[BUG] "Virtual" test list fails when icache settings are modified

[LQUA]

Is there an existing CVA6 bug for this?

• I have searched the existing bug issues

Bug Description

This issue can be encountered in most tests in the testlist_riscv-tests-XXXX-v test list, let's focus on the first one : rv64ui-v-add, with the target cv64a6_imafdc_sv39 (as an "all inclusive" target).

The original Icache settings for the target are :

  localparam CVA6ConfigIcacheByteSize = 16384;
  localparam CVA6ConfigIcacheSetAssoc = 4;

If we change these settings to something else, for instance

  localparam CVA6ConfigIcacheByteSize = 2048;
  localparam CVA6ConfigIcacheSetAssoc = 2;

the test rv64ui-v-add is failed.

The failure comes from the trap adress read in stval which differs from 0x2002 (SPIKE) to 0x2004 (SIMU)

After some research, I think that the issue might be related to the exception data path. In the file frontend.sv and its involved subentities, icache_dreq_i.ex.tval is somehow 'forgotten' to be replaced by icache_dreq_i.vaddr to form the new tval.
But, icache_dreq_i.vaddr depends on the icache activity and also on its topology (cache size, associativity). I have the feeling that the right trapping adress that should be used for tval is in icache_dreq_i.ex.tval, and that the following icache_dreq_i.vaddr continues to run during the exception handling, not reflecting the adress that caused the exception anymore.