On Thu, 6 Apr 2017 06:12:16 +0100 Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
ok so the story goes like this:
back in august 2016 i got the A20 card up and running with mainline 4.7rc1 (or thereabouts), including patching in NAND support for a proper mtd device. it worked... up to a point... except when u-boot did a complete scan it CORRUPTED the NAND flash... just from reads.
i figured this was "just software" as it's pretty experimental, and the 3.4.104 sunxi-nand works perfectly.
fast-foward to a few months ago, when i was testing the external micro-sd slot, weirdly it resulted in a kernel segfault *from the sunxi-nand driver*. i thought, "that's weird, might be to do with current-fighting from the micro-desktop PCB not having level-shifting"
sooo... that's now fixed: the micro-sd slot works perfectly through the new revision 1.7 microdesktop's level-shifting IC. however i got exactly the same kernel segfault in the sunxi-nand driver, so i temporarily took it out of the kernel config, tested again, and yes, the micro-sd worked fine.
... except that when i booted it up again, the nand flash had been corrupted. now, bear in mind there's *NO DRIVER INSTALLED*.
this is just too weird for me to deal with. not to mention, because of the age of the A20's Boot ROM there is now a limited set of "legacy" NAND ICs available i've had it with them.
<snip>
I'm sorry to hear you are having trouble. Personally, I like the super weird Linux problems. Can I have one of those malfunctioning alpha boards to try to figure out what's going on? I grant you that I've never worked on something quite this low level before, so I won't be solving it any time soon, but it would be worth looking into just so that we don't have this problem again (yes, I would like to learn how to create SBCs).
Thanks, David
--- crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68
On Tue, Apr 18, 2017 at 10:22 PM, doark@mail.com wrote:
On Thu, 6 Apr 2017 06:12:16 +0100 Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
ok so the story goes like this:
back in august 2016 i got the A20 card up and running with mainline 4.7rc1 (or thereabouts), including patching in NAND support for a proper mtd device. it worked... up to a point... except when u-boot did a complete scan it CORRUPTED the NAND flash... just from reads.
i figured this was "just software" as it's pretty experimental, and the 3.4.104 sunxi-nand works perfectly.
fast-foward to a few months ago, when i was testing the external micro-sd slot, weirdly it resulted in a kernel segfault *from the sunxi-nand driver*. i thought, "that's weird, might be to do with current-fighting from the micro-desktop PCB not having level-shifting"
sooo... that's now fixed: the micro-sd slot works perfectly through the new revision 1.7 microdesktop's level-shifting IC. however i got exactly the same kernel segfault in the sunxi-nand driver, so i temporarily took it out of the kernel config, tested again, and yes, the micro-sd worked fine.
... except that when i booted it up again, the nand flash had been corrupted. now, bear in mind there's *NO DRIVER INSTALLED*.
this is just too weird for me to deal with. not to mention, because of the age of the A20's Boot ROM there is now a limited set of "legacy" NAND ICs available i've had it with them.
<snip>
I'm sorry to hear you are having trouble. Personally, I like the super weird Linux problems. Can I have one of those malfunctioning alpha boards to try to figure out what's going on? I grant you that I've never worked on something quite this low level before, so I won't be solving it any time soon, but it would be worth looking into just so that we don't have this problem again (yes, I would like to learn how to create SBCs).
sure - once i have working prototypes to replace it with.
l.
arm-netbook@lists.phcomp.co.uk
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doarkļ¼ mail.com -
Luke Kenneth Casson Leighton