* Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> [140902 11:40]: > On 09/01/2014 07:47 PM, Sebastian Andrzej Siewior wrote: > > Comparing it with serial-omap I see the same thing: I takes approx the > > same amount of data until the first one is displayed. After a lot of > > "long" writes which wake the chip up from idle I manage to freeze both, > > the serial-omap driver and mine driver. > > So after some testing: > - it happens with omap-serial as well. Especially after disabling the > LED trigger for both LEDs. > > - it seemed that disabling the MDR1 check whether or not we lost > context made the problem appear less often but it was a trick. Even > with restoring the context each time I see the same problem. > > - it seems to be easier to trigger with the LED trigger switched off. > However sometimes it works for 10 minutes, sometimes it triggers > after one. > > - I see to face two kind of "deaths": > - the LED still goes on and off and the uart just does not respond > even if I tell the button print something on the screen (the button > also changes the frequency of the LED so I know that the button is > doing something). > Also from dumping the content of /proc/interrupts it seems that a > wake up is made, the uart should have restored the registers. OK yeah this is the case I was seeing too. So do you just set the LED triggers to none in sysfs to make it easier to reproduce? > - one where the system is dead and the LED does not blink anymore. > Also my button is dead. This I don't think I've seen. This could also be the errata issue on your earlier rev beagleboard-xm with off-idle. > - disabling DMA makes the problem not go away. OK > - mdelay(25) in omap8250_lost_context() is long enough to drop the 403 > bytes I send in my testcase. That means I see only "good" characters. > With this the box remained alive for 2h. However the uart died anyway. I wonder if doing some TX on the uart restores it? So maybe try $ while [ 1 ]; do date; sleep 10 done & To have it occasionally print something in the background. Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
