lm32_functions.v

Mon, 05 Apr 2010 21:00:31 +0100

author
Philip Pemberton <philpem@philpem.me.uk>
date
Mon, 05 Apr 2010 21:00:31 +0100
changeset 6
a8e459b24c31
parent 0
cd0b58aa6f83
child 26
73de224304c1
permissions
-rw-r--r--

reduce size of caches to fit in DE1 FPGA

The default cache size makes the Icache and Dcache "just a bit" too big to
fit in the EP2C20 FPGA on the DE1 board. This commit reduces the Icache and
Dcache sizes to the defaults shown in the LatticeMico32 Processor Reference
Manual (pages 36 and 37).

     1 // =============================================================================
     2 //                           COPYRIGHT NOTICE
     3 // Copyright 2006 (c) Lattice Semiconductor Corporation
     4 // ALL RIGHTS RESERVED
     5 // This confidential and proprietary software may be used only as authorised by
     6 // a licensing agreement from Lattice Semiconductor Corporation.
     7 // The entire notice above must be reproduced on all authorized copies and
     8 // copies may only be made to the extent permitted by a licensing agreement from
     9 // Lattice Semiconductor Corporation.
    10 //
    11 // Lattice Semiconductor Corporation        TEL : 1-800-Lattice (USA and Canada)
    12 // 5555 NE Moore Court                            408-826-6000 (other locations)
    13 // Hillsboro, OR 97124                     web  : http://www.latticesemi.com/
    14 // U.S.A                                   email: techsupport@latticesemi.com
    15 // =============================================================================/
    16 //                         FILE DETAILS
    17 // Project      : LatticeMico32
    18 // File         : lm32_functions.v
    19 // Title        : Common functions
    20 // Version      : 6.1.17
    21 //              : Initial Release
    22 // Version      : 7.0SP2, 3.0
    23 //              : No Change
    24 // Version      : 3.5
    25 //              : Added function to generate log-of-two that rounds-up to
    26 //              : power-of-two
    27 // =============================================================================
    29 function integer clogb2;
    30 input [31:0] value;
    31 begin
    32    for (clogb2 = 0; value > 0; clogb2 = clogb2 + 1)
    33         value = value >> 1;
    34 end
    35 endfunction 
    37 function integer clogb2_v1;
    38 input [31:0] value;
    39 reg   [31:0] i;
    40 reg   [31:0] temp;
    41 begin
    42    temp = 0;
    43    i    = 0;
    44    for (i = 0; temp < value; i = i + 1)  
    45 	temp = 1<<i;
    46    clogb2_v1 = i-1;
    47 end
    48 endfunction