[LinuxPPS] LinuxPPS + kernel 2.6.34 = ok

[Udo van den Heuvel]

On 2010-05-24 09:47, Udo van den Heuvel wrote:
> # cat /sys/devices/virtual/pps/pps0/{assert,clear}
> 1274686950.992846869#955
> 1274686008.261192728#12
> 
> I.e.: clear edge get stuck when ntpd is started.

Same results after restart of ntpd using ppstest:
# ./ppstest /dev/pps0
trying PPS source "/dev/pps0"
found PPS source "/dev/pps0"
ok, found 1 source(s), now start fetching data...
source 0 - assert 1274687389.013140132, sequence: 90 - clear
1274687310.183775587, sequence: 11
source 0 - assert 1274687390.013351079, sequence: 91 - clear
1274687310.183775587, sequence: 11
source 0 - assert 1274687391.013555265, sequence: 92 - clear
1274687310.183775587, sequence: 11
source 0 - assert 1274687392.013764126, sequence: 93 - clear
1274687310.183775587, sequence: 11
source 0 - assert 1274687393.013945705, sequence: 94 - clear
1274687310.183775587, sequence: 11
source 0 - assert 1274687394.014124744, sequence: 95 - clear
1274687310.183775587, sequence: 11
source 0 - assert 1274687395.014307741, sequence: 96 - clear
1274687310.183775587, sequence: 11

Even worse, ppstest causes the same issue as ntpd:
[root at epia pps-tools]# killall -9 ldattach
[root at epia pps-tools]# ldattach 18 /dev/ttyS0
[root at epia pps-tools]# cat /sys/devices/virtual/pps/pps0/{assert,clear}
1274687503.026720815#2
1274687503.226737226#2
[root at epia pps-tools]# cat /sys/devices/virtual/pps/pps0/{assert,clear}
1274687504.026802913#3
1274687504.226816875#3
[root at epia pps-tools]# cat /sys/devices/virtual/pps/pps0/{assert,clear}
1274687505.026878933#4
1274687504.226816875#3
[root at epia pps-tools]# cat /sys/devices/virtual/pps/pps0/{assert,clear}
1274687505.026878933#4
1274687505.226894221#4
[root at epia pps-tools]# cat /sys/devices/virtual/pps/pps0/{assert,clear}
1274687506.026958612#5
1274687506.226965124#5
[root at epia pps-tools]# cat /sys/devices/virtual/pps/pps0/{assert,clear}
1274687506.026958612#5
1274687506.226965124#5
[root at epia pps-tools]# cat /sys/devices/virtual/pps/pps0/{assert,clear}
1274687507.027036766#6
1274687507.227048835#6
[root at epia pps-tools]# ./ppstest /dev/pps0
trying PPS source "/dev/pps0"
found PPS source "/dev/pps0"
ok, found 1 source(s), now start fetching data...
source 0 - assert 1274687510.027263856, sequence: 9 - clear
1274687509.227200490, sequence: 8
source 0 - assert 1274687511.027340769, sequence: 10 - clear
1274687509.227200490, sequence: 8
source 0 - assert 1274687512.027419490, sequence: 11 - clear
1274687509.227200490, sequence: 8
source 0 - assert 1274687513.027494194, sequence: 12 - clear
1274687509.227200490, sequence: 8
source 0 - assert 1274687514.027567807, sequence: 13 - clear
1274687509.227200490, sequence: 8

How can I fix this?

Udo