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
---
Documentation/devicetree/bindings/net/fsl-tsec-phy.txt | 18 +-
drivers/net/ethernet/freescale/gianfar_ptp.c | 4 +++-
2 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt
b/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt
index 2c6be03..d2ea460 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,ckselTimer 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 = <0x99A4>;
diff --git a/drivers/net/ethernet/freescale/gianfar_ptp.c
b/drivers/net/ethernet/freescale/gianfar_ptp.c
index 098f133..e006a09 100644
--- a/drivers/net/ethernet/freescale/gianfar_ptp.c
+++ b/drivers/net/ethernet/freescale/gianfar_ptp.c
@@ -452,7 +452,9 @@ static int gianfar_ptp_probe(struct platform_device *dev)
err = -ENODEV;
etsects->caps = ptp_gianfar_caps;
- etsects->cksel = DEFAULT_CKSEL;
+
+ if (get_of_u32(node, "fsl,cksel", &etsects->cksel))
+ etsects->cksel = DEFAULT_CKSEL;
if (get_of_u32(node, "fsl,tclk-period", &etsects->tclk_period) ||
get_of_u32(node, "fsl,tmr-prsc", &etsects->tmr_prsc) ||
--
1.8.1.2
___
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
