IRC #olimex 2019-10-20

[02:17:40] <dongcarl> Hi all! I'm interested in the OLinuXino line of boards... Which one is the flagship product right now? The A64? Do these boards work with vanilla distros? Or are mods required?
[02:40:03] <jo0nas> dongcarl: The most "flagship'ish which works best with vanilla distros is LIME2 in the _oldest_ revision
[02:40:59] <dongcarl> jo0nas: Which variant is the oldest revision?
[02:41:54] <jo0nas> On Debian (which I consider a quite "vanilla" distro) newer boards require slight tinkering with custom bootloader: the newer rev. G2 alternatively need to be lowered to 1mbit ethernet, and the newest rev. K needs to be lowered to 10Mbit
[02:43:49] <dongcarl> jo0nas: Forgive me ignorance but I'm not seeing these revision numbers on the website, where might I locate them?
[02:43:52] <jo0nas> they don't list which revision is sold, so I guess you will need to ask explicitly - but I believe that if you pick a LIME2 variant with eMMC then it can only be rev. G or K, and if you pick one with flash then it can only be rev. K
[02:44:43] <jo0nas> I suggest simply write an email and ask - they are quite friendly!
[02:44:55] <dongcarl> jo0nas: Ah, thank you!
[02:45:11] <jo0nas> ...or buy whatever - but then just beware that you will need a bit of tinkering
[02:45:59] <jo0nas> the A64 board is indeed newer and faster - but is a different form factor which does not fit in the boxes that are sold, and is less well integrated with vanilla distros
[02:46:42] <dongcarl> Gotcha, very good to know!
[02:47:35] <jo0nas> if you don't need racing speed ethernet, then you should be fine even if the board you buy turns out to be a newer revision: Simply setup your system to lower the ethernet speed and in my experience it then works fine even with the classic compiled bootloader
[02:48:06] <jo0nas> i.e. very minor tinkering needed
[02:48:40] <jo0nas> ..and if you do figure out the bootloader tinkering then it should work flawlessly also with newer revisions
[02:49:21] <dongcarl> jo0nas: Huh... Do you have links for what the bootloader tinkering looks like?
[02:49:32] <jo0nas> the issue is that the newer revisions changed a chip, and the code distributed most widely does not take that into account, so wrongly calibrates the ethernet PHY (as I understand it)
[02:51:32] <jo0nas> the tinkering involves (grabbing a pre-built bootloader from somewhere that compiles optimized for specific boards - e.g. from Olimex themselves or maybe Armbian, or) fetch the mainline U-boot sources, configure it, with one single line changed to adjust the ethernet calibration, and compile it
[02:52:49] <dongcarl> jo0nas: Is this it: https://raw.githubusercontent.com/OLIMEX/OLINUXINO/master/SOFTWARE/A20/A20-build-3.4.103-release-7/BUILD_DESCRIPTION_A20_Olimex_kernel_3.4.103%2B_Jessie_rel_6.txt
[02:53:36] <jo0nas> https://bugs.debian.org/927397 tracks _one_ of the issues
[02:55:08] <dongcarl> Thank you!
[02:55:47] <jo0nas> the U-boot fix for rev. G2 boards is "TX_DELAY=4" - for the rev. K boards it is "TX_DELAY=3"
[02:57:11] <jo0nas> the rev. G2 issue is most widely discussed - both because that is an older board, but also because the FreedomBox project (which is a Debian-based project) uses that board and have worked with Olimex to fix that with minimal derivation from Debian
[02:58:40] <dongcarl> jo0nas: Yeah I've been seeing so much talk about the FreedomBox project... I wonder if they have a big user base though
[02:59:37] <jo0nas> passing "TX_DELAY is as I understand it found by simple trial-and-error - the better fix is to apply a patch to U-boot that decides which exact chip a board has by probing some board information
[03:00:44] <jo0nas> ...but noone has done a minimal patch yet (if they had - and I knew about it - then I would make sure the patch got applied in Debian officially!)
[03:01:51] <jo0nas> what exists is Olimex fork of U-boot with a more involved patchset to organize the whole line (or at least the 32bit models) of OlinuXino more homogenously
[03:02:19] <jo0nas> ...but that fork seems to not be actively pushed into mainline U-boot (at least yet)
[03:15:53] <dongcarl> Yeah sounds like some upstreaming needs to be done