On Mar 10, 2015, at 2:52 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Tuesday 10 March 2015 13:10:08 Kumar Gala wrote: >>>>>>>>>>> The top level qcom,msm-id and qcom,board-id are utilized by bootloaders >>>>>>>>>>>> on Qualcomm MSM platforms to determine which device tree should be >>>>>>>>>>>> utilized and passed to the kernel. >>>>>>>>>>>> >>>>>>>>>>>> Cc: <devicetree@xxxxxxxxxxxxxxx> >>>>>>>>>>>> Signed-off-by: Kumar Gala <galak@xxxxxxxxxxxxxx> >>>>>>>>>>> >>>>>>>>>>> Is this the special magic that allows qcom bootloaders to take a kernel >>>>>>>>>>> plus multiple DTBs and figure out which DTB to pass? >>>>>>>>>>> >>>>>>>>>>> Kevin >>>>>>>>>> >>>>>>>>>> yes >>>>>>>>> >>>>>>>>> That's a bummer. >>>>>>>>> >>>>>>>>> Luckily, the solution for upstream is still quite simple: Provide only >>>>>>>>> one devicetree, and it'll be used, right? >>>>>>>> >>>>>>>> We can provide only one, we still need the IDs in the DT. >>>>>>> >>>>>>> How are the DTS provided? Concatenated with the kernel, or in a >>>>>>> wrapped data format? Or in a separate partition from the kernel? >>>>>> >>>>>> Its a wrapped data format that is than concatenated with the kernel if I remember correctly. >>>>> >>>>> Then you should be able to create a tool that can write this concatenated >>>>> format and insert these properties from a table that matches the boot >>>>> loader, right? >>>>> >>>>> Arnd >>>> >>>> Are you suggesting the tool insert the properties in the DT? I’m not sure I understand what the point of doing that would be. >>> >>> To insert platform-local properties that mean nothing outside of the >>> firmware packaging of the device trees, which is the case here? >>> >>> I think the idea of having the installer script inserting them is >>> quite reasonable in this case. >>> >>> >>> -Olof >> >> These values are static, so not sure what the point of having the installer script do that? >> > > It combines two hacks to work around a nonstandard boot loader. > Once the bootloader is fixed, you can stop using that script. > > Arnd I feel as if I’m missing something here. If we just have the properties in the .dts files I don’t need to change anything ever, no script, no worries about working with old or new boot loaders, etc. - k -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- 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
