On Sat, May 19, 2018 at 6:51 PM, Gedare Bloom <ged...@rtems.org> wrote: > On Fri, May 18, 2018 at 5:53 PM, Joel Sherrill <j...@rtems.org> wrote: >> >> >> On Fri, May 18, 2018 at 3:24 PM, Amaan Cheval <amaan.che...@gmail.com> >> wrote: >>> >>> Hi everyone! >>> >>> I've written a quick blog post summarizing the options I've considered >>> to make the x86_64 port work with UEFI firmware - the primary winner >>> seems to be in my eyes to use "gnu-efi" and to add support for the >>> target "pei-x86-64" (aliased to "efi-app-x86_64") to >>> "x86_64-rtems5-objcopy" in binutils. I've submitted a patch for this >>> here[1]. >> >> >> That patch is quite simple so shouldn't be a problem if this is the >> direction >> that gets consensus. >>> >>> >>> The blog post is here: >>> https://blog.whatthedude.com/post/uefi-app-options/ >>> >>> I'd appreciate all feedback (and please do let me know if I haven't >>> provided enough context)! >>> >>> Specifically, some concerns I'd like to discuss are: >>> >>> - Does everyone agree with me on choosing gnu-efi + objcopy as our >>> method of choice? >> >> >> Does using gnu-efi add code that runs on the target? Can you point >> us to the files, if so.
Sure. The files would run on the target, yes. These are the ones listed here (as linked to in my blog post, perhaps without sufficient emphasis): https://wiki.osdev.org/UEFI#Developing_with_GNU-EFI >> >> Can you tell which approach FreeBSD takes? FreeBSD takes the gnu-efi approach I see as the "winner" here (also a link in the post): https://github.com/freebsd/freebsd/blob/996b0b6d81cf31cd8d58af5d8b45f0b4945d960d/stand/efi/loader/Makefile#L98-L119 >> >>> >>> - How do we integrate gnu-efi into our build process? A part of the >>> RSB, making sure the path to the libraries are in an exported >>> variable? Or perhaps a part of the RTEMS kernel itself if the licenses >>> are compatible (I don't see any on the project[2], only copyright >>> notices within the source files of the release versions). >> >> >> GNU-efi would be built like qemu or the device tree compiler would >> be my guess and x86_64-rtems toolset might add that to the standard >> set of tools. License on host tools being GPL isn't an issue. >> > > It appears to be a standard 2-clause BSD released by Intel as > specified in the README file of gnu-efi. > >> >>> >>> - Regardless of how we manage UEFI, do we require Multiboot support >>> too? Multiboot drops us in a 32-bit protected mode environment, >>> whereas 64-bit UEFI firmware will boot us into 64-bit long mode - this >>> would mean the kernel would need to support separate code-paths for >>> the 2 if we want to support both methods. >> >> >> That's a good question. For GSoC, I think UEFI is fine and perhaps a ticket >> under the general "modern PC support" ticket for multiboot support. Unless >> that eliminates a LOT of PCs. >> >> I don't want you to spend all summer getting an image to boot both >> ways. Personally, I want you to have a working BSP one way. :) > +1 > Noted, thanks! >>> >>> >>> [1] https://www.sourceware.org/ml/binutils/2018-05/msg00197.html >>> [2] https://sourceforge.net/projects/gnu-efi/ >> >> >> --joel >> >> _______________________________________________ >> devel mailing list >> devel@rtems.org >> http://lists.rtems.org/mailman/listinfo/devel _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
