[otbn,dv] Configure URND EDN connection to respond faster
This makes a significant difference to total run time. A
representative otbn_multi run took around 191us of simulated time
before this change and only 121us afterwards.
Signed-off-by: Rupert Swarbrick <rswarbrick@lowrisc.org>
diff --git a/hw/ip/otbn/dv/uvm/env/otbn_env_cfg.sv b/hw/ip/otbn/dv/uvm/env/otbn_env_cfg.sv
index 0c84d02..cb9076a 100644
--- a/hw/ip/otbn/dv/uvm/env/otbn_env_cfg.sv
+++ b/hw/ip/otbn/dv/uvm/env/otbn_env_cfg.sv
@@ -105,6 +105,12 @@
// values, in case of a TL fault.
tl_intg_alert_fields[ral.fatal_alert_cause.bus_intg_violation] = 1;
tl_intg_alert_fields[ral.status.status] = otbn_pkg::StatusLocked;
+
+ // Configure the URND EDN connection to be quick. Unlike RND, there's nothing much that can be
+ // going on while we're waiting for a URND seed, so there's no real benefit to modelling the
+ // possibility that it takes ages.
+ m_edn_pull_agent_cfg[UrndEdnIdx].device_delay_min = 0;
+ m_edn_pull_agent_cfg[UrndEdnIdx].device_delay_max = 2;
endfunction
function logic [127:0] get_imem_key();
