On Thu, Mar 5, 2015 at 10:03 PM, Robert P. J. Day <rpj...@crashcourse.ca> wrote: > > in section 3.2 of the kernel dev manual, there is a discussion of > KMACHINE and how it is *typically* set to the same value as MACHINE, > but there are cases where that might not be true; however, the example > used to demonstrate this -- emenlow and emenlow-noemgd -- doesn't seem > appropriate as there is no "emenlow" machine definition file anymore > in meta-intel. AFAICT, all of those non-noemgd machine definitions are > gone. > > in all the layers i have checked out, the only layer where i see > KMACHINE covering a number of MACHINE values is meta-xilinx > (zynq-based machines). it sounds picky but, when demonstrating some > concept, i think it's important that examples used actually exist in > the code base in case people want to check.
It comes around a bit due to the nature of different types of hardware. You will find that amongst most of the meta-* bsp layers there exists two types of MACHINE. You have the layers like meta-xilinx, meta-ti, etc which have machines for each board. And then there are the layers like meta-intel which have machines for each platform or SoC. There are a number of reasons for each way. At least for Zynq, the kernel can (if you ignore that it has FPGA logic) be configured and built the same way for all the boards with device trees handling the differences. And as such the configuration is setup for the SoC instead of the board. The reason that you actually see KMACHINE differences in meta-xilinx is that the layer uses the linux-yocto build flow as well as providing an in layer config cache for its targeted KMACHINE's. Which I believe is rarely done in bsp layers that inherit linux-yocto for their kernels (or bbappend to linux-yocto). You could re-word the documentation to cover this case with something like: "This variable is typically set to the same value as the MACHINE variable however in some cases may instead refer to the underlying platform of the MACHINE." Regards, Nathan > > rday > > -- > > ======================================================================== > Robert P. J. Day Ottawa, Ontario, CANADA > http://crashcourse.ca > > Twitter: http://twitter.com/rpjday > LinkedIn: http://ca.linkedin.com/in/rpjday > ======================================================================== > -- > _______________________________________________ > yocto mailing list > yocto@yoctoproject.org > https://lists.yoctoproject.org/listinfo/yocto -- _______________________________________________ yocto mailing list yocto@yoctoproject.org https://lists.yoctoproject.org/listinfo/yocto