lm32_instruction_unit.v

changeset 26
73de224304c1
parent 8
07be9df9fee8
child 27
d6c693415d59
     1.1 diff -r 35dc7ba83714 -r 73de224304c1 lm32_instruction_unit.v
     1.2 --- a/lm32_instruction_unit.v	Sun Mar 06 21:14:43 2011 +0000
     1.3 +++ b/lm32_instruction_unit.v	Sat Aug 06 00:02:46 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 @@ -542,52 +581,63 @@
   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 -            pc_f <= pc_a;
   1.141 -        if (stall_d == `FALSE)
   1.142 -            pc_d <= pc_f;
   1.143 -        if (stall_x == `FALSE)
   1.144 -            pc_x <= pc_d;
   1.145 -        if (stall_m == `FALSE)
   1.146 -            pc_m <= pc_x;
   1.147 -        pc_w <= pc_m;
   1.148 -    end
   1.149 -end
   1.150 +  begin
   1.151 +     if (rst_i == `TRUE)
   1.152 +       begin
   1.153 +`ifdef CFG_DEBUG_ENABLED
   1.154 + `ifdef CFG_ALTERNATE_EBA
   1.155 +	  if (at_debug == `TRUE)
   1.156 +	    pc_f <= #1 (`CFG_DEBA_RESET-4)/4;
   1.157 +	  else
   1.158 +	    pc_f <= #1 (`CFG_EBA_RESET-4)/4;
   1.159 + `else
   1.160 +	  pc_f <= #1 (`CFG_EBA_RESET-4)/4;
   1.161 + `endif
   1.162 +`else
   1.163 +          pc_f <= #1 (`CFG_EBA_RESET-4)/4;
   1.164 +`endif
   1.165 +          pc_d <= #1 {`LM32_PC_WIDTH{1'b0}};
   1.166 +          pc_x <= #1 {`LM32_PC_WIDTH{1'b0}};
   1.167 +          pc_m <= #1 {`LM32_PC_WIDTH{1'b0}};
   1.168 +          pc_w <= #1 {`LM32_PC_WIDTH{1'b0}};
   1.169 +       end
   1.170 +     else
   1.171 +       begin
   1.172 +          if (stall_f == `FALSE)
   1.173 +            pc_f <= #1 pc_a;
   1.174 +          if (stall_d == `FALSE)
   1.175 +            pc_d <= #1 pc_f;
   1.176 +          if (stall_x == `FALSE)
   1.177 +            pc_x <= #1 pc_d;
   1.178 +          if (stall_m == `FALSE)
   1.179 +            pc_m <= #1 pc_x;
   1.180 +          pc_w <= #1 pc_m;
   1.181 +       end
   1.182 +  end
   1.183  
   1.184  `ifdef LM32_CACHE_ENABLED
   1.185  // Address to restart from after a cache miss has been handled
   1.186  always @(posedge clk_i `CFG_RESET_SENSITIVITY)
   1.187  begin
   1.188      if (rst_i == `TRUE)
   1.189 -        restart_address <= {`LM32_PC_WIDTH{1'b0}};
   1.190 +        restart_address <= #1 {`LM32_PC_WIDTH{1'b0}};
   1.191      else
   1.192      begin
   1.193  `ifdef CFG_DCACHE_ENABLED
   1.194  `ifdef CFG_ICACHE_ENABLED        
   1.195              // D-cache restart address must take priority, otherwise instructions will be lost
   1.196              if (dcache_refill_request == `TRUE)
   1.197 -                restart_address <= pc_w;
   1.198 +                restart_address <= #1 pc_w;
   1.199              else if ((icache_refill_request == `TRUE) && (!dcache_refilling) && (!dcache_restart_request))
   1.200 -                restart_address <= icache_refill_address;
   1.201 +                restart_address <= #1 icache_refill_address;
   1.202  `else
   1.203              if (dcache_refill_request == `TRUE)
   1.204 -                restart_address <= pc_w;
   1.205 +                restart_address <= #1 pc_w;
   1.206  `endif
   1.207  `else
   1.208  `ifdef CFG_ICACHE_ENABLED        
   1.209              if (icache_refill_request == `TRUE)
   1.210 -                restart_address <= icache_refill_address;
   1.211 +                restart_address <= #1 icache_refill_address;
   1.212  `endif
   1.213  `endif
   1.214      end
   1.215 @@ -599,11 +649,11 @@
   1.216  always @(posedge clk_i `CFG_RESET_SENSITIVITY)
   1.217  begin
   1.218      if (rst_i == `TRUE)
   1.219 -        irom_select_f <= `FALSE;
   1.220 +        irom_select_f <= #1 `FALSE;
