On Tue, Jun 03, 2014 at 03:35:39PM +0100, Pacman du34 wrote: > 2014-06-03 15:35 GMT+02:00 Mark Rutland <mark.rutland@xxxxxxx>: > > On Tue, Jun 03, 2014 at 02:25:25PM +0100, Pacman du34 wrote: > >> 2014-06-03 15:02 GMT+02:00 Mark Rutland <mark.rutland@xxxxxxx>: > >> > On Tue, Jun 03, 2014 at 01:53:24PM +0100, Pacman du34 wrote: > >> >> Hello all, > >> >> > >> >> I am working on a new Linux port to a new architecture and I would like > >> >> to add a dts file to describe my system. > >> >> > >> >> So first of all I wrote the following dts test file : > >> >> > >> >> / { > >> >> compatible = "manufacturer,cpu"; > >> >> }; > >> >> > >> >> I've read that this is the minimum structure required for a device tree > >> >> on the wiki. > >> >> > >> >> But when I try compiling it with dtc (the first line is the command > >> >> line) I get this error message : > >> >> > >> >> dtc -I dts -O dtb -o my_file.dtb myfile.dts > >> >> > >> >> Error: myfile.dts:1.1-2 syntax error > >> >> FATAL ERROR: Unable to parse input tree > >> > > >> > You're missing the DTS version. Try: > >> > > >> > /dts-v1/; > >> > / { > >> > comaptible = "manufacturer,device"; > >> > }; > >> > > >> > Cheers, > >> > Mark. > >> > > >> >> > >> >> I tried both the dtc version of Linux source code (1.2.0-g37c0b6a0) and > >> >> dtc version installed with "apt-get install device-tree-compiler" (1.3.0). > >> >> > >> >> I searched on Google but I have not found relevant information for my issue. > >> >> > >> >> I really do not understand what the problem here and I am totally stuck. > >> >> Any help will be appreciated. > >> >> > >> >> Thanks a lot in advance. > >> >> > >> >> Best regards. > >> > >> That works, thank you very much, > >> > >> I take this opportunity to ask another question... As I have to > >> specify the DTS version, are there other versions, and if yes, what > >> are their differences ? I mean, if there are other versions, why to > >> choose the vesion 2 instead of 3 or 1 ? > > > > There was a v0 a while back according to ePAPR, but it's obsolete, > > incompatible and no-one uses it anymore (dtc doesn't support it as far > > as I can tell). The flag is to tell v1 apart from v0. > > > > There is not currently a v2 or later. Perhaps there might be in future, > > so it's worth keeping the flag around, but at present there's > > effectively only v1. > > > > Cheers, > > Mark. > > Ok thank you very much again for your quick answer. > > So I'll keep using v1 flag. > > At the beginning of the porting, I was using a kernel version which > does not support Device Tree, I only had a C file to initialize the > drivers for my board. And I'm trying to understand how to add the > support of Device Tree to the kernel. Because now I have a dtb file, > but no message appears during the boot, showing that the kernel knows > it must read this file and use the matching device drivers. > > I have seen that some manufacturers use "config USE_OF", in the > Kconfig file, to give the option to add device tree support when > compiling the kernel. So I added the same option, but I don't know how > to confirm that the kernel is now using device tree. > > Will it appear some messages, during boot, that indicate the kernel is > really using it ? That would all be up to your architecture code. I'm afraid I can't really help with debugging architectural bringup. I can only recommend that you look through what other architectures do as part of their boot sequence, and do something along those lines. Cheers, Mark. -- 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