Xalius

Moderator edit (pfeerick): I have modified this post to contextualise this split thread. It was initially intended to be a discussion of a board bring up procedure / proposal format, and has since evolved into discussion of the rock64 generally. Xalius originally said in this post: TODO-List sounds good to me, I will run some tests as soon as China Post/DHL actually deliver my package. I get a 4GB version with the suppressor diodes for USB3 already replaced... This is what tkasier originally wrote in his first post, minus the disclaimer as was only relevant to that thread:

I have not heard back yet from TL regarding XPowers looking into the issue with the battery charger, and I pretty much would like to see the ARISC code by now since working around that black box is rather frustrating. For now I changed my UPower settings to shutdown at 4% and the default action to 'poweroff' instead of 'hibernate' to avoid issues...

The protection circuit specs are in the battery datasheets which are already on the Pine wiki. The UVLO voltages for are around 2.7-2.8V and should be well below those set in the AXP. I still have a suspicion that whatever happens, it has something to do with running out of battery in suspend. Under normal load the battery cuts out well above 3.0V , I saw values around 3.2-3.4V in my tests....

Question, how did it run dry? Was that with system active or did it run dry in suspend? Maybe the ARISC does weird things and leaves the AXP in some faulty state... just a wild guess, I tried to discharge my PB a couple times now and couldn't get it into that state so far... I even disabled upower once and let it run until the kernel crashed, that was around 3.4V at 2A load and well past 2% capacity left... but even after that it came back fine and just charged the battery....

Yeah I think there might be a bug somewhere in that u-boot power state handling code. One thing I noticed while I did my battery life test a while back is also that with the current u-boot we have on the Pinebook images, it does not run just with DC power and without a battery like the Pine64 does... so maybe those issues are somehow connected...

If I would have to take a potshot I would maybe start trying with setting both undervoltage lockouts below 3.0V in the u-boot dts, then disconnect the battery from the AXP to reset it's registers and see if that changes anything... but there should be no connection between undervoltage lockout (prevents AXP from turning on) and the charger, since we see u-boot displaying the red battery bitmap apparently... which means the AXP turns on fine...

We do not have an Errata sheet for the AXP803, do we? Maybe it has to d!)o something with the undervoltage lockout settings in the dts..., but that would be silly, or a bug... As far as I understand the datasheet, there is only two states for the charger to be in if it is enabled, and that is more or less hardwired. Under 3.0V it charges slowly with 1/10 of the programmed normal current (which doesn't seem to happen either) and above 3.0V it should charge with the programmed online/offline charge current... maybe there are some fault conditions that get triggered that turn it off... but I haven't found anything in the datasheet yet to explain the behavior and didn't manage to trigger it myself yet... As for recovery I would try to manually charge the LiPo a bit with a bench lab supply, set some save end voltage like 4.0V and current limit to 2A and just hold some test probe to the terminals (disconnect from PCB first!) for a couple minutes, that should get it back up enough if it is an undervoltage problem

There is a switch to limit Chromium's disk cache size: --disk-cache-size=n n in Bytes, I use 300MB atm...