I am completely confused about bitbake variables how and when to set them to get the desired result in the poky/yocto environment.
For context, I am just a user but I have been around awhile. I have been using yocto/poky for several years now. I have written a number of simple recipes and successfully deployed embedded linux builds on a number of custom projects and architectures (x86 x86_64 zync and alterasoc ). This stuff works. My hat is off to the architects.
The problem comes when I want to change something. Frankly, I dont understand the documentation. Its way too generic. I end up wandering around the recipes and web searching and trying everything until I find some seemingly random combination of bbappend or conf file or variable_name that works. Once found, it works no sweat, but there has to be a better way.
So here is an example of a problem I am trying to solve. I need to add a boot parameter to the kernel. When I run bitbake -v -f core-image-minimal for an x86 system I notice that (at least in the old version I am using) uses syslinux as the boot agent. So I look at syslinux it needs a file called syslinux.cfg. There is a parameter there called APPEND that I need to add the keyword to. Then I find the syslinux.cfg file in a yocto build and I see that its created by a python script inside of syslinux.bbclass. I look there and sure enough there is a big comment there telling me to set the APPEND variable for the class. I also notice that the python script that creates syslinux.cfg runs when I run bitbake -v -f core-image-minimal
Also in the documentation there is a class called syslinux and it lists the variables that I found in the comments bbclass file. This is no doubt some clever auto-doc feature.
But thats where it ends. How do I know how to set that APPEND variable for my custom build? The answer is either a bbappend file in my layer, a conf file, or something I can put in local.conf.
Rather than just telling me the answer, can someone please describe the reasoning that would go into figuring it out so I can figure out other similar issues on my own later? Or perhaps this was already done and I am missing some documentation somewhere. Can you please direct me? Thanks for your patience.
Jeff Hagen -- Jeffrey R Hagen Lithe Technology LLC jha...@lithetechnology.com (520) 488-1155 (mobile) (520) 477-6066 (office) http://www.lithetechnology.com -- _______________________________________________ yocto mailing list yocto@yoctoproject.org https://lists.yoctoproject.org/listinfo/yocto
