On Wed, Oct 14, 2015 at 9:48 AM, Daniel Walker <danielwa@xxxxxxxxx> wrote: > > > There's one last little wrinkle .. In the current setup the defconfig > CONFIG_CMDLINE="" is used as a default in case the device tree has nothing > in it. In my changes, there is no identical functionality. The only similar > thing I have is the the CONFIG_CMDLINE_APPEND="" . The main difference is > that in the current implementation CONFIG_CMDLINE="" doesn't get added at > all if there is a device tree bootargs, but with my implementation this line > would be added unconditionally. It would represent a subtle change where > people would have to add into the DT bootargs something to override what > might be in the default command line. So CMDLINE_EXTEND would be equivalent to your version, but it looks like CMDLINE_EXTEND is not used in the DT case. Perhaps you can add the option? You already have OVERRIDE which is equivalent to FORCE. > For example, > > if a config has CONFIG_CMDLINE_APPEND="debug" then they would have to add a > "loglevel=7" into the DT bootargs to get back to normal. I wouldn't think > people would want "debug" as the default, but oddly enough some of the > configs do have this. Some of them also have default ip address setting, > nfsroot= settings, and loglevel= settings. Or they would have to remove the kernel default from their config. That might be acceptable. You could have a case where you have 1 kernel binary and 2 different bootloaders where you expect the bootloader's cmdline used in one case and the kernel's in the other. Seems unlikely, but it would be an ABI break. I would not judge people's choices of defaults making sense... > What are your thoughts on this ? I think using the append type default makes > more sense because it's actually setting up global defaults. The current > complete replacement scheme seems to set the stage for people to make an > entirely custom default for a single development machine, which IMO doesn't > make sense. However, I'm not sure what the intent is with the current setup. People will want a path to support up to the current 3 options (use bootloader's cmdline, append bootloader cmdline to default, and force kernel default) and you have to assume changing bootloader is not an option. Rob > > Daniel > -- > 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 -- 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
