In fact, I think I have difficulties with glitches on the bus, but changes at the boards are much more expensive and time consuming - so I'll try to get a better stability with that gpio-bitbang driver.
Thanks Mike, especially for the hints with devicetree. Are this GPIO numbers are same as MIO-Pin-numbers? I found that the base-include for zynq has been changed completly (at least in my eyes), so it will take some time to adapt it to a new kernel. I created a new bitstream (IO set to GPIO instead of I2C) and (not sure whether it is required) a new fsbl. I don't need I2c in Uboot, but I am wondering where this gets information about it. Including driver in kernel is smallest issue. So altogether this becomes quite a project for me ;) but I hope I learn a lot with that. Did all this steps just once or twice some time ago. > Gesendet: Freitag, 05. April 2019 um 07:44 Uhr > Von: "Mike Looijmans" <[email protected]> > An: "Arno Steffens" <[email protected]> > Cc: "meta xilinx" <[email protected]> > Betreff: Re: Aw: Re: [meta-xilinx] Kernel version, xilinx git repo, yocto > kernel > > On 04-04-19 14:03, Arno Steffens wrote: > > Thanks Mike for this clear (and surprising) words. > > The reason I thought it might help is that functions like this > > (cdns_i2c_init_recovery_info) has been added. > > Well if you need recovery, something is broken on the bus... > > > I'll check the bitbang option. Do I have to expect performance/timing > > issues? > > I guess I have to adjust devicetree for that too? Phuuuuu. Thats always > > magic to me. > > Kind regards, Arno > > Here's our devicetree that sets up the bitbank stuff: > > https://github.com/topic-embedded-products/linux/blob/topic-miami/arch/arm/boot/dts/topic-miami.dtsi > > Don't forget to activate the bitbang GPIO I2C driver in the "drivers" section > of the kernel configuration as well. > > > > >> Gesendet: Donnerstag, 04. April 2019 um 07:31 Uhr > >> Von: "Mike Looijmans" <[email protected]> > >> An: "Arno Steffens" <[email protected]>, "meta xilinx" > >> <[email protected]> > >> Betreff: Re: [meta-xilinx] Kernel version, xilinx git repo, yocto kernel > >> > >> Simple solution would be to just stop using the cadence driver. There are > >> issues in the Zynq that cannot really be resolved in software apparently, > >> and > >> the only way around them we've found is to just use a bitbang GPIO > >> controller > >> on the same pins. That made all problems go away. > >> > >> Chances are that moving to a newer kernel will not resolve your I2C issues > >> anyway. > >> > >> On 03-04-19 13:53, Arno Steffens wrote: > >>> I need a more recent kernel (Zynq 7000) and wondering, what can I do. > >>> Why I am looking for that? > >>> I have I2C issues and guess I need the recovery functionality, but the > >>> Cadence I2c driver that supports it is only in the current xilinx master > >>> branch. Even not in mainline 4.19. > >>> > >>> Before this I2C issue popped up I took a kernel.org LTS kernel and > >>> patch/take over the qspi/dma stuff that I need from the xilinx kernel. > >>> But this time it will not work. What would you recommend me? > >>> > >>> Just take to master branch? That will probably never work with RT patches > >>> ... > >>> The xlx-kernel - Which kernel-org version it is based on? > >>> > >>> Best regards, Arno -- _______________________________________________ meta-xilinx mailing list [email protected] https://lists.yoctoproject.org/listinfo/meta-xilinx
