arch/riscv: Refactor bootblock.S

A few things are currently missing:
- The trap handler doesn't set the stack pointer, which can easily
  result in trap loops or memory corruptions.
- The SBI trampolin page (as described in version 1.9 of the RISC-V
  Privileged Architecture Specification), has been removed for now.

Change-Id: Id89c859fab354501c94a0e82d349349c29fa4cc6
Signed-off-by: Jonathan Neuschäfer <>
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <>
3 files changed