rtl/lm32_instruction_unit.v

changeset 28
da23ab8ef7b4
parent 27
d6c693415d59
parent 24
c336e674a37e
     1.1 diff -r 7422134cbfea -r da23ab8ef7b4 rtl/lm32_instruction_unit.v
     1.2 --- a/rtl/lm32_instruction_unit.v	Tue Mar 08 09:59:34 2011 +0000
     1.3 +++ b/rtl/lm32_instruction_unit.v	Sat Aug 06 01:32:07 2011 +0100
     1.4 @@ -1,18 +1,39 @@
     1.5 -// =============================================================================
     1.6 -//                           COPYRIGHT NOTICE
     1.7 -// Copyright 2006 (c) Lattice Semiconductor Corporation
     1.8 -// ALL RIGHTS RESERVED
     1.9 -// This confidential and proprietary software may be used only as authorised by
    1.10 -// a licensing agreement from Lattice Semiconductor Corporation.
    1.11 -// The entire notice above must be reproduced on all authorized copies and
    1.12 -// copies may only be made to the extent permitted by a licensing agreement from
    1.13 -// Lattice Semiconductor Corporation.
    1.14 +//   ==================================================================
    1.15 +//   >>>>>>>>>>>>>>>>>>>>>>> COPYRIGHT NOTICE <<<<<<<<<<<<<<<<<<<<<<<<<
    1.16 +//   ------------------------------------------------------------------
    1.17 +//   Copyright (c) 2006-2011 by Lattice Semiconductor Corporation
    1.18 +//   ALL RIGHTS RESERVED 
    1.19 +//   ------------------------------------------------------------------
    1.20 +//
    1.21 +//   IMPORTANT: THIS FILE IS AUTO-GENERATED BY THE LATTICEMICO SYSTEM.
    1.22 +//
    1.23 +//   Permission:
    1.24 +//
    1.25 +//      Lattice Semiconductor grants permission to use this code
    1.26 +//      pursuant to the terms of the Lattice Semiconductor Corporation
    1.27 +//      Open Source License Agreement.  
    1.28 +//
    1.29 +//   Disclaimer:
    1.30  //
    1.31 -// Lattice Semiconductor Corporation        TEL : 1-800-Lattice (USA and Canada)
    1.32 -// 5555 NE Moore Court                            408-826-6000 (other locations)
    1.33 -// Hillsboro, OR 97124                     web  : http://www.latticesemi.com/
    1.34 -// U.S.A                                   email: techsupport@latticesemi.com
    1.35 -// =============================================================================/
    1.36 +//      Lattice Semiconductor provides no warranty regarding the use or
    1.37 +//      functionality of this code. It is the user's responsibility to
    1.38 +//      verify the user’s design for consistency and functionality through
    1.39 +//      the use of formal verification methods.
    1.40 +//
    1.41 +//   --------------------------------------------------------------------
    1.42 +//
    1.43 +//                  Lattice Semiconductor Corporation
    1.44 +//                  5555 NE Moore Court
    1.45 +//                  Hillsboro, OR 97214
    1.46 +//                  U.S.A
    1.47 +//
    1.48 +//                  TEL: 1-800-Lattice (USA and Canada)
    1.49 +//                         503-286-8001 (other locations)
    1.50 +//
    1.51 +//                  web: http://www.latticesemi.com/
    1.52 +//                  email: techsupport@latticesemi.com
    1.53 +//
    1.54 +//   --------------------------------------------------------------------
    1.55  //                         FILE DETAILS
    1.56  // Project      : LatticeMico32
    1.57  // File         : lm32_instruction_unit.v
    1.58 @@ -42,6 +63,9 @@
    1.59  //              : instruction cache) to lock up in to an infinite loop due to a 
    1.60  //              : instruction bus error when EBA was set to instruction inline
    1.61  //              : memory.
    1.62 +// Version      : 3.8 
    1.63 +//              : Feature: Support for dynamically switching EBA to DEBA via a 
    1.64 +//              : GPIO.
