lx2160ardb PTP pps,frames loss(reset ptp server) ptp_pps phase jump

[wutianyi]

Hi :
    When I was running PTP4l in lx2160ardb_rev2, I found that when I restarted the ptp server, the phase of 1PPS output by ptp4l would jump sharply. I expect him to stay in phase and then change slowly.

Thanks
Tianyi

[yipingwang]

The dts file which you modified is for DPAA1 platform, for LX2160A(DPAA2) you need to modify the following device node in arch/arm64/boot/dts/freescale/fsl-lx2160a.dtsi

ptp-timer@8b95000 {
compatible = "fsl,dpaa2-ptp";
reg = <0x0 0x8b95000 0x0 0x100>;
clocks = <&clockgen 4 1>;
little-endian;
fsl,extts-fifo;
};

Modify the device node similar as the following:

ptp-timer@8b95000 {

                        compatible = "fsl,dpaa2-ptp";

                        reg = <0x0 0x8b95000 0x0 0x100>;

                        fsl,cksel       = <1>;

                           fsl,tclk-period = <10>;

                           fsl,tmr-prsc    = <10000>;

                           fsl,tmr-add     = <0xccccccccd>;

                           fsl,tmr-fiper1  = <9999990>;

                           fsl,tmr-fiper2  = <999990>;

                           fsl,tmr-fiper3  = <9999990>;

                           fsl,max-adj     = <249999999>;

                        little-endian;

                        fsl,extts-fifo;

                }; 

For these parameters configuration, please refer to Documentation/devicetree/bindings/ptp/ptp-qoriq.txt          

[wutianyi]

Hi  yipingwang:

      抱歉，截图错了。这个才是我们的设备树配置，和你给的参考配置一样。我尝试了各个版本的PTP4L开源代码，都有一样的问题。重启服务器的时候，发现ptp输出的1PPS会有一个相位跳变。我同事告诉我之前别的项目，在别的平台这种场景，PTP输出的PPS是缓慢变化的。我想知道这个是有啥配置我没有配置好，还是说2160的ptp的ip core有啥不一样。

谢谢

天易

[yipingwang]

Please configure dts file as the following

ptp-timer@8b95000 {

                        compatible = "fsl,dpaa2-ptp";

                        reg = <0x0 0x8b95000 0x0 0x100>;

                        fsl,cksel = <1>;

                           fsl,tclk-period = <10>;

                           fsl,tmr-prsc = <10000>;

                           fsl,tmr-add = <0xccccccccd>;

                           fsl,tmr-fiper1 = <9999990>;

                           fsl,tmr-fiper2 = <999990>;

                           fsl,tmr-fiper3 = <9999990>;

                           fsl,max-adj = <249999999>;

                        little-endian;

                        fsl,extts-fifo;

                }; 

You need to adjust parameters according to the description in Documentation/devicetree/bindings/ptp/ptp-qoriq.txt

[wutianyi]

感谢您的回复，我通过修改ptp4l的源码，解决了这个问题。有个逻辑 检测到没有报文之后会切换状态，然后输出本地时钟。先保存上次的状态，检测到没有报文的时候，不切换状态。这样就不会切换到本地时钟，看见效果就是重启服务器的时候 PTP失步但是出的PPS不会跳变。

[yipingwang]

Thanks for your update.