Introduce avoid_neg() guard function for array sizing

openhwgroup · Dec 20, 2024 · 9104f41 · 9104f41
1 parent 40ba10c
commit 9104f41
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Showing 10 changed files with 29 additions and 19 deletions.
diff --git a/core/acc_dispatcher.sv b/core/acc_dispatcher.sv
@@ -41,8 +41,8 @@ module acc_dispatcher
     // Interface with the CSRs
     input priv_lvl_t ld_st_priv_lvl_i,
     input logic sum_i,
-    input pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0] pmpcfg_i,
-    input logic [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
+    input pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0] pmpcfg_i,
+    input logic [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
     input logic [2:0] fcsr_frm_i,
     output logic dirty_v_state_o,
     input logic acc_mmu_en_i,

diff --git a/core/csr_regfile.sv b/core/csr_regfile.sv
@@ -161,9 +161,9 @@ module csr_regfile
     // TO_BE_COMPLETED - PERF_COUNTERS
     output logic perf_we_o,
     // PMP configuration containing pmpcfg for max 64 PMPs - ACC_DISPATCHER
-    output riscv::pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0] pmpcfg_o,
+    output riscv::pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0] pmpcfg_o,
     // PMP addresses - ACC_DISPATCHER
-    output logic [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr_o,
+    output logic [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr_o,
     // TO_BE_COMPLETED - PERF_COUNTERS
     output logic [31:0] mcountinhibit_o,
     // RVFI

diff --git a/core/cva6.sv b/core/cva6.sv
@@ -573,8 +573,8 @@ module cva6
   logic acc_cons_en_csr;
   logic debug_mode;
   logic single_step_csr_commit;
-  riscv::pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0] pmpcfg;
-  logic [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr;
+  riscv::pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0] pmpcfg;
+  logic [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr;
   logic [31:0] mcountinhibit_csr_perf;
   // ----------------------------
   // Performance Counters <-> *

diff --git a/core/cva6_mmu/cva6_mmu.sv b/core/cva6_mmu/cva6_mmu.sv
@@ -100,8 +100,8 @@ module cva6_mmu
 
     // PMP
 
-    input riscv::pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0]                   pmpcfg_i,
-    input logic           [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr_i
+    input riscv::pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0]                   pmpcfg_i,
+    input logic           [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr_i
 );
 
   // memory management, pte for cva6

diff --git a/core/cva6_mmu/cva6_ptw.sv b/core/cva6_mmu/cva6_ptw.sv
@@ -83,8 +83,8 @@ module cva6_ptw
     output logic shared_tlb_miss_o,
 
     // PMP
-    input riscv::pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0] pmpcfg_i,
-    input logic [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
+    input riscv::pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0] pmpcfg_i,
+    input logic [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
     output logic [CVA6Cfg.PLEN-1:0] bad_paddr_o,
     output logic [CVA6Cfg.GPLEN-1:0] bad_gpaddr_o
 );

diff --git a/core/ex_stage.sv b/core/ex_stage.sv
@@ -227,9 +227,9 @@ module ex_stage
     // To count the data TLB misses - PERF_COUNTERS
     output logic dtlb_miss_o,
     // Report the PMP configuration - CSR_REGFILE
-    input riscv::pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0] pmpcfg_i,
+    input riscv::pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0] pmpcfg_i,
     // Report the PMP addresses - CSR_REGFILE
-    input logic [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
+    input logic [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
     // Information dedicated to RVFI - RVFI
     output lsu_ctrl_t rvfi_lsu_ctrl_o,
     // Information dedicated to RVFI - RVFI

diff --git a/core/include/ariane_pkg.sv b/core/include/ariane_pkg.sv
@@ -800,4 +800,12 @@ package ariane_pkg;
     return gppn;
   endfunction : make_gppn
 
+  // ----------------------
+  // Helper functions
+  // ----------------------
+  // Avoid negative array slices when defining parametrized sizes
+  function automatic int unsigned avoid_neg(int n);
+    return (n < 0) ? 0 : n;
+  endfunction : avoid_neg
+
 endpackage
diff --git a/core/load_store_unit.sv b/core/load_store_unit.sv
@@ -154,9 +154,9 @@ module load_store_unit
     input  amo_resp_t           amo_resp_i,
 
     // PMP configuration - CSR_REGFILE
-    input riscv::pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0]                   pmpcfg_i,
+    input riscv::pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0]                   pmpcfg_i,
     // PMP address - CSR_REGFILE
-    input logic           [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
+    input logic           [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr_i,
 
     // RVFI inforamtion - RVFI
     output lsu_ctrl_t                    rvfi_lsu_ctrl_o,

diff --git a/core/pmp/src/pmp.sv b/core/pmp/src/pmp.sv
@@ -12,7 +12,9 @@
 // Date: 2.10.2019
 // Description: purely combinatorial PMP unit (with extraction for more complex configs such as NAPOT)
 
-module pmp #(
+module pmp
+  import ariane_pkg::*;
+#(
     parameter config_pkg::cva6_cfg_t CVA6Cfg    = config_pkg::cva6_cfg_empty,
     parameter int unsigned           PLEN       = 34,                          // rv64: 56
     parameter int unsigned           PMP_LEN    = 32,                          // rv64: 54
@@ -23,8 +25,8 @@ module pmp #(
     input riscv::pmp_access_t access_type_i,
     input riscv::priv_lvl_t priv_lvl_i,
     // Configuration
-    input logic [(NR_ENTRIES > 0 ? NR_ENTRIES-1 : 0):0][PMP_LEN-1:0] conf_addr_i,
-    input riscv::pmpcfg_t [(NR_ENTRIES > 0 ? NR_ENTRIES-1 : 0):0] conf_i,
+    input logic [avoid_neg(NR_ENTRIES-1):0][PMP_LEN-1:0] conf_addr_i,
+    input riscv::pmpcfg_t [avoid_neg(NR_ENTRIES-1):0] conf_i,
     // Output
     output logic allow_o
 );

diff --git a/core/pmp/src/pmp_data_if.sv b/core/pmp/src/pmp_data_if.sv
@@ -36,8 +36,8 @@ module pmp_data_if
     input riscv::priv_lvl_t ld_st_priv_lvl_i,
     input logic ld_st_v_i,
     // PMP
-    input riscv::pmpcfg_t [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0] pmpcfg_i,
-    input logic [(CVA6Cfg.NrPMPEntries > 0 ? CVA6Cfg.NrPMPEntries-1 : 0):0][CVA6Cfg.PLEN-3:0] pmpaddr_i
+    input riscv::pmpcfg_t [avoid_neg(CVA6Cfg.NrPMPEntries-1):0] pmpcfg_i,
+    input logic [avoid_neg(CVA6Cfg.NrPMPEntries-1):0][CVA6Cfg.PLEN-3:0] pmpaddr_i
 );
   // virtual address causing the exception
   logic [CVA6Cfg.XLEN-1:0] fetch_vaddr_xlen, lsu_vaddr_xlen;