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pulp-platform / riscv-dbg

RISC-V Debug Support for our PULP RISC-V Cores
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Question about assertion in dm_top.sv #74

Closed dawidzim closed 3 years ago

dawidzim commented 4 years ago

Hey! I have question about assertion in src/dm_top.sv:

     assert ((DmBaseAddress > 0 && hartinfo_i[i].nscratch >= 2) || (DmBaseAddress == 0 && hartinfo_i[i].nscratch >= 1))
        else $fatal(1, "If the DM is not located at the zero page each hart needs at lest two scratch registers %d %d",i, hartinfo_i[i].nscratch );

and in testbench riscv_dbg/tb/tb_test_env is:

 dm_top #(
       .NrHarts           ( NrHarts           ),
       .BusWidth          ( 32                ),
       .SelectableHarts   ( SELECTABLE_HARTS  )
    ) i_dm_top (

       .clk_i             ( clk_i             ),
       .rst_ni            ( rst_ni            ),
       .testmode_i        ( 1'b0              ),
       .ndmreset_o        ( ndmreset          ),
       .dmactive_o        (                   ), // active debug session TODO
       .debug_req_o       ( dm_debug_req      ),
       .unavailable_i     ( ~SELECTABLE_HARTS ),
       .hartinfo_i        ( '0                ),

so hartinfo_i is always 0 here, so this assert will call $fatal.

bluewww commented 4 years ago

Setting hartinfo_i to 0 was just me being lazy.

bluewww commented 3 years ago

Fixed in #82