   1.221      else
   1.222      begin
   1.223          if (stall_f == `FALSE)
   1.224 -            irom_select_f <= irom_select_a;
   1.225 +            irom_select_f <= #1 irom_select_a;
   1.226      end
   1.227  end
   1.228  `endif
   1.229 @@ -628,25 +678,25 @@
   1.230  begin
   1.231      if (rst_i == `TRUE)
   1.232      begin
   1.233 -        i_cyc_o <= `FALSE;
   1.234 -        i_stb_o <= `FALSE;
   1.235 -        i_adr_o <= {`LM32_WORD_WIDTH{1'b0}};
   1.236 -        i_cti_o <= `LM32_CTYPE_END;
   1.237 -        i_lock_o <= `FALSE;
   1.238 -        icache_refill_data <= {`LM32_INSTRUCTION_WIDTH{1'b0}};
   1.239 -        icache_refill_ready <= `FALSE;
   1.240 +        i_cyc_o <= #1 `FALSE;
   1.241 +        i_stb_o <= #1 `FALSE;
   1.242 +        i_adr_o <= #1 {`LM32_WORD_WIDTH{1'b0}};
   1.243 +        i_cti_o <= #1 `LM32_CTYPE_END;
   1.244 +        i_lock_o <= #1 `FALSE;
   1.245 +        icache_refill_data <= #1 {`LM32_INSTRUCTION_WIDTH{1'b0}};
   1.246 +        icache_refill_ready <= #1 `FALSE;
   1.247  `ifdef CFG_BUS_ERRORS_ENABLED
   1.248 -        bus_error_f <= `FALSE;
   1.249 +        bus_error_f <= #1 `FALSE;
   1.250  `endif
   1.251  `ifdef CFG_HW_DEBUG_ENABLED
   1.252 -        i_we_o <= `FALSE;
   1.253 -        i_sel_o <= 4'b1111;
   1.254 -        jtag_access <= `FALSE;
   1.255 +        i_we_o <= #1 `FALSE;
   1.256 +        i_sel_o <= #1 4'b1111;
   1.257 +        jtag_access <= #1 `FALSE;
   1.258  `endif
   1.259      end
   1.260      else
   1.261      begin   
   1.262 -        icache_refill_ready <= `FALSE;
   1.263 +        icache_refill_ready <= #1 `FALSE;
   1.264          // Is a cycle in progress?
   1.265          if (i_cyc_o == `TRUE)
   1.266          begin
   1.267 @@ -656,10 +706,10 @@
   1.268  `ifdef CFG_HW_DEBUG_ENABLED
   1.269                  if (jtag_access == `TRUE)
   1.270                  begin
   1.271 -                    i_cyc_o <= `FALSE;
   1.272 -                    i_stb_o <= `FALSE;       
   1.273 -                    i_we_o <= `FALSE;  
   1.274 -                    jtag_access <= `FALSE;    
   1.275 +                    i_cyc_o <= #1 `FALSE;
   1.276 +                    i_stb_o <= #1 `FALSE;       
   1.277 +                    i_we_o <= #1 `FALSE;  
   1.278 +                    jtag_access <= #1 `FALSE;    
   1.279                  end
   1.280                  else
   1.281  `endif
   1.282 @@ -667,22 +717,22 @@
   1.283                      if (last_word == `TRUE)
   1.284                      begin
   1.285                          // Cache line fill complete 
   1.286 -                        i_cyc_o <= `FALSE;
   1.287 -                        i_stb_o <= `FALSE;
   1.288 -                        i_lock_o <= `FALSE;
   1.289 +                        i_cyc_o <= #1 `FALSE;
   1.290 +                        i_stb_o <= #1 `FALSE;
   1.291 +                        i_lock_o <= #1 `FALSE;
   1.292                      end
   1.293                      // Fetch next word in cache line
   1.294 -                    i_adr_o[addr_offset_msb:addr_offset_lsb] <= i_adr_o[addr_offset_msb:addr_offset_lsb] + 1'b1;
   1.295 -                    i_cti_o <= next_cycle_type;
   1.296 +                    i_adr_o[addr_offset_msb:addr_offset_lsb] <= #1 i_adr_o[addr_offset_msb:addr_offset_lsb] + 1'b1;
   1.297 +                    i_cti_o <= #1 next_cycle_type;
   1.298                      // Write fetched data into instruction cache
   1.299 -                    icache_refill_ready <= `TRUE;
   1.300 -                    icache_refill_data <= i_dat_i;
