On Fri, 15 Nov 2019 at 09:30, Hui Wang <[email protected]> wrote: > > I did test with VMSPLIT_2G today, the mmc/sd controller will not work > anymore on rpi4 boards, so enable VMSPLIT_2G is not a solution so far.
Oh well, was worth a try. > And today I also tested dwc2, it worked well, maybe we could enable dwc2 > instead of dwc_otg, then we could use a single kernel to support > rpi2/3/4. dwc2 worked well both with VMSPLIT_2G and VMSPLIT_3G. Interesting; I noted upstream talking about the optimization of dwc_otg (I'm guessing, from a quick skim of each, that's mostly from the FIQ FSM stuff in dwc_otg which dwc2 seems to lack); we should probably benchmark the performance differences between dwc_otg and dwc2, both USB transfer speeds, and load on the ARM during transfers (my hunch is, if anything is affected, it'll be the latter - I vaguely recall forum posts about improvements on the ARM load during large USB transactions). > I am building a formal armhf and arm64 kernel with dwc2 enabled, will > test all kernels on all boards. And I will share the kernels to the lp, > anyone could help test them. Given arm64 isn't affected, would it be worth sticking with dwc_otg on that arch? Or is the inconsistency (e.g. different capabilities?) an issue in and of itself? I'm more than happy to test out some kernels when they're available! Thanks, Dave. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1852510 Title: IO errors when writing large amounts of data to USB storage in eoan on RPI To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-raspi2/+bug/1852510/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
