On Wednesday 04 March 2015 15:59:55 Chanwoo Choi wrote: > On 03/02/2015 06:22 AM, Arnd Bergmann wrote: > > On Saturday 28 February 2015 09:47:01 Chanwoo Choi wrote: > >> "earlycon=exynos4210,0x14C20000" is correct bootparam. You can check > >> it on Documentation/kernel-parameters.txt as following. > >> > >> exynos4210,<addr> > >> Use early console provided by serial driver available > >> on Samsung SoCs, requires selecting proper type and > >> a correct base address of the selected UART port. The > >> serial port must already be setup and configured. > >> Options are not yet supported. > >> > >> > > > > But it's crazy to do this when you have a DT. Please fix the existing > > devicetree files that use this to just list 'earlycon'. > > > > The syntax above only makes sense for classic board files that we > > do not support for exynos any more. > > Following earlycon patch for exynos soc was merged in Linux 4.0-rc1. > - commit-id: b94ba0328d3b36ff95f5074c0e9b44f90dc56bb5 (serial: samsung: Add support for early console) > Almost Exynos SoC use the same UART IP of Exynos4210. > > If you mean that "earlycon=exynos4210" naming will be changed to "earlycon=exynos", > we have to modify the drivers/tty/serial/samsung.c. No, what I mean is that you should use just "earlycon" instead of "earlycon=..." when you have a DTB. You have the OF_EARLYCON_DECLARE() in the driver as well, so that should just work. EARLYCON_DECLARE() is really just a hack that allows users to override the early console from the command line without modifying the stdout-path property. Don't put that into a dts file. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
