This series adds support for booting BE kernels from UEFI. As UEFI is defined to be strictly little endian, some workarounds are required to combine a little endian EFI stub with a big endian kernel. Also, runtime services need to be wrapped so they can be executed in little endian mode. Patches #1 and #2 have been sent to the list before, but are included for completeness. Patch #3, #4 and #5 modify the PE/COFF header definition so it is always emitted in little endian, regardless of the endianness of the kernel. Patch #6 removes references to linker defined symbols like _text and _edata from the stub, as the stub is now a standalone little endian binary that is wrapped in a big endian object file, and _text and _edata are unavailable or meaningless in that context. Patch #7 adds the Makefile changes and some code to build the standalone stub and wrap it. Patch #8 updates the kernel code that references data in UEFI memory to byte reverse it if required. Patch #9 adds runtime services wrappers for the variable store services so they can be called from the big endian kernel. Other runtime services are not implemented for now. Patch #10 enables everything by adding the Kconfig logic. This is tested on Foundation model and FVP Base model. Booting works fine on both, however, enumerating the variable store works only on FVP Base, and is not debuggable on Foundation Model, so I would really appreciate any insights into the code in patch #9 that may be causing this. There is some trickery regarding en-/disabling caches and MMU and surely I have gotten something wrong there. Ard Biesheuvel (10): arm64/efi: efistub: jump to 'stext' directly, not through the header arm64/efi: efistub: cover entire static mem footprint in PE/COFF .text arm64: add macros to emit little endian ASM constants arm64: add EFI little endian constants to linker script arm64/efi: update the PE/COFF header to be endian agnostic arm64/efi: efistub: avoid using linker defined constants arm64/efi: efistub: add support for booting a BE kernel arm64/efi: use LE accessors to access UEFI data arm64/efi: enable minimal UEFI Runtime Services for big endian arm64: Kconfig: enable UEFI on BE kernels arch/arm64/Kconfig | 10 ++- arch/arm64/include/asm/assembler.h | 18 +++++ arch/arm64/include/asm/efi.h | 2 + arch/arm64/kernel/Makefile | 7 +- arch/arm64/kernel/efi-be-call.S | 55 +++++++++++++++ arch/arm64/kernel/efi-be-runtime.c | 104 ++++++++++++++++++++++++++++ arch/arm64/kernel/efi-entry.S | 41 ++++++++--- arch/arm64/kernel/efi-stub.c | 11 ++- arch/arm64/kernel/efi.c | 68 +++++++++++------- arch/arm64/kernel/efistub-le/Makefile | 52 ++++++++++++++ arch/arm64/kernel/efistub-le/efi-le-entry.S | 13 ++++ arch/arm64/kernel/efistub-le/efistub-le.lds | 35 ++++++++++ arch/arm64/kernel/efistub-le/le.h | 12 ++++ arch/arm64/kernel/efistub-le/strstr.c | 20 ++++++ arch/arm64/kernel/head.S | 50 +++++++------ arch/arm64/kernel/image.h | 16 ++++- drivers/firmware/efi/efi.c | 26 ++++--- drivers/firmware/efi/efivars.c | 2 +- drivers/firmware/efi/libstub/fdt.c | 4 ++ 19 files changed, 466 insertions(+), 80 deletions(-) create mode 100644 arch/arm64/kernel/efi-be-call.S create mode 100644 arch/arm64/kernel/efi-be-runtime.c create mode 100644 arch/arm64/kernel/efistub-le/Makefile create mode 100644 arch/arm64/kernel/efistub-le/efi-le-entry.S create mode 100644 arch/arm64/kernel/efistub-le/efistub-le.lds create mode 100644 arch/arm64/kernel/efistub-le/le.h create mode 100644 arch/arm64/kernel/efistub-le/strstr.c -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
