Subversion Repositories theia_gpu

`timescale 1ns / 1ps

`include "aDefinitions.v"

//LUT contains LUT for numbers up to 100 in FIXED point scale 17

module SQUAREROOT_LUT

(

        input  wire[`WIDTH-1:0]                  I,

        output reg [`WIDTH-1:0]          O

);

always @( I )

begin

        case (I)

        32'h0: O = 32'h0;

32'h20000: O = 32'h20000;

32'h40000: O = 32'h2d413;

32'h60000: O = 32'h376cf;

32'h80000: O = 32'h40000;

32'ha0000: O = 32'h478dd;

32'hc0000: O = 32'h4e623;

32'he0000: O = 32'h54a9f;

32'h100000: O = 32'h5a827;

32'h120000: O = 32'h60000;

32'h140000: O = 32'h65316;

32'h160000: O = 32'h6a21c;

32'h180000: O = 32'h6ed9e;

32'h1a0000: O = 32'h7360a;

32'h1c0000: O = 32'h77bba;

32'h1e0000: O = 32'h7bef7;

32'h200000: O = 32'h80000;

32'h220000: O = 32'h83f07;

32'h240000: O = 32'h87c3b;

32'h260000: O = 32'h8b7c1;

32'h280000: O = 32'h8f1bb;

32'h2a0000: O = 32'h92a47;

32'h2c0000: O = 32'h9617e;

32'h2e0000: O = 32'h99777;

32'h300000: O = 32'h9cc47;

32'h320000: O = 32'ha0000;

32'h340000: O = 32'ha32b2;

32'h360000: O = 32'ha646e;

32'h380000: O = 32'ha953f;

32'h3a0000: O = 32'hac534;

32'h3c0000: O = 32'haf456;

32'h3e0000: O = 32'hb22b2;

32'h400000: O = 32'hb504f;

32'h420000: O = 32'hb7d37;

32'h440000: O = 32'hba972;

32'h460000: O = 32'hbd508;

32'h480000: O = 32'hc0000;

32'h4a0000: O = 32'hc2a5f;

32'h4c0000: O = 32'hc542e;

32'h4e0000: O = 32'hc7d70;

32'h500000: O = 32'hca62c;

32'h520000: O = 32'hcce66;

32'h540000: O = 32'hcf623;

32'h560000: O = 32'hd1d68;

32'h580000: O = 32'hd4439;

32'h5a0000: O = 32'hd6a99;

32'h5c0000: O = 32'hd908d;

32'h5e0000: O = 32'hdb618;

32'h600000: O = 32'hddb3d;

32'h620000: O = 32'he0000;

32'h640000: O = 32'he2463;

32'h660000: O = 32'he4869;

32'h680000: O = 32'he6c15;

32'h6a0000: O = 32'he8f6a;

32'h6c0000: O = 32'heb26a;

32'h6e0000: O = 32'hed517;

32'h700000: O = 32'hef775;

32'h720000: O = 32'hf1983;

32'h740000: O = 32'hf3b46;

32'h760000: O = 32'hf5cbf;

32'h780000: O = 32'hf7def;

32'h7a0000: O = 32'hf9ed9;

32'h7c0000: O = 32'hfbf7d;

32'h7e0000: O = 32'hfdfdf;

32'h800000: O = 32'h100000;

32'h820000: O = 32'h101fe0;

32'h840000: O = 32'h103f81;

32'h860000: O = 32'h105ee6;

32'h880000: O = 32'h107e0f;

32'h8a0000: O = 32'h109cfd;

32'h8c0000: O = 32'h10bbb3;

32'h8e0000: O = 32'h10da30;

32'h900000: O = 32'h10f876;

32'h920000: O = 32'h111687;

32'h940000: O = 32'h113463;

32'h960000: O = 32'h11520c;

32'h980000: O = 32'h116f83;

32'h9a0000: O = 32'h118cc8;

32'h9c0000: O = 32'h11a9dc;

32'h9e0000: O = 32'h11c6c1;

32'ha00000: O = 32'h11e377;

32'ha20000: O = 32'h120000;

32'ha40000: O = 32'h121c5b;

32'ha60000: O = 32'h12388a;