   1.301 +                    icache_refill_ready <= #1 `TRUE;
   1.302 +                    icache_refill_data <= #1 i_dat_i;
   1.303                  end
   1.304              end
   1.305  `ifdef CFG_BUS_ERRORS_ENABLED
   1.306              if (i_err_i == `TRUE)
   1.307              begin
   1.308 -                bus_error_f <= `TRUE;
   1.309 +                bus_error_f <= #1 `TRUE;
   1.310                  $display ("Instruction bus error. Address: %x", i_adr_o);
   1.311              end
   1.312  `endif
   1.313 @@ -693,15 +743,15 @@
   1.314              begin
   1.315                  // Read first word of cache line
   1.316  `ifdef CFG_HW_DEBUG_ENABLED     
   1.317 -                i_sel_o <= 4'b1111;
   1.318 +                i_sel_o <= #1 4'b1111;
   1.319  `endif
   1.320 -                i_adr_o <= {first_address, 2'b00};
   1.321 -                i_cyc_o <= `TRUE;
   1.322 -                i_stb_o <= `TRUE;                
   1.323 -                i_cti_o <= first_cycle_type;
   1.324 -                //i_lock_o <= `TRUE;
   1.325 +                i_adr_o <= #1 {first_address, 2'b00};
   1.326 +                i_cyc_o <= #1 `TRUE;
   1.327 +                i_stb_o <= #1 `TRUE;                
   1.328 +                i_cti_o <= #1 first_cycle_type;
   1.329 +                //i_lock_o <= #1 `TRUE;
   1.330  `ifdef CFG_BUS_ERRORS_ENABLED
   1.331 -                bus_error_f <= `FALSE;
   1.332 +                bus_error_f <= #1 `FALSE;
   1.333  `endif
   1.334              end
   1.335  `ifdef CFG_HW_DEBUG_ENABLED
   1.336 @@ -710,18 +760,18 @@
   1.337                  if ((jtag_read_enable == `TRUE) || (jtag_write_enable == `TRUE))
   1.338                  begin
   1.339                      case (jtag_address[1:0])
   1.340 -                    2'b00: i_sel_o <= 4'b1000;
   1.341 -                    2'b01: i_sel_o <= 4'b0100;
   1.342 -                    2'b10: i_sel_o <= 4'b0010;
   1.343 -                    2'b11: i_sel_o <= 4'b0001;
   1.344 +                    2'b00: i_sel_o <= #1 4'b1000;
   1.345 +                    2'b01: i_sel_o <= #1 4'b0100;
   1.346 +                    2'b10: i_sel_o <= #1 4'b0010;
   1.347 +                    2'b11: i_sel_o <= #1 4'b0001;
   1.348                      endcase
   1.349 -                    i_adr_o <= jtag_address;
   1.350 -                    i_dat_o <= {4{jtag_write_data}};
   1.351 -                    i_cyc_o <= `TRUE;
   1.352 -                    i_stb_o <= `TRUE;
   1.353 -                    i_we_o <= jtag_write_enable;
   1.354 -                    i_cti_o <= `LM32_CTYPE_END;
   1.355 -                    jtag_access <= `TRUE;
   1.356 +                    i_adr_o <= #1 jtag_address;
   1.357 +                    i_dat_o <= #1 {4{jtag_write_data}};
   1.358 +                    i_cyc_o <= #1 `TRUE;
   1.359 +                    i_stb_o <= #1 `TRUE;
   1.360 +                    i_we_o <= #1 jtag_write_enable;
   1.361 +                    i_cti_o <= #1 `LM32_CTYPE_END;
   1.362 +                    jtag_access <= #1 `TRUE;
   1.363                  end
   1.364              end 
   1.365  `endif                    
   1.366 @@ -730,10 +780,10 @@
   1.367              // continually generated if exception handler is cached
   1.368  `ifdef CFG_FAST_UNCONDITIONAL_BRANCH    
   1.369              if (branch_taken_x == `TRUE)
   1.370 -                bus_error_f <= `FALSE;
   1.371 +                bus_error_f <= #1 `FALSE;
   1.372  `endif
   1.373              if (branch_taken_m == `TRUE)
   1.374 -                bus_error_f <= `FALSE;
   1.375 +                bus_error_f <= #1 `FALSE;