    1.65  // =============================================================================
    1.66  
    1.67  `include "lm32_include.v"
    1.68 @@ -54,6 +78,11 @@
    1.69      // ----- Inputs -------
    1.70      clk_i,
    1.71      rst_i,
    1.72 +`ifdef CFG_DEBUG_ENABLED
    1.73 + `ifdef CFG_ALTERNATE_EBA
    1.74 +    at_debug,
    1.75 + `endif
    1.76 +`endif
    1.77      // From pipeline
    1.78      stall_a,
    1.79      stall_f,
    1.80 @@ -161,6 +190,12 @@
    1.81  input clk_i;                                            // Clock
    1.82  input rst_i;                                            // Reset
    1.83  
    1.84 +`ifdef CFG_DEBUG_ENABLED
    1.85 + `ifdef CFG_ALTERNATE_EBA
    1.86 +   input at_debug;                                      // GPIO input that maps EBA to DEBA
    1.87 + `endif
    1.88 +`endif
    1.89 +
    1.90  input stall_a;                                          // Stall A stage instruction
    1.91  input stall_f;                                          // Stall F stage instruction
    1.92  input stall_d;                                          // Stall D stage instruction
    1.93 @@ -334,6 +369,10 @@
    1.94  reg jtag_access;                                        // Indicates if a JTAG WB access is in progress
    1.95  `endif
    1.96  
    1.97 +`ifdef CFG_ALTERNATE_EBA
    1.98 +	reg alternate_eba_taken;
    1.99 +`endif
   1.100 +
   1.101  /////////////////////////////////////////////////////
   1.102  // Functions
   1.103  /////////////////////////////////////////////////////
   1.104 @@ -381,8 +420,8 @@
   1.105  	    .ResetB                 (rst_i),
   1.106  	    .DataInA                ({32{1'b0}}),
   1.107  	    .DataInB                (irom_store_data_m),
   1.108 -	    .AddressA               (pc_a[(clogb2(`CFG_IROM_LIMIT/4-`CFG_IROM_BASE_ADDRESS/4+1)-1)+2-1:2]),
   1.109 -	    .AddressB               (irom_address_xm[(clogb2(`CFG_IROM_LIMIT/4-`CFG_IROM_BASE_ADDRESS/4+1)-1)+2-1:2]),
   1.110 +	    .AddressA               (pc_a[clogb2_v1(`CFG_IROM_LIMIT/4-`CFG_IROM_BASE_ADDRESS/4+1)+2-1:2]),
   1.111 +	    .AddressB               (irom_address_xm[clogb2_v1(`CFG_IROM_LIMIT/4-`CFG_IROM_BASE_ADDRESS/4+1)+2-1:2]),
   1.112  	    .ClockEnA               (!stall_a),
   1.113  	    .ClockEnB               (!stall_x || !stall_m),
   1.114  	    .WrA                    (`FALSE),
   1.115 @@ -469,7 +508,7 @@
   1.116              pc_a = restart_address;
   1.117  	  else 
   1.118  `endif        
   1.119 -            pc_a = pc_f + 1'b1;
   1.120 +	    pc_a = pc_f + 1'b1;
   1.121  end
   1.122  
   1.123  // Select where instruction should be fetched from
   1.124 @@ -542,28 +581,39 @@
   1.125  
   1.126  // PC 
   1.127  always @(posedge clk_i `CFG_RESET_SENSITIVITY)
   1.128 -begin
   1.129 -    if (rst_i == `TRUE)
   1.130 -    begin
   1.131 -        pc_f <= (`CFG_EBA_RESET-4)/4;
   1.132 -        pc_d <= {`LM32_PC_WIDTH{1'b0}};
   1.133 -        pc_x <= {`LM32_PC_WIDTH{1'b0}};
   1.134 -        pc_m <= {`LM32_PC_WIDTH{1'b0}};
   1.135 -        pc_w <= {`LM32_PC_WIDTH{1'b0}};
   1.136 -    end
   1.137 -    else
   1.138 -    begin
   1.139 -        if (stall_f == `FALSE)
   1.140 +  begin
   1.141 +     if (rst_i == `TRUE)
   1.142 +       begin
   1.143 +`ifdef CFG_DEBUG_ENABLED
   1.144 + `ifdef CFG_ALTERNATE_EBA
   1.145 +	  if (at_debug == `TRUE)
   1.146 +	    pc_f <= (`CFG_DEBA_RESET-4)/4;
   1.147 +	  else
   1.148 +	    pc_f <= (`CFG_EBA_RESET-4)/4;
   1.149 + `else
   1.150 +	  pc_f <= (`CFG_EBA_RESET-4)/4;
   1.151 + `endif
   1.152 +`else
   1.153 +          pc_f <= (`CFG_EBA_RESET-4)/4;
   1.154 +`endif
   1.155 +          pc_d <= {`LM32_PC_WIDTH{1'b0}};
   1.156 +          pc_x <= {`LM32_PC_WIDTH{1'b0}};
   1.157 +          pc_m <= {`LM32_PC_WIDTH{1'b0}};
   1.158 +          pc_w <= {`LM32_PC_WIDTH{1'b0}};
   1.159 +       end
   1.160 +     else
   1.161 +       begin
   1.162 +          if (stall_f == `FALSE)
   1.163              pc_f <= pc_a;
   1.164 -        if (stall_d == `FALSE)
   1.165 +          if (stall_d == `FALSE)
   1.166              pc_d <= pc_f;
   1.167 -        if (stall_x == `FALSE)
   1.168 +          if (stall_x == `FALSE)
   1.169              pc_x <= pc_d;
   1.170 -        if (stall_m == `FALSE)
   1.171 +          if (stall_m == `FALSE)
   1.172              pc_m <= pc_x;
   1.173 -        pc_w <= pc_m;
   1.174 -    end
   1.175 -end
   1.176 +          pc_w <= pc_m;
   1.177 +       end
   1.178 +  end
   1.179  
   1.180  `ifdef LM32_CACHE_ENABLED
   1.181  // Address to restart from after a cache miss has been handled