[config] Add an Opentitan configuration

This adds the configuration instantiated in Opentitan and adds
missing prim support to allow the TB to run that configuration.

Resolves lowRISC#1362

Signed-off-by: Tom Roberts <[email protected]>

Author: Tom Roberts

azure-pipelines.yml

@@ -97,7 +97,7 @@ jobs:
         - small
         - experimental-maxperf-pmp
         - experimental-maxperf-pmp-bmfull
-        - experimental-maxperf-pmp-bmfull-icache
+        - opentitan
         - experimental-branch-predictor
 
   # Run lint on simple system

dv/riscv_compliance/ibex_riscv_compliance.core

@@ -96,6 +96,12 @@ parameters:
     paramtype: vlogparam
     description: "Number of PMP regions"
 
+  SecureIbex:
+    datatype: int
+    paramtype: vlogparam
+    default: 0
+    description: "Enables security hardening features (EXPERIMENTAL) [0/1]"
+
 targets:
   sim:
     default_tool: verilator
@@ -115,6 +121,7 @@ targets:
       - PMPEnable
       - PMPGranularity
       - PMPNumRegions
+      - SecureIbex
     toplevel: ibex_riscv_compliance
     tools:
       verilator:

dv/riscv_compliance/rtl/ibex_riscv_compliance.sv

@@ -27,6 +27,7 @@ module ibex_riscv_compliance (
   parameter bit ICache                  = 1'b0;
   parameter bit ICacheECC               = 1'b0;
   parameter bit BranchPredictor         = 1'b0;
+  parameter bit SecureIbex              = 1'b0;
 
   logic clk_sys, rst_sys_n;
 
@@ -125,6 +126,7 @@ module ibex_riscv_compliance (
       .ICache          (ICache          ),
       .ICacheECC       (ICacheECC       ),
       .BranchPredictor (BranchPredictor ),
+      .SecureIbex      (SecureIbex      ),
       .DmHaltAddr      (32'h00000000    ),
       .DmExceptionAddr (32'h00000000    )
     ) u_top (

dv/uvm/core_ibex/Makefile

@@ -65,7 +65,7 @@ PMP_REGIONS         := 16
 # PMP Granularity
 PMP_GRANULARITY     := 0
 
-IBEX_CONFIG         := experimental-maxperf-pmp-bmfull-icache
+IBEX_CONFIG         := opentitan
 
 # TODO(udinator) - might need options for SAIL/Whisper/Spike
 ifeq (${ISS},ovpsim)

dv/uvm/core_ibex/common/prim/prim_buf.sv

@@ -0,0 +1,22 @@
+// Copyright lowRISC contributors.
+// Licensed under the Apache License, Version 2.0, see LICENSE for details.
+// SPDX-License-Identifier: Apache-2.0
+
+// Abstract primitives wrapper.
+//
+// This file is a stop-gap until the DV file list is generated by FuseSoC.
+// Its contents are taken from the file which would be generated by FuseSoC.
+// https://github.com/lowRISC/ibex/issues/893
+
+module prim_buf (
+  input in_i,
+  output logic out_o
+);
+
+  if (1) begin : gen_generic
+    prim_generic_buf u_impl_generic (
+      .*
+    );
+  end
+
+endmodule

dv/uvm/core_ibex/ibex_dv.f

@@ -33,6 +33,8 @@
 ${PRJ_DIR}/dv/uvm/core_ibex/common/prim/prim_ram_1p.sv
 ${PRJ_DIR}/vendor/lowrisc_ip/ip/prim_generic/rtl/prim_generic_clock_gating.sv
 ${PRJ_DIR}/dv/uvm/core_ibex/common/prim/prim_clock_gating.sv
+${PRJ_DIR}/vendor/lowrisc_ip/ip/prim_generic/rtl/prim_generic_buf.sv
+${PRJ_DIR}/dv/uvm/core_ibex/common/prim/prim_buf.sv
 
 // ibex CORE RTL files
 +incdir+${PRJ_DIR}/rtl

dv/uvm/core_ibex/tb/core_ibex_tb_top.sv

@@ -57,6 +57,7 @@ module core_ibex_tb_top;
   parameter bit ICache                   = 1'b0;
   parameter bit ICacheECC                = 1'b0;
   parameter bit BranchPredictor          = 1'b0;
+  parameter bit SecureIbex               = 1'b0;
 
   ibex_top_tracing #(
     .DmHaltAddr      (32'h`BOOT_ADDR + 'h0 ),
@@ -72,6 +73,7 @@ module core_ibex_tb_top;
     .WritebackStage  (WritebackStage   ),
     .ICache          (ICache           ),
     .ICacheECC       (ICacheECC        ),
+    .SecureIbex      (SecureIbex       ),
     .BranchPredictor (BranchPredictor  )
   ) dut (
     .clk_i          (clk                  ),

ibex_configs.yaml

@@ -20,6 +20,23 @@ small:
   PMPEnable                : 0
   PMPGranularity           : 0
   PMPNumRegions            : 4
+  SecureIbex               : 0
+
+# Configuration to match that used in the OpenTitan project
+opentitan:
+  RV32E                    : 0
+  RV32M                    : "ibex_pkg::RV32MSingleCycle"
+  RV32B                    : "ibex_pkg::RV32BNone"
+  RegFile                  : "ibex_pkg::RegFileFF"
+  BranchTargetALU          : 1
+  WritebackStage           : 1
+  ICache                   : 1
+  ICacheECC                : 1
+  BranchPredictor          : 0
+  PMPEnable                : 1
+  PMPGranularity           : 0
+  PMPNumRegions            : 16
+  SecureIbex               : 1
 
 # ===============================
 # * EXPERIMENTAL CONFIGURATIONS *
@@ -41,6 +58,7 @@ experimental-maxperf:
   PMPEnable                : 0
   PMPGranularity           : 0
   PMPNumRegions            : 4
+  SecureIbex               : 0
 
 # experimental-maxperf config above plus PMP enabled with 16 regions.
 experimental-maxperf-pmp:
@@ -56,6 +74,7 @@ experimental-maxperf-pmp:
   PMPEnable                : 1
   PMPGranularity           : 0
   PMPNumRegions            : 16
+  SecureIbex               : 0
 
 # experimental-maxperf-pmp config above with balanced bitmanip extension
 experimental-maxperf-pmp-bmbalanced:
@@ -71,6 +90,7 @@ experimental-maxperf-pmp-bmbalanced:
   PMPEnable                : 1
   PMPGranularity           : 0
   PMPNumRegions            : 16
+  SecureIbex               : 0
 
 # experimental-maxperf-pmp config above with full bitmanip extension
 experimental-maxperf-pmp-bmfull:
@@ -86,6 +106,7 @@ experimental-maxperf-pmp-bmfull:
   PMPEnable                : 1
   PMPGranularity           : 0
   PMPNumRegions            : 16
+  SecureIbex               : 0
 
 # experimental-maxperf-pmp-bmfull config above with icache enabled
 experimental-maxperf-pmp-bmfull-icache:
@@ -101,6 +122,7 @@ experimental-maxperf-pmp-bmfull-icache:
   PMPEnable                : 1
   PMPGranularity           : 0
   PMPNumRegions            : 16
+  SecureIbex               : 0
 
 # experimental-maxperf with branch predictor switched on. This exists to allow
 # easy use of Ibex with the branch predictor in particular for CI runs. The
@@ -119,4 +141,5 @@ experimental-branch-predictor:
   PMPEnable                : 0
   PMPGranularity           : 0
   PMPNumRegions            : 4
+  SecureIbex               : 0