   1.376  `endif
   1.377          end
   1.378      end
   1.379 @@ -743,14 +793,14 @@
   1.380  begin
   1.381      if (rst_i == `TRUE)
   1.382      begin
   1.383 -        i_cyc_o <= `FALSE;
   1.384 -        i_stb_o <= `FALSE;
   1.385 -        i_adr_o <= {`LM32_WORD_WIDTH{1'b0}};
   1.386 -        i_cti_o <= `LM32_CTYPE_END;
   1.387 -        i_lock_o <= `FALSE;
   1.388 -        wb_data_f <= {`LM32_INSTRUCTION_WIDTH{1'b0}};
   1.389 +        i_cyc_o <= #1 `FALSE;
   1.390 +        i_stb_o <= #1 `FALSE;
   1.391 +        i_adr_o <= #1 {`LM32_WORD_WIDTH{1'b0}};
   1.392 +        i_cti_o <= #1 `LM32_CTYPE_END;
   1.393 +        i_lock_o <= #1 `FALSE;
   1.394 +        wb_data_f <= #1 {`LM32_INSTRUCTION_WIDTH{1'b0}};
   1.395  `ifdef CFG_BUS_ERRORS_ENABLED
   1.396 -        bus_error_f <= `FALSE;
   1.397 +        bus_error_f <= #1 `FALSE;
   1.398  `endif
   1.399      end
   1.400      else
   1.401 @@ -762,15 +812,15 @@
   1.402              if((i_ack_i == `TRUE) || (i_err_i == `TRUE))
   1.403              begin
   1.404                  // Cycle complete
   1.405 -                i_cyc_o <= `FALSE;
   1.406 -                i_stb_o <= `FALSE;
   1.407 +                i_cyc_o <= #1 `FALSE;
   1.408 +                i_stb_o <= #1 `FALSE;
   1.409                  // Register fetched instruction
   1.410 -                wb_data_f <= i_dat_i;
   1.411 +                wb_data_f <= #1 i_dat_i;
   1.412              end
   1.413  `ifdef CFG_BUS_ERRORS_ENABLED
   1.414              if (i_err_i == `TRUE)
   1.415              begin
   1.416 -                bus_error_f <= `TRUE;
   1.417 +                bus_error_f <= #1 `TRUE;
   1.418                  $display ("Instruction bus error. Address: %x", i_adr_o);
   1.419              end
   1.420  `endif
   1.421 @@ -786,13 +836,13 @@
   1.422              begin
   1.423                  // Fetch instruction
   1.424  `ifdef CFG_HW_DEBUG_ENABLED     
   1.425 -                i_sel_o <= 4'b1111;
   1.426 +                i_sel_o <= #1 4'b1111;
   1.427  `endif
   1.428 -                i_adr_o <= {pc_a, 2'b00};
   1.429 -                i_cyc_o <= `TRUE;
   1.430 -                i_stb_o <= `TRUE;
   1.431 +                i_adr_o <= #1 {pc_a, 2'b00};
   1.432 +                i_cyc_o <= #1 `TRUE;
   1.433 +                i_stb_o <= #1 `TRUE;
   1.434  `ifdef CFG_BUS_ERRORS_ENABLED
   1.435 -                bus_error_f <= `FALSE;
   1.436 +                bus_error_f <= #1 `FALSE;
   1.437  `endif
   1.438              end
   1.439  	    else
   1.440 @@ -804,7 +854,7 @@
   1.441  	           )
   1.442  		begin
   1.443  `ifdef CFG_BUS_ERRORS_ENABLED
   1.444 -		    bus_error_f <= `FALSE;
   1.445 +		    bus_error_f <= #1 `FALSE;
   1.446  `endif
   1.447  		end
   1.448  	    end
   1.449 @@ -819,18 +869,18 @@
   1.450  begin
   1.451      if (rst_i == `TRUE)
   1.452      begin
   1.453 -        instruction_d <= {`LM32_INSTRUCTION_WIDTH{1'b0}};
   1.454 +        instruction_d <= #1 {`LM32_INSTRUCTION_WIDTH{1'b0}};
   1.455  `ifdef CFG_BUS_ERRORS_ENABLED
   1.456 -        bus_error_d <= `FALSE;
   1.457 +        bus_error_d <= #1 `FALSE;
   1.458  `endif
   1.459      end
   1.460      else
   1.461      begin
   1.462          if (stall_d == `FALSE)
   1.463          begin
   1.464 -            instruction_d <= instruction_f;
   1.465 +            instruction_d <= #1 instruction_f;
   1.466  `ifdef CFG_BUS_ERRORS_ENABLED
   1.467 -            bus_error_d <= bus_error_f;
   1.468 +            bus_error_d <= #1 bus_error_f;
   1.469  `endif
   1.470          end
   1.471      end