On Mon, Apr 4, 2022 at 12:01 PM Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Mon, Apr 4, 2022 at 7:57 PM Max Filippov <jcmvbkbc@xxxxxxxxx> wrote: > > Please let me know if you observe any specific build/runtime issues. > > This is what I get: > > $ make ARCH=xtensa O=build/xtensa nommu_kc705_defconfig vmlinux V=1 > .... > xtensa-linux-gcc-11.1.0 -DKCONFIG_SEED= ... > /git/arm-soc/arch/xtensa/kernel/head.S: Assembler messages: > /git/arm-soc/arch/xtensa/kernel/head.S:87: Error: invalid register > 'atomctl' for 'wsr' instruction Sure, one cannot use an arbitrary xtensa compiler for the kernel build, the compiler configuration must match the core variant selected in the linux configuration. Specifically, for the nommu_kc705_defconfig the following compiler can be used: https://github.com/foss-xtensa/toolchain/releases/download/2020.07/x86_64-2020.07-xtensa-de212-elf.tar.gz If you build the toolchain yourself using crosstool-ng or buildroot they accept the 'configuration overlay' parameter that does the compiler customization. Perhaps the documentation for this part is what needs to be improved. > I think there were other errors in the past, but every time I tried > it, the build failed for me. -- Thanks. -- Max
