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author | Aida Mynzhasova <aida.mynzhasova@skitlab.ru> | 2013-09-25 11:24:23 +0400 |
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committer | David S. Miller <davem@davemloft.net> | 2013-09-30 22:49:47 +0400 |
commit | 894116bd0e9b7749a0c4b6c62dec13c2a0ccef68 (patch) | |
tree | a3e9709ce7d977964417ed27e531763fa7526e5a /Documentation | |
parent | 559835ea7292e2f09304d81eda16f4209433245e (diff) | |
download | linux-894116bd0e9b7749a0c4b6c62dec13c2a0ccef68.tar.xz |
powerpc/83xx: gianfar_ptp: select 1588 clock source through dts file
Currently IEEE 1588 timer reference clock source is determined through
hard-coded value in gianfar_ptp driver. This patch allows to select ptp
clock source by means of device tree file node.
For instance:
fsl,cksel = <0>;
for using external (TSEC_TMR_CLK input) high precision timer
reference clock.
Other acceptable values:
<1> : eTSEC system clock
<2> : eTSEC1 transmit clock
<3> : RTC clock input
When this attribute isn't used, eTSEC system clock will serve as
IEEE 1588 timer reference clock.
Signed-off-by: Aida Mynzhasova <aida.mynzhasova@skitlab.ru>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/net/fsl-tsec-phy.txt | 16 |
1 files changed, 15 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..eb06059f3cf3 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 +115,18 @@ Clock Properties: Pulse Per Second (PPS) signal, since this will be offered to the PPS subsystem to synchronize the Linux clock. + "fsl,cksel" property allows to select different reference clock + sources: + + <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 +134,7 @@ 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>; |