[otbn] Remove stale TODO in sim hjson
As Sri pointed out, there's a simple way to point tests at a different
directory of binaries. Remove the TODO and add a comment explaining
how to do so.
Also get rid of the intermediate "otbn_elf_dir" variable: it's not
needed otherwise, and we don't want anything else to use it (because
that wouldn't play well with the plusargs override).
Signed-off-by: Rupert Swarbrick <rswarbrick@lowrisc.org>
diff --git a/hw/ip/otbn/dv/uvm/otbn_sim_cfg.hjson b/hw/ip/otbn/dv/uvm/otbn_sim_cfg.hjson
index 0157e9c..49b93b5 100644
--- a/hw/ip/otbn/dv/uvm/otbn_sim_cfg.hjson
+++ b/hw/ip/otbn/dv/uvm/otbn_sim_cfg.hjson
@@ -53,12 +53,11 @@
uvm_test: otbn_base_test
uvm_test_seq: otbn_base_vseq
- // The directory where ELF binaries should be found.
- //
- // TODO: This needs deciding upon. Eventually, it might be nice to allow this
- // to be overridden on the command line ("I've got a bunch of ELF files
- // that stress my new feature; please run the test suite with them")
+ // The default place to find and build ELF binaries. If you have
+ // some pre-built binaries, you can run the simulation with them by using
+ // --run-opts to override the otbn_elf_dir plusarg in run_opts.
otbn_elf_dir: "{run_dir}/build-out"
+
run_opts: ["+otbn_elf_dir={otbn_elf_dir}"]
// OTBN run modes.
