Dear Sean,
when trying to run grubriscv64.efi from the trini/u-boot-gitlab-ci-runner:bionic-20200526-18Jun2020 Docker image on a MAIXDUINO the relocations are not naturally aligned:
lib/efi_loader/efi_image_loader.c(133) efi_loader_relocate():
efi_reloc 000000008030a000, offset 0x101e, type 10
Here we are trying to change an u64 at 0x8030B01E:
uint64_t *x64 = efi_reloc + offset; *x64 += (uint64_t)delta;
This leads to an exception in function efi_loader_relocate():
Unhandled exception: Load address misaligned EPC: 00000000805a95ac RA: 00000000805a953a TVAL: 000000008030b01e EPC: 000000008001c5ac RA: 000000008001c53a reloc
The GRUB image is available here:
https://gist.github.com/xypron/522a91962248e9c3888d8554cb61ad2c/raw/b9596616...
On QEMU the GRUB image is executed without problems:
https://gitlab.denx.de/u-boot/custodians/u-boot-efi/-/jobs/132919
The UEFI specification requires for the ARM platform that unaligned support is enabled. This is why we have implemented function allow_unaligned().
On RISC-V we have not yet implemented allow_unaligned() yet. Is there a way to switch RISCV64 CPUs especially the Kendryte K210 into a mode supporting unaligned access?
Best regards
Heinrich