32'ha80000: O = 32'h12548e;

32'haa0000: O = 32'h127068;

32'hac0000: O = 32'h128c17;

32'hae0000: O = 32'h12a79e;

32'hb00000: O = 32'h12c2fc;

32'hb20000: O = 32'h12de32;

32'hb40000: O = 32'h12f942;

32'hb60000: O = 32'h13142b;

32'hb80000: O = 32'h132eee;

32'hba0000: O = 32'h13498c;

32'hbc0000: O = 32'h136406;

32'hbe0000: O = 32'h137e5b;

32'hc00000: O = 32'h13988e;

32'hc20000: O = 32'h13b29d;

32'hc40000: O = 32'h13cc8a;

32'hc60000: O = 32'h13e655;

32'hc80000: O = 32'h140000;

32'hca0000: O = 32'h141989;

32'hcc0000: O = 32'h1432f2;

32'hce0000: O = 32'h144c3b;

32'hd00000: O = 32'h146565;

32'hd20000: O = 32'h147e70;

32'hd40000: O = 32'h14975c;

32'hd60000: O = 32'h14b02b;

32'hd80000: O = 32'h14c8dc;

32'hda0000: O = 32'h14e16f;

32'hdc0000: O = 32'h14f9e6;

32'hde0000: O = 32'h151241;

32'he00000: O = 32'h152a7f;

32'he20000: O = 32'h1542a2;

32'he40000: O = 32'h155aaa;

32'he60000: O = 32'h157296;

32'he80000: O = 32'h158a68;

32'hea0000: O = 32'h15a220;

32'hec0000: O = 32'h15b9be;

32'hee0000: O = 32'h15d142;

32'hf00000: O = 32'h15e8ad;

32'hf20000: O = 32'h160000;

32'hf40000: O = 32'h161739;

32'hf60000: O = 32'h162e5a;

32'hf80000: O = 32'h164564;

32'hfa0000: O = 32'h165c55;

32'hfc0000: O = 32'h16732f;

32'hfe0000: O = 32'h1689f2; //127 -> 1111111,00000000000000000 

default:

begin

//$display("SQUARE ROOT SAYS: Shit, got %d\n",I << `SCALE);

 O = 32'h00caca;

end

        endcase

end //always    

endmodule

module FixedPointSquareRoot

(

        input wire                                                      Clock,

        input wire                                                      Reset,

        input wire[`LONG_WIDTH-1:0]      Operand,

        input wire                                                      iInputReady,

        output  wire                                            OutputReady,

        output  wire [`WIDTH-1:0]                Result

);

FFD_POSEDGE_SYNCRONOUS_RESET # (1) FFDelay1

(

        .Clock( Clock ),

        .Reset( Reset ),

        .Enable(1'b1 ),

        .D( iInputReady ),

        .Q( OutputReady )

);

//LUT only has values from 0 to 127, lets see if the value is bigger than that

wire wNotInLUT;

assign wNotInLUT = Operand[7+`SCALE];

//If the value is not on the LUT then divide by 64, so SQRT(x) = SQRT(64*x/64)

//=16*SQRT(x/64)

wire[`WIDTH-1:0] wScaledOperand;

assign wScaledOperand = (wNotInLUT == 1'b0 ) ?

   {Operand[`WIDTH-1:`SCALE],{`SCALE{1'b0}}} :     //Aproximate the Square root to an integer value

        {6'b0,Operand[`WIDTH-1:`SCALE+6],{`SCALE{1'b0}}};  //Shift right two bits (divide by 4)

wire [`WIDTH-1:0] wResult,wScaleResult;

SQUAREROOT_LUT SQRT

(

.I(wScaledOperand),

.O(wScaleResult)

);

assign wResult = (wNotInLUT == 1'b0 ) ? wScaleResult : {wScaleResult[`WIDTH-3:0],1'b0};

FFD_POSEDGE_SYNCRONOUS_RESET # (`WIDTH) FFRESULT

(

        .Clock( Clock ),

        .Reset( Reset ),

        .Enable(1'b1 ),

        .D( wResult ),

        .Q( Result )

);

//--------------------------------------------------------------------------------

endmodule