diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/net/fsl-tsec-phy.txt | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt b/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt index 2c6be0377f55..d2ea4605d078 100644 --- a/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt +++ b/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt @@ -86,6 +86,7 @@ General Properties: Clock Properties: + - fsl,cksel Timer reference clock source. - fsl,tclk-period Timer reference clock period in nanoseconds. - fsl,tmr-prsc Prescaler, divides the output clock. - fsl,tmr-add Frequency compensation value. @@ -97,7 +98,7 @@ Clock Properties: clock. You must choose these carefully for the clock to work right. Here is how to figure good values: - TimerOsc = system clock MHz + 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) @@ -114,6 +115,20 @@ Clock Properties: Pulse Per Second (PPS) signal, since this will be offered to the PPS subsystem to synchronize the Linux clock. + 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: + + <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. + + When this attribute is not used, eTSEC system clock will serve as + IEEE 1588 timer reference clock. + Example: ptp_clock@24E00 { @@ -121,6 +136,7 @@ Example: reg = <0x24E00 0xB0>; interrupts = <12 0x8 13 0x8>; interrupt-parent = < &ipic >; + fsl,cksel = <1>; fsl,tclk-period = <10>; fsl,tmr-prsc = <100>; fsl,tmr-add = <0x999999A4>; |