diff options
Diffstat (limited to 'Documentation/devicetree/bindings/net')
| -rwxr-xr-x | Documentation/devicetree/bindings/net/can/fsl-flexcan.txt | 61 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/net/fsl-tsec-phy.txt | 54 |
2 files changed, 115 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt new file mode 100755 index 00000000000..1a729f08986 --- /dev/null +++ b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt @@ -0,0 +1,61 @@ +CAN Device Tree Bindings +------------------------ +2011 Freescale Semiconductor, Inc. + +fsl,flexcan-v1.0 nodes +----------------------- +In addition to the required compatible-, reg- and interrupt-properties, you can +also specify which clock source shall be used for the controller. + +CPI Clock- Can Protocol Interface Clock + This CLK_SRC bit of CTRL(control register) selects the clock source to + the CAN Protocol Interface(CPI) to be either the peripheral clock + (driven by the PLL) or the crystal oscillator clock. The selected clock + is the one fed to the prescaler to generate the Serial Clock (Sclock). + The PRESDIV field of CTRL(control register) controls a prescaler that + generates the Serial Clock (Sclock), whose period defines the + time quantum used to compose the CAN waveform. + +Can Engine Clock Source + There are two sources for CAN clock + - Platform Clock It represents the bus clock + - Oscillator Clock + + Peripheral Clock (PLL) + -------------- + | + --------- ------------- + | |CPI Clock | Prescaler | Sclock + | |---------------->| (1.. 256) |------------> + --------- ------------- + | | + -------------- ---------------------CLK_SRC + Oscillator Clock + +- fsl,flexcan-clock-source : CAN Engine Clock Source.This property selects + the peripheral clock. PLL clock is fed to the + prescaler to generate the Serial Clock (Sclock). + Valid values are "oscillator" and "platform" + "oscillator": CAN engine clock source is oscillator clock. + "platform" The CAN engine clock source is the bus clock + (platform clock). + +- fsl,flexcan-clock-divider : for the reference and system clock, an additional + clock divider can be specified. +- clock-frequency: frequency required to calculate the bitrate for FlexCAN. + +Note: + - v1.0 of flexcan-v1.0 represent the IP block version for P1010 SOC. + - P1010 does not have oscillator as the Clock Source.So the default + Clock Source is platform clock. +Examples: + + can0@1c000 { + compatible = "fsl,flexcan-v1.0"; + reg = <0x1c000 0x1000>; + interrupts = <48 0x2>; + interrupt-parent = <&mpic>; + fsl,flexcan-clock-source = "platform"; + fsl,flexcan-clock-divider = <2>; + clock-frequency = <fixed by u-boot>; + }; diff --git a/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt b/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt index edb7ae19e86..2c6be0377f5 100644 --- a/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt +++ b/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt @@ -74,3 +74,57 @@ Example: interrupt-parent = <&mpic>; phy-handle = <&phy0> }; + +* Gianfar PTP clock nodes + +General Properties: + + - compatible Should be "fsl,etsec-ptp" + - reg Offset and length of the register set for the device + - interrupts There should be at least two interrupts. Some devices + have as many as four PTP related interrupts. + +Clock Properties: + + - fsl,tclk-period Timer reference clock period in nanoseconds. + - fsl,tmr-prsc Prescaler, divides the output clock. + - fsl,tmr-add Frequency compensation value. + - fsl,tmr-fiper1 Fixed interval period pulse generator. + - fsl,tmr-fiper2 Fixed interval period pulse generator. + - fsl,max-adj 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 = system 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. + +Example: + + ptp_clock@24E00 { + compatible = "fsl,etsec-ptp"; + reg = <0x24E00 0xB0>; + interrupts = <12 0x8 13 0x8>; + interrupt-parent = < &ipic >; + fsl,tclk-period = <10>; + fsl,tmr-prsc = <100>; + fsl,tmr-add = <0x999999A4>; + fsl,tmr-fiper1 = <0x3B9AC9F6>; + fsl,tmr-fiper2 = <0x00018696>; + fsl,max-adj = <659999998>; + }; |