Premi, Sanjeev wrote, on 11/09/2010 02:48 AM: >> >> Peter Barada wrote, on 11/05/2010 11:59 PM: >>> Personally I'd like to see the kernel and u-boot disconnect on the >> >> Looks like we are getting to a consensus - we all seem to dislike the >> dependency of u-boot and kernel for mux as of today - can we >> think about > > [sp] In my opinion, we need to do minimal and necessary MUX settings > in u-boot and let kernel manage itself. > > This also helps ensure that problems noticed in kernel are easy > to replicate on other similar platforms. Last year I spent long > time in convincing that wake-up on keypad was not working in Linux > kernel; but folks using OMAP3430SDP maintained it worked fine. > Root cause - relevant PADCONF was set in u-boot for 3430SDP. > (not quoting mail-chain) > > We may not be able to eliminate such instances altogether - but > can have less of such instances. I definitely agree.
> >> post 2011March as a good time to start pushing the relevant >> changes in? >> if that is the case, I will start posting RFCs in the coming weeks so > > [sp] Can you list what chanages you are trying to propose? ...without > going as far as RFC. > > the mails quoted in previous message are again too long and wide > in discussion. A concise list will help. Have'nt got to the code yet - had no intent of spending those cycles if the community had no interest in it and without a potential date OR had some issue which I could not think about. but anyways, here is the overall idea: per Soc, have muxes per IP - I did not think it was worthwhile to do a complex mux (dynamic) as done in linux kernel. DDR_CS0_MUX DDR_CS1_MUX GPMC_MUX -> need to think an elegant method to specify CSs to enable I2C{1,2,3,4,5 - based on SoC}_MUX MMC{0,1,2,3,4- based on SoC}_MUX UART{0,1,2,3,4 - based on SoC}_MUX If bootlogo enabled DSS_PARALLEL_MUX DSS_DSI_MUX if USB OTG enabled USB_OTG_MUX if USB Host enabled USB_EHCI_MUX GPIO Muxes -> need some elegant way to specify which GPIOs map to which muxed pins.. if SPI enabled, SPI_MUX None of the muxing will be wakeup enabled -> wakeup is a kernel feature and should be done there. only mux mode and pull types should be set in u-boot. The board file will still call the mux -> it will however only call the ones it needs to boot and load image. One more additional thought I had was to introduce Mux Scheme per IP -> e.g. DSS lines come out in different pin sequences -> we call each SCHEMEs so that new boards can find it a little easier to enable MUX.. -- Regards, Nishanth Menon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot