @@ > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/ptp/ptp-qoriq.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Freescale QorIQ 1588 timer based PTP clock > + > +maintainers: > + - Frank Li <Frank.Li@xxxxxxx> > + > +properties: > + compatible: > + enum: > + - fsl,etsec-ptp > + - fsl,fman-ptp-timer > + - fsl,dpaa2-ptp > + - fsl,enetc-ptp > + description: | > + Should be "fsl,etsec-ptp" for eTSEC > + Should be "fsl,fman-ptp-timer" for DPAA FMan > + Should be "fsl,dpaa2-ptp" for DPAA2 > + Should be "fsl,enetc-ptp" for ENETC You can write it simpler, e.g. - fsl,etsec-ptp # eTSEC and then you see that this does not bring any new information - your comment duplicates the compatible. Just drop. > + > + reg: > + maxItems: 1 > + > + interrupts: > + minItems: 2 > + maxItems: 4 Items should be described. > + > + clocks: > + maxItems: 1 > + > + fsl,cksel: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: | > + Timer reference clock source. > + > + Reference clock source is determined by the value, which is holded > + in CKSEL bits in TMR_CTRL register. "fsl,cksel" property keeps the > + value, which will be directly written in those bits, that is why, > + according to reference manual, the next clock sources can be used: > + > + For eTSEC, > + <0> - external high precision timer reference clock (TSEC_TMR_CLK > + input is used for this purpose); > + <1> - eTSEC system clock; > + <2> - eTSEC1 transmit clock; > + <3> - RTC clock input. > + > + For DPAA FMan, > + <0> - external high precision timer reference clock (TMR_1588_CLK) > + <1> - MAC system clock (1/2 FMan clock) > + <2> - reserved > + <3> - RTC clock oscillator > + > + fsl,tclk-period: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: Timer reference clock period in nanoseconds. > + > + fsl,tmr-prsc: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: Prescaler, divides the output clock. > + > + fsl,tmr-add: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: Frequency compensation value. > + > + fsl,tmr-fiper1: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: Fixed interval period pulse generator. > + > + fsl,tmr-fiper2: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: Fixed interval period pulse generator. > + > + fsl,tmr-fiper3: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: > + Fixed interval period pulse generator. > + Supported only on DPAA2 and ENETC hardware. > + > + fsl,max-adj: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: | > + Maximum frequency adjustment in parts per billion. > + > + These properties set the operational parameters for the PTP > + clock. You must choose these carefully for the clock to work right. > + Here is how to figure good values: > + > + TimerOsc = selected reference clock MHz > + tclk_period = desired clock period nanoseconds > + NominalFreq = 1000 / tclk_period MHz > + FreqDivRatio = TimerOsc / NominalFreq (must be greater that 1.0) > + tmr_add = ceil(2^32 / FreqDivRatio) > + OutputClock = NominalFreq / tmr_prsc MHz > + PulseWidth = 1 / OutputClock microseconds > + FiperFreq1 = desired frequency in Hz > + FiperDiv1 = 1000000 * OutputClock / FiperFreq1 > + tmr_fiper1 = tmr_prsc * tclk_period * FiperDiv1 - tclk_period > + max_adj = 1000000000 * (FreqDivRatio - 1.0) - 1 > + > + The calculation for tmr_fiper2 is the same as for tmr_fiper1. The > + driver expects that tmr_fiper1 will be correctly set to produce a 1 > + Pulse Per Second (PPS) signal, since this will be offered to the PPS > + subsystem to synchronize the Linux clock. > + > + When this attribute is not used, the IEEE 1588 timer reference clock > + will use the eTSEC system clock (for Gianfar) or the MAC system > + clock (for DPAA). > + > + fsl,extts-fifo: > + $ref: /schemas/types.yaml#/definitions/flag > + description: > + The presence of this property indicates hardware > + support for the external trigger stamp FIFO > + > + little-endian: > + $ref: /schemas/types.yaml#/definitions/flag > + description: > + The presence of this property indicates the 1588 timer > + support for the external trigger stamp FIFO. > + IP block is little-endian mode. The default endian mode > + is big-endian. > + > +required: > + - compatible > + - reg > + > +additionalProperties: false > + > +examples: > + - | > + ptp_clock@24e00 { phc@ > + compatible = "fsl,etsec-ptp"; > + reg = <0x24E00 0xB0>; Lowercase hex, in other places as well. > + interrupts = <12 0x8>, <13 0x8>; Use proper defines for interrupt flags. > + interrupt-parent = <&ipic>; > + fsl,cksel = <1>; Best regards, Krzysztof
