tree 45099b46d5dbd8ec955a4ee00165a3939858d96e
parent 565775f18b3ab77347d3f901d6894f676a861d08
author Philipp Wagner <phw@lowrisc.org> 1599072843 +0100
committer Philipp Wagner <mail@philipp-wagner.com> 1599129522 +0100

[otbn] Fix some issues in modexp assembly

The modexp assembly doesn't currently run on the new simulator. Some
problems are simulator-related, others are bugs in the code. I'm still
going through all of them, but here are two fixes which are clearly
wrong in the assembly.

* LW expects offsets in bytes, not in 32b words.
* In contrast to dcrypto1, routines need to end with an explicit ECALL
  instruction.

Signed-off-by: Philipp Wagner <phw@lowrisc.org>